[llvm] [ValueTracking] Extend LHS/RHS with matching operand to work without constants. (PR #85557)

[via llvm-commits]

goldsteinn wrote:

> > The only really thing I can think of is to preserve the information w/ assumes
> > when we fold a single use shr exact.
> 
> We met the same issue in [dtcxzyw/llvm-opt-benchmark#49 (comment)](https://github.com/dtcxzyw/llvm-opt-benchmark/pull/49#issuecomment-1870196457).

Yeah I think its a fairly common issue. And it seems you guys
reached the same conclusions.

https://github.com/llvm/llvm-project/pull/85557