Use asm instead of _mm_pause for non-SSE CPUs.

cybozu · Jan 17, 2014 · 7a0b4f6 · 7a0b4f6
1 parent efd6021
commit 7a0b4f6
Showing 1 changed file with 4 additions and 0 deletions.
diff --git a/cybozu/spinlock.hpp b/cybozu/spinlock.hpp
@@ -27,7 +27,11 @@ class spinlock {
     std::atomic_flag m_flag;
     void pause() {
 #if defined(__i386__) || defined(__x86_64__)
+# if defined(__SSE__)
         _mm_pause();
+# else
+        __asm__ __volatile__ ("rep; nop");
+# endif
 #endif
     }
 };