[PATCH] [BasicAA] Make better use of zext and sign information.

[hfinkel at anl.gov]

================
Comment at: lib/Analysis/BasicAliasAnalysis.cpp:1069
@@ +1068,3 @@
+      if (!isValueEqualInPotentialCycles(V, V))
+        return PartialAlias;
+
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If I change this PartialAlias return to MayAlias, all of the regression tests still pass. Is there a test covering this?

http://reviews.llvm.org/D5866