[PATCH v3 10/10] x86-64: Intel64 adjustments for insns dealing with far pointers

[H.J. Lu]

On Mon, Jan 20, 2020 at 2:12 AM Jan Beulich <jbeulich@suse.com> wrote:
>
> On 17.01.2020 19:06, H.J. Lu wrote:
> > On Fri, Jan 17, 2020 at 3:48 AM Jan Beulich <jbeulich@suse.com> wrote:
> >>
> >> On 16.01.2020 21:24,  H.J. Lu  wrote:
> >>> We should improve gas documentation.  The current far branches
> >>> work fine.  Why bother to add new far branches without giving
> >>> developer a clue how to use them?
> >>
> >> That's the subject of CPU documentation, not that of any assembler.
> >> The current far branches "work fine" as far as they're being made
> >> accessible (encodable) by gas. The 64-bit forms Intel CPUs support
> >> didn't work fine at all (because one had to use hand crafted REX.W
> >> prefixes), as per Andrew's bug report. There's no difference here
> >> to the prior work you did to support the Intel64 / AMD64
> >> differences for certain other insns - you've simply made gas
> >> capable of properly encoding them in a vendor dependent manner.
> >> You didn't accompany this with any documentation explaining "how
> >> to use" these. If, retroactively, you think this should have been
> >> accompanied by such documentation, may I ask that you add such,
> >
> > Yes, it is not very obvious how to use them, we should add some
> > documentation.   Which one do you have in mind?
>
> All which currently have the Intel64 or AMD64 attribute. If all
> present ones had extra documentation, then (as said) it would be
> more obvious that _and_ what documentation needs/wants adding
> for ones covered anew.

Let's start with one first.  Please name one.

-- 
H.J.