/src/sentencepiece/third_party/libsais/libsais.c

Source
/*--

This file is a part of libsais, a library for linear time suffix array,
longest common prefix array and burrows wheeler transform construction.

   Copyright (c) 2021-2025 Ilya Grebnov <ilya.grebnov@gmail.com>

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.

Please see the file LICENSE for full copyright information.

--*/

#include "libsais.h"

#include <limits.h>
#include <stddef.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#if defined(LIBSAIS_OPENMP)
#include <omp.h>
#else
#define UNUSED(_x) (void)(_x)
#endif

typedef int32_t sa_sint_t;
typedef uint32_t sa_uint_t;
typedef ptrdiff_t fast_sint_t;
typedef size_t fast_uint_t;

#define SAINT_BIT (32)
#define SAINT_MAX INT32_MAX
#define SAINT_MIN INT32_MIN

#define ALPHABET_SIZE (1 << CHAR_BIT)
#define UNBWT_FASTBITS (17)

#define SUFFIX_GROUP_BIT (SAINT_BIT - 1)
#define SUFFIX_GROUP_MARKER (((sa_sint_t)1) << (SUFFIX_GROUP_BIT - 1))

#define BUCKETS_INDEX2(_c, _s) (((_c) << 1) + (_s))
#define BUCKETS_INDEX4(_c, _s) (((_c) << 2) + (_s))

#define LIBSAIS_LOCAL_BUFFER_SIZE (2000)
#define LIBSAIS_PER_THREAD_CACHE_SIZE (24576)

#define LIBSAIS_FLAGS_NONE (0)
#define LIBSAIS_FLAGS_BWT (1)
#define LIBSAIS_FLAGS_GSA (2)

typedef struct LIBSAIS_THREAD_CACHE {
  sa_sint_t symbol;
  sa_sint_t index;
} LIBSAIS_THREAD_CACHE;

typedef union LIBSAIS_THREAD_STATE {
  struct {
    fast_sint_t position;
    fast_sint_t count;

    fast_sint_t m;
    fast_sint_t last_lms_suffix;

    sa_sint_t* buckets;
    LIBSAIS_THREAD_CACHE* cache;
  } state;

  uint8_t padding[64];
} LIBSAIS_THREAD_STATE;

typedef struct LIBSAIS_CONTEXT {
  sa_sint_t* buckets;
  LIBSAIS_THREAD_STATE* thread_state;
  fast_sint_t threads;
} LIBSAIS_CONTEXT;

typedef struct LIBSAIS_UNBWT_CONTEXT {
  sa_uint_t* bucket2;
  uint16_t* fastbits;
  sa_uint_t* buckets;
  fast_sint_t threads;
} LIBSAIS_UNBWT_CONTEXT;

#if defined(__GNUC__) || defined(__clang__)
#define RESTRICT __restrict__
#elif defined(_MSC_VER) || defined(__INTEL_COMPILER)
#define RESTRICT __restrict
#else
#error Your compiler, configuration or platform is not supported.
#endif

#if defined(__has_builtin)
#if __has_builtin(__builtin_prefetch)
#define HAS_BUILTIN_PREFETCH
#endif
#elif defined(__GNUC__) && \
    (((__GNUC__ == 3) && (__GNUC_MINOR__ >= 2)) || (__GNUC__ >= 4))
#define HAS_BUILTIN_PREFETCH
#endif

#if defined(__has_builtin)
#if __has_builtin(__builtin_bswap16)
#define HAS_BUILTIN_BSWAP16
#endif
#elif defined(__GNUC__) && \
    (((__GNUC__ == 4) && (__GNUC_MINOR__ >= 8)) || (__GNUC__ >= 5))
#define HAS_BUILTIN_BSWAP16
#endif

#if defined(HAS_BUILTIN_PREFETCH)
#define libsais_prefetchr(address) \
  __builtin_prefetch((const void*)(address), 0, 3)
#define libsais_prefetchw(address) \
  __builtin_prefetch((const void*)(address), 1, 3)
#elif defined(_M_IX86) || defined(_M_AMD64)
#include <intrin.h>
#define libsais_prefetchr(address) \
  _mm_prefetch((const void*)(address), _MM_HINT_T0)
#define libsais_prefetchw(address) _m_prefetchw((const void*)(address))
#elif defined(_M_ARM)
#include <intrin.h>
#define libsais_prefetchr(address) __prefetch((const void*)(address))
#define libsais_prefetchw(address) __prefetchw((const void*)(address))
#elif defined(_M_ARM64)
#include <intrin.h>
#define libsais_prefetchr(address) __prefetch2((const void*)(address), 0)
#define libsais_prefetchw(address) __prefetch2((const void*)(address), 16)
#else
#error Your compiler, configuration or platform is not supported.
#endif

#if !defined(__LITTLE_ENDIAN__) && !defined(__BIG_ENDIAN__)
#if defined(_LITTLE_ENDIAN) ||                                      \
    (defined(BYTE_ORDER) && defined(LITTLE_ENDIAN) &&               \
     BYTE_ORDER == LITTLE_ENDIAN) ||                                \
    (defined(_BYTE_ORDER) && defined(_LITTLE_ENDIAN) &&             \
     _BYTE_ORDER == _LITTLE_ENDIAN) ||                              \
    (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) &&           \
     __BYTE_ORDER == __LITTLE_ENDIAN) ||                            \
    (defined(__BYTE_ORDER__) && defined(__ORDER_LITTLE_ENDIAN__) && \
     __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__)
#define __LITTLE_ENDIAN__
#elif defined(_BIG_ENDIAN) ||                                    \
    (defined(BYTE_ORDER) && defined(BIG_ENDIAN) &&               \
     BYTE_ORDER == BIG_ENDIAN) ||                                \
    (defined(_BYTE_ORDER) && defined(_BIG_ENDIAN) &&             \
     _BYTE_ORDER == _BIG_ENDIAN) ||                              \
    (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) &&           \
     __BYTE_ORDER == __BIG_ENDIAN) ||                            \
    (defined(__BYTE_ORDER__) && defined(__ORDER_BIG_ENDIAN__) && \
     __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)
#define __BIG_ENDIAN__
#elif defined(_WIN32)
#define __LITTLE_ENDIAN__
#endif
#endif

#if defined(__LITTLE_ENDIAN__) && !defined(__BIG_ENDIAN__)
#if defined(HAS_BUILTIN_BSWAP16)
#define libsais_bswap16(x) (__builtin_bswap16(x))
#elif defined(_MSC_VER) && !defined(__INTEL_COMPILER)
#define libsais_bswap16(x) (_byteswap_ushort(x))
#else
#define libsais_bswap16(x) ((uint16_t)(x >> 8) | (uint16_t)(x << 8))
#endif
#elif !defined(__LITTLE_ENDIAN__) && defined(__BIG_ENDIAN__)
#define libsais_bswap16(x) (x)
#else
#error Your compiler, configuration or platform is not supported.
#endif

static void* libsais_align_up(const void* address, size_t alignment) {
  return (void*)((((ptrdiff_t)address) + ((ptrdiff_t)alignment) - 1) &
                 (-((ptrdiff_t)alignment)));
}

static void* libsais_alloc_aligned(size_t size, size_t alignment) {
  void* address = malloc(size + sizeof(short) + alignment - 1);
  if (address != NULL) {
    void* aligned_address = libsais_align_up(
        (void*)((ptrdiff_t)address + (ptrdiff_t)(sizeof(short))), alignment);
    ((short*)aligned_address)[-1] =
        (short)((ptrdiff_t)aligned_address - (ptrdiff_t)address);

    return aligned_address;
  }

  return NULL;
}

static void libsais_free_aligned(void* aligned_address) {
  if (aligned_address != NULL) {
    free((void*)((ptrdiff_t)aligned_address - ((short*)aligned_address)[-1]));
  }
}

static LIBSAIS_THREAD_STATE* libsais_alloc_thread_state(sa_sint_t threads) {
  LIBSAIS_THREAD_STATE* RESTRICT thread_state =
      (LIBSAIS_THREAD_STATE*)libsais_alloc_aligned(
          (size_t)threads * sizeof(LIBSAIS_THREAD_STATE), 4096);
  sa_sint_t* RESTRICT thread_buckets = (sa_sint_t*)libsais_alloc_aligned(
      (size_t)threads * 4 * ALPHABET_SIZE * sizeof(sa_sint_t), 4096);
  LIBSAIS_THREAD_CACHE* RESTRICT thread_cache =
      (LIBSAIS_THREAD_CACHE*)libsais_alloc_aligned(
          (size_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE *
              sizeof(LIBSAIS_THREAD_CACHE),
          4096);

  if (thread_state != NULL && thread_buckets != NULL && thread_cache != NULL) {
    fast_sint_t t;
    for (t = 0; t < threads; ++t) {
      thread_state[t].state.buckets = thread_buckets;
      thread_buckets += 4 * ALPHABET_SIZE;
      thread_state[t].state.cache = thread_cache;
      thread_cache += LIBSAIS_PER_THREAD_CACHE_SIZE;
    }

    return thread_state;
  }

  libsais_free_aligned(thread_cache);
  libsais_free_aligned(thread_buckets);
  libsais_free_aligned(thread_state);
  return NULL;
}

static void libsais_free_thread_state(LIBSAIS_THREAD_STATE* thread_state) {
  if (thread_state != NULL) {
    libsais_free_aligned(thread_state[0].state.cache);
    libsais_free_aligned(thread_state[0].state.buckets);
    libsais_free_aligned(thread_state);
  }
}

static LIBSAIS_CONTEXT* libsais_create_ctx_main(sa_sint_t threads) {
  LIBSAIS_CONTEXT* RESTRICT ctx =
      (LIBSAIS_CONTEXT*)libsais_alloc_aligned(sizeof(LIBSAIS_CONTEXT), 64);
  sa_sint_t* RESTRICT buckets = (sa_sint_t*)libsais_alloc_aligned(
      (size_t)8 * ALPHABET_SIZE * sizeof(sa_sint_t), 4096);
  LIBSAIS_THREAD_STATE* RESTRICT thread_state =
      threads > 1 ? libsais_alloc_thread_state(threads) : NULL;

  if (ctx != NULL && buckets != NULL &&
      (thread_state != NULL || threads == 1)) {
    ctx->buckets = buckets;
    ctx->threads = threads;
    ctx->thread_state = thread_state;

    return ctx;
  }

  libsais_free_thread_state(thread_state);
  libsais_free_aligned(buckets);
  libsais_free_aligned(ctx);
  return NULL;
}

static void libsais_free_ctx_main(LIBSAIS_CONTEXT* ctx) {
  if (ctx != NULL) {
    libsais_free_thread_state(ctx->thread_state);
    libsais_free_aligned(ctx->buckets);
    libsais_free_aligned(ctx);
  }
}

#if defined(LIBSAIS_OPENMP)

static sa_sint_t libsais_count_negative_marked_suffixes(
    sa_sint_t* RESTRICT SA, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  sa_sint_t count = 0;

  fast_sint_t i;
  for (i = omp_block_start; i < omp_block_start + omp_block_size; ++i) {
    count += (SA[i] < 0);
  }

  return count;
}

static sa_sint_t libsais_count_zero_marked_suffixes(
    sa_sint_t* RESTRICT SA, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  sa_sint_t count = 0;

  fast_sint_t i;
  for (i = omp_block_start; i < omp_block_start + omp_block_size; ++i) {
    count += (SA[i] == 0);
  }

  return count;
}

static void libsais_place_cached_suffixes(sa_sint_t* RESTRICT SA,
                                          LIBSAIS_THREAD_CACHE* RESTRICT cache,
                                          fast_sint_t omp_block_start,
                                          fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&cache[i + 2 * prefetch_distance]);

    libsais_prefetchw(&SA[cache[i + prefetch_distance + 0].symbol]);
    libsais_prefetchw(&SA[cache[i + prefetch_distance + 1].symbol]);
    libsais_prefetchw(&SA[cache[i + prefetch_distance + 2].symbol]);
    libsais_prefetchw(&SA[cache[i + prefetch_distance + 3].symbol]);

    SA[cache[i + 0].symbol] = cache[i + 0].index;
    SA[cache[i + 1].symbol] = cache[i + 1].index;
    SA[cache[i + 2].symbol] = cache[i + 2].index;
    SA[cache[i + 3].symbol] = cache[i + 3].index;
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    SA[cache[i].symbol] = cache[i].index;
  }
}

static void libsais_compact_and_place_cached_suffixes(
    sa_sint_t* RESTRICT SA, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, l;
  for (i = omp_block_start, j = omp_block_start + omp_block_size - 3,
      l = omp_block_start;
       i < j; i += 4) {
    libsais_prefetchw(&cache[i + prefetch_distance]);

    cache[l] = cache[i + 0];
    l += cache[l].symbol >= 0;
    cache[l] = cache[i + 1];
    l += cache[l].symbol >= 0;
    cache[l] = cache[i + 2];
    l += cache[l].symbol >= 0;
    cache[l] = cache[i + 3];
    l += cache[l].symbol >= 0;
  }

  for (j += 3; i < j; i += 1) {
    cache[l] = cache[i];
    l += cache[l].symbol >= 0;
  }

  libsais_place_cached_suffixes(SA, cache, omp_block_start,
                                l - omp_block_start);
}

static void libsais_accumulate_counts_s32_2(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s];
  }
}

static void libsais_accumulate_counts_s32_3(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s] + bucket02[s];
  }
}

static void libsais_accumulate_counts_s32_4(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  sa_sint_t* RESTRICT bucket03 = bucket02 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s] + bucket02[s] + bucket03[s];
  }
}

static void libsais_accumulate_counts_s32_5(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  sa_sint_t* RESTRICT bucket03 = bucket02 - bucket_stride;
  sa_sint_t* RESTRICT bucket04 = bucket03 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] =
        bucket00[s] + bucket01[s] + bucket02[s] + bucket03[s] + bucket04[s];
  }
}

static void libsais_accumulate_counts_s32_6(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  sa_sint_t* RESTRICT bucket03 = bucket02 - bucket_stride;
  sa_sint_t* RESTRICT bucket04 = bucket03 - bucket_stride;
  sa_sint_t* RESTRICT bucket05 = bucket04 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s] + bucket02[s] + bucket03[s] +
                  bucket04[s] + bucket05[s];
  }
}

static void libsais_accumulate_counts_s32_7(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  sa_sint_t* RESTRICT bucket03 = bucket02 - bucket_stride;
  sa_sint_t* RESTRICT bucket04 = bucket03 - bucket_stride;
  sa_sint_t* RESTRICT bucket05 = bucket04 - bucket_stride;
  sa_sint_t* RESTRICT bucket06 = bucket05 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s] + bucket02[s] + bucket03[s] +
                  bucket04[s] + bucket05[s] + bucket06[s];
  }
}

static void libsais_accumulate_counts_s32_8(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  sa_sint_t* RESTRICT bucket03 = bucket02 - bucket_stride;
  sa_sint_t* RESTRICT bucket04 = bucket03 - bucket_stride;
  sa_sint_t* RESTRICT bucket05 = bucket04 - bucket_stride;
  sa_sint_t* RESTRICT bucket06 = bucket05 - bucket_stride;
  sa_sint_t* RESTRICT bucket07 = bucket06 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s] + bucket02[s] + bucket03[s] +
                  bucket04[s] + bucket05[s] + bucket06[s] + bucket07[s];
  }
}

static void libsais_accumulate_counts_s32_9(sa_sint_t* RESTRICT bucket00,
                                            fast_sint_t bucket_size,
                                            fast_sint_t bucket_stride) {
  sa_sint_t* RESTRICT bucket01 = bucket00 - bucket_stride;
  sa_sint_t* RESTRICT bucket02 = bucket01 - bucket_stride;
  sa_sint_t* RESTRICT bucket03 = bucket02 - bucket_stride;
  sa_sint_t* RESTRICT bucket04 = bucket03 - bucket_stride;
  sa_sint_t* RESTRICT bucket05 = bucket04 - bucket_stride;
  sa_sint_t* RESTRICT bucket06 = bucket05 - bucket_stride;
  sa_sint_t* RESTRICT bucket07 = bucket06 - bucket_stride;
  sa_sint_t* RESTRICT bucket08 = bucket07 - bucket_stride;
  fast_sint_t s;
  for (s = 0; s < bucket_size; s += 1) {
    bucket00[s] = bucket00[s] + bucket01[s] + bucket02[s] + bucket03[s] +
                  bucket04[s] + bucket05[s] + bucket06[s] + bucket07[s] +
                  bucket08[s];
  }
}

static void libsais_accumulate_counts_s32(sa_sint_t* RESTRICT buckets,
                                          fast_sint_t bucket_size,
                                          fast_sint_t bucket_stride,
                                          fast_sint_t num_buckets) {
  while (num_buckets >= 9) {
    libsais_accumulate_counts_s32_9(buckets - (num_buckets - 9) * bucket_stride,
                                    bucket_size, bucket_stride);
    num_buckets -= 8;
  }

  switch (num_buckets) {
    case 1:
      break;
    case 2:
      libsais_accumulate_counts_s32_2(buckets, bucket_size, bucket_stride);
      break;
    case 3:
      libsais_accumulate_counts_s32_3(buckets, bucket_size, bucket_stride);
      break;
    case 4:
      libsais_accumulate_counts_s32_4(buckets, bucket_size, bucket_stride);
      break;
    case 5:
      libsais_accumulate_counts_s32_5(buckets, bucket_size, bucket_stride);
      break;
    case 6:
      libsais_accumulate_counts_s32_6(buckets, bucket_size, bucket_stride);
      break;
    case 7:
      libsais_accumulate_counts_s32_7(buckets, bucket_size, bucket_stride);
      break;
    case 8:
      libsais_accumulate_counts_s32_8(buckets, bucket_size, bucket_stride);
      break;
    default:
      break;
  }
}

#endif

static void libsais_flip_suffix_markers_omp(sa_sint_t* RESTRICT SA, sa_sint_t l,
                                            sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && l >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (l / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : l - omp_block_start;

    fast_sint_t i;
    for (i = omp_block_start; i < omp_block_start + omp_block_size; ++i) {
      SA[i] ^= SAINT_MIN;
    }
  }
}

static void libsais_gather_lms_suffixes_8u(const uint8_t* RESTRICT T,
                                           sa_sint_t* RESTRICT SA, sa_sint_t n,
                                           fast_sint_t m,
                                           fast_sint_t omp_block_start,
                                           fast_sint_t omp_block_size) {
  if (omp_block_size > 0) {
    const fast_sint_t prefetch_distance = 256;

    fast_sint_t i, j = omp_block_start + omp_block_size,
                   c0 = T[omp_block_start + omp_block_size - 1], c1 = -1;

    while (j < n && (c1 = T[j]) == c0) {
      ++j;
    }

    fast_uint_t f0 = c0 >= c1, f1 = 0;

    for (i = omp_block_start + omp_block_size - 2, j = omp_block_start + 3;
         i >= j; i -= 4) {
      libsais_prefetchr(&T[i - prefetch_distance]);

      c1 = T[i - 0];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f1 & ~f0);
      c0 = T[i - 1];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 0);
      m -= (f0 & ~f1);
      c1 = T[i - 2];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i - 1);
      m -= (f1 & ~f0);
      c0 = T[i - 3];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 2);
      m -= (f0 & ~f1);
    }

    for (j -= 3; i >= j; i -= 1) {
      c1 = c0;
      c0 = T[i];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f0 & ~f1);
    }

    SA[m] = (sa_sint_t)(i + 1);
  }
}

static void libsais_gather_lms_suffixes_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536 && \
                                                  omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_gather_lms_suffixes_8u(T, SA, n, (fast_sint_t)n - 1,
                                     omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      fast_sint_t t, m = 0;
      for (t = omp_num_threads - 1; t > omp_thread_num; --t) {
        m += thread_state[t].state.m;
      }

      libsais_gather_lms_suffixes_8u(T, SA, n, (fast_sint_t)n - 1 - m,
                                     omp_block_start, omp_block_size);

#pragma omp barrier

      if (thread_state[omp_thread_num].state.m > 0) {
        SA[(fast_sint_t)n - 1 - m] =
            (sa_sint_t)thread_state[omp_thread_num].state.last_lms_suffix;
      }
    }
#endif
  }
}

static sa_sint_t libsais_gather_lms_suffixes_32s(const sa_sint_t* RESTRICT T,
                                                 sa_sint_t* RESTRICT SA,
                                                 sa_sint_t n) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t i = n - 2;
  sa_sint_t m = n - 1;
  fast_uint_t f0 = 1;
  fast_uint_t f1 = 0;
  fast_sint_t c0 = T[n - 1];
  fast_sint_t c1 = 0;

  for (; i >= 3; i -= 4) {
    libsais_prefetchr(&T[i - prefetch_distance]);

    c1 = T[i - 0];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = i + 1;
    m -= (sa_sint_t)(f1 & ~f0);
    c0 = T[i - 1];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    SA[m] = i - 0;
    m -= (sa_sint_t)(f0 & ~f1);
    c1 = T[i - 2];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = i - 1;
    m -= (sa_sint_t)(f1 & ~f0);
    c0 = T[i - 3];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    SA[m] = i - 2;
    m -= (sa_sint_t)(f0 & ~f1);
  }

  for (; i >= 0; i -= 1) {
    c1 = c0;
    c0 = T[i];
    f1 = f0;
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    SA[m] = i + 1;
    m -= (sa_sint_t)(f0 & ~f1);
  }

  return n - 1 - m;
}

static sa_sint_t libsais_gather_compacted_lms_suffixes_32s(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t i = n - 2;
  sa_sint_t m = n - 1;
  fast_uint_t f0 = 1;
  fast_uint_t f1 = 0;
  fast_sint_t c0 = T[n - 1];
  fast_sint_t c1 = 0;

  for (; i >= 3; i -= 4) {
    libsais_prefetchr(&T[i - prefetch_distance]);

    c1 = T[i - 0];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = i + 1;
    m -= (sa_sint_t)(f1 & ~f0 & (c0 >= 0));
    c0 = T[i - 1];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    SA[m] = i - 0;
    m -= (sa_sint_t)(f0 & ~f1 & (c1 >= 0));
    c1 = T[i - 2];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = i - 1;
    m -= (sa_sint_t)(f1 & ~f0 & (c0 >= 0));
    c0 = T[i - 3];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    SA[m] = i - 2;
    m -= (sa_sint_t)(f0 & ~f1 & (c1 >= 0));
  }

  for (; i >= 0; i -= 1) {
    c1 = c0;
    c0 = T[i];
    f1 = f0;
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    SA[m] = i + 1;
    m -= (sa_sint_t)(f0 & ~f1 & (c1 >= 0));
  }

  return n - 1 - m;
}

#if defined(LIBSAIS_OPENMP)

static void libsais_count_lms_suffixes_32s_4k(const sa_sint_t* RESTRICT T,
                                              sa_sint_t n, sa_sint_t k,
                                              sa_sint_t* RESTRICT buckets) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, 4 * (size_t)k * sizeof(sa_sint_t));

  sa_sint_t i = n - 2;
  fast_uint_t f0 = 1;
  fast_uint_t f1 = 0;
  fast_sint_t c0 = T[n - 1];
  fast_sint_t c1 = 0;

  for (; i >= prefetch_distance + 3; i -= 4) {
    libsais_prefetchr(&T[i - 2 * prefetch_distance]);

    libsais_prefetchw(
        &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 0], 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 1], 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 2], 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 3], 0)]);

    c1 = T[i - 0];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;

    c0 = T[i - 1];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;

    c1 = T[i - 2];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;

    c0 = T[i - 3];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;
  }

  for (; i >= 0; i -= 1) {
    c1 = c0;
    c0 = T[i];
    f1 = f0;
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;
  }

  buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0)]++;
}

#endif

static void libsais_count_lms_suffixes_32s_2k(const sa_sint_t* RESTRICT T,
                                              sa_sint_t n, sa_sint_t k,
                                              sa_sint_t* RESTRICT buckets) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, 2 * (size_t)k * sizeof(sa_sint_t));

  sa_sint_t i = n - 2;
  fast_uint_t f0 = 1;
  fast_uint_t f1 = 0;
  fast_sint_t c0 = T[n - 1];
  fast_sint_t c1 = 0;

  for (; i >= prefetch_distance + 3; i -= 4) {
    libsais_prefetchr(&T[i - 2 * prefetch_distance]);

    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 0], 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 1], 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 2], 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 3], 0)]);

    c1 = T[i - 0];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

    c0 = T[i - 1];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;

    c1 = T[i - 2];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

    c0 = T[i - 3];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
  }

  for (; i >= 0; i -= 1) {
    c1 = c0;
    c0 = T[i];
    f1 = f0;
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
  }

  buckets[BUCKETS_INDEX2((fast_uint_t)c0, 0)]++;
}

#if defined(LIBSAIS_OPENMP)

static void libsais_count_compacted_lms_suffixes_32s_2k(
    const sa_sint_t* RESTRICT T, sa_sint_t n, sa_sint_t k,
    sa_sint_t* RESTRICT buckets) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, 2 * (size_t)k * sizeof(sa_sint_t));

  sa_sint_t i = n - 2;
  fast_uint_t f0 = 1;
  fast_uint_t f1 = 0;
  fast_sint_t c0 = T[n - 1];
  fast_sint_t c1 = 0;

  for (; i >= prefetch_distance + 3; i -= 4) {
    libsais_prefetchr(&T[i - 2 * prefetch_distance]);

    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 0] & SAINT_MAX, 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 1] & SAINT_MAX, 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 2] & SAINT_MAX, 0)]);
    libsais_prefetchw(
        &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 3] & SAINT_MAX, 0)]);

    c1 = T[i - 0];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    c0 &= SAINT_MAX;
    buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

    c0 = T[i - 1];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    c1 &= SAINT_MAX;
    buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;

    c1 = T[i - 2];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    c0 &= SAINT_MAX;
    buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

    c0 = T[i - 3];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    c1 &= SAINT_MAX;
    buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
  }

  for (; i >= 0; i -= 1) {
    c1 = c0;
    c0 = T[i];
    f1 = f0;
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    c1 &= SAINT_MAX;
    buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
  }

  c0 &= SAINT_MAX;
  buckets[BUCKETS_INDEX2((fast_uint_t)c0, 0)]++;
}

#endif

static sa_sint_t libsais_count_and_gather_lms_suffixes_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  memset(buckets, 0, (size_t)4 * ALPHABET_SIZE * sizeof(sa_sint_t));

  fast_sint_t m = omp_block_start + omp_block_size - 1;

  if (omp_block_size > 0) {
    const fast_sint_t prefetch_distance = 256;

    fast_sint_t i, j = m + 1, c0 = T[m], c1 = -1;

    while (j < n && (c1 = T[j]) == c0) {
      ++j;
    }

    fast_uint_t f0 = c0 >= c1, f1 = 0;

    for (i = m - 1, j = omp_block_start + 3; i >= j; i -= 4) {
      libsais_prefetchr(&T[i - prefetch_distance]);

      c1 = T[i - 0];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f1 & ~f0);
      buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;

      c0 = T[i - 1];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 0);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;

      c1 = T[i - 2];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i - 1);
      m -= (f1 & ~f0);
      buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;

      c0 = T[i - 3];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 2);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;
    }

    for (j -= 3; i >= j; i -= 1) {
      c1 = c0;
      c0 = T[i];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;
    }

    c1 = (i >= 0) ? T[i] : -1;
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = (sa_sint_t)(i + 1);
    m -= (f1 & ~f0);
    buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;
  }

  return (sa_sint_t)(omp_block_start + omp_block_size - 1 - m);
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t m = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536 && \
                                                  omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      m = libsais_count_and_gather_lms_suffixes_8u(
          T, SA, n, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.position =
            omp_block_start + omp_block_size;
        thread_state[omp_thread_num].state.m =
            libsais_count_and_gather_lms_suffixes_8u(
                T, SA, n, thread_state[omp_thread_num].state.buckets,
                omp_block_start, omp_block_size);

        if (thread_state[omp_thread_num].state.m > 0) {
          thread_state[omp_thread_num].state.last_lms_suffix =
              SA[thread_state[omp_thread_num].state.position - 1];
        }
      }

#pragma omp barrier

#pragma omp master
      {
        memset(buckets, 0, (size_t)4 * ALPHABET_SIZE * sizeof(sa_sint_t));

        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          m += (sa_sint_t)thread_state[t].state.m;

          if (t != omp_num_threads - 1 && thread_state[t].state.m > 0) {
            memcpy(
                &SA[n - m],
                &SA[thread_state[t].state.position - thread_state[t].state.m],
                (size_t)thread_state[t].state.m * sizeof(sa_sint_t));
          }

          {
            sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
            fast_sint_t s;
            for (s = 0; s < 4 * ALPHABET_SIZE; s += 1) {
              sa_sint_t A = buckets[s], B = temp_bucket[s];
              buckets[s] = A + B;
              temp_bucket[s] = A;
            }
          }
        }
      }
    }
#endif
  }

  return m;
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_4k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  memset(buckets, 0, 4 * (size_t)k * sizeof(sa_sint_t));

  fast_sint_t m = omp_block_start + omp_block_size - 1;

  if (omp_block_size > 0) {
    const fast_sint_t prefetch_distance = 64;

    fast_sint_t i, j = m + 1, c0 = T[m], c1 = -1;

    while (j < n && (c1 = T[j]) == c0) {
      ++j;
    }

    fast_uint_t f0 = c0 >= c1, f1 = 0;

    for (i = m - 1, j = omp_block_start + prefetch_distance + 3; i >= j;
         i -= 4) {
      libsais_prefetchr(&T[i - 2 * prefetch_distance]);

      libsais_prefetchw(
          &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 0], 0)]);
      libsais_prefetchw(
          &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 1], 0)]);
      libsais_prefetchw(
          &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 2], 0)]);
      libsais_prefetchw(
          &buckets[BUCKETS_INDEX4(T[i - prefetch_distance - 3], 0)]);

      c1 = T[i - 0];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f1 & ~f0);
      buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;

      c0 = T[i - 1];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 0);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;

      c1 = T[i - 2];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i - 1);
      m -= (f1 & ~f0);
      buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;

      c0 = T[i - 3];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 2);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;
    }

    for (j -= prefetch_distance + 3; i >= j; i -= 1) {
      c1 = c0;
      c0 = T[i];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]++;
    }

    c1 = (i >= 0) ? T[i] : -1;
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = (sa_sint_t)(i + 1);
    m -= (f1 & ~f0);
    buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0 + f1)]++;
  }

  return (sa_sint_t)(omp_block_start + omp_block_size - 1 - m);
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_2k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  memset(buckets, 0, 2 * (size_t)k * sizeof(sa_sint_t));

  fast_sint_t m = omp_block_start + omp_block_size - 1;

  if (omp_block_size > 0) {
    const fast_sint_t prefetch_distance = 64;

    fast_sint_t i, j = m + 1, c0 = T[m], c1 = -1;

    while (j < n && (c1 = T[j]) == c0) {
      ++j;
    }

    fast_uint_t f0 = c0 >= c1, f1 = 0;

    for (i = m - 1, j = omp_block_start + prefetch_distance + 3; i >= j;
         i -= 4) {
      libsais_prefetchr(&T[i - 2 * prefetch_distance]);

      libsais_prefetchw(
          &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 0], 0)]);
      libsais_prefetchw(
          &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 1], 0)]);
      libsais_prefetchw(
          &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 2], 0)]);
      libsais_prefetchw(
          &buckets[BUCKETS_INDEX2(T[i - prefetch_distance - 3], 0)]);

      c1 = T[i - 0];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f1 & ~f0);
      buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

      c0 = T[i - 1];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 0);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;

      c1 = T[i - 2];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i - 1);
      m -= (f1 & ~f0);
      buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

      c0 = T[i - 3];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 2);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
    }

    for (j -= prefetch_distance + 3; i >= j; i -= 1) {
      c1 = c0;
      c0 = T[i];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f0 & ~f1);
      buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
    }

    c1 = (i >= 0) ? T[i] : -1;
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = (sa_sint_t)(i + 1);
    m -= (f1 & ~f0);
    buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;
  }

  return (sa_sint_t)(omp_block_start + omp_block_size - 1 - m);
}

static sa_sint_t libsais_count_and_gather_compacted_lms_suffixes_32s_2k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  memset(buckets, 0, 2 * (size_t)k * sizeof(sa_sint_t));

  fast_sint_t m = omp_block_start + omp_block_size - 1;

  if (omp_block_size > 0) {
    const fast_sint_t prefetch_distance = 64;

    fast_sint_t i, j = m + 1, c0 = T[m], c1 = -1;

    while (j < n && (c1 = T[j]) == c0) {
      ++j;
    }

    fast_uint_t f0 = c0 >= c1, f1 = 0;

    for (i = m - 1, j = omp_block_start + prefetch_distance + 3; i >= j;
         i -= 4) {
      libsais_prefetchr(&T[i - 2 * prefetch_distance]);

      libsais_prefetchw(&buckets[BUCKETS_INDEX2(
          T[i - prefetch_distance - 0] & SAINT_MAX, 0)]);
      libsais_prefetchw(&buckets[BUCKETS_INDEX2(
          T[i - prefetch_distance - 1] & SAINT_MAX, 0)]);
      libsais_prefetchw(&buckets[BUCKETS_INDEX2(
          T[i - prefetch_distance - 2] & SAINT_MAX, 0)]);
      libsais_prefetchw(&buckets[BUCKETS_INDEX2(
          T[i - prefetch_distance - 3] & SAINT_MAX, 0)]);

      c1 = T[i - 0];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f1 & ~f0 & (c0 >= 0));
      c0 &= SAINT_MAX;
      buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

      c0 = T[i - 1];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 0);
      m -= (f0 & ~f1 & (c1 >= 0));
      c1 &= SAINT_MAX;
      buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;

      c1 = T[i - 2];
      f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
      SA[m] = (sa_sint_t)(i - 1);
      m -= (f1 & ~f0 & (c0 >= 0));
      c0 &= SAINT_MAX;
      buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;

      c0 = T[i - 3];
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i - 2);
      m -= (f0 & ~f1 & (c1 >= 0));
      c1 &= SAINT_MAX;
      buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
    }

    for (j -= prefetch_distance + 3; i >= j; i -= 1) {
      c1 = c0;
      c0 = T[i];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      SA[m] = (sa_sint_t)(i + 1);
      m -= (f0 & ~f1 & (c1 >= 0));
      c1 &= SAINT_MAX;
      buckets[BUCKETS_INDEX2((fast_uint_t)c1, (f0 & ~f1))]++;
    }

    c1 = (i >= 0) ? T[i] : -1;
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    SA[m] = (sa_sint_t)(i + 1);
    m -= (f1 & ~f0 & (c0 >= 0));
    c0 &= SAINT_MAX;
    buckets[BUCKETS_INDEX2((fast_uint_t)c0, (f1 & ~f0))]++;
  }

  return (sa_sint_t)(omp_block_start + omp_block_size - 1 - m);
}

#if defined(LIBSAIS_OPENMP)

static fast_sint_t libsais_get_bucket_stride(fast_sint_t free_space,
                                             fast_sint_t bucket_size,
                                             fast_sint_t num_buckets) {
  fast_sint_t bucket_size_1024 = (bucket_size + 1023) & (-1024);
  if (free_space / (num_buckets - 1) >= bucket_size_1024) {
    return bucket_size_1024;
  }
  fast_sint_t bucket_size_16 = (bucket_size + 15) & (-16);
  if (free_space / (num_buckets - 1) >= bucket_size_16) {
    return bucket_size_16;
  }

  return bucket_size;
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_4k_fs_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t local_buckets,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t m = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(local_buckets);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      m = libsais_count_and_gather_lms_suffixes_32s_4k(
          T, SA, n, k, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      fast_sint_t bucket_size = 4 * (fast_sint_t)k;
      fast_sint_t free_space =
          local_buckets ? LIBSAIS_LOCAL_BUFFER_SIZE : (buckets - &SA[n]);
      fast_sint_t bucket_stride =
          libsais_get_bucket_stride(free_space, bucket_size, omp_num_threads);

      {
        thread_state[omp_thread_num].state.position =
            omp_block_start + omp_block_size;
        thread_state[omp_thread_num].state.count =
            libsais_count_and_gather_lms_suffixes_32s_4k(
                T, SA, n, k, buckets - (omp_thread_num * bucket_stride),
                omp_block_start, omp_block_size);
      }

#pragma omp barrier

      if (omp_thread_num == omp_num_threads - 1) {
        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          m += (sa_sint_t)thread_state[t].state.count;

          if (t != omp_num_threads - 1 && thread_state[t].state.count > 0) {
            memcpy(&SA[n - m],
                   &SA[thread_state[t].state.position -
                       thread_state[t].state.count],
                   (size_t)thread_state[t].state.count * sizeof(sa_sint_t));
          }
        }
      } else {
        omp_num_threads = omp_num_threads - 1;
        omp_block_stride = (bucket_size / omp_num_threads) & (-16);
        omp_block_start = omp_thread_num * omp_block_stride;
        omp_block_size = omp_thread_num < omp_num_threads - 1
                             ? omp_block_stride
                             : bucket_size - omp_block_start;

        libsais_accumulate_counts_s32(buckets + omp_block_start, omp_block_size,
                                      bucket_stride, omp_num_threads + 1);
      }
    }
#endif
  }

  return m;
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_2k_fs_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t local_buckets,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t m = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(local_buckets);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      m = libsais_count_and_gather_lms_suffixes_32s_2k(
          T, SA, n, k, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      fast_sint_t bucket_size = 2 * (fast_sint_t)k;
      fast_sint_t free_space =
          local_buckets ? LIBSAIS_LOCAL_BUFFER_SIZE : (buckets - &SA[n]);
      fast_sint_t bucket_stride =
          libsais_get_bucket_stride(free_space, bucket_size, omp_num_threads);

      {
        thread_state[omp_thread_num].state.position =
            omp_block_start + omp_block_size;
        thread_state[omp_thread_num].state.count =
            libsais_count_and_gather_lms_suffixes_32s_2k(
                T, SA, n, k, buckets - (omp_thread_num * bucket_stride),
                omp_block_start, omp_block_size);
      }

#pragma omp barrier

      if (omp_thread_num == omp_num_threads - 1) {
        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          m += (sa_sint_t)thread_state[t].state.count;

          if (t != omp_num_threads - 1 && thread_state[t].state.count > 0) {
            memcpy(&SA[n - m],
                   &SA[thread_state[t].state.position -
                       thread_state[t].state.count],
                   (size_t)thread_state[t].state.count * sizeof(sa_sint_t));
          }
        }
      } else {
        omp_num_threads = omp_num_threads - 1;
        omp_block_stride = (bucket_size / omp_num_threads) & (-16);
        omp_block_start = omp_thread_num * omp_block_stride;
        omp_block_size = omp_thread_num < omp_num_threads - 1
                             ? omp_block_stride
                             : bucket_size - omp_block_start;

        libsais_accumulate_counts_s32(buckets + omp_block_start, omp_block_size,
                                      bucket_stride, omp_num_threads + 1);
      }
    }
#endif
  }

  return m;
}

static void libsais_count_and_gather_compacted_lms_suffixes_32s_2k_fs_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t local_buckets,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(local_buckets);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_count_and_gather_compacted_lms_suffixes_32s_2k(
          T, SA, n, k, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      fast_sint_t bucket_size = 2 * (fast_sint_t)k;
      fast_sint_t free_space =
          local_buckets ? LIBSAIS_LOCAL_BUFFER_SIZE
                        : (buckets - &SA[(fast_sint_t)n + (fast_sint_t)n]);
      fast_sint_t bucket_stride =
          libsais_get_bucket_stride(free_space, bucket_size, omp_num_threads);

      {
        thread_state[omp_thread_num].state.position =
            omp_block_start + omp_block_size;
        thread_state[omp_thread_num].state.count =
            libsais_count_and_gather_compacted_lms_suffixes_32s_2k(
                T, SA + n, n, k, buckets - (omp_thread_num * bucket_stride),
                omp_block_start, omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t t, m = 0;
        for (t = omp_num_threads - 1; t >= omp_thread_num; --t) {
          m += (sa_sint_t)thread_state[t].state.count;
        }

        if (thread_state[omp_thread_num].state.count > 0) {
          memcpy(&SA[n - m],
                 &SA[n + thread_state[omp_thread_num].state.position -
                     thread_state[omp_thread_num].state.count],
                 (size_t)thread_state[omp_thread_num].state.count *
                     sizeof(sa_sint_t));
        }
      }

      {
        omp_block_stride = (bucket_size / omp_num_threads) & (-16);
        omp_block_start = omp_thread_num * omp_block_stride;
        omp_block_size = omp_thread_num < omp_num_threads - 1
                             ? omp_block_stride
                             : bucket_size - omp_block_start;

        libsais_accumulate_counts_s32(buckets + omp_block_start, omp_block_size,
                                      bucket_stride, omp_num_threads);
      }
    }
#endif
  }
}

