Re: [ros-dev] [ros-diffs] [tkreuzer] 44464: [RTL] Rewrite the rtl bitmap implementation. The old one was a little .... suboptimal. The new one should outperform the old one by several orders of magnitude, especially RtlFindClearBits that was literally searching bit by bit.

[Alex Ionescu]

Well why this then? They should be intrinsics...

On 2009-12-07, at 8:43 PM, Timo Kreuzer wrote:
> > > +unsigned char BitScanForward(ULONG * Index, unsigned long Mask)
> > > +{
> > > *Index = 0;
> > > while (Mask && ((Mask & 1) == 0))
> > > {
> > >    Mask >>= 1;
> > >    ++(*Index);
> > > }
> > > return Mask ? 1 : 0;
> > >
> > > +}
> > >
> > > +unsigned char BitScanReverse(ULONG * const Index, unsigned long Mask)
> > > +{
> > > *Index = 0;
> > > while (Mask && ((Mask & (1 << 31)) == 0))
> > > {
> > >    Mask <<= 1;
> > >    ++(*Index);
> > > }
> > > return Mask ? 1 : 0;
> > >
> > > +}

Best regards,
Alex Ionescu