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

AMD R600g LLVM Back-End Is Working A Bit Better

AMD

Published on 11 June 2012 07:20 AM EDT
Written by Michael Larabel in AMD
17 Comments

The R600g LLVM shader compiler back-end that's primarily intended for the Radeon Gallium3D compute support is now working a bit better for graphics support compared to when it was first committed.

Back in April the R600g LLVM compiler was hooked-up as part of AMD's effort to enable OpenCL/GPGPU support within their open-source driver stack. They've been working on the support for months and it was in early December of last year that the R600g LLVM back-end first surfaced. The LLVM back-end hasn't yet been merged in upstream LLVM but is currently living within Mesa and can be built against LLVM 3.1.

The LLVM back-end for the R600 Gallium3D driver currently isn't used or built by default but requires a build-time switch. When the back-end is integrated, the R600g LLVM support can still be toggled at run-time using the R600_LLVM environment variable.

In April after everything was merged I tried out the Radeon Gallium3D LLVM compiler back-end to see how it would work out for graphics. OpenCL is the target of the shader compiler but it could be used for OpenGL's GLSL too. Back in April it was a broken wreck for this graphics support with Xonotic and other games not rendering correctly, etc.

While GLSL on the R600g LLVM back-end hasn't been the primary target, since April the support has improved. This weekend I tested out Mesa Git master with LLVM 3.1 and it's now working much better when the LLVM back-end is enabled. Xonotic shaders now are working correctly, etc. I didn't encounter any visual defects like I saw when trying it out nearly two months ago.

Though if you're hoping for any performance changes, there weren't any major differences spotted in the few tests that I ran. Granted, the tests were just measuring the in-game frame-rates and not the shader compiler time, etc. However, for anyone interested in seeing some Mesa Git benchmarks from a Radeon HD 4890 setup with the LLVM back-end enabled, head on over to OpenBenchmarking.org.


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. NVIDIA GeForce GTX 970 Offers Great Linux Performance
  2. CompuLab Intense-PC2: An Excellent, Fanless, Mini PC Powered By Intel's i7 Haswell
  3. From The Atom 330 To Haswell ULT: Intel Linux Performance Benchmarks
  4. AMD Radeon R9 285 Tonga Performance On Linux
Latest Linux Articles
  1. Ubuntu 14.10 XMir System Compositor Benchmarks
  2. Btrfs RAID HDD Testing On Ubuntu Linux 14.10
  3. Ubuntu 14.10 Linux 32-bit vs. 64-bit Performance
  4. AMD Moves Forward With Unified Linux Driver Strategy, New Kernel Driver
Latest Linux News
  1. Open-Source, Linux Support For Corsair Link Devices Slowly Materializing
  2. Cairo-Dock 3.4 Shows A Lot Of Progress, Works Toward EGL/Wayland Support
  3. Mesa 10.4 Tentatively Planned For Early December
  4. SteamOS Update 145 Brings Compositor, Update Fixes
  5. GStreamer 2014 Conference Videos Posted: Wayland, HTML5, 3D
  6. Nouveau Now Supports DRI3 Without GLAMOR
  7. Features Of The Linux 3.18 Kernel
  8. Debian Now Defaults To Xfce On Non-x86 Desktops
  9. Phoenix Is Trying To Be An Open Version Of Apple's Swift
  10. Linux 3.19 To Have Skylake Graphics, PPGTT Enablement
Latest Forum Discussions
  1. HOPE: The Ease Of Python With The Speed Of C++
  2. Users/Developers Threatening Fork Of Debian GNU/Linux
  3. Ubuntu 16.04 Might Be The Distribution's Last 32-Bit Release
  4. AMD Releases UVD Video Decode Support For R600 GPUs
  5. Proof that strlcpy is un-needed
  6. xbox one tv tuner
  7. Bye bye BSD, Hello Linux: A Sys Admin's Story
  8. Updated and Optimized Ubuntu Free Graphics Drivers