#endif

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_4k_nofs_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads) {
  sa_sint_t m = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(2) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_num_threads = 1;
#endif
    if (omp_num_threads == 1) {
      m = libsais_count_and_gather_lms_suffixes_32s_4k(T, SA, n, k, buckets, 0,
                                                       n);
    }
#if defined(LIBSAIS_OPENMP)
    else if (omp_thread_num == 0) {
      libsais_count_lms_suffixes_32s_4k(T, n, k, buckets);
    } else {
      m = libsais_gather_lms_suffixes_32s(T, SA, n);
    }
#endif
  }

  return m;
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_2k_nofs_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads) {
  sa_sint_t m = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(2) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_num_threads = 1;
#endif
    if (omp_num_threads == 1) {
      m = libsais_count_and_gather_lms_suffixes_32s_2k(T, SA, n, k, buckets, 0,
                                                       n);
    }
#if defined(LIBSAIS_OPENMP)
    else if (omp_thread_num == 0) {
      libsais_count_lms_suffixes_32s_2k(T, n, k, buckets);
    } else {
      m = libsais_gather_lms_suffixes_32s(T, SA, n);
    }
#endif
  }

  return m;
}

static sa_sint_t
libsais_count_and_gather_compacted_lms_suffixes_32s_2k_nofs_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads) {
  sa_sint_t m = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(2) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_num_threads = 1;
#endif
    if (omp_num_threads == 1) {
      m = libsais_count_and_gather_compacted_lms_suffixes_32s_2k(T, SA, n, k,
                                                                 buckets, 0, n);
    }
#if defined(LIBSAIS_OPENMP)
    else if (omp_thread_num == 0) {
      libsais_count_compacted_lms_suffixes_32s_2k(T, n, k, buckets);
    } else {
      m = libsais_gather_compacted_lms_suffixes_32s(T, SA, n);
    }
#endif
  }

  return m;
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_4k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t local_buckets,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t m;

#if defined(LIBSAIS_OPENMP)
  fast_sint_t free_space =
      local_buckets ? LIBSAIS_LOCAL_BUFFER_SIZE : (buckets - &SA[n]);
  sa_sint_t max_threads =
      (sa_sint_t)(free_space / ((4 * (fast_sint_t)k + 15) & (-16)));
  if (max_threads > threads) {
    max_threads = threads;
  }

  if (max_threads > 1 && n >= 65536 && n / k >= 2) {
    if (max_threads > n / 16 / k) {
      max_threads = n / 16 / k;
    }
    m = libsais_count_and_gather_lms_suffixes_32s_4k_fs_omp(
        T, SA, n, k, buckets, local_buckets, max_threads > 2 ? max_threads : 2,
        thread_state);
  } else
#else
  UNUSED(local_buckets);
  UNUSED(thread_state);
#endif
  {
    m = libsais_count_and_gather_lms_suffixes_32s_4k_nofs_omp(T, SA, n, k,
                                                              buckets, threads);
  }

  return m;
}

static sa_sint_t libsais_count_and_gather_lms_suffixes_32s_2k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t local_buckets,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t m;

#if defined(LIBSAIS_OPENMP)
  fast_sint_t free_space =
      local_buckets ? LIBSAIS_LOCAL_BUFFER_SIZE : (buckets - &SA[n]);
  sa_sint_t max_threads =
      (sa_sint_t)(free_space / ((2 * (fast_sint_t)k + 15) & (-16)));
  if (max_threads > threads) {
    max_threads = threads;
  }

  if (max_threads > 1 && n >= 65536 && n / k >= 2) {
    if (max_threads > n / 8 / k) {
      max_threads = n / 8 / k;
    }
    m = libsais_count_and_gather_lms_suffixes_32s_2k_fs_omp(
        T, SA, n, k, buckets, local_buckets, max_threads > 2 ? max_threads : 2,
        thread_state);
  } else
#else
  UNUSED(local_buckets);
  UNUSED(thread_state);
#endif
  {
    m = libsais_count_and_gather_lms_suffixes_32s_2k_nofs_omp(T, SA, n, k,
                                                              buckets, threads);
  }

  return m;
}

static void libsais_count_and_gather_compacted_lms_suffixes_32s_2k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t local_buckets,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
  fast_sint_t free_space =
      local_buckets ? LIBSAIS_LOCAL_BUFFER_SIZE
                    : (buckets - &SA[(fast_sint_t)n + (fast_sint_t)n]);
  sa_sint_t max_threads =
      (sa_sint_t)(free_space / ((2 * (fast_sint_t)k + 15) & (-16)));
  if (max_threads > threads) {
    max_threads = threads;
  }

  if (!local_buckets && max_threads > 1 && n >= 65536 && n / k >= 2) {
    if (max_threads > n / 8 / k) {
      max_threads = n / 8 / k;
    }
    libsais_count_and_gather_compacted_lms_suffixes_32s_2k_fs_omp(
        T, SA, n, k, buckets, local_buckets, max_threads > 2 ? max_threads : 2,
        thread_state);
  } else
#else
  UNUSED(local_buckets);
  UNUSED(thread_state);
#endif
  {
    libsais_count_and_gather_compacted_lms_suffixes_32s_2k_nofs_omp(
        T, SA, n, k, buckets, threads);
  }
}

static void libsais_count_suffixes_32s(const sa_sint_t* RESTRICT T, sa_sint_t n,
                                       sa_sint_t k,
                                       sa_sint_t* RESTRICT buckets) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j;
  for (i = 0, j = (fast_sint_t)n - 7; i < j; i += 8) {
    libsais_prefetchr(&T[i + prefetch_distance]);

    buckets[T[i + 0]]++;
    buckets[T[i + 1]]++;
    buckets[T[i + 2]]++;
    buckets[T[i + 3]]++;
    buckets[T[i + 4]]++;
    buckets[T[i + 5]]++;
    buckets[T[i + 6]]++;
    buckets[T[i + 7]]++;
  }

  for (j += 7; i < j; i += 1) {
    buckets[T[i]]++;
  }
}

static sa_sint_t libsais_initialize_buckets_start_and_end_8u(
    sa_sint_t* RESTRICT buckets, sa_sint_t* RESTRICT freq) {
  sa_sint_t* RESTRICT bucket_start = &buckets[6 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT bucket_end = &buckets[7 * ALPHABET_SIZE];

  fast_sint_t k = -1;

  if (freq != NULL) {
    fast_sint_t i, j;
    sa_sint_t sum = 0;
    for (i = BUCKETS_INDEX4(0, 0), j = 0;
         i <= BUCKETS_INDEX4(ALPHABET_SIZE - 1, 0);
         i += BUCKETS_INDEX4(1, 0), j += 1) {
      sa_sint_t total = buckets[i + BUCKETS_INDEX4(0, 0)] +
                        buckets[i + BUCKETS_INDEX4(0, 1)] +
                        buckets[i + BUCKETS_INDEX4(0, 2)] +
                        buckets[i + BUCKETS_INDEX4(0, 3)];

      bucket_start[j] = sum;
      sum += total;
      bucket_end[j] = sum;
      k = total > 0 ? j : k;
      freq[j] = total;
    }
  } else {
    fast_sint_t i, j;
    sa_sint_t sum = 0;
    for (i = BUCKETS_INDEX4(0, 0), j = 0;
         i <= BUCKETS_INDEX4(ALPHABET_SIZE - 1, 0);
         i += BUCKETS_INDEX4(1, 0), j += 1) {
      sa_sint_t total = buckets[i + BUCKETS_INDEX4(0, 0)] +
                        buckets[i + BUCKETS_INDEX4(0, 1)] +
                        buckets[i + BUCKETS_INDEX4(0, 2)] +
                        buckets[i + BUCKETS_INDEX4(0, 3)];

      bucket_start[j] = sum;
      sum += total;
      bucket_end[j] = sum;
      k = total > 0 ? j : k;
    }
  }

  return (sa_sint_t)(k + 1);
}

static void libsais_initialize_buckets_start_and_end_32s_6k(
    sa_sint_t k, sa_sint_t* RESTRICT buckets) {
  sa_sint_t* RESTRICT bucket_start = &buckets[4 * (fast_sint_t)k];
  sa_sint_t* RESTRICT bucket_end = &buckets[5 * (fast_sint_t)k];

  fast_sint_t i, j;
  sa_sint_t sum = 0;
  for (i = BUCKETS_INDEX4(0, 0), j = 0;
       i <= BUCKETS_INDEX4((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX4(1, 0), j += 1) {
    bucket_start[j] = sum;
    sum +=
        buckets[i + BUCKETS_INDEX4(0, 0)] + buckets[i + BUCKETS_INDEX4(0, 1)] +
        buckets[i + BUCKETS_INDEX4(0, 2)] + buckets[i + BUCKETS_INDEX4(0, 3)];
    bucket_end[j] = sum;
  }
}

static void libsais_initialize_buckets_start_and_end_32s_4k(
    sa_sint_t k, sa_sint_t* RESTRICT buckets) {
  sa_sint_t* RESTRICT bucket_start = &buckets[2 * (fast_sint_t)k];
  sa_sint_t* RESTRICT bucket_end = &buckets[3 * (fast_sint_t)k];

  fast_sint_t i, j;
  sa_sint_t sum = 0;
  for (i = BUCKETS_INDEX2(0, 0), j = 0;
       i <= BUCKETS_INDEX2((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX2(1, 0), j += 1) {
    bucket_start[j] = sum;
    sum +=
        buckets[i + BUCKETS_INDEX2(0, 0)] + buckets[i + BUCKETS_INDEX2(0, 1)];
    bucket_end[j] = sum;
  }
}

static void libsais_initialize_buckets_end_32s_2k(sa_sint_t k,
                                                  sa_sint_t* RESTRICT buckets) {
  fast_sint_t i;
  sa_sint_t sum0 = 0;
  for (i = BUCKETS_INDEX2(0, 0); i <= BUCKETS_INDEX2((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX2(1, 0)) {
    sum0 +=
        buckets[i + BUCKETS_INDEX2(0, 0)] + buckets[i + BUCKETS_INDEX2(0, 1)];
    buckets[i + BUCKETS_INDEX2(0, 0)] = sum0;
  }
}

static void libsais_initialize_buckets_start_and_end_32s_2k(
    sa_sint_t k, sa_sint_t* RESTRICT buckets) {
  fast_sint_t i, j;
  for (i = BUCKETS_INDEX2(0, 0), j = 0;
       i <= BUCKETS_INDEX2((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX2(1, 0), j += 1) {
    buckets[j] = buckets[i];
  }

  buckets[k] = 0;
  memcpy(&buckets[k + 1], buckets, ((size_t)k - 1) * sizeof(sa_sint_t));
}

static void libsais_initialize_buckets_start_32s_1k(
    sa_sint_t k, sa_sint_t* RESTRICT buckets) {
  fast_sint_t i;
  sa_sint_t sum = 0;
  for (i = 0; i <= (fast_sint_t)k - 1; i += 1) {
    sa_sint_t tmp = buckets[i];
    buckets[i] = sum;
    sum += tmp;
  }
}

static void libsais_initialize_buckets_end_32s_1k(sa_sint_t k,
                                                  sa_sint_t* RESTRICT buckets) {
  fast_sint_t i;
  sa_sint_t sum = 0;
  for (i = 0; i <= (fast_sint_t)k - 1; i += 1) {
    sum += buckets[i];
    buckets[i] = sum;
  }
}

static sa_sint_t libsais_initialize_buckets_for_lms_suffixes_radix_sort_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT buckets,
    sa_sint_t first_lms_suffix) {
  {
    fast_uint_t f0 = 0;
    fast_uint_t f1 = 0;
    fast_sint_t c0 = T[first_lms_suffix];
    fast_sint_t c1 = 0;

    for (; --first_lms_suffix >= 0;) {
      c1 = c0;
      c0 = T[first_lms_suffix];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]--;
    }

    buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0)]--;
  }

  {
    sa_sint_t* RESTRICT temp_bucket = &buckets[4 * ALPHABET_SIZE];

    fast_sint_t i, j;
    sa_sint_t sum = 0;
    for (i = BUCKETS_INDEX4(0, 0), j = BUCKETS_INDEX2(0, 0);
         i <= BUCKETS_INDEX4(ALPHABET_SIZE - 1, 0);
         i += BUCKETS_INDEX4(1, 0), j += BUCKETS_INDEX2(1, 0)) {
      temp_bucket[j + BUCKETS_INDEX2(0, 1)] = sum;
      sum +=
          buckets[i + BUCKETS_INDEX4(0, 1)] + buckets[i + BUCKETS_INDEX4(0, 3)];
      temp_bucket[j] = sum;
    }

    return sum;
  }
}

static void libsais_initialize_buckets_for_lms_suffixes_radix_sort_32s_2k(
    const sa_sint_t* RESTRICT T, sa_sint_t k, sa_sint_t* RESTRICT buckets,
    sa_sint_t first_lms_suffix) {
  buckets[BUCKETS_INDEX2(T[first_lms_suffix], 0)]++;
  buckets[BUCKETS_INDEX2(T[first_lms_suffix], 1)]--;

  fast_sint_t i;
  sa_sint_t sum0 = 0, sum1 = 0;
  for (i = BUCKETS_INDEX2(0, 0); i <= BUCKETS_INDEX2((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX2(1, 0)) {
    sum0 +=
        buckets[i + BUCKETS_INDEX2(0, 0)] + buckets[i + BUCKETS_INDEX2(0, 1)];
    sum1 += buckets[i + BUCKETS_INDEX2(0, 1)];

    buckets[i + BUCKETS_INDEX2(0, 0)] = sum0;
    buckets[i + BUCKETS_INDEX2(0, 1)] = sum1;
  }
}

static sa_sint_t libsais_initialize_buckets_for_lms_suffixes_radix_sort_32s_6k(
    const sa_sint_t* RESTRICT T, sa_sint_t k, sa_sint_t* RESTRICT buckets,
    sa_sint_t first_lms_suffix) {
  {
    fast_uint_t f0 = 0;
    fast_uint_t f1 = 0;
    fast_sint_t c0 = T[first_lms_suffix];
    fast_sint_t c1 = 0;

    for (; --first_lms_suffix >= 0;) {
      c1 = c0;
      c0 = T[first_lms_suffix];
      f1 = f0;
      f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
      buckets[BUCKETS_INDEX4((fast_uint_t)c1, f1 + f1 + f0)]--;
    }

    buckets[BUCKETS_INDEX4((fast_uint_t)c0, f0 + f0)]--;
  }

  {
    sa_sint_t* RESTRICT temp_bucket = &buckets[4 * (fast_sint_t)k];

    fast_sint_t i, j;
    sa_sint_t sum = 0;
    for (i = BUCKETS_INDEX4(0, 0), j = 0;
         i <= BUCKETS_INDEX4((fast_sint_t)k - 1, 0);
         i += BUCKETS_INDEX4(1, 0), j += 1) {
      sum +=
          buckets[i + BUCKETS_INDEX4(0, 1)] + buckets[i + BUCKETS_INDEX4(0, 3)];
      temp_bucket[j] = sum;
    }

    return sum;
  }
}

static void libsais_initialize_buckets_for_radix_and_partial_sorting_32s_4k(
    const sa_sint_t* RESTRICT T, sa_sint_t k, sa_sint_t* RESTRICT buckets,
    sa_sint_t first_lms_suffix) {
  sa_sint_t* RESTRICT bucket_start = &buckets[2 * (fast_sint_t)k];
  sa_sint_t* RESTRICT bucket_end = &buckets[3 * (fast_sint_t)k];

  buckets[BUCKETS_INDEX2(T[first_lms_suffix], 0)]++;
  buckets[BUCKETS_INDEX2(T[first_lms_suffix], 1)]--;

  fast_sint_t i, j;
  sa_sint_t sum0 = 0, sum1 = 0;
  for (i = BUCKETS_INDEX2(0, 0), j = 0;
       i <= BUCKETS_INDEX2((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX2(1, 0), j += 1) {
    bucket_start[j] = sum1;

    sum0 += buckets[i + BUCKETS_INDEX2(0, 1)];
    sum1 +=
        buckets[i + BUCKETS_INDEX2(0, 0)] + buckets[i + BUCKETS_INDEX2(0, 1)];
    buckets[i + BUCKETS_INDEX2(0, 1)] = sum0;

    bucket_end[j] = sum1;
  }
}

static void libsais_radix_sort_lms_suffixes_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 3;
       i >= j; i -= 4) {
    libsais_prefetchr(&SA[i - 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - prefetch_distance - 0]]);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1]]);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 2]]);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 3]]);

    sa_sint_t p0 = SA[i - 0];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p0], 0)]] = p0;
    sa_sint_t p1 = SA[i - 1];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p1], 0)]] = p1;
    sa_sint_t p2 = SA[i - 2];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p2], 0)]] = p2;
    sa_sint_t p3 = SA[i - 3];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p3], 0)]] = p3;
  }

  for (j -= prefetch_distance + 3; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p], 0)]] = p;
  }
}

static void libsais_radix_sort_lms_suffixes_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    sa_sint_t flags, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (flags & LIBSAIS_FLAGS_GSA) {
    buckets[4 * ALPHABET_SIZE]--;
  }

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536 && \
                                                  m >= 65536 &&            \
                                                  omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_num_threads = 1;
#endif
    if (omp_num_threads == 1) {
      libsais_radix_sort_lms_suffixes_8u(T, SA, &buckets[4 * ALPHABET_SIZE],
                                         (fast_sint_t)n - (fast_sint_t)m + 1,
                                         (fast_sint_t)m - 1);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        sa_sint_t* RESTRICT src_bucket = &buckets[4 * ALPHABET_SIZE];
        sa_sint_t* RESTRICT dst_bucket =
            thread_state[omp_thread_num].state.buckets;

        fast_sint_t i, j;
        for (i = BUCKETS_INDEX2(0, 0), j = BUCKETS_INDEX4(0, 1);
             i <= BUCKETS_INDEX2(ALPHABET_SIZE - 1, 0);
             i += BUCKETS_INDEX2(1, 0), j += BUCKETS_INDEX4(1, 0)) {
          dst_bucket[i] = src_bucket[i] - dst_bucket[j];
        }
      }

      {
        fast_sint_t t, omp_block_start = 0,
                       omp_block_size = thread_state[omp_thread_num].state.m;
        for (t = omp_num_threads - 1; t >= omp_thread_num; --t)
          omp_block_start += thread_state[t].state.m;

        if (omp_block_start == (fast_sint_t)m && omp_block_size > 0) {
          omp_block_start -= 1;
          omp_block_size -= 1;
        }

        libsais_radix_sort_lms_suffixes_8u(
            T, SA, thread_state[omp_thread_num].state.buckets,
            (fast_sint_t)n - omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

static void libsais_radix_sort_lms_suffixes_32s_6k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + 2 * prefetch_distance + 3;
       i >= j; i -= 4) {
    libsais_prefetchr(&SA[i - 3 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 0]]);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 1]]);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 2]]);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 3]]);

    libsais_prefetchw(&induction_bucket[T[SA[i - prefetch_distance - 0]]]);
    libsais_prefetchw(&induction_bucket[T[SA[i - prefetch_distance - 1]]]);
    libsais_prefetchw(&induction_bucket[T[SA[i - prefetch_distance - 2]]]);
    libsais_prefetchw(&induction_bucket[T[SA[i - prefetch_distance - 3]]]);

    sa_sint_t p0 = SA[i - 0];
    SA[--induction_bucket[T[p0]]] = p0;
    sa_sint_t p1 = SA[i - 1];
    SA[--induction_bucket[T[p1]]] = p1;
    sa_sint_t p2 = SA[i - 2];
    SA[--induction_bucket[T[p2]]] = p2;
    sa_sint_t p3 = SA[i - 3];
    SA[--induction_bucket[T[p3]]] = p3;
  }

  for (j -= 2 * prefetch_distance + 3; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[--induction_bucket[T[p]]] = p;
  }
}

static void libsais_radix_sort_lms_suffixes_32s_2k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + 2 * prefetch_distance + 3;
       i >= j; i -= 4) {
    libsais_prefetchr(&SA[i - 3 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 0]]);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 1]]);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 2]]);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 3]]);

    libsais_prefetchw(
        &induction_bucket[BUCKETS_INDEX2(T[SA[i - prefetch_distance - 0]], 0)]);
    libsais_prefetchw(
        &induction_bucket[BUCKETS_INDEX2(T[SA[i - prefetch_distance - 1]], 0)]);
    libsais_prefetchw(
        &induction_bucket[BUCKETS_INDEX2(T[SA[i - prefetch_distance - 2]], 0)]);
    libsais_prefetchw(
        &induction_bucket[BUCKETS_INDEX2(T[SA[i - prefetch_distance - 3]], 0)]);

    sa_sint_t p0 = SA[i - 0];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p0], 0)]] = p0;
    sa_sint_t p1 = SA[i - 1];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p1], 0)]] = p1;
    sa_sint_t p2 = SA[i - 2];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p2], 0)]] = p2;
    sa_sint_t p3 = SA[i - 3];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p3], 0)]] = p3;
  }

  for (j -= 2 * prefetch_distance + 3; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[--induction_bucket[BUCKETS_INDEX2(T[p], 0)]] = p;
  }
}

#if defined(LIBSAIS_OPENMP)

static void libsais_radix_sort_lms_suffixes_32s_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i + prefetch_distance + 0]]);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1]]);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 2]]);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 3]]);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    cache[i + 0].symbol = T[cache[i + 0].index = SA[i + 0]];
    cache[i + 1].symbol = T[cache[i + 1].index = SA[i + 1]];
    cache[i + 2].symbol = T[cache[i + 2].index = SA[i + 2]];
    cache[i + 3].symbol = T[cache[i + 3].index = SA[i + 3]];
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    cache[i].symbol = T[cache[i].index = SA[i]];
  }
}

static void libsais_radix_sort_lms_suffixes_32s_6k_block_sort(
    sa_sint_t* RESTRICT induction_bucket, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 3;
       i >= j; i -= 4) {
    libsais_prefetchw(&cache[i - 2 * prefetch_distance]);

    libsais_prefetchw(
        &induction_bucket[cache[i - prefetch_distance - 0].symbol]);
    libsais_prefetchw(
        &induction_bucket[cache[i - prefetch_distance - 1].symbol]);
    libsais_prefetchw(
        &induction_bucket[cache[i - prefetch_distance - 2].symbol]);
    libsais_prefetchw(
        &induction_bucket[cache[i - prefetch_distance - 3].symbol]);

    cache[i - 0].symbol = --induction_bucket[cache[i - 0].symbol];
    cache[i - 1].symbol = --induction_bucket[cache[i - 1].symbol];
    cache[i - 2].symbol = --induction_bucket[cache[i - 2].symbol];
    cache[i - 3].symbol = --induction_bucket[cache[i - 3].symbol];
  }

  for (j -= prefetch_distance + 3; i >= j; i -= 1) {
    cache[i].symbol = --induction_bucket[cache[i].symbol];
  }
}

static void libsais_radix_sort_lms_suffixes_32s_2k_block_sort(
    sa_sint_t* RESTRICT induction_bucket, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 3;
       i >= j; i -= 4) {
    libsais_prefetchw(&cache[i - 2 * prefetch_distance]);

    libsais_prefetchw(&induction_bucket[BUCKETS_INDEX2(
        cache[i - prefetch_distance - 0].symbol, 0)]);
    libsais_prefetchw(&induction_bucket[BUCKETS_INDEX2(
        cache[i - prefetch_distance - 1].symbol, 0)]);
    libsais_prefetchw(&induction_bucket[BUCKETS_INDEX2(
        cache[i - prefetch_distance - 2].symbol, 0)]);
    libsais_prefetchw(&induction_bucket[BUCKETS_INDEX2(
        cache[i - prefetch_distance - 3].symbol, 0)]);

    cache[i - 0].symbol =
        --induction_bucket[BUCKETS_INDEX2(cache[i - 0].symbol, 0)];
    cache[i - 1].symbol =
        --induction_bucket[BUCKETS_INDEX2(cache[i - 1].symbol, 0)];
    cache[i - 2].symbol =
        --induction_bucket[BUCKETS_INDEX2(cache[i - 2].symbol, 0)];
    cache[i - 3].symbol =
        --induction_bucket[BUCKETS_INDEX2(cache[i - 3].symbol, 0)];
  }

  for (j -= prefetch_distance + 3; i >= j; i -= 1) {
    cache[i].symbol = --induction_bucket[BUCKETS_INDEX2(cache[i].symbol, 0)];
  }
}

static void libsais_radix_sort_lms_suffixes_32s_6k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_radix_sort_lms_suffixes_32s_6k(T, SA, induction_bucket,
                                             omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_radix_sort_lms_suffixes_32s_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_radix_sort_lms_suffixes_32s_6k_block_sort(
            induction_bucket, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_place_cached_suffixes(SA, cache - block_start, omp_block_start,
                                      omp_block_size);
      }
    }
#endif
  }
}

static void libsais_radix_sort_lms_suffixes_32s_2k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_radix_sort_lms_suffixes_32s_2k(T, SA, induction_bucket,
                                             omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_radix_sort_lms_suffixes_32s_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_radix_sort_lms_suffixes_32s_2k_block_sort(
            induction_bucket, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_place_cached_suffixes(SA, cache - block_start, omp_block_start,
                                      omp_block_size);
      }
    }
#endif
  }
}

#endif

static void libsais_radix_sort_lms_suffixes_32s_6k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t m, sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || m < 65536) {
    libsais_radix_sort_lms_suffixes_32s_6k(T, SA, induction_bucket,
                                           (fast_sint_t)n - (fast_sint_t)m + 1,
                                           (fast_sint_t)m - 1);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = 0; block_start < (fast_sint_t)m - 1;
         block_start = block_end) {
      block_end =
          block_start + (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end >= m) {
        block_end = (fast_sint_t)m - 1;
      }

      libsais_radix_sort_lms_suffixes_32s_6k_block_omp(
          T, SA, induction_bucket, thread_state[0].state.cache,
          (fast_sint_t)n - block_end, block_end - block_start, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif
}

static void libsais_radix_sort_lms_suffixes_32s_2k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t m, sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || m < 65536) {
    libsais_radix_sort_lms_suffixes_32s_2k(T, SA, induction_bucket,
                                           (fast_sint_t)n - (fast_sint_t)m + 1,
                                           (fast_sint_t)m - 1);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = 0; block_start < (fast_sint_t)m - 1;
         block_start = block_end) {
      block_end =
          block_start + (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end >= m) {
        block_end = (fast_sint_t)m - 1;
      }

      libsais_radix_sort_lms_suffixes_32s_2k_block_omp(
          T, SA, induction_bucket, thread_state[0].state.cache,
          (fast_sint_t)n - block_end, block_end - block_start, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif
}

static sa_sint_t libsais_radix_sort_lms_suffixes_32s_1k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t i = n - 2;
  sa_sint_t m = 0;
  fast_uint_t f0 = 1;
  fast_uint_t f1 = 0;
  fast_sint_t c0 = T[n - 1];
  fast_sint_t c1 = 0;
  fast_sint_t c2 = 0;

  for (; i >= prefetch_distance + 3; i -= 4) {
    libsais_prefetchr(&T[i - 2 * prefetch_distance]);

    libsais_prefetchw(&buckets[T[i - prefetch_distance - 0]]);
    libsais_prefetchw(&buckets[T[i - prefetch_distance - 1]]);
    libsais_prefetchw(&buckets[T[i - prefetch_distance - 2]]);
    libsais_prefetchw(&buckets[T[i - prefetch_distance - 3]]);

    c1 = T[i - 0];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    if (f1 & ~f0) {
      SA[--buckets[c2 = c0]] = i + 1;
      m++;
    }

    c0 = T[i - 1];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    if (f0 & ~f1) {
      SA[--buckets[c2 = c1]] = i - 0;
      m++;
    }

    c1 = T[i - 2];
    f1 = (fast_uint_t)(c1 > (c0 - (fast_sint_t)(f0)));
    if (f1 & ~f0) {
      SA[--buckets[c2 = c0]] = i - 1;
      m++;
    }

    c0 = T[i - 3];
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    if (f0 & ~f1) {
      SA[--buckets[c2 = c1]] = i - 2;
      m++;
    }
  }

  for (; i >= 0; i -= 1) {
    c1 = c0;
    c0 = T[i];
    f1 = f0;
    f0 = (fast_uint_t)(c0 > (c1 - (fast_sint_t)(f1)));
    if (f0 & ~f1) {
      SA[--buckets[c2 = c1]] = i + 1;
      m++;
    }
  }

  if (m > 1) {
    SA[buckets[c2]] = 0;
  }

  return m;
}

static void libsais_radix_sort_set_markers_32s_6k(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT induction_bucket,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&induction_bucket[i + 2 * prefetch_distance]);

    libsais_prefetchw(&SA[induction_bucket[i + prefetch_distance + 0]]);
    libsais_prefetchw(&SA[induction_bucket[i + prefetch_distance + 1]]);
    libsais_prefetchw(&SA[induction_bucket[i + prefetch_distance + 2]]);
    libsais_prefetchw(&SA[induction_bucket[i + prefetch_distance + 3]]);

    SA[induction_bucket[i + 0]] |= SAINT_MIN;
    SA[induction_bucket[i + 1]] |= SAINT_MIN;
    SA[induction_bucket[i + 2]] |= SAINT_MIN;
    SA[induction_bucket[i + 3]] |= SAINT_MIN;
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    SA[induction_bucket[i]] |= SAINT_MIN;
  }
}

static void libsais_radix_sort_set_markers_32s_4k(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT induction_bucket,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(
        &induction_bucket[BUCKETS_INDEX2(i + 2 * prefetch_distance, 0)]);

    libsais_prefetchw(
        &SA[induction_bucket[BUCKETS_INDEX2(i + prefetch_distance + 0, 0)]]);
    libsais_prefetchw(
        &SA[induction_bucket[BUCKETS_INDEX2(i + prefetch_distance + 1, 0)]]);
    libsais_prefetchw(
        &SA[induction_bucket[BUCKETS_INDEX2(i + prefetch_distance + 2, 0)]]);
    libsais_prefetchw(
        &SA[induction_bucket[BUCKETS_INDEX2(i + prefetch_distance + 3, 0)]]);

    SA[induction_bucket[BUCKETS_INDEX2(i + 0, 0)]] |= SUFFIX_GROUP_MARKER;
    SA[induction_bucket[BUCKETS_INDEX2(i + 1, 0)]] |= SUFFIX_GROUP_MARKER;
    SA[induction_bucket[BUCKETS_INDEX2(i + 2, 0)]] |= SUFFIX_GROUP_MARKER;
    SA[induction_bucket[BUCKETS_INDEX2(i + 3, 0)]] |= SUFFIX_GROUP_MARKER;
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    SA[induction_bucket[BUCKETS_INDEX2(i, 0)]] |= SUFFIX_GROUP_MARKER;
  }
}

static void libsais_radix_sort_set_markers_32s_6k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t k, sa_sint_t* RESTRICT induction_bucket,
    sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && k >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
    fast_sint_t omp_block_stride =
        (((fast_sint_t)k - 1) / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : (fast_sint_t)k - 1 - omp_block_start;
#else
    UNUSED(threads);

    fast_sint_t omp_block_start = 0;
    fast_sint_t omp_block_size = (fast_sint_t)k - 1;
#endif

    libsais_radix_sort_set_markers_32s_6k(SA, induction_bucket, omp_block_start,
                                          omp_block_size);
  }
}

static void libsais_radix_sort_set_markers_32s_4k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t k, sa_sint_t* RESTRICT induction_bucket,
    sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && k >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
    fast_sint_t omp_block_stride =
        (((fast_sint_t)k - 1) / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : (fast_sint_t)k - 1 - omp_block_start;
#else
    UNUSED(threads);

    fast_sint_t omp_block_start = 0;
    fast_sint_t omp_block_size = (fast_sint_t)k - 1;
#endif

    libsais_radix_sort_set_markers_32s_4k(SA, induction_bucket, omp_block_start,
                                          omp_block_size);
  }
}

static void libsais_initialize_buckets_for_partial_sorting_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT buckets,
    sa_sint_t first_lms_suffix, sa_sint_t left_suffixes_count) {
  sa_sint_t* RESTRICT temp_bucket = &buckets[4 * ALPHABET_SIZE];

  buckets[BUCKETS_INDEX4((fast_uint_t)T[first_lms_suffix], 1)]++;

  fast_sint_t i, j;
  sa_sint_t sum0 = left_suffixes_count + 1, sum1 = 0;
  for (i = BUCKETS_INDEX4(0, 0), j = BUCKETS_INDEX2(0, 0);
       i <= BUCKETS_INDEX4(ALPHABET_SIZE - 1, 0);
       i += BUCKETS_INDEX4(1, 0), j += BUCKETS_INDEX2(1, 0)) {
    temp_bucket[j + BUCKETS_INDEX2(0, 0)] = sum0;

    sum0 +=
        buckets[i + BUCKETS_INDEX4(0, 0)] + buckets[i + BUCKETS_INDEX4(0, 2)];
    sum1 += buckets[i + BUCKETS_INDEX4(0, 1)];

    buckets[j + BUCKETS_INDEX2(0, 0)] = sum0;
    buckets[j + BUCKETS_INDEX2(0, 1)] = sum1;
  }
}

static void libsais_initialize_buckets_for_partial_sorting_32s_6k(
    const sa_sint_t* RESTRICT T, sa_sint_t k, sa_sint_t* RESTRICT buckets,
    sa_sint_t first_lms_suffix, sa_sint_t left_suffixes_count) {
  sa_sint_t* RESTRICT temp_bucket = &buckets[4 * (fast_sint_t)k];

  fast_sint_t i, j;
  sa_sint_t sum0 = left_suffixes_count + 1, sum1 = 0, sum2 = 0;
  for (first_lms_suffix = T[first_lms_suffix], i = BUCKETS_INDEX4(0, 0),
      j = BUCKETS_INDEX2(0, 0);
       i != BUCKETS_INDEX4((fast_sint_t)first_lms_suffix, 0);
       i += BUCKETS_INDEX4(1, 0), j += BUCKETS_INDEX2(1, 0)) {
    sa_sint_t SS = buckets[i + BUCKETS_INDEX4(0, 0)];
    sa_sint_t LS = buckets[i + BUCKETS_INDEX4(0, 1)];
    sa_sint_t SL = buckets[i + BUCKETS_INDEX4(0, 2)];
    sa_sint_t LL = buckets[i + BUCKETS_INDEX4(0, 3)];

    buckets[i + BUCKETS_INDEX4(0, 0)] = sum0;
    buckets[i + BUCKETS_INDEX4(0, 1)] = sum2;
    buckets[i + BUCKETS_INDEX4(0, 2)] = 0;
    buckets[i + BUCKETS_INDEX4(0, 3)] = 0;

    sum0 += SS + SL;
    sum1 += LS;
    sum2 += LS + LL;

    temp_bucket[j + BUCKETS_INDEX2(0, 0)] = sum0;
    temp_bucket[j + BUCKETS_INDEX2(0, 1)] = sum1;
  }

  for (sum1 += 1; i <= BUCKETS_INDEX4((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX4(1, 0), j += BUCKETS_INDEX2(1, 0)) {
    sa_sint_t SS = buckets[i + BUCKETS_INDEX4(0, 0)];
    sa_sint_t LS = buckets[i + BUCKETS_INDEX4(0, 1)];
    sa_sint_t SL = buckets[i + BUCKETS_INDEX4(0, 2)];
    sa_sint_t LL = buckets[i + BUCKETS_INDEX4(0, 3)];

    buckets[i + BUCKETS_INDEX4(0, 0)] = sum0;
    buckets[i + BUCKETS_INDEX4(0, 1)] = sum2;
    buckets[i + BUCKETS_INDEX4(0, 2)] = 0;
    buckets[i + BUCKETS_INDEX4(0, 3)] = 0;

    sum0 += SS + SL;
    sum1 += LS;
    sum2 += LS + LL;

    temp_bucket[j + BUCKETS_INDEX2(0, 0)] = sum0;
    temp_bucket[j + BUCKETS_INDEX2(0, 1)] = sum1;
  }
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[4 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = SA[i + 0];
    d += (p0 < 0);
    p0 &= SAINT_MAX;
    sa_sint_t v0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] >= T[p0 - 1]);
    SA[induction_bucket[v0]++] =
        (p0 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v0] != d) << (SAINT_BIT - 1));
    distinct_names[v0] = d;

    sa_sint_t p1 = SA[i + 1];
    d += (p1 < 0);
    p1 &= SAINT_MAX;
    sa_sint_t v1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] >= T[p1 - 1]);
    SA[induction_bucket[v1]++] =
        (p1 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v1] != d) << (SAINT_BIT - 1));
    distinct_names[v1] = d;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] >= T[p - 1]);
    SA[induction_bucket[v]++] =
        (p - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v] != d) << (SAINT_BIT - 1));
    distinct_names[v] = d;
  }

  return d;
}

#if defined(LIBSAIS_OPENMP)

static void libsais_partial_sorting_scan_left_to_right_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size,
    LIBSAIS_THREAD_STATE* RESTRICT state) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  memset(induction_bucket, 0, (size_t)2 * (size_t)k * sizeof(sa_sint_t));
  memset(distinct_names, 0, (size_t)2 * (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  sa_sint_t d = 1;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = cache[count].index = SA[i + 0];
    d += (p0 < 0);
    p0 &= SAINT_MAX;
    sa_sint_t v0 = cache[count++].symbol =
        BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] >= T[p0 - 1]);
    induction_bucket[v0]++;
    distinct_names[v0] = d;
    sa_sint_t p1 = cache[count].index = SA[i + 1];
    d += (p1 < 0);
    p1 &= SAINT_MAX;
    sa_sint_t v1 = cache[count++].symbol =
        BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] >= T[p1 - 1]);
    induction_bucket[v1]++;
    distinct_names[v1] = d;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = cache[count].index = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = cache[count++].symbol =
        BUCKETS_INDEX2(T[p - 1], T[p - 2] >= T[p - 1]);
    induction_bucket[v]++;
    distinct_names[v] = d;
  }

  state[0].state.position = (fast_sint_t)d - 1;
  state[0].state.count = count;
}

static void libsais_partial_sorting_scan_left_to_right_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT buckets,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t count, sa_sint_t d) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  fast_sint_t i, j;
  for (i = 0, j = count - 1; i < j; i += 2) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    sa_sint_t p0 = cache[i + 0].index;
    d += (p0 < 0);
    sa_sint_t v0 = cache[i + 0].symbol;
    SA[induction_bucket[v0]++] =
        (p0 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v0] != d) << (SAINT_BIT - 1));
    distinct_names[v0] = d;

    sa_sint_t p1 = cache[i + 1].index;
    d += (p1 < 0);
    sa_sint_t v1 = cache[i + 1].symbol;
    SA[induction_bucket[v1]++] =
        (p1 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v1] != d) << (SAINT_BIT - 1));
    distinct_names[v1] = d;
  }

  for (j += 1; i < j; i += 1) {
    sa_sint_t p = cache[i].index;
    d += (p < 0);
    sa_sint_t v = cache[i].symbol;
    SA[induction_bucket[v]++] =
        (p - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v] != d) << (SAINT_BIT - 1));
    distinct_names[v] = d;
  }
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_sorting_scan_left_to_right_8u(
          T, SA, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_left_to_right_8u_block_prepare(
            T, SA, k, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache, omp_block_start,
            omp_block_size, &thread_state[omp_thread_num]);
      }

#pragma omp barrier

#pragma omp master
      {
        sa_sint_t* RESTRICT induction_bucket = &buckets[4 * ALPHABET_SIZE];
        sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

        fast_sint_t t;
        for (t = 0; t < omp_num_threads; ++t) {
          sa_sint_t* RESTRICT temp_induction_bucket =
              &thread_state[t].state.buckets[0 * ALPHABET_SIZE];
          sa_sint_t* RESTRICT temp_distinct_names =
              &thread_state[t].state.buckets[2 * ALPHABET_SIZE];

          fast_sint_t c;
          for (c = 0; c < 2 * k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_induction_bucket[c];
            induction_bucket[c] = A + B;
            temp_induction_bucket[c] = A;
          }

          for (d -= 1, c = 0; c < 2 * k; c += 1) {
            sa_sint_t A = distinct_names[c], B = temp_distinct_names[c],
                      D = B + d;
            distinct_names[c] = B > 0 ? D : A;
            temp_distinct_names[c] = A;
          }
          d += 1 + (sa_sint_t)thread_state[t].state.position;
          thread_state[t].state.position =
              (fast_sint_t)d - thread_state[t].state.position;
        }
      }

