125b3c049e70834cf33790a28643ab058b507b35cBen Cheng/* Find entry breakpoint locations for a function.
225b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Copyright (C) 2005-2009 Red Hat, Inc.
325b3c049e70834cf33790a28643ab058b507b35cBen Cheng   This file is part of Red Hat elfutils.
425b3c049e70834cf33790a28643ab058b507b35cBen Cheng
525b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Red Hat elfutils is free software; you can redistribute it and/or modify
625b3c049e70834cf33790a28643ab058b507b35cBen Cheng   it under the terms of the GNU General Public License as published by the
725b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Free Software Foundation; version 2 of the License.
825b3c049e70834cf33790a28643ab058b507b35cBen Cheng
925b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Red Hat elfutils is distributed in the hope that it will be useful, but
1025b3c049e70834cf33790a28643ab058b507b35cBen Cheng   WITHOUT ANY WARRANTY; without even the implied warranty of
1125b3c049e70834cf33790a28643ab058b507b35cBen Cheng   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
1225b3c049e70834cf33790a28643ab058b507b35cBen Cheng   General Public License for more details.
1325b3c049e70834cf33790a28643ab058b507b35cBen Cheng
1425b3c049e70834cf33790a28643ab058b507b35cBen Cheng   You should have received a copy of the GNU General Public License along
1525b3c049e70834cf33790a28643ab058b507b35cBen Cheng   with Red Hat elfutils; if not, write to the Free Software Foundation,
1625b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
1725b3c049e70834cf33790a28643ab058b507b35cBen Cheng
1825b3c049e70834cf33790a28643ab058b507b35cBen Cheng   In addition, as a special exception, Red Hat, Inc. gives You the
1925b3c049e70834cf33790a28643ab058b507b35cBen Cheng   additional right to link the code of Red Hat elfutils with code licensed
2025b3c049e70834cf33790a28643ab058b507b35cBen Cheng   under any Open Source Initiative certified open source license
2125b3c049e70834cf33790a28643ab058b507b35cBen Cheng   (http://www.opensource.org/licenses/index.php) which requires the
2225b3c049e70834cf33790a28643ab058b507b35cBen Cheng   distribution of source code with any binary distribution and to
2325b3c049e70834cf33790a28643ab058b507b35cBen Cheng   distribute linked combinations of the two.  Non-GPL Code permitted under
2425b3c049e70834cf33790a28643ab058b507b35cBen Cheng   this exception must only link to the code of Red Hat elfutils through
2525b3c049e70834cf33790a28643ab058b507b35cBen Cheng   those well defined interfaces identified in the file named EXCEPTION
2625b3c049e70834cf33790a28643ab058b507b35cBen Cheng   found in the source code files (the "Approved Interfaces").  The files
2725b3c049e70834cf33790a28643ab058b507b35cBen Cheng   of Non-GPL Code may instantiate templates or use macros or inline
2825b3c049e70834cf33790a28643ab058b507b35cBen Cheng   functions from the Approved Interfaces without causing the resulting
2925b3c049e70834cf33790a28643ab058b507b35cBen Cheng   work to be covered by the GNU General Public License.  Only Red Hat,
3025b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Inc. may make changes or additions to the list of Approved Interfaces.
3125b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Red Hat's grant of this exception is conditioned upon your not adding
3225b3c049e70834cf33790a28643ab058b507b35cBen Cheng   any new exceptions.  If you wish to add a new Approved Interface or
3325b3c049e70834cf33790a28643ab058b507b35cBen Cheng   exception, please contact Red Hat.  You must obey the GNU General Public
3425b3c049e70834cf33790a28643ab058b507b35cBen Cheng   License in all respects for all of the Red Hat elfutils code and other
3525b3c049e70834cf33790a28643ab058b507b35cBen Cheng   code used in conjunction with Red Hat elfutils except the Non-GPL Code
3625b3c049e70834cf33790a28643ab058b507b35cBen Cheng   covered by this exception.  If you modify this file, you may extend this
3725b3c049e70834cf33790a28643ab058b507b35cBen Cheng   exception to your version of the file, but you are not obligated to do
3825b3c049e70834cf33790a28643ab058b507b35cBen Cheng   so.  If you do not wish to provide this exception without modification,
3925b3c049e70834cf33790a28643ab058b507b35cBen Cheng   you must delete this exception statement from your version and license
4025b3c049e70834cf33790a28643ab058b507b35cBen Cheng   this file solely under the GPL without exception.
