Fixed issue #183 (TMP_VAR is not only used once)

diff --git a/ext/opcache/Optimizer/zend_optimizer.c b/ext/opcache/Optimizer/zend_optimizer.c
index fd0f77dbc8a018a7d965c08e4207d76be317a761..ae85c7bc8670a9043680c1e3425671d0ae3829bb 100644 (file)
--- a/ext/opcache/Optimizer/zend_optimizer.c
+++ b/ext/opcache/Optimizer/zend_optimizer.c
@@ -284,20 +284,41 @@ static void replace_tmp_by_const(zend_op_array *op_array,
                if (ZEND_OP1_TYPE(opline) == IS_TMP_VAR &&
                        ZEND_OP1(opline).var == var) {
 
-                       update_op1_const(op_array, opline, val TSRMLS_CC);
-                       /* TMP_VAR my be used only once */
-                       break;
+                       /* In most cases IS_TMP_VAR operand may be used only once.
+                        * The operands are usually destroyed by the opcode handler.
+                        * ZEND_CASE is an exception, that keeps operand unchanged,
+                        * and allows its reuse. The number of ZEND_CASE instructions
+                        * usually terminated by ZEND_FREE that finally kills the value.
+                        */
+                       if (opline->opcode == ZEND_CASE) {
+                               zval old_val;
+                               old_val = *val;
+                               zval_copy_ctor(val);
+                               update_op1_const(op_array, opline, val TSRMLS_CC);
+                               *val = old_val;
+                       } else if (opline->opcode == ZEND_FREE) {
+                               MAKE_NOP(opline);
+                               break;
+                       } else {                                
+                               update_op1_const(op_array, opline, val TSRMLS_CC);
+                               val = NULL;
+                               break;
+                       }
                }
 
                if (ZEND_OP2_TYPE(opline) == IS_TMP_VAR &&
                        ZEND_OP2(opline).var == var) {
 
                        update_op2_const(op_array, opline, val TSRMLS_CC);
-                       /* TMP_VAR my be used only once */
+                       /* TMP_VAR may be used only once */
+                       val = NULL;
                        break;
                }
                opline++;
        }
+       if (val) {
+               zval_dtor(val);
+       }
 }
 
 #include "Optimizer/nop_removal.c"