From 0e488f173257e5ab766267ac5a5c4c9f3f1ce343 Mon Sep 17 00:00:00 2001 From: Phillip Wood Date: Thu, 9 Dec 2021 10:30:05 +0000 Subject: [PATCH] diff --color-moved: shrink potential moved blocks as we go Rather than setting `match` to NULL and then looping over the list of potential matched blocks for a second time to remove blocks with no matches just filter out the blocks with no matches as we go. Signed-off-by: Phillip Wood Signed-off-by: Junio C Hamano --- diff.c | 44 ++++++++------------------------------------ 1 file changed, 8 insertions(+), 36 deletions(-) diff --git a/diff.c b/diff.c index 51f092e724..626fd47aa0 100644 --- a/diff.c +++ b/diff.c @@ -996,12 +996,12 @@ static void add_lines_to_move_detection(struct diff_options *o, static void pmb_advance_or_null(struct diff_options *o, struct emitted_diff_symbol *l, struct moved_block *pmb, - int pmb_nr) + int *pmb_nr) { - int i; + int i, j; unsigned flags = o->color_moved_ws_handling & XDF_WHITESPACE_FLAGS; - for (i = 0; i < pmb_nr; i++) { + for (i = 0, j = 0; i < *pmb_nr; i++) { int match; struct moved_entry *prev = pmb[i].match; struct moved_entry *cur = (prev && prev->next_line) ? @@ -1015,38 +1015,12 @@ static void pmb_advance_or_null(struct diff_options *o, match = cur && xdiff_compare_lines(cur->es->line, cur->es->len, l->line, l->len, flags); - if (match) - pmb[i].match = cur; - else - moved_block_clear(&pmb[i]); - } -} - -static int shrink_potential_moved_blocks(struct moved_block *pmb, - int pmb_nr) -{ - int lp, rp; - - /* Shrink the set of potential block to the remaining running */ - for (lp = 0, rp = pmb_nr - 1; lp <= rp;) { - while (lp < pmb_nr && pmb[lp].match) - lp++; - /* lp points at the first NULL now */ - - while (rp > -1 && !pmb[rp].match) - rp--; - /* rp points at the last non-NULL */ - - if (lp < pmb_nr && rp > -1 && lp < rp) { - pmb[lp] = pmb[rp]; - memset(&pmb[rp], 0, sizeof(pmb[rp])); - rp--; - lp++; + if (match) { + pmb[j] = pmb[i]; + pmb[j++].match = cur; } } - - /* Remember the number of running sets */ - return rp + 1; + *pmb_nr = j; } static void fill_potential_moved_blocks(struct diff_options *o, @@ -1181,9 +1155,7 @@ static void mark_color_as_moved(struct diff_options *o, continue; } - pmb_advance_or_null(o, l, pmb, pmb_nr); - - pmb_nr = shrink_potential_moved_blocks(pmb, pmb_nr); + pmb_advance_or_null(o, l, pmb, &pmb_nr); if (pmb_nr == 0) { int contiguous = adjust_last_block(o, n, block_length);