/src/php-src/Zend/Optimizer/zend_inference.c

Source
/*
   +----------------------------------------------------------------------+
   | Zend Engine, e-SSA based Type & Range Inference                      |
   +----------------------------------------------------------------------+
   | Copyright © The PHP Group and Contributors.                          |
   +----------------------------------------------------------------------+
   | This source file is subject to the Modified BSD License that is      |
   | bundled with this package in the file LICENSE, and is available      |
   | through the World Wide Web at <https://www.php.net/license/>.        |
   |                                                                      |
   | SPDX-License-Identifier: BSD-3-Clause                                |
   +----------------------------------------------------------------------+
   | Authors: Dmitry Stogov <dmitry@php.net>                              |
   +----------------------------------------------------------------------+
*/

#include "zend_compile.h"
#include "zend_generators.h"
#include "zend_inference.h"
#include "zend_func_info.h"
#include "zend_call_graph.h"
#include "zend_closures.h"
#include "zend_worklist.h"
#include "zend_optimizer_internal.h"

/* The used range inference algorithm is described in:
 *     V. Campos, R. Rodrigues, I. de Assis Costa and F. Pereira.
 *     "Speed and Precision in Range Analysis", SBLP'12.
 *
 * There are a couple degrees of freedom, we use:
 *  * Propagation on SCCs.
 *  * e-SSA for live range splitting.
 *  * Only intra-procedural inference.
 *  * Widening with warmup passes, but without jump sets.
 */

/* Whether to handle symbolic range constraints */
#define SYM_RANGE

/* Whether to handle negative range constraints */
/* Negative range inference is buggy, so disabled for now */
#undef NEG_RANGE

/* Number of warmup passes to use prior to widening */
#define RANGE_WARMUP_PASSES 16

/* Logging for range inference in general */
#if 0
#define LOG_SSA_RANGE(...) fprintf(stderr, __VA_ARGS__)
#else
#define LOG_SSA_RANGE(...)
#endif

/* Logging for negative range constraints */
#if 0
#define LOG_NEG_RANGE(...) fprintf(stderr, __VA_ARGS__)
#else
#define LOG_NEG_RANGE(...)
#endif

/* Pop elements in unspecified order from worklist until it is empty */
#define WHILE_WORKLIST(worklist, len, i) do { \
  bool _done = 0; \
  while (!_done) { \
    _done = 1; \
    ZEND_BITSET_FOREACH(worklist, len, i) { \
      zend_bitset_excl(worklist, i); \
      _done = 0;

#define WHILE_WORKLIST_END() \
    } ZEND_BITSET_FOREACH_END(); \
  } \
} while (0)

#define CHECK_SCC_VAR(var2) \
  do { \
    if (!ssa->vars[var2].no_val) { \
      if (ssa->vars[var2].scc < 0) { \
        zend_ssa_check_scc_var(op_array, ssa, var2, index, stack); \
      } \
      if (ssa->vars[var2].scc < ssa->vars[var].scc) { \
        ssa->vars[var].scc = ssa->vars[var2].scc; \
        is_root = 0; \
      } \
    } \
  } while (0)

#define CHECK_SCC_ENTRY(var2) \
  do { \
    if (ssa->vars[var2].scc != ssa->vars[var].scc) { \
      ssa->vars[var2].scc_entry = 1; \
    } \
  } while (0)

#define ADD_SCC_VAR(_var) \
  do { \
    if (ssa->vars[_var].scc == scc && \
        !(ssa->var_info[_var].type & MAY_BE_REF)) { \
      zend_bitset_incl(worklist, _var); \
    } \
  } while (0)

#define ADD_SCC_VAR_1(_var) \
  do { \
    if (ssa->vars[_var].scc == scc && \
        !(ssa->var_info[_var].type & MAY_BE_REF) && \
        !zend_bitset_in(visited, _var)) { \
      zend_bitset_incl(worklist, _var); \
    } \
  } while (0)

#define FOR_EACH_DEFINED_VAR(line, MACRO) \
  do { \
    if (ssa->ops[line].op1_def >= 0) { \
      MACRO(ssa->ops[line].op1_def); \
    } \
    if (ssa->ops[line].op2_def >= 0) { \
      MACRO(ssa->ops[line].op2_def); \
    } \
    if (ssa->ops[line].result_def >= 0) { \
      MACRO(ssa->ops[line].result_def); \
    } \
    if (op_array->opcodes[line].opcode == ZEND_OP_DATA) { \
      if (ssa->ops[line-1].op1_def >= 0) { \
        MACRO(ssa->ops[line-1].op1_def); \
      } \
      if (ssa->ops[line-1].op2_def >= 0) { \
        MACRO(ssa->ops[line-1].op2_def); \
      } \
      if (ssa->ops[line-1].result_def >= 0) { \
        MACRO(ssa->ops[line-1].result_def); \
      } \
    } else if ((uint32_t)line+1 < op_array->last && \
               op_array->opcodes[line+1].opcode == ZEND_OP_DATA) { \
      if (ssa->ops[line+1].op1_def >= 0) { \
        MACRO(ssa->ops[line+1].op1_def); \
      } \
      if (ssa->ops[line+1].op2_def >= 0) { \
        MACRO(ssa->ops[line+1].op2_def); \
      } \
      if (ssa->ops[line+1].result_def >= 0) { \
        MACRO(ssa->ops[line+1].result_def); \
      } \
    } \
  } while (0)


#define FOR_EACH_VAR_USAGE(_var, MACRO) \
  do { \
    zend_ssa_phi *p = ssa->vars[_var].phi_use_chain; \
    int use = ssa->vars[_var].use_chain; \
    while (use >= 0) { \
      FOR_EACH_DEFINED_VAR(use, MACRO); \
      use = zend_ssa_next_use(ssa->ops, _var, use); \
    } \
    p = ssa->vars[_var].phi_use_chain; \
    while (p) { \
      MACRO(p->ssa_var); \
      p = zend_ssa_next_use_phi(ssa, _var, p); \
    } \
  } while (0)

static inline bool add_will_overflow(zend_long a, zend_long b) {
  return (b > 0 && a > ZEND_LONG_MAX - b)
    || (b < 0 && a < ZEND_LONG_MIN - b);
}
#if 0
static inline bool sub_will_overflow(zend_long a, zend_long b) {
  return (b > 0 && a < ZEND_LONG_MIN + b)
    || (b < 0 && a > ZEND_LONG_MAX + b);
}
#endif

#if 0
/* Recursive Pearce's SCC algorithm implementation */
static void zend_ssa_check_scc_var(const zend_op_array *op_array, zend_ssa *ssa, int var, int *index, zend_worklist_stack *stack) /* {{{ */
{
  int is_root = 1;
#ifdef SYM_RANGE
  zend_ssa_phi *p;
#endif

  ssa->vars[var].scc = *index;
  (*index)++;

  FOR_EACH_VAR_USAGE(var, CHECK_SCC_VAR);

#ifdef SYM_RANGE
  /* Process symbolic control-flow constraints */
  p = ssa->vars[var].sym_use_chain;
  while (p) {
    CHECK_SCC_VAR(p->ssa_var);
    p = p->sym_use_chain;
  }
#endif

  if (is_root) {
    ssa->sccs--;
    while (stack->len > 0) {
      int var2 = zend_worklist_stack_peek(stack);
      if (ssa->vars[var2].scc < ssa->vars[var].scc) {
        break;
      }
      zend_worklist_stack_pop(stack);
      ssa->vars[var2].scc = ssa->sccs;
      (*index)--;
    }
    ssa->vars[var].scc = ssa->sccs;
    ssa->vars[var].scc_entry = 1;
    (*index)--;
  } else {
    zend_worklist_stack_push(stack, var);
  }
}
/* }}} */

ZEND_API void zend_ssa_find_sccs(const zend_op_array *op_array, zend_ssa *ssa) /* {{{ */
{
  int index = 0;
  zend_worklist_stack stack;
  int j;
  ALLOCA_FLAG(stack_use_heap)

  ZEND_WORKLIST_STACK_ALLOCA(&stack, ssa->vars_count, stack_use_heap);

  /* Find SCCs using Pearce's algorithm. */
  ssa->sccs = ssa->vars_count;
  for (j = 0; j < ssa->vars_count; j++) {
    if (!ssa->vars[j].no_val && ssa->vars[j].scc < 0) {
      zend_ssa_check_scc_var(op_array, ssa, j, &index, &stack);
    }
  }

  if (ssa->sccs) {
    /* Shift SCC indexes. */
    for (j = 0; j < ssa->vars_count; j++) {
      if (ssa->vars[j].scc >= 0) {
        ssa->vars[j].scc -= ssa->sccs;
      }
    }
  }
  ssa->sccs = ssa->vars_count - ssa->sccs;

  for (j = 0; j < ssa->vars_count; j++) {
    if (ssa->vars[j].scc >= 0) {
      int var = j;
      FOR_EACH_VAR_USAGE(var, CHECK_SCC_ENTRY);
    }
  }

  ZEND_WORKLIST_STACK_FREE_ALLOCA(&stack, stack_use_heap);
}
/* }}} */

#else
/* Iterative Pearce's SCC algorithm implementation */

typedef struct _zend_scc_iterator {
  int               state;
  int               last;
  union {
    int           use;
    zend_ssa_phi *phi;
  };
} zend_scc_iterator;

static int zend_scc_next(const zend_op_array *op_array, const zend_ssa *ssa, int var, zend_scc_iterator *iterator) /* {{{ */
{
  zend_ssa_phi *phi;
  int use, var2;

  switch (iterator->state) {
    case 0:                       goto state_0;
    case 1:  use = iterator->use; goto state_1;
    case 2:  use = iterator->use; goto state_2;
    case 3:  use = iterator->use; goto state_3;
    case 4:  use = iterator->use; goto state_4;
    case 5:  use = iterator->use; goto state_5;
    case 6:  use = iterator->use; goto state_6;
    case 7:  use = iterator->use; goto state_7;
    case 8:  use = iterator->use; goto state_8;
    case 9:  phi = iterator->phi; goto state_9;
#ifdef SYM_RANGE
    case 10: phi = iterator->phi; goto state_10;
#endif
    case 11:                      goto state_11;
  }

state_0:
  use = ssa->vars[var].use_chain;
  while (use >= 0) {
    iterator->use = use;
    var2 = ssa->ops[use].op1_def;
    if (var2 >= 0 && !ssa->vars[var2].no_val) {
      iterator->state = 1;
      return var2;
    }
state_1:
    var2 = ssa->ops[use].op2_def;
    if (var2 >= 0 && !ssa->vars[var2].no_val) {
      iterator->state = 2;
      return var2;
    }
state_2:
    var2 = ssa->ops[use].result_def;
    if (var2 >= 0 && !ssa->vars[var2].no_val) {
      iterator->state = 3;
      return var2;
    }
state_3:
    if (op_array->opcodes[use].opcode == ZEND_OP_DATA) {
      var2 = ssa->ops[use-1].op1_def;
      if (var2 >= 0 && !ssa->vars[var2].no_val) {
        iterator->state = 4;
        return var2;
      }
state_4:
      var2 = ssa->ops[use-1].op2_def;
      if (var2 >= 0 && !ssa->vars[var2].no_val) {
        iterator->state = 5;
        return var2;
      }
state_5:
      var2 = ssa->ops[use-1].result_def;
      if (var2 >= 0 && !ssa->vars[var2].no_val) {
        iterator->state = 8;
        return var2;
      }
    } else if ((uint32_t)use+1 < op_array->last &&
               op_array->opcodes[use+1].opcode == ZEND_OP_DATA) {
      var2 = ssa->ops[use+1].op1_def;
      if (var2 >= 0 && !ssa->vars[var2].no_val) {
        iterator->state = 6;
        return var2;
      }
state_6:
      var2 = ssa->ops[use+1].op2_def;
      if (var2 >= 0 && !ssa->vars[var2].no_val) {
        iterator->state = 7;
        return var2;
      }
state_7:
      var2 = ssa->ops[use+1].result_def;
      if (var2 >= 0 && !ssa->vars[var2].no_val) {
        iterator->state = 8;
        return var2;
      }
    }
state_8:
    use = zend_ssa_next_use(ssa->ops, var, use);
  }

  phi = ssa->vars[var].phi_use_chain;
  while (phi) {
    var2 = phi->ssa_var;
    if (!ssa->vars[var2].no_val) {
      iterator->state = 9;
      iterator->phi = phi;
      return var2;
    }
state_9:
    phi = zend_ssa_next_use_phi(ssa, var, phi);
  }

#ifdef SYM_RANGE
  /* Process symbolic control-flow constraints */
  phi = ssa->vars[var].sym_use_chain;
  while (phi) {
    var2 = phi->ssa_var;
    if (!ssa->vars[var2].no_val) {
      iterator->state = 10;
      iterator->phi = phi;
      return var2;
    }
state_10:
    phi = phi->sym_use_chain;
  }
#endif

  iterator->state = 11;
state_11:
  return -1;
}
/* }}} */

static void zend_ssa_check_scc_var(const zend_op_array *op_array, zend_ssa *ssa, int var, int *index, zend_worklist_stack *stack, zend_worklist_stack *vstack, zend_scc_iterator *iterators) /* {{{ */
{
restart:
  zend_worklist_stack_push(vstack, var);
  iterators[var].state = 0;
  iterators[var].last = -1;
  ssa->vars[var].scc_entry = 1;
  ssa->vars[var].scc = *index;
  (*index)++;

  while (vstack->len > 0) {
    var = zend_worklist_stack_peek(vstack);
    while (1) {
      int var2;

      if (iterators[var].last >= 0) {
        /* finish edge */
        var2 = iterators[var].last;
        if (ssa->vars[var2].scc < ssa->vars[var].scc) {
          ssa->vars[var].scc = ssa->vars[var2].scc;
          ssa->vars[var].scc_entry = 0;
        }
      }
      var2 = zend_scc_next(op_array, ssa, var, iterators + var);
      iterators[var].last = var2;
      if (var2 < 0) break;
      /* begin edge */
      if (ssa->vars[var2].scc < 0) {
        var = var2;
        goto restart;
      }
    }

    /* finish visiting */
    zend_worklist_stack_pop(vstack);
    if (ssa->vars[var].scc_entry) {
      ssa->sccs--;
      while (stack->len > 0) {
        int var2 = zend_worklist_stack_peek(stack);
        if (ssa->vars[var2].scc < ssa->vars[var].scc) {
          break;
        }
        zend_worklist_stack_pop(stack);
        ssa->vars[var2].scc = ssa->sccs;
        (*index)--;
      }
      ssa->vars[var].scc = ssa->sccs;
      (*index)--;
    } else {
      zend_worklist_stack_push(stack, var);
    }
  }
}
/* }}} */

ZEND_API void zend_ssa_find_sccs(const zend_op_array *op_array, zend_ssa *ssa) /* {{{ */
{
  int index = 0;
  zend_worklist_stack stack, vstack;
  zend_scc_iterator *iterators;
  int j;
  ALLOCA_FLAG(stack_use_heap)
  ALLOCA_FLAG(vstack_use_heap)
  ALLOCA_FLAG(iterators_use_heap)

  iterators = do_alloca(sizeof(zend_scc_iterator) * ssa->vars_count, iterators_use_heap);
  ZEND_WORKLIST_STACK_ALLOCA(&vstack, ssa->vars_count, vstack_use_heap);
  ZEND_WORKLIST_STACK_ALLOCA(&stack, ssa->vars_count, stack_use_heap);

  /* Find SCCs using Pearce's algorithm. */
  ssa->sccs = ssa->vars_count;
  for (j = 0; j < ssa->vars_count; j++) {
    if (!ssa->vars[j].no_val && ssa->vars[j].scc < 0) {
      zend_ssa_check_scc_var(op_array, ssa, j, &index, &stack, &vstack, iterators);
    }
  }

  if (ssa->sccs) {
    /* Shift SCC indexes. */
    for (j = 0; j < ssa->vars_count; j++) {
      if (ssa->vars[j].scc >= 0) {
        ssa->vars[j].scc -= ssa->sccs;
      }
    }
  }
  ssa->sccs = ssa->vars_count - ssa->sccs;

  for (j = 0; j < ssa->vars_count; j++) {
    if (ssa->vars[j].scc >= 0) {
      int var = j;
      FOR_EACH_VAR_USAGE(var, CHECK_SCC_ENTRY);
    }
  }

  ZEND_WORKLIST_STACK_FREE_ALLOCA(&stack, stack_use_heap);
  ZEND_WORKLIST_STACK_FREE_ALLOCA(&vstack, vstack_use_heap);
  free_alloca(iterators, iterators_use_heap);
}
/* }}} */

#endif

ZEND_API void zend_ssa_find_false_dependencies(const zend_op_array *op_array, const zend_ssa *ssa) /* {{{ */
{
  zend_ssa_var *ssa_vars = ssa->vars;
  const zend_ssa_op *ssa_ops = ssa->ops;
  int ssa_vars_count = ssa->vars_count;
  zend_bitset worklist;
  int i, use;
  const zend_ssa_phi *p;
  ALLOCA_FLAG(use_heap);

  if (!op_array->function_name || !ssa->vars || !ssa->ops) {
    return;
  }

  worklist = do_alloca(sizeof(zend_ulong) * zend_bitset_len(ssa_vars_count), use_heap);
  memset(worklist, 0, sizeof(zend_ulong) * zend_bitset_len(ssa_vars_count));

  for (i = 0; i < ssa_vars_count; i++) {
    ssa_vars[i].no_val = 1; /* mark as unused */
    use = ssa->vars[i].use_chain;
    while (use >= 0) {
      if (!zend_ssa_is_no_val_use(&op_array->opcodes[use], &ssa->ops[use], i)) {
        ssa_vars[i].no_val = 0; /* used directly */
        zend_bitset_incl(worklist, i);
        break;
      }
      use = zend_ssa_next_use(ssa_ops, i, use);
    }
  }

  WHILE_WORKLIST(worklist, zend_bitset_len(ssa_vars_count), i) {
    if (ssa_vars[i].definition_phi) {
      /* mark all possible sources as used */
      p = ssa_vars[i].definition_phi;
      if (p->pi >= 0) {
        if (ssa_vars[p->sources[0]].no_val) {
          ssa_vars[p->sources[0]].no_val = 0; /* used indirectly */
          zend_bitset_incl(worklist, p->sources[0]);
        }
      } else {
        for (uint32_t j = 0; j < ssa->cfg.blocks[p->block].predecessors_count; j++) {
          ZEND_ASSERT(p->sources[j] >= 0);
          if (ssa->vars[p->sources[j]].no_val) {
            ssa_vars[p->sources[j]].no_val = 0; /* used indirectly */
            zend_bitset_incl(worklist, p->sources[j]);
          }
        }
      }
    }
  } WHILE_WORKLIST_END();

  free_alloca(worklist, use_heap);
}
/* }}} */

/* From "Hacker's Delight" */
static zend_ulong minOR(zend_ulong a, zend_ulong b, zend_ulong c, zend_ulong d)
{
  zend_ulong m, temp;

  m = Z_UL(1) << (sizeof(zend_ulong) * 8 - 1);
  while (m != 0) {
    if (~a & c & m) {
      temp = (a | m) & -m;
      if (temp <= b) {
        a = temp;
        break;
      }
    } else if (a & ~c & m) {
      temp = (c | m) & -m;
      if (temp <= d) {
        c = temp;
        break;
      }
    }
    m = m >> 1;
  }
  return a | c;
}

static zend_ulong maxOR(zend_ulong a, zend_ulong b, zend_ulong c, zend_ulong d)
{
  zend_ulong m, temp;

  m = Z_UL(1) << (sizeof(zend_ulong) * 8 - 1);
  while (m != 0) {
    if (b & d & m) {
      temp = (b - m) | (m - 1);
      if (temp >= a) {
        b = temp;
        break;
      }
      temp = (d - m) | (m - 1);
      if (temp >= c) {
        d = temp;
        break;
      }
    }
    m = m >> 1;
  }
  return b | d;
}

static zend_ulong minAND(zend_ulong a, zend_ulong b, zend_ulong c, zend_ulong d)
{
  zend_ulong m, temp;

  m = Z_UL(1) << (sizeof(zend_ulong) * 8 - 1);
  while (m != 0) {
    if (~a & ~c & m) {
      temp = (a | m) & -m;
      if (temp <= b) {
        a = temp;
        break;
      }
      temp = (c | m) & -m;
      if (temp <= d) {
        c = temp;
        break;
      }
    }
    m = m >> 1;
  }
  return a & c;
}

static zend_ulong maxAND(zend_ulong a, zend_ulong b, zend_ulong c, zend_ulong d)
{
  zend_ulong m, temp;

  m = Z_UL(1) << (sizeof(zend_ulong) * 8 - 1);
  while (m != 0) {
    if (b & ~d & m) {
      temp = (b | ~m) | (m - 1);
      if (temp >= a) {
        b = temp;
        break;
      }
    } else if (~b & d & m) {
      temp = (d | ~m) | (m - 1);
      if (temp >= c) {
        d = temp;
        break;
      }
    }
    m = m >> 1;
  }
  return b & d;
}

/* Based on "Hacker's Delight" */

/*
0: + + + + 0 0 0 0 => 0 0 + min/max
2: + + - + 0 0 1 0 => 1 0 ? min(a,b,c,-1)/max(a,b,0,d)
3: + + - - 0 0 1 1 => 1 1 - min/max
8: - + + + 1 0 0 0 => 1 0 ? min(a,-1,b,d)/max(0,b,c,d)
a: - + - + 1 0 1 0 => 1 0 ? MIN(a,c)/max(0,b,0,d)
b: - + - - 1 0 1 1 => 1 1 - c/-1
c: - - + + 1 1 0 0 => 1 1 - min/max
e: - - - + 1 1 1 0 => 1 1 - a/-1
f  - - - - 1 1 1 1 => 1 1 - min/max
*/
static void zend_ssa_range_or(zend_long a, zend_long b, zend_long c, zend_long d, zend_ssa_range *tmp)
{
  int x = ((a < 0) ? 8 : 0) |
          ((b < 0) ? 4 : 0) |
          ((c < 0) ? 2 : 0) |
          ((d < 0) ? 1 : 0);
  switch (x) {
    case 0x0:
    case 0x3:
    case 0xc:
    case 0xf:
      tmp->min = minOR(a, b, c, d);
      tmp->max = maxOR(a, b, c, d);
      break;
    case 0x2:
      tmp->min = minOR(a, b, c, -1);
      tmp->max = maxOR(a, b, 0, d);
      break;
    case 0x8:
      tmp->min = minOR(a, -1, c, d);
      tmp->max = maxOR(0, b, c, d);
      break;
    case 0xa:
      tmp->min = MIN(a, c);
      tmp->max = maxOR(0, b, 0, d);
      break;
    case 0xb:
      tmp->min = c;
      tmp->max = -1;
      break;
    case 0xe:
      tmp->min = a;
      tmp->max = -1;
      break;
  }
}

/*
0: + + + + 0 0 0 0 => 0 0 + min/max
2: + + - + 0 0 1 0 => 0 0 + 0/b
3: + + - - 0 0 1 1 => 0 0 + min/max
8: - + + + 1 0 0 0 => 0 0 + 0/d
a: - + - + 1 0 1 0 => 1 0 ? min(a,-1,c,-1)/NAX(b,d)
b: - + - - 1 0 1 1 => 1 0 ? min(a,-1,c,d)/max(0,b,c,d)
c: - - + + 1 1 0 0 => 1 1 - min/max
e: - - - + 1 1 1 0 => 1 0 ? min(a,b,c,-1)/max(a,b,0,d)
f  - - - - 1 1 1 1 => 1 1 - min/max
*/
static void zend_ssa_range_and(zend_long a, zend_long b, zend_long c, zend_long d, zend_ssa_range *tmp)
{
  int x = ((a < 0) ? 8 : 0) |
          ((b < 0) ? 4 : 0) |
          ((c < 0) ? 2 : 0) |
          ((d < 0) ? 1 : 0);
  switch (x) {
    case 0x0:
    case 0x3:
    case 0xc:
    case 0xf:
      tmp->min = minAND(a, b, c, d);
      tmp->max = maxAND(a, b, c, d);
      break;
    case 0x2:
      tmp->min = 0;
      tmp->max = b;
      break;
    case 0x8:
      tmp->min = 0;
      tmp->max = d;
      break;
    case 0xa:
      tmp->min = minAND(a, -1, c, -1);
      tmp->max = MAX(b, d);
      break;
    case 0xb:
      tmp->min = minAND(a, -1, c, d);
      tmp->max = maxAND(0, b, c, d);
      break;
    case 0xe:
      tmp->min = minAND(a, b, c, -1);
      tmp->max = maxAND(a, b, 0, d);
      break;
  }
}

static inline bool zend_abs_range(
    zend_long min, zend_long max, zend_long *abs_min, zend_long *abs_max) {
  if (min == ZEND_LONG_MIN) {
    /* Cannot take absolute value of LONG_MIN  */
    return 0;
  }

  if (min >= 0) {
    *abs_min = min;
    *abs_max = max;
  } else if (max <= 0) {
    *abs_min = -max;
    *abs_max = -min;
  } else {
    /* Range crossing zero */
    *abs_min = 0;
    *abs_max = MAX(max, -min);
  }

  return 1;
}

static inline zend_long safe_shift_left(zend_long n, zend_long s) {
  return (zend_long) ((zend_ulong) n << (zend_ulong) s);
}

static inline bool shift_left_overflows(zend_long n, zend_long s) {
  /* This considers shifts that shift in the sign bit to be overflowing as well */
  if (n >= 0) {
    return s >= SIZEOF_ZEND_LONG * 8 - 1 || safe_shift_left(n, s) < n;
  } else {
    return s >= SIZEOF_ZEND_LONG * 8 || safe_shift_left(n, s) > n;
  }
}

