[llvm] [AMDGPU][SDAG] Support source modifiers on select integer operands (PR #147325)

[Chris Jackson via llvm-commits]

chrisjbris wrote:

> > Thanks to all reviewers but I think I need to deprecate this PR in favour of the simpler #149110.
> 
> On average it's probably better to do it that way. However, we don't have any of the combines trying to make the form match for integers. So on this path, there's additional work to actively try to form this

Yes I've already begun this work by rebasing on top of the new srcmod patch and adapting to legal v2i32, also modifying  SITargetLowering::performXorCombine where appropriate.

https://github.com/llvm/llvm-project/pull/147325