[Boost-commit] svn:boost r79520 - trunk/boost/asio/detail

Subject: [Boost-commit] svn:boost r79520 - trunk/boost/asio/detail
From: chris_at_[hidden]
Date: 2012-07-15 00:18:38

Author: chris_kohlhoff
Date: 2012-07-15 00:18:37 EDT (Sun, 15 Jul 2012)
New Revision: 79520
URL: http://svn.boost.org/trac/boost/changeset/79520

Log:
Use SSE2 load and store fences.
Text files modified: 
   trunk/boost/asio/detail/gcc_x86_fenced_block.hpp |    21 +++++++++++++++------                   
   1 files changed, 15 insertions(+), 6 deletions(-)

Modified: trunk/boost/asio/detail/gcc_x86_fenced_block.hpp
==============================================================================
--- trunk/boost/asio/detail/gcc_x86_fenced_block.hpp	(original)
+++ trunk/boost/asio/detail/gcc_x86_fenced_block.hpp	2012-07-15 00:18:37 EDT (Sun, 15 Jul 2012)
@@ -40,17 +40,17 @@
   // Constructor for a full fenced block.
   explicit gcc_x86_fenced_block(full_t)
   {
-    barrier1();
+    lbarrier();
   }
 
   // Destructor.
   ~gcc_x86_fenced_block()
   {
-    barrier2();
+    sbarrier();
   }
 
 private:
-  static int barrier1()
+  static int barrier()
   {
     int r = 0, m = 1;
     __asm__ __volatile__ (
@@ -61,12 +61,21 @@
     return r;
   }
 
-  static void barrier2()
+  static void lbarrier()
   {
 #if defined(__SSE2__)
-    __asm__ __volatile__ ("mfence" ::: "memory");
+    __asm__ __volatile__ ("lfence" ::: "memory");
 #else // defined(__SSE2__)
-    barrier1();
+    barrier();
+#endif // defined(__SSE2__)
+  }
+
+  static void sbarrier()
+  {
+#if defined(__SSE2__)
+    __asm__ __volatile__ ("sfence" ::: "memory");
+#else // defined(__SSE2__)
+    barrier();
 #endif // defined(__SSE2__)
   }
 };