HackRF source benchmark

benchmark.cc

// Compile using $(CC) -Ofast -march=native benchmark.cc -o benchmark
#include <chrono>
#include <complex>
#include <iostream>
#include <vector>

using hc_t = std::chrono::high_resolution_clock;

int main(int argc, char *argv[]) {
    std::vector<std::complex<float>> _lut;
    std::vector<uint16_t> inBuf(100 * 256 * 1024);
    std::vector<std::complex<float>> outBuf(100 * 256 * 1024);

    for (size_t i = 0; i <= 0xffff; i++)
        _lut.push_back(std::complex<float>((i >> 8) * (1.f / 128.0f),
                                           (i & 0xff) * (1.f / 128.f)));
    for (auto &i : inBuf) i = rand();

    uint64_t ct1 = 0, ct2 = 0;

    while (1) {
        auto tp = hc_t::now();
        for (size_t i = 0; i < outBuf.size(); i++) outBuf[i] = _lut[inBuf[i]];
        auto t2 = hc_t::now() - tp;

        const int8_t *a = (int8_t *)(uint16_t *)(&inBuf[0]);
        tp = hc_t::now();  // reset ctr
        for (size_t i = 0; i < outBuf.size(); i++) {
            outBuf[i] =
                std::complex<float>(a[i * 2] / 128.f, a[i * 2 + 1] / 128.f);
        }
        auto t3 = hc_t::now() - tp;

        ct1 += t2.count();
        ct2 += t3.count();
        float ratio1 = float(t2.count()) / float(t3.count());
        float ratio2 = float(ct1) / float(ct2);
        std::cout << "Speedup: " << ratio1 << "(" << ratio2 << ")     \r";
        fflush(stdout);
    }
    return 0;
}