284b563fb0
fs_visitor::set_gs_stream_control_data_bits generates some code like "control_data_bits | stream_id << ((2 * (vertex_count - 1)) % 32)" as part of EmitVertex. The first time this (dynamically) occurs in the shader, control_data_bits is zero. Many times we can determine this statically and various optimizations will collaborate to make one of the OR operands literal zero. Converting the OR to a MOV usually allows it to be copy-propagated away. However, this does not happen in at least some shaders (in the assembly output of shaders/closed/UnrealEngine4/EffectsCaveDemo/301.shader_test, search for shl). All of the affected shaders are geometry shaders. Broadwell and Skylake had similar results. (Skylake shown) total instructions in shared programs: 14375452 -> 14375413 (<.01%) instructions in affected programs: 6422 -> 6383 (-0.61%) helped: 39 HURT: 0 helped stats (abs) min: 1 max: 1 x̄: 1.00 x̃: 1 helped stats (rel) min: 0.14% max: 2.56% x̄: 1.91% x̃: 2.56% 95% mean confidence interval for instructions value: -1.00 -1.00 95% mean confidence interval for instructions %-change: -2.26% -1.57% Instructions are helped. total cycles in shared programs: 531981179 -> 531980555 (<.01%) cycles in affected programs: 27493 -> 26869 (-2.27%) helped: 39 HURT: 0 helped stats (abs) min: 16 max: 16 x̄: 16.00 x̃: 16 helped stats (rel) min: 0.60% max: 7.92% x̄: 5.94% x̃: 7.92% 95% mean confidence interval for cycles value: -16.00 -16.00 95% mean confidence interval for cycles %-change: -6.98% -4.90% Cycles are helped. No changes on earlier platforms. Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
`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 status
------------
Travis:
.. image:: https://travis-ci.org/mesa3d/mesa.svg?branch=master
:target: https://travis-ci.org/mesa3d/mesa
Appveyor:
.. image:: https://img.shields.io/appveyor/ci/mesa3d/mesa.svg
:target: https://ci.appveyor.com/project/mesa3d/mesa
Coverity:
.. image:: https://scan.coverity.com/projects/139/badge.svg?flat=1
:target: https://scan.coverity.com/projects/mesa
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 email mailing-lists for patches submission, review and
discussions.