1. Computers
  2. Display Drivers
  3. Graphics Cards
  4. Memory
  5. Motherboards
  6. Processors
  7. Software
  8. Storage
  9. Operating Systems


Facebook RSS Twitter Twitter Google Plus


Phoronix Test Suite

OpenBenchmarking.org

Mesa: Fixed Function Programs Generating GLSL

Mesa

Published on 07 October 2011 06:59 AM EDT
Written by Michael Larabel in Mesa
2 Comments

Last month at XDC2011 Chicago the long-standing goal of killing off Mesa IR was talked about by Intel. There's already been the GLSL-To-TGSI translator (and also competing with that is LunarGLASS to replace Mesa IR with LLVM IR), and now there's some new work to talk about in this area that works towards the common goal.

Eric Anholt has published patches that convert the fixed function fragment program generator for Mesa to output GLSL IR. This is advancing towards the goal of having the drivers accept GLSL IR for code generation and now pushes fixed function fragment programs through the GLSL IR optimization pass. This affects hundreds of lines of code and is expected to provide an improvement for real applications. Here is Anholt's message:
Here's this patch series again, part of the kill-Mesa-IR goal we have for next release. It's been no regressions for me for a while, I was just trying to track down a 2% performance regression on gen6. It turns out that on my gen4 system, it's no performance regression, and on gen7 (at least according to testing with the followon patches to use the new coegen), it's a ~4% performance win.

While many things were learned in the process, the cause of the 2% loss appears to come down to some GPU instruction pipelining issue with lots of handwaving on my part. When using the new backend, we generate like 1/3 fewer instructions (after accounting for the 8/16 compile).

I'm not including the patches for using the new backend quite yet, as there's a functional regression on gm45 in the new backend that I need to track down first.


Mesa 7.12/8.0 is shaping up to be one hell of a release, particularly if OpenGL 3.0 support is achieved.

About The Author
Michael Larabel is the principal author of Phoronix.com and founded the web-site in 2004 with a focus on enriching the Linux hardware experience and being the largest web-site devoted to Linux hardware reviews, particularly for products relevant to Linux gamers and enthusiasts but also commonly reviewing servers/workstations and embedded Linux devices. Michael has written more than 10,000 articles covering the state of Linux hardware support, Linux performance, graphics hardware drivers, and other topics. Michael is also the lead developer of the Phoronix Test Suite, Phoromatic, and OpenBenchmarking.org automated testing software. He can be followed via and or contacted via .
Latest Linux Hardware Reviews
  1. AMD Launches New FX CPUs, Cuts Prices On Existing Processors
  2. Preview: AMD's FX-9590 Eight-Core At Up To 5.0GHz On Linux
  3. Intel Launches The Core i7 5960X, Mighty Powerful Haswell-E CPUs
  4. AMD Radeon R9 290: Gallium3D vs. Catalyst Drivers
Latest Linux Articles
  1. Ondemand vs. Performance CPU Governing For AMD FX CPUs On Linux 3.17
  2. How Intel Graphics On Linux Compare To Open-Source AMD/NVIDIA Drivers
  3. The Fastest NVIDIA GPUs For Open-Source Nouveau With Steam Linux Gaming
  4. Testing For The Latest Linux Kernel Power Regression
Latest Linux News
  1. New Group Calls For Boycotting Systemd
  2. The Features To Find With The Imminent Release Of LLVM/Clang 3.5
  3. Borderlands 2 Is Coming To Linux
  4. The Witcher 2 Ups The Performance More & Works Around Catalyst Bug
  5. Running Gallium3D's LLVMpipe On The Eight-Core 5GHz CPU
  6. Trying Intel OpenCL On Linux For Video Encoding
  7. GSoC 2014 Yielded Some Improvements For Mesa/X.Org This Year
  8. webOS Lives On As LuneOS With New Release
  9. Marek Lands Radeon Gallium3D HyperZ Improvements
  10. Mozilla Firefox 32 Surfaces With HTML5, Developer Changes
Latest Forum Discussions
  1. Lennart Poettering Talks Up His New Linux Vision That Involves Btrfs
  2. nv and xorg.conf under Debian PPC
  3. AMD graphics doesn't work with AMD Catalyst drivers
  4. Best Radeon for a Power Mac G5?
  5. The dangers of Linux kernel development
  6. Updated and Optimized Ubuntu Free Graphics Drivers
  7. AMD Releases UVD Video Decode Support For R600 GPUs
  8. SSD seems slow