[NVPTX] Improve lowering of v4i8#67866

Merged

Artem-B merged 13 commits intollvm:mainfrom

Artem-B:v4i8reg

Oct 9, 2023

Commits on Sep 29, 2023

[NVPTX] Improve lowering of v4i8
Artem-B
committed

Commits on Oct 3, 2023

More work on fleshing out extractelt/build_vector for v4i8
Artem-B
committed

Commits on Oct 9, 2023