Re: [PATCH v2 1/2] perf annotate: Handle x86 instruction suffix generally

[Arnaldo Carvalho de Melo <acme@kernel.org>]

Em Tue, Jun 06, 2023 at 11:06:58PM +0900, Masami Hiramatsu escreveu:
> On Wed, 24 May 2023 13:50:53 -0700
> Namhyung Kim <namhyung@kernel.org> wrote:
> 
> > In AT&T asm syntax, most of x86 instructions can have size suffix like
> > b, w, l or q.  Instead of adding all these instructions in the table,
> > we can handle them in a general way.
> > 
> > For example, it can try to find an instruction as is.  If not found,
> > assuming it has a suffix and it'd try again without the suffix if it's
> > one of the allowed suffixes.  This way, we can reduce the instruction
> > table size for duplicated entries of the same instructions with a
> > different suffix.
> > 
> > If an instruction xyz and others like xyz<suffix> are completely
> > different ones, then they both need to be listed in the table so that
> > they can be found before the second attempt (without the suffix).
> 
> Looks good to me.
> 
> Reviewed-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thanks, applied both patches.

- Arnaldo

 
> > 
> > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> > ---
> >  tools/perf/util/annotate.c | 22 ++++++++++++++++++++++
> >  1 file changed, 22 insertions(+)
> > 
> > diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> > index b708bbc49c9e..7f05f2a2aa83 100644
> > --- a/tools/perf/util/annotate.c
> > +++ b/tools/perf/util/annotate.c
> > @@ -70,6 +70,7 @@ struct arch {
> >  	struct ins_ops  *(*associate_instruction_ops)(struct arch *arch, const char *name);
> >  	bool		sorted_instructions;
> >  	bool		initialized;
> > +	const char	*insn_suffix;
> >  	void		*priv;
> >  	unsigned int	model;
> >  	unsigned int	family;
> > @@ -179,6 +180,7 @@ static struct arch architectures[] = {
> >  		.init = x86__annotate_init,
> >  		.instructions = x86__instructions,
> >  		.nr_instructions = ARRAY_SIZE(x86__instructions),
> > +		.insn_suffix = "bwlq",
> >  		.objdump =  {
> >  			.comment_char = '#',
> >  		},
> > @@ -720,6 +722,26 @@ static struct ins_ops *__ins__find(struct arch *arch, const char *name)
> >  	}
> >  
> >  	ins = bsearch(name, arch->instructions, nmemb, sizeof(struct ins), ins__key_cmp);
> > +	if (ins)
> > +		return ins->ops;
> > +
> > +	if (arch->insn_suffix) {
> > +		char tmp[32];
> > +		char suffix;
> > +		size_t len = strlen(name);
> > +
> > +		if (len == 0 || len >= sizeof(tmp))
> > +			return NULL;
> > +
> > +		suffix = name[len - 1];
> > +		if (strchr(arch->insn_suffix, suffix) == NULL)
> > +			return NULL;
> > +
> > +		strcpy(tmp, name);
> > +		tmp[len - 1] = '\0'; /* remove the suffix and check again */
> > +
> > +		ins = bsearch(tmp, arch->instructions, nmemb, sizeof(struct ins), ins__key_cmp);
> > +	}
> >  	return ins ? ins->ops : NULL;
> >  }
> >  
> > -- 
> > 2.41.0.rc0.172.g3f132b7071-goog
> > 
> 
> 
> -- 
> Masami Hiramatsu (Google) <mhiramat@kernel.org>

-- 

- Arnaldo