SuperWord::unrolling_analysis() question

[Roland Westrelin]

Hi Michael,

Thanks for the answer.

> The answer could be conditional if we had a machines with enough byte
> or short components to make vectors with, I chose INT as it is the
> current consistent minimum configuration for complete vector mapping.
> The best answer would be to create some code which mines the common
> type used in the current loops expressions, but I think we would be
> stuck with two passes over the code, the first to bind the common
> type, the second for finding the optimal sub vector mapping.  Or
> possibly moving the question to the machine layer as a query, where
> compiler writers choose the minimum consistent configuration based on
> current info on the machine we compile on.

Would two passes like sketched here:

http://cr.openjdk.java.net/~roland/vect-unroll-analysis/webrev/

would do the job?

Roland.