https://gcc.gnu.org/g:5d24bf3afd1bea3e51b87fb7ff24c21e29913999
commit r14-9325-g5d24bf3afd1bea3e51b87fb7ff24c21e29913999
Author: Cupertino Miranda <cupertino.mira...@oracle.com>
Date: Thu Feb 29 10:56:13 2024 -0800
ctf: fix incorrect CTF for multi-dimensional array types
PR debug/114186
DWARF DIEs of type DW_TAG_subrange_type are linked together to represent
the information about the subsequent dimensions. The CTF processing was
so far working through them in the opposite (incorrect) order.
While fixing the issue, refactor the code a bit for readability.
co-authored-By: Indu Bhagat <indu.bha...@oracle.com>
gcc/
PR debug/114186
* dwarf2ctf.cc (gen_ctf_array_type): Invoke the ctf_add_array ()
in the correct order of the dimensions.
(gen_ctf_subrange_type): Refactor out handling of
DW_TAG_subrange_type DIE to here.
gcc/testsuite/
PR debug/114186
* gcc.dg/debug/ctf/ctf-array-6.c: Add test.
Diff:
---
gcc/dwarf2ctf.cc | 158 +++++++++++++--------------
gcc/testsuite/gcc.dg/debug/ctf/ctf-array-6.c | 14 +++
2 files changed, 89 insertions(+), 83 deletions(-)
diff --git a/gcc/dwarf2ctf.cc b/gcc/dwarf2ctf.cc
index dca86edfffa..77d6bf89689 100644
--- a/gcc/dwarf2ctf.cc
+++ b/gcc/dwarf2ctf.cc
@@ -349,105 +349,97 @@ gen_ctf_pointer_type (ctf_container_ref ctfc, dw_die_ref
ptr_type)
return ptr_type_id;
}
-/* Generate CTF for an array type. */
+/* Recursively generate CTF for array dimensions starting at DIE C (of type
+ DW_TAG_subrange_type) until DIE LAST (of type DW_TAG_subrange_type) is
+ reached. ARRAY_ELEMS_TYPE_ID is base type for the array. */
static ctf_id_t
-gen_ctf_array_type (ctf_container_ref ctfc, dw_die_ref array_type)
+gen_ctf_subrange_type (ctf_container_ref ctfc, ctf_id_t array_elems_type_id,
+ dw_die_ref c, dw_die_ref last)
{
- dw_die_ref c;
- ctf_id_t array_elems_type_id = CTF_NULL_TYPEID;
+ ctf_arinfo_t arinfo;
+ ctf_id_t array_node_type_id = CTF_NULL_TYPEID;
- int vector_type_p = get_AT_flag (array_type, DW_AT_GNU_vector);
- if (vector_type_p)
- return array_elems_type_id;
+ dw_attr_node *upper_bound_at;
+ dw_die_ref array_index_type;
+ uint32_t array_num_elements;
- dw_die_ref array_elems_type = ctf_get_AT_type (array_type);
+ if (dw_get_die_tag (c) == DW_TAG_subrange_type)
+ {
+ /* When DW_AT_upper_bound is used to specify the size of an
+ array in DWARF, it is usually an unsigned constant
+ specifying the upper bound index of the array. However,
+ for unsized arrays, such as foo[] or bar[0],
+ DW_AT_upper_bound is a signed integer constant
+ instead. */
+
+ upper_bound_at = get_AT (c, DW_AT_upper_bound);
+ if (upper_bound_at
+ && AT_class (upper_bound_at) == dw_val_class_unsigned_const)
+ /* This is the upper bound index. */
+ array_num_elements = get_AT_unsigned (c, DW_AT_upper_bound) + 1;
+ else if (get_AT (c, DW_AT_count))
+ array_num_elements = get_AT_unsigned (c, DW_AT_count);
+ else
+ {
+ /* This is a VLA of some kind. */
+ array_num_elements = 0;
+ }
+ }
+ else
+ gcc_unreachable ();
- /* First, register the type of the array elements if needed. */
- array_elems_type_id = gen_ctf_type (ctfc, array_elems_type);
+ /* Ok, mount and register the array type. Note how the array
+ type we register here is the type of the elements in
+ subsequent "dimensions", if there are any. */
+ arinfo.ctr_nelems = array_num_elements;
- /* DWARF array types pretend C supports multi-dimensional arrays.
- So for the type int[N][M], the array type DIE contains two
- subrange_type children, the first with upper bound N-1 and the
- second with upper bound M-1.
