nir/algebraic: Recognize (a < 0 || 0 < b) as min(a, -b) < 0

Similar to commit 97e6c1b9 and f5cf74d8ba8c.

First apply 0 < b => -b < 0 to get (a < 0 || -b < 0), then apply some
pre-existing rules to get min(a, -b) < 0.

v2: Substantially update the comment explaining the use of is_used_once
and the duplication of patterns.  Suggested by Caio.  Also, while flt
and fge are not commutative, ior and iand are.  Half of the original
patterns were redundant, so delete them.  As alternate justification for
deleting them, fmin(a, -b) < 0 <=> 0 < fmax(-a, b).  Proof left as an
exercise for the reader.

All Gen7+ platforms had similar results. (Ice Lake shown)
total instructions in shared programs: 16333789 -> 16333713 (<.01%)
instructions in affected programs: 11424 -> 11348 (-0.67%)
helped: 32
HURT: 0
helped stats (abs) min: 1 max: 7 x̄: 2.38 x̃: 2
helped stats (rel) min: 0.20% max: 1.67% x̄: 0.76% x̃: 0.69%
95% mean confidence interval for instructions value: -3.03 -1.72
95% mean confidence interval for instructions %-change: -0.89% -0.62%
Instructions are helped.

total cycles in shared programs: 367598295 -> 367596791 (<.01%)
cycles in affected programs: 141414 -> 139910 (-1.06%)
helped: 23
HURT: 6
helped stats (abs) min: 3 max: 386 x̄: 72.52 x̃: 20
helped stats (rel) min: 0.15% max: 4.86% x̄: 1.01% x̃: 0.76%
HURT stats (abs)   min: 4 max: 88 x̄: 27.33 x̃: 12
HURT stats (rel)   min: 0.22% max: 3.95% x̄: 1.08% x̃: 0.59%
95% mean confidence interval for cycles value: -93.51 -10.21
95% mean confidence interval for cycles %-change: -1.10% -0.05%
Cycles are helped.

total instructions in shared programs: 10830836 -> 10830779 (<.01%)
instructions in affected programs: 6895 -> 6838 (-0.83%)
helped: 12
HURT: 0
helped stats (abs) min: 1 max: 14 x̄: 4.75 x̃: 1
helped stats (rel) min: 0.14% max: 1.61% x̄: 0.65% x̃: 0.33%
95% mean confidence interval for instructions value: -8.46 -1.04
95% mean confidence interval for instructions %-change: -1.03% -0.27%
Instructions are helped.

total cycles in shared programs: 154028477 -> 154032740 (<.01%)
cycles in affected programs: 178433 -> 182696 (2.39%)
helped: 3
HURT: 9
helped stats (abs) min: 3 max: 20 x̄: 11.00 x̃: 10
helped stats (rel) min: 0.07% max: 0.20% x̄: 0.12% x̃: 0.09%
HURT stats (abs)   min: 27 max: 1415 x̄: 477.33 x̃: 262
HURT stats (rel)   min: 0.22% max: 6.45% x̄: 2.49% x̃: 1.76%
95% mean confidence interval for cycles value: 28.68 681.82
95% mean confidence interval for cycles %-change: 0.37% 3.30%
Cycles are HURT.

Iron Lake
total instructions in shared programs: 8137966 -> 8137992 (<.01%)
instructions in affected programs: 3281 -> 3307 (0.79%)
helped: 0
HURT: 6
HURT stats (abs)   min: 3 max: 7 x̄: 4.33 x̃: 3
HURT stats (rel)   min: 0.63% max: 1.01% x̄: 0.76% x̃: 0.64%
95% mean confidence interval for instructions value: 2.17 6.50
95% mean confidence interval for instructions %-change: 0.56% 0.96%
Instructions are HURT.

total cycles in shared programs: 188539386 -> 188540038 (<.01%)
cycles in affected programs: 103826 -> 104478 (0.63%)
helped: 0
HURT: 7
HURT stats (abs)   min: 16 max: 218 x̄: 93.14 x̃: 80
HURT stats (rel)   min: 0.14% max: 0.95% x̄: 0.53% x̃: 0.46%
95% mean confidence interval for cycles value: 10.26 176.02
95% mean confidence interval for cycles %-change: 0.24% 0.81%
Cycles are HURT.

GM45
total instructions in shared programs: 5008876 -> 5008889 (<.01%)
instructions in affected programs: 1645 -> 1658 (0.79%)
helped: 0
HURT: 3
HURT stats (abs)   min: 3 max: 7 x̄: 4.33 x̃: 3
HURT stats (rel)   min: 0.63% max: 1.00% x̄: 0.76% x̃: 0.63%

total cycles in shared programs: 128968950 -> 128969426 (<.01%)
cycles in affected programs: 64854 -> 65330 (0.73%)
helped: 0
HURT: 4
HURT stats (abs)   min: 18 max: 218 x̄: 119.00 x̃: 120
HURT stats (rel)   min: 0.14% max: 0.95% x̄: 0.60% x̃: 0.66%
95% mean confidence interval for cycles value: -62.92 300.92
95% mean confidence interval for cycles %-change: -0.05% 1.26%
Inconclusive result (value mean confidence interval includes 0).

Reviewed-by: Caio Marcelo de Oliveira Filho <[email protected]>

0 files changed, 0 insertions, 0 deletions