Branch data Line data Source code
1 : : /* Return scope DIEs containing PC address.
2 : : Copyright (C) 2005, 2007 Red Hat, Inc.
3 : : This file is part of elfutils.
4 : :
5 : : This file is free software; you can redistribute it and/or modify
6 : : it under the terms of either
7 : :
8 : : * the GNU Lesser General Public License as published by the Free
9 : : Software Foundation; either version 3 of the License, or (at
10 : : your option) any later version
11 : :
12 : : or
13 : :
14 : : * the GNU General Public License as published by the Free
15 : : Software Foundation; either version 2 of the License, or (at
16 : : your option) any later version
17 : :
18 : : or both in parallel, as here.
19 : :
20 : : elfutils is distributed in the hope that it will be useful, but
21 : : WITHOUT ANY WARRANTY; without even the implied warranty of
22 : : MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 : : General Public License for more details.
24 : :
25 : : You should have received copies of the GNU General Public License and
26 : : the GNU Lesser General Public License along with this program. If
27 : : not, see <http://www.gnu.org/licenses/>. */
28 : :
29 : : #ifdef HAVE_CONFIG_H
30 : : # include <config.h>
31 : : #endif
32 : :
33 : : #include <assert.h>
34 : : #include <stdlib.h>
35 : : #include "libdwP.h"
36 : : #include <dwarf.h>
37 : :
38 : :
39 : : struct args
40 : : {
41 : : Dwarf_Addr pc;
42 : : Dwarf_Die *scopes;
43 : : unsigned int inlined, nscopes;
44 : : Dwarf_Die inlined_origin;
45 : : };
46 : :
47 : : /* Preorder visitor: prune the traversal if this DIE does not contain PC. */
48 : : static int
49 : 12 : pc_match (unsigned int depth, struct Dwarf_Die_Chain *die, void *arg)
50 : : {
51 : 12 : struct args *a = arg;
52 : :
53 [ + + ]: 12 : if (a->scopes != NULL)
54 : 1 : die->prune = true;
55 : : else
56 : : {
57 : : /* dwarf_haspc returns an error if there are no appropriate attributes.
58 : : But we use it indiscriminantly instead of presuming which tags can
59 : : have PC attributes. So when it fails for that reason, treat it just
60 : : as a nonmatching return. */
61 : 11 : int result = INTUSE(dwarf_haspc) (&die->die, a->pc);
62 [ - + ]: 11 : if (result < 0)
63 : : {
64 : 0 : int error = INTUSE(dwarf_errno) ();
65 [ # # ]: 0 : if (error != DWARF_E_NOERROR && error != DWARF_E_NO_DEBUG_RANGES)
66 : : {
67 : 0 : __libdw_seterrno (error);
68 : 0 : return -1;
69 : : }
70 : : result = 0;
71 : : }
72 [ + + ]: 11 : if (result == 0)
73 : 8 : die->prune = true;
74 : :
75 [ + + ]: 11 : if (!die->prune
76 [ + + ]: 3 : && INTUSE (dwarf_tag) (&die->die) == DW_TAG_inlined_subroutine)
77 : 12 : a->inlined = depth;
78 : : }
79 : :
80 : : return 0;
81 : : }
82 : :
83 : : /* Preorder visitor for second partial traversal after finding a
84 : : concrete inlined instance. */
85 : : static int
86 : 5 : origin_match (unsigned int depth, struct Dwarf_Die_Chain *die, void *arg)
87 : : {
88 : 5 : struct args *a = arg;
89 : :
90 [ + + ]: 5 : if (die->die.addr != a->inlined_origin.addr)
91 : : return 0;
92 : :
93 : : /* We have a winner! This is the abstract definition of the inline
94 : : function of which A->scopes[A->nscopes - 1] is a concrete instance.
