diff options
| author | Jason Ekstrand <[email protected]> | 2019-07-12 23:26:48 -0500 |
|---|---|---|
| committer | Jason Ekstrand <[email protected]> | 2019-07-17 18:44:35 +0000 |
| commit | e8505e982a3f911440cad8a963313d2d62d27fc6 (patch) | |
| tree | bb8bb9296e4f4106e4d13a7ebeb001c64ff2361d /src | |
| parent | 9fed031e4eb05a78888fb061a17eeb7346cc43d2 (diff) | |
nir/algebraic: Optimize comparing unpacked values
We could, in theory, add the same optimization for 64-bit unpack
operations but that's likely to fight with 64-bit integer lowering on
platforms which require it so it will require more infrastructure before
that will be a good idea.
Reviewed-by: Matt Turner <[email protected]>
Diffstat (limited to 'src')
| -rw-r--r-- | src/compiler/nir/nir_opt_algebraic.py | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py index 6ae937651e0..42462d5befa 100644 --- a/src/compiler/nir/nir_opt_algebraic.py +++ b/src/compiler/nir/nir_opt_algebraic.py @@ -722,6 +722,14 @@ optimizations = [ (('pack_64_2x32_split', ('unpack_64_2x32_split_x', a), ('unpack_64_2x32_split_y', a)), a), + # Comparing two halves of an unpack separately. While this optimization + # should be correct for non-constant values, it's less obvious that it's + # useful in that case. For constant values, the pack will fold and we're + # guaranteed to reduce the whole tree to one instruction. + (('iand', ('ieq', ('unpack_32_2x16_split_x', a), '#b'), + ('ieq', ('unpack_32_2x16_split_y', a), '#c')), + ('ieq', a, ('pack_32_2x16_split', b, c))), + # Byte extraction (('ushr', 'a@16', 8), ('extract_u8', a, 1), '!options->lower_extract_byte'), (('ushr', 'a@32', 24), ('extract_u8', a, 3), '!options->lower_extract_byte'), |