intel/compiler: More peephole_select for pre-Gen6

intel/compiler: More peephole_select for pre-Gen6

No shader-db changes on any Gen6+ platform.

All of the shaders with cycles hurt by more than ~2% are from Master of
Orion.  All of the shaders have instructions helped.  It looks like the
pass enables some control flow to be converted to bcsels, then the
scheduler does dumb things.  These are new shaders (just added before
doing this shader-db run), so there's probably some low-hanging fruit.

Iron Lake
total instructions in shared programs: 8214327 -> 8213684 (<.01%)
instructions in affected programs: 84469 -> 83826 (-0.76%)
helped: 114
HURT: 26
helped stats (abs) min: 2 max: 18 x̄: 7.75 x̃: 9
helped stats (rel) min: 0.17% max: 13.73% x̄: 2.52% x̃: 1.05%
HURT stats (abs)   min: 2 max: 20 x̄: 9.23 x̃: 8
HURT stats (rel)   min: 0.70% max: 2.48% x̄: 1.66% x̃: 1.61%
95% mean confidence interval for instructions value: -5.87 -3.32
95% mean confidence interval for instructions %-change: -2.32% -1.17%
Instructions are helped.

total cycles in shared programs: 187736850 -> 187749314 (<.01%)
cycles in affected programs: 506750 -> 519214 (2.46%)
helped: 104
HURT: 36
helped stats (abs) min: 2 max: 72 x̄: 21.96 x̃: 16
helped stats (rel) min: 0.02% max: 6.16% x̄: 0.97% x̃: 0.63%
HURT stats (abs)   min: 4 max: 1402 x̄: 409.67 x̃: 40
HURT stats (rel)   min: 0.33% max: 23.12% x̄: 5.79% x̃: 1.39%
95% mean confidence interval for cycles value: 28.32 149.74
95% mean confidence interval for cycles %-change: -0.07% 1.61%
Inconclusive result (%-change mean confidence interval includes 0).

GM45
total instructions in shared programs: 5044014 -> 5043652 (<.01%)
instructions in affected programs: 46751 -> 46389 (-0.77%)
helped: 63
HURT: 13
helped stats (abs) min: 2 max: 29 x̄: 7.65 x̃: 9
helped stats (rel) min: 0.17% max: 13.73% x̄: 2.93% x̃: 1.04%
HURT stats (abs)   min: 2 max: 20 x̄: 9.23 x̃: 8
HURT stats (rel)   min: 0.66% max: 2.35% x̄: 1.58% x̃: 1.52%
95% mean confidence interval for instructions value: -6.54 -2.99
95% mean confidence interval for instructions %-change: -3.04% -1.28%
Instructions are helped.

total cycles in shared programs: 128143042 -> 128150188 (<.01%)
cycles in affected programs: 324564 -> 331710 (2.20%)
helped: 57
HURT: 19
helped stats (abs) min: 6 max: 74 x̄: 30.70 x̃: 32
helped stats (rel) min: 0.08% max: 4.74% x̄: 1.22% x̃: 0.81%
HURT stats (abs)   min: 10 max: 1400 x̄: 468.21 x̃: 60
HURT stats (rel)   min: 0.56% max: 19.94% x̄: 5.80% x̃: 1.70%
95% mean confidence interval for cycles value: 6.90 181.15
95% mean confidence interval for cycles %-change: -0.52% 1.59%
Inconclusive result (%-change mean confidence interval includes 0).

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Acked-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>