Hi,
this is the patch implementing renaming and fixing logic in ipa-icf/lto-symtab
WRT compuattion of this flag. I don't seem to be able to construct testcase for
this: the merged flag is currently used in inliner only to decide whether to
ingore optimize_size/optimize levels which should not lead to wrong code and
I can't grep LTO dumps from testsuite.
Bootstrapped/regtested x86_64-linux, comitted
Honza
* ipa-inline.c (can_inline_edge_p) Use merged_comdat.
* cgraphclones.c (cgraph_node::create_clone): Use merged_comdat.
* cgraph.c (cgraph_node::dump): Dump merged_comdat.
* ipa-icf.c (sem_function::merge): Drop merged_comdat when merging
comdat and non-comdat.
* cgraph.h (cgraph_node): Rename merged to merged_comdat.
* ipa-inline-analysis.c (simple_edge_hints): Check both merged_comdat
and icf_merged.
* lto-symtab.c (lto_cgraph_replace_node): Update code computing
merged_comdat.
Index: cgraphclones.c
===================================================================
--- cgraphclones.c (revision 231239)
+++ cgraphclones.c (working copy)
@@ -433,7 +433,7 @@ cgraph_node::create_clone (tree new_decl
new_node->tp_first_run = tp_first_run;
new_node->tm_clone = tm_clone;
new_node->icf_merged = icf_merged;
- new_node->merged = merged;
+ new_node->merged_comdat = merged_comdat;
new_node->clone.tree_map = NULL;
new_node->clone.args_to_skip = args_to_skip;
Index: ipa-icf.c
===================================================================
--- ipa-icf.c (revision 231239)
+++ ipa-icf.c (working copy)
@@ -1352,10 +1352,15 @@ sem_function::merge (sem_item *alias_ite
gcc_assert (alias->icf_merged || remove || redirect_callers);
original->icf_merged = true;
- /* Inform the inliner about cross-module merging. */
- if ((original->lto_file_data || alias->lto_file_data)
- && original->lto_file_data != alias->lto_file_data)
- local_original->merged = original->merged = true;
+ /* We use merged flag to track cases where COMDAT function is known to be
+ compatible its callers. If we merged in non-COMDAT, we need to give up
+ on this optimization. */
+ if (original->merged_comdat && !alias->merged_comdat)
+ {
+ if (dump_file)
+ fprintf (dump_file, "Dropping merged_comdat flag.\n\n");
+ local_original->merged_comdat = original->merged_comdat = false;
+ }
if (remove)
{
Index: ipa-inline.c
===================================================================
--- ipa-inline.c (revision 231239)
+++ ipa-inline.c (working copy)
@@ -466,7 +466,7 @@ can_inline_edge_p (struct cgraph_edge *e
optimized with the optimization flags of module they are used in.
Also do not care about mixing up size/speed optimization when
DECL_DISREGARD_INLINE_LIMITS is set. */
- else if ((callee->merged
+ else if ((callee->merged_comdat
&& !lookup_attribute ("optimize",
DECL_ATTRIBUTES (caller->decl)))
|| DECL_DISREGARD_INLINE_LIMITS (callee->decl))
Index: ipa-inline-analysis.c
===================================================================
--- ipa-inline-analysis.c (revision 231239)
+++ ipa-inline-analysis.c (working copy)
@@ -3708,7 +3708,7 @@ simple_edge_hints (struct cgraph_edge *e
if (callee->lto_file_data && edge->caller->lto_file_data
&& edge->caller->lto_file_data != callee->lto_file_data
- && !callee->merged)
+ && !callee->merged_comdat && !callee->icf_merged)
hints |= INLINE_HINT_cross_module;
return hints;
Index: cgraph.c
===================================================================
--- cgraph.c (revision 231239)
+++ cgraph.c (working copy)
@@ -1994,6 +1994,8 @@ cgraph_node::dump (FILE *f)
fprintf (f, " tm_clone");
if (icf_merged)
fprintf (f, " icf_merged");
+ if (merged_comdat)
+ fprintf (f, " merged_comdat");
if (nonfreeing_fn)
fprintf (f, " nonfreeing_fn");
if (DECL_STATIC_CONSTRUCTOR (decl))
Index: cgraph.h
===================================================================
--- cgraph.h (revision 231239)
+++ cgraph.h (working copy)
@@ -1333,7 +1333,7 @@ public:
accesses trapping. */
unsigned nonfreeing_fn : 1;
/* True if there was multiple COMDAT bodies merged by lto-symtab. */
- unsigned merged : 1;
+ unsigned merged_comdat : 1;
/* True if function was created to be executed in parallel. */
unsigned parallelized_function : 1;
/* True if function is part split out by ipa-split. */
Index: lto/lto-symtab.c
===================================================================
--- lto/lto-symtab.c (revision 231239)
+++ lto/lto-symtab.c (working copy)
@@ -63,8 +63,9 @@ lto_cgraph_replace_node (struct cgraph_n
gcc_assert (!prevailing_node->global.inlined_to);
prevailing_node->mark_address_taken ();
}
- if (node->definition && prevailing_node->definition)
- prevailing_node->merged = true;
+ if (node->definition && prevailing_node->definition
+ && DECL_COMDAT (node->decl) && DECL_COMDAT (prevailing_node->decl))
+ prevailing_node->merged_comdat = true;
/* Redirect all incoming edges. */
compatible_p
