Hi,
I have noticed that we often run IPA-transformation phases multiple
times. The reason is that when a virtual clone is created, it starts
with an empty ipa_transforms_to_apply vector and all subsequent IPA
passes that see it are pushed onto it. The original node gets these
pushed on their ipa_transforms_to_apply too. Later on, when a clone
receives its body, in tree_function_versioning, the contents of
original node's ipa_transforms_to_apply is added to clone's
ipa_transforms_to_apply (in a slightly convoluted way). I do not
understand how this was supposed to work but obviously we can and do
end up with multiple copies of a few passes in ipa_transforms_to_apply
of the clone.
I believe the correct thing to do is to copy the vector when the
virtual clone is created and remove the part in
tree_function_versioning that does the copying. I have verified that
we no longer call transformation of IPA-CP multiple times when we
previously did and added asserts to check that no other caller of
tree_function_versioning expects to have the vector copied.
Bootstrapped and tested on x86_64-linux, OK for trunk?
Thanks,
Martin
2014-04-10 Martin Jambor <mjam...@suse.cz>
* cgraphclones.c (cgraph_create_virtual_clone): Duplicate
ipa_transforms_to_apply.
(cgraph_function_versioning): Assert that old_node has empty
ipa_transforms_to_apply.
* trans-mem.c (ipa_tm_create_version): Likewise.
* tree-inline.c (tree_function_versioning): Do not duplicate
ipa_transforms_to_apply.
Index: src/gcc/cgraphclones.c
===================================================================
--- src.orig/gcc/cgraphclones.c
+++ src/gcc/cgraphclones.c
@@ -600,6 +600,9 @@ cgraph_create_virtual_clone (struct cgra
}
else
new_node->clone.combined_args_to_skip = args_to_skip;
+ if (old_node->ipa_transforms_to_apply.exists ())
+ new_node->ipa_transforms_to_apply
+ = old_node->ipa_transforms_to_apply.copy ();
cgraph_call_node_duplication_hooks (old_node, new_node);
@@ -971,6 +974,7 @@ cgraph_function_versioning (struct cgrap
cgraph_copy_node_for_versioning (old_version_node, new_decl,
redirect_callers, bbs_to_copy);
+ gcc_assert (!old_version_node->ipa_transforms_to_apply.exists ());
/* Copy the OLD_VERSION_NODE function tree to the new version. */
tree_function_versioning (old_decl, new_decl, tree_map, false, args_to_skip,
skip_return, bbs_to_copy, new_entry_block);
Index: src/gcc/trans-mem.c
===================================================================
--- src.orig/gcc/trans-mem.c
+++ src/gcc/trans-mem.c
@@ -4914,6 +4914,7 @@ ipa_tm_create_version (struct cgraph_nod
if (DECL_ONE_ONLY (new_decl))
DECL_COMDAT_GROUP (new_decl) = tm_mangle (DECL_COMDAT_GROUP (old_decl));
+ gcc_assert (!old_node->ipa_transforms_to_apply.exists ());
new_node = cgraph_copy_node_for_versioning (old_node, new_decl, vNULL, NULL);
new_node->local.local = false;
new_node->externally_visible = old_node->externally_visible;
Index: src/gcc/tree-inline.c
===================================================================
--- src.orig/gcc/tree-inline.c
+++ src/gcc/tree-inline.c
@@ -5323,18 +5323,6 @@ tree_function_versioning (tree old_decl,
id.dst_node = new_version_node;
id.src_cfun = DECL_STRUCT_FUNCTION (old_decl);
id.blocks_to_copy = blocks_to_copy;
- if (id.src_node->ipa_transforms_to_apply.exists ())
- {
- vec<ipa_opt_pass> old_transforms_to_apply
- = id.dst_node->ipa_transforms_to_apply;
- unsigned int i;
-
- id.dst_node->ipa_transforms_to_apply
- = id.src_node->ipa_transforms_to_apply.copy ();
- for (i = 0; i < old_transforms_to_apply.length (); i++)
- id.dst_node->ipa_transforms_to_apply.safe_push
(old_transforms_to_apply[i]);
- old_transforms_to_apply.release ();
- }
id.copy_decl = copy_decl_no_change;
id.transform_call_graph_edges
