1 /* Return scope DIEs containing PC address. 2 Copyright (C) 2005, 2007 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 5 Red Hat elfutils is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by the 7 Free Software Foundation; version 2 of the License. 8 9 Red Hat elfutils is distributed in the hope that it will be useful, but 10 WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 General Public License for more details. 13 14 You should have received a copy of the GNU General Public License along 15 with Red Hat elfutils; if not, write to the Free Software Foundation, 16 Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 17 18 In addition, as a special exception, Red Hat, Inc. gives You the 19 additional right to link the code of Red Hat elfutils with code licensed 20 under any Open Source Initiative certified open source license 21 (http://www.opensource.org/licenses/index.php) which requires the 22 distribution of source code with any binary distribution and to 23 distribute linked combinations of the two. Non-GPL Code permitted under 24 this exception must only link to the code of Red Hat elfutils through 25 those well defined interfaces identified in the file named EXCEPTION 26 found in the source code files (the "Approved Interfaces"). The files 27 of Non-GPL Code may instantiate templates or use macros or inline 28 functions from the Approved Interfaces without causing the resulting 29 work to be covered by the GNU General Public License. Only Red Hat, 30 Inc. may make changes or additions to the list of Approved Interfaces. 31 Red Hat's grant of this exception is conditioned upon your not adding 32 any new exceptions. If you wish to add a new Approved Interface or 33 exception, please contact Red Hat. You must obey the GNU General Public 34 License in all respects for all of the Red Hat elfutils code and other 35 code used in conjunction with Red Hat elfutils except the Non-GPL Code 36 covered by this exception. If you modify this file, you may extend this 37 exception to your version of the file, but you are not obligated to do 38 so. If you do not wish to provide this exception without modification, 39 you must delete this exception statement from your version and license 40 this file solely under the GPL without exception. 41 42 Red Hat elfutils is an included package of the Open Invention Network. 43 An included package of the Open Invention Network is a package for which 44 Open Invention Network licensees cross-license their patents. No patent 45 license is granted, either expressly or impliedly, by designation as an 46 included package. Should you wish to participate in the Open Invention 47 Network licensing program, please visit www.openinventionnetwork.com 48 <http://www.openinventionnetwork.com>. */ 49 50 #ifdef HAVE_CONFIG_H 51 # include <config.h> 52 #endif 53 54 #include <assert.h> 55 #include <stdlib.h> 56 #include "libdwP.h" 57 #include <dwarf.h> 58 59 60 struct args 61 { 62 Dwarf_Addr pc; 63 Dwarf_Die *scopes; 64 unsigned int inlined, nscopes; 65 Dwarf_Die inlined_origin; 66 }; 67 68 /* Preorder visitor: prune the traversal if this DIE does not contain PC. */ 69 static int 70 pc_match (unsigned int depth, struct Dwarf_Die_Chain *die, void *arg) 71 { 72 struct args *a = arg; 73 74 if (a->scopes != NULL) 75 die->prune = true; 76 else 77 { 78 /* dwarf_haspc returns an error if there are no appropriate attributes. 