> Am 30.01.2024 um 03:31 schrieb Alexandre Oliva <ol...@adacore.com>:
>
>
> Variant type copies can't have their own alias sets any more, and it's
> not like setting them affected the pointed-to objects anyway.
>
> Regstrapped on x86_64-linux-gnu; also bootstrapped with -fstrub=internal
> enabled by default. Ok to install?
Ok
Richard
> for gcc/ChangeLog
>
> PR debug/113394
> * ipa-strub.cc (build_ref_type_for): Drop nonaliased. Adjust
> caller.
>
> for gcc/testsuite/ChangeLog
>
> PR debug/113394
> * gcc.dg/strub-internal-pr113394.c: New.
> ---
> gcc/ipa-strub.cc | 31 ++++--------------------
> gcc/testsuite/gcc.dg/strub-internal-pr113394.c | 6 +++++
> 2 files changed, 11 insertions(+), 26 deletions(-)
> create mode 100644 gcc/testsuite/gcc.dg/strub-internal-pr113394.c
>
> diff --git a/gcc/ipa-strub.cc b/gcc/ipa-strub.cc
> index e1b07016b8879..0ee063c9eddc4 100644
> --- a/gcc/ipa-strub.cc
> +++ b/gcc/ipa-strub.cc
> @@ -2052,36 +2052,17 @@ walk_regimplify_phi (gphi *stmt)
> return needs_commit;
> }
>
> -/* Create a reference type to use for PARM when turning it into a reference.
> - NONALIASED causes the reference type to gain its own separate alias set,
> so
> - that accessing the indirectly-passed parm won'will not add aliasing
> - noise. */
> +/* Create a reference type to use for PARM when turning it into a
> + reference. */
>
> static tree
> -build_ref_type_for (tree parm, bool nonaliased = true)
> +build_ref_type_for (tree parm)
> {
> gcc_checking_assert (TREE_CODE (parm) == PARM_DECL);
>
> tree ref_type = build_reference_type (TREE_TYPE (parm));
>
> - if (!nonaliased)
> - return ref_type;
> -
> - /* Each PARM turned indirect still points to the distinct memory area at
> the
> - wrapper, and the reference in unchanging, so we might qualify it, but...
> - const is not really important, since we're only using default defs for
> the
> - reference parm anyway, and not introducing any defs, and restrict seems
> to
> - cause trouble. E.g., libgnat/s-concat3.adb:str_concat_3 has memmoves
> that,
> - if it's wrapped, the memmoves are deleted in dse1. Using a distinct
> alias
> - set seems to not run afoul of this problem, and it hopefully enables the
> - compiler to tell the pointers do point to objects that are not otherwise
> - aliased. */
> - tree qref_type = build_variant_type_copy (ref_type);
> -
> - TYPE_ALIAS_SET (qref_type) = new_alias_set ();
> - record_alias_subset (TYPE_ALIAS_SET (qref_type), get_alias_set (ref_type));
> -
> - return qref_type;
> + return ref_type;
> }
>
> /* Add cgraph edges from current_function_decl to callees in SEQ with
> frequency
> @@ -2909,9 +2890,7 @@ pass_ipa_strub::execute (function *)
> if with transparent reference, and the wrapper doesn't take any
> extra parms that could point into wrapper's parms. So we can
> probably drop the TREE_ADDRESSABLE and keep the TRUE. */
> - tree ref_type = build_ref_type_for (nparm,
> - true
> - || !TREE_ADDRESSABLE (parm));
> + tree ref_type = build_ref_type_for (nparm);
>
> DECL_ARG_TYPE (nparm) = TREE_TYPE (nparm) = ref_type;
> relayout_decl (nparm);
> diff --git a/gcc/testsuite/gcc.dg/strub-internal-pr113394.c
> b/gcc/testsuite/gcc.dg/strub-internal-pr113394.c
> new file mode 100644
> index 0000000000000..d21c209cdf699
> --- /dev/null
> +++ b/gcc/testsuite/gcc.dg/strub-internal-pr113394.c
> @@ -0,0 +1,6 @@
> +/* { dg-do compile } */
> +/* { dg-options "-fstrub=internal -g" } */
> +
> +/* gcc.c-torture/compile/20020210-1.c */
> +/* PR c/5615 */
> +void f(int a, struct {int b[a];} c) {} /* { dg-warning "anonymous struct" }
> */
>
>
> --
> Alexandre Oliva, happy hacker https://FSFLA.org/blogs/lxo/
> Free Software Activist GNU Toolchain Engineer
> More tolerance and less prejudice are key for inclusion and diversity
> Excluding neuro-others for not behaving ""normal"" is *not* inclusive
