[469] | 1 | /*************************************************************************/ |
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| 2 | /* */ |
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| 3 | /* Copyright (c) 1994 Stanford University */ |
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| 4 | /* */ |
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| 5 | /* All rights reserved. */ |
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| 6 | /* */ |
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| 7 | /* Permission is given to use, copy, and modify this software for any */ |
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| 8 | /* non-commercial purpose as long as this copyright notice is not */ |
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| 9 | /* removed. All other uses, including redistribution in whole or in */ |
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| 10 | /* part, are forbidden without prior written permission. */ |
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| 11 | /* */ |
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| 12 | /* This software is provided with absolutely no warranty and no */ |
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| 13 | /* support. */ |
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| 14 | /* */ |
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| 15 | /*************************************************************************/ |
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| 16 | |
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| 17 | /////////////////////////////////////////////////////////////////////////// |
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| 18 | // This port of the SPLASH FFT benchmark on the ALMOS-MKH OS has been |
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| 19 | // done by Alain Greiner (august 2018). |
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| 20 | // |
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| 21 | // This application performs the 1D fast Fourier transfom for an array |
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| 22 | // of N complex points, using the Cooley-Tuckey FFT method. |
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| 23 | // The N data points are seen as a 2D array (rootN rows * rootN columns). |
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[637] | 24 | // Each thread handle (rootN / nthreads) rows. |
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| 25 | // The N input data points can be initialised in three different modes: |
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[469] | 26 | // - CONSTANT : all data points have the same [1,0] value |
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| 27 | // - COSIN : data point n has [cos(n/N) , sin(n/N)] values |
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| 28 | // - RANDOM : data points have pseudo random values |
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| 29 | // |
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[628] | 30 | // The main parameters for this generic application are the following: |
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| 31 | // - M : N = 2**M = number of data points / M must be an even number. |
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| 32 | // - T : nthreads = ncores defined by the hardware / must be power of 2. |
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[637] | 33 | // The number of threads cannot be larger than the number of rows. |
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[628] | 34 | // |
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[637] | 35 | // This application uses 3 shared data arrays, that are dynamically |
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| 36 | // allocated and distributed in clusters, with one sub-buffer per cluster: |
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| 37 | // - data[N] contains N input data points, |
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| 38 | // - trans[N] contains N intermediate data points, |
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| 39 | // - twid[N] contains N coefs : exp(2*pi*i*j/N) / i and j in [0,rootN-1] |
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| 40 | // Each sub-buffer contains (N/nclusters) entries, with 2 double per entry. |
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| 41 | // These distributed buffers are allocated and initialised in parallel |
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| 42 | // by the working threads running on core 0 in each cluster. |
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[469] | 43 | // |
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[637] | 44 | // Each working thread allocates also a private coefs[rootN-1] buffer, |
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| 45 | // that contains all coefs required for a rootN points FFT. |
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[469] | 46 | // |
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[637] | 47 | // There is one working thread per core. |
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| 48 | // The actual number of cores and cluster in a given hardware architecture |
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| 49 | // is obtained by the get_config() syscall (x_size, y_size, ncores). |
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| 50 | // The max number of clusters is bounded by (X_MAX * Y_MAX). |
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| 51 | // The max number of cores per cluster is bounded by CORES_MAX. |
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| 52 | // |
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[469] | 53 | // Several configuration parameters can be defined below: |
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[574] | 54 | // - PRINT_ARRAY : Print out complex data points arrays. |
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| 55 | // - CHECK : Perform both FFT and inverse FFT to check output/input. |
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| 56 | // - DEBUG_MAIN : Display intermediate results in main() |
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| 57 | // - DEBUG_FFT1D : Display intermediate results in FFT1D() |
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[628] | 58 | // - DEBUG_ROW : Display intermedite results in FFTrow() |
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[469] | 59 | // |
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| 60 | // Regarding final instrumentation: |
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| 61 | // - the sequencial initialisation time (init_time) is computed |
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| 62 | // by the main thread in the main() function. |
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| 63 | // - The parallel execution time (parallel_time[i]) is computed by each |
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[637] | 64 | // working thread(i) in the work() function. |
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[469] | 65 | // - The synchronisation time related to the barriers (sync_time[i]) |
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[637] | 66 | // is computed by each thread(i) in the work() function. |
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[469] | 67 | // The results are displayed on the TXT terminal, and registered on disk. |
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| 68 | /////////////////////////////////////////////////////////////////////////// |
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| 69 | |
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| 70 | #include <math.h> |
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| 71 | #include <stdio.h> |
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| 72 | #include <stdlib.h> |
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| 73 | #include <fcntl.h> |
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| 74 | #include <unistd.h> |
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| 75 | #include <pthread.h> |
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| 76 | #include <almosmkh.h> |
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| 77 | #include <hal_macros.h> |
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| 78 | |
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| 79 | // constants |
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| 80 | |
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| 81 | #define PI 3.14159265359 |
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| 82 | #define PAGE_SIZE 4096 |
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| 83 | #define X_MAX 16 // max number of clusters in a row |
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| 84 | #define Y_MAX 16 // max number of clusters in a column |
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| 85 | #define CORES_MAX 4 // max number of cores in a cluster |
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| 86 | #define CLUSTERS_MAX X_MAX * Y_MAX |
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| 87 | #define THREADS_MAX CLUSTERS_MAX * CORES_MAX |
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| 88 | #define RANDOM 0 |
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| 89 | #define COSIN 1 |
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| 90 | #define CONSTANT 2 |
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| 91 | |
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| 92 | // parameters |
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| 93 | |
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[637] | 94 | #define DEFAULT_M 14 // 16384 data points |
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| 95 | #define USE_DQT_BARRIER 1 // use DDT barrier if non zero |
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[628] | 96 | #define MODE COSIN // DATA array initialisation mode |
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| 97 | #define CHECK 0 |
