https://gcc.gnu.org/g:310fd68c6cb62b69ddd98c61aab8cb9db242b6a4
commit r15-3277-g310fd68c6cb62b69ddd98c61aab8cb9db242b6a4
Author: Mark Harmstone <m...@harmstone.com>
Date: Mon Aug 26 21:19:51 2024 +0100
Handle scoping in CodeView LF_FUNC_ID types
If a function is in a namespace, create an LF_STRING_ID type for the
name of its parent, and record this in the LF_FUNC_ID type we create
for the function.
gcc/
* dwarf2codeview.cc (enum cf_leaf_type): Add LF_STRING_ID.
(struct codeview_custom_type): Add lf_string_id to union.
(struct string_id_hasher): New type.
(string_id_htab): New global variable.
(write_lf_string_id): New function.
(write_custom_types): Call write_lf_string_id.
(codeview_debug_finish): Free string_id_htab.
(add_string_id): New function.
(get_scope_string_id): New function.
(add_function): Call get_scope_string_id and set scope.
Diff:
---
gcc/dwarf2codeview.cc | 139 +++++++++++++++++++++++++++++++++++++++++++++++++-
1 file changed, 137 insertions(+), 2 deletions(-)
diff --git a/gcc/dwarf2codeview.cc b/gcc/dwarf2codeview.cc
index b71c592b70c8..2535777d4cbd 100644
--- a/gcc/dwarf2codeview.cc
+++ b/gcc/dwarf2codeview.cc
@@ -107,6 +107,7 @@ enum cv_leaf_type {
LF_ENUM = 0x1507,
LF_MEMBER = 0x150d,
LF_FUNC_ID = 0x1601,
+ LF_STRING_ID = 0x1605,
LF_CHAR = 0x8000,
LF_SHORT = 0x8001,
LF_USHORT = 0x8002,
@@ -1293,6 +1294,11 @@ struct codeview_custom_type
uint32_t function_type;
char *name;
} lf_func_id;
+ struct
+ {
+ uint32_t substring;
+ char *string;
+ } lf_string_id;
};
};
@@ -1302,6 +1308,21 @@ struct codeview_deferred_type
dw_die_ref type;
};
+struct string_id_hasher : nofree_ptr_hash <struct codeview_custom_type>
+{
+ typedef const char *compare_type;
+
+ static hashval_t hash (const codeview_custom_type *x)
+ {
+ return htab_hash_string (x->lf_string_id.string);
+ }
+
+ static bool equal (const codeview_custom_type *x, const char *y)
+ {
+ return !strcmp (x->lf_string_id.string, y);
+ }
+};
+
static unsigned int line_label_num;
static unsigned int func_label_num;
static unsigned int sym_label_num;
@@ -1317,6 +1338,7 @@ static codeview_symbol *sym, *last_sym;
static hash_table<die_hasher> *types_htab;
static codeview_custom_type *custom_types, *last_custom_type;
static codeview_deferred_type *deferred_types, *last_deferred_type;
+static hash_table<string_id_hasher> *string_id_htab;
static uint32_t get_type_num (dw_die_ref type, bool in_struct, bool
no_fwd_ref);
@@ -4089,6 +4111,50 @@ write_lf_func_id (codeview_custom_type *t)
asm_fprintf (asm_out_file, "%LLcv_type%x_end:\n", t->num);
}
+/* Write an LF_STRING_ID type, which provides a deduplicated string that other
+ types can reference. */
+
+static void
+write_lf_string_id (codeview_custom_type *t)
+{
+ size_t string_len;
+
+ /* This is lf_string_id in binutils and lfStringId in Microsoft's cvinfo.h:
+
+ struct lf_string_id
+ {
+ uint16_t size;
+ uint16_t kind;
+ uint32_t substring;
+ char string[];
+ } ATTRIBUTE_PACKED;
+ */
+
+ fputs (integer_asm_op (2, false), asm_out_file);
+ asm_fprintf (asm_out_file, "%LLcv_type%x_end - %LLcv_type%x_start\n",
+ t->num, t->num);
+
+ asm_fprintf (asm_out_file, "%LLcv_type%x_start:\n", t->num);
+
