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. The MSI X99S SLI PLUS Is Working & Running Well On Linux
  2. NVIDIA GeForce GTX 980: The Best GPU For Linux Gamers
  3. ROCCAT LUA: A Linux-Friendly Gaming Mouse
  4. Cheetah Mounts: The Affordable Way To Put Your TV On The Wall
Latest Linux Articles
  1. Preview: Radeon Gallium3D Performance For CS:GO On Linux
  2. XWayland Linux Gaming Performance With GNOME Wayland On Fedora 21
  3. EXT4/Btrfs/XFS/F2FS Benchmarks On Linux 3.17
  4. Fedora 21 Alpha First Impressions: It's Great
Latest Linux News
  1. VA-API Gallium3D State Tracker Added Back To Mesa
  2. Radeon DRM Gets New Information Ioctl Queries
  3. Mir 0.8 Works On Less ABI Breakage, Touchspots, Responsiveness
  4. CS:GO For Linux Gains Better Stability, Community Server Support
  5. NVIDIA Issues Updated 340.46 Long-Lived Driver Release
  6. KDE Plasma 5.1 Now In Beta
  7. Systemd & Debian Were Most Popular In September
  8. Microsoft Announces... Windows 10 With A Start Menu
  9. Borderlands 2 Launches On Steam For Linux
  10. Debian Jessie Might Get Rid Of The kFreeBSD Port
Latest Forum Discussions
  1. X.Org Is Looking For Some Female Help
  2. Microsoft Announces... Windows 10 With A Start Menu
  3. NVIDIA Alerts Nouveau: They're Starting To Sign/Validate GPU Firmware Images
  4. Updated and Optimized Ubuntu Free Graphics Drivers
  5. Nero CD/DVD Burning Software On Linux Is Dead
  6. New Group Calls For Boycotting Systemd
  7. FSF Issues Statement On Shellshock Bash Vulnerability
  8. X.Org Women Outreach Program Only Turns Up Two Applicants So Far