Disable the asserts that check that normalization is perfectly
invertible. ScalarEvolution's folding routines don't always succeed
in canonicalizing equal expressions to a single canonical form, and
this can cause these asserts to fail, even though there's no actual
correctness problem. This fixes PR8066.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113021 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolutionNormalization.cpp b/lib/Analysis/ScalarEvolutionNormalization.cpp
index 498387a..ac36cef 100644
--- a/lib/Analysis/ScalarEvolutionNormalization.cpp
+++ b/lib/Analysis/ScalarEvolutionNormalization.cpp
@@ -108,7 +108,11 @@
Result = SE.getMinusSCEV(Result, TransformedStep);
Loops.insert(L);
}
-#ifdef XDEBUG
+#if 0
+ // This assert is conceptually correct, but ScalarEvolution currently
+ // sometimes fails to canonicalize two equal SCEVs to exactly the same
+ // form. It's possibly a pessimization when this happens, but it isn't a
+ // correctness problem, so disable this assert for now.
assert(S == TransformForPostIncUse(Denormalize, Result,
User, OperandValToReplace,
Loops, SE, DT) &&
@@ -122,7 +126,8 @@
User, OperandValToReplace, Loops, SE, DT);
Result = SE.getMinusSCEV(Result, TransformedStep);
}
-#ifdef XDEBUG
+#if 0
+ // See the comment on the assert above.
assert(S == TransformForPostIncUse(Denormalize, Result,
User, OperandValToReplace,
Loops, SE, DT) &&