Kenneth Graunke
bf05af3f0e
Consider the case of two nearly identical GLSL fragment shaders:
out vec4 color;
void main() { color = vec4(1); }
and
layout(early_fragment_tests) in;
out vec4 color;
void main() { color = vec4(1); }
These shaders compile to the exact same assembly, but have distinct
values for brw_wm_prog_data::early_fragment_tests.
Since these are two independent GLSL shaders, they have different
program keys - notably, brw_wm_prog_key::program_string_id differs.
When uploading the second, brw_upload_cache will find an existing copy
of the assembly in the cache BO, which means matching_data will be
non-NULL. Although we create a second cache item (with the new key
and prog_data), we set item->offset to the existing copy and avoid
re-uploading duplicate assembly.
However, brw_search_cache() would only flag BRW_NEW_*_PROG_DATA if
item->offset differed from the supplied offset. With reuse, both
programs have the same offset, but prog_data changed. We have to
flag it, but failed to.
To fix this, we simply need to check if the aux (prog_data) pointer
changed. If either the assembly or the prog_data differs, flag it.
This fixes a regression since 1bba29ed40,
where Topi fixed brw_upload_cache() to actually reuse identical
assembly. Prior to that, reuse basically never happened due to bugs.
Unfortunately, this code apparently wasn't prepared to handle reuse!
Fixes GPU hangs in Dolphin on Broadwell.
Huge thanks to Pierre Bourdon and Ilia Mirkin for debugging this
and helping track down the real issue.
Cc: "11.0" <mesa-stable@lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=92623
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Topi Pohjolainen <topi.pohjolainen@intel.com>
Reviewed-by: Kristian Høgsberg <krh@bitplanet.net>
Tested-by: Pierre Bourdon <delroth@gmail.com>
File: docs/README.WIN32 Last updated: 21 June 2013 Quick Start ----- ----- Windows drivers are build with SCons. Makefiles or Visual Studio projects are no longer shipped or supported. Run scons libgl-gdi to build gallium based GDI driver. This will work both with MSVS or Mingw. Windows Drivers ------- ------- At this time, only the gallium GDI driver is known to work. Source code also exists in the tree for other drivers in src/mesa/drivers/windows, but the status of this code is unknown. Recipe ------ Building on windows requires several open-source packages. These are steps that work as of this writing. - install python 2.7 - install scons (latest) - install mingw, flex, and bison - install pywin32 from here: http://www.lfd.uci.edu/~gohlke/pythonlibs get pywin32-218.4.win-amd64-py2.7.exe - install git - download mesa from git see http://www.mesa3d.org/repository.html - run scons General ------- After building, you can copy the above DLL files to a place in your PATH such as $SystemRoot/SYSTEM32. If you don't like putting things in a system directory, place them in the same directory as the executable(s). Be careful about accidentially overwriting files of the same name in the SYSTEM32 directory. The DLL files are built so that the external entry points use the stdcall calling convention. Static LIB files are not built. The LIB files that are built with are the linker import files associated with the DLL files. The si-glu sources are used to build the GLU libs. This was done mainly to get the better tessellator code. If you have a Windows-related build problem or question, please post to the mesa-dev or mesa-users list.