PR debug/112768 - btf: fix asm comment output for BTF_KIND_FUNC* kinds
The patch adds a small function to abstract out the detail and return
the name of the type. The patch also fixes the issue of BTF_KIND_FUNC
appearing in the comments with a 'null' string.
For btf-function-6.c testcase, after the patch:
.long 0 # TYPE 2 BTF_KIND_FUNC_PROTO ''
.long 0xd000002 # btt_info: kind=13, kflag=0, vlen=2
.long 0x1 # btt_type: (BTF_KIND_INT 'int')
.long 0 # farg_name
.long 0x1 # farg_type: (BTF_KIND_INT 'int')
.long 0 # farg_name
.long 0x1 # farg_type: (BTF_KIND_INT 'int')
.long 0 # TYPE 3 BTF_KIND_FUNC_PROTO ''
.long 0xd000001 # btt_info: kind=13, kflag=0, vlen=1
.long 0x1 # btt_type: (BTF_KIND_INT 'int')
.long 0x68 # farg_name
.long 0x1 # farg_type: (BTF_KIND_INT 'int')
.long 0x5 # TYPE 4 BTF_KIND_FUNC 'extfunc'
.long 0xc000002 # btt_info: kind=12, kflag=0, linkage=2
.long 0x2 # btt_type: (BTF_KIND_FUNC_PROTO '')
.long 0xd # TYPE 5 BTF_KIND_FUNC 'foo'
.long 0xc000001 # btt_info: kind=12, kflag=0, linkage=1
.long 0x3 # btt_type: (BTF_KIND_FUNC_PROTO '')
gcc/ChangeLog:
PR debug/112768
* btfout.cc (get_btf_type_name): New definition.
(btf_collect_datasec): Update dtd_name to the original type name
string.
(btf_asm_type_ref): Use the new get_btf_type_name function
instead.
(btf_asm_type): Likewise.
(btf_asm_func_type): Likewise.
gcc/testsuite/ChangeLog:
PR debug/112768
* gcc.dg/debug/btf/btf-function-6.c: Empty string expected with
BTF_KIND_FUNC_PROTO.
Testing notes:
- bootstrapped and reg tested on x86_64
- No regressions in btf.exp on BPF target
---
gcc/btfout.cc | 22 +++++++++++++++----
.../gcc.dg/debug/btf/btf-function-6.c | 4 ++--
2 files changed, 20 insertions(+), 6 deletions(-)
diff --git a/gcc/btfout.cc b/gcc/btfout.cc
index 5f2e99ce472..1c25404b2c0 100644
--- a/gcc/btfout.cc
+++ b/gcc/btfout.cc
@@ -158,6 +158,19 @@ get_btf_kind (uint32_t ctf_kind)
return BTF_KIND_UNKN;
}
+/* Some BTF types, like BTF_KIND_FUNC_PROTO, are anonymous. The machinery
+ in btfout to emit BTF, may reset dtd_data->ctti_name, but does not update
+ the name in the ctf_dtdef_ref type object (deliberate choice). This
+ interface helps abstract out that state of affairs, while giving access to
+ the name of the type as intended. */
+
+static const char *
+get_btf_type_name (ctf_dtdef_ref dtd)
+{
+ const char *anon = "";
+ return (dtd->dtd_data.ctti_name) ? dtd->dtd_name : anon;
+}
+
/* Helper routines to map between 'relative' and 'absolute' IDs.
