Mesa (master): nir: add another comparison simplification

[Timothy Arceri]

Module: Mesa
Branch: master
Commit: 1130f82a88ff4e7960e5a8d72db41e1b98431446
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=1130f82a88ff4e7960e5a8d72db41e1b98431446

Author: Timothy Arceri <timothy.arceri at collabora.com>
Date:   Wed Jan  4 16:21:34 2017 +1100

nir: add another comparison simplification

On BDW:

total instructions in shared programs: 13061877 -> 13060965 (-0.01%)
instructions in affected programs: 133569 -> 132657 (-0.68%)
helped: 566
HURT: 0

total cycles in shared programs: 256611784 -> 256599536 (-0.00%)
cycles in affected programs: 861016 -> 848768 (-1.42%)
helped: 379
HURT: 73

Reviewed-by: Jason Ekstrand <jason at jlekstrand.net>

---

 src/compiler/nir/nir_opt_algebraic.py | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py
index 434881f..85cdc7b 100644
--- a/src/compiler/nir/nir_opt_algebraic.py
+++ b/src/compiler/nir/nir_opt_algebraic.py
@@ -150,6 +150,8 @@ optimizations = [
    # inot(a)
    (('fge', 0.0, ('b2f', a)), ('inot', a)),
 
+   (('fge', ('fneg', ('b2f', a)), 0.0), ('inot', a)),
+
    # 0.0 < fabs(a)
    # fabs(a) > 0.0
    # fabs(a) != 0.0 because fabs(a) must be >= 0