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[637] | 98 | #define DEBUG_MAIN 1 // trace main() function (detailed if odd) |
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| 99 | #define DEBUG_WORK 1 // trace work() function (detailed if odd) |
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[628] | 100 | #define DEBUG_FFT1D 0 // trace FFT1D() function (detailed if odd) |
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[574] | 101 | #define DEBUG_ROW 0 // trace FFTRow() function (detailed if odd) |
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| 102 | #define PRINT_ARRAY 0 |
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[469] | 103 | |
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| 104 | // macro to swap two variables |
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| 105 | #define SWAP(a,b) { double tmp; tmp = a; a = b; b = tmp; } |
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| 106 | |
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[588] | 107 | ///////////////////////////////////////////////////////////////////////////////////// |
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[637] | 108 | // FFT specific global variables |
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[588] | 109 | ///////////////////////////////////////////////////////////////////////////////////// |
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| 110 | |
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[637] | 111 | // work function arguments |
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| 112 | typedef struct work_args_s |
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[588] | 113 | { |
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[637] | 114 | unsigned int tid; // thread continuous index |
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| 115 | unsigned int lid; // core local index |
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| 116 | unsigned int cid; // cluster continuous index |
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| 117 | pthread_barrier_t * parent_barrier; // parent barrier to signal completion |
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[588] | 118 | } |
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[637] | 119 | work_args_t; |
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[588] | 120 | |
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[473] | 121 | unsigned int nthreads; // total number of threads (one thread per core) |
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| 122 | unsigned int nclusters; // total number of clusters |
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| 123 | unsigned int M = DEFAULT_M; // log2(number of points) |
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| 124 | unsigned int N; // number of points (N = 2^M) |
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| 125 | unsigned int rootN; // rootN = 2^M/2 |
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| 126 | unsigned int rows_per_thread; // number of data "rows" handled by a single thread |
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| 127 | unsigned int points_per_cluster; // number of data points per cluster |
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[469] | 128 | |
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| 129 | // arrays of pointers on distributed buffers (one sub-buffer per cluster) |
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| 130 | double * data[CLUSTERS_MAX]; // original time-domain data |
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| 131 | double * trans[CLUSTERS_MAX]; // used as auxiliary space for transpose |
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[637] | 132 | double * twid[CLUSTERS_MAX]; // twiddle factor : exp(-2iPI*k*n/N) |
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[469] | 133 | double * bloup[CLUSTERS_MAX]; // used as auxiliary space for DFT |
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| 134 | |
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| 135 | // instrumentation counters |
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[588] | 136 | unsigned int parallel_time[THREADS_MAX]; // total computation time (per thread) |
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| 137 | unsigned int sync_time[THREADS_MAX]; // cumulated waiting time in barriers (per thread) |
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| 138 | unsigned int init_time; // initialisation time (in main) |
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[469] | 139 | |
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| 140 | // synchronisation barrier (all threads) |
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| 141 | pthread_barrier_t barrier; |
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[628] | 142 | pthread_barrierattr_t barrier_attr; |
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[469] | 143 | |
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[637] | 144 | ///////////////////////////////////////////////////////////////////////////////////// |
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| 145 | // Global variables required by parallel_pthread_create() |
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| 146 | ///////////////////////////////////////////////////////////////////////////////////// |
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[469] | 147 | |
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[637] | 148 | // 2D arrays of input arguments for the <work> threads |
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| 149 | // These arrays are initialised by the application main thread |
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| 150 | |
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| 151 | work_args_t work_args[CLUSTERS_MAX][CORES_MAX]; // work function arguments |
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| 152 | work_args_t * work_ptrs[CLUSTERS_MAX][CORES_MAX]; // pointers on arguments |
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| 153 | |
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| 154 | // 1D array of barriers to allow the <work> threads to signal termination |
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| 155 | // this array is initialised in each cluster by the <build[cxy][0]> thread |
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| 156 | |
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| 157 | pthread_barrier_t parent_barriers[CLUSTERS_MAX]; // termination barrier |
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| 158 | |
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| 159 | ///////////////////////////////////////////////////////////////////////////////////// |
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[469] | 160 | // functions declaration |
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[637] | 161 | ///////////////////////////////////////////////////////////////////////////////////// |
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[469] | 162 | |
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[637] | 163 | void work( work_args_t * args ); |
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[469] | 164 | |
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[503] | 165 | double CheckSum( void ); |
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[469] | 166 | |
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[637] | 167 | void InitD( double ** data , |
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| 168 | unsigned int mode, |
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| 169 | unsigned int tid ); |
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[469] | 170 | |
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[637] | 171 | void InitT( double ** twid, |
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| 172 | unsigned int tid ); |
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[469] | 173 | |
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[637] | 174 | void InitU( double * coefs ); |
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[469] | 175 | |
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[473] | 176 | unsigned int BitReverse( unsigned int k ); |
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[469] | 177 | |
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[473] | 178 | void FFT1D( int direction, |
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| 179 | double ** x, |
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| 180 | double ** tmp, |
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| 181 | double * upriv, |
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| 182 | double ** twid, |
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[637] | 183 | unsigned int tid, |
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[473] | 184 | unsigned int MyFirst, |
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| 185 | unsigned int MyLast ); |
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[469] | 186 | |
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[473] | 187 | void TwiddleOneCol( int direction, |
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| 188 | unsigned int j, |
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| 189 | double ** u, |
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| 190 | double ** x, |
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| 191 | unsigned int offset_x ); |
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[469] | 192 | |
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[473] | 193 | void Scale( double ** x, |
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| 194 | unsigned int offset_x ); |
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[469] | 195 | |
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[473] | 196 | void Transpose( double ** src, |
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| 197 | double ** dest, |
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| 198 | unsigned int MyFirst, |
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| 199 | unsigned int MyLast ); |
