Eliminate intentional conversion from Smi to Int32 in HMul

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 784 matching lines @@
   // Mark this HValue as dead and to be removed from other HValues' use lists.
   void Kill();
 
   int flags() const { return flags_; }
   void SetFlag(Flag f) { flags_ |= (1 << f); }
   void ClearFlag(Flag f) { flags_ &= ~(1 << f); }
   bool CheckFlag(Flag f) const { return (flags_ & (1 << f)) != 0; }
 
   // Returns true if the flag specified is set for all uses, false otherwise.
   bool CheckUsesForFlag(Flag f);
+  // Same as before and the first one without the flag is returned in value.
+  bool CheckUsesForFlag(Flag f, HValue** value);
   // Returns true if the flag specified is set for all uses, and this set
   // of uses is non-empty.
   bool HasAtLeastOneUseWithFlagAndNoneWithout(Flag f);
 
   GVNFlagSet gvn_flags() const { return gvn_flags_; }
   void SetGVNFlag(GVNFlag f) { gvn_flags_.Add(f); }
   void ClearGVNFlag(GVNFlag f) { gvn_flags_.Remove(f); }
   bool CheckGVNFlag(GVNFlag f) const { return gvn_flags_.Contains(f); }
   void SetAllSideEffects() { gvn_flags_.Add(AllSideEffectsFlagSet()); }
   void ClearAllSideEffects() {
@@ skipping 708 matching lines @@
           bool is_truncating_to_smi,
           bool is_truncating_to_int32,
           bool allow_undefined_as_nan)
       : HUnaryOperation(value) {
     ASSERT(!value->representation().IsNone());
     ASSERT(!to.IsNone());
     ASSERT(!value->representation().Equals(to));
     set_representation(to);
     SetFlag(kUseGVN);
     if (allow_undefined_as_nan) SetFlag(kAllowUndefinedAsNaN);
-    if (is_truncating_to_smi) SetFlag(kTruncatingToSmi);
+    if (is_truncating_to_smi) {
+      SetFlag(kTruncatingToSmi);
+      SetFlag(kTruncatingToInt32);
+    }
     if (is_truncating_to_int32) SetFlag(kTruncatingToInt32);
     if (value->representation().IsSmi() || value->type().IsSmi()) {
       set_type(HType::Smi());
     } else {
       set_type(HType::TaggedNumber());
       if (to.IsTagged()) SetGVNFlag(kChangesNewSpacePromotion);
     }
   }
 
   virtual HValue* EnsureAndPropagateNotMinusZero(BitVector* visited);
@@ skipping 2883 matching lines @@
   virtual HValue* Canonicalize();
 
   // Only commutative if it is certain that not two objects are multiplicated.
   virtual bool IsCommutative() const {
     return !representation().IsTagged();
   }
 
   virtual void UpdateRepresentation(Representation new_rep,
                                     HInferRepresentationPhase* h_infer,
                                     const char* reason) {
-    if (new_rep.IsSmi()) new_rep = Representation::Integer32();
     HArithmeticBinaryOperation::UpdateRepresentation(new_rep, h_infer, reason);
   }
 
   DECLARE_CONCRETE_INSTRUCTION(Mul)
 
  protected:
   virtual bool DataEquals(HValue* other) { return true; }
 
   virtual Range* InferRange(Zone* zone);
 
@@ skipping 191 matching lines @@
     // BIT_AND with a smi-range positive value will always unset the
     // entire sign-extension of the smi-sign.
     if (op == Token::BIT_AND &&
         ((left->IsConstant() &&
           left->representation().IsSmi() &&
           HConstant::cast(left)->Integer32Value() >= 0) ||
          (right->IsConstant() &&
           right->representation().IsSmi() &&
           HConstant::cast(right)->Integer32Value() >= 0))) {
       SetFlag(kTruncatingToSmi);
+      SetFlag(kTruncatingToInt32);
     // BIT_OR with a smi-range negative value will always set the entire
     // sign-extension of the smi-sign.
     } else if (op == Token::BIT_OR &&
         ((left->IsConstant() &&
           left->representation().IsSmi() &&
           HConstant::cast(left)->Integer32Value() < 0) ||
          (right->IsConstant() &&
           right->representation().IsSmi() &&
           HConstant::cast(right)->Integer32Value() < 0))) {
       SetFlag(kTruncatingToSmi);
+      SetFlag(kTruncatingToInt32);
     }
   }
 
   Token::Value op_;
 };
 
 
 class HShl: public HBitwiseBinaryOperation {
  public:
   static HInstruction* New(Zone* zone,
@@ skipping 2096 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_