New apr_atomic implementation for S/390 native atomic operations.

Tested on: RHEL AS 4 (Nahant Update 4), IBM/S390, running under VM (64 bit mode), gcc 3.4.6


git-svn-id: http://svn.apache.org/repos/asf/apr/apr/trunk@554095 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 132 insertions, 0 deletions

diff --git a/atomic/unix/s390.c b/atomic/unix/s390.c
new file mode 100644
index 000000000..a81ffdd16
--- /dev/null
+++ b/atomic/unix/s390.c
@@ -0,0 +1,132 @@
+/* Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements.  See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License.  You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "apr_arch_atomic.h"
+
+#ifdef USE_ATOMICS_S390
+
+APR_DECLARE(apr_status_t) apr_atomic_init(apr_pool_t *p)
+{
+    return APR_SUCCESS;
+}
+
+APR_DECLARE(apr_uint32_t) apr_atomic_read32(volatile apr_uint32_t *mem)
+{
+    return *mem;
+}
+
+APR_DECLARE(void) apr_atomic_set32(volatile apr_uint32_t *mem, apr_uint32_t val)
+{
+    *mem = val;
+}
+
+static APR_INLINE apr_uint32_t atomic_add(volatile apr_uint32_t *mem, apr_uint32_t val)
+{
+    apr_uint32_t prev = *mem, temp;
+
+    asm volatile ("loop_%=:\n"
+                  "	lr  %1,%0\n"
+                  "	alr %1,%3\n"
+                  "	cs  %0,%1,%2\n"
+                  "	jl  loop_%=\n"
+                  : "+d" (prev), "+d" (temp), "=Q" (*mem)
+                  : "d" (val), "m" (*mem)
+                  : "cc", "memory");
+
+    return prev;
+}
+
+APR_DECLARE(apr_uint32_t) apr_atomic_add32(volatile apr_uint32_t *mem, apr_uint32_t val)
+{
+    return atomic_add(mem, val);
+}
+
+APR_DECLARE(apr_uint32_t) apr_atomic_inc32(volatile apr_uint32_t *mem)
+{
+    return atomic_add(mem, 1);
+}
+
+static APR_INLINE apr_uint32_t atomic_sub(volatile apr_uint32_t *mem, apr_uint32_t val)
+{
+    apr_uint32_t prev = *mem, temp;
+
+    asm volatile ("loop_%=:\n"
+                  "	lr  %1,%0\n"
+                  "	slr %1,%3\n"
+                  "	cs  %0,%1,%2\n"
+                  "	jl  loop_%=\n"
+                  : "+d" (prev), "+d" (temp), "=Q" (*mem)
+                  : "d" (val), "m" (*mem)
+                  : "cc", "memory");
+
+    return temp;
+}
+
+APR_DECLARE(void) apr_atomic_sub32(volatile apr_uint32_t *mem, apr_uint32_t val)
+{
+    atomic_sub(mem, val);
+}
+
+APR_DECLARE(int) apr_atomic_dec32(volatile apr_uint32_t *mem)
+{
+    return atomic_sub(mem, 1);
+}
+
+APR_DECLARE(apr_uint32_t) apr_atomic_cas32(volatile apr_uint32_t *mem, apr_uint32_t with,
+                                           apr_uint32_t cmp)
+{
+    asm volatile ("	cs  %0,%2,%1\n"
+                  : "+d" (cmp), "=Q" (*mem)
+                  : "d" (with), "m" (*mem)
+                  : "cc", "memory");
+
+    return cmp;
+}
+
+APR_DECLARE(apr_uint32_t) apr_atomic_xchg32(volatile apr_uint32_t *mem, apr_uint32_t val)
+{
+    apr_uint32_t prev = *mem;
+
+    asm volatile ("loop_%=:\n"
+                  "	cs  %0,%2,%1\n"
+                  "	jl  loop_%=\n"
+                  : "+d" (prev), "=Q" (*mem)
+                  : "d" (val), "m" (*mem)
+                  : "cc", "memory");
+
+    return prev;
+}
+
+APR_DECLARE(void*) apr_atomic_casptr(volatile void **mem, void *with, const void *cmp)
+{
+    void *prev = (void *) cmp;
+#if APR_SIZEOF_VOIDP == 4
+    asm volatile ("	cs  %0,%2,%1\n"
+                  : "+d" (prev), "=Q" (*mem)
+                  : "d" (with), "m" (*mem)
+                  : "cc", "memory");
+#elif APR_SIZEOF_VOIDP == 8
+    asm volatile ("	csg %0,%2,%1\n"
+                  : "+d" (prev), "=Q" (*mem)
+                  : "d" (with), "m" (*mem)
+                  : "cc", "memory");
+#else
+#error APR_SIZEOF_VOIDP value not supported
+#endif
+    return prev;
+}
+
+#endif /* USE_ATOMICS_S390 */