4125b3c049e70834cf33790a28643ab058b507b35cBen Cheng
4225b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Red Hat elfutils is an included package of the Open Invention Network.
4325b3c049e70834cf33790a28643ab058b507b35cBen Cheng   An included package of the Open Invention Network is a package for which
4425b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Open Invention Network licensees cross-license their patents.  No patent
4525b3c049e70834cf33790a28643ab058b507b35cBen Cheng   license is granted, either expressly or impliedly, by designation as an
4625b3c049e70834cf33790a28643ab058b507b35cBen Cheng   included package.  Should you wish to participate in the Open Invention
4725b3c049e70834cf33790a28643ab058b507b35cBen Cheng   Network licensing program, please visit www.openinventionnetwork.com
4825b3c049e70834cf33790a28643ab058b507b35cBen Cheng   <http://www.openinventionnetwork.com>.  */
4925b3c049e70834cf33790a28643ab058b507b35cBen Cheng
5025b3c049e70834cf33790a28643ab058b507b35cBen Cheng#ifdef HAVE_CONFIG_H
5125b3c049e70834cf33790a28643ab058b507b35cBen Cheng# include <config.h>
5225b3c049e70834cf33790a28643ab058b507b35cBen Cheng#endif
5325b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include "libdwP.h"
5425b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <dwarf.h>
5525b3c049e70834cf33790a28643ab058b507b35cBen Cheng#include <stdlib.h>
5625b3c049e70834cf33790a28643ab058b507b35cBen Cheng
5725b3c049e70834cf33790a28643ab058b507b35cBen Cheng
5825b3c049e70834cf33790a28643ab058b507b35cBen Chengint
5925b3c049e70834cf33790a28643ab058b507b35cBen Chengdwarf_entry_breakpoints (die, bkpts)
6025b3c049e70834cf33790a28643ab058b507b35cBen Cheng     Dwarf_Die *die;
6125b3c049e70834cf33790a28643ab058b507b35cBen Cheng     Dwarf_Addr **bkpts;
6225b3c049e70834cf33790a28643ab058b507b35cBen Cheng{
6325b3c049e70834cf33790a28643ab058b507b35cBen Cheng  int nbkpts = 0;
6425b3c049e70834cf33790a28643ab058b507b35cBen Cheng  *bkpts = NULL;
6525b3c049e70834cf33790a28643ab058b507b35cBen Cheng
6625b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* Add one breakpoint location to the result vector.  */
6725b3c049e70834cf33790a28643ab058b507b35cBen Cheng  inline int add_bkpt (Dwarf_Addr pc)
6825b3c049e70834cf33790a28643ab058b507b35cBen Cheng    {
6925b3c049e70834cf33790a28643ab058b507b35cBen Cheng      Dwarf_Addr *newlist = realloc (*bkpts, ++nbkpts * sizeof newlist[0]);
7025b3c049e70834cf33790a28643ab058b507b35cBen Cheng      if (newlist == NULL)
7125b3c049e70834cf33790a28643ab058b507b35cBen Cheng	{
7225b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  free (*bkpts);
7325b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  *bkpts = NULL;
7425b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  __libdw_seterrno (DWARF_E_NOMEM);
7525b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  return -1;
7625b3c049e70834cf33790a28643ab058b507b35cBen Cheng	}
7725b3c049e70834cf33790a28643ab058b507b35cBen Cheng      newlist[nbkpts - 1] = pc;
7825b3c049e70834cf33790a28643ab058b507b35cBen Cheng      *bkpts = newlist;
7925b3c049e70834cf33790a28643ab058b507b35cBen Cheng      return nbkpts;
8025b3c049e70834cf33790a28643ab058b507b35cBen Cheng    }
8125b3c049e70834cf33790a28643ab058b507b35cBen Cheng
8225b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* Fallback result, break at the entrypc/lowpc value.  */
8325b3c049e70834cf33790a28643ab058b507b35cBen Cheng  inline int entrypc_bkpt (void)
8425b3c049e70834cf33790a28643ab058b507b35cBen Cheng    {
8525b3c049e70834cf33790a28643ab058b507b35cBen Cheng      Dwarf_Addr pc;
8625b3c049e70834cf33790a28643ab058b507b35cBen Cheng      return INTUSE(dwarf_entrypc) (die, &pc) < 0 ? -1 : add_bkpt (pc);
