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- /* Taken from generic/memmove.c; trivially modified to work with
- arch-specific memcopy.h for Cris.
- Copy memory to memory until the specified number of bytes
- has been copied. Overlap is handled correctly.
- Copyright (C) 1991, 1995, 1996, 1997, 2003 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, see
- <http://www.gnu.org/licenses/>. */
- #include <string.h>
- #include "memcopy.h"
- #include "../generic/pagecopy.h"
- void *memmove (void *dest, const void *src, size_t len)
- {
- unsigned long int dstp = (long int) dest;
- unsigned long int srcp = (long int) src;
- /* This test makes the forward copying code be used whenever possible.
- Reduces the working set. */
- if (dstp - srcp >= len) /* *Unsigned* compare! */
- {
- #if 1
- #warning REMINDER: Cris arch-opt memmove assumes memcpy does forward copying!
- memcpy(dest, src, len);
- #else
- /* Copy from the beginning to the end. */
- /* If there not too few bytes to copy, use word copy. */
- if (len >= OP_T_THRES)
- {
- /* Copy just a few bytes to make DSTP aligned. */
- len -= (-dstp) % OPSIZ;
- BYTE_COPY_FWD (dstp, srcp, (-dstp) % OPSIZ);
- /* Copy whole pages from SRCP to DSTP by virtual address
- manipulation, as much as possible. */
- PAGE_COPY_FWD_MAYBE (dstp, srcp, len, len);
- /* Copy from SRCP to DSTP taking advantage of the known
- alignment of DSTP. Number of bytes remaining is put
- in the third argument, i.e. in LEN. This number may
- vary from machine to machine. */
- WORD_COPY_FWD (dstp, srcp, len, len);
- /* Fall out and copy the tail. */
- }
- /* There are just a few bytes to copy. Use byte memory operations. */
- BYTE_COPY_FWD (dstp, srcp, len);
- #endif
- }
- else
- {
- /* Copy from the end to the beginning. */
- srcp += len;
- dstp += len;
- /* If there not too few bytes to copy, use word copy. */
- if (len >= OP_T_THRES)
- {
- /* Copy just a few bytes to make DSTP aligned. */
- len -= dstp % OPSIZ;
- BYTE_COPY_BWD (dstp, srcp, dstp % OPSIZ);
- /* Copy from SRCP to DSTP taking advantage of the known
- alignment of DSTP. Number of bytes remaining is put
- in the third argument, i.e. in LEN. This number may
- vary from machine to machine. */
- WORD_COPY_BWD (dstp, srcp, len, len);
- /* Fall out and copy the tail. */
- }
- /* There are just a few bytes to copy. Use byte memory operations. */
- BYTE_COPY_BWD (dstp, srcp, len);
- }
- return (dest);
- }
- libc_hidden_def(memmove)
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