[src/trunk]: src/common/lib/libc Provide a basic implementation of __atomic_l...

[joerg <joerg%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/af0f01d12f52
branches:  trunk
changeset: 330341:af0f01d12f52
user:      joerg <joerg%NetBSD.org@localhost>
date:      Sat Jul 05 20:44:46 2014 +0000

description:
Provide a basic implementation of __atomic_load_* and __atomic_store_*,
used by GCC and LLVM as backing for C11/C++11 atomics, if the hardware
is not known to have corresponding features. Include it on ARM as LLVM
and libc++ hit it when compiled for ARMv4.

diffstat:

 common/lib/libc/arch/arm/atomic/Makefile.inc |   5 +-
 common/lib/libc/atomic/atomic_load.c         |  54 ++++++++++++++++++++++++++++
 common/lib/libc/atomic/atomic_store.c        |  52 ++++++++++++++++++++++++++
 3 files changed, 109 insertions(+), 2 deletions(-)

diffs (133 lines):

diff -r 23e26b66b933 -r af0f01d12f52 common/lib/libc/arch/arm/atomic/Makefile.inc
--- a/common/lib/libc/arch/arm/atomic/Makefile.inc      Sat Jul 05 20:17:50 2014 +0000
+++ b/common/lib/libc/arch/arm/atomic/Makefile.inc      Sat Jul 05 20:44:46 2014 +0000
@@ -1,4 +1,4 @@
-#      $NetBSD: Makefile.inc,v 1.22 2014/03/04 16:15:28 matt Exp $
+#      $NetBSD: Makefile.inc,v 1.23 2014/07/05 20:44:46 joerg Exp $
 
 .ifnmake obj
 .include "${NETBSDSRCDIR}/common/lib/libc/arch/arm/features.mk"
@@ -23,7 +23,8 @@
                atomic_and_16_cas.c atomic_and_8_cas.c \
                atomic_add_16_cas.c atomic_add_8_cas.c \
                atomic_swap_16_cas.c atomic_swap_8_cas.c \
-               atomic_cas_32_cas.c atomic_cas_16_cas.c atomic_cas_8_cas.c
+               atomic_cas_32_cas.c atomic_cas_16_cas.c atomic_cas_8_cas.c \
+               atomic_load.c atomic_store.c
 .endif
 
 .else
diff -r 23e26b66b933 -r af0f01d12f52 common/lib/libc/atomic/atomic_load.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/common/lib/libc/atomic/atomic_load.c      Sat Jul 05 20:44:46 2014 +0000
@@ -0,0 +1,54 @@
+/*     $NetBSD: atomic_load.c,v 1.1 2014/07/05 20:44:46 joerg Exp $    */
+
+/*-
+ * Copyright (c) 2014 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: atomic_load.c,v 1.1 2014/07/05 20:44:46 joerg Exp $");
+
+#include "atomic_op_namespace.h"
+
+#include <sys/types.h>
+#include <sys/atomic.h>
+
+#define atomic_load_n(n,b) \
+uint ## b ## _t __atomic_load_ ## n(volatile uint ## b ## _t *); \
+uint ## b ## _t \
+__atomic_load_ ## n(volatile uint ## b ## _t *ptr) \
+{ \
+       uint## b ##_t val; \
+       membar_enter(); \
+       val = *ptr; \
+       membar_exit(); \
+       return val; \
+}
+
+atomic_load_n(1, 8)
+atomic_load_n(2, 16)
+atomic_load_n(4, 32)
+#ifdef __HAVE_ATOMIC_CAS_64_UP
+atomic_load_n(8, 64)
+#endif
diff -r 23e26b66b933 -r af0f01d12f52 common/lib/libc/atomic/atomic_store.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/common/lib/libc/atomic/atomic_store.c     Sat Jul 05 20:44:46 2014 +0000
@@ -0,0 +1,52 @@
+/*     $NetBSD: atomic_store.c,v 1.1 2014/07/05 20:44:46 joerg Exp $   */
+
+/*-
+ * Copyright (c) 2014 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
+ * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+ * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
+ * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: atomic_store.c,v 1.1 2014/07/05 20:44:46 joerg Exp $");
+
+#include "atomic_op_namespace.h"
+
+#include <sys/types.h>
+#include <sys/atomic.h>
+
+#define atomic_store_n(n,b) \
+void __atomic_store_ ## n(volatile uint ## b ## _t *, uint ## b ## _t); \
+void \
+__atomic_store_ ## n(volatile uint ## b ## _t *ptr, uint ## b ## _t val) \
+{ \
+       membar_enter(); \
+       *ptr = val; \
+       membar_exit(); \
+}
+
+atomic_store_n(1, 8)
+atomic_store_n(2, 16)
+atomic_store_n(4, 32)
+#ifdef __HAVE_ATOMIC_CAS_64_UP
+atomic_store_n(8, 64)
+#endif