FFT_bench.c

#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <tgmath.h>
#include <time.h>
void printTime(clock_t start, clock_t end)
{
    printf("CPU time (sec): %f\n", (double) (end - start) / CLOCKS_PER_SEC);
}
#define FELD_PI 3.141592653589793
#define swap_ptr(a,b) do {void* TmP=a; a=b; b=TmP;} while (0)
int main()
{
    clock_t obj0;
    clock_t obj1;
    double _Complex _store2[65536];
    double _Complex *store2 = _store2;
    double _Complex _store3[65536];
    double _Complex *store3 = _store3;
    uint32_t r4;
    uint32_t v6;
    uint32_t v7;
    
    memset(store2, 0, 1048576);
    r4 = 16;
    
    double _Complex _a5[1 << (int32_t) r4 - 1];
    double _Complex *a5 = _a5;
    
    for (v6 = 0; v6 < 1 << (int32_t) r4 - 1; v6++) {
        a5[v6] = exp(I * (2.0 * FELD_PI * (double) v6 / (double) (1 <<
                                                                  (int32_t) r4)));
    }
    obj0 = clock();
    for (v7 = 0; v7 < 100; v7++) {
        uint32_t r8;
        int32_t v9;
        uint32_t r15;
        uint32_t v16;
        
        r8 = 65536;
        for (v9 = (int32_t) r4 - 1; v9 >= 0; v9--) {
            uint32_t v10;
            
            for (v10 = 0; v10 < 65536; v10++) {
                bool let11;
                double _Complex let12;
                double _Complex let13;
                double _Complex let14;
                
                let11 = (bool) (v10 & 1 << (int32_t) (uint32_t) v9);
                let12 = store2[v10 ^ 1 << (int32_t) (uint32_t) v9];
                let13 = store2[v10];
                let14 = let11 ? let12 - let13 : let13 + let12;
                store3[v10] = let11 ? a5[(v10 & ~(4294967295 <<
                                                  (int32_t) (uint32_t) v9)) <<
                                         (int32_t) r4 - 1 -
                                         (int32_t) (uint32_t) v9] *
                    let14 : let14;
            }
            swap_ptr(store2, store3);
            r8 = 65536;
        }
        r15 = r8;
        for (v16 = 1; v16 < r4; v16++) {
            uint32_t v17;
            
            for (v17 = 0; v17 < r15; v17++) {
                uint32_t let18;
                
                let18 = v17 >> 1;
                store3[v17] = store2[(let18 >> (int32_t) v16 << 1 | (v17 &
                                                                     1)) <<
                                     (int32_t) v16 | (let18 & ~(4294967295 <<
                                                                (int32_t) v16))];
            }
            swap_ptr(store2, store3);
            r15 = r15;
        }
    }
    obj1 = clock();
    printTime(obj0, obj1);
    return 0;
}