i965/fs: Emit MAD instructions when possible.
Previously we didn't emit MAD instructions since they cannot take
immediate arguments, but with the opt_combine_constants() pass we can
handle this properly.
total instructions in shared programs: 5920017 -> 5733278 (-3.15%)
instructions in affected programs: 3625153 -> 3438414 (-5.15%)
helped: 22017
HURT: 870
GAINED: 91
LOST: 49
Without constant pooling, this patch is a complete loss:
total instructions in shared programs: 5912589 -> 5987888 (1.27%)
instructions in affected programs: 3190050 -> 3265349 (2.36%)
helped: 1564
HURT: 17827
GAINED: 27
LOST: 101
And since the constant pooling patch by itself hurt a bunch of things,
from before constant pooling to this patch the results are:
total instructions in shared programs: 5895414 -> 5747946 (-2.50%)
instructions in affected programs: 3617993 -> 3470525 (-4.08%)
helped: 20478
HURT: 4469
GAINED: 54
LOST: 146
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>