[PATCH] free_lang_data fixes (PR lto/89692)
Richard Biener
rguenther@suse.de
Thu Mar 21 11:16:00 GMT 2019
On Thu, 21 Mar 2019, Jakub Jelinek wrote:
> On Thu, Mar 21, 2019 at 11:25:38AM +0100, Richard Biener wrote:
> > On Thu, 21 Mar 2019, Jakub Jelinek wrote:
> >
> > > On Thu, Mar 21, 2019 at 11:13:41AM +0100, Richard Biener wrote:
> > > > > Would you prefer to have say add_tree_to_fld_list that does what it does now
> > > > > and has just 2 callers in find_decls_types_r and a new
> > > > > maybe_add_tree_to_fld_list that would do
> > > > > if (!fld->pset.add (t))
> > > > > add_tree_to_fld_list (t, fld);
> > > > > and change all the other add_tree_to_fld_list callers?
> > > >
> > > > Not sure if that's needed, if you leave find_decls_types_r alone then
> > > > always doing the check should work, no?
> > >
> > > Well, find_decls_types_r uses add_tree_to_fld_list, so the if (fld->pset.add
> > > (t)) return; can't be in that function. If we want to simplify all the
> > > other callers, so that they don't need to do it manually, then the only
> > > options I see is call some other function in those spots that does this
> > > additional check, or call another function that doesn't do that in the
> > > two spots of find_decls_types_r, or add another argument to the function
> > > say with default argument and test that argument before the fld->pset.add.
> > > E.g. , bool do_add = true and if (do_add && fld->pset.add (t)) return;
> > > and adjust the two calls in find_decls_types_r to call
> > > add_tree_to_fld_list (t, fld, false);
> > > Or keep the patch as is, do the tests before each but the two
> > > add_tree_to_fld_list calls.
> >
> > I'd have kept the patch but made the add_tree_to_fld_list following
> > the new fld->pset.add (t) calls conditional on the result.
>
> Ok, so incremental diff:
> --- gcc/tree.c 2019-03-20 20:16:12.277091827 +0100
> +++ gcc/tree.c 2019-03-21 11:33:17.008936452 +0100
> @@ -5215,8 +5215,8 @@
> if (inner_type)
> TREE_TYPE (v) = inner_type;
> gcc_checking_assert (fld_type_variant_equal_p (t,v, inner_type));
> - fld->pset.add (v);
> - add_tree_to_fld_list (v, fld);
> + if (!fld->pset.add (v))
> + add_tree_to_fld_list (v, fld);
> return v;
> }
>
> @@ -5324,8 +5324,8 @@
> copy = build_distinct_type_copy (t);
>
> /* It is possible that type was not seen by free_lang_data yet. */
> - fld->pset.add (copy);
> - add_tree_to_fld_list (copy, fld);
> + if (!fld->pset.add (copy))
> + add_tree_to_fld_list (copy, fld);
> TYPE_SIZE (copy) = NULL;
> TYPE_USER_ALIGN (copy) = 0;
> TYPE_SIZE_UNIT (copy) = NULL;
> @@ -5480,8 +5480,8 @@
> & ~TYPE_QUAL_CONST
> & ~TYPE_QUAL_VOLATILE;
> TREE_VALUE (p) = build_qualified_type (arg_type, quals);
> - fld->pset.add (TREE_VALUE (p));
> - free_lang_data_in_type (TREE_VALUE (p), fld);
> + if (!fld->pset.add (TREE_VALUE (p)))
> + free_lang_data_in_type (TREE_VALUE (p), fld);
> }
> /* C++ FE uses TREE_PURPOSE to store initial values. */
> TREE_PURPOSE (p) = NULL;
>
> and full patch below? Ok for trunk if it passes bootstrap/regtest?
OK.
Thanks,
Richard.
> 2019-03-21 Jan Hubicka <hubicka@ucw.cz>
> Jakub Jelinek <jakub@redhat.com>
>
> PR lto/89692
> * tree.c (fld_type_variant, fld_incomplete_type_of,
> fld_process_array_type): Call fld->pset.add and don't call
> add_tree_to_fld_list if it returns true.
> (free_lang_data_in_type): Likewise. Purge non-marked types from
> TYPE_NEXT_VARIANT list.
> (find_decls_types_r): Call fld_worklist_push for TYPE_CANONICAL (t).
>
> * g++.dg/other/pr89692.C: New test.
