[PATCH v4 08/19] gendwarfksyms: Expand array_type

Sami Tolvanen
2024-10-08T18:38:52Z

Add support for expanding DW_TAG_array_type, and the subrange type
indicating array size.

Example source code:

const char *s[34];

Output with --dump-dies:

variable array_type[34] {
pointer_type {
const_type {
base_type char byte_size(1) encoding(6)
}
} byte_size(8)
}

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Acked-by: Neal Gompa <neal@gompa.dev>
Reviewed-by: Petr Pavlu <petr.pavlu@suse.com>
---
scripts/gendwarfksyms/dwarf.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)

diff --git a/scripts/gendwarfksyms/dwarf.c b/scripts/gendwarfksyms/dwarf.c
index 7e6b477d7c12..ade9b3b7b119 100644
--- a/scripts/gendwarfksyms/dwarf.c
+++ b/scripts/gendwarfksyms/dwarf.c
@@ -219,6 +219,7 @@ DEFINE_PROCESS_UDATA_ATTRIBUTE(encoding)
}

DEFINE_MATCH(formal_parameter)
+DEFINE_MATCH(subrange)

bool match_all(Dwarf_Die *die)
{
@@ -341,6 +342,33 @@ DEFINE_PROCESS_TYPE(shared)
DEFINE_PROCESS_TYPE(volatile)
DEFINE_PROCESS_TYPE(typedef)

+static void process_subrange_type(struct state *state, struct die *cache,
+ Dwarf_Die *die)
+{
+ Dwarf_Word count = 0;
+
+ if (get_udata_attr(die, DW_AT_count, &count))
+ process_fmt(cache, "[%" PRIu64 "]", count);
+ else if (get_udata_attr(die, DW_AT_upper_bound, &count))
+ process_fmt(cache, "[%" PRIu64 "]", count + 1);
+ else
+ process(cache, "[]");
+}
+
+static void process_array_type(struct state *state, struct die *cache,
+ Dwarf_Die *die)
+{
+ process(cache, "array_type");
+ /* Array size */
+ check(process_die_container(state, cache, die, process_type,
+ match_subrange_type));
+ process(cache, " {");
+ process_linebreak(cache, 1);
+ process_type_attr(state, cache, die);
+ process_linebreak(cache, -1);
+ process(cache, "}");
+}
+
static void __process_subroutine_type(struct state *state, struct die *cache,
Dwarf_Die *die, const char *type)
{
@@ -436,7 +464,9 @@ static int process_type(struct state *state, struct die *parent, Dwarf_Die *die)
PROCESS_TYPE(volatile)
/* Subtypes */
PROCESS_TYPE(formal_parameter)
+ PROCESS_TYPE(subrange)
/* Other types */
+ PROCESS_TYPE(array)
PROCESS_TYPE(base)
PROCESS_TYPE(subroutine)
PROCESS_TYPE(typedef)