Mark Rousskov a1d7367429 Move iter_results to dyn FnMut rather than a generic
This means that we're no longer generating the iteration/locking code for each
invocation site of iter_results, rather just once per query.

This is a 15% win in instruction counts when compiling the rustc_query_impl crate.
2021-04-29 17:26:46 -04:00
..
2021-04-12 13:58:12 +02:00

For more information about how the query system works, see the rustc dev guide.