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From: Nai Xia <nai.xia@gmail.com>
Reply-To: nai.xia@gmail.com
To: Andi Kleen <ak@linux.intel.com>
Subject: Question about missing "cld" in x86 string assembly code
Date: Sat, 17 Dec 2011 22:58:24 +0800
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Hi Andi, 

Seems I used a stale email address of you from a related git commit log,
so this is a resend, sorry.

=======
Hi, 

I notice that all x86 assembly code for string operations containing
"scasb, lodsb", etc does not have "cld" at the beginning.
Is this 100% safe? 
Or in other words, how could we be sure that
there is no "std" generated by compiler somewhere just before
the string operations? 


Thanks,

Nai