1 /* Find entry breakpoint locations for a function. 2 Copyright (C) 2005, 2008 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 #include "libdwP.h" 54 #include <dwarf.h> 55 #include <stdlib.h> 56 57 58 int 59 dwarf_entry_breakpoints (die, bkpts) 60 Dwarf_Die *die; 61 Dwarf_Addr **bkpts; 62 { 63 int nbkpts = 0; 64 *bkpts = NULL; 65 66 /* Add one breakpoint location to the result vector. */ 67 inline int add_bkpt (Dwarf_Addr pc) 68 { 69 Dwarf_Addr *newlist = realloc (*bkpts, ++nbkpts * sizeof newlist[0]); 70 if (newlist == NULL) 71 { 72 free (*bkpts); 73 *bkpts = NULL; 74 __libdw_seterrno (DWARF_E_NOMEM); 75 return -1; 76 } 77 newlist[nbkpts - 1] = pc; 78 *bkpts = newlist; 79 return nbkpts; 80 } 81 82 /* Fallback result, break at the entrypc/lowpc value. */ 83 inline int entrypc_bkpt (void) 84 { 85 Dwarf_Addr pc; 86 return INTUSE(dwarf_entrypc) (die, &pc) < 0 ? -1 : add_bkpt (pc); 87 } 88 89 /* Fetch the CU's line records to look for this DIE's addresses. */ 90 Dwarf_Die cudie = CUDIE (die->cu); 91 Dwarf_Lines *lines; 92 size_t nlines; 93 if (INTUSE(dwarf_getsrclines) (&cudie, &lines, &nlines) < 0) 94 { 95 int error = INTUSE (dwarf_errno) (); 96 if (error == DWARF_E_NO_DEBUG_LINE) 97 return entrypc_bkpt (); 98 __libdw_seterrno (error); 99 return -1; 100 } 101 102 /* Search a contiguous PC range for prologue-end markers. 103 If DWARF, look for proper markers. 104 Failing that, if ADHOC, look for the ad hoc convention. */ 105 inline int search_range (Dwarf_Addr low, Dwarf_Addr high, 106 bool dwarf, bool adhoc) 107 { 108 size_t l = 0, u = nlines; 109 while (l < u) 110 { 111 size_t idx = (l + u) / 2; 112 if (lines->info[idx].addr < low) 113 l = idx + 1; 114 else if (lines->info[idx].addr > low) 115 u = idx; 116 else if (lines->info[idx].end_sequence) 117 l = idx + 1; 118 else 119 { 120 l = idx; 121 break; 122 } 123 } 124 if (l < u) 125 { 126 if (dwarf) 127 for (size_t i = l; i < u && lines->info[i].addr < high; ++i) 128 if (lines->info[i].prologue_end 129 && add_bkpt (lines->info[i].addr) < 0) 130 return -1; 131 if (adhoc && nbkpts == 0) 132 while (++l < nlines && lines->info[l].addr < high) 133 if (!lines->info[l].end_sequence) 134 return add_bkpt (lines->info[l].addr); 135 return nbkpts; 136 } 137 __libdw_seterrno (DWARF_E_INVALID_DWARF); 138 return -1; 139 } 140 141 /* Search each contiguous address range for DWARF prologue_end markers. */ 142 143 Dwarf_Addr base; 144 Dwarf_Addr begin; 145 Dwarf_Addr end; 146 ptrdiff_t offset = INTUSE(dwarf_ranges) (die, 0, &base, &begin, &end); 147 if (offset < 0) 148 return -1; 149 150 /* Most often there is a single contiguous PC range for the DIE. */ 151 if (offset == 1) 152 return search_range (begin, end, true, true) ?: entrypc_bkpt (); 153 154 Dwarf_Addr lowpc = (Dwarf_Addr) -1l; 155 Dwarf_Addr highpc = (Dwarf_Addr) -1l; 156 while (offset > 0) 157 { 158 /* We have an address range entry. */ 159 if (search_range (begin, end, true, false) < 0) 160 return -1; 161 162 if (begin < lowpc) 163 { 164 lowpc = begin; 165 highpc = end; 166 } 167 168 offset = INTUSE(dwarf_ranges) (die, offset, &base, &begin, &end); 169 } 170 171 /* If we didn't find any proper DWARF markers, then look in the 172 lowest-addressed range for an ad hoc marker. Failing that, 173 fall back to just using the entrypc value. */ 174 return (nbkpts 175 ?: (lowpc == (Dwarf_Addr) -1l ? 0 176 : search_range (lowpc, highpc, false, true)) 177 ?: entrypc_bkpt ()); 178 } 179
