[llvm-commits] [llvm] r90002 - /llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp

[Chris Lattner]

Author: lattner
Date: Fri Nov 27 02:40:14 2009
New Revision: 90002

URL: http://llvm.org/viewvc/llvm-project?rev=90002&view=rev
Log:
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Modified:
    llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp

Modified: llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp?rev=90002&r1=90001&r2=90002&view=diff

==============================================================================
--- llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/MemoryDependenceAnalysis.cpp Fri Nov 27 02:40:14 2009
@@ -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