[crankshaft] Remove the useless HMapEnumLength instruction.

src/crankshaft/hydrogen-instructions.h

 // 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.
 
 #ifndef V8_CRANKSHAFT_HYDROGEN_INSTRUCTIONS_H_
 #define V8_CRANKSHAFT_HYDROGEN_INSTRUCTIONS_H_
 
 #include <cstring>
 #include <iosfwd>
 
@@ skipping 99 matching lines @@
   V(LeaveInlined)                             \
   V(LoadContextSlot)                          \
   V(LoadFieldByIndex)                         \
   V(LoadFunctionPrototype)                    \
   V(LoadGlobalGeneric)                        \
   V(LoadKeyed)                                \
   V(LoadKeyedGeneric)                         \
   V(LoadNamedField)                           \
   V(LoadNamedGeneric)                         \
   V(LoadRoot)                                 \
-  V(MapEnumLength)                            \
   V(MathFloorOfDiv)                           \
   V(MathMinMax)                               \
   V(MaybeGrowElements)                        \
   V(Mod)                                      \
   V(Mul)                                      \
   V(OsrEntry)                                 \
   V(Parameter)                                \
   V(Power)                                    \
   V(Prologue)                                 \
   V(PushArguments)                            \
@@ skipping 2355 matching lines @@
         c_function_(c_function),
         save_doubles_(kDontSaveFPRegs) {
     SetOperandAt(0, context);
   }
 
   const Runtime::Function* c_function_;
   SaveFPRegsMode save_doubles_;
 };
 
 
-class HMapEnumLength final : public HUnaryOperation {
- public:
-  DECLARE_INSTRUCTION_FACTORY_P1(HMapEnumLength, HValue*);
-
-  Representation RequiredInputRepresentation(int index) override {
-    return Representation::Tagged();
-  }
-
-  DECLARE_CONCRETE_INSTRUCTION(MapEnumLength)
-
- protected:
-  bool DataEquals(HValue* other) override { return true; }
-
- private:
-  explicit HMapEnumLength(HValue* value)
-      : HUnaryOperation(value, HType::Smi()) {
-    set_representation(Representation::Smi());
-    SetFlag(kUseGVN);
-    SetDependsOnFlag(kMaps);
-  }
-
-  bool IsDeletable() const override { return true; }
-};
-
-
 class HUnaryMathOperation final : public HTemplateInstruction<2> {
  public:
   static HInstruction* New(Isolate* isolate, Zone* zone, HValue* context,
                            HValue* value, BuiltinFunctionId op);
 
   HValue* context() const { return OperandAt(0); }
   HValue* value() const { return OperandAt(1); }
 
   std::ostream& PrintDataTo(std::ostream& os) const override;  // NOLINT
 
@@ skipping 3489 matching lines @@
                          Map::kBitFieldOffset,
                          Representation::UInteger8());
   }
 
   static HObjectAccess ForMapBitField2() {
     return HObjectAccess(kInobject,
                          Map::kBitField2Offset,
                          Representation::UInteger8());
   }
 
+  static HObjectAccess ForMapBitField3() {
+    return HObjectAccess(kInobject, Map::kBitField3Offset,
+                         Representation::Integer32());
+  }
+
   static HObjectAccess ForNameHashField() {
     return HObjectAccess(kInobject,
                          Name::kHashFieldOffset,
                          Representation::Integer32());
   }
 
   static HObjectAccess ForMapInstanceTypeAndBitField() {
     STATIC_ASSERT((Map::kInstanceTypeAndBitFieldOffset & 1) == 0);
     // Ensure the two fields share one 16-bit word, endian-independent.
     STATIC_ASSERT((Map::kBitFieldOffset & ~1) ==
@@ skipping 1769 matching lines @@
 
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CRANKSHAFT_HYDROGEN_INSTRUCTIONS_H_