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[469] | 200 | |
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[473] | 201 | void Copy( double ** src, |
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| 202 | double ** dest, |
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| 203 | unsigned int MyFirst, |
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| 204 | unsigned int MyLast ); |
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[469] | 205 | |
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[473] | 206 | void Reverse( double ** x, |
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| 207 | unsigned int offset_x ); |
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[469] | 208 | |
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[574] | 209 | void FFTRow( int direction, |
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[473] | 210 | double * u, |
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| 211 | double ** x, |
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| 212 | unsigned int offset_x ); |
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[469] | 213 | |
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[473] | 214 | void PrintArray( double ** x, |
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| 215 | unsigned int size ); |
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[469] | 216 | |
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[473] | 217 | void SimpleDft( int direction, |
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| 218 | unsigned int size, |
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| 219 | double ** src, |
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| 220 | unsigned int src_offset, |
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| 221 | double ** dst, |
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| 222 | unsigned int dst_offset ); |
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[469] | 223 | |
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| 224 | /////////////////////////////////////////////////////////////////// |
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| 225 | // This main() function execute the sequencial initialisation |
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| 226 | // launch the parallel execution, and makes the instrumentation. |
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| 227 | /////////////////////////////////////////////////////////////////// |
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[503] | 228 | void main ( void ) |
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[469] | 229 | { |
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[628] | 230 | int error; |
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| 231 | |
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[637] | 232 | unsigned int x_size; // number of clusters per row |
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| 233 | unsigned int y_size; // number of clusters per column |
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| 234 | unsigned int ncores; // max number of cores per cluster |
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[469] | 235 | |
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| 236 | unsigned int x; // current index for cluster X coordinate |
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| 237 | unsigned int y; // current index for cluster Y coordinate |
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| 238 | unsigned int lid; // current index for core in a cluster |
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[637] | 239 | unsigned int tid; // continuous thread index |
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| 240 | unsigned int cid; // cluster continuous index |
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[469] | 241 | unsigned int cxy; // hardware specific cluster identifier |
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| 242 | |
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[637] | 243 | char name[64]; // instrumentation file name |
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| 244 | char path[128]; // instrumentation path name |
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| 245 | char string[256]; |
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| 246 | int ret; |
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| 247 | |
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[469] | 248 | unsigned long long start_init_cycle; |
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[588] | 249 | unsigned long long end_init_cycle; |
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[469] | 250 | |
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[637] | 251 | #if DEBUG_MAIN |
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| 252 | unsigned long long debug_cycle; |
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| 253 | #endif |
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| 254 | |
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[469] | 255 | #if CHECK |
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[637] | 256 | double ck1; // for input/output checking |
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| 257 | double ck3; // for input/output checking |
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[469] | 258 | #endif |
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| 259 | |
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| 260 | // get FFT application start cycle |
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[588] | 261 | get_cycle( &start_init_cycle ); |
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[469] | 262 | |
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[637] | 263 | // get platform parameters |
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[469] | 264 | if( get_config( &x_size , &y_size , &ncores ) ) |
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| 265 | { |
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[628] | 266 | printf("\n[fft error] cannot get hardware configuration\n"); |
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[469] | 267 | exit( 0 ); |
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| 268 | } |
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| 269 | |
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| 270 | // check ncores |
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| 271 | if( (ncores != 1) && (ncores != 2) && (ncores != 4) ) |
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| 272 | { |
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[628] | 273 | printf("\n[fft error] number of cores per cluster must be 1/2/4\n"); |
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[469] | 274 | exit( 0 ); |
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| 275 | } |
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| 276 | |
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| 277 | // check x_size |
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| 278 | if( (x_size != 1) && (x_size != 2) && (x_size != 4) && (x_size != 8) && (x_size != 16) ) |
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| 279 | { |
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[628] | 280 | printf("\n[fft error] x_size must be 1/2/4/8/16\n"); |
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[469] | 281 | exit( 0 ); |
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| 282 | } |
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| 283 | |
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| 284 | // check y_size |
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| 285 | if( (y_size != 1) && (y_size != 2) && (y_size != 4) && (y_size != 8) && (y_size != 16) ) |
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| 286 | { |
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[628] | 287 | printf("\n[fft error] y_size must be 1/2/4/8/16\n"); |
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[469] | 288 | exit( 0 ); |
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| 289 | } |
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| 290 | |
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[637] | 291 | // compute nthreads and nclusters |
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[469] | 292 | nthreads = x_size * y_size * ncores; |
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| 293 | nclusters = x_size * y_size; |
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| 294 | |
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[637] | 295 | // compute covering DQT size an level |
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| 296 | unsigned int z = (x_size > y_size) ? x_size : y_size; |
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| 297 | unsigned int root_level = (z == 1) ? 0 : (z == 2) ? 1 : (z == 4) ? 2 : (z == 8) ? 3 : 4; |
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| 298 | |
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[469] | 299 | // compute various constants depending on N and T |
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| 300 | N = 1 << M; |
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| 301 | rootN = 1 << (M / 2); |
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| 302 | rows_per_thread = rootN / nthreads; |
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| 303 | points_per_cluster = N / nclusters; |
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| 304 | |
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| 305 | // check N versus T |
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| 306 | if( rootN < nthreads ) |
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| 307 | { |
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[628] | 308 | printf("\n[fft error] sqrt(N) must be larger than T\n"); |
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[469] | 309 | exit( 0 ); |
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| 310 | } |
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| 311 | |
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[637] | 312 | printf("\n[fft] starts / %d points / %d thread(s) / PID %x / cycle %d\n", |
