1 | /* |
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2 | (C) Copyright 2001,2006, |
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3 | International Business Machines Corporation, |
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4 | Sony Computer Entertainment, Incorporated, |
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5 | Toshiba Corporation, |
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6 | |
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7 | All rights reserved. |
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8 | |
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9 | Redistribution and use in source and binary forms, with or without |
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10 | modification, are permitted provided that the following conditions are met: |
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11 | |
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12 | * Redistributions of source code must retain the above copyright notice, |
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13 | this list of conditions and the following disclaimer. |
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14 | * Redistributions in binary form must reproduce the above copyright |
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15 | notice, this list of conditions and the following disclaimer in the |
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16 | documentation and/or other materials provided with the distribution. |
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17 | * Neither the names of the copyright holders nor the names of their |
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18 | contributors may be used to endorse or promote products derived from this |
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19 | software without specific prior written permission. |
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20 | |
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21 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" |
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22 | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
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23 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
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24 | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
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25 | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
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26 | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
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27 | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
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28 | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
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29 | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
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30 | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
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31 | POSSIBILITY OF SUCH DAMAGE. |
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32 | */ |
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33 | #include <spu_intrinsics.h> |
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34 | #include <stddef.h> |
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35 | |
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36 | /* Scans the string pointed to by s for the character c and |
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37 | * returns a pointer to the first occurance of c. If |
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38 | * c is not found, then NULL is returned. |
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39 | */ |
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40 | char *strchr(const char *s, int c) |
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41 | { |
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42 | unsigned int cmp, skip; |
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43 | vec_uchar16 *ptr, data, vc; |
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44 | vec_uint4 cmp_c, cmp_0; |
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45 | vec_uint4 result; |
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46 | vec_uint4 mask; |
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47 | vec_uint4 one = spu_splats(0xffffU); |
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48 | /* Scan memory array a quadword at a time. Skip leading |
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49 | * mis-aligned bytes. |
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50 | */ |
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51 | ptr = (vec_uchar16 *)s; |
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52 | |
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53 | skip = (unsigned int)(ptr) & 15; |
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54 | mask = spu_rlmask(one, -skip); |
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55 | |
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56 | vc = spu_splats((unsigned char)(c)); |
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57 | |
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58 | data = *ptr++; |
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59 | |
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60 | cmp_c = spu_and(spu_gather(spu_cmpeq(data, vc)), mask); |
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61 | cmp_0 = spu_and(spu_gather(spu_cmpeq(data, 0)), mask); |
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62 | |
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63 | cmp = spu_extract(spu_or(cmp_c, cmp_0), 0); |
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64 | |
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65 | while (cmp == 0) { |
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66 | data = *ptr++; |
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67 | cmp_c = spu_gather(spu_cmpeq(data, vc)); |
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68 | cmp_0 = spu_gather(spu_cmpeq(data, 0)); |
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69 | |
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70 | cmp = spu_extract(spu_or(cmp_c, cmp_0), 0); |
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71 | } |
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72 | |
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73 | /* Compute the location of the first character. If it is beyond |
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74 | * the end of the string, then return NULL. |
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75 | */ |
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76 | result = spu_add(spu_promote((unsigned int)ptr - (skip+32), 0), |
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77 | spu_cntlz(spu_promote(cmp, 0))); |
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78 | |
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79 | result = spu_andc(result, spu_cmpgt(cmp_0, cmp_c)); |
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80 | |
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81 | return ((char *)spu_extract(result, 0)); |
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82 | } |
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