AMD GFX941 & GFX942 GPU Targets Added To LLVM Compiler

Going back to last year there's been AMD GFX940 work within the LLVM compiler for its AMDGPU compiler back-end. That AMD GFX940 should align to the Instinct MI300 while introduced to the latest LLVM compiler code today are new GFX941 and GFX942 targets.

Prior to today the only AMD GFX941/GFX942 hits have been "GFX941" being referenced in regards to some AMDKFD kernel driver debug patches and AMDGFX942 getting brought up within some ROCm code. Most of the AMD Instinct MI300 bring-up the past year has been as "GFX940" though in recent weeks there's also been GFX943 bring-up within the AMDGPU/AMDKFD kernel drivers. But appearing today in LLVM is these GFX941 and GFX942 targets for likely some additional models in the Instinct MI300 line-up.

This commit added GFX941 and this commit added GFX942. When looking at the defined feature sets, there are no expressed differences at this point compared to GFX940. We'll see if follow-up commits to LLVM end up making any more invasive feature changes to the GFX941 or GFX942 targets.

In any event, AMD's open-source upstreaming work continues in preparing their next-gen accelerator parts for Linux use.