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llvm-svn: 90002
2009-11-27 08:40:14 +00:00 · 2009-11-27 08:40:14 +00:00 · 6d294de548
parent ac323297e0
commit 6d294de548
1 changed files with 5 additions and 1 deletions
--- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
@ -1004,8 +1004,12 @@ getNonLocalPointerDepFromBB(Value *Pointer, uint64_t PointeeSize,
      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