From: Fabrice ILPONSE <fabrice AT asim DOT lip6 DOT fr>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Inline assembly in djgpp
Date: Thu, 14 May 1998 14:26:26 +0200
Organization: Universites Paris VI/Paris VII - France
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Herman Schoenfeld wrote:
> 
> How do i do a "byte ptr" in djgpp inline asm?
> 
> ie.
> 
> mov ax, byte ptr a
> asm ("movw ??, %%ax": : "g" (a): "ax");

 	movzwb ??,%%ax // unsigned
or      movswb ??,%%ax // signed

	if i remember...
> 
> Is there any possible way to use variable names in inline assembly?
> 
> int i=10, j=20;
> asm ("movw %_i, %%eax": : "eax");
> asm ("movw %_j, %%ebx": : "ebx");

2 ways:
local variables:

	asm ("movw %0, %%ebx": : "m" j); // i'm not sure about 'm'

globals: (and perhaps locals)
	int j asm ("myvar_j");
	asm ("movw myvar_j, %%ebx");
  
> 
> I know that works, however if the above assembly is in a function and
> the variables i,j are declared publically, then it decides to load those
> not the ones declared inside the function. Why doesn't the scope rules
> seem to affect djgpp inline asm? Or, is there a way around this?

-- 
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	+-+-+	Fabrice ILPONSE
	  |	email: fabrice AT asim DOT lip6 DOT fr
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