LD_VAR_BUF instructions on Valhall take a source format, indicating the
in-memory format of the varying independent from the register format, which we
still model within the compiler for compatibility with Bifrost. (Prior to
Valhall, source format is specified in the attribute descriptor as a physical
pixel format.)
Model this information, allowing us to generate fp16 LD_VAR_BUF instructions
correctly on Valhall.
Signed-off-by: Alyssa Rosenzweig <alyssa@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/16752>
93f69e4b1c