Received-SPF: pass (google.com: domain of linux-kernel+bounces-172538-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Date: Wed, 8 May 2024 08:57:51 +0900
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
To: Namhyung Kim <namhyung@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>, Ian Rogers
 <irogers@google.com>, Kan Liang <kan.liang@linux.intel.com>, Jiri Olsa
 <jolsa@kernel.org>, Adrian Hunter <adrian.hunter@intel.com>, Peter Zijlstra
 <peterz@infradead.org>, Ingo Molnar <mingo@kernel.org>, LKML
 <linux-kernel@vger.kernel.org>, linux-perf-users@vger.kernel.org, Masami
 Hiramatsu <mhiramat@kernel.org>
Subject: Re: [PATCH] perf dwarf-aux: Print array type name with "[]"
Message-Id: <20240508085751.a1a5dbd31e1fa7d4e80cdd85@kernel.org>
In-Reply-To: <20240507041338.2081775-1-namhyung@kernel.org>
References: <20240507041338.2081775-1-namhyung@kernel.org>
Precedence: bulk
Mime-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit

On Mon,  6 May 2024 21:13:38 -0700
Namhyung Kim <namhyung@kernel.org> wrote:

> It's confusing both pointers and arrays are printed as *.  Let's print
> array types with [] so that we can identify them easily.  Although it's
> interchangable, sometimes it can cause confusion with size like in the
> below example.
> 
> Note that it is not the same with C syntax where it goes to the variable
> names, but we want to have it in the type names (like in Go language).
> 
> Before:
>   mov [20] 0x68(reg5) -> reg0 type='struct page**' size=0x80 (die:0x4e61d32)
> 
> After:
>   mov [20] 0x68(reg5) -> reg0 type='struct page*[]' size=0x80 (die:0x4e61d32)
> 

Good improvement!

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Thank you!

> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/dwarf-aux.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
> index c0a492e65388..ec988f294497 100644
> --- a/tools/perf/util/dwarf-aux.c
> +++ b/tools/perf/util/dwarf-aux.c
> @@ -1110,8 +1110,10 @@ int die_get_typename_from_type(Dwarf_Die *type_die, struct strbuf *buf)
>  	const char *tmp = "";
>  
>  	tag = dwarf_tag(type_die);
> -	if (tag == DW_TAG_array_type || tag == DW_TAG_pointer_type)
> +	if (tag == DW_TAG_pointer_type)
>  		tmp = "*";
> +	else if (tag == DW_TAG_array_type)
> +		tmp = "[]";
>  	else if (tag == DW_TAG_subroutine_type) {
>  		/* Function pointer */
>  		return strbuf_add(buf, "(function_type)", 15);
> -- 
> 2.45.0.rc1.225.g2a3ae87e7f-goog
> 


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>