SCEV validator: Ignore CouldNotCompute/undef on both sides. This is mostly noise and blocks finding more severe bugs.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@166873 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 806eafa..a6723c3 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -7005,15 +7005,18 @@
// Compare the stringified SCEVs. We don't care if undef backedgetaken count
// changes.
- // FIXME: We currently ignore SCEV changes towards CouldNotCompute. This
+ // FIXME: We currently ignore SCEV changes from/to CouldNotCompute. This
// means that a pass is buggy or SCEV has to learn a new pattern but is
// usually not harmful.
if (OldI->second != NewI->second &&
OldI->second.find("undef") == std::string::npos &&
+ NewI->second.find("undef") == std::string::npos &&
+ OldI->second != "***COULDNOTCOMPUTE***" &&
NewI->second != "***COULDNOTCOMPUTE***") {
- dbgs() << "SCEVValidator: SCEV for Loop '"
+ dbgs() << "SCEVValidator: SCEV for loop '"
<< OldI->first->getHeader()->getName()
- << "' from '" << OldI->second << "' to '" << NewI->second << "'!";
+ << "' changed from '" << OldI->second
+ << "' to '" << NewI->second << "'!\n";
std::abort();
}
}