When ScalarEvolution is told to forget the trip count for a loop, have

it also forget any SCEVs associated with loop-header PHIs in the loop,
as they may be dependent on trip count information.

llvm-svn: 70633

1 files changed, 5 insertions, 0 deletions

diff --git a/llvm/include/llvm/Analysis/ScalarEvolution.h b/llvm/include/llvm/Analysis/ScalarEvolution.h
index 6ef0b35e35d..a0a7c1e81d2 100644
--- a/llvm/include/llvm/Analysis/ScalarEvolution.h
+++ b/llvm/include/llvm/Analysis/ScalarEvolution.h
@@ -333,6 +333,11 @@ namespace llvm {
     /// expression cannot be evaluated, return UnknownValue itself.
     SCEVHandle getSCEVAtScope(SCEV *S, const Loop *L);
 
+    /// forgetLoopPHIs - Delete the memoized SCEVs associated with the
+    /// PHI nodes in the given loop. This is used when the trip count of
+    /// the loop may have changed.
+    void forgetLoopPHIs(const Loop *L);
+
   public:
     static char ID; // Pass identification, replacement for typeid
     ScalarEvolution();