[llvm] [ValueTracking] Refine known bits for linear interpolation patterns (PR #166378)

[Valeriy Savchenko via llvm-commits]

SavchenkoValeriy wrote:

Alive2 struggles (times out) with 32 bit vectors for this particular proof: https://alive2.llvm.org/ce/z/S-78k-
In my z3 proof, even 16 bit took quite some times.

https://github.com/llvm/llvm-project/pull/166378