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| 313 | N, nthreads, getpid(), (unsigned int)start_init_cycle ); |
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[469] | 314 | |
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[637] | 315 | // build instrumentation file name |
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| 316 | if( USE_DQT_BARRIER ) |
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| 317 | snprintf( name , 64 , "p_fft_dqt_%d_%d_%d", N , x_size * y_size , ncores ); |
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| 318 | else |
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| 319 | snprintf( name , 64 , "p_fft_smp_%d_%d_%d", N , x_size * y_size , ncores ); |
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[469] | 320 | |
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[637] | 321 | // build pathname |
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| 322 | snprintf( path , 128 , "/home/%s", name ); |
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| 323 | |
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| 324 | // open instrumentation file |
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| 325 | FILE * f = fopen( path , NULL ); |
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| 326 | if ( f == NULL ) |
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| 327 | { |
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| 328 | printf("\n[fft error] cannot open instrumentation file <%s>\n", path ); |
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| 329 | exit( 0 ); |
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[469] | 330 | } |
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| 331 | |
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[635] | 332 | #if DEBUG_MAIN |
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[637] | 333 | get_cycle( &debug_cycle ); |
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| 334 | printf("\n[fft] main open file <%s> at cycle %d\n", |
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| 335 | path, (unsigned int)debug_cycle ); |
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[635] | 336 | #endif |
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[574] | 337 | |
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[469] | 338 | #if CHECK |
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[473] | 339 | ck1 = CheckSum(); |
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[469] | 340 | #endif |
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| 341 | |
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[574] | 342 | #if PRINT_ARRAY |
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[469] | 343 | printf("\nData values / base = %x\n", &data[0][0] ); |
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| 344 | PrintArray( data , N ); |
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| 345 | |
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| 346 | printf("\nTwiddle values / base = %x\n", &twid[0][0] ); |
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| 347 | PrintArray( twid , N ); |
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| 348 | |
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| 349 | SimpleDft( 1 , N , data , 0 , bloup , 0 ); |
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| 350 | |
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| 351 | printf("\nExpected results / base = %x\n", &bloup[0][0] ); |
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| 352 | PrintArray( bloup , N ); |
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| 353 | #endif |
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| 354 | |
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[637] | 355 | // initialise barrier synchronizing all <work> threads |
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[628] | 356 | if( USE_DQT_BARRIER ) |
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[473] | 357 | { |
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[628] | 358 | barrier_attr.x_size = x_size; |
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| 359 | barrier_attr.y_size = y_size; |
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| 360 | barrier_attr.nthreads = ncores; |
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| 361 | error = pthread_barrier_init( &barrier, &barrier_attr , nthreads ); |
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| 362 | } |
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| 363 | else |
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| 364 | { |
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| 365 | error = pthread_barrier_init( &barrier, NULL , nthreads ); |
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| 366 | } |
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| 367 | |
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| 368 | if( error ) |
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| 369 | { |
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| 370 | printf("\n[fft error] cannot initialize barrier\n"); |
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[473] | 371 | exit( 0 ); |
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| 372 | } |
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[469] | 373 | |
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[635] | 374 | #if DEBUG_MAIN |
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[637] | 375 | get_cycle( &debug_cycle ); |
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| 376 | printf("\n[fft] main completes barrier init at cycle %d\n", |
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| 377 | (unsigned int)debug_cycle ); |
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[635] | 378 | #endif |
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[473] | 379 | |
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[637] | 380 | // build array of arguments for the <work> threads |
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[469] | 381 | for (x = 0 ; x < x_size ; x++) |
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| 382 | { |
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| 383 | for (y = 0 ; y < y_size ; y++) |
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| 384 | { |
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[588] | 385 | // compute cluster identifier |
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| 386 | cxy = HAL_CXY_FROM_XY( x , y ); |
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| 387 | |
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[469] | 388 | for ( lid = 0 ; lid < ncores ; lid++ ) |
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| 389 | { |
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[637] | 390 | // compute cluster continuous index |
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| 391 | cid = (x * y_size) + y; |
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[469] | 392 | |
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[637] | 393 | // compute work thread continuous index |
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| 394 | tid = (cid * ncores) + lid; |
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| 395 | |
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| 396 | // initialize 2D array of arguments |
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| 397 | work_args[cxy][lid].tid = tid; |
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| 398 | work_args[cxy][lid].lid = lid; |
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| 399 | work_args[cxy][lid].cid = cid; |
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| 400 | work_args[cxy][lid].parent_barrier = &parent_barriers[cxy]; |
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[469] | 401 | |
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[637] | 402 | // initialize 2D array of pointers |
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| 403 | work_ptrs[cxy][lid] = &work_args[cxy][lid]; |
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[469] | 404 | } |
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| 405 | } |
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| 406 | } |
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| 407 | |
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[637] | 408 | // register sequencial time |
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| 409 | get_cycle( &end_init_cycle ); |
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| 410 | init_time = (unsigned int)(end_init_cycle - start_init_cycle); |
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| 411 | |
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[635] | 412 | #if DEBUG_MAIN |
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[637] | 413 | printf("\n[fft] main completes <work> threads arguments at cycle %d\n", |
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| 414 | (unsigned int)end_init_cycle ); |
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[635] | 415 | #endif |
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[628] | 416 | |
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[637] | 417 | // create and execute the working threads |
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| 418 | if( pthread_parallel_create( root_level, |
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| 419 | &work, |
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| 420 | &work_ptrs[0][0], |
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| 421 | &parent_barriers[0] ) ) |
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[469] | 422 | { |
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[637] | 423 | printf("\n[fft error] creating threads\n"); |
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| 424 | exit( 0 ); |
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| 425 | } |
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[469] | 426 | |
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[637] | 427 | #if DEBUG_MAIN |
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| 428 | get_cycle( &debug_cycle ); |
