nir: Recognize (a < b || a < c) as a < max(b, c).

Doesn't work for analogous && cases, because of NaNs.

total instructions in shared programs: 6195712 -> 6194829 (-0.01%)
instructions in affected programs:     42000 -> 41117 (-2.10%)
helped:                                403

Reviewed-by: Eric Anholt <eric@anholt.net>

diff --git a/src/glsl/nir/nir_opt_algebraic.py b/src/glsl/nir/nir_opt_algebraic.py
index 3a3e6bfabb26c8a45ae57da011da77326cf56625..6181f5df7a486b9fb7996c21e0d96b78c1753ce6 100644 (file)
--- a/src/glsl/nir/nir_opt_algebraic.py
+++ b/src/glsl/nir/nir_opt_algebraic.py
@@ -94,6 +94,8 @@ optimizations = [
    (('fsat', a), ('fmin', ('fmax', a, 0.0), 1.0), 'options->lower_fsat'),
    (('fsat', ('fsat', a)), ('fsat', a)),
    (('fmin', ('fmax', ('fmin', ('fmax', a, 0.0), 1.0), 0.0), 1.0), ('fmin', ('fmax', a, 0.0), 1.0)),
+   (('ior', ('flt', a, b), ('flt', a, c)), ('flt', a, ('fmax', b, c))),
+   (('ior', ('fge', a, b), ('fge', a, c)), ('fge', a, ('fmin', b, c))),
    # Emulating booleans
    (('fmul', ('b2f', a), ('b2f', b)), ('b2f', ('iand', a, b))),
    (('fsat', ('fadd', ('b2f', a), ('b2f', b))), ('b2f', ('ior', a, b))),