--- libeio/ecb.h	2011/08/03 15:25:38	1.7
+++ libeio/ecb.h	2011/08/21 01:03:09	1.8
@@ -50,7 +50,7 @@
 
 /* many compilers define _GNUC_ to some versions but then only implement
  * what their idiot authors think are the "more important" extensions,
- * causing enourmous grief in return for some better fake benchmark numbers.
+ * causing enormous grief in return for some better fake benchmark numbers.
  * or so.
  * we try to detect these and simply assume they are not gcc - if they have
  * an issue with that they should have done it right in the first place.
@@ -65,6 +65,13 @@
 
 /*****************************************************************************/
 
+/* ECB_NO_THREADS - ecb is not used by multiple threads, ever */
+/* ECB_NO_SMP     - ecb might be used in multiple threads, but only on a single cpu */
+
+#if ECB_NO_THREADS || ECB_NO_SMP
+  #define ECB_MEMORY_FENCE do { } while (0)
+#endif
+
 #ifndef ECB_MEMORY_FENCE
   #if ECB_GCC_VERSION(2,5)
     #if __x86
@@ -75,15 +82,23 @@
       #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("mfence" : : : "memory")
       #define ECB_MEMORY_FENCE_ACQUIRE __asm__ __volatile__ ("lfence" : : : "memory")
       #define ECB_MEMORY_FENCE_RELEASE __asm__ __volatile__ ("sfence") /* play safe - not needed in any current cpu */
+    #elif __powerpc__ || __ppc__ || __powerpc64__ || __ppc64__
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("sync" : : : "memory")
+    #elif defined(__ARM_ARCH_6__ ) || defined(__ARM_ARCH_6J__ ) \
+       || defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6ZK__)
+      #define ECB_MEMORY_FENCE __asm__ __volatile__ ("mcr p15,0,%0,c7,c10,5" : : "r" (0) : "memory")
+    #elif defined(__ARM_ARCH_7__ ) || defined(__ARM_ARCH_7A__ ) \
+       || defined(__ARM_ARCH_7M__) || defined(__ARM_ARCH_7R__ )
+      #define ECB_MEMORY_FENCE         __asm__ __volatile__ ("dmb" : : : "memory")
     #endif
   #endif
 #endif
 
 #ifndef ECB_MEMORY_FENCE
-  #if ECB_GCC_VERSION(4,4)
+  #if ECB_GCC_VERSION(4,4) || defined(__INTEL_COMPILER)
     #define ECB_MEMORY_FENCE         __sync_synchronize ()
-    #define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); })
-    #define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release      (&dummy   ); })
+    /*#define ECB_MEMORY_FENCE_ACQUIRE ({ char dummy = 0; __sync_lock_test_and_set (&dummy, 1); }) */
+    /*#define ECB_MEMORY_FENCE_RELEASE ({ char dummy = 1; __sync_lock_release      (&dummy   ); }) */
   #elif _MSC_VER >= 1400 /* VC++ 2005 */
     #pragma intrinsic(_ReadBarrier,_WriteBarrier,_ReadWriteBarrier)
     #define ECB_MEMORY_FENCE         _ReadWriteBarrier ()
@@ -92,24 +107,32 @@
   #elif defined(_WIN32)
     #include <WinNT.h>
     #define ECB_MEMORY_FENCE         MemoryBarrier () /* actually just xchg on x86... scary */
-    #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
-    #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
   #endif
 #endif
 
 #ifndef ECB_MEMORY_FENCE
-  /*
-   * if you get undefined symbol references to pthread_mutex_lock,
-   * or failure to find pthread.h, then you should implement
-   * the ECB_MEMORY_FENCE operations for your cpu/compiler
-   * OR proide pthread.h and link against the posix thread library
-   * of your system.
-   */
-  #include <pthread.h>
+  #if !ECB_AVOID_PTHREADS
+    /*
+     * if you get undefined symbol references to pthread_mutex_lock,
+     * or failure to find pthread.h, then you should implement
+     * the ECB_MEMORY_FENCE operations for your cpu/compiler
+     * OR provide pthread.h and link against the posix thread library
+     * of your system.
+     */
+    #include <pthread.h>
+    #define ECB_NEEDS_PTHREADS 1
+    #define ECB_MEMORY_FENCE_NEEDS_PTHREADS 1
+
+    static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
+    #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
+  #endif
+#endif
 
-  static pthread_mutex_t ecb_mf_lock = PTHREAD_MUTEX_INITIALIZER;
-  #define ECB_MEMORY_FENCE do { pthread_mutex_lock (&ecb_mf_lock); pthread_mutex_unlock (&ecb_mf_lock); } while (0)
+#if !defined(ECB_MEMORY_FENCE_ACQUIRE) && defined(ECB_MEMORY_FENCE)
   #define ECB_MEMORY_FENCE_ACQUIRE ECB_MEMORY_FENCE
+#endif
+
+#if !defined(ECB_MEMORY_FENCE_RELEASE) && defined(ECB_MEMORY_FENCE)
   #define ECB_MEMORY_FENCE_RELEASE ECB_MEMORY_FENCE
 #endif
 
@@ -243,9 +266,6 @@
     return x >> 24;
   }
 
-  /* you have the choice beetween something with a table lookup, */
-  /* something using lots of bit arithmetic and a simple loop */
-  /* we went for the loop */
   ecb_function_ int ecb_ld32 (uint32_t x) ecb_const;
   ecb_function_ int ecb_ld32 (uint32_t x)
   {