On Thu, Nov 17, 2016 at 2:37 AM, Andrew A. <andj2...@gmail.com> wrote: > Hello, > > I'm using Mesa's software renderer for the purposes of regression > testing in our graphics software. We render various scenes, save a > screencap of the framebuffer for each scene, then compare those > framebuffer captures to previously known-good captures. > > Across runs of these tests on the same hardware, the results seem to > be 100% identical. When running the same tests on a different machine, > results are *slightly* different. It's very similar within a small > tolerance, so this is still usable. However, I was hoping for fully > deterministic behavior, even if the hardware is slightly different. > Are there some compile time settings or some code that I can change to > get Mesa's llvmpipe renderer/rasterizer to be fully deterministic in > its output?
You can force the AVX-capable CPU to run in SSE mode. You can do this by setting the environment variable LP_NATIVE_VECTOR_WIDTH=128 > I'm using llvmpipe, and these are the two different CPUs I'm using to > run the tests: > Intel(R) Xeon(R) CPU E3-1275 v3 > Intel(R) Xeon(R) CPU X5650 The former has AVX, while the latter does not. I believe this explains the difference. Cheers, -ilia _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org https://lists.freedesktop.org/mailman/listinfo/mesa-dev
