[intrinsics] Kill the %_IsMinusZero intrinsic.

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 61 matching lines @@
   V(CheckInstanceType)                        \
   V(CheckMaps)                                \
   V(CheckMapValue)                            \
   V(CheckSmi)                                 \
   V(CheckValue)                               \
   V(ClampToUint8)                             \
   V(ClassOfTestAndBranch)                     \
   V(CompareNumericAndBranch)                  \
   V(CompareHoleAndBranch)                     \
   V(CompareGeneric)                           \
-  V(CompareMinusZeroAndBranch)                \
   V(CompareObjectEqAndBranch)                 \
   V(CompareMap)                               \
   V(Constant)                                 \
   V(ConstructDouble)                          \
   V(Context)                                  \
   V(DebugBreak)                               \
   V(DeclareGlobals)                           \
   V(Deoptimize)                               \
   V(Div)                                      \
   V(DoubleBits)                               \
@@ skipping 4245 matching lines @@
   HCompareHoleAndBranch(HValue* value,
                         HBasicBlock* true_target = NULL,
                         HBasicBlock* false_target = NULL)
       : HUnaryControlInstruction(value, true_target, false_target) {
     SetFlag(kFlexibleRepresentation);
     SetFlag(kAllowUndefinedAsNaN);
   }
 };
 
 
-class HCompareMinusZeroAndBranch final : public HUnaryControlInstruction {
- public:
-  DECLARE_INSTRUCTION_FACTORY_P1(HCompareMinusZeroAndBranch, HValue*);
-
-  void InferRepresentation(HInferRepresentationPhase* h_infer) override;
-
-  Representation RequiredInputRepresentation(int index) override {
-    return representation();
-  }
-
-  bool KnownSuccessorBlock(HBasicBlock** block) override;
-
-  DECLARE_CONCRETE_INSTRUCTION(CompareMinusZeroAndBranch)
-
- private:
-  explicit HCompareMinusZeroAndBranch(HValue* value)
-      : HUnaryControlInstruction(value, NULL, NULL) {
-  }
-};
-
-
 class HCompareObjectEqAndBranch : public HTemplateControlInstruction<2, 2> {
  public:
   DECLARE_INSTRUCTION_FACTORY_P2(HCompareObjectEqAndBranch, HValue*, HValue*);
   DECLARE_INSTRUCTION_FACTORY_P4(HCompareObjectEqAndBranch, HValue*, HValue*,
                                  HBasicBlock*, HBasicBlock*);
 
   bool KnownSuccessorBlock(HBasicBlock** block) override;
 
   static const int kNoKnownSuccessorIndex = -1;
   int known_successor_index() const { return known_successor_index_; }
@@ skipping 3422 matching lines @@
 
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_CRANKSHAFT_HYDROGEN_INSTRUCTIONS_H_