#pragma omp barrier

      {
        libsais_partial_sorting_scan_left_to_right_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count,
            (sa_sint_t)thread_state[omp_thread_num].state.position);
      }
    }
#endif
  }

  return d;
}

#endif

static sa_sint_t libsais_partial_sorting_scan_left_to_right_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t left_suffixes_count, sa_sint_t d,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t* RESTRICT induction_bucket = &buckets[4 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  SA[induction_bucket[BUCKETS_INDEX2(T[n - 1], T[n - 2] >= T[n - 1])]++] =
      (n - 1) | SAINT_MIN;
  distinct_names[BUCKETS_INDEX2(T[n - 1], T[n - 2] >= T[n - 1])] = ++d;

  if (threads == 1 || left_suffixes_count < 65536) {
    d = libsais_partial_sorting_scan_left_to_right_8u(T, SA, buckets, d, 0,
                                                      left_suffixes_count);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = 0; block_start < left_suffixes_count;) {
      if (SA[block_start] == 0) {
        block_start++;
      } else {
        fast_sint_t block_max_end =
            block_start +
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end > left_suffixes_count) {
          block_max_end = left_suffixes_count;
        }
        fast_sint_t block_end = block_start + 1;
        while (block_end < block_max_end && SA[block_end] != 0) {
          block_end++;
        }
        fast_sint_t block_size = block_end - block_start;

        if (block_size < 32) {
          for (; block_start < block_end; block_start += 1) {
            sa_sint_t p = SA[block_start];
            d += (p < 0);
            p &= SAINT_MAX;
            sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] >= T[p - 1]);
            SA[induction_bucket[v]++] =
                (p - 1) | (sa_sint_t)((sa_uint_t)(distinct_names[v] != d)
                                      << (SAINT_BIT - 1));
            distinct_names[v] = d;
          }
        } else {
          d = libsais_partial_sorting_scan_left_to_right_8u_block_omp(
              T, SA, k, buckets, d, block_start, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_6k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - 2 * prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchr(&SA[i + 3 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i + 2 * prefetch_distance + 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + 2 * prefetch_distance + 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i + 2 * prefetch_distance + 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + 2 * prefetch_distance + 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = SA[i + prefetch_distance + 0] & SAINT_MAX;
    sa_sint_t v0 = BUCKETS_INDEX4(T[p0 - (p0 > 0)], 0);
    libsais_prefetchw(&buckets[v0]);
    sa_sint_t p1 = SA[i + prefetch_distance + 1] & SAINT_MAX;
    sa_sint_t v1 = BUCKETS_INDEX4(T[p1 - (p1 > 0)], 0);
    libsais_prefetchw(&buckets[v1]);

    sa_sint_t p2 = SA[i + 0];
    d += (p2 < 0);
    p2 &= SAINT_MAX;
    sa_sint_t v2 = BUCKETS_INDEX4(T[p2 - 1], T[p2 - 2] >= T[p2 - 1]);
    SA[buckets[v2]++] = (p2 - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v2] != d)
                                               << (SAINT_BIT - 1));
    buckets[2 + v2] = d;

    sa_sint_t p3 = SA[i + 1];
    d += (p3 < 0);
    p3 &= SAINT_MAX;
    sa_sint_t v3 = BUCKETS_INDEX4(T[p3 - 1], T[p3 - 2] >= T[p3 - 1]);
    SA[buckets[v3]++] = (p3 - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v3] != d)
                                               << (SAINT_BIT - 1));
    buckets[2 + v3] = d;
  }

  for (j += 2 * prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = BUCKETS_INDEX4(T[p - 1], T[p - 2] >= T[p - 1]);
    SA[buckets[v]++] = (p - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v] != d)
                                             << (SAINT_BIT - 1));
    buckets[2 + v] = d;
  }

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_4k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[2 * (fast_sint_t)k];
  sa_sint_t* RESTRICT distinct_names = &buckets[0 * (fast_sint_t)k];

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - 2 * prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 3 * prefetch_distance]);

    sa_sint_t s0 = SA[i + 2 * prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + 2 * prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);
    sa_sint_t s2 = SA[i + 1 * prefetch_distance + 0];
    if (s2 > 0) {
      const fast_sint_t Ts2 = T[(s2 & ~SUFFIX_GROUP_MARKER) - 1];
      libsais_prefetchw(&induction_bucket[Ts2]);
      libsais_prefetchw(&distinct_names[BUCKETS_INDEX2(Ts2, 0)]);
    }
    sa_sint_t s3 = SA[i + 1 * prefetch_distance + 1];
    if (s3 > 0) {
      const fast_sint_t Ts3 = T[(s3 & ~SUFFIX_GROUP_MARKER) - 1];
      libsais_prefetchw(&induction_bucket[Ts3]);
      libsais_prefetchw(&distinct_names[BUCKETS_INDEX2(Ts3, 0)]);
    }

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      SA[i + 0] = 0;
      d += (p0 >> (SUFFIX_GROUP_BIT - 1));
      p0 &= ~SUFFIX_GROUP_MARKER;
      sa_sint_t v0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] < T[p0 - 1]);
      SA[induction_bucket[T[p0 - 1]]++] =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p0 - 2] < T[p0 - 1]) << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v0] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v0] = d;
    }

    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      SA[i + 1] = 0;
      d += (p1 >> (SUFFIX_GROUP_BIT - 1));
      p1 &= ~SUFFIX_GROUP_MARKER;
      sa_sint_t v1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] < T[p1 - 1]);
      SA[induction_bucket[T[p1 - 1]]++] =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p1 - 2] < T[p1 - 1]) << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v1] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v1] = d;
    }
  }

  for (j += 2 * prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      SA[i] = 0;
      d += (p >> (SUFFIX_GROUP_BIT - 1));
      p &= ~SUFFIX_GROUP_MARKER;
      sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] < T[p - 1]);
      SA[induction_bucket[T[p - 1]]++] =
          (p - 1) |
          (sa_sint_t)((sa_uint_t)(T[p - 2] < T[p - 1]) << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v] = d;
    }
  }

  return d;
}

static void libsais_partial_sorting_scan_left_to_right_32s_1k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - 2 * prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 3 * prefetch_distance]);

    sa_sint_t s0 = SA[i + 2 * prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 1];
    libsais_prefetchr(Ts0 - 1);
    sa_sint_t s1 = SA[i + 2 * prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 1];
    libsais_prefetchr(Ts1 - 1);
    sa_sint_t s2 = SA[i + 1 * prefetch_distance + 0];
    if (s2 > 0) {
      libsais_prefetchw(&induction_bucket[T[s2 - 1]]);
      libsais_prefetchr(&T[s2] - 2);
    }
    sa_sint_t s3 = SA[i + 1 * prefetch_distance + 1];
    if (s3 > 0) {
      libsais_prefetchw(&induction_bucket[T[s3 - 1]]);
      libsais_prefetchr(&T[s3] - 2);
    }

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      SA[i + 0] = 0;
      SA[induction_bucket[T[p0 - 1]]++] =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p0 - 2] < T[p0 - 1]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      SA[i + 1] = 0;
      SA[induction_bucket[T[p1 - 1]]++] =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p1 - 2] < T[p1 - 1]) << (SAINT_BIT - 1));
    }
  }

  for (j += 2 * prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      SA[i] = 0;
      SA[induction_bucket[T[p - 1]]++] =
          (p - 1) |
          (sa_sint_t)((sa_uint_t)(T[p - 2] < T[p - 1]) << (SAINT_BIT - 1));
    }
  }
}

#if defined(LIBSAIS_OPENMP)

static void libsais_partial_sorting_scan_left_to_right_32s_6k_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t p0 = cache[i + 0].index = SA[i + 0];
    sa_sint_t symbol0 = 0;
    p0 &= SAINT_MAX;
    if (p0 != 0) {
      symbol0 = BUCKETS_INDEX4(T[p0 - 1], T[p0 - 2] >= T[p0 - 1]);
    }
    cache[i + 0].symbol = symbol0;
    sa_sint_t p1 = cache[i + 1].index = SA[i + 1];
    sa_sint_t symbol1 = 0;
    p1 &= SAINT_MAX;
    if (p1 != 0) {
      symbol1 = BUCKETS_INDEX4(T[p1 - 1], T[p1 - 2] >= T[p1 - 1]);
    }
    cache[i + 1].symbol = symbol1;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = cache[i].index = SA[i];
    sa_sint_t symbol = 0;
    p &= SAINT_MAX;
    if (p != 0) {
      symbol = BUCKETS_INDEX4(T[p - 1], T[p - 2] >= T[p - 1]);
    }
    cache[i].symbol = symbol;
  }
}

static void libsais_partial_sorting_scan_left_to_right_32s_4k_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t symbol0 = SAINT_MIN, p0 = SA[i + 0];
    if (p0 > 0) {
      cache[i + 0].index = p0;
      p0 &= ~SUFFIX_GROUP_MARKER;
      symbol0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] < T[p0 - 1]);
      p0 = 0;
    }
    cache[i + 0].symbol = symbol0;
    SA[i + 0] = p0 & SAINT_MAX;
    sa_sint_t symbol1 = SAINT_MIN, p1 = SA[i + 1];
    if (p1 > 0) {
      cache[i + 1].index = p1;
      p1 &= ~SUFFIX_GROUP_MARKER;
      symbol1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] < T[p1 - 1]);
      p1 = 0;
    }
    cache[i + 1].symbol = symbol1;
    SA[i + 1] = p1 & SAINT_MAX;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t symbol = SAINT_MIN, p = SA[i];
    if (p > 0) {
      cache[i].index = p;
      p &= ~SUFFIX_GROUP_MARKER;
      symbol = BUCKETS_INDEX2(T[p - 1], T[p - 2] < T[p - 1]);
      p = 0;
    }
    cache[i].symbol = symbol;
    SA[i] = p & SAINT_MAX;
  }
}

static void libsais_partial_sorting_scan_left_to_right_32s_1k_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t symbol0 = SAINT_MIN, p0 = SA[i + 0];
    if (p0 > 0) {
      cache[i + 0].index =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p0 - 2] < T[p0 - 1]) << (SAINT_BIT - 1));
      symbol0 = T[p0 - 1];
      p0 = 0;
    }
    cache[i + 0].symbol = symbol0;
    SA[i + 0] = p0 & SAINT_MAX;
    sa_sint_t symbol1 = SAINT_MIN, p1 = SA[i + 1];
    if (p1 > 0) {
      cache[i + 1].index =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p1 - 2] < T[p1 - 1]) << (SAINT_BIT - 1));
      symbol1 = T[p1 - 1];
      p1 = 0;
    }
    cache[i + 1].symbol = symbol1;
    SA[i + 1] = p1 & SAINT_MAX;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t symbol = SAINT_MIN, p = SA[i];
    if (p > 0) {
      cache[i].index = (p - 1) | (sa_sint_t)((sa_uint_t)(T[p - 2] < T[p - 1])
                                             << (SAINT_BIT - 1));
      symbol = T[p - 1];
      p = 0;
    }
    cache[i].symbol = symbol;
    SA[i] = p & SAINT_MAX;
  }
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_6k_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT buckets, sa_sint_t d,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, omp_block_end = omp_block_start + omp_block_size;
  for (i = omp_block_start, j = omp_block_end - prefetch_distance - 1; i < j;
       i += 2) {
    libsais_prefetchw(&cache[i + 2 * prefetch_distance]);

    libsais_prefetchw(&buckets[cache[i + prefetch_distance + 0].symbol]);
    libsais_prefetchw(&buckets[cache[i + prefetch_distance + 1].symbol]);

    sa_sint_t v0 = cache[i + 0].symbol, p0 = cache[i + 0].index;
    d += (p0 < 0);
    cache[i + 0].symbol = buckets[v0]++;
    cache[i + 0].index =
        (p0 - 1) |
        (sa_sint_t)((sa_uint_t)(buckets[2 + v0] != d) << (SAINT_BIT - 1));
    buckets[2 + v0] = d;
    if (cache[i + 0].symbol < omp_block_end) {
      sa_sint_t s = cache[i + 0].symbol,
                q = (cache[s].index = cache[i + 0].index) & SAINT_MAX;
      cache[s].symbol = BUCKETS_INDEX4(T[q - 1], T[q - 2] >= T[q - 1]);
    }

    sa_sint_t v1 = cache[i + 1].symbol, p1 = cache[i + 1].index;
    d += (p1 < 0);
    cache[i + 1].symbol = buckets[v1]++;
    cache[i + 1].index =
        (p1 - 1) |
        (sa_sint_t)((sa_uint_t)(buckets[2 + v1] != d) << (SAINT_BIT - 1));
    buckets[2 + v1] = d;
    if (cache[i + 1].symbol < omp_block_end) {
      sa_sint_t s = cache[i + 1].symbol,
                q = (cache[s].index = cache[i + 1].index) & SAINT_MAX;
      cache[s].symbol = BUCKETS_INDEX4(T[q - 1], T[q - 2] >= T[q - 1]);
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t v = cache[i].symbol, p = cache[i].index;
    d += (p < 0);
    cache[i].symbol = buckets[v]++;
    cache[i].index = (p - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v] != d)
                                           << (SAINT_BIT - 1));
    buckets[2 + v] = d;
    if (cache[i].symbol < omp_block_end) {
      sa_sint_t s = cache[i].symbol,
                q = (cache[s].index = cache[i].index) & SAINT_MAX;
      cache[s].symbol = BUCKETS_INDEX4(T[q - 1], T[q - 2] >= T[q - 1]);
    }
  }

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_4k_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t k, sa_sint_t* RESTRICT buckets,
    sa_sint_t d, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[2 * (fast_sint_t)k];
  sa_sint_t* RESTRICT distinct_names = &buckets[0 * (fast_sint_t)k];

  fast_sint_t i, j, omp_block_end = omp_block_start + omp_block_size;
  for (i = omp_block_start, j = omp_block_end - prefetch_distance - 1; i < j;
       i += 2) {
    libsais_prefetchw(&cache[i + 2 * prefetch_distance]);

    sa_sint_t s0 = cache[i + prefetch_distance + 0].symbol;
    const sa_sint_t* Is0 = &induction_bucket[s0 > 0 ? s0 >> 1 : 0];
    libsais_prefetchw(Is0);
    const sa_sint_t* Ds0 = &distinct_names[s0 > 0 ? s0 : 0];
    libsais_prefetchw(Ds0);
    sa_sint_t s1 = cache[i + prefetch_distance + 1].symbol;
    const sa_sint_t* Is1 = &induction_bucket[s1 > 0 ? s1 >> 1 : 0];
    libsais_prefetchw(Is1);
    const sa_sint_t* Ds1 = &distinct_names[s1 > 0 ? s1 : 0];
    libsais_prefetchw(Ds1);

    sa_sint_t v0 = cache[i + 0].symbol;
    if (v0 >= 0) {
      sa_sint_t p0 = cache[i + 0].index;
      d += (p0 >> (SUFFIX_GROUP_BIT - 1));
      cache[i + 0].symbol = induction_bucket[v0 >> 1]++;
      cache[i + 0].index =
          (p0 - 1) | (sa_sint_t)((sa_uint_t)v0 << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v0] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v0] = d;
      if (cache[i + 0].symbol < omp_block_end) {
        sa_sint_t ni = cache[i + 0].symbol, np = cache[i + 0].index;
        if (np > 0) {
          cache[ni].index = np;
          np &= ~SUFFIX_GROUP_MARKER;
          cache[ni].symbol = BUCKETS_INDEX2(T[np - 1], T[np - 2] < T[np - 1]);
          np = 0;
        }
        cache[i + 0].index = np & SAINT_MAX;
      }
    }

    sa_sint_t v1 = cache[i + 1].symbol;
    if (v1 >= 0) {
      sa_sint_t p1 = cache[i + 1].index;
      d += (p1 >> (SUFFIX_GROUP_BIT - 1));
      cache[i + 1].symbol = induction_bucket[v1 >> 1]++;
      cache[i + 1].index =
          (p1 - 1) | (sa_sint_t)((sa_uint_t)v1 << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v1] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v1] = d;
      if (cache[i + 1].symbol < omp_block_end) {
        sa_sint_t ni = cache[i + 1].symbol, np = cache[i + 1].index;
        if (np > 0) {
          cache[ni].index = np;
          np &= ~SUFFIX_GROUP_MARKER;
          cache[ni].symbol = BUCKETS_INDEX2(T[np - 1], T[np - 2] < T[np - 1]);
          np = 0;
        }
        cache[i + 1].index = np & SAINT_MAX;
      }
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t v = cache[i].symbol;
    if (v >= 0) {
      sa_sint_t p = cache[i].index;
      d += (p >> (SUFFIX_GROUP_BIT - 1));
      cache[i].symbol = induction_bucket[v >> 1]++;
      cache[i].index =
          (p - 1) | (sa_sint_t)((sa_uint_t)v << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v] = d;
      if (cache[i].symbol < omp_block_end) {
        sa_sint_t ni = cache[i].symbol, np = cache[i].index;
        if (np > 0) {
          cache[ni].index = np;
          np &= ~SUFFIX_GROUP_MARKER;
          cache[ni].symbol = BUCKETS_INDEX2(T[np - 1], T[np - 2] < T[np - 1]);
          np = 0;
        }
        cache[i].index = np & SAINT_MAX;
      }
    }
  }

  return d;
}

static void libsais_partial_sorting_scan_left_to_right_32s_1k_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT induction_bucket,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, omp_block_end = omp_block_start + omp_block_size;
  for (i = omp_block_start, j = omp_block_end - prefetch_distance - 1; i < j;
       i += 2) {
    libsais_prefetchw(&cache[i + 2 * prefetch_distance]);

    sa_sint_t s0 = cache[i + prefetch_distance + 0].symbol;
    const sa_sint_t* Is0 = &induction_bucket[s0 > 0 ? s0 : 0];
    libsais_prefetchw(Is0);
    sa_sint_t s1 = cache[i + prefetch_distance + 1].symbol;
    const sa_sint_t* Is1 = &induction_bucket[s1 > 0 ? s1 : 0];
    libsais_prefetchw(Is1);

    sa_sint_t v0 = cache[i + 0].symbol;
    if (v0 >= 0) {
      cache[i + 0].symbol = induction_bucket[v0]++;
      if (cache[i + 0].symbol < omp_block_end) {
        sa_sint_t ni = cache[i + 0].symbol, np = cache[i + 0].index;
        if (np > 0) {
          cache[ni].index =
              (np - 1) | (sa_sint_t)((sa_uint_t)(T[np - 2] < T[np - 1])
                                     << (SAINT_BIT - 1));
          cache[ni].symbol = T[np - 1];
          np = 0;
        }
        cache[i + 0].index = np & SAINT_MAX;
      }
    }

    sa_sint_t v1 = cache[i + 1].symbol;
    if (v1 >= 0) {
      cache[i + 1].symbol = induction_bucket[v1]++;
      if (cache[i + 1].symbol < omp_block_end) {
        sa_sint_t ni = cache[i + 1].symbol, np = cache[i + 1].index;
        if (np > 0) {
          cache[ni].index =
              (np - 1) | (sa_sint_t)((sa_uint_t)(T[np - 2] < T[np - 1])
                                     << (SAINT_BIT - 1));
          cache[ni].symbol = T[np - 1];
          np = 0;
        }
        cache[i + 1].index = np & SAINT_MAX;
      }
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t v = cache[i].symbol;
    if (v >= 0) {
      cache[i].symbol = induction_bucket[v]++;
      if (cache[i].symbol < omp_block_end) {
        sa_sint_t ni = cache[i].symbol, np = cache[i].index;
        if (np > 0) {
          cache[ni].index =
              (np - 1) | (sa_sint_t)((sa_uint_t)(T[np - 2] < T[np - 1])
                                     << (SAINT_BIT - 1));
          cache[ni].symbol = T[np - 1];
          np = 0;
        }
        cache[i].index = np & SAINT_MAX;
      }
    }
  }
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_6k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_sorting_scan_left_to_right_32s_6k(
          T, SA, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_left_to_right_32s_6k_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        d = libsais_partial_sorting_scan_left_to_right_32s_6k_block_sort(
            T, buckets, d, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_place_cached_suffixes(SA, cache - block_start, omp_block_start,
                                      omp_block_size);
      }
    }
#endif
  }

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_4k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_sorting_scan_left_to_right_32s_4k(
          T, SA, k, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_left_to_right_32s_4k_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        d = libsais_partial_sorting_scan_left_to_right_32s_4k_block_sort(
            T, k, buckets, d, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_compact_and_place_cached_suffixes(
            SA, cache - block_start, omp_block_start, omp_block_size);
      }
    }
#endif
  }

  return d;
}

static void libsais_partial_sorting_scan_left_to_right_32s_1k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_partial_sorting_scan_left_to_right_32s_1k(
          T, SA, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_left_to_right_32s_1k_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_partial_sorting_scan_left_to_right_32s_1k_block_sort(
            T, buckets, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_compact_and_place_cached_suffixes(
            SA, cache - block_start, omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

#endif

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_6k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets, sa_sint_t left_suffixes_count, sa_sint_t d,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  SA[buckets[BUCKETS_INDEX4(T[n - 1], T[n - 2] >= T[n - 1])]++] =
      (n - 1) | SAINT_MIN;
  buckets[2 + BUCKETS_INDEX4(T[n - 1], T[n - 2] >= T[n - 1])] = ++d;

  if (threads == 1 || left_suffixes_count < 65536) {
    d = libsais_partial_sorting_scan_left_to_right_32s_6k(T, SA, buckets, d, 0,
                                                          left_suffixes_count);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = 0; block_start < left_suffixes_count;
         block_start = block_end) {
      block_end =
          block_start + (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end > left_suffixes_count) {
        block_end = left_suffixes_count;
      }

      d = libsais_partial_sorting_scan_left_to_right_32s_6k_block_omp(
          T, SA, buckets, d, thread_state[0].state.cache, block_start,
          block_end - block_start, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_left_to_right_32s_4k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t d, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t* RESTRICT induction_bucket = &buckets[2 * (fast_sint_t)k];
  sa_sint_t* RESTRICT distinct_names = &buckets[0 * (fast_sint_t)k];

  SA[induction_bucket[T[n - 1]]++] =
      (n - 1) |
      (sa_sint_t)((sa_uint_t)(T[n - 2] < T[n - 1]) << (SAINT_BIT - 1)) |
      SUFFIX_GROUP_MARKER;
  distinct_names[BUCKETS_INDEX2(T[n - 1], T[n - 2] < T[n - 1])] = ++d;

  if (threads == 1 || n < 65536) {
    d = libsais_partial_sorting_scan_left_to_right_32s_4k(T, SA, k, buckets, d,
                                                          0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = 0; block_start < n; block_start = block_end) {
      block_end =
          block_start + (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end > n) {
        block_end = n;
      }

      d = libsais_partial_sorting_scan_left_to_right_32s_4k_block_omp(
          T, SA, k, buckets, d, thread_state[0].state.cache, block_start,
          block_end - block_start, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif

  return d;
}

static void libsais_partial_sorting_scan_left_to_right_32s_1k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  SA[buckets[T[n - 1]]++] =
      (n - 1) |
      (sa_sint_t)((sa_uint_t)(T[n - 2] < T[n - 1]) << (SAINT_BIT - 1));

  if (threads == 1 || n < 65536) {
    libsais_partial_sorting_scan_left_to_right_32s_1k(T, SA, buckets, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = 0; block_start < n; block_start = block_end) {
      block_end =
          block_start + (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end > n) {
        block_end = n;
      }

      libsais_partial_sorting_scan_left_to_right_32s_1k_block_omp(
          T, SA, buckets, thread_state[0].state.cache, block_start,
          block_end - block_start, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif
}

static void libsais_partial_sorting_shift_markers_8u_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, const sa_sint_t* RESTRICT buckets,
    sa_sint_t threads) {
  const fast_sint_t prefetch_distance = 64;

  const sa_sint_t* RESTRICT temp_bucket = &buckets[4 * ALPHABET_SIZE];

  fast_sint_t c;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel for schedule(static, 1) \
    num_threads(threads) if (threads > 1 && n >= 65536)
#else
  UNUSED(threads);
  UNUSED(n);
#endif
  for (c = BUCKETS_INDEX2(ALPHABET_SIZE - 1, 0); c >= BUCKETS_INDEX2(1, 0);
       c -= BUCKETS_INDEX2(1, 0)) {
    fast_sint_t i, j;
    sa_sint_t s = SAINT_MIN;
    for (i = (fast_sint_t)temp_bucket[c] - 1,
        j = (fast_sint_t)buckets[c - BUCKETS_INDEX2(1, 0)] + 3;
         i >= j; i -= 4) {
      libsais_prefetchw(&SA[i - prefetch_distance]);

      sa_sint_t p0 = SA[i - 0], q0 = (p0 & SAINT_MIN) ^ s;
      s = s ^ q0;
      SA[i - 0] = p0 ^ q0;
      sa_sint_t p1 = SA[i - 1], q1 = (p1 & SAINT_MIN) ^ s;
      s = s ^ q1;
      SA[i - 1] = p1 ^ q1;
      sa_sint_t p2 = SA[i - 2], q2 = (p2 & SAINT_MIN) ^ s;
      s = s ^ q2;
      SA[i - 2] = p2 ^ q2;
      sa_sint_t p3 = SA[i - 3], q3 = (p3 & SAINT_MIN) ^ s;
      s = s ^ q3;
      SA[i - 3] = p3 ^ q3;
    }

    for (j -= 3; i >= j; i -= 1) {
      sa_sint_t p = SA[i], q = (p & SAINT_MIN) ^ s;
      s = s ^ q;
      SA[i] = p ^ q;
    }
  }
}

static void libsais_partial_sorting_shift_markers_32s_6k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t k, const sa_sint_t* RESTRICT buckets,
    sa_sint_t threads) {
  const fast_sint_t prefetch_distance = 64;

  const sa_sint_t* RESTRICT temp_bucket = &buckets[4 * (fast_sint_t)k];

  fast_sint_t c;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel for schedule(static, 1) \
    num_threads(threads) if (threads > 1 && k >= 65536)
#else
  UNUSED(threads);
#endif
  for (c = (fast_sint_t)k - 1; c >= 1; c -= 1) {
    fast_sint_t i, j;
    sa_sint_t s = SAINT_MIN;
    for (i = (fast_sint_t)buckets[BUCKETS_INDEX4(c, 0)] - 1,
        j = (fast_sint_t)temp_bucket[BUCKETS_INDEX2(c - 1, 0)] + 3;
         i >= j; i -= 4) {
      libsais_prefetchw(&SA[i - prefetch_distance]);

      sa_sint_t p0 = SA[i - 0], q0 = (p0 & SAINT_MIN) ^ s;
      s = s ^ q0;
      SA[i - 0] = p0 ^ q0;
      sa_sint_t p1 = SA[i - 1], q1 = (p1 & SAINT_MIN) ^ s;
      s = s ^ q1;
      SA[i - 1] = p1 ^ q1;
      sa_sint_t p2 = SA[i - 2], q2 = (p2 & SAINT_MIN) ^ s;
      s = s ^ q2;
      SA[i - 2] = p2 ^ q2;
      sa_sint_t p3 = SA[i - 3], q3 = (p3 & SAINT_MIN) ^ s;
      s = s ^ q3;
      SA[i - 3] = p3 ^ q3;
    }

    for (j -= 3; i >= j; i -= 1) {
      sa_sint_t p = SA[i], q = (p & SAINT_MIN) ^ s;
      s = s ^ q;
      SA[i] = p ^ q;
    }
  }
}

static void libsais_partial_sorting_shift_markers_32s_4k(sa_sint_t* RESTRICT SA,
                                                         sa_sint_t n) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i;
  sa_sint_t s = SUFFIX_GROUP_MARKER;
  for (i = (fast_sint_t)n - 1; i >= 3; i -= 4) {
    libsais_prefetchw(&SA[i - prefetch_distance]);

    sa_sint_t p0 = SA[i - 0],
              q0 = ((p0 & SUFFIX_GROUP_MARKER) ^ s) &
                   ((sa_sint_t)(p0 > 0) << ((SUFFIX_GROUP_BIT - 1)));
    s = s ^ q0;
    SA[i - 0] = p0 ^ q0;
    sa_sint_t p1 = SA[i - 1],
              q1 = ((p1 & SUFFIX_GROUP_MARKER) ^ s) &
                   ((sa_sint_t)(p1 > 0) << ((SUFFIX_GROUP_BIT - 1)));
    s = s ^ q1;
    SA[i - 1] = p1 ^ q1;
    sa_sint_t p2 = SA[i - 2],
              q2 = ((p2 & SUFFIX_GROUP_MARKER) ^ s) &
                   ((sa_sint_t)(p2 > 0) << ((SUFFIX_GROUP_BIT - 1)));
    s = s ^ q2;
    SA[i - 2] = p2 ^ q2;
    sa_sint_t p3 = SA[i - 3],
              q3 = ((p3 & SUFFIX_GROUP_MARKER) ^ s) &
                   ((sa_sint_t)(p3 > 0) << ((SUFFIX_GROUP_BIT - 1)));
    s = s ^ q3;
    SA[i - 3] = p3 ^ q3;
  }

  for (; i >= 0; i -= 1) {
    sa_sint_t p = SA[i], q = ((p & SUFFIX_GROUP_MARKER) ^ s) &
                             ((sa_sint_t)(p > 0) << ((SUFFIX_GROUP_BIT - 1)));
    s = s ^ q;
    SA[i] = p ^ q;
  }
}

static void libsais_partial_sorting_shift_buckets_32s_6k(
    sa_sint_t k, sa_sint_t* RESTRICT buckets) {
  sa_sint_t* RESTRICT temp_bucket = &buckets[4 * (fast_sint_t)k];

  fast_sint_t i;
  for (i = BUCKETS_INDEX2(0, 0); i <= BUCKETS_INDEX2((fast_sint_t)k - 1, 0);
       i += BUCKETS_INDEX2(1, 0)) {
    buckets[2 * i + BUCKETS_INDEX4(0, 0)] =
        temp_bucket[i + BUCKETS_INDEX2(0, 0)];
    buckets[2 * i + BUCKETS_INDEX4(0, 1)] =
        temp_bucket[i + BUCKETS_INDEX2(0, 1)];
  }
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchr(&SA[i - 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - prefetch_distance - 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = SA[i - 0];
    d += (p0 < 0);
    p0 &= SAINT_MAX;
    sa_sint_t v0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] > T[p0 - 1]);
    SA[--induction_bucket[v0]] =
        (p0 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v0] != d) << (SAINT_BIT - 1));
    distinct_names[v0] = d;

    sa_sint_t p1 = SA[i - 1];
    d += (p1 < 0);
    p1 &= SAINT_MAX;
    sa_sint_t v1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] > T[p1 - 1]);
    SA[--induction_bucket[v1]] =
        (p1 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v1] != d) << (SAINT_BIT - 1));
    distinct_names[v1] = d;
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
    SA[--induction_bucket[v]] =
        (p - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v] != d) << (SAINT_BIT - 1));
    distinct_names[v] = d;
  }

  return d;
}

static sa_sint_t libsais_partial_gsa_scan_right_to_left_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchr(&SA[i - 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - prefetch_distance - 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = SA[i - 0];
    d += (p0 < 0);
    p0 &= SAINT_MAX;
    sa_sint_t v0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] > T[p0 - 1]);
    if (v0 != 1) {
      SA[--induction_bucket[v0]] =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(distinct_names[v0] != d) << (SAINT_BIT - 1));
      distinct_names[v0] = d;
    }

    sa_sint_t p1 = SA[i - 1];
    d += (p1 < 0);
    p1 &= SAINT_MAX;
    sa_sint_t v1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] > T[p1 - 1]);
    if (v1 != 1) {
      SA[--induction_bucket[v1]] =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(distinct_names[v1] != d) << (SAINT_BIT - 1));
      distinct_names[v1] = d;
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
    if (v != 1) {
      SA[--induction_bucket[v]] =
          (p - 1) |
          (sa_sint_t)((sa_uint_t)(distinct_names[v] != d) << (SAINT_BIT - 1));
      distinct_names[v] = d;
    }
  }

  return d;
}

#if defined(LIBSAIS_OPENMP)

static void libsais_partial_sorting_scan_right_to_left_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size,
    LIBSAIS_THREAD_STATE* RESTRICT state) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  memset(induction_bucket, 0, (size_t)2 * (size_t)k * sizeof(sa_sint_t));
  memset(distinct_names, 0, (size_t)2 * (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  sa_sint_t d = 1;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchr(&SA[i - 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - prefetch_distance - 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = cache[count].index = SA[i - 0];
    d += (p0 < 0);
    p0 &= SAINT_MAX;
    sa_sint_t v0 = cache[count++].symbol =
        BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] > T[p0 - 1]);
    induction_bucket[v0]++;
    distinct_names[v0] = d;
    sa_sint_t p1 = cache[count].index = SA[i - 1];
    d += (p1 < 0);
    p1 &= SAINT_MAX;
    sa_sint_t v1 = cache[count++].symbol =
        BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] > T[p1 - 1]);
    induction_bucket[v1]++;
    distinct_names[v1] = d;
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = cache[count].index = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = cache[count++].symbol =
        BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
    induction_bucket[v]++;
    distinct_names[v] = d;
  }

  state[0].state.position = (fast_sint_t)d - 1;
  state[0].state.count = count;
}

static void libsais_partial_sorting_scan_right_to_left_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT buckets,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t count, sa_sint_t d) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  fast_sint_t i, j;
  for (i = 0, j = count - 1; i < j; i += 2) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    sa_sint_t p0 = cache[i + 0].index;
    d += (p0 < 0);
    sa_sint_t v0 = cache[i + 0].symbol;
    SA[--induction_bucket[v0]] =
        (p0 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v0] != d) << (SAINT_BIT - 1));
    distinct_names[v0] = d;

    sa_sint_t p1 = cache[i + 1].index;
    d += (p1 < 0);
    sa_sint_t v1 = cache[i + 1].symbol;
    SA[--induction_bucket[v1]] =
        (p1 - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v1] != d) << (SAINT_BIT - 1));
    distinct_names[v1] = d;
  }

  for (j += 1; i < j; i += 1) {
    sa_sint_t p = cache[i].index;
    d += (p < 0);
    sa_sint_t v = cache[i].symbol;
    SA[--induction_bucket[v]] =
        (p - 1) |
        (sa_sint_t)((sa_uint_t)(distinct_names[v] != d) << (SAINT_BIT - 1));
    distinct_names[v] = d;
  }
}

static void libsais_partial_gsa_scan_right_to_left_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT buckets,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t count, sa_sint_t d) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
  sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

  fast_sint_t i, j;
  for (i = 0, j = count - 1; i < j; i += 2) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    sa_sint_t p0 = cache[i + 0].index;
    d += (p0 < 0);
    sa_sint_t v0 = cache[i + 0].symbol;
    if (v0 != 1) {
      SA[--induction_bucket[v0]] =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(distinct_names[v0] != d) << (SAINT_BIT - 1));
      distinct_names[v0] = d;
    }

    sa_sint_t p1 = cache[i + 1].index;
    d += (p1 < 0);
    sa_sint_t v1 = cache[i + 1].symbol;
    if (v1 != 1) {
      SA[--induction_bucket[v1]] =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(distinct_names[v1] != d) << (SAINT_BIT - 1));
      distinct_names[v1] = d;
    }
  }

  for (j += 1; i < j; i += 1) {
    sa_sint_t p = cache[i].index;
    d += (p < 0);
    sa_sint_t v = cache[i].symbol;
    if (v != 1) {
      SA[--induction_bucket[v]] =
          (p - 1) |
          (sa_sint_t)((sa_uint_t)(distinct_names[v] != d) << (SAINT_BIT - 1));
      distinct_names[v] = d;
    }
  }
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_sorting_scan_right_to_left_8u(
          T, SA, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_right_to_left_8u_block_prepare(
            T, SA, k, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache, omp_block_start,
            omp_block_size, &thread_state[omp_thread_num]);
      }

#pragma omp barrier

#pragma omp master
      {
        sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
        sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          sa_sint_t* RESTRICT temp_induction_bucket =
              &thread_state[t].state.buckets[0 * ALPHABET_SIZE];
          sa_sint_t* RESTRICT temp_distinct_names =
              &thread_state[t].state.buckets[2 * ALPHABET_SIZE];

          fast_sint_t c;
          for (c = 0; c < 2 * k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_induction_bucket[c];
            induction_bucket[c] = A - B;
            temp_induction_bucket[c] = A;
          }

          for (d -= 1, c = 0; c < 2 * k; c += 1) {
            sa_sint_t A = distinct_names[c], B = temp_distinct_names[c],
                      D = B + d;
            distinct_names[c] = B > 0 ? D : A;
            temp_distinct_names[c] = A;
          }
          d += 1 + (sa_sint_t)thread_state[t].state.position;
          thread_state[t].state.position =
              (fast_sint_t)d - thread_state[t].state.position;
        }
      }

#pragma omp barrier

      {
        libsais_partial_sorting_scan_right_to_left_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count,
            (sa_sint_t)thread_state[omp_thread_num].state.position);
      }
    }
#endif
  }

  return d;
}

static sa_sint_t libsais_partial_gsa_scan_right_to_left_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_gsa_scan_right_to_left_8u(
          T, SA, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_right_to_left_8u_block_prepare(
            T, SA, k, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache, omp_block_start,
            omp_block_size, &thread_state[omp_thread_num]);
      }

#pragma omp barrier

#pragma omp master
      {
        sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
        sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          sa_sint_t* RESTRICT temp_induction_bucket =
              &thread_state[t].state.buckets[0 * ALPHABET_SIZE];
          sa_sint_t* RESTRICT temp_distinct_names =
              &thread_state[t].state.buckets[2 * ALPHABET_SIZE];

          fast_sint_t c;
          for (c = 0; c < 2 * k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_induction_bucket[c];
            induction_bucket[c] = A - B;
            temp_induction_bucket[c] = A;
          }

          for (d -= 1, c = 0; c < 2 * k; c += 1) {
            sa_sint_t A = distinct_names[c], B = temp_distinct_names[c],
                      D = B + d;
            distinct_names[c] = B > 0 ? D : A;
            temp_distinct_names[c] = A;
          }
          d += 1 + (sa_sint_t)thread_state[t].state.position;
          thread_state[t].state.position =
              (fast_sint_t)d - thread_state[t].state.position;
        }
      }

#pragma omp barrier

      {
        libsais_partial_gsa_scan_right_to_left_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count,
            (sa_sint_t)thread_state[omp_thread_num].state.position);
      }
    }
#endif
  }

  return d;
}

#endif

static void libsais_partial_sorting_scan_right_to_left_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t first_lms_suffix,
    sa_sint_t left_suffixes_count, sa_sint_t d, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  fast_sint_t scan_start = (fast_sint_t)left_suffixes_count + 1;
  fast_sint_t scan_end = (fast_sint_t)n - (fast_sint_t)first_lms_suffix;

  if (threads == 1 || (scan_end - scan_start) < 65536) {
    libsais_partial_sorting_scan_right_to_left_8u(T, SA, buckets, d, scan_start,
                                                  scan_end - scan_start);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
    sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

    fast_sint_t block_start;
    for (block_start = scan_end - 1; block_start >= scan_start;) {
      if (SA[block_start] == 0) {
        block_start--;
      } else {
        fast_sint_t block_max_end =
            block_start -
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end < scan_start) {
          block_max_end = scan_start - 1;
        }
        fast_sint_t block_end = block_start - 1;
        while (block_end > block_max_end && SA[block_end] != 0) {
          block_end--;
        }
        fast_sint_t block_size = block_start - block_end;

        if (block_size < 32) {
          for (; block_start > block_end; block_start -= 1) {
            sa_sint_t p = SA[block_start];
            d += (p < 0);
            p &= SAINT_MAX;
            sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
            SA[--induction_bucket[v]] =
                (p - 1) | (sa_sint_t)((sa_uint_t)(distinct_names[v] != d)
                                      << (SAINT_BIT - 1));
            distinct_names[v] = d;
          }
        } else {
          d = libsais_partial_sorting_scan_right_to_left_8u_block_omp(
              T, SA, k, buckets, d, block_end + 1, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_partial_gsa_scan_right_to_left_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t first_lms_suffix,
    sa_sint_t left_suffixes_count, sa_sint_t d, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  fast_sint_t scan_start = (fast_sint_t)left_suffixes_count + 1;
  fast_sint_t scan_end = (fast_sint_t)n - (fast_sint_t)first_lms_suffix;

  if (threads == 1 || (scan_end - scan_start) < 65536) {
    libsais_partial_gsa_scan_right_to_left_8u(T, SA, buckets, d, scan_start,
                                              scan_end - scan_start);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    sa_sint_t* RESTRICT induction_bucket = &buckets[0 * ALPHABET_SIZE];
    sa_sint_t* RESTRICT distinct_names = &buckets[2 * ALPHABET_SIZE];

    fast_sint_t block_start;
    for (block_start = scan_end - 1; block_start >= scan_start;) {
      if (SA[block_start] == 0) {
        block_start--;
      } else {
        fast_sint_t block_max_end =
            block_start -
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end < scan_start) {
          block_max_end = scan_start - 1;
        }
        fast_sint_t block_end = block_start - 1;
        while (block_end > block_max_end && SA[block_end] != 0) {
          block_end--;
        }
        fast_sint_t block_size = block_start - block_end;

        if (block_size < 32) {
          for (; block_start > block_end; block_start -= 1) {
            sa_sint_t p = SA[block_start];
            d += (p < 0);
            p &= SAINT_MAX;
            sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
            if (v != 1) {
              SA[--induction_bucket[v]] =
                  (p - 1) | (sa_sint_t)((sa_uint_t)(distinct_names[v] != d)
                                        << (SAINT_BIT - 1));
              distinct_names[v] = d;
            }
          }
        } else {
          d = libsais_partial_gsa_scan_right_to_left_8u_block_omp(
              T, SA, k, buckets, d, block_end + 1, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_6k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + 2 * prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchr(&SA[i - 3 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i - 2 * prefetch_distance - 1] & SAINT_MAX] - 2);

    sa_sint_t p0 = SA[i - prefetch_distance - 0] & SAINT_MAX;
    sa_sint_t v0 = BUCKETS_INDEX4(T[p0 - (p0 > 0)], 0);
    libsais_prefetchw(&buckets[v0]);
    sa_sint_t p1 = SA[i - prefetch_distance - 1] & SAINT_MAX;
    sa_sint_t v1 = BUCKETS_INDEX4(T[p1 - (p1 > 0)], 0);
    libsais_prefetchw(&buckets[v1]);

    sa_sint_t p2 = SA[i - 0];
    d += (p2 < 0);
    p2 &= SAINT_MAX;
    sa_sint_t v2 = BUCKETS_INDEX4(T[p2 - 1], T[p2 - 2] > T[p2 - 1]);
    SA[--buckets[v2]] = (p2 - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v2] != d)
                                               << (SAINT_BIT - 1));
    buckets[2 + v2] = d;

    sa_sint_t p3 = SA[i - 1];
    d += (p3 < 0);
    p3 &= SAINT_MAX;
    sa_sint_t v3 = BUCKETS_INDEX4(T[p3 - 1], T[p3 - 2] > T[p3 - 1]);
    SA[--buckets[v3]] = (p3 - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v3] != d)
                                               << (SAINT_BIT - 1));
    buckets[2 + v3] = d;
  }

  for (j -= 2 * prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    d += (p < 0);
    p &= SAINT_MAX;
    sa_sint_t v = BUCKETS_INDEX4(T[p - 1], T[p - 2] > T[p - 1]);
    SA[--buckets[v]] = (p - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v] != d)
                                             << (SAINT_BIT - 1));
    buckets[2 + v] = d;
  }