/* If b does not divide a exactly, return the two adjacent values between which the real result
 * lies. */
static void float_div(zend_long a, zend_long b, zend_long *r1, zend_long *r2) {
  *r1 = *r2 = a / b;
  if (a % b != 0) {
    if (*r2 < 0) {
      (*r2)--;
    } else {
      (*r2)++;
    }
  }
}

static bool zend_inference_calc_binary_op_range(
    const zend_op_array *op_array, const zend_ssa *ssa,
    const zend_op *opline, const zend_ssa_op *ssa_op, uint8_t opcode, zend_ssa_range *tmp) {
  zend_long op1_min, op2_min, op1_max, op2_max, t1, t2, t3, t4;

  switch (opcode) {
    case ZEND_ADD:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        op1_min = OP1_MIN_RANGE();
        op2_min = OP2_MIN_RANGE();
        op1_max = OP1_MAX_RANGE();
        op2_max = OP2_MAX_RANGE();
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          zend_add_will_overflow(op1_min, op2_min)) {
          tmp->underflow = 1;
          tmp->min = ZEND_LONG_MIN;
        } else {
          tmp->min = op1_min + op2_min;
        }
        if (OP1_RANGE_OVERFLOW() ||
          OP2_RANGE_OVERFLOW() ||
          zend_add_will_overflow(op1_max, op2_max)) {
          tmp->overflow = 1;
          tmp->max = ZEND_LONG_MAX;
        } else {
          tmp->max = op1_max + op2_max;
        }
        return 1;
      }
      break;
    case ZEND_SUB:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        op1_min = OP1_MIN_RANGE();
        op2_min = OP2_MIN_RANGE();
        op1_max = OP1_MAX_RANGE();
        op2_max = OP2_MAX_RANGE();
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_OVERFLOW() ||
          zend_sub_will_overflow(op1_min, op2_max)) {
          tmp->underflow = 1;
          tmp->min = ZEND_LONG_MIN;
        } else {
          tmp->min = op1_min - op2_max;
        }
        if (OP1_RANGE_OVERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          zend_sub_will_overflow(op1_max, op2_min)) {
          tmp->overflow = 1;
          tmp->max = ZEND_LONG_MAX;
        } else {
          tmp->max = op1_max - op2_min;
        }
        return 1;
      }
      break;
    case ZEND_MUL:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        double dummy;
        zend_long t1_overflow, t2_overflow, t3_overflow, t4_overflow;
        op1_min = OP1_MIN_RANGE();
        op2_min = OP2_MIN_RANGE();
        op1_max = OP1_MAX_RANGE();
        op2_max = OP2_MAX_RANGE();
        /* Suppress uninit variable warnings, these will only be used if the overflow
         * flags are all false. */
        t1 = t2 = t3 = t4 = 0;
        ZEND_SIGNED_MULTIPLY_LONG(op1_min, op2_min, t1, dummy, t1_overflow);
        ZEND_SIGNED_MULTIPLY_LONG(op1_min, op2_max, t2, dummy, t2_overflow);
        ZEND_SIGNED_MULTIPLY_LONG(op1_max, op2_min, t3, dummy, t3_overflow);
        ZEND_SIGNED_MULTIPLY_LONG(op1_max, op2_max, t4, dummy, t4_overflow);
        (void) dummy;

        // FIXME: more careful overflow checks?
        if (OP1_RANGE_UNDERFLOW() || OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW() || OP2_RANGE_OVERFLOW()  ||
          t1_overflow || t2_overflow || t3_overflow || t4_overflow
        ) {
          tmp->underflow = 1;
          tmp->overflow = 1;
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          tmp->min = MIN(MIN(t1, t2), MIN(t3, t4));
          tmp->max = MAX(MAX(t1, t2), MAX(t3, t4));
        }
        return 1;
      }
      break;
    case ZEND_DIV:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        op1_min = OP1_MIN_RANGE();
        op2_min = OP2_MIN_RANGE();
        op1_max = OP1_MAX_RANGE();
        op2_max = OP2_MAX_RANGE();

        /* If op2 crosses zero, then floating point values close to zero might be
         * possible, which will result in arbitrarily large results (overflow). Also
         * avoid dividing LONG_MIN by -1, which is UB. */
        if (OP1_RANGE_UNDERFLOW() || OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW() || OP2_RANGE_OVERFLOW() ||
          (op2_min <= 0 && op2_max >= 0) ||
          (op1_min == ZEND_LONG_MIN && op2_max == -1)
        ) {
          tmp->underflow = 1;
          tmp->overflow = 1;
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          zend_long t1_, t2_, t3_, t4_;
          float_div(op1_min, op2_min, &t1, &t1_);
          float_div(op1_min, op2_max, &t2, &t2_);
          float_div(op1_max, op2_min, &t3, &t3_);
          float_div(op1_max, op2_max, &t4, &t4_);

          tmp->min = MIN(MIN(MIN(t1, t2), MIN(t3, t4)), MIN(MIN(t1_, t2_), MIN(t3_, t4_)));
          tmp->max = MAX(MAX(MAX(t1, t2), MAX(t3, t4)), MAX(MAX(t1_, t2_), MAX(t3_, t4_)));
        }
        return 1;
      }
      break;
    case ZEND_MOD:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW()  ||
          OP2_RANGE_OVERFLOW()) {
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          zend_long op2_abs_min, op2_abs_max;

          op1_min = OP1_MIN_RANGE();
          op2_min = OP2_MIN_RANGE();
          op1_max = OP1_MAX_RANGE();
          op2_max = OP2_MAX_RANGE();
          if (!zend_abs_range(op2_min, op2_max, &op2_abs_min, &op2_abs_max)) {
            break;
          }

          if (op2_abs_max == 0) {
            /* Always modulus by zero, nothing we can do */
            break;
          }
          if (op2_abs_min == 0) {
            /* Ignore the modulus by zero case, which will throw */
            op2_abs_min++;
          }

          if (op1_min >= 0) {
            tmp->min = op1_max < op2_abs_min ? op1_min : 0;
            tmp->max = MIN(op1_max, op2_abs_max - 1);
          } else if (op1_max <= 0) {
            tmp->min = MAX(op1_min, -op2_abs_max + 1);
            tmp->max = op1_min > -op2_abs_min ? op1_max : 0;
          } else {
            tmp->min = MAX(op1_min, -op2_abs_max + 1);
            tmp->max = MIN(op1_max, op2_abs_max - 1);
          }
        }
        return 1;
      }
      break;
    case ZEND_SL:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW() ||
          OP2_RANGE_OVERFLOW()) {
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          op1_min = OP1_MIN_RANGE();
          op2_min = OP2_MIN_RANGE();
          op1_max = OP1_MAX_RANGE();
          op2_max = OP2_MAX_RANGE();

          /* Shifts by negative numbers will throw, ignore them */
          if (op2_min < 0) {
            op2_min = 0;
          }
          if (op2_max < 0) {
            op2_max = 0;
          }

          if (shift_left_overflows(op1_min, op2_max)
              || shift_left_overflows(op1_max, op2_max)) {
            tmp->min = ZEND_LONG_MIN;
            tmp->max = ZEND_LONG_MAX;
          } else {
            t1 = safe_shift_left(op1_min, op2_min);
            t2 = safe_shift_left(op1_min, op2_max);
            t3 = safe_shift_left(op1_max, op2_min);
            t4 = safe_shift_left(op1_max, op2_max);
            tmp->min = MIN(MIN(t1, t2), MIN(t3, t4));
            tmp->max = MAX(MAX(t1, t2), MAX(t3, t4));
          }
        }
        return 1;
      }
      break;
    case ZEND_SR:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW() ||
          OP2_RANGE_OVERFLOW()) {
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          op1_min = OP1_MIN_RANGE();
          op2_min = OP2_MIN_RANGE();
          op1_max = OP1_MAX_RANGE();
          op2_max = OP2_MAX_RANGE();

          /* Shifts by negative numbers will throw, ignore them */
          if (op2_min < 0) {
            op2_min = 0;
          }
          if (op2_max < 0) {
            op2_max = 0;
          }

          /* Shifts by more than the integer size will be 0 or -1 */
          if (op2_min >= SIZEOF_ZEND_LONG * 8) {
            op2_min = SIZEOF_ZEND_LONG * 8 - 1;
          }
          if (op2_max >= SIZEOF_ZEND_LONG * 8) {
            op2_max = SIZEOF_ZEND_LONG * 8 - 1;
          }

          t1 = op1_min >> op2_min;
          t2 = op1_min >> op2_max;
          t3 = op1_max >> op2_min;
          t4 = op1_max >> op2_max;
          tmp->min = MIN(MIN(t1, t2), MIN(t3, t4));
          tmp->max = MAX(MAX(t1, t2), MAX(t3, t4));
        }
        return 1;
      }
      break;
    case ZEND_BW_OR:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW() ||
          OP2_RANGE_OVERFLOW()) {
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          op1_min = OP1_MIN_RANGE();
          op2_min = OP2_MIN_RANGE();
          op1_max = OP1_MAX_RANGE();
          op2_max = OP2_MAX_RANGE();
          zend_ssa_range_or(op1_min, op1_max, op2_min, op2_max, tmp);
        }
        return 1;
      }
      break;
    case ZEND_BW_AND:
      if (OP1_HAS_RANGE() && OP2_HAS_RANGE()) {
        if (OP1_RANGE_UNDERFLOW() ||
          OP2_RANGE_UNDERFLOW() ||
          OP1_RANGE_OVERFLOW() ||
          OP2_RANGE_OVERFLOW()) {
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
        } else {
          op1_min = OP1_MIN_RANGE();
          op2_min = OP2_MIN_RANGE();
          op1_max = OP1_MAX_RANGE();
          op2_max = OP2_MAX_RANGE();
          zend_ssa_range_and(op1_min, op1_max, op2_min, op2_max, tmp);
        }
        return 1;
      }
      break;
    case ZEND_BW_XOR:
      // TODO
      break;
    default: ZEND_UNREACHABLE();
  }
  return 0;
}

static bool zend_inference_calc_range(const zend_op_array *op_array, const zend_ssa *ssa, int var, int widening, bool narrowing, zend_ssa_range *tmp)
{
  uint32_t line;
  const zend_op *opline;
  const zend_ssa_op *ssa_op;

  if (ssa->vars[var].definition_phi) {
    const zend_ssa_phi *p = ssa->vars[var].definition_phi;

    tmp->underflow = 0;
    tmp->min = ZEND_LONG_MAX;
    tmp->max = ZEND_LONG_MIN;
    tmp->overflow = 0;
    if (p->pi >= 0 && p->has_range_constraint) {
      const zend_ssa_range_constraint *constraint = &p->constraint.range;
      if (constraint->negative) {
        int src1 = p->sources[0];

        if (ssa->var_info[src1].has_range) {
          *tmp = ssa->var_info[src1].range;
          if (constraint->range.min == constraint->range.max
           && !constraint->range.underflow
           && !constraint->range.overflow
           && p->constraint.range.min_ssa_var < 0
           && p->constraint.range.max_ssa_var < 0
           && ssa->vars[src1].definition >= 0) {
            /* Check for constrained induction variable */
            line = ssa->vars[src1].definition;
            opline = op_array->opcodes + line;
            switch (opline->opcode) {
              case ZEND_PRE_DEC:
              case ZEND_POST_DEC:
                if (!tmp->underflow) {
                  const zend_ssa_phi *p = ssa->vars[ssa->ops[line].op1_use].definition_phi;

                  if (p && p->pi < 0
                   && ssa->cfg.blocks[p->block].predecessors_count == 2
                   && p->sources[1] == var
                   && ssa->var_info[p->sources[0]].has_range
                   && ssa->var_info[p->sources[0]].range.min > constraint->range.max) {
                    tmp->min = constraint->range.max + 1;
                  }
                }
                break;
              case ZEND_PRE_INC:
              case ZEND_POST_INC:
                if (!tmp->overflow) {
                  const zend_ssa_phi *p = ssa->vars[ssa->ops[line].op1_use].definition_phi;

                  if (p && p->pi < 0
                   && ssa->cfg.blocks[p->block].predecessors_count == 2
                   && p->sources[1] == var
                   && ssa->var_info[p->sources[0]].has_range
                   && ssa->var_info[p->sources[0]].range.max < constraint->range.min) {
                    tmp->max = constraint->range.min - 1;
                  }
                }
                break;
            }
          }
        } else if (narrowing) {
          tmp->underflow = 1;
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
          tmp->overflow = 1;
        }

#ifdef NEG_RANGE
        if (constraint->min_ssa_var < 0 &&
            constraint->max_ssa_var < 0 &&
            ssa->var_info[p->ssa_var].has_range) {
          LOG_NEG_RANGE("%s() #%d [%ld..%ld] -> [%ld..%ld]?\n",
            ZSTR_VAL(op_array->function_name),
            p->ssa_var,
            ssa->var_info[p->ssa_var].range.min,
            ssa->var_info[p->ssa_var].range.max,
            tmp->min,
            tmp->max);
          if (constraint->negative == NEG_USE_LT &&
              tmp->max >= constraint->range.min) {
            tmp->overflow = 0;
            tmp->max = constraint->range.min - 1;
            LOG_NEG_RANGE("  => [%ld..%ld]\n", tmp->min, tmp->max);
          } else if (constraint->negative == NEG_USE_GT &&
                     tmp->min <= constraint->range.max) {
            tmp->underflow = 0;
            tmp->min = constraint->range.max + 1;
            LOG_NEG_RANGE("  => [%ld..%ld]\n", tmp->min, tmp->max);
          }
        }
#endif
      } else if (ssa->var_info[p->sources[0]].has_range) {
        /* intersection */
        *tmp = ssa->var_info[p->sources[0]].range;
        if (constraint->min_ssa_var < 0) {
          tmp->underflow = constraint->range.underflow && tmp->underflow;
          tmp->min = MAX(constraint->range.min, tmp->min);
#ifdef SYM_RANGE
        } else if (narrowing && ssa->var_info[constraint->min_ssa_var].has_range) {
          tmp->underflow = ssa->var_info[constraint->min_ssa_var].range.underflow && tmp->underflow;
          if (!add_will_overflow(ssa->var_info[constraint->min_ssa_var].range.min, constraint->range.min)) {
            tmp->min = MAX(ssa->var_info[constraint->min_ssa_var].range.min + constraint->range.min, tmp->min);
          }
#endif
        }
        if (constraint->max_ssa_var < 0) {
          tmp->max = MIN(constraint->range.max, tmp->max);
          tmp->overflow = constraint->range.overflow && tmp->overflow;
#ifdef SYM_RANGE
        } else if (narrowing && ssa->var_info[constraint->max_ssa_var].has_range) {
          if (!add_will_overflow(ssa->var_info[constraint->max_ssa_var].range.max, constraint->range.max)) {
            tmp->max = MIN(ssa->var_info[constraint->max_ssa_var].range.max + constraint->range.max, tmp->max);
          }
          tmp->overflow = ssa->var_info[constraint->max_ssa_var].range.overflow && tmp->overflow;
#endif
        }
      } else if (narrowing) {
        if (constraint->min_ssa_var < 0) {
          tmp->underflow = constraint->range.underflow;
          tmp->min = constraint->range.min;
#ifdef SYM_RANGE
        } else if (narrowing && ssa->var_info[constraint->min_ssa_var].has_range) {
          if (add_will_overflow(ssa->var_info[constraint->min_ssa_var].range.min, constraint->range.min)) {
            tmp->underflow = 1;
            tmp->min = ZEND_LONG_MIN;
          } else {
            tmp->underflow = ssa->var_info[constraint->min_ssa_var].range.underflow;
            tmp->min = ssa->var_info[constraint->min_ssa_var].range.min + constraint->range.min;
          }
#endif
        } else {
          tmp->underflow = 1;
          tmp->min = ZEND_LONG_MIN;
        }
        if (constraint->max_ssa_var < 0) {
          tmp->max = constraint->range.max;
          tmp->overflow = constraint->range.overflow;
#ifdef SYM_RANGE
        } else if (narrowing && ssa->var_info[constraint->max_ssa_var].has_range) {
          if (add_will_overflow(ssa->var_info[constraint->max_ssa_var].range.max, constraint->range.max)) {
            tmp->overflow = 1;
            tmp->max = ZEND_LONG_MAX;
          } else {
            tmp->max = ssa->var_info[constraint->max_ssa_var].range.max + constraint->range.max;
            tmp->overflow = ssa->var_info[constraint->max_ssa_var].range.overflow;
          }
#endif
        } else {
          tmp->max = ZEND_LONG_MAX;
          tmp->overflow = 1;
        }
      }
    } else {
      for (uint32_t i = 0; i < ssa->cfg.blocks[p->block].predecessors_count; i++) {
        ZEND_ASSERT(p->sources[i] >= 0);
        if (ssa->var_info[p->sources[i]].has_range) {
          /* union */
          tmp->underflow |= ssa->var_info[p->sources[i]].range.underflow;
          tmp->min = MIN(tmp->min, ssa->var_info[p->sources[i]].range.min);
          tmp->max = MAX(tmp->max, ssa->var_info[p->sources[i]].range.max);
          tmp->overflow |= ssa->var_info[p->sources[i]].range.overflow;
        } else if (narrowing) {
          tmp->underflow = 1;
          tmp->min = ZEND_LONG_MIN;
          tmp->max = ZEND_LONG_MAX;
          tmp->overflow = 1;
        }
      }
    }
    return (tmp->min <= tmp->max);
  } else if (ssa->vars[var].definition < 0) {
    return 0;
  }
  line = ssa->vars[var].definition;
  opline = op_array->opcodes + line;
  ssa_op = &ssa->ops[line];

  return zend_inference_propagate_range(op_array, ssa, opline, ssa_op, var, tmp);
}

ZEND_API bool zend_inference_propagate_range(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op* ssa_op, int var, zend_ssa_range *tmp)
{
  tmp->underflow = 0;
  tmp->overflow = 0;
  switch (opline->opcode) {
    case ZEND_ADD:
    case ZEND_SUB:
    case ZEND_MUL:
    case ZEND_DIV:
    case ZEND_MOD:
    case ZEND_SL:
    case ZEND_SR:
    case ZEND_BW_OR:
    case ZEND_BW_AND:
    case ZEND_BW_XOR:
      if (ssa_op->result_def == var) {
        return zend_inference_calc_binary_op_range(
          op_array, ssa, opline, ssa_op, opline->opcode, tmp);
      }
      break;

    case ZEND_BW_NOT:
      if (ssa_op->result_def == var) {
        if (OP1_HAS_RANGE()) {
          if (OP1_RANGE_UNDERFLOW() ||
              OP1_RANGE_OVERFLOW()) {
            tmp->min = ZEND_LONG_MIN;
            tmp->max = ZEND_LONG_MAX;
          } else {
            zend_long op1_min = OP1_MIN_RANGE();
            zend_long op1_max = OP1_MAX_RANGE();
            tmp->min = ~op1_max;
            tmp->max = ~op1_min;
          }
          return 1;
        }
      }
      break;
    case ZEND_CAST:
      if (ssa_op->op1_def == var) {
        if (ssa_op->op1_def >= 0) {
          if (OP1_HAS_RANGE()) {
            tmp->underflow = OP1_RANGE_UNDERFLOW();
            tmp->min = OP1_MIN_RANGE();
            tmp->max = OP1_MAX_RANGE();
            tmp->overflow  = OP1_RANGE_OVERFLOW();
            return 1;
          }
        }
      } else if (ssa_op->result_def == var) {
        if (opline->extended_value == IS_LONG) {
          if (OP1_HAS_RANGE()) {
            tmp->min = OP1_MIN_RANGE();
            tmp->max = OP1_MAX_RANGE();
            return 1;
          } else {
            tmp->min = ZEND_LONG_MIN;
            tmp->max = ZEND_LONG_MAX;
            return 1;
          }
        }
      }
      break;
    case ZEND_QM_ASSIGN:
    case ZEND_JMP_SET:
    case ZEND_COALESCE:
    case ZEND_COPY_TMP:
      if (ssa_op->op1_def == var) {
        if (ssa_op->op1_def >= 0) {
          if (OP1_HAS_RANGE()) {
            tmp->underflow = OP1_RANGE_UNDERFLOW();
            tmp->min = OP1_MIN_RANGE();
            tmp->max = OP1_MAX_RANGE();
            tmp->overflow  = OP1_RANGE_OVERFLOW();
            return 1;
          }
        }
      }
      if (ssa_op->result_def == var) {
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow  = OP1_RANGE_OVERFLOW();
          return 1;
        }
      }
      break;
    case ZEND_SEND_VAR:
      if (ssa_op->op1_def == var) {
        if (ssa_op->op1_def >= 0) {
          if (OP1_HAS_RANGE()) {
            tmp->underflow = OP1_RANGE_UNDERFLOW();
            tmp->min = OP1_MIN_RANGE();
            tmp->max = OP1_MAX_RANGE();
            tmp->overflow  = OP1_RANGE_OVERFLOW();
            return 1;
          }
        }
      }
      break;
    case ZEND_PRE_INC:
      if (ssa_op->op1_def == var || ssa_op->result_def == var) {
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow = OP1_RANGE_OVERFLOW();
          if (tmp->max < ZEND_LONG_MAX) {
            tmp->max++;
          } else {
            tmp->overflow = 1;
          }
          if (tmp->min < ZEND_LONG_MAX && !tmp->underflow) {
            tmp->min++;
          }
          return 1;
        }
      }
      break;
    case ZEND_PRE_DEC:
      if (ssa_op->op1_def == var || ssa_op->result_def == var) {
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow = OP1_RANGE_OVERFLOW();
          if (tmp->min > ZEND_LONG_MIN) {
            tmp->min--;
          } else {
            tmp->underflow = 1;
          }
          if (tmp->max > ZEND_LONG_MIN && !tmp->overflow) {
            tmp->max--;
          }
          return 1;
        }
      }
      break;
    case ZEND_POST_INC:
      if (ssa_op->op1_def == var || ssa_op->result_def == var) {
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow = OP1_RANGE_OVERFLOW();
          if (ssa_op->result_def == var) {
            return 1;
          }
          if (tmp->max < ZEND_LONG_MAX) {
            tmp->max++;
          } else {
            tmp->overflow = 1;
          }
          if (tmp->min < ZEND_LONG_MAX && !tmp->underflow) {
            tmp->min++;
          }
          return 1;
        }
      }
      break;
    case ZEND_POST_DEC:
      if (ssa_op->op1_def == var || ssa_op->result_def == var) {
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow = OP1_RANGE_OVERFLOW();
          if (ssa_op->result_def == var) {
            return 1;
          }
          if (tmp->min > ZEND_LONG_MIN) {
            tmp->min--;
          } else {
            tmp->underflow = 1;
          }
          if (tmp->max > ZEND_LONG_MIN && !tmp->overflow) {
            tmp->max--;
          }
          return 1;
        }
      }
      break;
    case ZEND_UNSET_DIM:
    case ZEND_UNSET_OBJ:
      if (ssa_op->op1_def == var) {
        /* If op1 is scalar, UNSET_DIM and UNSET_OBJ have no effect, so we can keep
         * the previous ranges. */
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow  = OP1_RANGE_OVERFLOW();
          return 1;
        }
      }
      break;
    case ZEND_ASSIGN:
      if (ssa_op->op1_def == var || ssa_op->op2_def == var || ssa_op->result_def == var) {
        if (OP2_HAS_RANGE()) {
          tmp->min = OP2_MIN_RANGE();
          tmp->max = OP2_MAX_RANGE();
          tmp->underflow = OP2_RANGE_UNDERFLOW();
          tmp->overflow  = OP2_RANGE_OVERFLOW();
          return 1;
        }
      }
      break;
    case ZEND_ASSIGN_DIM:
    case ZEND_ASSIGN_OBJ:
    case ZEND_ASSIGN_STATIC_PROP:
    case ZEND_ASSIGN_DIM_OP:
    case ZEND_ASSIGN_OBJ_OP:
    case ZEND_ASSIGN_STATIC_PROP_OP:
      if ((ssa_op+1)->op1_def == var) {
        opline++;
        ssa_op++;
        if (OP1_HAS_RANGE()) {
          tmp->min = OP1_MIN_RANGE();
          tmp->max = OP1_MAX_RANGE();
          tmp->underflow = OP1_RANGE_UNDERFLOW();
          tmp->overflow  = OP1_RANGE_OVERFLOW();
        }
        return 1;
      }
      break;
    case ZEND_ASSIGN_OP:
      if (opline->extended_value != ZEND_CONCAT
       && opline->extended_value != ZEND_POW) {
        if (ssa_op->op1_def == var || ssa_op->result_def == var) {
          return zend_inference_calc_binary_op_range(
            op_array, ssa, opline, ssa_op,
            opline->extended_value, tmp);
        }
      }
      break;
    case ZEND_OP_DATA:
      if (ssa_op->op1_def == var) {
        if ((opline-1)->opcode == ZEND_ASSIGN_DIM ||
            (opline-1)->opcode == ZEND_ASSIGN_OBJ ||
            (opline-1)->opcode == ZEND_ASSIGN_STATIC_PROP ||
            (opline-1)->opcode == ZEND_ASSIGN_DIM_OP ||
            (opline-1)->opcode == ZEND_ASSIGN_OBJ_OP ||
            (opline-1)->opcode == ZEND_ASSIGN_STATIC_PROP_OP) {
          if (OP1_HAS_RANGE()) {
            tmp->min = OP1_MIN_RANGE();
            tmp->max = OP1_MAX_RANGE();
            tmp->underflow = OP1_RANGE_UNDERFLOW();
            tmp->overflow  = OP1_RANGE_OVERFLOW();
            return 1;
          }
        }
        break;
      }
      break;
    case ZEND_RECV:
    case ZEND_RECV_INIT:
      if (ssa_op->result_def == var) {
        if (op_array->arg_info &&
            opline->op1.num <= op_array->num_args) {
          zend_type type = op_array->arg_info[opline->op1.num-1].type;
          uint32_t mask = ZEND_TYPE_PURE_MASK_WITHOUT_NULL(type);
          if (mask == MAY_BE_LONG) {
            tmp->underflow = 0;
            tmp->min = ZEND_LONG_MIN;
            tmp->max = ZEND_LONG_MAX;
            tmp->overflow = 0;
            return 1;
          }
        }
      }
      break;
    case ZEND_STRLEN:
      if (ssa_op->result_def == var) {
#if SIZEOF_ZEND_LONG == 4
        /* The length of a string is a non-negative integer. However, on 32-bit
         * platforms overflows into negative lengths may occur, so it's better
         * to not assume any particular range. */
        tmp->min = ZEND_LONG_MIN;
#else
        tmp->min = 0;
#endif
        tmp->max = ZEND_LONG_MAX;
        return 1;
      }
      break;
    case ZEND_FUNC_NUM_ARGS:
      tmp->min = 0;
      tmp->max = ZEND_LONG_MAX;
      return 1;
    case ZEND_COUNT:
      /* count() on Countable objects may return negative numbers */
      tmp->min = ZEND_LONG_MIN;
      tmp->max = ZEND_LONG_MAX;
      return 1;
    case ZEND_DO_FCALL:
    case ZEND_DO_ICALL:
    case ZEND_DO_UCALL:
    case ZEND_DO_FCALL_BY_NAME:
      if (ssa_op->result_def == var) {
        const zend_func_info *func_info = ZEND_FUNC_INFO(op_array);
        const zend_call_info *call_info;
        if (!func_info || !func_info->call_map) {
          break;
        }

