Hi,
this patch fix wrong code with Firefox and LTO which Martin Liska tracked down.
The problem is that unlike DECL_ABSTRACT_ORIGIN that always point to transitive
closure of origin, BLOCK_ABSTRACT_ORIGIN can iterate. In firefox we see a
function split by ipa-split which contains a construction we inlined from.
Consequently, the BLOCK_ABSTRACT_ORIGIN is an another block whose
BLOCK_ABSTRACT_ORIGIN is the ctor instead of BLOCK_ABSTRACT_ORIGIN beaing ctor
idrectly as exxpected by inlined_polymorphic_ctor_dtor_block_p.
Bootstrapped/regtested x86_64-linux, will commit it tonight if there are no
complains. Note that the function block_origin is different from
ultimate_block_origin used by dwarf2out because it walks abstract blocks that
is needed, because the blocks we seek for are abstract.
I think the release branches are also affected.
Honza
* ipa-polymorphic-call.c (block_origin): New function.
(inlined_polymorphic_ctor_dtor_block_p,
noncall_stmt_may_be_vtbl_ptr_store): Use it.
Index: ipa-polymorphic-call.c
===================================================================
--- ipa-polymorphic-call.c (revision 232293)
+++ ipa-polymorphic-call.c (working copy)
@@ -477,6 +477,20 @@ contains_type_p (tree outer_type, HOST_W
consider_bases);
}
+/* Unlike ABSTRACT_ORIGIN, the BLOCK_ABSTRACT_ORIGIN can iterate. Look up
+ the real origin of BLOCK. */
+
+static tree
+block_origin (tree block)
+{
+ if (!BLOCK_ABSTRACT_ORIGIN (block))
+ return NULL;
+ while (TREE_CODE (block) == BLOCK && BLOCK_ABSTRACT_ORIGIN (block)
+ && BLOCK_ABSTRACT_ORIGIN (block) != block)
+ block = BLOCK_ABSTRACT_ORIGIN (block);
+ return DECL_P (block) ? DECL_ORIGIN (block) : block;
+}
+
/* Return a FUNCTION_DECL if BLOCK represents a constructor or destructor.
If CHECK_CLONES is true, also check for clones of ctor/dtors. */
@@ -484,7 +498,7 @@ contains_type_p (tree outer_type, HOST_W
tree
inlined_polymorphic_ctor_dtor_block_p (tree block, bool check_clones)
{
- tree fn = BLOCK_ABSTRACT_ORIGIN (block);
+ tree fn = block_origin (block);
if (fn == NULL || TREE_CODE (fn) != FUNCTION_DECL)
return NULL_TREE;
@@ -1143,7 +1157,7 @@ noncall_stmt_may_be_vtbl_ptr_store (gimp
for (tree block = gimple_block (stmt); block && TREE_CODE (block) == BLOCK;
block = BLOCK_SUPERCONTEXT (block))
if (BLOCK_ABSTRACT_ORIGIN (block)
- && TREE_CODE (BLOCK_ABSTRACT_ORIGIN (block)) == FUNCTION_DECL)
+ && TREE_CODE (block_origin (block)) == FUNCTION_DECL)
return inlined_polymorphic_ctor_dtor_block_p (block, false);
return (TREE_CODE (TREE_TYPE (current_function_decl)) == METHOD_TYPE
&& (DECL_CXX_CONSTRUCTOR_P (current_function_decl)
