Jason Ekstrand
bb99a58e77
There can be problems with floats and conditional modifiers when copy-propagating a negated UD source. The problem arises when a source modifier is applied to a UD value. In this case, a 33-bit representation is internally used. If you do the following: 1: mov foo:UD 7U 2: mov bar:UD -foo:UD 3: mov out:F bar:UD the out register will have the value (float)(unt32_t)-7 which is some very large floating-point number. However, if we allow copy-propagation of the second mov, we get 1: mov foo:UD 7U 3: mov out:f -bar:UD and, since the negation is computed in 33-bits, we get a value of -7.0f which is clearly not the same. This is a similar problem if the instruction has a conditional modifier where the 33-bit value is used in the comparison and not the 32-bit version. Previously, we checked the source to be copied for the negate and then checked the source being propagated to for the type. This isn't quite what we want because we are really just looking for negated UD sources. A check later in the file ensures that both ends of the propagate have the right type so it works. However, if we relax the restriction that both ends of the propagation have the same type, it ends up causing us to bail early in cases we don't want. Signed-off-by: Jason Ekstrand <jason.ekstrand@intel.com> Reviewed-by: Anuj Phogat <anuj.phogat@gmail.com> Reviewed-by: Matt Turner <mattst88@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.