diff options
Diffstat (limited to 'gdb/gnu-v3-abi.c')
| -rw-r--r-- | gdb/gnu-v3-abi.c | 158 |
1 files changed, 158 insertions, 0 deletions
diff --git a/gdb/gnu-v3-abi.c b/gdb/gnu-v3-abi.c index b3585a6..7649a48 100644 --- a/gdb/gnu-v3-abi.c +++ b/gdb/gnu-v3-abi.c @@ -34,6 +34,12 @@ static struct cp_abi_ops gnu_v3_abi_ops; +/* A gdbarch key for std::type_info, in the event that it can't be + found in the debug info. */ + +static struct gdbarch_data *std_type_info_gdbarch_data; + + static int gnuv3_is_vtable_name (const char *name) { @@ -984,6 +990,154 @@ gnuv3_print_vtable (struct value *value) do_cleanups (cleanup); } +/* Return a GDB type representing `struct std::type_info', laid out + appropriately for ARCH. + + We use this function as the gdbarch per-architecture data + initialization function. */ + +static void * +build_std_type_info_type (struct gdbarch *arch) +{ + struct type *t; + struct field *field_list, *field; + int offset; + struct type *void_ptr_type + = builtin_type (arch)->builtin_data_ptr; + struct type *char_type + = builtin_type (arch)->builtin_char; + struct type *char_ptr_type + = make_pointer_type (make_cv_type (1, 0, char_type, NULL), NULL); + + field_list = xmalloc (sizeof (struct field [2])); + memset (field_list, 0, sizeof (struct field [2])); + field = &field_list[0]; + offset = 0; + + /* The vtable. */ + FIELD_NAME (*field) = "_vptr.type_info"; + FIELD_TYPE (*field) = void_ptr_type; + SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); + offset += TYPE_LENGTH (FIELD_TYPE (*field)); + field++; + + /* The name. */ + FIELD_NAME (*field) = "__name"; + FIELD_TYPE (*field) = char_ptr_type; + SET_FIELD_BITPOS (*field, offset * TARGET_CHAR_BIT); + offset += TYPE_LENGTH (FIELD_TYPE (*field)); + field++; + + gdb_assert (field == (field_list + 2)); + + t = arch_type (arch, TYPE_CODE_STRUCT, offset, NULL); + TYPE_NFIELDS (t) = field - field_list; + TYPE_FIELDS (t) = field_list; + TYPE_TAG_NAME (t) = "gdb_gnu_v3_type_info"; + INIT_CPLUS_SPECIFIC (t); + + return t; +} + +/* Implement the 'get_typeid_type' method. */ + +static struct type * +gnuv3_get_typeid_type (struct gdbarch *gdbarch) +{ + struct symbol *typeinfo; + struct type *typeinfo_type; + + typeinfo = lookup_symbol ("std::type_info", NULL, STRUCT_DOMAIN, NULL); + if (typeinfo == NULL) + typeinfo_type = gdbarch_data (gdbarch, std_type_info_gdbarch_data); + else + typeinfo_type = SYMBOL_TYPE (typeinfo); + + return typeinfo_type; +} + +/* Implement the 'get_typeid' method. */ + +static struct value * +gnuv3_get_typeid (struct value *value) +{ + struct type *typeinfo_type; + struct type *type; + struct gdbarch *gdbarch; + struct cleanup *cleanup; + struct value *result; + char *typename, *canonical; + + /* We have to handle values a bit trickily here, to allow this code + to work properly with non_lvalue values that are really just + disguised types. */ + if (value_lval_const (value) == lval_memory) + value = coerce_ref (value); + + type = check_typedef (value_type (value)); + + /* In the non_lvalue case, a reference might have slipped through + here. */ + if (TYPE_CODE (type) == TYPE_CODE_REF) + type = check_typedef (TYPE_TARGET_TYPE (type)); + + /* Ignore top-level cv-qualifiers. */ + type = make_cv_type (0, 0, type, NULL); + gdbarch = get_type_arch (type); + + typename = type_to_string (type); + if (typename == NULL) + error (_("cannot find typeinfo for unnamed type")); + cleanup = make_cleanup (xfree, typename); + + /* We need to canonicalize the type name here, because we do lookups + using the demangled name, and so we must match the format it + uses. E.g., GDB tends to use "const char *" as a type name, but + the demangler uses "char const *". */ + canonical = cp_canonicalize_string (typename); + if (canonical != NULL) + { + make_cleanup (xfree, canonical); + typename = canonical; + } + + typeinfo_type = gnuv3_get_typeid_type (gdbarch); + + /* We check for lval_memory because in the "typeid (type-id)" case, + the type is passed via a not_lval value object. */ + if (TYPE_CODE (type) == TYPE_CODE_CLASS + && value_lval_const (value) == lval_memory + && gnuv3_dynamic_class (type)) + { + struct value *vtable, *typeinfo_value; + CORE_ADDR address = value_address (value) + value_embedded_offset (value); + + vtable = gnuv3_get_vtable (gdbarch, type, address); + if (vtable == NULL) + error (_("cannot find typeinfo for object of type '%s'"), typename); + typeinfo_value = value_field (vtable, vtable_field_type_info); + result = value_ind (value_cast (make_pointer_type (typeinfo_type, NULL), + typeinfo_value)); + } + else + { + char *sym_name; + struct minimal_symbol *minsym; + + sym_name = concat ("typeinfo for ", typename, (char *) NULL); + make_cleanup (xfree, sym_name); + minsym = lookup_minimal_symbol (sym_name, NULL, NULL); + + if (minsym == NULL) + error (_("could not find typeinfo symbol for '%s'"), typename); + + result = value_at_lazy (typeinfo_type, SYMBOL_VALUE_ADDRESS (minsym)); + } + + do_cleanups (cleanup); + return result; +} + /* Determine if we are currently in a C++ thunk. If so, get the address of the routine we are thunking to and continue to there instead. */ @@ -1116,6 +1270,8 @@ init_gnuv3_ops (void) { vtable_type_gdbarch_data = gdbarch_data_register_post_init (build_gdb_vtable_type); + std_type_info_gdbarch_data + = gdbarch_data_register_post_init (build_std_type_info_type); gnu_v3_abi_ops.shortname = "gnu-v3"; gnu_v3_abi_ops.longname = "GNU G++ Version 3 ABI"; @@ -1134,6 +1290,8 @@ init_gnuv3_ops (void) gnu_v3_abi_ops.make_method_ptr = gnuv3_make_method_ptr; gnu_v3_abi_ops.method_ptr_to_value = gnuv3_method_ptr_to_value; gnu_v3_abi_ops.print_vtable = gnuv3_print_vtable; + gnu_v3_abi_ops.get_typeid = gnuv3_get_typeid; + gnu_v3_abi_ops.get_typeid_type = gnuv3_get_typeid_type; gnu_v3_abi_ops.skip_trampoline = gnuv3_skip_trampoline; gnu_v3_abi_ops.pass_by_reference = gnuv3_pass_by_reference; } |