[PATCH 05/10] diff --color-moved: call comparison function directly

["Phillip Wood via GitGitGadget" <gitgitgadget@xxxxxxxxx>]

From: Phillip Wood <phillip.wood@xxxxxxxxxxxxx>

Calling xdiff_compare_lines() directly rather than using a function
pointer from the hash map reduces the time very slightly but more
importantly it will allow us to easily combine pmb_advance_or_null()
and pmb_advance_or_null_multi_match() in the next commit.

Before this change
Benchmark #1: bin-wrappers/git diff --diff-algorithm=myers --color-moved --no-color-moved-ws v2.28.0 v2.29.0
  Time (mean ± σ):      1.136 s ±  0.004 s    [User: 1.079 s, System: 0.053 s]
  Range (min … max):    1.130 s …  1.141 s    10 runs

After this change
Benchmark #1: bin-wrappers/git diff --diff-algorithm=myers --color-moved --no-color-moved-ws v2.28.0 v2.29.0
  Time (mean ± σ):      1.118 s ±  0.003 s    [User: 1.062 s, System: 0.053 s]
  Range (min … max):    1.114 s …  1.121 s    10 runs

Signed-off-by: Phillip Wood <phillip.wood@xxxxxxxxxxxxx>
---
 diff.c | 11 +++++++----
 1 file changed, 7 insertions(+), 4 deletions(-)

diff --git a/diff.c b/diff.c
index 5d5d168107a6..c8fdfc9049bb 100644
--- a/diff.c
+++ b/diff.c
@@ -995,17 +995,20 @@ static void add_lines_to_move_detection(struct diff_options *o,
 }
 
 static void pmb_advance_or_null(struct diff_options *o,
-				struct moved_entry *match,
-				struct hashmap *hm,
+				struct emitted_diff_symbol *l,
 				struct moved_block *pmb,
 				int pmb_nr)
 {
 	int i;
+	unsigned flags = o->color_moved_ws_handling & XDF_WHITESPACE_FLAGS;
+
 	for (i = 0; i < pmb_nr; i++) {
 		struct moved_entry *prev = pmb[i].match;
 		struct moved_entry *cur = (prev && prev->next_line) ?
 				prev->next_line : NULL;
-		if (cur && !hm->cmpfn(o, &cur->ent, &match->ent, NULL)) {
+		if (cur && xdiff_compare_lines(cur->es->line, cur->es->len,
+						l->line, l->len,
+						flags)) {
 			pmb[i].match = cur;
 		} else {
 			pmb[i].match = NULL;
@@ -1154,7 +1157,7 @@ static void mark_color_as_moved(struct diff_options *o,
 		    COLOR_MOVED_WS_ALLOW_INDENTATION_CHANGE)
 			pmb_advance_or_null_multi_match(o, l, pmb, pmb_nr);
 		else
-			pmb_advance_or_null(o, match, hm, pmb, pmb_nr);
+			pmb_advance_or_null(o, l, pmb, pmb_nr);
 
 		pmb_nr = shrink_potential_moved_blocks(pmb, pmb_nr);
 
-- 
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