Remove redundant hydrogen- and lithium instruction for symbol comparison.

src/hydrogen.cc

Index: src/hydrogen.cc
===================================================================
--- src/hydrogen.cc	(revision 8347)
+++ src/hydrogen.cc	(working copy)
@@ -5237,15 +5237,13 @@
 }
 
 
-HCompareSymbolEq* HGraphBuilder::BuildSymbolCompare(HValue* left,
-                                                    HValue* right,
-                                                    Token::Value op) {
-  ASSERT(op == Token::EQ || op == Token::EQ_STRICT);
+HCompareObjectEq* HGraphBuilder::BuildSymbolCompare(HValue* left,
+                                                    HValue* right) {
   AddInstruction(new(zone()) HCheckNonSmi(left));
   AddInstruction(HCheckInstanceType::NewIsSymbol(left));
   AddInstruction(new(zone()) HCheckNonSmi(right));
   AddInstruction(HCheckInstanceType::NewIsSymbol(right));
-  return new(zone()) HCompareSymbolEq(left, right, op);
+  return new(zone()) HCompareObjectEq(left, right);
 }
 
 
@@ -5594,7 +5592,7 @@
         AddInstruction(HCheckInstanceType::NewIsSpecObject(left));
         AddInstruction(new(zone()) HCheckNonSmi(right));
         AddInstruction(HCheckInstanceType::NewIsSpecObject(right));
-        instr = new(zone()) HCompareJSObjectEq(left, right);
+        instr = new(zone()) HCompareObjectEq(left, right);
         break;
       }
       default:
@@ -5603,7 +5601,7 @@
     }
   } else if (type_info.IsString() && oracle()->IsSymbolCompare(expr) &&
              (op == Token::EQ || op == Token::EQ_STRICT)) {
-    instr = BuildSymbolCompare(left, right, op);

[William Hesse, 2011/06/21 10:41:19]

Why is this factored out into a separate function, and the exact same four
lines, ten lines above, is not factored out?
Could these share code, except for the CheckInstanceType?

+    instr = BuildSymbolCompare(left, right);
   } else {
     HCompare* compare = new(zone()) HCompare(left, right, op);
     Representation r = ToRepresentation(type_info);
@@ -5849,7 +5847,7 @@
   CHECK_ALIVE(VisitForValue(call->arguments()->at(1)));
   HValue* right = Pop();
   HValue* left = Pop();
-  HCompareJSObjectEq* result = new(zone()) HCompareJSObjectEq(left, right);
+  HCompareObjectEq* result = new(zone()) HCompareObjectEq(left, right);
   ast_context()->ReturnInstruction(result, call->id());
 }