File indexing completed on 2024-10-13 13:23:09

 /*
     SPDX-FileCopyrightText: 2015-2017 Milian Wolff <mail@milianw.de>
 
     SPDX-License-Identifier: LGPL-2.1-or-later
 */
 
 #ifndef BENCH_POINTERS
 #define BENCH_POINTERS
 
 #include <algorithm>
 #include <cstdint>
 #include <iostream>
 #include <random>
 #include <vector>
 
 #include <malloc.h>
 
 #include "src/util/indices.h"
 
 template <typename Map>
 void benchPointers()
 {
     auto randGenerator = std::mt19937(0);
 
     uint32_t matches = 0;
     constexpr uint32_t NUM_POINTERS = 10000000;
     {
         std::vector<uint64_t> pointers(NUM_POINTERS);
         const auto baseline = mallinfo2().uordblks;
         std::cerr << "allocated vector:        \t" << baseline << std::endl;
         for (uint32_t i = 0; i < NUM_POINTERS; ++i) {
             pointers[i] = reinterpret_cast<uint64_t>(malloc(1));
         }
         const auto allocated = (mallinfo2().uordblks - baseline);
         std::cerr << "allocated input pointers:\t" << allocated << std::endl;
         for (auto ptr : pointers) {
             free(reinterpret_cast<void*>(ptr));
         }
         std::cerr << "freed input pointers:    \t" << (mallinfo2().uordblks - baseline) << std::endl;
         srand(0);
         std::shuffle(pointers.begin(), pointers.end(), randGenerator);
         malloc_trim(0);
         std::cerr << "begin actual benchmark:  \t" << (mallinfo2().uordblks - baseline) << std::endl;
 
         {
             Map map;
             for (auto ptr : pointers) {
                 AllocationInfoIndex index;
                 index.index = static_cast<uint32_t>(ptr);
                 map.addPointer(ptr, index);
             }
 
             const auto added = mallinfo2().uordblks - baseline;
             std::cerr << "pointers added:          \t" << added << " (" << (float(added) * 100.f / allocated)
                       << "% overhead)" << std::endl;
 
             std::shuffle(pointers.begin(), pointers.end(), randGenerator);
             for (auto ptr : pointers) {
                 AllocationInfoIndex index;
                 index.index = static_cast<uint32_t>(ptr);
                 auto allocation = map.takePointer(ptr);
                 if (allocation.second && allocation.first == index) {
                     ++matches;
                 }
             }
 
             std::cerr << "pointers removed:        \t" << mallinfo2().uordblks << std::endl;
             malloc_trim(0);
             std::cerr << "trimmed:                 \t" << mallinfo2().uordblks << std::endl;
         }
     }
     if (matches != NUM_POINTERS) {
         std::cerr << "FAILED!";
         abort();
     }
 }
 
 #endif