[_chris_]

The wonderful thing about caches is that they are invisible to the programmer; the designer can add bigger caches, more levels of caches, different configurations of shared/private/inclusive/exclusive caches... and it Just Works.

However, there are many machines, which instead of using caches, use programmer-visible “scratchpads”. There are many reasons for this, but two big reasons are performance-predictability (real-time systems) or to avoid the hw complexity of cache management.

In general though, scratchpads are hugely painful to program for and terrible for code portability.