xref: /netbsd-src/external/gpl3/gdb.old/dist/gdb/dwarf2/abbrev.h (revision f8cf1a9151c7af1cb0bd8b09c13c66bca599c027)
1 /* DWARF abbrev table
2 
3    Copyright (C) 1994-2023 Free Software Foundation, Inc.
4 
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
10    support.
11 
12    This file is part of GDB.
13 
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.
18 
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.
23 
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/>.  */
26 
27 #ifndef GDB_DWARF2_ABBREV_H
28 #define GDB_DWARF2_ABBREV_H
29 
30 #include "hashtab.h"
31 
32 struct attr_abbrev
33 {
34   ENUM_BITFIELD(dwarf_attribute) name : 16;
35   ENUM_BITFIELD(dwarf_form) form : 16;
36 
37   /* It is valid only if FORM is DW_FORM_implicit_const.  */
38   LONGEST implicit_const;
39 };
40 
41 /* This data structure holds the information of an abbrev.  */
42 struct abbrev_info
43 {
44   /* Number identifying abbrev.  */
45   unsigned int number;
46   /* DWARF tag.  */
47   ENUM_BITFIELD (dwarf_tag) tag : 16;
48   /* True if the DIE has children.  */
49   bool has_children;
50   bool interesting;
51   unsigned short size_if_constant;
52   unsigned short sibling_offset;
53   /* Number of attributes.  */
54   unsigned short num_attrs;
55   /* An array of attribute descriptions, allocated using the struct
56      hack.  */
57   struct attr_abbrev attrs[1];
58 };
59 
60 struct abbrev_table;
61 typedef std::unique_ptr<struct abbrev_table> abbrev_table_up;
62 
63 /* Top level data structure to contain an abbreviation table.  */
64 
65 struct abbrev_table
66 {
67   /* Read an abbrev table from the indicated section, at the given
68      offset.  The caller is responsible for ensuring that the section
69      has already been read.  */
70 
71   static abbrev_table_up read (struct dwarf2_section_info *section,
72 			       sect_offset sect_off);
73 
74   /* Look up an abbrev in the table.
75      Returns NULL if the abbrev is not found.  */
76 
77   const struct abbrev_info *lookup_abbrev (unsigned int abbrev_number) const
78   {
79     struct abbrev_info search;
80     search.number = abbrev_number;
81 
82     return (struct abbrev_info *) htab_find_with_hash (m_abbrevs.get (),
83 						       &search,
84 						       abbrev_number);
85   }
86 
87   /* Where the abbrev table came from.
88      This is used as a sanity check when the table is used.  */
89   const sect_offset sect_off;
90 
91   struct dwarf2_section_info *section;
92 
93 private:
94 
95   abbrev_table (sect_offset off, struct dwarf2_section_info *sect);
96 
97   DISABLE_COPY_AND_ASSIGN (abbrev_table);
98 
99   /* Add an abbreviation to the table.  */
100   void add_abbrev (struct abbrev_info *abbrev);
101 
102   /* Hash table of abbrevs.  */
103   htab_up m_abbrevs;
104 
105   /* Storage for the abbrev table.  */
106   auto_obstack m_abbrev_obstack;
107 };
108 
109 #endif /* GDB_DWARF2_ABBREV_H */
110