Add atomic and bswap functions to libcompiler_rt

There have been several mentions on our mailing lists about missing
atomic functions in our system libraries (e.g. __atomic_load_8 and
friends), and recently I saw __bswapdi2 and __bswapsi2 mentioned too.

To address this, add implementations for the functions from compiler-rt
to the system compiler support libraries, e.g. libcompiler_rt.a and and
libgcc_s.so.

This also needs a small fixup in compiler-rt's atomic.c, to ensure that
32-bit mips can build correctly.

Bump __FreeBSD_version to make it easier for port maintainers to detect
when these functions were added.

MFC after:	2 weeks
Differential Revision: https://reviews.freebsd.org/D26159

1 files changed, 2 insertions, 2 deletions

diff --git a/contrib/llvm-project/compiler-rt/lib/builtins/atomic.c b/contrib/llvm-project/compiler-rt/lib/builtins/atomic.c
index 2a69101fbcee..84d116a36cd9 100644
--- a/contrib/llvm-project/compiler-rt/lib/builtins/atomic.c
+++ b/contrib/llvm-project/compiler-rt/lib/builtins/atomic.c
@@ -125,8 +125,8 @@ static __inline Lock *lock_for_pointer(void *ptr) {
 #define IS_LOCK_FREE_2 __c11_atomic_is_lock_free(2)
 #define IS_LOCK_FREE_4 __c11_atomic_is_lock_free(4)
 
-/// 32 bit PowerPC doesn't support 8-byte lock_free atomics
-#if !defined(__powerpc64__) && defined(__powerpc__)
+/// 32 bit MIPS and PowerPC don't support 8-byte lock_free atomics
+#if defined(__mips__) || (!defined(__powerpc64__) && defined(__powerpc__))
 #define IS_LOCK_FREE_8 0
 #else
 #define IS_LOCK_FREE_8 __c11_atomic_is_lock_free(8)