Hi Joseph, this seems related to your proposal GSoC proposal in the beginning of this year. Do you have any comments about Tejas's idea? Do you think this would be a good (part of) a GSoC project next year?
Thanks a lot, Martin On Sat, Oct 13 2018, Tejas Joshi wrote: > Hello. > I reached asking about GCC GSoC project about adding and > folding functions > like roundeven. I could not apply for the idea this year but > interested in the peoject and > really hoping it would be carry forwarded. Since I've been studying > source code and about the project, I think working on this from now > would give me some heads up and hands on with the source code. > > I did study <http://www.open-std.org/jtc1/sc22/wg14/www/docs/n1778.pdf>. > It does tell that roundeven rounds its argument to nearest integral > ties to even (least significant bit 0) returning integral value > provided that the resulting value is exact. > So, for the start, I'd be implementing this functionality for roundeven. > As ita said in earlier mails that, similar functions like > real_ceil are implemented > in real.c and are used in fold-const-call.c. > Roundeven might be implemented in similar way. Is it built-in > (internal) function means not to be exposed to end-user? > Studying some functions like real_ceil, there are call checks > (flag_errno_math) so I believe similar would be needed for roundeven. > > In real.c where real_ceil is implemented, there are function calls > (and implementations) like do_fix_trunc which also then call functions > like decimal_do_dix_trunc (maybe the main functionality of > do_fix_trunc?, other are just checks, like NaN or qNaN). I did not > understand these functions really and what do they do. Also I did not > understand the structure of REAL_VALUE_TYPE (r->cl and etc?) > > Also when does the real.c and fold-const-call.c comes in picture in > the flow of GCC (Is it for GIMPLE level instruction selection (gimple > stmnt to corresponding rtl instruction))? > Thanks. > > Regards, > -Tejas