+ array_index_type = ctf_get_AT_type (c);
+ arinfo.ctr_index = gen_ctf_type (ctfc, array_index_type);
- CTF, on the other hand, just encodes each array type in its own
- array type CTF struct. Therefore we have to iterate on the
- children and create all the needed types. */
+ if (c == last)
+ arinfo.ctr_contents = array_elems_type_id;
+ else
+ arinfo.ctr_contents = gen_ctf_subrange_type (ctfc, array_elems_type_id,
+ dw_get_die_sib (c), last);
- c = dw_get_die_child (array_type);
- gcc_assert (c);
- do
- {
- ctf_arinfo_t arinfo;
- dw_die_ref array_index_type;
- uint32_t array_num_elements;
+ if (!ctf_type_exists (ctfc, c, &array_node_type_id))
+ array_node_type_id = ctf_add_array (ctfc, CTF_ADD_ROOT, &arinfo, c);
- c = dw_get_die_sib (c);
+ return array_node_type_id;
+}
- if (dw_get_die_tag (c) == DW_TAG_subrange_type)
- {
- dw_attr_node *upper_bound_at;
-
- array_index_type = ctf_get_AT_type (c);
-
- /* When DW_AT_upper_bound is used to specify the size of an
- array in DWARF, it is usually an unsigned constant
- specifying the upper bound index of the array. However,
- for unsized arrays, such as foo[] or bar[0],
- DW_AT_upper_bound is a signed integer constant
- instead. */
-
- upper_bound_at = get_AT (c, DW_AT_upper_bound);
- if (upper_bound_at
- && AT_class (upper_bound_at) == dw_val_class_unsigned_const)
- /* This is the upper bound index. */
- array_num_elements = get_AT_unsigned (c, DW_AT_upper_bound) + 1;
- else if (get_AT (c, DW_AT_count))
- array_num_elements = get_AT_unsigned (c, DW_AT_count);
- else
- {
- /* This is a VLA of some kind. */
- array_num_elements = 0;
- }
- }
- else if (dw_get_die_tag (c) == DW_TAG_enumeration_type)
- {
- array_index_type = 0;
- array_num_elements = 0;
- /* XXX writeme. */
- gcc_assert (1);
- }
- else
- gcc_unreachable ();
+/* Generate CTF for an ARRAY_TYPE. */
- /* Ok, mount and register the array type. Note how the array
- type we register here is the type of the elements in
- subsequent "dimensions", if there are any. */
+static ctf_id_t
+gen_ctf_array_type (ctf_container_ref ctfc,
+ dw_die_ref array_type)
+{
+ dw_die_ref first, last, array_elems_type;
+ ctf_id_t array_elems_type_id = CTF_NULL_TYPEID;
+ ctf_id_t array_type_id = CTF_NULL_TYPEID;
- arinfo.ctr_nelems = array_num_elements;
- if (array_index_type)
- arinfo.ctr_index = gen_ctf_type (ctfc, array_index_type);
- else
- arinfo.ctr_index = gen_ctf_type (ctfc, ctf_array_index_die);
+ int vector_type_p = get_AT_flag (array_type, DW_AT_GNU_vector);
+ if (vector_type_p)
+ return array_elems_type_id;
- arinfo.ctr_contents = array_elems_type_id;
- if (!ctf_type_exists (ctfc, c, &array_elems_type_id))
- array_elems_type_id = ctf_add_array (ctfc, CTF_ADD_ROOT, &arinfo,
- c);
- }
- while (c != dw_get_die_child (array_type));
+ /* Find the first and last array dimension DIEs. */
+ last = dw_get_die_child (array_type);
+ first = dw_get_die_sib (last);
-#if 0
/* Type de-duplication.
- Consult the ctfc_types hash again before adding the CTF array type because
- there can be cases where an array_type type may have been added by the
- gen_ctf_type call above. */
- if (!ctf_type_exists (ctfc, array_type, &type_id))
- type_id = ctf_add_array (ctfc, CTF_ADD_ROOT, &arinfo, array_type);
-#endif
-
- return array_elems_type_id;
+ Consult the ctfc_types before adding CTF type for the first dimension. */
+ if (!ctf_type_exists (ctfc, first, &array_type_id))
+ {
+ array_elems_type = ctf_get_AT_type (array_type);
+ /* First, register the type of the array elements if needed. */
+ array_elems_type_id = gen_ctf_type (ctfc, array_elems_type);
+
+ array_type_id = gen_ctf_subrange_type (ctfc, array_elems_type_id, first,
+ last);
+ }
+
+ return array_type_id;
}
/* Generate CTF for a typedef. */
diff --git a/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-6.c
b/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-6.c
new file mode 100644
index 00000000000..5564cb8865d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/debug/ctf/ctf-array-6.c
@@ -0,0 +1,14 @@
+/* CTF generation for multidimensional array. */
+
+/* { dg-do compile ) */
+/* { dg-options "-O0 -gctf -dA" } */
+
+/* { dg-final { scan-assembler-times "\[\t \]+0x2\[\t \]+\[^\n\]*cta_nelems" 1
} } */
+/* { dg-final { scan-assembler-times "\[\t \]+0x3\[\t \]+\[^\n\]*cta_nelems" 1
} } */
+/* { dg-final { scan-assembler-times "\[\t \]+0x4\[\t \]+\[^\n\]*cta_nelems" 1
} } */
+
+/* { dg-final { scan-assembler-times "\[\t \]+0x1\[\t
\]+\[^\n\]*cta_contents\[\\r\\n\]+\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*0x4\[\t
\]+\[^\n\]*cta_nelems" 1 } } */
+/* { dg-final { scan-assembler-times "\[\t \]+0x3\[\t
\]+\[^\n\]*cta_contents\[\\r\\n\]+\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*0x3\[\t
\]+\[^\n\]*cta_nelems" 1 } } */
+/* { dg-final { scan-assembler-times "\[\t \]+0x4\[\t
\]+\[^\n\]*cta_contents\[\\r\\n\]+\[^\\r\\n\]*\[\\r\\n\]+\[^\\r\\n\]*0x2\[\t
\]+\[^\n\]*cta_nelems" 1 } } */
+
+int a[2][3][4];
