It means that the compiler knows that pointers/arrays don't overlap in memory. Data can therefore be safely stored in registers, instead of continually re-read

It means that the compiler knows that pointers/arrays don't overlap in memory. Data can therefore be safely stored in registers, instead of continually re-read from memory, to account for possible alterations between computations [1]. [1]: http://stackoverflow.com/questions/146159/is-fortran-faster-than-c#146186 http://stackoverflow.com/questions/146159/is-fortran-faster-...