This allows our optimizer to recognize this and eliminate it when
it can prove that the s_and with exec is unneeded.
Fossil DB changes on Sienna Cichlid:
Totals from 1969 (1.53% of 128647) affected shaders:
CodeSize: 9468228 -> 9469348 (+0.01%); split: -0.00%, +0.01%
Instrs: 1773566 -> 1773581 (+0.00%); split: -0.01%, +0.01%
Latency: 19504042 -> 19503385 (-0.00%); split: -0.00%, +0.00%
InvThroughput: 3617406 -> 3617333 (-0.00%)
Copies: 108998 -> 110592 (+1.46%)
Signed-off-by: Timur Kristóf <timur.kristof@gmail.com>
Reviewed-by: Daniel Schürmann <daniel@schuermann.dev>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/11458>