--- a/hotspot/src/os_cpu/solaris_x86/vm/atomic_solaris_x86.inline.hpp	Tue Nov 18 12:33:47 2014 +0000
+++ b/hotspot/src/os_cpu/solaris_x86/vm/atomic_solaris_x86.inline.hpp	Tue Oct 21 15:07:25 2014 +0200
@@ -68,6 +68,8 @@
 extern "C" {
   jint _Atomic_add(jint add_value, volatile jint* dest IS_MP_DECL());
   jint _Atomic_xchg(jint exchange_value, volatile jint* dest);
+  jbyte _Atomic_cmpxchg_byte(jbyte exchange_value, volatile jbyte* dest,
+                       jbyte compare_value IS_MP_DECL());
   jint _Atomic_cmpxchg(jint exchange_value, volatile jint* dest,
                        jint compare_value IS_MP_DECL());
   jlong _Atomic_cmpxchg_long(jlong exchange_value, volatile jlong* dest,
@@ -82,6 +84,11 @@
   return _Atomic_xchg(exchange_value, dest);
 }
 
+#define VM_HAS_SPECIALIZED_CMPXCHG_BYTE
+inline jbyte    Atomic::cmpxchg    (jbyte    exchange_value, volatile jbyte*    dest, jbyte    compare_value) {
+  return _Atomic_cmpxchg_byte(exchange_value, dest, compare_value IS_MP_ARG());
+}
+
 inline jint     Atomic::cmpxchg    (jint     exchange_value, volatile jint*     dest, jint     compare_value) {
   return _Atomic_cmpxchg(exchange_value, dest, compare_value IS_MP_ARG());
 }
@@ -217,6 +224,15 @@
     return exchange_value;
   }
 
+
+  inline jbyte _Atomic_cmpxchg_byte(jbyte exchange_value, volatile jbyte* dest, jbyte compare_value, int mp) {
+    __asm__ volatile (LOCK_IF_MP(%4) "cmpxchgb %1,(%3)"
+                    : "=a" (exchange_value)
+                    : "q" (exchange_value), "a" (compare_value), "r" (dest), "r" (mp)
+                    : "cc", "memory");
+    return exchange_value;
+  }
+
   // This is the interface to the atomic instruction in solaris_i486.s.
   jlong _Atomic_cmpxchg_long_gcc(jlong exchange_value, volatile jlong* dest, jlong compare_value, int mp);