1 | /* -------------------------------------------------------------- */ |
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2 | /* (C)Copyright 2007,2008, */ |
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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 */ |
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7 | /* without modification, are permitted provided that the */ |
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8 | /* following conditions are met: */ |
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9 | /* */ |
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10 | /* - Redistributions of source code must retain the above copyright*/ |
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11 | /* notice, this list of conditions and the following disclaimer. */ |
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12 | /* */ |
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13 | /* - Redistributions in binary form must reproduce the above */ |
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14 | /* copyright notice, this list of conditions and the following */ |
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15 | /* disclaimer in the documentation and/or other materials */ |
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16 | /* provided with the distribution. */ |
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17 | /* */ |
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18 | /* - Neither the name of IBM Corporation nor the names of its */ |
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19 | /* contributors may be used to endorse or promote products */ |
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20 | /* derived from this software without specific prior written */ |
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21 | /* permission. */ |
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22 | /* */ |
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23 | /* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND */ |
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24 | /* CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, */ |
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25 | /* INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF */ |
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26 | /* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE */ |
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27 | /* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR */ |
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28 | /* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, */ |
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29 | /* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT */ |
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30 | /* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; */ |
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31 | /* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) */ |
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32 | /* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN */ |
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33 | /* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR */ |
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34 | /* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, */ |
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35 | /* EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ |
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36 | /* -------------------------------------------------------------- */ |
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37 | /* PROLOG END TAG zYx */ |
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38 | #ifdef __SPU__ |
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39 | #ifndef _ATAN2D2_H_ |
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40 | #define _ATAN2D2_H_ 1 |
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41 | |
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42 | #include <spu_intrinsics.h> |
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43 | |
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44 | #include "divd2.h" |
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45 | #include "atand2.h" |
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46 | |
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47 | /* |
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48 | * FUNCTION |
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49 | * vector double _atan2d2(vector double y, vector double x) |
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50 | * |
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51 | * DESCRIPTION |
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52 | * The atan2d2 function returns a vector containing the angles |
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53 | * whose tangets are y/x for the corresponding elements of the |
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54 | * input vectors. |
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55 | * |
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56 | * The reason this function exists is to use the signs of the |
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57 | * arguments to determine the quadrant of the result. Consider |
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58 | * sin(x)/cos(x) on the domain (-pi, pi]. Four quadrants are |
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59 | * defined by the signs of sin and cos on this domain. |
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60 | * |
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61 | * Special Cases: |
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62 | * - If the corresponding elements of x and y are zero, the |
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63 | * resulting element is undefined. |
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64 | * |
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65 | */ |
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66 | |
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67 | static __inline vector double _atan2d2(vector double y, vector double x) |
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68 | { |
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69 | vec_uchar16 dup_even = ((vec_uchar16) { 0,1,2,3, 0,1,2,3, 8,9,10,11, 8,9,10,11 }); |
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70 | vector double pi = spu_splats(SM_PI); |
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71 | vector unsigned long long ones = spu_splats(0xFFFFFFFFFFFFFFFFull); |
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72 | vector unsigned long long quad1; |
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73 | vector unsigned long long quad4; |
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74 | vector double result; |
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75 | |
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76 | vector unsigned long long xlt0; |
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77 | vector unsigned long long yge0; |
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78 | vector unsigned long long ylt0; |
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79 | |
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80 | xlt0 = (vec_ullong2)spu_rlmaska((vec_int4)spu_shuffle(x,x,dup_even), 31); |
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81 | ylt0 = (vec_ullong2)spu_rlmaska((vec_int4)spu_shuffle(y,y,dup_even), 31); |
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82 | yge0 = spu_xor(ylt0, ones); |
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83 | |
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84 | quad1 = spu_and(ylt0, xlt0); |
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85 | quad4 = spu_and(yge0, xlt0); |
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86 | |
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87 | result = _atand2(_divd2(y,x)); |
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88 | |
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89 | result = spu_sel(result, spu_sub(result, pi), quad1); |
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90 | result = spu_sel(result, spu_add(result, pi), quad4); |
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91 | |
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92 | return result; |
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93 | } |
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94 | |
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95 | #endif /* _ATAN2D2_H_ */ |
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96 | #endif /* __SPU__ */ |
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