[llvm-branch-commits] [llvm] release/18.x: [InstCombine] Drop nuw flag when CtlzOp is a sub nuw (#91776) (PR #91917)

[Tom Stellard via llvm-branch-commits]

tstellar wrote:

@dtcxzyw (or anyone else). If you would like to add a note about this fix in the release notes (completely optional). Please reply to this comment with a one or two sentence description of the fix.  When you are done, please add the release:note label to this PR.

https://github.com/llvm/llvm-project/pull/91917