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From: "Rod Pemberton" <do_not_have AT nohavenot DOT cmm>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Using inline asm
Date: Thu, 25 Oct 2007 04:39:14 -0400
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To: djgpp AT delorie DOT com
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"DJ Delorie" <dj AT delorie DOT com> wrote in message
news:200710250306 DOT l9P36dqi002391 AT envy DOT delorie DOT com...
>
> > > >    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.

Thanks.  Okay, it doesn't, so correct the code...  I wasn't sure if the asm
directive inserted a pusha; popa combination into the stackframe, say
instead of push ebp; pop ebp, or used some other method.  That might mess up
returns...

RP