X-Git-Url: https://git.liburcu.org/?a=blobdiff_plain;f=include%2Furcu%2Fcompiler.h;h=197656c617d786f8af88f5648a60483ac224f3c4;hb=455a8429f01ee5f98161bd8710c50ba0bdec61f2;hp=5b994076f47c913b28d636ae6e7262261befe103;hpb=d3d3857f678627e7bbfb5a8d6f3bc15cd2a694d9;p=urcu.git

diff --git a/include/urcu/compiler.h b/include/urcu/compiler.h
index 5b99407..197656c 100644
--- a/include/urcu/compiler.h
+++ b/include/urcu/compiler.h
@@ -15,10 +15,16 @@
 # 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
@@ -130,4 +136,93 @@
 				+ __GNUC_PATCHLEVEL__)
 #endif
 
+#ifdef __cplusplus
+#define caa_unqual_scalar_typeof(x)					\
+	std::remove_cv<std::remove_reference<decltype(x)>::type>::type
+#else
+#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
+
+/*
+ * Compile time assertion.
+ * - predicate: boolean expression to evaluate,
+ * - msg: string to print to the user on failure when `static_assert()` is
+ *   supported,
+ * - c_identifier_msg: message to be included in the typedef to emulate a
+ *   static assertion. This parameter must be a valid C identifier as it will
+ *   be used as a typedef name.
+ */
+#ifdef __cplusplus
+#define urcu_static_assert(predicate, msg, c_identifier_msg)  \
+	static_assert(predicate, msg)
+#elif defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 201112L)
+#define urcu_static_assert(predicate, msg, c_identifier_msg)  \
+	_Static_assert(predicate, msg)
+#else
+/*
+ * Evaluates the predicate and emit a compilation error on failure.
+ *
+ * If the predicate evaluates to true, this macro emits a function
+ * prototype with an argument type which is an array of size 0.
+ *
+ * If the predicate evaluates to false, this macro emits a function
+ * prototype with an argument type which is an array of negative size
+ * which is invalid in C and forces a compiler error. The
+ * c_identifier_msg parameter is used as the argument identifier so it
+ * is printed to the user when the error is reported.
+ */
+#define urcu_static_assert(predicate, msg, c_identifier_msg)  \
+	void urcu_static_assert_proto(char c_identifier_msg[2*!!(predicate)-1])
+#endif
+
 #endif /* _URCU_COMPILER_H */