1 /* Enumerate the PC ranges covered by a DIE. 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 "libdwP.h" 55 #include <dwarf.h> 56 #include <assert.h> 57 58 59 ptrdiff_t 60 dwarf_ranges (Dwarf_Die *die, ptrdiff_t offset, Dwarf_Addr *basep, 61 Dwarf_Addr *startp, Dwarf_Addr *endp) 62 { 63 if (die == NULL) 64 return -1; 65 66 if (offset == 0 67 /* Usually there is a single contiguous range. */ 68 && INTUSE(dwarf_highpc) (die, endp) == 0 69 && INTUSE(dwarf_lowpc) (die, startp) == 0) 70 /* A offset into .debug_ranges will never be 1, it must be at least a 71 multiple of 4. So we can return 1 as a special case value to mark 72 there are no ranges to look for on the next call. */ 73 return 1; 74 75 if (offset == 1) 76 return 0; 77 78 /* We have to look for a noncontiguous range. */ 79 80 const Elf_Data *d = die->cu->dbg->sectiondata[IDX_debug_ranges]; 81 if (d == NULL) 82 { 83 __libdw_seterrno (DWARF_E_NO_DEBUG_RANGES); 84 return -1; 85 } 86 87 if (offset == 0) 88 { 89 Dwarf_Attribute attr_mem; 90 Dwarf_Attribute *attr = INTUSE(dwarf_attr) (die, DW_AT_ranges, 91 &attr_mem); 92 if (attr == NULL) 93 return -1; 94 95 /* Must have the form data4 or data8 which act as an offset. */ 96 Dwarf_Word start_offset; 97 if (INTUSE(dwarf_formudata) (attr, &start_offset) != 0) 98 return -1; 99 100 offset = start_offset; 101 assert ((Dwarf_Word) offset == start_offset); 102 103 /* Fetch the CU's base address. */ 104 Dwarf_Die cudie = CUDIE (attr->cu); 105 106 /* Find the base address of the compilation unit. It will 107 normally be specified by DW_AT_low_pc. In DWARF-3 draft 4, 108 the base address could be overridden by DW_AT_entry_pc. It's 109 been removed, but GCC emits DW_AT_entry_pc and not DW_AT_lowpc 110 for compilation units with discontinuous ranges. */ 111 if (unlikely (INTUSE(dwarf_lowpc) (&cudie, basep) != 0) 112 && INTUSE(dwarf_formaddr) (INTUSE(dwarf_attr) (&cudie, 113 DW_AT_entry_pc, 114 &attr_mem), 115 basep) != 0) 116 { 117 if (INTUSE(dwarf_errno) () == 0) 118 { 119 invalid: 120 __libdw_seterrno (DWARF_E_INVALID_DWARF); 121 } 122 return -1; 123 } 124 } 125 else if (offset < 0 || (size_t) offset >= d->d_size) 126 { 127 __libdw_seterrno (DWARF_E_INVALID_OFFSET); 128 return -1l; 129 } 130 131 unsigned char *readp = d->d_buf + offset; 132 133 next: 134 if ((unsigned char *) d->d_buf + d->d_size - readp 135 < die->cu->address_size * 2) 136 goto invalid; 137 138 Dwarf_Addr begin; 139 Dwarf_Addr end; 140 if (die->cu->address_size == 8) 141 { 142 begin = read_8ubyte_unaligned_inc (die->cu->dbg, readp); 143 end = read_8ubyte_unaligned_inc (die->cu->dbg, readp); 144 if (begin == (uint64_t) -1l) /* Base address entry. */ 145 { 146 *basep = end; 147 goto next; 148 } 149 } 150 else 151 { 152 begin = read_4ubyte_unaligned_inc (die->cu->dbg, readp); 153 end = read_4ubyte_unaligned_inc (die->cu->dbg, readp); 154 if (begin == (uint32_t) -1) /* Base address entry. */ 155 { 156 *basep = end; 157 goto next; 158 } 159 } 160 161 if (begin == 0 && end == 0) /* End of list entry. */ 162 return 0; 163 164 /* We have an address range entry. */ 165 *startp = *basep + begin; 166 *endp = *basep + end; 167 return readp - (unsigned char *) d->d_buf; 168 } 169 INTDEF (dwarf_ranges) 170
