[llvm] [VectorCombine] foldBitcastShuffle - peek through any residual bitcasts before creating a new bitcast on top (PR #86119)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

> > I'm assuming we can't safely put this inside IRBuilderBase.CreateBitCast?
> 
> FYI, folding bitcast of bitcast is always safe.

It was mainly potential OneUse restrictions that concerned me. VectorCombine won't mind but I can imagine there are cases where it would be a problem.



https://github.com/llvm/llvm-project/pull/86119