| 1 | /* Macros for copying by pages; used in memcpy, memmove. |
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| 2 | Copyright (C) 1995-2022 Free Software Foundation, Inc. |
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| 3 | This file is part of the GNU C Library. |
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| 4 | |
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| 5 | The GNU C Library is free software; you can redistribute it and/or |
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| 6 | modify it under the terms of the GNU Lesser General Public |
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| 7 | License as published by the Free Software Foundation; either |
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| 8 | version 2.1 of the License, or (at your option) any later version. |
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| 9 | |
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| 10 | The GNU C Library is distributed in the hope that it will be useful, |
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| 11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
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| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
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| 13 | Lesser General Public License for more details. |
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| 14 | |
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| 15 | You should have received a copy of the GNU Lesser General Public |
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| 16 | License along with the GNU C Library; if not, see |
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| 17 | <https://www.gnu.org/licenses/>. */ |
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| 18 | |
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| 19 | /* The macro PAGE_COPY_FWD_MAYBE defined in memcopy.h is used in memmove if the |
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| 20 | PAGE_COPY_THRESHOLD macro is set to a non-zero value. The default is 0, |
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| 21 | that is copying by pages is not implemented. |
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| 22 | |
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| 23 | System-specific pagecopy.h files that want to support page copying should |
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| 24 | define these macros: |
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| 25 | |
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| 26 | PAGE_COPY_THRESHOLD |
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| 27 | -- A non-zero minimum size for which virtual copying by pages is worthwhile. |
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| 28 | |
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| 29 | PAGE_SIZE |
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| 30 | -- Size of a page. |
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| 31 | |
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| 32 | PAGE_COPY_FWD (dstp, srcp, nbytes_left, nbytes) |
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| 33 | -- Macro to perform the virtual copy operation. |
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| 34 | The pointers will be aligned to PAGE_SIZE bytes. |
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| 35 | */ |
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| 36 | |
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| 37 | #define PAGE_COPY_THRESHOLD 0 |
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| 38 | |
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