On Wed, 11 Oct 2023 20:50:29 -0700
Namhyung Kim <namhyung@xxxxxxxxxx> wrote:
> The die_get_scopes() would return the number of enclosing DIEs for the
> given address and it fills an array of DIEs like dwarf_getscopes().
> But it doesn't follow the abstract origin of inlined functions as we
> want information of the concrete instance. This is needed to check the
> location of parameters and local variables properly. Users can check
> the origin separately if needed.
This looks good to me.
Acked-by: Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
Thanks
>
> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Signed-off-by: Namhyung Kim <namhyung@xxxxxxxxxx>
> ---
> tools/perf/util/dwarf-aux.c | 53 +++++++++++++++++++++++++++++++++++++
> tools/perf/util/dwarf-aux.h | 3 +++
> 2 files changed, 56 insertions(+)
>
> diff --git a/tools/perf/util/dwarf-aux.c b/tools/perf/util/dwarf-aux.c
> index adef2635587d..10aa32334d6f 100644
> --- a/tools/perf/util/dwarf-aux.c
> +++ b/tools/perf/util/dwarf-aux.c
> @@ -1425,3 +1425,56 @@ void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die,
>
> *entrypc = postprologue_addr;
> }
> +
> +/* Internal parameters for __die_find_scope_cb() */
> +struct find_scope_data {
> + /* Target instruction address */
> + Dwarf_Addr pc;
> + /* Number of scopes found [output] */
> + int nr;
> + /* Array of scopes found, 0 for the outermost one. [output] */
> + Dwarf_Die *scopes;
> +};
> +
> +static int __die_find_scope_cb(Dwarf_Die *die_mem, void *arg)
> +{
> + struct find_scope_data *data = arg;
> +
> + if (dwarf_haspc(die_mem, data->pc)) {
> + Dwarf_Die *tmp;
> +
> + tmp = realloc(data->scopes, (data->nr + 1) * sizeof(*tmp));
> + if (tmp == NULL)
> + return DIE_FIND_CB_END;
> +
> + memcpy(tmp + data->nr, die_mem, sizeof(*die_mem));
> + data->scopes = tmp;
> + data->nr++;
> + return DIE_FIND_CB_CHILD;
> + }
> + return DIE_FIND_CB_SIBLING;
> +}
> +
> +/**
> + * die_get_scopes - Return a list of scopes including the address
> + * @cu_die: a compile unit DIE
> + * @pc: the address to find
> + * @scopes: the array of DIEs for scopes (result)
> + *
> + * This function does the same as the dwarf_getscopes() but doesn't follow
> + * the origins of inlined functions. It returns the number of scopes saved
> + * in the @scopes argument. The outer scope will be saved first (index 0) and
> + * the last one is the innermost scope at the @pc.
> + */
> +int die_get_scopes(Dwarf_Die *cu_die, Dwarf_Addr pc, Dwarf_Die **scopes)
> +{
> + struct find_scope_data data = {
> + .pc = pc,
> + };
> + Dwarf_Die die_mem;
> +
> + die_find_child(cu_die, __die_find_scope_cb, &data, &die_mem);
> +
> + *scopes = data.scopes;
> + return data.nr;
> +}
> diff --git a/tools/perf/util/dwarf-aux.h b/tools/perf/util/dwarf-aux.h
> index 4f5d0211ee4f..f9d765f80fb0 100644
> --- a/tools/perf/util/dwarf-aux.h
> +++ b/tools/perf/util/dwarf-aux.h
> @@ -129,6 +129,9 @@ bool die_is_optimized_target(Dwarf_Die *cu_die);
> void die_skip_prologue(Dwarf_Die *sp_die, Dwarf_Die *cu_die,
> Dwarf_Addr *entrypc);
>
> +/* Get the list of including scopes */
> +int die_get_scopes(Dwarf_Die *cu_die, Dwarf_Addr pc, Dwarf_Die **scopes);
> +
> #ifdef HAVE_DWARF_GETLOCATIONS_SUPPORT
>
> /* Get byte offset range of given variable DIE */
> --
> 2.42.0.655.g421f12c284-goog
>
--
Masami Hiramatsu (Google) <mhiramat@xxxxxxxxxx>
|