From: Timo Sirainen <timo.sirainen@open-xchange.com>
Date: Mon, 12 Jun 2023 14:33:59 +0000 (+0300)
Subject: lib-index: mail_index_seq_array_lookup() - Optimize append code path
X-Git-Tag: 2.4.0~2695
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=3097e0fd077fc04334764983a30440d7dee3c171;p=thirdparty%2Fdovecot%2Fcore.git

lib-index: mail_index_seq_array_lookup() - Optimize append code path
---

diff --git a/src/lib-index/mail-index-util.c b/src/lib-index/mail-index-util.c
index 2b27ae1e70..b61cf8d32f 100644
--- a/src/lib-index/mail-index-util.c
+++ b/src/lib-index/mail-index-util.c
@@ -88,6 +88,15 @@ static int mail_index_seq_record_cmp(const uint32_t *key_seq,
 bool mail_index_seq_array_lookup(const ARRAY_TYPE(seq_array) *array,
 				 uint32_t seq, unsigned int *idx_r)
 {
+	/* fast path: expect array to be usually appended to */
+	unsigned int count = array_count(array);
+	if (count > 0) {
+		const uint32_t *elem = array_back(array);
+		if (seq > *elem) {
+			*idx_r = count;
+			return FALSE;
+		}
+	}
 	return array_bsearch_insert_pos(array, &seq,
 					mail_index_seq_record_cmp, idx_r);
 }