| 1 | /* Swap the content of two memory blocks, overlap is NOT handled. |
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| 2 | Copyright (C) 2023-2024 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 | #include <string.h> |
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| 20 | |
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| 21 | static inline void |
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| 22 | __memswap (void *__restrict p1, void *__restrict p2, size_t n) |
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| 23 | { |
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| 24 | /* Use multiple small memcpys with constant size to enable inlining on most |
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| 25 | targets. */ |
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| 26 | enum { SWAP_GENERIC_SIZE = 32 }; |
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| 27 | unsigned char tmp[SWAP_GENERIC_SIZE]; |
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| 28 | while (n > SWAP_GENERIC_SIZE) |
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| 29 | { |
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| 30 | memcpy (tmp, p1, SWAP_GENERIC_SIZE); |
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| 31 | p1 = __mempcpy (p1, p2, SWAP_GENERIC_SIZE); |
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| 32 | p2 = __mempcpy (p2, tmp, SWAP_GENERIC_SIZE); |
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| 33 | n -= SWAP_GENERIC_SIZE; |
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| 34 | } |
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| 35 | while (n > 0) |
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| 36 | { |
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| 37 | unsigned char t = ((unsigned char *)p1)[--n]; |
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| 38 | ((unsigned char *)p1)[n] = ((unsigned char *)p2)[n]; |
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| 39 | ((unsigned char *)p2)[n] = t; |
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| 40 | } |
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| 41 | } |
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| 42 | |
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