Re: Profiling Ada binaries

[rieachus@comcast.net]

On Monday, July 25, 2016 at 1:14:06 PM UTC-4, Simon Wright wrote:
> rieachus@comcast.net writes:
> 
> > Seriously, the math libraries are written with ease of understanding
> > in mind.
> 
> Like the rest of GNAT, then.

Actually, I was thinking of the original Generic Elementary Functions package and the other standard generic math packages.  These were the result of work for about a decade of NUMWG and were printed, not just packages specifications but bodies as well as special issues of Ada Letters.  Along the way the best algorithms known for many of the functions (in terms of least significant bit--lsb--errors) were improved several times.  And of course, the IEEE Floating Point standards were being improved at the same time, by some of the same people.

There is a lot to be said for using the (hardware) built-in GEF, and as I said, GNAT does let you get at the 32 and 64 bit IEEE floating point hardware.  You may not know that it is possible to access (still) the 80-bit IEEE Extended in x86 (or should that be x87 ;-) compatible CPUs, but not in 64-bit mode.  DEC VAXes had their own floating point formats including decent 128-bit versions. and so on.  Unless you do things like Mandelbrot or Julia sets, work with eigenvectors of large matrices, FFTs, or solve large linear programming problems, double precision is quite enough.