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Mail Archives: djgpp/2007/10/24/23:06:51

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Date: Wed, 24 Oct 2007 23:06:39 -0400
Message-Id: <200710250306.l9P36dqi002391@envy.delorie.com>
From: DJ Delorie <dj AT delorie DOT com>
To: djgpp AT delorie DOT com
In-reply-to: <ffp07f$66t$1@aioe.org> (do_not_have@nohavenot.cmm)
Subject: Re: Using inline asm
References: <471FEAC8 DOT 5179 DOT 2FAB88DB AT gerritvn DOT gpvno DOT co DOT za> <200710250120 DOT l9P1KEb2032374 AT envy DOT delorie DOT com> <ffp07f$66t$1 AT aioe DOT org>
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> > >    asm ("cpuid" : "=a" (iRet));
> 
> Huh?  I'm sure I missed something...  That takes care of eax for cpuid, but
> that ignores ebx, ecx, and edx.  cpuid trashes those four registers whether
> he returns them or not, correct?   How does GCC correct the other three?

   asm ("cpuid" : "=a" (iRet) : : "ebx", "ecx", "edx");

Or something like that.

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