From: Elijah Newren <newren@xxxxxxxxx>
Compute dir_rename_counts based just on exact renames to start, as that
can provide us useful information in find_basename_matches(). This is
done by moving the code from compute_dir_rename_counts() into
initialize_dir_rename_info(), resulting in it being computed earlier and
based just on exact renames. Since that's an incomplete result, we
augment the counts via calling update_dir_rename_counts() after each
basename-guide and inexact rename detection match is found.
Signed-off-by: Elijah Newren <newren@xxxxxxxxx>
---
diffcore-rename.c | 110 +++++++++++++++++++++++++++++-----------------
1 file changed, 70 insertions(+), 40 deletions(-)
diff --git a/diffcore-rename.c b/diffcore-rename.c
index 2cf9c47c6364..10f8f4a301e3 100644
--- a/diffcore-rename.c
+++ b/diffcore-rename.c
@@ -419,6 +419,28 @@ static void update_dir_rename_counts(struct dir_rename_info *info,
char new_dir_first_char = new_dir[0];
int first_time_in_loop = 1;
+ if (!info->setup)
+ /*
+ * info->setup is 0 here in two cases: (1) all auxiliary
+ * vars (like dirs_removed) were NULL so
+ * initialize_dir_rename_info() returned early, or (2)
+ * either break detection or copy detection are active so
+ * that we never called initialize_dir_rename_info(). In
+ * the former case, we don't have enough info to know if
+ * directories were renamed (because dirs_removed lets us
+ * know about a necessary prerequisite, namely if they were
+ * removed), and in the latter, we don't care about
+ * directory renames or find_basename_matches.
+ *
+ * This matters because both basename and inexact matching
+ * will also call update_dir_rename_counts(). In either of
+ * the above two cases info->dir_rename_counts will not
+ * have been properly initialized which prevents us from
+ * updating it, but in these two cases we don't care about
+ * dir_rename_counts anyway, so we can just exit early.
+ */
+ return;
+
while (1) {
dirname_munge(old_dir);
dirname_munge(new_dir);
@@ -479,45 +501,29 @@ static void update_dir_rename_counts(struct dir_rename_info *info,
free(new_dir);
}
-static void compute_dir_rename_counts(struct dir_rename_info *info,
- struct strset *dirs_removed,
- struct strmap *dir_rename_count)
+static void initialize_dir_rename_info(struct dir_rename_info *info,
+ struct strset *dirs_removed,
+ struct strmap *dir_rename_count)
{
int i;
- info->setup = 1;
- info->dir_rename_count = dir_rename_count;
-
- for (i = 0; i < rename_dst_nr; ++i) {
- /* File not part of directory rename counts if not a rename */
- if (!rename_dst[i].is_rename)
- continue;
-
- /*
- * Make dir_rename_count contain a map of a map:
- * old_directory -> {new_directory -> count}
- * In other words, for every pair look at the directories for
- * the old filename and the new filename and count how many
- * times that pairing occurs.
- */
- update_dir_rename_counts(info, dirs_removed,
- rename_dst[i].p->one->path,
- rename_dst[i].p->two->path);
+ if (!dirs_removed) {
+ info->setup = 0;
+ return;
}
-}
-
-static void initialize_dir_rename_info(struct dir_rename_info *info)
-{
- int i;
-
info->setup = 1;
+ info->dir_rename_count = dir_rename_count;
+ if (!info->dir_rename_count) {
+ info->dir_rename_count = xmalloc(sizeof(*dir_rename_count));
+ strmap_init(info->dir_rename_count);
+ }
strintmap_init_with_options(&info->idx_map, -1, NULL, 0);
strmap_init_with_options(&info->dir_rename_guess, NULL, 0);
- info->dir_rename_count = NULL;
/*
- * Loop setting up both info->idx_map.
+ * Loop setting up both info->idx_map, and doing setup of
+ * info->dir_rename_count.
