[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: uniq i18n implementation
From: |
Paul Eggert |
Subject: |
Re: uniq i18n implementation |
Date: |
Mon, 14 Aug 2006 09:22:31 -0700 |
User-agent: |
Gnus/5.1008 (Gnus v5.10.8) Emacs/21.4 (gnu/linux) |
Pádraig Brady <address@hidden> writes:
> There seems to be serious overhead with strcoll on glibc-2.3.5-10 at least.
We can fix the performance problem for that particular test case as
follows. I installed this (diff -pubw format):
2006-08-14 Paul Eggert <address@hidden>
* memcoll.c (memcoll): Optimize for the common case where the
arguments are bytewise equal.
--- memcoll.c.~1.13.~ 2005-09-21 23:05:39.000000000 -0700
+++ memcoll.c 2006-08-14 09:18:44.000000000 -0700
@@ -38,6 +38,14 @@ memcoll (char *s1, size_t s1len, char *s
#if HAVE_STRCOLL
+ /* strcoll is slow on many platforms, so check for the common case
+ where the arguments are bytewise equal. Otherwise, walk through
+ the buffers using strcoll on each substring. */
+
+ if (s1len == s2len && memcmp (s1, s2, s1len) == 0)
+ diff = 0;
+ else
+ {
char n1 = s1[s1len];
char n2 = s2[s2len];
@@ -71,6 +79,7 @@ memcoll (char *s1, size_t s1len, char *s
s1[s1len - 1] = n1;
s2[s2len - 1] = n2;
+ }
#else