        call_info = func_info->call_map[opline - op_array->opcodes];
        if (!call_info || call_info->is_prototype) {
          break;
        }
        if (call_info->callee_func->type == ZEND_USER_FUNCTION) {
          func_info = ZEND_FUNC_INFO(&call_info->callee_func->op_array);
          if (func_info && func_info->return_info.has_range) {
            *tmp = func_info->return_info.range;
            return 1;
          }
        }
//TODO: we can't use type inference for internal functions at this point ???
#if 0
          uint32_t type;

          type = zend_get_func_info(call_info, ssa);
          if (!(type & (MAY_BE_ANY - (MAY_BE_NULL|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_LONG)))) {
            tmp->underflow = 0;
            tmp->min = 0;
            tmp->max = 0;
            tmp->overflow = 0;
            if (type & MAY_BE_LONG) {
              tmp->min = ZEND_LONG_MIN;
              tmp->max = ZEND_LONG_MAX;
            } else if (type & MAY_BE_TRUE) {
              if (!(type & (MAY_BE_NULL|MAY_BE_FALSE))) {
                tmp->min = 1;
              }
              tmp->max = 1;
            }
            return 1;
          }
#endif
      }
      break;
    // FIXME: support for more opcodes
    default:
      break;
  }
  return 0;
}

static void zend_inference_init_range(const zend_op_array *op_array, const zend_ssa *ssa, int var, bool underflow, zend_long min, zend_long max, bool overflow)
{
  if (underflow) {
    min = ZEND_LONG_MIN;
  }
  if (overflow) {
    max = ZEND_LONG_MAX;
  }
  ssa->var_info[var].has_range = 1;
  ssa->var_info[var].range.underflow = underflow;
  ssa->var_info[var].range.min = min;
  ssa->var_info[var].range.max = max;
  ssa->var_info[var].range.overflow = overflow;
  LOG_SSA_RANGE("  change range (init      SCC %2d) %2d [%s%ld..%ld%s]\n", ssa->vars[var].scc, var, (underflow?"-- ":""), min, max, (overflow?" ++":""));
}

static bool zend_inference_widening_meet(zend_ssa_var_info *var_info, zend_ssa_range *r)
{
  if (!var_info->has_range) {
    var_info->has_range = 1;
  } else {
    if (r->underflow ||
        var_info->range.underflow ||
        r->min < var_info->range.min) {
      r->underflow = 1;
      r->min = ZEND_LONG_MIN;
    } else {
      r->min = var_info->range.min;
    }
    if (r->overflow ||
        var_info->range.overflow ||
        r->max > var_info->range.max) {
      r->overflow = 1;
      r->max = ZEND_LONG_MAX;
    } else {
      r->max = var_info->range.max;
    }
    if (var_info->range.min == r->min &&
        var_info->range.max == r->max &&
        var_info->range.underflow == r->underflow &&
        var_info->range.overflow == r->overflow) {
      return 0;
    }
  }
  var_info->range = *r;
  return 1;
}

static bool zend_ssa_range_widening(const zend_op_array *op_array, const zend_ssa *ssa, int var, int scc)
{
  zend_ssa_range tmp;

  if (zend_inference_calc_range(op_array, ssa, var, 1, 0, &tmp)) {
    if (zend_inference_widening_meet(&ssa->var_info[var], &tmp)) {
      LOG_SSA_RANGE("  change range (widening  SCC %2d) %2d [%s%ld..%ld%s]\n", scc, var, (tmp.underflow?"-- ":""), tmp.min, tmp.max, (tmp.overflow?" ++":""));
      return 1;
    }
  }
  return 0;
}

static bool zend_inference_narrowing_meet(zend_ssa_var_info *var_info, zend_ssa_range *r)
{
  if (!var_info->has_range) {
    var_info->has_range = 1;
  } else {
    if (!r->underflow &&
        !var_info->range.underflow &&
        var_info->range.min < r->min) {
      r->min = var_info->range.min;
    }
    if (!r->overflow &&
        !var_info->range.overflow &&
        var_info->range.max > r->max) {
      r->max = var_info->range.max;
    }
    if (r->underflow) {
      r->min = ZEND_LONG_MIN;
    }
    if (r->overflow) {
      r->max = ZEND_LONG_MAX;
    }
    if (var_info->range.min == r->min &&
        var_info->range.max == r->max &&
        var_info->range.underflow == r->underflow &&
        var_info->range.overflow == r->overflow) {
      return 0;
    }
  }
  var_info->range = *r;
  return 1;
}

static bool zend_ssa_range_narrowing(const zend_op_array *op_array, const zend_ssa *ssa, int var, int scc)
{
  zend_ssa_range tmp;

  if (zend_inference_calc_range(op_array, ssa, var, 0, 1, &tmp)) {
    if (zend_inference_narrowing_meet(&ssa->var_info[var], &tmp)) {
      LOG_SSA_RANGE("  change range (narrowing SCC %2d) %2d [%s%ld..%ld%s]\n", scc, var, (tmp.underflow?"-- ":""), tmp.min, tmp.max, (tmp.overflow?" ++":""));
      return 1;
    }
  }
  return 0;
}

#ifdef NEG_RANGE
# define CHECK_INNER_CYCLE(var2) \
  do { \
    if (ssa->vars[var2].scc == ssa->vars[var].scc && \
        !ssa->vars[var2].scc_entry && \
        !zend_bitset_in(visited, var2) && \
      zend_check_inner_cycles(op_array, ssa, worklist, visited, var2)) { \
      return 1; \
    } \
  } while (0)

static bool zend_check_inner_cycles(const zend_op_array *op_array, zend_ssa *ssa, zend_bitset worklist, zend_bitset visited, int var)
{
  if (zend_bitset_in(worklist, var)) {
    return 1;
  }
  zend_bitset_incl(worklist, var);
  FOR_EACH_VAR_USAGE(var, CHECK_INNER_CYCLE);
  zend_bitset_incl(visited, var);
  return 0;
}
#endif

static void zend_infer_ranges_warmup(const zend_op_array *op_array, zend_ssa *ssa, const int *scc_var, const int *next_scc_var, int scc)
{
  int worklist_len = zend_bitset_len(ssa->vars_count);
  int j, n;
  zend_ssa_range tmp;
  ALLOCA_FLAG(use_heap)
  zend_bitset worklist = do_alloca(sizeof(zend_ulong) * worklist_len * 2, use_heap);
  zend_bitset visited = worklist + worklist_len;
#ifdef NEG_RANGE
  bool has_inner_cycles = false;

  memset(worklist, 0, sizeof(zend_ulong) * worklist_len);
  memset(visited, 0, sizeof(zend_ulong) * worklist_len);
  j = scc_var[scc];
  while (j >= 0) {
    if (!zend_bitset_in(visited, j) &&
        zend_check_inner_cycles(op_array, ssa, worklist, visited, j)) {
      has_inner_cycles = true;
      break;
    }
    j = next_scc_var[j];
  }
#endif

  memset(worklist, 0, sizeof(zend_ulong) * worklist_len);

  for (n = 0; n < RANGE_WARMUP_PASSES; n++) {
    j= scc_var[scc];
    while (j >= 0) {
      if (ssa->vars[j].scc_entry
       && !(ssa->var_info[j].type & MAY_BE_REF)) {
        zend_bitset_incl(worklist, j);
      }
      j = next_scc_var[j];
    }

    memset(visited, 0, sizeof(zend_ulong) * worklist_len);

    WHILE_WORKLIST(worklist, worklist_len, j) {
      if (zend_inference_calc_range(op_array, ssa, j, 0, 0, &tmp)) {
#ifdef NEG_RANGE
        if (!has_inner_cycles &&
            ssa->var_info[j].has_range &&
            ssa->vars[j].definition_phi &&
            ssa->vars[j].definition_phi->pi >= 0 &&
          ssa->vars[j].definition_phi->has_range_constraint &&
            ssa->vars[j].definition_phi->constraint.range.negative &&
            ssa->vars[j].definition_phi->constraint.range.min_ssa_var < 0 &&
            ssa->vars[j].definition_phi->constraint.range.max_ssa_var < 0) {
          zend_ssa_range_constraint *constraint =
            &ssa->vars[j].definition_phi->constraint.range;
          if (tmp.min == ssa->var_info[j].range.min &&
              tmp.max == ssa->var_info[j].range.max) {
            if (constraint->negative == NEG_INIT) {
              LOG_NEG_RANGE("#%d INVARIANT\n", j);
              constraint->negative = NEG_INVARIANT;
            }
          } else if (tmp.min == ssa->var_info[j].range.min &&
                     tmp.max == ssa->var_info[j].range.max + 1 &&
                     tmp.max < constraint->range.min) {
            if (constraint->negative == NEG_INIT ||
                constraint->negative == NEG_INVARIANT) {
              LOG_NEG_RANGE("#%d LT\n", j);
              constraint->negative = NEG_USE_LT;
//???NEG
            } else if (constraint->negative == NEG_USE_GT) {
              LOG_NEG_RANGE("#%d UNKNOWN\n", j);
              constraint->negative = NEG_UNKNOWN;
            }
          } else if (tmp.max == ssa->var_info[j].range.max &&
                       tmp.min == ssa->var_info[j].range.min - 1 &&
                     tmp.min > constraint->range.max) {
            if (constraint->negative == NEG_INIT ||
                constraint->negative == NEG_INVARIANT) {
              LOG_NEG_RANGE("#%d GT\n", j);
              constraint->negative = NEG_USE_GT;
//???NEG
            } else if (constraint->negative == NEG_USE_LT) {
              LOG_NEG_RANGE("#%d UNKNOWN\n", j);
              constraint->negative = NEG_UNKNOWN;
            }
          } else {
            LOG_NEG_RANGE("#%d UNKNOWN\n", j);
            constraint->negative = NEG_UNKNOWN;
          }
        }
#endif
        if (zend_inference_narrowing_meet(&ssa->var_info[j], &tmp)) {
          LOG_SSA_RANGE("  change range (warmup %2d SCC %2d) %2d [%s%ld..%ld%s]\n", n, scc, j, (tmp.underflow?"-- ":""), tmp.min, tmp.max, (tmp.overflow?" ++":""));
          zend_bitset_incl(visited, j);
          FOR_EACH_VAR_USAGE(j, ADD_SCC_VAR_1);
        }
      }
    } WHILE_WORKLIST_END();
  }
  free_alloca(worklist, use_heap);
}

static void zend_infer_ranges(const zend_op_array *op_array, zend_ssa *ssa) /* {{{ */
{
  int worklist_len = zend_bitset_len(ssa->vars_count);
  zend_bitset worklist;
  int *next_scc_var;
  int *scc_var;
  zend_ssa_phi *p;
  zend_ssa_range tmp;
  int scc, j;
  ALLOCA_FLAG(use_heap);

  worklist = do_alloca(
    ZEND_MM_ALIGNED_SIZE(sizeof(zend_ulong) * worklist_len) +
    ZEND_MM_ALIGNED_SIZE(sizeof(int) * ssa->vars_count) +
    sizeof(int) * ssa->sccs, use_heap);
  next_scc_var = (int*)((char*)worklist + ZEND_MM_ALIGNED_SIZE(sizeof(zend_ulong) * worklist_len));
  scc_var = (int*)((char*)next_scc_var + ZEND_MM_ALIGNED_SIZE(sizeof(int) * ssa->vars_count));

  LOG_SSA_RANGE("Range Inference\n");

  /* Create linked lists of SSA variables for each SCC */
  memset(scc_var, -1, sizeof(int) * ssa->sccs);
  for (j = 0; j < ssa->vars_count; j++) {
    if (ssa->vars[j].scc >= 0) {
      next_scc_var[j] = scc_var[ssa->vars[j].scc];
      scc_var[ssa->vars[j].scc] = j;
    }
  }

  for (scc = 0; scc < ssa->sccs; scc++) {
    j = scc_var[scc];
    if (next_scc_var[j] < 0) {
      /* SCC with a single element */
      if (ssa->var_info[j].type & MAY_BE_REF) {
        /* pass */
      } else if (zend_inference_calc_range(op_array, ssa, j, 0, 1, &tmp)) {
        zend_inference_init_range(op_array, ssa, j, tmp.underflow, tmp.min, tmp.max, tmp.overflow);
      } else {
        zend_inference_init_range(op_array, ssa, j, true, ZEND_LONG_MIN, ZEND_LONG_MAX, true);
      }
    } else {
      /* Find SCC entry points */
      memset(worklist, 0, sizeof(zend_ulong) * worklist_len);
      do {
        if (ssa->vars[j].scc_entry
         && !(ssa->var_info[j].type & MAY_BE_REF)) {
          zend_bitset_incl(worklist, j);
        }
        j = next_scc_var[j];
      } while (j >= 0);

#if RANGE_WARMUP_PASSES > 0
      zend_infer_ranges_warmup(op_array, ssa, scc_var, next_scc_var, scc);
      j = scc_var[scc];
      do {
        if (!(ssa->var_info[j].type & MAY_BE_REF)) {
          zend_bitset_incl(worklist, j);
        }
        j = next_scc_var[j];
      } while (j >= 0);
#endif

      /* widening */
      WHILE_WORKLIST(worklist, worklist_len, j) {
        if (zend_ssa_range_widening(op_array, ssa, j, scc)) {
          FOR_EACH_VAR_USAGE(j, ADD_SCC_VAR);
        }
      } WHILE_WORKLIST_END();

      /* initialize missing ranges */
      for (j = scc_var[scc]; j >= 0; j = next_scc_var[j]) {
        if (!ssa->var_info[j].has_range
         && !(ssa->var_info[j].type & MAY_BE_REF)) {
          zend_inference_init_range(op_array, ssa, j, true, ZEND_LONG_MIN, ZEND_LONG_MAX,
                  true);
          FOR_EACH_VAR_USAGE(j, ADD_SCC_VAR);
        }
      }

      /* widening (second round) */
      WHILE_WORKLIST(worklist, worklist_len, j) {
        if (zend_ssa_range_widening(op_array, ssa, j, scc)) {
          FOR_EACH_VAR_USAGE(j, ADD_SCC_VAR);
        }
      } WHILE_WORKLIST_END();

      /* Add all SCC entry variables into worklist for narrowing */
      for (j = scc_var[scc]; j >= 0; j = next_scc_var[j]) {
        if (ssa->vars[j].definition_phi
         && ssa->vars[j].definition_phi->pi < 0
         && !(ssa->var_info[j].type & MAY_BE_REF)) {
          /* narrowing Phi functions first */
          zend_ssa_range_narrowing(op_array, ssa, j, scc);
        }
        zend_bitset_incl(worklist, j);
      }

      /* narrowing */
      WHILE_WORKLIST(worklist, worklist_len, j) {
        if (zend_ssa_range_narrowing(op_array, ssa, j, scc)) {
          FOR_EACH_VAR_USAGE(j, ADD_SCC_VAR);
#ifdef SYM_RANGE
          /* Process symbolic control-flow constraints */
          p = ssa->vars[j].sym_use_chain;
          while (p) {
            ADD_SCC_VAR(p->ssa_var);
            p = p->sym_use_chain;
          }
#endif
        }
      } WHILE_WORKLIST_END();
    }
  }

  free_alloca(worklist, use_heap);
}
/* }}} */

static uint32_t get_ssa_alias_types(zend_ssa_alias_kind alias) {
  if (alias == HTTP_RESPONSE_HEADER_ALIAS) {
    return MAY_BE_ARRAY | MAY_BE_ARRAY_KEY_LONG | MAY_BE_ARRAY_OF_STRING | MAY_BE_RC1 | MAY_BE_RCN;
  } else {
    return MAY_BE_UNDEF | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_REF | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
  }
}

#define UPDATE_SSA_TYPE(_type, _var)                  \
  do {                               \
    uint32_t __type = (_type) & ~MAY_BE_GUARD;           \
    int __var = (_var);                       \
    if (__type & MAY_BE_REF) {                   \
      __type |= MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF; \
    }                                \
    if (__var >= 0) {                       \
      zend_ssa_var *__ssa_var = &ssa_vars[__var];         \
      if (__ssa_var->var < op_array->num_args) {         \
        if (__type & MAY_BE_RC1) {                              \
          /* TODO: may be captured by exception backtreace */ \
          __type |= MAY_BE_RCN;                               \
        }                                                       \
      }                                                           \
      if (__ssa_var->var < op_array->last_var) {         \
        if (__type & (MAY_BE_REF|MAY_BE_RCN)) {         \
          __type |= MAY_BE_RC1 | MAY_BE_RCN;         \
        }                            \
        if ((__type & MAY_BE_RC1) && (__type & MAY_BE_STRING)) {\
          /* TODO: support for array keys and ($str . "")*/   \
          __type |= MAY_BE_RCN;                               \
        }                                                       \
        if ((__type & MAY_BE_RC1) && (__type & MAY_BE_OBJECT)) {\
          /* TODO: object may be captured by magic handlers */\
          __type |= MAY_BE_RCN;                               \
        }                                                       \
        if (__ssa_var->alias) {                 \
          __type |= get_ssa_alias_types(__ssa_var->alias);  \
        }                            \
      }                              \
      if (ssa_var_info[__var].type != __type) {           \
        ZEND_ASSERT(ssa_opcodes != NULL ||           \
          __ssa_var->var >= op_array->last_var ||       \
          (ssa_var_info[__var].type & MAY_BE_REF)       \
            == (__type & MAY_BE_REF));            \
        if (ssa_var_info[__var].type & ~__type) {       \
          emit_type_narrowing_warning(op_array, ssa, __var);  \
          return FAILURE;                   \
        }                            \
        ssa_var_info[__var].type = __type;            \
        if (update_worklist) {                   \
          add_usages(op_array, ssa, worklist, __var);     \
        }                            \
      }                              \
      /*zend_bitset_excl(worklist, var);*/            \
    }                                \
  } while (0)

#define UPDATE_SSA_OBJ_TYPE(_ce, _is_instanceof, var)           \
  do {                                                                \
    if (var >= 0) {                         \
      zend_class_entry *__ce = (_ce);               \
      bool __is_instanceof = (_is_instanceof);          \
      if (__ce && (__ce->ce_flags & ZEND_ACC_FINAL)) {     \
        __is_instanceof = false;                \
      }                              \
      if (ssa_var_info[var].ce != __ce ||             \
          ssa_var_info[var].is_instanceof != __is_instanceof) { \
        ssa_var_info[var].ce = __ce;              \
        ssa_var_info[var].is_instanceof = __is_instanceof;    \
        if (update_worklist) {                   \
          add_usages(op_array, ssa, worklist, var);     \
        }                            \
      }                              \
      /*zend_bitset_excl(worklist, var);*/            \
    }                               \
  } while (0)

#define COPY_SSA_OBJ_TYPE(from_var, to_var) do { \
  if ((from_var) >= 0 && (ssa_var_info[(from_var)].type & MAY_BE_OBJECT) \
      && ssa_var_info[(from_var)].ce && !(ssa_var_info[(to_var)].type & MAY_BE_REF)) { \
    UPDATE_SSA_OBJ_TYPE(ssa_var_info[(from_var)].ce, \
      ssa_var_info[(from_var)].is_instanceof, (to_var)); \
  } else { \
    UPDATE_SSA_OBJ_TYPE(NULL, 0, (to_var)); \
  } \
} while (0)

static void add_usages(const zend_op_array *op_array, const zend_ssa *ssa, zend_bitset worklist, int var)
{
  if (ssa->vars[var].phi_use_chain) {
    const zend_ssa_phi *p = ssa->vars[var].phi_use_chain;
    do {
      zend_bitset_incl(worklist, p->ssa_var);
      p = zend_ssa_next_use_phi(ssa, var, p);
    } while (p);
  }
  if (ssa->vars[var].use_chain >= 0) {
    int use = ssa->vars[var].use_chain;
    const zend_ssa_op *op;

    do {
      op = ssa->ops + use;
      if (op->result_def >= 0) {
        zend_bitset_incl(worklist, op->result_def);
      }
      if (op->op1_def >= 0) {
        zend_bitset_incl(worklist, op->op1_def);
      }
      if (op->op2_def >= 0) {
        zend_bitset_incl(worklist, op->op2_def);
      }
      if (op_array->opcodes[use].opcode == ZEND_OP_DATA) {
        op--;
        if (op->result_def >= 0) {
          zend_bitset_incl(worklist, op->result_def);
        }
        if (op->op1_def >= 0) {
          zend_bitset_incl(worklist, op->op1_def);
        }
        if (op->op2_def >= 0) {
          zend_bitset_incl(worklist, op->op2_def);
        }
      } else if (use + 1 < op_array->last
       && op_array->opcodes[use + 1].opcode == ZEND_OP_DATA) {
        op++;
        if (op->result_def >= 0) {
          zend_bitset_incl(worklist, op->result_def);
        }
        if (op->op1_def >= 0) {
          zend_bitset_incl(worklist, op->op1_def);
        }
        if (op->op2_def >= 0) {
          zend_bitset_incl(worklist, op->op2_def);
        }
      }
      use = zend_ssa_next_use(ssa->ops, var, use);
    } while (use >= 0);
  }
}

static void emit_type_narrowing_warning(const zend_op_array *op_array, const zend_ssa *ssa, int var)
{
  int def_op_num = ssa->vars[var].definition;
  const zend_op *def_opline = def_op_num >= 0 ? &op_array->opcodes[def_op_num] : NULL;
  const char *def_op_name = def_opline ? zend_get_opcode_name(def_opline->opcode) : "PHI";
  uint32_t lineno = def_opline ? def_opline->lineno : 0;
  zend_error_at(
    E_WARNING, op_array->filename, lineno,
    "Narrowing occurred during type inference of %s. Please file a bug report on https://github.com/php/php-src/issues", def_op_name);
#if ZEND_DEBUG
  ZEND_ASSERT(0 && "Narrowing during type inference");
#endif
}

ZEND_API uint32_t ZEND_FASTCALL zend_array_type_info(const zval *zv)
{
  HashTable *ht = Z_ARRVAL_P(zv);
  uint32_t tmp = MAY_BE_ARRAY;
  zend_string *str;
  zval *val;

  if (Z_REFCOUNTED_P(zv)) {
    tmp |= MAY_BE_RC1 | MAY_BE_RCN;
  } else {
    tmp |= MAY_BE_RCN;
  }

  if (zend_hash_num_elements(ht) == 0) {
    tmp |=  MAY_BE_ARRAY_EMPTY;
  } else if (HT_IS_PACKED(ht)) {
    tmp |= MAY_BE_ARRAY_PACKED;
    ZEND_HASH_PACKED_FOREACH_VAL(ht, val) {
      tmp |= 1 << (Z_TYPE_P(val) + MAY_BE_ARRAY_SHIFT);
    } ZEND_HASH_FOREACH_END();
  } else {
    ZEND_HASH_MAP_FOREACH_STR_KEY_VAL(ht, str, val) {
      if (str) {
        tmp |= MAY_BE_ARRAY_STRING_HASH;
      } else {
        tmp |= MAY_BE_ARRAY_NUMERIC_HASH;
      }
      tmp |= 1 << (Z_TYPE_P(val) + MAY_BE_ARRAY_SHIFT);
    } ZEND_HASH_FOREACH_END();
  }
  return tmp;
}


