Re: [patch 13/17] Immediate Values - x86 Optimization

[H. Peter Anvin]

Mathieu Desnoyers wrote:
> Ok. Sorry, it's been a few months since we looked at this. So the =q
> opcode lets the compiler choose instructions with or without REX prefix.
> We can allow this because 
>
> - We don't need the opcode length in the stop_machine_run() version
> - we support variable length opcode in the nmi-safe version
>
> Am I remembering correctly now ?

Yes.  Both =r and =q allow REX opcodes.

	-hpa
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