lkml.org 
[lkml]   [2018]   [Aug]   [27]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH] Properly interpret indirect call in perf annotate.
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;
> }
>
>

\
 
 \ /
  Last update: 2018-08-27 12:38    [W:0.070 / U:4.896 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site