Ian Romanick
0c089a5c32
When the register allocator decides to spill a value, all reads of that value are filled. This can result in cases where the same value is filled many times in a single block. In those cases, the result of an earlier fill may still be available when a later fill occurs. This optimization replaces the later fill with a move from the result of the earlier fill. v2: Use FIXED_GRF for register overlap tests. Since this is after register allocation, the VGRF values will not tell the whole truth. v3: Use brw_transform_inst. Suggested by Caio. Add brw_scratch_inst::offset instead of storing it as a source. Suggested by Lionel. v4: In intervening spill to the same location also invalidates the value. 🤦 v5: Don't eliminate a fill if its destination partially overlaps the preceeding fill destination. Fixes failures in cooperative matrix CTS. shader-db: Lunar Lake, Meteor Lake, and DG2 had similar results. (Lunar Lake shown) total instructions in shared programs: 17249903 -> 17249653 (<.01%) instructions in affected programs: 35550 -> 35300 (-0.70%) helped: 20 / HURT: 0 total cycles in shared programs: 893092398 -> 893101836 (<.01%) cycles in affected programs: 2501720 -> 2511158 (0.38%) helped: 6 / HURT: 14 total fills in shared programs: 1901 -> 1776 (-6.58%) fills in affected programs: 1757 -> 1632 (-7.11%) helped: 20 / HURT: 0 fossil-db: Lunar Lake, Meteor Lake, and DG2 had similar results. (Lunar Lake shown) Totals: Instrs: 929949528 -> 926770338 (-0.34%) Cycle count: 105126671329 -> 104851299099 (-0.26%); split: -0.28%, +0.02% Fill count: 6520785 -> 5021518 (-22.99%) Totals from 54281 (2.69% of 2018922) affected shaders: Instrs: 239616289 -> 236437099 (-1.33%) Cycle count: 22051883404 -> 21776511174 (-1.25%); split: -1.33%, +0.08% Fill count: 6406295 -> 4907028 (-23.40%) Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/37827>
`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://docs.mesa3d.org/install.html>`_), but the recommended way is to use Meson (`docs/meson.rst <https://docs.mesa3d.org/meson.html>`_): .. code-block:: sh $ meson setup build $ ninja -C build/ $ sudo ninja -C build/ install Support ------- Many Mesa devs hang on IRC; if you're not sure which channel is appropriate, you should ask your question on `OFTC's #dri-devel <irc://irc.oftc.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://docs.mesa3d.org/bugs.html>`_). Contributing ------------ Contributions are welcome, and step-by-step instructions can be found in our documentation (`docs/submittingpatches.rst <https://docs.mesa3d.org/submittingpatches.html>`_). Note that Mesa uses gitlab for patches submission, review and discussions.