[PATCH][benchtests] Accept output arguments to benchmark functions

[Siddhesh Poyarekar]

On Wed, Dec 04, 2013 at 09:55:40AM +0000, Will Newton wrote:
> On 4 December 2013 07:38, Siddhesh Poyarekar <siddhesh@redhat.com> wrote:
> > Hi,
> >
> > This patch adds the ability to accept output arguments to functions
> > being benchmarked, by nesting the argument type in <> in the args
> > directive.  It includes the sincos implementation as an example, where
> > the function would have the following args directive:
> 
> Is there a line missing here?

Ugh, yeah there is.  sincos would have the following args directive:

## args: double:<double *>:<double *>

The above means that sincos takes three arguments of type double,
double * and double *, where the last two arguments (enclosed with <>)
are output arguments.

> 
> It's not clear to me how these values map to the arguments / return values.
> 

The values map only to the input arguments.  So if I had a directive
like this:

## args: int:<int *>:int:<int *>

and I have a value list like this:

1, 2
3, 4
5, 6

then the function calls generated would be:

foo (1, &out1, 2, &out2);
foo (3, &out1, 4, &out2);
foo (5, &out1, 6, &out2);

Siddhesh