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. Btrfs On 4 x Intel SSDs In RAID 0/1/5/6/10
  2. AMD Radeon R9 290 On Ubuntu 14.10: RadeonSI Gallium3D vs. Catalyst
  3. MSI X99S SLI PLUS On Linux
  4. NVIDIA GeForce GTX 970 Offers Great Linux Performance
Latest Linux Articles
  1. NVIDIA's Linux Driver Can Deliver Better OpenGL Performance Than Windows 8.1
  2. Windows 8.1 vs. Ubuntu 14.10 With Intel HD Graphics
  3. 6-Way Ubuntu 14.10 Radeon Gallium3D vs. Catalyst Driver Comparison
  4. NVIDIA vs. Nouveau Drivers On Ubuntu 14.10
Latest Linux News
  1. AMD On Linux & Systemd Were Very Popular This Month
  2. Wine 1.7.30 Continues Work On DirectWrite & Offers Regedit Fixes
  3. Has The Sky Fallen? Qualcomm Contributes To Freedreno's DRM/KMS Driver
  4. Manjaro Works To Make Calamares A Distribution-Independent Installer
  5. DisplayLink USB 3.0 Support Sounds Like A Mess
  6. PulseAudio Gains A Native Bluetooth Headset Backend
  7. X.Org Foundation Decides On Its Women Outreach Project
  8. GTK+ 3.16's New GtkGLArea Widget Gets Improved
  9. X.Org Server 1.17 ABI Bumped
  10. Fedora 21 Beta To Be Released Next Week
Latest Forum Discussions
  1. Civilization: Beyond Earth Overcoming Linux GPU Driver Problems
  2. How to get rid of Linux
  3. Step by Step install of Latest Nvidia Driver Article Request
  4. Closed source to opensource
  5. What Would You Like To See Next?
  6. Is foolish currently develop in machine code, hexadecimal and assembly?
  7. Reducing The CPU Usage In Mesa To Improve Performance
  8. Help diagnosing problems with a Readon HD 4670 on Mesa 10.3.2-1