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

R600 LLVM Back-End Gets Indirect Addressing Support

Mesa

Published on 22 January 2013 05:33 PM EST
Written by Michael Larabel in Mesa
4 Comments

The open-source Radeon R600 LLVM back-end has finally received support for indirect memory addressing.

AMD's Tom Stellard put out the 1200 line patch today that enables indirect addressing support within the R600 LLVM GPU target. Indirect addressing support has been one of the major limitations so far in this Radeon LLVM back-end. This back-end can be optionally used by the R600 Gallium3D driver for its shader compiler and is a key requirement for the Radeon OpenCL/GPGPU compute support. As far as end-users are concerned, the lack of indirect addressing support has made the LLVM back-end shader compiler not work for some OpenGL games like Unigine and Sauerbraten. (See Trying Out AMD's Radeon Gallium3D LLVM Compiler.)

Stellard writes in his mailing list message that for now this indirect addressing is R600-only with the Radeon HD 7000 "Southern islands" implementation still missing a few callbacks used during this process. He additionally writes, "At the moment R600 only supports array sizes of 16 dwords or less. Register packing of vector types is currently disabled, which means that a vec4 is stored in T0_X, T1_X, T2_X, T3_X, rather than T0_XYZW. In order to correctly pack registers in all cases, we will need to implement an analysis pass for R600 that determines the correct vector width for each array."

The R600 LLVM GPU back-end was removed from Mesa and merged into upstream LLVM. This R600 LLVM indirect addressing support will soon likely be merged into Tom Stellard's R600 LLVM repository followed by eventually making it into the next R600 GPU LLVM pull that should end up being released as part of LLVM 3.3 later this year.

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. Intel Pentium G3258 On Linux
  2. SilverStone Precision PS10
  3. ASRock Z97 Extreme6
  4. Nouveau Re-Clocking Is Way Faster, Shows Much Progress For Open-Source NVIDIA
Latest Linux Articles
  1. X.Org Server 1.16 Officially Released With Terrific Features
  2. Ubuntu With Linux 3.16 Smashes OS X 10.9.4 On The MacBook Air
  3. Preview: Benchmarking CentOS 7.0 & Scientific Linux 7.0
  4. Linux 3.16 File-System Tests On A Hard Drive
Latest Linux News
  1. Raspberry Pi B+ ARM Debian Benchmarks
  2. Mozilla Unleashes Firefox 31 Web Browser
  3. GCC 5.0 Is Expected Next Year
  4. PHP5's Successor Might Be PHP7
  5. AMD "Hawaii" Open-Source GPU Acceleration Still Not Working Right
  6. AMDKFD Driver Still Evolving For Open-Source HSA On Linux
  7. GStreamer 1.4.0 Released; OpenGL Improvements, New Features
  8. New Intel GLAMOR Code Is Taking Shape & Running Fast
  9. LLVM 3.5 Gets A Tentative Release Date
  10. EFF Aims To Launch An Open Wireless Router
Latest Forum Discussions
  1. AMD "Hawaii" Open-Source GPU Acceleration Still Not Working Right
  2. Next-Gen OpenGL To Be Announced Next Month
  3. Ubuntu With Linux 3.16 Smashes OS X 10.9.4 On The MacBook Air
  4. Updated and Optimized Ubuntu Free Graphics Drivers
  5. AMD Publishes Open-Source Linux HSA Kernel Driver
  6. KDE Plasma 5 Officially Released
  7. Vote For GOG To Make Galaxy Open Source
  8. TSC Problem on Gigabyte GA-X79-UP4 (rev 1.1)