[crankshaft] Remove the useless HMapEnumLength instruction.

src/crankshaft/mips/lithium-mips.cc

 // Copyright 2012 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/crankshaft/mips/lithium-mips.h"
 
 #include <sstream>
 
 #if V8_TARGET_ARCH_MIPS
 
@@ skipping 1748 matching lines @@
 
 
 LInstruction* LChunkBuilder::DoClassOfTestAndBranch(
     HClassOfTestAndBranch* instr) {
   DCHECK(instr->value()->representation().IsTagged());
   return new(zone()) LClassOfTestAndBranch(UseRegister(instr->value()),
                                            TempRegister());
 }
 
 
-LInstruction* LChunkBuilder::DoMapEnumLength(HMapEnumLength* instr) {
-  LOperand* map = UseRegisterAtStart(instr->value());
-  return DefineAsRegister(new(zone()) LMapEnumLength(map));
-}
-
-
 LInstruction* LChunkBuilder::DoSeqStringGetChar(HSeqStringGetChar* instr) {
   LOperand* string = UseRegisterAtStart(instr->string());
   LOperand* index = UseRegisterOrConstantAtStart(instr->index());
   return DefineAsRegister(new(zone()) LSeqStringGetChar(string, index));
 }
 
 
 LInstruction* LChunkBuilder::DoSeqStringSetChar(HSeqStringSetChar* instr) {
   LOperand* string = UseRegisterAtStart(instr->string());
   LOperand* index = FLAG_debug_code
@@ skipping 791 matching lines @@
   LOperand* function = UseRegisterAtStart(instr->function());
   LAllocateBlockContext* result =
       new(zone()) LAllocateBlockContext(context, function);
   return MarkAsCall(DefineFixed(result, cp), instr);
 }
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS