Add enumeration to specify if smi check needed

src/x64/code-stubs-x64.cc

 // Copyright 2011 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 2533 matching lines @@
 
   // Calculate the entry in the number string cache. The hash value in the
   // number string cache for smis is just the smi value, and the hash for
   // doubles is the xor of the upper and lower words. See
   // Heap::GetNumberStringCache.
   Label is_smi;
   Label load_result_from_cache;
   Factory* factory = masm->isolate()->factory();
   if (!object_is_smi) {
     __ JumpIfSmi(object, &is_smi);
-    __ CheckMap(object, factory->heap_number_map(), not_found, true);
+    __ CheckMap(object,
+                factory->heap_number_map(),
+                not_found,
+                DONT_DO_SMI_CHECK);
 
     STATIC_ASSERT(8 == kDoubleSize);
     __ movl(scratch, FieldOperand(object, HeapNumber::kValueOffset + 4));
     __ xor_(scratch, FieldOperand(object, HeapNumber::kValueOffset));
     GenerateConvertHashCodeToIndex(masm, scratch, mask);
 
     Register index = scratch;
     Register probe = mask;
     __ movq(probe,
             FieldOperand(number_string_cache,
@@ skipping 1109 matching lines @@
 
 
 void StringCharCodeAtGenerator::GenerateSlow(
     MacroAssembler* masm, const RuntimeCallHelper& call_helper) {
   __ Abort("Unexpected fallthrough to CharCodeAt slow case");
 
   Factory* factory = masm->isolate()->factory();
   // Index is not a smi.
   __ bind(&index_not_smi_);
   // If index is a heap number, try converting it to an integer.
-  __ CheckMap(index_, factory->heap_number_map(), index_not_number_, true);
+  __ CheckMap(index_,
+              factory->heap_number_map(),
+              index_not_number_,
+              DONT_DO_SMI_CHECK);
   call_helper.BeforeCall(masm);
   __ push(object_);
   __ push(index_);
   __ push(index_);  // Consumed by runtime conversion function.
   if (index_flags_ == STRING_INDEX_IS_NUMBER) {
     __ CallRuntime(Runtime::kNumberToIntegerMapMinusZero, 1);
   } else {
     ASSERT(index_flags_ == STRING_INDEX_IS_ARRAY_INDEX);
     // NumberToSmi discards numbers that are not exact integers.
     __ CallRuntime(Runtime::kNumberToSmi, 1);
@@ skipping 1406 matching lines @@
   __ Drop(1);
   __ ret(2 * kPointerSize);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64