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| 429 | printf("\n[fft] main resume for instrumentation at cycle %d\n", |
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| 430 | (unsigned int)debug_cycle) ; |
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[588] | 431 | #endif |
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[469] | 432 | |
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[574] | 433 | #if PRINT_ARRAY |
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[469] | 434 | printf("\nData values after FFT:\n"); |
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| 435 | PrintArray( data , N ); |
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| 436 | #endif |
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| 437 | |
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| 438 | #if CHECK |
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[473] | 439 | ck3 = CheckSum(); |
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[469] | 440 | printf("\n*** Results ***\n"); |
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| 441 | printf("Checksum difference is %f (%f, %f)\n", ck1 - ck3, ck1, ck3); |
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| 442 | if (fabs(ck1 - ck3) < 0.001) printf("Results OK\n"); |
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| 443 | else printf("Results KO\n"); |
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| 444 | #endif |
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| 445 | |
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[628] | 446 | // display header on terminal, and save to file |
---|
| 447 | printf("\n----- %s -----\n", name ); |
---|
[469] | 448 | |
---|
[628] | 449 | ret = fprintf( f , "\n----- %s -----\n", name ); |
---|
| 450 | if( ret < 0 ) |
---|
| 451 | { |
---|
| 452 | printf("\n[fft error] cannot write header to file <%s>\n", path ); |
---|
| 453 | exit(0); |
---|
| 454 | } |
---|
[469] | 455 | |
---|
[637] | 456 | // get instrumentation results for each thread |
---|
[588] | 457 | for (tid = 0 ; tid < nthreads ; tid++) |
---|
| 458 | { |
---|
[628] | 459 | snprintf( string , 256 , "- tid %d : Sequencial %d / Parallel %d / Barrier %d\n", |
---|
[588] | 460 | tid, init_time, parallel_time[tid], sync_time[tid] ); |
---|
| 461 | |
---|
[637] | 462 | // save to instrumentation file |
---|
[628] | 463 | fprintf( f , "%s" , string ); |
---|
| 464 | if( ret < 0 ) |
---|
| 465 | { |
---|
| 466 | printf("\n[fft error] cannot write thread %d to file <%s>\n", tid, path ); |
---|
[637] | 467 | printf("%s", string ); |
---|
[628] | 468 | exit(0); |
---|
| 469 | } |
---|
[588] | 470 | } |
---|
| 471 | |
---|
[637] | 472 | // compute min/max values |
---|
[628] | 473 | unsigned int min_para = parallel_time[0]; |
---|
| 474 | unsigned int max_para = parallel_time[0]; |
---|
| 475 | unsigned int min_sync = sync_time[0]; |
---|
| 476 | unsigned int max_sync = sync_time[0]; |
---|
[588] | 477 | |
---|
[630] | 478 | for (tid = 0 ; tid < nthreads ; tid++) |
---|
[469] | 479 | { |
---|
| 480 | if (parallel_time[tid] > max_para) max_para = parallel_time[tid]; |
---|
| 481 | if (parallel_time[tid] < min_para) min_para = parallel_time[tid]; |
---|
| 482 | if (sync_time[tid] > max_sync) max_sync = sync_time[tid]; |
---|
| 483 | if (sync_time[tid] < min_sync) min_sync = sync_time[tid]; |
---|
| 484 | } |
---|
| 485 | |
---|
[637] | 486 | // display MIN/MAX values on terminal and save to file |
---|
[628] | 487 | snprintf( string , 256 , "\n Sequencial Parallel Barrier\n" |
---|
[588] | 488 | "MIN : %d\t | %d\t | %d\t (cycles)\n" |
---|
| 489 | "MAX : %d\t | %d\t | %d\t (cycles)\n", |
---|
[469] | 490 | (int)init_time, (int)min_para, (int)min_sync, |
---|
| 491 | (int)init_time, (int)max_para, (int)max_sync ); |
---|
[628] | 492 | printf("%s", string ); |
---|
| 493 | ret = fprintf( f , "%s", string ); |
---|
| 494 | if( ret < 0 ) |
---|
| 495 | { |
---|
| 496 | printf("\n[fft error] cannot write MIN/MAX to file <%s>\n", path ); |
---|
| 497 | exit(0); |
---|
| 498 | } |
---|
[469] | 499 | |
---|
[628] | 500 | // close instrumentation file |
---|
| 501 | ret = fclose( f ); |
---|
| 502 | if( ret ) |
---|
| 503 | { |
---|
| 504 | printf("\n[fft error] cannot close file <%s>\n", path ); |
---|
| 505 | exit(0); |
---|
| 506 | } |
---|
[637] | 507 | |
---|
| 508 | #if DEBUG_MAIN |
---|
| 509 | get_cycle( &debug_cycle ); |
---|
| 510 | printf("\n[fft] main close file <%s> at cycle %d\n", |
---|
| 511 | path, (unsigned int)debug_cycle ); |
---|
| 512 | #endif |
---|
[469] | 513 | |
---|
[628] | 514 | exit( 0 ); |
---|
| 515 | |
---|
[469] | 516 | } // end main() |
---|
| 517 | |
---|
[637] | 518 | ///////////////////////////////////////////////////////////////// |
---|
| 519 | // This function is executed in parallel by all <work> threads. |
---|
| 520 | ///////////////////////////////////////////////////////////////// |
---|
| 521 | void work( work_args_t * args ) |
---|
[469] | 522 | { |
---|
[637] | 523 | unsigned int tid; // this thread continuous index |
---|
| 524 | unsigned int lid; // core local index |
---|
| 525 | unsigned int cid; // cluster continuous index |
---|
| 526 | pthread_barrier_t * parent_barrier; // pointer on parent barrier |
---|
[469] | 527 | |
---|
[637] | 528 | unsigned int MyFirst; // index first row allocated to thread |
---|
| 529 | unsigned int MyLast; // index last row allocated to thread |
---|
| 530 | double * upriv; // private array of FFT coefs |
---|
| 531 | |
---|
[469] | 532 | unsigned long long parallel_start; |
---|
| 533 | unsigned long long parallel_stop; |
---|
| 534 | unsigned long long barrier_start; |
---|
| 535 | unsigned long long barrier_stop; |
---|
| 536 | |
---|
[637] | 537 | // get thread arguments |
---|
| 538 | tid = args->tid; |
---|
| 539 | lid = args->lid; |
---|
| 540 | cid = args->cid; |
---|
| 541 | parent_barrier = args->parent_barrier; |
---|
[469] | 542 | |
---|
| 543 | get_cycle( ¶llel_start ); |
---|
| 544 | |
---|
[637] | 545 | #if DEBUG_WORK |
---|
[629] | 546 | printf("\n[fft] %s : thread %d enter / cycle %d\n", |
---|
[637] | 547 | __FUNCTION__, tid, (unsigned int)parallel_start ); |
---|
[588] | 548 | #endif |
---|
| 549 | |
---|
[637] | 550 | // core 0 allocate memory from the local cluster |
---|
| 551 | // for the distributed data[], trans[], twid[] buffers |
---|
| 552 | // and for the private upriv[] buffer |
---|
| 553 | if( lid == 0 ) |
---|
| 554 | { |
---|
| 555 | unsigned int data_size = (N / nclusters) * 2 * sizeof(double); |
---|
| 556 | unsigned int coefs_size = (rootN - 1) * 2 * sizeof(double); |
---|
| 557 | |
---|
| 558 | data[cid] = (double *)malloc( data_size ); |
---|
| 559 | trans[cid] = (double *)malloc( data_size ); |
---|
| 560 | twid[cid] = (double *)malloc( data_size ); |
---|
| 561 | |
---|
| 562 | upriv = (double *)malloc( coefs_size ); |
---|
| 563 | } |
---|
| 564 | |
---|
[629] | 565 | // BARRIER |
---|
| 566 | get_cycle( &barrier_start ); |
---|
| 567 | pthread_barrier_wait( &barrier ); |
---|
| 568 | get_cycle( &barrier_stop ); |
---|
[637] | 569 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
[629] | 570 | |
---|
[637] | 571 | #if DEBUG_WORK |
---|
| 572 | printf("\n[fft] %s : thread %d exit first barrier / cycle %d\n", |
---|
| 573 | __FUNCTION__, tid, (unsigned int)barrier_stop ); |
---|
[630] | 574 | #endif |
---|
[629] | 575 | |
---|
[637] | 576 | // all threads initialize data[] local array |
---|
| 577 | InitD( data , MODE , tid ); |
---|
[469] | 578 | |
---|
[637] | 579 | // all threads initialize twid[] local array |
---|
| 580 | InitT( twid , tid ); |
---|
| 581 | |
---|
| 582 | // all threads initialise private upriv[] array |
---|
| 583 | InitU( upriv ); |
---|
| 584 | |
---|
| 585 | // BARRIER |
---|
| 586 | get_cycle( &barrier_start ); |
---|
| 587 | pthread_barrier_wait( &barrier ); |
---|
| 588 | get_cycle( &barrier_stop ); |
---|
| 589 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
| 590 | |
---|
| 591 | #if DEBUG_WORK |
---|
| 592 | printf("\n[fft] %s : thread %d exit second barrier / cycle %d\n", |
---|
| 593 | __FUNCTION__, tid, (unsigned int)barrier_stop ); |
---|
| 594 | #endif |
---|
| 595 | |
---|
[469] | 596 | // compute first and last rows handled by the thread |
---|
[637] | 597 | MyFirst = rootN * tid / nthreads; |
---|
| 598 | MyLast = rootN * (tid + 1) / nthreads; |
---|
[469] | 599 | |
---|
| 600 | // perform forward FFT |
---|
[637] | 601 | FFT1D( 1 , data , trans , upriv , twid , tid , MyFirst , MyLast ); |
---|
[469] | 602 | |
---|
| 603 | #if CHECK |
---|
| 604 | get_cycle( &barrier_start ); |
---|
| 605 | pthread_barrier_wait( &barrier ); |
---|
| 606 | get_cycle( &barrier_stop ); |
---|
[637] | 607 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
| 608 | FFT1D( -1 , data , trans , upriv , twid , tid , MyFirst , MyLast ); |
---|
[469] | 609 | #endif |
---|
| 610 | |
---|
| 611 | get_cycle( ¶llel_stop ); |
---|
| 612 | |
---|
[630] | 613 | // register parallel time |
---|
[637] | 614 | parallel_time[tid] = (unsigned int)(parallel_stop - parallel_start); |
---|
[630] | 615 | |
---|
[637] | 616 | #if DEBUG_WORK |
---|
| 617 | printf("\n[fft] %s : thread %d completes fft / p_start %d / p_stop %d\n", |
---|
| 618 | __FUNCTION__, tid, (unsigned int)parallel_start, (unsigned int)parallel_stop ); |
---|
[588] | 619 | #endif |
---|
[469] | 620 | |
---|
[637] | 621 | // work thread signals completion to main |
---|
| 622 | pthread_barrier_wait( parent_barrier ); |
---|
[588] | 623 | |
---|
[637] | 624 | #if DEBUG_WORK |
---|
| 625 | printf("\n[fft] %s : thread %d exit\n", |
---|
| 626 | __FUNCTION__, tid ); |
---|
| 627 | #endif |
---|
[469] | 628 | |
---|
[637] | 629 | // work thread exit |
---|
| 630 | pthread_exit( NULL ); |
---|
| 631 | |
---|
| 632 | } // end work() |
---|
| 633 | |
---|
[469] | 634 | //////////////////////////////////////////////////////////////////////////////////////// |
---|
| 635 | // This function makes the DFT from the src[nclusters][points_per_cluster] distributed |
---|
| 636 | // buffer, to the dst[nclusters][points_per_cluster] distributed buffer. |
---|
| 637 | //////////////////////////////////////////////////////////////////////////////////////// |
---|
