In this case the value at the pointer is copied (though this is not necessarily the case as the optimiser may optimise it out).
int val = *pPtr;
In this case however no copy will take place:
int& rVal = *pPtr;
The reason no copy takes place is because a reference is not a machine code level construct. It is a higher level construct and thus is something the compiler uses internally rather than generating specific code for it.
The same, obviously, goes for function parameters.
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