Add an IC for CompareNil operations

src/hydrogen-instructions.h

 // Copyright 2012 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 110 matching lines @@
   V(HasCachedArrayIndexAndBranch)              \
   V(HasInstanceTypeAndBranch)                  \
   V(InductionVariableAnnotation)               \
   V(In)                                        \
   V(InnerAllocatedObject)                      \
   V(InstanceOf)                                \
   V(InstanceOfKnownGlobal)                     \
   V(InstanceSize)                              \
   V(InvokeFunction)                            \
   V(IsConstructCallAndBranch)                  \
-  V(IsNilAndBranch)                            \
   V(IsObjectAndBranch)                         \
   V(IsStringAndBranch)                         \
   V(IsSmiAndBranch)                            \
   V(IsUndetectableAndBranch)                   \
   V(LeaveInlined)                              \
   V(LoadContextSlot)                           \
   V(LoadElements)                              \
   V(LoadExternalArrayPointer)                  \
   V(LoadFunctionPrototype)                     \
   V(LoadGlobalCell)                            \
@@ skipping 3783 matching lines @@
 
   HValue* left() { return OperandAt(0); }
   HValue* right() { return OperandAt(1); }
 
   virtual void PrintDataTo(StringStream* stream);
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
   }
 
+  virtual Representation observed_input_representation(int index) {
+    return Representation::Tagged();
+  }
+
   DECLARE_CONCRETE_INSTRUCTION(CompareObjectEqAndBranch)
 };
 
 
 class HCompareConstantEqAndBranch: public HUnaryControlInstruction {
  public:
   HCompareConstantEqAndBranch(HValue* left, int right, Token::Value op)
       : HUnaryControlInstruction(left, NULL, NULL), op_(op), right_(right) {
     ASSERT(op == Token::EQ_STRICT);
   }
 
   Token::Value op() const { return op_; }
   HValue* left() { return value(); }
   int right() const { return right_; }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Integer32();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(CompareConstantEqAndBranch);
 
  private:
   const Token::Value op_;
   const int right_;
 };
 
 
-class HIsNilAndBranch: public HUnaryControlInstruction {
- public:
-  HIsNilAndBranch(HValue* value, EqualityKind kind, NilValue nil)
-      : HUnaryControlInstruction(value, NULL, NULL), kind_(kind), nil_(nil) { }
-
-  EqualityKind kind() const { return kind_; }
-  NilValue nil() const { return nil_; }
-
-  virtual void PrintDataTo(StringStream* stream);
-
-  virtual Representation RequiredInputRepresentation(int index) {
-    return Representation::Tagged();
-  }
-  virtual Representation observed_input_representation(int index) {
-    return Representation::Tagged();
-  }
-
-  DECLARE_CONCRETE_INSTRUCTION(IsNilAndBranch)
-
- private:
-  EqualityKind kind_;
-  NilValue nil_;
-};
-
-
 class HIsObjectAndBranch: public HUnaryControlInstruction {
  public:
   explicit HIsObjectAndBranch(HValue* value)
     : HUnaryControlInstruction(value, NULL, NULL) { }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(IsObjectAndBranch)
@@ skipping 2492 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_