Call JS functions via native context instead of js builtins object.

src/compiler/ast-graph-builder.cc

Index: src/compiler/ast-graph-builder.cc
diff --git a/src/compiler/ast-graph-builder.cc b/src/compiler/ast-graph-builder.cc
index 11dc456e3dba721637e06a9283906a6db530255c..0fb0e7e5f52c1e2597447c27cd76a73d4df03b57 100644
--- a/src/compiler/ast-graph-builder.cc
+++ b/src/compiler/ast-graph-builder.cc
@@ -2538,20 +2538,18 @@ void AstGraphBuilder::VisitCallNew(CallNew* expr) {
 
 
 void AstGraphBuilder::VisitCallJSRuntime(CallRuntime* expr) {
-  Handle<String> name = expr->name();
-
   // The callee and the receiver both have to be pushed onto the operand stack
   // before arguments are being evaluated.
   CallFunctionFlags flags = NO_CALL_FUNCTION_FLAGS;
-  Node* receiver_value = BuildLoadBuiltinsObject();
-  VectorSlotPair pair = CreateVectorSlotPair(expr->CallRuntimeFeedbackSlot());
-  // TODO(jarin): bailout ids for runtime calls.
-  FrameStateBeforeAndAfter states(this, BailoutId::None());
-  Node* callee_value = BuildNamedLoad(receiver_value, name, pair);
-  states.AddToNode(callee_value, BailoutId::None(),
-                   OutputFrameStateCombine::Push());
+  Node* global = BuildLoadGlobalObject();
+  Node* native_context =
+      BuildLoadObjectField(global, GlobalObject::kNativeContextOffset);
+  Node* callee_value =
+      NewNode(javascript()->LoadContext(0, expr->context_index(), true),
+              native_context);
+
   environment()->Push(callee_value);
-  environment()->Push(receiver_value);
+  environment()->Push(jsgraph()->UndefinedConstant());

[Michael Starzinger, 2015/08/26 09:43:21]

nit: Let's add a trailing "// receiver" comment, or alternatively use a local
variable called "receiver_value", both are fine with me.

[Yang, 2015/08/26 10:27:30]

Done.

 
   // Evaluate all arguments to the JS runtime call.
   ZoneList<Expression*>* args = expr->arguments();
@@ -2567,15 +2565,14 @@ void AstGraphBuilder::VisitCallJSRuntime(CallRuntime* expr) {
 
 
 void AstGraphBuilder::VisitCallRuntime(CallRuntime* expr) {
-  const Runtime::Function* function = expr->function();
-
   // Handle calls to runtime functions implemented in JavaScript separately as
   // the call follows JavaScript ABI and the callee is statically unknown.
   if (expr->is_jsruntime()) {
-    DCHECK(function == NULL && expr->name()->length() > 0);
     return VisitCallJSRuntime(expr);
   }
 
+  const Runtime::Function* function = expr->function();
+
   // TODO(mstarzinger): This bailout is a gigantic hack, the owner is ashamed.
   if (function->function_id == Runtime::kInlineGeneratorNext ||
       function->function_id == Runtime::kInlineGeneratorThrow) {