8725b3c049e70834cf33790a28643ab058b507b35cBen Cheng    }
8825b3c049e70834cf33790a28643ab058b507b35cBen Cheng
8925b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* Fetch the CU's line records to look for this DIE's addresses.  */
9025b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Die cudie = CUDIE (die->cu);
9125b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Lines *lines;
9225b3c049e70834cf33790a28643ab058b507b35cBen Cheng  size_t nlines;
9325b3c049e70834cf33790a28643ab058b507b35cBen Cheng  if (INTUSE(dwarf_getsrclines) (&cudie, &lines, &nlines) < 0)
9425b3c049e70834cf33790a28643ab058b507b35cBen Cheng    {
9525b3c049e70834cf33790a28643ab058b507b35cBen Cheng      int error = INTUSE (dwarf_errno) ();
9625b3c049e70834cf33790a28643ab058b507b35cBen Cheng      if (error == 0)		/* CU has no DW_AT_stmt_list.  */
9725b3c049e70834cf33790a28643ab058b507b35cBen Cheng	return entrypc_bkpt ();
9825b3c049e70834cf33790a28643ab058b507b35cBen Cheng      __libdw_seterrno (error);
9925b3c049e70834cf33790a28643ab058b507b35cBen Cheng      return -1;
10025b3c049e70834cf33790a28643ab058b507b35cBen Cheng    }
10125b3c049e70834cf33790a28643ab058b507b35cBen Cheng
10225b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* Search a contiguous PC range for prologue-end markers.
10325b3c049e70834cf33790a28643ab058b507b35cBen Cheng     If DWARF, look for proper markers.
10425b3c049e70834cf33790a28643ab058b507b35cBen Cheng     Failing that, if ADHOC, look for the ad hoc convention.  */
10525b3c049e70834cf33790a28643ab058b507b35cBen Cheng  inline int search_range (Dwarf_Addr low, Dwarf_Addr high,
10625b3c049e70834cf33790a28643ab058b507b35cBen Cheng			   bool dwarf, bool adhoc)
10725b3c049e70834cf33790a28643ab058b507b35cBen Cheng    {
10825b3c049e70834cf33790a28643ab058b507b35cBen Cheng      size_t l = 0, u = nlines;
10925b3c049e70834cf33790a28643ab058b507b35cBen Cheng      while (l < u)
11025b3c049e70834cf33790a28643ab058b507b35cBen Cheng	{
11125b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  size_t idx = (l + u) / 2;
11225b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  if (lines->info[idx].addr < low)
11325b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    l = idx + 1;
11425b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  else if (lines->info[idx].addr > low)
11525b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    u = idx;
11625b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  else if (lines->info[idx].end_sequence)
11725b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    l = idx + 1;
11825b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  else
11925b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    {
12025b3c049e70834cf33790a28643ab058b507b35cBen Cheng	      l = idx;
12125b3c049e70834cf33790a28643ab058b507b35cBen Cheng	      break;
12225b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    }
12325b3c049e70834cf33790a28643ab058b507b35cBen Cheng	}
12425b3c049e70834cf33790a28643ab058b507b35cBen Cheng      if (l < u)
12525b3c049e70834cf33790a28643ab058b507b35cBen Cheng	{
12625b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  if (dwarf)
12725b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    for (size_t i = l; i < u && lines->info[i].addr < high; ++i)
12825b3c049e70834cf33790a28643ab058b507b35cBen Cheng	      if (lines->info[i].prologue_end
12925b3c049e70834cf33790a28643ab058b507b35cBen Cheng		  && add_bkpt (lines->info[i].addr) < 0)
13025b3c049e70834cf33790a28643ab058b507b35cBen Cheng		return -1;
13125b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  if (adhoc && nbkpts == 0)
13225b3c049e70834cf33790a28643ab058b507b35cBen Cheng	    while (++l < nlines && lines->info[l].addr < high)
