Hi,
> > > So I am guessing the Felix version is lucky there are
> > > no gratuitous temporaries to be saved when this happens,
> > > and the C code is unlucky and there are.
> > >
> > > Maybe someone who knows how the optimiser works can comment?
> >
> > One problem with departing from the ABI eve
On Sat, 2007-10-27 at 12:54 +0200, Richard Guenther wrote:
> On 10/27/07, Robert Dewar <[EMAIL PROTECTED]> wrote:
> > skaller wrote:
> >
> > > So I am guessing the Felix version is lucky there are
> > > no gratuitous temporaries to be saved when this happens,
> > > and the C code is unlucky and th
> If you make the function static then gcc can chose ABI-incompatible
> calling conventions.
Right, and the gain can be significant on x86.
--
Eric Botcazou
On 10/27/07, Robert Dewar <[EMAIL PROTECTED]> wrote:
> skaller wrote:
>
> > So I am guessing the Felix version is lucky there are
> > no gratuitous temporaries to be saved when this happens,
> > and the C code is unlucky and there are.
> >
> > Maybe someone who knows how the optimiser works can com
skaller wrote:
On Fri, 2007-10-26 at 20:26 -0400, Robert Dewar wrote:
skaller wrote:
So I am guessing the Felix version is lucky there are
no gratuitous temporaries to be saved when this happens,
and the C code is unlucky and there are.
Maybe someone who knows how the optimiser works can comm
On Fri, 2007-10-26 at 20:26 -0400, Robert Dewar wrote:
> skaller wrote:
>
> > So I am guessing the Felix version is lucky there are
> > no gratuitous temporaries to be saved when this happens,
> > and the C code is unlucky and there are.
> >
> > Maybe someone who knows how the optimiser works ca
skaller wrote:
So I am guessing the Felix version is lucky there are
no gratuitous temporaries to be saved when this happens,
and the C code is unlucky and there are.
Maybe someone who knows how the optimiser works can comment?
One problem with departing from the ABI even on a local level
lik
I have occasionally examined asm generated by gcc on my amd64,
and it appears gcc is not optimising recursive functions very
well, though I'm not sure.
I find in code like:
int f(int x) { ... f(y) ... }
that gcc generates an extern ABI compliant function f,
which is recursively c
