Re: [PATCH 0/3] perf: script: Intro capstone disasm engine to show instruction trace

[Changbin Du <changbin.du@huawei.com>]

On Tue, Jan 16, 2024 at 05:53:40AM -0800, Andi Kleen wrote:
> Changbin Du <changbin.du@huawei.com> writes:
> 
> > This series introduces capstone disassembler engine to print instructions of
> > Intel PT trace, which was printed via the XED tool.
> 
> FWIW at least on x86 in my experience capstone isn't that great an
> disassembler. I used it in another project and ran into many decoding bugs.
> They're mostly in obscure corners, but can be fairly annoying.
>
If so, I will preserve the old --xed option as an alternate.

> My other concern with your patchkit is that you change the default
> output formats. Since perf script is often used with scripts
> (as the name implies) there is a certain expectation that the output
> remains stable and parse-able. There are actually use cases where
> the raw bytes "insn" output is needed.
> 
> I would rather define new perf script output types for the new decoded output,
> but keep the old alone.
Agreed. What about these?
  - Add a new field 'insn_disam' to display decoded output.
  - Add params to '--insn-trace' option, that is '--insn-trace=[raw|disam]'.
    'raw' is the default value.

> 
> -Andi

-- 
Cheers,
Changbin Du