Re: [Qemu-devel] [PATCH 06/27] Correct ppc popcntb logic, implement popcntw and popcntd

[David Gibson]

On Fri, Apr 01, 2011 at 08:02:24PM +0200, Alexander Graf wrote:
> On 01.04.2011, at 19:58, Aurelien Jarno wrote:
> > On Fri, Apr 01, 2011 at 03:15:13PM +1100, David Gibson wrote:
[snip]
> >> +target_ulong helper_popcntd (target_ulong val)
> >> +{
> >> +    val = (val & 0x5555555555555555ULL) + ((val >>  1) &
> >> +                                           0x5555555555555555ULL);
> >> +    val = (val & 0x3333333333333333ULL) + ((val >>  2) &
> >> +                                           0x3333333333333333ULL);
> >> +    val = (val & 0x0f0f0f0f0f0f0f0fULL) + ((val >>  4) &
> >> +                                           0x0f0f0f0f0f0f0f0fULL);
> >> +    val = (val & 0x00ff00ff00ff00ffULL) + ((val >>  8) &
> >> +                                           0x00ff00ff00ff00ffULL);
> >> +    val = (val & 0x0000ffff0000ffffULL) + ((val >> 16) &
> >> +                                           0x0000ffff0000ffffULL);
> >> +    val = (val & 0x00000000ffffffffULL) + ((val >> 32) &
> >> +                                           0x00000000ffffffffULL);
> >> +    return val;
> >> +}
> > 
> > I probably arrive a bit late, but note that for this one you can use
> > ctpop64() (from host-utils.h), which also uses a GCC builtin when
> > available.
> 
> Ah, nice. David - sounds like a good chance for a follow-up patch :)

Done.  I'll send it when I next send a batch for merging.

-- 
David Gibson                    | I'll have my music baroque, and my code
david AT gibson.dropbear.id.au  | minimalist, thank you.  NOT _the_ _other_
                                | _way_ _around_!
http://www.ozlabs.org/~dgibson