[Cfp-interest] WG14 IEEE 754-C binding meeting minutes 2018/01/09

[Jim Thomas]

We’ll add this to the agenda for tomorrow’s CFP teleconference.

- Jim Thomas

> On Feb 18, 2018, at 3:49 PM, Fred J. Tydeman <tydeman at tybor.com> wrote:
> 
> On Tue, 9 Jan 2018 13:04:35 -0600 Rajan Bhakta wrote:
>> 
>>   Fred: Look through the new functions and see what is missing in Annex 
>> F. - Not done.
> 
> 18661 versus 754
> 
> 18661 has
>  remainder(x, +/-inf) returns x for x not infinite. [Allows x=NaN]
> 754 has
>  remainder(x, inf) is x for finite x. (5.3.1)
>  remainder(x, inf) is exact for finite normal x. (6.1)
>  remainder(subnormal, inf) signals underflow. (6.1)
> 
> 18661 has
>  remainder(+/-0, y) returns +/-0 for y not zero. [Allows y=NaN]
> 754 has
>  r = remainder(x, y) is defined for finite x and y ... (5.3.1)
>  If r = 0, its sign shall be that of x. (5.3.1)
> 
> 18661 has
>  roundeven() "(that is, to the nearest value whose least significant
>  bit 0)."  It should be "least significant integer bit".
> 754 has
>  no such phrase in (5.3.1, 5.9)
> 
> Not sure about min, max, minmag, maxmag, since I am looking at 18661-1
> (2014) and there have been updates to it.
> 
> 18661 has
>  nextup(-HUGE_VAL) is not mentioned.
> 754 has
>  nextup(-inf) if the finite negative number largest in magnitude. (5.3.1)
> 
> 18661 has
>  nextdown(+HUGE_VAL) is not mentioned.
> 754 has
>  nextdown(+inf) is -nextup(-inf) (5.3.1)
> 
> 18661 has
>  canonicalize(SNAN): appears to be missing a domain error in
>  the main body of the standard.
>  Also, for F.10.8.7, canonicalize(SNAN) raises 'invalid'.
> 754 has
>  convertFormat: no mention of SNAN in 5.4.2, but is implied by 6.2
> 
> Not sure about payload related functions as 754 keeps changing.
> 
> 18661
>  Would it be better if fesetexcept() returned the set of flags that
>  were successfully set?
> 754
>  raiseFlags() returns void (5.7.4)
> 
> 18661
>  fetestexceptflag() returns "OR" of two items; I think it should be
>  "AND".  Also the order of the two arguments is switched from 754.
> 754
>  returns a boolean (5.7.4)
> 
> 
> ---
> Fred J. Tydeman        Tydeman Consulting
> tydeman at tybor.com      Testing, numerics, programming
> +1 (702) 608-6093      Vice-chair of PL22.11 (ANSI "C")
> Sample C99+FPCE tests: http://www.tybor.com
> Savers sleep well, investors eat well, spenders work forever.
> 
> _______________________________________________
> Cfp-interest mailing list
> Cfp-interest at oakapple.net
> http://mailman.oakapple.net/mailman/listinfo/cfp-interest