Make List.map_filter(_i) tail-recursive.

While the performance gain should go unnoticed in most cases, in some
degenerate situations, e.g. the evar-stressing test-case of bug #4964,
this commit speeds up coq by 10% since most of the time is spent scanning
long lists with most of the elements filtered out.

Note that this commit also changes the scanning order to front-to-back,
which is a bit less surprising (though no code should ever depend on the
scanning order).

0 files changed, 0 insertions, 0 deletions