Index: lib/Analysis/MemoryDependenceAnalysis.cpp
===================================================================
--- lib/Analysis/MemoryDependenceAnalysis.cpp
+++ lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -625,7 +625,7 @@
       // Atomic stores have complications involved.
       // A Monotonic store is OK if the query inst is itself not atomic.
       // FIXME: This is overly conservative.
-      if (!SI->isUnordered()) {
+      if (!SI->isUnordered() && SI->isAtomic()) {
         if (!QueryInst)
           return MemDepResult::getClobber(SI);
         if (SI->getOrdering() != Monotonic)
@@ -645,8 +645,15 @@
       // While volatile access cannot be eliminated, they do not have to clobber
       // non-aliasing locations, as normal accesses can for example be reordered
       // with volatile accesses.
-      if (SI->isVolatile())
-        return MemDepResult::getClobber(SI);
+      if (QueryInst && SI->isVolatile()) {
+        if (LoadInst *QLI = dyn_cast<LoadInst>(QueryInst)) {
+          if (!QLI->isSimple())
+            return MemDepResult::getClobber(SI);
+        } else if (StoreInst *QSI = dyn_cast<StoreInst>(QueryInst)) {
+          if (!QSI->isSimple())
+            return MemDepResult::getClobber(SI);
+        }
+      }
 
       // If alias analysis can tell that this store is guaranteed to not modify
       // the query pointer, ignore it.  Use getModRefInfo to handle cases where
Index: test/Transforms/GVN/volatile-nonvolatile.ll
===================================================================
--- /dev/null
+++ test/Transforms/GVN/volatile-nonvolatile.ll
@@ -0,0 +1,27 @@
+; RUN: opt -tbaa -gvn -S < %s | FileCheck %s
+; Check that we can eliminate the second load.
+; CHECK: load
+; CHECK-NOT: load
+
+%struct.t = type { i32* }
+
+define void @foo(%struct.t* nocapture readonly %p, i32 %v) #0 {
+entry:
+  %m = getelementptr inbounds %struct.t, %struct.t* %p, i32 0, i32 0
+  %0 = load i32*, i32** %m, align 4, !tbaa !1
+  store volatile i32 %v, i32* %0, align 4, !tbaa !6
+  %1 = load i32*, i32** %m, align 4, !tbaa !1
+  store volatile i32 %v, i32* %1, align 4, !tbaa !6
+  ret void
+}
+
+attributes #0 = { norecurse nounwind }
+
+!1 = !{!2, !3, i64 0}
+!2 = !{!"", !3, i64 0}
+!3 = !{!"any pointer", !4, i64 0}
+!4 = !{!"omnipotent char", !5, i64 0}
+!5 = !{!"Simple C/C++ TBAA"}
+!6 = !{!7, !7, i64 0}
+!7 = !{!"int", !4, i64 0}
+