2 * Copyright © 2014 Intel Corporation
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
27 /* Compute the size of an array */
29 # define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x)))
32 /* For compatibility with Clang's __has_builtin() */
34 # define __has_builtin(x) 0
38 * __builtin_expect macros
40 #if !defined(HAVE___BUILTIN_EXPECT)
41 # define __builtin_expect(x, y) (x)
45 # ifdef HAVE___BUILTIN_EXPECT
46 # define likely(x) __builtin_expect(!!(x), 1)
47 # define unlikely(x) __builtin_expect(!!(x), 0)
49 # define likely(x) (x)
50 # define unlikely(x) (x)
56 * Static (compile-time) assertion.
57 * Basically, use COND to dimension an array. If COND is false/zero the
58 * array size will be -1 and we'll get a compilation error.
60 #define STATIC_ASSERT(COND) \
62 (void) sizeof(char [1 - 2*!(COND)]); \
67 * Unreachable macro. Useful for suppressing "control reaches end of non-void
70 #ifdef HAVE___BUILTIN_UNREACHABLE
71 #define unreachable(str) \
74 __builtin_unreachable(); \
76 #elif defined (_MSC_VER)
77 #define unreachable(str) \
83 #define unreachable(str) assert(!str)
87 * Assume macro. Useful for expressing our assumptions to the compiler,
88 * typically for purposes of silencing warnings.
90 #if __has_builtin(__builtin_assume)
91 #define assume(expr) \
94 __builtin_assume(expr); \
96 #elif defined HAVE___BUILTIN_UNREACHABLE
97 #define assume(expr) ((expr) ? ((void) 0) \
98 : (assert(!"assumption failed"), \
99 __builtin_unreachable()))
100 #elif defined (_MSC_VER)
101 #define assume(expr) __assume(expr)
103 #define assume(expr) assert(expr)
106 #ifdef HAVE_FUNC_ATTRIBUTE_FLATTEN
107 #define FLATTEN __attribute__((__flatten__))
112 #ifdef HAVE_FUNC_ATTRIBUTE_FORMAT
113 #define PRINTFLIKE(f, a) __attribute__ ((format(__printf__, f, a)))
115 #define PRINTFLIKE(f, a)
118 #ifdef HAVE_FUNC_ATTRIBUTE_MALLOC
119 #define MALLOCLIKE __attribute__((__malloc__))
124 /* Used to optionally mark structures with misaligned elements or size as
125 * packed, to trade off performance for space.
127 #ifdef HAVE_FUNC_ATTRIBUTE_PACKED
128 #define PACKED __attribute__((__packed__))
135 * Macro function that evaluates to true if T is a trivially
136 * destructible type -- that is, if its (non-virtual) destructor
137 * performs no action and all member variables and base classes are
138 * trivially destructible themselves.
140 # if defined(__GNUC__)
141 # if ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3)))
142 # define HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T)
144 # elif (defined(__clang__) && defined(__has_feature))
145 # if __has_feature(has_trivial_destructor)
146 # define HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T)
149 # ifndef HAS_TRIVIAL_DESTRUCTOR
150 /* It's always safe (if inefficient) to assume that a
151 * destructor is non-trivial.
153 # define HAS_TRIVIAL_DESTRUCTOR(T) (false)
160 * If we build the library with gcc's -fvisibility=hidden flag, we'll
161 * use the PUBLIC macro to mark functions that are to be exported.
163 * We also need to define a USED attribute, so the optimizer doesn't
164 * inline a static function that we later use in an alias. - ajax
167 # if defined(__GNUC__) || (defined(__SUNPRO_C) && (__SUNPRO_C >= 0x590))
168 # define PUBLIC __attribute__((visibility("default")))
169 # define USED __attribute__((used))
170 # elif defined(_MSC_VER)
171 # define PUBLIC __declspec(dllexport)
179 #ifdef HAVE_FUNC_ATTRIBUTE_UNUSED
180 #define UNUSED __attribute__((unused))
185 /** Compute ceiling of integer quotient of A divided by B. */
186 #define DIV_ROUND_UP( A, B ) ( (A) % (B) == 0 ? (A)/(B) : (A)/(B)+1 )
188 #endif /* UTIL_MACROS_H */