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From: "Joseph S. Myers" <joseph@codesourcery.com>
To: Steven Bosscher <stevenb.gcc@gmail.com>
Cc: GCC Mailing List <gcc@gcc.gnu.org>
Subject: Re: Where does the time go?
Date: Thu, 20 May 2010 19:36:00 -0000	[thread overview]
Message-ID: <Pine.LNX.4.64.1005201931130.2047@digraph.polyomino.org.uk> (raw)
In-Reply-To: <AANLkTimYQASWjXGLX9W49v-1Sy3VsLIaybYWD2oTe808@mail.gmail.com>

On Thu, 20 May 2010, Steven Bosscher wrote:

> * The C front end (preprocessing+lexing+parsing) costs ~17%. For an
> optimizing compiler with so many passes, this is quite a lot.

Unlike C++ where a lot of speedups were done around 2004-5, I don't think 
much has been done about speeding up the C front end outside the 
preprocessor, so there are likely to be lots of opportunities available 
(there are probably still a fair number for C++ as well).

Preprocessor (including preprocessed output) speed is of relevance for use 
with tools such as distcc, and whole-compilation speed is of obvious 
relevance for general use of the compiler.  Front-end-only speed 
(-fsyntax-only, approximately) is less important on its own as that's not 
a normal compiler use (I think) - it's only relevant as a contribution to 
the speed of a whole compilation.

-- 
Joseph S. Myers
joseph@codesourcery.com

  parent reply	other threads:[~2010-05-20 19:36 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-05-20 15:55 Steven Bosscher
2010-05-20 19:16 ` Vladimir Makarov
2010-05-20 19:57   ` Toon Moene
2010-05-20 20:36   ` Steven Bosscher
2010-05-20 20:54     ` Duncan Sands
2010-05-20 21:14       ` Steven Bosscher
2010-05-23 19:09         ` Joseph S. Myers
2010-05-24 17:00           ` Mark Mitchell
2010-05-24 21:07             ` Steven Bosscher
2010-05-24 23:22               ` Mark Mitchell
2010-05-25  1:20                 ` Joseph S. Myers
2010-05-20 21:09     ` Ian Lance Taylor
2010-05-20 21:14       ` Xinliang David Li
2010-05-20 21:18         ` Steven Bosscher
2010-05-20 21:21           ` Xinliang David Li
2010-05-21 10:54             ` Richard Guenther
2010-05-21 13:26               ` Jan Hubicka
2010-05-21 15:06                 ` Richard Guenther
2010-05-21 15:49                   ` Jan Hubicka
2010-05-21 17:06               ` Xinliang David Li
2010-05-21 17:07                 ` Richard Guenther
2010-05-20 19:36 ` Joseph S. Myers [this message]
2010-05-20 20:35 ` Eric Botcazou
2010-05-20 20:42   ` Eric Botcazou
2010-05-21 20:43 ` Diego Novillo
2010-05-20 21:28 Bradley Lucier

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