Hi,
when debugging PR 63814 I noticed that when cgraph_node::create_clone
was using redirect_edge_duplicating_thunks to redirect two edges to a
thunk of a clone, two thunks were created, one for each edge. The
reason is that even though duplicate_thunk_for_node attempts to locate
an already created thunk, it does so by looking for a caller with
thunk.thunk_p set and the previously created one does not have it set
because (on i686) expand_thunk has expanded the thunk to gimple and
cleared the flag.
This patch fixes the issue by marking such expanded thunks with yet
another flag and then uses the flag to identify such expanded thunks.
Bootstrapped and tested on x86_64-linux and i686-linux. Honza, do you
think this is a good approach? Is the patch OK for trunk?
Thanks,
Martin
2014-11-21 Martin Jambor <mjam...@suse.cz>
* cgraph.h (cgraph_thunk_info): Converted thunk_p to a bit-field.
Added new flag expanded_thunk_p.
* cgraphunit.c (expand_thunk): Set expanded_thunk_p when appropriate.
* cgraphclones.c (duplicate_thunk_for_node): Also re-use an expanded
thunk if available.
Index: src/gcc/cgraph.h
===================================================================
--- src.orig/gcc/cgraph.h
+++ src/gcc/cgraph.h
@@ -552,7 +552,9 @@ struct GTY(()) cgraph_thunk_info {
bool virtual_offset_p;
bool add_pointer_bounds_args;
/* Set to true when alias node is thunk. */
- bool thunk_p;
+ unsigned thunk_p : 1;
+ /* Set when this is an already expanded thunk. */
+ unsigned expanded_thunk_p : 1;
};
/* Information about the function collected locally.
Index: src/gcc/cgraphclones.c
===================================================================
--- src.orig/gcc/cgraphclones.c
+++ src/gcc/cgraphclones.c
@@ -311,7 +311,7 @@ duplicate_thunk_for_node (cgraph_node *t
cgraph_edge *cs;
for (cs = node->callers; cs; cs = cs->next_caller)
- if (cs->caller->thunk.thunk_p
+ if ((cs->caller->thunk.thunk_p || cs->caller->thunk.expanded_thunk_p)
&& cs->caller->thunk.this_adjusting == thunk->thunk.this_adjusting
&& cs->caller->thunk.fixed_offset == thunk->thunk.fixed_offset
&& cs->caller->thunk.virtual_offset_p == thunk->thunk.virtual_offset_p
Index: src/gcc/cgraphunit.c
===================================================================
--- src.orig/gcc/cgraphunit.c
+++ src/gcc/cgraphunit.c
@@ -1504,6 +1504,7 @@ cgraph_node::expand_thunk (bool output_a
set_cfun (NULL);
TREE_ASM_WRITTEN (thunk_fndecl) = 1;
thunk.thunk_p = false;
+ thunk.expanded_thunk_p = true;
analyzed = false;
}
else
@@ -1686,6 +1687,7 @@ cgraph_node::expand_thunk (bool output_a
/* Since we want to emit the thunk, we explicitly mark its name as
referenced. */
thunk.thunk_p = false;
+ thunk.expanded_thunk_p = true;
lowered = true;
bitmap_obstack_release (NULL);
}
