Vector: Reserve, Allocate in 32 byte chunks

This commit is contained in:
2019-05-08 21:00:10 +02:00
parent fdb376f360
commit 619fb4e2b5

View File

@@ -7,28 +7,65 @@ class Vector
{ {
private: private:
T * data; T * data;
std::size_t byteSize;
std::size_t reserveSize;
std::size_t size; std::size_t size;
public: void Allocate(std::size_t const allocationSize)
void Resize(std::size_t const newSize)
{ {
if(newSize == 0ul) if(allocationSize == 0ul)
{ {
std::free(data); std::free(data);
data = nullptr; data = nullptr;
byteSize = 0ul;
reserveSize = 0ul;
return; return;
} }
void * result = std::realloc(data, newSize * sizeof(T)); std::size_t newByteSize = allocationSize * sizeof(T);
newByteSize += newByteSize % 32ul; // Allocate in blocks of 32 bytes
if(newByteSize <= byteSize)
{
reserveSize = allocationSize;
return;
}
void * result = std::realloc(data, newByteSize);
if(result == nullptr) if(result == nullptr)
{ {
throw std::runtime_error("Cannot allocate the requested size of memory."); throw std::runtime_error("Cannot allocate the requested size of memory.");
} }
size = newSize; byteSize = newByteSize;
reserveSize = allocationSize;
data = reinterpret_cast<T *>(result); data = reinterpret_cast<T *>(result);
} }
public:
void Resize(std::size_t const newSize)
{
if (newSize > reserveSize)
{
Allocate(newSize);
size = newSize;
return;
}
size = newSize;
}
void Reserve(std::size_t const newReserveSize)
{
if(newReserveSize < size)
{
Allocate(size);
return;
}
Allocate(newReserveSize);
}
T & operator[](std::size_t const index) T & operator[](std::size_t const index)
{ {
if(index >= size) if(index >= size)
@@ -45,6 +82,8 @@ public:
Vector() Vector()
: data(nullptr), : data(nullptr),
size(0U) byteSize(0ul),
reserveSize(0ul),
size(0ul)
{} {}
}; };