ZEND_API uint32_t zend_array_element_type(uint32_t t1, uint8_t op_type, bool write, bool insert)
{
  uint32_t tmp = 0;

  if (t1 & MAY_BE_OBJECT) {
      if (!write) {
      /* can't be REF  because of ZVAL_COPY_DEREF() usage */
      tmp |= MAY_BE_ANY | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
    } else {
      tmp |= MAY_BE_ANY | MAY_BE_REF | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
      }
    if (write) {
      tmp |= MAY_BE_INDIRECT;
    }
  }
  if (t1 & MAY_BE_ARRAY) {
    if (insert) {
      tmp |= MAY_BE_NULL;
    } else {
      tmp |= MAY_BE_NULL | ((t1 & MAY_BE_ARRAY_OF_ANY) >> MAY_BE_ARRAY_SHIFT);
      if (tmp & MAY_BE_ARRAY) {
        tmp |= MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
      }
      if (tmp & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
        if (!write) {
          /* can't be REF  because of ZVAL_COPY_DEREF() usage */
          tmp |= MAY_BE_RCN;
          if ((op_type & (IS_VAR|IS_TMP_VAR)) && (t1 & MAY_BE_RC1)) {
            tmp |= MAY_BE_RC1;
          }
        } else if (t1 & MAY_BE_ARRAY_OF_REF) {
          tmp |= MAY_BE_REF | MAY_BE_RC1 | MAY_BE_RCN;
        } else {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        }
      }
    }
    if (write) {
      tmp |= MAY_BE_INDIRECT;
    }
  }
  if (t1 & MAY_BE_STRING) {
    tmp |= MAY_BE_STRING | MAY_BE_RC1;
    if (write) {
      tmp |= MAY_BE_NULL;
    }
  }
  if (t1 & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
    tmp |= MAY_BE_NULL;
    if (write) {
      tmp |= MAY_BE_INDIRECT;
    }
  }
  if (t1 & (MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_RESOURCE)) {
    if (!write) {
      tmp |= MAY_BE_NULL;
    }
  }
  return tmp;
}

static uint32_t assign_dim_array_result_type(
    uint32_t arr_type, uint32_t dim_type, uint32_t value_type, uint8_t dim_op_type) {
  uint32_t tmp = 0;
  /* Only add key type if we have a value type. We want to maintain the invariant that a
   * key type exists iff a value type exists even in dead code that may use empty types. */
  if (value_type & (MAY_BE_ANY|MAY_BE_UNDEF)) {
    if (value_type & MAY_BE_UNDEF) {
      value_type |= MAY_BE_NULL;
    }
    if (dim_op_type == IS_UNUSED) {
      if (arr_type & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
        tmp |= MAY_BE_ARRAY_PACKED;
      }
      tmp |= MAY_BE_HASH_ONLY(arr_type) ? MAY_BE_ARRAY_NUMERIC_HASH : MAY_BE_ARRAY_KEY_LONG;
    } else {
      if (dim_type & (MAY_BE_LONG|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_RESOURCE|MAY_BE_DOUBLE)) {
        if (arr_type & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
          tmp |= MAY_BE_ARRAY_PACKED;
        }
        tmp |= MAY_BE_HASH_ONLY(arr_type) ? MAY_BE_ARRAY_NUMERIC_HASH : MAY_BE_ARRAY_KEY_LONG;
      }
      if (dim_type & MAY_BE_STRING) {
        tmp |= MAY_BE_ARRAY_KEY_STRING;
        if (dim_op_type != IS_CONST) {
          // FIXME: numeric string
          if (arr_type & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
            tmp |= MAY_BE_ARRAY_PACKED;
          }
          tmp |= MAY_BE_HASH_ONLY(arr_type) ? MAY_BE_ARRAY_NUMERIC_HASH : MAY_BE_ARRAY_KEY_LONG;
        }
      }
      if (dim_type & (MAY_BE_UNDEF|MAY_BE_NULL)) {
        tmp |= MAY_BE_ARRAY_KEY_STRING;
      }
    }
  }
  /* Only add value type if we have a key type. It might be that the key type is illegal
   * for arrays. */
  if (tmp & MAY_BE_ARRAY_KEY_ANY) {
    tmp |= (value_type & MAY_BE_ANY) << MAY_BE_ARRAY_SHIFT;
  }
  tmp &= ~MAY_BE_ARRAY_EMPTY;
  return tmp;
}

static uint32_t assign_dim_result_type(
    uint32_t arr_type, uint32_t dim_type, uint32_t value_type, uint8_t dim_op_type) {
  uint32_t tmp = arr_type & ~(MAY_BE_RC1|MAY_BE_RCN);

  if (arr_type & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
    tmp &= ~(MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE);
    tmp |= MAY_BE_ARRAY|MAY_BE_RC1;
  }
  if (tmp & (MAY_BE_ARRAY|MAY_BE_STRING)) {
    tmp |= MAY_BE_RC1;
  }
  if (tmp & (MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
    tmp |= MAY_BE_RC1 | MAY_BE_RCN;
  }
  if (tmp & MAY_BE_ARRAY) {
    tmp |= assign_dim_array_result_type(arr_type, dim_type, value_type, dim_op_type);
  }
  return tmp;
}

/* For binary ops that have compound assignment operators */
static uint32_t binary_op_result_type(
    const zend_ssa *ssa, uint8_t opcode, uint32_t t1, uint32_t t2, int result_var,
    zend_long optimization_level) {
  uint32_t tmp = 0;
  uint32_t t1_type = (t1 & MAY_BE_ANY) | (t1 & MAY_BE_UNDEF ? MAY_BE_NULL : 0);
  uint32_t t2_type = (t2 & MAY_BE_ANY) | (t2 & MAY_BE_UNDEF ? MAY_BE_NULL : 0);

  if (!(ZEND_OPTIMIZER_IGNORE_OVERLOADING & optimization_level)) {
    /* Handle potentially overloaded operators.
     * This could be made more precise by checking the class type, if known. */
    if ((t1_type & MAY_BE_OBJECT) || (t2_type & MAY_BE_OBJECT)) {
      /* This is somewhat GMP specific. */
      tmp |= MAY_BE_OBJECT | MAY_BE_FALSE | MAY_BE_RC1;
    }
  }

  switch (opcode) {
    case ZEND_ADD:
      if (t1_type == MAY_BE_LONG && t2_type == MAY_BE_LONG) {
        if (result_var < 0 ||
          !ssa->var_info[result_var].has_range ||
            ssa->var_info[result_var].range.underflow ||
            ssa->var_info[result_var].range.overflow) {
          /* may overflow */
          tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        } else {
          tmp |= MAY_BE_LONG;
        }
      } else if (t1_type == MAY_BE_DOUBLE || t2_type == MAY_BE_DOUBLE) {
        tmp |= MAY_BE_DOUBLE;
      } else if (t1_type == MAY_BE_ARRAY && t2_type == MAY_BE_ARRAY) {
        tmp |= MAY_BE_ARRAY | MAY_BE_RC1;
        tmp |= t1 & (MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF);
        tmp |= t2 & (MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF);
      } else {
        tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        if ((t1_type & MAY_BE_ARRAY) && (t2_type & MAY_BE_ARRAY)) {
          tmp |= MAY_BE_ARRAY | MAY_BE_RC1;
          tmp |= t1 & (MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF);
          tmp |= t2 & (MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF);
        }
      }
      break;
    case ZEND_SUB:
    case ZEND_MUL:
      if (t1_type == MAY_BE_LONG && t2_type == MAY_BE_LONG) {
        if (result_var < 0 ||
          !ssa->var_info[result_var].has_range ||
            ssa->var_info[result_var].range.underflow ||
            ssa->var_info[result_var].range.overflow) {
          /* may overflow */
          tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        } else {
          tmp |= MAY_BE_LONG;
        }
      } else if (t1_type == MAY_BE_DOUBLE || t2_type == MAY_BE_DOUBLE) {
        tmp |= MAY_BE_DOUBLE;
      } else {
        tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
      }
      break;
    case ZEND_DIV:
    case ZEND_POW:
      if (t1_type == MAY_BE_DOUBLE || t2_type == MAY_BE_DOUBLE) {
        tmp |= MAY_BE_DOUBLE;
      } else {
        tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
      }
      /* Division by zero results in Inf/-Inf/Nan (double), so it doesn't need any special
       * handling */
      break;
    case ZEND_MOD:
      tmp |= MAY_BE_LONG;
      /* Division by zero results in an exception, so it doesn't need any special handling */
      break;
    case ZEND_BW_OR:
    case ZEND_BW_AND:
    case ZEND_BW_XOR:
      if ((t1_type & MAY_BE_STRING) && (t2_type & MAY_BE_STRING)) {
        tmp |= MAY_BE_STRING | MAY_BE_RC1 | MAY_BE_RCN;
      }
      if ((t1_type & ~MAY_BE_STRING) || (t2_type & ~MAY_BE_STRING)) {
        tmp |= MAY_BE_LONG;
      }
      break;
    case ZEND_SL:
    case ZEND_SR:
      tmp |= MAY_BE_LONG;
      break;
    case ZEND_CONCAT:
    case ZEND_FAST_CONCAT:
      /* TODO: +MAY_BE_OBJECT ??? */
      tmp = MAY_BE_STRING | MAY_BE_RC1 | MAY_BE_RCN;
      break;
    default: ZEND_UNREACHABLE();
  }
  return tmp;
}

static uint32_t zend_convert_type_declaration_mask(uint32_t type_mask) {
  uint32_t result_mask = type_mask & MAY_BE_ANY;
  if (type_mask & MAY_BE_VOID) {
    result_mask |= MAY_BE_NULL;
  }
  if (type_mask & MAY_BE_CALLABLE) {
    result_mask |= MAY_BE_STRING|MAY_BE_OBJECT|MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF;
  }
  if (type_mask & MAY_BE_STATIC) {
    result_mask |= MAY_BE_OBJECT;
  }
  if (type_mask & MAY_BE_ARRAY) {
    result_mask |= MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF;
  }
  return result_mask;
}

static uint32_t zend_convert_type(const zend_script *script, zend_type type, zend_class_entry **pce)
{
  if (pce) {
    *pce = NULL;
  }

  if (!ZEND_TYPE_IS_SET(type)) {
    return MAY_BE_ANY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF|MAY_BE_RC1|MAY_BE_RCN;
  }

  uint32_t tmp = zend_convert_type_declaration_mask(ZEND_TYPE_PURE_MASK(type));
  if (ZEND_TYPE_IS_COMPLEX(type)) {
    tmp |= MAY_BE_OBJECT;
    if (pce) {
      /* As we only have space to store one CE,
       * we use a plain object type for class unions. */
      if (ZEND_TYPE_HAS_NAME(type)) {
        zend_string *lcname = zend_string_tolower(ZEND_TYPE_NAME(type));
        // TODO: Pass through op_array.
        *pce = zend_optimizer_get_class_entry(script, NULL, lcname);
        zend_string_release_ex(lcname, 0);
      }
    }
  }
  if (tmp & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
    tmp |= MAY_BE_RC1 | MAY_BE_RCN;
  }
  return tmp;
}

ZEND_API uint32_t zend_fetch_arg_info_type(const zend_script *script, const zend_arg_info *arg_info, zend_class_entry **pce)
{
  return zend_convert_type(script, arg_info->type, pce);
}

static const zend_property_info *lookup_prop_info(const zend_class_entry *ce, zend_string *name, zend_class_entry *scope) {
  const zend_property_info *prop_info;

  /* If the class is linked, reuse the precise runtime logic. */
  if ((ce->ce_flags & ZEND_ACC_LINKED)
   && (!scope || (scope->ce_flags & ZEND_ACC_LINKED))) {
    const zend_class_entry *prev_scope = EG(fake_scope);
    EG(fake_scope) = scope;
    prop_info = zend_get_property_info(ce, name, 1);
    EG(fake_scope) = prev_scope;
    if (prop_info && prop_info != ZEND_WRONG_PROPERTY_INFO) {
      return prop_info;
    }
    return NULL;
  }

  /* Otherwise, handle only some safe cases */
  prop_info = zend_hash_find_ptr(&ce->properties_info, name);
  if (prop_info &&
    ((prop_info->ce == scope) ||
     (!scope && (prop_info->flags & ZEND_ACC_PUBLIC)))
  ) {
    return prop_info;
  }
  return NULL;
}

static const zend_property_info *zend_fetch_prop_info(const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline, const zend_ssa_op *ssa_op)
{
  const zend_property_info *prop_info = NULL;
  if (opline->op2_type == IS_CONST) {
    const zend_class_entry *ce = NULL;

    if (opline->op1_type == IS_UNUSED && !(op_array->fn_flags & ZEND_ACC_TRAIT_CLONE)) {
      ce = op_array->scope;
    } else if (ssa_op->op1_use >= 0) {
      ce = ssa->var_info[ssa_op->op1_use].ce;
    }
    if (ce) {
      prop_info = lookup_prop_info(ce,
        Z_STR_P(CRT_CONSTANT(opline->op2)),
        op_array->scope);
      if (prop_info && (prop_info->flags & ZEND_ACC_STATIC)) {
        prop_info = NULL;
      }
    }
  }
  return prop_info;
}

static const zend_property_info *zend_fetch_static_prop_info(const zend_script *script, const zend_op_array *op_array, const zend_ssa *ssa, const zend_op *opline)
{
  const zend_property_info *prop_info = NULL;
  if (opline->op1_type == IS_CONST) {
    const zend_class_entry *ce = NULL;
    if (opline->op2_type == IS_UNUSED) {
      uint32_t fetch_type = opline->op2.num & ZEND_FETCH_CLASS_MASK;
      switch (fetch_type) {
        case ZEND_FETCH_CLASS_SELF:
        case ZEND_FETCH_CLASS_STATIC:
          /* We enforce that static property types cannot change during inheritance, so
           * handling static the same way as self here is legal. */
          ce = op_array->scope;
          break;
        case ZEND_FETCH_CLASS_PARENT:
          if (op_array->scope && (op_array->scope->ce_flags & ZEND_ACC_LINKED)) {
            ce = op_array->scope->parent;
          }
          break;
      }
    } else if (opline->op2_type == IS_CONST) {
      const zval *zv = CRT_CONSTANT(opline->op2);
      ce = zend_optimizer_get_class_entry(script, op_array, Z_STR_P(zv + 1));
    }

    if (ce) {
      const zval *zv = CRT_CONSTANT(opline->op1);
      prop_info = lookup_prop_info(ce, Z_STR_P(zv), op_array->scope);
      if (prop_info && !(prop_info->flags & ZEND_ACC_STATIC)) {
        prop_info = NULL;
      }
    }
  }
  return prop_info;
}

static uint32_t zend_fetch_prop_type(const zend_script *script, const zend_property_info *prop_info, zend_class_entry **pce)
{
  if (!prop_info) {
    if (pce) {
      *pce = NULL;
    }
    return MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_RC1 | MAY_BE_RCN;
  }

  return zend_convert_type(script, prop_info->type, pce);
}

static bool result_may_be_separated(const zend_ssa *ssa, const zend_ssa_op *ssa_op)
{
  int tmp_var = ssa_op->result_def;

  if (ssa->vars[tmp_var].use_chain >= 0
   && !ssa->vars[tmp_var].phi_use_chain) {
    const zend_ssa_op *use_op = &ssa->ops[ssa->vars[tmp_var].use_chain];

    /* TODO: analyze instructions between ssa_op and use_op */
    if (use_op == ssa_op + 1) {
      if ((use_op->op1_use == tmp_var && use_op->op1_use_chain < 0)
       || (use_op->op2_use == tmp_var && use_op->op2_use_chain < 0)) {
        return 0;
      }
    }
  }
  return 1;
}

static zend_always_inline zend_result _zend_update_type_info(
      const zend_op_array *op_array,
      zend_ssa            *ssa,
      const zend_script   *script,
      zend_bitset          worklist,
      const zend_op       *opline,
      zend_ssa_op         *ssa_op,
      const zend_op      **ssa_opcodes,
      zend_long            optimization_level,
      bool            update_worklist)
{
  uint32_t t1, t2;
  uint32_t tmp, orig;
  zend_ssa_var *ssa_vars = ssa->vars;
  zend_ssa_var_info *ssa_var_info = ssa->var_info;
  zend_class_entry *ce;
  int j;

  if (opline->opcode == ZEND_OP_DATA) {
    opline--;
    ssa_op--;
  }

  t1 = OP1_INFO();
  t2 = OP2_INFO();

  /* If one of the operands cannot have any type, this means the operand derives from
   * unreachable code. Propagate the empty result early, so that that the following
   * code may assume that operands have at least one type. */
  if (!(t1 & (MAY_BE_ANY|MAY_BE_UNDEF|MAY_BE_CLASS))
   || !(t2 & (MAY_BE_ANY|MAY_BE_UNDEF|MAY_BE_CLASS))
   || (ssa_op->result_use >= 0 && !(RES_USE_INFO() & (MAY_BE_ANY|MAY_BE_UNDEF|MAY_BE_CLASS)))
   || ((opline->opcode == ZEND_ASSIGN_DIM_OP
     || opline->opcode == ZEND_ASSIGN_OBJ_OP
     || opline->opcode == ZEND_ASSIGN_STATIC_PROP_OP
     || opline->opcode == ZEND_ASSIGN_DIM
     || opline->opcode == ZEND_ASSIGN_OBJ)
      && !(OP1_DATA_INFO() & (MAY_BE_ANY|MAY_BE_UNDEF|MAY_BE_CLASS)) /*&& 0*/)) {
    tmp = 0;
    if (ssa_op->result_def >= 0 && !(ssa_var_info[ssa_op->result_def].type & MAY_BE_REF)) {
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
    }
    if (ssa_op->op1_def >= 0 && !(ssa_var_info[ssa_op->op1_def].type & MAY_BE_REF)) {
      UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
    }
    if (ssa_op->op2_def >= 0 && !(ssa_var_info[ssa_op->op2_def].type & MAY_BE_REF)) {
      UPDATE_SSA_TYPE(tmp, ssa_op->op2_def);
    }
    if (opline->opcode == ZEND_ASSIGN_DIM_OP
     || opline->opcode == ZEND_ASSIGN_OBJ_OP
     || opline->opcode == ZEND_ASSIGN_STATIC_PROP_OP
     || opline->opcode == ZEND_ASSIGN_DIM
     || opline->opcode == ZEND_ASSIGN_OBJ) {
      if ((ssa_op+1)->op1_def >= 0 && !(ssa_var_info[(ssa_op+1)->op1_def].type & MAY_BE_REF)) {
        UPDATE_SSA_TYPE(tmp, (ssa_op+1)->op1_def);
      }
    }
    return SUCCESS;
  }

  switch (opline->opcode) {
    case ZEND_ADD:
    case ZEND_SUB:
    case ZEND_MUL:
    case ZEND_DIV:
    case ZEND_POW:
    case ZEND_MOD:
    case ZEND_BW_OR:
    case ZEND_BW_AND:
    case ZEND_BW_XOR:
    case ZEND_SL:
    case ZEND_SR:
    case ZEND_CONCAT:
      tmp = binary_op_result_type(ssa, opline->opcode, t1, t2, ssa_op->result_def, optimization_level);
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    case ZEND_BW_NOT:
      tmp = 0;
      if (t1 & MAY_BE_STRING) {
        tmp |= MAY_BE_STRING | MAY_BE_RC1 | MAY_BE_RCN;
      }
      if (t1 & (MAY_BE_ANY-MAY_BE_STRING)) {
        tmp |= MAY_BE_LONG;
      }
      if (!(ZEND_OPTIMIZER_IGNORE_OVERLOADING & optimization_level)) {
        if (t1 & MAY_BE_OBJECT) {
          /* Potentially overloaded operator. */
          tmp |= MAY_BE_OBJECT | MAY_BE_RC1;
        }
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    case ZEND_BEGIN_SILENCE:
      UPDATE_SSA_TYPE(MAY_BE_LONG, ssa_op->result_def);
      break;
    case ZEND_BOOL_NOT:
    case ZEND_BOOL_XOR:
    case ZEND_IS_IDENTICAL:
    case ZEND_IS_NOT_IDENTICAL:
    case ZEND_IS_EQUAL:
    case ZEND_IS_NOT_EQUAL:
    case ZEND_IS_SMALLER:
    case ZEND_IS_SMALLER_OR_EQUAL:
    case ZEND_INSTANCEOF:
    case ZEND_JMPZ_EX:
    case ZEND_JMPNZ_EX:
    case ZEND_CASE:
    case ZEND_CASE_STRICT:
    case ZEND_BOOL:
    case ZEND_ISSET_ISEMPTY_CV:
    case ZEND_ISSET_ISEMPTY_VAR:
    case ZEND_ISSET_ISEMPTY_DIM_OBJ:
    case ZEND_ISSET_ISEMPTY_PROP_OBJ:
    case ZEND_ISSET_ISEMPTY_STATIC_PROP:
    case ZEND_ASSERT_CHECK:
    case ZEND_IN_ARRAY:
    case ZEND_ARRAY_KEY_EXISTS:
      UPDATE_SSA_TYPE(MAY_BE_FALSE|MAY_BE_TRUE, ssa_op->result_def);
      break;
    case ZEND_CAST:
      if (ssa_op->op1_def >= 0) {
        tmp = t1;
        if ((t1 & (MAY_BE_ARRAY|MAY_BE_OBJECT)) &&
            (opline->extended_value == IS_ARRAY ||
             opline->extended_value == IS_OBJECT)) {
          tmp |= MAY_BE_RCN;
        } else if ((t1 & MAY_BE_STRING) &&
            opline->extended_value == IS_STRING) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      tmp = 1 << opline->extended_value;
      if (tmp & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
        if ((tmp & MAY_BE_ANY) == (t1 & MAY_BE_ANY)) {
          tmp |= (t1 & MAY_BE_RC1) | MAY_BE_RCN;
        } else if ((opline->extended_value == IS_ARRAY ||
              opline->extended_value == IS_OBJECT) &&
               (t1 & (MAY_BE_ARRAY|MAY_BE_OBJECT))) {
            tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        } else if (opline->extended_value == IS_STRING &&
               (t1 & (MAY_BE_STRING|MAY_BE_OBJECT))) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        } else {
          tmp |= MAY_BE_RC1;
          if (opline->extended_value == IS_ARRAY
           && (t1 & (MAY_BE_UNDEF|MAY_BE_NULL))) {
            tmp |= MAY_BE_RCN;
          }
        }
      }
      if (opline->extended_value == IS_ARRAY) {
        if (t1 & (MAY_BE_UNDEF|MAY_BE_NULL)) {
          tmp |= MAY_BE_ARRAY_EMPTY;
        }
        if (t1 & MAY_BE_ARRAY) {
          tmp |= t1 & (MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF);
        }
        if (t1 & MAY_BE_OBJECT) {
          tmp |= MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        } else if (t1 & (MAY_BE_ANY - MAY_BE_NULL)) {
          tmp |= ((t1 & (MAY_BE_ANY - MAY_BE_NULL)) << MAY_BE_ARRAY_SHIFT) | ((t1 & MAY_BE_NULL) ? MAY_BE_ARRAY_KEY_LONG : MAY_BE_ARRAY_PACKED);
        }
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    case ZEND_QM_ASSIGN:
    case ZEND_JMP_SET:
    case ZEND_COALESCE:
    case ZEND_COPY_TMP:
      if (ssa_op->op1_def >= 0) {
        tmp = t1;
        if (t1 & (MAY_BE_RC1|MAY_BE_REF)) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      tmp = t1 & ~MAY_BE_UNDEF;
      if (opline->opcode != ZEND_COPY_TMP || opline->op1_type != IS_VAR) {
        tmp &= ~MAY_BE_REF;
      }
      if (t1 & MAY_BE_UNDEF) {
        tmp |= MAY_BE_NULL;
      }
      if (t1 & (MAY_BE_RC1|MAY_BE_RCN)) {
        tmp |= (t1 & (MAY_BE_RC1|MAY_BE_RCN));
        if (opline->opcode == ZEND_COPY_TMP || opline->op1_type == IS_CV) {
          tmp |= MAY_BE_RCN;
        }
      }
      if (opline->opcode == ZEND_COALESCE || opline->opcode == ZEND_JMP_SET) {
        /* COALESCE and JMP_SET result can't be null */
        tmp &= ~MAY_BE_NULL;
        if (opline->opcode == ZEND_JMP_SET) {
          /* JMP_SET result can't be false either */
          tmp &= ~MAY_BE_FALSE;
        }
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->result_def);
      break;
    case ZEND_JMP_NULL:
    {
      uint32_t short_circuiting_type = opline->extended_value & ZEND_SHORT_CIRCUITING_CHAIN_MASK;
      if (short_circuiting_type == ZEND_SHORT_CIRCUITING_CHAIN_EXPR) {
        tmp = MAY_BE_NULL;
      } else if (short_circuiting_type == ZEND_SHORT_CIRCUITING_CHAIN_ISSET) {
        tmp = MAY_BE_FALSE;
      } else {
        ZEND_ASSERT(short_circuiting_type == ZEND_SHORT_CIRCUITING_CHAIN_EMPTY);
        tmp = MAY_BE_TRUE;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    }
    case ZEND_ASSIGN_OP:
    case ZEND_ASSIGN_DIM_OP:
    case ZEND_ASSIGN_OBJ_OP:
    case ZEND_ASSIGN_STATIC_PROP_OP:
    {
      const zend_property_info *prop_info = NULL;
      orig = 0;
      tmp = 0;
      if (opline->opcode == ZEND_ASSIGN_OBJ_OP) {
        prop_info = zend_fetch_prop_info(op_array, ssa, opline, ssa_op);
        orig = t1;
        t1 = zend_fetch_prop_type(script, prop_info, NULL);
        t2 = OP1_DATA_INFO();
      } else if (opline->opcode == ZEND_ASSIGN_DIM_OP) {
        if (t1 & MAY_BE_ARRAY_OF_REF) {
              tmp |= MAY_BE_REF;
        }
        orig = t1;
        t1 = zend_array_element_type(t1, opline->op1_type, 1, 0);
        t2 = OP1_DATA_INFO();
      } else if (opline->opcode == ZEND_ASSIGN_STATIC_PROP_OP) {
        prop_info = zend_fetch_static_prop_info(script, op_array, ssa, opline);
        t1 = zend_fetch_prop_type(script, prop_info, NULL);
        t2 = OP1_DATA_INFO();
      } else {
        if (t1 & MAY_BE_REF) {
              tmp |= MAY_BE_REF;
        }
      }

      tmp |= binary_op_result_type(
        ssa, opline->extended_value, t1, t2,
        opline->opcode == ZEND_ASSIGN_OP ? ssa_op->op1_def : -1, optimization_level);
      if (tmp & (MAY_BE_STRING|MAY_BE_ARRAY)) {
        tmp |= MAY_BE_RC1 | MAY_BE_RCN;
      }
      if (tmp & (MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
        tmp |= MAY_BE_RC1 | MAY_BE_RCN;
      }

