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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@90002 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/MemoryDependenceAnalysis.cpp b/lib/Analysis/MemoryDependenceAnalysis.cpp
index 0aacd16..f958e75 100644
--- a/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -1004,8 +1004,12 @@
Value *PredPtr = PHITranslatePointer(PtrInst, BB, Pred, TD);
// If PHI translation fails, bail out.
- if (PredPtr == 0)
+ if (PredPtr == 0) {
+ // FIXME: Instead of modelling this as a phi trans failure, we should
+ // model this as a clobber in the one predecessor. This will allow
+ // us to PRE values that are only available in some preds but not all.
goto PredTranslationFailure;
+ }
// Check to see if we have already visited this pred block with another
// pointer. If so, we can't do this lookup. This failure can occur