[473] | 638 | void SimpleDft( int direction, // 1 direct / -1 reverse |
---|
| 639 | unsigned int size, // number of points |
---|
| 640 | double ** src, // source distributed buffer |
---|
| 641 | unsigned int src_offset, // offset in source array |
---|
| 642 | double ** dst, // destination distributed buffer |
---|
| 643 | unsigned int dst_offset ) // offset in destination array |
---|
[469] | 644 | { |
---|
[473] | 645 | unsigned int n , k; |
---|
| 646 | double phi; // 2*PI*n*k/N |
---|
| 647 | double u_r; // cos( phi ) |
---|
| 648 | double u_c; // sin( phi ) |
---|
| 649 | double d_r; // Re(data[n]) |
---|
| 650 | double d_c; // Im(data[n]) |
---|
| 651 | double accu_r; // Re(accu) |
---|
| 652 | double accu_c; // Im(accu) |
---|
| 653 | unsigned int c_id; // distributed buffer cluster index |
---|
| 654 | unsigned int c_offset; // offset in distributed buffer |
---|
[469] | 655 | |
---|
| 656 | for ( k = 0 ; k < size ; k++ ) // loop on the output data points |
---|
| 657 | { |
---|
| 658 | // initialise accu |
---|
| 659 | accu_r = 0; |
---|
| 660 | accu_c = 0; |
---|
| 661 | |
---|
| 662 | for ( n = 0 ; n < size ; n++ ) // loop on the input data points |
---|
| 663 | { |
---|
| 664 | // compute coef |
---|
| 665 | phi = (double)(2*PI*n*k) / size; |
---|
| 666 | u_r = cos( phi ); |
---|
| 667 | u_c = -sin( phi ) * direction; |
---|
| 668 | |
---|
| 669 | // get input data point |
---|
| 670 | c_id = (src_offset + n) / (points_per_cluster); |
---|
| 671 | c_offset = (src_offset + n) % (points_per_cluster); |
---|
[473] | 672 | d_r = src[c_id][2*c_offset]; |
---|
| 673 | d_c = src[c_id][2*c_offset+1]; |
---|
[469] | 674 | |
---|
| 675 | // increment accu |
---|
| 676 | accu_r += ((u_r*d_r) - (u_c*d_c)); |
---|
| 677 | accu_c += ((u_r*d_c) + (u_c*d_r)); |
---|
| 678 | } |
---|
| 679 | |
---|
| 680 | // scale for inverse DFT |
---|
| 681 | if ( direction == -1 ) |
---|
| 682 | { |
---|
| 683 | accu_r /= size; |
---|
| 684 | accu_c /= size; |
---|
| 685 | } |
---|
| 686 | |
---|
| 687 | // set output data point |
---|
| 688 | c_id = (dst_offset + k) / (points_per_cluster); |
---|
| 689 | c_offset = (dst_offset + k) % (points_per_cluster); |
---|
| 690 | dst[c_id][2*c_offset] = accu_r; |
---|
| 691 | dst[c_id][2*c_offset+1] = accu_c; |
---|
| 692 | } |
---|
| 693 | |
---|
| 694 | } // end SimpleDft() |
---|
| 695 | |
---|
[582] | 696 | /////////////////////// |
---|
[503] | 697 | double CheckSum( void ) |
---|
[469] | 698 | { |
---|
[473] | 699 | unsigned int i , j; |
---|
| 700 | unsigned int c_id; |
---|
| 701 | unsigned int c_offset; |
---|
[629] | 702 | double cks; |
---|
[469] | 703 | |
---|
| 704 | cks = 0.0; |
---|
| 705 | for (j = 0; j < rootN ; j++) |
---|
| 706 | { |
---|
| 707 | for (i = 0; i < rootN ; i++) |
---|
| 708 | { |
---|
| 709 | c_id = (rootN * j + i) / (points_per_cluster); |
---|
| 710 | c_offset = (rootN * j + i) % (points_per_cluster); |
---|
| 711 | |
---|
| 712 | cks += data[c_id][2*c_offset] + data[c_id][2*c_offset+1]; |
---|
| 713 | } |
---|
| 714 | } |
---|
| 715 | return(cks); |
---|
| 716 | } |
---|
| 717 | |
---|
[637] | 718 | ////////////////////////////////////////////////////////////////////////////////////// |
---|
| 719 | // Each working thread <tid> contributes to initialize (rootN / nthreads) rows, |
---|
| 720 | // in the shared - and distributed - <data> array. |
---|
| 721 | ////////////////////////////////////////////////////////////////////////////////////// |
---|
| 722 | void InitD(double ** data, |
---|
| 723 | unsigned int mode, |
---|
| 724 | unsigned int tid ) |
---|
[469] | 725 | { |
---|
[473] | 726 | unsigned int i , j; |
---|
| 727 | unsigned int c_id; |
---|
| 728 | unsigned int c_offset; |
---|
| 729 | unsigned int index; |
---|
[469] | 730 | |
---|
[637] | 731 | // compute row_min and row_max |
---|
| 732 | unsigned int row_min = tid * rows_per_thread; |
---|
| 733 | unsigned int row_max = row_min + rows_per_thread; |
---|
| 734 | |
---|
| 735 | for ( j = row_min ; j < row_max ; j++ ) // loop on rows |
---|
[469] | 736 | { |
---|
[637] | 737 | for ( i = 0 ; i < rootN ; i++ ) // loop on points in a row |
---|
[469] | 738 | { |
---|
| 739 | index = j * rootN + i; |
---|
| 740 | c_id = index / (points_per_cluster); |
---|
| 741 | c_offset = index % (points_per_cluster); |
---|
| 742 | |
---|
| 743 | // complex input signal is random |
---|
| 744 | if ( mode == RANDOM ) |
---|
| 745 | { |
---|
[637] | 746 | data[c_id][2*c_offset] = ( (double)rand() ) / 65536; |
---|
| 747 | data[c_id][2*c_offset+1] = ( (double)rand() ) / 65536; |
---|
[469] | 748 | } |
---|
| 749 | |
---|
| 750 | |
---|
| 751 | // complex input signal is cos(n/N) / sin(n/N) |
---|
| 752 | if ( mode == COSIN ) |
---|
| 753 | { |
---|
| 754 | double phi = (double)( 2 * PI * index) / N; |
---|
[637] | 755 | data[c_id][2*c_offset] = cos( phi ); |
---|
| 756 | data[c_id][2*c_offset+1] = sin( phi ); |
---|
[469] | 757 | } |
---|
| 758 | |
---|
| 759 | // complex input signal is constant |
---|
| 760 | if ( mode == CONSTANT ) |
---|
| 761 | { |
---|
[637] | 762 | data[c_id][2*c_offset] = 1.0; |
---|
| 763 | data[c_id][2*c_offset+1] = 0.0; |
---|
[469] | 764 | } |
---|
| 765 | } |
---|
| 766 | } |
---|
| 767 | } |
---|
| 768 | |
---|
[637] | 769 | /////////////////////////////////////////////////////////////////////////////////////// |
---|
| 770 | // Each working thread <tid> contributes to initialize (rootN / nthreads) rows, |
---|
| 771 | // in the shared - and distributed - <twiddle> array. |
---|
| 772 | /////////////////////////////////////////////////////////////////////////////////////// |
---|
| 773 | void InitT( double ** twid, |
---|
| 774 | unsigned int tid ) |
---|
[469] | 775 | { |
---|
[637] | 776 | unsigned int i, j; |
---|
| 777 | unsigned int index; |
---|
[473] | 778 | unsigned int c_id; |
---|
| 779 | unsigned int c_offset; |
---|
[469] | 780 | double phi; |
---|
| 781 | |
---|
[637] | 782 | // compute row_min and row_max |
---|
| 783 | unsigned int row_min = tid * rows_per_thread; |
---|
| 784 | unsigned int row_max = row_min + rows_per_thread; |
---|
| 785 | |
---|
| 786 | for ( j = row_min ; j < row_max ; j++ ) // loop on rows |
---|
[469] | 787 | { |
---|
[637] | 788 | for ( i = 0 ; i < rootN ; i++ ) // loop on points in a row |
---|
| 789 | { |
---|
| 790 | index = j * rootN + i; |
---|
| 791 | c_id = index / (points_per_cluster); |
---|
| 792 | c_offset = index % (points_per_cluster); |
---|
[469] | 793 | |
---|
[637] | 794 | phi = (double)(2.0 * PI * i * j) / N; |
---|
| 795 | twid[c_id][2*c_offset] = cos( phi ); |
---|
| 796 | twid[c_id][2*c_offset+1] = -sin( phi ); |
---|
[469] | 797 | } |
---|
| 798 | } |
---|
| 799 | } |
---|
| 800 | |
---|
[637] | 801 | /////////////////////////////////////////////////////////////////////////////////////// |
---|
| 802 | // Each working thread initialize the private <upriv> array / (rootN - 1) entries. |
---|
| 803 | /////////////////////////////////////////////////////////////////////////////////////// |
---|
| 804 | void InitU( double * upriv ) |
---|
[469] | 805 | { |
---|
[637] | 806 | unsigned int q; |
---|
| 807 | unsigned int j; |
---|
| 808 | unsigned int base; |
---|
| 809 | unsigned int n1; |
---|
[469] | 810 | double phi; |
---|
| 811 | |
---|
[637] | 812 | for (q = 0 ; ((unsigned int)(1 << q) < N) ; q++) |
---|
[469] | 813 | { |
---|
[637] | 814 | n1 = 1 << q; // n1 == 2**q |
---|
| 815 | base = n1 - 1; |
---|
| 816 | for (j = 0; (j < n1) ; j++) |
---|
| 817 | { |
---|
| 818 | if (base + j > rootN - 1) return; |
---|
[469] | 819 | |
---|
[637] | 820 | phi = (double)(2.0 * PI * j) / (2 * n1); |
---|
| 821 | upriv[2*(base+j)] = cos( phi ); |
---|
| 822 | upriv[2*(base+j)+1] = -sin( phi ); |
---|
[469] | 823 | } |
---|
| 824 | } |
---|
| 825 | } |
---|
| 826 | |
---|
| 827 | //////////////////////////////////////////////////////////////////////////////////////// |
---|
| 828 | // This function returns an index value that is the bit reverse of the input value. |
---|
| 829 | //////////////////////////////////////////////////////////////////////////////////////// |
---|
[473] | 830 | unsigned int BitReverse( unsigned int k ) |
---|
[469] | 831 | { |
---|
[473] | 832 | unsigned int i; |
---|
| 833 | unsigned int j; |
---|
| 834 | unsigned int tmp; |
---|
[469] | 835 | |
---|
| 836 | j = 0; |
---|
| 837 | tmp = k; |
---|
| 838 | for (i = 0; i < M/2 ; i++) |
---|
| 839 | { |
---|
| 840 | j = 2 * j + (tmp & 0x1); |
---|
| 841 | tmp = tmp >> 1; |
---|
| 842 | } |
---|
| 843 | return j; |
---|
| 844 | } |
---|
| 845 | |
---|
| 846 | //////////////////////////////////////////////////////////////////////////////////////// |
---|
| 847 | // This function perform the in place (direct or inverse) FFT on the N data points |
---|
| 848 | // contained in the distributed buffers x[nclusters][points_per_cluster]. |
---|
| 849 | // It handles the (N) points 1D array as a (rootN*rootN) points 2D array. |
---|
| 850 | // 1) it transpose (rootN/nthreads ) rows from x to tmp. |
---|
| 851 | // 2) it make (rootN/nthreads) FFT on the tmp rows and apply the twiddle factor. |
---|
| 852 | // 3) it transpose (rootN/nthreads) columns from tmp to x. |
---|
| 853 | // 4) it make (rootN/nthreads) FFT on the x rows. |
---|
[574] | 854 | // It calls the FFTRow() 2*(rootN/nthreads) times to perform the in place FFT |
---|
[469] | 855 | // on the rootN points contained in a row. |
---|
| 856 | //////////////////////////////////////////////////////////////////////////////////////// |
---|
[473] | 857 | void FFT1D( int direction, // direct 1 / inverse -1 |
---|
| 858 | double ** x, // input & output distributed data points array |
---|
| 859 | double ** tmp, // auxiliary distributed data points array |
---|
| 860 | double * upriv, // local array containing coefs for rootN FFT |
---|
| 861 | double ** twid, // distributed arrays containing N twiddle factors |
---|
[637] | 862 | unsigned int tid, // thread continuous index |
---|
[473] | 863 | unsigned int MyFirst, |
---|
| 864 | unsigned int MyLast ) |
---|
[469] | 865 | { |
---|
[473] | 866 | unsigned int j; |
---|
[469] | 867 | unsigned long long barrier_start; |
---|
| 868 | unsigned long long barrier_stop; |
---|
| 869 | |
---|
[574] | 870 | #if DEBUG_FFT1D |
