X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/997b91c0561be6db592ffbba36e6e65f0a661634..a4ff507efa9c473f29ade8357ce148274fbd1e97:/src/mc/mc_dwarf.c

diff --git a/src/mc/mc_dwarf.c b/src/mc/mc_dwarf.c
index 195cce2dfb..871e55b60c 100644
--- a/src/mc/mc_dwarf.c
+++ b/src/mc/mc_dwarf.c
@@ -1,6 +1,5 @@
 /* Copyright (c) 2008-2013. The SimGrid Team.
  * All rights reserved.                                                     */
-
 /* This program is free software; you can redistribute it and/or modify it
  * under the terms of the license (GNU LGPL) which comes with this package. */
 
@@ -20,78 +19,225 @@ XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_dwarf, mc, "DWARF processing");
 /** \brief The default DW_TAG_lower_bound for a given DW_AT_language.
  *
  *  The default for a given language is defined in the DWARF spec.
+ *
+ *  \param language consant as defined by the DWARf spec
  */
 static uint64_t MC_dwarf_default_lower_bound(int lang);
 
+/** \brief Computes the the element_count of a DW_TAG_enumeration_type DIE
+ *
+ * This is the number of elements in a given array dimension.
+ *
+ * A reference of the compilation unit (DW_TAG_compile_unit) is
+ * needed because the default lower bound (when there is no DW_AT_lower_bound)
+ * depends of the language of the compilation unit (DW_AT_language).
+ *
+ * \param die  DIE for the DW_TAG_enumeration_type or DW_TAG_subrange_type
+ * \param unit DIE of the DW_TAG_compile_unit
+ */
 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit);
 
-/** \brief Computes the number of elements of a given DW_TAG_array_type
+/** \brief Computes the number of elements of a given DW_TAG_array_type.
  *
+ * \param die DIE for the DW_TAG_array_type
  */
 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit);
 
-/** \brief Checks if a given tag is a (known) type tag.
+/** \brief Process a DIE
+ *
+ *  \param info the resulting object fot the library/binary file (output)
+ *  \param die  the current DIE
+ *  \param unit the DIE of the compile unit of the current DIE
+ *  \param frame containg frame if any
+ */
+static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
+
+/** \brief Process a type DIE
  */
-static int MC_dwarf_tag_type(int tag);
-static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit);
-static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit);
-static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit);
-static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit);
-static Dwarf_Die* MC_dwarf_resolve_die(Dwarf_Die* die, int attribute);
+static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
 
+/** \brief Calls MC_dwarf_handle_die on all childrend of the given die
+ *
+ *  \param info the resulting object fot the library/binary file (output)
+ *  \param die  the current DIE
+ *  \param unit the DIE of the compile unit of the current DIE
+ *  \param frame containg frame if any
+ */
+static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
+
+/** \brief Handle a variable (DW_TAG_variable or other)
+ *
+ *  \param info the resulting object fot the library/binary file (output)
+ *  \param die  the current DIE
+ *  \param unit the DIE of the compile unit of the current DIE
+ *  \param frame containg frame if any
+ */
+static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace);
+
+/** \brief Get the DW_TAG_type of the DIE
+ *
+ *  \param die DIE
+ *  \return DW_TAG_type attribute as a new string (NULL if none)
+ */
+static char* MC_dwarf_at_type(Dwarf_Die* die);
+
+/** \brief Get the name of an attribute (DW_AT_*) from its code
+ *
+ *  \param attr attribute code (see the DWARF specification)
+ *  \return name of the attribute
+ */
 const char* MC_dwarf_attrname(int attr) {
   switch (attr) {
 #include "mc_dwarf_attrnames.h"
   default:
-    return "DW_AT_unkown";
+    return "DW_AT_unknown";
   }
 }
 
+/** \brief Get the name of a dwarf tag (DW_TAG_*) from its code
+ *
+ *  \param tag tag code (see the DWARF specification)
+ *  \return name of the tag
+ */
 const char* MC_dwarf_tagname(int tag) {
   switch (tag) {
 #include "mc_dwarf_tagnames.h"
   case DW_TAG_invalid:
     return "DW_TAG_invalid";
   default:
-    return "DW_TAG_unkown";
+    return "DW_TAG_unknown";
   }
 }
 