      if (opline->opcode == ZEND_ASSIGN_DIM_OP) {
        if (opline->op1_type == IS_CV) {
          orig = assign_dim_result_type(orig, OP2_INFO(), tmp, opline->op2_type);
          UPDATE_SSA_TYPE(orig, ssa_op->op1_def);
          COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
        }
      } else if (opline->opcode == ZEND_ASSIGN_OBJ_OP) {
        if (opline->op1_type == IS_CV) {
          orig = (orig & (MAY_BE_REF|MAY_BE_OBJECT))|MAY_BE_RC1|MAY_BE_RCN;
          UPDATE_SSA_TYPE(orig, ssa_op->op1_def);
          COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
        }
      } else if (opline->opcode == ZEND_ASSIGN_STATIC_PROP_OP) {
        /* Nothing to do */
      } else {
        if (opline->opcode == ZEND_ASSIGN_OP && ssa_op->result_def >= 0 && (tmp & MAY_BE_RC1)) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        ce = NULL;
        if (opline->opcode == ZEND_ASSIGN_DIM_OP) {
          if (opline->op2_type == IS_UNUSED) {
            /* When appending to an array and the LONG_MAX key is already used
             * null will be returned. */
            tmp |= MAY_BE_NULL;
          }
          if (t2 & (MAY_BE_ARRAY | MAY_BE_OBJECT)) {
            /* Arrays and objects cannot be used as keys. */
            tmp |= MAY_BE_NULL;
          }
          if (t1 & (MAY_BE_ANY - (MAY_BE_NULL | MAY_BE_FALSE | MAY_BE_STRING | MAY_BE_ARRAY))) {
            /* null and false are implicitly converted to array, anything else
             * results in a null return value. */
            tmp |= MAY_BE_NULL;
          }
          if (tmp & MAY_BE_REF) {
            /* Typed reference may cause auto conversion */
            tmp |= MAY_BE_ANY;
          }
        } else if (opline->opcode == ZEND_ASSIGN_OBJ_OP) {
          /* The return value must also satisfy the property type */
          if (prop_info) {
            t1 = zend_fetch_prop_type(script, prop_info, &ce);
            if ((t1 & (MAY_BE_LONG|MAY_BE_DOUBLE)) == MAY_BE_LONG
             && (tmp & (MAY_BE_LONG|MAY_BE_DOUBLE)) == MAY_BE_DOUBLE) {
              /* DOUBLE may be auto-converted to LONG */
              tmp |= MAY_BE_LONG;
              tmp &= ~MAY_BE_DOUBLE;
            } else if ((t1 & (MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_STRING)) == MAY_BE_STRING
             && (tmp & (MAY_BE_LONG|MAY_BE_DOUBLE))) {
              /* LONG/DOUBLE may be auto-converted to STRING */
              tmp |= MAY_BE_STRING;
              tmp &= ~(MAY_BE_LONG|MAY_BE_DOUBLE);
            }
            tmp &= t1;
          } else {
            tmp |= MAY_BE_LONG | MAY_BE_STRING;
          }
        } else if (opline->opcode == ZEND_ASSIGN_STATIC_PROP_OP) {
          /* The return value must also satisfy the property type */
          if (prop_info) {
            t1 = zend_fetch_prop_type(script, prop_info, &ce);
            if ((t1 & (MAY_BE_LONG|MAY_BE_DOUBLE)) == MAY_BE_LONG
             && (tmp & (MAY_BE_LONG|MAY_BE_DOUBLE)) == MAY_BE_DOUBLE) {
              /* DOUBLE may be auto-converted to LONG */
              tmp |= MAY_BE_LONG;
              tmp &= ~MAY_BE_DOUBLE;
            } else if ((t1 & (MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_STRING)) == MAY_BE_STRING
             && (tmp & (MAY_BE_LONG|MAY_BE_DOUBLE))) {
              /* LONG/DOUBLE may be auto-converted to STRING */
              tmp |= MAY_BE_STRING;
              tmp &= ~(MAY_BE_LONG|MAY_BE_DOUBLE);
            }
            tmp &= t1;
          } else {
            tmp |= MAY_BE_LONG | MAY_BE_STRING;
          }
        } else {
          if (tmp & MAY_BE_REF) {
            /* Typed reference may cause auto conversion */
            tmp |= MAY_BE_ANY;
          }
        }
        tmp &= ~MAY_BE_REF;
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
        if (ce) {
          UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->result_def);
        }
      }
      break;
    }
    case ZEND_PRE_INC:
    case ZEND_PRE_DEC:
      tmp = 0;
      if (t1 & (MAY_BE_RC1|MAY_BE_RCN)) {
        tmp |= MAY_BE_RC1;
        if (ssa_op->result_def >= 0) {
          tmp |= MAY_BE_RCN;
        }
      }
      if ((t1 & (MAY_BE_ANY|MAY_BE_UNDEF)) == MAY_BE_LONG) {
        if (!ssa_var_info[ssa_op->op1_use].has_range ||
            (opline->opcode == ZEND_PRE_DEC &&
             (ssa_var_info[ssa_op->op1_use].range.underflow ||
              ssa_var_info[ssa_op->op1_use].range.min == ZEND_LONG_MIN)) ||
             (opline->opcode == ZEND_PRE_INC &&
              (ssa_var_info[ssa_op->op1_use].range.overflow ||
               ssa_var_info[ssa_op->op1_use].range.max == ZEND_LONG_MAX))) {
          /* may overflow */
          tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        } else {
          tmp |= MAY_BE_LONG;
        }
      } else {
        if (t1 & (MAY_BE_UNDEF | MAY_BE_NULL)) {
          if (opline->opcode == ZEND_PRE_INC) {
            tmp |= MAY_BE_LONG;
          } else {
            tmp |= MAY_BE_NULL;
          }
        }
        if (t1 & MAY_BE_LONG) {
          tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        }
        if (t1 & MAY_BE_DOUBLE) {
          tmp |= MAY_BE_DOUBLE;
        }
        if (t1 & MAY_BE_STRING) {
          tmp |= MAY_BE_STRING | MAY_BE_LONG | MAY_BE_DOUBLE;
        }
        tmp |= t1 & (MAY_BE_FALSE | MAY_BE_TRUE | MAY_BE_OBJECT);
      }
      if (ssa_op->result_def >= 0) {
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      if (ssa_op->op1_def >= 0) {
        if (t1 & MAY_BE_REF) {
          tmp |= MAY_BE_REF;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_POST_INC:
    case ZEND_POST_DEC:
      if (ssa_op->result_def >= 0) {
        tmp = 0;
        if (t1 & (MAY_BE_RC1|MAY_BE_RCN)) {
          tmp |= MAY_BE_RC1|MAY_BE_RCN;
        }
        tmp |= t1 & ~(MAY_BE_UNDEF|MAY_BE_REF|MAY_BE_RCN);
        if (t1 & MAY_BE_UNDEF) {
          tmp |= MAY_BE_NULL;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      tmp = 0;
      if (t1 & MAY_BE_REF) {
        tmp |= MAY_BE_REF;
      }
      if (t1 & (MAY_BE_RC1|MAY_BE_RCN)) {
        tmp |= MAY_BE_RC1;
      }
      if ((t1 & (MAY_BE_ANY|MAY_BE_UNDEF)) == MAY_BE_LONG) {
        if (!ssa_var_info[ssa_op->op1_use].has_range ||
             (opline->opcode == ZEND_POST_DEC &&
              (ssa_var_info[ssa_op->op1_use].range.underflow ||
               ssa_var_info[ssa_op->op1_use].range.min == ZEND_LONG_MIN)) ||
              (opline->opcode == ZEND_POST_INC &&
               (ssa_var_info[ssa_op->op1_use].range.overflow ||
                ssa_var_info[ssa_op->op1_use].range.max == ZEND_LONG_MAX))) {
          /* may overflow */
          tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        } else {
          tmp |= MAY_BE_LONG;
        }
      } else {
        if (t1 & (MAY_BE_UNDEF | MAY_BE_NULL)) {
          if (opline->opcode == ZEND_POST_INC) {
            tmp |= MAY_BE_LONG;
          } else {
            tmp |= MAY_BE_NULL;
          }
        }
        if (t1 & MAY_BE_LONG) {
          tmp |= MAY_BE_LONG | MAY_BE_DOUBLE;
        }
        if (t1 & MAY_BE_DOUBLE) {
          tmp |= MAY_BE_DOUBLE;
        }
        if (t1 & MAY_BE_STRING) {
          tmp |= MAY_BE_STRING | MAY_BE_LONG | MAY_BE_DOUBLE;
        }
        tmp |= t1 & (MAY_BE_FALSE | MAY_BE_TRUE | MAY_BE_RESOURCE | MAY_BE_ARRAY | MAY_BE_OBJECT | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_KEY_ANY);
      }
      if (ssa_op->op1_def >= 0) {
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_ASSIGN_DIM:
      if (opline->op1_type == IS_CV) {
        tmp = assign_dim_result_type(t1, t2, OP1_DATA_INFO(), opline->op2_type);
        tmp |= ssa->var_info[ssa_op->op1_def].type & (MAY_BE_ARRAY_PACKED|MAY_BE_ARRAY_NUMERIC_HASH|MAY_BE_ARRAY_STRING_HASH);
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        tmp = 0;
        if (t1 & MAY_BE_STRING) {
          tmp |= MAY_BE_STRING | MAY_BE_NULL;
        }
        if (t1 & MAY_BE_OBJECT) {
          tmp |= (MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF);
        }
        if (t1 & (MAY_BE_ARRAY|MAY_BE_FALSE|MAY_BE_NULL|MAY_BE_UNDEF)) {
          tmp |= (OP1_DATA_INFO() & (MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF));

          if (OP1_DATA_INFO() & MAY_BE_UNDEF) {
            tmp |= MAY_BE_NULL;
          }
          if (t1 & MAY_BE_ARRAY_OF_REF) {
            /* A scalar type conversion may occur when assigning to a typed reference. */
            tmp |= MAY_BE_NULL|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_STRING;
          }
        }
        if (t1 & (MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_RESOURCE)) {
          tmp |= MAY_BE_NULL;
        }
        tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      if ((ssa_op+1)->op1_def >= 0) {
        opline++;
        ssa_op++;
        tmp = OP1_INFO();
        if (tmp & (MAY_BE_ANY | MAY_BE_REF)) {
          if (tmp & MAY_BE_RC1) {
            tmp |= MAY_BE_RCN;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_ASSIGN_OBJ:
      if (opline->op1_type == IS_CV) {
        const zend_class_entry *ce = ssa_var_info[ssa_op->op1_use].ce;
        bool add_rc = (t1 & (MAY_BE_OBJECT|MAY_BE_REF)) && (!ce
          || ce->__set
          /* Non-default write_property may be set within create_object. */
          || ce->create_object
          || ce->default_object_handlers->write_property != zend_std_write_property
          || ssa_var_info[ssa_op->op1_use].is_instanceof);
        tmp = (t1 & (MAY_BE_REF|MAY_BE_OBJECT|MAY_BE_RC1|MAY_BE_RCN))|(add_rc ? (MAY_BE_RC1|MAY_BE_RCN) : 0);
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        // TODO: If there is no __set we might do better
        tmp = zend_fetch_prop_type(script,
          zend_fetch_prop_info(op_array, ssa, opline, ssa_op), &ce);
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
        if (ce) {
          UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->result_def);
        }
      }
      if ((ssa_op+1)->op1_def >= 0) {
        opline++;
        ssa_op++;
        tmp = OP1_INFO();
        if (tmp & MAY_BE_RC1) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_ASSIGN_STATIC_PROP:
      if (ssa_op->result_def >= 0) {
        tmp = MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_RC1 | MAY_BE_RCN;
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      if ((ssa_op+1)->op1_def >= 0) {
        opline++;
        ssa_op++;
        tmp = OP1_INFO();
        if (tmp & MAY_BE_RC1) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_PRE_INC_OBJ:
    case ZEND_PRE_DEC_OBJ:
    case ZEND_POST_INC_OBJ:
    case ZEND_POST_DEC_OBJ:
      if (opline->op1_type == IS_CV) {
        tmp = (t1 & (MAY_BE_REF|MAY_BE_OBJECT))|MAY_BE_RC1|MAY_BE_RCN;
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        // TODO: ???
        tmp = MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
    case ZEND_ASSIGN:
      if (ssa_op->op2_def >= 0) {
        tmp = t2;
        if (tmp & MAY_BE_RC1) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op2_def);
      }
      tmp = t2 & ~(MAY_BE_UNDEF|MAY_BE_REF|MAY_BE_RC1|MAY_BE_RCN);
      if (t2 & MAY_BE_UNDEF) {
        tmp |= MAY_BE_NULL;
      }
      if (t1 & MAY_BE_REF) {
        tmp |= MAY_BE_REF;
      }
      if (t2 & MAY_BE_REF) {
        tmp |= MAY_BE_RC1 | MAY_BE_RCN;
      } else if (opline->op2_type & (IS_TMP_VAR|IS_VAR)) {
        tmp |= t2 & (MAY_BE_RC1|MAY_BE_RCN);
      } else if (t2 & (MAY_BE_RC1|MAY_BE_RCN)) {
        tmp |= MAY_BE_RCN;
      }
      if (RETURN_VALUE_USED(opline) && (tmp & MAY_BE_RC1)) {
        tmp |= MAY_BE_RCN;
      }
      if (ssa_op->op1_def >= 0) {
        if (ssa_var_info[ssa_op->op1_def].use_as_double) {
          tmp &= ~MAY_BE_LONG;
          tmp |= MAY_BE_DOUBLE;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op2_use, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        if (tmp & MAY_BE_REF) {
          /* A scalar type conversion may occur when assigning to a typed reference. */
          tmp &= ~MAY_BE_REF;
          tmp |= MAY_BE_NULL|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_STRING|MAY_BE_RC1|MAY_BE_RCN;
        }
        if ((tmp & (MAY_BE_RC1|MAY_BE_RCN)) == MAY_BE_RCN) {
          /* refcount may be indirectly decremented. Make an exception if the result is used in the next instruction */
          if (!ssa_opcodes) {
            if (ssa->vars[ssa_op->result_def].use_chain < 0
             || opline + 1 != op_array->opcodes + ssa->vars[ssa_op->result_def].use_chain) {
              tmp |= MAY_BE_RC1;
              }
          } else {
            if (ssa->vars[ssa_op->result_def].use_chain < 0
             || opline + 1 != ssa_opcodes[ssa->vars[ssa_op->result_def].use_chain]) {
              tmp |= MAY_BE_RC1;
              }
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op2_use, ssa_op->result_def);
      }
      break;
    case ZEND_ASSIGN_REF:
// TODO: ???
      if (opline->op2_type == IS_CV) {
        tmp = (MAY_BE_REF | t2) & ~(MAY_BE_UNDEF|MAY_BE_RC1|MAY_BE_RCN);
        if (t2 & MAY_BE_UNDEF) {
          tmp |= MAY_BE_NULL;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op2_def);
      }
      if (opline->op2_type == IS_VAR && opline->extended_value == ZEND_RETURNS_FUNCTION) {
        tmp = (MAY_BE_REF | MAY_BE_RCN | MAY_BE_RC1 | t2) & ~MAY_BE_UNDEF;
      } else {
        tmp = (MAY_BE_REF | t2) & ~(MAY_BE_UNDEF|MAY_BE_RC1|MAY_BE_RCN);
      }
      if (t2 & MAY_BE_UNDEF) {
        tmp |= MAY_BE_NULL;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      if (ssa_op->result_def >= 0) {
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
    case ZEND_ASSIGN_OBJ_REF:
      if (opline->op1_type == IS_CV && ssa_op->op1_def >= 0) {
        tmp = t1;
        if (tmp & MAY_BE_OBJECT) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }

      t2 = OP1_DATA_INFO();
      if ((opline+1)->op1_type == IS_VAR && (opline->extended_value & ZEND_RETURNS_FUNCTION)) {
        tmp = (MAY_BE_REF | MAY_BE_RCN | MAY_BE_RC1 | t2) & ~MAY_BE_UNDEF;
      } else {
        tmp = (MAY_BE_REF | t2) & ~(MAY_BE_UNDEF|MAY_BE_RC1|MAY_BE_RCN);
      }
      if (t2 & MAY_BE_UNDEF) {
        tmp |= MAY_BE_NULL;
      }
      if (ssa_op->result_def >= 0) {
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      if ((opline+1)->op1_type == IS_CV) {
        opline++;
        ssa_op++;
        tmp = (MAY_BE_REF | t2) & ~(MAY_BE_UNDEF|MAY_BE_RC1|MAY_BE_RCN);
        if (t2 & MAY_BE_UNDEF) {
          tmp |= MAY_BE_NULL;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_ASSIGN_STATIC_PROP_REF:
      if (ssa_op->result_def >= 0) {
        UPDATE_SSA_TYPE(MAY_BE_REF, ssa_op->result_def);
      }
      if ((opline+1)->op1_type == IS_CV) {
        opline++;
        ssa_op++;
        UPDATE_SSA_TYPE(MAY_BE_REF, ssa_op->op1_def);
      }
      break;
    case ZEND_BIND_GLOBAL:
      tmp = MAY_BE_REF | MAY_BE_ANY
        | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
      UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      break;
    case ZEND_BIND_STATIC:
      tmp = MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF
        | ((opline->extended_value & ZEND_BIND_REF) ? MAY_BE_REF : (MAY_BE_RC1 | MAY_BE_RCN));
      if (opline->extended_value & ZEND_BIND_IMPLICIT) {
        tmp |= MAY_BE_UNDEF;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      break;
    case ZEND_BIND_INIT_STATIC_OR_JMP:
      tmp = MAY_BE_UNDEF | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_REF;
      UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      break;
    case ZEND_SEND_VAR:
      if (ssa_op->op1_def >= 0) {
        tmp = t1;
        if (t1 & (MAY_BE_RC1|MAY_BE_REF)) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      break;
    case ZEND_BIND_LEXICAL:
      if (ssa_op->op2_def >= 0) {
        if (opline->extended_value & ZEND_BIND_REF) {
          tmp = t2 | MAY_BE_REF;
        } else {
          tmp = t2 & ~(MAY_BE_RC1|MAY_BE_RCN);
          if (t2 & (MAY_BE_RC1|MAY_BE_RCN)) {
            tmp |= MAY_BE_RCN;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op2_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op2_use, ssa_op->op2_def);
      }
      break;
    case ZEND_YIELD:
      if (ssa_op->op1_def >= 0) {
        if (op_array->fn_flags & ZEND_ACC_RETURN_REFERENCE) {
          tmp = t1 | MAY_BE_REF;
        } else {
          tmp = t1 & ~(MAY_BE_RC1|MAY_BE_RCN);
          if (t1 & (MAY_BE_RC1|MAY_BE_RCN)) {
            tmp |= MAY_BE_RCN;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        tmp = MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF
          | MAY_BE_RC1 | MAY_BE_RCN;
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
    case ZEND_SEND_VAR_EX:
    case ZEND_SEND_FUNC_ARG:
      if (ssa_op->op1_def >= 0) {
        tmp = (t1 & MAY_BE_UNDEF)|MAY_BE_REF|MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ANY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF;
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_SEND_REF:
      if (ssa_op->op1_def >= 0) {
        tmp = MAY_BE_REF|MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ANY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF;
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_SEND_UNPACK:
      if (ssa_op->op1_def >= 0) {
        tmp = t1;
        if (t1 & MAY_BE_ARRAY) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
          if (t1 & MAY_BE_ARRAY_OF_ANY) {
            /* SEND_UNPACK may acquire references into the array */
            tmp |= MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
          }
        }
        if (t1 & MAY_BE_OBJECT) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_FAST_CONCAT:
    case ZEND_ROPE_INIT:
    case ZEND_ROPE_ADD:
    case ZEND_ROPE_END:
      UPDATE_SSA_TYPE(MAY_BE_STRING|MAY_BE_RC1|MAY_BE_RCN, ssa_op->result_def);
      break;
    case ZEND_RECV:
    case ZEND_RECV_INIT:
    case ZEND_RECV_VARIADIC:
    {
      /* Typehinting */
      zend_arg_info *arg_info = &op_array->arg_info[opline->op1.num-1];

      ce = NULL;
      tmp = zend_fetch_arg_info_type(script, arg_info, &ce);
      if (ZEND_ARG_SEND_MODE(arg_info)) {
        tmp |= MAY_BE_REF;
        ce = NULL;
      }

      if (opline->opcode == ZEND_RECV_VARIADIC) {
        uint32_t elem_type = tmp & MAY_BE_REF
          ? MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF
          : (tmp & MAY_BE_ANY) << MAY_BE_ARRAY_SHIFT;
        tmp = MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_ANY|elem_type;
        ce = NULL;
      }

