Optimized TurboFan support for rest args.

R=bmeurer@chromium.org
BUG=

Review URL: https://codereview.chromium.org/1557883002

Cr-Commit-Position: refs/heads/master@{#33105}

src/code-factory.cc

@@ -281,6 +281,13 @@ Callable CodeFactory::ArgumentsAccess(Isolate* isolate,
 }
 
 
+// static
+Callable CodeFactory::RestArgumentsAccess(Isolate* isolate) {
+  RestParamAccessStub stub(isolate);
+  return Callable(stub.GetCode(), stub.GetCallInterfaceDescriptor());
+}
+
+
 // static
 Callable CodeFactory::AllocateHeapNumber(Isolate* isolate) {
   AllocateHeapNumberStub stub(isolate);

src/code-factory.h

@@ -94,6 +94,7 @@ class CodeFactory final {
 
   static Callable ArgumentsAccess(Isolate* isolate, bool is_unmapped_arguments,
                                   bool has_duplicate_parameters);
+  static Callable RestArgumentsAccess(Isolate* isolate);
 
   static Callable AllocateHeapNumber(Isolate* isolate);
   static Callable AllocateMutableHeapNumber(Isolate* isolate);

src/compiler/js-typed-lowering.h

@@ -95,6 +95,8 @@ class JSTypedLowering final : public AdvancedReducer {
 
   Node* Word32Shl(Node* const lhs, int32_t const rhs);
   Node* AllocateArguments(Node* effect, Node* control, Node* frame_state);
+  Node* AllocateRestArguments(Node* effect, Node* control, Node* frame_state,
+                              int start_index);
   Node* AllocateAliasedArguments(Node* effect, Node* control, Node* frame_state,
                                  Node* context, Handle<SharedFunctionInfo>,
                                  bool* has_aliased_arguments);

test/unittests/compiler/js-typed-lowering-unittest.cc

@@ -952,6 +952,25 @@ TEST_F(JSTypedLoweringTest, JSCreateArgumentsViaStub) {
 }
 
 
+TEST_F(JSTypedLoweringTest, JSCreateArgumentsRestArrayViaStub) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state = FrameState(shared, graph()->start());
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsParameters::kRestArray, 0),
+      closure, context, frame_state, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(
+      r.replacement(),
+      IsCall(_,
+             IsHeapConstant(CodeFactory::RestArgumentsAccess(isolate()).code()),
+             IsNumberConstant(0), _, IsNumberConstant(0), _, effect, control));
+}
+
+
 TEST_F(JSTypedLoweringTest, JSCreateArgumentsInlinedMapped) {
   Node* const closure = Parameter(Type::Any());
   Node* const context = UndefinedConstant();
@@ -968,7 +987,7 @@ TEST_F(JSTypedLoweringTest, JSCreateArgumentsInlinedMapped) {
   EXPECT_THAT(r.replacement(),
               IsFinishRegion(
                   IsAllocate(IsNumberConstant(Heap::kSloppyArgumentsObjectSize),
-                             IsBeginRegion(effect), control),
+                             _, control),
                   _));
 }
 
@@ -989,11 +1008,29 @@ TEST_F(JSTypedLoweringTest, JSCreateArgumentsInlinedUnmapped) {
   EXPECT_THAT(r.replacement(),
               IsFinishRegion(
                   IsAllocate(IsNumberConstant(Heap::kStrictArgumentsObjectSize),
-                             IsBeginRegion(effect), control),
+                             _, control),
                   _));
 }
 
 
+TEST_F(JSTypedLoweringTest, JSCreateArgumentsInlinedRestArray) {
+  Node* const closure = Parameter(Type::Any());
+  Node* const context = UndefinedConstant();
+  Node* const effect = graph()->start();
+  Node* const control = graph()->start();
+  Handle<SharedFunctionInfo> shared(isolate()->object_function()->shared());
+  Node* const frame_state_outer = FrameState(shared, graph()->start());
+  Node* const frame_state_inner = FrameState(shared, frame_state_outer);
+  Reduction r = Reduce(graph()->NewNode(
+      javascript()->CreateArguments(CreateArgumentsParameters::kRestArray, 0),
+      closure, context, frame_state_inner, effect, control));
+  ASSERT_TRUE(r.Changed());
+  EXPECT_THAT(r.replacement(),
+              IsFinishRegion(
+                  IsAllocate(IsNumberConstant(JSArray::kSize), _, control), _));
+}
+
+
 // -----------------------------------------------------------------------------
 // JSCreateClosure