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#include <sys/time.h>
#include <iostream>
#include <sstream>
#include <vector>
#include <algorithm>
#include <assert.h>
#include <time.h>
#include <sched.h>
#include <math.h>
const long long US_PER_SECOND = 1000000L;
const long long NS_PER_US = 1000L;
using namespace std;
class Timer{
public:
Timer() {}
// note that CPU time is tracked per-thread, so the timer is only useful
// in the thread it was start()ed from.
void start() {
usec(start_time);
}
void lap(long long &us) {
usec(us);
us -= start_time;
}
long long lap() {
long long us;
usec(us);
return us - start_time;
}
void usec(long long &us) {
clock_gettime(clock, &ts);
us = ts.tv_sec * US_PER_SECOND + ts.tv_nsec / NS_PER_US;
}
/** Ask the OS nicely for a big time slice */
void ask_for_timeslice() {
sched_yield();
}
private:
long long start_time;
struct timespec ts;
#ifdef _POSIX_THREAD_CPUTIME
static const clockid_t clock = CLOCK_THREAD_CPUTIME_ID;
#else
# ifdef CLOCK_MONOTONIC
static const clockid_t clock = CLOCK_MONOTONIC;
# else
static const clockid_t clock = CLOCK_REALTIME;
# endif
#endif
};
int estimate_useful_window()
{
Timer tm;
tm.ask_for_timeslice();
int window = 1;
while(1) {
tm.start();
for(int i = 0; i < window; i++) {}
long long base_line = tm.lap();
if(base_line > 1 and window > 100)
return window;
window *= 2;
}
}
template <typename T>
string robust_timer(T &t) {
static int base_rate = estimate_useful_window();
//cout << "base line iterations:" << base_rate << endl;
double sum = 0;
vector<double> results;
const int n_trials = 20;
results.reserve(n_trials);
for(int trials = 0; trials < n_trials; trials++) {
Timer tm;
tm.ask_for_timeslice();
tm.start();
int iters = 0;
while(tm.lap() < 10000) {
for(int i = 0; i < base_rate; i++)
t();
iters+=base_rate;
}
base_rate = iters;
double lap_time = double(tm.lap());
double individual_time = lap_time/base_rate;
sum += individual_time;
results.push_back(individual_time);
//cout << individual_time << endl;
}
double resS = 0;
double resN = 0;
sort(results.begin(), results.end());
double ave = results[results.size()/2];//sum/n_trials; // median
//cout << "median:" << ave << endl;
double least = ave;
double resSS = 0;
for(int i = 0; i < n_trials; i++) {
double dt = results[i];
if(dt <= ave*1.1) {
resS += dt;
resN += 1;
resSS += dt*dt;
if(least < dt)
least = dt;
}
}
double filtered_ave = resS / resN;
double stddev = sqrt((resSS - 2*resS*filtered_ave + resN*filtered_ave*filtered_ave)/(resN-1)); // sum(x-u)^2 = sum(x^2-2xu+u*u)
assert (least > filtered_ave*0.7); // If this throws something was really screwy
std::basic_stringstream<char> ss;
ss << filtered_ave << " +/-" << stddev << "us";
return ss.str();
}
struct nop{
void operator()() const {}
};
#define degenerate_imported 1
#include "degenerate.cpp"
using namespace Geom;
template <typename T>
struct copy{
T a, b;
void operator()() {
T c = a;
}
};
template <typename T>
struct add{
T a, b;
void operator()() {
T c = a + b;
}
};
template <typename T>
struct add_mutate{
T a, b;
void operator()() {
a += b;
}
};
template <typename T>
struct scale{
T a;
double b;
void operator()() {
T c = a * b;
}
};
template <typename T>
struct scale_mutate{
T a;
double b;
void operator()() {
a *= b;
}
};
template <typename T>
struct mult{
T a, b;
void operator()() {
T c = a * b;
}
};
template <typename T>
struct mult_mutate{
T a, b, c;
void operator()() {
c = a;
c *= b;
}
};
template <typename T>
void basic_arith(T const & a, T const & b) {
{
::copy<T> A;
A.a = a;
A.b = b;
cout << "copy:"
<< robust_timer(A) << endl;
}
{
add<T> A;
A.a = a;
A.b = b;
cout << "add:"
<< robust_timer(A) << endl;
}
{
add_mutate<T> A;
A.a = a;
A.b = b;
cout << "add_mutate:"
<< robust_timer(A) << endl;
}
{
::scale<T> A;
A.a = a;
A.b = 1;
cout << "scale:"
<< robust_timer(A) << endl;
}
{
scale_mutate<T> A;
A.a = a;
A.b = 1;
cout << "scale_mutate:"
<< robust_timer(A) << endl;
}
{
mult<T> A;
A.a = a;
A.b = b;
cout << "mult:"
<< robust_timer(A) << endl;
}
{
mult_mutate<T> A;
A.a = a;
A.b = b;
cout << "mult_mutate:"
<< robust_timer(A) << endl;
}
}
#include <valarray>
#include <2geom/orphan-code/sbasisN.h>
#include <2geom/piecewise.h>
int main(int /*argc*/, char** /*argv*/) {
{
nop N;
cout << "nop:" << robust_timer(N) << endl;
}
vector<SBasis> sbs;
valarray<double> va(4), vb(4);
generate_random_sbasis(sbs);
cout << "double\n";
basic_arith(sbs[0][0][0], sbs[1][0][0]);
cout << "valarray\n";
basic_arith(va, vb);
//cout << "Linear\n";
//basic_arith(sbs[0][0], sbs[1][0]);
cout << "SBasis\n";
basic_arith(sbs[0], sbs[1]);
cout << "pw<SBasis>\n";
basic_arith(Piecewise<SBasis>(sbs[0]), Piecewise<SBasis>(sbs[1]));
/*cout << "SBasisN<1>\n";
SBasisN<1> sbnA = sbs[0];
SBasisN<1> sbnB = sbs[0];
basic_arith(sbnA, sbnB);*/
}
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