-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Luca Barbieri wrote: >> If you're working on a driver for a scalar chip, you might want to pull >> brw_fs_channel_expressions and brw_fs_vector_splitting up and get them >> used -- it should make sensible codegen a lot easier for them. > > Current drivers for scalar hardware take Mesa IR/TGSI input and not GLSL IR. > > Using GLSL IR might be interesting, but how do you plan to support > assembly programs? > Will a converter from Mesa IR to GLSL IR be used for that?
Yes. Post-7.9 we have: 1. Run directly from GLSL IR for software (where "directly" almost certainly involves LLVM). 2. Compile assembly shaders to GLSL IR (possibly via Mesa IR -> GLSL IR translation). This will allow support of other NV assembly extensions for free on more advanced GLSL hardware. This will give better support for applications that use Cg. The GLSL backend for Cg generates some ugly, ugly code. 3. Add full support for GLSL 1.30. 4. Geometry shader support. 5. Gut prog_execute and fixed-function *software* TNL. I suspect that #1 and #2 will happen in parallel (I know Ken wants to work on the converter) so that we can have a single backend in the i965 driver. #5 depends on #1 and #2 being complete and accepted. I'm not sure about the ordering of #3 relative to the others, and #4 depends on it. We really want GLSL 1.30 and geometry shaders by the end of the year. We'll see if it happens. > Having two hardware backends, one for GLSL IR, and one for Mesa > IR/TGSI doesn't seem to be a feasible long-term solution, and dropping > assembly program support also isn't (e.g. Doom 3 will stop working). > > Also, would converting GLSL IR to LLVM and writing an hardware LLVM > backend be a better idea? > That gives an instruction matcher, scalarizer and register allocator > for free, plus optionally middle-end optimizations. -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iEYEARECAAYFAkyH3sUACgkQX1gOwKyEAw/adACghnChPV5L95ArCPUO4q83VIqX PAoAnA/L01WMlqh3hpcy69+Hq4IjcYlN =V7Qt -----END PGP SIGNATURE----- _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
