Arlie Davis
daa775b58e
This patch significantly reduces the size of the libGL.so binary. It does not change the (externally visible) behavior of libGL.so at all. gl_gentable.py generates a function, _glapi_create_table_from_handle. This function allocates a large dispatch table, consisting of 1300 or so function pointers, and fills this dispatch table by doing symbol lookups on a given shared library. Previously, gl_gentable.py would generate a single, very large _glapi_create_table_from_handle function, with a short cluster of lines for each entry point (function). The idiom it generates was a NULL check, a call to snprintf, a call to dlsym / GetProcAddress, and then a store into the dispatch table. Since this function processes a large number of entry points, this code is duplicated many times over. We can encode the same information much more compactly, by using a lookup table. The previous total size of _glapi_create_table_from_handle on x64 was 125848 bytes. By using a lookup table, the size of _glapi_create_table_from_handle (and the related lookup tables) is reduced to 10840 bytes. In other words, this enormous function is reduced by 91%. The size of the entire libGL.so binary (measured when stripped) itself drops by 15%. So the purpose of this change is to reduce the binary size, which frees up disk space, memory, etc. size lib/libGL.so.1.2.0 on my system shows (Andreas) text data bss dec hex filename 565947 11256 2720 579923 8d953 lib/libGL.so.1.2.0 before 469211 21848 2720 493779 788d3 lib/libGL.so.1.2.0 after v2: Incorporate Matt's feedback. Reviewed-by: Ian Romanick <ian.d.romanick@intel.com> Reviewed-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com> Tested-by: Jeremy Huddleston Sequoia <jeremyhu@apple.com> Signed-off-by: Andreas Boll <andreas.boll.dev@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.