mirror of
https://gitlab.freedesktop.org/mesa/mesa.git
synced 2025-12-21 22:20:14 +01:00
3c474f8513
If we have fsin or fcos trigonometric operations with constant values
as inputs, we will multiply the result by 0.99997 in
brw_nir_apply_trig_workarounds, making the result wrong.
Adjusting the rules so they do not apply to const values we let a
later constant fold to deal with it.
v2:
- Do not early constant fold but only apply the trig workaround for
non constants (Caio).
- Add fixes tag to commit log (Caio).
Fixes: bfd17c76c1 "i965: Port INTEL_PRECISE_TRIG=1 to NIR."
Signed-off-by: Samuel Iglesias Gonsálvez <siglesias@igalia.com>
Signed-off-by: Andres Gomez <agomez@igalia.com>
Reviewed-by: Caio Marcelo de Oliveira Filho <caio.oliveira@intel.com>
62 lines
2.4 KiB
Python
62 lines
2.4 KiB
Python
#
|
|
# Copyright (C) 2016 Intel Corporation
|
|
#
|
|
# Permission is hereby granted, free of charge, to any person obtaining a
|
|
# copy of this software and associated documentation files (the "Software"),
|
|
# to deal in the Software without restriction, including without limitation
|
|
# the rights to use, copy, modify, merge, publish, distribute, sublicense,
|
|
# and/or sell copies of the Software, and to permit persons to whom the
|
|
# Software is furnished to do so, subject to the following conditions:
|
|
#
|
|
# The above copyright notice and this permission notice (including the next
|
|
# paragraph) shall be included in all copies or substantial portions of the
|
|
# Software.
|
|
#
|
|
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
# THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
# IN THE SOFTWARE.
|
|
|
|
# Prior to Kaby Lake, The SIN and COS instructions on Intel hardware can
|
|
# produce values slightly outside of the [-1.0, 1.0] range for a small set of
|
|
# values. Obviously, this can break everyone's expectations about trig
|
|
# functions. This appears to be fixed in Kaby Lake.
|
|
#
|
|
# According to an internal presentation, the COS instruction can produce
|
|
# a value up to 1.000027 for inputs in the range (0.08296, 0.09888). One
|
|
# suggested workaround is to multiply by 0.99997, scaling down the
|
|
# amplitude slightly. Apparently this also minimizes the error function,
|
|
# reducing the maximum error from 0.00006 to about 0.00003.
|
|
|
|
from __future__ import print_function
|
|
|
|
import argparse
|
|
import sys
|
|
|
|
TRIG_WORKAROUNDS = [
|
|
(('fsin', 'x(is_not_const)'), ('fmul', ('fsin', 'x'), 0.99997)),
|
|
(('fcos', 'x(is_not_const)'), ('fmul', ('fcos', 'x'), 0.99997)),
|
|
]
|
|
|
|
|
|
def main():
|
|
parser = argparse.ArgumentParser()
|
|
parser.add_argument('-p', '--import-path', required=True)
|
|
args = parser.parse_args()
|
|
sys.path.insert(0, args.import_path)
|
|
run()
|
|
|
|
|
|
def run():
|
|
import nir_algebraic # pylint: disable=import-error
|
|
|
|
print('#include "brw_nir.h"')
|
|
print(nir_algebraic.AlgebraicPass("brw_nir_apply_trig_workarounds",
|
|
TRIG_WORKAROUNDS).render())
|
|
|
|
|
|
if __name__ == '__main__':
|
|
main()
|