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

[Nikita Popov via cfe-commits]

nikic wrote:

The problem for mpeg2decode seems to be that we do more `add` to `or disjoint` conversions. But `or disjoint` is still being implemented, so e.g. in SCEV we don't recognize it yet and fail to create an `add` SCEV for it. So I think we need to do some more work on `or disjoint` and then try again.

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