Improve smi support in crankshaft

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 867 matching lines @@
     ASSERT(CheckFlag(kFlexibleRepresentation));
     RepresentationChanged(r);
     representation_ = r;
     if (r.IsTagged()) {
       // Tagged is the bottom of the lattice, don't go any further.
       ClearFlag(kFlexibleRepresentation);
     }
   }
   virtual void AssumeRepresentation(Representation r);
 
-  virtual bool IsConvertibleToInteger() const { return true; }
+  virtual Representation KnownOptimalRepresentation() {
+    Representation r = representation();
+    if (r.IsTagged()) {
+      HType t = type();
+      if (t.IsSmi()) return Representation::Smi();
+      if (t.IsHeapNumber()) return Representation::Double();
+      if (t.IsHeapObject()) return r;
+      return Representation::None();
+    }
+    return r;
+  }
 
   HType type() const { return type_; }
   void set_type(HType new_type) {
     ASSERT(new_type.IsSubtypeOf(type_));
     type_ = new_type;
   }
 
   // An operation needs to override this function iff:
   //   1) it can produce an int32 output.
   //   2) the true value of its output can potentially be minus zero.
@@ skipping 1543 matching lines @@
 
  private:
   virtual bool IsDeletable() const { return true; }
 };
 
 
 class HMapEnumLength: public HUnaryOperation {
  public:
   explicit HMapEnumLength(HValue* value) : HUnaryOperation(value) {
     set_type(HType::Smi());
-    set_representation(Representation::Tagged());
+    set_representation(Representation::Smi());
     SetFlag(kUseGVN);
     SetGVNFlag(kDependsOnMaps);
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::Tagged();
   }
 
   DECLARE_CONCRETE_INSTRUCTION(MapEnumLength)
 
@@ skipping 470 matching lines @@
   UniqueValueId first_prototype_unique_id_;
   UniqueValueId last_prototype_unique_id_;
 };
 
 
 class HPhi: public HValue {
  public:
   HPhi(int merged_index, Zone* zone)
       : inputs_(2, zone),
         merged_index_(merged_index),
-        phi_id_(-1),
-        is_convertible_to_integer_(true) {
+        phi_id_(-1) {
     for (int i = 0; i < Representation::kNumRepresentations; i++) {
       non_phi_uses_[i] = 0;
       indirect_uses_[i] = 0;
     }
     ASSERT(merged_index >= 0);
     SetFlag(kFlexibleRepresentation);
     SetFlag(kAllowUndefinedAsNaN);
   }
 
   virtual Representation RepresentationFromInputs();
 
   virtual Range* InferRange(Zone* zone);
   virtual void InferRepresentation(HInferRepresentation* h_infer);
   Representation RepresentationFromUseRequirements();
   virtual Representation RequiredInputRepresentation(int index) {
     return representation();
   }
+  virtual Representation KnownOptimalRepresentation() {
+    return representation();
+  }
   virtual HType CalculateInferredType();
   virtual int OperandCount() { return inputs_.length(); }
   virtual HValue* OperandAt(int index) const { return inputs_[index]; }
   HValue* GetRedundantReplacement();
   void AddInput(HValue* value);
   bool HasRealUses();
 
   bool IsReceiver() const { return merged_index_ == 0; }
 
   int merged_index() const { return merged_index_; }
@@ skipping 35 matching lines @@
     return indirect_uses_[Representation::kDouble];
   }
   int phi_id() { return phi_id_; }
 
   static HPhi* cast(HValue* value) {
     ASSERT(value->IsPhi());
     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;
-  }
-
-  bool AllOperandsConvertibleToInteger() {
-    for (int i = 0; i < OperandCount(); ++i) {
-      if (!OperandAt(i)->IsConvertibleToInteger()) {
-        if (FLAG_trace_representation) {
-          HValue* input = OperandAt(i);
-          PrintF("#%d %s: Input #%d %s at %d is NCTI\n",
-                 id(), Mnemonic(), input->id(), input->Mnemonic(), i);
-        }
-        return false;
-      }
-    }
-    return true;
-  }
-
   void SimplifyConstantInputs();
 