-static inline const char* MC_dwarf_die_tagname(Dwarf_Die* die) {
-  return MC_dwarf_tagname(dwarf_tag(die));
+/** \brief A class of DWARF tags (DW_TAG_*)
+ */
+typedef enum mc_tag_class {
+  mc_tag_unknown,
+  mc_tag_type,
+  mc_tag_subprogram,
+  mc_tag_variable,
+  mc_tag_scope,
+  mc_tag_namespace
+} mc_tag_class;
+
+static mc_tag_class MC_dwarf_tag_classify(int tag) {
+  switch (tag) {
+
+    case DW_TAG_array_type:
+    case DW_TAG_class_type:
+    case DW_TAG_enumeration_type:
+    case DW_TAG_typedef:
+    case DW_TAG_pointer_type:
+    case DW_TAG_reference_type:
+    case DW_TAG_rvalue_reference_type:
+    case DW_TAG_string_type:
+    case DW_TAG_structure_type:
+    case DW_TAG_subroutine_type:
+    case DW_TAG_union_type:
+    case DW_TAG_ptr_to_member_type:
+    case DW_TAG_set_type:
+    case DW_TAG_subrange_type:
+    case DW_TAG_base_type:
+    case DW_TAG_const_type:
+    case DW_TAG_file_type:
+    case DW_TAG_packed_type:
+    case DW_TAG_volatile_type:
+    case DW_TAG_restrict_type:
+    case DW_TAG_interface_type:
+    case DW_TAG_unspecified_type:
+    case DW_TAG_mutable_type:
+    case DW_TAG_shared_type:
+      return mc_tag_type;
+
+    case DW_TAG_subprogram:
+      return mc_tag_subprogram;
+
+    case DW_TAG_variable:
+    case DW_TAG_formal_parameter:
+      return mc_tag_variable;
+
+    case DW_TAG_lexical_block:
+    case DW_TAG_try_block:
+    case DW_TAG_inlined_subroutine:
+      return mc_tag_scope;
+
+    case DW_TAG_namespace:
+      return mc_tag_namespace;
+
+    default:
+      return mc_tag_unknown;
+
+  }
 }
 
-static int MC_dwarf_tag_type(int tag) {
-  switch(tag) {
-  case DW_TAG_array_type:
-  case DW_TAG_class_type:
-  case DW_TAG_enumeration_type:
-  case DW_TAG_typedef:
-  case DW_TAG_pointer_type:
-  case DW_TAG_string_type:
-  case DW_TAG_structure_type:
-  case DW_TAG_subroutine_type:
-  case DW_TAG_union_type:
-  case DW_TAG_ptr_to_member_type:
-  case DW_TAG_set_type:
-  case DW_TAG_subrange_type:
-  case DW_TAG_base_type:
-  case DW_TAG_const_type:
-  case DW_TAG_file_type:
-  case DW_TAG_packed_type:
-  case DW_TAG_volatile_type:
-  case DW_TAG_restrict_type:
-  case DW_TAG_interface_type:
-  case DW_TAG_unspecified_type:
-  case DW_TAG_mutable_type:
-  case DW_TAG_shared_type:
-  case DW_TAG_rvalue_reference_type:
-    return 1;
+#define MC_DW_CLASS_UNKNOWN 0
+#define MC_DW_CLASS_ADDRESS 1   // Location in the address space of the program
+#define MC_DW_CLASS_BLOCK 2     // Arbitrary block of bytes
+#define MC_DW_CLASS_CONSTANT 3
+#define MC_DW_CLASS_STRING 3    // String
+#define MC_DW_CLASS_FLAG 4      // Boolean
+#define MC_DW_CLASS_REFERENCE 5 // Reference to another DIE
+#define MC_DW_CLASS_EXPRLOC 6   // DWARF expression/location description
+#define MC_DW_CLASS_LINEPTR 7
+#define MC_DW_CLASS_LOCLISTPTR 8
+#define MC_DW_CLASS_MACPTR 9
+#define MC_DW_CLASS_RANGELISTPTR 10
+
+static int MC_dwarf_form_get_class(int form) {
+  switch(form) {
+  case DW_FORM_addr:
+    return MC_DW_CLASS_ADDRESS;
+  case DW_FORM_block2:
+  case DW_FORM_block4:
+  case DW_FORM_block:
+  case DW_FORM_block1:
+    return MC_DW_CLASS_BLOCK;
+  case DW_FORM_data1:
+  case DW_FORM_data2:
+  case DW_FORM_data4:
+  case DW_FORM_data8:
+  case DW_FORM_udata:
+  case DW_FORM_sdata:
+    return MC_DW_CLASS_CONSTANT;
+  case DW_FORM_string:
+  case DW_FORM_strp:
+    return MC_DW_CLASS_STRING;
+  case DW_FORM_ref_addr:
+  case DW_FORM_ref1:
+  case DW_FORM_ref2:
+  case DW_FORM_ref4:
+  case DW_FORM_ref8:
+  case DW_FORM_ref_udata:
+    return MC_DW_CLASS_REFERENCE;
+  case DW_FORM_flag:
+  case DW_FORM_flag_present:
+    return MC_DW_CLASS_FLAG;
+  case DW_FORM_exprloc:
+    return MC_DW_CLASS_EXPRLOC;
+  // TODO sec offset
+  // TODO indirect
   default:
-    return 0;
+    return MC_DW_CLASS_UNKNOWN;
   }
 }
 
