diff options
author | Elijah Newren <newren@gmail.com> | 2020-11-05 00:22:40 +0000 |
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committer | Junio C Hamano <gitster@pobox.com> | 2020-11-04 17:09:49 -0800 |
commit | 6ccdfc2a206d8266ad7613999a0d3f6acdf44c89 (patch) | |
tree | bd38936b27b908a589f18c47cc28ceaa9d4c10f2 /strmap.h | |
parent | b70c82e6edd33aa03afecd52b0265cf1d9762e1b (diff) |
strmap: enable faster clearing and reusing of strmaps
When strmaps are used heavily, such as is done by my new merge-ort algorithm, and strmaps need to be cleared but then re-used (because of e.g. picking multiple commits to cherry-pick, or due to a recursive merge having several different merges while recursing), free-ing and reallocating map->table repeatedly can add up in time, especially since it will likely be reallocated to a much smaller size but the previous merge provides a good guide to the right size to use for the next merge. Introduce strmap_partial_clear() to take advantage of this type of situation; it will act similar to strmap_clear() except that map->table's entries are zeroed instead of map->table being free'd. Making use of this function reduced the cost of clear_or_reinit_internal_opts() by about 20% in mert-ort, and dropped the overall runtime of my rebase testcase by just under 2%. Signed-off-by: Elijah Newren <newren@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Diffstat (limited to 'strmap.h')
-rw-r--r-- | strmap.h | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/strmap.h b/strmap.h index f74bc582e4..c14fcee148 100644 --- a/strmap.h +++ b/strmap.h @@ -43,6 +43,12 @@ void strmap_init_with_options(struct strmap *map, void strmap_clear(struct strmap *map, int free_values); /* + * Similar to strmap_clear() but leaves map->map->table allocated and + * pre-sized so that subsequent uses won't need as many rehashings. + */ +void strmap_partial_clear(struct strmap *map, int free_values); + +/* * Insert "str" into the map, pointing to "data". * * If an entry for "str" already exists, its data pointer is overwritten, and |