>
> --- gcc/tree.c.jj 2019-03-20 12:24:56.443322228 +0100
> +++ gcc/tree.c 2019-03-21 11:33:17.008936452 +0100
> @@ -5215,7 +5215,8 @@ fld_type_variant (tree first, tree t, st
> if (inner_type)
> TREE_TYPE (v) = inner_type;
> gcc_checking_assert (fld_type_variant_equal_p (t,v, inner_type));
> - add_tree_to_fld_list (v, fld);
> + if (!fld->pset.add (v))
> + add_tree_to_fld_list (v, fld);
> return v;
> }
>
> @@ -5253,7 +5254,8 @@ fld_process_array_type (tree t, tree t2,
> array = build_array_type_1 (t2, TYPE_DOMAIN (t),
> TYPE_TYPELESS_STORAGE (t), false);
> TYPE_CANONICAL (array) = TYPE_CANONICAL (t);
> - add_tree_to_fld_list (array, fld);
> + if (!fld->pset.add (array))
> + add_tree_to_fld_list (array, fld);
> }
> return array;
> }
> @@ -5298,7 +5300,8 @@ fld_incomplete_type_of (tree t, struct f
> TYPE_REF_CAN_ALIAS_ALL (t));
> gcc_assert (TYPE_CANONICAL (t2) != t2
> && TYPE_CANONICAL (t2) == TYPE_CANONICAL (TREE_TYPE (t)));
> - add_tree_to_fld_list (first, fld);
> + if (!fld->pset.add (first))
> + add_tree_to_fld_list (first, fld);
> return fld_type_variant (first, t, fld);
> }
> return t;
> @@ -5321,7 +5324,8 @@ fld_incomplete_type_of (tree t, struct f
> copy = build_distinct_type_copy (t);
>
> /* It is possible that type was not seen by free_lang_data yet. */
> - add_tree_to_fld_list (copy, fld);
> + if (!fld->pset.add (copy))
> + add_tree_to_fld_list (copy, fld);
> TYPE_SIZE (copy) = NULL;
> TYPE_USER_ALIGN (copy) = 0;
> TYPE_SIZE_UNIT (copy) = NULL;
> @@ -5445,6 +5449,18 @@ free_lang_data_in_type (tree type, struc
>
> TYPE_NEEDS_CONSTRUCTING (type) = 0;
>
> + /* Purge non-marked variants from the variants chain, so that they
> + don't reappear in the IL after free_lang_data. */
> + while (TYPE_NEXT_VARIANT (type)
> + && !fld->pset.contains (TYPE_NEXT_VARIANT (type)))
> + {
> + tree t = TYPE_NEXT_VARIANT (type);
> + TYPE_NEXT_VARIANT (type) = TYPE_NEXT_VARIANT (t);
> + /* Turn the removed types into distinct types. */
> + TYPE_MAIN_VARIANT (t) = t;
> + TYPE_NEXT_VARIANT (t) = NULL_TREE;
> + }
> +
> if (TREE_CODE (type) == FUNCTION_TYPE)
> {
> TREE_TYPE (type) = fld_simplified_type (TREE_TYPE (type), fld);
> @@ -5464,7 +5480,8 @@ free_lang_data_in_type (tree type, struc
> & ~TYPE_QUAL_CONST
> & ~TYPE_QUAL_VOLATILE;
> TREE_VALUE (p) = build_qualified_type (arg_type, quals);
> - free_lang_data_in_type (TREE_VALUE (p), fld);
> + if (!fld->pset.add (TREE_VALUE (p)))
> + free_lang_data_in_type (TREE_VALUE (p), fld);
> }
> /* C++ FE uses TREE_PURPOSE to store initial values. */
> TREE_PURPOSE (p) = NULL;
> @@ -5886,8 +5903,7 @@ find_decls_types_r (tree *tp, int *ws, v
> ctx = BLOCK_SUPERCONTEXT (ctx);
> fld_worklist_push (ctx, fld);
> }
> - /* Do not walk TYPE_CANONICAL. We do not stream it and thus do not
> - and want not to reach unused types this way. */
> + fld_worklist_push (TYPE_CANONICAL (t), fld);
>
> if (RECORD_OR_UNION_TYPE_P (t) && TYPE_BINFO (t))
> {
> --- gcc/testsuite/g++.dg/other/pr89692.C.jj 2019-03-20 20:20:10.233278697 +0100
> +++ gcc/testsuite/g++.dg/other/pr89692.C 2019-03-20 20:19:53.193551778 +0100
> @@ -0,0 +1,20 @@
> +// PR lto/89692
> +// { dg-do compile }
> +// { dg-require-effective-target lto }
> +// { dg-options "-flto -O2" }
> +
> +struct S {
> + short int a, b;
> + unsigned char c : 1;
> +};
> +
> +bool
> +foo (void)
> +{
> + unsigned char d[sizeof (S)] = { 0 };
> + S e;
> +
> + __builtin_memcpy (&e, d, sizeof (d));
> +
> + return e.c == d[0];
> +}
>
>
> Jakub
>
--
Richard Biener <rguenther@suse.de>
SUSE Linux GmbH, Maxfeldstrasse 5, 90409 Nuernberg, Germany;
GF: Felix Imendörffer, Mary Higgins, Sri Rasiah; HRB 21284 (AG NÌrnberg)
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