diff options
| author | Samuel Pitoiset <samuel.pitoiset@gmail.com> | 2020-02-04 17:25:35 +0100 |
|---|---|---|
| committer | Dylan Baker <dylan@pnwbakers.com> | 2020-02-11 09:49:15 -0800 |
| commit | fa0dcef2ef2fa41350b867793bb658a48a04e676 (patch) | |
| tree | 6a77c94303a598ca639586c9f4d5b546b51d0e5d | |
| parent | 4558bdb95aa11863780d3a4eed593e6f624222d8 (diff) | |
nir: do not use De Morgan's Law rules for flt and fge
In presence of NaNs, "!(flt(a, b) && flt(c, d))" is NOT EQUAL
to "fge(a, b) || fge(c, d)". These optimizations are unsafe for
apps that rely on NaN behaviour.
pipeline-db (GFX9/LLVM):
Totals from affected shaders:
SGPRS: 3176 -> 3136 (-1.26 %)
VGPRS: 2188 -> 2144 (-2.01 %)
Spilled SGPRs: 227 -> 169 (-25.55 %)
Code Size: 150572 -> 151800 (0.82 %) bytes
Max Waves: 307 -> 310 (0.98 %)
pipeline-db (GFX9/ACO):
Totals from affected shaders:
SGPRS: 18744 -> 18744 (0.00 %)
VGPRS: 15576 -> 15580 (0.03 %)
Spilled SGPRs: 164 -> 164 (0.00 %)
Code Size: 1573012 -> 1576492 (0.22 %) bytes
Max Waves: 1534 -> 1532 (-0.13 %)
Closes: https://gitlab.freedesktop.org/mesa/mesa/issues/2127
Fixes: d1ed4ffe0b7 ("nir: Use De Morgan's Law on logic compounded comparisons")
Signed-off-by: Samuel Pitoiset <samuel.pitoiset@gmail.com>
Reviewed-by: Ian Romanick <ian.d.romanick@intel.com>
Tested-by: Marge Bot <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3696>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/merge_requests/3696>
(cherry picked from commit 8e7728077435c5c5ad8c328761277f8ff3b32112)
| -rw-r--r-- | .pick_status.json | 2 | ||||
| -rw-r--r-- | src/compiler/nir/nir_opt_algebraic.py | 2 |
2 files changed, 2 insertions, 2 deletions
diff --git a/.pick_status.json b/.pick_status.json index b284884ae11..c5c84650255 100644 --- a/.pick_status.json +++ b/.pick_status.json @@ -13,7 +13,7 @@ "description": "nir: do not use De Morgan's Law rules for flt and fge", "nominated": true, "nomination_type": 1, - "resolution": 0, + "resolution": 1, "master_sha": null, "because_sha": "d1ed4ffe0b70762477709e699f95c73602f9dc5a" }, diff --git a/src/compiler/nir/nir_opt_algebraic.py b/src/compiler/nir/nir_opt_algebraic.py index f9fc119505f..904b02e0309 100644 --- a/src/compiler/nir/nir_opt_algebraic.py +++ b/src/compiler/nir/nir_opt_algebraic.py @@ -1279,7 +1279,7 @@ for bit_size in [8, 16, 32, 64]: ('bcsel', ('ilt', a, ('isub', a, b)), intmin, ('isub', a, b))), 'options->lower_add_sat'), ] -invert = OrderedDict([('feq', 'fne'), ('fne', 'feq'), ('fge', 'flt'), ('flt', 'fge')]) +invert = OrderedDict([('feq', 'fne'), ('fne', 'feq')]) for left, right in itertools.combinations_with_replacement(invert.keys(), 2): optimizations.append((('inot', ('ior(is_used_once)', (left, a, b), (right, c, d))), |