Optimize the typeof operator.

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 61 matching lines @@
   V(InternalArrayNArgumentsConstructor)     \
   V(InternalArrayNoArgumentConstructor)     \
   V(InternalArraySingleArgumentConstructor) \
   V(KeyedLoadGeneric)                       \
   V(LoadScriptContextField)                 \
   V(LoadDictionaryElement)                  \
   V(LoadFastElement)                        \
   V(MegamorphicLoad)                        \
   V(NameDictionaryLookup)                   \
   V(NumberToString)                         \
+  V(Typeof)                                 \
   V(RegExpConstructResult)                  \
   V(StoreFastElement)                       \
   V(StoreScriptContextField)                \
   V(StringAdd)                              \
   V(ToBoolean)                              \
   V(TransitionElementsKind)                 \
   V(VectorRawKeyedLoad)                     \
   V(VectorRawLoad)                          \
   /* IC Handler stubs */                    \
   V(ArrayBufferViewLoadField)               \
@@ skipping 495 matching lines @@
   explicit NumberToStringStub(Isolate* isolate) : HydrogenCodeStub(isolate) {}
 
   // Parameters accessed via CodeStubGraphBuilder::GetParameter()
   static const int kNumber = 0;
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(NumberToString);
   DEFINE_HYDROGEN_CODE_STUB(NumberToString, HydrogenCodeStub);
 };
 
 
+class TypeofStub final : public HydrogenCodeStub {
+ public:
+  explicit TypeofStub(Isolate* isolate) : HydrogenCodeStub(isolate) {}
+
+  // Parameters accessed via CodeStubGraphBuilder::GetParameter()
+  static const int kObject = 0;
+
+  static void GenerateAheadOfTime(Isolate* isolate);
+
+  DEFINE_CALL_INTERFACE_DESCRIPTOR(Typeof);
+  DEFINE_HYDROGEN_CODE_STUB(Typeof, HydrogenCodeStub);
+};
+
+
 class FastNewClosureStub : public HydrogenCodeStub {
  public:
   FastNewClosureStub(Isolate* isolate, LanguageMode language_mode,
                      FunctionKind kind)
       : HydrogenCodeStub(isolate) {
     DCHECK(IsValidFunctionKind(kind));
     set_sub_minor_key(LanguageModeBits::encode(language_mode) |
                       FunctionKindBits::encode(kind));
   }
 
@@ skipping 2182 matching lines @@
 
 #undef DEFINE_CALL_INTERFACE_DESCRIPTOR
 #undef DEFINE_PLATFORM_CODE_STUB
 #undef DEFINE_HANDLER_CODE_STUB
 #undef DEFINE_HYDROGEN_CODE_STUB
 #undef DEFINE_CODE_STUB
 #undef DEFINE_CODE_STUB_BASE
 } }  // namespace v8::internal
 
 #endif  // V8_CODE_STUBS_H_