projects / babeltrace.git / blame
| Commit | Line | Data |
|---|---|---|
| de0ba614 | 1 | /* |
| 0235b0db | 2 | * SPDX-License-Identifier: MIT |
| de0ba614 | 3 | * |
| 0235b0db | 4 | * Copyright 2010 Mathieu Desnoyers <mathieu.desnoyers@efficios.com> |
| de0ba614 MD |
5 | */ |
| 6 | ||
| 0235b0db MJ |
7 | #ifndef _BABELTRACE_ALIGN_H |
| 8 | #define _BABELTRACE_ALIGN_H | |
| 9 | ||
| 578e048b MJ |
10 | #include "compat/compiler.h" |
| 11 | #include "compat/limits.h" | |
| c4f467da | 12 | |
| 6dc2ca62 MD |
13 | #define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a) - 1) |
| 14 | #define __ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask)) | |
| 15 | #define PTR_ALIGN(p, a) ((typeof(p)) ALIGN((unsigned long) (p), a)) | |
| 16 | #define ALIGN_FLOOR(x, a) __ALIGN_FLOOR_MASK(x, (typeof(x)) (a) - 1) | |
| 17 | #define __ALIGN_FLOOR_MASK(x, mask) ((x) & ~(mask)) | |
| 18 | #define PTR_ALIGN_FLOOR(p, a) \ | |
| 19 | ((typeof(p)) ALIGN_FLOOR((unsigned long) (p), a)) | |
| 20 | #define IS_ALIGNED(x, a) (((x) & ((typeof(x)) (a) - 1)) == 0) | |
| 21 | ||
| 22 | /* | |
| 23 | * Align pointer on natural object alignment. | |
| 24 | */ | |
| 25 | #define object_align(obj) PTR_ALIGN(obj, __alignof__(*(obj))) | |
| 26 | #define object_align_floor(obj) PTR_ALIGN_FLOOR(obj, __alignof__(*(obj))) | |
| 27 | ||
| 28 | /** | |
| 29 | * offset_align - Calculate the offset needed to align an object on its natural | |
| 30 | * alignment towards higher addresses. | |
| 31 | * @align_drift: object offset from an "alignment"-aligned address. | |
| 32 | * @alignment: natural object alignment. Must be non-zero, power of 2. | |
| 33 | * | |
| 34 | * Returns the offset that must be added to align towards higher | |
| 35 | * addresses. | |
| 36 | */ | |
| 37 | #define offset_align(align_drift, alignment) \ | |
| 38 | ({ \ | |
| 39 | MAYBE_BUILD_BUG_ON((alignment) == 0 \ | |
| 40 | || ((alignment) & ((alignment) - 1))); \ | |
| 41 | (((alignment) - (align_drift)) & ((alignment) - 1)); \ | |
| 42 | }) | |
| 43 | ||
| 44 | /** | |
| 45 | * offset_align_floor - Calculate the offset needed to align an object | |
| 46 | * on its natural alignment towards lower addresses. | |
| 47 | * @align_drift: object offset from an "alignment"-aligned address. | |
| 48 | * @alignment: natural object alignment. Must be non-zero, power of 2. | |
| 49 | * | |
| 50 | * Returns the offset that must be substracted to align towards lower addresses. | |
| 51 | */ | |
| 52 | #define offset_align_floor(align_drift, alignment) \ | |
| 53 | ({ \ | |
| 54 | MAYBE_BUILD_BUG_ON((alignment) == 0 \ | |
| 55 | || ((alignment) & ((alignment) - 1))); \ | |
| a12af8c1 | 56 | (((align_drift) - (alignment)) & ((alignment) - 1)); \ |
| 6dc2ca62 MD |
57 | }) |
| 58 | ||
| d79865b9 | 59 | #endif /* _BABELTRACE_ALIGN_H */ |