Re: [ros-dev] ping Alex regarding log2() for scheduler

[Royce Mitchell III]

Royce Mitchell III wrote:
>   Magnus Olsen wrote:
> > Hi I have not test run this code. But i think this form maby are
> > faster that v3 of  Royce  Mitchell III code it leave to the compiler
> > to optimze it more or I complete wrong
> > int highest_bit ( unsigned int i )
> > {
> >     int ret = 0;
> >     int n ;
> >     int t;
> >     int x;
> >
> >    for (t = 0; t>3;t++)
> >   {
> >      x = (16 << t);
> >      n = i >> x;
> >     if ( n )  i = n, ret  += x ;
> >   }
> >      return ret + (i>>1);
> > }
> >
> >
> > 
Unfortunately your code is broken in a couple ways, most notably the
code inside the for() statement never executes. When I fix it to work
correctly, it takes almost 3x longer than my code :(