Optimize return type checking

Split off the fast-path case and avoid redundant checks.

Author: nikic

Zend/zend_execute.c

@@ -1027,24 +1027,11 @@ static zend_never_inline zval* zend_assign_to_typed_prop(zend_property_info *inf
 	return zend_assign_to_variable(property_val, &tmp, IS_TMP_VAR, EX_USES_STRICT_TYPES());
 }
 
-
-static zend_always_inline zend_bool zend_check_type(
-		zend_type type, zval *arg, void **cache_slot, zend_class_entry *scope,
+static zend_always_inline zend_bool zend_check_type_slow(
+		zend_type type, zval *arg, zend_reference *ref, void **cache_slot, zend_class_entry *scope,
 		zend_bool is_return_type, zend_bool is_internal)
 {
-	zend_reference *ref = NULL;
 	uint32_t type_mask;
-	ZEND_ASSERT(ZEND_TYPE_IS_SET(type));
-
-	if (UNEXPECTED(Z_ISREF_P(arg))) {
-		ref = Z_REF_P(arg);
-		arg = Z_REFVAL_P(arg);
-	}
-
-	if (EXPECTED(ZEND_TYPE_CONTAINS_CODE(type, Z_TYPE_P(arg)))) {
-		return 1;
-	}
-
 	if (ZEND_TYPE_HAS_CLASS(type) && Z_TYPE_P(arg) == IS_OBJECT) {
 		zend_class_entry *ce;
 		if (ZEND_TYPE_HAS_LIST(type)) {
@@ -1109,6 +1096,25 @@ static zend_always_inline zend_bool zend_check_type(
 	 * because this case is already checked at compile-time. */
 }
 
+static zend_always_inline zend_bool zend_check_type(
+		zend_type type, zval *arg, void **cache_slot, zend_class_entry *scope,
+		zend_bool is_return_type, zend_bool is_internal)
+{
+	zend_reference *ref = NULL;
+	ZEND_ASSERT(ZEND_TYPE_IS_SET(type));
+
+	if (UNEXPECTED(Z_ISREF_P(arg))) {
+		ref = Z_REF_P(arg);
+		arg = Z_REFVAL_P(arg);
+	}
+
+	if (EXPECTED(ZEND_TYPE_CONTAINS_CODE(type, Z_TYPE_P(arg)))) {
+		return 1;
+	}
+
+	return zend_check_type_slow(type, arg, ref, cache_slot, scope, is_return_type, is_internal);
+}
+
 static zend_always_inline int zend_verify_recv_arg_type(zend_function *zf, uint32_t arg_num, zval *arg, void **cache_slot)
 {
 	zend_arg_info *cur_arg_info;

Zend/zend_vm_def.h

@@ -4098,15 +4098,15 @@ ZEND_VM_COLD_CONST_HANDLER(124, ZEND_VERIFY_RETURN_TYPE, CONST|TMP|VAR|UNUSED|CV
 {
 	USE_OPLINE
 
-	SAVE_OPLINE();
 	if (OP1_TYPE == IS_UNUSED) {
+		SAVE_OPLINE();
 		zend_verify_missing_return_type(EX(func), CACHE_ADDR(opline->op2.num));
+		HANDLE_EXCEPTION();
 	} else {
 /* prevents "undefined variable opline" errors */
 #if !ZEND_VM_SPEC || (OP1_TYPE != IS_UNUSED)
 		zval *retval_ref, *retval_ptr;
 		zend_arg_info *ret_info = EX(func)->common.arg_info - 1;
-
 		retval_ref = retval_ptr = GET_OP1_ZVAL_PTR(BP_VAR_R);
 
 		if (OP1_TYPE == IS_CONST) {
@@ -4121,24 +4121,35 @@ ZEND_VM_COLD_CONST_HANDLER(124, ZEND_VERIFY_RETURN_TYPE, CONST|TMP|VAR|UNUSED|CV
 			ZVAL_DEREF(retval_ptr);
 		}
 
-		if (UNEXPECTED((ZEND_TYPE_FULL_MASK(ret_info->type) & MAY_BE_ANY)
-			&& !ZEND_TYPE_CONTAINS_CODE(ret_info->type, Z_TYPE_P(retval_ptr))
-			&& !(EX(func)->op_array.fn_flags & ZEND_ACC_RETURN_REFERENCE)
-			&& retval_ref != retval_ptr)
-		) {
-			/* A cast might happen - unwrap the reference if this is a by-value return */
-			if (Z_REFCOUNT_P(retval_ref) == 1) {
-				ZVAL_UNREF(retval_ref);
+		if (EXPECTED(ZEND_TYPE_CONTAINS_CODE(ret_info->type, Z_TYPE_P(retval_ptr)))) {
+			ZEND_VM_NEXT_OPCODE();
+		}
+
+		zend_reference *ref = NULL;
+		void *cache_slot = CACHE_ADDR(opline->op2.num);
+		if (UNEXPECTED(retval_ref != retval_ptr)) {
+			if (UNEXPECTED(EX(func)->op_array.fn_flags & ZEND_ACC_RETURN_REFERENCE)) {
+				ref = Z_REF_P(retval_ref);
 			} else {
-				Z_DELREF_P(retval_ref);
-				ZVAL_COPY(retval_ref, retval_ptr);
+				/* A cast might happen - unwrap the reference if this is a by-value return */
+				if (Z_REFCOUNT_P(retval_ref) == 1) {
+					ZVAL_UNREF(retval_ref);
+				} else {
+					Z_DELREF_P(retval_ref);
+					ZVAL_COPY(retval_ref, retval_ptr);
+				}
+				retval_ptr = retval_ref;
 			}
-			retval_ptr = retval_ref;
 		}
-		zend_verify_return_type(EX(func), retval_ptr, CACHE_ADDR(opline->op2.num));
+
+		SAVE_OPLINE();
+		if (UNEXPECTED(!zend_check_type_slow(ret_info->type, retval_ptr, ref, cache_slot, NULL, 1, 0))) {
+			zend_verify_return_error(EX(func), cache_slot, retval_ptr);
+			HANDLE_EXCEPTION();
+		}
+		ZEND_VM_NEXT_OPCODE();
 #endif
 	}
-	ZEND_VM_NEXT_OPCODE_CHECK_EXCEPTION();
 }
 
 ZEND_VM_INLINE_HANDLER(62, ZEND_RETURN, CONST|TMP|VAR|CV, ANY)