79 But we use it indiscriminantly instead of presuming which tags can 80 have PC attributes. So when it fails for that reason, treat it just 81 as a nonmatching return. */ 82 int result = INTUSE(dwarf_haspc) (&die->die, a->pc); 83 if (result < 0) 84 { 85 int error = INTUSE(dwarf_errno) (); 86 if (error != DWARF_E_NOERROR && error != DWARF_E_NO_DEBUG_RANGES) 87 { 88 __libdw_seterrno (error); 89 return -1; 90 } 91 result = 0; 92 } 93 if (result == 0) 94 die->prune = true; 95 96 if (!die->prune 97 && INTUSE (dwarf_tag) (&die->die) == DW_TAG_inlined_subroutine) 98 a->inlined = depth; 99 } 100 101 return 0; 102 } 103 104 /* Preorder visitor for second partial traversal after finding a 105 concrete inlined instance. */ 106 static int 107 origin_match (unsigned int depth, struct Dwarf_Die_Chain *die, void *arg) 108 { 109 struct args *a = arg; 110 111 if (die->die.addr != a->inlined_origin.addr) 112 return 0; 113 114 /* We have a winner! This is the abstract definition of the inline 115 function of which A->scopes[A->nscopes - 1] is a concrete instance. 116 */ 117 118 unsigned int nscopes = a->nscopes + depth; 119 Dwarf_Die *scopes = realloc (a->scopes, nscopes * sizeof scopes[0]); 120 if (scopes == NULL) 121 { 122 free (a->scopes); 123 __libdw_seterrno (DWARF_E_NOMEM); 124 return -1; 125 } 126 127 a->scopes = scopes; 128 do 129 { 130 die = die->parent; 131 scopes[a->nscopes++] = die->die; 132 } 133 while (a->nscopes < nscopes); 134 assert (die->parent == NULL); 135 return a->nscopes; 136 } 137 138 /* Postorder visitor: first (innermost) call wins. */ 139 static int 140 pc_record (unsigned int depth, struct Dwarf_Die_Chain *die, void *arg) 141 { 142 struct args *a = arg; 143 144 if (die->prune) 145 return 0; 146 147 if (a->scopes == NULL) 148 { 149 /* We have hit the innermost DIE that contains the target PC. */ 150 151 a->nscopes = depth + 1 - a->inlined; 152 a->scopes = malloc (a->nscopes * sizeof a->scopes[0]); 153 if (a->scopes == NULL) 154 { 155 __libdw_seterrno (DWARF_E_NOMEM); 156 return -1; 157 } 158 159 for (unsigned int i = 0; i < a->nscopes; ++i) 160 { 161 a->scopes[i] = die->die; 162 die = die->parent; 163 } 164 165 if (a->inlined == 0) 166 { 167 assert (die == NULL); 168 return a->nscopes; 169 } 170 171 /* This is the concrete inlined instance itself. 172 Record its abstract_origin pointer. */ 173 Dwarf_Die *const inlinedie = &a->scopes[depth - a->inlined]; 174 175 assert (INTUSE (dwarf_tag) (inlinedie) == DW_TAG_inlined_subroutine); 176 Dwarf_Attribute attr_mem; 177 Dwarf_Attribute *attr = INTUSE (dwarf_attr) (inlinedie, 178 DW_AT_abstract_origin, 179 &attr_mem); 180 if (INTUSE (dwarf_formref_die) (attr, &a->inlined_origin) == NULL) 181 return -1; 182 return 0; 183 } 184 185 186 /* We've recorded the scopes back to one that is a concrete inlined 187 instance. Now return out of the traversal back to the scope 188 containing that instance. */ 189 190 assert (a->inlined); 191 if (depth >= a->inlined) 192 /* Not there yet. */ 193 return 0; 194 195 /* Now we are in a scope that contains the concrete inlined instance. 196 Search it for the inline function's abstract definition. 197 If we don't find it, return to search the containing scope. 198 If we do find it, the nonzero return value will bail us out 199 of the postorder traversal. */ 200 return __libdw_visit_scopes (depth, die, &origin_match, NULL, a); 201 } 202 203 204 int 205 dwarf_getscopes (Dwarf_Die *cudie, Dwarf_Addr pc, Dwarf_Die **scopes) 206 { 207 if (cudie == NULL) 208 return -1; 209 210 struct Dwarf_Die_Chain cu = { .parent = NULL, .die = *cudie }; 211 struct args a = { .pc = pc }; 212 213 int result = __libdw_visit_scopes (0, &cu, &pc_match, &pc_record, &a); 214 215 if (result == 0 && a.scopes != NULL) 216 result = __libdw_visit_scopes (0, &cu, &origin_match, NULL, &a); 217 218 if (result > 0) 219 *scopes = a.scopes; 220 221 return result; 222 } 223
