From 0202a83b3d0de224a5d606958e3719244d546548 Mon Sep 17 00:00:00 2001
From: Norihiro Tanaka <address@hidden>
Date: Sun, 17 Nov 2019 07:20:41 +0900
Subject: [PATCH 1/2] grep: fix performance degration with previous patch

* src/kwsearch.c (Fexecute): Avoid unnecessary backwards in non-UTF8
multibyte locales.
---
 src/kwsearch.c |   15 ++++++++++++---
 1 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/kwsearch.c b/src/kwsearch.c
index 5edff79..f590d19 100644
--- a/src/kwsearch.c
+++ b/src/kwsearch.c
@@ -224,9 +224,18 @@ Fexecute (void *vcp, char const *buf, size_t size, size_t *match_size,
         goto success;
 
       /* We need a preceding mb_start pointer.  Use the beginning of line
-         if there is a preceding newline, else BUF.  */
-      char const *nl = memrchr (mb_start, eol, beg - mb_start);
-      mb_start = nl ? nl + 1 : buf;
+         if there is a preceding newline.  */
+      if (mb_check)
+        {
+           char const *nl = memrchr (buf, eol, beg - buf);
+           mb_start = nl ? nl + 1 : buf;
+        }
+      else
+        {
+           char const *nl = memrchr (mb_start, eol, beg - mb_start);
+           if (nl)
+             mb_start = nl + 1;
+        }
 
       /* Succeed if neither the preceding nor the following character is a
          word constituent.  If the preceding is not, yet the following
-- 
1.7.1