| 1 | /* |
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| 2 | * This file is subject to the terms and conditions of the GNU General Public |
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| 3 | * License. See the file COPYING in the main directory of this archive |
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| 4 | * for more details. |
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| 5 | */ |
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| 6 | |
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| 7 | #include <linux/module.h> |
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| 8 | #include <linux/string.h> |
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| 9 | |
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| 10 | void *memmove(void *dest, const void *src, size_t n) |
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| 11 | { |
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| 12 | void *xdest = dest; |
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| 13 | size_t temp; |
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| 14 | |
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| 15 | if (!n) |
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| 16 | return xdest; |
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| 17 | |
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| 18 | if (dest < src) { |
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| 19 | if ((long)dest & 1) { |
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| 20 | char *cdest = dest; |
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| 21 | const char *csrc = src; |
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| 22 | *cdest++ = *csrc++; |
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| 23 | dest = cdest; |
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| 24 | src = csrc; |
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| 25 | n--; |
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| 26 | } |
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| 27 | if (n > 2 && (long)dest & 2) { |
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| 28 | short *sdest = dest; |
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| 29 | const short *ssrc = src; |
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| 30 | *sdest++ = *ssrc++; |
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| 31 | dest = sdest; |
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| 32 | src = ssrc; |
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| 33 | n -= 2; |
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| 34 | } |
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| 35 | temp = n >> 2; |
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| 36 | if (temp) { |
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| 37 | long *ldest = dest; |
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| 38 | const long *lsrc = src; |
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| 39 | temp--; |
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| 40 | do |
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| 41 | *ldest++ = *lsrc++; |
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| 42 | while (temp--); |
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| 43 | dest = ldest; |
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| 44 | src = lsrc; |
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| 45 | } |
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| 46 | if (n & 2) { |
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| 47 | short *sdest = dest; |
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| 48 | const short *ssrc = src; |
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| 49 | *sdest++ = *ssrc++; |
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| 50 | dest = sdest; |
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| 51 | src = ssrc; |
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| 52 | } |
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| 53 | if (n & 1) { |
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| 54 | char *cdest = dest; |
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| 55 | const char *csrc = src; |
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| 56 | *cdest = *csrc; |
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| 57 | } |
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| 58 | } else { |
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| 59 | dest = (char *)dest + n; |
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| 60 | src = (const char *)src + n; |
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| 61 | if ((long)dest & 1) { |
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| 62 | char *cdest = dest; |
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| 63 | const char *csrc = src; |
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| 64 | *--cdest = *--csrc; |
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| 65 | dest = cdest; |
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| 66 | src = csrc; |
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| 67 | n--; |
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| 68 | } |
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| 69 | if (n > 2 && (long)dest & 2) { |
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| 70 | short *sdest = dest; |
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| 71 | const short *ssrc = src; |
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| 72 | *--sdest = *--ssrc; |
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| 73 | dest = sdest; |
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| 74 | src = ssrc; |
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| 75 | n -= 2; |
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| 76 | } |
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| 77 | temp = n >> 2; |
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| 78 | if (temp) { |
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| 79 | long *ldest = dest; |
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| 80 | const long *lsrc = src; |
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| 81 | temp--; |
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| 82 | do |
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| 83 | *--ldest = *--lsrc; |
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| 84 | while (temp--); |
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| 85 | dest = ldest; |
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| 86 | src = lsrc; |
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| 87 | } |
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| 88 | if (n & 2) { |
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| 89 | short *sdest = dest; |
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| 90 | const short *ssrc = src; |
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| 91 | *--sdest = *--ssrc; |
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| 92 | dest = sdest; |
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| 93 | src = ssrc; |
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| 94 | } |
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| 95 | if (n & 1) { |
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| 96 | char *cdest = dest; |
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| 97 | const char *csrc = src; |
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| 98 | *--cdest = *--csrc; |
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| 99 | } |
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| 100 | } |
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| 101 | return xdest; |
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| 102 | } |
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| 103 | EXPORT_SYMBOL(memmove); |
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| 104 | |
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