comparison rust/hg-core/src/dagops.rs @ 41717:9060af281be7

rust: itering less on MissingAncestors.bases for max()

Instead of iterating on the whole `self.bases` each time to find
its max, we keep the latter in a separate member attribute and
keep it up to date in `add_bases()`

On a perfdiscovery done on PyPy, with repos prepared with
`contrib/discovery-helper.sh 50 100`, this gives a slight
improvement (around 0.5% on wall time, but 10% on CPU)

before:
! wall 0.172801 comb 0.180000 user 0.180000 sys 0.000000 (median of 541)
after:
! wall 0.171798 comb 0.160000 user 0.160000 sys 0.000000 (median of 551)

(perf command run time upped because of bigger variability during this test).

Differential Revision: https://phab.mercurial-scm.org/D5945

41716:977432970080

    iter_revs: impl Clone + Iterator<Item = &'a Revision>,
) -> Result<HashSet<Revision>, GraphError> {
    let mut heads: HashSet<Revision> = iter_revs.clone().cloned().collect();
    heads.remove(&NULL_REVISION);
    for rev in iter_revs {
        remove_parents(graph, *rev, &mut heads)?;
    }
    Ok(heads)
}

/// Retain in `revs` only its relative heads.

    revs.remove(&NULL_REVISION);
    // we need to construct an iterable copy of revs to avoid itering while
    // mutating
    let as_vec: Vec<Revision> = revs.iter().cloned().collect();
    for rev in as_vec {
        remove_parents(graph, rev, revs)?;
    }
    Ok(())
}

#[cfg(test)]

41717:9060af281be7

    iter_revs: impl Clone + Iterator<Item = &'a Revision>,
) -> Result<HashSet<Revision>, GraphError> {
    let mut heads: HashSet<Revision> = iter_revs.clone().cloned().collect();
    heads.remove(&NULL_REVISION);
    for rev in iter_revs {
        if *rev != NULL_REVISION {
            remove_parents(graph, *rev, &mut heads)?;
        }
    }
    Ok(heads)
}

/// Retain in `revs` only its relative heads.

    revs.remove(&NULL_REVISION);
    // we need to construct an iterable copy of revs to avoid itering while
    // mutating
    let as_vec: Vec<Revision> = revs.iter().cloned().collect();
    for rev in as_vec {
        if rev != NULL_REVISION {
            remove_parents(graph, rev, revs)?;
        }
    }
    Ok(())
}

#[cfg(test)]