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[PATCH] Don't hash pointers for IPA ICF, instead hash ->order ints (PR ipa/65521)
- From: Jakub Jelinek <jakub at redhat dot com>
- To: Richard Biener <rguenther at suse dot de>, Jan Hubicka <hubicka at ucw dot cz>, Martin LiÅka <mliska at suse dot cz>
- Cc: gcc-patches at gcc dot gnu dot org
- Date: Mon, 23 Mar 2015 16:03:13 +0100
- Subject: [PATCH] Don't hash pointers for IPA ICF, instead hash ->order ints (PR ipa/65521)
- Authentication-results: sourceware.org; auth=none
- Reply-to: Jakub Jelinek <jakub at redhat dot com>
Hi!
The recent IPA ICF hashing changes broke -fcompare-debug, hashing in
pointers is not stable not just for -fcompare-debug, but supposedly even
just different runs with the exact same options could yield different
assembly. Hashing on DECL_UID is not good either, that is not guaranteed to
be the same for -g/-g0.
symtab_node::order is printed in the -fdump-final-insns= dumps, so I assume
it must be stable across -g/-g0.
Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
2014-03-23 Jakub Jelinek <jakub@redhat.com>
PR ipa/65521
* ipa-icf.c (sem_item::update_hash_by_addr_refs): Hash
ultimate_alias_target ()->order ints instead of
ultimate_alias_target () pointers.
* gcc.dg/pr65521.c: New test.
--- gcc/ipa-icf.c.jj 2015-03-23 08:47:53.000000000 +0100
+++ gcc/ipa-icf.c 2015-03-23 11:02:53.129630089 +0100
@@ -575,7 +575,7 @@ sem_item::update_hash_by_addr_refs (hash
{
ref = node->iterate_reference (i, ref);
if (ref->address_matters_p () || !m_symtab_node_map.get (ref->referred))
- hstate.add_ptr (ref->referred->ultimate_alias_target ());
+ hstate.add_int (ref->referred->ultimate_alias_target ()->order);
}
if (is_a <cgraph_node *> (node))
@@ -585,7 +585,7 @@ sem_item::update_hash_by_addr_refs (hash
{
sem_item **result = m_symtab_node_map.get (e->callee);
if (!result)
- hstate.add_ptr (e->callee->ultimate_alias_target ());
+ hstate.add_int (e->callee->ultimate_alias_target ()->order);
}
}
--- gcc/testsuite/gcc.dg/pr65521.c.jj 2015-03-23 11:03:16.190252436 +0100
+++ gcc/testsuite/gcc.dg/pr65521.c 2015-03-23 11:02:07.000000000 +0100
@@ -0,0 +1,39 @@
+/* PR ipa/65521 */
+/* { dg-do compile } */
+/* { dg-options "-O2 -fcompare-debug" } */
+
+struct S { int s; };
+int f6 (void *, unsigned long);
+int f7 (int, int *, unsigned long);
+int f8 (void);
+int f9 (void (*) (void));
+
+int
+f1 (void *p)
+{
+ return f6 (p, 256UL);
+}
+
+int
+f2 (void *p)
+{
+ return f6 (p, 256UL);
+}
+
+int
+f3 (struct S *x)
+{
+ return f7 (f8 (), &x->s, 16UL);
+}
+
+int
+f4 (struct S *x)
+{
+ return f7 (f8 (), &x->s, 16UL);
+}
+
+void
+f5 (void)
+{
+ f9 (f5);
+}
Jakub