Allow using prototypes when optimizing arg passing

Closes GH-5193.

Author: nikic

ext/opcache/Optimizer/optimize_func_calls.c

@@ -39,6 +39,7 @@
 typedef struct _optimizer_call_info {
 	zend_function *func;
 	zend_op       *opline;
+	zend_bool      is_prototype;
 	zend_bool      try_inline;
 	uint32_t       func_arg_num;
 } optimizer_call_info;
@@ -172,9 +173,12 @@ void zend_optimize_func_calls(zend_op_array *op_array, zend_optimizer_ctx *ctx)
 			case ZEND_INIT_METHOD_CALL:
 			case ZEND_INIT_FCALL:
 			case ZEND_NEW:
+				/* The argument passing optimizations are valid for prototypes as well,
+				 * as inheritance cannot change between ref <-> non-ref arguments. */
 				call_stack[call].func = zend_optimizer_get_called_func(
-					ctx->script, op_array, opline);
-				call_stack[call].try_inline = opline->opcode != ZEND_NEW;
+					ctx->script, op_array, opline, &call_stack[call].is_prototype);
+				call_stack[call].try_inline =
+					!call_stack[call].is_prototype && opline->opcode != ZEND_NEW;
 				/* break missing intentionally */
 			case ZEND_INIT_DYNAMIC_CALL:
 			case ZEND_INIT_USER_CALL:

ext/opcache/Optimizer/zend_call_graph.c

@@ -93,6 +93,7 @@ int zend_analyze_calls(zend_arena **arena, zend_script *script, uint32_t build_f
 	int call = 0;
 	zend_call_info **call_stack;
 	ALLOCA_FLAG(use_heap);
+	zend_bool is_prototype;
 
 	call_stack = do_alloca((op_array->last / 2) * sizeof(zend_call_info*), use_heap);
 	call_info = NULL;
@@ -103,8 +104,9 @@ int zend_analyze_calls(zend_arena **arena, zend_script *script, uint32_t build_f
 			case ZEND_INIT_STATIC_METHOD_CALL:
 				call_stack[call] = call_info;
 				func = zend_optimizer_get_called_func(
-					script, op_array, opline);
-				if (func) {
+					script, op_array, opline, &is_prototype);
+				/* TODO: Support prototypes? */
+				if (func && !is_prototype) {
 					call_info = zend_arena_calloc(arena, 1, sizeof(zend_call_info) + (sizeof(zend_send_arg_info) * ((int)opline->extended_value - 1)));
 					call_info->caller_op_array = op_array;
 					call_info->caller_init_opline = opline;

ext/opcache/Optimizer/zend_optimizer.c

@@ -777,8 +777,9 @@ static zend_class_entry *get_class_entry_from_op1(
 }
 
 zend_function *zend_optimizer_get_called_func(
-		zend_script *script, zend_op_array *op_array, zend_op *opline)
+		zend_script *script, zend_op_array *op_array, zend_op *opline, zend_bool *is_prototype)
 {
+	*is_prototype = 0;
 	switch (opline->opcode) {
 		case ZEND_INIT_FCALL:
 		{
@@ -825,7 +826,7 @@ zend_function *zend_optimizer_get_called_func(
 					if (fbc) {
 						zend_bool is_public = (fbc->common.fn_flags & ZEND_ACC_PUBLIC) != 0;
 						zend_bool same_scope = fbc->common.scope == op_array->scope;
-						if (is_public|| same_scope) {
+						if (is_public || same_scope) {
 							return fbc;
 						}
 					}
@@ -843,10 +844,15 @@ zend_function *zend_optimizer_get_called_func(
 					zend_bool is_private = (fbc->common.fn_flags & ZEND_ACC_PRIVATE) != 0;
 					zend_bool is_final = (fbc->common.fn_flags & ZEND_ACC_FINAL) != 0;
 					zend_bool same_scope = fbc->common.scope == op_array->scope;
-					if ((is_private && same_scope)
-							|| (is_final && (!is_private || same_scope))) {
-						return fbc;
+					if (is_private) {
+						/* Only use private method if in the same scope. We can't even use it
+						 * as a prototype, as it may be overridden with changed signature. */
+						return same_scope ? fbc : NULL;
 					}
+					/* If the method is non-final, it may be overriden,
+					 * but only with a compatible method signature. */
+					*is_prototype = !is_final;
+					return fbc;
 				}
 			}
 			break;

ext/opcache/Optimizer/zend_optimizer_internal.h

@@ -110,7 +110,7 @@ void zend_optimizer_compact_literals(zend_op_array *op_array, zend_optimizer_ctx
 void zend_optimizer_compact_vars(zend_op_array *op_array);
 int zend_optimizer_is_disabled_func(const char *name, size_t len);
 zend_function *zend_optimizer_get_called_func(
-		zend_script *script, zend_op_array *op_array, zend_op *opline);
+		zend_script *script, zend_op_array *op_array, zend_op *opline, zend_bool *is_prototype);
 uint32_t zend_optimizer_classify_function(zend_string *name, uint32_t num_args);
 void zend_optimizer_migrate_jump(zend_op_array *op_array, zend_op *new_opline, zend_op *opline);
 void zend_optimizer_shift_jump(zend_op_array *op_array, zend_op *opline, uint32_t *shiftlist);