| 1 | /* |
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| 2 | (C) Copyright 2008 |
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| 3 | International Business Machines Corporation, |
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| 4 | All rights reserved. |
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| 5 | |
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| 6 | Redistribution and use in source and binary forms, with or without |
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| 7 | modification, are permitted provided that the following conditions are met: |
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| 8 | |
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| 9 | * Redistributions of source code must retain the above copyright notice, |
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| 10 | this list of conditions and the following disclaimer. |
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| 11 | * Redistributions in binary form must reproduce the above copyright |
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| 12 | notice, this list of conditions and the following disclaimer in the |
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| 13 | documentation and/or other materials provided with the distribution. |
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| 14 | * Neither the names of the copyright holders nor the names of their |
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| 15 | contributors may be used to endorse or promote products derived from |
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| 16 | this software without specific prior written permission. |
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| 17 | |
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| 18 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS |
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| 19 | IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
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| 20 | TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A |
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| 21 | PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER |
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| 22 | OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
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| 23 | EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
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| 24 | PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
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| 25 | PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
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| 26 | LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
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| 27 | NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
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| 28 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
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| 29 | */ |
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| 30 | |
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| 31 | #include <spu_intrinsics.h> |
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| 32 | #include "vec_literal.h" |
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| 33 | |
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| 34 | /* |
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| 35 | * Supply the inline _straddr for use by strncpy and strncat. |
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| 36 | * |
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| 37 | * _straddr: search the string s, and return the address of the first byte |
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| 38 | * containing zero. |
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| 39 | */ |
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| 40 | static inline char *_straddr(const char *s) |
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| 41 | { |
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| 42 | unsigned int cnt, cmp, skip, mask; |
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| 43 | vec_uchar16 *ptr, data; |
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| 44 | |
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| 45 | /* |
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| 46 | * Compensate for unaligned strings. |
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| 47 | */ |
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| 48 | ptr = (vec_uchar16 *)s; /* implicit (s & ~0xf) */ |
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| 49 | skip = (unsigned int)(ptr) & 0xf; |
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| 50 | /* |
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| 51 | * skip the first skip bytes starting at (s & ~0xf). |
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| 52 | */ |
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| 53 | mask = 0xFFFF >> skip; |
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| 54 | |
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| 55 | data = *ptr; |
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| 56 | cmp = spu_extract(spu_gather(spu_cmpeq(data, 0)), 0); |
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| 57 | cmp &= mask; |
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| 58 | |
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| 59 | cnt = spu_extract(spu_cntlz(spu_promote(cmp, 0)), 0); |
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| 60 | |
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| 61 | while (cnt == 32) { |
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| 62 | data = *++ptr; |
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| 63 | cnt = spu_extract(spu_cntlz(spu_gather(spu_cmpeq(data, 0))), 0); |
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| 64 | /* |
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| 65 | * The first 16 bits for gather on a byte vector are zero, so if cnt |
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| 66 | * is 32, none of the 16 bytes in data was zero. And, there are (cnt - |
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| 67 | * 16) non-zero bytes in data. |
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| 68 | */ |
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| 69 | } |
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| 70 | /* |
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| 71 | * The first non-zero byte is at ptr aligned down plus the number of |
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| 72 | * non-zero bytes seen. |
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| 73 | */ |
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| 74 | return ((char*) (((int) ptr & ~0xf) + (cnt - 16))); |
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| 75 | } |
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