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 <phillip.wood@dunelm.org.uk>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Phillip Wood 2021-12-09 10:30:05 +00:00 committed by Junio C Hamano
parent ff046a0066
commit 0e488f1732

44
diff.c
View File

@ -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);