Merge bleeding_edge r17376:17693.

src/code-stubs-hydrogen.cc

Index: src/code-stubs-hydrogen.cc
diff --git a/src/code-stubs-hydrogen.cc b/src/code-stubs-hydrogen.cc
index 88af4665b684410fa046ec6dd662ceb0dc2e6fd1..a7901796966b42c23e1a64d1a8bbab01ab4c2261 100644
--- a/src/code-stubs-hydrogen.cc
+++ b/src/code-stubs-hydrogen.cc
@@ -150,26 +150,24 @@ bool CodeStubGraphBuilderBase::BuildGraph() {
   next_block->SetJoinId(BailoutId::StubEntry());
   set_current_block(next_block);
 
+  bool runtime_stack_params = descriptor_->stack_parameter_count_.is_valid();
+  HInstruction* stack_parameter_count = NULL;
   for (int i = 0; i < param_count; ++i) {
-    HParameter* param =
-        Add<HParameter>(i, HParameter::REGISTER_PARAMETER);
+    Representation r = descriptor_->IsParameterCountRegister(i)
+        ? Representation::Integer32()
+        : Representation::Tagged();
+    HParameter* param = Add<HParameter>(i, HParameter::REGISTER_PARAMETER, r);
     start_environment->Bind(i, param);
     parameters_[i] = param;
+    if (descriptor_->IsParameterCountRegister(i)) {
+      param->set_type(HType::Smi());
+      stack_parameter_count = param;
+      arguments_length_ = stack_parameter_count;
+    }
   }
 
-  HInstruction* stack_parameter_count;
-  if (descriptor_->stack_parameter_count_.is_valid()) {
-    ASSERT(descriptor_->environment_length() == (param_count + 1));
-    stack_parameter_count = New<HParameter>(param_count,
-                                            HParameter::REGISTER_PARAMETER,
-                                            Representation::Integer32());
-    stack_parameter_count->set_type(HType::Smi());
-    // It's essential to bind this value to the environment in case of deopt.
-    AddInstruction(stack_parameter_count);
-    start_environment->Bind(param_count, stack_parameter_count);
-    arguments_length_ = stack_parameter_count;
-  } else {
-    ASSERT(descriptor_->environment_length() == param_count);
+  ASSERT(!runtime_stack_params || arguments_length_ != NULL);
+  if (!runtime_stack_params) {
     stack_parameter_count = graph()->GetConstantMinus1();
     arguments_length_ = graph()->GetConstant0();
   }
@@ -189,10 +187,11 @@ bool CodeStubGraphBuilderBase::BuildGraph() {
   if (descriptor_->function_mode_ == JS_FUNCTION_STUB_MODE) {
     if (!stack_parameter_count->IsConstant() &&
         descriptor_->hint_stack_parameter_count_ < 0) {
-      HInstruction* amount = graph()->GetConstant1();
-      stack_pop_count = Add<HAdd>(stack_parameter_count, amount);
-      stack_pop_count->ChangeRepresentation(Representation::Integer32());
+      HInstruction* constant_one = graph()->GetConstant1();
+      stack_pop_count = Add<HAdd>(stack_parameter_count, constant_one);
       stack_pop_count->ClearFlag(HValue::kCanOverflow);
+      // TODO(mvstanton): verify that stack_parameter_count+1 really fits in a
+      // smi.
     } else {
       int count = descriptor_->hint_stack_parameter_count_;
       stack_pop_count = Add<HConstant>(count);
@@ -371,7 +370,8 @@ HValue* CodeStubGraphBuilder<FastCloneShallowArrayStub>::BuildCodeStub() {
                                                     undefined);
   checker.Then();
 
-  HObjectAccess access = HObjectAccess::ForAllocationSiteTransitionInfo();
+  HObjectAccess access = HObjectAccess::ForAllocationSiteOffset(
+      AllocationSite::kTransitionInfoOffset);
   HInstruction* boilerplate = Add<HLoadNamedField>(allocation_site, access);
   HValue* push_value;
   if (mode == FastCloneShallowArrayStub::CLONE_ANY_ELEMENTS) {
@@ -440,7 +440,8 @@ HValue* CodeStubGraphBuilder<FastCloneShallowObjectStub>::BuildCodeStub() {
                                                     undefined);
   checker.And();
 
