[runtime] Rewrite Function.prototype.toString in C++.

src/bootstrapper.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/bootstrapper.h"
 
 #include "src/accessors.h"
 #include "src/api-natives.h"
 #include "src/code-stubs.h"
 #include "src/extensions/externalize-string-extension.h"
@@ skipping 2495 matching lines @@
                         MaybeHandle<JSObject>(), Builtins::kArrayConcat);
 
     // Make sure that InternalArray.prototype.concat appears to be compiled.
     // The code will never be called, but inline caching for call will
     // only work if it appears to be compiled.
     concat->shared()->DontAdaptArguments();
     DCHECK(concat->is_compiled());
     // Set the lengths for the functions to satisfy ECMA-262.
     concat->shared()->set_length(1);
   }
-  // Install Function.prototype.call and apply.
+  // Install Function.prototype.apply, call, and toString.
   {
     Handle<String> key = factory()->Function_string();
     Handle<JSFunction> function =
         Handle<JSFunction>::cast(Object::GetProperty(
             handle(native_context()->global_object()), key).ToHandleChecked());
     Handle<JSObject> proto =
         Handle<JSObject>(JSObject::cast(function->instance_prototype()));
 
-    // Install the call and the apply functions.
-    Handle<JSFunction> call =
-        InstallFunction(proto, "call", JS_OBJECT_TYPE, JSObject::kHeaderSize,
-                        MaybeHandle<JSObject>(), Builtins::kFunctionCall);
-    Handle<JSFunction> apply =
-        InstallFunction(proto, "apply", JS_OBJECT_TYPE, JSObject::kHeaderSize,
-                        MaybeHandle<JSObject>(), Builtins::kFunctionApply);
-
-    // Make sure that Function.prototype.call appears to be compiled.
-    // The code will never be called, but inline caching for call will
-    // only work if it appears to be compiled.
-    apply->shared()->DontAdaptArguments();
-    call->shared()->DontAdaptArguments();
-    DCHECK(call->is_compiled());
-
-    // Set the lengths for the functions to satisfy ECMA-262.
-    apply->shared()->set_length(2);
-    call->shared()->set_length(1);
+    // Install the apply, call and toString functions.
+    SimpleInstallFunction(proto, factory()->apply_string(),
+                          Builtins::kFunctionPrototypeApply, 2, false);
+    SimpleInstallFunction(proto, factory()->call_string(),
+                          Builtins::kFunctionPrototypeCall, 1, false);
+    SimpleInstallFunction(proto, factory()->toString_string(),
+                          Builtins::kFunctionPrototypeToString, 0, false);
   }
 
   // Set up the Promise constructor.
   {
     Handle<String> key = factory()->Promise_string();
     Handle<JSFunction> function = Handle<JSFunction>::cast(
         Object::GetProperty(handle(native_context()->global_object()), key)
             .ToHandleChecked());
     JSFunction::EnsureHasInitialMap(function);
     function->initial_map()->set_instance_type(JS_PROMISE_TYPE);
@@ skipping 799 matching lines @@
 }
 
 
 // Called when the top-level V8 mutex is destroyed.
 void Bootstrapper::FreeThreadResources() {
   DCHECK(!IsActive());
 }
 
 }  // namespace internal
 }  // namespace v8