On Sat, Nov 13, 2010 at 8:20 AM, Paolo Bonzini <bonz...@gnu.org> wrote: > On 11/13/2010 05:10 PM, H.J. Lu wrote: >> >> On Sat, Nov 13, 2010 at 8:01 AM, Paolo Bonzini<bonz...@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 :) >
Please tell me how I can tell IRA not to move ANY instructions across an instruction which is an no-op to executions. -- H.J.
