// Copyright 2011 Google Inc. All Rights Reserved.

//

// Use of this source code is governed by a BSD-style license

// that can be found in the COPYING file in the root of the source

// tree. An additional intellectual property rights grant can be found

// in the file PATENTS. All contributing project authors may

// be found in the AUTHORS file in the root of the source tree.

// -----------------------------------------------------------------------------

//

// CPU detection

//

// Author: Christian Duvivier (cduvivier@google.com)

#include "src/dsp/cpu.h"

#if defined(WEBP_HAVE_NEON_RTCD)

#include <stdio.h>

#include <string.h>

#endif

#if defined(WEBP_ANDROID_NEON)

#include <cpu-features.h>

#endif

#include <stddef.h>

#include "src/webp/types.h"

//------------------------------------------------------------------------------

// SSE2 detection.

//

// apple/darwin gcc-4.0.1 defines __PIC__, but not __pic__ with -fPIC.

#if (defined(__pic__) || defined(__PIC__)) && defined(__i386__)

static WEBP_INLINE void GetCPUInfo(int cpu_info[4], int info_type) {

  __asm__ volatile(

      "mov %%ebx, %%edi\n"

      "cpuid\n"

      "xchg %%edi, %%ebx\n"

      : "=a"(cpu_info[0]), "=D"(cpu_info[1]), "=c"(cpu_info[2]),

        "=d"(cpu_info[3])

      : "a"(info_type), "c"(0));

}

#elif defined(__i386__) || defined(__x86_64__)

static WEBP_INLINE void GetCPUInfo(int cpu_info[4], int info_type) {

  __asm__ volatile("cpuid\n"

                   : "=a"(cpu_info[0]), "=b"(cpu_info[1]), "=c"(cpu_info[2]),

                     "=d"(cpu_info[3])

                   : "a"(info_type), "c"(0));

}

#elif defined(_MSC_VER) && (defined(_M_X64) || defined(_M_IX86))

#if defined(_MSC_FULL_VER) && _MSC_FULL_VER >= 150030729  // >= VS2008 SP1

#include <intrin.h>

#define GetCPUInfo(info, type) __cpuidex(info, type, 0)  // set ecx=0

#define WEBP_HAVE_MSC_CPUID

#elif _MSC_VER > 1310

#include <intrin.h>

#define GetCPUInfo __cpuid

#define WEBP_HAVE_MSC_CPUID

#endif

#endif

// NaCl has no support for xgetbv or the raw opcode.

#if !defined(__native_client__) && (defined(__i386__) || defined(__x86_64__))

static WEBP_INLINE uint64_t xgetbv(void) {

  const uint32_t ecx = 0;

  uint32_t eax, edx;

  // Use the raw opcode for xgetbv for compatibility with older toolchains.

  __asm__ volatile(".byte 0x0f, 0x01, 0xd0\n"

                   : "=a"(eax), "=d"(edx)

                   : "c"(ecx));

  return ((uint64_t)edx << 32) | eax;

}

#elif (defined(_M_X64) || defined(_M_IX86)) && defined(_MSC_FULL_VER) && \

    _MSC_FULL_VER >= 160040219  // >= VS2010 SP1

#include <immintrin.h>

#define xgetbv() _xgetbv(0)

#elif defined(_MSC_VER) && defined(_M_IX86)

static WEBP_INLINE uint64_t xgetbv(void) {

  uint32_t eax_, edx_;

  __asm {

    xor ecx, ecx  // ecx = 0

    // Use the raw opcode for xgetbv for compatibility with older toolchains.

    __asm _emit 0x0f __asm _emit 0x01 __asm _emit 0xd0

    mov eax_, eax

    mov edx_, edx

  }

  return ((uint64_t)edx_ << 32) | eax_;

}

#else

#define xgetbv() 0U  // no AVX for older x64 or unrecognized toolchains.

#endif

#if defined(__i386__) || defined(__x86_64__) || defined(WEBP_HAVE_MSC_CPUID)

// helper function for run-time detection of slow SSSE3 platforms

static int CheckSlowModel(int info) {

  // Table listing display models with longer latencies for the bsr instruction

  // (ie 2 cycles vs 10/16 cycles) and some SSSE3 instructions like pshufb.

  // Refer to Intel 64 and IA-32 Architectures Optimization Reference Manual.

  static const uint8_t kSlowModels[] = {

      0x37, 0x4a, 0x4d,  // Silvermont Microarchitecture

      0x1c, 0x26, 0x27   // Atom Microarchitecture

  };

  const uint32_t model = ((info & 0xf0000) >> 12) | ((info >> 4) & 0xf);

  const uint32_t family = (info >> 8) & 0xf;

  if (family == 0x06) {

    size_t i;

    for (i = 0; i < sizeof(kSlowModels) / sizeof(kSlowModels[0]); ++i) {

      if (model == kSlowModels[i]) return 1;

    }

  }

  return 0;

}

static int x86CPUInfo(CPUFeature feature) {

  int max_cpuid_value;

  int cpu_info[4];

  int is_intel = 0;

  // get the highest feature value cpuid supports

  GetCPUInfo(cpu_info, 0);

  max_cpuid_value = cpu_info[0];

  if (max_cpuid_value < 1) {

    return 0;

  } else {

    const int VENDOR_ID_INTEL_EBX = 0x756e6547;  // uneG

    const int VENDOR_ID_INTEL_EDX = 0x49656e69;  // Ieni

    const int VENDOR_ID_INTEL_ECX = 0x6c65746e;  // letn

    is_intel = (cpu_info[1] == VENDOR_ID_INTEL_EBX &&

                cpu_info[2] == VENDOR_ID_INTEL_ECX &&

                cpu_info[3] == VENDOR_ID_INTEL_EDX);  // genuine Intel?

