Revert r11420 because Win32 compilation was broken.

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 122 matching lines @@
   V(LoadFunctionPrototype)                     \
   V(LoadGlobalCell)                            \
   V(LoadGlobalGeneric)                         \
   V(LoadKeyedFastDoubleElement)                \
   V(LoadKeyedFastElement)                      \
   V(LoadKeyedGeneric)                          \
   V(LoadKeyedSpecializedArrayElement)          \
   V(LoadNamedField)                            \
   V(LoadNamedFieldPolymorphic)                 \
   V(LoadNamedGeneric)                          \
-  V(MathFloorOfDiv)                            \
   V(Mod)                                       \
   V(Mul)                                       \
   V(ObjectLiteral)                             \
   V(OsrEntry)                                  \
   V(OuterContext)                              \
   V(Parameter)                                 \
   V(Power)                                     \
   V(PushArgument)                              \
   V(Random)                                    \
   V(RegExpLiteral)                             \
@@ skipping 1832 matching lines @@
           return Representation::Double();
         case kMathAbs:
           return representation();
         default:
           UNREACHABLE();
           return Representation::None();
       }
     }
   }
 
-  virtual HValue* Canonicalize();
+  virtual HValue* Canonicalize() {
+    // If the input is integer32 then we replace the floor instruction
+    // with its inputs.  This happens before the representation changes are
+    // introduced.
+    if (op() == kMathFloor) {
+      if (value()->representation().IsInteger32()) return value();
+    }
+    return this;
+  }
 
   BuiltinFunctionId op() const { return op_; }
   const char* OpName() const;
 
   DECLARE_CONCRETE_INSTRUCTION(UnaryMathOperation)
 
  protected:
   virtual bool DataEquals(HValue* other) {
     HUnaryMathOperation* b = HUnaryMathOperation::cast(other);
     return op_ == b->op();
@@ skipping 737 matching lines @@
       SetFlag(kUseGVN);
     }
   }
 
   virtual HType CalculateInferredType();
 
   DECLARE_ABSTRACT_INSTRUCTION(BitwiseBinaryOperation)
 };
 
 
-class HMathFloorOfDiv: public HBinaryOperation {
- public:
-  HMathFloorOfDiv(HValue* context, HValue* left, HValue* right)
-      : HBinaryOperation(context, left, right) {
-    set_representation(Representation::Integer32());
-    SetFlag(kUseGVN);
-  }
-
-  virtual Representation RequiredInputRepresentation(int index) {
-    return Representation::Integer32();
-  }
-
-  DECLARE_CONCRETE_INSTRUCTION(MathFloorOfDiv)
-
- protected:
-  virtual bool DataEquals(HValue* other) { return true; }
-};
-
-
 class HArithmeticBinaryOperation: public HBinaryOperation {
  public:
   HArithmeticBinaryOperation(HValue* context, HValue* left, HValue* right)
       : HBinaryOperation(context, left, right) {
     set_representation(Representation::Tagged());
     SetFlag(kFlexibleRepresentation);
     SetAllSideEffects();
   }
 
   virtual void RepresentationChanged(Representation to) {
@@ skipping 2176 matching lines @@
   DECLARE_CONCRETE_INSTRUCTION(LoadFieldByIndex);
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_