Message-Id: <m0zvLmw-000S2KC@inti.gov.ar>
Comments: Authenticated sender is <salvador AT natacha DOT inti DOT gov DOT ar>
From: "Salvador Eduardo Tropea (SET)" <salvador AT inti DOT gov DOT ar>
Organization: INTI
To: Christian Hofrichter <ChristianHofrichter AT gmx DOT de>, djgpp AT delorie DOT com
Date: Wed, 30 Dec 1998 10:39:14 +0000
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Subject: Re: register-arithmetic
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Reply-To: djgpp AT delorie DOT com

Christian Hofrichter <ChristianHofrichter AT gmx DOT de> wrote:

> If I tell gcc explicitely what for varibales it shall load in which
> register and do some arithmetic to them, can I be sure that only this
> register is used for that arithemtic or could it be that other
> registerts are temporarly allocated ? The following code should
> illustate that:
> 
> Example :        asm("    ":
>                                     :"a"(x*y+1) );
> 
> 
> So can I be sure that only eax is used for this multiplication and
> addition or could it be that let's say  ebx is allocated to do some
> arithmetic temorarly.

You can't. Is just impossible to make x*y using only one register.

SET 
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