[llvm] [AMDGPU][SDAG] Legalise v2i32 or/xor/and instructions to make use of 64-bit wide instructions (PR #140694)

[Chris Jackson via llvm-commits]

chrisjbris wrote:

Rebased to bring in fp srcmods on integer select :https://github.com/llvm/llvm-project/commit/9f102a90042fd3757c207112cfe64ee10182ace5 and appropriate modifications made.

https://github.com/llvm/llvm-project/pull/140694