ldexp and frexp benchmark between Mir, C and Phobos

[Iain Buclaw]

On Fri, 28 Dec 2018 at 20:50, 9il via Digitalmars-d-announce
<digitalmars-d-announce at puremagic.com> wrote:
>
> ldexp and frexp are base building blocks for a lot of math
> functions.
>
> Here is a small benchmark that compares Mir, C and Phobos
> implementations:
>
> https://github.com/libmir/mir-core/blob/master/bench_ldexp_frexp.d
>
> Mir ldexp is 2.5 (5.5 - dmd) times faster for double and float.
>

You could double the speed of ldexp if you actually used the
checkedint compiler intrinsics rather than implementing it yourself.

Using libm's ldexp() is also likely going to be 2-5x slower than using
the implementation you've written for mir.ldexp().  For one, your
version will be inlined!

-- 
Iain