[PATCH] Further relax the constraint on atomics in MemoryDependencyAnalysis.cpp

[JF Bastien]

The change looks good overall, but I'd like to have @reames review it too.

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Comment at: test/Transforms/DeadStoreElimination/atomic.ll:163
@@ +162,3 @@
+  store atomic i32 0, i32* @y release, align 4
+  %x = load atomic i32* @y acquire, align 4
+  store i32 1, i32* @x
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Why not also test load-acq followed by store-rel here and in other places (or the reverse store/load)? It seems like a good sanity check.

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Comment at: test/Transforms/GVN/atomic.ll:133
@@ -106,1 +132,2 @@
 
+
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Drop the extra space.

http://reviews.llvm.org/D4845