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From: Jeremy Fitzhardinge <jeremy@goop.org>
To: Denis Cheng <crquan@gmail.com>
Cc: trivial@kernel.org, linux-kernel@vger.kernel.org
Subject: Re: [PATCH] trivial: the memset operation on a automatic array	variable should be optimized out by data initialization
Date: Mon, 18 Jun 2007 10:07:21 -0700	[thread overview]
Message-ID: <4676BBC9.3060707@goop.org> (raw)
In-Reply-To: <467658db.0f98600a.5a55.ffffdd79@mx.google.com>

Denis Cheng wrote:
> From: Denis Cheng <crquan@gmail.com>
>
> the explicit memset call could be optimized out by data initialization,
> thus all the fill working can be done by the compiler implicitly.
>   

How does the generated code change?  Does gcc do something stupid like
statically allocate a prototype structure full of zeros, and then memcpy
it in?  Or does it generate a series of explicit assignments for each
member?  Or does it generate a memset anyway?

Seems to me that this gives gcc the opportunity to be more stupid, and
the only right answer is what we're doing anyway.

    J

  parent reply	other threads:[~2007-06-18 17:08 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2007-06-18 10:05 [PATCH] trivial: the memset operation on a automatic array variable should be optimized out by data initialization Denis Cheng
2007-06-18 10:25 ` Robert P. J. Day
2007-06-18 14:24   ` WANG Cong
2007-06-18 17:07 ` Jeremy Fitzhardinge [this message]
2007-06-19 13:27   ` Adrian Bunk
2007-06-21 13:21   ` rae l
2007-06-23  5:15 Denis Cheng
2007-06-23  7:59 ` Oleg Verych
2007-06-23 13:13   ` Adrian Bunk
2007-06-23 13:41     ` Oleg Verych
2007-06-23 13:57       ` Adrian Bunk
2007-06-23 15:21         ` Segher Boessenkool
2007-06-24 12:58   ` rae l
2007-06-24 22:25     ` Oleg Verych
2007-06-24 22:15       ` Arjan van de Ven
2007-06-24 23:23         ` Benjamin LaHaise
2007-06-25  0:09           ` Arjan van de Ven
2007-06-25  0:12             ` Benjamin LaHaise
2007-06-25  0:23               ` Arjan van de Ven

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