[PATCH] fortran/69121 -- Make IEEE_SCALB generic

Joseph Myers joseph@codesourcery.com
Fri Dec 21 20:01:00 GMT 2018

On Fri, 21 Dec 2018, Steve Kargl wrote:

> scalbln(double x, long n)
> {
>         return (scalbn(x, (n > NMAX) ? NMAX : (n < NMIN) ? NMIN : (int)n));
> }
> A search for glibc's libm locates https://tinyurl.com/ybcy8w4t
> which is a bit-twiddling routine.  Not sure it's worth the
> effort.  Joseph Myers might have an opinion.

Such comparisons are needed in the scalbn / scalbln implementations anyway 
to deal with large exponents.  I suppose where there's a suitable scalbln 
implementation, and you don't know if the arguments are within the range 
of int, calling scalbln at least saves code size in the caller and avoids 
duplicating those range checks.

Joseph S. Myers

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