Refactor type checks in v8natives.js and runtime.js....

src/x64/codegen-x64.cc

 // Copyright 2010 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 5705 matching lines @@
   __ movzxbq(kScratchRegister,
              FieldOperand(kScratchRegister, Map::kInstanceTypeOffset));
   __ cmpq(kScratchRegister, Immediate(FIRST_JS_OBJECT_TYPE));
   destination()->false_target()->Branch(below);
   __ cmpq(kScratchRegister, Immediate(LAST_JS_OBJECT_TYPE));
   obj.Unuse();
   destination()->Split(below_equal);
 }
 
 
+void CodeGenerator::GenerateIsSpecObject(ZoneList<Expression*>* args) {
+  // This generates a fast version of:
+  // (typeof(arg) === 'object' || %_ClassOf(arg) == 'RegExp' ||
+  // typeof(arg) == function).
+  // It includes undetectable objects (as opposed to IsObject).
+  ASSERT(args->length() == 1);
+  Load(args->at(0));
+  Result value = frame_->Pop();
+  value.ToRegister();
+  ASSERT(value.is_valid());
+  Condition is_smi = masm_->CheckSmi(value.reg());
+  destination()->false_target()->Branch(is_smi);
+  // Check that this is an object.
+  __ CmpObjectType(value.reg(), FIRST_JS_OBJECT_TYPE, kScratchRegister);
+  value.Unuse();
+  destination()->Split(above_equal);
+}
+
+
 void CodeGenerator::GenerateIsFunction(ZoneList<Expression*>* args) {
   // This generates a fast version of:
   // (%_ClassOf(arg) === 'Function')
   ASSERT(args->length() == 1);
   Load(args->at(0));
   Result obj = frame_->Pop();
   obj.ToRegister();
   Condition is_smi = masm_->CheckSmi(obj.reg());
   destination()->false_target()->Branch(is_smi);
   __ CmpObjectType(obj.reg(), JS_FUNCTION_TYPE, kScratchRegister);
@@ skipping 6364 matching lines @@
 #undef __
 
 void RecordWriteStub::Generate(MacroAssembler* masm) {
   masm->RecordWriteHelper(object_, addr_, scratch_);
   masm->ret(0);
 }
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64