13325b3c049e70834cf33790a28643ab058b507b35cBen Cheng	      if (!lines->info[l].end_sequence)
13425b3c049e70834cf33790a28643ab058b507b35cBen Cheng		return add_bkpt (lines->info[l].addr);
13525b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  return nbkpts;
13625b3c049e70834cf33790a28643ab058b507b35cBen Cheng	}
13725b3c049e70834cf33790a28643ab058b507b35cBen Cheng      __libdw_seterrno (DWARF_E_INVALID_DWARF);
13825b3c049e70834cf33790a28643ab058b507b35cBen Cheng      return -1;
13925b3c049e70834cf33790a28643ab058b507b35cBen Cheng    }
14025b3c049e70834cf33790a28643ab058b507b35cBen Cheng
14125b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* Search each contiguous address range for DWARF prologue_end markers.  */
14225b3c049e70834cf33790a28643ab058b507b35cBen Cheng
14325b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Addr base;
14425b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Addr begin;
14525b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Addr end;
14625b3c049e70834cf33790a28643ab058b507b35cBen Cheng  ptrdiff_t offset = INTUSE(dwarf_ranges) (die, 0, &base, &begin, &end);
14725b3c049e70834cf33790a28643ab058b507b35cBen Cheng  if (offset < 0)
14825b3c049e70834cf33790a28643ab058b507b35cBen Cheng    return -1;
14925b3c049e70834cf33790a28643ab058b507b35cBen Cheng
15025b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* Most often there is a single contiguous PC range for the DIE.  */
15125b3c049e70834cf33790a28643ab058b507b35cBen Cheng  if (offset == 1)
15225b3c049e70834cf33790a28643ab058b507b35cBen Cheng    return search_range (begin, end, true, true) ?: entrypc_bkpt ();
15325b3c049e70834cf33790a28643ab058b507b35cBen Cheng
15425b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Addr lowpc = (Dwarf_Addr) -1l;
15525b3c049e70834cf33790a28643ab058b507b35cBen Cheng  Dwarf_Addr highpc = (Dwarf_Addr) -1l;
15625b3c049e70834cf33790a28643ab058b507b35cBen Cheng  while (offset > 0)
15725b3c049e70834cf33790a28643ab058b507b35cBen Cheng    {
15825b3c049e70834cf33790a28643ab058b507b35cBen Cheng      /* We have an address range entry.  */
15925b3c049e70834cf33790a28643ab058b507b35cBen Cheng      if (search_range (begin, end, true, false) < 0)
16025b3c049e70834cf33790a28643ab058b507b35cBen Cheng	return -1;
16125b3c049e70834cf33790a28643ab058b507b35cBen Cheng
16225b3c049e70834cf33790a28643ab058b507b35cBen Cheng      if (begin < lowpc)
16325b3c049e70834cf33790a28643ab058b507b35cBen Cheng	{
16425b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  lowpc = begin;
16525b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  highpc = end;
16625b3c049e70834cf33790a28643ab058b507b35cBen Cheng	}
16725b3c049e70834cf33790a28643ab058b507b35cBen Cheng
16825b3c049e70834cf33790a28643ab058b507b35cBen Cheng      offset = INTUSE(dwarf_ranges) (die, offset, &base, &begin, &end);
16925b3c049e70834cf33790a28643ab058b507b35cBen Cheng    }
17025b3c049e70834cf33790a28643ab058b507b35cBen Cheng
17125b3c049e70834cf33790a28643ab058b507b35cBen Cheng  /* If we didn't find any proper DWARF markers, then look in the
17225b3c049e70834cf33790a28643ab058b507b35cBen Cheng     lowest-addressed range for an ad hoc marker.  Failing that,
17325b3c049e70834cf33790a28643ab058b507b35cBen Cheng     fall back to just using the entrypc value.  */
17425b3c049e70834cf33790a28643ab058b507b35cBen Cheng  return (nbkpts
17525b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  ?: (lowpc == (Dwarf_Addr) -1l ? 0
17625b3c049e70834cf33790a28643ab058b507b35cBen Cheng	      : search_range (lowpc, highpc, false, true))
17725b3c049e70834cf33790a28643ab058b507b35cBen Cheng	  ?: entrypc_bkpt ());
17825b3c049e70834cf33790a28643ab058b507b35cBen Cheng}
179