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Re: [PATCH] x86: Add .nop directive to assembler

On Mon, Feb 19, 2018 at 6:44 AM, Maciej W. Rozycki <> wrote:
> On Mon, 19 Feb 2018, H.J. Lu wrote:
>> >>  I have a feeling the default should wire in HANDLE_ALIGN somehow.  For
>> >> many targets, such as fixed instruction width RISC processors, there is
>> >> only going to be one way of filling a given amount of space with no-op
>> >> instructions, so I think there's no point in having code duplication
>> >> here.  And even if there are more ways possible for a given target, then
>> >> the `.align' way is still right even if suboptimal.
>> >
>> > How would you propose to express "I need three nop
>> > instructions aka 12 bytes from here" with just .align?  (Note: no matter
>> > how "here" is currently aligned!)
>> >
>> .align isn't the same as .nop.   However, HANDLE_ALIGN can be updated
>> to shared the same code with md_generate_nops, like what I did for x86.
>  Yes, that's what I meant.  It's an internal code wiring thing, not to be
> something observable by the user.

Let me work on it.


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