From:	brennan AT mack DOT rt66 DOT com (Brennan "The Rev. Bas" Underwood)
Newsgroups:	comp.os.msdos.djgpp
Subject:	Re: Bitwise ASM with DJGPP GCC
Date:	18 May 1997 17:52:06 -0600
Organization:	Acid Brain
Lines:	35
Distribution:	world
Message-ID:	<5lo4n6$apu$1@mack.rt66.com>
References:	<1997051321301977565 AT zetnet DOT co DOT uk>
NNTP-Posting-Host:	mack.rt66.com
To:	djgpp AT delorie DOT com
DJ-Gateway:	from newsgroup comp.os.msdos.djgpp

In article <1997051321301977565 AT zetnet DOT co DOT uk>,
Keith Hull  <keithh AT zetnet DOT co DOT uk> wrote:
>Hi everyone,
>
>I would like some help with GCC and inline asm (i've looked at 
>Brennan's Guide to Inline ASM - it seems to make sense ;) .... heres 
>my problem..
>
>asm ("rorl _val, _num_of_rotates");
>asm ("roll _val, _num_of_rotates");
>asm ("sall _val, _num_of_rotates");
>asm ("sarl _val, _num_of_rotates");
>asm ("shll _val, _num_of_rotates");
>asm ("shrl _val, _num_of_rotates");
>
>none of the above statements compile under GCC!! They seem to have a 
>problem with the first operand! 
>
>Can anyone shed any light, i'm completely baffled.

You can't have that many memory operands, and you have them backwards.

You could have done "rorl $4, _val" or "rorl %cl, _val".

movb _num_of_rotates, %cl
rorl %cl, %ecx

Would do what I think you want.


Brennan
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