Clean up handling of global cell stores in the optimizing compiler.

src/x64/lithium-x64.cc

Index: src/x64/lithium-x64.cc
diff --git a/src/x64/lithium-x64.cc b/src/x64/lithium-x64.cc
index 7fa8a3999c91f797c05b4b7778d283f931f099dd..ac4d5f5d3e6ffae92863dc35d3877a663cfd1585 100644
--- a/src/x64/lithium-x64.cc
+++ b/src/x64/lithium-x64.cc
@@ -1768,11 +1768,12 @@ LInstruction* LChunkBuilder::DoLoadGlobalGeneric(HLoadGlobalGeneric* instr) {
 
 
 LInstruction* LChunkBuilder::DoStoreGlobalCell(HStoreGlobalCell* instr) {
-  LStoreGlobalCell* result =
-      new LStoreGlobalCell(UseTempRegister(instr->value()),
-                           TempRegister(),
-                           TempRegister());
-  return instr->RequiresHoleCheck() ? AssignEnvironment(result) : result;
+  LOperand* value = UseRegister(instr->value());
+  // Use a temp to avoid reloading the cell value address in the case where
+  // we perform a hole check.
+  return instr->RequiresHoleCheck()
+      ? AssignEnvironment(new LStoreGlobalCell(value, TempRegister()))
+      : new LStoreGlobalCell(value, NULL);
 }