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

src/arm/codegen-arm.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 4742 matching lines @@
   false_target()->Branch(ne);
 
   __ ldrb(possible_object, FieldMemOperand(map_reg, Map::kInstanceTypeOffset));
   __ cmp(possible_object, Operand(FIRST_JS_OBJECT_TYPE));
   false_target()->Branch(lt);
   __ cmp(possible_object, Operand(LAST_JS_OBJECT_TYPE));
   cc_reg_ = le;
 }
 
 
+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));
+  Register value = frame_->PopToRegister();
+  __ tst(value, Operand(kSmiTagMask));
+  false_target()->Branch(eq);
+  // Check that this is an object.
+  __ ldr(value, FieldMemOperand(value, HeapObject::kMapOffset));
+  __ ldrb(value, FieldMemOperand(value, Map::kInstanceTypeOffset));
+  __ cmp(value, Operand(FIRST_JS_OBJECT_TYPE));
+  cc_reg_ = ge;
+}
+
+
 void CodeGenerator::GenerateIsFunction(ZoneList<Expression*>* args) {
   // This generates a fast version of:
   // (%_ClassOf(arg) === 'Function')
   ASSERT(args->length() == 1);
   Load(args->at(0));
   Register possible_function = frame_->PopToRegister();
   __ tst(possible_function, Operand(kSmiTagMask));
   false_target()->Branch(eq);
   Register map_reg = VirtualFrame::scratch0();
   Register scratch = VirtualFrame::scratch1();
@@ skipping 6465 matching lines @@
   __ bind(&string_add_runtime);
   __ TailCallRuntime(Runtime::kStringAdd, 2, 1);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_ARM