Copy propagation would incorrectly occur in this code
mov(16) v4+2.0:UW, u0<0>:UW NoMask
...
mov(8) v6+2.0:UD, v4+2.0:UD NoMask group0
to create
mov(16) v4+2.0:UW, u0<0>:UW NoMask
...
mov(8) v6+2.0:UD, u0<0>:UD NoMask group0
This has different behavior. I think I just made a mistake when I
changed this condition in e3f502e007.
It seems like this condition could be relaxed to cover cases like (note
the change of destination stride)
mov(16) v4+2.0<2>:UW, u0<0>:UW NoMask
...
mov(8) v6+2.0:UD, v4+2.0:UD NoMask group0
I'm not sure it's worth it.
No shader-db or fossil-db changes on any Intel platform. Even the code
for the test case mentioned in the original commit did not change.
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Fixes: e3f502e007 ("intel/fs: Allow copy propagation between MOVs of mixed sizes")
Closes: #12116
(cherry picked from commit 80a5d158ae)
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32119>
1e792b0933