591f146fd2
The liveness calculation done by the local CSE pass in order to prune AEB entries whose sources are no longer live is currently inaccurate, because the live intervals are calculated once at the beginning of the pass, so they don't take into account any of the copy instructions inserted by the CSE pass as it makes progress. However the IP counter used in that calculation is based on the start_ip of the basic block, which is updated automatically whenever any instructions are inserted into the CFG. This causes the IP counter and liveness intervals to get out of sync in programs with multiple basic blocks, causing the CSE pass to toss AEB entries prematurely, which can lead to missed optimization opportunities rather non-deterministically. On BDW this leads to the following shader-db changes: total instructions in shared programs: 14952488 -> 14951763 (-0.00%) instructions in affected programs: 45416 -> 44691 (-1.60%) helped: 40 HURT: 4 total spills in shared programs: 20989 -> 20970 (-0.09%) spills in affected programs: 103 -> 84 (-18.45%) helped: 3 HURT: 0 total fills in shared programs: 24981 -> 24926 (-0.22%) fills in affected programs: 127 -> 72 (-43.31%) helped: 3 HURT: 0 In addition it avoids a number of regressions in combination with some of the optimization changes I'm working on for SIMD32, which would have made CSE more effective... Causing it to be less effective elsewhere in the program astonishingly. Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
`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.html <https://mesa3d.org/install.html>`_), but the recommended way is to use Meson (`docs/meson.html <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.html <https://mesa3d.org/bugs.html>`_). Contributing ------------ Contributions are welcome, and step-by-step instructions can be found in our documentation (`docs/submittingpatches.html <https://mesa3d.org/submittingpatches.html>`_). Note that Mesa uses gitlab for patches submission, review and discussions.