Bill Allombert on Thu, 25 Oct 2012 21:02:14 +0200

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Re: forprime in 32bit is 50x slower if p>2^32

On Thu, Oct 25, 2012 at 01:13:39PM -0400, Charles Greathouse wrote:
> > Threshold between an efficient sieve and expensive unextprime()...
> No, even worse: it has to use nextprime(). This means it loops through
> the good congruence classes mod 210 and runs BPSW_psp until it finds a
> hit...

Maybe we could at least replace 210 by something larger.

> I don't have a 32-bit system to test and I expect such systems will be
> less and less popular. Unfortunately without a 64-bit version of
> Cwgwin (?) Windows users are stuck with the 32-bit version. That's a
> pity...

A 64bit version of cygwin would not necessarily help. Indeed we have a 64bit
version of mingw already. What we need is a build environment such that 

> > I would not make it a priority: we have many more projects than we can handle
> > already :-(.
> I feel the same way.

If you had to debug ellheegner in 32bit, you might change your mind.

Beside ARM users are stuck with 32bit for some years still.