[Mesa-dev] [PATCH 00/10] i965/fs: Combine constants and unconditionally emit MADs

[Matt Turner]

total instructions in shared programs: 5895414 -> 5747578 (-2.51%)
instructions in affected programs:     3618111 -> 3470275 (-4.09%)
helped:                                20492
HURT:                                  4449
GAINED:                                54
LOST:                                  146

and with NIR, that already emits MADs always:

total instructions in shared programs: 7992936 -> 7772474 (-2.76%)
instructions in affected programs:     3738730 -> 3518268 (-5.90%)
helped:                                22082
HURT:                                  3445
GAINED:                                70
LOST:                                  78

There are some particularly exciting individual improvements too:

kerbal-space-program/667: FS SIMD8: 1024 -> 561 (-45.21%)
kerbal-space-program/676: FS SIMD8: 1021 -> 558 (-45.35%)
rocketbirds-hardboiled-chicken/fp-2: FS SIMD8: 1076 -> 582 (-45.91%)

Changing the fs_visitor and fp backend to always emit MADs is a little
like moving the goal posts for switching to NIR, but I think always
emitting MADs this is the right direction, and of course we'll discover
more improvements the more we work with the code.