Google Summer of Code 2018: Call for mentors and ideas

[Martin Jambor]

Hi Joseph,

On Wed, Jan 17 2018, Joseph Myers wrote:
> On Wed, 17 Jan 2018, Martin Jambor wrote:
>
>> 3?) Joseph Myers brought up idea to do "built-in functions for TS 18661
>>     floating-point functions - which has the feature that there are a
>>     lot of similar built-in functions for C99/C11 functions to serve as
>>     a guide for how to implement things)" ...Joseph, would you be
>>     willing to mentor it?
>
> Yes, provided at least one other mentor is available as well as I may not 
> be around all the time during the GSoC period, including one of the 
> evaluation periods.

Thank you (but please think who that other mentor could be :-)

>
> (The outline I put on the wiki page is:
>
>   GCC supports built-in functions for math.h and complex.h functions in 
>   the C99/C11 standards (both folding calls for constant arguments, and 
>   expanding inline when the processor supports appropriate functionality). 
>   More such functions have been added in ISO/IEC TS 18661, supporting 
>   features of IEEE 754-2008. It would be useful to have built-in functions 
>   for those, both folding for constant arguments, and expanding inline 
>   where appropriate (e.g. for roundeven and the functions rounding result 
>   to narrower type, on some processors; roundeven can be inlined on x86 
>   for SSE4.1 and later, and the narrowing functions on IA64 and POWER8, 
>   for example). Existing built-in functions would provide a guide for how 
>   to do this.
>
> This project has the feature that there are lots of smaller subprojects 
> each of which would be a useful enhancement to GCC, so a student could 
> start off with e.g. roundeven built-in functions, closely following how 
> existing code handles round / floor / ceil / trunc, before going on to 
> more complicated functions such as the narrowing ones or the fromfp 
> functions - with scope for functions from TS 18661-3 and TS 18661-4 if 
> they run out of useful functions from TS 18661-1.  If a student were 
> interested I could provide more detailed lists of possible subprojects.)

That is a very nice feature indeed,

Martin