Support symbol comparison in crankshaft.

src/hydrogen-instructions.h

Index: src/hydrogen-instructions.h
diff --git a/src/hydrogen-instructions.h b/src/hydrogen-instructions.h
index 85a06fcbb7b56a87a9fec6b574ea21e98273a8f2..025a2fa77c94966e3f36a2322e94e07e589501ad 100644
--- a/src/hydrogen-instructions.h
+++ b/src/hydrogen-instructions.h
@@ -91,6 +91,7 @@ class LChunkBuilder;
   V(Compare)                                   \
   V(CompareJSObjectEq)                         \
   V(CompareMap)                                \
+  V(CompareSymbolEq)                           \
   V(Constant)                                  \
   V(Context)                                   \
   V(DeleteProperty)                            \
@@ -2409,6 +2410,38 @@ class HCompareJSObjectEq: public HBinaryOperation {
 };
 
 
+class HCompareSymbolEq: public HBinaryOperation {
+ public:
+  HCompareSymbolEq(HValue* left, HValue* right, Token::Value op)
+      : HBinaryOperation(left, right), op_(op) {
+    ASSERT(op == Token::EQ || op == Token::EQ_STRICT);
+    set_representation(Representation::Tagged());
+    SetFlag(kUseGVN);
+    SetFlag(kDependsOnMaps);
+  }
+
+  Token::Value op() const { return op_; }
+
+  virtual bool EmitAtUses() {
+    return !HasSideEffects() && !HasMultipleUses();
+  }
+
+  virtual Representation RequiredInputRepresentation(int index) const {
+    return Representation::Tagged();
+  }
+
+  virtual HType CalculateInferredType() { return HType::Boolean(); }
+
+  DECLARE_CONCRETE_INSTRUCTION(CompareSymbolEq);
+
+ protected:
+  virtual bool DataEquals(HValue* other) { return true; }

[Mads Ager (chromium), 2011/05/11 12:37:31]

Don't you have to check that the ops are the same here? If the op is not used in
the check you should remove it from the instruction. If it is used you should
only GVN if the op is the same.

[Vitaly Repeshko, 2011/05/11 12:44:46]

Good catch! Fixed.

+
+ private:
+  const Token::Value op_;
+};
+
+
 class HUnaryPredicate: public HUnaryOperation {
  public:
   explicit HUnaryPredicate(HValue* value) : HUnaryOperation(value) {