1 /* Low-level DWARF 2 reading code
3 Copyright (C) 1994-2020 Free Software Foundation, Inc.
5 Adapted by Gary Funck (gary@intrepid.com), Intrepid Technology,
6 Inc. with support from Florida State University (under contract
7 with the Ada Joint Program Office), and Silicon Graphics, Inc.
8 Initial contribution by Brent Benson, Harris Computer Systems, Inc.,
9 based on Fred Fish's (Cygnus Support) implementation of DWARF 1
12 This file is part of GDB.
14 This program is free software; you can redistribute it and/or modify
15 it under the terms of the GNU General Public License as published by
16 the Free Software Foundation; either version 3 of the License, or
17 (at your option) any later version.
19 This program is distributed in the hope that it will be useful,
20 but WITHOUT ANY WARRANTY; without even the implied warranty of
21 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 GNU General Public License for more details.
24 You should have received a copy of the GNU General Public License
25 along with this program. If not, see <http://www.gnu.org/licenses/>. */
27 #ifndef GDB_DWARF2_COMP_UNIT_H
28 #define GDB_DWARF2_COMP_UNIT_H
32 /* The data in a compilation unit header, after target2host
33 translation, looks like this. */
38 unsigned char addr_size
;
39 unsigned char signed_addr_p
;
40 sect_offset abbrev_sect_off
;
42 /* Size of file offsets; either 4 or 8. */
43 unsigned int offset_size
;
45 /* Size of the length field; either 4 or 12. */
46 unsigned int initial_length_size
;
48 enum dwarf_unit_type unit_type
;
50 /* Offset to the first byte of this compilation unit header in the
51 .debug_info section, for resolving relative reference dies. */
54 /* Offset to first die in this cu from the start of the cu.
55 This will be the first byte following the compilation unit header. */
56 cu_offset first_die_cu_offset
;
59 /* 64-bit signature of this unit. For type units, it denotes the signature of
60 the type (DW_UT_type in DWARF 4, additionally DW_UT_split_type in DWARF 5).
61 Also used in DWARF 5, to denote the dwo id when the unit type is
62 DW_UT_skeleton or DW_UT_split_compile. */
65 /* For types, offset in the type's DIE of the type defined by this TU. */
66 cu_offset type_cu_offset_in_tu
;
68 /* Return the total length of the CU described by this header. */
69 unsigned int get_length () const
71 return initial_length_size
+ length
;
74 /* Return TRUE if OFF is within this CU. */
75 bool offset_in_cu_p (sect_offset off
) const
77 sect_offset bottom
= sect_off
;
78 sect_offset top
= sect_off
+ get_length ();
79 return off
>= bottom
&& off
< top
;
83 /* Expected enum dwarf_unit_type for read_comp_unit_head. */
84 enum class rcuh_kind
{ COMPILE
, TYPE
};
86 /* Read in the comp unit header information from the debug_info at info_ptr.
87 Use rcuh_kind::COMPILE as the default type if not known by the caller.
88 NOTE: This leaves members offset, first_die_offset to be filled in
90 extern const gdb_byte
*read_comp_unit_head
91 (struct comp_unit_head
*cu_header
,
92 const gdb_byte
*info_ptr
,
93 struct dwarf2_section_info
*section
,
94 rcuh_kind section_kind
);
96 /* Read in a CU/TU header and perform some basic error checking.
97 The contents of the header are stored in HEADER.
98 The result is a pointer to the start of the first DIE. */
99 extern const gdb_byte
*read_and_check_comp_unit_head
100 (struct dwarf2_per_objfile
*dwarf2_per_objfile
,
101 struct comp_unit_head
*header
,
102 struct dwarf2_section_info
*section
,
103 struct dwarf2_section_info
*abbrev_section
,
104 const gdb_byte
*info_ptr
,
105 rcuh_kind section_kind
);
107 /* Read an offset from the data stream. The size of the offset is
108 given by cu_header->offset_size. */
110 extern LONGEST
read_offset (bfd
*abfd
, const gdb_byte
*buf
,
111 const struct comp_unit_head
*cu_header
,
112 unsigned int *bytes_read
);
114 #endif /* GDB_DWARF2_COMP_UNIT_H */