[asm.js] [wasm] Store function start position for stack check

src/runtime/runtime-test.cc

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/runtime/runtime-utils.h"
 
 #include <memory>
 
 #include "src/arguments.h"
 #include "src/compiler-dispatcher/optimizing-compile-dispatcher.h"
@@ skipping 681 matching lines @@
     return isolate->heap()->false_value();
   }
   if (function->shared()->code() !=
       isolate->builtins()->builtin(Builtins::kInstantiateAsmJs)) {
     // Hasn't been compiled yet.
     return isolate->heap()->false_value();
   }
   return isolate->heap()->true_value();
 }
 
+RUNTIME_FUNCTION(Runtime_IsWasmCode) {
+  SealHandleScope shs(isolate);
+  DCHECK_EQ(1, args.length());
+  CONVERT_ARG_CHECKED(JSFunction, function, 0);
+  bool is_js_to_wasm = function->code()->kind() == Code::JS_TO_WASM_FUNCTION;
+  return isolate->heap()->ToBoolean(is_js_to_wasm);
+}
 
 #define ELEMENTS_KIND_CHECK_RUNTIME_FUNCTION(Name)       \
   RUNTIME_FUNCTION(Runtime_Has##Name) {                  \
     CONVERT_ARG_CHECKED(JSObject, obj, 0);               \
     return isolate->heap()->ToBoolean(obj->Has##Name()); \
   }
 
 ELEMENTS_KIND_CHECK_RUNTIME_FUNCTION(FastSmiElements)
 ELEMENTS_KIND_CHECK_RUNTIME_FUNCTION(FastObjectElements)
 ELEMENTS_KIND_CHECK_RUNTIME_FUNCTION(FastSmiOrObjectElements)
@@ skipping 104 matching lines @@
 RUNTIME_FUNCTION(Runtime_ValidateWasmOrphanedInstance) {
   HandleScope shs(isolate);
   DCHECK(args.length() == 1);
   CONVERT_ARG_HANDLE_CHECKED_2(WasmInstanceObject, instance, 0);
   wasm::testing::ValidateOrphanedInstance(isolate, instance);
   return isolate->heap()->ToBoolean(true);
 }
 
 }  // namespace internal
 }  // namespace v8