From 1ad69eb0dcfa61e175e7540517bd4e6e7a66822a Mon Sep 17 00:00:00 2001 From: Elijah Newren Date: Sat, 27 Feb 2021 00:30:46 +0000 Subject: diffcore-rename: compute dir_rename_counts in stages 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. Reviewed-by: Derrick Stolee Signed-off-by: Elijah Newren Signed-off-by: Junio C Hamano --- diffcore-rename.c | 110 ++++++++++++++++++++++++++++++++++-------------------- 1 file changed, 70 insertions(+), 40 deletions(-) (limited to 'diffcore-rename.c') diff --git a/diffcore-rename.c b/diffcore-rename.c index 2cf9c47c63..10f8f4a301 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. */ -- cgit v1.2.3