Yes, if we change the representation, we should keep backwards compatability in tgsi text parsing
Jose ----- Original Message ----- > There are some TGSI shaders parsed by tgsi_text_translate which > declare floating-point immediates. Any incompatible change to the > parser would break them. > > Marek > > On Wed, Aug 28, 2013 at 3:57 PM, Jose Fonseca <jfons...@vmware.com> wrote: > > ----- Original Message ----- > >> On Wed, Aug 28, 2013 at 3:32 PM, Dave Airlie <airl...@gmail.com> wrote: > >> >>> IMM[0] FLT32 { 0x...., 0x...., 0x...., 0x.... } # 1.0, 3.0, 2.0, 4.0 > >> >> > >> >> If you use "%.9g" instead of "%.4f" then floating point numbers will be > >> >> preserved without loss of precision. > >> >> > >> > > >> > I see a -nan in my tests that doesn't get reparsed so I expect hex is > >> > still better. > >> > > >> > > >> > oops to list as well this time, sorry. > >> > >> Just in case you are wondering its > >> tests/shaders/glsl-const-builtin-inversesqrt.shader_test and > >> tests/shaders/glsl-const-builtin-normalize.shader_test > >> that throw up the -nan in the dumps. > > > > We could teach tgsi_parse to understand `nan` too. > > > > We could also have a new tgsi_compare() function that, instead of doing a > > bare memcmp, it would scan the tokens, and account for the ambiguity of > > NaNs in IMM FLT32. > > > > > > I just feel a bit awkward that we have `IMM[x] INT32 {...}` and `IMM[x] > > FLT32 {...}` but end up dumping floats as integers. The whole point of > > INT32/FLT32 is to allow humans to read the numbers, because it is just > > syntactic sugar: by definition a shader must behave precisely the same way > > regardless the IMMS have INT32 or FLT32, as in TGSI the type is not > > defined by the arguments but rather the opcodes. > > > > Also, editing IMM FLT32 by hand will be much harder -- you'll need to > > convert floats their integer repreentation, as the floats in the comment > > will likely be ignored.. > > > > > > To me, it seems that would be trading off a concrete advantage -- the > > usability of the TGSI textual representation --, for this much more > > dubious advantage of perfect bit-by-bit reversibility of TGSI > > binary<->text shaders. > > > > > > That said, I don't feel strongly either way. > > > > > > Jose > > _______________________________________________ > > mesa-dev mailing list > > mesa-dev@lists.freedesktop.org > > http://lists.freedesktop.org/mailman/listinfo/mesa-dev > _______________________________________________ mesa-dev mailing list mesa-dev@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/mesa-dev