Jason Ekstrand
05a37e2422
There's a recently discovered HW bug affecting hardware at least as far
back as Skylake where, if the LOD is out-of-bounds for any SIMD lane,
then garbage may be returned in all SIMD lanes. The easy solution is to
set lower_txs_lod so that we always have a constant LOD of 0 which we
know a priori is always in-bounds. Fortunately, not many shaders
actually use textureSize() with LOD.
Shader-db results on Ice Lake:
total instructions in shared programs: 19948537 -> 19948564 (<.01%)
instructions in affected programs: 3859 -> 3886 (0.70%)
helped: 0
HURT: 7
One of the shaders is in Civilization: Beyond Earth, and the rest are
all in Civilization VI.
Reviewed-by: Francisco Jerez <currojerez@riseup.net>
Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com>
Cc: mesa-stable@lists.freedesktop.org
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/10538>
`Mesa <https://mesa3d.org>`_ - The 3D Graphics Library ====================================================== Source ------ This repository lives at https://gitlab.freedesktop.org/mesa/mesa. Other repositories are likely forks, and code found there is not supported. Build & install --------------- You can find more information in our documentation (`docs/install.rst <https://mesa3d.org/install.html>`_), but the recommended way is to use Meson (`docs/meson.rst <https://mesa3d.org/meson.html>`_): .. code-block:: sh $ mkdir build $ cd build $ meson .. $ sudo ninja install Support ------- Many Mesa devs hang on IRC; if you're not sure which channel is appropriate, you should ask your question on `Freenode's #dri-devel <irc://chat.freenode.net#dri-devel>`_, someone will redirect you if necessary. Remember that not everyone is in the same timezone as you, so it might take a while before someone qualified sees your question. To figure out who you're talking to, or which nick to ping for your question, check out `Who's Who on IRC <https://dri.freedesktop.org/wiki/WhosWho/>`_. The next best option is to ask your question in an email to the mailing lists: `mesa-dev\@lists.freedesktop.org <https://lists.freedesktop.org/mailman/listinfo/mesa-dev>`_ Bug reports ----------- If you think something isn't working properly, please file a bug report (`docs/bugs.rst <https://mesa3d.org/bugs.html>`_). Contributing ------------ Contributions are welcome, and step-by-step instructions can be found in our documentation (`docs/submittingpatches.rst <https://mesa3d.org/submittingpatches.html>`_). Note that Mesa uses gitlab for patches submission, review and discussions.