Re: [PATCH v3 3/4] perf annotate: add powerpc support

[Ravi Bangoria]

Hi Arnaldo,

On Friday 08 July 2016 02:01 PM, Michael Ellerman wrote:
> Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxxxxxxx> writes:
>
> > On Wednesday 06 July 2016 03:38 PM, Michael Ellerman wrote:
> >
> > I've sent v4 which enables annotate for bctr' instructions.
> >
> > for 'bctr', it will show down arrow(indicate jump) and 'bctrl' will show
> > right arrow(indicate call). But no navigation options will be provided.
> > By pressing Enter key on that, message will be shown that like
> > "Invalid target"
> Great thanks.

I've sent v4 series. Please review it.

-Ravi

> > > > > It doesn't look like we have the opcode handy here? Could we get it somehow?
> > > > > That would make this a *lot* more robust.
> > > > objdump prints machine code, but I don't know how difficult that would
> > > > be to parse to get opcode.
> > > Normal objdump -d output includes the opcode, eg:
> > >
> > > c00000000000886c:       2c 2c 00 00     cmpdi   r12,0
> > >                           ^^^^^^^^^^^
> > >
> > > The only thing you need to know is the endian and you can reconstruct
> > > the raw instruction.
> > >
> > > Then you can just decode the opcode, see how we do it in the kernel with
> > > eg. instr_is_relative_branch().
> > I'm sorry. I was thinking that you wants to show opcodes with perf
> > annotate. But you were asking to use opcode instead of parsing
> > instructions.
> Yeah.
>
> > This looks like rewrite parsing code. I don't know whether there is any
> > library already available for this which we can directly use. I'm thinking
> > about this.
> OK don't worry about it for now. We should get this merged for starters
> and we can always improve it later.
>
> cheers