      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      if (ce) {
        UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->result_def);
      } else {
        UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
      }
      break;
    }
    case ZEND_DECLARE_ANON_CLASS:
      UPDATE_SSA_TYPE(MAY_BE_CLASS, ssa_op->result_def);
      if (script && (ce = zend_hash_find_ptr(&script->class_table, Z_STR_P(CRT_CONSTANT(opline->op1)))) != NULL) {
        UPDATE_SSA_OBJ_TYPE(ce, 0, ssa_op->result_def);
      }
      break;
    case ZEND_FETCH_CLASS:
      UPDATE_SSA_TYPE(MAY_BE_CLASS, ssa_op->result_def);
      if (opline->op2_type == IS_UNUSED) {
        switch (opline->op1.num & ZEND_FETCH_CLASS_MASK) {
          case ZEND_FETCH_CLASS_SELF:
            if (op_array->scope) {
              UPDATE_SSA_OBJ_TYPE(op_array->scope, 0, ssa_op->result_def);
            } else {
              UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
            }
            break;
          case ZEND_FETCH_CLASS_PARENT:
            if (op_array->scope && op_array->scope->parent && (op_array->scope->ce_flags & ZEND_ACC_LINKED)) {
              UPDATE_SSA_OBJ_TYPE(op_array->scope->parent, 0, ssa_op->result_def);
            } else {
              UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
            }
            break;
          case ZEND_FETCH_CLASS_STATIC:
            if (op_array->scope && (op_array->scope->ce_flags & ZEND_ACC_FINAL)) {
              UPDATE_SSA_OBJ_TYPE(op_array->scope, 0, ssa_op->result_def);
            } else {
              UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
            }
            break;
          default:
            UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
            break;
        }
      } else if (opline->op2_type == IS_CONST) {
        zval *zv = CRT_CONSTANT(opline->op2);
        if (Z_TYPE_P(zv) == IS_STRING) {
          ce = zend_optimizer_get_class_entry(script, op_array, Z_STR_P(zv+1));
          UPDATE_SSA_OBJ_TYPE(ce, 0, ssa_op->result_def);
        } else {
          UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
        }
      } else {
        COPY_SSA_OBJ_TYPE(ssa_op->op2_use, ssa_op->result_def);
      }
      break;
    case ZEND_NEW:
      tmp = MAY_BE_RC1|MAY_BE_RCN|MAY_BE_OBJECT;
      ce = zend_optimizer_get_class_entry_from_op1(script, op_array, opline);
      if (ce) {
        UPDATE_SSA_OBJ_TYPE(ce, 0, ssa_op->result_def);
      } else if ((t1 & MAY_BE_CLASS) && ssa_op->op1_use >= 0 && ssa_var_info[ssa_op->op1_use].ce) {
        UPDATE_SSA_OBJ_TYPE(ssa_var_info[ssa_op->op1_use].ce, ssa_var_info[ssa_op->op1_use].is_instanceof, ssa_op->result_def);
        if (!ssa_var_info[ssa_op->result_def].is_instanceof) {
          ce = ssa_var_info[ssa_op->op1_use].ce;
        }
      } else {
        UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
      }
      /* New objects without constructors cannot escape. */
      if (ce
       && !ce->constructor
       && !ce->create_object
       && ce->default_object_handlers->get_constructor == zend_std_get_constructor) {
        tmp &= ~MAY_BE_RCN;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    case ZEND_CLONE:
      UPDATE_SSA_TYPE(MAY_BE_RC1|MAY_BE_RCN|MAY_BE_OBJECT, ssa_op->result_def);
      COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->result_def);
      break;
    case ZEND_INIT_ARRAY:
    case ZEND_ADD_ARRAY_ELEMENT:
      if (ssa_op->op1_def >= 0) {
        if (opline->extended_value & ZEND_ARRAY_ELEMENT_REF) {
          tmp = (MAY_BE_REF | t1) & ~(MAY_BE_UNDEF|MAY_BE_RC1|MAY_BE_RCN);
          if (t1 & MAY_BE_UNDEF) {
            tmp |= MAY_BE_NULL;
          }
        } else if ((t1 & (MAY_BE_REF|MAY_BE_RC1|MAY_BE_RCN)) == MAY_BE_REF) {
          tmp = (MAY_BE_REF | t1) & ~(MAY_BE_UNDEF|MAY_BE_RC1|MAY_BE_RCN);
          if (t1 & MAY_BE_UNDEF) {
            tmp |= MAY_BE_NULL;
          }
        } else if (t1 & MAY_BE_REF) {
          tmp = (MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_REF | t1);
        } else {
          tmp = t1;
          if (t1 & MAY_BE_RC1) {
            tmp |= MAY_BE_RCN;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      if (ssa_op->result_def >= 0) {
        uint32_t arr_type;
        if (opline->opcode == ZEND_INIT_ARRAY) {
          arr_type = 0;
        } else {
          arr_type = RES_USE_INFO();
        }
        tmp = MAY_BE_RC1|MAY_BE_ARRAY|arr_type;
        if (opline->opcode == ZEND_INIT_ARRAY && opline->op1_type == IS_UNUSED) {
          tmp |= MAY_BE_ARRAY_EMPTY;
        }
        if (opline->op1_type != IS_UNUSED
         && (opline->op2_type == IS_UNUSED
          || (t2 & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_RESOURCE|MAY_BE_STRING)))) {
          tmp |= assign_dim_array_result_type(arr_type, t2, t1, opline->op2_type);
          if (opline->extended_value & ZEND_ARRAY_ELEMENT_REF) {
            tmp |= MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
    case ZEND_ADD_ARRAY_UNPACK:
      tmp = ssa_var_info[ssa_op->result_use].type;
      ZEND_ASSERT(tmp & MAY_BE_ARRAY);
      tmp |= t1 & (MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF);
      if (t1 & MAY_BE_OBJECT) {
        tmp |= MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    case ZEND_UNSET_CV:
      tmp = MAY_BE_UNDEF;
      if (!op_array->function_name) {
        /* In global scope, we know nothing */
        tmp |= MAY_BE_REF;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      break;
    case ZEND_UNSET_DIM:
    case ZEND_UNSET_OBJ:
      if (ssa_op->op1_def >= 0) {
        UPDATE_SSA_TYPE(t1, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      break;
    case ZEND_FE_RESET_R:
    case ZEND_FE_RESET_RW:
      if (ssa_op->op1_def >= 0) {
        tmp = t1;
        if (opline->opcode == ZEND_FE_RESET_RW) {
          tmp |= MAY_BE_REF;
        } else if (t1 & MAY_BE_RC1) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      if (opline->opcode == ZEND_FE_RESET_RW) {
//???
        tmp = MAY_BE_REF | (t1 & (MAY_BE_ARRAY | MAY_BE_OBJECT));
      } else {
        tmp = MAY_BE_RC1 | MAY_BE_RCN | (t1 & (MAY_BE_ARRAY | MAY_BE_OBJECT | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF));
      }
      /* The result is set to UNDEF for invalid foreach inputs. */
      if ((t1 & (MAY_BE_ANY | MAY_BE_UNDEF)) & ~(MAY_BE_ARRAY | MAY_BE_OBJECT)) {
        tmp |= MAY_BE_UNDEF;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->result_def);
      break;
    case ZEND_FE_FETCH_R:
    case ZEND_FE_FETCH_RW:
      tmp = 0;
      if (opline->op2_type == IS_CV) {
        tmp = t2 & MAY_BE_REF;
      }
      if (t1 & MAY_BE_OBJECT) {
        if (opline->opcode == ZEND_FE_FETCH_RW) {
          tmp |= MAY_BE_REF | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        } else {
          tmp |= MAY_BE_RCN | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
          if (opline->op2_type != IS_CV) {
            tmp |= MAY_BE_REF;
          }
        }
      }
      if (t1 & MAY_BE_ARRAY) {
        if (opline->opcode == ZEND_FE_FETCH_RW) {
          tmp |= MAY_BE_REF | MAY_BE_RCN | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        } else {
          tmp |= ((t1 & MAY_BE_ARRAY_OF_ANY) >> MAY_BE_ARRAY_SHIFT);
          if (tmp & MAY_BE_ARRAY) {
            tmp |= MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
          }
          if (t1 & MAY_BE_ARRAY_OF_REF) {
            tmp |= MAY_BE_RC1 | MAY_BE_RCN;
            if (opline->op2_type != IS_CV) {
              tmp |= MAY_BE_REF;
            }
          } else if (tmp & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
            tmp |= MAY_BE_RC1 | MAY_BE_RCN;
          }
        }
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->op2_def);
      if (ssa_op->result_def >= 0) {
        tmp = (ssa_op->result_use >= 0) ? RES_USE_INFO() : 0;
        if (t1 & MAY_BE_OBJECT) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        }
        if (t1 & MAY_BE_ARRAY) {
          if (t1 & MAY_BE_ARRAY_KEY_LONG) {
            tmp |= MAY_BE_LONG;
          }
          if (t1 & MAY_BE_ARRAY_KEY_STRING) {
            tmp |= MAY_BE_STRING | MAY_BE_RCN;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
    case ZEND_FETCH_DIM_R:
    case ZEND_FETCH_DIM_IS:
    case ZEND_FETCH_DIM_RW:
    case ZEND_FETCH_DIM_W:
    case ZEND_FETCH_DIM_UNSET:
    case ZEND_FETCH_DIM_FUNC_ARG:
    case ZEND_FETCH_LIST_R:
    case ZEND_FETCH_LIST_W:
      if (ssa_op->op1_def >= 0) {
        uint32_t key_type = 0;
        tmp = t1 & ~(MAY_BE_RC1|MAY_BE_RCN);
        if (opline->opcode == ZEND_FETCH_DIM_W ||
            opline->opcode == ZEND_FETCH_DIM_RW ||
            opline->opcode == ZEND_FETCH_DIM_FUNC_ARG ||
            opline->opcode == ZEND_FETCH_LIST_W) {
          if (t1 & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
            if (opline->opcode != ZEND_FETCH_DIM_FUNC_ARG) {
              tmp &= ~(MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE);
            }
            tmp |= MAY_BE_ARRAY | MAY_BE_RC1;
          }
          if (t1 & (MAY_BE_STRING|MAY_BE_ARRAY)) {
            tmp |= MAY_BE_RC1;
            if (opline->opcode == ZEND_FETCH_DIM_FUNC_ARG) {
              tmp |= t1 & MAY_BE_RCN;
            }
          }
          if (t1 & (MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
            tmp |= t1 & (MAY_BE_RC1|MAY_BE_RCN);
          }
          if (opline->op2_type == IS_UNUSED) {
            if (t1 & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
              key_type |= MAY_BE_ARRAY_PACKED;
            }
            if (t1 & MAY_BE_ARRAY) {
              key_type |= MAY_BE_HASH_ONLY(t1) ?
                MAY_BE_ARRAY_NUMERIC_HASH : MAY_BE_ARRAY_KEY_LONG;
            }
          } else {
            if (t2 & (MAY_BE_LONG|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_RESOURCE|MAY_BE_DOUBLE)) {
              if (t1 & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
                key_type |= MAY_BE_ARRAY_PACKED;
              }
              if (t1 & MAY_BE_ARRAY) {
                key_type |= MAY_BE_HASH_ONLY(t1) ?
                  MAY_BE_ARRAY_NUMERIC_HASH : MAY_BE_ARRAY_KEY_LONG;
                }
            }
            if (t2 & MAY_BE_STRING) {
              key_type |= MAY_BE_ARRAY_KEY_STRING;
              if (opline->op2_type != IS_CONST) {
                // FIXME: numeric string
                if (t1 & (MAY_BE_UNDEF|MAY_BE_NULL|MAY_BE_FALSE)) {
                  key_type |= MAY_BE_ARRAY_PACKED;
                }
                if (t1 & MAY_BE_ARRAY) {
                  key_type |= MAY_BE_HASH_ONLY(t1) ?
                    MAY_BE_ARRAY_NUMERIC_HASH : MAY_BE_ARRAY_KEY_LONG;
                  }
              }
            }
            if (t2 & (MAY_BE_UNDEF | MAY_BE_NULL)) {
              key_type |= MAY_BE_ARRAY_KEY_STRING;
            }
          }
        } else if (opline->opcode == ZEND_FETCH_DIM_UNSET) {
          if (t1 & MAY_BE_ARRAY) {
            tmp |= MAY_BE_RC1;
          }
          if (t1 & (MAY_BE_OBJECT|MAY_BE_RESOURCE)) {
            tmp |= t1 & (MAY_BE_RC1|MAY_BE_RCN);
          }
        }
        if ((key_type & (MAY_BE_ARRAY_KEY_LONG|MAY_BE_ARRAY_KEY_STRING))
            && (opline->opcode == ZEND_FETCH_DIM_RW
            || opline->opcode == ZEND_FETCH_DIM_W
            || opline->opcode == ZEND_FETCH_DIM_FUNC_ARG
            || opline->opcode == ZEND_FETCH_LIST_W)) {
          j = ssa_vars[ssa_op->result_def].use_chain;
          if (j < 0) {
            /* no uses */
            tmp |= key_type | MAY_BE_ARRAY | MAY_BE_ARRAY_OF_NULL;
          }
          while (j >= 0) {
            uint8_t opcode;

            if (!ssa_opcodes) {
              if (j != (opline - op_array->opcodes) + 1) {
                /* Use must be in next opline */
                tmp |= key_type | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
                break;
              }
              opcode = op_array->opcodes[j].opcode;
            } else {
              if (ssa_opcodes[j] != opline + 1) {
                /* Use must be in next opline */
                tmp |= key_type | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
                break;
              }
              opcode = ssa_opcodes[j]->opcode;
            }
            switch (opcode) {
              case ZEND_FETCH_DIM_W:
              case ZEND_FETCH_DIM_RW:
              case ZEND_FETCH_DIM_FUNC_ARG:
              case ZEND_FETCH_LIST_W:
              case ZEND_ASSIGN_DIM:
              case ZEND_ASSIGN_DIM_OP:
                tmp |= key_type | MAY_BE_ARRAY | MAY_BE_ARRAY_OF_ARRAY;
                break;
              case ZEND_SEND_VAR_EX:
              case ZEND_SEND_FUNC_ARG:
              case ZEND_SEND_VAR_NO_REF:
              case ZEND_SEND_VAR_NO_REF_EX:
              case ZEND_SEND_REF:
              case ZEND_ASSIGN_REF:
              case ZEND_YIELD:
              case ZEND_INIT_ARRAY:
              case ZEND_ADD_ARRAY_ELEMENT:
              case ZEND_RETURN_BY_REF:
              case ZEND_VERIFY_RETURN_TYPE:
              case ZEND_MAKE_REF:
              case ZEND_FE_RESET_RW:
                tmp |= key_type | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
                break;
              case ZEND_PRE_INC:
              case ZEND_PRE_DEC:
              case ZEND_POST_INC:
              case ZEND_POST_DEC:
                if (tmp & MAY_BE_ARRAY_OF_LONG) {
                  /* may overflow */
                  tmp |= key_type | MAY_BE_ARRAY_OF_DOUBLE;
                } else if (!(tmp & (MAY_BE_ARRAY_OF_LONG|MAY_BE_ARRAY_OF_DOUBLE))) {
                  tmp |= key_type | MAY_BE_ARRAY_OF_LONG | MAY_BE_ARRAY_OF_DOUBLE;
                }
                break;
              case ZEND_FETCH_OBJ_W:
              case ZEND_FETCH_OBJ_RW:
              case ZEND_FETCH_OBJ_FUNC_ARG:
              case ZEND_ASSIGN_OBJ:
              case ZEND_ASSIGN_OBJ_OP:
              case ZEND_ASSIGN_OBJ_REF:
              case ZEND_PRE_INC_OBJ:
              case ZEND_PRE_DEC_OBJ:
              case ZEND_POST_INC_OBJ:
              case ZEND_POST_DEC_OBJ:
                /* These will result in an error exception, unless the element
                 * is already an object. */
                break;
              case ZEND_SEND_VAR:
              case ZEND_FETCH_DIM_R:
                /* This can occur if a DIM_FETCH_FUNC_ARG with UNUSED op2 is left
                 * behind, because it can't be converted to DIM_FETCH_R. */
                break;
              case ZEND_FREE:
                /* This may happen if the using opcode is DCEd.  */
                break;
              default: ZEND_UNREACHABLE();
            }
            j = zend_ssa_next_use(ssa->ops, ssa_op->result_def, j);
            if (j >= 0) {
              tmp |= key_type | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
              break;
            }
          }
          if (opline->opcode != ZEND_FETCH_DIM_FUNC_ARG) {
            tmp &= ~MAY_BE_ARRAY_EMPTY;
          }
        }
        if (!(tmp & MAY_BE_ARRAY)
         || (tmp & MAY_BE_ARRAY_KEY_ANY)
         || opline->opcode == ZEND_FETCH_DIM_FUNC_ARG
         || opline->opcode == ZEND_FETCH_DIM_R
         || opline->opcode == ZEND_FETCH_DIM_IS
         || opline->opcode == ZEND_FETCH_DIM_UNSET
         || opline->opcode == ZEND_FETCH_LIST_R) {
          UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        } else {
          /* invalid key type */
          return SUCCESS;
        }
        COPY_SSA_OBJ_TYPE(ssa_op->op1_use, ssa_op->op1_def);
      }
      /* FETCH_LIST on a string behaves like FETCH_R on null */
      tmp = zend_array_element_type(
        opline->opcode != ZEND_FETCH_LIST_R ? t1 : ((t1 & ~MAY_BE_STRING) | MAY_BE_NULL),
        opline->op1_type,
        opline->opcode != ZEND_FETCH_DIM_R && opline->opcode != ZEND_FETCH_DIM_IS
          && opline->opcode != ZEND_FETCH_LIST_R,
        opline->op2_type == IS_UNUSED);
      if (opline->opcode == ZEND_FETCH_DIM_FUNC_ARG && (t1 & (MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_RESOURCE))) {
        tmp |= MAY_BE_NULL;
      }
      if (opline->opcode == ZEND_FETCH_DIM_IS && (t1 & MAY_BE_STRING)) {
        tmp |= MAY_BE_NULL;
      }
      if ((tmp & (MAY_BE_RC1|MAY_BE_RCN)) == MAY_BE_RCN && opline->result_type == IS_TMP_VAR) {
        /* refcount may be indirectly decremented. Make an exception if the result is used in the next instruction */
        if (!ssa_opcodes) {
          if (ssa->vars[ssa_op->result_def].use_chain < 0
           || opline + 1 != op_array->opcodes + ssa->vars[ssa_op->result_def].use_chain) {
            tmp |= MAY_BE_RC1;
            }
        } else {
          if (ssa->vars[ssa_op->result_def].use_chain < 0
           || opline + 1 != ssa_opcodes[ssa->vars[ssa_op->result_def].use_chain]) {
            tmp |= MAY_BE_RC1;
            }
        }
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    case ZEND_FETCH_THIS:
      if (!(op_array->fn_flags & ZEND_ACC_TRAIT_CLONE)) {
        UPDATE_SSA_OBJ_TYPE(op_array->scope, 1, ssa_op->result_def);
      }
      UPDATE_SSA_TYPE(MAY_BE_RCN|MAY_BE_OBJECT, ssa_op->result_def);
      break;
    case ZEND_FETCH_OBJ_R:
    case ZEND_FETCH_OBJ_IS:
    case ZEND_FETCH_OBJ_RW:
    case ZEND_FETCH_OBJ_W:
    case ZEND_FETCH_OBJ_UNSET:
    case ZEND_FETCH_OBJ_FUNC_ARG:
      if (ssa_op->result_def >= 0) {
        uint32_t tmp = 0;
        ce = NULL;
        if (opline->op1_type != IS_UNUSED
            && (t1 & (MAY_BE_ANY | MAY_BE_UNDEF) & ~MAY_BE_OBJECT)) {
          tmp |= MAY_BE_NULL;
        }
        if (opline->op1_type == IS_UNUSED || (t1 & MAY_BE_OBJECT)) {
          const zend_property_info *prop_info = zend_fetch_prop_info(op_array, ssa, opline, ssa_op);
          tmp |= zend_fetch_prop_type(script, prop_info, &ce);
          if (opline->opcode != ZEND_FETCH_OBJ_R && opline->opcode != ZEND_FETCH_OBJ_IS) {
            tmp |= MAY_BE_REF | MAY_BE_INDIRECT;
            if ((opline->extended_value & ZEND_FETCH_OBJ_FLAGS) == ZEND_FETCH_DIM_WRITE) {
              tmp |= MAY_BE_UNDEF;
            }
            ce = NULL;
          } else if (!(opline->op1_type & (IS_VAR|IS_TMP_VAR)) || !(t1 & MAY_BE_RC1)) {
            const zend_class_entry *ce = NULL;

            if (opline->op1_type == IS_UNUSED) {
              ce = op_array->scope;
            } else if (ssa_op->op1_use >= 0 && !ssa->var_info[ssa_op->op1_use].is_instanceof) {
              ce = ssa->var_info[ssa_op->op1_use].ce;
            }
            /* Unset properties will resort back to __get/__set */
            if (ce
             && !ce->create_object
             && ce->default_object_handlers->read_property == zend_std_read_property
             && !ce->__get
             && !result_may_be_separated(ssa, ssa_op)) {
              tmp &= ~MAY_BE_RC1;
            }
            if (opline->opcode == ZEND_FETCH_OBJ_IS) {
              /* IS check may return null for uninitialized typed property. */
              tmp |= MAY_BE_NULL;
            }
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
        if (ce) {
          UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->result_def);
        }
      }
      break;
    case ZEND_FETCH_STATIC_PROP_R:
    case ZEND_FETCH_STATIC_PROP_IS:
    case ZEND_FETCH_STATIC_PROP_RW:
    case ZEND_FETCH_STATIC_PROP_W:
    case ZEND_FETCH_STATIC_PROP_UNSET:
    case ZEND_FETCH_STATIC_PROP_FUNC_ARG:
      tmp = zend_fetch_prop_type(script,
        zend_fetch_static_prop_info(script, op_array, ssa, opline), &ce);
      if (opline->opcode != ZEND_FETCH_STATIC_PROP_R
          && opline->opcode != ZEND_FETCH_STATIC_PROP_IS) {
        tmp |= MAY_BE_REF | MAY_BE_INDIRECT;
        if ((opline->extended_value & ZEND_FETCH_OBJ_FLAGS) == ZEND_FETCH_DIM_WRITE) {
          tmp |= MAY_BE_UNDEF;
        }
        ce = NULL;
      } else {
        if (!result_may_be_separated(ssa, ssa_op)) {
          tmp &= ~MAY_BE_RC1;
        }
        if (opline->opcode == ZEND_FETCH_STATIC_PROP_IS) {
          tmp |= MAY_BE_NULL;
        }
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      if (ce) {
        UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->result_def);
      }
      break;
    case ZEND_FRAMELESS_ICALL_1:
    case ZEND_FRAMELESS_ICALL_2:
    case ZEND_FRAMELESS_ICALL_3:
      if (ssa_op->op1_def >= 0) {
        ZEND_ASSERT(ssa_op->op1_use >= 0);
        tmp = ssa->var_info[ssa_op->op1_use].type;
        if (tmp & MAY_BE_RC1) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      if (ssa_op->op2_def >= 0) {
        ZEND_ASSERT(ssa_op->op2_use >= 0);
        tmp = ssa->var_info[ssa_op->op2_use].type;
        if (tmp & MAY_BE_RC1) {
          tmp |= MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->op2_def);
      }
      if (opline->opcode == ZEND_FRAMELESS_ICALL_3) {
        zend_ssa_op *next_ssa_op = ssa_op + 1;
        if (next_ssa_op->op1_def >= 0) {
          ZEND_ASSERT(next_ssa_op->op1_use >= 0);
          tmp = ssa->var_info[next_ssa_op->op1_use].type;
          if (tmp & MAY_BE_RC1) {
            tmp |= MAY_BE_RCN;
          }
          UPDATE_SSA_TYPE(tmp, next_ssa_op->op1_def);
        }
      }
      ZEND_FALLTHROUGH;
    case ZEND_FRAMELESS_ICALL_0:
    case ZEND_DO_FCALL:
    case ZEND_DO_ICALL:
    case ZEND_DO_UCALL:
    case ZEND_DO_FCALL_BY_NAME:
      if (ssa_op->result_def >= 0) {
        zend_func_info *func_info = ZEND_FUNC_INFO(op_array);
        zend_call_info *call_info;

        if (!func_info || !func_info->call_map) {
          goto unknown_opcode;
        }
        call_info = func_info->call_map[opline - op_array->opcodes];
        if (!call_info) {
          goto unknown_opcode;
        }

        zend_class_entry *ce;
        bool ce_is_instanceof;
        tmp = zend_get_func_info(call_info, ssa, &ce, &ce_is_instanceof);
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
        if (ce) {
          UPDATE_SSA_OBJ_TYPE(ce, ce_is_instanceof, ssa_op->result_def);
        }
      }
      break;
    case ZEND_CALLABLE_CONVERT:
      UPDATE_SSA_TYPE(MAY_BE_OBJECT | MAY_BE_RC1 | MAY_BE_RCN, ssa_op->result_def);
      UPDATE_SSA_OBJ_TYPE(zend_ce_closure, /* is_instanceof */ false, ssa_op->result_def);
      break;
    case ZEND_FETCH_CONSTANT:
      UPDATE_SSA_TYPE(MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ANY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY, ssa_op->result_def);
      break;
    case ZEND_FETCH_CLASS_CONSTANT: {
      bool is_prototype;
      const zend_class_constant *cc = zend_fetch_class_const_info(script, op_array, opline, &is_prototype);
      if (!cc || !ZEND_TYPE_IS_SET(cc->type)) {
        UPDATE_SSA_TYPE(MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ANY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY, ssa_op->result_def);
        break;
      }
      UPDATE_SSA_TYPE(zend_convert_type(script, cc->type, &ce), ssa_op->result_def);
      if (ce) {
        UPDATE_SSA_OBJ_TYPE(ce, /* is_instanceof */ true, ssa_op->result_def);
      }
      break;
    }
    case ZEND_STRLEN:
    case ZEND_COUNT:
    case ZEND_FUNC_NUM_ARGS:
      UPDATE_SSA_TYPE(MAY_BE_LONG, ssa_op->result_def);
      break;
    case ZEND_FUNC_GET_ARGS:
      UPDATE_SSA_TYPE(MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ARRAY|MAY_BE_ARRAY_EMPTY|MAY_BE_ARRAY_PACKED|MAY_BE_ARRAY_OF_ANY, ssa_op->result_def);
      break;
    case ZEND_GET_CLASS:
    case ZEND_GET_CALLED_CLASS:
      UPDATE_SSA_TYPE(MAY_BE_STRING|MAY_BE_RCN, ssa_op->result_def);
      break;
    case ZEND_GET_TYPE:
      UPDATE_SSA_TYPE(MAY_BE_STRING|MAY_BE_RC1|MAY_BE_RCN, ssa_op->result_def);
      break;
    case ZEND_TYPE_CHECK: {
      uint32_t expected_type_mask = opline->extended_value;
      if (t1 & MAY_BE_UNDEF) {
        t1 |= MAY_BE_NULL;
      }
      tmp = 0;
      if (t1 & expected_type_mask) {
        tmp |= MAY_BE_TRUE;
        if ((t1 & expected_type_mask) & MAY_BE_RESOURCE) {
          tmp |= MAY_BE_FALSE;
        }
      }
      if (t1 & (MAY_BE_ANY - expected_type_mask)) {
        tmp |= MAY_BE_FALSE;
      }
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      break;
    }
    case ZEND_DEFINED:
      UPDATE_SSA_TYPE(MAY_BE_FALSE|MAY_BE_TRUE, ssa_op->result_def);
      break;
    case ZEND_VERIFY_RETURN_TYPE:
      if (t1 & MAY_BE_REF) {
        tmp = t1;
        ce = NULL;
      } else {
        zend_arg_info *ret_info = op_array->arg_info - 1;
        tmp = zend_fetch_arg_info_type(script, ret_info, &ce);
        if ((tmp & MAY_BE_NULL) && opline->op1_type == IS_CV) {
          tmp |= MAY_BE_UNDEF;
        }
        tmp |= (t1 & MAY_BE_INDIRECT);

        // TODO: We could model more precisely how illegal types are converted.
        uint32_t extra_types = t1 & ~tmp;
        if (!extra_types) {
          tmp &= t1;
        }
      }
      if (opline->op1_type & (IS_TMP_VAR|IS_VAR|IS_CV)) {
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
        if (ce) {
          UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->op1_def);
        } else {
          UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->op1_def);
        }
      } else {
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
        if (ce) {
          UPDATE_SSA_OBJ_TYPE(ce, 1, ssa_op->result_def);
        } else {
          UPDATE_SSA_OBJ_TYPE(NULL, 0, ssa_op->result_def);
        }
      }
      break;
    case ZEND_MAKE_REF:
      tmp = MAY_BE_REF|MAY_BE_RC1|MAY_BE_RCN|MAY_BE_ANY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF;
      UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      if (ssa_op->op1_def >= 0) {
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
      break;
    case ZEND_CATCH:
      /* Forbidden opcodes */
      ZEND_UNREACHABLE();
      break;
    case ZEND_FETCH_CLASS_NAME:
      UPDATE_SSA_TYPE(MAY_BE_STRING|MAY_BE_RCN, ssa_op->result_def);
      break;
    case ZEND_ISSET_ISEMPTY_THIS:
      UPDATE_SSA_TYPE(MAY_BE_BOOL, ssa_op->result_def);
      break;
    case ZEND_DECLARE_LAMBDA_FUNCTION:
      UPDATE_SSA_TYPE(MAY_BE_OBJECT|MAY_BE_RC1|MAY_BE_RCN, ssa_op->result_def);
      UPDATE_SSA_OBJ_TYPE(zend_ce_closure, /* is_instanceof */ false, ssa_op->result_def);
      break;
    case ZEND_PRE_DEC_STATIC_PROP:
    case ZEND_PRE_INC_STATIC_PROP:
    case ZEND_POST_DEC_STATIC_PROP:
    case ZEND_POST_INC_STATIC_PROP: {
      if (ssa_op->result_def >= 0) {
        const zend_property_info *prop_info = zend_fetch_static_prop_info(script, op_array, ssa, opline);
        zend_class_entry *prop_ce;
        tmp = zend_fetch_prop_type(script, prop_info, &prop_ce);
        /* Internal objects may result in essentially anything. */
        if (tmp & MAY_BE_OBJECT) {
          goto unknown_opcode;
        }
        tmp &= MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_STRING|MAY_BE_BOOL|MAY_BE_NULL;
        if (tmp & MAY_BE_STRING) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
    }
    case ZEND_SPACESHIP:
      UPDATE_SSA_TYPE(MAY_BE_LONG, ssa_op->result_def);
      break;
    case ZEND_FETCH_GLOBALS:
      UPDATE_SSA_TYPE(MAY_BE_ARRAY|MAY_BE_ARRAY_KEY_ANY|MAY_BE_ARRAY_OF_ANY|MAY_BE_ARRAY_OF_REF|MAY_BE_RC1|MAY_BE_RCN, ssa_op->result_def);
      break;
    default:
#ifdef ZEND_DEBUG_TYPE_INFERENCE
      if (ssa_op->result_def >= 0) {
        switch (opline->opcode) {
          case ZEND_FETCH_R:
          case ZEND_FETCH_W:
          case ZEND_FETCH_RW:
          case ZEND_FETCH_IS:
          case ZEND_FETCH_UNSET:
          case ZEND_YIELD_FROM:
          /* Currently unimplemented due to some assumptions in JIT. See:
           * https://github.com/php/php-src/pull/13304#issuecomment-1926668141 */
          case ZEND_SEPARATE:
            break;
          default:
            fprintf(stderr, "Missing result type inference for opcode %s, line %d\n", zend_get_opcode_name(opline->opcode), opline->lineno);
            break;
        }
      }
      if (ssa_op->op1_def >= 0) {
        fprintf(stderr, "Missing op1 type inference for opcode %s, line %d\n", zend_get_opcode_name(opline->opcode), opline->lineno);
      }
      if (ssa_op->op2_def >= 0) {
        fprintf(stderr, "Missing op2 type inference for opcode %s, line %d\n", zend_get_opcode_name(opline->opcode), opline->lineno);
      }
#endif
      if (ssa_op->op1_def >= 0) {
        tmp = MAY_BE_ANY | MAY_BE_REF | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        UPDATE_SSA_TYPE(tmp, ssa_op->op1_def);
      }
unknown_opcode:
      if (ssa_op->result_def >= 0) {
        tmp = MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
        if (opline->result_type == IS_TMP_VAR) {
          if (opline->opcode == ZEND_FETCH_R || opline->opcode == ZEND_FETCH_IS) {
            /* Variable reference counter may be decremented before use */
            /* See: ext/opcache/tests/jit/fetch_r_001.phpt */
            tmp |= MAY_BE_RC1 | MAY_BE_RCN;
          } else {
            tmp |= MAY_BE_RC1 | MAY_BE_RCN;
          }
        } else if (opline->result_type == IS_CV) {
          tmp |= MAY_BE_RC1 | MAY_BE_RCN;
        } else {
          tmp |= MAY_BE_REF | MAY_BE_RC1 | MAY_BE_RCN;
          switch (opline->opcode) {
            case ZEND_FETCH_W:
            case ZEND_FETCH_RW:
            case ZEND_FETCH_FUNC_ARG:
            case ZEND_FETCH_UNSET:
            case ZEND_FETCH_DIM_W:
            case ZEND_FETCH_DIM_RW:
            case ZEND_FETCH_DIM_FUNC_ARG:
            case ZEND_FETCH_DIM_UNSET:
            case ZEND_FETCH_OBJ_W:
            case ZEND_FETCH_OBJ_RW:
            case ZEND_FETCH_OBJ_FUNC_ARG:
            case ZEND_FETCH_OBJ_UNSET:
            case ZEND_FETCH_STATIC_PROP_W:
            case ZEND_FETCH_STATIC_PROP_RW:
            case ZEND_FETCH_STATIC_PROP_FUNC_ARG:
            case ZEND_FETCH_STATIC_PROP_UNSET:
              tmp |= MAY_BE_INDIRECT;
              break;
          }
        }
        UPDATE_SSA_TYPE(tmp, ssa_op->result_def);
      }
      break;
  }

  return SUCCESS;
}

ZEND_API zend_result zend_update_type_info(
      const zend_op_array *op_array,
      zend_ssa            *ssa,
      const zend_script   *script,
      const zend_op       *opline,
      zend_ssa_op         *ssa_op,
      const zend_op      **ssa_opcodes,
      zend_long            optimization_level)
{
  return _zend_update_type_info(op_array, ssa, script, NULL, opline, ssa_op, ssa_opcodes, optimization_level,
              false);
}

static uint32_t get_class_entry_rank(const zend_class_entry *ce) {
  uint32_t rank = 0;
  if (ce->ce_flags & ZEND_ACC_LINKED) {
    while (ce->parent) {
      rank++;
      ce = ce->parent;
    }
  }
  return rank;
}

