src/mc/mc_location.h

   1 /* Copyright (c) 2004-2015. The SimGrid Team.
   2  * All rights reserved.                                                     */
   3
   4 /* This program is free software; you can redistribute it and/or modify it
   5  * under the terms of the license (GNU LGPL) which comes with this package. */
   6
   7 #ifndef SIMGRID_MC_OBJECT_LOCATION_H
   8 #define SIMGRID_MC_OBJECT_LOCATION_H
   9
  10 #include <stdint.h>
  11
  12 #include <vector>
  13
  14 #include <libunwind.h>
  15 #include <dwarf.h>
  16 #include <elfutils/libdw.h>
  17
  18 #include <simgrid_config.h>
  19 #include "mc_base.h"
  20 #include "mc_forward.hpp"
  21 #include "mc/AddressSpace.hpp"
  22 #include "mc/DwarfExpression.hpp"
  23
  24 namespace simgrid {
  25 namespace mc {
  26
  27
  28 /** \brief A DWARF expression with optional validity contraints */
  29 class LocationListEntry {
  30 public:
  31   simgrid::dwarf::DwarfExpression expression;
  32   void* lowpc, *highpc;
  33
  34   LocationListEntry() : lowpc(nullptr), highpc(nullptr) {}
  35
  36   bool valid_for_ip(unw_word_t ip)
  37   {
  38     return (this->lowpc == nullptr && this->highpc == nullptr)
  39         || (ip >= (unw_word_t) this->lowpc
  40             && ip < (unw_word_t) this->highpc);
  41   }
  42 };
  43
  44 typedef std::vector<LocationListEntry> LocationList;
  45
  46 }
  47 }
  48
  49 SG_BEGIN_DECL()
  50
  51 /** A location is either a location in memory of a register location
  52  *
  53  *  Usage:
  54  *
  55  *    * mc_dwarf_resolve_locations or mc_dwarf_resolve_location is used
  56  *      to find the location of a given location expression or location list;
  57  *
  58  *    * mc_get_location_type MUST be used to find the location type;
  59  *
  60  *    * for MC_LOCATION_TYPE_ADDRESS, memory_address is the resulting address
  61  *
  62  *    * for MC_LOCATION_TYPE_REGISTER, unw_get_reg(l.cursor, l.register_id, value)
  63  *        and unw_get_reg(l.cursor, l.register_id, value) can be used to read/write
  64  *        the value.
  65  *  </ul>
  66  */
  67 typedef struct s_mc_location {
  68   void* memory_location;
  69   unw_cursor_t* cursor;
  70   int register_id;
  71 } s_mc_location_t, *mc_location_t;
  72
  73 /** Type of a given location
  74  *
  75  *  Use `mc_get_location_type(location)` to find the type.
  76  * */
  77 typedef enum mc_location_type {
  78   MC_LOCATION_TYPE_ADDRESS,
  79   MC_LOCATION_TYPE_REGISTER
  80 } mc_location_type;
  81
  82 /** Find the type of a location */
  83 static inline __attribute__ ((always_inline))
  84 enum mc_location_type mc_get_location_type(mc_location_t location) {
  85   if (location->cursor) {
  86     return MC_LOCATION_TYPE_REGISTER;
  87   } else {
  88     return MC_LOCATION_TYPE_ADDRESS;
  89   }
  90 }
  91
  92 SG_END_DECL()
  93
  94 namespace simgrid {
  95 namespace dwarf {
  96
  97 XBT_PRIVATE void resolve_location(
  98   mc_location_t location, simgrid::dwarf::DwarfExpression const& expression,
  99   simgrid::mc::ObjectInformation* object_info, unw_cursor_t* c,
 100   void* frame_pointer_address, simgrid::mc::AddressSpace* address_space,
 101   int process_index);
 102
 103 }
 104 }
 105
 106 SG_BEGIN_DECL()
 107
 108 void mc_dwarf_resolve_locations(
 109   mc_location_t location, simgrid::mc::LocationList* locations,
 110   simgrid::mc::ObjectInformation* object_info, unw_cursor_t* c,
 111   void* frame_pointer_address, simgrid::mc::AddressSpace* address_space,
 112   int process_index);
 113
 114 XBT_PRIVATE void mc_dwarf_location_list_init(
 115   simgrid::mc::LocationList*, simgrid::mc::ObjectInformation* info, Dwarf_Die* die,
 116   Dwarf_Attribute* attr);
 117
 118 void* mc_find_frame_base(
 119   simgrid::mc::Frame* frame, simgrid::mc::ObjectInformation* object_info, unw_cursor_t* unw_cursor);
 120
 121 SG_END_DECL()
 122
 123 #endif