Method mergeUnits

src/memory/HeapAllocator.cpp:298–319

Merge two contiguous memory units that are not allocated. Memory unit 2 will be merged into memory unit 1 and memory unit 2 will be removed

// Merge two contiguous memory units that are not allocated.
/// Memory unit 2 will be merged into memory unit 1 and memory unit 2 will be removed
void HeapAllocator::mergeUnits(MemoryUnitHeader* unit1, MemoryUnitHeader* unit2) {

   assert(unit2->previousUnit == unit1);
   assert(unit1->nextUnit == unit2);
   assert(!unit1->isAllocated);
   assert(!unit2->isAllocated);
   assert(unit1->isNextContiguousMemory);

   unit1->size += unit2->size + sizeof(MemoryUnitHeader);
   unit1->nextUnit = unit2->nextUnit;
   assert(unit1->nextUnit != unit1);
   if (unit2->nextUnit != nullptr) {
       unit2->nextUnit->previousUnit = unit1;
   }
   unit1->isNextContiguousMemory = unit2->isNextContiguousMemory;

   // Destroy unit 2
   unit2->~MemoryUnitHeader();

   assert(unit1->previousUnit == nullptr || unit1->previousUnit->nextUnit == unit1);
   assert(unit1->nextUnit == nullptr || unit1->nextUnit->previousUnit == unit1);
}

// Reserve more memory for the allocator
void HeapAllocator::reserve(size_t sizeToAllocate) {