text: /* memcopy.h -- definitions for memory copy functions.  Motorola 68020 version.
     Copyright (C) 1991, 1997 Free Software Foundation, Inc.
     This file is part of the GNU C Library.
     Contributed by Torbjorn Granlund (tege@sics.se).
  
     The GNU C Library is free software; you can redistribute it and/or
     modify it under the terms of the GNU Lesser General Public
     License as published by the Free Software Foundation; either
     version 2.1 of the License, or (at your option) any later version.
  
     The GNU C Library is distributed in the hope that it will be useful,
     but WITHOUT ANY WARRANTY; without even the implied warranty of
     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
     Lesser General Public License for more details.
  
     You should have received a copy of the GNU Lesser General Public
     License along with the GNU C Library; if not, write to the Free
     Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
     02111-1307 USA.  */
  
  #include <sysdeps/generic/memcopy.h>
  
  #if	defined(__mc68020__) || defined(mc68020)
  
  #undef	OP_T_THRES
  #define	OP_T_THRES	16
  
  /* WORD_COPY_FWD and WORD_COPY_BWD are not symmetric on the 68020,
     because of its weird instruction overlap characteristics.  */
  
  #undef	WORD_COPY_FWD
  #define WORD_COPY_FWD(dst_bp, src_bp, nbytes_left, nbytes)		      \
    do									      \
      {									      \
        size_t __nwords = (nbytes) / sizeof (op_t);			      \
        size_t __nblocks = __nwords / 8 + 1;				      \
        dst_bp -= (8 - __nwords % 8) * sizeof (op_t);			      \
        src_bp -= (8 - __nwords % 8) * sizeof (op_t);			      \
        switch (__nwords % 8)						      \
  	do								      \
  	  {								      \
  	    ((op_t *) dst_bp)[0] = ((op_t *) src_bp)[0];		      \
  	  case 7:							      \
  	    ((op_t *) dst_bp)[1] = ((op_t *) src_bp)[1];		      \
  	  case 6:							      \
  	    ((op_t *) dst_bp)[2] = ((op_t *) src_bp)[2];		      \
  	  case 5:							      \
  	    ((op_t *) dst_bp)[3] = ((op_t *) src_bp)[3];		      \
  	  case 4:							      \
  	    ((op_t *) dst_bp)[4] = ((op_t *) src_bp)[4];		      \
  	  case 3:							      \
  	    ((op_t *) dst_bp)[5] = ((op_t *) src_bp)[5];		      \
  	  case 2:							      \
  	    ((op_t *) dst_bp)[6] = ((op_t *) src_bp)[6];		      \
  	  case 1:							      \
  	    ((op_t *) dst_bp)[7] = ((op_t *) src_bp)[7];		      \
  	  case 0:							      \
  	    src_bp += 32;						      \
  	    dst_bp += 32;						      \
  	    __nblocks--;						      \
  	  }								      \
        while (__nblocks != 0);						      \
        (nbytes_left) = (nbytes) % sizeof (op_t);				      \
      } while (0)
  
  #undef	WORD_COPY_BWD
  #define WORD_COPY_BWD(dst_ep, src_ep, nbytes_left, nbytes)		      \
    do									      \
      {									      \
        size_t __nblocks = (nbytes) / 32 + 1;				      \
        switch ((nbytes) / sizeof (op_t) % 8)				      \
  	do								      \
  	  {								      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 7:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 6:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 5:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 4:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 3:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 2:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 1:							      \
  	    *--((op_t *) dst_ep) = *--((op_t *) src_ep);		      \
  	  case 0:							      \
  	    __nblocks--;						      \
  	  }								      \
        while (__nblocks != 0);						      \
        (nbytes_left) = (nbytes) % sizeof (op_t);				      \
      } while (0)
  
  #endif
  