Redundant instructions in loop optimization for x86-64?

[H. J. Lu]

On Fri, Sep 10, 2004 at 11:50:23AM +0200, Jan Hubicka wrote:
> > It seems that gcc 3.4 and 4.0 generate redundant instructions in loop
> > optimization for x86-64:
> > 
> > http://gcc.gnu.org/bugzilla/show_bug.cgi?id=17387
> > 
> > Does anyone know why?
> 
> It is a zero extension GCC believe to be essential.

Is there a way to tell gcc that 32bit zero extension isn't needed for
x86-64?


H.J.