[llvm] [InstCombine] Fold select(X >s 0, 0, -X) | smax(X, 0) to abs(X) (PR #165200)

[Wenju He via llvm-commits]

wenju-he wrote:

> Can you add alive2 link

done. Updated commit message:
https://alive2.llvm.org/ce/z/2-brvr
https://alive2.llvm.org/ce/z/Dowjzk

https://github.com/llvm/llvm-project/pull/165200