From: oml1 AT Ra DOT MsState DOT Edu (Owen LaGarde)
Newsgroups: comp.os.msdos.djgpp
Subject: AT&T syntax reference for i386 asm -- recommend?
Date: 20 May 1997 16:27:19 GMT
Organization: Mississippi State University
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Distribution: usa
Message-ID: <5lsjd7$ri5$1@NNTP.MsState.Edu>
NNTP-Posting-Host: ra.msstate.edu
To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Precedence: bulk

   I'm new to DJGPP, so it wasn't until I started moving some old register
service stubs -- rot's, mul's, etc -- that I realised I was way deficient
in the AT&T syntax and gcc inline use.  Can anyone recommend a good opcode 
ref/gcc inline guide/examples source better than the gcc.inf node on C 
extentions?  For starters, I'd like to find the recommended way to do simple 
one-steppers like the following -- both in syntax and, since there's so many 
notes about the ability to optimize over inline asm, whether or not it's 
better to inline things like this in C func's or put them in asm func to be 
called from C, etc.

   mov  ax, lval       ;lval in C
   mov  cx, cout       ;ditto
   rotl ax, cx         ;b-rot ax by cx, ret in ax

   Is there any one approach to this level of asm that's widely accepted as
best/fastest?
-- 
 Owen LaGarde                           |     Performance prediction through
 Forest Products Research Laboratory    |       AI-driven process simulation
 Mississippi State University           | 
 oml1 AT ra DOT msstate DOT edu (130.18.80.10)     |   "... Oh, what a Tangled Web ..."