Delete dead code from HOptimizedGraphBuilder::VisitCompareOperation

src/hydrogen.cc

Index: src/hydrogen.cc
diff --git a/src/hydrogen.cc b/src/hydrogen.cc
index c25d7a12d1c25707bd54bbd6f2e40afaa237dca6..38ed57503aa6f07292186700b5a3e4abeee741fd 100644
--- a/src/hydrogen.cc
+++ b/src/hydrogen.cc
@@ -8339,24 +8339,6 @@ void HOptimizedGraphBuilder::VisitCompareOperation(CompareOperation* expr) {
         New<HStringCompareAndBranch>(left, right, op);
     result->set_position(expr->position());
     return ast_context()->ReturnControl(result, expr->id());
-  } else if (combined_type->NumClasses() == 1 && Token::IsEqualityOp(op)) {

[rossberg, 2013/10/15 10:49:18]

This case isn't actually entirely dead, since it would be taken if combined_type
was e.g. String \/ Class(m). OTOH, it would also do the wrong thing in that
case... 8-{

-    BuildCheckHeapObject(left);
-    BuildCheckMap(left, combined_type->Classes().Current());
-    BuildCheckHeapObject(right);
-    BuildCheckMap(right, combined_type->Classes().Current());
-    HCompareObjectEqAndBranch* result =
-        New<HCompareObjectEqAndBranch>(left, right);
-    result->set_position(expr->position());
-    return ast_context()->ReturnInstruction(result, expr->id());
-  } else if (combined_type->Is(Type::Receiver()) && Token::IsEqualityOp(op)) {
-    BuildCheckHeapObject(left);
-    AddInstruction(HCheckInstanceType::NewIsSpecObject(left, zone()));
-    BuildCheckHeapObject(right);
-    AddInstruction(HCheckInstanceType::NewIsSpecObject(right, zone()));
-    HCompareObjectEqAndBranch* result =
-        New<HCompareObjectEqAndBranch>(left, right);
-    result->set_position(expr->position());
-    return ast_context()->ReturnInstruction(result, expr->id());
   } else {
     if (combined_rep.IsTagged() || combined_rep.IsNone()) {
       HCompareGeneric* result =