Many DW_AT_subroutine DIEs do not have address info associated
directly; some use DW_AT_ranges, and some have address info
stored with the associated abstract origin. Use these information
sources to improve address retrieval for "struct function"
representations.
Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
---
dwarf_loader.c | 29 +++++++++++++++++++++++++----
dwarves.h | 3 ++-
2 files changed, 27 insertions(+), 5 deletions(-)
diff --git a/dwarf_loader.c b/dwarf_loader.c
index e1ba7bc..d46e82a 100644
--- a/dwarf_loader.c
+++ b/dwarf_loader.c
@@ -1519,6 +1519,17 @@ static struct function *function__new(Dwarf_Die *die, struct cu *cu, struct conf
func->vtable_entry = -1;
if (dwarf_hasattr(die, DW_AT_vtable_elem_location))
func->vtable_entry = attr_offset(die, DW_AT_vtable_elem_location);
+ /* some functions will have entry address in the start address
+ * in DW_AT_ranges.
+ */
+ if (dwarf_hasattr(die, DW_AT_ranges)) {
+ Dwarf_Addr base, start, high_pc;
+ ptrdiff_t offset = 0;
+
+ dwarf_ranges(die, offset, &base, &start, &high_pc);
+ if (start)
+ func->addr = (uint64_t)start;
+ }
func->cu_total_size_inline_expansions = 0;
func->cu_total_nr_inline_expansions = 0;
func->priv = NULL;
@@ -2805,7 +2816,7 @@ static int tag__recode_dwarf_type(struct tag *tag, struct cu *cu)
case DW_TAG_subprogram: {
struct function *fn = tag__function(tag);
- if (fn->name == 0) {
+ if (fn->name == 0 || function__addr(fn) == 0) {
if (dtag->abstract_origin == 0 &&
dtag->specification == 0) {
/*
@@ -2818,9 +2829,19 @@ static int tag__recode_dwarf_type(struct tag *tag, struct cu *cu)
dtype = dwarf_cu__find_tag_by_ref(cu->priv, dtag, abstract_origin);
if (dtype == NULL)
dtype = dwarf_cu__find_tag_by_ref(cu->priv, dtag, specification);
- if (dtype != NULL)
- fn->name = tag__function(dtag__tag(dtype))->name;
- else {
+ if (dtype != NULL) {
+ struct function *dfn = tag__function(dtag__tag(dtype));
+ if (fn->name == 0)
+ fn->name = dfn->name;
+ /* share function address info between tag and
+ * abstract origin.
+ */
+ if (!function__addr(fn))
+ fn->addr = function__addr(dfn);
+ else if (!function__addr(dfn))
+ dfn->addr = function__addr(fn);
+ }
+ if (fn->name == 0) {
fprintf(stderr,
"%s: couldn't find name for "
"function %#llx, abstract_origin=%#llx,"
diff --git a/dwarves.h b/dwarves.h
index 36c6898..847e13d 100644
--- a/dwarves.h
+++ b/dwarves.h
@@ -1081,6 +1081,7 @@ struct function {
const char *name;
const char *linkage_name;
const char *alias; /* name.isra.0 */
+ uint64_t addr;
uint32_t cu_total_size_inline_expansions;
uint16_t cu_total_nr_inline_expansions;
uint8_t inlined:2;
@@ -1146,7 +1147,7 @@ const char *function__prototype_conf(const struct function *func,
static __pure inline uint64_t function__addr(const struct function *func)
{
- return func->lexblock.ip.addr;
+ return func->lexblock.ip.addr ?: func->addr;
}
static __pure inline uint32_t function__size(const struct function *func)
--
2.39.3
