Don't MISS if you read the hole from certain FastHoley arrays.

src/arm64/lithium-arm64.cc

Index: src/arm64/lithium-arm64.cc
diff --git a/src/arm64/lithium-arm64.cc b/src/arm64/lithium-arm64.cc
index c57cb689a042cf8ea9e717bbeb26a3d08db7c9c4..1fb3e5096e8a86e926d875b0ce02e6f083e9ca92 100644
--- a/src/arm64/lithium-arm64.cc
+++ b/src/arm64/lithium-arm64.cc
@@ -1724,9 +1724,11 @@ LInstruction* LChunkBuilder::DoLoadKeyed(HLoadKeyed* instr) {
       LOperand* temp = instr->key()->IsConstant() ? NULL : TempRegister();
       LLoadKeyedFixed* result =
           new(zone()) LLoadKeyedFixed(elements, key, temp);
-      return instr->RequiresHoleCheck()
-          ? AssignEnvironment(DefineAsRegister(result))
-          : DefineAsRegister(result);
+      return (instr->RequiresHoleCheck() ||

[Jakob Kummerow, 2015/04/23 13:40:00]

Suggestion: I'd model this after the case below (lines 1740 ff.):

      LInstruction* result =
          DefineAsRegister(new(zone()) LLoadKeyedFixed(elements, key, temp));
      if (instr->RequiresHoleCheck() ||
          (instr->hole_mode == ... && info()->IsStub()) {
        result = AssignEnvironment(result);
      }
      return result;

[mvstanton, 2015/04/27 07:57:12]

Done, and I made the double case above follow the same protocol...looks nicer.

+              (instr->hole_mode() == CONVERT_HOLE_TO_UNDEFINED &&
+               info()->IsStub()))
+                 ? AssignEnvironment(DefineAsRegister(result))
+                 : DefineAsRegister(result);
     }
   } else {
     DCHECK((instr->representation().IsInteger32() &&