Previously, the lowering was for 8/16/64-bit values, or 8/16-component
vectors. Now, it also handles write masks on 32-bit 1/2/3/4-component
vectors.
DXIL looks like it supports putting an interesting write mask in the
buffer store intrinsic, but DXC never generates stores with write
masks, and multiple drivers completely ignore the write mask.
Also, set the write mask properly on the output intrinsic.
Reviewed-by: Sil Vilerino <sivileri@microsoft.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/14294>
Jesse Natalie
c375b05bfe