95 : : */
96 : :
97 : 1 : unsigned int nscopes = a->nscopes + depth;
98 : 1 : Dwarf_Die *scopes = realloc (a->scopes, nscopes * sizeof scopes[0]);
99 [ - + ]: 1 : if (scopes == NULL)
100 : : {
101 : 0 : free (a->scopes);
102 : 0 : __libdw_seterrno (DWARF_E_NOMEM);
103 : 0 : return -1;
104 : : }
105 : :
106 : 1 : a->scopes = scopes;
107 : : do
108 : : {
109 : 1 : die = die->parent;
110 : 1 : scopes[a->nscopes++] = die->die;
111 : : }
112 [ - + ]: 1 : while (a->nscopes < nscopes);
113 [ - + ]: 1 : assert (die->parent == NULL);
114 : 5 : return a->nscopes;
115 : : }
116 : :
117 : : /* Postorder visitor: first (innermost) call wins. */
118 : : static int
119 : 12 : pc_record (unsigned int depth, struct Dwarf_Die_Chain *die, void *arg)
120 : : {
121 : 12 : struct args *a = arg;
122 : :
123 [ + + ]: 12 : if (die->prune)
124 : : return 0;
125 : :
126 [ + + ]: 3 : if (a->scopes == NULL)
127 : : {
128 : : /* We have hit the innermost DIE that contains the target PC. */
129 : :
130 : 2 : a->nscopes = depth + 1 - a->inlined;
131 : 2 : a->scopes = malloc (a->nscopes * sizeof a->scopes[0]);
132 [ + - ]: 2 : if (a->scopes == NULL)
133 : : {
134 : 0 : __libdw_seterrno (DWARF_E_NOMEM);
135 : : return -1;
136 : : }
137 : :
138 [ + + ]: 5 : for (unsigned int i = 0; i < a->nscopes; ++i)
139 : : {
140 : 3 : a->scopes[i] = die->die;
141 : 3 : die = die->parent;
142 : : }
143 : :
144 [ + + ]: 2 : if (a->inlined == 0)
145 : : {
146 [ - + ]: 1 : assert (die == NULL);
147 : 1 : return a->nscopes;
148 : : }
149 : :
150 : : /* This is the concrete inlined instance itself.
151 : : Record its abstract_origin pointer. */
152 : 1 : Dwarf_Die *const inlinedie = &a->scopes[depth - a->inlined];
153 : :
154 [ - + ]: 1 : assert (INTUSE (dwarf_tag) (inlinedie) == DW_TAG_inlined_subroutine);
155 : : Dwarf_Attribute attr_mem;
156 : 1 : Dwarf_Attribute *attr = INTUSE (dwarf_attr) (inlinedie,
157 : : DW_AT_abstract_origin,
158 : : &attr_mem);
159 [ + - ]: 2 : if (INTUSE (dwarf_formref_die) (attr, &a->inlined_origin) == NULL)
160 : : return -1;
161 : : return 0;
162 : : }
163 : :
164 : :
165 : : /* We've recorded the scopes back to one that is a concrete inlined
166 : : instance. Now return out of the traversal back to the scope
167 : : containing that instance. */
168 : :
169 [ - + ]: 1 : assert (a->inlined);
170 [ + - ]: 1 : if (depth >= a->inlined)
171 : : /* Not there yet. */
172 : : return 0;
173 : :
174 : : /* Now we are in a scope that contains the concrete inlined instance.
175 : : Search it for the inline function's abstract definition.
176 : : If we don't find it, return to search the containing scope.
177 : : If we do find it, the nonzero return value will bail us out
178 : : of the postorder traversal. */
179 : 12 : return __libdw_visit_scopes (depth, die, &origin_match, NULL, a);
180 : : }
181 : :
182 : :
183 : : int
184 : 8 : dwarf_getscopes (Dwarf_Die *cudie, Dwarf_Addr pc, Dwarf_Die **scopes)
185 : : {
186 [ + + ]: 8 : if (cudie == NULL)
187 : : return -1;
188 : :
189 : 2 : struct Dwarf_Die_Chain cu = { .parent = NULL, .die = *cudie };
190 : 2 : struct args a = { .pc = pc };
191 : :
192 : 2 : int result = __libdw_visit_scopes (0, &cu, &pc_match, &pc_record, &a);
193 : :
194 [ + + ][ + - ]: 2 : if (result == 0 && a.scopes != NULL)
195 : 1 : result = __libdw_visit_scopes (0, &cu, &origin_match, NULL, &a);
196 : :
197 [ + - ]: 2 : if (result > 0)
198 : 8 : *scopes = a.scopes;
199 : :
200 : : return result;
201 : : }
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