[PATCH] D24680: Jump threading: avoid trying to split edge into landingpad block (PR27840)

[Hans Wennborg via llvm-commits]

hans added a comment.

In https://reviews.llvm.org/D24680#545412, @nlewycky wrote:

> I'm concerned that the fix is too narrow. There's 10 callers to llvm::SplitEdge in LLVM and haven't audited them so I don't know whether they also check whether they also do this check. It's certainly not in the comment on SplitEdge that it's allowed to assert if you pass it a landing pad block.


My thinking was that it seems what jump threading is trying to do with a "branch on xor" pattern isn't going to work with a landingpad anyway, and this would fix the crash that people run into in practice.

I agree it doesn't fix the wider problem of what to do when SplitEdge fails, but it seems like a good improvement to me.


https://reviews.llvm.org/D24680