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Re: Discussion: What is unspec_volatile?

On 11/13/2010 05:10 PM, H.J. Lu wrote:
On Sat, Nov 13, 2010 at 8:01 AM, Paolo Bonzini<bonzini@gnu.org> wrote:
On 11/13/2010 04:28 PM, H.J. Lu wrote:

VZEROUPPER is no-nop to executions. But it isn't no-nop for performance. 

IIUC it's a noop as GCC uses it.  You could use it in 256-bit mode and it
would be valid, but not a noop.


That is besides the point. I just pointed out that there was no register barrier
for IRA.

And I was pointing out that the machine description is wrong :)

Paolo

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