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/* -------------------------------------------------------------------------- *
* Simbody(tm): SimTKcommon *
* -------------------------------------------------------------------------- *
* This is part of the SimTK biosimulation toolkit originating from *
* Simbios, the NIH National Center for Physics-Based Simulation of *
* Biological Structures at Stanford, funded under the NIH Roadmap for *
* Medical Research, grant U54 GM072970. See https://simtk.org/home/simbody. *
* *
* Portions copyright (c) 2008-17 Stanford University and the Authors. *
* Authors: Peter Eastman *
* Contributors: *
* *
* Licensed under the Apache License, Version 2.0 (the "License"); you may *
* not use this file except in compliance with the License. You may obtain a *
* copy of the License at http://www.apache.org/licenses/LICENSE-2.0. *
* *
* Unless required by applicable law or agreed to in writing, software *
* distributed under the License is distributed on an "AS IS" BASIS, *
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. *
* See the License for the specific language governing permissions and *
* limitations under the License. *
* -------------------------------------------------------------------------- */
// This test originally tested the SimTK::AtomicInteger class template. When
// SimTK::AtomicInteger was replaced with C++11 std::atomic, this test case
// was simplified. This test is now moreso a test of ParallelExecutor (rather
// than of operators for std::atomic).
#include "SimTKcommon.h"
#include <iostream>
#include <atomic>
#define ASSERT(cond) {SimTK_ASSERT_ALWAYS(cond, "Assertion failed");}
using std::cout;
using std::endl;
using namespace SimTK;
using namespace std;
void testParallelExecution() {
std::atomic<int> index;
vector<int> flags(10000);
for (int i = 0; i < (int)flags.size(); ++i)
flags[i] = 0;
ParallelExecutor executor;
// See if the ++ operator is properly atomic.
class SetFlagTask : public ParallelExecutor::Task {
public:
SetFlagTask(vector<int>& flags, std::atomic<int>& index) : flags(flags), index(index) {
}
void execute(int i) override {
flags[index++]++;
}
private:
vector<int>& flags;
std::atomic<int>& index;
};
for (int i = 0; i < 100; ++i) {
SetFlagTask task(flags, index);
index = 0;
executor.execute(task, 5000);
ASSERT(index == 5000);
for (int j = 0; j < (int)flags.size(); ++j)
ASSERT(flags[j] == (j < 5000 ? i+1 : 0));
}
// See if the += operator is properly atomic.
class IncrementTask : public ParallelExecutor::Task {
public:
IncrementTask(std::atomic<int>& index) : index(index) {
}
void execute(int i) override {
index += 2;
}
private:
std::atomic<int>& index;
};
for (int i = 0; i < 100; ++i) {
IncrementTask task(index);
index = 0;
executor.execute(task, 5000);
ASSERT(index == 10000);
}
}
int main() {
try {
testParallelExecution();
} catch(const std::exception& e) {
cout << "exception: " << e.what() << endl;
return 1;
}
cout << "Done" << endl;
return 0;
}
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