1/* Macros for copying by pages; used in memcpy, memmove.
2 Copyright (C) 1995-2020 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
4
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
9
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
14
15 You should have received a copy of the GNU Lesser General Public
16 License along with the GNU C Library; if not, see
17 <https://www.gnu.org/licenses/>. */
18
19/* The macro PAGE_COPY_FWD_MAYBE defined in memcopy.h is used in memmove if the
20 PAGE_COPY_THRESHOLD macro is set to a non-zero value. The default is 0,
21 that is copying by pages is not implemented.
22
23 System-specific pagecopy.h files that want to support page copying should
24 define these macros:
25
26 PAGE_COPY_THRESHOLD
27 -- A non-zero minimum size for which virtual copying by pages is worthwhile.
28
29 PAGE_SIZE
30 -- Size of a page.
31
32 PAGE_COPY_FWD (dstp, srcp, nbytes_left, nbytes)
33 -- Macro to perform the virtual copy operation.
34 The pointers will be aligned to PAGE_SIZE bytes.
35*/
36
37#define PAGE_COPY_THRESHOLD 0
38