/* Compute least common ancestor on class inheritance tree only */
static zend_class_entry *join_class_entries(
    zend_class_entry *ce1, zend_class_entry *ce2, bool *is_instanceof) {
  uint32_t rank1, rank2;
  if (ce1 == ce2) {
    return ce1;
  }
  if (!ce1 || !ce2) {
    return NULL;
  }

  rank1 = get_class_entry_rank(ce1);
  rank2 = get_class_entry_rank(ce2);

  while (rank1 != rank2) {
    if (rank1 > rank2) {
      ce1 = !(ce1->ce_flags & ZEND_ACC_LINKED) ? NULL : ce1->parent;
      rank1--;
    } else {
      ce2 = !(ce2->ce_flags & ZEND_ACC_LINKED) ? NULL : ce2->parent;
      rank2--;
    }
  }

  while (ce1 != ce2) {
    ce1 = !(ce1->ce_flags & ZEND_ACC_LINKED) ? NULL : ce1->parent;
    ce2 = !(ce2->ce_flags & ZEND_ACC_LINKED) ? NULL : ce2->parent;
  }

  if (ce1) {
    *is_instanceof = true;
  }
  return ce1;
}

static bool safe_instanceof(const zend_class_entry *ce1, const zend_class_entry *ce2) {
  if (ce1 == ce2) {
    return 1;
  }
  if (!(ce1->ce_flags & ZEND_ACC_LINKED)) {
    /* This case could be generalized, similarly to unlinked_instanceof */
    return 0;
  }
  return instanceof_function(ce1, ce2);
}

static zend_result zend_infer_types_ex(const zend_op_array *op_array, const zend_script *script, zend_ssa *ssa, zend_bitset worklist, zend_long optimization_level)
{
  const zend_basic_block *blocks = ssa->cfg.blocks;
  zend_ssa_var *ssa_vars = ssa->vars;
  zend_ssa_var_info *ssa_var_info = ssa->var_info;
  int ssa_vars_count = ssa->vars_count;
  int j;
  uint32_t tmp, worklist_len = zend_bitset_len(ssa_vars_count);
  bool update_worklist = 1;
  const zend_op **ssa_opcodes = NULL;

  while (!zend_bitset_empty(worklist, worklist_len)) {
    j = zend_bitset_first(worklist, worklist_len);
    zend_bitset_excl(worklist, j);
    if (ssa_vars[j].definition_phi) {
      zend_ssa_phi *p = ssa_vars[j].definition_phi;
      if (p->pi >= 0) {
        zend_class_entry *ce = ssa_var_info[p->sources[0]].ce;
        bool is_instanceof = ssa_var_info[p->sources[0]].is_instanceof;
        tmp = get_ssa_var_info(ssa, p->sources[0]);

        if (!p->has_range_constraint) {
          const zend_ssa_type_constraint *constraint = &p->constraint.type;
          tmp &= constraint->type_mask;
          if (!(tmp & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE))) {
            tmp &= ~(MAY_BE_RC1|MAY_BE_RCN);
          }
          if ((tmp & MAY_BE_OBJECT) && constraint->ce && ce != constraint->ce) {
            if (!ce) {
              ce = constraint->ce;
              is_instanceof = true;
            } else if (is_instanceof && safe_instanceof(constraint->ce, ce)) {
              ce = constraint->ce;
            } else {
              /* Ignore the constraint (either ce instanceof constraint->ce or
               * they are unrelated, as far as we can statically determine) */
            }
          }
        }

        UPDATE_SSA_TYPE(tmp, j);
        if (tmp & MAY_BE_REF) {
          UPDATE_SSA_OBJ_TYPE(NULL, 0, j);
        } else {
          UPDATE_SSA_OBJ_TYPE(ce, is_instanceof, j);
        }
      } else {
        bool first = true;
        bool is_instanceof = false;
        zend_class_entry *ce = NULL;
        uint32_t i;

        tmp = 0;
        for (i = 0; i < blocks[p->block].predecessors_count; i++) {
          tmp |= get_ssa_var_info(ssa, p->sources[i]);
        }
        UPDATE_SSA_TYPE(tmp, j);
        for (i = 0; i < blocks[p->block].predecessors_count; i++) {
          zend_ssa_var_info *info;

          ZEND_ASSERT(p->sources[i] >= 0);
          info = &ssa_var_info[p->sources[i]];
          if (info->type & MAY_BE_OBJECT) {
            if (first) {
              ce = info->ce;
              is_instanceof = info->is_instanceof;
              first = false;
            } else {
              is_instanceof |= info->is_instanceof;
              ce = join_class_entries(ce, info->ce, &is_instanceof);
            }
          }
        }
        UPDATE_SSA_OBJ_TYPE(ce, ce ? is_instanceof : 0, j);
      }
    } else if (ssa_vars[j].definition >= 0) {
      int i = ssa_vars[j].definition;
      if (_zend_update_type_info(op_array, ssa, script, worklist, op_array->opcodes + i, ssa->ops + i, NULL, optimization_level, true) == FAILURE) {
        return FAILURE;
      }
    }
  }
  return SUCCESS;
}

static bool is_narrowable_instr(const zend_op *opline)  {
  return opline->opcode == ZEND_ADD || opline->opcode == ZEND_SUB
    || opline->opcode == ZEND_MUL || opline->opcode == ZEND_DIV;
}

static bool is_effective_op1_double_cast(const zend_op *opline, const zval *op2) {
  return (opline->opcode == ZEND_ADD && Z_LVAL_P(op2) == 0)
    || (opline->opcode == ZEND_SUB && Z_LVAL_P(op2) == 0)
    || (opline->opcode == ZEND_MUL && Z_LVAL_P(op2) == 1)
    || (opline->opcode == ZEND_DIV && Z_LVAL_P(op2) == 1);
}
static bool is_effective_op2_double_cast(const zend_op *opline, const zval *op1) {
  /* In PHP it holds that (double)(0-$int) is bitwise identical to 0.0-(double)$int,
   * so allowing SUB here is fine. */
  return (opline->opcode == ZEND_ADD && Z_LVAL_P(op1) == 0)
    || (opline->opcode == ZEND_SUB && Z_LVAL_P(op1) == 0)
    || (opline->opcode == ZEND_MUL && Z_LVAL_P(op1) == 1);
}

/* This function recursively checks whether it's possible to convert an integer variable
 * initialization to a double initialization. The basic idea is that if the value is used
 * only in add/sub/mul/div ("narrowable" instructions) with a double result value, then it
 * will be cast to double at that point anyway, so we may as well do it earlier already.
 *
 * The tricky case are chains of operations, where it's not necessarily a given that converting
 * an integer to double before the chain of operations is the same as converting it after the
 * chain. What this function does is detect two cases where it is safe:
 *  * If the operations only involve constants, then we can simply verify that performing the
 *    calculation on integers and doubles yields the same value.
 *  * Even if one operand is not known, we may be able to determine that the operations with the
 *    integer replaced by a double only acts as an effective double cast on the unknown operand.
 *    E.g. 0+$i and 0.0+$i only differ by that cast. If then the consuming instruction of this
 *    result will perform a double cast anyway, the conversion is safe.
 *
 * The checks happens recursively, while keeping track of which variables are already visited to
 * avoid infinite loops. An iterative, worklist driven approach would be possible, but the state
 * management more cumbersome to implement, so we don't bother for now.
 */
static bool can_convert_to_double(
    const zend_op_array *op_array, zend_ssa *ssa, int var_num,
    zval *value, zend_bitset visited) {
  zend_ssa_var *var = &ssa->vars[var_num];
  zend_ssa_phi *phi;
  int use;
  uint32_t type;

  if (zend_bitset_in(visited, var_num)) {
    return 1;
  }
  zend_bitset_incl(visited, var_num);

  for (use = var->use_chain; use >= 0; use = zend_ssa_next_use(ssa->ops, var_num, use)) {
    zend_op *opline = &op_array->opcodes[use];
    zend_ssa_op *ssa_op = &ssa->ops[use];

    if (zend_ssa_is_no_val_use(opline, ssa_op, var_num)) {
      continue;
    }

    if (!is_narrowable_instr(opline)) {
      return 0;
    }

    /* Instruction always returns double, the conversion is certainly fine */
    type = ssa->var_info[ssa_op->result_def].type;
    if ((type & MAY_BE_ANY) == MAY_BE_DOUBLE) {
      continue;
    }

    /* UNDEF signals that the previous result is an effective double cast, this is only allowed
     * if this instruction would have done the cast anyway (previous check). */
    if (Z_ISUNDEF_P(value)) {
      return 0;
    }

    /* Check that narrowing can actually be useful */
    if ((type & MAY_BE_ANY) & ~(MAY_BE_LONG|MAY_BE_DOUBLE)) {
      return 0;
    }

    {
      /* For calculation on original values */
      zval orig_op1, orig_op2, orig_result;
      /* For calculation with var_num cast to double */
      zval dval_op1, dval_op2, dval_result;

      ZVAL_UNDEF(&orig_op1);
      ZVAL_UNDEF(&dval_op1);
      if (ssa_op->op1_use == var_num) {
        ZVAL_COPY_VALUE(&orig_op1, value);
        ZVAL_DOUBLE(&dval_op1, (double) Z_LVAL_P(value));
      } else if (opline->op1_type == IS_CONST) {
        zval *zv = CRT_CONSTANT(opline->op1);
        if (Z_TYPE_P(zv) == IS_LONG || Z_TYPE_P(zv) == IS_DOUBLE) {
          ZVAL_COPY_VALUE(&orig_op1, zv);
          ZVAL_COPY_VALUE(&dval_op1, zv);
        }
      }

      ZVAL_UNDEF(&orig_op2);
      ZVAL_UNDEF(&dval_op2);
      if (ssa_op->op2_use == var_num) {
        ZVAL_COPY_VALUE(&orig_op2, value);
        ZVAL_DOUBLE(&dval_op2, (double) Z_LVAL_P(value));
      } else if (opline->op2_type == IS_CONST) {
        zval *zv = CRT_CONSTANT(opline->op2);
        if (Z_TYPE_P(zv) == IS_LONG || Z_TYPE_P(zv) == IS_DOUBLE) {
          ZVAL_COPY_VALUE(&orig_op2, zv);
          ZVAL_COPY_VALUE(&dval_op2, zv);
        }
      }

      ZEND_ASSERT(!Z_ISUNDEF(orig_op1) || !Z_ISUNDEF(orig_op2));
      if (Z_ISUNDEF(orig_op1)) {
        if (opline->opcode == ZEND_MUL && Z_LVAL(orig_op2) == 0) {
          ZVAL_LONG(&orig_result, 0);
        } else if (is_effective_op1_double_cast(opline, &orig_op2)) {
          ZVAL_UNDEF(&orig_result);
        } else {
          return 0;
        }
      } else if (Z_ISUNDEF(orig_op2)) {
        if (opline->opcode == ZEND_MUL && Z_LVAL(orig_op1) == 0) {
          ZVAL_LONG(&orig_result, 0);
        } else if (is_effective_op2_double_cast(opline, &orig_op1)) {
          ZVAL_UNDEF(&orig_result);
        } else {
          return 0;
        }
      } else {
        uint8_t opcode = opline->opcode;

        if (opcode == ZEND_ASSIGN_OP) {
          opcode = opline->extended_value;
        }

        /* Avoid division by zero */
        if (opcode == ZEND_DIV && zval_get_double(&orig_op2) == 0.0) {
          return 0;
        }

        get_binary_op(opcode)(&orig_result, &orig_op1, &orig_op2);
        get_binary_op(opcode)(&dval_result, &dval_op1, &dval_op2);
        ZEND_ASSERT(Z_TYPE(dval_result) == IS_DOUBLE);
        if (zval_get_double(&orig_result) != Z_DVAL(dval_result)) {
          return 0;
        }
      }

      if (!can_convert_to_double(op_array, ssa, ssa_op->result_def, &orig_result, visited)) {
        return 0;
      }
    }
  }

  for (phi = var->phi_use_chain; phi; phi = zend_ssa_next_use_phi(ssa, var_num, phi)) {
    /* Check that narrowing can actually be useful */
    type = ssa->var_info[phi->ssa_var].type;
    if ((type & MAY_BE_ANY) & ~(MAY_BE_LONG|MAY_BE_DOUBLE)) {
      return 0;
    }

    if (!can_convert_to_double(op_array, ssa, phi->ssa_var, value, visited)) {
      return 0;
    }
  }

  return 1;
}

static zend_result zend_type_narrowing(const zend_op_array *op_array, const zend_script *script, zend_ssa *ssa, zend_long optimization_level)
{
  uint32_t bitset_len = zend_bitset_len(ssa->vars_count);
  zend_bitset visited, worklist;
  int i, v;
  zend_op *opline;
  bool narrowed = 0;
  ALLOCA_FLAG(use_heap)

  visited = ZEND_BITSET_ALLOCA(2 * bitset_len, use_heap);
  worklist = visited + bitset_len;

  zend_bitset_clear(worklist, bitset_len);

  for (v = op_array->last_var; v < ssa->vars_count; v++) {
    if ((ssa->var_info[v].type & (MAY_BE_REF | MAY_BE_ANY | MAY_BE_UNDEF)) != MAY_BE_LONG) continue;
    if (ssa->vars[v].definition < 0) continue;
    if (ssa->vars[v].no_val) continue;
    opline = op_array->opcodes + ssa->vars[v].definition;
    /* Go through assignments of literal integers and check if they can be converted to
     * doubles instead, in the hope that we'll narrow long|double to double. */
    if (opline->opcode == ZEND_ASSIGN && opline->result_type == IS_UNUSED &&
        opline->op1_type == IS_CV && opline->op2_type == IS_CONST) {
      zval *value = CRT_CONSTANT(opline->op2);

      zend_bitset_clear(visited, bitset_len);
      if (can_convert_to_double(op_array, ssa, v, value, visited)) {
        narrowed = 1;
        ssa->var_info[v].use_as_double = 1;
        /* The "visited" vars are exactly those which may change their type due to
         * narrowing. Reset their types and add them to the type inference worklist */
        ZEND_BITSET_FOREACH(visited, bitset_len, i) {
          ssa->var_info[i].type &= ~MAY_BE_ANY;
        } ZEND_BITSET_FOREACH_END();
        zend_bitset_union(worklist, visited, bitset_len);
      }
    }
  }

  if (!narrowed) {
    free_alloca(visited, use_heap);
    return SUCCESS;
  }

  if (zend_infer_types_ex(op_array, script, ssa, worklist, optimization_level) == FAILURE) {
    free_alloca(visited, use_heap);
    return FAILURE;
  }

  free_alloca(visited, use_heap);
  return SUCCESS;
}

static bool is_recursive_tail_call(const zend_op_array *op_array, const zend_op *opline)
{
  const zend_func_info *info = ZEND_FUNC_INFO(op_array);

  if (info->ssa.ops && info->ssa.vars && info->call_map &&
      info->ssa.ops[opline - op_array->opcodes].op1_use >= 0 &&
      info->ssa.vars[info->ssa.ops[opline - op_array->opcodes].op1_use].definition >= 0) {

    const zend_op *op = op_array->opcodes + info->ssa.vars[info->ssa.ops[opline - op_array->opcodes].op1_use].definition;

    if (op->opcode == ZEND_DO_UCALL) {
      const zend_call_info *call_info = info->call_map[op - op_array->opcodes];
      if (call_info && op_array == &call_info->callee_func->op_array) {
        return 1;
      }
    }
  }
  return 0;
}

uint32_t zend_get_return_info_from_signature_only(
    const zend_function *func, const zend_script *script,
    zend_class_entry **ce, bool *ce_is_instanceof, bool use_tentative_return_info) {
  uint32_t type;
  if (func->common.fn_flags & ZEND_ACC_HAS_RETURN_TYPE &&
    (use_tentative_return_info || !ZEND_ARG_TYPE_IS_TENTATIVE(func->common.arg_info - 1))
  ) {
    const zend_arg_info *ret_info = func->common.arg_info - 1;
    type = zend_fetch_arg_info_type(script, ret_info, ce);
    *ce_is_instanceof = ce != NULL;
  } else {
    type = MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF
      | MAY_BE_RC1 | MAY_BE_RCN;
    *ce = NULL;
    *ce_is_instanceof = false;
  }

  /* For generators RETURN_REFERENCE refers to the yielded values. */
  if ((func->common.fn_flags & ZEND_ACC_RETURN_REFERENCE)
      && !(func->common.fn_flags & ZEND_ACC_GENERATOR)) {
    type |= MAY_BE_REF;
    *ce = NULL;
    *ce_is_instanceof = false;
  }
  return type;
}

ZEND_API void zend_init_func_return_info(
  const zend_op_array *op_array, const zend_script *script, zend_ssa_var_info *ret)
{
  ZEND_ASSERT((op_array->fn_flags & ZEND_ACC_HAS_RETURN_TYPE));

  zend_ssa_range tmp_range = {0, 0, 0, 0};
  bool is_instanceof = false;
  ret->type = zend_get_return_info_from_signature_only(
    (zend_function *) op_array, script, &ret->ce, &is_instanceof, /* use_tentative_return_info */ true);
  ret->is_instanceof = is_instanceof;
  ret->range = tmp_range;
  ret->has_range = 0;
}

static void zend_func_return_info(const zend_op_array   *op_array,
                                  const zend_script     *script,
                                  bool                   recursive,
                                  bool                   widening,
                                  zend_ssa_var_info     *ret)
{
  const zend_func_info *info = ZEND_FUNC_INFO(op_array);
  const zend_ssa *ssa = &info->ssa;
  uint32_t blocks_count = info->ssa.cfg.blocks_count;
  const zend_basic_block *blocks = info->ssa.cfg.blocks;
  uint32_t t1;
  uint32_t tmp = 0;
  zend_class_entry *tmp_ce = NULL;
  int tmp_is_instanceof = -1;
  zend_class_entry *arg_ce;
  bool arg_is_instanceof;
  zend_ssa_range tmp_range = {0, 0, 0, 0};
  int tmp_has_range = -1;

  if (op_array->fn_flags & ZEND_ACC_GENERATOR) {
    ret->type = MAY_BE_OBJECT | MAY_BE_RC1 | MAY_BE_RCN;
    ret->ce = zend_ce_generator;
    ret->is_instanceof = 0;
    ret->range = tmp_range;
    ret->has_range = 0;
    return;
  }

  if (!ret->type) {
    /* We will intersect the type later. */
    ret->type = MAY_BE_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF | MAY_BE_ARRAY_KEY_ANY
      | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_REF;
  }

  for (uint32_t j = 0; j < blocks_count; j++) {
    if ((blocks[j].flags & ZEND_BB_REACHABLE) && blocks[j].len != 0) {
      zend_op *opline = op_array->opcodes + blocks[j].start + blocks[j].len - 1;

      if (opline->opcode == ZEND_RETURN || opline->opcode == ZEND_RETURN_BY_REF) {
        const zend_ssa_op *ssa_op = ssa->ops ? &ssa->ops[opline - op_array->opcodes] : NULL;
        if (!recursive && ssa_op && info->ssa.var_info &&
            ssa_op->op1_use >= 0 &&
            info->ssa.var_info[ssa_op->op1_use].recursive) {
          continue;
        }
        if (is_recursive_tail_call(op_array, opline)) {
          continue;
        }
        t1 = OP1_INFO();
        if (t1 & MAY_BE_UNDEF) {
          t1 |= MAY_BE_NULL;
        }
        if (opline->opcode == ZEND_RETURN) {
          if (t1 & MAY_BE_RC1) {
            t1 |= MAY_BE_RCN;
          }
          t1 &= ~(MAY_BE_UNDEF | MAY_BE_REF);
        } else {
          t1 |= MAY_BE_REF;
          t1 &= ~(MAY_BE_UNDEF | MAY_BE_RC1 | MAY_BE_RCN);
        }
        tmp |= t1;

        if (ssa_op && info->ssa.var_info &&
            ssa_op->op1_use >= 0 && !(t1 & MAY_BE_REF) &&
            info->ssa.var_info[ssa_op->op1_use].ce) {
          arg_ce = info->ssa.var_info[ssa_op->op1_use].ce;
          arg_is_instanceof = info->ssa.var_info[ssa_op->op1_use].is_instanceof;
        } else {
          arg_ce = NULL;
          arg_is_instanceof = false;
        }

        if (tmp_is_instanceof < 0) {
          tmp_ce = arg_ce;
          tmp_is_instanceof = arg_is_instanceof;
        } else if (arg_ce && arg_ce == tmp_ce) {
          if (tmp_is_instanceof != arg_is_instanceof) {
            tmp_is_instanceof = 1;
          }
        } else {
          tmp_ce = NULL;
          tmp_is_instanceof = 0;
        }

        if (opline->op1_type == IS_CONST) {
          const zval *zv = CRT_CONSTANT(opline->op1);

          if (Z_TYPE_P(zv) == IS_LONG) {
            if (tmp_has_range < 0) {
              tmp_has_range = 1;
              tmp_range.underflow = 0;
              tmp_range.min = Z_LVAL_P(zv);
              tmp_range.max = Z_LVAL_P(zv);
              tmp_range.overflow = 0;
            } else if (tmp_has_range) {
              if (!tmp_range.underflow) {
                tmp_range.min = MIN(tmp_range.min, Z_LVAL_P(zv));
              }
              if (!tmp_range.overflow) {
                tmp_range.max = MAX(tmp_range.max, Z_LVAL_P(zv));
              }
            }
          } else {
            tmp_has_range = 0;
          }
        } else if (ssa_op && info->ssa.var_info && ssa_op->op1_use >= 0) {
          if (info->ssa.var_info[ssa_op->op1_use].has_range) {
            if (tmp_has_range < 0) {
              tmp_has_range = 1;
              tmp_range = info->ssa.var_info[ssa_op->op1_use].range;
            } else if (tmp_has_range) {
              /* union */
              if (info->ssa.var_info[ssa_op->op1_use].range.underflow) {
                tmp_range.underflow = 1;
                tmp_range.min = ZEND_LONG_MIN;
              } else {
                tmp_range.min = MIN(tmp_range.min, info->ssa.var_info[ssa_op->op1_use].range.min);
              }
              if (info->ssa.var_info[ssa_op->op1_use].range.overflow) {
                tmp_range.overflow = 1;
                tmp_range.max = ZEND_LONG_MAX;
              } else {
                tmp_range.max = MAX(tmp_range.max, info->ssa.var_info[ssa_op->op1_use].range.max);
              }
            }
          } else if (!widening) {
            tmp_has_range = 1;
            tmp_range.underflow = 1;
            tmp_range.min = ZEND_LONG_MIN;
            tmp_range.max = ZEND_LONG_MAX;
            tmp_range.overflow = 1;
          }
        } else {
          tmp_has_range = 0;
        }
      }
    }
  }

  if (!(op_array->fn_flags & ZEND_ACC_HAS_RETURN_TYPE)) {
    if (tmp_is_instanceof < 0) {
      tmp_is_instanceof = 0;
      tmp_ce = NULL;
    }
    if (tmp_has_range < 0) {
      tmp_has_range = 0;
    }
    ret->ce = tmp_ce;
    ret->is_instanceof = tmp_is_instanceof;
  }
  ret->type &= tmp;
  ret->range = tmp_range;
  ret->has_range = tmp_has_range;
}

static zend_result zend_infer_types(const zend_op_array *op_array, const zend_script *script, zend_ssa *ssa, zend_long optimization_level)
{
  int ssa_vars_count = ssa->vars_count;
  int j;
  zend_bitset worklist;
  ALLOCA_FLAG(use_heap);

  worklist = do_alloca(sizeof(zend_ulong) * zend_bitset_len(ssa_vars_count), use_heap);
  memset(worklist, 0, sizeof(zend_ulong) * zend_bitset_len(ssa_vars_count));

