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Mail Archives: djgpp/1999/08/27/10:55:28

Date: Fri, 27 Aug 1999 14:16:33 +0200
From: Hans-Bernhard Broeker <broeker AT physik DOT rwth-aachen DOT de>
Message-Id: <199908271216.OAA00364@acp3bf.physik.rwth-aachen.de>
To: djgpp AT delorie DOT com
Subject: Re: Assembly Question, sarl, sall...
Newsgroups: comp.os.msdos.djgpp
Organization: RWTH Aachen, III. physikalisches Institut B
X-Newsreader: TIN [version 1.2 PL2]
Reply-To: djgpp AT delorie DOT com

In article <199908262334 DOT TAA19011 AT delorie DOT com> you wrote:
> Hey, an assembly question.  Could be offtopic but how I got there is not.

> I was looking at some gcc generated assembly code and the compiler made big
> use of the opcodes sarl and sall.  Are these faster then bit shifts? 

They *are* the bit shifts. sarl = 'Shift ARithmetic Right, Long
argument'. There are two types of 'bit shift' for (possibly) signed
arguments.  One is 'logical' shift, the other is 'arithmetic'.

> another thing, what does the EA byte stand for? (its not supposed to be
> eax!)

Context please. Just a rough idea: it might be the segment override
operator. It was coded explicitly in some DJGPP assembly to work
around bugs in gas.

--
Hans-Bernhard Broeker (broeker AT physik DOT rwth-aachen DOT de)
Even if all the snow were burnt, ashes would remain.

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