Line data    Source code

       1             : /* Return associated attribute for DW_OP_GNU_implicit_pointer.
       2             :    Copyright (C) 2010, 2017 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 "libdwP.h"
      34             : #include <dwarf.h>
      35             : 
      36             : 
      37             : static unsigned char empty_exprloc = 0;
      38             : static Dwarf_CU empty_cu = { .startp = &empty_exprloc,
      39             :                              .endp = &empty_exprloc + 1 };
      40             : 
      41             : void
      42             : internal_function
      43          12 : __libdw_empty_loc_attr (Dwarf_Attribute *attr)
      44             : {
      45          12 :   attr->code = DW_AT_location;
      46          12 :   attr->form = DW_FORM_exprloc;
      47          12 :   attr->valp = &empty_exprloc;
      48          12 :   attr->cu = &empty_cu;
      49          12 : }
      50             : 
      51             : int
      52        6938 : dwarf_getlocation_implicit_pointer (Dwarf_Attribute *attr, const Dwarf_Op *op,
      53             :                                     Dwarf_Attribute *result)
      54             : {
      55        6938 :   if (attr == NULL)
      56             :     return -1;
      57             : 
      58        6938 :   if (unlikely (op->atom != DW_OP_implicit_pointer
      59             :                 && op->atom != DW_OP_GNU_implicit_pointer))
      60             :     {
      61           0 :       __libdw_seterrno (DWARF_E_INVALID_ACCESS);
      62           0 :       return -1;
      63             :     }
      64             : 
      65             :   Dwarf_Die die;
      66        6938 :   if (__libdw_offdie (attr->cu->dbg, op->number, &die,
      67        6938 :                       ISV4TU(attr->cu)) == NULL)
      68             :     return -1;
      69             : 
      70        6938 :   if (INTUSE(dwarf_attr) (&die, DW_AT_location, result) == NULL
      71           6 :       && INTUSE(dwarf_attr) (&die, DW_AT_const_value, result) == NULL)
      72             :     {
      73           6 :       __libdw_empty_loc_attr (result);
      74           6 :       return 0;
      75             :     }
      76             : 
      77             :   return 0;
      78             : }