nir/algebraic: Use value range analysis to convert fmin to fsat

All Gen8+ platforms had similar results. (Ice Lake shown)
total instructions in shared programs: 16297320 -> 16282006 (-0.09%)
instructions in affected programs: 2434498 -> 2419184 (-0.63%)
helped: 8091
HURT: 1
helped stats (abs) min: 1 max: 51 x̄: 1.89 x̃: 2
helped stats (rel) min: 0.04% max: 14.29% x̄: 0.98% x̃: 0.95%
HURT stats (abs)   min: 7 max: 7 x̄: 7.00 x̃: 7
HURT stats (rel)   min: 0.28% max: 0.28% x̄: 0.28% x̃: 0.28%
95% mean confidence interval for instructions value: -1.94 -1.85
95% mean confidence interval for instructions %-change: -0.99% -0.96%
Instructions are helped.

total cycles in shared programs: 367221624 -> 367168597 (-0.01%)
cycles in affected programs: 126409635 -> 126356608 (-0.04%)
helped: 5612
HURT: 1023
helped stats (abs) min: 1 max: 2332 x̄: 31.11 x̃: 16
helped stats (rel) min: <.01% max: 30.31% x̄: 1.69% x̃: 1.42%
HURT stats (abs)   min: 1 max: 2372 x̄: 118.84 x̃: 16
HURT stats (rel)   min: <.01% max: 46.98% x̄: 1.46% x̃: 0.35%
95% mean confidence interval for cycles value: -11.52 -4.46
95% mean confidence interval for cycles %-change: -1.26% -1.14%
Cycles are helped.

total spills in shared programs: 8868 -> 8870 (0.02%)
spills in affected programs: 28 -> 30 (7.14%)
helped: 0
HURT: 1

total fills in shared programs: 21903 -> 21904 (<.01%)
fills in affected programs: 42 -> 43 (2.38%)
helped: 0
HURT: 1

Haswell
total instructions in shared programs: 13353925 -> 13338728 (-0.11%)
instructions in affected programs: 2265850 -> 2250653 (-0.67%)
helped: 8127
HURT: 5
helped stats (abs) min: 1 max: 51 x̄: 1.88 x̃: 2
helped stats (rel) min: 0.04% max: 20.00% x̄: 1.13% x̃: 1.07%
HURT stats (abs)   min: 5 max: 16 x̄: 9.00 x̃: 6
HURT stats (rel)   min: 0.19% max: 0.52% x̄: 0.35% x̃: 0.28%
95% mean confidence interval for instructions value: -1.91 -1.83
95% mean confidence interval for instructions %-change: -1.15% -1.11%
Instructions are helped.

total cycles in shared programs: 375535444 -> 375536343 (<.01%)
cycles in affected programs: 131206582 -> 131207481 (<.01%)
helped: 5590
HURT: 1055
helped stats (abs) min: 1 max: 2844 x̄: 34.15 x̃: 16
helped stats (rel) min: <.01% max: 21.57% x̄: 2.08% x̃: 1.60%
HURT stats (abs)   min: 1 max: 2487 x̄: 181.78 x̃: 21
HURT stats (rel)   min: <.01% max: 40.66% x̄: 1.96% x̃: 0.37%
95% mean confidence interval for cycles value: -4.74 5.01
95% mean confidence interval for cycles %-change: -1.51% -1.37%
Inconclusive result (value mean confidence interval includes 0).

total spills in shared programs: 23401 -> 23407 (0.03%)
spills in affected programs: 248 -> 254 (2.42%)
helped: 2
HURT: 5

total fills in shared programs: 34850 -> 34845 (-0.01%)
fills in affected programs: 383 -> 378 (-1.31%)
helped: 2
HURT: 5

Ivy Bridge
total instructions in shared programs: 11975423 -> 11968117 (-0.06%)
instructions in affected programs: 845703 -> 838397 (-0.86%)
helped: 4071
HURT: 0
helped stats (abs) min: 1 max: 51 x̄: 1.79 x̃: 1
helped stats (rel) min: 0.08% max: 8.21% x̄: 1.04% x̃: 0.93%
95% mean confidence interval for instructions value: -1.87 -1.71
95% mean confidence interval for instructions %-change: -1.06% -1.02%
Instructions are helped.

