atomic_base.h (atomic_thread_fence): Call builtin.

2011-11-07  Andrew MacLeod  <amacleod@redhat.com>

	libstdc++-v3
	* include/bits/atomic_base.h (atomic_thread_fence): Call builtin.
	(atomic_signal_fence): Call builtin.
	(atomic_flag::test_and_set): Call __atomic_exchange when it is lockfree,
	otherwise fall back to call __sync_lock_test_and_set.
	(atomic_flag::clear): Call __atomic_store when it is lockfree,
	otherwise fall back to call __sync_lock_release.

	gcc
	* doc/extend.texi: Docuemnt behaviour change for __atomic_exchange and
	__atomic_store.
	* optabs.c (expand_atomic_exchange): Expand to __sync_lock_test_and_set
	only when originated from that builtin.
	(expand_atomic_store): Expand to __sync_lock_release when originated
	from that builtin.
	* builtins.c (expand_builtin_sync_lock_test_and_set): Add flag that
	expand_atomic_exchange call originated from here.
	(expand_builtin_sync_lock_release): Add flag that expand_atomic_store
	call originated from here.
	(expand_builtin_atomic_exchange): Add origination flag.
	(expand_builtin_atomic_store): Add origination flag.
	* expr.h (expand_atomic_exchange, expand_atomic_store): Add boolean 
	parameters to indicate implementation fall back options.

From-SVN: r181111

1 files changed, 2 insertions, 2 deletions

diff --git a/gcc/expr.h b/gcc/expr.h
index 1623ad9..2cc8152 100644
--- a/gcc/expr.h
+++ b/gcc/expr.h
@@ -215,9 +215,9 @@ rtx emit_conditional_add (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
 rtx expand_sync_operation (rtx, rtx, enum rtx_code);
 rtx expand_sync_fetch_operation (rtx, rtx, enum rtx_code, bool, rtx);
 
-rtx expand_atomic_exchange (rtx, rtx, rtx, enum memmodel);
+rtx expand_atomic_exchange (rtx, rtx, rtx, enum memmodel, bool);
 rtx expand_atomic_load (rtx, rtx, enum memmodel);
-rtx expand_atomic_store (rtx, rtx, enum memmodel);
+rtx expand_atomic_store (rtx, rtx, enum memmodel, bool);
 rtx expand_atomic_fetch_op (rtx, rtx, rtx, enum rtx_code, enum memmodel, 
 			      bool);
 void expand_atomic_thread_fence (enum memmodel);