Improve representation inference

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 702 matching lines @@
   void RemoveLastAddedRange();
   void ComputeInitialRange(Zone* zone);
 
   // Representation helpers.
   virtual Representation RequiredInputRepresentation(int index) = 0;
 
   virtual Representation InferredRepresentation() {
     return representation();
   }
 
+  // Type feedback access.
+  virtual Representation ObservedInputRepresentation(int index) {
+    return RequiredInputRepresentation(index);
+  }
+
   // This gives the instruction an opportunity to replace itself with an
   // instruction that does the same in some better way.  To replace an
   // instruction with a new one, first add the new instruction to the graph,
   // then return it.  Return NULL to have the instruction deleted.
   virtual HValue* Canonicalize() { return this; }
 
   bool Equals(HValue* other);
   virtual intptr_t Hashcode();
 
   // Printing support.
@@ skipping 1658 matching lines @@
     return reinterpret_cast<HPhi*>(value);
   }
   virtual Opcode opcode() const { return HValue::kPhi; }
 
   virtual bool IsConvertibleToInteger() const {
     return is_convertible_to_integer_;
   }
 
   void set_is_convertible_to_integer(bool b) {
     is_convertible_to_integer_ = b;
+    if (!is_convertible_to_integer_) {
+      non_phi_uses_[Representation::kInteger32] = 0;
+      indirect_uses_[Representation::kInteger32] = 0;
+    }
   }
 
   bool AllOperandsConvertibleToInteger() {
     for (int i = 0; i < OperandCount(); ++i) {
-      if (!OperandAt(i)->IsConvertibleToInteger()) return false;
+      if (!OperandAt(i)->IsConvertibleToInteger()) {
+        return false;
+      }
     }
     return true;
   }
 
  protected:
   virtual void DeleteFromGraph();
   virtual void InternalSetOperandAt(int index, HValue* value) {
     inputs_[index] = value;
   }
 
@@ skipping 133 matching lines @@
   HValue* context() { return OperandAt(0); }
   HValue* left() { return OperandAt(1); }
   HValue* right() { return OperandAt(2); }
 
   // TODO(kasperl): Move these helpers to the IA-32 Lithium
   // instruction sequence builder.
   HValue* LeastConstantOperand() {
     if (IsCommutative() && left()->IsConstant()) return right();
     return left();
   }
+
   HValue* MostConstantOperand() {
     if (IsCommutative() && left()->IsConstant()) return left();
     return right();
   }
 
   virtual bool IsCommutative() const { return false; }
 
   virtual void PrintDataTo(StringStream* stream);
 };
 
@@ skipping 145 matching lines @@
 };
 
 
 class HBitwiseBinaryOperation: public HBinaryOperation {
  public:
   HBitwiseBinaryOperation(HValue* context, HValue* left, HValue* right)
       : HBinaryOperation(context, left, right) {
     set_representation(Representation::Tagged());
     SetFlag(kFlexibleRepresentation);
     SetAllSideEffects();
+    observed_input_representation_[0] = Representation::Tagged();
+    observed_input_representation_[1] = Representation::None();
+    observed_input_representation_[2] = Representation::None();
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return index == 0
         ? Representation::Tagged()
         : representation();
   }
 
   virtual void RepresentationChanged(Representation to) {
     if (!to.IsTagged()) {
       ASSERT(to.IsInteger32());
       ClearAllSideEffects();
       SetFlag(kTruncatingToInt32);
       SetFlag(kUseGVN);
     }
   }
 
   virtual HType CalculateInferredType();
 
+  virtual Representation ObservedInputRepresentation(int index) {
+    return observed_input_representation_[index];
+  }
+
+  void InitializeObservedInputRepresentation(Representation r) {
+    observed_input_representation_[1] = r;
+    observed_input_representation_[2] = r;
+  }
+
   DECLARE_ABSTRACT_INSTRUCTION(BitwiseBinaryOperation)
+ private:
+  Representation observed_input_representation_[3];
 };
 
 
 class HMathFloorOfDiv: public HBinaryOperation {
  public:
   HMathFloorOfDiv(HValue* context, HValue* left, HValue* right)
       : HBinaryOperation(context, left, right) {
     set_representation(Representation::Integer32());
     SetFlag(kUseGVN);
   }
@@ skipping 2303 matching lines @@
   DECLARE_CONCRETE_INSTRUCTION(LoadFieldByIndex);
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_