On Tue, Jun 12, 2001 at 12:45:02PM -0400, Todd Vierling wrote:
> On Tue, 12 Jun 2001, Manuel Bouyer wrote:
> 
> : > 	callout_reset(&scb->xs->xs_callout,
> : > 	    (newtimeout > 3*1000*1000 ?
> : > 		((newtimeout / 1000 + 1) * hz) : (newtimeout * hz) / 1000),
> : > 	    ahc_timeout, scb);
> 
> : The question is whenever the test is really less expansive than the
> : 64bit computation. I think on some platforms it may be more expensive.
> 
> Only on LP64 platforms, really (sparc64, alpha) -- and those could be
> conditionally compiled to use solely 64-bit arithmetic.
> 
> The flip side is that a 64-bit "/ 1000" is a *lot* slower than its 32-bit
> equivalent on ILP32 platforms, particularly those for which even integer
> divide is a library function (sparc v7).

Hum, yes I was only thinking about multiplication, no divide.

Do we have a macro that could be tested to know whenever we're on a 32 or
64bit platform ?

--
Manuel Bouyer, LIP6, Universite Paris VI.           Manuel.Bouyer@lip6.fr
--