1 /* 2 * Copyright 2014 Intel Corporation 3 * 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: 10 * 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 13 * Software. 14 * 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 21 * IN THE SOFTWARE. 22 */ 23 24 #ifndef UTIL_MACROS_H 25 #define UTIL_MACROS_H 26 27 #include <assert.h> 28 29 #include "c99_compat.h" 30 31 /* Compute the size of an array */ 32 #ifndef ARRAY_SIZE 33 # define ARRAY_SIZE(x) (sizeof(x) / sizeof(*(x))) 34 #endif 35 36 /* For compatibility with Clang's __has_builtin() */ 37 #ifndef __has_builtin 38 # define __has_builtin(x) 0 39 #endif 40 41 /** 42 * __builtin_expect macros 43 */ 44 #if !defined(HAVE___BUILTIN_EXPECT) 45 # define __builtin_expect(x, y) (x) 46 #endif 47 48 #ifndef likely 49 # ifdef HAVE___BUILTIN_EXPECT 50 # define likely(x) __builtin_expect(!!(x), 1) 51 # define unlikely(x) __builtin_expect(!!(x), 0) 52 # else 53 # define likely(x) (x) 54 # define unlikely(x) (x) 55 # endif 56 #endif 57 58 59 /** 60 * Static (compile-time) assertion. 61 * Basically, use COND to dimension an array. If COND is false/zero the 62 * array size will be -1 and we'll get a compilation error. 63 */ 64 #define STATIC_ASSERT(COND) \ 65 do { \ 66 (void) sizeof(char [1 - 2*!(COND)]); \ 67 } while (0) 68 69 70 /** 71 * Unreachable macro. Useful for suppressing "control reaches end of non-void 72 * function" warnings. 73 */ 74 #ifdef HAVE___BUILTIN_UNREACHABLE 75 #define unreachable(str) \ 76 do { \ 77 assert(!str); \ 78 __builtin_unreachable(); \ 79 } while (0) 80 #elif defined (_MSC_VER) 81 #define unreachable(str) \ 82 do { \ 83 assert(!str); \ 84 __assume(0); \ 85 } while (0) 86 #else 87 #define unreachable(str) assert(!str) 88 #endif 89 90 /** 91 * Assume macro. Useful for expressing our assumptions to the compiler, 92 * typically for purposes of silencing warnings. 93 */ 94 #if __has_builtin(__builtin_assume) 95 #define assume(expr) \ 96 do { \ 97 assert(expr); \ 98 __builtin_assume(expr); \ 99 } while (0) 100 #elif defined HAVE___BUILTIN_UNREACHABLE 101 #define assume(expr) ((expr) ? ((void) 0) \ 102 : (assert(!"assumption failed"), \ 103 __builtin_unreachable())) 104 #elif defined (_MSC_VER) 105 #define assume(expr) __assume(expr) 106 #else 107 #define assume(expr) assert(expr) 108 #endif 109 110 /* Attribute const is used for functions that have no effects other than their 111 * return value, and only rely on the argument values to compute the return 112 * value. As a result, calls to it can be CSEed. Note that using memory 113 * pointed to by the arguments is not allowed for const functions. 114 */ 115 #ifdef HAVE_FUNC_ATTRIBUTE_CONST 116 #define ATTRIBUTE_CONST __attribute__((__const__)) 117 #else 118 #define ATTRIBUTE_CONST 119 #endif 120 121 #ifdef HAVE_FUNC_ATTRIBUTE_FLATTEN 122 #define FLATTEN __attribute__((__flatten__)) 123 #else 124 #define FLATTEN 125 #endif 126 127 #ifdef HAVE_FUNC_ATTRIBUTE_FORMAT 128 #define PRINTFLIKE(f, a) __attribute__ ((format(__printf__, f, a))) 129 #else 130 #define PRINTFLIKE(f, a) 131 #endif 132 133 #ifdef HAVE_FUNC_ATTRIBUTE_MALLOC 134 #define MALLOCLIKE __attribute__((__malloc__)) 135 #else 136 #define MALLOCLIKE 137 #endif 138 139 /* Used to optionally mark structures with misaligned elements or size as 140 * packed, to trade off performance for space. 