Yevhenii Kolesnikov
9427aaeab7
If loop iterator is incremented with something other than regular addition, it would be more error prone to calculate the number of iterations theoretically. What we can do instead, is try to emulate the loop, and determine the number of iterations empirically. These operations are covered: - imul - fmul - ishl - ishr - ushr Also add unit tests for loop unrollment. Improves performance of Aztec Ruins (sixonix gfxbench5.aztec_ruins_vk_high) by -1.28042% +/- 0.498555% (N=5) on Intel Arc A770. v2 (idr): Rebase on 3 years. :( Use nir_phi_instr_add_src in the test cases. v3 (idr): Use try_eval_const_alu in to evaluate loop termination condition in get_iteration_empirical. Also restructure the loop slightly. This fixed off by one iteration errors in "inverted" loop tests (e.g., nir_loop_analyze_test.ushr_ieq_known_count_invert_31). v4 (idr): Use try_eval_const_alu in to evaluate induction variable update in get_iteration_empirical. This fixes non-commutative update operations (e.g., shifts) when the induction varible is not the first source. This fixes the unit test nir_loop_analyze_test.ishl_rev_ieq_infinite_loop_unknown_count. v5 (idr): Fix _type parameter for fadd and fadd_rev loop unroll tests. Hopefully that fixes the failure on s390x. Temporarily disable fmul. This works-around the revealed problem in glsl-fs-loop-unroll-mul-fp64, and there were no shader-db or fossil-db changes. v6 (idr): Plumb max_unroll_iterations into get_iteration_empirical. I was going to do this, but I forgot. Suggested by Tim. v7 (idr): Disable fadd tests on s390x. They fail because S390 is weird. Almost all of the shaders affected (OpenGL or Vulkan) are from gfxbench or geekbench. A couple shaders in Deus Ex (OpenGL), Dirt Rally (OpenGL), Octopath Traveler (Vulkan), and Rise of the Tomb Raider (Vulkan) are helped. The lost / gained shaders in OpenGL are an Aztec Ruins shader that goes from SIMD16 to SIMD8. The spills / fills affected are in a single Aztec Ruins (Vulkan) compute shader. shader-db results: Skylake, Ice Lake, and Tiger Lake had similar results. (Tiger Lake shown) total loops in shared programs: 5514 -> 5470 (-0.80%) loops in affected programs: 62 -> 18 (-70.97%) helped: 37 / HURT: 0 LOST: 2 GAINED: 2 Haswell and Broadwell had similar results. (Broadwell shown) total loops in shared programs: 5346 -> 5298 (-0.90%) loops in affected programs: 66 -> 18 (-72.73%) helped: 39 / HURT: 0 fossil-db results: Skylake, Ice Lake, and Tiger Lake had similar results. (Tiger Lake shown) Instructions in all programs: 157374679 -> 157397421 (+0.0%) Instructions hurt: 28 SENDs in all programs: 7463800 -> 7467639 (+0.1%) SENDs hurt: 28 Loops in all programs: 38980 -> 38950 (-0.1%) Loops helped: 28 Cycles in all programs: 7559486451 -> 7557455384 (-0.0%) Cycles helped: 28 Spills in all programs: 11405 -> 11403 (-0.0%) Spills helped: 1 Fills in all programs: 19578 -> 19588 (+0.1%) Fills hurt: 1 Lost: 1 Signed-off-by: Yevhenii Kolesnikov <yevhenii.kolesnikov@globallogic.com> Reviewed-by: Timothy Arceri <tarceri@itsqueeze.com> Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/3445>
`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.