Inline number to string conversion for string addition into BinaryOp(Stub).

src/x64/code-stubs-x64.cc

 // Copyright 2013 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 48 matching lines @@
   descriptor->deoptimization_handler_ = NULL;
 }
 
 
 void NumberToStringStub::InitializeInterfaceDescriptor(
     Isolate* isolate,
     CodeStubInterfaceDescriptor* descriptor) {
   static Register registers[] = { rax };
   descriptor->register_param_count_ = 1;
   descriptor->register_params_ = registers;
-  descriptor->deoptimization_handler_ = NULL;
+  descriptor->deoptimization_handler_ =
+      Runtime::FunctionForId(Runtime::kNumberToString)->entry;
 }
 
 
 void FastCloneShallowArrayStub::InitializeInterfaceDescriptor(
     Isolate* isolate,
     CodeStubInterfaceDescriptor* descriptor) {
   static Register registers[] = { rax, rbx, rcx };
   descriptor->register_param_count_ = 3;
   descriptor->register_params_ = registers;
   descriptor->deoptimization_handler_ =
@@ skipping 5757 matching lines @@
   __ bind(&fast_elements_case);
   GenerateCase(masm, FAST_ELEMENTS);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64