diff options
| author | Thomas Helland <[email protected]> | 2015-08-06 13:36:04 +0200 |
|---|---|---|
| committer | Matt Turner <[email protected]> | 2015-08-18 11:34:44 -0700 |
| commit | a39167d5949c76dfb48994caead4b59ab5f80318 (patch) | |
| tree | 4315cc93fbb82078da4295dd299643aff2e5bab1 | |
| parent | 29264d0d0cd5ca24314630d9dc22b3f971344a34 (diff) | |
nir: Simplify fne(fneg(a), a) -> fne(a, 0.0)
-NaN != NaN, and -Inf != Inf, so this should be safe.
Found while working on my VRP pass.
Shader-db results on my IVB:
total instructions in shared programs: 1698267 -> 1698067 (-0.01%)
instructions in affected programs: 15785 -> 15585 (-1.27%)
helped: 36
HURT: 0
GAINED: 0
LOST: 0
Some shaders was found to have the following pattern in NIR:
vec1 ssa_26 = fneg ssa_21
vec1 ssa_27 = fne ssa_21, ssa_26
Make that:
vec1 ssa_27 = fne ssa_21, 0.0f
This is found in Dota2 and Brutal Legend.
One shader is cut by 8%, from 323 -> 296 instructons in SIMD8
Signed-off-by: Thomas Helland <[email protected]>
Reviewed-by: Matt Turner <[email protected]>
| -rw-r--r-- | src/glsl/nir/nir_opt_algebraic.py | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/src/glsl/nir/nir_opt_algebraic.py b/src/glsl/nir/nir_opt_algebraic.py index d7c17403f9f..b76fef236a9 100644 --- a/src/glsl/nir/nir_opt_algebraic.py +++ b/src/glsl/nir/nir_opt_algebraic.py @@ -113,6 +113,7 @@ optimizations = [ (('sge', a, b), ('b2f', ('fge', a, b)), 'options->lower_scmp'), (('seq', a, b), ('b2f', ('feq', a, b)), 'options->lower_scmp'), (('sne', a, b), ('b2f', ('fne', a, b)), 'options->lower_scmp'), + (('fne', ('fneg', a), a), ('fne', a, 0.0)), # Emulating booleans (('imul', ('b2i', a), ('b2i', b)), ('b2i', ('iand', a, b))), (('fmul', ('b2f', a), ('b2f', b)), ('b2f', ('iand', a, b))), |