1 /* 2 * Copyright (c) 2016, ARM Limited and Contributors. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are met: 6 * 7 * Redistributions of source code must retain the above copyright notice, this 8 * list of conditions and the following disclaimer. 9 * 10 * Redistributions in binary form must reproduce the above copyright notice, 11 * this list of conditions and the following disclaimer in the documentation 12 * and/or other materials provided with the distribution. 13 * 14 * Neither the name of ARM nor the names of its contributors may be used 15 * to endorse or promote products derived from this software without specific 16 * prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 19 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE 22 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 23 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 24 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 25 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 26 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 27 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 28 * POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 #ifndef __UTILS_H__ 32 #define __UTILS_H__ 33 34 /* Compute the number of elements in the given array */ 35 #define ARRAY_SIZE(a) \ 36 (sizeof(a) / sizeof((a)[0])) 37 38 #define IS_POWER_OF_TWO(x) \ 39 (((x) & ((x) - 1)) == 0) 40 41 #define SIZE_FROM_LOG2_WORDS(n) (4 << (n)) 42 43 /* 44 * The round_up() macro rounds up a value to the given boundary in a 45 * type-agnostic yet type-safe manner. The boundary must be a power of two. 46 * In other words, it computes the smallest multiple of boundary which is 47 * greater than or equal to value. 48 * 49 * round_down() is similar but rounds the value down instead. 50 */ 51 #define round_boundary(value, boundary) \ 52 ((__typeof__(value))((boundary) - 1)) 53 54 #define round_up(value, boundary) \ 55 ((((value) - 1) | round_boundary(value, boundary)) + 1) 56 57 #define round_down(value, boundary) \ 58 ((value) & ~round_boundary(value, boundary)) 59 60 /* 61 * Evaluates to 1 if (ptr + inc) overflows, 0 otherwise. 62 * Both arguments must be unsigned pointer values (i.e. uintptr_t). 63 */ 64 #define check_uptr_overflow(ptr, inc) \ 65 (((ptr) > UINTPTR_MAX - (inc)) ? 1 : 0) 66 67 #endif /* __UTILS_H__ */ 68