| Current Path : /usr/src/lib/libstand/ |
FreeBSD hs32.drive.ne.jp 9.1-RELEASE FreeBSD 9.1-RELEASE #1: Wed Jan 14 12:18:08 JST 2015 root@hs32.drive.ne.jp:/sys/amd64/compile/hs32 amd64 |
| Current File : //usr/src/lib/libstand/bswap.c |
/*
* Written by Manuel Bouyer <bouyer@netbsd.org>.
* Public domain.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD: release/9.1.0/lib/libstand/bswap.c 237989 2012-07-02 10:00:28Z obrien $");
#if defined(LIBC_SCCS) && !defined(lint)
static char *rcsid = "$NetBSD: bswap32.c,v 1.1 1997/10/09 15:42:33 bouyer Exp $";
static char *rcsid = "$NetBSD: bswap64.c,v 1.3 2009/03/16 05:59:21 cegger Exp $";
#endif
#include <sys/types.h>
#undef bswap32
#undef bswap64
u_int32_t bswap32(u_int32_t x);
u_int64_t bswap64(u_int64_t x);
u_int32_t
bswap32(u_int32_t x)
{
return ((x << 24) & 0xff000000 ) |
((x << 8) & 0x00ff0000 ) |
((x >> 8) & 0x0000ff00 ) |
((x >> 24) & 0x000000ff );
}
u_int64_t
bswap64(u_int64_t x)
{
#ifdef __LP64__
/*
* Assume we have wide enough registers to do it without touching
* memory.
*/
return ( (x << 56) & 0xff00000000000000UL ) |
( (x << 40) & 0x00ff000000000000UL ) |
( (x << 24) & 0x0000ff0000000000UL ) |
( (x << 8) & 0x000000ff00000000UL ) |
( (x >> 8) & 0x00000000ff000000UL ) |
( (x >> 24) & 0x0000000000ff0000UL ) |
( (x >> 40) & 0x000000000000ff00UL ) |
( (x >> 56) & 0x00000000000000ffUL );
#else
/*
* Split the operation in two 32bit steps.
*/
u_int32_t tl, th;
th = bswap32((u_int32_t)(x & 0x00000000ffffffffULL));
tl = bswap32((u_int32_t)((x >> 32) & 0x00000000ffffffffULL));
return ((u_int64_t)th << 32) | tl;
#endif
}