+/** \brief Get the name of the tag of a given DIE
+ *
+ *  \param die DIE
+ *  \return name of the tag of this DIE
+ */
+static inline const char* MC_dwarf_die_tagname(Dwarf_Die* die) {
+  return MC_dwarf_tagname(dwarf_tag(die));
+}
+
+// ***** Attributes
+
+/** \brief Get an attribute of a given DIE as a string
+ *
+ *  \param the DIE
+ *  \param attribute attribute
+ *  \return value of the given attribute of the given DIE
+ */
 static const char* MC_dwarf_attr_string(Dwarf_Die* die, int attribute) {
   Dwarf_Attribute attr;
   if (!dwarf_attr_integrate(die, attribute, &attr)) {
@@ -101,7 +247,20 @@ static const char* MC_dwarf_attr_string(Dwarf_Die* die, int attribute) {
   }
 }
 
-// Return a new string for the type (NULL if none)
+/** \brief Get the linkage name of a DIE.
+ *
+ *  Use either DW_AT_linkage_name or DW_AR_MIPS_linkage_name.
+ *
+ *  \param DIE
+ *  \return linkage name of the given DIE (or NULL)
+ * */
+static const char* MC_dwarf_at_linkage_name(Dwarf_Die* die) {
+  const char* name = MC_dwarf_attr_string(die, DW_AT_linkage_name);
+  if (!name)
+    name = MC_dwarf_attr_string(die, DW_AT_MIPS_linkage_name);
+  return name;
+}
+
 static char* MC_dwarf_at_type(Dwarf_Die* die) {
   Dwarf_Attribute attr;
   if (dwarf_hasattr_integrate(die, DW_AT_type)) {
@@ -116,12 +275,38 @@ static char* MC_dwarf_at_type(Dwarf_Die* die) {
   else return NULL;
 }
 
+static uint64_t MC_dwarf_attr_addr(Dwarf_Die* die, int attribute) {
+  Dwarf_Attribute attr;
+  if(dwarf_attr_integrate(die, attribute, &attr)==NULL)
+    return 0;
+  Dwarf_Addr value;
+  if (dwarf_formaddr(&attr, &value) == 0)
+    return (uint64_t) value;
+  else
+    return 0;
+}
+
 static uint64_t MC_dwarf_attr_uint(Dwarf_Die* die, int attribute, uint64_t default_value) {
   Dwarf_Attribute attr;
+  if (dwarf_attr_integrate(die, attribute, &attr)==NULL)
+    return default_value;
   Dwarf_Word value;
   return dwarf_formudata(dwarf_attr_integrate(die, attribute, &attr), &value) == 0 ? (uint64_t) value : default_value;
 }
 
+static bool MC_dwarf_attr_flag(Dwarf_Die* die, int attribute, int integrate) {
+  Dwarf_Attribute attr;
+  if ((integrate ? dwarf_attr_integrate(die, attribute, &attr)
+                    : dwarf_attr(die, attribute, &attr))==0)
+    return false;
+
+  bool result;
+  if (dwarf_formflag(&attr, &result))
+    xbt_die("Unexpected form for attribute %s",
+      MC_dwarf_attrname(attribute));
+  return result;
+}
+
 static uint64_t MC_dwarf_default_lower_bound(int lang) {
   switch(lang) {
   case DW_LANG_C:
@@ -153,12 +338,15 @@ static uint64_t MC_dwarf_default_lower_bound(int lang) {
 }
 
 static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
+  xbt_assert(dwarf_tag(die)==DW_TAG_enumeration_type ||dwarf_tag(die)==DW_TAG_subrange_type,
+      "MC_dwarf_subrange_element_count called with DIE of type %s", MC_dwarf_die_tagname(die));
+
   // Use DW_TAG_count if present:
   if (dwarf_hasattr_integrate(die, DW_AT_count)) {
     return MC_dwarf_attr_uint(die, DW_AT_count, 0);
   }
 
