Hi Ludovic, On Mon 31 Aug 2009 10:42, l...@gnu.org (Ludovic Courtès) writes:
> Andy Wingo <wi...@pobox.com> writes: > >>> scm_tc7_subr_2o SCM (*) () -- 0 arguments. >>> scm_tc7_subr_1 SCM (*) (SCM) -- 1 argument. >>> scm_tc7_subr_1o SCM (*) (SCM) -- 1 optional argument. >>> scm_tc7_subr_2o SCM (*) (SCM, SCM) -- 2 required args. >>> scm_tc7_subr_2o SCM (*) (SCM, SCM) -- 2 optional args. >>> scm_tc7_subr_3 SCM (*) (SCM, SCM, SCM) -- 3 required args. >>> scm_tc7_lsubr SCM (*) (SCM) -- list subrs >>> scm_tc7_lsubr_2 SCM (*) (SCM, SCM, SCM) >> >> I would like to make these all be gsubrs. There are very few places >> where these constants actually exist in code "out there" -- normally the >> way to do this is to use scm_c_define_gsubr, and it does the right >> thing. >> >> I'll probably do a: >> >> #define scm_tc7_subr_2o \ >> scm_tc7_subr_2o_NO_LONGER_EXISTS_USE_scm_c_define_gsubr >> >> or something like that. > > You can't do that because such subrs are created by `create_gsubr ()' > when the signature allows it. Or did you mean `create_gsubr ()' would > now create only gsubrs? Yes, I mean for create_gsubr to return gsubrs. > These specialized subr types allow for faster dispatch, as opposed to > the argument count checks (and argument copies) that are done in > `scm_i_gsubr_apply ()'. Thus, I think replacing all of them with gsubrs > may have a negative impact performance-wise. That might be true with the current implementation, but it need not be true with dispatch in the VM. The specialized subr types don't actually gain us anything; you can do a gsubr dispatch just as fast, comparing the tc16 instead of the tc7. >>> scm_tc7_dsubr double (*) (double) -- double subrs >> >> I'll remove these, changing their implementations to be gsubrs. This >> only affects $sin et al; I'll probably roll the transcendental versions >> into the subrs as well. > > Yes, it seems to be seldom used. However, it might be a semi-public > API... Undocumented of course. I seriously doubt this removal will cause problems. > Sounds like a nice plan! We'll see how it goes :) This will be on my subr-simplification branch. A -- http://wingolog.org/
