Remove HCompareConstantEqAndBranch (never used), and its corresponding Lithium instructions.

src/x64/lithium-codegen-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 2069 matching lines @@
     Handle<Object> right = ToHandle(LConstantOperand::cast(instr->right()));
     __ CmpObject(left, right);
   } else {
     Register right = ToRegister(instr->right());
     __ cmpq(left, right);
   }
   EmitBranch(instr, equal);
 }
 
 
-void LCodeGen::DoCmpConstantEqAndBranch(LCmpConstantEqAndBranch* instr) {
-  Register left = ToRegister(instr->left());
-
-  __ cmpq(left, Immediate(instr->hydrogen()->right()));
-  EmitBranch(instr, equal);
-}
-
-
 Condition LCodeGen::EmitIsObject(Register input,
                                  Label* is_not_object,
                                  Label* is_object) {
   ASSERT(!input.is(kScratchRegister));
 
   __ JumpIfSmi(input, is_not_object);
 
   __ CompareRoot(input, Heap::kNullValueRootIndex);
   __ j(equal, is_object);
 
@@ skipping 3430 matching lines @@
                                FixedArray::kHeaderSize - kPointerSize));
   __ bind(&done);
 }
 
 
 #undef __
 
 } }  // namespace v8::internal
 
 #endif  // V8_TARGET_ARCH_X64