-  // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound:
+  // Otherwise compute DW_TAG_upper_bound-DW_TAG_lower_bound + 1:
 
   if (!dwarf_hasattr_integrate(die, DW_AT_upper_bound)) {
 	// This is not really 0, but the code expects this (we do not know):
@@ -172,7 +360,7 @@ static uint64_t MC_dwarf_subrange_element_count(Dwarf_Die* die, Dwarf_Die* unit)
   } else {
 	lower_bound = MC_dwarf_default_lower_bound(dwarf_srclang(unit));
   }
-  return upper_bound - lower_bound;
+  return upper_bound - lower_bound + 1;
 }
 
 static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
@@ -191,6 +379,8 @@ static uint64_t MC_dwarf_array_element_count(Dwarf_Die* die, Dwarf_Die* unit) {
   return result;
 }
 
+// ***** dw_type_t
+
 static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member, Dwarf_Die* child) {
   if (dwarf_hasattr(child, DW_AT_data_bit_offset)) {
     xbt_die("Can't groke DW_AT_data_bit_offset.");
@@ -208,11 +398,13 @@ static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member, Dwar
 
   Dwarf_Attribute attr;
   dwarf_attr_integrate(child, DW_AT_data_member_location, &attr);
-  switch (dwarf_whatform(&attr)) {
-
-  case DW_FORM_exprloc:
+  int form = dwarf_whatform(&attr);
+  int klass = MC_dwarf_form_get_class(form);
+  switch (klass) {
+  case MC_DW_CLASS_EXPRLOC:
+  case MC_DW_CLASS_BLOCK:
+    // Location expression:
     {
-      //TODO, location can be an integer as well
       Dwarf_Op* expr;
       size_t len;
       if (dwarf_getlocation(&attr, &expr, &len)) {
@@ -224,28 +416,34 @@ static void MC_dwarf_fill_member_location(dw_type_t type, dw_type_t member, Dwar
       if (len==1 && expr[0].atom == DW_OP_plus_uconst) {
         member->offset =  expr[0].number;
       } else {
-        xbt_die("Can't groke this location expression yet. %i %i",
-          len==1 , expr[0].atom == DW_OP_plus_uconst);
+        mc_dwarf_expression_init(&member->location, len, expr);
       }
       break;
     }
-  case DW_FORM_data1:
-  case DW_FORM_data2:
-  case DW_FORM_data4:
-  case DW_FORM_data8:
-  case DW_FORM_sdata:
-  case DW_FORM_udata:
+  case MC_DW_CLASS_CONSTANT:
+    // Offset from the base address of the object:
     {
       Dwarf_Word offset;
       if (!dwarf_formudata(&attr, &offset))
         member->offset = offset;
       else
-        xbt_die("Cannot get DW_AT_data_member_%s location <%p>%s",
+        xbt_die("Cannot get %s location <%p>%s",
           MC_dwarf_attr_string(child, DW_AT_name),
           type->id, type->name);
       break;
     }
+  case MC_DW_CLASS_LOCLISTPTR:
+    // Reference to a location list:
+    // TODO
+  case MC_DW_CLASS_REFERENCE:
+    // It's supposed to be possible in DWARF2 but I couldn't find its semantic
+    // in the spec.
+  default:
+    xbt_die(
+      "Can't handle form class (%i) / form 0x%x as DW_AT_member_location",
+      klass, form);
   }
+
 }
 
 static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_type_t type) {
@@ -254,11 +452,23 @@ static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die* die, Dwarf_Di
   xbt_assert(!type->members);
   type->members = xbt_dynar_new(sizeof(dw_type_t), (void(*)(void*))dw_type_free);
   for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
-    if (dwarf_tag(&child)==DW_TAG_member) {
+    int tag = dwarf_tag(&child);
+    if (tag==DW_TAG_member || tag==DW_TAG_inheritance) {
+
+      // Skip declarations:
+      if (MC_dwarf_attr_flag(&child, DW_AT_declaration, false))
+        continue;
+
+      // Skip compile time constants:
+      if(dwarf_hasattr(&child, DW_AT_const_value))
+        continue;
+
       // TODO, we should use another type (because is is not a type but a member)
       dw_type_t member = xbt_new0(s_dw_type_t, 1);
-      member->type = -1;
-      member->id = NULL;
+      member->type = tag;
+
+      // Global Offset:
+      member->id = (void *) dwarf_dieoffset(&child);
 
       const char* name = MC_dwarf_attr_string(&child, DW_AT_name);
       if(name)
@@ -279,12 +489,23 @@ static void MC_dwarf_add_members(mc_object_info_t info, Dwarf_Die* die, Dwarf_Di
 
