X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=include%2Furcu%2Fcompiler.h;h=887d9be1d3f1e8ee492d225412ba884a1c79428b;hb=d18544842bdfbf2cba6c194a8e8d305ddf5e295e;hp=157346763078a3ec1d73b7c65618ed1bd98b325f;hpb=2875743718fb23293190b5edd0f2b530977270b1;p=urcu.git

diff --git a/include/urcu/compiler.h b/include/urcu/compiler.h
index 1573467..887d9be 100644
--- a/include/urcu/compiler.h
+++ b/include/urcu/compiler.h
@@ -1,30 +1,30 @@
+// SPDX-FileCopyrightText: 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
+//
+// SPDX-License-Identifier: LGPL-2.1-or-later
+
 #ifndef _URCU_COMPILER_H
 #define _URCU_COMPILER_H
 
 /*
- * compiler.h
- *
  * Compiler definitions.
- *
- * Copyright (c) 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to deal
- * in the Software without restriction, including without limitation the rights
- * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
- * copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
  */
 
 #include <stddef.h>	/* for offsetof */
 
+#if defined __cplusplus
+# include <type_traits>	/* for std::remove_cv */
+#endif
+
+#include <urcu/config.h>
+
 #define caa_likely(x)	__builtin_expect(!!(x), 1)
 #define caa_unlikely(x)	__builtin_expect(!!(x), 0)
 
-#define	cmm_barrier()	__asm__ __volatile__ ("" : : : "memory")
+#ifdef CONFIG_RCU_USE_ATOMIC_BUILTINS
+#  define cmm_barrier() __atomic_signal_fence(__ATOMIC_SEQ_CST)
+#else
+#  define cmm_barrier() __asm__ __volatile__ ("" : : : "memory")
+#endif
 
 /*
  * Instruct the compiler to perform only a single access to a variable
@@ -70,6 +70,23 @@
 		(type *)((char *)__ptr - offsetof(type, member));	\
 	})
 
+/*
+ * caa_container_of_check_null - Get the address of an object containing a field.
+ *
+ * @ptr: pointer to the field.
+ * @type: type of the object.
+ * @member: name of the field within the object.
+ *
+ * Return the address of the object containing the field. Return NULL if
+ * @ptr is NULL.
+ */
+#define caa_container_of_check_null(ptr, type, member)			\
+	__extension__							\
+	({								\
+		const __typeof__(((type *) NULL)->member) * __ptr = (ptr); \
+		(__ptr) ? (type *)((char *)__ptr - offsetof(type, member)) : NULL; \
+	})
+
 #define CAA_BUILD_BUG_ON_ZERO(cond) (sizeof(struct { int:-!!(cond); }))
 #define CAA_BUILD_BUG_ON(cond) ((void)CAA_BUILD_BUG_ON_ZERO(cond))
 
@@ -82,7 +99,7 @@
 #define __rcu
 
 #ifdef __cplusplus
-#define URCU_FORCE_CAST(type, arg)	(reinterpret_cast<type>(arg))
+#define URCU_FORCE_CAST(_type, arg)	(reinterpret_cast<std::remove_cv<_type>::type>(arg))
 #else
 #define URCU_FORCE_CAST(type, arg)	((type) (arg))
 #endif
@@ -119,10 +136,61 @@
 				+ __GNUC_PATCHLEVEL__)
 #endif
 
-#ifndef __cplusplus
-#define caa_c_transparent_union	__attribute__((__transparent_union__))
+#ifdef __cplusplus
+#define caa_unqual_scalar_typeof(x)					\
+	std::remove_cv<std::remove_reference<decltype(x)>::type>::type
 #else
-#define caa_c_transparent_union
+#define caa_scalar_type_to_expr(type)					\
+	unsigned type: (unsigned type)0,				\
+	signed type: (signed type)0
+
+/*
+ * Use C11 _Generic to express unqualified type from expression. This removes
+ * volatile qualifier from expression type.
+ */
+#define caa_unqual_scalar_typeof(x)					\
+	__typeof__(							\
+		_Generic((x),						\
+			char: (char)0,					\
+			caa_scalar_type_to_expr(char),			\
+			caa_scalar_type_to_expr(short),		\
+			caa_scalar_type_to_expr(int),			\
+			caa_scalar_type_to_expr(long),			\
+			caa_scalar_type_to_expr(long long),		\
+			default: (x)					\
+		)							\
+	)
+#endif
+
+/*
+ * Allow user to manually define CMM_SANITIZE_THREAD if their toolchain is not
+ * supported by this check.
+ */
+#ifndef CMM_SANITIZE_THREAD
+# if defined(__GNUC__) && defined(__SANITIZE_THREAD__)
+#  define CMM_SANITIZE_THREAD
+# elif defined(__clang__) && defined(__has_feature)
+#  if __has_feature(thread_sanitizer)
+#   define CMM_SANITIZE_THREAD
+#  endif
+# endif
+#endif	/* !CMM_SANITIZE_THREAD */
+
+/*
+ * Helper to add the volatile qualifier to a pointer.
+ */
+#if defined __cplusplus
+template <typename T>
+volatile T cmm_cast_volatile(T t)
+{
+    return static_cast<volatile T>(t);
+}
+#else
+#  define cmm_cast_volatile(ptr)			\
+	__extension__					\
+	({						\
+		(volatile __typeof__(ptr))(ptr);	\
+	})
 #endif
 
 #endif /* _URCU_COMPILER_H */