---|
[588] | 871 | unsigned long long cycle; |
---|
| 872 | get_cycle( &cycle ); |
---|
[629] | 873 | printf("\n[fft] %s : thread %d enter / first %d / last %d / cycle %d\n", |
---|
[637] | 874 | __FUNCTION__, tid, MyFirst, MyLast, (unsigned int)cycle ); |
---|
[574] | 875 | #endif |
---|
| 876 | |
---|
[469] | 877 | // transpose (rootN/nthreads) rows from x to tmp |
---|
| 878 | Transpose( x , tmp , MyFirst , MyLast ); |
---|
| 879 | |
---|
[574] | 880 | #if( DEBUG_FFT1D & 1 ) |
---|
| 881 | get_cycle( &cycle ); |
---|
[629] | 882 | printf("\n[fft] %s : thread %d after first transpose / cycle %d\n", |
---|
[637] | 883 | __FUNCTION__, tid, (unsigned int)cycle ); |
---|
[574] | 884 | if( PRINT_ARRAY ) PrintArray( tmp , N ); |
---|
[469] | 885 | #endif |
---|
| 886 | |
---|
| 887 | // BARRIER |
---|
| 888 | get_cycle( &barrier_start ); |
---|
| 889 | pthread_barrier_wait( &barrier ); |
---|
| 890 | get_cycle( &barrier_stop ); |
---|
[637] | 891 | sync_time[tid] = (unsigned int)(barrier_stop - barrier_start); |
---|
[469] | 892 | |
---|
[574] | 893 | #if( DEBUG_FFT1D & 1 ) |
---|
| 894 | get_cycle( &cycle ); |
---|
[629] | 895 | printf("\n[fft] %s : thread %d exit barrier after first transpose / cycle %d\n", |
---|
[637] | 896 | __FUNCTION__, tid, (unsigned int)cycle ); |
---|
[574] | 897 | #endif |
---|
| 898 | |
---|
[469] | 899 | // do FFTs on rows of tmp (i.e. columns of x) and apply twiddle factor |
---|
| 900 | for (j = MyFirst; j < MyLast; j++) |
---|
| 901 | { |
---|
[574] | 902 | FFTRow( direction , upriv , tmp , j * rootN ); |
---|
| 903 | |
---|
[469] | 904 | TwiddleOneCol( direction , j , twid , tmp , j * rootN ); |
---|
| 905 | } |
---|
| 906 | |
---|
[574] | 907 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 908 | printf("\n[fft] %s : thread %d after first twiddle\n", __FUNCTION__, tid); |
---|
[574] | 909 | if( PRINT_ARRAY ) PrintArray( tmp , N ); |
---|
[469] | 910 | #endif |
---|
| 911 | |
---|
| 912 | // BARRIER |
---|
| 913 | get_cycle( &barrier_start ); |
---|
| 914 | pthread_barrier_wait( &barrier ); |
---|
| 915 | get_cycle( &barrier_stop ); |
---|
| 916 | |
---|
[574] | 917 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 918 | printf("\n[fft] %s : thread %d exit barrier after first twiddle\n", __FUNCTION__, tid); |
---|
[574] | 919 | #endif |
---|
| 920 | |
---|
[637] | 921 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
[469] | 922 | |
---|
| 923 | // transpose tmp to x |
---|
| 924 | Transpose( tmp , x , MyFirst , MyLast ); |
---|
| 925 | |
---|
[574] | 926 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 927 | printf("\n[fft] %s : thread %d after second transpose\n", __FUNCTION__, tid); |
---|
[574] | 928 | if( PRINT_ARRAY ) PrintArray( x , N ); |
---|
[469] | 929 | #endif |
---|
| 930 | |
---|
| 931 | // BARRIER |
---|
| 932 | get_cycle( &barrier_start ); |
---|
| 933 | pthread_barrier_wait( &barrier ); |
---|
| 934 | get_cycle( &barrier_stop ); |
---|
| 935 | |
---|
[574] | 936 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 937 | printf("\n[fft] %s : thread %d exit barrier after second transpose\n", __FUNCTION__, tid); |
---|
[574] | 938 | #endif |
---|
| 939 | |
---|
[637] | 940 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
[469] | 941 | |
---|
| 942 | // do FFTs on rows of x and apply the scaling factor |
---|
| 943 | for (j = MyFirst; j < MyLast; j++) |
---|
| 944 | { |
---|
[574] | 945 | FFTRow( direction , upriv , x , j * rootN ); |
---|
[469] | 946 | if (direction == -1) Scale( x , j * rootN ); |
---|
| 947 | } |
---|
| 948 | |
---|
[574] | 949 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 950 | printf("\n[fft] %s : thread %d after FFT on rows\n", __FUNCTION__, tid); |
---|
[574] | 951 | if( PRINT_ARRAY ) PrintArray( x , N ); |
---|
[469] | 952 | #endif |
---|
| 953 | |
---|
| 954 | // BARRIER |
---|
| 955 | get_cycle( &barrier_start ); |
---|
| 956 | pthread_barrier_wait( &barrier ); |
---|
| 957 | get_cycle( &barrier_stop ); |
---|
| 958 | |
---|
[574] | 959 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 960 | printf("\n[fft] %s : thread %d exit barrier after FFT on rows\n", __FUNCTION__, tid); |
---|
[574] | 961 | #endif |
---|
[637] | 962 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
[469] | 963 | |
---|
| 964 | // transpose x to tmp |
---|
| 965 | Transpose( x , tmp , MyFirst , MyLast ); |
---|
| 966 | |
---|
[574] | 967 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 968 | printf("\n[fft] %s : thread %x after third transpose\n", __FUNCTION__, tid); |
---|
[574] | 969 | if( PRINT_ARRAY ) PrintArray( x , N ); |
---|
[469] | 970 | #endif |
---|
| 971 | |
---|
| 972 | // BARRIER |
---|
| 973 | get_cycle( &barrier_start ); |
---|
| 974 | pthread_barrier_wait( &barrier ); |
---|
| 975 | get_cycle( &barrier_stop ); |
---|
| 976 | |
---|
[574] | 977 | #if( DEBUG_FFT1D & 1 ) |
---|
[637] | 978 | printf("\n[fft] %s : thread %d exit barrier after third transpose\n", __FUNCTION__, tid); |
---|
[574] | 979 | #endif |
---|
| 980 | |
---|
[637] | 981 | sync_time[tid] += (unsigned int)(barrier_stop - barrier_start); |
---|
| 982 | sync_time[tid] += (long)(barrier_stop - barrier_start); |
---|
[469] | 983 | |
---|
| 984 | // copy tmp to x |
---|
| 985 | Copy( tmp , x , MyFirst , MyLast ); |
---|
| 986 | |
---|
| 987 | #if DEBUG_FFT1D |
---|
[637] | 988 | printf("\n[fft] %s : thread %d completed\n", __FUNCTION__, tid); |
---|
[574] | 989 | if( PRINT_ARRAY ) PrintArray( x , N ); |
---|
[469] | 990 | #endif |
---|
| 991 | |
---|
| 992 | } // end FFT1D() |
---|
| 993 | |
---|
| 994 | ///////////////////////////////////////////////////////////////////////////////////// |
---|
| 995 | // This function multiply all points contained in a row (rootN points) of the |
---|
| 996 | // x[] array by the corresponding twiddle factor, contained in the u[] array. |
---|
| 997 | ///////////////////////////////////////////////////////////////////////////////////// |
---|
[473] | 998 | void TwiddleOneCol( int direction, |
---|
| 999 | unsigned int j, // y coordinate in 2D view of coef array |
---|
| 1000 | double ** u, // coef array base address |
---|
| 1001 | double ** x, // data array base address |
---|
| 1002 | unsigned int offset_x ) // first point in N points data array |
---|
[469] | 1003 | { |
---|
[473] | 1004 | unsigned int i; |
---|
[469] | 1005 | double omega_r; |
---|
| 1006 | double omega_c; |
---|
| 1007 | double x_r; |
---|
| 1008 | double x_c; |
---|
[473] | 1009 | unsigned int c_id; |
---|
| 1010 | unsigned int c_offset; |
---|
[469] | 1011 | |
---|
| 1012 | for (i = 0; i < rootN ; i++) // loop on the rootN points |
---|
| 1013 | { |
---|
| 1014 | // get coef |
---|
| 1015 | c_id = (j * rootN + i) / (points_per_cluster); |
---|
| 1016 | c_offset = (j * rootN + i) % (points_per_cluster); |
---|
| 1017 | omega_r = u[c_id][2*c_offset]; |
---|
| 1018 | omega_c = direction * u[c_id][2*c_offset+1]; |
---|
| 1019 | |
---|
| 1020 | // access data |
---|
| 1021 | c_id = (offset_x + i) / (points_per_cluster); |
---|
| 1022 | c_offset = (offset_x + i) % (points_per_cluster); |
---|
| 1023 | x_r = x[c_id][2*c_offset]; |
---|
| 1024 | x_c = x[c_id][2*c_offset+1]; |
---|
| 1025 | |
---|
| 1026 | x[c_id][2*c_offset] = omega_r*x_r - omega_c * x_c; |
---|
| 1027 | x[c_id][2*c_offset+1] = omega_r*x_c + omega_c * x_r; |
---|
| 1028 | } |
---|
| 1029 | } // end TwiddleOneCol() |
---|
| 1030 | |
---|
[473] | 1031 | //////////////////////////// |
---|
| 1032 | void Scale( double ** x, // data array base address |
---|
| 1033 | unsigned int offset_x ) // first point of the row to be scaled |
---|
[469] | 1034 | { |
---|
[473] | 1035 | unsigned int i; |
---|
| 1036 | unsigned int c_id; |
---|
| 1037 | unsigned int c_offset; |
---|
[469] | 1038 | |
---|
| 1039 | for (i = 0; i < rootN ; i++) |
---|
| 1040 | { |
---|
| 1041 | c_id = (offset_x + i) / (points_per_cluster); |
---|
| 1042 | c_offset = (offset_x + i) % (points_per_cluster); |
---|
[473] | 1043 | x[c_id][2*c_offset] /= N; |
---|
| 1044 | x[c_id][2*c_offset + 1] /= N; |
---|
[469] | 1045 | } |
---|
| 1046 | } |
---|
| 1047 | |
---|
[473] | 1048 | /////////////////////////////////// |
---|
| 1049 | void Transpose( double ** src, // source buffer (array of pointers) |
---|
| 1050 | double ** dest, // destination buffer (array of pointers) |
---|
| 1051 | unsigned int MyFirst, // first row allocated to the thread |
---|
| 1052 | unsigned int MyLast ) // last row allocated to the thread |
---|
[469] | 1053 | { |
---|
[473] | 1054 | unsigned int row; // row index |
---|
| 1055 | unsigned int point; // data point index in a row |
---|
[469] | 1056 | |
---|
[473] | 1057 | unsigned int index_src; // absolute index in the source N points array |
---|
| 1058 | unsigned int c_id_src; // cluster for the source buffer |
---|
| 1059 | unsigned int c_offset_src; // offset in the source buffer |
---|
[469] | 1060 | |
---|
[473] | 1061 | unsigned int index_dst; // absolute index in the dest N points array |
---|
| 1062 | unsigned int c_id_dst; // cluster for the dest buffer |
---|
| 1063 | unsigned int c_offset_dst; // offset in the dest buffer |
---|
[469] | 1064 | |
---|
| 1065 | |
---|
| 1066 | // scan all data points allocated to the thread |
---|
| 1067 | // (between MyFirst row and MyLast row) from the source buffer |
---|
| 1068 | // and write these points to the destination buffer |
---|
| 1069 | for ( row = MyFirst ; row < MyLast ; row++ ) // loop on the rows |
---|
| 1070 | { |
---|
| 1071 | for ( point = 0 ; point < rootN ; point++ ) // loop on points in row |
---|
| 1072 | { |
---|
| 1073 | index_src = row * rootN + point; |
---|
| 1074 | c_id_src = index_src / (points_per_cluster); |
---|
| 1075 | c_offset_src = index_src % (points_per_cluster); |
---|
| 1076 | |
---|
| 1077 | index_dst = point * rootN + row; |
---|
| 1078 | c_id_dst = index_dst / (points_per_cluster); |
---|
| 1079 | c_offset_dst = index_dst % (points_per_cluster); |
---|
| 1080 | |
---|
| 1081 | dest[c_id_dst][2*c_offset_dst] = src[c_id_src][2*c_offset_src]; |
---|
| 1082 | dest[c_id_dst][2*c_offset_dst+1] = src[c_id_src][2*c_offset_src+1]; |
---|
| 1083 | } |
---|
| 1084 | } |
---|
| 1085 | } // end Transpose() |
---|
| 1086 | |
---|
