fix a bug handling 'not x' when x is undef.

llvm-svn: 88864
2009-11-15 19:57:43 +00:00 · 2009-11-15 19:57:43 +00:00 · 5f037b6439
parent fb7613a5d6
commit 5f037b6439
1 changed files with 3 additions and 2 deletions
--- a/llvm/lib/Transforms/Scalar/JumpThreading.cpp
+++ b/llvm/lib/Transforms/Scalar/JumpThreading.cpp
@ -350,8 +350,9 @@ ComputeValueKnownInPredecessors(Value *V, BasicBlock *BB,PredValueInfo &Result){

      // Invert the known values.
      for (unsigned i = 0, e = Result.size(); i != e; ++i)
-        Result[i].first =
-          cast<ConstantInt>(ConstantExpr::getNot(Result[i].first));
+        if (Result[i].first)
+          Result[i].first =
+            cast<ConstantInt>(ConstantExpr::getNot(Result[i].first));
      return true;
    }
  }