[changing subjects not to derail original discussion] On Fri, Nov 14, 2014 at 12:25 PM, Henri Verbeet <hverb...@gmail.com> wrote: >> I strongly doubt that the performance increases are due >> to better d3d9 bytecode -> TGSI conversion than -> glsl -> tgsi >> conversion -- most serious backends (r600, radeonsi, nouveau) have >> optimizing compilers that should take care of such issues. > > It was just an example, but at least in the past I've seen for example > the translation for D3D cnd and cmp result in pretty sub-optimal code > in r600g. In GLSL 1.30 and up mix() with a bool argument could perhaps > make it easier for the driver to end up with something reasonable. But
I can't speak for the radeon guys, but I know I sure would love to see any reports of poor code being generated by nouveau in response to legitimate-seeming TGSI (or GLSL). In some cases, a simple optimization can be added to take care of it, and I'd definitely appreciate the extra pair of eyeballs on driver-generated code :) The report can be as simple as "here is the TGSI snippet, take a look at how crappy the code it generates is". At least for nouveau, I can feed that directly into a compiler that can target any of the relevant backends. [Note, r600g didn't have an optimizer enabled until ~1y ago; not sure if your analysis was with or without sb.] Cheers, -ilia _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev
