Remove dead code for ADD_STRING/ADD_CHAR optimization

These opcodes don't exist anymore. The modern equivalent would be
the ROPE_* opcodes. However the code would have to be different
anyway.

Author: nikic

ext/opcache/Optimizer/pass1_5.c

@@ -22,7 +22,6 @@
 /* pass 1
  * - substitute persistent constants (true, false, null, etc)
  * - perform compile-time evaluation of constant binary and unary operations
- * - optimize series of ADD_STRING and/or ADD_CHAR
  * - convert CAST(IS_BOOL,x) into BOOL(x)
  * - pre-evaluate constant function calls
  */
@@ -129,79 +128,6 @@ void zend_optimizer_pass1(zend_op_array *op_array, zend_optimizer_ctx *ctx)
 			}
 			break;
 
-#if 0
-		case ZEND_ADD_STRING:
-		case ZEND_ADD_CHAR:
-			{
-				zend_op *next_op = opline + 1;
-				int requires_conversion = (opline->opcode == ZEND_ADD_CHAR? 1 : 0);
-				size_t final_length = 0;
-				zend_string *str;
-				char *ptr;
-				zend_op *last_op;
-
-				/* There is always a ZEND_RETURN at the end
-				if (next_op>=end) {
-					break;
-				}
-				*/
-				while (next_op->opcode == ZEND_ADD_STRING || next_op->opcode == ZEND_ADD_CHAR) {
-					if (opline->result.var != next_op->result.var) {
-						break;
-					}
-					if (next_op->opcode == ZEND_ADD_CHAR) {
-						final_length += 1;
-					} else { /* ZEND_ADD_STRING */
-						final_length += Z_STRLEN(ZEND_OP2_LITERAL(next_op));
-					}
-					next_op++;
-				}
-				if (final_length == 0) {
-					break;
-				}
-				last_op = next_op;
-				final_length += (requires_conversion? 1 : Z_STRLEN(ZEND_OP2_LITERAL(opline)));
-				str = zend_string_alloc(final_length, 0);
-				str->len = final_length;
-				ptr = str->val;
-				ptr[final_length] = '\0';
-				if (requires_conversion) { /* ZEND_ADD_CHAR */
-					char chval = (char)Z_LVAL(ZEND_OP2_LITERAL(opline));
-
-					ZVAL_NEW_STR(&ZEND_OP2_LITERAL(opline), str);
-					ptr[0] = chval;
-					opline->opcode = ZEND_ADD_STRING;
-					ptr++;
-				} else { /* ZEND_ADD_STRING */
-					memcpy(ptr, Z_STRVAL(ZEND_OP2_LITERAL(opline)), Z_STRLEN(ZEND_OP2_LITERAL(opline)));
-					ptr += Z_STRLEN(ZEND_OP2_LITERAL(opline));
-					zend_string_release_ex(Z_STR(ZEND_OP2_LITERAL(opline)), 0);
-					ZVAL_NEW_STR(&ZEND_OP2_LITERAL(opline), str);
-				}
-				next_op = opline + 1;
-				while (next_op < last_op) {
-					if (next_op->opcode == ZEND_ADD_STRING) {
-						memcpy(ptr, Z_STRVAL(ZEND_OP2_LITERAL(next_op)), Z_STRLEN(ZEND_OP2_LITERAL(next_op)));
-						ptr += Z_STRLEN(ZEND_OP2_LITERAL(next_op));
-						literal_dtor(&ZEND_OP2_LITERAL(next_op));
-					} else { /* ZEND_ADD_CHAR */
-						*ptr = (char)Z_LVAL(ZEND_OP2_LITERAL(next_op));
-						ptr++;
-					}
-					MAKE_NOP(next_op);
-					next_op++;
-				}
-				if (!((ZEND_OPTIMIZER_PASS_5|ZEND_OPTIMIZER_PASS_10) & OPTIMIZATION_LEVEL)) {
-					/* NOP removal is disabled => insert JMP over NOPs */
-					if (last_op-opline >= 3) { /* If we have more than 2 NOPS then JMP over them */
-						(opline + 1)->opcode = ZEND_JMP;
-						(opline + 1)->op1.opline_num = last_op - op_array->opcodes; /* that's OK even for ZE2, since opline_num's are resolved in pass 2 later */
-					}
-				}
-			}
-			break;
-#endif
-
 		case ZEND_FETCH_CONSTANT:
 			if (opline->op2_type == IS_CONST &&
 				Z_TYPE(ZEND_OP2_LITERAL(opline)) == IS_STRING &&