Re: [PATCH] Properly interpret indirect call in perf annotate.

[Namhyung Kim <namhyung@kernel.org>]

Hello,

On Thu, Aug 23, 2018 at 02:29:34PM +0200, Martin Liška wrote:
> The patch changes interpretation of:
> callq  *0x8(%rbx)
> 
> from:
>   0.26 │     → callq  *8
> to:
>   0.26 │     → callq  *0x8(%rbx)
> 
> in this can an address is followed by a register, thus
> one can't parse only address.

Also there's a case with no offset like:  callq  *%rbx


> 
> Signed-off-by: Martin Liška <mliska@suse.cz>
> ---
>  tools/perf/util/annotate.c | 10 ++++++++--
>  1 file changed, 8 insertions(+), 2 deletions(-)
> 
> 

> diff --git a/tools/perf/util/annotate.c b/tools/perf/util/annotate.c
> index e4268b948e0e..e32ead4744bd 100644
> --- a/tools/perf/util/annotate.c
> +++ b/tools/perf/util/annotate.c
> @@ -246,8 +246,14 @@ static int call__parse(struct arch *arch, struct ins_operands *ops, struct map_s
>  
>  indirect_call:
>  	tok = strchr(endptr, '*');
> -	if (tok != NULL)
> -		ops->target.addr = strtoull(tok + 1, NULL, 16);
> +	if (tok != NULL) {
> +		endptr++;
> +
> +		/* Indirect call can use a non-rip register and offset: callq  *0x8(%rbx).
> +		 * Do not parse such instruction.  */
> +		if (strstr(endptr, "(%r") == NULL)
> +			ops->target.addr = strtoull(endptr, NULL, 16);

It seems too x86-specific, what about this? (not tested)


indirect_call:
	tok = strchr(endptr, '*');
	if (tok != NULL) {
		endptr++;
		if (!isdigit(*endptr))
			return 0;

		addr = strtoull(endptr, &endptr, 0);
		if (*endptr != '('))
			ops->target.addr = addr;


Thanks,
Namhyung


> +	}
>  	goto find_target;
>  }
>  
>