  }

  GetCPUInfo(cpu_info, 1);

  if (feature == kSSE2) {

    return !!(cpu_info[3] & (1 << 26));

  }

  if (feature == kSSE3) {

    return !!(cpu_info[2] & (1 << 0));

  }

  if (feature == kSlowSSSE3) {

    if (is_intel && (cpu_info[2] & (1 << 9))) {  // SSSE3?

      return CheckSlowModel(cpu_info[0]);

    }

    return 0;

  }

  if (feature == kSSE4_1) {

    return !!(cpu_info[2] & (1 << 19));

  }

  if (feature == kAVX) {

    // bits 27 (OSXSAVE) & 28 (256-bit AVX)

    if ((cpu_info[2] & 0x18000000) == 0x18000000) {

      // XMM state and YMM state enabled by the OS.

      return (xgetbv() & 0x6) == 0x6;

    }

  }

  if (feature == kAVX2) {

    if (x86CPUInfo(kAVX) && max_cpuid_value >= 7) {

      GetCPUInfo(cpu_info, 7);

      return !!(cpu_info[1] & (1 << 5));

    }

  }

  return 0;

}

WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;

VP8CPUInfo VP8GetCPUInfo = x86CPUInfo;

#elif defined(WEBP_ANDROID_NEON)  // NB: needs to be before generic NEON test.

static int AndroidCPUInfo(CPUFeature feature) {

  const AndroidCpuFamily cpu_family = android_getCpuFamily();

  const uint64_t cpu_features = android_getCpuFeatures();

  if (feature == kNEON) {

    return cpu_family == ANDROID_CPU_FAMILY_ARM &&

           (cpu_features & ANDROID_CPU_ARM_FEATURE_NEON) != 0;

  }

  return 0;

}

WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;

VP8CPUInfo VP8GetCPUInfo = AndroidCPUInfo;

#elif defined(__EMSCRIPTEN__)     // also needs to be before generic NEON test

// Use compile flags as an indicator of SIMD support instead of a runtime check.

static int wasmCPUInfo(CPUFeature feature) {

  switch (feature) {

#ifdef WEBP_HAVE_SSE2

    case kSSE2:

      return 1;

#endif

#ifdef WEBP_HAVE_SSE41

    case kSSE3:

    case kSlowSSSE3:

    case kSSE4_1:

      return 1;

#endif

#ifdef WEBP_HAVE_AVX2

    case kAVX2:

      return 1;

#endif

#ifdef WEBP_HAVE_NEON

    case kNEON:

      return 1;

#endif

    default:

      break;

  }

  return 0;

}

WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;

VP8CPUInfo VP8GetCPUInfo = wasmCPUInfo;

#elif defined(WEBP_HAVE_NEON)

// In most cases this function doesn't check for NEON support (it's assumed by

// the configuration), but enables turning off NEON at runtime, for testing

// purposes, by setting VP8GetCPUInfo = NULL.

static int armCPUInfo(CPUFeature feature) {

  if (feature != kNEON) return 0;

#if defined(__linux__) && defined(WEBP_HAVE_NEON_RTCD)

  {

    int has_neon = 0;

    char line[200];

    FILE* const cpuinfo = fopen("/proc/cpuinfo", "r");

    if (cpuinfo == NULL) return 0;

    while (fgets(line, sizeof(line), cpuinfo)) {

      if (!strncmp(line, "Features", 8)) {

        if (strstr(line, " neon ") != NULL) {

          has_neon = 1;

          break;

        }

      }

    }

    fclose(cpuinfo);

    return has_neon;

  }

#else

  return 1;

#endif

}

WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;

VP8CPUInfo VP8GetCPUInfo = armCPUInfo;

#elif defined(WEBP_USE_MIPS32) || defined(WEBP_USE_MIPS_DSP_R2) || \

    defined(WEBP_USE_MSA)

static int mipsCPUInfo(CPUFeature feature) {

  if ((feature == kMIPS32) || (feature == kMIPSdspR2) || (feature == kMSA)) {

    return 1;

  } else {

    return 0;

  }

}

WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;

VP8CPUInfo VP8GetCPUInfo = mipsCPUInfo;

#else

WEBP_EXTERN VP8CPUInfo VP8GetCPUInfo;

VP8CPUInfo VP8GetCPUInfo = NULL;

#endif