[babeltrace.git] / include / ctf / align.h

#ifndef _CTF_ALIGN_H
#define _CTF_ALIGN_H

#include <ctf/compiler.h>

#define ALIGN(x, a)		__ALIGN_MASK(x, (typeof(x))(a) - 1)
#define __ALIGN_MASK(x, mask)	(((x) + (mask)) & ~(mask))
#define PTR_ALIGN(p, a)		((typeof(p)) ALIGN((unsigned long) (p), a))
#define ALIGN_FLOOR(x, a)	__ALIGN_FLOOR_MASK(x, (typeof(x)) (a) - 1)
#define __ALIGN_FLOOR_MASK(x, mask)	((x) & ~(mask))
#define PTR_ALIGN_FLOOR(p, a) \
			((typeof(p)) ALIGN_FLOOR((unsigned long) (p), a))
#define IS_ALIGNED(x, a)	(((x) & ((typeof(x)) (a) - 1)) == 0)

/*
 * Align pointer on natural object alignment.
 */
#define object_align(obj)	PTR_ALIGN(obj, __alignof__(*(obj)))
#define object_align_floor(obj)	PTR_ALIGN_FLOOR(obj, __alignof__(*(obj)))

/**
 * offset_align - Calculate the offset needed to align an object on its natural
 *                alignment towards higher addresses.
 * @align_drift:  object offset from an "alignment"-aligned address.
 * @alignment:    natural object alignment. Must be non-zero, power of 2.
 *
 * Returns the offset that must be added to align towards higher
 * addresses.
 */
#define offset_align(align_drift, alignment)				       \
	({								       \
		MAYBE_BUILD_BUG_ON((alignment) == 0			       \
				   || ((alignment) & ((alignment) - 1)));      \
		(((alignment) - (align_drift)) & ((alignment) - 1));	       \
	})

/**
 * offset_align_floor - Calculate the offset needed to align an object
 *                      on its natural alignment towards lower addresses.
 * @align_drift:  object offset from an "alignment"-aligned address.
 * @alignment:    natural object alignment. Must be non-zero, power of 2.
 *
 * Returns the offset that must be substracted to align towards lower addresses.
 */
#define offset_align_floor(align_drift, alignment)			       \
	({								       \
		MAYBE_BUILD_BUG_ON((alignment) == 0			       \
				   || ((alignment) & ((alignment) - 1)));      \
		(((align_drift) - (alignment)) & ((alignment) - 1);	       \
	})

#endif /* _CTF_ALIGN_H */
Commit	Line	Data
	1	#ifndef _CTF_ALIGN_H
	2	#define _CTF_ALIGN_H
	3
	4	#include <ctf/compiler.h>
	5
	6	#define ALIGN(x, a) __ALIGN_MASK(x, (typeof(x))(a) - 1)
	7	#define __ALIGN_MASK(x, mask) (((x) + (mask)) & ~(mask))
	8	#define PTR_ALIGN(p, a) ((typeof(p)) ALIGN((unsigned long) (p), a))
	9	#define ALIGN_FLOOR(x, a) __ALIGN_FLOOR_MASK(x, (typeof(x)) (a) - 1)
	10	#define __ALIGN_FLOOR_MASK(x, mask) ((x) & ~(mask))
	11	#define PTR_ALIGN_FLOOR(p, a) \
	12	((typeof(p)) ALIGN_FLOOR((unsigned long) (p), a))
	13	#define IS_ALIGNED(x, a) (((x) & ((typeof(x)) (a) - 1)) == 0)
	14
	15	/*
	16	* Align pointer on natural object alignment.
	17	*/
	18	#define object_align(obj) PTR_ALIGN(obj, __alignof__(*(obj)))
	19	#define object_align_floor(obj) PTR_ALIGN_FLOOR(obj, __alignof__(*(obj)))
	20
	21	/**
	22	* offset_align - Calculate the offset needed to align an object on its natural
	23	* alignment towards higher addresses.
	24	* @align_drift: object offset from an "alignment"-aligned address.
	25	* @alignment: natural object alignment. Must be non-zero, power of 2.
	26	*
	27	* Returns the offset that must be added to align towards higher
	28	* addresses.
	29	*/
	30	#define offset_align(align_drift, alignment) \
	31	({ \
	32	MAYBE_BUILD_BUG_ON((alignment) == 0 \
	33	\|\| ((alignment) & ((alignment) - 1))); \
	34	(((alignment) - (align_drift)) & ((alignment) - 1)); \
	35	})
	36
	37	/**
	38	* offset_align_floor - Calculate the offset needed to align an object
	39	* on its natural alignment towards lower addresses.
	40	* @align_drift: object offset from an "alignment"-aligned address.
	41	* @alignment: natural object alignment. Must be non-zero, power of 2.
	42	*
	43	* Returns the offset that must be substracted to align towards lower addresses.
	44	*/
	45	#define offset_align_floor(align_drift, alignment) \
	46	({ \
	47	MAYBE_BUILD_BUG_ON((alignment) == 0 \
	48	\|\| ((alignment) & ((alignment) - 1))); \
	49	(((align_drift) - (alignment)) & ((alignment) - 1); \
	50	})
	51
	52	#endif /* _CTF_ALIGN_H */