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#include <algorithm>
#include <functional>
#include <iostream>
#include <chrono>
#include <deque>
#include <vector>
#include <cstring>
#include <cstdlib>
#include "libdivide.h"
#if defined(__GNUC__)
#define NOINLINE __attribute__((__noinline__))
#else
#define NOINLINE
#endif
template<typename T, int ALGO>
struct prime_divider_t {
T value;
libdivide::divider<T, ALGO> divider;
prime_divider_t(T v) : value(v), divider(v) {}
};
template<typename T, int ALGO> NOINLINE
size_t count_primes_libdivide(T max)
{
std::vector<prime_divider_t<T, ALGO> > primes;
primes.push_back(2);
for (T i=3; i < max; i+=2) {
bool is_prime = true;
for (const auto &prime : primes) {
T quotient = i / prime.divider;
T remainder = i - quotient * prime.value;
if (remainder == 0) {
is_prime = false;
break;
}
}
if (is_prime) {
primes.push_back(i);
}
}
return primes.size();
}
template<typename T> NOINLINE
size_t count_primes_system(T max)
{
std::vector<T> primes;
primes.push_back(2);
for (T i=3; i < max; i+=2) {
bool is_prime = true;
for (const auto &prime : primes) {
if (i % prime == 0) {
is_prime = false;
break;
}
}
if (is_prime) {
primes.push_back(i);
}
}
return primes.size();
}
template<typename Ret, typename... Args>
std::pair<double, Ret> time_function(std::function<Ret(Args...)> func, Args... args) {
using namespace std::chrono;
high_resolution_clock::time_point t1 = high_resolution_clock::now();
size_t result = func(args...);
high_resolution_clock::time_point t2 = high_resolution_clock::now();
duration<double> time_span = duration_cast<duration<double>>(t2 - t1);
return std::make_pair(time_span.count(), result);
}
struct prime_calculation_result_t {
double duration;
size_t result;
};
template<typename T, size_t Func(T)>
prime_calculation_result_t measure_1_prime_calculation(T max, size_t iters) {
double best = std::numeric_limits<double>::max();
size_t result = -1;
while (iters--) {
double time;
std::tie(time, result) = time_function(std::function<size_t(T)>(Func), max);
best = std::min(time, best);
}
return {best, result};
}
enum {
TEST_U32 = 1 << 0,
TEST_U64 = 1 << 1,
TEST_S32 = 1 << 2,
TEST_S64 = 1 << 3,
TEST_ALL_TYPES = (TEST_U32 | TEST_U64 | TEST_S32 | TEST_S64),
TEST_SYSTEM = 1 << 4,
TEST_BRANCHFREE = 1 << 5,
TEST_BRANCHFULL = 1 << 6,
TEST_ALL_ALGOS = (TEST_SYSTEM | TEST_BRANCHFREE | TEST_BRANCHFULL),
};
typedef unsigned int tasks_t;
template<typename T>
void measure_times(tasks_t tasks, T max, size_t iters) {
bool test_system = !! (tasks & TEST_SYSTEM);
bool test_branchfull = !! (tasks & TEST_BRANCHFULL);
bool test_branchfree = !! (tasks & TEST_BRANCHFREE);
prime_calculation_result_t sys = {0, 0};
prime_calculation_result_t branchfull = {0, 0};
prime_calculation_result_t branchfree = {0, 0};
if (test_system) {
sys = measure_1_prime_calculation<T, count_primes_system<T>>(max, iters);
std::cout << '.' << std::flush;
}
if (test_branchfull) {
branchfull = measure_1_prime_calculation<T, count_primes_libdivide<T, libdivide::BRANCHFULL>>(max, iters);
std::cout << '.' << std::flush;
}
if (test_branchfree) {
branchfree = measure_1_prime_calculation<T, count_primes_libdivide<T, libdivide::BRANCHFREE>>(max, iters);
std::cout << '.' << std::endl;
}
if (test_system && test_branchfull && branchfull.result != sys.result) {
std::cerr << "Disagreement in branchfull path for type " << typeid(T).name() << ": libdivide says " << branchfull.result << " but system says " << sys.result << std::endl;
std::exit(1);
}
if (test_system && test_branchfree && branchfree.result != sys.result) {
std::cerr << "Disagreement in branchfree path for type " << typeid(T).name() << ": libdivide says " << branchfree.result << " but system says " << sys.result << std::endl;
std::exit(1);
}
if (test_system) std::cout << "\t system: " << sys.duration << " seconds" << std::endl;
if (test_branchfull) std::cout << "\tbranchfull: " << branchfull.duration << " seconds" << std::endl;
if (test_branchfree) std::cout << "\tbranchfree: " << branchfree.duration << " seconds" << std::endl;
}
static void usage() {
std::cout << "Usage: primes [u32] [u64] [s32] [s64] [branchfree] [branchfull] [sys|system]" << std::endl;
}
int main(int argc, const char *argv[]) {
tasks_t tasks = 0;
// parse argv
for (int i = 1; i < argc; i++) {
const char * arg = argv[i];
if (! strcmp(arg, "u32")) {
tasks |= TEST_U32;
} else if (! strcmp(arg, "u64")) {
tasks |= TEST_U64;
} else if (! strcmp(arg, "s32")) {
tasks |= TEST_S32;
} else if (! strcmp(arg, "s64")) {
tasks |= TEST_S64;
} else if (! strcmp(arg, "branchfree")) {
tasks |= TEST_BRANCHFREE;
} else if (! strcmp(arg, "branchfull")) {
tasks |= TEST_BRANCHFULL;
} else if (! strcmp(arg, "sys") || ! strcmp(arg, "system")) {
tasks |= TEST_SYSTEM;
} else {
std::cout << "Unknown argument '" << arg << "'" << std::endl;
usage();
return -1;
}
}
// Set default tasks
if (! (tasks & TEST_ALL_TYPES)) {
tasks |= TEST_ALL_TYPES;
}
if (! (tasks & TEST_ALL_ALGOS)) {
tasks |= TEST_ALL_ALGOS;
}
size_t iters = 64;// * 100000;
if (tasks & TEST_U32) {
std::cout << "----- u32 -----" << std::endl;
measure_times<uint32_t>(tasks, 40000, iters);
}
if (tasks & TEST_U64) {
std::cout << "----- u64 -----" << std::endl;
measure_times<uint64_t>(tasks, 40000, iters);
}
if (tasks & TEST_S32) {
std::cout << "----- s32 -----" << std::endl;
measure_times<int32_t>(tasks, 40000, iters);
}
if (tasks & TEST_S64) {
std::cout << "----- s64 -----" << std::endl;
measure_times<int64_t>(tasks, 40000, iters);
}
return 0;
}
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