assert(!str); \
__builtin_unreachable(); \
} while (0)
-#elif _MSC_VER >= 1200
+#elif defined (_MSC_VER)
#define unreachable(str) \
do { \
assert(!str); \
__assume(0); \
} while (0)
-#endif
-
-#ifndef unreachable
+#else
#define unreachable(str) assert(!str)
#endif
#define assume(expr) ((expr) ? ((void) 0) \
: (assert(!"assumption failed"), \
__builtin_unreachable()))
-#elif _MSC_VER >= 1200
+#elif defined (_MSC_VER)
#define assume(expr) __assume(expr)
#else
#define assume(expr) assert(expr)
#endif
+/* Attribute const is used for functions that have no effects other than their
+ * return value, and only rely on the argument values to compute the return
+ * value. As a result, calls to it can be CSEed. Note that using memory
+ * pointed to by the arguments is not allowed for const functions.
+ */
+#ifdef HAVE_FUNC_ATTRIBUTE_CONST
+#define ATTRIBUTE_CONST __attribute__((__const__))
+#else
+#define ATTRIBUTE_CONST
+#endif
+
#ifdef HAVE_FUNC_ATTRIBUTE_FLATTEN
#define FLATTEN __attribute__((__flatten__))
#else
#define PACKED
#endif
+/* Attribute pure is used for functions that have no effects other than their
+ * return value. As a result, calls to it can be dead code eliminated.
+ */
+#ifdef HAVE_FUNC_ATTRIBUTE_PURE
+#define ATTRIBUTE_PURE __attribute__((__pure__))
+#else
+#define ATTRIBUTE_PURE
+#endif
+
#ifdef __cplusplus
/**
* Macro function that evaluates to true if T is a trivially
# endif
#endif
+#ifdef HAVE_FUNC_ATTRIBUTE_UNUSED
+#define UNUSED __attribute__((unused))
+#else
+#define UNUSED
+#endif
+
+#ifdef HAVE_FUNC_ATTRIBUTE_WARN_UNUSED_RESULT
+#define MUST_CHECK __attribute__((warn_unused_result))
+#else
+#define MUST_CHECK
+#endif
+
+/** Compute ceiling of integer quotient of A divided by B. */
+#define DIV_ROUND_UP( A, B ) ( (A) % (B) == 0 ? (A)/(B) : (A)/(B)+1 )
#endif /* UTIL_MACROS_H */