d9a57c85cc
In cases where LOAD_PAYLOAD is provided a pair of contiguous registers as header sources, try to use a single SIMD16 instruction in order to initialize them. This is unlikely to affect the overall cycle count of the shader, since the compressed instruction has twice the issue time, except due to the reduced pressure on the instruction cache. Main motivation is avoiding instruction-count regressions in combination with the following copy propagation improvements, which will allow the SIMD16 g0-1 header setup emitted for framebuffer writes to be copy-propagated into its LOAD_PAYLOAD, leading to the emission of two SIMD8 MOV instructions instead of a single SIMD16 MOV. Reverting this commit on top of the copy propagation changes would lead to the following shader-db regressions on SKL and other platforms: total instructions in shared programs: 14926738 -> 14935415 (0.06%) instructions in affected programs: 1892445 -> 1901122 (0.46%) helped: 0 HURT: 8676 Without the following copy propagation changes this doesn't have any effect on shader-db on Gen7+, because we would typically set up the FB write header with a separate SIMD16 MOV that isn't currently copy-propagated into the LOAD_PAYLOAD, so the individual SIMD8 MOVs result of LOAD_PAYLOAD lowering would get register-coalesced away under normal circumstances. However that wasn't the case for MRF LOAD_PAYLOAD destinations on Gen6 and earlier, because register coalesce only kicks in for GRFs, leaving a number of redundant SIMD8 MOVs lying around. On SNB this leads to the following shader-db improvements: total instructions in shared programs: 10770538 -> 10734681 (-0.33%) instructions in affected programs: 2700655 -> 2664798 (-1.33%) helped: 17791 HURT: 0 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.