       MC_dwarf_fill_member_location(type, member, &child);
 
+      if (!member->dw_type_id) {
+        xbt_die("Missing type for member %s of <%p>%s", member->name, type->id, type->name);
+      }
+
       xbt_dynar_push(type->members, &member);
     }
   }
 }
 
-static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit) {
+/** \brief Create a MC type object from a DIE
+ *
+ *  \param info current object info object
+ *  \param DIE (for a given type);
+ *  \param unit compilation unit of the current DIE
+ *  \return MC representation of the type
+ */
+static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
 
   dw_type_t type = xbt_new0(s_dw_type_t, 1);
   type->type = -1;
@@ -302,9 +523,24 @@ static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die* die, Dwa
   // Global Offset
   type->id = (void *) dwarf_dieoffset(die);
 
+  const char* prefix = "";
+  switch (type->type) {
+  case DW_TAG_structure_type:
+    prefix = "struct ";
+    break;
+  case DW_TAG_union_type:
+    prefix = "union ";
+    break;
+  case DW_TAG_class_type:
+    prefix = "class ";
+    break;
+  default:
+    prefix = "";
+  }
+
   const char* name = MC_dwarf_attr_string(die, DW_AT_name);
   if (name!=NULL) {
-	type->name = xbt_strdup(name);
+    type->name = namespace ? bprintf("%s%s::%s", prefix, namespace, name) : bprintf("%s%s", prefix, name);
   }
 
   XBT_DEBUG("Processing type <%p>%s", type->id, type->name);
@@ -337,44 +573,236 @@ static dw_type_t MC_dwarf_die_to_type(mc_object_info_t info, Dwarf_Die* die, Dwa
   case DW_TAG_union_type:
   case DW_TAG_class_type:
 	  MC_dwarf_add_members(info, die, unit, type);
+	  char* new_namespace = namespace == NULL ? xbt_strdup(type->name)
+	    : bprintf("%s::%s", namespace, name);
+	  MC_dwarf_handle_children(info, die, unit, frame, new_namespace);
+	  free(new_namespace);
+	  break;
   }
 
   return type;
 }
 
-static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit) {
-  dw_type_t type = MC_dwarf_die_to_type(info, die, unit);
+static void MC_dwarf_handle_type_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
+  dw_type_t type = MC_dwarf_die_to_type(info, die, unit, frame, namespace);
 