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_4k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[3 * (fast_sint_t)k];
  sa_sint_t* RESTRICT distinct_names = &buckets[0 * (fast_sint_t)k];

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + 2 * prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 3 * prefetch_distance]);

    sa_sint_t s0 = SA[i - 2 * prefetch_distance - 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - 2 * prefetch_distance - 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);
    sa_sint_t s2 = SA[i - 1 * prefetch_distance - 0];
    if (s2 > 0) {
      const fast_sint_t Ts2 = T[(s2 & ~SUFFIX_GROUP_MARKER) - 1];
      libsais_prefetchw(&induction_bucket[Ts2]);
      libsais_prefetchw(&distinct_names[BUCKETS_INDEX2(Ts2, 0)]);
    }
    sa_sint_t s3 = SA[i - 1 * prefetch_distance - 1];
    if (s3 > 0) {
      const fast_sint_t Ts3 = T[(s3 & ~SUFFIX_GROUP_MARKER) - 1];
      libsais_prefetchw(&induction_bucket[Ts3]);
      libsais_prefetchw(&distinct_names[BUCKETS_INDEX2(Ts3, 0)]);
    }

    sa_sint_t p0 = SA[i - 0];
    if (p0 > 0) {
      SA[i - 0] = 0;
      d += (p0 >> (SUFFIX_GROUP_BIT - 1));
      p0 &= ~SUFFIX_GROUP_MARKER;
      sa_sint_t v0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] > T[p0 - 1]);
      SA[--induction_bucket[T[p0 - 1]]] =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p0 - 2] > T[p0 - 1]) << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v0] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v0] = d;
    }

    sa_sint_t p1 = SA[i - 1];
    if (p1 > 0) {
      SA[i - 1] = 0;
      d += (p1 >> (SUFFIX_GROUP_BIT - 1));
      p1 &= ~SUFFIX_GROUP_MARKER;
      sa_sint_t v1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] > T[p1 - 1]);
      SA[--induction_bucket[T[p1 - 1]]] =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p1 - 2] > T[p1 - 1]) << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v1] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v1] = d;
    }
  }

  for (j -= 2 * prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    if (p > 0) {
      SA[i] = 0;
      d += (p >> (SUFFIX_GROUP_BIT - 1));
      p &= ~SUFFIX_GROUP_MARKER;
      sa_sint_t v = BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
      SA[--induction_bucket[T[p - 1]]] =
          (p - 1) |
          (sa_sint_t)((sa_uint_t)(T[p - 2] > T[p - 1]) << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v] = d;
    }
  }

  return d;
}

static void libsais_partial_sorting_scan_right_to_left_32s_1k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + 2 * prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 3 * prefetch_distance]);

    sa_sint_t s0 = SA[i - 2 * prefetch_distance - 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 1];
    libsais_prefetchr(Ts0 - 1);
    sa_sint_t s1 = SA[i - 2 * prefetch_distance - 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 1];
    libsais_prefetchr(Ts1 - 1);
    sa_sint_t s2 = SA[i - 1 * prefetch_distance - 0];
    if (s2 > 0) {
      libsais_prefetchw(&induction_bucket[T[s2 - 1]]);
      libsais_prefetchr(&T[s2] - 2);
    }
    sa_sint_t s3 = SA[i - 1 * prefetch_distance - 1];
    if (s3 > 0) {
      libsais_prefetchw(&induction_bucket[T[s3 - 1]]);
      libsais_prefetchr(&T[s3] - 2);
    }

    sa_sint_t p0 = SA[i - 0];
    if (p0 > 0) {
      SA[i - 0] = 0;
      SA[--induction_bucket[T[p0 - 1]]] =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p0 - 2] > T[p0 - 1]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i - 1];
    if (p1 > 0) {
      SA[i - 1] = 0;
      SA[--induction_bucket[T[p1 - 1]]] =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p1 - 2] > T[p1 - 1]) << (SAINT_BIT - 1));
    }
  }

  for (j -= 2 * prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    if (p > 0) {
      SA[i] = 0;
      SA[--induction_bucket[T[p - 1]]] =
          (p - 1) |
          (sa_sint_t)((sa_uint_t)(T[p - 2] > T[p - 1]) << (SAINT_BIT - 1));
    }
  }
}

#if defined(LIBSAIS_OPENMP)

static void libsais_partial_sorting_scan_right_to_left_32s_6k_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 0] & SAINT_MAX] - 2);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 1);
    libsais_prefetchr(&T[SA[i + prefetch_distance + 1] & SAINT_MAX] - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t p0 = cache[i + 0].index = SA[i + 0];
    sa_sint_t symbol0 = 0;
    p0 &= SAINT_MAX;
    if (p0 != 0) {
      symbol0 = BUCKETS_INDEX4(T[p0 - 1], T[p0 - 2] > T[p0 - 1]);
    }
    cache[i + 0].symbol = symbol0;
    sa_sint_t p1 = cache[i + 1].index = SA[i + 1];
    sa_sint_t symbol1 = 0;
    p1 &= SAINT_MAX;
    if (p1 != 0) {
      symbol1 = BUCKETS_INDEX4(T[p1 - 1], T[p1 - 2] > T[p1 - 1]);
    }
    cache[i + 1].symbol = symbol1;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = cache[i].index = SA[i];
    sa_sint_t symbol = 0;
    p &= SAINT_MAX;
    if (p != 0) {
      symbol = BUCKETS_INDEX4(T[p - 1], T[p - 2] > T[p - 1]);
    }
    cache[i].symbol = symbol;
  }
}

static void libsais_partial_sorting_scan_right_to_left_32s_4k_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 & ~SUFFIX_GROUP_MARKER : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t symbol0 = SAINT_MIN, p0 = SA[i + 0];
    if (p0 > 0) {
      SA[i + 0] = 0;
      cache[i + 0].index = p0;
      p0 &= ~SUFFIX_GROUP_MARKER;
      symbol0 = BUCKETS_INDEX2(T[p0 - 1], T[p0 - 2] > T[p0 - 1]);
    }
    cache[i + 0].symbol = symbol0;
    sa_sint_t symbol1 = SAINT_MIN, p1 = SA[i + 1];
    if (p1 > 0) {
      SA[i + 1] = 0;
      cache[i + 1].index = p1;
      p1 &= ~SUFFIX_GROUP_MARKER;
      symbol1 = BUCKETS_INDEX2(T[p1 - 1], T[p1 - 2] > T[p1 - 1]);
    }
    cache[i + 1].symbol = symbol1;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t symbol = SAINT_MIN, p = SA[i];
    if (p > 0) {
      SA[i] = 0;
      cache[i].index = p;
      p &= ~SUFFIX_GROUP_MARKER;
      symbol = BUCKETS_INDEX2(T[p - 1], T[p - 2] > T[p - 1]);
    }
    cache[i].symbol = symbol;
  }
}

static void libsais_partial_sorting_scan_right_to_left_32s_1k_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t symbol0 = SAINT_MIN, p0 = SA[i + 0];
    if (p0 > 0) {
      SA[i + 0] = 0;
      cache[i + 0].index =
          (p0 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p0 - 2] > T[p0 - 1]) << (SAINT_BIT - 1));
      symbol0 = T[p0 - 1];
    }
    cache[i + 0].symbol = symbol0;
    sa_sint_t symbol1 = SAINT_MIN, p1 = SA[i + 1];
    if (p1 > 0) {
      SA[i + 1] = 0;
      cache[i + 1].index =
          (p1 - 1) |
          (sa_sint_t)((sa_uint_t)(T[p1 - 2] > T[p1 - 1]) << (SAINT_BIT - 1));
      symbol1 = T[p1 - 1];
    }
    cache[i + 1].symbol = symbol1;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t symbol = SAINT_MIN, p = SA[i];
    if (p > 0) {
      SA[i] = 0;
      cache[i].index = (p - 1) | (sa_sint_t)((sa_uint_t)(T[p - 2] > T[p - 1])
                                             << (SAINT_BIT - 1));
      symbol = T[p - 1];
    }
    cache[i].symbol = symbol;
  }
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_6k_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT buckets, sa_sint_t d,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&cache[i - 2 * prefetch_distance]);

    libsais_prefetchw(&buckets[cache[i - prefetch_distance - 0].symbol]);
    libsais_prefetchw(&buckets[cache[i - prefetch_distance - 1].symbol]);

    sa_sint_t v0 = cache[i - 0].symbol, p0 = cache[i - 0].index;
    d += (p0 < 0);
    cache[i - 0].symbol = --buckets[v0];
    cache[i - 0].index =
        (p0 - 1) |
        (sa_sint_t)((sa_uint_t)(buckets[2 + v0] != d) << (SAINT_BIT - 1));
    buckets[2 + v0] = d;
    if (cache[i - 0].symbol >= omp_block_start) {
      sa_sint_t s = cache[i - 0].symbol,
                q = (cache[s].index = cache[i - 0].index) & SAINT_MAX;
      cache[s].symbol = BUCKETS_INDEX4(T[q - 1], T[q - 2] > T[q - 1]);
    }

    sa_sint_t v1 = cache[i - 1].symbol, p1 = cache[i - 1].index;
    d += (p1 < 0);
    cache[i - 1].symbol = --buckets[v1];
    cache[i - 1].index =
        (p1 - 1) |
        (sa_sint_t)((sa_uint_t)(buckets[2 + v1] != d) << (SAINT_BIT - 1));
    buckets[2 + v1] = d;
    if (cache[i - 1].symbol >= omp_block_start) {
      sa_sint_t s = cache[i - 1].symbol,
                q = (cache[s].index = cache[i - 1].index) & SAINT_MAX;
      cache[s].symbol = BUCKETS_INDEX4(T[q - 1], T[q - 2] > T[q - 1]);
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t v = cache[i].symbol, p = cache[i].index;
    d += (p < 0);
    cache[i].symbol = --buckets[v];
    cache[i].index = (p - 1) | (sa_sint_t)((sa_uint_t)(buckets[2 + v] != d)
                                           << (SAINT_BIT - 1));
    buckets[2 + v] = d;
    if (cache[i].symbol >= omp_block_start) {
      sa_sint_t s = cache[i].symbol,
                q = (cache[s].index = cache[i].index) & SAINT_MAX;
      cache[s].symbol = BUCKETS_INDEX4(T[q - 1], T[q - 2] > T[q - 1]);
    }
  }

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_4k_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t k, sa_sint_t* RESTRICT buckets,
    sa_sint_t d, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT induction_bucket = &buckets[3 * (fast_sint_t)k];
  sa_sint_t* RESTRICT distinct_names = &buckets[0 * (fast_sint_t)k];

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&cache[i - 2 * prefetch_distance]);

    sa_sint_t s0 = cache[i - prefetch_distance - 0].symbol;
    const sa_sint_t* Is0 = &induction_bucket[s0 > 0 ? s0 >> 1 : 0];
    libsais_prefetchw(Is0);
    const sa_sint_t* Ds0 = &distinct_names[s0 > 0 ? s0 : 0];
    libsais_prefetchw(Ds0);
    sa_sint_t s1 = cache[i - prefetch_distance - 1].symbol;
    const sa_sint_t* Is1 = &induction_bucket[s1 > 0 ? s1 >> 1 : 0];
    libsais_prefetchw(Is1);
    const sa_sint_t* Ds1 = &distinct_names[s1 > 0 ? s1 : 0];
    libsais_prefetchw(Ds1);

    sa_sint_t v0 = cache[i - 0].symbol;
    if (v0 >= 0) {
      sa_sint_t p0 = cache[i - 0].index;
      d += (p0 >> (SUFFIX_GROUP_BIT - 1));
      cache[i - 0].symbol = --induction_bucket[v0 >> 1];
      cache[i - 0].index =
          (p0 - 1) | (sa_sint_t)((sa_uint_t)v0 << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v0] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v0] = d;
      if (cache[i - 0].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i - 0].symbol, np = cache[i - 0].index;
        if (np > 0) {
          cache[i - 0].index = 0;
          cache[ni].index = np;
          np &= ~SUFFIX_GROUP_MARKER;
          cache[ni].symbol = BUCKETS_INDEX2(T[np - 1], T[np - 2] > T[np - 1]);
        }
      }
    }

    sa_sint_t v1 = cache[i - 1].symbol;
    if (v1 >= 0) {
      sa_sint_t p1 = cache[i - 1].index;
      d += (p1 >> (SUFFIX_GROUP_BIT - 1));
      cache[i - 1].symbol = --induction_bucket[v1 >> 1];
      cache[i - 1].index =
          (p1 - 1) | (sa_sint_t)((sa_uint_t)v1 << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v1] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v1] = d;
      if (cache[i - 1].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i - 1].symbol, np = cache[i - 1].index;
        if (np > 0) {
          cache[i - 1].index = 0;
          cache[ni].index = np;
          np &= ~SUFFIX_GROUP_MARKER;
          cache[ni].symbol = BUCKETS_INDEX2(T[np - 1], T[np - 2] > T[np - 1]);
        }
      }
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t v = cache[i].symbol;
    if (v >= 0) {
      sa_sint_t p = cache[i].index;
      d += (p >> (SUFFIX_GROUP_BIT - 1));
      cache[i].symbol = --induction_bucket[v >> 1];
      cache[i].index =
          (p - 1) | (sa_sint_t)((sa_uint_t)v << (SAINT_BIT - 1)) |
          ((sa_sint_t)(distinct_names[v] != d) << (SUFFIX_GROUP_BIT - 1));
      distinct_names[v] = d;
      if (cache[i].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i].symbol, np = cache[i].index;
        if (np > 0) {
          cache[i].index = 0;
          cache[ni].index = np;
          np &= ~SUFFIX_GROUP_MARKER;
          cache[ni].symbol = BUCKETS_INDEX2(T[np - 1], T[np - 2] > T[np - 1]);
        }
      }
    }
  }

  return d;
}

static void libsais_partial_sorting_scan_right_to_left_32s_1k_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT induction_bucket,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&cache[i - 2 * prefetch_distance]);

    sa_sint_t s0 = cache[i - prefetch_distance - 0].symbol;
    const sa_sint_t* Is0 = &induction_bucket[s0 > 0 ? s0 : 0];
    libsais_prefetchw(Is0);
    sa_sint_t s1 = cache[i - prefetch_distance - 1].symbol;
    const sa_sint_t* Is1 = &induction_bucket[s1 > 0 ? s1 : 0];
    libsais_prefetchw(Is1);

    sa_sint_t v0 = cache[i - 0].symbol;
    if (v0 >= 0) {
      cache[i - 0].symbol = --induction_bucket[v0];
      if (cache[i - 0].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i - 0].symbol, np = cache[i - 0].index;
        if (np > 0) {
          cache[i - 0].index = 0;
          cache[ni].index =
              (np - 1) | (sa_sint_t)((sa_uint_t)(T[np - 2] > T[np - 1])
                                     << (SAINT_BIT - 1));
          cache[ni].symbol = T[np - 1];
        }
      }
    }

    sa_sint_t v1 = cache[i - 1].symbol;
    if (v1 >= 0) {
      cache[i - 1].symbol = --induction_bucket[v1];
      if (cache[i - 1].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i - 1].symbol, np = cache[i - 1].index;
        if (np > 0) {
          cache[i - 1].index = 0;
          cache[ni].index =
              (np - 1) | (sa_sint_t)((sa_uint_t)(T[np - 2] > T[np - 1])
                                     << (SAINT_BIT - 1));
          cache[ni].symbol = T[np - 1];
        }
      }
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t v = cache[i].symbol;
    if (v >= 0) {
      cache[i].symbol = --induction_bucket[v];
      if (cache[i].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i].symbol, np = cache[i].index;
        if (np > 0) {
          cache[i].index = 0;
          cache[ni].index =
              (np - 1) | (sa_sint_t)((sa_uint_t)(T[np - 2] > T[np - 1])
                                     << (SAINT_BIT - 1));
          cache[ni].symbol = T[np - 1];
        }
      }
    }
  }
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_6k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, sa_sint_t d,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_sorting_scan_right_to_left_32s_6k(
          T, SA, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_right_to_left_32s_6k_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        d = libsais_partial_sorting_scan_right_to_left_32s_6k_block_sort(
            T, buckets, d, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_place_cached_suffixes(SA, cache - block_start, omp_block_start,
                                      omp_block_size);
      }
    }
#endif
  }

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_4k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, sa_sint_t d,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      d = libsais_partial_sorting_scan_right_to_left_32s_4k(
          T, SA, k, buckets, d, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_right_to_left_32s_4k_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        d = libsais_partial_sorting_scan_right_to_left_32s_4k_block_sort(
            T, k, buckets, d, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_compact_and_place_cached_suffixes(
            SA, cache - block_start, omp_block_start, omp_block_size);
      }
    }
#endif
  }

  return d;
}

static void libsais_partial_sorting_scan_right_to_left_32s_1k_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_partial_sorting_scan_right_to_left_32s_1k(
          T, SA, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_partial_sorting_scan_right_to_left_32s_1k_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_partial_sorting_scan_right_to_left_32s_1k_block_sort(
            T, buckets, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_compact_and_place_cached_suffixes(
            SA, cache - block_start, omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

#endif

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_6k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets, sa_sint_t first_lms_suffix,
    sa_sint_t left_suffixes_count, sa_sint_t d, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  fast_sint_t scan_start = (fast_sint_t)left_suffixes_count + 1;
  fast_sint_t scan_end = (fast_sint_t)n - (fast_sint_t)first_lms_suffix;

  if (threads == 1 || (scan_end - scan_start) < 65536) {
    d = libsais_partial_sorting_scan_right_to_left_32s_6k(
        T, SA, buckets, d, scan_start, scan_end - scan_start);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = scan_end - 1; block_start >= scan_start;
         block_start = block_end) {
      block_end =
          block_start - (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end < scan_start) {
        block_end = scan_start - 1;
      }

      d = libsais_partial_sorting_scan_right_to_left_32s_6k_block_omp(
          T, SA, buckets, d, thread_state[0].state.cache, block_end + 1,
          block_start - block_end, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif

  return d;
}

static sa_sint_t libsais_partial_sorting_scan_right_to_left_32s_4k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t d, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || n < 65536) {
    d = libsais_partial_sorting_scan_right_to_left_32s_4k(T, SA, k, buckets, d,
                                                          0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = (fast_sint_t)n - 1; block_start >= 0;
         block_start = block_end) {
      block_end =
          block_start - (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end < 0) {
        block_end = -1;
      }

      d = libsais_partial_sorting_scan_right_to_left_32s_4k_block_omp(
          T, SA, k, buckets, d, thread_state[0].state.cache, block_end + 1,
          block_start - block_end, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif

  return d;
}

static void libsais_partial_sorting_scan_right_to_left_32s_1k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || n < 65536) {
    libsais_partial_sorting_scan_right_to_left_32s_1k(T, SA, buckets, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = (fast_sint_t)n - 1; block_start >= 0;
         block_start = block_end) {
      block_end =
          block_start - (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end < 0) {
        block_end = -1;
      }

      libsais_partial_sorting_scan_right_to_left_32s_1k_block_omp(
          T, SA, buckets, thread_state[0].state.cache, block_end + 1,
          block_start - block_end, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif
}

static fast_sint_t libsais_partial_sorting_gather_lms_suffixes_32s_4k(
    sa_sint_t* RESTRICT SA, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, l;
  for (i = omp_block_start, j = omp_block_start + omp_block_size - 3,
      l = omp_block_start;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + prefetch_distance]);

    sa_uint_t s0 = (sa_uint_t)SA[i + 0];
    SA[l] = (sa_sint_t)((s0 - (sa_uint_t)SUFFIX_GROUP_MARKER) &
                        (sa_uint_t)(~SUFFIX_GROUP_MARKER));
    l += ((sa_sint_t)s0 < 0);
    sa_uint_t s1 = (sa_uint_t)SA[i + 1];
    SA[l] = (sa_sint_t)((s1 - (sa_uint_t)SUFFIX_GROUP_MARKER) &
                        (sa_uint_t)(~SUFFIX_GROUP_MARKER));
    l += ((sa_sint_t)s1 < 0);
    sa_uint_t s2 = (sa_uint_t)SA[i + 2];
    SA[l] = (sa_sint_t)((s2 - (sa_uint_t)SUFFIX_GROUP_MARKER) &
                        (sa_uint_t)(~SUFFIX_GROUP_MARKER));
    l += ((sa_sint_t)s2 < 0);
    sa_uint_t s3 = (sa_uint_t)SA[i + 3];
    SA[l] = (sa_sint_t)((s3 - (sa_uint_t)SUFFIX_GROUP_MARKER) &
                        (sa_uint_t)(~SUFFIX_GROUP_MARKER));
    l += ((sa_sint_t)s3 < 0);
  }

  for (j += 3; i < j; i += 1) {
    sa_uint_t s = (sa_uint_t)SA[i];
    SA[l] = (sa_sint_t)((s - (sa_uint_t)SUFFIX_GROUP_MARKER) &
                        (sa_uint_t)(~SUFFIX_GROUP_MARKER));
    l += ((sa_sint_t)s < 0);
  }

  return l;
}

static fast_sint_t libsais_partial_sorting_gather_lms_suffixes_32s_1k(
    sa_sint_t* RESTRICT SA, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, l;
  for (i = omp_block_start, j = omp_block_start + omp_block_size - 3,
      l = omp_block_start;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + prefetch_distance]);

    sa_sint_t s0 = SA[i + 0];
    SA[l] = s0 & SAINT_MAX;
    l += (s0 < 0);
    sa_sint_t s1 = SA[i + 1];
    SA[l] = s1 & SAINT_MAX;
    l += (s1 < 0);
    sa_sint_t s2 = SA[i + 2];
    SA[l] = s2 & SAINT_MAX;
    l += (s2 < 0);
    sa_sint_t s3 = SA[i + 3];
    SA[l] = s3 & SAINT_MAX;
    l += (s3 < 0);
  }

  for (j += 3; i < j; i += 1) {
    sa_sint_t s = SA[i];
    SA[l] = s & SAINT_MAX;
    l += (s < 0);
  }

  return l;
}

static void libsais_partial_sorting_gather_lms_suffixes_32s_4k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_partial_sorting_gather_lms_suffixes_32s_4k(SA, omp_block_start,
                                                         omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.position = omp_block_start;
        thread_state[omp_thread_num].state.count =
            libsais_partial_sorting_gather_lms_suffixes_32s_4k(
                SA, omp_block_start, omp_block_size) -
            omp_block_start;
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t, position = 0;
        for (t = 0; t < omp_num_threads; ++t) {
          if (t > 0 && thread_state[t].state.count > 0) {
            memmove(&SA[position], &SA[thread_state[t].state.position],
                    (size_t)thread_state[t].state.count * sizeof(sa_sint_t));
          }

          position += thread_state[t].state.count;
        }
      }
    }
#endif
  }
}

static void libsais_partial_sorting_gather_lms_suffixes_32s_1k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_partial_sorting_gather_lms_suffixes_32s_1k(SA, omp_block_start,
                                                         omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.position = omp_block_start;
        thread_state[omp_thread_num].state.count =
            libsais_partial_sorting_gather_lms_suffixes_32s_1k(
                SA, omp_block_start, omp_block_size) -
            omp_block_start;
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t, position = 0;
        for (t = 0; t < omp_num_threads; ++t) {
          if (t > 0 && thread_state[t].state.count > 0) {
            memmove(&SA[position], &SA[thread_state[t].state.position],
                    (size_t)thread_state[t].state.count * sizeof(sa_sint_t));
          }

          position += thread_state[t].state.count;
        }
      }
    }
#endif
  }
}

static void libsais_induce_partial_order_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t flags, sa_sint_t* RESTRICT buckets, sa_sint_t first_lms_suffix,
    sa_sint_t left_suffixes_count, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  memset(&buckets[2 * ALPHABET_SIZE], 0,
         (size_t)2 * ALPHABET_SIZE * sizeof(sa_sint_t));

  if (flags & LIBSAIS_FLAGS_GSA) {
    buckets[4 * ALPHABET_SIZE + BUCKETS_INDEX2(0, 1)] =
        buckets[4 * ALPHABET_SIZE + BUCKETS_INDEX2(1, 1)] - 1;
    libsais_flip_suffix_markers_omp(
        SA, buckets[4 * ALPHABET_SIZE + BUCKETS_INDEX2(0, 1)], threads);
  }

  sa_sint_t d = libsais_partial_sorting_scan_left_to_right_8u_omp(
      T, SA, n, k, buckets, left_suffixes_count, 0, threads, thread_state);
  libsais_partial_sorting_shift_markers_8u_omp(SA, n, buckets, threads);

  if (flags & LIBSAIS_FLAGS_GSA) {
    libsais_partial_gsa_scan_right_to_left_8u_omp(
        T, SA, n, k, buckets, first_lms_suffix, left_suffixes_count, d, threads,
        thread_state);

    if (T[first_lms_suffix] == 0) {
      memmove(&SA[1], &SA[0],
              (size_t)(buckets[BUCKETS_INDEX2(1, 1)] - 1) * sizeof(sa_sint_t));
      SA[0] = first_lms_suffix | SAINT_MIN;
    }

    buckets[BUCKETS_INDEX2(0, 1)] = 0;
  } else {
    libsais_partial_sorting_scan_right_to_left_8u_omp(
        T, SA, n, k, buckets, first_lms_suffix, left_suffixes_count, d, threads,
        thread_state);
  }
}

static void libsais_induce_partial_order_32s_6k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t first_lms_suffix,
    sa_sint_t left_suffixes_count, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t d = libsais_partial_sorting_scan_left_to_right_32s_6k_omp(
      T, SA, n, buckets, left_suffixes_count, 0, threads, thread_state);
  libsais_partial_sorting_shift_markers_32s_6k_omp(SA, k, buckets, threads);
  libsais_partial_sorting_shift_buckets_32s_6k(k, buckets);
  libsais_partial_sorting_scan_right_to_left_32s_6k_omp(
      T, SA, n, buckets, first_lms_suffix, left_suffixes_count, d, threads,
      thread_state);
}

static void libsais_induce_partial_order_32s_4k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  memset(buckets, 0, 2 * (size_t)k * sizeof(sa_sint_t));

  sa_sint_t d = libsais_partial_sorting_scan_left_to_right_32s_4k_omp(
      T, SA, n, k, buckets, 0, threads, thread_state);
  libsais_partial_sorting_shift_markers_32s_4k(SA, n);
  libsais_partial_sorting_scan_right_to_left_32s_4k_omp(T, SA, n, k, buckets, d,
                                                        threads, thread_state);
  libsais_partial_sorting_gather_lms_suffixes_32s_4k_omp(SA, n, threads,
                                                         thread_state);
}

static void libsais_induce_partial_order_32s_2k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_partial_sorting_scan_left_to_right_32s_1k_omp(
      T, SA, n, &buckets[1 * (fast_sint_t)k], threads, thread_state);
  libsais_partial_sorting_scan_right_to_left_32s_1k_omp(
      T, SA, n, &buckets[0 * (fast_sint_t)k], threads, thread_state);
  libsais_partial_sorting_gather_lms_suffixes_32s_1k_omp(SA, n, threads,
                                                         thread_state);
}

static void libsais_induce_partial_order_32s_1k_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_count_suffixes_32s(T, n, k, buckets);
  libsais_initialize_buckets_start_32s_1k(k, buckets);
  libsais_partial_sorting_scan_left_to_right_32s_1k_omp(T, SA, n, buckets,
                                                        threads, thread_state);

  libsais_count_suffixes_32s(T, n, k, buckets);
  libsais_initialize_buckets_end_32s_1k(k, buckets);
  libsais_partial_sorting_scan_right_to_left_32s_1k_omp(T, SA, n, buckets,
                                                        threads, thread_state);

  libsais_partial_sorting_gather_lms_suffixes_32s_1k_omp(SA, n, threads,
                                                         thread_state);
}

static sa_sint_t libsais_renumber_lms_suffixes_8u(sa_sint_t* RESTRICT SA,
                                                  sa_sint_t m, sa_sint_t name,
                                                  fast_sint_t omp_block_start,
                                                  fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT SAm = &SA[m];

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 0] & SAINT_MAX) >> 1]);
    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 1] & SAINT_MAX) >> 1]);
    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 2] & SAINT_MAX) >> 1]);
    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 3] & SAINT_MAX) >> 1]);

    sa_sint_t p0 = SA[i + 0];
    SAm[(p0 & SAINT_MAX) >> 1] = name | SAINT_MIN;
    name += p0 < 0;
    sa_sint_t p1 = SA[i + 1];
    SAm[(p1 & SAINT_MAX) >> 1] = name | SAINT_MIN;
    name += p1 < 0;
    sa_sint_t p2 = SA[i + 2];
    SAm[(p2 & SAINT_MAX) >> 1] = name | SAINT_MIN;
    name += p2 < 0;
    sa_sint_t p3 = SA[i + 3];
    SAm[(p3 & SAINT_MAX) >> 1] = name | SAINT_MIN;
    name += p3 < 0;
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SAm[(p & SAINT_MAX) >> 1] = name | SAINT_MIN;
    name += p < 0;
  }

  return name;
}

static fast_sint_t libsais_gather_marked_lms_suffixes(
    sa_sint_t* RESTRICT SA, sa_sint_t m, fast_sint_t l,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  l -= 1;

  fast_sint_t i, j;
  for (i = (fast_sint_t)m + omp_block_start + omp_block_size - 1,
      j = (fast_sint_t)m + omp_block_start + 3;
       i >= j; i -= 4) {
    libsais_prefetchr(&SA[i - prefetch_distance]);

    sa_sint_t s0 = SA[i - 0];
    SA[l] = s0 & SAINT_MAX;
    l -= s0 < 0;
    sa_sint_t s1 = SA[i - 1];
    SA[l] = s1 & SAINT_MAX;
    l -= s1 < 0;
    sa_sint_t s2 = SA[i - 2];
    SA[l] = s2 & SAINT_MAX;
    l -= s2 < 0;
    sa_sint_t s3 = SA[i - 3];
    SA[l] = s3 & SAINT_MAX;
    l -= s3 < 0;
  }

  for (j -= 3; i >= j; i -= 1) {
    sa_sint_t s = SA[i];
    SA[l] = s & SAINT_MAX;
    l -= s < 0;
  }

  l += 1;

  return l;
}

static sa_sint_t libsais_renumber_lms_suffixes_8u_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t m, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t name = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && m >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (m / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : m - omp_block_start;

    if (omp_num_threads == 1) {
      name = libsais_renumber_lms_suffixes_8u(SA, m, 0, omp_block_start,
                                              omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_count_negative_marked_suffixes(SA, omp_block_start,
                                                   omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t t, count = 0;
        for (t = 0; t < omp_thread_num; ++t) {
          count += thread_state[t].state.count;
        }

        if (omp_thread_num == omp_num_threads - 1) {
          name = (sa_sint_t)(count + thread_state[omp_thread_num].state.count);
        }

        libsais_renumber_lms_suffixes_8u(SA, m, (sa_sint_t)count,
                                         omp_block_start, omp_block_size);
      }
    }
#endif
  }

  return name;
}

static void libsais_gather_marked_lms_suffixes_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, sa_sint_t fs,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 131072)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride =
        (((fast_sint_t)n >> 1) / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : ((fast_sint_t)n >> 1) - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_gather_marked_lms_suffixes(SA, m,
                                         (fast_sint_t)n + (fast_sint_t)fs,
                                         omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        if (omp_thread_num < omp_num_threads - 1) {
          thread_state[omp_thread_num].state.position =
              libsais_gather_marked_lms_suffixes(
                  SA, m, (fast_sint_t)m + omp_block_start + omp_block_size,
                  omp_block_start, omp_block_size);
          thread_state[omp_thread_num].state.count =
              (fast_sint_t)m + omp_block_start + omp_block_size -
              thread_state[omp_thread_num].state.position;
        } else {
          thread_state[omp_thread_num].state.position =
              libsais_gather_marked_lms_suffixes(
                  SA, m, (fast_sint_t)n + (fast_sint_t)fs, omp_block_start,
                  omp_block_size);
          thread_state[omp_thread_num].state.count =
              (fast_sint_t)n + (fast_sint_t)fs -
              thread_state[omp_thread_num].state.position;
        }
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t, position = (fast_sint_t)n + (fast_sint_t)fs;

        for (t = omp_num_threads - 1; t >= 0; --t) {
          position -= thread_state[t].state.count;
          if (t != omp_num_threads - 1 && thread_state[t].state.count > 0) {
            memmove(&SA[position], &SA[thread_state[t].state.position],
                    (size_t)thread_state[t].state.count * sizeof(sa_sint_t));
          }
        }
      }
    }
#endif
  }
}

static sa_sint_t libsais_renumber_and_gather_lms_suffixes_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, sa_sint_t fs,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  memset(&SA[m], 0, ((size_t)n >> 1) * sizeof(sa_sint_t));

  sa_sint_t name =
      libsais_renumber_lms_suffixes_8u_omp(SA, m, threads, thread_state);
  if (name < m) {
    libsais_gather_marked_lms_suffixes_omp(SA, n, m, fs, threads, thread_state);
  } else {
    fast_sint_t i;
    for (i = 0; i < m; i += 1) {
      SA[i] &= SAINT_MAX;
    }
  }

  return name;
}

static sa_sint_t libsais_renumber_distinct_lms_suffixes_32s_4k(
    sa_sint_t* RESTRICT SA, sa_sint_t m, sa_sint_t name,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT SAm = &SA[m];

  fast_sint_t i, j;
  sa_sint_t p0, p1, p2, p3 = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 0] & SAINT_MAX) >> 1]);
    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 1] & SAINT_MAX) >> 1]);
    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 2] & SAINT_MAX) >> 1]);
    libsais_prefetchw(&SAm[(SA[i + prefetch_distance + 3] & SAINT_MAX) >> 1]);

    p0 = SA[i + 0];
    SAm[(SA[i + 0] = p0 & SAINT_MAX) >> 1] = name | (p0 & p3 & SAINT_MIN);
    name += p0 < 0;
    p1 = SA[i + 1];
    SAm[(SA[i + 1] = p1 & SAINT_MAX) >> 1] = name | (p1 & p0 & SAINT_MIN);
    name += p1 < 0;
    p2 = SA[i + 2];
    SAm[(SA[i + 2] = p2 & SAINT_MAX) >> 1] = name | (p2 & p1 & SAINT_MIN);
    name += p2 < 0;
    p3 = SA[i + 3];
    SAm[(SA[i + 3] = p3 & SAINT_MAX) >> 1] = name | (p3 & p2 & SAINT_MIN);
    name += p3 < 0;
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    p2 = p3;
    p3 = SA[i];
    SAm[(SA[i] = p3 & SAINT_MAX) >> 1] = name | (p3 & p2 & SAINT_MIN);
    name += p3 < 0;
  }

  return name;
}

static void libsais_mark_distinct_lms_suffixes_32s(sa_sint_t* RESTRICT SA,
                                                   sa_sint_t m,
                                                   fast_sint_t omp_block_start,
                                                   fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  sa_sint_t p0, p1, p2, p3 = 0;
  for (i = (fast_sint_t)m + omp_block_start,
      j = (fast_sint_t)m + omp_block_start + omp_block_size - 3;
       i < j; i += 4) {
    libsais_prefetchw(&SA[i + prefetch_distance]);

    p0 = SA[i + 0];
    SA[i + 0] = p0 & (p3 | SAINT_MAX);
    p0 = (p0 == 0) ? p3 : p0;
    p1 = SA[i + 1];
    SA[i + 1] = p1 & (p0 | SAINT_MAX);
    p1 = (p1 == 0) ? p0 : p1;
    p2 = SA[i + 2];
    SA[i + 2] = p2 & (p1 | SAINT_MAX);
    p2 = (p2 == 0) ? p1 : p2;
    p3 = SA[i + 3];
    SA[i + 3] = p3 & (p2 | SAINT_MAX);
    p3 = (p3 == 0) ? p2 : p3;
  }

  for (j += 3; i < j; i += 1) {
    p2 = p3;
    p3 = SA[i];
    SA[i] = p3 & (p2 | SAINT_MAX);
    p3 = (p3 == 0) ? p2 : p3;
  }
}

static void libsais_clamp_lms_suffixes_length_32s(sa_sint_t* RESTRICT SA,
                                                  sa_sint_t m,
                                                  fast_sint_t omp_block_start,
                                                  fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT SAm = &SA[m];

  fast_sint_t i, j;
  for (i = omp_block_start, j = omp_block_start + omp_block_size - 3; i < j;
       i += 4) {
    libsais_prefetchw(&SAm[i + prefetch_distance]);

    SAm[i + 0] = (SAm[i + 0] < 0 ? SAm[i + 0] : 0) & SAINT_MAX;
    SAm[i + 1] = (SAm[i + 1] < 0 ? SAm[i + 1] : 0) & SAINT_MAX;
    SAm[i + 2] = (SAm[i + 2] < 0 ? SAm[i + 2] : 0) & SAINT_MAX;
    SAm[i + 3] = (SAm[i + 3] < 0 ? SAm[i + 3] : 0) & SAINT_MAX;
  }

  for (j += 3; i < j; i += 1) {
    SAm[i] = (SAm[i] < 0 ? SAm[i] : 0) & SAINT_MAX;
  }
}

static sa_sint_t libsais_renumber_distinct_lms_suffixes_32s_4k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t m, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t name = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && m >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (m / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : m - omp_block_start;

    if (omp_num_threads == 1) {
      name = libsais_renumber_distinct_lms_suffixes_32s_4k(
          SA, m, 1, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_count_negative_marked_suffixes(SA, omp_block_start,
                                                   omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t t, count = 1;
        for (t = 0; t < omp_thread_num; ++t) {
          count += thread_state[t].state.count;
        }

        if (omp_thread_num == omp_num_threads - 1) {
          name = (sa_sint_t)(count + thread_state[omp_thread_num].state.count);
        }

        libsais_renumber_distinct_lms_suffixes_32s_4k(
            SA, m, (sa_sint_t)count, omp_block_start, omp_block_size);
      }
    }
#endif
  }

  return name - 1;
}

static void libsais_mark_distinct_lms_suffixes_32s_omp(sa_sint_t* RESTRICT SA,
                                                       sa_sint_t n, sa_sint_t m,
                                                       sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 131072)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
    fast_sint_t omp_block_stride =
        (((fast_sint_t)n >> 1) / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : ((fast_sint_t)n >> 1) - omp_block_start;
#else
    UNUSED(threads);

    fast_sint_t omp_block_start = 0;
    fast_sint_t omp_block_size = (fast_sint_t)n >> 1;
#endif
    libsais_mark_distinct_lms_suffixes_32s(SA, m, omp_block_start,
                                           omp_block_size);
  }
}

static void libsais_clamp_lms_suffixes_length_32s_omp(sa_sint_t* RESTRICT SA,
                                                      sa_sint_t n, sa_sint_t m,
                                                      sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 131072)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
    fast_sint_t omp_block_stride =
        (((fast_sint_t)n >> 1) / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : ((fast_sint_t)n >> 1) - omp_block_start;
#else
    UNUSED(threads);

    fast_sint_t omp_block_start = 0;
    fast_sint_t omp_block_size = (fast_sint_t)n >> 1;
#endif
    libsais_clamp_lms_suffixes_length_32s(SA, m, omp_block_start,
                                          omp_block_size);
  }
}

static sa_sint_t libsais_renumber_and_mark_distinct_lms_suffixes_32s_4k_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  memset(&SA[m], 0, ((size_t)n >> 1) * sizeof(sa_sint_t));

  sa_sint_t name = libsais_renumber_distinct_lms_suffixes_32s_4k_omp(
      SA, m, threads, thread_state);
  if (name < m) {
    libsais_mark_distinct_lms_suffixes_32s_omp(SA, n, m, threads);
  }

  return name;
}

static sa_sint_t libsais_renumber_and_mark_distinct_lms_suffixes_32s_1k_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    sa_sint_t threads) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT SAm = &SA[m];

