Moved 'garbage collector' to sp_collector.cpp, collector_test.cpp added.

[SVN r17050]

test/collector_test.cpp

@@ -0,0 +1,100 @@
+//
+//  collector_test.cpp
+//
+//  Copyright (c) 2003 Peter Dimov
+//
+//  Permission to copy, use, modify, sell and distribute this software
+//  is granted provided this copyright notice appears in all copies.
+//  This software is provided "as is" without express or implied
+//  warranty, and with no claim as to its suitability for any purpose.
+//
+
+#include <boost/shared_ptr.hpp>
+#include <vector>
+#include <iostream>
+#include <cstdlib>
+#include <ctime>
+
+// sp_collector.cpp exported functions
+
+std::size_t find_unreachable_objects(bool report);
+void free_unreachable_objects();
+
+struct X
+{
+    void* fill[32];
+    boost::shared_ptr<X> p;
+};
+
+void report()
+{
+    std::cout << "Calling find_unreachable_objects:\n";
+
+    std::clock_t t = std::clock();
+
+    std::size_t n = find_unreachable_objects(false);
+
+    t = std::clock() - t;
+
+    std::cout << n << " unreachable objects.\n";
+    std::cout << "  " << static_cast<double>(t) / CLOCKS_PER_SEC << " seconds.\n";
+}
+
+void free()
+{
+    std::cout << "Calling free_unreachable_objects:\n";
+
+    std::clock_t t = std::clock();
+
+    free_unreachable_objects();
+
+    t = std::clock() - t;
+
+    std::cout << "  " << static_cast<double>(t) / CLOCKS_PER_SEC << " seconds.\n";
+}
+
+int main()
+{
+    std::vector< boost::shared_ptr<X> > v1, v2;
+
+    int const n = 256 * 1024;
+
+    std::cout << "Filling v1 and v2\n";
+
+    for(int i = 0; i < n; ++i)
+    {
+        v1.push_back(boost::shared_ptr<X>(new X));
+        v2.push_back(boost::shared_ptr<X>(new X));
+    }
+
+    report();
+
+    std::cout << "Creating the cycles\n";
+
+    for(int i = 0; i < n - 1; ++i)
+    {
+        v2[i]->p = v2[i+1];
+    }
+
+    v2[n-1]->p = v2[0];
+
+    report();
+
+    std::cout << "Resizing v2 to size of 1\n";
+
+    v2.resize(1);
+    report();
+
+    std::cout << "Clearing v2\n";
+
+    v2.clear();
+    report();
+
+    std::cout << "Clearing v1\n";
+
+    v1.clear();
+    report();
+
+    free();
+    report();
+}