diff options
Diffstat (limited to 'Zend/Optimizer/nop_removal.c')
| -rw-r--r-- | Zend/Optimizer/nop_removal.c | 106 |
1 files changed, 106 insertions, 0 deletions
diff --git a/Zend/Optimizer/nop_removal.c b/Zend/Optimizer/nop_removal.c new file mode 100644 index 0000000000..32d2f10bf4 --- /dev/null +++ b/Zend/Optimizer/nop_removal.c @@ -0,0 +1,106 @@ +/* + +----------------------------------------------------------------------+ + | Zend OPcache | + +----------------------------------------------------------------------+ + | Copyright (c) The PHP Group | + +----------------------------------------------------------------------+ + | This source file is subject to version 3.01 of the PHP license, | + | that is bundled with this package in the file LICENSE, and is | + | available through the world-wide-web at the following url: | + | http://www.php.net/license/3_01.txt | + | If you did not receive a copy of the PHP license and are unable to | + | obtain it through the world-wide-web, please send a note to | + | license@php.net so we can mail you a copy immediately. | + +----------------------------------------------------------------------+ + | Authors: Andi Gutmans <andi@php.net> | + | Zeev Suraski <zeev@php.net> | + | Stanislav Malyshev <stas@zend.com> | + | Dmitry Stogov <dmitry@php.net> | + +----------------------------------------------------------------------+ +*/ + +/* pass 10: + * - remove NOPs + */ + +#include "php.h" +#include "Optimizer/zend_optimizer.h" +#include "Optimizer/zend_optimizer_internal.h" +#include "zend_API.h" +#include "zend_constants.h" +#include "zend_execute.h" +#include "zend_vm.h" + +void zend_optimizer_nop_removal(zend_op_array *op_array, zend_optimizer_ctx *ctx) +{ + zend_op *end, *opline; + uint32_t new_count, i, shift; + int j; + uint32_t *shiftlist; + ALLOCA_FLAG(use_heap); + + shiftlist = (uint32_t *)do_alloca(sizeof(uint32_t) * op_array->last, use_heap); + i = new_count = shift = 0; + end = op_array->opcodes + op_array->last; + for (opline = op_array->opcodes; opline < end; opline++) { + + /* Kill JMP-over-NOP-s */ + if (opline->opcode == ZEND_JMP && ZEND_OP1_JMP_ADDR(opline) > op_array->opcodes + i) { + /* check if there are only NOPs under the branch */ + zend_op *target = ZEND_OP1_JMP_ADDR(opline) - 1; + + while (target->opcode == ZEND_NOP) { + target--; + } + if (target == opline) { + /* only NOPs */ + opline->opcode = ZEND_NOP; + } + } + + shiftlist[i++] = shift; + if (opline->opcode == ZEND_NOP) { + shift++; + } else { + if (shift) { + zend_op *new_opline = op_array->opcodes + new_count; + + *new_opline = *opline; + zend_optimizer_migrate_jump(op_array, new_opline, opline); + } + new_count++; + } + } + + if (shift) { + op_array->last = new_count; + end = op_array->opcodes + op_array->last; + + /* update JMPs */ + for (opline = op_array->opcodes; opline<end; opline++) { + zend_optimizer_shift_jump(op_array, opline, shiftlist); + } + + /* update try/catch array */ + for (j = 0; j < op_array->last_try_catch; j++) { + op_array->try_catch_array[j].try_op -= shiftlist[op_array->try_catch_array[j].try_op]; + op_array->try_catch_array[j].catch_op -= shiftlist[op_array->try_catch_array[j].catch_op]; + if (op_array->try_catch_array[j].finally_op) { + op_array->try_catch_array[j].finally_op -= shiftlist[op_array->try_catch_array[j].finally_op]; + op_array->try_catch_array[j].finally_end -= shiftlist[op_array->try_catch_array[j].finally_end]; + } + } + + /* update early binding list */ + if (op_array->fn_flags & ZEND_ACC_EARLY_BINDING) { + uint32_t *opline_num = &ctx->script->first_early_binding_opline; + + ZEND_ASSERT(op_array == &ctx->script->main_op_array); + do { + *opline_num -= shiftlist[*opline_num]; + opline_num = &op_array->opcodes[*opline_num].result.opline_num; + } while (*opline_num != (uint32_t)-1); + } + } + free_alloca(shiftlist, use_heap); +} |