[llvm] [WebAssembly] Optimize away mask of 63 for shl ( zext (and i32 63))) (PR #152397)

[Luke Lau via llvm-commits]

https://github.com/lukel97 approved this pull request.

LGTM, thanks! If you're looking for a follow up PR, I think the i64 sra/srl patterns can get the same optimisation too right?

https://github.com/llvm/llvm-project/pull/152397