[stubs]: Convert FastNewContext stub to turbofan

src/code-stubs.cc

 // Copyright 2012 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/code-stubs.h"
 
 #include <sstream>
 
 #include "src/bootstrapper.h"
 #include "src/code-factory.h"
@@ skipping 4171 matching lines @@
     const {
   return VectorStoreTransitionDescriptor(isolate());
 }
 
 
 CallInterfaceDescriptor
 ElementsTransitionAndStoreStub::GetCallInterfaceDescriptor() const {
   return VectorStoreTransitionDescriptor(isolate());
 }
 
-void FastNewContextStub::InitializeDescriptor(CodeStubDescriptor* d) {}
-
 void TypeofStub::InitializeDescriptor(CodeStubDescriptor* descriptor) {}
 
 void NumberToStringStub::InitializeDescriptor(CodeStubDescriptor* descriptor) {
   descriptor->Initialize(
       Runtime::FunctionForId(Runtime::kNumberToString)->entry);
 }
 
 
 void FastCloneRegExpStub::InitializeDescriptor(CodeStubDescriptor* descriptor) {
   FastCloneRegExpDescriptor call_descriptor(isolate());
@@ skipping 344 matching lines @@
                                             assembler->UndefinedConstant());
 
   return result;
 }
 
 void FastNewClosureStub::GenerateAssembly(CodeStubAssembler* assembler) const {
   assembler->Return(
       Generate(assembler, assembler->Parameter(0), assembler->Parameter(1)));
 }
 
+void FastNewFunctionContextStub::GenerateAssembly(
+    CodeStubAssembler* assembler) const {
+  typedef compiler::Node Node;
+
+  int length = slots() + Context::MIN_CONTEXT_SLOTS;
+  int size = length * kPointerSize + FixedArray::kHeaderSize;
+
+  // Get the function
+  Node* function =
+      assembler->Parameter(FastNewFunctionContextDescriptor::kFunctionIndex);
+  Node* context =
+      assembler->Parameter(FastNewFunctionContextDescriptor::kContextIndex);
+
+  // Create a new closure from the given function info in new space
+  Node* function_context = assembler->Allocate(size);
+
+  assembler->StoreMapNoWriteBarrier(
+      function_context,
+      assembler->HeapConstant(isolate()->factory()->function_context_map()));
+  assembler->StoreObjectFieldNoWriteBarrier(
+      function_context, Context::kLengthOffset,
+      assembler->SmiConstant(Smi::FromInt(length)));
+
+  // Set up the fixed slots.
+  assembler->StoreFixedArrayElement(
+      function_context, assembler->Int32Constant(Context::CLOSURE_INDEX),
+      function, SKIP_WRITE_BARRIER);
+  assembler->StoreFixedArrayElement(
+      function_context, assembler->Int32Constant(Context::PREVIOUS_INDEX),
+      context, SKIP_WRITE_BARRIER);
+  assembler->StoreFixedArrayElement(
+      function_context, assembler->Int32Constant(Context::EXTENSION_INDEX),
+      assembler->TheHoleConstant(), SKIP_WRITE_BARRIER);
+
+  // Copy the native context from the previous context.
+  Node* native_context = assembler->LoadFixedArrayElement(
+      context, assembler->Int32Constant(Context::NATIVE_CONTEXT_INDEX));
+  assembler->StoreFixedArrayElement(
+      function_context, assembler->Int32Constant(Context::NATIVE_CONTEXT_INDEX),
+      native_context, SKIP_WRITE_BARRIER);
+
+  // Initialize the rest of the slots to undefined.
+  Node* undefined = assembler->UndefinedConstant();
+  for (int i = Context::MIN_CONTEXT_SLOTS; i < length; ++i) {
+    assembler->StoreFixedArrayElement(function_context,
+                                      assembler->Int32Constant(i), undefined,
+                                      SKIP_WRITE_BARRIER);
+  }
+
+  assembler->Return(function_context);
+}
+
 void CreateAllocationSiteStub::GenerateAheadOfTime(Isolate* isolate) {
   CreateAllocationSiteStub stub(isolate);
   stub.GetCode();
 }
 
 
 void CreateWeakCellStub::GenerateAheadOfTime(Isolate* isolate) {
   CreateWeakCellStub stub(isolate);
   stub.GetCode();
 }
@@ skipping 12 matching lines @@
   StoreFastElementStub(isolate, false, FAST_HOLEY_ELEMENTS,
                        STORE_AND_GROW_NO_TRANSITION).GetCode();
   for (int i = FIRST_FAST_ELEMENTS_KIND; i <= LAST_FAST_ELEMENTS_KIND; i++) {
     ElementsKind kind = static_cast<ElementsKind>(i);
     StoreFastElementStub(isolate, true, kind, STANDARD_STORE).GetCode();
     StoreFastElementStub(isolate, true, kind, STORE_AND_GROW_NO_TRANSITION)
         .GetCode();
   }
 }
 
-
 void ArrayConstructorStub::PrintName(std::ostream& os) const {  // NOLINT
   os << "ArrayConstructorStub";
   switch (argument_count()) {
     case ANY:
       os << "_Any";
       break;
     case NONE:
       os << "_None";
       break;
     case ONE:
@@ skipping 274 matching lines @@
   if (type->Is(Type::UntaggedPointer())) {
     return Representation::External();
   }
 
   DCHECK(!type->Is(Type::Untagged()));
   return Representation::Tagged();
 }
 
 }  // namespace internal
 }  // namespace v8