Re: About GSOC.

[Martin Jambor <mjambor@suse.cz>]

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