diff mbox series

[3/3] xdiff: simplify comparison

Message ID b0bc773f51e114d96ad6efd1ebd03fb6e7646288.1637148025.git.gitgitgadget@gmail.com (mailing list archive)
State Accepted
Commit 6b13bc32322dc64e52ef29c9f527746ad30d0ad8
Headers show
Series xdiff: speedup histogram diff | expand

Commit Message

Phillip Wood Nov. 17, 2021, 11:20 a.m. UTC 
From: Phillip Wood <phillip.wood@dunelm.org.uk>

Now that the histogram algorithm calls xdl_classify_record() it is no
longer necessary to use xdl_recmatch() to compare lines, it is
sufficient just to compare the hash values. This has a negligible
effect on performance.

Test                                  HEAD~1            HEAD
-----------------------------------------------------------------------------
4000.1: log -3000 (baseline)          0.19(0.12+0.07)   0.18(0.14+0.04) -5.3%
4000.2: log --raw -3000 (tree-only)   0.98(0.81+0.16)   0.98(0.79+0.18) +0.0%
4000.3: log -p -3000 (Myers)          4.81(4.23+0.56)   4.80(4.26+0.53) -0.2%
4000.4: log -p -3000 --histogram      5.83(5.11+0.70)   5.82(5.15+0.65) -0.2%
4000.5: log -p -3000 --patience       5.31(4.61+0.69)   5.30(4.54+0.75) -0.2%

Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
---
 xdiff/xdiffi.c | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)
diff mbox series

Patch

diff --git a/xdiff/xdiffi.c b/xdiff/xdiffi.c
index a4542c05b61..6a3b9280beb 100644
--- a/xdiff/xdiffi.c
+++ b/xdiff/xdiffi.c
@@ -392,10 +392,7 @@  static xdchange_t *xdl_add_change(xdchange_t *xscr, long i1, long i2, long chg1,
 
 static int recs_match(xrecord_t *rec1, xrecord_t *rec2, long flags)
 {
-	return (rec1->ha == rec2->ha &&
-		xdl_recmatch(rec1->ptr, rec1->size,
-			     rec2->ptr, rec2->size,
-			     flags));
+	return (rec1->ha == rec2->ha);
 }
 
 /*