Revert "Rewrite atomic.h to use stdatomic.h."

This reverts commit cb344d464009337c283431dec4441b70481d1a49.

Change-Id: Ib17cd8d00695062177ce863cedc4ec7148012317
diff --git a/include/cutils/atomic-arm.h b/include/cutils/atomic-arm.h
new file mode 100644
index 0000000..6b031b6
--- /dev/null
+++ b/include/cutils/atomic-arm.h
@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed 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.
+ */
+
+#ifndef ANDROID_CUTILS_ATOMIC_ARM_H
+#define ANDROID_CUTILS_ATOMIC_ARM_H
+
+#include <stdint.h>
+
+#ifndef ANDROID_ATOMIC_INLINE
+#define ANDROID_ATOMIC_INLINE inline __attribute__((always_inline))
+#endif
+
+extern ANDROID_ATOMIC_INLINE void android_compiler_barrier()
+{
+    __asm__ __volatile__ ("" : : : "memory");
+}
+
+extern ANDROID_ATOMIC_INLINE void android_memory_barrier()
+{
+#if ANDROID_SMP == 0
+    android_compiler_barrier();
+#else
+    __asm__ __volatile__ ("dmb" : : : "memory");
+#endif
+}
+
+extern ANDROID_ATOMIC_INLINE
+int32_t android_atomic_acquire_load(volatile const int32_t *ptr)
+{
+    int32_t value = *ptr;
+    android_memory_barrier();
+    return value;
+}
+
+extern ANDROID_ATOMIC_INLINE
+int32_t android_atomic_release_load(volatile const int32_t *ptr)
+{
+    android_memory_barrier();
+    return *ptr;
+}
+
+extern ANDROID_ATOMIC_INLINE
+void android_atomic_acquire_store(int32_t value, volatile int32_t *ptr)
+{
+    *ptr = value;
+    android_memory_barrier();
+}
+
+extern ANDROID_ATOMIC_INLINE
+void android_atomic_release_store(int32_t value, volatile int32_t *ptr)
+{
+    android_memory_barrier();
+    *ptr = value;
+}
+
+extern ANDROID_ATOMIC_INLINE
+int android_atomic_cas(int32_t old_value, int32_t new_value,
+                       volatile int32_t *ptr)
+{
+    int32_t prev, status;
+    do {
+        __asm__ __volatile__ ("ldrex %0, [%3]\n"
+                              "mov %1, #0\n"
+                              "teq %0, %4\n"
+#ifdef __thumb2__
+                              "it eq\n"
+#endif
+                              "strexeq %1, %5, [%3]"
+                              : "=&r" (prev), "=&r" (status), "+m"(*ptr)
+                              : "r" (ptr), "Ir" (old_value), "r" (new_value)
+                              : "cc");
+    } while (__builtin_expect(status != 0, 0));
+    return prev != old_value;
+}
+
+extern ANDROID_ATOMIC_INLINE
+int android_atomic_acquire_cas(int32_t old_value, int32_t new_value,
+                               volatile int32_t *ptr)
+{
+    int status = android_atomic_cas(old_value, new_value, ptr);
+    android_memory_barrier();
+    return status;
+}
+
+extern ANDROID_ATOMIC_INLINE
+int android_atomic_release_cas(int32_t old_value, int32_t new_value,
+                               volatile int32_t *ptr)
+{
+    android_memory_barrier();
+    return android_atomic_cas(old_value, new_value, ptr);
+}
+
+extern ANDROID_ATOMIC_INLINE
+int32_t android_atomic_add(int32_t increment, volatile int32_t *ptr)
+{
+    int32_t prev, tmp, status;
+    android_memory_barrier();
+    do {
+        __asm__ __volatile__ ("ldrex %0, [%4]\n"
+                              "add %1, %0, %5\n"
+                              "strex %2, %1, [%4]"
+                              : "=&r" (prev), "=&r" (tmp),
+                                "=&r" (status), "+m" (*ptr)
+                              : "r" (ptr), "Ir" (increment)
+                              : "cc");
+    } while (__builtin_expect(status != 0, 0));
+    return prev;
+}
+
+extern ANDROID_ATOMIC_INLINE int32_t android_atomic_inc(volatile int32_t *addr)
+{
+    return android_atomic_add(1, addr);
+}
+
+extern ANDROID_ATOMIC_INLINE int32_t android_atomic_dec(volatile int32_t *addr)
+{
+    return android_atomic_add(-1, addr);
+}
+
+extern ANDROID_ATOMIC_INLINE
+int32_t android_atomic_and(int32_t value, volatile int32_t *ptr)
+{
+    int32_t prev, tmp, status;
+    android_memory_barrier();
+    do {
+        __asm__ __volatile__ ("ldrex %0, [%4]\n"
+                              "and %1, %0, %5\n"
+                              "strex %2, %1, [%4]"
+                              : "=&r" (prev), "=&r" (tmp),
+                                "=&r" (status), "+m" (*ptr)
+                              : "r" (ptr), "Ir" (value)
+                              : "cc");
+    } while (__builtin_expect(status != 0, 0));
+    return prev;
+}
+
+extern ANDROID_ATOMIC_INLINE
+int32_t android_atomic_or(int32_t value, volatile int32_t *ptr)
+{
+    int32_t prev, tmp, status;
+    android_memory_barrier();
+    do {
+        __asm__ __volatile__ ("ldrex %0, [%4]\n"
+                              "orr %1, %0, %5\n"
+                              "strex %2, %1, [%4]"
+                              : "=&r" (prev), "=&r" (tmp),
+                                "=&r" (status), "+m" (*ptr)
+                              : "r" (ptr), "Ir" (value)
+                              : "cc");
+    } while (__builtin_expect(status != 0, 0));
+    return prev;
+}
+
+#endif /* ANDROID_CUTILS_ATOMIC_ARM_H */