Are references or pointers faster?

Question

From what I know, references are just another name for a variable whilst pointers are their own variable. Pointers take up space. People often say "use a reference or pointer" but they don't say which is better. If references take up no memory of their own, then references win in that department. What I don't know is if the compiler makes a distinction between references and normal variable. If you do operations on a reference, does it compile to the same code as normal variable?

Answer 1

Internally references are also implemented in terms of pointer. So, it's difficult to say which is faster pointer/reference.

It's a usage of these two which makes a difference.

For example you want to pass by reference a parameter to the function.

void func(int& a)    case_1
{
  //No need to check for NULL reference...
}
void func(int* a)    case_2
{
  //Need o check if pointer is not NULL
}

In case_2 you have to explicitly check if pointer is not NULL before dereferncing it whereas that's not the case with references because references are initialized to something.

Assumption is that you are playing game in civilized manner i.e

You are not doing something like:-

int*p = NULL;
int &a = *p;