927a24db14
Each block is processed separately. VGRF channels that are allocated to values that are only used in a particular block are made available in other blocks. This is almost always an improvement, but there are some pessimal cases where it goes horribly wrong. Imagine a shader with two blocks. In that shader, the first block has 5 constants used in the first block and the second block. Three other constants are only used in the first block. The second block has 15 constants that are used only in the block. The static VGRF usage is 3 regardless of packing. However, scheduling may be able to shorten the live range of the first VGRF when it only has values that came from the first block (because three of the values are dead on entry to the second block). This used to occurs in a Mad Max shader on Broadwell. That shader went from 0:0 spills:fills to 107:52. Some changes over the last year, I'm assuming !13734, have prevented this case from occuring. This change created a lot of churn on Haswell and Ivy Bridge. This seems to be primarily due to all the extra constants used for coissue, but I did not investigate very deeply. On older platforms, there were no changes to spills or fills. As a result, this is only used on Broadwell and newer platforms. v2: Update expected checksum for pixmark-piano-v2.trace on gl-zink-anv-tgl. See #9714 for more details. shader-db results: Tiger Lake total instructions in shared programs: 21101332 -> 21102084 (<.01%) instructions in affected programs: 863686 -> 864438 (0.09%) helped: 463 / HURT: 437 total cycles in shared programs: 790573225 -> 790664391 (0.01%) cycles in affected programs: 92546803 -> 92637969 (0.10%) helped: 558 / HURT: 629 total spills in shared programs: 3959 -> 3951 (-0.20%) spills in affected programs: 184 -> 176 (-4.35%) helped: 2 / HURT: 0 total fills in shared programs: 2639 -> 2631 (-0.30%) fills in affected programs: 184 -> 176 (-4.35%) helped: 2 / HURT: 0 LOST: 1 GAINED: 5 Ice Lake and Skylake had similar results. (Ice Lake shown) total instructions in shared programs: 19945216 -> 19944711 (<.01%) instructions in affected programs: 139569 -> 139064 (-0.36%) helped: 66 / HURT: 3 total cycles in shared programs: 858410082 -> 857381323 (-0.12%) cycles in affected programs: 383825958 -> 382797199 (-0.27%) helped: 1012 / HURT: 1055 total spills in shared programs: 6190 -> 6116 (-1.20%) spills in affected programs: 891 -> 817 (-8.31%) helped: 66 / HURT: 3 total fills in shared programs: 7382 -> 7238 (-1.95%) fills in affected programs: 1538 -> 1394 (-9.36%) helped: 66 / HURT: 3 LOST: 5 GAINED: 8 Broadwell total instructions in shared programs: 17820886 -> 17812515 (-0.05%) instructions in affected programs: 800512 -> 792141 (-1.05%) helped: 385 / HURT: 1 total cycles in shared programs: 904482935 -> 903102070 (-0.15%) cycles in affected programs: 422427015 -> 421046150 (-0.33%) helped: 1091 / HURT: 812 total spills in shared programs: 17908 -> 16576 (-7.44%) spills in affected programs: 9459 -> 8127 (-14.08%) helped: 386 / HURT: 0 total fills in shared programs: 25397 -> 22354 (-11.98%) fills in affected programs: 15504 -> 12461 (-19.63%) helped: 385 / HURT: 1 LOST: 2 GAINED: 2 No shader-db changes on Haswell or older platforms. fossil-db results: Tiger Lake Instructions in all programs: 156881463 -> 156890970 (+0.0%) Instructions helped: 9033 Instructions hurt: 10285 Cycles in all programs: 7532597466 -> 7529647924 (-0.0%) Cycles helped: 10548 Cycles hurt: 13667 Spills in all programs: 5490 -> 5110 (-6.9%) Spills helped: 100 Spills hurt: 3 Fills in all programs: 6123 -> 5752 (-6.1%) Fills helped: 100 Fills hurt: 3 Gained: 17 Lost: 47 Ice Lake Instructions in all programs: 141309644 -> 141309603 (-0.0%) Instructions helped: 9 Instructions hurt: 4 Cycles in all programs: 9095812690 -> 9097008049 (+0.0%) Cycles helped: 14288 Cycles hurt: 16381 Spills in all programs: 7418 -> 7404 (-0.2%) Spills helped: 9 Spills hurt: 4 Fills in all programs: 8326 -> 8321 (-0.1%) Fills helped: 9 Fills hurt: 4 Skylake Instructions in all programs: 131872347 -> 131870690 (-0.0%) Instructions helped: 111 Instructions hurt: 3 Cycles in all programs: 8800835649 -> 8802483884 (+0.0%) Cycles helped: 9415 Cycles hurt: 9678 Spills in all programs: 6917 -> 6476 (-6.4%) Spills helped: 111 Spills hurt: 3 Fills in all programs: 7584 -> 7354 (-3.0%) Fills helped: 111 Fills hurt: 3 Lost: 5 Tested-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/7698>
`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 `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://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.