An ia32 LOCK/XADD bug.

[Maciej W. Rozycki]

On Thu, 17 May 2001, H . J . Lu wrote:

> > > 2. If "lock xadd %edx,%edx" is really an illegal instruction on ia32,
> > > how should we fix gas to detect that?
> > 
> > Some IA-32 specific code has to check that an instruction with a lock
> > prefix always has a memory operand.  Don't know where to insert this.
> 
> It may be tough. I can put in some testcases to make gas to fail :-).

 I don't think such a check belongs to gas as "lock; xadd %edx,%edx" is
valid assembly code even if it faults when executed. 

-- 
+  Maciej W. Rozycki, Technical University of Gdansk, Poland   +
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