Commit 4a32a972 authored by Namhyung Kim's avatar Namhyung Kim Committed by Arnaldo Carvalho de Melo
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perf annotate-data: Prefer struct/union over base type 



Sometimes a compound type can have a single field and the size is the
same as the base type.  But it's still preferred as struct or union
could carry more information than the base type.

Also put a slight priority on the typedef for the same reason.

Signed-off-by: default avatarNamhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20240821065408.285548-2-namhyung@kernel.org


Signed-off-by: default avatarArnaldo Carvalho de Melo <acme@redhat.com>
parent 922ec313

tools/perf/util/annotate-data.c

+19 −1
Original line number Diff line number Diff line
@@ -404,6 +404,13 @@ static bool is_pointer_type(Dwarf_Die *type_die) 
	return tag == DW_TAG_pointer_type || tag == DW_TAG_array_type;

}



static bool is_compound_type(Dwarf_Die *type_die)

{

	int tag = dwarf_tag(type_die);



	return tag == DW_TAG_structure_type || tag == DW_TAG_union_type;

}



/* returns if Type B has better information than Type A */

static bool is_better_type(Dwarf_Die *type_a, Dwarf_Die *type_b)

{
@@ -433,7 +440,18 @@ static bool is_better_type(Dwarf_Die *type_a, Dwarf_Die *type_b) 
	    dwarf_aggregate_size(type_b, &size_b) < 0)

		return false;



	if (size_a != size_b)

		return size_a < size_b;



	/* struct or union is preferred */

	if (is_compound_type(type_a) != is_compound_type(type_b))

		return is_compound_type(type_b);



	/* typedef is preferred */

	if (dwarf_tag(type_b) == DW_TAG_typedef)

		return true;



	return false;

}



/* The type info will be saved in @type_die */