diff options
Diffstat (limited to 'ext/opcache/Optimizer/nop_removal.c')
| -rw-r--r-- | ext/opcache/Optimizer/nop_removal.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/ext/opcache/Optimizer/nop_removal.c b/ext/opcache/Optimizer/nop_removal.c new file mode 100644 index 0000000000..b2fb667ed5 --- /dev/null +++ b/ext/opcache/Optimizer/nop_removal.c @@ -0,0 +1,126 @@ +/* pass 10: + * - remove NOPs + */ + +static void nop_removal(zend_op_array *op_array) +{ + zend_op *end, *opline; + zend_uint new_count, i, shift; + int j; + zend_uint *shiftlist; + ALLOCA_FLAG(use_heap); + + shiftlist = (zend_uint *)DO_ALLOCA(sizeof(zend_uint) * op_array->last); + i = new_count = shift = 0; + end = op_array->opcodes + op_array->last; + for (opline = op_array->opcodes; opline < end; opline++) { + +#if ZEND_EXTENSION_API_NO >= PHP_5_3_X_API_NO + /* GOTO target is unresolved yet. We can't optimize. */ + if (opline->opcode == ZEND_GOTO && + Z_TYPE(ZEND_OP2_LITERAL(opline)) != IS_LONG) { + /* TODO: in general we can avoid this restriction */ + FREE_ALLOCA(shiftlist); + return; + } +#endif + + /* Kill JMP-over-NOP-s */ + if (opline->opcode == ZEND_JMP && ZEND_OP1(opline).opline_num > i) { + /* check if there are only NOPs under the branch */ + zend_op *target = op_array->opcodes + ZEND_OP1(opline).opline_num - 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) { + op_array->opcodes[new_count] = *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++) { + switch (opline->opcode) { + case ZEND_JMP: +#if ZEND_EXTENSION_API_NO >= PHP_5_3_X_API_NO + case ZEND_GOTO: +#endif +#if ZEND_EXTENSION_API_NO > PHP_5_4_X_API_NO + case ZEND_FAST_CALL: +#endif + ZEND_OP1(opline).opline_num -= shiftlist[ZEND_OP1(opline).opline_num]; + break; + case ZEND_JMPZ: + case ZEND_JMPNZ: + case ZEND_JMPZ_EX: + case ZEND_JMPNZ_EX: + case ZEND_FE_FETCH: + case ZEND_FE_RESET: + case ZEND_NEW: +#if ZEND_EXTENSION_API_NO >= PHP_5_3_X_API_NO + case ZEND_JMP_SET: +#endif +#if ZEND_EXTENSION_API_NO > PHP_5_3_X_API_NO + case ZEND_JMP_SET_VAR: +#endif + ZEND_OP2(opline).opline_num -= shiftlist[ZEND_OP2(opline).opline_num]; + break; + case ZEND_JMPZNZ: + ZEND_OP2(opline).opline_num -= shiftlist[ZEND_OP2(opline).opline_num]; + opline->extended_value -= shiftlist[opline->extended_value]; + break; + case ZEND_CATCH: + opline->extended_value -= shiftlist[opline->extended_value]; + break; + } + } + + /* update brk/cont array */ + for (j = 0; j < op_array->last_brk_cont; j++) { + op_array->brk_cont_array[j].brk -= shiftlist[op_array->brk_cont_array[j].brk]; + op_array->brk_cont_array[j].cont -= shiftlist[op_array->brk_cont_array[j].cont]; + op_array->brk_cont_array[j].start -= shiftlist[op_array->brk_cont_array[j].start]; + } + + /* 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 ZEND_EXTENSION_API_NO > PHP_5_4_X_API_NO + 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]; + } +#endif + } + +#if ZEND_EXTENSION_API_NO >= PHP_5_3_X_API_NO + /* update early binding list */ + if (op_array->early_binding != (zend_uint)-1) { + zend_uint *opline_num = &op_array->early_binding; + + do { + *opline_num -= shiftlist[*opline_num]; + opline_num = &ZEND_RESULT(&op_array->opcodes[*opline_num]).opline_num; + } while (*opline_num != (zend_uint)-1); + } +#endif + } + FREE_ALLOCA(shiftlist); +} |