[polly] r314116 - [ScopInfo] Allow uniform branch conditions

[Michael Kruse via llvm-commits]

2017-09-25 18:37 GMT+02:00 Tobias Grosser via llvm-commits
<llvm-commits at lists.llvm.org>:
> +  if (auto *PHI = dyn_cast<PHINode>(Condition)) {
> +    auto *Unique = dyn_cast<ConstantInt>(
> +        getUniqueNonErrorValue(PHI, &S.getRegion(), *S.getLI(), *S.getDT()));
> +
> +    if (Unique->isZero())

If getUniqueNonErrorValue returns something else than a ConstantInt,
dyn_cast<ConstantInt> returns nullptr and the line above trigger
indefined behaviour.
If getUniqueNonErrorValue always returns ConstantInt in this use case,
we should use cast<ConstantInt> instead.
If it may return something else, we need to handle that case. Is it:

if (Unique && Unique->isZero())

what you intended?

Michael