141 */ 142 #ifdef HAVE_FUNC_ATTRIBUTE_PACKED 143 #define PACKED __attribute__((__packed__)) 144 #else 145 #define PACKED 146 #endif 147 148 /* Attribute pure is used for functions that have no effects other than their 149 * return value. As a result, calls to it can be dead code eliminated. 150 */ 151 #ifdef HAVE_FUNC_ATTRIBUTE_PURE 152 #define ATTRIBUTE_PURE __attribute__((__pure__)) 153 #else 154 #define ATTRIBUTE_PURE 155 #endif 156 157 #ifdef HAVE_FUNC_ATTRIBUTE_RETURNS_NONNULL 158 #define ATTRIBUTE_RETURNS_NONNULL __attribute__((__returns_nonnull__)) 159 #else 160 #define ATTRIBUTE_RETURNS_NONNULL 161 #endif 162 163 #ifdef __cplusplus 164 /** 165 * Macro function that evaluates to true if T is a trivially 166 * destructible type -- that is, if its (non-virtual) destructor 167 * performs no action and all member variables and base classes are 168 * trivially destructible themselves. 169 */ 170 # if (defined(__clang__) && defined(__has_feature)) 171 # if __has_feature(has_trivial_destructor) 172 # define HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T) 173 # endif 174 # elif defined(__GNUC__) 175 # if ((__GNUC__ > 4) || ((__GNUC__ == 4) && (__GNUC_MINOR__ >= 3))) 176 # define HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T) 177 # endif 178 # elif defined(_MSC_VER) && !defined(__INTEL_COMPILER) 179 # if _MSC_VER >= 1800 180 # define HAS_TRIVIAL_DESTRUCTOR(T) __has_trivial_destructor(T) 181 # endif 182 # endif 183 # ifndef HAS_TRIVIAL_DESTRUCTOR 184 /* It's always safe (if inefficient) to assume that a 185 * destructor is non-trivial. 186 */ 187 # define HAS_TRIVIAL_DESTRUCTOR(T) (false) 188 # endif 189 #endif 190 191 /** 192 * PUBLIC/USED macros 193 * 194 * If we build the library with gcc's -fvisibility=hidden flag, we'll 195 * use the PUBLIC macro to mark functions that are to be exported. 196 * 197 * We also need to define a USED attribute, so the optimizer doesn't 198 * inline a static function that we later use in an alias. - ajax 199 */ 200 #ifndef PUBLIC 201 # if defined(__GNUC__) 202 # define PUBLIC __attribute__((visibility("default"))) 203 # define USED __attribute__((used)) 204 # elif defined(_MSC_VER) 205 # define PUBLIC __declspec(dllexport) 206 # define USED 207 # else 208 # define PUBLIC 209 # define USED 210 # endif 211 #endif 212 213 #ifdef HAVE_FUNC_ATTRIBUTE_UNUSED 214 #define UNUSED __attribute__((unused)) 215 #else 216 #define UNUSED 217 #endif 218 219 #define MAYBE_UNUSED UNUSED 220 221 #ifdef HAVE_FUNC_ATTRIBUTE_WARN_UNUSED_RESULT 222 #define MUST_CHECK __attribute__((warn_unused_result)) 223 #else 224 #define MUST_CHECK 225 #endif 226 227 #if defined(__GNUC__) 228 #define ATTRIBUTE_NOINLINE __attribute__((noinline)) 229 #else 230 #define ATTRIBUTE_NOINLINE 231 #endif 232 233 /** Compute ceiling of integer quotient of A divided by B. */ 234 #define DIV_ROUND_UP( A, B ) ( (A) % (B) == 0 ? (A)/(B) : (A)/(B)+1 ) 235 236 /** Clamp X to [MIN,MAX] */ 237 #define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) ) 238 239 /** Minimum of two values: */ 240 #define MIN2( A, B ) ( (A)<(B) ? (A) : (B) ) 241 242 /** Maximum of two values: */ 243 #define MAX2( A, B ) ( (A)>(B) ? (A) : (B) ) 244 245 /** Minimum and maximum of three values: */ 246 #define MIN3( A, B, C ) ((A) < (B) ? MIN2(A, C) : MIN2(B, C)) 247 #define MAX3( A, B, C ) ((A) > (B) ? MAX2(A, C) : MAX2(B, C)) 248 249 #endif /* UTIL_MACROS_H */ 250
