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Date: Tue, 6 Dec 2011 13:59:24 +0400
From: Solar Designer <solar@...nwall.com>
To: john-dev@...ts.openwall.com
Subject: Re: Use of ICC

On Mon, Dec 05, 2011 at 08:07:42PM -0500, Erik Winkler wrote:
> On Dec 5, 2011, at 12:16 PM, Solar Designer wrote:
> > What exactly did you do?  Did you just comment out this one line or did
> > you make any other changes as well - e.g., edit adjacent lines in
> > x86-64.S or disable CPU detection in x86-64.h?
> 
> Just commented out the xgetbv line in x86-64.S.

This makes me wonder whether the code in question is being run at all or
not (in your build).  Can you try replacing the instruction with hlt,
then running that build?  (It should crash.  If it does not crash, then
the code is probably not being run.)

> > Instead of those changes, can you try replacing the xgetbv line with:
> > 
> > .byte 0x0f, 0x01, 0xd0
> > 
> > (raw opcode for the same instruction).  What happens when you do this?
> 
> It compiles just fine with this code substituted for xgetbv in x86-64.S

Sure, but does it run just as well?

Thanks,

Alexander

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