diff --git a/test/libm-bench.cpp b/test/libm-bench.cpp new file mode 100644 index 0000000..5b9e139 --- /dev/null +++ b/test/libm-bench.cpp @@ -0,0 +1,142 @@ +// Benchmark on libm functions + +#include +#include +#include +#include + + +// Timing facilities + +#ifdef __MACH__ + +#include + +class stimer +{ +public: + typedef uint64_t time_type; + + stimer() + { + ::mach_timebase_info(&m_baseinfo); + } + + time_type current() const + { + return ::mach_absolute_time(); + } + + double span(const time_type& t0, const time_type& t1) const + { + uint64_t d = (m_baseinfo.numer * (t1 - t0)) / m_baseinfo.denom; + return static_cast(d) / 1.0e9; + } + +private: + mach_timebase_info_data_t m_baseinfo; +}; + +#else + +class stimer +{ +public: + typedef timespec time_type; + + time_type current() const + { + time_type t; + ::clock_gettime(CLOCK_REALTIME, &t); + return t; + } + + double span(const time_type& t0, const time_type& t1) const + { + return double(t1.tv_sec - t0.tv_sec) + + double(t1.tv_nsec - t0.tv_nsec) * 1.0e-9; + } +}; + +#endif + + +inline double sec2mps(double s, long n) +{ + return n / (s * 1e6); +} + + +const long ARR_LEN = 1024; + +double a[ARR_LEN]; +double b[ARR_LEN]; +double r[ARR_LEN]; + +#define TFUN1(FNAME) \ + void test_##FNAME(long n) { \ + for (int j = 0; j < ARR_LEN; ++j) r[j] = FNAME(a[j]); \ + stimer tm; \ + stimer::time_type t0 = tm.current(); \ + for(int i = 0; i < n; ++i) { \ + for (int j = 0; j < ARR_LEN; ++j) r[j] = FNAME(a[j]); \ + } \ + double s = tm.span(t0, tm.current()); \ + double mps = sec2mps(s, n * ARR_LEN); \ + printf(" %-8s: %7.4f MPS\n", #FNAME, mps); } + +#define TFUN2(FNAME) \ + void test_##FNAME(long n) { \ + for (int j = 0; j < ARR_LEN; ++j) r[j] = FNAME(a[j], b[j]); \ + stimer tm; \ + stimer::time_type t0 = tm.current(); \ + for(int i = 0; i < n; ++i) { \ + for (int j = 0; j < ARR_LEN; ++j) r[j] = FNAME(a[j], b[j]); \ + } \ + double s = tm.span(t0, tm.current()); \ + double mps = sec2mps(s, n * ARR_LEN); \ + printf(" %-8s: %7.4f MPS\n", #FNAME, mps); } + + +#define TCALL(FNAME) test_##FNAME(20000) + +// define benchmark functions + +TFUN2(pow) +TFUN2(hypot) + +TFUN1(exp) +TFUN1(log) +TFUN1(log10) +TFUN1(sin) +TFUN1(cos) +TFUN1(tan) +TFUN1(asin) +TFUN1(acos) +TFUN1(atan) +TFUN2(atan2) + +int main(int argc, char *argv[]) +{ + // initialize array contents + for (int i = 0; i < ARR_LEN; ++i) + { + a[i] = rand() / (double) RAND_MAX; + b[i] = rand() / (double) RAND_MAX; + } + + TCALL(pow); + TCALL(hypot); + TCALL(exp); + TCALL(log); + TCALL(log10); + TCALL(sin); + TCALL(cos); + TCALL(tan); + TCALL(asin); + TCALL(acos); + TCALL(atan); + TCALL(atan2); + + return 0; +}