Memory Alignment

Fast, bitwise macros for aligning pointers and sizes to powers of 2. More...

Macros
#define	ALIGN_UP_POW2(x, p)
	Aligns a value UP to the nearest power of 2.
#define	ALIGN_DOWN_POW2(x, p)
	Aligns a value DOWN to the nearest power of 2.
#define	IS_POW2_OR_ZERO(x)
	Checks if a given integer is a power of 2 (or zero).

Detailed Description

Fast, bitwise macros for aligning pointers and sizes to powers of 2.

Macro Definition Documentation

ALIGN_DOWN_POW2

#define ALIGN_DOWN_POW2	(		x,
			p )

Value:

((x) & ~((p) - 1))

Aligns a value DOWN to the nearest power of 2.

Parameters

x	The value to align.
p	The alignment boundary (must be a power of 2).

Returns

The aligned value.

Definition at line 340 of file base_macros.h.

ALIGN_UP_POW2

#define ALIGN_UP_POW2	(		x,
			p )

Value:

(((x) + (p) - 1) & ~((p) - 1))

Aligns a value UP to the nearest power of 2.

Parameters

x	The value to align.
p	The alignment boundary (must be a power of 2).

Returns

The aligned value.

Definition at line 332 of file base_macros.h.

IS_POW2_OR_ZERO

#define IS_POW2_OR_ZERO

(

x

)

Value:

(((x) & ((x) - 1)) == 0)

Checks if a given integer is a power of 2 (or zero).

Parameters

x	The value to check.

Returns

1 (true) if it is a power of 2, 0 (false) otherwise.

Definition at line 347 of file base_macros.h.