Hydrogen binop improvements

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 3863 matching lines @@
 
 class HBitwiseBinaryOperation : public HBinaryOperation {
  public:
   HBitwiseBinaryOperation(HValue* context, HValue* left, HValue* right,
                           HType type = HType::Tagged())
       : HBinaryOperation(context, left, right, type) {
     SetFlag(kFlexibleRepresentation);
     SetFlag(kTruncatingToInt32);
     SetFlag(kAllowUndefinedAsNaN);
     SetAllSideEffects();
+    if (left->IsForceRepresentation()) {

[Sven Panne, 2013/09/16 13:38:09]

Why do we propagate back only to HForceRepresentation? This looks weird...

[oliv, 2013/09/16 15:44:43]

It is actually even wrong in the general case, sorry

+      left->SetFlag(kTruncatingToInt32);
+    }
+    if (right->IsForceRepresentation()) {
+      right->SetFlag(kTruncatingToInt32);
+    }
   }
 
   virtual void RepresentationChanged(Representation to) V8_OVERRIDE {
-    if (!to.IsTagged()) {
-      ASSERT(to.IsSmiOrInteger32());
+    if (to.IsTagged()) {
+      SetAllSideEffects();
+      ClearFlag(kUseGVN);
+    } else {
       ClearAllSideEffects();
       SetFlag(kUseGVN);
-    } else {
-      SetAllSideEffects();
-      ClearFlag(kUseGVN);
     }
   }
 
   virtual void UpdateRepresentation(Representation new_rep,
                                     HInferRepresentationPhase* h_infer,
                                     const char* reason) V8_OVERRIDE {
     // We only generate either int32 or generic tagged bitwise operations.
     if (new_rep.IsDouble()) new_rep = Representation::Integer32();
     HBinaryOperation::UpdateRepresentation(new_rep, h_infer, reason);
   }
@@ skipping 613 matching lines @@
 
 
 class HMul V8_FINAL : public HArithmeticBinaryOperation {
  public:
   static HInstruction* New(Zone* zone,
                            HValue* context,
                            HValue* left,
                            HValue* right);
 
   static HInstruction* NewImul(Zone* zone,
-                               HValue* context,
-                               HValue* left,
-                               HValue* right) {
-    HMul* mul = new(zone) HMul(context, left, right);
+                         HValue* context,
+                         HValue* left,
+                         HValue* right) {
+    HInstruction* instr = HMul::New(zone, context, left, right);
+    if (!instr->IsMul()) return instr;
+    HMul* mul = HMul::cast(instr);
     // TODO(mstarzinger): Prevent bailout on minus zero for imul.
     mul->AssumeRepresentation(Representation::Integer32());
     mul->ClearFlag(HValue::kCanOverflow);
     return mul;
   }
 
   virtual HValue* EnsureAndPropagateNotMinusZero(
       BitVector* visited) V8_OVERRIDE;
 
   virtual HValue* Canonicalize() V8_OVERRIDE;
@@ skipping 1946 matching lines @@
 
   DECLARE_CONCRETE_INSTRUCTION(StringAdd)
 
  protected:
   virtual bool DataEquals(HValue* other) V8_OVERRIDE { return true; }
 
  private:
   HStringAdd(HValue* context, HValue* left, HValue* right, StringAddFlags flags)
       : HBinaryOperation(context, left, right, HType::String()), flags_(flags) {
     set_representation(Representation::Tagged());
-    SetFlag(kUseGVN);
-    SetGVNFlag(kDependsOnMaps);
-    SetGVNFlag(kChangesNewSpacePromotion);
+    if (flags_ == STRING_ADD_CHECK_NONE) {
+      SetFlag(kUseGVN);
+      SetGVNFlag(kDependsOnMaps);
+      SetGVNFlag(kChangesNewSpacePromotion);
+    } else {
+      SetAllSideEffects();
+    }
   }
 
   // No side-effects except possible allocation.
   // NOTE: this instruction _does not_ call ToString() on its inputs.
-  virtual bool IsDeletable() const V8_OVERRIDE { return true; }
+  virtual bool IsDeletable() const V8_OVERRIDE {
+    return flags_ == STRING_ADD_CHECK_NONE;
+  }
 
   const StringAddFlags flags_;
 };
 
 
 class HStringCharCodeAt V8_FINAL : public HTemplateInstruction<3> {
  public:
   static HStringCharCodeAt* New(Zone* zone,
                                 HValue* context,
                                 HValue* string,
@@ skipping 456 matching lines @@
   virtual bool IsDeletable() const V8_OVERRIDE { return true; }
 };
 
 
 #undef DECLARE_INSTRUCTION
 #undef DECLARE_CONCRETE_INSTRUCTION
 
 } }  // namespace v8::internal
 
 #endif  // V8_HYDROGEN_INSTRUCTIONS_H_