  {
    libsais_gather_lms_suffixes_32s(T, SA, n);

    memset(&SA[m], 0, ((size_t)n - (size_t)m - (size_t)m) * sizeof(sa_sint_t));

    fast_sint_t i, j;
    for (i = (fast_sint_t)n - (fast_sint_t)m,
        j = (fast_sint_t)n - 1 - prefetch_distance - 3;
         i < j; i += 4) {
      libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

      libsais_prefetchw(&SAm[((sa_uint_t)SA[i + prefetch_distance + 0]) >> 1]);
      libsais_prefetchw(&SAm[((sa_uint_t)SA[i + prefetch_distance + 1]) >> 1]);
      libsais_prefetchw(&SAm[((sa_uint_t)SA[i + prefetch_distance + 2]) >> 1]);
      libsais_prefetchw(&SAm[((sa_uint_t)SA[i + prefetch_distance + 3]) >> 1]);

      SAm[((sa_uint_t)SA[i + 0]) >> 1] = SA[i + 1] - SA[i + 0] + 1 + SAINT_MIN;
      SAm[((sa_uint_t)SA[i + 1]) >> 1] = SA[i + 2] - SA[i + 1] + 1 + SAINT_MIN;
      SAm[((sa_uint_t)SA[i + 2]) >> 1] = SA[i + 3] - SA[i + 2] + 1 + SAINT_MIN;
      SAm[((sa_uint_t)SA[i + 3]) >> 1] = SA[i + 4] - SA[i + 3] + 1 + SAINT_MIN;
    }

    for (j += prefetch_distance + 3; i < j; i += 1) {
      SAm[((sa_uint_t)SA[i]) >> 1] = SA[i + 1] - SA[i] + 1 + SAINT_MIN;
    }

    SAm[((sa_uint_t)SA[n - 1]) >> 1] = 1 + SAINT_MIN;
  }

  {
    libsais_clamp_lms_suffixes_length_32s_omp(SA, n, m, threads);
  }

  sa_sint_t name = 1;

  {
    fast_sint_t i, j, p = SA[0], plen = SAm[p >> 1];
    sa_sint_t pdiff = SAINT_MIN;
    for (i = 1, j = m - prefetch_distance - 1; i < j; i += 2) {
      libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

      libsais_prefetchw(&SAm[((sa_uint_t)SA[i + prefetch_distance + 0]) >> 1]);
      libsais_prefetchr(&T[((sa_uint_t)SA[i + prefetch_distance + 0])]);
      libsais_prefetchw(&SAm[((sa_uint_t)SA[i + prefetch_distance + 1]) >> 1]);
      libsais_prefetchr(&T[((sa_uint_t)SA[i + prefetch_distance + 1])]);

      fast_sint_t q = SA[i + 0], qlen = SAm[q >> 1];
      sa_sint_t qdiff = SAINT_MIN;
      if (plen == qlen) {
        fast_sint_t l = 0;
        do {
          if (T[p + l] != T[q + l]) {
            break;
          }
        } while (++l < qlen);
        qdiff = (sa_sint_t)(l - qlen) & SAINT_MIN;
      }
      SAm[p >> 1] = name | (pdiff & qdiff);
      name += (qdiff < 0);

      p = SA[i + 1];
      plen = SAm[p >> 1];
      pdiff = SAINT_MIN;
      if (qlen == plen) {
        fast_sint_t l = 0;
        do {
          if (T[q + l] != T[p + l]) {
            break;
          }
        } while (++l < plen);
        pdiff = (sa_sint_t)(l - plen) & SAINT_MIN;
      }
      SAm[q >> 1] = name | (qdiff & pdiff);
      name += (pdiff < 0);
    }

    for (j += prefetch_distance + 1; i < j; i += 1) {
      fast_sint_t q = SA[i], qlen = SAm[q >> 1];
      sa_sint_t qdiff = SAINT_MIN;
      if (plen == qlen) {
        fast_sint_t l = 0;
        do {
          if (T[p + l] != T[q + l]) {
            break;
          }
        } while (++l < plen);
        qdiff = (sa_sint_t)(l - plen) & SAINT_MIN;
      }
      SAm[p >> 1] = name | (pdiff & qdiff);
      name += (qdiff < 0);

      p = q;
      plen = qlen;
      pdiff = qdiff;
    }

    SAm[p >> 1] = name | pdiff;
    name++;
  }

  if (name <= m) {
    libsais_mark_distinct_lms_suffixes_32s_omp(SA, n, m, threads);
  }

  return name - 1;
}

static void libsais_reconstruct_lms_suffixes(sa_sint_t* RESTRICT SA,
                                             sa_sint_t n, sa_sint_t m,
                                             fast_sint_t omp_block_start,
                                             fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  const sa_sint_t* RESTRICT SAnm = &SA[n - m];

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&SAnm[SA[i + prefetch_distance + 0]]);
    libsais_prefetchr(&SAnm[SA[i + prefetch_distance + 1]]);
    libsais_prefetchr(&SAnm[SA[i + prefetch_distance + 2]]);
    libsais_prefetchr(&SAnm[SA[i + prefetch_distance + 3]]);

    SA[i + 0] = SAnm[SA[i + 0]];
    SA[i + 1] = SAnm[SA[i + 1]];
    SA[i + 2] = SAnm[SA[i + 2]];
    SA[i + 3] = SAnm[SA[i + 3]];
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    SA[i] = SAnm[SA[i]];
  }
}

static void libsais_reconstruct_lms_suffixes_omp(sa_sint_t* RESTRICT SA,
                                                 sa_sint_t n, sa_sint_t m,
                                                 sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && m >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
    fast_sint_t omp_block_stride = (m / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : m - omp_block_start;
#else
    UNUSED(threads);

    fast_sint_t omp_block_start = 0;
    fast_sint_t omp_block_size = m;
#endif

    libsais_reconstruct_lms_suffixes(SA, n, m, omp_block_start, omp_block_size);
  }
}

static void libsais_place_lms_suffixes_interval_8u(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, sa_sint_t flags,
    sa_sint_t* RESTRICT buckets) {
  if (flags & LIBSAIS_FLAGS_GSA) {
    buckets[7 * ALPHABET_SIZE]--;
  }

  {
    const sa_sint_t* RESTRICT bucket_end = &buckets[7 * ALPHABET_SIZE];

    fast_sint_t c, j = n;
    for (c = ALPHABET_SIZE - 2; c >= 0; --c) {
      fast_sint_t l =
          (fast_sint_t)buckets[BUCKETS_INDEX2(c, 1) + BUCKETS_INDEX2(1, 0)] -
          (fast_sint_t)buckets[BUCKETS_INDEX2(c, 1)];
      if (l > 0) {
        fast_sint_t i = bucket_end[c];
        if (j - i > 0) {
          memset(&SA[i], 0, (size_t)(j - i) * sizeof(sa_sint_t));
        }

        memmove(&SA[j = (i - l)], &SA[m -= (sa_sint_t)l],
                (size_t)l * sizeof(sa_sint_t));
      }
    }

    memset(&SA[0], 0, (size_t)j * sizeof(sa_sint_t));
  }

  if (flags & LIBSAIS_FLAGS_GSA) {
    buckets[7 * ALPHABET_SIZE]++;
  }
}

static void libsais_place_lms_suffixes_interval_32s_4k(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k, sa_sint_t m,
    const sa_sint_t* RESTRICT buckets) {
  const sa_sint_t* RESTRICT bucket_end = &buckets[3 * (fast_sint_t)k];

  fast_sint_t c, j = n;
  for (c = (fast_sint_t)k - 2; c >= 0; --c) {
    fast_sint_t l =
        (fast_sint_t)buckets[BUCKETS_INDEX2(c, 1) + BUCKETS_INDEX2(1, 0)] -
        (fast_sint_t)buckets[BUCKETS_INDEX2(c, 1)];
    if (l > 0) {
      fast_sint_t i = bucket_end[c];
      if (j - i > 0) {
        memset(&SA[i], 0, (size_t)(j - i) * sizeof(sa_sint_t));
      }

      memmove(&SA[j = (i - l)], &SA[m -= (sa_sint_t)l],
              (size_t)l * sizeof(sa_sint_t));
    }
  }

  memset(&SA[0], 0, (size_t)j * sizeof(sa_sint_t));
}

static void libsais_place_lms_suffixes_interval_32s_2k(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k, sa_sint_t m,
    const sa_sint_t* RESTRICT buckets) {
  fast_sint_t j = n;

  if (k > 1) {
    fast_sint_t c;
    for (c = BUCKETS_INDEX2((fast_sint_t)k - 2, 0); c >= BUCKETS_INDEX2(0, 0);
         c -= BUCKETS_INDEX2(1, 0)) {
      fast_sint_t l = (fast_sint_t)buckets[c + BUCKETS_INDEX2(1, 1)] -
                      (fast_sint_t)buckets[c + BUCKETS_INDEX2(0, 1)];
      if (l > 0) {
        fast_sint_t i = buckets[c];
        if (j - i > 0) {
          memset(&SA[i], 0, (size_t)(j - i) * sizeof(sa_sint_t));
        }

        memmove(&SA[j = (i - l)], &SA[m -= (sa_sint_t)l],
                (size_t)l * sizeof(sa_sint_t));
      }
    }
  }

  memset(&SA[0], 0, (size_t)j * sizeof(sa_sint_t));
}

static void libsais_place_lms_suffixes_interval_32s_1k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t m, sa_sint_t* RESTRICT buckets) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t c = k - 1;
  fast_sint_t i, l = buckets[c];
  for (i = (fast_sint_t)m - 1; i >= prefetch_distance + 3; i -= 4) {
    libsais_prefetchr(&SA[i - 2 * prefetch_distance]);

    libsais_prefetchr(&T[SA[i - prefetch_distance - 0]]);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 1]]);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 2]]);
    libsais_prefetchr(&T[SA[i - prefetch_distance - 3]]);

    sa_sint_t p0 = SA[i - 0];
    if (T[p0] != c) {
      c = T[p0];
      memset(&SA[buckets[c]], 0, (size_t)(l - buckets[c]) * sizeof(sa_sint_t));
      l = buckets[c];
    }
    SA[--l] = p0;
    sa_sint_t p1 = SA[i - 1];
    if (T[p1] != c) {
      c = T[p1];
      memset(&SA[buckets[c]], 0, (size_t)(l - buckets[c]) * sizeof(sa_sint_t));
      l = buckets[c];
    }
    SA[--l] = p1;
    sa_sint_t p2 = SA[i - 2];
    if (T[p2] != c) {
      c = T[p2];
      memset(&SA[buckets[c]], 0, (size_t)(l - buckets[c]) * sizeof(sa_sint_t));
      l = buckets[c];
    }
    SA[--l] = p2;
    sa_sint_t p3 = SA[i - 3];
    if (T[p3] != c) {
      c = T[p3];
      memset(&SA[buckets[c]], 0, (size_t)(l - buckets[c]) * sizeof(sa_sint_t));
      l = buckets[c];
    }
    SA[--l] = p3;
  }

  for (; i >= 0; i -= 1) {
    sa_sint_t p = SA[i];
    if (T[p] != c) {
      c = T[p];
      memset(&SA[buckets[c]], 0, (size_t)(l - buckets[c]) * sizeof(sa_sint_t));
      l = buckets[c];
    }
    SA[--l] = p;
  }

  memset(&SA[0], 0, (size_t)l * sizeof(sa_sint_t));
}

static void libsais_place_lms_suffixes_histogram_32s_6k(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k, sa_sint_t m,
    const sa_sint_t* RESTRICT buckets) {
  const sa_sint_t* RESTRICT bucket_end = &buckets[5 * (fast_sint_t)k];

  fast_sint_t c, j = n;
  for (c = (fast_sint_t)k - 2; c >= 0; --c) {
    fast_sint_t l = (fast_sint_t)buckets[BUCKETS_INDEX4(c, 1)];
    if (l > 0) {
      fast_sint_t i = bucket_end[c];
      if (j - i > 0) {
        memset(&SA[i], 0, (size_t)(j - i) * sizeof(sa_sint_t));
      }

      memmove(&SA[j = (i - l)], &SA[m -= (sa_sint_t)l],
              (size_t)l * sizeof(sa_sint_t));
    }
  }

  memset(&SA[0], 0, (size_t)j * sizeof(sa_sint_t));
}

static void libsais_place_lms_suffixes_histogram_32s_4k(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k, sa_sint_t m,
    const sa_sint_t* RESTRICT buckets) {
  const sa_sint_t* RESTRICT bucket_end = &buckets[3 * (fast_sint_t)k];

  fast_sint_t c, j = n;
  for (c = (fast_sint_t)k - 2; c >= 0; --c) {
    fast_sint_t l = (fast_sint_t)buckets[BUCKETS_INDEX2(c, 1)];
    if (l > 0) {
      fast_sint_t i = bucket_end[c];
      if (j - i > 0) {
        memset(&SA[i], 0, (size_t)(j - i) * sizeof(sa_sint_t));
      }

      memmove(&SA[j = (i - l)], &SA[m -= (sa_sint_t)l],
              (size_t)l * sizeof(sa_sint_t));
    }
  }

  memset(&SA[0], 0, (size_t)j * sizeof(sa_sint_t));
}

static void libsais_place_lms_suffixes_histogram_32s_2k(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k, sa_sint_t m,
    const sa_sint_t* RESTRICT buckets) {
  fast_sint_t j = n;

  if (k > 1) {
    fast_sint_t c;
    for (c = BUCKETS_INDEX2((fast_sint_t)k - 2, 0); c >= BUCKETS_INDEX2(0, 0);
         c -= BUCKETS_INDEX2(1, 0)) {
      fast_sint_t l = (fast_sint_t)buckets[c + BUCKETS_INDEX2(0, 1)];
      if (l > 0) {
        fast_sint_t i = buckets[c];
        if (j - i > 0) {
          memset(&SA[i], 0, (size_t)(j - i) * sizeof(sa_sint_t));
        }

        memmove(&SA[j = (i - l)], &SA[m -= (sa_sint_t)l],
                (size_t)l * sizeof(sa_sint_t));
      }
    }
  }

  memset(&SA[0], 0, (size_t)j * sizeof(sa_sint_t));
}

static void libsais_final_bwt_scan_left_to_right_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      SA[i + 0] = T[p0] | SAINT_MIN;
      SA[induction_bucket[T[p0]]++] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      SA[i + 1] = T[p1] | SAINT_MIN;
      SA[induction_bucket[T[p1]]++] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      SA[i] = T[p] | SAINT_MIN;
      SA[induction_bucket[T[p]]++] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p]) << (SAINT_BIT - 1));
    }
  }
}

static void libsais_final_bwt_aux_scan_left_to_right_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t rm,
    sa_sint_t* RESTRICT I, sa_sint_t* RESTRICT induction_bucket,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      SA[i + 0] = T[p0] | SAINT_MIN;
      SA[induction_bucket[T[p0]]++] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
      if ((p0 & rm) == 0) {
        I[p0 / (rm + 1)] = induction_bucket[T[p0]];
      }
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      SA[i + 1] = T[p1] | SAINT_MIN;
      SA[induction_bucket[T[p1]]++] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
      if ((p1 & rm) == 0) {
        I[p1 / (rm + 1)] = induction_bucket[T[p1]];
      }
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      SA[i] = T[p] | SAINT_MIN;
      SA[induction_bucket[T[p]]++] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p]) << (SAINT_BIT - 1));
      if ((p & rm) == 0) {
        I[p / (rm + 1)] = induction_bucket[T[p]];
      }
    }
  }
}

static void libsais_final_sorting_scan_left_to_right_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 ^ SAINT_MIN;
    if (p0 > 0) {
      p0--;
      SA[induction_bucket[T[p0]]++] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 ^ SAINT_MIN;
    if (p1 > 0) {
      p1--;
      SA[induction_bucket[T[p1]]++] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p ^ SAINT_MIN;
    if (p > 0) {
      p--;
      SA[induction_bucket[T[p]]++] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p]) << (SAINT_BIT - 1));
    }
  }
}

static void libsais_final_sorting_scan_left_to_right_32s(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - 2 * prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 3 * prefetch_distance]);

    sa_sint_t s0 = SA[i + 2 * prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 1];
    libsais_prefetchr(Ts0 - 1);
    sa_sint_t s1 = SA[i + 2 * prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 1];
    libsais_prefetchr(Ts1 - 1);
    sa_sint_t s2 = SA[i + 1 * prefetch_distance + 0];
    if (s2 > 0) {
      libsais_prefetchw(&induction_bucket[T[s2 - 1]]);
      libsais_prefetchr(&T[s2] - 2);
    }
    sa_sint_t s3 = SA[i + 1 * prefetch_distance + 1];
    if (s3 > 0) {
      libsais_prefetchw(&induction_bucket[T[s3 - 1]]);
      libsais_prefetchr(&T[s3] - 2);
    }

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 ^ SAINT_MIN;
    if (p0 > 0) {
      p0--;
      SA[induction_bucket[T[p0]]++] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 ^ SAINT_MIN;
    if (p1 > 0) {
      p1--;
      SA[induction_bucket[T[p1]]++] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j += 2 * prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p ^ SAINT_MIN;
    if (p > 0) {
      p--;
      SA[induction_bucket[T[p]]++] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p]) << (SAINT_BIT - 1));
    }
  }
}

#if defined(LIBSAIS_OPENMP)

static fast_sint_t libsais_final_bwt_scan_left_to_right_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      SA[i + 0] = T[p0] | SAINT_MIN;
      buckets[cache[count].symbol = T[p0]]++;
      cache[count++].index =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      SA[i + 1] = T[p1] | SAINT_MIN;
      buckets[cache[count].symbol = T[p1]]++;
      cache[count++].index =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      SA[i] = T[p] | SAINT_MIN;
      buckets[cache[count].symbol = T[p]]++;
      cache[count++].index = p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p])
                                             << (SAINT_BIT - 1));
    }
  }

  return count;
}

static fast_sint_t libsais_final_sorting_scan_left_to_right_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i + 0];
    SA[i + 0] = p0 ^ SAINT_MIN;
    if (p0 > 0) {
      p0--;
      buckets[cache[count].symbol = T[p0]]++;
      cache[count++].index =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i + 1];
    SA[i + 1] = p1 ^ SAINT_MIN;
    if (p1 > 0) {
      p1--;
      buckets[cache[count].symbol = T[p1]]++;
      cache[count++].index =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t p = SA[i];
    SA[i] = p ^ SAINT_MIN;
    if (p > 0) {
      p--;
      buckets[cache[count].symbol = T[p]]++;
      cache[count++].index = p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p])
                                             << (SAINT_BIT - 1));
    }
  }

  return count;
}

static void libsais_final_order_scan_left_to_right_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT buckets,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t count) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = 0, j = count - 3; i < j; i += 4) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    SA[buckets[cache[i + 0].symbol]++] = cache[i + 0].index;
    SA[buckets[cache[i + 1].symbol]++] = cache[i + 1].index;
    SA[buckets[cache[i + 2].symbol]++] = cache[i + 2].index;
    SA[buckets[cache[i + 3].symbol]++] = cache[i + 3].index;
  }

  for (j += 3; i < j; i += 1) {
    SA[buckets[cache[i].symbol]++] = cache[i].index;
  }
}

static void libsais_final_bwt_aux_scan_left_to_right_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t rm, sa_sint_t* RESTRICT I,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t count) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = 0, j = count - 3; i < j; i += 4) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    SA[buckets[cache[i + 0].symbol]++] = cache[i + 0].index;
    if ((cache[i + 0].index & rm) == 0) {
      I[(cache[i + 0].index & SAINT_MAX) / (rm + 1)] =
          buckets[cache[i + 0].symbol];
    }
    SA[buckets[cache[i + 1].symbol]++] = cache[i + 1].index;
    if ((cache[i + 1].index & rm) == 0) {
      I[(cache[i + 1].index & SAINT_MAX) / (rm + 1)] =
          buckets[cache[i + 1].symbol];
    }
    SA[buckets[cache[i + 2].symbol]++] = cache[i + 2].index;
    if ((cache[i + 2].index & rm) == 0) {
      I[(cache[i + 2].index & SAINT_MAX) / (rm + 1)] =
          buckets[cache[i + 2].symbol];
    }
    SA[buckets[cache[i + 3].symbol]++] = cache[i + 3].index;
    if ((cache[i + 3].index & rm) == 0) {
      I[(cache[i + 3].index & SAINT_MAX) / (rm + 1)] =
          buckets[cache[i + 3].symbol];
    }
  }

  for (j += 3; i < j; i += 1) {
    SA[buckets[cache[i].symbol]++] = cache[i].index;
    if ((cache[i].index & rm) == 0) {
      I[(cache[i].index & SAINT_MAX) / (rm + 1)] = buckets[cache[i].symbol];
    }
  }
}

static void libsais_final_sorting_scan_left_to_right_32s_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t symbol0 = SAINT_MIN, p0 = SA[i + 0];
    SA[i + 0] = p0 ^ SAINT_MIN;
    if (p0 > 0) {
      p0--;
      cache[i + 0].index =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] < T[p0]) << (SAINT_BIT - 1));
      symbol0 = T[p0];
    }
    cache[i + 0].symbol = symbol0;
    sa_sint_t symbol1 = SAINT_MIN, p1 = SA[i + 1];
    SA[i + 1] = p1 ^ SAINT_MIN;
    if (p1 > 0) {
      p1--;
      cache[i + 1].index =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] < T[p1]) << (SAINT_BIT - 1));
      symbol1 = T[p1];
    }
    cache[i + 1].symbol = symbol1;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t symbol = SAINT_MIN, p = SA[i];
    SA[i] = p ^ SAINT_MIN;
    if (p > 0) {
      p--;
      cache[i].index = p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p])
                                       << (SAINT_BIT - 1));
      symbol = T[p];
    }
    cache[i].symbol = symbol;
  }
}

static void libsais_final_sorting_scan_left_to_right_32s_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT induction_bucket,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, omp_block_end = omp_block_start + omp_block_size;
  for (i = omp_block_start, j = omp_block_end - prefetch_distance - 1; i < j;
       i += 2) {
    libsais_prefetchw(&cache[i + 2 * prefetch_distance]);

    sa_sint_t s0 = cache[i + prefetch_distance + 0].symbol;
    const sa_sint_t* Is0 = &induction_bucket[s0 > 0 ? s0 : 0];
    libsais_prefetchw(Is0);
    sa_sint_t s1 = cache[i + prefetch_distance + 1].symbol;
    const sa_sint_t* Is1 = &induction_bucket[s1 > 0 ? s1 : 0];
    libsais_prefetchw(Is1);

    sa_sint_t v0 = cache[i + 0].symbol;
    if (v0 >= 0) {
      cache[i + 0].symbol = induction_bucket[v0]++;
      if (cache[i + 0].symbol < omp_block_end) {
        sa_sint_t ni = cache[i + 0].symbol, np = cache[i + 0].index;
        cache[i + 0].index = np ^ SAINT_MIN;
        if (np > 0) {
          np--;
          cache[ni].index =
              np | (sa_sint_t)((sa_uint_t)(T[np - (np > 0)] < T[np])
                               << (SAINT_BIT - 1));
          cache[ni].symbol = T[np];
        }
      }
    }

    sa_sint_t v1 = cache[i + 1].symbol;
    if (v1 >= 0) {
      cache[i + 1].symbol = induction_bucket[v1]++;
      if (cache[i + 1].symbol < omp_block_end) {
        sa_sint_t ni = cache[i + 1].symbol, np = cache[i + 1].index;
        cache[i + 1].index = np ^ SAINT_MIN;
        if (np > 0) {
          np--;
          cache[ni].index =
              np | (sa_sint_t)((sa_uint_t)(T[np - (np > 0)] < T[np])
                               << (SAINT_BIT - 1));
          cache[ni].symbol = T[np];
        }
      }
    }
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t v = cache[i].symbol;
    if (v >= 0) {
      cache[i].symbol = induction_bucket[v]++;
      if (cache[i].symbol < omp_block_end) {
        sa_sint_t ni = cache[i].symbol, np = cache[i].index;
        cache[i].index = np ^ SAINT_MIN;
        if (np > 0) {
          np--;
          cache[ni].index =
              np | (sa_sint_t)((sa_uint_t)(T[np - (np > 0)] < T[np])
                               << (SAINT_BIT - 1));
          cache[ni].symbol = T[np];
        }
      }
    }
  }
}

static void libsais_final_bwt_scan_left_to_right_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_bwt_scan_left_to_right_8u(T, SA, induction_bucket,
                                              omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_bwt_scan_left_to_right_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = 0; t < omp_num_threads; ++t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A + B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_order_scan_left_to_right_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_bwt_aux_scan_left_to_right_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t rm, sa_sint_t* RESTRICT I, sa_sint_t* RESTRICT induction_bucket,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_bwt_aux_scan_left_to_right_8u(
          T, SA, rm, I, induction_bucket, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_bwt_scan_left_to_right_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = 0; t < omp_num_threads; ++t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A + B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_bwt_aux_scan_left_to_right_8u_block_place(
            SA, rm, I, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_sorting_scan_left_to_right_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_sorting_scan_left_to_right_8u(
          T, SA, induction_bucket, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_sorting_scan_left_to_right_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = 0; t < omp_num_threads; ++t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A + B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_order_scan_left_to_right_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_sorting_scan_left_to_right_32s_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_sorting_scan_left_to_right_32s(
          T, SA, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_final_sorting_scan_left_to_right_32s_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_final_sorting_scan_left_to_right_32s_block_sort(
            T, buckets, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_compact_and_place_cached_suffixes(
            SA, cache - block_start, omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

#endif

static void libsais_final_bwt_scan_left_to_right_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, fast_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  SA[induction_bucket[T[(sa_sint_t)n - 1]]++] =
      ((sa_sint_t)n - 1) |
      (sa_sint_t)((sa_uint_t)(T[(sa_sint_t)n - 2] < T[(sa_sint_t)n - 1])
                  << (SAINT_BIT - 1));

  if (threads == 1 || n < 65536) {
    libsais_final_bwt_scan_left_to_right_8u(T, SA, induction_bucket, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = 0; block_start < n;) {
      if (SA[block_start] == 0) {
        block_start++;
      } else {
        fast_sint_t block_max_end =
            block_start +
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end > n) {
          block_max_end = n;
        }
        fast_sint_t block_end = block_start + 1;
        while (block_end < block_max_end && SA[block_end] != 0) {
          block_end++;
        }
        fast_sint_t block_size = block_end - block_start;

        if (block_size < 32) {
          for (; block_start < block_end; block_start += 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p & SAINT_MAX;
            if (p > 0) {
              p--;
              SA[block_start] = T[p] | SAINT_MIN;
              SA[induction_bucket[T[p]]++] =
                  p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p])
                                  << (SAINT_BIT - 1));
            }
          }
        } else {
          libsais_final_bwt_scan_left_to_right_8u_block_omp(
              T, SA, k, induction_bucket, block_start, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_final_bwt_aux_scan_left_to_right_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, fast_sint_t n,
    sa_sint_t k, sa_sint_t rm, sa_sint_t* RESTRICT I,
    sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  SA[induction_bucket[T[(sa_sint_t)n - 1]]++] =
      ((sa_sint_t)n - 1) |
      (sa_sint_t)((sa_uint_t)(T[(sa_sint_t)n - 2] < T[(sa_sint_t)n - 1])
                  << (SAINT_BIT - 1));

  if ((((sa_sint_t)n - 1) & rm) == 0) {
    I[((sa_sint_t)n - 1) / (rm + 1)] = induction_bucket[T[(sa_sint_t)n - 1]];
  }

  if (threads == 1 || n < 65536) {
    libsais_final_bwt_aux_scan_left_to_right_8u(T, SA, rm, I, induction_bucket,
                                                0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = 0; block_start < n;) {
      if (SA[block_start] == 0) {
        block_start++;
      } else {
        fast_sint_t block_max_end =
            block_start +
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end > n) {
          block_max_end = n;
        }
        fast_sint_t block_end = block_start + 1;
        while (block_end < block_max_end && SA[block_end] != 0) {
          block_end++;
        }
        fast_sint_t block_size = block_end - block_start;

        if (block_size < 32) {
          for (; block_start < block_end; block_start += 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p & SAINT_MAX;
            if (p > 0) {
              p--;
              SA[block_start] = T[p] | SAINT_MIN;
              SA[induction_bucket[T[p]]++] =
                  p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p])
                                  << (SAINT_BIT - 1));
              if ((p & rm) == 0) {
                I[p / (rm + 1)] = induction_bucket[T[p]];
              }
            }
          }
        } else {
          libsais_final_bwt_aux_scan_left_to_right_8u_block_omp(
              T, SA, k, rm, I, induction_bucket, block_start, block_size,
              threads, thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_final_sorting_scan_left_to_right_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, fast_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  SA[induction_bucket[T[(sa_sint_t)n - 1]]++] =
      ((sa_sint_t)n - 1) |
      (sa_sint_t)((sa_uint_t)(T[(sa_sint_t)n - 2] < T[(sa_sint_t)n - 1])
                  << (SAINT_BIT - 1));

  if (threads == 1 || n < 65536) {
    libsais_final_sorting_scan_left_to_right_8u(T, SA, induction_bucket, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = 0; block_start < n;) {
      if (SA[block_start] == 0) {
        block_start++;
      } else {
        fast_sint_t block_max_end =
            block_start +
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end > n) {
          block_max_end = n;
        }
        fast_sint_t block_end = block_start + 1;
        while (block_end < block_max_end && SA[block_end] != 0) {
          block_end++;
        }
        fast_sint_t block_size = block_end - block_start;

        if (block_size < 32) {
          for (; block_start < block_end; block_start += 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p ^ SAINT_MIN;
            if (p > 0) {
              p--;
              SA[induction_bucket[T[p]]++] =
                  p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] < T[p])
                                  << (SAINT_BIT - 1));
            }
          }
        } else {
          libsais_final_sorting_scan_left_to_right_8u_block_omp(
              T, SA, k, induction_bucket, block_start, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_final_sorting_scan_left_to_right_32s_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  SA[induction_bucket[T[n - 1]]++] =
      (n - 1) |
      (sa_sint_t)((sa_uint_t)(T[n - 2] < T[n - 1]) << (SAINT_BIT - 1));

  if (threads == 1 || n < 65536) {
    libsais_final_sorting_scan_left_to_right_32s(T, SA, induction_bucket, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = 0; block_start < n; block_start = block_end) {
      block_end =
          block_start + (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end > n) {
        block_end = n;
      }

      libsais_final_sorting_scan_left_to_right_32s_block_omp(
          T, SA, induction_bucket, thread_state[0].state.cache, block_start,
          block_end - block_start, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif
}

static sa_sint_t libsais_final_bwt_scan_right_to_left_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  sa_sint_t index = -1;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    index = (p0 == 0) ? (sa_sint_t)(i - 0) : index;
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      uint8_t c0 = T[p0 - (p0 > 0)], c1 = T[p0];
      SA[i - 0] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      SA[--induction_bucket[c1]] = (c0 <= c1) ? p0 : t;
    }

    sa_sint_t p1 = SA[i - 1];
    index = (p1 == 0) ? (sa_sint_t)(i - 1) : index;
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      uint8_t c0 = T[p1 - (p1 > 0)], c1 = T[p1];
      SA[i - 1] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      SA[--induction_bucket[c1]] = (c0 <= c1) ? p1 : t;
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    index = (p == 0) ? (sa_sint_t)i : index;
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      uint8_t c0 = T[p - (p > 0)], c1 = T[p];
      SA[i] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      SA[--induction_bucket[c1]] = (c0 <= c1) ? p : t;
    }
  }

  return index;
}

static void libsais_final_bwt_aux_scan_right_to_left_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t rm,
    sa_sint_t* RESTRICT I, sa_sint_t* RESTRICT induction_bucket,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      uint8_t c0 = T[p0 - (p0 > 0)], c1 = T[p0];
      SA[i - 0] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      SA[--induction_bucket[c1]] = (c0 <= c1) ? p0 : t;
      if ((p0 & rm) == 0) {
        I[p0 / (rm + 1)] = induction_bucket[T[p0]] + 1;
      }
    }

    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      uint8_t c0 = T[p1 - (p1 > 0)], c1 = T[p1];
      SA[i - 1] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      SA[--induction_bucket[c1]] = (c0 <= c1) ? p1 : t;
      if ((p1 & rm) == 0) {
        I[p1 / (rm + 1)] = induction_bucket[T[p1]] + 1;
      }
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      uint8_t c0 = T[p - (p > 0)], c1 = T[p];
      SA[i] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      SA[--induction_bucket[c1]] = (c0 <= c1) ? p : t;
      if ((p & rm) == 0) {
        I[p / (rm + 1)] = induction_bucket[T[p]] + 1;
      }
    }
  }
}

static void libsais_final_sorting_scan_right_to_left_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      SA[--induction_bucket[T[p0]]] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] > T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      SA[--induction_bucket[T[p1]]] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] > T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      SA[--induction_bucket[T[p]]] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p]) << (SAINT_BIT - 1));
    }
  }
}

static void libsais_final_gsa_scan_right_to_left_8u(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0 && T[p0 - 1] > 0) {
      p0--;
      SA[--induction_bucket[T[p0]]] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] > T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0 && T[p1 - 1] > 0) {
      p1--;
      SA[--induction_bucket[T[p1]]] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] > T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0 && T[p - 1] > 0) {
      p--;
      SA[--induction_bucket[T[p]]] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p]) << (SAINT_BIT - 1));
    }
  }
}

static void libsais_final_sorting_scan_right_to_left_32s(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + 2 * prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 3 * prefetch_distance]);

    sa_sint_t s0 = SA[i - 2 * prefetch_distance - 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 1];
    libsais_prefetchr(Ts0 - 1);
    sa_sint_t s1 = SA[i - 2 * prefetch_distance - 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 1];
    libsais_prefetchr(Ts1 - 1);
    sa_sint_t s2 = SA[i - 1 * prefetch_distance - 0];
    if (s2 > 0) {
      libsais_prefetchw(&induction_bucket[T[s2 - 1]]);
      libsais_prefetchr(&T[s2] - 2);
    }
    sa_sint_t s3 = SA[i - 1 * prefetch_distance - 1];
    if (s3 > 0) {
      libsais_prefetchw(&induction_bucket[T[s3 - 1]]);
      libsais_prefetchr(&T[s3] - 2);
    }

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      SA[--induction_bucket[T[p0]]] =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] > T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      SA[--induction_bucket[T[p1]]] =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] > T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j -= 2 * prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      SA[--induction_bucket[T[p]]] =
          p |
          (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p]) << (SAINT_BIT - 1));
    }
  }
}

#if defined(LIBSAIS_OPENMP)

static fast_sint_t libsais_final_bwt_scan_right_to_left_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      uint8_t c0 = T[p0 - (p0 > 0)], c1 = T[p0];
      SA[i - 0] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      buckets[cache[count].symbol = c1]++;
      cache[count++].index = (c0 <= c1) ? p0 : t;
    }
    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      uint8_t c0 = T[p1 - (p1 > 0)], c1 = T[p1];
      SA[i - 1] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      buckets[cache[count].symbol = c1]++;
      cache[count++].index = (c0 <= c1) ? p1 : t;
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      uint8_t c0 = T[p - (p > 0)], c1 = T[p];
      SA[i] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      buckets[cache[count].symbol = c1]++;
      cache[count++].index = (c0 <= c1) ? p : t;
    }
  }

  return count;
}

static fast_sint_t libsais_final_bwt_aux_scan_right_to_left_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      uint8_t c0 = T[p0 - (p0 > 0)], c1 = T[p0];
      SA[i - 0] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      buckets[cache[count].symbol = c1]++;
      cache[count].index = (c0 <= c1) ? p0 : t;
      cache[count + 1].index = p0;
      count += 2;
    }
    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      uint8_t c0 = T[p1 - (p1 > 0)], c1 = T[p1];
      SA[i - 1] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      buckets[cache[count].symbol = c1]++;
      cache[count].index = (c0 <= c1) ? p1 : t;
      cache[count + 1].index = p1;
      count += 2;
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      uint8_t c0 = T[p - (p > 0)], c1 = T[p];
      SA[i] = c1;
      sa_sint_t t = c0 | SAINT_MIN;
      buckets[cache[count].symbol = c1]++;
      cache[count].index = (c0 <= c1) ? p : t;
      cache[count + 1].index = p;
      count += 2;
    }
  }

  return count;
}

static fast_sint_t libsais_final_sorting_scan_right_to_left_8u_block_prepare(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  memset(buckets, 0, (size_t)k * sizeof(sa_sint_t));

  fast_sint_t i, j, count = 0;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&SA[i - 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i - prefetch_distance - 0];
    const uint8_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i - prefetch_distance - 1];
    const uint8_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    sa_sint_t p0 = SA[i - 0];
    SA[i - 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      buckets[cache[count].symbol = T[p0]]++;
      cache[count++].index =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] > T[p0]) << (SAINT_BIT - 1));
    }
    sa_sint_t p1 = SA[i - 1];
    SA[i - 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      buckets[cache[count].symbol = T[p1]]++;
      cache[count++].index =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] > T[p1]) << (SAINT_BIT - 1));
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      buckets[cache[count].symbol = T[p]]++;
      cache[count++].index = p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p])
                                             << (SAINT_BIT - 1));
    }
  }

  return count;
}

static void libsais_final_order_scan_right_to_left_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT buckets,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t count) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = 0, j = count - 3; i < j; i += 4) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    SA[--buckets[cache[i + 0].symbol]] = cache[i + 0].index;
    SA[--buckets[cache[i + 1].symbol]] = cache[i + 1].index;
    SA[--buckets[cache[i + 2].symbol]] = cache[i + 2].index;
    SA[--buckets[cache[i + 3].symbol]] = cache[i + 3].index;
  }

  for (j += 3; i < j; i += 1) {
    SA[--buckets[cache[i].symbol]] = cache[i].index;
  }
}

static void libsais_final_gsa_scan_right_to_left_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t* RESTRICT buckets,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t count) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = 0, j = count - 3; i < j; i += 4) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    if (cache[i + 0].symbol > 0) {
      SA[--buckets[cache[i + 0].symbol]] = cache[i + 0].index;
    }
    if (cache[i + 1].symbol > 0) {
      SA[--buckets[cache[i + 1].symbol]] = cache[i + 1].index;
    }
    if (cache[i + 2].symbol > 0) {
      SA[--buckets[cache[i + 2].symbol]] = cache[i + 2].index;
    }
    if (cache[i + 3].symbol > 0) {
      SA[--buckets[cache[i + 3].symbol]] = cache[i + 3].index;
    }
  }

  for (j += 3; i < j; i += 1) {
    if (cache[i].symbol > 0) {
      SA[--buckets[cache[i].symbol]] = cache[i].index;
    }
  }
}

static void libsais_final_bwt_aux_scan_right_to_left_8u_block_place(
    sa_sint_t* RESTRICT SA, sa_sint_t rm, sa_sint_t* RESTRICT I,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t count) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = 0, j = count - 6; i < j; i += 8) {
    libsais_prefetchr(&cache[i + prefetch_distance]);

