builtins: Implement the functions from stdatomic.h

Talking to John and Doug, we concluded that these functions from
stdatomic really do belong here in compiler-rt rather than in libc,
since the compiler owns stdatomic.h and these need to refer to
clang-specific builtins. Nonetheless, I've only added these on darwin
for now - other platforms should probably do the same unless their
libc does implement these functions.

llvm-svn: 236805

6 files changed, 116 insertions, 0 deletions

diff --git a/compiler-rt/lib/builtins/atomic_flag_clear.c b/compiler-rt/lib/builtins/atomic_flag_clear.c
new file mode 100644
index 00000000000..15984cd5267
--- /dev/null
+++ b/compiler-rt/lib/builtins/atomic_flag_clear.c
@@ -0,0 +1,19 @@
+/*===-- atomic_flag_clear.c -------------------------------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------===
+ *
+ * This file implements atomic_flag_clear from C11's stdatomic.h.
+ *
+ *===------------------------------------------------------------------------===
+ */
+
+#include <stdatomic.h>
+#undef atomic_flag_clear
+void atomic_flag_clear(volatile atomic_flag *object) {
+  return __c11_atomic_store(&(object)->_Value, 0, __ATOMIC_SEQ_CST);
+}
diff --git a/compiler-rt/lib/builtins/atomic_flag_clear_explicit.c b/compiler-rt/lib/builtins/atomic_flag_clear_explicit.c
new file mode 100644
index 00000000000..0f7859c2cd8
--- /dev/null
+++ b/compiler-rt/lib/builtins/atomic_flag_clear_explicit.c
@@ -0,0 +1,20 @@
+/*===-- atomic_flag_clear_explicit.c ----------------------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------===
+ *
+ * This file implements atomic_flag_clear_explicit from C11's stdatomic.h.
+ *
+ *===------------------------------------------------------------------------===
+ */
+
+#include <stdatomic.h>
+#undef atomic_flag_clear_explicit
+void atomic_flag_clear_explicit(volatile atomic_flag *object,
+                                memory_order order) {
+  return __c11_atomic_store(&(object)->_Value, 0, order);
+}
diff --git a/compiler-rt/lib/builtins/atomic_flag_test_and_set.c b/compiler-rt/lib/builtins/atomic_flag_test_and_set.c
new file mode 100644
index 00000000000..07209fc02d5
--- /dev/null
+++ b/compiler-rt/lib/builtins/atomic_flag_test_and_set.c
@@ -0,0 +1,19 @@
+/*===-- atomic_flag_test_and_set.c ------------------------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------===
+ *
+ * This file implements atomic_flag_test_and_set from C11's stdatomic.h.
+ *
+ *===------------------------------------------------------------------------===
+ */
+
+#include <stdatomic.h>
+#undef atomic_flag_test_and_set
+_Bool atomic_flag_test_and_set(volatile atomic_flag *object) {
+  return __c11_atomic_exchange(&(object)->_Value, 1, __ATOMIC_SEQ_CST);
+}
diff --git a/compiler-rt/lib/builtins/atomic_flag_test_and_set_explicit.c b/compiler-rt/lib/builtins/atomic_flag_test_and_set_explicit.c
new file mode 100644
index 00000000000..eaa5be08df4
--- /dev/null
+++ b/compiler-rt/lib/builtins/atomic_flag_test_and_set_explicit.c
@@ -0,0 +1,20 @@
+/*===-- atomic_flag_test_and_set_explicit.c ---------------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------===
+ *
+ * This file implements atomic_flag_test_and_set_explicit from C11's stdatomic.h
+ *
+ *===------------------------------------------------------------------------===
+ */
+
+#include <stdatomic.h>
+#undef atomic_flag_test_and_set_explicit
+_Bool atomic_flag_test_and_set_explicit(volatile atomic_flag *object,
+                                        memory_order order) {
+  return __c11_atomic_exchange(&(object)->_Value, 1, order);
+}
diff --git a/compiler-rt/lib/builtins/atomic_signal_fence.c b/compiler-rt/lib/builtins/atomic_signal_fence.c
new file mode 100644
index 00000000000..ad292d2f1c7
--- /dev/null
+++ b/compiler-rt/lib/builtins/atomic_signal_fence.c
@@ -0,0 +1,19 @@
+/*===-- atomic_signal_fence.c -----------------------------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------===
+ *
+ * This file implements atomic_signal_fence from C11's stdatomic.h.
+ *
+ *===------------------------------------------------------------------------===
+ */
+
+#include <stdatomic.h>
+#undef atomic_signal_fence
+void atomic_signal_fence(memory_order order) {
+  __c11_atomic_signal_fence(order);
+}
diff --git a/compiler-rt/lib/builtins/atomic_thread_fence.c b/compiler-rt/lib/builtins/atomic_thread_fence.c
new file mode 100644
index 00000000000..71f698c9de7
--- /dev/null
+++ b/compiler-rt/lib/builtins/atomic_thread_fence.c
@@ -0,0 +1,19 @@
+/*===-- atomic_thread_fence.c -----------------------------------------------===
+ *
+ *                     The LLVM Compiler Infrastructure
+ *
+ * This file is dual licensed under the MIT and the University of Illinois Open
+ * Source Licenses. See LICENSE.TXT for details.
+ *
+ *===------------------------------------------------------------------------===
+ *
+ * This file implements atomic_thread_fence from C11's stdatomic.h.
+ *
+ *===------------------------------------------------------------------------===
+ */
+
+#include <stdatomic.h>
+#undef atomic_thread_fence
+void atomic_thread_fence(memory_order order) {
+  __c11_atomic_thread_fence(order);
+}