Tweak HConstant::EmitAtUses() to eliminate useless constant generation

src/hydrogen-instructions.cc

Index: src/hydrogen-instructions.cc
diff --git a/src/hydrogen-instructions.cc b/src/hydrogen-instructions.cc
index cca95b9b5f233198a59486586132dcf3c6d94606..3c4482547a2af701f56c740e047a4d8e287d7105 100644
--- a/src/hydrogen-instructions.cc
+++ b/src/hydrogen-instructions.cc
@@ -2526,9 +2526,11 @@ void HConstant::Initialize(Representation r) {
 
 bool HConstant::EmitAtUses() {
   ASSERT(IsLinked());
-  if (block()->graph()->has_osr()) {
-    return block()->graph()->IsStandardConstant(this);
+  if (block()->graph()->has_osr() &&
+      block()->graph()->IsStandardConstant(this)) {
+    return true;
   }
+  if (UseCount() == 0) return true;
   if (IsCell()) return false;
   if (representation().IsDouble()) return false;
   return true;