On Fri, Mar 31, 2023 at 10:46 AM Martin Jambor <mjam...@suse.cz> wrote:
>
> Hi,
>
> we are in the process of changing data structures holding information
> about constants passed by reference and in aggregates to use unsigned
> int offsets rather than HOST_WIDE_INT (which was selected simply
> because that is what fell out of get_ref_base_and_extent at that time)
> in order to conserve memory, especially at WPA time.
>
> PR 109303 testcase discovers that we do not properly check that we
> only create jump functions with offsets (plus sizes) that fit into the
> smaller type. This patch adds the necessary check.
>
> Bootstrapped and tested on x86_64-linux. OK for master?
>
> Thanks,
>
> Martin
>
>
> gcc/ChangeLog:
>
> 2023-03-30 Martin Jambor <mjam...@suse.cz>
>
> PR ipa/109303
> * ipa-prop.cc (determine_known_aggregate_parts): Check that the
> offset + size will be representable in unsigned int.
>
> gcc/testsuite/ChangeLog:
>
> 2023-03-30 Jakub Jelinek <ja...@redhat.com>
> Martin Jambor <mjam...@suse.cz>
>
> PR ipa/109303
> * gcc.dg/pr109303.c: New test.
> ---
> gcc/ipa-prop.cc | 4 +++-
> gcc/testsuite/gcc.dg/pr109303.c | 24 ++++++++++++++++++++++++
> 2 files changed, 27 insertions(+), 1 deletion(-)
> create mode 100644 gcc/testsuite/gcc.dg/pr109303.c
>
> diff --git a/gcc/ipa-prop.cc b/gcc/ipa-prop.cc
> index de45dbccf16..9ffd49b590c 100644
> --- a/gcc/ipa-prop.cc
> +++ b/gcc/ipa-prop.cc
> @@ -2086,7 +2086,9 @@ determine_known_aggregate_parts (struct
> ipa_func_body_info *fbi,
> whether its value is clobbered any other dominating one. */
> if ((content->value.pass_through.formal_id >= 0
> || content->value.pass_through.operand)
> - && !clobber_by_agg_contents_list_p (all_list, content))
> + && !clobber_by_agg_contents_list_p (all_list, content)
> + && (content->offset + content->size - arg_offset
> + <= (HOST_WIDE_INT) UINT_MAX * BITS_PER_UNIT))
> {
it does seem a bit misplaced since after the if we add the same
'content' to another
list anyway. Wouldn't a more obvious place be where we end up truncating
this sum?
> struct ipa_known_agg_contents_list *copy
> = XALLOCA (struct ipa_known_agg_contents_list);
> diff --git a/gcc/testsuite/gcc.dg/pr109303.c b/gcc/testsuite/gcc.dg/pr109303.c
> new file mode 100644
> index 00000000000..f91535991c7
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/pr109303.c
> @@ -0,0 +1,24 @@
> +/* PR ipa/109303 */
> +/* { dg-do compile { target lp64 } } */
> +/* { dg-options "-O2" } */
> +
> +struct __attribute__((packed)) A { char c1; short a1[__INT_MAX__]; };
> +struct __attribute__((packed)) B { char c2; short a2[100]; };
> +struct S { struct A p1; struct B p2[4]; };
> +void bar (short int);
> +
> +static void
> +foo (struct S *q)
> +{
> + for (int i = 0; i < q->p1.c1; i++)
> + for (int j = 0; j < q->p2[i].c2; j++)
> + bar (q->p2[i].a2[j]);
> +}
> +
> +int
> +main ()
> +{
> + struct S q = {};
> + q.p2[0].c2 = q.p2[1].c2 = 3;
> + foo (&q);
> +}
> --
> 2.40.0
>