+ fputs (integer_asm_op (2, false), asm_out_file);
+ fprint_whex (asm_out_file, t->kind);
+ putc ('\n', asm_out_file);
+
+ fputs (integer_asm_op (4, false), asm_out_file);
+ fprint_whex (asm_out_file, t->lf_string_id.substring);
+ putc ('\n', asm_out_file);
+
+ string_len = strlen (t->lf_string_id.string) + 1;
+
+ ASM_OUTPUT_ASCII (asm_out_file, t->lf_string_id.string, string_len);
+
+ write_cv_padding (4 - (string_len % 4));
+
+ free (t->lf_string_id.string);
+
+ asm_fprintf (asm_out_file, "%LLcv_type%x_end:\n", t->num);
+}
+
/* Write the .debug$T section, which contains all of our custom type
definitions. */
@@ -4152,6 +4218,10 @@ write_custom_types (void)
write_lf_func_id (custom_types);
break;
+ case LF_STRING_ID:
+ write_lf_string_id (custom_types);
+ break;
+
default:
break;
}
@@ -4182,6 +4252,9 @@ codeview_debug_finish (void)
if (types_htab)
delete types_htab;
+
+ if (string_id_htab)
+ delete string_id_htab;
}
/* Translate a DWARF base type (DW_TAG_base_type) into its CodeView
@@ -5461,6 +5534,67 @@ add_variable (dw_die_ref die)
last_sym = s;
}
+/* Return the type number of the LF_STRING_ID entry corresponding to the given
+ string, creating a new one if necessary. */
+
+static uint32_t
+add_string_id (const char *s)
+{
+ codeview_custom_type **slot;
+ codeview_custom_type *ct;
+
+ if (!string_id_htab)
+ string_id_htab = new hash_table<string_id_hasher> (10);
+
+ slot = string_id_htab->find_slot_with_hash (s, htab_hash_string (s),
+ INSERT);
+ if (*slot)
+ return (*slot)->num;
+
+ ct = (codeview_custom_type *) xmalloc (sizeof (codeview_custom_type));
+
+ ct->next = NULL;
+ ct->kind = LF_STRING_ID;
+ ct->lf_string_id.substring = 0;
+ ct->lf_string_id.string = xstrdup (s);
+
+ add_custom_type (ct);
+
+ *slot = ct;
+
+ return ct->num;
+}
+
+/* Return the type number of the LF_STRING_ID corresponding to the given DIE's
+ parent, or 0 if it is in the global scope. */
+
+static uint32_t
+get_scope_string_id (dw_die_ref die)
+{
+ dw_die_ref decl = get_AT_ref (die, DW_AT_specification);
+ char *name;
+ uint32_t ret;
+
+ if (decl)
+ die = decl;
+
+ die = dw_get_die_parent (die);
+ if (!die)
+ return 0;
+
+ if (dw_get_die_tag (die) == DW_TAG_compile_unit)
+ return 0;
+
+ name = get_name (die);
+ if (!name)
+ return 0;
+
+ ret = add_string_id (name);
+ free (name);
+
+ return ret;
+}
+
/* Process a DW_TAG_subprogram DIE, and add an S_GPROC32_ID or S_LPROC32_ID
symbol for this. */
@@ -5469,7 +5603,7 @@ add_function (dw_die_ref die)
{
codeview_custom_type *ct;
const char *name = get_AT_string (die, DW_AT_name);
- uint32_t function_type, func_id_type;
+ uint32_t function_type, func_id_type, scope_type;
codeview_symbol *s;
if (!name)
@@ -5478,12 +5612,13 @@ add_function (dw_die_ref die)
/* Add an LF_FUNC_ID type for this function. */
function_type = get_type_num_subroutine_type (die, false);
+ scope_type = get_scope_string_id (die);
ct = (codeview_custom_type *) xmalloc (sizeof (codeview_custom_type));
ct->next = NULL;
ct->kind = LF_FUNC_ID;
- ct->lf_func_id.parent_scope = 0;
+ ct->lf_func_id.parent_scope = scope_type;
ct->lf_func_id.function_type = function_type;
ct->lf_func_id.name = xstrdup (name);
