1 files changed, 20 insertions, 0 deletions
diff --git a/gcc-4.9/gcc/testsuite/gcc.dg/atomic-op-optimize.c b/gcc-4.9/gcc/testsuite/gcc.dg/atomic-op-optimize.c
new file mode 100644
index 000000000..d2e960a0c
--- /dev/null
+++ b/gcc-4.9/gcc/testsuite/gcc.dg/atomic-op-optimize.c
@@ -0,0 +1,20 @@
+/* Both these atomic operations should be optimized to an exchange operation.
+   Test that it at happens on x86 by making sure there are 2 xchg's and no
+   compare_exchange loop.  */
+
+/* { dg-require-effective-target sync_int_long } */
+/* { dg-do compile { target { i?86-*-* x86_64-*-* } } } */
+/* { dg-final { scan-assembler-times "cmpxchg" 0 } } */
+/* { dg-final { scan-assembler-times "xchg" 2 } } */
+
+int x;
+
+int f()
+{
+  return __atomic_fetch_and (&x, 0, __ATOMIC_RELAXED);
+}
+
+int g()
+{
+  return __atomic_fetch_or (&x, -1, __ATOMIC_RELAXED);
+}