[llvm] [LLVM] Slay undead copysign code (PR #111269)

[via llvm-commits]

workingjubilee wrote:

@arsenm I can do further edits to this if you want but I cannot merge this, so I am wondering what it would take? I am wondering if it was a mistake to try to solve the problem you expressed discontent about. You seemed inclined to accept the PR in its then-current state but all successive edits that try to remove the vestigial code so that PowerPC would no longer be the odd one out that is "left behind" by this change have provoked many questions.

https://github.com/llvm/llvm-project/pull/111269