[runtime] Introduce FastNewStrictArgumentsStub to optimize strict arguments.

src/code-stubs.h

 // 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.
 
 #ifndef V8_CODE_STUBS_H_
 #define V8_CODE_STUBS_H_
 
 #include "src/allocation.h"
 #include "src/assembler.h"
 #include "src/codegen.h"
@@ skipping 60 matching lines @@
   V(CompareNilIC)                           \
   V(CreateAllocationSite)                   \
   V(CreateWeakCell)                         \
   V(ElementsTransitionAndStore)             \
   V(FastCloneRegExp)                        \
   V(FastCloneShallowArray)                  \
   V(FastCloneShallowObject)                 \
   V(FastNewClosure)                         \
   V(FastNewContext)                         \
   V(FastNewRestParameter)                   \
+  V(FastNewStrictArguments)               \
   V(GrowArrayElements)                      \
   V(InternalArrayNArgumentsConstructor)     \
   V(InternalArrayNoArgumentConstructor)     \
   V(InternalArraySingleArgumentConstructor) \
   V(KeyedLoadGeneric)                       \
   V(LoadGlobalViaContext)                   \
   V(LoadScriptContextField)                 \
   V(LoadDictionaryElement)                  \
   V(NameDictionaryLookup)                   \
   V(NumberToString)                         \
@@ skipping 641 matching lines @@
 class FastNewRestParameterStub final : public PlatformCodeStub {
  public:
   explicit FastNewRestParameterStub(Isolate* isolate)
       : PlatformCodeStub(isolate) {}
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(FastNewRestParameter);
   DEFINE_PLATFORM_CODE_STUB(FastNewRestParameter, PlatformCodeStub);
 };
 
 
+// TODO(turbofan): This stub should be possible to write in TurboFan
+// using the CodeStubAssembler very soon in a way that is as efficient
+// and easy as the current handwritten version, which is partly a copy
+// of the strict arguments object materialization code.
+class FastNewStrictArgumentsStub final : public PlatformCodeStub {
+ public:
+  explicit FastNewStrictArgumentsStub(Isolate* isolate)
+      : PlatformCodeStub(isolate) {}
+
+  DEFINE_CALL_INTERFACE_DESCRIPTOR(FastNewStrictArguments);
+  DEFINE_PLATFORM_CODE_STUB(FastNewStrictArguments, PlatformCodeStub);
+};
+
+
 class FastCloneRegExpStub final : public HydrogenCodeStub {
  public:
   explicit FastCloneRegExpStub(Isolate* isolate) : HydrogenCodeStub(isolate) {}
 
  private:
   DEFINE_CALL_INTERFACE_DESCRIPTOR(FastCloneRegExp);
   DEFINE_HYDROGEN_CODE_STUB(FastCloneRegExp, HydrogenCodeStub);
 };
 
 
@@ skipping 1072 matching lines @@
   DEFINE_PLATFORM_CODE_STUB(JSEntry, PlatformCodeStub);
 };
 
 
 class ArgumentsAccessStub: public PlatformCodeStub {
  public:
   enum Type {
     READ_ELEMENT,
     NEW_SLOPPY_FAST,
     NEW_SLOPPY_SLOW,
-    NEW_STRICT
   };
 
   ArgumentsAccessStub(Isolate* isolate, Type type) : PlatformCodeStub(isolate) {
     minor_key_ = TypeBits::encode(type);
   }
 
   CallInterfaceDescriptor GetCallInterfaceDescriptor() const override {
     if (type() == READ_ELEMENT) {
       return ArgumentsAccessReadDescriptor(isolate());
     } else {
       return ArgumentsAccessNewDescriptor(isolate());
     }
   }
 
-  static Type ComputeType(bool is_unmapped, bool has_duplicate_parameters) {
-    if (is_unmapped) {
-      return Type::NEW_STRICT;
-    } else if (has_duplicate_parameters) {
+  static Type ComputeType(bool has_duplicate_parameters) {
+    if (has_duplicate_parameters) {
       return Type::NEW_SLOPPY_SLOW;
     } else {
       return Type::NEW_SLOPPY_FAST;
     }
   }
 
  private:
   Type type() const { return TypeBits::decode(minor_key_); }
 
   void GenerateReadElement(MacroAssembler* masm);
-  void GenerateNewStrict(MacroAssembler* masm);
   void GenerateNewSloppyFast(MacroAssembler* masm);
   void GenerateNewSloppySlow(MacroAssembler* masm);
 
   void PrintName(std::ostream& os) const override;  // NOLINT
 
   class TypeBits : public BitField<Type, 0, 2> {};
 
   DEFINE_PLATFORM_CODE_STUB(ArgumentsAccess, PlatformCodeStub);
 };
 
@@ skipping 1118 matching lines @@
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 
 extern Representation RepresentationFromType(Type* type);
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CODE_STUBS_H_