[clang] [llvm] [ValueTracking] Add dominating condition support in computeKnownBits() (PR #73662)

[Nikita Popov via cfe-commits]

nikic wrote:

I went ahead and pushed a clean up version of that change to this PR, so you can just re-test this PR.

I've found that dropping the icmp case also removes most of the second-order compile-time regressions, and also drops the (very minor) regression in the BPF test, so those are also points in favor of doing this.

https://github.com/llvm/llvm-project/pull/73662