Re: [patch] use __builtin_ctzl in ggc-page

[Richard Earnshaw <rearnsha at gcc dot gnu dot org>]

On Mon, 2005-01-17 at 12:59, Steven Bosscher wrote:
> On Jan 17, 2005 01:38 PM, Richard Earnshaw <rearnsha@gcc.gnu.org> wrote:

> > I'm not convinced these micro-optimizations are such a good thing. 
> > Apart from anything else, they clutter the code unnecessarily
> 
> Well, I think we should use all the builtins we can where it
> makes sense.  It gives you testing of your own builtins and it
> allows you to get the best code for each target.  In this case
> it gives a small (but measurable) speedup for ppc at -O0 for me.

If we are going to start using builtins like this, then they should be
called via macros, not used explicitly in the body of the code.  That
way all the ifdef cludging does not confuse the meaning of the
algorithm.

R.