1 files changed, 57 insertions, 0 deletions
diff --git a/libjava/sysdep/aarch64/locks.h b/libjava/sysdep/aarch64/locks.h
new file mode 100644
index 00000000000..f91473d08c7
--- /dev/null
+++ b/libjava/sysdep/aarch64/locks.h
@@ -0,0 +1,57 @@
+// locks.h - Thread synchronization primitives. AArch64 implementation.
+
+#ifndef __SYSDEP_LOCKS_H__
+#define __SYSDEP_LOCKS_H__
+
+typedef size_t obj_addr_t;	/* Integer type big enough for object	*/
+				/* address.				*/
+
+// Atomically replace *addr by new_val if it was initially equal to old.
+// Return true if the comparison succeeded.
+// Assumed to have acquire semantics, i.e. later memory operations
+// cannot execute before the compare_and_swap finishes.
+inline static bool
+compare_and_swap(volatile obj_addr_t *addr,
+                 obj_addr_t old,
+                 obj_addr_t new_val)
+{
+  return __sync_bool_compare_and_swap(addr, old, new_val);
+}
+
+// Set *addr to new_val with release semantics, i.e. making sure
+// that prior loads and stores complete before this
+// assignment.
+inline static void
+release_set(volatile obj_addr_t *addr, obj_addr_t new_val)
+{
+  __sync_synchronize();
+  *addr = new_val;
+}
+
+// Compare_and_swap with release semantics instead of acquire semantics.
+// On many architecture, the operation makes both guarantees, so the
+// implementation can be the same.
+inline static bool
+compare_and_swap_release(volatile obj_addr_t *addr,
+			 obj_addr_t old,
+			 obj_addr_t new_val)
+{
+  return __sync_bool_compare_and_swap(addr, old, new_val);
+}
+
+// Ensure that subsequent instructions do not execute on stale
+// data that was loaded from memory before the barrier.
+inline static void
+read_barrier()
+{
+  __sync_synchronize();
+}
+
+// Ensure that prior stores to memory are completed with respect to other
+// processors.
+inline static void
+write_barrier()
+{
+  __sync_synchronize();
+}
+#endif