   // TODO(titzer): we can't eliminate the receiver for generating backtraces
   virtual bool IsDeletable() const { return !IsReceiver(); }
 
  protected:
   virtual void DeleteFromGraph();
   virtual void InternalSetOperandAt(int index, HValue* value) {
     inputs_[index] = value;
   }
 
   virtual bool IsRelationTrueInternal(NumericRelation relation,
                                       HValue* other,
                                       int offset = 0,
                                       int scale = 0);
 
  private:
   ZoneList<HValue*> inputs_;
   int merged_index_;
 
   int non_phi_uses_[Representation::kNumRepresentations];
   int indirect_uses_[Representation::kNumRepresentations];
   int phi_id_;
-  bool is_convertible_to_integer_;
 };
 
 
 class HInductionVariableAnnotation : public HUnaryOperation {
  public:
   static HInductionVariableAnnotation* AddToGraph(HPhi* phi,
                                                   NumericRelation relation,
                                                   int operand_index);
 
   NumericRelation relation() { return relation_; }
@@ skipping 116 matching lines @@
            unique_id_ == UniqueValueId(heap->true_value()) ||
            unique_id_ == UniqueValueId(heap->false_value()) ||
            unique_id_ == UniqueValueId(heap->the_hole_value()) ||
            unique_id_ == UniqueValueId(heap->empty_string());
   }
 
   virtual Representation RequiredInputRepresentation(int index) {
     return Representation::None();
   }
 
-  virtual bool IsConvertibleToInteger() const {
-    return has_int32_value_;
+  virtual Representation KnownOptimalRepresentation() {
+    if (HasSmiValue()) return Representation::Smi();
+    if (HasInteger32Value()) return Representation::Integer32();
+    if (HasNumberValue()) return Representation::Double();
+    return Representation::Tagged();
   }
 
   virtual bool EmitAtUses() { return !representation().IsDouble(); }
   virtual void PrintDataTo(StringStream* stream);
   virtual HType CalculateInferredType();
   bool IsInteger() { return handle()->IsSmi(); }
   HConstant* CopyToRepresentation(Representation r, Zone* zone) const;
   HConstant* CopyToTruncatedInt32(Zone* zone) const;
   bool HasInteger32Value() const { return has_int32_value_; }
   int32_t Integer32Value() const {
     ASSERT(HasInteger32Value());
     return int32_value_;
   }
-  bool HasSmiValue() const {
-    return has_smi_value_;
-  }
+  bool HasSmiValue() const { return has_smi_value_; }
   bool HasDoubleValue() const { return has_double_value_; }
   double DoubleValue() const {
     ASSERT(HasDoubleValue());
     return double_value_;
   }
   bool IsTheHole() const {
     if (HasDoubleValue() && FixedDoubleArray::is_the_hole_nan(double_value_)) {
       return true;
     }
     Heap* heap = isolate()->heap();
@@ skipping 1482 matching lines @@
   }
 
   void set_incoming_value(HPhi* value) {
     incoming_value_ = value;
   }
 
   HPhi* incoming_value() {
     return incoming_value_;
   }
 
+  virtual Representation KnownOptimalRepresentation() {
+    if (incoming_value_ == NULL) return Representation::None();
+    return incoming_value_->KnownOptimalRepresentation();
+  }
+
   DECLARE_CONCRETE_INSTRUCTION(UnknownOSRValue)
 
  private:
   HPhi* incoming_value_;
 };
 
 
 class HLoadGlobalCell: public HTemplateInstruction<0> {
  public:
   HLoadGlobalCell(Handle<JSGlobalPropertyCell> cell, PropertyDetails details)
@@ skipping 1771 matching lines @@
   virtual bool IsDeletable() const { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_