X-Git-Url: http://git.liburcu.org/?p=urcu.git;a=blobdiff_plain;f=compiler.h;h=99972f30e2ba89726f663c78261f4e9203b6d026;hp=fb09ca2b9b238ceec418ba5c21c660b4cebcb7fd;hb=ba59a0c7b244a0939a2298fc76a9002436ef9674;hpb=d8429b11e257939635c5dc4786756effdc38b494

diff --git a/compiler.h b/compiler.h
index fb09ca2..99972f3 100644
--- a/compiler.h
+++ b/compiler.h
@@ -8,23 +8,21 @@
  *
  * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
  *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
-*
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED.  ANY USE IS AT YOUR OWN RISK.
  *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * IBM's contributions to this file may be relicensed under LGPLv2 or later.
+ * Permission is hereby granted to use or copy this program
+ * for any purpose,  provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
  */
 
+#define likely(x)	__builtin_expect(!!(x), 1)
+#define unlikely(x)	__builtin_expect(!!(x), 0)
+
+#define	barrier()	asm volatile("" : : : "memory");
+
 /*
  * Instruct the compiler to perform only a single access to a variable
  * (prohibits merging and refetching). The compiler is also forbidden to reorder
@@ -37,5 +35,16 @@
  * use is to mediate communication between process-level code and irq/NMI
  * handlers, all running on the same CPU.
  */
+#define ACCESS_ONCE(x)	(*(volatile typeof(x) *)&x)
+
+#if (__GNUC__ == 4)
+#define __compiler_offsetof(a, b) __builtin_offsetof(a, b)
+#endif
+
+#ifdef __compiler_offsetof
+#define offsetof(TYPE, MEMBER) __compiler_offsetof(TYPE, MEMBER)
+#else
+#define offsetof(TYPE, MEMBER) ((size_t) &((TYPE *)0)->MEMBER)
+#endif
 
 #endif /* _COMPILER_H */