Coverage Report

Created: 2026-06-02 06:39

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/php-src/Zend/Optimizer/nop_removal.c
Line
Count
Source
1
/*
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   +----------------------------------------------------------------------+
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   | Zend OPcache                                                         |
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   +----------------------------------------------------------------------+
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   | Copyright © The PHP Group and Contributors.                          |
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   +----------------------------------------------------------------------+
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   | This source file is subject to the Modified BSD License that is      |
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   | bundled with this package in the file LICENSE, and is available      |
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   | through the World Wide Web at <https://www.php.net/license/>.        |
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   |                                                                      |
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   | SPDX-License-Identifier: BSD-3-Clause                                |
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   +----------------------------------------------------------------------+
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   | Authors: Andi Gutmans <andi@php.net>                                 |
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   |          Zeev Suraski <zeev@php.net>                                 |
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   |          Stanislav Malyshev <stas@zend.com>                          |
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   |          Dmitry Stogov <dmitry@php.net>                              |
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   +----------------------------------------------------------------------+
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*/
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/* pass 10:
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 * - remove NOPs
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 */
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#include "Optimizer/zend_optimizer.h"
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#include "Optimizer/zend_optimizer_internal.h"
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#include "zend_API.h"
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#include "zend_constants.h"
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#include "zend_execute.h"
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#include "zend_vm.h"
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void zend_optimizer_nop_removal(zend_op_array *op_array, zend_optimizer_ctx *ctx)
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0
{
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0
  zend_op *opline;
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0
  uint32_t new_count, i, shift;
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0
  uint32_t *shiftlist;
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0
  ALLOCA_FLAG(use_heap);
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0
  shiftlist = (uint32_t *)do_alloca(sizeof(uint32_t) * op_array->last, use_heap);
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0
  i = new_count = shift = 0;
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0
  const zend_op *end = op_array->opcodes + op_array->last;
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0
  for (opline = op_array->opcodes; opline < end; opline++) {
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    /* Kill JMP-over-NOP-s */
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0
    if (opline->opcode == ZEND_JMP && ZEND_OP1_JMP_ADDR(opline) > op_array->opcodes + i) {
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      /* check if there are only NOPs under the branch */
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0
      const zend_op *target = ZEND_OP1_JMP_ADDR(opline) - 1;
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0
      while (target->opcode == ZEND_NOP) {
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0
        target--;
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0
      }
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0
      if (target == opline) {
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        /* only NOPs */
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0
        opline->opcode = ZEND_NOP;
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0
      }
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0
    }
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0
    shiftlist[i++] = shift;
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0
    if (opline->opcode == ZEND_NOP) {
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0
      shift++;
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0
    } else {
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0
      if (shift) {
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0
        zend_op *new_opline = op_array->opcodes + new_count;
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0
        *new_opline = *opline;
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0
        zend_optimizer_migrate_jump(op_array, new_opline, opline);
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0
      }
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0
      new_count++;
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0
    }
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0
  }
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0
  if (shift) {
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0
    op_array->last = new_count;
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0
    end = op_array->opcodes + op_array->last;
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    /* update JMPs */
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0
    for (opline = op_array->opcodes; opline<end; opline++) {
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0
      zend_optimizer_shift_jump(op_array, opline, shiftlist);
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0
    }
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    /* update try/catch array */
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0
    for (uint32_t j = 0; j < op_array->last_try_catch; j++) {
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0
      op_array->try_catch_array[j].try_op -= shiftlist[op_array->try_catch_array[j].try_op];
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0
      op_array->try_catch_array[j].catch_op -= shiftlist[op_array->try_catch_array[j].catch_op];
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0
      if (op_array->try_catch_array[j].finally_op) {
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0
        op_array->try_catch_array[j].finally_op -= shiftlist[op_array->try_catch_array[j].finally_op];
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0
        op_array->try_catch_array[j].finally_end -= shiftlist[op_array->try_catch_array[j].finally_end];
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0
      }
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0
    }
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0
  }
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  free_alloca(shiftlist, use_heap);
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0
}