[473] | 1087 | ////////////////////////////// |
---|
| 1088 | void Copy( double ** src, // source buffer (array of pointers) |
---|
| 1089 | double ** dest, // destination buffer (array of pointers) |
---|
| 1090 | unsigned int MyFirst, // first row allocated to the thread |
---|
| 1091 | unsigned int MyLast ) // last row allocated to the thread |
---|
[469] | 1092 | { |
---|
[473] | 1093 | unsigned int row; // row index |
---|
| 1094 | unsigned int point; // data point index in a row |
---|
[469] | 1095 | |
---|
[473] | 1096 | unsigned int index; // absolute index in the N points array |
---|
| 1097 | unsigned int c_id; // cluster index |
---|
| 1098 | unsigned int c_offset; // offset in local buffer |
---|
[469] | 1099 | |
---|
| 1100 | // scan all data points allocated to the thread |
---|
| 1101 | for ( row = MyFirst ; row < MyLast ; row++ ) // loop on the rows |
---|
| 1102 | { |
---|
| 1103 | for ( point = 0 ; point < rootN ; point++ ) // loop on points in row |
---|
| 1104 | { |
---|
| 1105 | index = row * rootN + point; |
---|
| 1106 | c_id = index / (points_per_cluster); |
---|
| 1107 | c_offset = index % (points_per_cluster); |
---|
| 1108 | |
---|
| 1109 | dest[c_id][2*c_offset] = src[c_id][2*c_offset]; |
---|
| 1110 | dest[c_id][2*c_offset+1] = src[c_id][2*c_offset+1]; |
---|
| 1111 | } |
---|
| 1112 | } |
---|
| 1113 | } // end Copy() |
---|
| 1114 | |
---|
[473] | 1115 | /////////////////////////////// |
---|
| 1116 | void Reverse( double ** x, |
---|
| 1117 | unsigned int offset_x ) |
---|
[469] | 1118 | { |
---|
[473] | 1119 | unsigned int j, k; |
---|
| 1120 | unsigned int c_id_j; |
---|
| 1121 | unsigned int c_offset_j; |
---|
| 1122 | unsigned int c_id_k; |
---|
| 1123 | unsigned int c_offset_k; |
---|
[469] | 1124 | |
---|
| 1125 | for (k = 0 ; k < rootN ; k++) |
---|
| 1126 | { |
---|
| 1127 | j = BitReverse( k ); |
---|
| 1128 | if (j > k) |
---|
| 1129 | { |
---|
| 1130 | c_id_j = (offset_x + j) / (points_per_cluster); |
---|
| 1131 | c_offset_j = (offset_x + j) % (points_per_cluster); |
---|
| 1132 | c_id_k = (offset_x + k) / (points_per_cluster); |
---|
| 1133 | c_offset_k = (offset_x + k) % (points_per_cluster); |
---|
| 1134 | |
---|
| 1135 | SWAP(x[c_id_j][2*c_offset_j] , x[c_id_k][2*c_offset_k]); |
---|
| 1136 | SWAP(x[c_id_j][2*c_offset_j+1], x[c_id_k][2*c_offset_k+1]); |
---|
| 1137 | } |
---|
| 1138 | } |
---|
| 1139 | } |
---|
| 1140 | |
---|
| 1141 | ///////////////////////////////////////////////////////////////////////////// |
---|
| 1142 | // This function makes the in-place FFT on all points contained in a row |
---|
| 1143 | // (i.e. rootN points) of the x[nclusters][points_per_cluster] array. |
---|
| 1144 | ///////////////////////////////////////////////////////////////////////////// |
---|
[574] | 1145 | void FFTRow( int direction, // 1 direct / -1 inverse |
---|
[473] | 1146 | double * u, // private coefs array |
---|
| 1147 | double ** x, // array of pointers on distributed buffers |
---|
| 1148 | unsigned int offset_x ) // absolute offset in the x array |
---|
[469] | 1149 | { |
---|
[473] | 1150 | unsigned int j; |
---|
| 1151 | unsigned int k; |
---|
| 1152 | unsigned int q; |
---|
| 1153 | unsigned int L; |
---|
| 1154 | unsigned int r; |
---|
| 1155 | unsigned int Lstar; |
---|
[469] | 1156 | double * u1; |
---|
| 1157 | |
---|
[473] | 1158 | unsigned int offset_x1; // index first butterfly input |
---|
| 1159 | unsigned int offset_x2; // index second butterfly output |
---|
[469] | 1160 | |
---|
[473] | 1161 | double omega_r; // real part butterfy coef |
---|
| 1162 | double omega_c; // complex part butterfly coef |
---|
[469] | 1163 | |
---|
[473] | 1164 | double tau_r; |
---|
| 1165 | double tau_c; |
---|
[469] | 1166 | |
---|
[473] | 1167 | double d1_r; // real part first butterfly input |
---|
| 1168 | double d1_c; // imag part first butterfly input |
---|
| 1169 | double d2_r; // real part second butterfly input |
---|
| 1170 | double d2_c; // imag part second butterfly input |
---|
[469] | 1171 | |
---|
[473] | 1172 | unsigned int c_id_1; // cluster index for first butterfly input |
---|
| 1173 | unsigned int c_offset_1; // offset for first butterfly input |
---|
| 1174 | unsigned int c_id_2; // cluster index for second butterfly input |
---|
| 1175 | unsigned int c_offset_2; // offset for second butterfly input |
---|
[469] | 1176 | |
---|
[574] | 1177 | #if DEBUG_ROW |
---|
[469] | 1178 | unsigned int p; |
---|
[628] | 1179 | printf("\n[fft] ROW data in / %d points / offset = %d\n", rootN , offset_x ); |
---|
[574] | 1180 | |
---|
[469] | 1181 | for ( p = 0 ; p < rootN ; p++ ) |
---|
| 1182 | { |
---|
[473] | 1183 | unsigned int index = offset_x + p; |
---|
| 1184 | unsigned int c_id = index / (points_per_cluster); |
---|
| 1185 | unsigned int c_offset = index % (points_per_cluster); |
---|
[469] | 1186 | printf("%f , %f | ", x[c_id][2*c_offset] , x[c_id][2*c_offset+1] ); |
---|
| 1187 | } |
---|
| 1188 | printf("\n"); |
---|
| 1189 | #endif |
---|
| 1190 | |
---|
| 1191 | // This makes the rootN input points reordering |
---|
| 1192 | Reverse( x , offset_x ); |
---|
| 1193 | |
---|
[574] | 1194 | #if DEBUG_ROW |
---|
[628] | 1195 | printf("\n[fft] ROW data after reverse / %d points / offset = %d\n", rootN , offset_x ); |
---|
[574] | 1196 | |
---|
[469] | 1197 | for ( p = 0 ; p < rootN ; p++ ) |
---|
| 1198 | { |
---|
[473] | 1199 | unsigned int index = offset_x + p; |
---|
| 1200 | unsigned int c_id = index / (points_per_cluster); |
---|
| 1201 | unsigned int c_offset = index % (points_per_cluster); |
---|
[469] | 1202 | printf("%f , %f | ", x[c_id][2*c_offset] , x[c_id][2*c_offset+1] ); |
---|
| 1203 | } |
---|
| 1204 | printf("\n"); |
---|
| 1205 | #endif |
---|
| 1206 | |
---|
| 1207 | // This implements the multi-stages, in place Butterfly network |
---|
| 1208 | for (q = 1; q <= M/2 ; q++) // loop on stages |
---|
| 1209 | { |
---|
| 1210 | L = 1 << q; // number of points per subset for current stage |
---|
| 1211 | r = rootN / L; // number of subsets |
---|
| 1212 | Lstar = L / 2; |
---|
| 1213 | u1 = &u[2 * (Lstar - 1)]; |
---|
| 1214 | for (k = 0; k < r; k++) // loop on the subsets |
---|
| 1215 | { |
---|
| 1216 | offset_x1 = offset_x + (k * L); // index first point |
---|
| 1217 | offset_x2 = offset_x + (k * L + Lstar); // index second point |
---|
| 1218 | |
---|
[574] | 1219 | #if (DEBUG_ROW & 1) |
---|
| 1220 | printf("\n ### q = %d / k = %d / x1 = %d / x2 = %d\n", q , k , offset_x1 , offset_x2 ); |
---|
[469] | 1221 | #endif |
---|
| 1222 | // makes all in-place butterfly(s) for subset |
---|
| 1223 | for (j = 0; j < Lstar; j++) |
---|
| 1224 | { |
---|
| 1225 | // get coef |
---|
| 1226 | omega_r = u1[2*j]; |
---|
| 1227 | omega_c = direction * u1[2*j+1]; |
---|
| 1228 | |
---|
| 1229 | // get d[x1] address and value |
---|
| 1230 | c_id_1 = (offset_x1 + j) / (points_per_cluster); |
---|
| 1231 | c_offset_1 = (offset_x1 + j) % (points_per_cluster); |
---|
| 1232 | d1_r = x[c_id_1][2*c_offset_1]; |
---|
| 1233 | d1_c = x[c_id_1][2*c_offset_1+1]; |
---|
| 1234 | |
---|
| 1235 | // get d[x2] address and value |
---|
| 1236 | c_id_2 = (offset_x2 + j) / (points_per_cluster); |
---|
| 1237 | c_offset_2 = (offset_x2 + j) % (points_per_cluster); |
---|
| 1238 | d2_r = x[c_id_2][2*c_offset_2]; |
---|
| 1239 | d2_c = x[c_id_2][2*c_offset_2+1]; |
---|
| 1240 | |
---|
[574] | 1241 | #if (DEBUG_ROW & 1) |
---|
[469] | 1242 | printf("\n ### d1_in = (%f , %f) / d2_in = (%f , %f) / coef = (%f , %f)\n", |
---|
| 1243 | d1_r , d1_c , d2_r , d2_c , omega_r , omega_c); |
---|
| 1244 | #endif |
---|
| 1245 | // tau = omega * d[x2] |
---|
| 1246 | tau_r = omega_r * d2_r - omega_c * d2_c; |
---|
| 1247 | tau_c = omega_r * d2_c + omega_c * d2_r; |
---|
| 1248 | |
---|
| 1249 | // set new value for d[x1] = d[x1] + omega * d[x2] |
---|
| 1250 | x[c_id_1][2*c_offset_1] = d1_r + tau_r; |
---|
| 1251 | x[c_id_1][2*c_offset_1+1] = d1_c + tau_c; |
---|
| 1252 | |
---|
| 1253 | // set new value for d[x2] = d[x1] - omega * d[x2] |
---|
| 1254 | x[c_id_2][2*c_offset_2] = d1_r - tau_r; |
---|
| 1255 | x[c_id_2][2*c_offset_2+1] = d1_c - tau_c; |
---|
| 1256 | |
---|
[574] | 1257 | #if (DEBUG_ROW & 1) |
---|
[469] | 1258 | printf("\n ### d1_out = (%f , %f) / d2_out = (%f , %f)\n", |
---|
| 1259 | d1_r + tau_r , d1_c + tau_c , d2_r - tau_r , d2_c - tau_c ); |
---|
| 1260 | #endif |
---|
| 1261 | } |
---|
| 1262 | } |
---|
| 1263 | } |
---|
| 1264 | |
---|
[574] | 1265 | #if DEBUG_ROW |
---|
[628] | 1266 | printf("\n[fft] ROW data out / %d points / offset = %d\n", rootN , offset_x ); |
---|
[469] | 1267 | for ( p = 0 ; p < rootN ; p++ ) |
---|
| 1268 | { |
---|
[473] | 1269 | unsigned int index = offset_x + p; |
---|
| 1270 | unsigned int c_id = index / (points_per_cluster); |
---|
| 1271 | unsigned int c_offset = index % (points_per_cluster); |
---|
[469] | 1272 | printf("%f , %f | ", x[c_id][2*c_offset] , x[c_id][2*c_offset+1] ); |
---|
| 1273 | } |
---|
| 1274 | printf("\n"); |
---|
| 1275 | #endif |
---|
| 1276 | |
---|
[574] | 1277 | } // end FFTRow() |
---|
[469] | 1278 | |
---|
[473] | 1279 | /////////////////////////////////////// |
---|
| 1280 | void PrintArray( double ** array, |
---|
| 1281 | unsigned int size ) |
---|
[469] | 1282 | { |
---|
[473] | 1283 | unsigned int i; |
---|
| 1284 | unsigned int c_id; |
---|
| 1285 | unsigned int c_offset; |
---|
[469] | 1286 | |
---|
| 1287 | // float display |
---|
| 1288 | for (i = 0; i < size ; i++) |
---|
| 1289 | { |
---|
| 1290 | c_id = i / (points_per_cluster); |
---|
| 1291 | c_offset = i % (points_per_cluster); |
---|
| 1292 | |
---|
| 1293 | printf(" %f %f |", array[c_id][2*c_offset], array[c_id][2*c_offset+1]); |
---|
| 1294 | |
---|
| 1295 | if ( (i+1) % 4 == 0) printf("\n"); |
---|
| 1296 | } |
---|
| 1297 | printf("\n"); |
---|
| 1298 | } |
---|
| 1299 | |
---|
| 1300 | |
---|
| 1301 | // Local Variables: |
---|
| 1302 | // tab-width: 4 |
---|
| 1303 | // c-basic-offset: 4 |
---|
| 1304 | // c-file-offsets:((innamespace . 0)(inline-open . 0)) |
---|
| 1305 | // indent-tabs-mode: nil |
---|
| 1306 | // End: |
---|
| 1307 | |
---|
| 1308 | // vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=4:softtabstop=4 |
---|
| 1309 | |
---|