In BTF all records (including variables) are output in one long list, and
all
@@ -425,6 +438,7 @@ btf_collect_datasec (ctf_container_ref ctfc)
func_dtd->dtd_data = dtd->dtd_data;
func_dtd->dtd_data.ctti_type = dtd->dtd_type;
func_dtd->linkage = dtd->linkage;
+ func_dtd->dtd_name = dtd->dtd_name;
func_dtd->dtd_type = num_types_added + num_types_created;
/* Only the BTF_KIND_FUNC type actually references the name. The
@@ -722,7 +736,7 @@ btf_asm_type_ref (const char *prefix, ctf_container_ref
ctfc, ctf_id_t ref_id)
size_t func_id = btf_relative_func_id (ref_id);
ctf_dtdef_ref ref_type = (*funcs)[func_id];
dw2_asm_output_data (4, ref_id, "%s: (BTF_KIND_FUNC '%s')",
- prefix, ref_type->dtd_name);
+ prefix, get_btf_type_name (ref_type));
}
else
{
@@ -733,7 +747,7 @@ btf_asm_type_ref (const char *prefix, ctf_container_ref
ctfc, ctf_id_t ref_id)
dw2_asm_output_data (4, ref_id, "%s: (BTF_KIND_%s '%s')",
prefix, btf_kind_name (ref_kind),
- ref_type->dtd_name);
+ get_btf_type_name (ref_type));
}
}
@@ -809,7 +823,7 @@ btf_asm_type (ctf_container_ref ctfc, ctf_dtdef_ref dtd)
dw2_asm_output_data (4, dtd->dtd_data.ctti_name,
"TYPE %" PRIu64 " BTF_KIND_%s '%s'",
get_btf_id (dtd->dtd_type), btf_kind_name (btf_kind),
- dtd->dtd_name);
+ get_btf_type_name (dtd));
dw2_asm_output_data (4, BTF_TYPE_INFO (btf_kind, btf_kflag, btf_vlen),
"btt_info: kind=%u, kflag=%u, vlen=%u",
btf_kind, btf_kflag, btf_vlen);
@@ -950,7 +964,7 @@ btf_asm_func_type (ctf_container_ref ctfc, ctf_dtdef_ref
dtd, ctf_id_t id)
ctf_id_t ref_id = dtd->dtd_data.ctti_type;
dw2_asm_output_data (4, dtd->dtd_data.ctti_name,
"TYPE %" PRIu64 " BTF_KIND_FUNC '%s'",
- btf_absolute_func_id (id), dtd->dtd_name);
+ btf_absolute_func_id (id), get_btf_type_name (dtd));
dw2_asm_output_data (4, BTF_TYPE_INFO (BTF_KIND_FUNC, 0, dtd->linkage),
"btt_info: kind=%u, kflag=%u, linkage=%u",
BTF_KIND_FUNC, 0, dtd->linkage);
diff --git a/gcc/testsuite/gcc.dg/debug/btf/btf-function-6.c
b/gcc/testsuite/gcc.dg/debug/btf/btf-function-6.c
index e014d9990a9..802bc6d1c74 100644
--- a/gcc/testsuite/gcc.dg/debug/btf/btf-function-6.c
+++ b/gcc/testsuite/gcc.dg/debug/btf/btf-function-6.c
@@ -6,8 +6,8 @@
/* { dg-do compile } */
/* { dg-options "-O0 -gbtf -dA" } */
-/* { dg-final { scan-assembler-times "
BTF_KIND_FUNC\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*linkage=2\[\\r\\n\]+\[^\\r\\n\]*\\(BTF_KIND_FUNC_PROTO
'extfunc'" 1 } } */
-/* { dg-final { scan-assembler-times "
BTF_KIND_FUNC\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*linkage=1\[\\r\\n\]+\[^\\r\\n\]*\\(BTF_KIND_FUNC_PROTO
'foo'" 1 } } */
+/* { dg-final { scan-assembler-times "
BTF_KIND_FUNC\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*linkage=2\[\\r\\n\]+\[^\\r\\n\]*\\(BTF_KIND_FUNC_PROTO
''" 1 } } */
+/* { dg-final { scan-assembler-times "
BTF_KIND_FUNC\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*linkage=1\[\\r\\n\]+\[^\\r\\n\]*\\(BTF_KIND_FUNC_PROTO
''" 1 } } */
extern int extfunc(int a, int b);
--
2.41.0
