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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.

 */

/*

 * angel_bytesex.c - Code to support byte-sex independence

 * Copyright: (C) 1991, Advanced RISC Machines Ltd., Cambridge, England.

 */

/*

 * RCS $Revision: 1.1.1.1 $

 * Checkin $Date: 2001-05-18 11:16:30 $

 */

#include "angel_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;

}