[llvm] [InstCombine]: Missed Optimization, treat the disjoint Or as an add (PR #86340)

[Craig Topper via llvm-commits]

topperc wrote:

I had written half of this in this PR https://github.com/llvm/llvm-project/pull/76981 I did not get around to looking at @nikic concerns there.

https://github.com/llvm/llvm-project/pull/86340