1 /* Copyright 2013 The ChromiumOS Authors 2 * Use of this source code is governed by a BSD-style license that can be 3 * found in the LICENSE file. 4 */ 5 6 /* Handy clever tricks */ 7 8 #ifndef __CROS_EC_COMPILE_TIME_MACROS_H 9 #define __CROS_EC_COMPILE_TIME_MACROS_H 10 11 /* Test an important condition at compile time, not run time */ 12 #define _BA1_(cond, line) \ 13 extern int __build_assertion_##line[1 - 2 * !(cond)] \ 14 __attribute__((unused)) 15 #define _BA0_(c, x) _BA1_(c, x) 16 #define BUILD_ASSERT(cond) _BA0_(cond, __LINE__) 17 18 /* 19 * Test an important condition inside code path at run time, taking advantage of 20 * -Werror=div-by-zero. 21 */ 22 #define BUILD_CHECK_INLINE(value, cond_true) ((value) / (!!(cond_true))) 23 24 /* Number of elements in an array */ 25 #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0])) 26 27 /* Make for loops that iterate over pointers to array entries more readable */ 28 #define ARRAY_BEGIN(array) (array) 29 #define ARRAY_END(array) ((array) + ARRAY_SIZE(array)) 30 31 /* Just in case - http://gcc.gnu.org/onlinedocs/gcc/Offsetof.html */ 32 #ifndef offsetof 33 #define offsetof(type, member) __builtin_offsetof(type, member) 34 #endif 35 36 #define member_size(type, member) sizeof(((type *)0)->member) 37 38 /* 39 * Bit operation macros. 40 */ 41 #define BIT(nr) (1U << (nr)) 42 #define BIT_ULL(nr) (1ULL << (nr)) 43 44 #endif /* __CROS_EC_COMPILE_TIME_MACROS_H */ 45