--- a/src/core/ngx_atomic.h
+++ b/src/core/ngx_atomic.h
@@ -6,9 +6,78 @@
 #include <ngx_core.h>
 
 
+#ifdef __i386__
+
+typedef uint32_t  ngx_atomic_t;
+
+#if (NGX_SMP)
+#define NGX_SMP_LOCK  "lock"
+#else
+#define NGX_SMP_LOCK
+#endif
+
+
+static ngx_inline uint32_t ngx_atomic_inc(ngx_atomic_t *value)
+{
+    uint32_t  old;
+
+    __asm__ __volatile ("
+
+        movl   $1, %0
+    "   NGX_SMP_LOCK
+    "   xaddl  %0, %1
+
+    ": "=a" (old) : "m" (*value));
+
+    return old;
+}
+
+
+static ngx_inline uint32_t ngx_atomic_dec(ngx_atomic_t *value)
+{
+    uint32_t  old;
+
+    __asm__ __volatile ("
+
+        movl   $-1, %0
+    "   NGX_SMP_LOCK
+    "   xaddl  %0, %1
+
+    ": "=a" (old) : "m" (*value));
+
+    return old;
+}
+
+
+static ngx_inline uint32_t ngx_atomic_cmp_set(ngx_atomic_t *lock,
+                                              ngx_atomic_t old,
+                                              ngx_atomic_t set)
+{
+    uint32_t  res;
+
+    __asm__ __volatile ("
+
+    "   NGX_SMP_LOCK
+    "   cmpxchgl  %3, %1
+        setzb     %%al
+        movzbl    %%al, %0
+
+    ": "=a" (res) : "m" (*lock), "a" (old), "q" (set));
+
+    return res;
+}
+
+#else
+
+typedef uint32_t  ngx_atomic_t;
+
 /* STUB */
 #define ngx_atomic_inc(x)   x++;
 #define ngx_atomic_dec(x)   x--;
+#define ngx_atomic_cmp_set(lock, old, set)   1;
+/**/
+
+#endif
 
 
 #endif /* _NGX_ATOMIC_H_INCLUDED_ */