Merge pull request #2816 from xmcclure/profile-clean-0

[mono.git] / mono / utils / atomic.c

diff --git a/mono/utils/atomic.c b/mono/utils/atomic.c
index 447af4e8995727ef2a353acbeb766b5110127109..b6d1e5f20554000d4b037008ee01dce5e1d5eeba 100644 (file)
--- a/mono/utils/atomic.c
+++ b/mono/utils/atomic.c
@@ -505,8 +505,54 @@ InterlockedCompareExchange64(volatile gint64 *dest, gint64 exch, gint64 comp)
 
 #elif defined (HAVE_64BIT_CMPXCHG_FALLBACK)
 
-#ifdef ENABLE_EXTENSION_MODULE
-#include "../../../mono-extensions/mono/utils/atomic.c"
+#if defined (TARGET_IOS) || defined (TARGET_WATCHOS)
+
+#ifndef __clang__
+#error "Not supported."
+#endif
+
+gint64
+InterlockedCompareExchange64(volatile gint64 *dest, gint64 exch, gint64 comp)
+{
+       return  __sync_val_compare_and_swap (dest, comp, exch);
+}
+
+#elif defined (TARGET_ANDROID)
+
+/* Some Android systems can't find the 64-bit CAS intrinsic at runtime,
+ * so we have to roll our own...
+ */
+
+gint64 InterlockedCompareExchange64(volatile gint64 *dest, gint64 exch, gint64 comp) __attribute__ ((naked));
+
+gint64
+InterlockedCompareExchange64(volatile gint64 *dest, gint64 exch, gint64 comp)
+{
+       __asm__ (
+               "push           {r4, r5, r6, r7}\n"
+               "ldrd           r4, [sp, #16]\n"
+               "dmb            sy\n"
+       "1:\n"
+               "ldrexd         r6, [r0]\n"
+               "cmp            r7, r5\n"
+               "cmpeq          r6, r4\n"
+               "bne            2f\n"
+               "strexd         r1, r2, [r0]\n"
+               "cmp            r1, #0\n"
+               "bne            1b\n"
+       "2:\n"
+               "dmb            sy\n"
+               "mov            r0, r6\n"
+               "mov            r1, r7\n"
+               "pop            {r4, r5, r6, r7}\n"
+               "bx                     lr\n"
+       );
+}
+
+#else
+
+#error "Need a 64-bit CAS fallback!"
+
 #endif
 
 #else