GNU bug report logs - #17576
[PATCH] dfa: speed-up at initial state

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Reported by: Norihiro Tanaka <noritnk <at> kcn.ne.jp>

Date: Sat, 24 May 2014 03:33:01 UTC

Severity: normal

Tags: patch

Done: Paul Eggert <eggert <at> cs.ucla.edu>

Bug is archived. No further changes may be made.

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Message #26 received at 17576 <at> debbugs.gnu.org (full text, mbox):

From: Paul Eggert <eggert <at> cs.ucla.edu>
To: 17576 <at> debbugs.gnu.org, Norihiro Tanaka <noritnk <at> kcn.ne.jp>
Subject: Re: [PATCH] dfa: speed-up at initial state
Date: Fri, 30 May 2014 00:31:28 -0700
I don't think we need to complicate the code to improve optimization 
with older compilers.  People who really care about performance will use 
newer compilers anyway.  So let's focus on 
0001-dfa-speed-up-at-initial-state.patch.

I confirmed your performance results on my platform: the change makes 
test case "k" about 60% faster and test case "l" about 14% slower.  At 
this point we're just in bugfix mode so this patch can wait.  It'd be 
nice if it didn't slow down the short-line case so much.  Also, I wonder 
how well this change works for "typical" searches.  (I realize that 
"typical" is hard to define....)




This bug report was last modified 10 years and 318 days ago.

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