Tweak the Better{Left,Right}Operand() heuristic

src/hydrogen-instructions.cc

 // 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 4012 matching lines @@
     if (!use_rep.IsNone() &&
         !use_rep.IsSmi() &&
         !use_rep.IsTagged()) {
       return true;
     }
   }
   return false;
 }
 
 
+bool HValue::UsedBy(HValue* value) {
+  for (HUseIterator it(uses()); !it.Done(); it.Advance()) {
+    if (it.value() == value) return true;
+  }
+  return false;
+}
+
+
 // Node-specific verification code is only included in debug mode.
 #ifdef DEBUG
 
 void HPhi::Verify() {
   ASSERT(OperandCount() == block()->predecessors()->length());
   for (int i = 0; i < OperandCount(); ++i) {
     HValue* value = OperandAt(i);
     HBasicBlock* defining_block = value->block();
     HBasicBlock* predecessor_block = block()->predecessors()->at(i);
     ASSERT(defining_block == predecessor_block ||
@@ skipping 186 matching lines @@
       break;
     case kExternalMemory:
       stream->Add("[external-memory]");
       break;
   }
 
   stream->Add("@%d", offset());
 }
 
 } }  // namespace v8::internal