[convolvatron]

thats a strange statement. its certainly not black and white, but the compiler has explicit lifetime information, while the cache infrastructure is using heuristics. I worked on a project which supported region tags in the cache for compiler-directed allocation and it showed some decent gains (in simulation).

I guess this is one place where it seems possible to allow for compiler annotations without disabling the default heuristics so you could maybe get the best of both.