1 /* DWARF 2 abbreviations
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/>. */
28 #include "dwarf2/read.h"
29 #include "dwarf2/abbrev.h"
30 #include "dwarf2/leb.h"
33 /* Hash function for an abbrev. */
36 hash_abbrev (const void *item
)
38 const struct abbrev_info
*info
= (const struct abbrev_info
*) item
;
42 /* Comparison function for abbrevs. */
45 eq_abbrev (const void *lhs
, const void *rhs
)
47 const struct abbrev_info
*l_info
= (const struct abbrev_info
*) lhs
;
48 const struct abbrev_info
*r_info
= (const struct abbrev_info
*) rhs
;
49 return l_info
->number
== r_info
->number
;
52 /* Abbreviation tables.
54 In DWARF version 2, the description of the debugging information is
55 stored in a separate .debug_abbrev section. Before we read any
56 dies from a section we read in all abbreviations and install them
59 abbrev_table::abbrev_table (sect_offset off
)
61 m_abbrevs (htab_create_alloc (20, hash_abbrev
, eq_abbrev
,
62 nullptr, xcalloc
, xfree
))
66 /* Allocate space for a struct abbrev_info object in ABBREV_TABLE. */
69 abbrev_table::alloc_abbrev ()
71 struct abbrev_info
*abbrev
;
73 abbrev
= XOBNEW (&m_abbrev_obstack
, struct abbrev_info
);
74 memset (abbrev
, 0, sizeof (struct abbrev_info
));
79 /* Add an abbreviation to the table. */
82 abbrev_table::add_abbrev (unsigned int abbrev_number
,
83 struct abbrev_info
*abbrev
)
85 void **slot
= htab_find_slot (m_abbrevs
.get (), abbrev
, INSERT
);
89 /* Look up an abbrev in the table.
90 Returns NULL if the abbrev is not found. */
93 abbrev_table::lookup_abbrev (unsigned int abbrev_number
)
95 struct abbrev_info search
;
96 search
.number
= abbrev_number
;
98 return (struct abbrev_info
*) htab_find (m_abbrevs
.get (), &search
);
101 /* Read in an abbrev table. */
104 abbrev_table::read (struct objfile
*objfile
,
105 struct dwarf2_section_info
*section
,
106 sect_offset sect_off
)
108 bfd
*abfd
= section
->get_bfd_owner ();
109 const gdb_byte
*abbrev_ptr
;
110 struct abbrev_info
*cur_abbrev
;
111 unsigned int abbrev_number
, bytes_read
, abbrev_name
;
112 unsigned int abbrev_form
;
113 std::vector
<struct attr_abbrev
> cur_attrs
;
115 abbrev_table_up
abbrev_table (new struct abbrev_table (sect_off
));
117 section
->read (objfile
);
118 abbrev_ptr
= section
->buffer
+ to_underlying (sect_off
);
119 abbrev_number
= read_unsigned_leb128 (abfd
, abbrev_ptr
, &bytes_read
);
120 abbrev_ptr
+= bytes_read
;
122 /* Loop until we reach an abbrev number of 0. */
123 while (abbrev_number
)
126 cur_abbrev
= abbrev_table
->alloc_abbrev ();
128 /* read in abbrev header */
129 cur_abbrev
->number
= abbrev_number
;
131 = (enum dwarf_tag
) read_unsigned_leb128 (abfd
, abbrev_ptr
, &bytes_read
);
132 abbrev_ptr
+= bytes_read
;
133 cur_abbrev
->has_children
= read_1_byte (abfd
, abbrev_ptr
);
136 /* now read in declarations */
139 LONGEST implicit_const
;
141 abbrev_name
= read_unsigned_leb128 (abfd
, abbrev_ptr
, &bytes_read
);
142 abbrev_ptr
+= bytes_read
;
143 abbrev_form
= read_unsigned_leb128 (abfd
, abbrev_ptr
, &bytes_read
);
144 abbrev_ptr
+= bytes_read
;
145 if (abbrev_form
== DW_FORM_implicit_const
)
147 implicit_const
= read_signed_leb128 (abfd
, abbrev_ptr
,
149 abbrev_ptr
+= bytes_read
;
153 /* Initialize it due to a false compiler warning. */
157 if (abbrev_name
== 0)
160 cur_attrs
.emplace_back ();
161 struct attr_abbrev
&cur_attr
= cur_attrs
.back ();
162 cur_attr
.name
= (enum dwarf_attribute
) abbrev_name
;
163 cur_attr
.form
= (enum dwarf_form
) abbrev_form
;
164 cur_attr
.implicit_const
= implicit_const
;
167 cur_abbrev
->num_attrs
= cur_attrs
.size ();
169 XOBNEWVEC (&abbrev_table
->m_abbrev_obstack
, struct attr_abbrev
,
170 cur_abbrev
->num_attrs
);
171 memcpy (cur_abbrev
->attrs
, cur_attrs
.data (),
172 cur_abbrev
->num_attrs
* sizeof (struct attr_abbrev
));
174 abbrev_table
->add_abbrev (abbrev_number
, cur_abbrev
);
176 /* Get next abbreviation.
177 Under Irix6 the abbreviations for a compilation unit are not
178 always properly terminated with an abbrev number of 0.
179 Exit loop if we encounter an abbreviation which we have
180 already read (which means we are about to read the abbreviations
181 for the next compile unit) or if the end of the abbreviation
183 if ((unsigned int) (abbrev_ptr
- section
->buffer
) >= section
->size
)
185 abbrev_number
= read_unsigned_leb128 (abfd
, abbrev_ptr
, &bytes_read
);
186 abbrev_ptr
+= bytes_read
;
187 if (abbrev_table
->lookup_abbrev (abbrev_number
) != NULL
)
This page took 0.03512 seconds and 4 git commands to generate.