*/
for (i = 0; i < rename_dst_nr; ++i) {
/*
@@ -527,7 +533,20 @@ static void initialize_dir_rename_info(struct dir_rename_info *info)
if (!rename_dst[i].is_rename) {
char *filename = rename_dst[i].p->two->path;
strintmap_set(&info->idx_map, filename, i);
+ continue;
}
+
+ /*
+ * For everything else (i.e. renamed files), make
+ * dir_rename_count contain a map of a map:
+ * old_directory -> {new_directory -> count}
+ * In other words, for every pair look at the directories for
+ * the old filename and the new filename and count how many
+ * times that pairing occurs.
+ */
+ update_dir_rename_counts(info, dirs_removed,
+ rename_dst[i].p->one->path,
+ rename_dst[i].p->two->path);
}
}
@@ -682,7 +701,8 @@ static int idx_possible_rename(char *filename, struct dir_rename_info *info)
static int find_basename_matches(struct diff_options *options,
int minimum_score,
- struct dir_rename_info *info)
+ struct dir_rename_info *info,
+ struct strset *dirs_removed)
{
/*
* When I checked in early 2020, over 76% of file renames in linux
@@ -810,6 +830,8 @@ static int find_basename_matches(struct diff_options *options,
continue;
record_rename_pair(dst_index, src_index, score);
renames++;
+ update_dir_rename_counts(info, dirs_removed,
+ one->path, two->path);
/*
* Found a rename so don't need text anymore; if we
@@ -893,7 +915,12 @@ static int too_many_rename_candidates(int num_destinations, int num_sources,
return 1;
}
-static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, int copies)
+static int find_renames(struct diff_score *mx,
+ int dst_cnt,
+ int minimum_score,
+ int copies,
+ struct dir_rename_info *info,
+ struct strset *dirs_removed)
{
int count = 0, i;
@@ -910,6 +937,9 @@ static int find_renames(struct diff_score *mx, int dst_cnt, int minimum_score, i
continue;
record_rename_pair(mx[i].dst, mx[i].src, mx[i].score);
count++;
+ update_dir_rename_counts(info, dirs_removed,
+ rename_src[mx[i].src].p->one->path,
+ rename_dst[mx[i].dst].p->two->path);
}
return count;
}
@@ -981,6 +1011,8 @@ void diffcore_rename_extended(struct diff_options *options,
info.setup = 0;
assert(!dir_rename_count || strmap_empty(dir_rename_count));
want_copies = (detect_rename == DIFF_DETECT_COPY);
+ if (dirs_removed && (break_idx || want_copies))
+ BUG("dirs_removed incompatible with break/copy detection");
if (!minimum_score)
minimum_score = DEFAULT_RENAME_SCORE;
@@ -1074,14 +1106,15 @@ void diffcore_rename_extended(struct diff_options *options,
/* Preparation for basename-driven matching. */
trace2_region_enter("diff", "dir rename setup", options->repo);
- initialize_dir_rename_info(&info);
+ initialize_dir_rename_info(&info,
+ dirs_removed, dir_rename_count);
trace2_region_leave("diff", "dir rename setup", options->repo);
/* Utilize file basenames to quickly find renames. */
trace2_region_enter("diff", "basename matches", options->repo);
rename_count += find_basename_matches(options,
min_basename_score,
- &info);
+ &info, dirs_removed);
trace2_region_leave("diff", "basename matches", options->repo);
/*
@@ -1167,18 +1200,15 @@ void diffcore_rename_extended(struct diff_options *options,
/* cost matrix sorted by most to least similar pair */
STABLE_QSORT(mx, dst_cnt * NUM_CANDIDATE_PER_DST, score_compare);
- rename_count += find_renames(mx, dst_cnt, minimum_score, 0);
+ rename_count += find_renames(mx, dst_cnt, minimum_score, 0,
+ &info, dirs_removed);
if (want_copies)
- rename_count += find_renames(mx, dst_cnt, minimum_score, 1);
+ rename_count += find_renames(mx, dst_cnt, minimum_score, 1,
+ &info, dirs_removed);
free(mx);
trace2_region_leave("diff", "inexact renames", options->repo);
cleanup:
- /*
- * Now that renames have been computed, compute dir_rename_count */
- if (dirs_removed && dir_rename_count)
- compute_dir_rename_counts(&info, dirs_removed, dir_rename_count);
-
/* At this point, we have found some renames and copies and they
* are recorded in rename_dst. The original list is still in *q.
*/
--
gitgitgadget
