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/*
* Copyright (C) 1995 Advanced RISC Machines Limited. All rights reserved.
*
* This software may be freely used, copied, modified, and distributed
* provided that the above copyright notice is preserved in all copies of the
* software.
*/
/*
* bytesex.c - Code to support byte-sex independence
* Copyright: (C) 1991, Advanced RISC Machines Ltd., Cambridge, England.
*/
/*
* RCS $Revision$
* Checkin $Date$
*/
#include "bytesex.h"
static int reversing_bytes = 0;
void bytesex_reverse(yes_or_no)
int yes_or_no;
{ reversing_bytes = yes_or_no;
}
int bytesex_reversing()
{
return reversing_bytes;
}
int32 bytesex_hostval(v)
int32 v;
{ /* Return v with the same endian-ness as the host */
/* This mess generates better ARM code than the more obvious mess */
/* and may eventually peephole to optimal code... */
if (reversing_bytes)
{ unsigned32 t;
/* t = v ^ (v ror 16) */
t = v ^ ((v << 16) | (((unsigned32)v) >> 16));
t &= ~0xff0000;
/* v = v ror 8 */
v = (v << 24) | (((unsigned32)v) >> 8);
v = v ^ (t >> 8);
}
return v;
}
int32 bytesex_hostval_16(v)
int32 v;
{
if (reversing_bytes) {
v = ((v >> 8) & 0xff) | ((v << 8) & 0xff00);
}
return v;
}
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