Re: [PATCH] trivial: the memset operation on a automatic arrayvariable should be optimized out by data initialization

From: Arjan van de Ven
Date: Sun Jun 24 2007 - 20:09:53 EST


On Sun, 2007-06-24 at 19:23 -0400, Benjamin LaHaise wrote:
> On Sun, Jun 24, 2007 at 03:15:17PM -0700, Arjan van de Ven wrote:
> > we should just alias our memset to the __builtin one, and then provide a
> > generic one from lib/ for the cases gcc needs to do a fallback.
>
> The last time I checked, gcc generated horrible badly performing code for
> builtin memset/memcpy() when -Os is specified.

if you care about the last cycle, don't specify -Os but -O2.
simple as that... you get what you tell the compiler you want.

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