[llvm-branch-commits] [llvm] AMDGPU: Reduce 64-bit add width if low bits are known 0 (PR #122049)

[Jay Foad via llvm-branch-commits]

jayfoad wrote:

Why doesn't this fall out naturally from splitting the 64-bit add into 32-bit parts and then simplifying each part? Do we leave it as a 64-bit add all the way until final instruction selection?

https://github.com/llvm/llvm-project/pull/122049