wasm: recognize `any_true` and `all_true` (#155885)
fixes https://github.com/llvm/llvm-project/issues/129441
cc @lukel97 @badumbatish
https://github.com/llvm/llvm-project/pull/145108
I've been learning a bit about LLVM, trying to make progress on some of
these issues. The code below is based on
https://github.com/llvm/llvm-project/pull/145108#issuecomment-3004561085,
by implementing `shouldExpandReduction`.
The implementation works for the test cases I added, but (obviously)
fails for any existing cases. `ISD::VECREDUCE_AND` and
`ISD::VECREDUCE_OR` are now marked as legal, which is required for the
`Pat`s to fire, but when they don't that causes a selection failure.
So, I'm wondering, what is the right approach here. Should I mark these
intrinsics as `Custom` instead and manually perform the transformation
in C++? Or is there some trick to still get the default lowering (a
series of loads and scalar bitwise operations) when the patterns don't
fire?
