dirstate: add a C implementation for nonnormalentries
Before this patch, there was only a python version of nonnormalentries.
On mozilla-central we have a 10x win by putting this function in C:
% python -m timeit -s \
'from mercurial import hg, ui, parsers; \
repo = hg.repository(ui.ui(), "mozilla-central"); \
m = repo.dirstate._map' \
'parsers.nonnormalentries(m)'
100 loops, best of 3: 3.15 msec per loop
The python implementation runs in 31ms, a similar test gives:
10 loops, best of 3: 31.7 msec per loop
On our big repos, the win is still of 10x with the python implementation running
in 350ms and the C implementation running in 30ms.
$ hg init a
$ cd a
$ echo a > a
$ hg ci -Am0
adding a
$ echo b > b
$ hg ci -Am1
adding b
$ hg tag -r0 default
warning: tag default conflicts with existing branch name
$ hg log
changeset: 2:30a83d1e4a1e
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Added tag default for changeset f7b1eb17ad24
changeset: 1:925d80f479bb
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 1
changeset: 0:f7b1eb17ad24
tag: default
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 0
$ hg update 'tag(default)'
0 files updated, 0 files merged, 2 files removed, 0 files unresolved
$ hg parents
changeset: 0:f7b1eb17ad24
tag: default
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: 0
$ hg update 'branch(default)'
2 files updated, 0 files merged, 0 files removed, 0 files unresolved
$ hg parents
changeset: 2:30a83d1e4a1e
tag: tip
user: test
date: Thu Jan 01 00:00:00 1970 +0000
summary: Added tag default for changeset f7b1eb17ad24
$ cd ..