    SA[--buckets[cache[i + 0].symbol]] = cache[i + 0].index;
    if ((cache[i + 1].index & rm) == 0) {
      I[cache[i + 1].index / (rm + 1)] = buckets[cache[i + 0].symbol] + 1;
    }
    SA[--buckets[cache[i + 2].symbol]] = cache[i + 2].index;
    if ((cache[i + 3].index & rm) == 0) {
      I[cache[i + 3].index / (rm + 1)] = buckets[cache[i + 2].symbol] + 1;
    }
    SA[--buckets[cache[i + 4].symbol]] = cache[i + 4].index;
    if ((cache[i + 5].index & rm) == 0) {
      I[cache[i + 5].index / (rm + 1)] = buckets[cache[i + 4].symbol] + 1;
    }
    SA[--buckets[cache[i + 6].symbol]] = cache[i + 6].index;
    if ((cache[i + 7].index & rm) == 0) {
      I[cache[i + 7].index / (rm + 1)] = buckets[cache[i + 6].symbol] + 1;
    }
  }

  for (j += 6; i < j; i += 2) {
    SA[--buckets[cache[i].symbol]] = cache[i].index;
    if ((cache[i + 1].index & rm) == 0) {
      I[(cache[i + 1].index & SAINT_MAX) / (rm + 1)] =
          buckets[cache[i].symbol] + 1;
    }
  }
}

static void libsais_final_sorting_scan_right_to_left_32s_block_gather(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 1;
       i < j; i += 2) {
    libsais_prefetchw(&SA[i + 2 * prefetch_distance]);

    sa_sint_t s0 = SA[i + prefetch_distance + 0];
    const sa_sint_t* Ts0 = &T[s0 > 0 ? s0 : 2];
    libsais_prefetchr(Ts0 - 1);
    libsais_prefetchr(Ts0 - 2);
    sa_sint_t s1 = SA[i + prefetch_distance + 1];
    const sa_sint_t* Ts1 = &T[s1 > 0 ? s1 : 2];
    libsais_prefetchr(Ts1 - 1);
    libsais_prefetchr(Ts1 - 2);

    libsais_prefetchw(&cache[i + prefetch_distance]);

    sa_sint_t symbol0 = SAINT_MIN, p0 = SA[i + 0];
    SA[i + 0] = p0 & SAINT_MAX;
    if (p0 > 0) {
      p0--;
      cache[i + 0].index =
          p0 |
          (sa_sint_t)((sa_uint_t)(T[p0 - (p0 > 0)] > T[p0]) << (SAINT_BIT - 1));
      symbol0 = T[p0];
    }
    cache[i + 0].symbol = symbol0;
    sa_sint_t symbol1 = SAINT_MIN, p1 = SA[i + 1];
    SA[i + 1] = p1 & SAINT_MAX;
    if (p1 > 0) {
      p1--;
      cache[i + 1].index =
          p1 |
          (sa_sint_t)((sa_uint_t)(T[p1 - (p1 > 0)] > T[p1]) << (SAINT_BIT - 1));
      symbol1 = T[p1];
    }
    cache[i + 1].symbol = symbol1;
  }

  for (j += prefetch_distance + 1; i < j; i += 1) {
    sa_sint_t symbol = SAINT_MIN, p = SA[i];
    SA[i] = p & SAINT_MAX;
    if (p > 0) {
      p--;
      cache[i].index = p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p])
                                       << (SAINT_BIT - 1));
      symbol = T[p];
    }
    cache[i].symbol = symbol;
  }
}

static void libsais_final_sorting_scan_right_to_left_32s_block_sort(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT induction_bucket,
    LIBSAIS_THREAD_CACHE* RESTRICT cache, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start + omp_block_size - 1,
      j = omp_block_start + prefetch_distance + 1;
       i >= j; i -= 2) {
    libsais_prefetchw(&cache[i - 2 * prefetch_distance]);

    sa_sint_t s0 = cache[i - prefetch_distance - 0].symbol;
    const sa_sint_t* Is0 = &induction_bucket[s0 > 0 ? s0 : 0];
    libsais_prefetchw(Is0);
    sa_sint_t s1 = cache[i - prefetch_distance - 1].symbol;
    const sa_sint_t* Is1 = &induction_bucket[s1 > 0 ? s1 : 0];
    libsais_prefetchw(Is1);

    sa_sint_t v0 = cache[i - 0].symbol;
    if (v0 >= 0) {
      cache[i - 0].symbol = --induction_bucket[v0];
      if (cache[i - 0].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i - 0].symbol, np = cache[i - 0].index;
        cache[i - 0].index = np & SAINT_MAX;
        if (np > 0) {
          np--;
          cache[ni].index =
              np | (sa_sint_t)((sa_uint_t)(T[np - (np > 0)] > T[np])
                               << (SAINT_BIT - 1));
          cache[ni].symbol = T[np];
        }
      }
    }

    sa_sint_t v1 = cache[i - 1].symbol;
    if (v1 >= 0) {
      cache[i - 1].symbol = --induction_bucket[v1];
      if (cache[i - 1].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i - 1].symbol, np = cache[i - 1].index;
        cache[i - 1].index = np & SAINT_MAX;
        if (np > 0) {
          np--;
          cache[ni].index =
              np | (sa_sint_t)((sa_uint_t)(T[np - (np > 0)] > T[np])
                               << (SAINT_BIT - 1));
          cache[ni].symbol = T[np];
        }
      }
    }
  }

  for (j -= prefetch_distance + 1; i >= j; i -= 1) {
    sa_sint_t v = cache[i].symbol;
    if (v >= 0) {
      cache[i].symbol = --induction_bucket[v];
      if (cache[i].symbol >= omp_block_start) {
        sa_sint_t ni = cache[i].symbol, np = cache[i].index;
        cache[i].index = np & SAINT_MAX;
        if (np > 0) {
          np--;
          cache[ni].index =
              np | (sa_sint_t)((sa_uint_t)(T[np - (np > 0)] > T[np])
                               << (SAINT_BIT - 1));
          cache[ni].symbol = T[np];
        }
      }
    }
  }
}

static void libsais_final_bwt_scan_right_to_left_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_bwt_scan_right_to_left_8u(T, SA, induction_bucket,
                                              omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_bwt_scan_right_to_left_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A - B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_order_scan_right_to_left_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_bwt_aux_scan_right_to_left_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t rm, sa_sint_t* RESTRICT I, sa_sint_t* RESTRICT induction_bucket,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_bwt_aux_scan_right_to_left_8u(
          T, SA, rm, I, induction_bucket, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_bwt_aux_scan_right_to_left_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A - B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_bwt_aux_scan_right_to_left_8u_block_place(
            SA, rm, I, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_sorting_scan_right_to_left_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_sorting_scan_right_to_left_8u(
          T, SA, induction_bucket, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_sorting_scan_right_to_left_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A - B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_order_scan_right_to_left_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_gsa_scan_right_to_left_8u_block_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, fast_sint_t block_start,
    fast_sint_t block_size, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(                                             \
        threads) if (threads > 1 && block_size >= 64 * (k > 256 ? k : 256) && \
                         omp_get_dynamic() == 0)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(k);
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_gsa_scan_right_to_left_8u(T, SA, induction_bucket,
                                              omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_final_sorting_scan_right_to_left_8u_block_prepare(
                T, SA, k, thread_state[omp_thread_num].state.buckets,
                thread_state[omp_thread_num].state.cache, omp_block_start,
                omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t;
        for (t = omp_num_threads - 1; t >= 0; --t) {
          sa_sint_t* RESTRICT temp_bucket = thread_state[t].state.buckets;
          fast_sint_t c;
          for (c = 0; c < k; c += 1) {
            sa_sint_t A = induction_bucket[c], B = temp_bucket[c];
            induction_bucket[c] = A - B;
            temp_bucket[c] = A;
          }
        }
      }

#pragma omp barrier

      {
        libsais_final_gsa_scan_right_to_left_8u_block_place(
            SA, thread_state[omp_thread_num].state.buckets,
            thread_state[omp_thread_num].state.cache,
            thread_state[omp_thread_num].state.count);
      }
    }
#endif
  }
}

static void libsais_final_sorting_scan_right_to_left_32s_block_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    sa_sint_t* RESTRICT buckets, LIBSAIS_THREAD_CACHE* RESTRICT cache,
    fast_sint_t block_start, fast_sint_t block_size, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && \
                                                  block_size >= 16384)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(cache);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (block_size / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : block_size - omp_block_start;

    omp_block_start += block_start;

    if (omp_num_threads == 1) {
      libsais_final_sorting_scan_right_to_left_32s(
          T, SA, buckets, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        libsais_final_sorting_scan_right_to_left_32s_block_gather(
            T, SA, cache - block_start, omp_block_start, omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_final_sorting_scan_right_to_left_32s_block_sort(
            T, buckets, cache - block_start, block_start, block_size);
      }

#pragma omp barrier

      {
        libsais_compact_and_place_cached_suffixes(
            SA, cache - block_start, omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

#endif

static sa_sint_t libsais_final_bwt_scan_right_to_left_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t index = -1;

  if (threads == 1 || n < 65536) {
    index =
        libsais_final_bwt_scan_right_to_left_8u(T, SA, induction_bucket, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = (fast_sint_t)n - 1; block_start >= 0;) {
      if (SA[block_start] == 0) {
        index = (sa_sint_t)block_start--;
      } else {
        fast_sint_t block_max_end =
            block_start -
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end < 0) {
          block_max_end = -1;
        }
        fast_sint_t block_end = block_start - 1;
        while (block_end > block_max_end && SA[block_end] != 0) {
          block_end--;
        }
        fast_sint_t block_size = block_start - block_end;

        if (block_size < 32) {
          for (; block_start > block_end; block_start -= 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p & SAINT_MAX;
            if (p > 0) {
              p--;
              uint8_t c0 = T[p - (p > 0)], c1 = T[p];
              SA[block_start] = c1;
              sa_sint_t t = c0 | SAINT_MIN;
              SA[--induction_bucket[c1]] = (c0 <= c1) ? p : t;
            }
          }
        } else {
          libsais_final_bwt_scan_right_to_left_8u_block_omp(
              T, SA, k, induction_bucket, block_end + 1, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif

  return index;
}

static void libsais_final_bwt_aux_scan_right_to_left_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t rm, sa_sint_t* RESTRICT I, sa_sint_t* RESTRICT induction_bucket,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || n < 65536) {
    libsais_final_bwt_aux_scan_right_to_left_8u(T, SA, rm, I, induction_bucket,
                                                0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = (fast_sint_t)n - 1; block_start >= 0;) {
      if (SA[block_start] == 0) {
        block_start--;
      } else {
        fast_sint_t block_max_end =
            block_start -
            ((fast_sint_t)threads) *
                ((LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads) /
                 2);
        if (block_max_end < 0) {
          block_max_end = -1;
        }
        fast_sint_t block_end = block_start - 1;
        while (block_end > block_max_end && SA[block_end] != 0) {
          block_end--;
        }
        fast_sint_t block_size = block_start - block_end;

        if (block_size < 32) {
          for (; block_start > block_end; block_start -= 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p & SAINT_MAX;
            if (p > 0) {
              p--;
              uint8_t c0 = T[p - (p > 0)], c1 = T[p];
              SA[block_start] = c1;
              sa_sint_t t = c0 | SAINT_MIN;
              SA[--induction_bucket[c1]] = (c0 <= c1) ? p : t;
              if ((p & rm) == 0) {
                I[p / (rm + 1)] = induction_bucket[T[p]] + 1;
              }
            }
          }
        } else {
          libsais_final_bwt_aux_scan_right_to_left_8u_block_omp(
              T, SA, k, rm, I, induction_bucket, block_end + 1, block_size,
              threads, thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_final_sorting_scan_right_to_left_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || omp_block_size < 65536) {
    libsais_final_sorting_scan_right_to_left_8u(
        T, SA, induction_bucket, omp_block_start, omp_block_size);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = omp_block_start + omp_block_size - 1;
         block_start >= omp_block_start;) {
      if (SA[block_start] == 0) {
        block_start--;
      } else {
        fast_sint_t block_max_end =
            block_start -
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end < omp_block_start) {
          block_max_end = omp_block_start - 1;
        }
        fast_sint_t block_end = block_start - 1;
        while (block_end > block_max_end && SA[block_end] != 0) {
          block_end--;
        }
        fast_sint_t block_size = block_start - block_end;

        if (block_size < 32) {
          for (; block_start > block_end; block_start -= 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p & SAINT_MAX;
            if (p > 0) {
              p--;
              SA[--induction_bucket[T[p]]] =
                  p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p])
                                  << (SAINT_BIT - 1));
            }
          }
        } else {
          libsais_final_sorting_scan_right_to_left_8u_block_omp(
              T, SA, k, induction_bucket, block_end + 1, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_final_gsa_scan_right_to_left_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size, sa_sint_t k,
    sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || omp_block_size < 65536) {
    libsais_final_gsa_scan_right_to_left_8u(T, SA, induction_bucket,
                                            omp_block_start, omp_block_size);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start;
    for (block_start = omp_block_start + omp_block_size - 1;
         block_start >= omp_block_start;) {
      if (SA[block_start] == 0) {
        block_start--;
      } else {
        fast_sint_t block_max_end =
            block_start -
            ((fast_sint_t)threads) *
                (LIBSAIS_PER_THREAD_CACHE_SIZE - 16 * (fast_sint_t)threads);
        if (block_max_end < omp_block_start) {
          block_max_end = omp_block_start - 1;
        }
        fast_sint_t block_end = block_start - 1;
        while (block_end > block_max_end && SA[block_end] != 0) {
          block_end--;
        }
        fast_sint_t block_size = block_start - block_end;

        if (block_size < 32) {
          for (; block_start > block_end; block_start -= 1) {
            sa_sint_t p = SA[block_start];
            SA[block_start] = p & SAINT_MAX;
            if (p > 0 && T[p - 1] > 0) {
              p--;
              SA[--induction_bucket[T[p]]] =
                  p | (sa_sint_t)((sa_uint_t)(T[p - (p > 0)] > T[p])
                                  << (SAINT_BIT - 1));
            }
          }
        } else {
          libsais_final_gsa_scan_right_to_left_8u_block_omp(
              T, SA, k, induction_bucket, block_end + 1, block_size, threads,
              thread_state);
          block_start = block_end;
        }
      }
    }
  }
#else
  UNUSED(k);
  UNUSED(thread_state);
#endif
}

static void libsais_final_sorting_scan_right_to_left_32s_omp(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t* RESTRICT induction_bucket, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (threads == 1 || n < 65536) {
    libsais_final_sorting_scan_right_to_left_32s(T, SA, induction_bucket, 0, n);
  }
#if defined(LIBSAIS_OPENMP)
  else {
    fast_sint_t block_start, block_end;
    for (block_start = (fast_sint_t)n - 1; block_start >= 0;
         block_start = block_end) {
      block_end =
          block_start - (fast_sint_t)threads * LIBSAIS_PER_THREAD_CACHE_SIZE;
      if (block_end < 0) {
        block_end = -1;
      }

      libsais_final_sorting_scan_right_to_left_32s_block_omp(
          T, SA, induction_bucket, thread_state[0].state.cache, block_end + 1,
          block_start - block_end, threads);
    }
  }
#else
  UNUSED(thread_state);
#endif
}

static void libsais_clear_lms_suffixes_omp(sa_sint_t* RESTRICT SA, sa_sint_t n,
                                           sa_sint_t k,
                                           sa_sint_t* RESTRICT bucket_start,
                                           sa_sint_t* RESTRICT bucket_end,
                                           sa_sint_t threads) {
  fast_sint_t c;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel for schedule(static, 1) \
    num_threads(threads) if (threads > 1 && n >= 65536)
#else
  UNUSED(threads);
  UNUSED(n);
#endif
  for (c = 0; c < k; ++c) {
    if (bucket_end[c] > bucket_start[c]) {
      memset(&SA[bucket_start[c]], 0,
             ((size_t)bucket_end[c] - (size_t)bucket_start[c]) *
                 sizeof(sa_sint_t));
    }
  }
}

static sa_sint_t libsais_induce_final_order_8u_omp(
    const uint8_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t flags, sa_sint_t r, sa_sint_t* RESTRICT I,
    sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if ((flags & LIBSAIS_FLAGS_BWT) == 0) {
    if (flags & LIBSAIS_FLAGS_GSA) {
      buckets[6 * ALPHABET_SIZE] = buckets[7 * ALPHABET_SIZE] - 1;
    }

    libsais_final_sorting_scan_left_to_right_8u_omp(
        T, SA, n, k, &buckets[6 * ALPHABET_SIZE], threads, thread_state);
    if (threads > 1 && n >= 65536) {
      libsais_clear_lms_suffixes_omp(SA, n, ALPHABET_SIZE,
                                     &buckets[6 * ALPHABET_SIZE],
                                     &buckets[7 * ALPHABET_SIZE], threads);
    }

    if (flags & LIBSAIS_FLAGS_GSA) {
      libsais_flip_suffix_markers_omp(SA, buckets[7 * ALPHABET_SIZE], threads);
      libsais_final_gsa_scan_right_to_left_8u_omp(
          T, SA, buckets[7 * ALPHABET_SIZE],
          (fast_sint_t)n - buckets[7 * ALPHABET_SIZE], k,
          &buckets[7 * ALPHABET_SIZE], threads, thread_state);
    } else {
      libsais_final_sorting_scan_right_to_left_8u_omp(
          T, SA, 0, n, k, &buckets[7 * ALPHABET_SIZE], threads, thread_state);
    }

    return 0;
  } else if (I != NULL) {
    libsais_final_bwt_aux_scan_left_to_right_8u_omp(T, SA, n, k, r - 1, I,
                                                    &buckets[6 * ALPHABET_SIZE],
                                                    threads, thread_state);
    if (threads > 1 && n >= 65536) {
      libsais_clear_lms_suffixes_omp(SA, n, ALPHABET_SIZE,
                                     &buckets[6 * ALPHABET_SIZE],
                                     &buckets[7 * ALPHABET_SIZE], threads);
    }
    libsais_final_bwt_aux_scan_right_to_left_8u_omp(T, SA, n, k, r - 1, I,
                                                    &buckets[7 * ALPHABET_SIZE],
                                                    threads, thread_state);
    return 0;
  } else {
    libsais_final_bwt_scan_left_to_right_8u_omp(
        T, SA, n, k, &buckets[6 * ALPHABET_SIZE], threads, thread_state);
    if (threads > 1 && n >= 65536) {
      libsais_clear_lms_suffixes_omp(SA, n, ALPHABET_SIZE,
                                     &buckets[6 * ALPHABET_SIZE],
                                     &buckets[7 * ALPHABET_SIZE], threads);
    }
    return libsais_final_bwt_scan_right_to_left_8u_omp(
        T, SA, n, k, &buckets[7 * ALPHABET_SIZE], threads, thread_state);
  }
}

static void libsais_induce_final_order_32s_6k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_final_sorting_scan_left_to_right_32s_omp(
      T, SA, n, &buckets[4 * (fast_sint_t)k], threads, thread_state);
  libsais_final_sorting_scan_right_to_left_32s_omp(
      T, SA, n, &buckets[5 * (fast_sint_t)k], threads, thread_state);
}

static void libsais_induce_final_order_32s_4k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_final_sorting_scan_left_to_right_32s_omp(
      T, SA, n, &buckets[2 * (fast_sint_t)k], threads, thread_state);
  libsais_final_sorting_scan_right_to_left_32s_omp(
      T, SA, n, &buckets[3 * (fast_sint_t)k], threads, thread_state);
}

static void libsais_induce_final_order_32s_2k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_final_sorting_scan_left_to_right_32s_omp(
      T, SA, n, &buckets[1 * (fast_sint_t)k], threads, thread_state);
  libsais_final_sorting_scan_right_to_left_32s_omp(
      T, SA, n, &buckets[0 * (fast_sint_t)k], threads, thread_state);
}

static void libsais_induce_final_order_32s_1k(
    const sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n,
    sa_sint_t k, sa_sint_t* RESTRICT buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_count_suffixes_32s(T, n, k, buckets);
  libsais_initialize_buckets_start_32s_1k(k, buckets);
  libsais_final_sorting_scan_left_to_right_32s_omp(T, SA, n, buckets, threads,
                                                   thread_state);

  libsais_count_suffixes_32s(T, n, k, buckets);
  libsais_initialize_buckets_end_32s_1k(k, buckets);
  libsais_final_sorting_scan_right_to_left_32s_omp(T, SA, n, buckets, threads,
                                                   thread_state);
}

static sa_sint_t libsais_renumber_unique_and_nonunique_lms_suffixes_32s(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t m, sa_sint_t f,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT SAm = &SA[m];

  sa_sint_t i, j;
  for (i = (sa_sint_t)omp_block_start, j = (sa_sint_t)omp_block_start +
                                           (sa_sint_t)omp_block_size -
                                           2 * (sa_sint_t)prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + 3 * prefetch_distance]);

    libsais_prefetchw(
        &SAm[((sa_uint_t)SA[i + 2 * prefetch_distance + 0]) >> 1]);
    libsais_prefetchw(
        &SAm[((sa_uint_t)SA[i + 2 * prefetch_distance + 1]) >> 1]);
    libsais_prefetchw(
        &SAm[((sa_uint_t)SA[i + 2 * prefetch_distance + 2]) >> 1]);
    libsais_prefetchw(
        &SAm[((sa_uint_t)SA[i + 2 * prefetch_distance + 3]) >> 1]);

    sa_uint_t q0 = (sa_uint_t)SA[i + prefetch_distance + 0];
    sa_sint_t* RESTRICT Tq0 = &T[q0];
    libsais_prefetchw(SAm[q0 >> 1] < 0 ? Tq0 : &SAm[q0 >> 1]);
    sa_uint_t q1 = (sa_uint_t)SA[i + prefetch_distance + 1];
    sa_sint_t* RESTRICT Tq1 = &T[q1];
    libsais_prefetchw(SAm[q1 >> 1] < 0 ? Tq1 : &SAm[q1 >> 1]);
    sa_uint_t q2 = (sa_uint_t)SA[i + prefetch_distance + 2];
    sa_sint_t* RESTRICT Tq2 = &T[q2];
    libsais_prefetchw(SAm[q2 >> 1] < 0 ? Tq2 : &SAm[q2 >> 1]);
    sa_uint_t q3 = (sa_uint_t)SA[i + prefetch_distance + 3];
    sa_sint_t* RESTRICT Tq3 = &T[q3];
    libsais_prefetchw(SAm[q3 >> 1] < 0 ? Tq3 : &SAm[q3 >> 1]);

    sa_uint_t p0 = (sa_uint_t)SA[i + 0];
    sa_sint_t s0 = SAm[p0 >> 1];
    if (s0 < 0) {
      T[p0] |= SAINT_MIN;
      f++;
      s0 = i + 0 + SAINT_MIN + f;
    }
    SAm[p0 >> 1] = s0 - f;
    sa_uint_t p1 = (sa_uint_t)SA[i + 1];
    sa_sint_t s1 = SAm[p1 >> 1];
    if (s1 < 0) {
      T[p1] |= SAINT_MIN;
      f++;
      s1 = i + 1 + SAINT_MIN + f;
    }
    SAm[p1 >> 1] = s1 - f;
    sa_uint_t p2 = (sa_uint_t)SA[i + 2];
    sa_sint_t s2 = SAm[p2 >> 1];
    if (s2 < 0) {
      T[p2] |= SAINT_MIN;
      f++;
      s2 = i + 2 + SAINT_MIN + f;
    }
    SAm[p2 >> 1] = s2 - f;
    sa_uint_t p3 = (sa_uint_t)SA[i + 3];
    sa_sint_t s3 = SAm[p3 >> 1];
    if (s3 < 0) {
      T[p3] |= SAINT_MIN;
      f++;
      s3 = i + 3 + SAINT_MIN + f;
    }
    SAm[p3 >> 1] = s3 - f;
  }

  for (j += 2 * (sa_sint_t)prefetch_distance + 3; i < j; i += 1) {
    sa_uint_t p = (sa_uint_t)SA[i];
    sa_sint_t s = SAm[p >> 1];
    if (s < 0) {
      T[p] |= SAINT_MIN;
      f++;
      s = i + SAINT_MIN + f;
    }
    SAm[p >> 1] = s - f;
  }

  return f;
}

static void libsais_compact_unique_and_nonunique_lms_suffixes_32s(
    sa_sint_t* RESTRICT SA, sa_sint_t m, fast_sint_t* pl, fast_sint_t* pr,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_uint_t* RESTRICT SAl = (sa_uint_t*)&SA[0];
  sa_uint_t* RESTRICT SAr = (sa_uint_t*)&SA[0];

  fast_sint_t i, j, l = *pl - 1, r = *pr - 1;
  for (i = (fast_sint_t)m + omp_block_start + omp_block_size - 1,
      j = (fast_sint_t)m + omp_block_start + 3;
       i >= j; i -= 4) {
    libsais_prefetchr(&SA[i - prefetch_distance]);

    sa_uint_t p0 = (sa_uint_t)SA[i - 0];
    SAl[l] = p0 & SAINT_MAX;
    l -= (sa_sint_t)p0 < 0;
    SAr[r] = p0 - 1;
    r -= (sa_sint_t)p0 > 0;
    sa_uint_t p1 = (sa_uint_t)SA[i - 1];
    SAl[l] = p1 & SAINT_MAX;
    l -= (sa_sint_t)p1 < 0;
    SAr[r] = p1 - 1;
    r -= (sa_sint_t)p1 > 0;
    sa_uint_t p2 = (sa_uint_t)SA[i - 2];
    SAl[l] = p2 & SAINT_MAX;
    l -= (sa_sint_t)p2 < 0;
    SAr[r] = p2 - 1;
    r -= (sa_sint_t)p2 > 0;
    sa_uint_t p3 = (sa_uint_t)SA[i - 3];
    SAl[l] = p3 & SAINT_MAX;
    l -= (sa_sint_t)p3 < 0;
    SAr[r] = p3 - 1;
    r -= (sa_sint_t)p3 > 0;
  }

  for (j -= 3; i >= j; i -= 1) {
    sa_uint_t p = (sa_uint_t)SA[i];
    SAl[l] = p & SAINT_MAX;
    l -= (sa_sint_t)p < 0;
    SAr[r] = p - 1;
    r -= (sa_sint_t)p > 0;
  }

  *pl = l + 1;
  *pr = r + 1;
}

#if defined(LIBSAIS_OPENMP)

static sa_sint_t libsais_count_unique_suffixes(sa_sint_t* RESTRICT SA,
                                               sa_sint_t m,
                                               fast_sint_t omp_block_start,
                                               fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  sa_sint_t* RESTRICT SAm = &SA[m];

  fast_sint_t i, j;
  sa_sint_t f0 = 0, f1 = 0, f2 = 0, f3 = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchr(&SAm[((sa_uint_t)SA[i + prefetch_distance + 0]) >> 1]);
    libsais_prefetchr(&SAm[((sa_uint_t)SA[i + prefetch_distance + 1]) >> 1]);
    libsais_prefetchr(&SAm[((sa_uint_t)SA[i + prefetch_distance + 2]) >> 1]);
    libsais_prefetchr(&SAm[((sa_uint_t)SA[i + prefetch_distance + 3]) >> 1]);

    f0 += SAm[((sa_uint_t)SA[i + 0]) >> 1] < 0;
    f1 += SAm[((sa_uint_t)SA[i + 1]) >> 1] < 0;
    f2 += SAm[((sa_uint_t)SA[i + 2]) >> 1] < 0;
    f3 += SAm[((sa_uint_t)SA[i + 3]) >> 1] < 0;
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    f0 += SAm[((sa_uint_t)SA[i]) >> 1] < 0;
  }

  return f0 + f1 + f2 + f3;
}

#endif

static sa_sint_t libsais_renumber_unique_and_nonunique_lms_suffixes_32s_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t m,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t f = 0;

#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && m >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (m / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : m - omp_block_start;

    if (omp_num_threads == 1) {
      f = libsais_renumber_unique_and_nonunique_lms_suffixes_32s(
          T, SA, m, 0, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_count_unique_suffixes(SA, m, omp_block_start,
                                          omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t t, count = 0;
        for (t = 0; t < omp_thread_num; ++t) {
          count += thread_state[t].state.count;
        }

        if (omp_thread_num == omp_num_threads - 1) {
          f = (sa_sint_t)(count + thread_state[omp_thread_num].state.count);
        }

        libsais_renumber_unique_and_nonunique_lms_suffixes_32s(
            T, SA, m, (sa_sint_t)count, omp_block_start, omp_block_size);
      }
    }
#endif
  }

  return f;
}

static void libsais_compact_unique_and_nonunique_lms_suffixes_32s_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, sa_sint_t fs, sa_sint_t f,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 131072 && \
                                                  m < fs)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride =
        (((fast_sint_t)n >> 1) / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : ((fast_sint_t)n >> 1) - omp_block_start;

    if (omp_num_threads == 1) {
      fast_sint_t l = m, r = (fast_sint_t)n + (fast_sint_t)fs;
      libsais_compact_unique_and_nonunique_lms_suffixes_32s(
          SA, m, &l, &r, omp_block_start, omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.position =
            (fast_sint_t)m + ((fast_sint_t)n >> 1) + omp_block_start +
            omp_block_size;
        thread_state[omp_thread_num].state.count =
            (fast_sint_t)m + omp_block_start + omp_block_size;

        libsais_compact_unique_and_nonunique_lms_suffixes_32s(
            SA, m, &thread_state[omp_thread_num].state.position,
            &thread_state[omp_thread_num].state.count, omp_block_start,
            omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        fast_sint_t t, position;

        for (position = m, t = omp_num_threads - 1; t >= 0; --t) {
          fast_sint_t omp_block_end = t < omp_num_threads - 1
                                          ? omp_block_stride * (t + 1)
                                          : ((fast_sint_t)n >> 1);
          fast_sint_t count = ((fast_sint_t)m + ((fast_sint_t)n >> 1) +
                               omp_block_end - thread_state[t].state.position);

          if (count > 0) {
            position -= count;
            memcpy(&SA[position], &SA[thread_state[t].state.position],
                   (size_t)count * sizeof(sa_sint_t));
          }
        }

        for (position = (fast_sint_t)n + (fast_sint_t)fs,
            t = omp_num_threads - 1;
             t >= 0; --t) {
          fast_sint_t omp_block_end = t < omp_num_threads - 1
                                          ? omp_block_stride * (t + 1)
                                          : ((fast_sint_t)n >> 1);
          fast_sint_t count =
              ((fast_sint_t)m + omp_block_end - thread_state[t].state.count);

          if (count > 0) {
            position -= count;
            memcpy(&SA[position], &SA[thread_state[t].state.count],
                   (size_t)count * sizeof(sa_sint_t));
          }
        }
      }
    }
#endif
  }

  memcpy(&SA[(fast_sint_t)n + (fast_sint_t)fs - (fast_sint_t)m],
         &SA[(fast_sint_t)m - (fast_sint_t)f], (size_t)f * sizeof(sa_sint_t));
}

static sa_sint_t libsais_compact_lms_suffixes_32s_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    sa_sint_t fs, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t f = libsais_renumber_unique_and_nonunique_lms_suffixes_32s_omp(
      T, SA, m, threads, thread_state);
  libsais_compact_unique_and_nonunique_lms_suffixes_32s_omp(
      SA, n, m, fs, f, threads, thread_state);

  return f;
}

static void libsais_merge_unique_lms_suffixes_32s(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    fast_sint_t l, fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  const sa_sint_t* RESTRICT SAnm = &SA[(fast_sint_t)n - (fast_sint_t)m - 1 + l];

  sa_sint_t i, j;
  fast_sint_t tmp = *SAnm++;
  for (i = (sa_sint_t)omp_block_start,
      j = (sa_sint_t)omp_block_start + (sa_sint_t)omp_block_size - 6;
       i < j; i += 4) {
    libsais_prefetchr(&T[i + prefetch_distance]);

    sa_sint_t c0 = T[i + 0];
    if (c0 < 0) {
      T[i + 0] = c0 & SAINT_MAX;
      SA[tmp] = i + 0;
      i++;
      tmp = *SAnm++;
    }
    sa_sint_t c1 = T[i + 1];
    if (c1 < 0) {
      T[i + 1] = c1 & SAINT_MAX;
      SA[tmp] = i + 1;
      i++;
      tmp = *SAnm++;
    }
    sa_sint_t c2 = T[i + 2];
    if (c2 < 0) {
      T[i + 2] = c2 & SAINT_MAX;
      SA[tmp] = i + 2;
      i++;
      tmp = *SAnm++;
    }
    sa_sint_t c3 = T[i + 3];
    if (c3 < 0) {
      T[i + 3] = c3 & SAINT_MAX;
      SA[tmp] = i + 3;
      i++;
      tmp = *SAnm++;
    }
  }

  for (j += 6; i < j; i += 1) {
    sa_sint_t c = T[i];
    if (c < 0) {
      T[i] = c & SAINT_MAX;
      SA[tmp] = i;
      i++;
      tmp = *SAnm++;
    }
  }
}

static void libsais_merge_nonunique_lms_suffixes_32s(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, fast_sint_t l,
    fast_sint_t omp_block_start, fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  const sa_sint_t* RESTRICT SAnm = &SA[(fast_sint_t)n - (fast_sint_t)m - 1 + l];

  fast_sint_t i, j;
  sa_sint_t tmp = *SAnm++;
  for (i = omp_block_start, j = omp_block_start + omp_block_size - 3; i < j;
       i += 4) {
    libsais_prefetchr(&SA[i + prefetch_distance]);

    if (SA[i + 0] == 0) {
      SA[i + 0] = tmp;
      tmp = *SAnm++;
    }
    if (SA[i + 1] == 0) {
      SA[i + 1] = tmp;
      tmp = *SAnm++;
    }
    if (SA[i + 2] == 0) {
      SA[i + 2] = tmp;
      tmp = *SAnm++;
    }
    if (SA[i + 3] == 0) {
      SA[i + 3] = tmp;
      tmp = *SAnm++;
    }
  }

  for (j += 3; i < j; i += 1) {
    if (SA[i] == 0) {
      SA[i] = tmp;
      tmp = *SAnm++;
    }
  }
}

static void libsais_merge_unique_lms_suffixes_32s_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_merge_unique_lms_suffixes_32s(T, SA, n, m, 0, omp_block_start,
                                            omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_count_negative_marked_suffixes(T, omp_block_start,
                                                   omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t t, count = 0;
        for (t = 0; t < omp_thread_num; ++t) {
          count += thread_state[t].state.count;
        }

        libsais_merge_unique_lms_suffixes_32s(T, SA, n, m, count,
                                              omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

static void libsais_merge_nonunique_lms_suffixes_32s_omp(
    sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m, sa_sint_t f,
    sa_sint_t threads, LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && m >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);
    UNUSED(thread_state);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (m / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : m - omp_block_start;

    if (omp_num_threads == 1) {
      libsais_merge_nonunique_lms_suffixes_32s(SA, n, m, f, omp_block_start,
                                               omp_block_size);
    }
#if defined(LIBSAIS_OPENMP)
    else {
      {
        thread_state[omp_thread_num].state.count =
            libsais_count_zero_marked_suffixes(SA, omp_block_start,
                                               omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t t, count = f;
        for (t = 0; t < omp_thread_num; ++t) {
          count += thread_state[t].state.count;
        }

        libsais_merge_nonunique_lms_suffixes_32s(
            SA, n, m, count, omp_block_start, omp_block_size);
      }
    }
#endif
  }
}

static void libsais_merge_compacted_lms_suffixes_32s_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    sa_sint_t f, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  libsais_merge_unique_lms_suffixes_32s_omp(T, SA, n, m, threads, thread_state);
  libsais_merge_nonunique_lms_suffixes_32s_omp(SA, n, m, f, threads,
                                               thread_state);
}

static void libsais_reconstruct_compacted_lms_suffixes_32s_2k_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t m, sa_sint_t fs, sa_sint_t f, sa_sint_t* RESTRICT buckets,
    sa_sint_t local_buckets, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (f > 0) {
    memmove(&SA[n - m - 1], &SA[n + fs - m], (size_t)f * sizeof(sa_sint_t));

    libsais_count_and_gather_compacted_lms_suffixes_32s_2k_omp(
        T, SA, n, k, buckets, local_buckets, threads, thread_state);
    libsais_reconstruct_lms_suffixes_omp(SA, n, m - f, threads);

    memcpy(&SA[n - m - 1 + f], &SA[0],
           ((size_t)m - (size_t)f) * sizeof(sa_sint_t));
    memset(&SA[0], 0, (size_t)m * sizeof(sa_sint_t));

    libsais_merge_compacted_lms_suffixes_32s_omp(T, SA, n, m, f, threads,
                                                 thread_state);
  } else {
    libsais_count_and_gather_lms_suffixes_32s_2k(T, SA, n, k, buckets, 0, n);
    libsais_reconstruct_lms_suffixes_omp(SA, n, m, threads);
  }
}

static void libsais_reconstruct_compacted_lms_suffixes_32s_1k_omp(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t m,
    sa_sint_t fs, sa_sint_t f, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  if (f > 0) {
    memmove(&SA[n - m - 1], &SA[n + fs - m], (size_t)f * sizeof(sa_sint_t));

    libsais_gather_compacted_lms_suffixes_32s(T, SA, n);
    libsais_reconstruct_lms_suffixes_omp(SA, n, m - f, threads);

    memcpy(&SA[n - m - 1 + f], &SA[0],
           ((size_t)m - (size_t)f) * sizeof(sa_sint_t));
    memset(&SA[0], 0, (size_t)m * sizeof(sa_sint_t));

    libsais_merge_compacted_lms_suffixes_32s_omp(T, SA, n, m, f, threads,
                                                 thread_state);
  } else {
    libsais_gather_lms_suffixes_32s(T, SA, n);
    libsais_reconstruct_lms_suffixes_omp(SA, n, m, threads);
  }
}

static sa_sint_t libsais_main_32s_recursion(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t fs, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state,
    sa_sint_t* RESTRICT local_buffer) {
  fs = fs < (SAINT_MAX - n) ? fs : (SAINT_MAX - n);

  if (k > 0 && ((fs / k >= 6) || (LIBSAIS_LOCAL_BUFFER_SIZE / k >= 6))) {
    sa_sint_t alignment =
        (fs - 1024) / k >= 6 ? (sa_sint_t)1024 : (sa_sint_t)16;
    sa_sint_t* RESTRICT buckets =
        (fs - alignment) / k >= 6
            ? (sa_sint_t*)libsais_align_up(
                  &SA[n + fs - 6 * (fast_sint_t)k - alignment],
                  (size_t)alignment * sizeof(sa_sint_t))
            : &SA[n + fs - 6 * (fast_sint_t)k];
    buckets = (LIBSAIS_LOCAL_BUFFER_SIZE > fs) ? local_buffer : buckets;

    sa_sint_t m = libsais_count_and_gather_lms_suffixes_32s_4k_omp(
        T, SA, n, k, buckets, buckets == local_buffer, threads, thread_state);
    if (m > 1) {
      memset(SA, 0, ((size_t)n - (size_t)m) * sizeof(sa_sint_t));

      sa_sint_t first_lms_suffix = SA[n - m];
      sa_sint_t left_suffixes_count =
          libsais_initialize_buckets_for_lms_suffixes_radix_sort_32s_6k(
              T, k, buckets, first_lms_suffix);

      libsais_radix_sort_lms_suffixes_32s_6k_omp(
          T, SA, n, m, &buckets[4 * (fast_sint_t)k], threads, thread_state);

      if ((n / 8192) < k) {
        libsais_radix_sort_set_markers_32s_6k_omp(
            SA, k, &buckets[4 * (fast_sint_t)k], threads);
      }
      if (threads > 1 && n >= 65536) {
        memset(&SA[(fast_sint_t)n - (fast_sint_t)m], 0,
               (size_t)m * sizeof(sa_sint_t));
      }

      libsais_initialize_buckets_for_partial_sorting_32s_6k(
          T, k, buckets, first_lms_suffix, left_suffixes_count);
      libsais_induce_partial_order_32s_6k_omp(
          T, SA, n, k, buckets, first_lms_suffix, left_suffixes_count, threads,
          thread_state);

      sa_sint_t names =
          (n / 8192) < k
              ? libsais_renumber_and_mark_distinct_lms_suffixes_32s_4k_omp(
                    SA, n, m, threads, thread_state)
              : libsais_renumber_and_gather_lms_suffixes_omp(
                    SA, n, m, fs, threads, thread_state);

      if (names < m) {
        sa_sint_t f = (n / 8192) < k
                          ? libsais_compact_lms_suffixes_32s_omp(
                                T, SA, n, m, fs, threads, thread_state)
                          : 0;

        if (libsais_main_32s_recursion(SA + n + fs - m + f, SA, m - f,
                                       names - f, fs + n - 2 * m + f, threads,
                                       thread_state, local_buffer) != 0) {
          return -2;
        }

        libsais_reconstruct_compacted_lms_suffixes_32s_2k_omp(
            T, SA, n, k, m, fs, f, buckets, buckets == local_buffer, threads,
            thread_state);
      } else {
        libsais_count_lms_suffixes_32s_2k(T, n, k, buckets);
      }

      libsais_initialize_buckets_start_and_end_32s_4k(k, buckets);
      libsais_place_lms_suffixes_histogram_32s_4k(SA, n, k, m, buckets);
      libsais_induce_final_order_32s_4k(T, SA, n, k, buckets, threads,
                                        thread_state);
    } else {
      SA[0] = SA[n - 1];

      libsais_initialize_buckets_start_and_end_32s_6k(k, buckets);
      libsais_place_lms_suffixes_histogram_32s_6k(SA, n, k, m, buckets);
      libsais_induce_final_order_32s_6k(T, SA, n, k, buckets, threads,
                                        thread_state);
    }

    return 0;
  } else if (k > 0 && (n <= SAINT_MAX / 2) &&
             ((fs / k >= 4) || (LIBSAIS_LOCAL_BUFFER_SIZE / k >= 4))) {
    sa_sint_t alignment =
        (fs - 1024) / k >= 4 ? (sa_sint_t)1024 : (sa_sint_t)16;
    sa_sint_t* RESTRICT buckets =
        (fs - alignment) / k >= 4
            ? (sa_sint_t*)libsais_align_up(
                  &SA[n + fs - 4 * (fast_sint_t)k - alignment],
                  (size_t)alignment * sizeof(sa_sint_t))
            : &SA[n + fs - 4 * (fast_sint_t)k];
    buckets = (LIBSAIS_LOCAL_BUFFER_SIZE > fs) ? local_buffer : buckets;

