Thanks, Sid!
(one comment below)
Am Donnerstag, dem 26.10.2023 um 07:51 -0400 schrieb Siddhesh Poyarekar:
> On 2023-10-26 04:37, Martin Uecker wrote:
>
> > /* ... and either PARM is void * or has a type that is complete and
> > has a
> > constant size... */
> > && ((typesize && poly_int_tree_p (typesize))
> > @@ -1587,10 +1587,14 @@ parm_object_size (struct object_size_info *osi,
> > tree var)
> > unsigned argpos = 0;
> >
> > /* ... then walk through the parameters to pick the size parameter
> > and
> > - safely scale it by the type size if needed. */
> > + safely scale it by the type size if needed.
> > +
> > + TODO: we could also compute the size of VLAs where the size is
> > + given by a function parameter. */
>
> Isn't this testcase h() in builtin-dynamic-object-size-20.c? If you're
> referring to testcase i(), then maybe "where the size is given by a
> non-trivial function of a function parameter, e.g.
> fn (size_t n, char buf[dummy(n)])."
h() is supported. For i() we would need something as
__builtin_access__with_size to record the result of dummy().
But the comment refers to the simpler case:
fn (size_t n, char (*buf)[n])
[[gnu::access(read_write, 2, 1)]]
This doesn't work because buf[n] does not have constant
size, but it could be made to work more easily because
the size is directly given by a function argument.
Martin
>
> > for (arg = fnargs; arg; arg = TREE_CHAIN (arg), ++argpos)
> > - if (argpos == access->sizarg && INTEGRAL_TYPE_P (TREE_TYPE (arg)))
> > + if (argpos == access->sizarg)
> > {
> > + gcc_assert (INTEGRAL_TYPE_P (TREE_TYPE (arg)));
> > sz = get_or_create_ssa_default_def (cfun, arg);
> > if (sz != NULL_TREE)
> > {
> >
>
> We rely on the frontend to make sure that the arg at sizarg is an
> integral type. OK.
>
> Overall the change looks OK with a few nits I pointed out above.
>
> Thanks,
> Sid
