From: yeom <yeom>
Date: Sat, 13 Nov 2010 04:07:38 +0000 (+0000)
Subject: removes unnecessary LOCKXCHG operation to optimize.
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=e600b4eb22e7d27d5211c427d39d39ef5eeae8a0;p=IRC.git

removes unnecessary LOCKXCHG operation to optimize.
---

diff --git a/Robust/src/Runtime/squeue.h b/Robust/src/Runtime/squeue.h
index ec30fd74..b67f3b92 100644
--- a/Robust/src/Runtime/squeue.h
+++ b/Robust/src/Runtime/squeue.h
@@ -148,7 +148,8 @@ static inline void* dqPopTop(deque *p) {
     return item;
   } else {
     void * item=NULL;
-    item=(void *) LOCKXCHG((unsigned INTPTR*) &(realptr->work), (unsigned INTPTR) item);
+    if (realptr->work!=NULL)
+      item=(void *) LOCKXCHG((unsigned INTPTR*) &(realptr->work), (unsigned INTPTR) item);
     return item;
   }
 }