  /* Type Inference */
  for (j = op_array->last_var; j < ssa_vars_count; j++) {
    zend_bitset_incl(worklist, j);
  }

  if (zend_infer_types_ex(op_array, script, ssa, worklist, optimization_level) == FAILURE) {
    free_alloca(worklist,  use_heap);
    return FAILURE;
  }

  if (optimization_level & ZEND_OPTIMIZER_NARROW_TO_DOUBLE) {
    /* Narrowing integer initialization to doubles */
    zend_type_narrowing(op_array, script, ssa, optimization_level);
  }

  if (ZEND_FUNC_INFO(op_array)) {
    zend_func_return_info(op_array, script, 1, 0, &ZEND_FUNC_INFO(op_array)->return_info);
  }

  free_alloca(worklist,  use_heap);
  return SUCCESS;
}

static void zend_mark_cv_references(const zend_op_array *op_array, const zend_script *script, const zend_ssa *ssa)
{
  int var, def;
  const zend_op *opline;
  zend_arg_info *arg_info;
  uint32_t worklist_len = zend_bitset_len(ssa->vars_count);
  zend_bitset worklist;
  ALLOCA_FLAG(use_heap);

  worklist = do_alloca(sizeof(zend_ulong) * worklist_len, use_heap);
  memset(worklist, 0, sizeof(zend_ulong) * worklist_len);

  /* Collect SSA variables which definitions creates PHP reference */
  for (var = 0; var < ssa->vars_count; var++) {
    def = ssa->vars[var].definition;
    if (def >= 0 && ssa->vars[var].var < op_array->last_var) {
      opline = op_array->opcodes + def;
      if (ssa->ops[def].result_def == var) {
        switch (opline->opcode) {
          case ZEND_RECV:
          case ZEND_RECV_INIT:
            arg_info = &op_array->arg_info[opline->op1.num-1];
            if (!ZEND_ARG_SEND_MODE(arg_info)) {
              continue;
            }
            break;
          default:
            continue;
        }
      } else if (ssa->ops[def].op1_def == var) {
        switch (opline->opcode) {
          case ZEND_ASSIGN_REF:
          case ZEND_MAKE_REF:
          case ZEND_FE_RESET_RW:
          case ZEND_BIND_GLOBAL:
          case ZEND_SEND_REF:
          case ZEND_SEND_VAR_EX:
          case ZEND_SEND_FUNC_ARG:
          case ZEND_BIND_INIT_STATIC_OR_JMP:
            break;
          case ZEND_INIT_ARRAY:
          case ZEND_ADD_ARRAY_ELEMENT:
            if (!(opline->extended_value & ZEND_ARRAY_ELEMENT_REF)) {
              continue;
            }
            break;
          case ZEND_BIND_STATIC:
            if (!(opline->extended_value & ZEND_BIND_REF)) {
              continue;
            }
            break;
          case ZEND_YIELD:
            if (!(op_array->fn_flags & ZEND_ACC_RETURN_REFERENCE)) {
              continue;
            }
            break;
          case ZEND_OP_DATA:
            switch ((opline-1)->opcode) {
              case ZEND_ASSIGN_OBJ_REF:
              case ZEND_ASSIGN_STATIC_PROP_REF:
                break;
              default:
                continue;
            }
            break;
          default:
            continue;
        }
      } else if (ssa->ops[def].op2_def == var) {
        switch (opline->opcode) {
          case ZEND_ASSIGN_REF:
          case ZEND_FE_FETCH_RW:
            break;
          case ZEND_BIND_LEXICAL:
            if (!(opline->extended_value & ZEND_BIND_REF)) {
              continue;
            }
            break;
          default:
            continue;
        }
      } else {
        ZEND_UNREACHABLE();
      }
      zend_bitset_incl(worklist, var);
    } else if (ssa->var_info[var].type & MAY_BE_REF) {
      zend_bitset_incl(worklist, var);
    } else if (ssa->vars[var].alias == SYMTABLE_ALIAS) {
      zend_bitset_incl(worklist, var);
    }
  }

  /* Set and propagate MAY_BE_REF */
  WHILE_WORKLIST(worklist, worklist_len, var) {

    ssa->var_info[var].type |= MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_REF | MAY_BE_ANY | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;

    if (ssa->vars[var].phi_use_chain) {
      zend_ssa_phi *p = ssa->vars[var].phi_use_chain;
      do {
        if (!(ssa->var_info[p->ssa_var].type & MAY_BE_REF)) {
          zend_bitset_incl(worklist, p->ssa_var);
        }
        p = zend_ssa_next_use_phi(ssa, var, p);
      } while (p);
    }

    if (ssa->vars[var].use_chain >= 0) {
      int use = ssa->vars[var].use_chain;
      FOREACH_USE(&ssa->vars[var], use) {
        zend_ssa_op *op = ssa->ops + use;
        if (op->op1_use == var && op->op1_def >= 0) {
          if (!(ssa->var_info[op->op1_def].type & MAY_BE_REF)) {
            /* Unset breaks references (outside global scope). */
            if (op_array->opcodes[use].opcode == ZEND_UNSET_CV
                && op_array->function_name) {
              continue;
            }
            zend_bitset_incl(worklist, op->op1_def);
          }
        }
        if (op->op2_use == var && op->op2_def >= 0) {
          if (!(ssa->var_info[op->op2_def].type & MAY_BE_REF)) {
            zend_bitset_incl(worklist, op->op2_def);
          }
        }
        if (op->result_use == var && op->result_def >= 0) {
          if (!(ssa->var_info[op->result_def].type & MAY_BE_REF)) {
            zend_bitset_incl(worklist, op->result_def);
          }
        }
      } FOREACH_USE_END();
    }
  } WHILE_WORKLIST_END();

  free_alloca(worklist,  use_heap);
}

ZEND_API zend_result zend_ssa_inference(zend_arena **arena, const zend_op_array *op_array, const zend_script *script, zend_ssa *ssa, zend_long optimization_level) /* {{{ */
{
  zend_ssa_var_info *ssa_var_info;
  int i;

  if (!ssa->var_info) {
    ssa->var_info = zend_arena_calloc(arena, ssa->vars_count, sizeof(zend_ssa_var_info));
  }
  ssa_var_info = ssa->var_info;

  if (!op_array->function_name) {
    for (i = 0; i < op_array->last_var; i++) {
      ssa_var_info[i].type = MAY_BE_UNDEF | MAY_BE_RC1 | MAY_BE_RCN | MAY_BE_REF | MAY_BE_ANY  | MAY_BE_ARRAY_KEY_ANY | MAY_BE_ARRAY_OF_ANY | MAY_BE_ARRAY_OF_REF;
      ssa_var_info[i].has_range = 0;
    }
  } else {
    for (i = 0; i < op_array->last_var; i++) {
      ssa_var_info[i].type = MAY_BE_UNDEF;
      ssa_var_info[i].has_range = 0;
      if (ssa->vars[i].alias) {
        ssa_var_info[i].type |= get_ssa_alias_types(ssa->vars[i].alias);
      }
    }
  }
  for (i = op_array->last_var; i < ssa->vars_count; i++) {
    ssa_var_info[i].type = 0;
    ssa_var_info[i].has_range = 0;
  }

  zend_mark_cv_references(op_array, script, ssa);

  zend_infer_ranges(op_array, ssa);

  if (zend_infer_types(op_array, script, ssa, optimization_level) == FAILURE) {
    return FAILURE;
  }

  return SUCCESS;
}
/* }}} */

ZEND_API bool zend_may_throw_ex(const zend_op *opline, const zend_ssa_op *ssa_op, const zend_op_array *op_array, const zend_ssa *ssa, uint32_t t1, uint32_t t2)
{
  if (opline->op1_type == IS_CV) {
    if (t1 & MAY_BE_UNDEF) {
      switch (opline->opcode) {
        case ZEND_UNSET_VAR:
        case ZEND_ISSET_ISEMPTY_VAR:
          return 1;
        case ZEND_ISSET_ISEMPTY_DIM_OBJ:
        case ZEND_ISSET_ISEMPTY_PROP_OBJ:
        case ZEND_ASSIGN:
        case ZEND_ASSIGN_DIM:
        case ZEND_ASSIGN_REF:
        case ZEND_BIND_GLOBAL:
        case ZEND_BIND_STATIC:
        case ZEND_BIND_INIT_STATIC_OR_JMP:
        case ZEND_FETCH_DIM_IS:
        case ZEND_FETCH_OBJ_IS:
        case ZEND_SEND_REF:
        case ZEND_UNSET_CV:
        case ZEND_ISSET_ISEMPTY_CV:
        case ZEND_MAKE_REF:
        case ZEND_FETCH_DIM_W:
          break;
        default:
          /* undefined variable warning */
          return 1;
      }
    }
  } else if (opline->op1_type & (IS_TMP_VAR|IS_VAR)) {
    if ((t1 & MAY_BE_RC1)
     && (t1 & (MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE|MAY_BE_ARRAY_OF_ARRAY))) {
      switch (opline->opcode) {
        case ZEND_CASE:
        case ZEND_CASE_STRICT:
        case ZEND_FE_FETCH_R:
        case ZEND_FE_FETCH_RW:
        case ZEND_FETCH_LIST_R:
        case ZEND_QM_ASSIGN:
        case ZEND_SEND_VAL:
        case ZEND_SEND_VAL_EX:
        case ZEND_SEND_VAR:
        case ZEND_SEND_VAR_EX:
        case ZEND_SEND_FUNC_ARG:
        case ZEND_SEND_VAR_NO_REF:
        case ZEND_SEND_VAR_NO_REF_EX:
        case ZEND_SEND_REF:
        case ZEND_SEPARATE:
        case ZEND_END_SILENCE:
        case ZEND_MAKE_REF:
          break;
        default:
          /* destructor may be called */
          return 1;
      }
    }
  }

  if (opline->op2_type == IS_CV) {
    if (t2 & MAY_BE_UNDEF) {
      switch (opline->opcode) {
        case ZEND_ASSIGN_REF:
        case ZEND_FE_FETCH_R:
        case ZEND_FE_FETCH_RW:
          break;
        default:
          /* undefined variable warning */
          return 1;
      }
    }
  } else if (opline->op2_type & (IS_TMP_VAR|IS_VAR)) {
    if ((t2 & MAY_BE_RC1)
     && (t2 & (MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE|MAY_BE_ARRAY_OF_ARRAY))) {
      switch (opline->opcode) {
        case ZEND_ASSIGN:
        case ZEND_FE_FETCH_R:
        case ZEND_FE_FETCH_RW:
          break;
        default:
          /* destructor may be called */
          return 1;
      }
    }
  }

  switch (opline->opcode) {
    case ZEND_NOP:
    case ZEND_QM_ASSIGN:
    case ZEND_JMP:
    case ZEND_CHECK_VAR:
    case ZEND_MAKE_REF:
    case ZEND_BEGIN_SILENCE:
    case ZEND_END_SILENCE:
    case ZEND_FREE:
    case ZEND_FE_FREE:
    case ZEND_SEPARATE:
    case ZEND_TYPE_CHECK:
    case ZEND_DEFINED:
    case ZEND_ISSET_ISEMPTY_THIS:
    case ZEND_COALESCE:
    case ZEND_SWITCH_LONG:
    case ZEND_SWITCH_STRING:
    case ZEND_MATCH:
    case ZEND_ISSET_ISEMPTY_VAR:
    case ZEND_ISSET_ISEMPTY_CV:
    case ZEND_FUNC_NUM_ARGS:
    case ZEND_FUNC_GET_ARGS:
    case ZEND_COPY_TMP:
    case ZEND_JMP_NULL:
    case ZEND_JMP_FRAMELESS:
      return 0;
    case ZEND_IS_IDENTICAL:
    case ZEND_IS_NOT_IDENTICAL:
    case ZEND_CASE_STRICT:
      /* Array to array comparison may lead to recursion. */
      return (t1 & t2) & MAY_BE_ARRAY_OF_ARRAY;
    case ZEND_SEND_VAR:
    case ZEND_SEND_VAL:
    case ZEND_SEND_REF:
    case ZEND_SEND_VAR_EX:
    case ZEND_SEND_FUNC_ARG:
    case ZEND_CHECK_FUNC_ARG:
      /* May throw for named params. */
      return opline->op2_type == IS_CONST;
    case ZEND_INIT_FCALL:
      /* can't throw, because call is resolved at compile time */
      return 0;
    case ZEND_BIND_GLOBAL:
      if ((opline+1)->opcode == ZEND_BIND_GLOBAL) {
        return zend_may_throw(opline + 1, ssa_op ? ssa_op + 1 : NULL, op_array, ssa);
      }
      return 0;
    case ZEND_ADD:
      if ((t1 & MAY_BE_ANY) == MAY_BE_ARRAY
       && (t2 & MAY_BE_ANY) == MAY_BE_ARRAY) {
        return 0;
      }
      return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
        (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_DIV:
      if (!OP2_HAS_RANGE() ||
        (OP2_MIN_RANGE() <= 0 && OP2_MAX_RANGE() >= 0)) {
        /* Division by zero */
        return 1;
      }
      ZEND_FALLTHROUGH;
    case ZEND_SUB:
    case ZEND_MUL:
    case ZEND_POW:
      return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
        (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    /* Ops may throw if not an integer */
    case ZEND_MOD:
      if (!OP2_HAS_RANGE() ||
        (OP2_MIN_RANGE() <= 0 && OP2_MAX_RANGE() >= 0)) {
        /* Division by zero */
        return 1;
      }
      ZEND_FALLTHROUGH;
    case ZEND_SL:
    case ZEND_SR:
      return (t1 & (MAY_BE_STRING|MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
        (t2 & (MAY_BE_STRING|MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
        !OP2_HAS_RANGE() ||
        OP2_MIN_RANGE() < 0;
    case ZEND_CONCAT:
    case ZEND_FAST_CONCAT:
      return (t1 & (MAY_BE_ARRAY|MAY_BE_OBJECT)) ||
        (t2 & (MAY_BE_ARRAY|MAY_BE_OBJECT));
    case ZEND_BW_OR:
    case ZEND_BW_AND:
    case ZEND_BW_XOR:
      if ((t1 & MAY_BE_ANY) == MAY_BE_STRING
       && (t2 & MAY_BE_ANY) == MAY_BE_STRING) {
        return 0;
      }
      return (t1 & (MAY_BE_STRING|MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
        (t2 & (MAY_BE_STRING|MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_BW_NOT:
      return (t1 & (MAY_BE_NULL|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_PRE_INC:
    case ZEND_POST_INC:
      return (t1 & (MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    /* null emits a warning as it has no effect compared to ++ which converts the value to 1 */
    case ZEND_PRE_DEC:
    case ZEND_POST_DEC:
      return (t1 & (MAY_BE_NULL|MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_JMPZ:
    case ZEND_JMPNZ:
    case ZEND_JMPZ_EX:
    case ZEND_JMPNZ_EX:
    case ZEND_JMP_SET:
      return (t1 & MAY_BE_OBJECT);
    case ZEND_BOOL:
    case ZEND_BOOL_NOT:
      /* NAN Cast to bool will warn, but if we have a range it is fine */
      return (t1 & MAY_BE_OBJECT) || ((t1 & MAY_BE_DOUBLE) && !OP1_HAS_RANGE());
    case ZEND_BOOL_XOR:
      return (t1 & MAY_BE_OBJECT) || (t2 & MAY_BE_OBJECT);
    case ZEND_IS_EQUAL:
    case ZEND_IS_NOT_EQUAL:
    case ZEND_IS_SMALLER:
    case ZEND_IS_SMALLER_OR_EQUAL:
    case ZEND_CASE:
    case ZEND_SPACESHIP:
      if ((t1 & MAY_BE_ANY) == MAY_BE_NULL
       || (t2 & MAY_BE_ANY) == MAY_BE_NULL) {
        return 0;
      }
      return (t1 & (MAY_BE_OBJECT|MAY_BE_ARRAY_OF_ARRAY|MAY_BE_ARRAY_OF_OBJECT)) || (t2 & (MAY_BE_OBJECT|MAY_BE_ARRAY_OF_ARRAY|MAY_BE_ARRAY_OF_OBJECT));
    case ZEND_ASSIGN_OP:
      if (opline->extended_value == ZEND_ADD) {
        if ((t1 & MAY_BE_ANY) == MAY_BE_ARRAY
         && (t2 & MAY_BE_ANY) == MAY_BE_ARRAY) {
          return 0;
        }
        return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
          (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
      } else if (opline->extended_value == ZEND_DIV ||
        opline->extended_value == ZEND_MOD) {
        if (!OP2_HAS_RANGE() ||
          (OP2_MIN_RANGE() <= 0 && OP2_MAX_RANGE() >= 0)) {
          /* Division by zero */
          return 1;
        }
        return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
          (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
      } else if (opline->extended_value == ZEND_SUB ||
        opline->extended_value == ZEND_MUL ||
        opline->extended_value == ZEND_POW) {
        return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
          (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
      } else if (opline->extended_value == ZEND_SL ||
        opline->extended_value == ZEND_SR) {
        return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
          (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
          !OP2_HAS_RANGE() ||
          OP2_MIN_RANGE() < 0;
      } else if (opline->extended_value == ZEND_CONCAT) {
        return (t1 & (MAY_BE_ARRAY|MAY_BE_OBJECT)) ||
          (t2 & (MAY_BE_ARRAY|MAY_BE_OBJECT));
      } else if (opline->extended_value == ZEND_BW_OR ||
        opline->extended_value == ZEND_BW_AND ||
        opline->extended_value == ZEND_BW_XOR) {
        if ((t1 & MAY_BE_ANY) == MAY_BE_STRING
         && (t2 & MAY_BE_ANY) == MAY_BE_STRING) {
          return 0;
        }
        return (t1 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE)) ||
          (t2 & (MAY_BE_STRING|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
      }
      return 1;
    case ZEND_ASSIGN:
      if (t1 & MAY_BE_REF) {
        return 1;
      }
      ZEND_FALLTHROUGH;
    case ZEND_UNSET_VAR:
      return (t1 & (MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE|MAY_BE_ARRAY_OF_ARRAY));
    case ZEND_BIND_STATIC:
    case ZEND_BIND_INIT_STATIC_OR_JMP:
      if (t1 & (MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE|MAY_BE_ARRAY_OF_ARRAY)) {
        /* Destructor may throw. */
        return 1;
      }
      return 0;
    case ZEND_ASSIGN_DIM:
      if ((opline+1)->op1_type == IS_CV) {
        if (OP1_DATA_INFO() & MAY_BE_UNDEF) {
          return 1;
        }
      }
      if (t1 & (MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE|MAY_BE_ARRAY_OF_ARRAY|MAY_BE_ARRAY_OF_REF)) {
        return 1;
      }
      return (t1 & (MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_TRUE|MAY_BE_FALSE|MAY_BE_STRING|MAY_BE_LONG|MAY_BE_DOUBLE)) || opline->op2_type == IS_UNUSED ||
        (t2 & (MAY_BE_UNDEF|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_ASSIGN_OBJ:
      if (t1 & (MAY_BE_ANY-MAY_BE_OBJECT)) {
        return 1;
      }
      if ((opline+1)->op1_type == IS_CV) {
        if (OP1_DATA_INFO() & MAY_BE_UNDEF) {
          return 1;
        }
      }
      if (ssa_op->op1_use) {
        const zend_ssa_var_info *var_info = ssa->var_info + ssa_op->op1_use;
        const zend_class_entry *ce = var_info->ce;

        if (var_info->is_instanceof
         || !ce
         || ce->create_object
         || ce->default_object_handlers->write_property != zend_std_write_property
         || ce->default_object_handlers->get_property_ptr_ptr != zend_std_get_property_ptr_ptr
         || ce->__get
         || ce->__set
         || ce->parent) {
          return 1;
        }

        if (opline->op2_type != IS_CONST) {
          return 1;
        }

        zend_string *prop_name = Z_STR_P(CRT_CONSTANT(opline->op2));
        if (ZSTR_LEN(prop_name) > 0 && ZSTR_VAL(prop_name)[0] == '\0') {
          return 1;
        }

        zend_property_info *prop_info =
          zend_hash_find_ptr(&ce->properties_info, prop_name);
        if (prop_info) {
          if (ZEND_TYPE_IS_SET(prop_info->type)) {
            return 1;
          }
          return !(prop_info->flags & ZEND_ACC_PUBLIC)
            && prop_info->ce != op_array->scope;
        } else {
          return !(ce->ce_flags & ZEND_ACC_ALLOW_DYNAMIC_PROPERTIES);
        }
      }
      return 1;
    case ZEND_ROPE_INIT:
    case ZEND_ROPE_ADD:
    case ZEND_ROPE_END:
      return t2 & (MAY_BE_ARRAY|MAY_BE_OBJECT);
    case ZEND_INIT_ARRAY:
      return (opline->op2_type != IS_UNUSED) && (t2 & (MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_ADD_ARRAY_ELEMENT:
      return (opline->op2_type == IS_UNUSED) || (t2 & (MAY_BE_NULL|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_STRLEN:
      return (t1 & MAY_BE_ANY) != MAY_BE_STRING;
    case ZEND_COUNT:
      return (t1 & MAY_BE_ANY) != MAY_BE_ARRAY;
    case ZEND_RECV_INIT:
      if (Z_TYPE_P(CRT_CONSTANT(opline->op2)) == IS_CONSTANT_AST) {
        return 1;
      }
      if (op_array->fn_flags & ZEND_ACC_HAS_TYPE_HINTS) {
        uint32_t arg_num = opline->op1.num;
        const zend_arg_info *cur_arg_info;

        if (EXPECTED(arg_num <= op_array->num_args)) {
          cur_arg_info = &op_array->arg_info[arg_num-1];
        } else if (UNEXPECTED(op_array->fn_flags & ZEND_ACC_VARIADIC)) {
          cur_arg_info = &op_array->arg_info[op_array->num_args];
        } else {
          return 0;
        }
        return ZEND_TYPE_IS_SET(cur_arg_info->type);
      } else {
        return 0;
      }
    case ZEND_FETCH_IS:
      return (t2 & (MAY_BE_ARRAY|MAY_BE_OBJECT));
    case ZEND_ISSET_ISEMPTY_DIM_OBJ:
      return (t1 & MAY_BE_OBJECT) || (t2 & (MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT));
    case ZEND_FETCH_DIM_IS:
      return (t1 & MAY_BE_OBJECT) || (t2 & (MAY_BE_DOUBLE|MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE));
    case ZEND_CAST:
      switch (opline->extended_value) {
        case IS_LONG:
          return (t1 & (MAY_BE_DOUBLE|MAY_BE_STRING|MAY_BE_OBJECT));
        case IS_DOUBLE:
          return (t1 & MAY_BE_OBJECT);
        case IS_STRING:
          return (t1 & (MAY_BE_ARRAY|MAY_BE_OBJECT));
        case IS_ARRAY:
          return (t1 & MAY_BE_OBJECT);
        case IS_OBJECT:
          return 0;
        default: ZEND_UNREACHABLE();
      }
      /* GCC is getting confused here for the Wimplicit-fallthrough warning with
       * default: ZEND_UNREACHABLE(); macro */
      return 0;
    case ZEND_ARRAY_KEY_EXISTS:
      if ((t2 & MAY_BE_ANY) != MAY_BE_ARRAY) {
        return 1;
      }
      if ((t1 & (MAY_BE_ARRAY|MAY_BE_OBJECT|MAY_BE_RESOURCE))) {
        return 1;
      }
      return 0;
    case ZEND_FE_RESET_R:
    case ZEND_FE_RESET_RW:
      if ((t1 & (MAY_BE_ANY|MAY_BE_REF)) != MAY_BE_ARRAY) {
        return 1;
      }
      return 0;
    case ZEND_FE_FETCH_R:
      if ((t1 & (MAY_BE_ANY|MAY_BE_REF)) != MAY_BE_ARRAY) {
        return 1;
      }
      if (opline->op2_type == IS_CV
       && (t2 & MAY_BE_RC1)
       && (t2 & (MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_ARRAY_OF_OBJECT|MAY_BE_ARRAY_OF_RESOURCE|MAY_BE_ARRAY_OF_ARRAY))) {
        return 1;
      }
      return 0;
    case ZEND_FETCH_DIM_W:
    case ZEND_FETCH_LIST_W:
      if (t1 & (MAY_BE_FALSE|MAY_BE_TRUE|MAY_BE_LONG|MAY_BE_DOUBLE|MAY_BE_STRING|MAY_BE_OBJECT|MAY_BE_RESOURCE|MAY_BE_REF)) {
        return 1;
      }
      if (t2 & (MAY_BE_RESOURCE|MAY_BE_ARRAY|MAY_BE_OBJECT)) {
        return 1;
      }
      if (opline->op2_type == IS_UNUSED) {
        return 1;
      }
      return 0;
    case ZEND_YIELD_FROM: {
      uint32_t t1 = OP1_INFO();
      if ((t1 & (MAY_BE_ANY|MAY_BE_UNDEF)) == MAY_BE_ARRAY && MAY_BE_EMPTY_ONLY(t1)) {
        return false;
      }
      return true;
    }
    default:
      return 1;
  }
}

ZEND_API bool zend_may_throw(const zend_op *opline, const zend_ssa_op *ssa_op, const zend_op_array *op_array, const zend_ssa *ssa)
{
  return zend_may_throw_ex(opline, ssa_op, op_array, ssa, OP1_INFO(), OP2_INFO());
}

Coverage Report

Created: 2026-06-02 06:40