total cycles in shared programs: 179674318 -> 179635552 (-0.02%)
cycles in affected programs: 5100065 -> 5061299 (-0.76%)
helped: 2650
HURT: 611
helped stats (abs) min: 1 max: 900 x̄: 21.85 x̃: 16
helped stats (rel) min: <.01% max: 21.55% x̄: 2.39% x̃: 1.40%
HURT stats (abs)   min: 1 max: 1841 x̄: 31.33 x̃: 6
HURT stats (rel)   min: <.01% max: 58.71% x̄: 1.64% x̃: 0.37%
95% mean confidence interval for cycles value: -14.14 -9.64
95% mean confidence interval for cycles %-change: -1.75% -1.52%
Cycles are helped.

LOST:   3
GAINED: 7

Sandy Bridge
total instructions in shared programs: 10828844 -> 10824272 (-0.04%)
instructions in affected programs: 525678 -> 521106 (-0.87%)
helped: 2386
HURT: 0
helped stats (abs) min: 1 max: 51 x̄: 1.92 x̃: 2
helped stats (rel) min: 0.11% max: 7.96% x̄: 1.05% x̃: 0.94%
95% mean confidence interval for instructions value: -2.04 -1.80
95% mean confidence interval for instructions %-change: -1.08% -1.03%
Instructions are helped.

total cycles in shared programs: 154024591 -> 154009894 (<.01%)
cycles in affected programs: 4005766 -> 3991069 (-0.37%)
helped: 1245
HURT: 506
helped stats (abs) min: 1 max: 585 x̄: 21.07 x̃: 16
helped stats (rel) min: 0.02% max: 11.57% x̄: 1.98% x̃: 0.83%
HURT stats (abs)   min: 1 max: 639 x̄: 22.81 x̃: 6
HURT stats (rel)   min: 0.01% max: 26.21% x̄: 1.07% x̃: 0.26%
95% mean confidence interval for cycles value: -10.57 -6.21
95% mean confidence interval for cycles %-change: -1.23% -0.97%
Cycles are helped.

GM45 and Iron Lake had similar results. (Iron Lake shown)
total instructions in shared programs: 8137248 -> 8135196 (-0.03%)
instructions in affected programs: 148322 -> 146270 (-1.38%)
helped: 992
HURT: 0
helped stats (abs) min: 1 max: 32 x̄: 2.07 x̃: 2
helped stats (rel) min: 0.41% max: 9.73% x̄: 1.74% x̃: 1.51%
95% mean confidence interval for instructions value: -2.16 -1.98
95% mean confidence interval for instructions %-change: -1.80% -1.67%
Instructions are helped.

total cycles in shared programs: 188583424 -> 188575724 (<.01%)
cycles in affected programs: 4409620 -> 4401920 (-0.17%)
helped: 956
HURT: 6
helped stats (abs) min: 2 max: 168 x̄: 8.09 x̃: 8
helped stats (rel) min: 0.04% max: 6.76% x̄: 0.27% x̃: 0.18%
HURT stats (abs)   min: 6 max: 6 x̄: 6.00 x̃: 6
HURT stats (rel)   min: 0.10% max: 0.10% x̄: 0.10% x̃: 0.10%
95% mean confidence interval for cycles value: -8.41 -7.60
95% mean confidence interval for cycles %-change: -0.29% -0.25%
Cycles are helped.

Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>

diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py
index 0711f491a4c543e6d10c544eddb6faea11543399..d815db355bb1bbcf16f353fa1944556cfaca69c3 100644 (file)
--- a/src/compiler/nir/nir_opt_algebraic.py
+++ b/src/compiler/nir/nir_opt_algebraic.py
@@ -789,7 +789,7 @@ optimizations = [
    (('ilt', ('f2u', a), b), ('ilt', ('f2i', a), b)),
    (('ilt', b, ('f2u', a)), ('ilt', b, ('f2i', a))),
 
-   (('~fmin', ('fabs', a), 1.0), ('fsat', ('fabs', a)), '!options->lower_fsat'),
+   (('~fmin', 'a(is_not_negative)', 1.0), ('fsat', a), '!options->lower_fsat'),
 
    # The result of the multiply must be in [-1, 0], so the result of the ffma
    # must be in [0, 1].