-  HObjectAccess access = HObjectAccess::ForAllocationSiteTransitionInfo();
+  HObjectAccess access = HObjectAccess::ForAllocationSiteOffset(
+      AllocationSite::kTransitionInfoOffset);
   HInstruction* boilerplate = Add<HLoadNamedField>(allocation_site, access);
 
   int size = JSObject::kHeaderSize + casted_stub()->length() * kPointerSize;
@@ -500,12 +501,14 @@ HValue* CodeStubGraphBuilder<CreateAllocationSiteStub>::BuildCodeStub() {
   // Store the payload (smi elements kind)
   HValue* initial_elements_kind = Add<HConstant>(GetInitialFastElementsKind());
   Add<HStoreNamedField>(object,
-                        HObjectAccess::ForAllocationSiteTransitionInfo(),
+                        HObjectAccess::ForAllocationSiteOffset(
+                            AllocationSite::kTransitionInfoOffset),
                         initial_elements_kind);
 
   // Unlike literals, constructed arrays don't have nested sites
   Add<HStoreNamedField>(object,
-                        HObjectAccess::ForAllocationSiteNestedSite(),
+                        HObjectAccess::ForAllocationSiteOffset(
+                            AllocationSite::kNestedSiteOffset),
                         graph()->GetConstant0());
 
   // Store an empty fixed array for the code dependency.
@@ -513,7 +516,8 @@ HValue* CodeStubGraphBuilder<CreateAllocationSiteStub>::BuildCodeStub() {
     Add<HConstant>(isolate()->factory()->empty_fixed_array());
   HStoreNamedField* store = Add<HStoreNamedField>(
       object,
-      HObjectAccess::ForAllocationSiteDependentCode(),
+      HObjectAccess::ForAllocationSiteOffset(
+          AllocationSite::kDependentCodeOffset),
       empty_fixed_array);
 
   // Link the object to the allocation site list
@@ -522,8 +526,8 @@ HValue* CodeStubGraphBuilder<CreateAllocationSiteStub>::BuildCodeStub() {
   HValue* site = Add<HLoadNamedField>(site_list,
                                       HObjectAccess::ForAllocationSiteList());
   store = Add<HStoreNamedField>(object,
-                                HObjectAccess::ForAllocationSiteWeakNext(),
-                                site);
+      HObjectAccess::ForAllocationSiteOffset(AllocationSite::kWeakNextOffset),
+      site);
   store->SkipWriteBarrier();
   Add<HStoreNamedField>(site_list, HObjectAccess::ForAllocationSiteList(),
                         object);
@@ -967,6 +971,38 @@ Handle<Code> BinaryOpStub::GenerateCode(Isolate* isolate) {
 
 
 template <>
+HValue* CodeStubGraphBuilder<NewStringAddStub>::BuildCodeInitializedStub() {
+  NewStringAddStub* stub = casted_stub();
+  StringAddFlags flags = stub->flags();
+  PretenureFlag pretenure_flag = stub->pretenure_flag();
+
+  HValue* left = GetParameter(NewStringAddStub::kLeft);
+  HValue* right = GetParameter(NewStringAddStub::kRight);
+
+  // Make sure that both arguments are strings if not known in advance.
+  if ((flags & STRING_ADD_CHECK_LEFT) == STRING_ADD_CHECK_LEFT) {
+    IfBuilder if_leftnotstring(this);
+    if_leftnotstring.IfNot<HIsStringAndBranch>(left);
+    if_leftnotstring.Then();
+    if_leftnotstring.Deopt("Expected string for LHS of string addition");
+  }
+  if ((flags & STRING_ADD_CHECK_RIGHT) == STRING_ADD_CHECK_RIGHT) {
+    IfBuilder if_rightnotstring(this);
+    if_rightnotstring.IfNot<HIsStringAndBranch>(right);
+    if_rightnotstring.Then();
+    if_rightnotstring.Deopt("Expected string for RHS of string addition");
+  }
+
+  return BuildStringAdd(left, right, pretenure_flag);
+}
+
+
+Handle<Code> NewStringAddStub::GenerateCode(Isolate* isolate) {
+  return DoGenerateCode(isolate, this);
+}
+
+
+template <>
 HValue* CodeStubGraphBuilder<ToBooleanStub>::BuildCodeInitializedStub() {
   ToBooleanStub* stub = casted_stub();
 
@@ -1236,8 +1272,6 @@ HValue* CodeStubGraphBuilder<FastNewClosureStub>::BuildCodeStub() {
                         HObjectAccess::ForSharedFunctionInfoPointer(),
                         shared_info);
   Add<HStoreNamedField>(js_function, HObjectAccess::ForFunctionContextPointer(),
-                        shared_info);
-  Add<HStoreNamedField>(js_function, HObjectAccess::ForFunctionContextPointer(),
                         context());
 
   // Initialize the code pointer in the function to be the one