Add out-of-line versions of some <stdatomic.h> functions (PR c/65083).

PR c/65083 notes that some functions in <stdatomic.h> are normal
functions, not generic functions, and so need to have out-of-line
copies that can be called when macro expansion is suppressed (unlike
the generic functions where DR#419 makes it undefined if you suppress
a macro expansion).

This patch adds such out-of-line definitions in libatomic for those
six functions, at a new LIBATOMIC_1.2 symbol version, as trivial
wrappers to the <stdatomic.h> macros, along with declarations of those
functions in <stdatomic.h>.  Tests are added that are based on the
corresponding tests for the macros, but with parentheses around the
function names to force the out-of-line functions to be used.

Bootstrapped with no regressions on x86_64-pc-linux-gnu.

gcc:
	* ginclude/stdatomic.h (atomic_thread_fence, atomic_signal_fence)
	(atomic_flag_test_and_set, atomic_flag_test_and_set_explicit)
	(atomic_flag_clear, atomic_flag_clear_explicit): Declare as
	functions before defining as macros.

gcc/testsuite:
	* gcc.dg/atomic/stdatomic-fence-2.c,
	gcc.dg/atomic/stdatomic-flag-2.c: New tests.

libatomic:
	* fence.c, flag.c: New files.
	* Makefile.am (libatomic_la_SOURCES): Add fence.c and flag.c.
	* Makefile.in: Regenerate.
	* configure.ac (libtool_VERSION): Change to 3:0:2.
	* configure: Regenerate.
	* libatomic.map (LIBATOMIC_1.2): New symbol version.

From-SVN: r230578

1 files changed, 64 insertions, 0 deletions

diff --git a/libatomic/flag.c b/libatomic/flag.c
new file mode 100644
index 00000000000..bc8cc14a6c3
--- /dev/null
+++ b/libatomic/flag.c
@@ -0,0 +1,64 @@
+/* Copyright (C) 2015 Free Software Foundation, Inc.
+
+   This file is part of the GNU Atomic Library (libatomic).
+
+   Libatomic is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   Libatomic is distributed in the hope that it will be useful, but WITHOUT ANY
+   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+   FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+   more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "libatomic_i.h"
+
+#include <stdatomic.h>
+
+/* Out-of-line versions of <stdatomic.h> flag functions.  */
+
+/* Atomically set *OBJECT to true, returning the previous value.  */
+
+_Bool
+(atomic_flag_test_and_set) (volatile atomic_flag *object)
+{
+  return atomic_flag_test_and_set (object);
+}
+
+/* Atomically set *OBJECT to true, returning the previous value, with
+   memory affected according to ORDER.  */
+
+_Bool
+(atomic_flag_test_and_set_explicit) (volatile atomic_flag *object,
+				     memory_order order)
+{
+  return atomic_flag_test_and_set_explicit (object, order);
+}
+
+/* Atomically set *OBJECT to false.  */
+
+void
+(atomic_flag_clear) (volatile atomic_flag *object)
+{
+  atomic_flag_clear (object);
+}
+
+/* Atomically set *OBJECT to false, with memory affected according to
+   ORDER.  */
+
+void
+(atomic_flag_clear_explicit) (volatile atomic_flag *object,
+			      memory_order order)
+{
+  return atomic_flag_clear_explicit (object, order);
+}