    sa_sint_t m = libsais_count_and_gather_lms_suffixes_32s_2k_omp(
        T, SA, n, k, buckets, buckets == local_buffer, threads, thread_state);
    if (m > 1) {
      libsais_initialize_buckets_for_radix_and_partial_sorting_32s_4k(
          T, k, buckets, SA[n - m]);

      libsais_radix_sort_lms_suffixes_32s_2k_omp(T, SA, n, m, &buckets[1],
                                                 threads, thread_state);
      libsais_radix_sort_set_markers_32s_4k_omp(SA, k, &buckets[1], threads);

      libsais_place_lms_suffixes_interval_32s_4k(SA, n, k, m - 1, buckets);
      libsais_induce_partial_order_32s_4k_omp(T, SA, n, k, buckets, threads,
                                              thread_state);

      sa_sint_t names =
          libsais_renumber_and_mark_distinct_lms_suffixes_32s_4k_omp(
              SA, n, m, threads, thread_state);
      if (names < m) {
        sa_sint_t f = libsais_compact_lms_suffixes_32s_omp(
            T, SA, n, m, fs, threads, thread_state);

        if (libsais_main_32s_recursion(SA + n + fs - m + f, SA, m - f,
                                       names - f, fs + n - 2 * m + f, threads,
                                       thread_state, local_buffer) != 0) {
          return -2;
        }

        libsais_reconstruct_compacted_lms_suffixes_32s_2k_omp(
            T, SA, n, k, m, fs, f, buckets, buckets == local_buffer, threads,
            thread_state);
      } else {
        libsais_count_lms_suffixes_32s_2k(T, n, k, buckets);
      }
    } else {
      SA[0] = SA[n - 1];
    }

    libsais_initialize_buckets_start_and_end_32s_4k(k, buckets);
    libsais_place_lms_suffixes_histogram_32s_4k(SA, n, k, m, buckets);
    libsais_induce_final_order_32s_4k(T, SA, n, k, buckets, threads,
                                      thread_state);

    return 0;
  } else if (k > 0 && ((fs / k >= 2) || (LIBSAIS_LOCAL_BUFFER_SIZE / k >= 2))) {
    sa_sint_t alignment =
        (fs - 1024) / k >= 2 ? (sa_sint_t)1024 : (sa_sint_t)16;
    sa_sint_t* RESTRICT buckets =
        (fs - alignment) / k >= 2
            ? (sa_sint_t*)libsais_align_up(
                  &SA[n + fs - 2 * (fast_sint_t)k - alignment],
                  (size_t)alignment * sizeof(sa_sint_t))
            : &SA[n + fs - 2 * (fast_sint_t)k];
    buckets = (LIBSAIS_LOCAL_BUFFER_SIZE > fs) ? local_buffer : buckets;

    sa_sint_t m = libsais_count_and_gather_lms_suffixes_32s_2k_omp(
        T, SA, n, k, buckets, buckets == local_buffer, threads, thread_state);
    if (m > 1) {
      libsais_initialize_buckets_for_lms_suffixes_radix_sort_32s_2k(
          T, k, buckets, SA[n - m]);

      libsais_radix_sort_lms_suffixes_32s_2k_omp(T, SA, n, m, &buckets[1],
                                                 threads, thread_state);
      libsais_place_lms_suffixes_interval_32s_2k(SA, n, k, m - 1, buckets);

      libsais_initialize_buckets_start_and_end_32s_2k(k, buckets);
      libsais_induce_partial_order_32s_2k_omp(T, SA, n, k, buckets, threads,
                                              thread_state);

      sa_sint_t names =
          libsais_renumber_and_mark_distinct_lms_suffixes_32s_1k_omp(
              T, SA, n, m, threads);
      if (names < m) {
        sa_sint_t f = libsais_compact_lms_suffixes_32s_omp(
            T, SA, n, m, fs, threads, thread_state);

        if (libsais_main_32s_recursion(SA + n + fs - m + f, SA, m - f,
                                       names - f, fs + n - 2 * m + f, threads,
                                       thread_state, local_buffer) != 0) {
          return -2;
        }

        libsais_reconstruct_compacted_lms_suffixes_32s_2k_omp(
            T, SA, n, k, m, fs, f, buckets, buckets == local_buffer, threads,
            thread_state);
      } else {
        libsais_count_lms_suffixes_32s_2k(T, n, k, buckets);
      }
    } else {
      SA[0] = SA[n - 1];
    }

    libsais_initialize_buckets_end_32s_2k(k, buckets);
    libsais_place_lms_suffixes_histogram_32s_2k(SA, n, k, m, buckets);

    libsais_initialize_buckets_start_and_end_32s_2k(k, buckets);
    libsais_induce_final_order_32s_2k(T, SA, n, k, buckets, threads,
                                      thread_state);

    return 0;
  } else {
    sa_sint_t* buffer = fs < k ? (sa_sint_t*)libsais_alloc_aligned(
                                     (size_t)k * sizeof(sa_sint_t), 4096)
                               : (sa_sint_t*)NULL;

    sa_sint_t alignment = fs - 1024 >= k ? (sa_sint_t)1024 : (sa_sint_t)16;
    sa_sint_t* RESTRICT buckets =
        fs - alignment >= k ? (sa_sint_t*)libsais_align_up(
                                  &SA[n + fs - k - alignment],
                                  (size_t)alignment * sizeof(sa_sint_t))
        : fs >= k           ? &SA[n + fs - k]
                            : buffer;

    if (buckets == NULL) {
      return -2;
    }

    memset(SA, 0, (size_t)n * sizeof(sa_sint_t));

    libsais_count_suffixes_32s(T, n, k, buckets);
    libsais_initialize_buckets_end_32s_1k(k, buckets);

    sa_sint_t m = libsais_radix_sort_lms_suffixes_32s_1k(T, SA, n, buckets);
    if (m > 1) {
      libsais_induce_partial_order_32s_1k_omp(T, SA, n, k, buckets, threads,
                                              thread_state);

      sa_sint_t names =
          libsais_renumber_and_mark_distinct_lms_suffixes_32s_1k_omp(
              T, SA, n, m, threads);
      if (names < m) {
        if (buffer != NULL) {
          libsais_free_aligned(buffer);
          buckets = NULL;
        }

        sa_sint_t f = libsais_compact_lms_suffixes_32s_omp(
            T, SA, n, m, fs, threads, thread_state);

        if (libsais_main_32s_recursion(SA + n + fs - m + f, SA, m - f,
                                       names - f, fs + n - 2 * m + f, threads,
                                       thread_state, local_buffer) != 0) {
          return -2;
        }

        libsais_reconstruct_compacted_lms_suffixes_32s_1k_omp(
            T, SA, n, m, fs, f, threads, thread_state);

        if (buckets == NULL) {
          buckets = buffer = (sa_sint_t*)libsais_alloc_aligned(
              (size_t)k * sizeof(sa_sint_t), 4096);
        }
        if (buckets == NULL) {
          return -2;
        }
      }

      libsais_count_suffixes_32s(T, n, k, buckets);
      libsais_initialize_buckets_end_32s_1k(k, buckets);
      libsais_place_lms_suffixes_interval_32s_1k(T, SA, k, m, buckets);
    }

    libsais_induce_final_order_32s_1k(T, SA, n, k, buckets, threads,
                                      thread_state);
    libsais_free_aligned(buffer);

    return 0;
  }
}

static sa_sint_t libsais_main_32s_entry(
    sa_sint_t* RESTRICT T, sa_sint_t* RESTRICT SA, sa_sint_t n, sa_sint_t k,
    sa_sint_t fs, sa_sint_t threads,
    LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  sa_sint_t local_buffer[2 * LIBSAIS_LOCAL_BUFFER_SIZE];

  return libsais_main_32s_recursion(T, SA, n, k, fs, threads, thread_state,
                                    local_buffer + LIBSAIS_LOCAL_BUFFER_SIZE);
}

static sa_sint_t libsais_main_8u(const uint8_t* T, sa_sint_t* SA, sa_sint_t n,
                                 sa_sint_t* RESTRICT buckets, sa_sint_t flags,
                                 sa_sint_t r, sa_sint_t* RESTRICT I,
                                 sa_sint_t fs, sa_sint_t* freq,
                                 sa_sint_t threads,
                                 LIBSAIS_THREAD_STATE* RESTRICT thread_state) {
  fs = fs < (SAINT_MAX - n) ? fs : (SAINT_MAX - n);

  sa_sint_t m = libsais_count_and_gather_lms_suffixes_8u_omp(
      T, SA, n, buckets, threads, thread_state);
  sa_sint_t k = libsais_initialize_buckets_start_and_end_8u(buckets, freq);

  if ((flags & LIBSAIS_FLAGS_GSA) &&
      (buckets[0] != 0 || buckets[2] != 0 || buckets[3] != 1)) {
    return -1;
  }

  if (m > 0) {
    sa_sint_t first_lms_suffix = SA[n - m];
    sa_sint_t left_suffixes_count =
        libsais_initialize_buckets_for_lms_suffixes_radix_sort_8u(
            T, buckets, first_lms_suffix);

    if (threads > 1 && n >= 65536) {
      memset(SA, 0, ((size_t)n - (size_t)m) * sizeof(sa_sint_t));
    }
    libsais_radix_sort_lms_suffixes_8u_omp(T, SA, n, m, flags, buckets, threads,
                                           thread_state);
    if (threads > 1 && n >= 65536) {
      memset(&SA[(fast_sint_t)n - (fast_sint_t)m], 0,
             (size_t)m * sizeof(sa_sint_t));
    }

    libsais_initialize_buckets_for_partial_sorting_8u(
        T, buckets, first_lms_suffix, left_suffixes_count);
    libsais_induce_partial_order_8u_omp(T, SA, n, k, flags, buckets,
                                        first_lms_suffix, left_suffixes_count,
                                        threads, thread_state);

    sa_sint_t names = libsais_renumber_and_gather_lms_suffixes_omp(
        SA, n, m, fs, threads, thread_state);
    if (names < m) {
      if (libsais_main_32s_entry(SA + n + fs - m, SA, m, names, fs + n - 2 * m,
                                 threads, thread_state) != 0) {
        return -2;
      }

      libsais_gather_lms_suffixes_8u_omp(T, SA, n, threads, thread_state);
      libsais_reconstruct_lms_suffixes_omp(SA, n, m, threads);
    }

    libsais_place_lms_suffixes_interval_8u(SA, n, m, flags, buckets);
  } else {
    memset(SA, 0, (size_t)n * sizeof(sa_sint_t));
  }

  return libsais_induce_final_order_8u_omp(T, SA, n, k, flags, r, I, buckets,
                                           threads, thread_state);
}

static sa_sint_t libsais_main(const uint8_t* T, sa_sint_t* SA, sa_sint_t n,
                              sa_sint_t flags, sa_sint_t r, sa_sint_t* I,
                              sa_sint_t fs, sa_sint_t* freq,
                              sa_sint_t threads) {
  LIBSAIS_THREAD_STATE* RESTRICT thread_state =
      threads > 1 ? libsais_alloc_thread_state(threads) : NULL;
  sa_sint_t* RESTRICT buckets = (sa_sint_t*)libsais_alloc_aligned(
      (size_t)8 * ALPHABET_SIZE * sizeof(sa_sint_t), 4096);

  sa_sint_t index = buckets != NULL && (thread_state != NULL || threads == 1)
                        ? libsais_main_8u(T, SA, n, buckets, flags, r, I, fs,
                                          freq, threads, thread_state)
                        : -2;

  libsais_free_aligned(buckets);
  libsais_free_thread_state(thread_state);

  return index;
}

static sa_sint_t libsais_main_int(sa_sint_t* T, sa_sint_t* SA, sa_sint_t n,
                                  sa_sint_t k, sa_sint_t fs,
                                  sa_sint_t threads) {
  LIBSAIS_THREAD_STATE* RESTRICT thread_state =
      threads > 1 ? libsais_alloc_thread_state(threads) : NULL;

  sa_sint_t index =
      thread_state != NULL || threads == 1
          ? libsais_main_32s_entry(T, SA, n, k, fs, threads, thread_state)
          : -2;

  libsais_free_thread_state(thread_state);

  return index;
}

static sa_sint_t libsais_main_ctx(const LIBSAIS_CONTEXT* ctx, const uint8_t* T,
                                  sa_sint_t* SA, sa_sint_t n, sa_sint_t flags,
                                  sa_sint_t r, sa_sint_t* I, sa_sint_t fs,
                                  sa_sint_t* freq) {
  return ctx != NULL && (ctx->buckets != NULL &&
                         (ctx->thread_state != NULL || ctx->threads == 1))
             ? libsais_main_8u(T, SA, n, ctx->buckets, flags, r, I, fs, freq,
                               (sa_sint_t)ctx->threads, ctx->thread_state)
             : -2;
}

static void libsais_bwt_copy_8u(uint8_t* RESTRICT U, sa_sint_t* RESTRICT A,
                                sa_sint_t n) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = 0, j = (fast_sint_t)n - 7; i < j; i += 8) {
    libsais_prefetchr(&A[i + prefetch_distance]);

    U[i + 0] = (uint8_t)A[i + 0];
    U[i + 1] = (uint8_t)A[i + 1];
    U[i + 2] = (uint8_t)A[i + 2];
    U[i + 3] = (uint8_t)A[i + 3];
    U[i + 4] = (uint8_t)A[i + 4];
    U[i + 5] = (uint8_t)A[i + 5];
    U[i + 6] = (uint8_t)A[i + 6];
    U[i + 7] = (uint8_t)A[i + 7];
  }

  for (j += 7; i < j; i += 1) {
    U[i] = (uint8_t)A[i];
  }
}

static void libsais_bwt_copy_8u_omp(uint8_t* RESTRICT U, sa_sint_t* RESTRICT A,
                                    sa_sint_t n, sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
    fast_sint_t omp_block_stride = ((fast_sint_t)n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : (fast_sint_t)n - omp_block_start;
#else
    UNUSED(threads);

    fast_sint_t omp_block_start = 0;
    fast_sint_t omp_block_size = (fast_sint_t)n;
#endif

    libsais_bwt_copy_8u(U + omp_block_start, A + omp_block_start,
                        (sa_sint_t)omp_block_size);
  }
}

void* libsais_create_ctx(void) { return (void*)libsais_create_ctx_main(1); }

void libsais_free_ctx(void* ctx) {
  libsais_free_ctx_main((LIBSAIS_CONTEXT*)ctx);
}

int32_t libsais(const uint8_t* T, int32_t* SA, int32_t n, int32_t fs,
                int32_t* freq) {
  if ((T == NULL) || (SA == NULL) || (n < 0) || (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      SA[0] = 0;
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return 0;
  }

  return libsais_main(T, SA, n, LIBSAIS_FLAGS_NONE, 0, NULL, fs, freq, 1);
}

int32_t libsais_gsa(const uint8_t* T, int32_t* SA, int32_t n, int32_t fs,
                    int32_t* freq) {
  if ((T == NULL) || (SA == NULL) || (n < 0) || (n > 0 && T[n - 1] != 0) ||
      (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      SA[0] = 0;
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return 0;
  }

  return libsais_main(T, SA, n, LIBSAIS_FLAGS_GSA, 0, NULL, fs, freq, 1);
}

int32_t libsais_int(int32_t* T, int32_t* SA, int32_t n, int32_t k, int32_t fs) {
  if ((T == NULL) || (SA == NULL) || (n < 0) || (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      SA[0] = 0;
    }
    return 0;
  }

  return libsais_main_int(T, SA, n, k, fs, 1);
}

int32_t libsais_ctx(const void* ctx, const uint8_t* T, int32_t* SA, int32_t n,
                    int32_t fs, int32_t* freq) {
  if ((ctx == NULL) || (T == NULL) || (SA == NULL) || (n < 0) || (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      SA[0] = 0;
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return 0;
  }

  return libsais_main_ctx((const LIBSAIS_CONTEXT*)ctx, T, SA, n,
                          LIBSAIS_FLAGS_NONE, 0, NULL, fs, freq);
}

int32_t libsais_gsa_ctx(const void* ctx, const uint8_t* T, int32_t* SA,
                        int32_t n, int32_t fs, int32_t* freq) {
  if ((ctx == NULL) || (T == NULL) || (SA == NULL) || (n < 0) ||
      (n > 0 && T[n - 1] != 0) || (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      SA[0] = 0;
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return 0;
  }

  return libsais_main_ctx((const LIBSAIS_CONTEXT*)ctx, T, SA, n,
                          LIBSAIS_FLAGS_GSA, 0, NULL, fs, freq);
}

int32_t libsais_bwt(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                    int32_t fs, int32_t* freq) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) || (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      U[0] = T[0];
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return n;
  }

  sa_sint_t index =
      libsais_main(T, A, n, LIBSAIS_FLAGS_BWT, 0, NULL, fs, freq, 1);
  if (index >= 0) {
    index++;

    U[0] = T[n - 1];
    libsais_bwt_copy_8u_omp(U + 1, A, index - 1, 1);
    libsais_bwt_copy_8u_omp(U + index, A + index, n - index, 1);
  }

  return index;
}

int32_t libsais_bwt_aux(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                        int32_t fs, int32_t* freq, int32_t r, int32_t* I) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) || (fs < 0) ||
      (r < 2) || ((r & (r - 1)) != 0) || (I == NULL)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      U[0] = T[0];
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    I[0] = n;
    return 0;
  }

  sa_sint_t index = libsais_main(T, A, n, LIBSAIS_FLAGS_BWT, r, I, fs, freq, 1);
  if (index == 0) {
    U[0] = T[n - 1];
    libsais_bwt_copy_8u_omp(U + 1, A, I[0] - 1, 1);
    libsais_bwt_copy_8u_omp(U + I[0], A + I[0], n - I[0], 1);
  }

  return index;
}

int32_t libsais_bwt_ctx(const void* ctx, const uint8_t* T, uint8_t* U,
                        int32_t* A, int32_t n, int32_t fs, int32_t* freq) {
  if ((ctx == NULL) || (T == NULL) || (U == NULL) || (A == NULL) || (n < 0) ||
      (fs < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      U[0] = T[0];
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return n;
  }

  sa_sint_t index = libsais_main_ctx((const LIBSAIS_CONTEXT*)ctx, T, A, n,
                                     LIBSAIS_FLAGS_BWT, 0, NULL, fs, freq);
  if (index >= 0) {
    index++;

    U[0] = T[n - 1];
    libsais_bwt_copy_8u_omp(U + 1, A, index - 1,
                            (sa_sint_t)((const LIBSAIS_CONTEXT*)ctx)->threads);
    libsais_bwt_copy_8u_omp(U + index, A + index, n - index,
                            (sa_sint_t)((const LIBSAIS_CONTEXT*)ctx)->threads);
  }

  return index;
}

int32_t libsais_bwt_aux_ctx(const void* ctx, const uint8_t* T, uint8_t* U,
                            int32_t* A, int32_t n, int32_t fs, int32_t* freq,
                            int32_t r, int32_t* I) {
  if ((ctx == NULL) || (T == NULL) || (U == NULL) || (A == NULL) || (n < 0) ||
      (fs < 0) || (r < 2) || ((r & (r - 1)) != 0) || (I == NULL)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      U[0] = T[0];
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    I[0] = n;
    return 0;
  }

  sa_sint_t index = libsais_main_ctx((const LIBSAIS_CONTEXT*)ctx, T, A, n,
                                     LIBSAIS_FLAGS_BWT, r, I, fs, freq);
  if (index == 0) {
    U[0] = T[n - 1];
    libsais_bwt_copy_8u_omp(U + 1, A, I[0] - 1,
                            (sa_sint_t)((const LIBSAIS_CONTEXT*)ctx)->threads);
    libsais_bwt_copy_8u_omp(U + I[0], A + I[0], n - I[0],
                            (sa_sint_t)((const LIBSAIS_CONTEXT*)ctx)->threads);
  }

  return index;
}

#if defined(LIBSAIS_OPENMP)

void* libsais_create_ctx_omp(int32_t threads) {
  if (threads < 0) {
    return NULL;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  return (void*)libsais_create_ctx_main(threads);
}

int32_t libsais_omp(const uint8_t* T, int32_t* SA, int32_t n, int32_t fs,
                    int32_t* freq, int32_t threads) {
  if ((T == NULL) || (SA == NULL) || (n < 0) || (fs < 0) || (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      SA[0] = 0;
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  return libsais_main(T, SA, n, LIBSAIS_FLAGS_NONE, 0, NULL, fs, freq, threads);
}

int32_t libsais_gsa_omp(const uint8_t* T, int32_t* SA, int32_t n, int32_t fs,
                        int32_t* freq, int32_t threads) {
  if ((T == NULL) || (SA == NULL) || (n < 0) || (n > 0 && T[n - 1] != 0) ||
      (fs < 0) || (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      SA[0] = 0;
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  return libsais_main(T, SA, n, LIBSAIS_FLAGS_GSA, 0, NULL, fs, freq, threads);
}

int32_t libsais_int_omp(int32_t* T, int32_t* SA, int32_t n, int32_t k,
                        int32_t fs, int32_t threads) {
  if ((T == NULL) || (SA == NULL) || (n < 0) || (fs < 0) || (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      SA[0] = 0;
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  return libsais_main_int(T, SA, n, k, fs, threads);
}

int32_t libsais_bwt_omp(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                        int32_t fs, int32_t* freq, int32_t threads) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) || (fs < 0) ||
      (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      U[0] = T[0];
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    return n;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  sa_sint_t index =
      libsais_main(T, A, n, LIBSAIS_FLAGS_BWT, 0, NULL, fs, freq, threads);
  if (index >= 0) {
    index++;

    U[0] = T[n - 1];
    libsais_bwt_copy_8u_omp(U + 1, A, index - 1, threads);
    libsais_bwt_copy_8u_omp(U + index, A + index, n - index, threads);
  }

  return index;
}

int32_t libsais_bwt_aux_omp(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                            int32_t fs, int32_t* freq, int32_t r, int32_t* I,
                            int32_t threads) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) || (fs < 0) ||
      (r < 2) || ((r & (r - 1)) != 0) || (I == NULL) || (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (freq != NULL) {
      memset(freq, 0, ALPHABET_SIZE * sizeof(int32_t));
    }
    if (n == 1) {
      U[0] = T[0];
      if (freq != NULL) {
        freq[T[0]]++;
      }
    }
    I[0] = n;
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  sa_sint_t index =
      libsais_main(T, A, n, LIBSAIS_FLAGS_BWT, r, I, fs, freq, threads);
  if (index == 0) {
    U[0] = T[n - 1];
    libsais_bwt_copy_8u_omp(U + 1, A, I[0] - 1, threads);
    libsais_bwt_copy_8u_omp(U + I[0], A + I[0], n - I[0], threads);
  }

  return index;
}

#endif

static LIBSAIS_UNBWT_CONTEXT* libsais_unbwt_create_ctx_main(sa_sint_t threads) {
  LIBSAIS_UNBWT_CONTEXT* RESTRICT ctx =
      (LIBSAIS_UNBWT_CONTEXT*)libsais_alloc_aligned(
          sizeof(LIBSAIS_UNBWT_CONTEXT), 64);
  sa_uint_t* RESTRICT bucket2 = (sa_uint_t*)libsais_alloc_aligned(
      ALPHABET_SIZE * ALPHABET_SIZE * sizeof(sa_uint_t), 4096);
  uint16_t* RESTRICT fastbits = (uint16_t*)libsais_alloc_aligned(
      (1 + (1 << UNBWT_FASTBITS)) * sizeof(uint16_t), 4096);
  sa_uint_t* RESTRICT buckets =
      threads > 1 ? (sa_uint_t*)libsais_alloc_aligned(
                        (size_t)threads *
                            (ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE)) *
                            sizeof(sa_uint_t),
                        4096)
                  : NULL;

  if (ctx != NULL && bucket2 != NULL && fastbits != NULL &&
      (buckets != NULL || threads == 1)) {
    ctx->bucket2 = bucket2;
    ctx->fastbits = fastbits;
    ctx->buckets = buckets;
    ctx->threads = threads;

    return ctx;
  }

  libsais_free_aligned(buckets);
  libsais_free_aligned(fastbits);
  libsais_free_aligned(bucket2);
  libsais_free_aligned(ctx);

  return NULL;
}

static void libsais_unbwt_free_ctx_main(LIBSAIS_UNBWT_CONTEXT* ctx) {
  if (ctx != NULL) {
    libsais_free_aligned(ctx->buckets);
    libsais_free_aligned(ctx->fastbits);
    libsais_free_aligned(ctx->bucket2);
    libsais_free_aligned(ctx);
  }
}

static void libsais_unbwt_compute_histogram(const uint8_t* RESTRICT T,
                                            fast_sint_t n,
                                            sa_uint_t* RESTRICT count) {
  const fast_sint_t prefetch_distance = 256;

  const uint8_t* RESTRICT T_p = T;

  if (n >= 1024) {
    sa_uint_t copy[4 * (ALPHABET_SIZE + 16)];

    memset(copy, 0, (size_t)4 * (ALPHABET_SIZE + 16) * sizeof(sa_uint_t));

    sa_uint_t* RESTRICT copy0 = copy + 0 * (ALPHABET_SIZE + 16);
    sa_uint_t* RESTRICT copy1 = copy + 1 * (ALPHABET_SIZE + 16);
    sa_uint_t* RESTRICT copy2 = copy + 2 * (ALPHABET_SIZE + 16);
    sa_uint_t* RESTRICT copy3 = copy + 3 * (ALPHABET_SIZE + 16);

    for (; T_p < (uint8_t*)((ptrdiff_t)(T + 63) & (-64)); T_p += 1) {
      copy0[T_p[0]]++;
    }

    fast_uint_t x = ((const uint32_t*)(const void*)T_p)[0],
                y = ((const uint32_t*)(const void*)T_p)[1];

    for (; T_p < (uint8_t*)((ptrdiff_t)(T + n - 8) & (-64)); T_p += 64) {
      libsais_prefetchr(&T_p[prefetch_distance]);

      fast_uint_t z = ((const uint32_t*)(const void*)T_p)[2],
                  w = ((const uint32_t*)(const void*)T_p)[3];
      copy0[(uint8_t)x]++;
      x >>= 8;
      copy1[(uint8_t)x]++;
      x >>= 8;
      copy2[(uint8_t)x]++;
      x >>= 8;
      copy3[x]++;
      copy0[(uint8_t)y]++;
      y >>= 8;
      copy1[(uint8_t)y]++;
      y >>= 8;
      copy2[(uint8_t)y]++;
      y >>= 8;
      copy3[y]++;

      x = ((const uint32_t*)(const void*)T_p)[4];
      y = ((const uint32_t*)(const void*)T_p)[5];
      copy0[(uint8_t)z]++;
      z >>= 8;
      copy1[(uint8_t)z]++;
      z >>= 8;
      copy2[(uint8_t)z]++;
      z >>= 8;
      copy3[z]++;
      copy0[(uint8_t)w]++;
      w >>= 8;
      copy1[(uint8_t)w]++;
      w >>= 8;
      copy2[(uint8_t)w]++;
      w >>= 8;
      copy3[w]++;

      z = ((const uint32_t*)(const void*)T_p)[6];
      w = ((const uint32_t*)(const void*)T_p)[7];
      copy0[(uint8_t)x]++;
      x >>= 8;
      copy1[(uint8_t)x]++;
      x >>= 8;
      copy2[(uint8_t)x]++;
      x >>= 8;
      copy3[x]++;
      copy0[(uint8_t)y]++;
      y >>= 8;
      copy1[(uint8_t)y]++;
      y >>= 8;
      copy2[(uint8_t)y]++;
      y >>= 8;
      copy3[y]++;

      x = ((const uint32_t*)(const void*)T_p)[8];
      y = ((const uint32_t*)(const void*)T_p)[9];
      copy0[(uint8_t)z]++;
      z >>= 8;
      copy1[(uint8_t)z]++;
      z >>= 8;
      copy2[(uint8_t)z]++;
      z >>= 8;
      copy3[z]++;
      copy0[(uint8_t)w]++;
      w >>= 8;
      copy1[(uint8_t)w]++;
      w >>= 8;
      copy2[(uint8_t)w]++;
      w >>= 8;
      copy3[w]++;

      z = ((const uint32_t*)(const void*)T_p)[10];
      w = ((const uint32_t*)(const void*)T_p)[11];
      copy0[(uint8_t)x]++;
      x >>= 8;
      copy1[(uint8_t)x]++;
      x >>= 8;
      copy2[(uint8_t)x]++;
      x >>= 8;
      copy3[x]++;
      copy0[(uint8_t)y]++;
      y >>= 8;
      copy1[(uint8_t)y]++;
      y >>= 8;
      copy2[(uint8_t)y]++;
      y >>= 8;
      copy3[y]++;

      x = ((const uint32_t*)(const void*)T_p)[12];
      y = ((const uint32_t*)(const void*)T_p)[13];
      copy0[(uint8_t)z]++;
      z >>= 8;
      copy1[(uint8_t)z]++;
      z >>= 8;
      copy2[(uint8_t)z]++;
      z >>= 8;
      copy3[z]++;
      copy0[(uint8_t)w]++;
      w >>= 8;
      copy1[(uint8_t)w]++;
      w >>= 8;
      copy2[(uint8_t)w]++;
      w >>= 8;
      copy3[w]++;

      z = ((const uint32_t*)(const void*)T_p)[14];
      w = ((const uint32_t*)(const void*)T_p)[15];
      copy0[(uint8_t)x]++;
      x >>= 8;
      copy1[(uint8_t)x]++;
      x >>= 8;
      copy2[(uint8_t)x]++;
      x >>= 8;
      copy3[x]++;
      copy0[(uint8_t)y]++;
      y >>= 8;
      copy1[(uint8_t)y]++;
      y >>= 8;
      copy2[(uint8_t)y]++;
      y >>= 8;
      copy3[y]++;

      x = ((const uint32_t*)(const void*)T_p)[16];
      y = ((const uint32_t*)(const void*)T_p)[17];
      copy0[(uint8_t)z]++;
      z >>= 8;
      copy1[(uint8_t)z]++;
      z >>= 8;
      copy2[(uint8_t)z]++;
      z >>= 8;
      copy3[z]++;
      copy0[(uint8_t)w]++;
      w >>= 8;
      copy1[(uint8_t)w]++;
      w >>= 8;
      copy2[(uint8_t)w]++;
      w >>= 8;
      copy3[w]++;
    }

    copy0[(uint8_t)x]++;
    x >>= 8;
    copy1[(uint8_t)x]++;
    x >>= 8;
    copy2[(uint8_t)x]++;
    x >>= 8;
    copy3[x]++;
    copy0[(uint8_t)y]++;
    y >>= 8;
    copy1[(uint8_t)y]++;
    y >>= 8;
    copy2[(uint8_t)y]++;
    y >>= 8;
    copy3[y]++;

    T_p += 8;

    fast_uint_t i;
    for (i = 0; i < ALPHABET_SIZE; i++) {
      count[i] += copy0[i] + copy1[i] + copy2[i] + copy3[i];
    }
  }

  for (; T_p < T + n; T_p += 1) {
    count[T_p[0]]++;
  }
}

static void libsais_unbwt_transpose_bucket2(sa_uint_t* RESTRICT bucket2) {
  fast_uint_t x, y, c, d;
  for (x = 0; x != ALPHABET_SIZE; x += 16) {
    for (c = x; c != x + 16; ++c) {
      for (d = c + 1; d != x + 16; ++d) {
        sa_uint_t tmp = bucket2[(d << 8) + c];
        bucket2[(d << 8) + c] = bucket2[(c << 8) + d];
        bucket2[(c << 8) + d] = tmp;
      }
    }

    for (y = x + 16; y != ALPHABET_SIZE; y += 16) {
      for (c = x; c != x + 16; ++c) {
        sa_uint_t* bucket2_yc = &bucket2[(y << 8) + c];
        sa_uint_t* bucket2_cy = &bucket2[(c << 8) + y];

        sa_uint_t tmp00 = bucket2_yc[0 * 256];
        bucket2_yc[0 * 256] = bucket2_cy[0];
        bucket2_cy[0] = tmp00;
        sa_uint_t tmp01 = bucket2_yc[1 * 256];
        bucket2_yc[1 * 256] = bucket2_cy[1];
        bucket2_cy[1] = tmp01;
        sa_uint_t tmp02 = bucket2_yc[2 * 256];
        bucket2_yc[2 * 256] = bucket2_cy[2];
        bucket2_cy[2] = tmp02;
        sa_uint_t tmp03 = bucket2_yc[3 * 256];
        bucket2_yc[3 * 256] = bucket2_cy[3];
        bucket2_cy[3] = tmp03;
        sa_uint_t tmp04 = bucket2_yc[4 * 256];
        bucket2_yc[4 * 256] = bucket2_cy[4];
        bucket2_cy[4] = tmp04;
        sa_uint_t tmp05 = bucket2_yc[5 * 256];
        bucket2_yc[5 * 256] = bucket2_cy[5];
        bucket2_cy[5] = tmp05;
        sa_uint_t tmp06 = bucket2_yc[6 * 256];
        bucket2_yc[6 * 256] = bucket2_cy[6];
        bucket2_cy[6] = tmp06;
        sa_uint_t tmp07 = bucket2_yc[7 * 256];
        bucket2_yc[7 * 256] = bucket2_cy[7];
        bucket2_cy[7] = tmp07;
        sa_uint_t tmp08 = bucket2_yc[8 * 256];
        bucket2_yc[8 * 256] = bucket2_cy[8];
        bucket2_cy[8] = tmp08;
        sa_uint_t tmp09 = bucket2_yc[9 * 256];
        bucket2_yc[9 * 256] = bucket2_cy[9];
        bucket2_cy[9] = tmp09;
        sa_uint_t tmp10 = bucket2_yc[10 * 256];
        bucket2_yc[10 * 256] = bucket2_cy[10];
        bucket2_cy[10] = tmp10;
        sa_uint_t tmp11 = bucket2_yc[11 * 256];
        bucket2_yc[11 * 256] = bucket2_cy[11];
        bucket2_cy[11] = tmp11;
        sa_uint_t tmp12 = bucket2_yc[12 * 256];
        bucket2_yc[12 * 256] = bucket2_cy[12];
        bucket2_cy[12] = tmp12;
        sa_uint_t tmp13 = bucket2_yc[13 * 256];
        bucket2_yc[13 * 256] = bucket2_cy[13];
        bucket2_cy[13] = tmp13;
        sa_uint_t tmp14 = bucket2_yc[14 * 256];
        bucket2_yc[14 * 256] = bucket2_cy[14];
        bucket2_cy[14] = tmp14;
        sa_uint_t tmp15 = bucket2_yc[15 * 256];
        bucket2_yc[15 * 256] = bucket2_cy[15];
        bucket2_cy[15] = tmp15;
      }
    }
  }
}

static void libsais_unbwt_compute_bigram_histogram_single(
    const uint8_t* RESTRICT T, sa_uint_t* RESTRICT bucket1,
    sa_uint_t* RESTRICT bucket2, fast_uint_t index) {
  fast_uint_t sum, c;
  for (sum = 1, c = 0; c < ALPHABET_SIZE; ++c) {
    fast_uint_t prev = sum;
    sum += bucket1[c];
    bucket1[c] = (sa_uint_t)prev;
    if (prev != sum) {
      sa_uint_t* RESTRICT bucket2_p = &bucket2[c << 8];

      {
        fast_uint_t hi = index;
        if (sum < hi) {
          hi = sum;
        }
        libsais_unbwt_compute_histogram(&T[prev], (fast_sint_t)(hi - prev),
                                        bucket2_p);
      }

      {
        fast_uint_t lo = index + 1;
        if (prev > lo) {
          lo = prev;
        }
        libsais_unbwt_compute_histogram(&T[lo - 1], (fast_sint_t)(sum - lo),
                                        bucket2_p);
      }
    }
  }

  libsais_unbwt_transpose_bucket2(bucket2);
}

static void libsais_unbwt_calculate_fastbits(sa_uint_t* RESTRICT bucket2,
                                             uint16_t* RESTRICT fastbits,
                                             fast_uint_t lastc,
                                             fast_uint_t shift) {
  fast_uint_t v, w, sum, c, d;
  for (v = 0, w = 0, sum = 1, c = 0; c < ALPHABET_SIZE; ++c) {
    if (c == lastc) {
      sum += 1;
    }

    for (d = 0; d < ALPHABET_SIZE; ++d, ++w) {
      fast_uint_t prev = sum;
      sum += bucket2[w];
      bucket2[w] = (sa_uint_t)prev;
      if (prev != sum) {
        for (; v <= ((sum - 1) >> shift); ++v) {
          fastbits[v] = (uint16_t)w;
        }
      }
    }
  }
}

static void libsais_unbwt_calculate_biPSI(
    const uint8_t* RESTRICT T, sa_uint_t* RESTRICT P,
    sa_uint_t* RESTRICT bucket1, sa_uint_t* RESTRICT bucket2, fast_uint_t index,
    fast_sint_t omp_block_start, fast_sint_t omp_block_end) {
  {
    fast_sint_t i = omp_block_start, j = (fast_sint_t)index;
    if (omp_block_end < j) {
      j = omp_block_end;
    }
    for (; i < j; ++i) {
      fast_uint_t c = T[i];
      fast_uint_t p = bucket1[c]++;
      fast_sint_t t = (fast_sint_t)(index - p);

      if (t != 0) {
        fast_uint_t w =
            (((fast_uint_t)
                  T[p + (fast_uint_t)(t >> ((sizeof(fast_sint_t) * 8) - 1))])
             << 8) +
            c;
        P[bucket2[w]++] = (sa_uint_t)i;
      }
    }
  }

  {
    fast_sint_t i = (fast_sint_t)index, j = omp_block_end;
    if (omp_block_start > i) {
      i = omp_block_start;
    }
    for (i += 1; i <= j; ++i) {
      fast_uint_t c = T[i - 1];
      fast_uint_t p = bucket1[c]++;
      fast_sint_t t = (fast_sint_t)(index - p);

      if (t != 0) {
        fast_uint_t w =
            (((fast_uint_t)
                  T[p + (fast_uint_t)(t >> ((sizeof(fast_sint_t) * 8) - 1))])
             << 8) +
            c;
        P[bucket2[w]++] = (sa_uint_t)i;
      }
    }
  }
}

static void libsais_unbwt_init_single(const uint8_t* RESTRICT T,
                                      sa_uint_t* RESTRICT P, sa_sint_t n,
                                      const sa_sint_t* freq,
                                      const sa_uint_t* RESTRICT I,
                                      sa_uint_t* RESTRICT bucket2,
                                      uint16_t* RESTRICT fastbits) {
  sa_uint_t bucket1[ALPHABET_SIZE];

  fast_uint_t index = I[0];
  fast_uint_t lastc = T[0];
  fast_uint_t shift = 0;
  while ((n >> shift) > ((sa_sint_t)1 << UNBWT_FASTBITS)) {
    shift++;
  }

  if (freq != NULL) {
    memcpy(bucket1, freq, ALPHABET_SIZE * sizeof(sa_uint_t));
  } else {
    memset(bucket1, 0, ALPHABET_SIZE * sizeof(sa_uint_t));
    libsais_unbwt_compute_histogram(T, n, bucket1);
  }

  memset(bucket2, 0, ALPHABET_SIZE * ALPHABET_SIZE * sizeof(sa_uint_t));
  libsais_unbwt_compute_bigram_histogram_single(T, bucket1, bucket2, index);

  libsais_unbwt_calculate_fastbits(bucket2, fastbits, lastc, shift);
  libsais_unbwt_calculate_biPSI(T, P, bucket1, bucket2, index, 0, n);
}

#if defined(LIBSAIS_OPENMP)

static void libsais_unbwt_compute_bigram_histogram_parallel(
    const uint8_t* RESTRICT T, fast_uint_t index, sa_uint_t* RESTRICT bucket1,
    sa_uint_t* RESTRICT bucket2, fast_sint_t omp_block_start,
    fast_sint_t omp_block_size) {
  fast_sint_t i;
  for (i = omp_block_start; i < omp_block_start + omp_block_size; ++i) {
    fast_uint_t c = T[i];
    fast_uint_t p = bucket1[c]++;
    fast_sint_t t = (fast_sint_t)(index - p);

    if (t != 0) {
      fast_uint_t w =
          (((fast_uint_t)
                T[p + (fast_uint_t)(t >> ((sizeof(fast_sint_t) * 8) - 1))])
           << 8) +
          c;
      bucket2[w]++;
    }
  }
}

static void libsais_unbwt_init_parallel(
    const uint8_t* RESTRICT T, sa_uint_t* RESTRICT P, sa_sint_t n,
    const sa_sint_t* freq, const sa_uint_t* RESTRICT I,
    sa_uint_t* RESTRICT bucket2, uint16_t* RESTRICT fastbits,
    sa_uint_t* RESTRICT buckets, sa_sint_t threads) {
  sa_uint_t bucket1[ALPHABET_SIZE];

  fast_uint_t index = I[0];
  fast_uint_t lastc = T[0];
  fast_uint_t shift = 0;
  while ((n >> shift) > ((sa_sint_t)1 << UNBWT_FASTBITS)) {
    shift++;
  }

  memset(bucket1, 0, ALPHABET_SIZE * sizeof(sa_uint_t));
  memset(bucket2, 0, ALPHABET_SIZE * ALPHABET_SIZE * sizeof(sa_uint_t));

