From mboxrd@z Thu Jan  1 00:00:00 1970
Date: Mon, 20 Oct 2008 17:03:28 -0400
From: Nathaniel W Filardo <nwf@cs.jhu.edu>
To: Fans of the OS Plan 9 from Bell Labs <9fans@9fans.net>
Message-ID: <20081020210328.GM4216@masters10.cs.jhu.edu>
References: <20081020072645.GJ4216@masters10.cs.jhu.edu>
	<244fbb7370d6d3e7069c3e06c1116877@terzarima.net>
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Subject: Re: [9fans] What's so special about seek() ?
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On Mon, Oct 20, 2008 at 10:11:22PM +0100, Charles Forsyth wrote:
> >Forgive my ignorance, but I don't see how the code in question relates to
> >returning a 64-bit value?
> 				MOVL a+0(FP),CX
> 				MOVL AX,0(CX)
> 				MOVL AX,4(CX)
>=20
> that's how a 64-bit value is returned on 32-bit machines:
> similar to returning a structure, the caller passes a
> hidden first argument referring to the 64-bit return location.
> in this case, since -1 is already in AX, storing that in both 32-bit
> parts of the 64-bit value produces -1LL

Oh interesting.  Thanks for the clarification.  I had thought 64 bit returns
were done in %eax and %edx.  Sorry for the noise.
--nwf;

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