optimize to help compiler reduces accesses to simple arithmetic

[YashasSamaga]

Branch: develop

Currently, pawn::array_view duplicates the entire indirection table and stores it in std::vector for arrays with variable dimensions. The compiler does pretty good optimization for arrays whose size are already known but for obvious reasons, the compiler won't reduce the array views with dimension sizes which are obtained at runtime to arithmetic instructions. A hand-written code can clearly be much more efficient than pawn::array_view in such cases.

Solution 1:

Get rid of the container like features such as iterators, bounds checking, etc. in exchange for allowing the creation of optimizable temporaries in operator[]. This, of course, kills many of the features while performing as fast as hand written code.

Solution 2:

Ban the use of variable size dimensions and force users to provide a maximum size for the dimension size.

This solution is so bad that it shouldn't even be taken seriously.