[thirdparty/glibc.git] / sysdeps / generic / pagecopy.h

/* Macros for copying by pages; used in memcpy, memmove.
   Copyright (C) 1995-2021 Free Software Foundation, Inc.
   This file is part of the GNU C Library.

   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
   <https://www.gnu.org/licenses/>.  */

/* The macro PAGE_COPY_FWD_MAYBE defined in memcopy.h is used in memmove if the
   PAGE_COPY_THRESHOLD macro is set to a non-zero value.  The default is 0,
   that is copying by pages is not implemented.

   System-specific pagecopy.h files that want to support page copying should
   define these macros:

   PAGE_COPY_THRESHOLD
   -- A non-zero minimum size for which virtual copying by pages is worthwhile.

   PAGE_SIZE
   -- Size of a page.

   PAGE_COPY_FWD (dstp, srcp, nbytes_left, nbytes)
   -- Macro to perform the virtual copy operation.
   The pointers will be aligned to PAGE_SIZE bytes.
*/

#define PAGE_COPY_THRESHOLD 0
Commit	Line	Data
99f8dc92	1	/* Macros for copying by pages; used in memcpy, memmove.
2b778ceb	2	Copyright (C) 1995-2021 Free Software Foundation, Inc.
478b92f0 UD	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
41bdb6e2 AJ	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.
478b92f0 UD	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
41bdb6e2	13	Lesser General Public License for more details.
478b92f0	14
41bdb6e2	15	You should have received a copy of the GNU Lesser General Public
59ba27a6	16	License along with the GNU C Library; if not, see
5a82c748	17	<https://www.gnu.org/licenses/>. */
67a87b93	18
99f8dc92 SP	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.
67a87b93	22
99f8dc92 SP	23	System-specific pagecopy.h files that want to support page copying should
99f8dc92 SP	24	define these macros:
67a87b93 RM	25
67a87b93 RM	26	PAGE_COPY_THRESHOLD
99f8dc92	27	-- A non-zero minimum size for which virtual copying by pages is worthwhile.
67a87b93 RM	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
99f8dc92	37	#define PAGE_COPY_THRESHOLD 0