On 8/26/2021 9:27 AM, H.J. Lu via Gcc-patches wrote:
On Thu, Aug 26, 2021 at 2:49 AM Jan Hubicka <hubi...@ucw.cz> wrote:
On 8/26/21 10:33, Christophe Lyon via Gcc-patches wrote:
Can you have a look?
Please create a PR for it.
I have fix, so perhaps there is no need for PR :)
I am testing the following - the problem was that try_merge_with missed
some merges because how unoredered_remove handles the vector.
Bootstrapping/regtesteing x86_64-linux.
Honza
diff --git a/gcc/ipa-modref-tree.h b/gcc/ipa-modref-tree.h
index 6f6932f0875..b27c9689987 100644
--- a/gcc/ipa-modref-tree.h
+++ b/gcc/ipa-modref-tree.h
@@ -322,6 +322,20 @@ struct GTY((user)) modref_ref_node
every_access = true;
}
+ /* Verify that list does not contain redundant accesses. */
+ void verify ()
+ {
+ size_t i, i2;
+ modref_access_node *a, *a2;
+
+ FOR_EACH_VEC_SAFE_ELT (accesses, i, a)
+ {
+ FOR_EACH_VEC_SAFE_ELT (accesses, i2, a2)
+ if (i != i2)
+ gcc_assert (!a->contains (*a2));
+ }
+ }
+
/* Insert access with OFFSET and SIZE.
Collapse tree if it has more than MAX_ACCESSES entries.
If RECORD_ADJUSTMENTs is true avoid too many interval extensions.
@@ -337,6 +351,9 @@ struct GTY((user)) modref_ref_node
size_t i;
modref_access_node *a2;
+ if (flag_checking)
+ verify ();
+
if (!a.useful_p ())
{
if (!every_access)
@@ -392,13 +409,15 @@ private:
size_t i;
FOR_EACH_VEC_SAFE_ELT (accesses, i, a2)
- if (i != index)
- if ((*accesses)[index].contains (*a2)
- || (*accesses)[index].merge (*a2, false))
+ if (i != index
+ && ((*accesses)[index].contains (*a2)
+ || (*accesses)[index].merge (*a2, false)))
{
- if (index == accesses->length () - 1)
- index = i;
accesses->unordered_remove (i);
+ if (index == accesses->length ())
+ index = i;
+ else
+ i--;
}
}
};
I think
commit f075b8c5adcf9cb6336563c472c8d624c54184db
Author: Jan Hubicka <hubi...@ucw.cz>
Date: Thu Aug 26 15:33:56 2021 +0200
Fix off-by-one error in try_merge_with
gcc/ChangeLog:
* ipa-modref-tree.h (modref_ref_node::verify): New member
functoin.
(modref_ref_node::insert): Use it.
(modref_ref_node::try_mere_with): Fix off by one error.
caused libgo build failure on Linux/i686:
It's also causing kernel build failures on a variety of targets. I just
sent a testcase to Jan directly.
jeff
