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. Scythe Mugen MAX
  2. Intel Core i7 5960X Haswell-E On Linux
  3. Intel 80GB 530 Series M.2 SSD On Linux
  4. With A New Motherboard, The Core i7 5960X Haswell-E Lights Up
Latest Linux Articles
  1. RadeonSI GLAMOR Benchmarks With X.Org Server 1.16
  2. RadeonSI Gallium3D vs. Catalyst At 4K UHD On Linux
  3. MSAA RadeonSI Gallium3D Performance Preview
  4. Intel Core i7 5960X CPU Core Scaling Under Linux
Latest Linux News
  1. SNA & UXA Intel Benchmarks With X.Org Server 1.16
  2. Graphics Driver Changes Coming In The Linux 3.18 Kernel
  3. Tropico 5 Being Released For Linux Gamers This Week
  4. Eclipse IDE Starts Firing Up On Wayland's Weston
  5. OpenSUSE Announcement On SUSE's Recent Merger
  6. Valve Begins Publicly Tracking AMD Catalyst Linux Issues
  7. Digia Qt Spinoff Is Called "The Qt Company"
  8. GNOME 3.14 Makes More Progress In Running Natively On Wayland
  9. Minix 3.3 Released With Cortex-A8 ARM Support, NetBSD Userland Compatibility
  10. More Intel DRM Changes Queued For Linux 3.18, Including Old i830M Fixes
Latest Forum Discussions
  1. Stop grabbing my keyboard :(
  2. New Group Calls For Boycotting Systemd
  3. Best Radeon for a Power Mac G5?
  4. Updated and Optimized Ubuntu Free Graphics Drivers
  5. New stress testing utility for GPU's
  6. Hd 6850
  7. support for first generation UVD blocks (RV6xx, RS780, RS880 and RV790)
  8. Nvidia joins the ranks of Apple and Microsoft