8dcf807cb4
The scalar VS backend has never handled float[] and vec2[] outputs
correctly (my original code was broken). Outputs need to be padded
out to vec4 slots.
In fs_visitor::nir_setup_outputs(), we tried to process each vec4 slot
by looping from 0 to ALIGN(type_size_scalar(type), 4) / 4. However,
this is wrong: type_size_scalar() for a float[2] would return 2, or
for vec2[2] it would return 4. This looked like a single slot, even
though in reality each array element would be stored in separate vec4
slots.
Because of this bug, outputs[] and output_components[] would not get
initialized for the second element's VARYING_SLOT, which meant
emit_urb_writes() would skip writing them. Nothing used those values,
and dead code elimination threw a party.
To fix this, we introduce a new type_size_vec4_times_4() function which
pads array elements correctly, but still counts in scalar components,
generating correct indices in store_output intrinsics.
Normally, varying packing avoids this problem by turning varyings into
vec4s. So this doesn't actually fix any Piglit or dEQP tests today.
However, if varying packing is disabled, things would be broken.
Tessellation shaders can't use varying packing, so this fixes various
tcs-input Piglit tests on a branch of mine.
v2: Shorten the implementation of type_size_4x to a single line (caught
by Connor Abbott), and rename it to type_size_vec4_times_4()
(renaming suggested by Jason Ekstrand). Use type_size_vec4
rather than using type_size_vec4_times_4 and then dividing by 4.
Signed-off-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Jason Ekstrand <jason.ekstrand@intel.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.