[src/trunk]: src/common/lib/libc/atomic Provide __atomic_compare_exchange_N (...

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

details:   https://anonhg.NetBSD.org/src/rev/fd57712ac474
branches:  trunk
changeset: 803099:fd57712ac474
user:      martin <martin%NetBSD.org@localhost>
date:      Sun Oct 12 17:51:47 2014 +0000

description:
Provide __atomic_compare_exchange_N (as needed for the C11 2011 <atomic>
ops) via the corresponding CAS.

diffstat:

 common/lib/libc/atomic/atomic_c11_compare_exchange_cas_16.c |  52 +++++++++++++
 common/lib/libc/atomic/atomic_c11_compare_exchange_cas_32.c |  52 +++++++++++++
 common/lib/libc/atomic/atomic_c11_compare_exchange_cas_8.c  |  52 +++++++++++++
 3 files changed, 156 insertions(+), 0 deletions(-)

diffs (168 lines):

diff -r 7d834a56f752 -r fd57712ac474 common/lib/libc/atomic/atomic_c11_compare_exchange_cas_16.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/common/lib/libc/atomic/atomic_c11_compare_exchange_cas_16.c       Sun Oct 12 17:51:47 2014 +0000
@@ -0,0 +1,52 @@
+/*     $NetBSD: atomic_c11_compare_exchange_cas_16.c,v 1.1 2014/10/12 17:51:47 martin Exp $    */
+
+/*-
+ * Copyright (c) 2007 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Martin Husemann.
+ *
+ * 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 "atomic_op_namespace.h"
+
+#if !defined(_KERNEL) && !defined(_STANDALONE)
+#include <stdbool.h>
+#endif
+#include <sys/atomic.h>
+
+bool
+__atomic_compare_exchange_2(volatile uint16_t *mem,
+    uint16_t *expected, uint16_t desired,
+    bool weak, int success, int failure)
+{
+       uint16_t old = *expected;
+
+       /*
+        * Ignore the details (weak, memory model on success and failure)
+        * and just do the cas. If we get here the compiler couldn't
+        * do better and it mostly will not matter at all.
+        */
+       return atomic_cas_16(mem, old, desired) == old;
+}
diff -r 7d834a56f752 -r fd57712ac474 common/lib/libc/atomic/atomic_c11_compare_exchange_cas_32.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/common/lib/libc/atomic/atomic_c11_compare_exchange_cas_32.c       Sun Oct 12 17:51:47 2014 +0000
@@ -0,0 +1,52 @@
+/*     $NetBSD: atomic_c11_compare_exchange_cas_32.c,v 1.1 2014/10/12 17:51:47 martin Exp $    */
+
+/*-
+ * Copyright (c) 2007 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Martin Husemann.
+ *
+ * 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 "atomic_op_namespace.h"
+
+#if !defined(_KERNEL) && !defined(_STANDALONE)
+#include <stdbool.h>
+#endif
+#include <sys/atomic.h>
+
+bool
+__atomic_compare_exchange_4(volatile uint32_t *mem,
+    uint32_t *expected, uint32_t desired,
+    bool weak, int success, int failure)
+{
+       uint32_t old = *expected;
+
+       /*
+        * Ignore the details (weak, memory model on success and failure)
+        * and just do the cas. If we get here the compiler couldn't
+        * do better and it mostly will not matter at all.
+        */
+       return atomic_cas_32(mem, old, desired) == old;
+}
diff -r 7d834a56f752 -r fd57712ac474 common/lib/libc/atomic/atomic_c11_compare_exchange_cas_8.c
--- /dev/null   Thu Jan 01 00:00:00 1970 +0000
+++ b/common/lib/libc/atomic/atomic_c11_compare_exchange_cas_8.c        Sun Oct 12 17:51:47 2014 +0000
@@ -0,0 +1,52 @@
+/*     $NetBSD: atomic_c11_compare_exchange_cas_8.c,v 1.1 2014/10/12 17:51:47 martin Exp $     */
+
+/*-
+ * Copyright (c) 2007 The NetBSD Foundation, Inc.
+ * All rights reserved.
+ *
+ * This code is derived from software contributed to The NetBSD Foundation
+ * by Martin Husemann.
+ *
+ * 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 "atomic_op_namespace.h"
+
+#if !defined(_KERNEL) && !defined(_STANDALONE)
+#include <stdbool.h>
+#endif
+#include <sys/atomic.h>
+
+bool
+__atomic_compare_exchange_1(volatile uint8_t *mem,
+    uint8_t *expected, uint8_t desired,
+    bool weak, int success, int failure)
+{
+       uint8_t old = *expected;
+
+       /*
+        * Ignore the details (weak, memory model on success and failure)
+        * and just do the cas. If we get here the compiler couldn't
+        * do better and it mostly will not matter at all.
+        */
+       return atomic_cas_8(mem, old, desired) == old;
+}