[llvm] [HashRecognize] Fix LHS ConstantRange check for BE (PR #148620)

[Ramkumar Ramachandra via llvm-commits]

artagnon wrote:

> > Pattern-matching a CRC is going to be inherently more fragile.
> 
> What exactly do you mean by "fragile" ? There's already pattern-matching for the shift, the XOR, the select and the compare. I would prefer to have some CRCs not optimized than having non-CRC code miscompiled.

Wouldn't be robust to changes in InstCombine, I mean. No, of course there shouldn't be miscompiles: let me think a bit about whether the ValueEvolution approach could work in theory, and implement pattern-matching otherwise.

https://github.com/llvm/llvm-project/pull/148620