Revert r11420 because Win32 compilation was broken.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
===================================================================
--- src/hydrogen-instructions.h	(revision 11420)
+++ src/hydrogen-instructions.h	(working copy)
@@ -140,7 +140,6 @@
   V(LoadNamedField)                            \
   V(LoadNamedFieldPolymorphic)                 \
   V(LoadNamedGeneric)                          \
-  V(MathFloorOfDiv)                            \
   V(Mod)                                       \
   V(Mul)                                       \
   V(ObjectLiteral)                             \
@@ -1993,7 +1992,15 @@
     }
   }
 
-  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;
@@ -2751,25 +2758,6 @@
 };
 
 
-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)