Eliminate special keyed load string stub in favor of uniform handlers.

src/x64/code-stubs-x64.cc

 // Copyright 2013 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.
 
 #include "src/v8.h"
 
 #if V8_TARGET_ARCH_X64
 
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
@@ skipping 849 matching lines @@
       ExternalReference(IC_Utility(IC::kLoadElementWithInterceptor),
                         masm->isolate()),
       2, 1);
 
   __ bind(&slow);
   PropertyAccessCompiler::TailCallBuiltin(
       masm, PropertyAccessCompiler::MissBuiltin(Code::KEYED_LOAD_IC));
 }
 
 
+void LoadIndexedStringStub::Generate(MacroAssembler* masm) {
+  // Return address is on the stack.
+  Label miss;
+
+  Register receiver = LoadDescriptor::ReceiverRegister();
+  Register index = LoadDescriptor::NameRegister();
+  Register scratch = rbx;
+  Register result = rax;
+  DCHECK(!scratch.is(receiver) && !scratch.is(index));
+
+  StringCharAtGenerator char_at_generator(receiver, index, scratch, result,
+                                          &miss,  // When not a string.
+                                          &miss,  // When not a number.
+                                          &miss,  // When index out of range.
+                                          STRING_INDEX_IS_ARRAY_INDEX,
+                                          RECEIVER_IS_STRING);
+  char_at_generator.GenerateFast(masm);
+  __ ret(0);
+
+  StubRuntimeCallHelper call_helper;
+  char_at_generator.GenerateSlow(masm, call_helper);
+
+  __ bind(&miss);
+  PropertyAccessCompiler::TailCallBuiltin(
+      masm, PropertyAccessCompiler::MissBuiltin(Code::KEYED_LOAD_IC));
+}
+
+
 void ArgumentsAccessStub::GenerateNewStrict(MacroAssembler* masm) {
   // rsp[0]  : return address
   // rsp[8]  : number of parameters
   // rsp[16] : receiver displacement
   // rsp[24] : function
 
   // Check if the calling frame is an arguments adaptor frame.
   Label adaptor_frame, try_allocate, runtime;
   __ movp(rdx, Operand(rbp, StandardFrameConstants::kCallerFPOffset));
   __ movp(rcx, Operand(rdx, StandardFrameConstants::kContextOffset));
@@ skipping 3789 matching lines @@
                               return_value_operand,
                               NULL);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64