llvmorg-12.0.1-rc2-0-ge7dac564cd0e

1 files changed, 4 insertions, 0 deletions

diff --git a/llvm/lib/Analysis/ScalarEvolution.cpp b/llvm/lib/Analysis/ScalarEvolution.cpp
index fe9d8297d679..1a9ae68573e9 100644
--- a/llvm/lib/Analysis/ScalarEvolution.cpp
+++ b/llvm/lib/Analysis/ScalarEvolution.cpp
@@ -10622,6 +10622,10 @@ bool ScalarEvolution::isImpliedViaMerge(ICmpInst::Predicate Pred,
       if (!dominates(RHS, IncBB))
         return false;
       const SCEV *L = getSCEV(LPhi->getIncomingValueForBlock(IncBB));
+      // Make sure L does not refer to a value from a potentially previous
+      // iteration of a loop.
+      if (!properlyDominates(L, IncBB))
+        return false;
       if (!ProvedEasily(L, RHS))
         return false;
     }