[PATCH] D38388: [DAGCombiner, x86] convert insertelement of bitcasted vector into shuffle

[Sanjay Patel via Phabricator via llvm-commits]

spatel added a comment.

In https://reviews.llvm.org/D38388#884472, @RKSimon wrote:

> I like the idea of #3 (making sure we comment it thoroughly!)


We can make it less hacky by performing the shuffle in the pre-bitcast type. Then, we're not lying about the shuffle. We'll have to bitcast the big vector and then bitcast the result though...and the mask will be less beautiful (it'll be more like what I was trying to create in https://reviews.llvm.org/D38316). But that should still catch the cases we want without adding another hook. Let me draft that and see what breaks... :)


https://reviews.llvm.org/D38388