#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
  {
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();

    if (omp_num_threads == 1) {
      libsais_unbwt_init_single(T, P, n, freq, I, bucket2, fastbits);
    } else {
      sa_uint_t* RESTRICT bucket1_local =
          buckets +
          omp_thread_num * (ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE));
      sa_uint_t* RESTRICT bucket2_local = bucket1_local + ALPHABET_SIZE;

      fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
      fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
      fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                       ? omp_block_stride
                                       : n - omp_block_start;

      {
        memset(bucket1_local, 0, ALPHABET_SIZE * sizeof(sa_uint_t));
        libsais_unbwt_compute_histogram(T + omp_block_start, omp_block_size,
                                        bucket1_local);
      }

#pragma omp barrier

#pragma omp master
      {
        {
          sa_uint_t* RESTRICT bucket1_temp = buckets;

          fast_sint_t t;
          for (t = 0; t < omp_num_threads; ++t,
              bucket1_temp += ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE)) {
            fast_sint_t c;
            for (c = 0; c < ALPHABET_SIZE; c += 1) {
              sa_uint_t A = bucket1[c], B = bucket1_temp[c];
              bucket1[c] = A + B;
              bucket1_temp[c] = A;
            }
          }
        }

        {
          fast_uint_t sum, c;
          for (sum = 1, c = 0; c < ALPHABET_SIZE; ++c) {
            fast_uint_t prev = sum;
            sum += bucket1[c];
            bucket1[c] = (sa_uint_t)prev;
          }
        }
      }

#pragma omp barrier

      {
        fast_sint_t c;
        for (c = 0; c < ALPHABET_SIZE; c += 1) {
          sa_uint_t A = bucket1[c], B = bucket1_local[c];
          bucket1_local[c] = A + B;
        }

        memset(bucket2_local, 0,
               ALPHABET_SIZE * ALPHABET_SIZE * sizeof(sa_uint_t));
        libsais_unbwt_compute_bigram_histogram_parallel(
            T, index, bucket1_local, bucket2_local, omp_block_start,
            omp_block_size);
      }

#pragma omp barrier

      {
        fast_sint_t omp_bucket2_stride =
            ((ALPHABET_SIZE * ALPHABET_SIZE) / omp_num_threads) & (-16);
        fast_sint_t omp_bucket2_start = omp_thread_num * omp_bucket2_stride;
        fast_sint_t omp_bucket2_size =
            omp_thread_num < omp_num_threads - 1
                ? omp_bucket2_stride
                : (ALPHABET_SIZE * ALPHABET_SIZE) - omp_bucket2_start;

        sa_uint_t* RESTRICT bucket2_temp = buckets + ALPHABET_SIZE;

        fast_sint_t t;
        for (t = 0; t < omp_num_threads; ++t,
            bucket2_temp += ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE)) {
          fast_sint_t c;
          for (c = omp_bucket2_start; c < omp_bucket2_start + omp_bucket2_size;
               c += 1) {
            sa_uint_t A = bucket2[c], B = bucket2_temp[c];
            bucket2[c] = A + B;
            bucket2_temp[c] = A;
          }
        }
      }

#pragma omp barrier

#pragma omp master
      {
        libsais_unbwt_calculate_fastbits(bucket2, fastbits, lastc, shift);

        {
          fast_sint_t t;
          for (t = omp_num_threads - 1; t >= 1; --t) {
            sa_uint_t* RESTRICT dst_bucket1 =
                buckets + t * (ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE));
            sa_uint_t* RESTRICT src_bucket1 =
                dst_bucket1 - (ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE));

            memcpy(dst_bucket1, src_bucket1, ALPHABET_SIZE * sizeof(sa_uint_t));
          }

          memcpy(buckets, bucket1, ALPHABET_SIZE * sizeof(sa_uint_t));
        }
      }

#pragma omp barrier

      {
        fast_sint_t c;
        for (c = 0; c < ALPHABET_SIZE * ALPHABET_SIZE; c += 1) {
          sa_uint_t A = bucket2[c], B = bucket2_local[c];
          bucket2_local[c] = A + B;
        }

        libsais_unbwt_calculate_biPSI(T, P, bucket1_local, bucket2_local, index,
                                      omp_block_start,
                                      omp_block_start + omp_block_size);
      }

#pragma omp barrier

#pragma omp master
      {
        memcpy(bucket2,
               buckets + ALPHABET_SIZE +
                   (omp_num_threads - 1) *
                       (ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE)),
               ALPHABET_SIZE * ALPHABET_SIZE * sizeof(sa_uint_t));
      }
    }
  }
}

#endif

static void libsais_unbwt_decode_1(uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                   sa_uint_t* RESTRICT bucket2,
                                   uint16_t* RESTRICT fastbits,
                                   fast_uint_t shift, fast_uint_t* i0,
                                   fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;

  fast_uint_t i, p0 = *i0;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
  }

  *i0 = p0;
}

static void libsais_unbwt_decode_2(uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                   sa_uint_t* RESTRICT bucket2,
                                   uint16_t* RESTRICT fastbits,
                                   fast_uint_t shift, fast_uint_t r,
                                   fast_uint_t* i0, fast_uint_t* i1,
                                   fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
  }

  *i0 = p0;
  *i1 = p1;
}

static void libsais_unbwt_decode_3(uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                   sa_uint_t* RESTRICT bucket2,
                                   uint16_t* RESTRICT fastbits,
                                   fast_uint_t shift, fast_uint_t r,
                                   fast_uint_t* i0, fast_uint_t* i1,
                                   fast_uint_t* i2, fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);
  uint16_t* RESTRICT U2 = (uint16_t*)(void*)(((uint8_t*)U1) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1, p2 = *i2;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
    uint16_t c2 = fastbits[p2 >> shift];
    if (bucket2[c2] <= p2) {
      do {
        c2++;
      } while (bucket2[c2] <= p2);
    }
    p2 = P[p2];
    U2[i] = libsais_bswap16(c2);
  }

  *i0 = p0;
  *i1 = p1;
  *i2 = p2;
}

static void libsais_unbwt_decode_4(uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                   sa_uint_t* RESTRICT bucket2,
                                   uint16_t* RESTRICT fastbits,
                                   fast_uint_t shift, fast_uint_t r,
                                   fast_uint_t* i0, fast_uint_t* i1,
                                   fast_uint_t* i2, fast_uint_t* i3,
                                   fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);
  uint16_t* RESTRICT U2 = (uint16_t*)(void*)(((uint8_t*)U1) + r);
  uint16_t* RESTRICT U3 = (uint16_t*)(void*)(((uint8_t*)U2) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1, p2 = *i2, p3 = *i3;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
    uint16_t c2 = fastbits[p2 >> shift];
    if (bucket2[c2] <= p2) {
      do {
        c2++;
      } while (bucket2[c2] <= p2);
    }
    p2 = P[p2];
    U2[i] = libsais_bswap16(c2);
    uint16_t c3 = fastbits[p3 >> shift];
    if (bucket2[c3] <= p3) {
      do {
        c3++;
      } while (bucket2[c3] <= p3);
    }
    p3 = P[p3];
    U3[i] = libsais_bswap16(c3);
  }

  *i0 = p0;
  *i1 = p1;
  *i2 = p2;
  *i3 = p3;
}

static void libsais_unbwt_decode_5(uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                   sa_uint_t* RESTRICT bucket2,
                                   uint16_t* RESTRICT fastbits,
                                   fast_uint_t shift, fast_uint_t r,
                                   fast_uint_t* i0, fast_uint_t* i1,
                                   fast_uint_t* i2, fast_uint_t* i3,
                                   fast_uint_t* i4, fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);
  uint16_t* RESTRICT U2 = (uint16_t*)(void*)(((uint8_t*)U1) + r);
  uint16_t* RESTRICT U3 = (uint16_t*)(void*)(((uint8_t*)U2) + r);
  uint16_t* RESTRICT U4 = (uint16_t*)(void*)(((uint8_t*)U3) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1, p2 = *i2, p3 = *i3, p4 = *i4;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
    uint16_t c2 = fastbits[p2 >> shift];
    if (bucket2[c2] <= p2) {
      do {
        c2++;
      } while (bucket2[c2] <= p2);
    }
    p2 = P[p2];
    U2[i] = libsais_bswap16(c2);
    uint16_t c3 = fastbits[p3 >> shift];
    if (bucket2[c3] <= p3) {
      do {
        c3++;
      } while (bucket2[c3] <= p3);
    }
    p3 = P[p3];
    U3[i] = libsais_bswap16(c3);
    uint16_t c4 = fastbits[p4 >> shift];
    if (bucket2[c4] <= p4) {
      do {
        c4++;
      } while (bucket2[c4] <= p4);
    }
    p4 = P[p4];
    U4[i] = libsais_bswap16(c4);
  }

  *i0 = p0;
  *i1 = p1;
  *i2 = p2;
  *i3 = p3;
  *i4 = p4;
}

static void libsais_unbwt_decode_6(
    uint8_t* RESTRICT U, sa_uint_t* RESTRICT P, sa_uint_t* RESTRICT bucket2,
    uint16_t* RESTRICT fastbits, fast_uint_t shift, fast_uint_t r,
    fast_uint_t* i0, fast_uint_t* i1, fast_uint_t* i2, fast_uint_t* i3,
    fast_uint_t* i4, fast_uint_t* i5, fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);
  uint16_t* RESTRICT U2 = (uint16_t*)(void*)(((uint8_t*)U1) + r);
  uint16_t* RESTRICT U3 = (uint16_t*)(void*)(((uint8_t*)U2) + r);
  uint16_t* RESTRICT U4 = (uint16_t*)(void*)(((uint8_t*)U3) + r);
  uint16_t* RESTRICT U5 = (uint16_t*)(void*)(((uint8_t*)U4) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1, p2 = *i2, p3 = *i3, p4 = *i4, p5 = *i5;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
    uint16_t c2 = fastbits[p2 >> shift];
    if (bucket2[c2] <= p2) {
      do {
        c2++;
      } while (bucket2[c2] <= p2);
    }
    p2 = P[p2];
    U2[i] = libsais_bswap16(c2);
    uint16_t c3 = fastbits[p3 >> shift];
    if (bucket2[c3] <= p3) {
      do {
        c3++;
      } while (bucket2[c3] <= p3);
    }
    p3 = P[p3];
    U3[i] = libsais_bswap16(c3);
    uint16_t c4 = fastbits[p4 >> shift];
    if (bucket2[c4] <= p4) {
      do {
        c4++;
      } while (bucket2[c4] <= p4);
    }
    p4 = P[p4];
    U4[i] = libsais_bswap16(c4);
    uint16_t c5 = fastbits[p5 >> shift];
    if (bucket2[c5] <= p5) {
      do {
        c5++;
      } while (bucket2[c5] <= p5);
    }
    p5 = P[p5];
    U5[i] = libsais_bswap16(c5);
  }

  *i0 = p0;
  *i1 = p1;
  *i2 = p2;
  *i3 = p3;
  *i4 = p4;
  *i5 = p5;
}

static void libsais_unbwt_decode_7(
    uint8_t* RESTRICT U, sa_uint_t* RESTRICT P, sa_uint_t* RESTRICT bucket2,
    uint16_t* RESTRICT fastbits, fast_uint_t shift, fast_uint_t r,
    fast_uint_t* i0, fast_uint_t* i1, fast_uint_t* i2, fast_uint_t* i3,
    fast_uint_t* i4, fast_uint_t* i5, fast_uint_t* i6, fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);
  uint16_t* RESTRICT U2 = (uint16_t*)(void*)(((uint8_t*)U1) + r);
  uint16_t* RESTRICT U3 = (uint16_t*)(void*)(((uint8_t*)U2) + r);
  uint16_t* RESTRICT U4 = (uint16_t*)(void*)(((uint8_t*)U3) + r);
  uint16_t* RESTRICT U5 = (uint16_t*)(void*)(((uint8_t*)U4) + r);
  uint16_t* RESTRICT U6 = (uint16_t*)(void*)(((uint8_t*)U5) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1, p2 = *i2, p3 = *i3, p4 = *i4, p5 = *i5,
                 p6 = *i6;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
    uint16_t c2 = fastbits[p2 >> shift];
    if (bucket2[c2] <= p2) {
      do {
        c2++;
      } while (bucket2[c2] <= p2);
    }
    p2 = P[p2];
    U2[i] = libsais_bswap16(c2);
    uint16_t c3 = fastbits[p3 >> shift];
    if (bucket2[c3] <= p3) {
      do {
        c3++;
      } while (bucket2[c3] <= p3);
    }
    p3 = P[p3];
    U3[i] = libsais_bswap16(c3);
    uint16_t c4 = fastbits[p4 >> shift];
    if (bucket2[c4] <= p4) {
      do {
        c4++;
      } while (bucket2[c4] <= p4);
    }
    p4 = P[p4];
    U4[i] = libsais_bswap16(c4);
    uint16_t c5 = fastbits[p5 >> shift];
    if (bucket2[c5] <= p5) {
      do {
        c5++;
      } while (bucket2[c5] <= p5);
    }
    p5 = P[p5];
    U5[i] = libsais_bswap16(c5);
    uint16_t c6 = fastbits[p6 >> shift];
    if (bucket2[c6] <= p6) {
      do {
        c6++;
      } while (bucket2[c6] <= p6);
    }
    p6 = P[p6];
    U6[i] = libsais_bswap16(c6);
  }

  *i0 = p0;
  *i1 = p1;
  *i2 = p2;
  *i3 = p3;
  *i4 = p4;
  *i5 = p5;
  *i6 = p6;
}

static void libsais_unbwt_decode_8(
    uint8_t* RESTRICT U, sa_uint_t* RESTRICT P, sa_uint_t* RESTRICT bucket2,
    uint16_t* RESTRICT fastbits, fast_uint_t shift, fast_uint_t r,
    fast_uint_t* i0, fast_uint_t* i1, fast_uint_t* i2, fast_uint_t* i3,
    fast_uint_t* i4, fast_uint_t* i5, fast_uint_t* i6, fast_uint_t* i7,
    fast_uint_t k) {
  uint16_t* RESTRICT U0 = (uint16_t*)(void*)U;
  uint16_t* RESTRICT U1 = (uint16_t*)(void*)(((uint8_t*)U0) + r);
  uint16_t* RESTRICT U2 = (uint16_t*)(void*)(((uint8_t*)U1) + r);
  uint16_t* RESTRICT U3 = (uint16_t*)(void*)(((uint8_t*)U2) + r);
  uint16_t* RESTRICT U4 = (uint16_t*)(void*)(((uint8_t*)U3) + r);
  uint16_t* RESTRICT U5 = (uint16_t*)(void*)(((uint8_t*)U4) + r);
  uint16_t* RESTRICT U6 = (uint16_t*)(void*)(((uint8_t*)U5) + r);
  uint16_t* RESTRICT U7 = (uint16_t*)(void*)(((uint8_t*)U6) + r);

  fast_uint_t i, p0 = *i0, p1 = *i1, p2 = *i2, p3 = *i3, p4 = *i4, p5 = *i5,
                 p6 = *i6, p7 = *i7;

  for (i = 0; i != k; ++i) {
    uint16_t c0 = fastbits[p0 >> shift];
    if (bucket2[c0] <= p0) {
      do {
        c0++;
      } while (bucket2[c0] <= p0);
    }
    p0 = P[p0];
    U0[i] = libsais_bswap16(c0);
    uint16_t c1 = fastbits[p1 >> shift];
    if (bucket2[c1] <= p1) {
      do {
        c1++;
      } while (bucket2[c1] <= p1);
    }
    p1 = P[p1];
    U1[i] = libsais_bswap16(c1);
    uint16_t c2 = fastbits[p2 >> shift];
    if (bucket2[c2] <= p2) {
      do {
        c2++;
      } while (bucket2[c2] <= p2);
    }
    p2 = P[p2];
    U2[i] = libsais_bswap16(c2);
    uint16_t c3 = fastbits[p3 >> shift];
    if (bucket2[c3] <= p3) {
      do {
        c3++;
      } while (bucket2[c3] <= p3);
    }
    p3 = P[p3];
    U3[i] = libsais_bswap16(c3);
    uint16_t c4 = fastbits[p4 >> shift];
    if (bucket2[c4] <= p4) {
      do {
        c4++;
      } while (bucket2[c4] <= p4);
    }
    p4 = P[p4];
    U4[i] = libsais_bswap16(c4);
    uint16_t c5 = fastbits[p5 >> shift];
    if (bucket2[c5] <= p5) {
      do {
        c5++;
      } while (bucket2[c5] <= p5);
    }
    p5 = P[p5];
    U5[i] = libsais_bswap16(c5);
    uint16_t c6 = fastbits[p6 >> shift];
    if (bucket2[c6] <= p6) {
      do {
        c6++;
      } while (bucket2[c6] <= p6);
    }
    p6 = P[p6];
    U6[i] = libsais_bswap16(c6);
    uint16_t c7 = fastbits[p7 >> shift];
    if (bucket2[c7] <= p7) {
      do {
        c7++;
      } while (bucket2[c7] <= p7);
    }
    p7 = P[p7];
    U7[i] = libsais_bswap16(c7);
  }

  *i0 = p0;
  *i1 = p1;
  *i2 = p2;
  *i3 = p3;
  *i4 = p4;
  *i5 = p5;
  *i6 = p6;
  *i7 = p7;
}

static void libsais_unbwt_decode(uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                 sa_sint_t n, sa_sint_t r,
                                 const sa_uint_t* RESTRICT I,
                                 sa_uint_t* RESTRICT bucket2,
                                 uint16_t* RESTRICT fastbits,
                                 fast_sint_t blocks, fast_uint_t remainder) {
  fast_uint_t shift = 0;
  while ((n >> shift) > ((sa_sint_t)1 << UNBWT_FASTBITS)) {
    shift++;
  }
  fast_uint_t offset = 0;

  while (blocks > 8) {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2], i3 = I[3], i4 = I[4],
                i5 = I[5], i6 = I[6], i7 = I[7];
    libsais_unbwt_decode_8(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, &i3, &i4, &i5, &i6,
                           &i7, (fast_uint_t)r >> 1);
    I += 8;
    blocks -= 8;
    offset += 8 * (fast_uint_t)r;
  }

  if (blocks == 1) {
    fast_uint_t i0 = I[0];
    libsais_unbwt_decode_1(U + offset, P, bucket2, fastbits, shift, &i0,
                           remainder >> 1);
  } else if (blocks == 2) {
    fast_uint_t i0 = I[0], i1 = I[1];
    libsais_unbwt_decode_2(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, remainder >> 1);
    libsais_unbwt_decode_1(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, &i0,
                           ((fast_uint_t)r >> 1) - (remainder >> 1));
  } else if (blocks == 3) {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2];
    libsais_unbwt_decode_3(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, remainder >> 1);
    libsais_unbwt_decode_2(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, (fast_uint_t)r, &i0, &i1,
                           ((fast_uint_t)r >> 1) - (remainder >> 1));
  } else if (blocks == 4) {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2], i3 = I[3];
    libsais_unbwt_decode_4(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, &i3, remainder >> 1);
    libsais_unbwt_decode_3(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, (fast_uint_t)r, &i0, &i1, &i2,
                           ((fast_uint_t)r >> 1) - (remainder >> 1));
  } else if (blocks == 5) {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2], i3 = I[3], i4 = I[4];
    libsais_unbwt_decode_5(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, &i3, &i4,
                           remainder >> 1);
    libsais_unbwt_decode_4(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, (fast_uint_t)r, &i0, &i1, &i2, &i3,
                           ((fast_uint_t)r >> 1) - (remainder >> 1));
  } else if (blocks == 6) {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2], i3 = I[3], i4 = I[4],
                i5 = I[5];
    libsais_unbwt_decode_6(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, &i3, &i4, &i5,
                           remainder >> 1);
    libsais_unbwt_decode_5(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, (fast_uint_t)r, &i0, &i1, &i2, &i3,
                           &i4, ((fast_uint_t)r >> 1) - (remainder >> 1));
  } else if (blocks == 7) {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2], i3 = I[3], i4 = I[4],
                i5 = I[5], i6 = I[6];
    libsais_unbwt_decode_7(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, &i3, &i4, &i5, &i6,
                           remainder >> 1);
    libsais_unbwt_decode_6(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, (fast_uint_t)r, &i0, &i1, &i2, &i3,
                           &i4, &i5, ((fast_uint_t)r >> 1) - (remainder >> 1));
  } else {
    fast_uint_t i0 = I[0], i1 = I[1], i2 = I[2], i3 = I[3], i4 = I[4],
                i5 = I[5], i6 = I[6], i7 = I[7];
    libsais_unbwt_decode_8(U + offset, P, bucket2, fastbits, shift,
                           (fast_uint_t)r, &i0, &i1, &i2, &i3, &i4, &i5, &i6,
                           &i7, remainder >> 1);
    libsais_unbwt_decode_7(U + offset + 2 * (remainder >> 1), P, bucket2,
                           fastbits, shift, (fast_uint_t)r, &i0, &i1, &i2, &i3,
                           &i4, &i5, &i6,
                           ((fast_uint_t)r >> 1) - (remainder >> 1));
  }
}

static void libsais_unbwt_decode_omp(const uint8_t* RESTRICT T,
                                     uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                     sa_sint_t n, sa_sint_t r,
                                     const sa_uint_t* RESTRICT I,
                                     sa_uint_t* RESTRICT bucket2,
                                     uint16_t* RESTRICT fastbits,
                                     sa_sint_t threads) {
  fast_uint_t lastc = T[0];
  fast_sint_t blocks = 1 + (((fast_sint_t)n - 1) / (fast_sint_t)r);
  fast_uint_t remainder =
      (fast_uint_t)n - ((fast_uint_t)r * ((fast_uint_t)blocks - 1));

#if defined(LIBSAIS_OPENMP)
  fast_sint_t max_threads = blocks < threads ? blocks : threads;
#pragma omp parallel num_threads(max_threads) if (max_threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif

    fast_sint_t omp_block_stride = blocks / omp_num_threads;
    fast_sint_t omp_block_remainder = blocks % omp_num_threads;
    fast_sint_t omp_block_size =
        omp_block_stride + (omp_thread_num < omp_block_remainder);
    fast_sint_t omp_block_start =
        omp_block_stride * omp_thread_num +
        (omp_thread_num < omp_block_remainder ? omp_thread_num
                                              : omp_block_remainder);

    libsais_unbwt_decode(
        U + r * omp_block_start, P, n, r, I + omp_block_start, bucket2,
        fastbits, omp_block_size,
        omp_thread_num < omp_num_threads - 1 ? (fast_uint_t)r : remainder);
  }

  U[n - 1] = (uint8_t)lastc;
}

static sa_sint_t libsais_unbwt_core(const uint8_t* RESTRICT T,
                                    uint8_t* RESTRICT U, sa_uint_t* RESTRICT P,
                                    sa_sint_t n, const sa_sint_t* freq,
                                    sa_sint_t r, const sa_uint_t* RESTRICT I,
                                    sa_uint_t* RESTRICT bucket2,
                                    uint16_t* RESTRICT fastbits,
                                    sa_uint_t* RESTRICT buckets,
                                    sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
  if (threads > 1 && n >= 262144) {
    libsais_unbwt_init_parallel(T, P, n, freq, I, bucket2, fastbits, buckets,
                                threads);
  } else
#else
  UNUSED(buckets);
#endif
  {
    libsais_unbwt_init_single(T, P, n, freq, I, bucket2, fastbits);
  }

  libsais_unbwt_decode_omp(T, U, P, n, r, I, bucket2, fastbits, threads);
  return 0;
}

static sa_sint_t libsais_unbwt_main(const uint8_t* T, uint8_t* U, sa_uint_t* P,
                                    sa_sint_t n, const sa_sint_t* freq,
                                    sa_sint_t r, const sa_uint_t* I,
                                    sa_sint_t threads) {
  fast_uint_t shift = 0;
  while ((n >> shift) > ((sa_sint_t)1 << UNBWT_FASTBITS)) {
    shift++;
  }

  sa_uint_t* RESTRICT bucket2 = (sa_uint_t*)libsais_alloc_aligned(
      ALPHABET_SIZE * ALPHABET_SIZE * sizeof(sa_uint_t), 4096);
  uint16_t* RESTRICT fastbits = (uint16_t*)libsais_alloc_aligned(
      ((size_t)1 + (size_t)(n >> shift)) * sizeof(uint16_t), 4096);
  sa_uint_t* RESTRICT buckets =
      threads > 1 && n >= 262144
          ? (sa_uint_t*)libsais_alloc_aligned(
                (size_t)threads *
                    (ALPHABET_SIZE + (ALPHABET_SIZE * ALPHABET_SIZE)) *
                    sizeof(sa_uint_t),
                4096)
          : NULL;

  sa_sint_t index = bucket2 != NULL && fastbits != NULL &&
                            (buckets != NULL || threads == 1 || n < 262144)
                        ? libsais_unbwt_core(T, U, P, n, freq, r, I, bucket2,
                                             fastbits, buckets, threads)
                        : -2;

  libsais_free_aligned(buckets);
  libsais_free_aligned(fastbits);
  libsais_free_aligned(bucket2);

  return index;
}

static sa_sint_t libsais_unbwt_main_ctx(const LIBSAIS_UNBWT_CONTEXT* ctx,
                                        const uint8_t* T, uint8_t* U,
                                        sa_uint_t* P, sa_sint_t n,
                                        const sa_sint_t* freq, sa_sint_t r,
                                        const sa_uint_t* I) {
  return ctx != NULL && ctx->bucket2 != NULL && ctx->fastbits != NULL &&
                 (ctx->buckets != NULL || ctx->threads == 1)
             ? libsais_unbwt_core(T, U, P, n, freq, r, I, ctx->bucket2,
                                  ctx->fastbits, ctx->buckets,
                                  (sa_sint_t)ctx->threads)
             : -2;
}

void* libsais_unbwt_create_ctx(void) {
  return (void*)libsais_unbwt_create_ctx_main(1);
}

void libsais_unbwt_free_ctx(void* ctx) {
  libsais_unbwt_free_ctx_main((LIBSAIS_UNBWT_CONTEXT*)ctx);
}

int32_t libsais_unbwt(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                      const int32_t* freq, int32_t i) {
  return libsais_unbwt_aux(T, U, A, n, freq, n, &i);
}

int32_t libsais_unbwt_ctx(const void* ctx, const uint8_t* T, uint8_t* U,
                          int32_t* A, int32_t n, const int32_t* freq,
                          int32_t i) {
  return libsais_unbwt_aux_ctx(ctx, T, U, A, n, freq, n, &i);
}

int32_t libsais_unbwt_aux(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                          const int32_t* freq, int32_t r, const int32_t* I) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) ||
      ((r != n) && ((r < 2) || ((r & (r - 1)) != 0))) || (I == NULL)) {
    return -1;
  } else if (n <= 1) {
    if (I[0] != n) {
      return -1;
    }
    if (n == 1) {
      U[0] = T[0];
    }
    return 0;
  }

  fast_sint_t t;
  for (t = 0; t <= (n - 1) / r; ++t) {
    if (I[t] <= 0 || I[t] > n) {
      return -1;
    }
  }

  return libsais_unbwt_main(T, U, (sa_uint_t*)A, n, freq, r,
                            (const sa_uint_t*)I, 1);
}

int32_t libsais_unbwt_aux_ctx(const void* ctx, const uint8_t* T, uint8_t* U,
                              int32_t* A, int32_t n, const int32_t* freq,
                              int32_t r, const int32_t* I) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) ||
      ((r != n) && ((r < 2) || ((r & (r - 1)) != 0))) || (I == NULL)) {
    return -1;
  } else if (n <= 1) {
    if (I[0] != n) {
      return -1;
    }
    if (n == 1) {
      U[0] = T[0];
    }
    return 0;
  }

  fast_sint_t t;
  for (t = 0; t <= (n - 1) / r; ++t) {
    if (I[t] <= 0 || I[t] > n) {
      return -1;
    }
  }

  return libsais_unbwt_main_ctx((const LIBSAIS_UNBWT_CONTEXT*)ctx, T, U,
                                (sa_uint_t*)A, n, freq, r, (const sa_uint_t*)I);
}

#if defined(LIBSAIS_OPENMP)

void* libsais_unbwt_create_ctx_omp(int32_t threads) {
  if (threads < 0) {
    return NULL;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  return (void*)libsais_unbwt_create_ctx_main(threads);
}

int32_t libsais_unbwt_omp(const uint8_t* T, uint8_t* U, int32_t* A, int32_t n,
                          const int32_t* freq, int32_t i, int32_t threads) {
  return libsais_unbwt_aux_omp(T, U, A, n, freq, n, &i, threads);
}

int32_t libsais_unbwt_aux_omp(const uint8_t* T, uint8_t* U, int32_t* A,
                              int32_t n, const int32_t* freq, int32_t r,
                              const int32_t* I, int32_t threads) {
  if ((T == NULL) || (U == NULL) || (A == NULL) || (n < 0) ||
      ((r != n) && ((r < 2) || ((r & (r - 1)) != 0))) || (I == NULL) ||
      (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (I[0] != n) {
      return -1;
    }
    if (n == 1) {
      U[0] = T[0];
    }
    return 0;
  }

  fast_sint_t t;
  for (t = 0; t <= (n - 1) / r; ++t) {
    if (I[t] <= 0 || I[t] > n) {
      return -1;
    }
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  return libsais_unbwt_main(T, U, (sa_uint_t*)A, n, freq, r,
                            (const sa_uint_t*)I, threads);
}

#endif

static void libsais_compute_phi(const sa_sint_t* RESTRICT SA,
                                sa_sint_t* RESTRICT PLCP, sa_sint_t n,
                                fast_sint_t omp_block_start,
                                fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  sa_sint_t k = omp_block_start > 0 ? SA[omp_block_start - 1] : n;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);

    libsais_prefetchw(&PLCP[SA[i + prefetch_distance + 0]]);
    libsais_prefetchw(&PLCP[SA[i + prefetch_distance + 1]]);

    PLCP[SA[i + 0]] = k;
    k = SA[i + 0];
    PLCP[SA[i + 1]] = k;
    k = SA[i + 1];

    libsais_prefetchw(&PLCP[SA[i + prefetch_distance + 2]]);
    libsais_prefetchw(&PLCP[SA[i + prefetch_distance + 3]]);

    PLCP[SA[i + 2]] = k;
    k = SA[i + 2];
    PLCP[SA[i + 3]] = k;
    k = SA[i + 3];
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    PLCP[SA[i]] = k;
    k = SA[i];
  }
}

static void libsais_compute_phi_omp(const sa_sint_t* RESTRICT SA,
                                    sa_sint_t* RESTRICT PLCP, sa_sint_t n,
                                    sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    libsais_compute_phi(SA, PLCP, n, omp_block_start, omp_block_size);
  }
}

static void libsais_compute_plcp(const uint8_t* RESTRICT T,
                                 sa_sint_t* RESTRICT PLCP, fast_sint_t n,
                                 fast_sint_t omp_block_start,
                                 fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, l = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance;
       i < j; i += 1) {
    libsais_prefetchw(&PLCP[i + 2 * prefetch_distance]);
    libsais_prefetchr(&T[PLCP[i + prefetch_distance] + l]);

    fast_sint_t k = PLCP[i], m = n - (i > k ? i : k);
    while (l < m && T[i + l] == T[k + l]) {
      l++;
    }

    PLCP[i] = (sa_sint_t)l;
    l -= (l != 0);
  }

  for (j += prefetch_distance; i < j; i += 1) {
    fast_sint_t k = PLCP[i], m = n - (i > k ? i : k);
    while (l < m && T[i + l] == T[k + l]) {
      l++;
    }

    PLCP[i] = (sa_sint_t)l;
    l -= (l != 0);
  }
}

static void libsais_compute_plcp_omp(const uint8_t* RESTRICT T,
                                     sa_sint_t* RESTRICT PLCP, sa_sint_t n,
                                     sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    libsais_compute_plcp(T, PLCP, n, omp_block_start, omp_block_size);
  }
}

static void libsais_compute_plcp_gsa(const uint8_t* RESTRICT T,
                                     sa_sint_t* RESTRICT PLCP,
                                     fast_sint_t omp_block_start,
                                     fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, l = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance;
       i < j; i += 1) {
    libsais_prefetchw(&PLCP[i + 2 * prefetch_distance]);
    libsais_prefetchr(&T[PLCP[i + prefetch_distance] + l]);

    fast_sint_t k = PLCP[i];
    while (T[i + l] > 0 && T[i + l] == T[k + l]) {
      l++;
    }

    PLCP[i] = (sa_sint_t)l;
    l -= (l != 0);
  }

  for (j += prefetch_distance; i < j; i += 1) {
    fast_sint_t k = PLCP[i];
    while (T[i + l] > 0 && T[i + l] == T[k + l]) {
      l++;
    }

    PLCP[i] = (sa_sint_t)l;
    l -= (l != 0);
  }
}

static void libsais_compute_plcp_gsa_omp(const uint8_t* RESTRICT T,
                                         sa_sint_t* RESTRICT PLCP, sa_sint_t n,
                                         sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    libsais_compute_plcp_gsa(T, PLCP, omp_block_start, omp_block_size);
  }
}

static void libsais_compute_plcp_int(const int32_t* RESTRICT T,
                                     sa_sint_t* RESTRICT PLCP, fast_sint_t n,
                                     fast_sint_t omp_block_start,
                                     fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j, l = 0;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance;
       i < j; i += 1) {
    libsais_prefetchw(&PLCP[i + 2 * prefetch_distance]);
    libsais_prefetchr(&T[PLCP[i + prefetch_distance] + l]);

    fast_sint_t k = PLCP[i], m = n - (i > k ? i : k);
    while (l < m && T[i + l] == T[k + l]) {
      l++;
    }

    PLCP[i] = (sa_sint_t)l;
    l -= (l != 0);
  }

  for (j += prefetch_distance; i < j; i += 1) {
    fast_sint_t k = PLCP[i], m = n - (i > k ? i : k);
    while (l < m && T[i + l] == T[k + l]) {
      l++;
    }

    PLCP[i] = (sa_sint_t)l;
    l -= (l != 0);
  }
}

static void libsais_compute_plcp_int_omp(const int32_t* RESTRICT T,
                                         sa_sint_t* RESTRICT PLCP, sa_sint_t n,
                                         sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    libsais_compute_plcp_int(T, PLCP, n, omp_block_start, omp_block_size);
  }
}

static void libsais_compute_lcp(const sa_sint_t* RESTRICT PLCP,
                                const sa_sint_t* RESTRICT SA,
                                sa_sint_t* RESTRICT LCP,
                                fast_sint_t omp_block_start,
                                fast_sint_t omp_block_size) {
  const fast_sint_t prefetch_distance = 64;

  fast_sint_t i, j;
  for (i = omp_block_start,
      j = omp_block_start + omp_block_size - prefetch_distance - 3;
       i < j; i += 4) {
    libsais_prefetchr(&SA[i + 2 * prefetch_distance]);
    libsais_prefetchw(&LCP[i + prefetch_distance]);

    libsais_prefetchr(&PLCP[SA[i + prefetch_distance + 0]]);
    libsais_prefetchr(&PLCP[SA[i + prefetch_distance + 1]]);

    LCP[i + 0] = PLCP[SA[i + 0]];
    LCP[i + 1] = PLCP[SA[i + 1]];

    libsais_prefetchr(&PLCP[SA[i + prefetch_distance + 2]]);
    libsais_prefetchr(&PLCP[SA[i + prefetch_distance + 3]]);

    LCP[i + 2] = PLCP[SA[i + 2]];
    LCP[i + 3] = PLCP[SA[i + 3]];
  }

  for (j += prefetch_distance + 3; i < j; i += 1) {
    LCP[i] = PLCP[SA[i]];
  }
}

static void libsais_compute_lcp_omp(const sa_sint_t* RESTRICT PLCP,
                                    const sa_sint_t* RESTRICT SA,
                                    sa_sint_t* RESTRICT LCP, sa_sint_t n,
                                    sa_sint_t threads) {
#if defined(LIBSAIS_OPENMP)
#pragma omp parallel num_threads(threads) if (threads > 1 && n >= 65536)
#endif
  {
#if defined(LIBSAIS_OPENMP)
    fast_sint_t omp_thread_num = omp_get_thread_num();
    fast_sint_t omp_num_threads = omp_get_num_threads();
#else
    UNUSED(threads);

    fast_sint_t omp_thread_num = 0;
    fast_sint_t omp_num_threads = 1;
#endif
    fast_sint_t omp_block_stride = (n / omp_num_threads) & (-16);
    fast_sint_t omp_block_start = omp_thread_num * omp_block_stride;
    fast_sint_t omp_block_size = omp_thread_num < omp_num_threads - 1
                                     ? omp_block_stride
                                     : n - omp_block_start;

    libsais_compute_lcp(PLCP, SA, LCP, omp_block_start, omp_block_size);
  }
}

int32_t libsais_plcp(const uint8_t* T, const int32_t* SA, int32_t* PLCP,
                     int32_t n) {
  if ((T == NULL) || (SA == NULL) || (PLCP == NULL) || (n < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      PLCP[0] = 0;
    }
    return 0;
  }

  libsais_compute_phi_omp(SA, PLCP, n, 1);
  libsais_compute_plcp_omp(T, PLCP, n, 1);

  return 0;
}

int32_t libsais_plcp_gsa(const uint8_t* T, const int32_t* SA, int32_t* PLCP,
                         int32_t n) {
  if ((T == NULL) || (SA == NULL) || (PLCP == NULL) || (n < 0) ||
      (n > 0 && T[n - 1] != 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      PLCP[0] = 0;
    }
    return 0;
  }

  libsais_compute_phi_omp(SA, PLCP, n, 1);
  libsais_compute_plcp_gsa_omp(T, PLCP, n, 1);

  return 0;
}

int32_t libsais_plcp_int(const int32_t* T, const int32_t* SA, int32_t* PLCP,
                         int32_t n) {
  if ((T == NULL) || (SA == NULL) || (PLCP == NULL) || (n < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      PLCP[0] = 0;
    }
    return 0;
  }

  libsais_compute_phi_omp(SA, PLCP, n, 1);
  libsais_compute_plcp_int_omp(T, PLCP, n, 1);

  return 0;
}

int32_t libsais_lcp(const int32_t* PLCP, const int32_t* SA, int32_t* LCP,
                    int32_t n) {
  if ((PLCP == NULL) || (SA == NULL) || (LCP == NULL) || (n < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      LCP[0] = PLCP[SA[0]];
    }
    return 0;
  }

  libsais_compute_lcp_omp(PLCP, SA, LCP, n, 1);

  return 0;
}

#if defined(LIBSAIS_OPENMP)

int32_t libsais_plcp_omp(const uint8_t* T, const int32_t* SA, int32_t* PLCP,
                         int32_t n, int32_t threads) {
  if ((T == NULL) || (SA == NULL) || (PLCP == NULL) || (n < 0) ||
      (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      PLCP[0] = 0;
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  libsais_compute_phi_omp(SA, PLCP, n, threads);
  libsais_compute_plcp_omp(T, PLCP, n, threads);

  return 0;
}

int32_t libsais_plcp_gsa_omp(const uint8_t* T, const int32_t* SA, int32_t* PLCP,
                             int32_t n, int32_t threads) {
  if ((T == NULL) || (SA == NULL) || (PLCP == NULL) || (n < 0) ||
      (n > 0 && T[n - 1] != 0) || (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      PLCP[0] = 0;
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  libsais_compute_phi_omp(SA, PLCP, n, threads);
  libsais_compute_plcp_gsa_omp(T, PLCP, n, threads);

  return 0;
}

int32_t libsais_plcp_int_omp(const int32_t* T, const int32_t* SA, int32_t* PLCP,
                             int32_t n, int32_t threads) {
  if ((T == NULL) || (SA == NULL) || (PLCP == NULL) || (n < 0) ||
      (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      PLCP[0] = 0;
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  libsais_compute_phi_omp(SA, PLCP, n, threads);
  libsais_compute_plcp_int_omp(T, PLCP, n, threads);

  return 0;
}

int32_t libsais_lcp_omp(const int32_t* PLCP, const int32_t* SA, int32_t* LCP,
                        int32_t n, int32_t threads) {
  if ((PLCP == NULL) || (SA == NULL) || (LCP == NULL) || (n < 0) ||
      (threads < 0)) {
    return -1;
  } else if (n <= 1) {
    if (n == 1) {
      LCP[0] = PLCP[SA[0]];
    }
    return 0;
  }

  threads =
      threads > 0 ? threads : (omp_get_max_threads() / omp_get_num_threads());
  threads = threads > 0 ? threads : 1;

  libsais_compute_lcp_omp(PLCP, SA, LCP, n, threads);

  return 0;
}

#endif

Coverage Report

Created: 2026-10-31 06:13