[llvm] [GlobalISel] Implement G_UADDO/G_UADDE/G_SADDO/G_SADDE for computeKnownBits (PR #165497)

[Yatao Wang via llvm-commits]

https://github.com/ningxinr commented:

Hi Simon and Matt, would either of you help me with the questions regarding the `SADD[OE]`? Thanks!

https://github.com/llvm/llvm-project/pull/165497