[llvm] [DAG] Fold trunc(abdu(x, y)) and trunc(abds(x, y)) if they have sufficient leading zero/sign bits (PR #151471)

[Simon Pilgrim via llvm-commits]

https://github.com/RKSimon commented:

Its very likely that this patch and #152273 can share the same code inside visitTRUNCATE

https://github.com/llvm/llvm-project/pull/151471