+/**
+ * PUBLIC/USED macros
+ *
+ * If we build the library with gcc's -fvisibility=hidden flag, we'll
+ * use the PUBLIC macro to mark functions that are to be exported.
+ *
+ * We also need to define a USED attribute, so the optimizer doesn't
+ * inline a static function that we later use in an alias. - ajax
+ */
+#ifndef PUBLIC
+# if defined(__GNUC__)
+# define PUBLIC __attribute__((visibility("default")))
+# define USED __attribute__((used))
+# elif defined(_MSC_VER)
+# define PUBLIC __declspec(dllexport)
+# define USED
+# else
+# define PUBLIC
+# define USED
+# endif
+#endif
+
+#ifdef HAVE_FUNC_ATTRIBUTE_UNUSED
+#define UNUSED __attribute__((unused))
+#else
+#define UNUSED
+#endif
+
+#define MAYBE_UNUSED UNUSED
+
+#ifdef HAVE_FUNC_ATTRIBUTE_WARN_UNUSED_RESULT
+#define MUST_CHECK __attribute__((warn_unused_result))
+#else
+#define MUST_CHECK
+#endif
+
+#if defined(__GNUC__)
+#define ATTRIBUTE_NOINLINE __attribute__((noinline))
+#else
+#define ATTRIBUTE_NOINLINE
+#endif
+
+
+/**
+ * Check that STRUCT::FIELD can hold MAXVAL. We use a lot of bitfields
+ * in Mesa/gallium. We have to be sure they're of sufficient size to
+ * hold the largest expected value.
+ * Note that with MSVC, enums are signed and enum bitfields need one extra
+ * high bit (always zero) to ensure the max value is handled correctly.
+ * This macro will detect that with MSVC, but not GCC.
+ */
+#define ASSERT_BITFIELD_SIZE(STRUCT, FIELD, MAXVAL) \
+ do { \
+ MAYBE_UNUSED STRUCT s; \
+ s.FIELD = (MAXVAL); \
+ assert((int) s.FIELD == (MAXVAL) && "Insufficient bitfield size!"); \
+ } while (0)
+
+
+/** Compute ceiling of integer quotient of A divided by B. */
+#define DIV_ROUND_UP( A, B ) ( (A) % (B) == 0 ? (A)/(B) : (A)/(B)+1 )
+
+/** Clamp X to [MIN,MAX]. Turn NaN into MIN, arbitrarily. */
+#define CLAMP( X, MIN, MAX ) ( (X)>(MIN) ? ((X)>(MAX) ? (MAX) : (X)) : (MIN) )
+
+/** Minimum of two values: */
+#define MIN2( A, B ) ( (A)<(B) ? (A) : (B) )
+
+/** Maximum of two values: */
+#define MAX2( A, B ) ( (A)>(B) ? (A) : (B) )
+
+/** Minimum and maximum of three values: */
+#define MIN3( A, B, C ) ((A) < (B) ? MIN2(A, C) : MIN2(B, C))
+#define MAX3( A, B, C ) ((A) > (B) ? MAX2(A, C) : MAX2(B, C))
+
+/** Align a value to a power of two */
+#define ALIGN_POT(x, pot_align) (((x) + (pot_align) - 1) & ~((pot_align) - 1))
+
+/**
+ * Macro for declaring an explicit conversion operator. Defaults to an
+ * implicit conversion if C++11 is not supported.
+ */
+#if __cplusplus >= 201103L
+#define EXPLICIT_CONVERSION explicit
+#elif defined(__cplusplus)
+#define EXPLICIT_CONVERSION
+#endif
+