This is the mail archive of the
gcc@gcc.gnu.org
mailing list for the GCC project.
Re: mainline performance regression (observered on SPARC)
On Fri, May 24, 2002 at 01:53:33PM -0700, Dan Nicolaescu wrote:
> Andrey Petrov <petrov@netbsd.org> writes:
>
> > On Fri, May 24, 2002 at 11:36:48AM -0700, Dan Nicolaescu wrote:
> > >
> > > Any idea what is the cause of this?
> > >
> > > The code is kind of silly, it moves stuff around between the integer
> > > and fp registers, probably an artifact of the SPARC calling
> > > conventions (passing doubles in the integer registers). But shouldn't
> > > inlining get rid of this?
> > >
> >
> > This made me re-read sparc v9 abi, and it says that floating-point
> > arguments and return values are passed in fpu registers. But some
> > of the fpu registers are volatile across functions calls and some
> > are not. I guess that you see saving/restoring of non-volatile fpu
> > regs.
>
> -mcpu=ultrasparc is v8plus not v9
Then disregard what I just wrote as off-topic.