   char* key = bprintf("%" PRIx64, (uint64_t) type->id);
   xbt_dict_set(info->types, key, type, NULL);
+
+  if(type->name && type->byte_size!=0) {
+    xbt_dict_set(info->full_types_by_name, type->name, type, NULL);
+  }
+}
+
+static int mc_anonymous_variable_index = 0;
+
+static dw_variable_t MC_die_to_variable(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
+  // Skip declarations:
+  if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
+    return NULL;
+
+  // Skip compile time constants:
+  if(dwarf_hasattr(die, DW_AT_const_value))
+    return NULL;
+
+  Dwarf_Attribute attr_location;
+  if (dwarf_attr(die, DW_AT_location, &attr_location)==NULL) {
+    // No location: do not add it ?
+    return NULL;
+  }
+
+  dw_variable_t variable = xbt_new0(s_dw_variable_t, 1);
+  variable->dwarf_offset = dwarf_dieoffset(die);
+  variable->global = frame == NULL; // Can be override base on DW_AT_location
+
+  const char* name = MC_dwarf_attr_string(die, DW_AT_name);
+  variable->name = xbt_strdup(name);
+
+  variable->type_origin = MC_dwarf_at_type(die);
+
+  int form = dwarf_whatform(&attr_location);
+  int klass = form == DW_FORM_sec_offset ? MC_DW_CLASS_CONSTANT : MC_dwarf_form_get_class(form);
+  switch (klass) {
+  case MC_DW_CLASS_EXPRLOC:
+  case MC_DW_CLASS_BLOCK:
+    // Location expression:
+    {
+      Dwarf_Op* expr;
+      size_t len;
+      if (dwarf_getlocation(&attr_location, &expr, &len)) {
+        xbt_die(
+          "Could not read location expression in DW_AT_location of variable <%p>%s",
+          (void*) variable->dwarf_offset, variable->name);
+      }
+
+      if (len==1 && expr[0].atom == DW_OP_addr) {
+        variable->global = 1;
+        Dwarf_Off offset = expr[0].number;
+        // TODO, Why is this different base on the object?
+        Dwarf_Off base = strcmp(info->file_name, xbt_binary_name) !=0 ? (Dwarf_Off) info->start_exec : 0;
+        variable->address = (void*) (base + offset);
+      } else {
+        mc_dwarf_location_list_init_from_expression(&variable->locations, len, expr);
+      }
+
+      break;
+    }
+  case MC_DW_CLASS_LOCLISTPTR:
+  case MC_DW_CLASS_CONSTANT:
+    // Reference to location list:
+    mc_dwarf_location_list_init(&variable->locations, info, die, &attr_location);
+    break;
+  default:
+    xbt_die("Unexpected form 0x%x (%i), class 0x%x (%i) list for location in <%p>%s",
+      form, form, klass, klass, (void*) variable->dwarf_offset, variable->name);
+  }
+
+  // Handle start_scope:
+  if (dwarf_hasattr(die, DW_AT_start_scope)) {
+    Dwarf_Attribute attr;
+    dwarf_attr(die, DW_AT_start_scope, &attr);
+    int form  = dwarf_whatform(&attr);
+    int klass = MC_dwarf_form_get_class(form);
+    switch(klass) {
+    case MC_DW_CLASS_CONSTANT:
+    {
+      Dwarf_Word value;
+      variable->start_scope = dwarf_formudata(&attr, &value) == 0 ? (size_t) value : 0;
+      break;
+    }
+    default:
+      xbt_die("Unhandled form 0x%x, class 0x%X for DW_AT_start_scope of variable %s",
+        form, klass, name==NULL ? "?" : name);
+    }
+  }
+
+  if(namespace && variable->global) {
+    char* old_name = variable->name;
+    variable->name = bprintf("%s::%s", namespace, old_name);
+    free(old_name);
+  }
+
+  // The current code needs a variable name,
+  // generate a fake one:
+  if(!variable->name) {
+    variable->name = bprintf("@anonymous#%i", mc_anonymous_variable_index++);
+  }
+
+  return variable;
+}
+
+static void MC_dwarf_handle_variable_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
+  dw_variable_t variable = MC_die_to_variable(info, die, unit, frame, namespace);
+  if(variable==NULL)
+      return;
+  MC_dwarf_register_variable(info, frame, variable);
+}
+
+static void MC_dwarf_handle_subprogram_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t parent_frame, const char* namespace) {
+
+  // (Template) Subprogram declaration:
+  if (MC_dwarf_attr_flag(die, DW_AT_declaration, false))
+    return;
+
+  // Abstract inline instance (DW_AT_inline != DW_INL_not_inlined):
+  if (dwarf_func_inline(die))
+    return;
+
+  // This is probably not a concrete instance:
+  // DWARF2/3 and DWARF4 do not agree on the meaning of DW_INL_not_inlined.
+  // For DWARF2/3, the subprogram is abstract.
+  // For DARF4, the subprogram is not abstract.
+  if(!dwarf_hasattr_integrate(die, DW_AT_low_pc))
+    return;
+
+  dw_frame_t frame = xbt_new0(s_dw_frame_t, 1);
+
+  frame->start = dwarf_dieoffset(die);
+
+  const char* name = MC_dwarf_attr_string(die, DW_AT_name);
+  frame->name = namespace ? bprintf("%s::%s", namespace, name) : xbt_strdup(name);
+
+  // This is the base address for DWARF addresses.
+  // Relocated addresses are offset from this base address.
+  // See DWARF4 spec 7.5
+  void* base = info->flags & MC_OBJECT_INFO_EXECUTABLE ? 0 : MC_object_base_address(info);
+
+  // Variables are filled in the (recursive) call of MC_dwarf_handle_children:
+  frame->variables = xbt_dynar_new(sizeof(dw_variable_t), dw_variable_free_voidp);
+  frame->high_pc = ((char*) base) + MC_dwarf_attr_addr(die, DW_AT_high_pc);
+  frame->low_pc = ((char*) base) + MC_dwarf_attr_addr(die, DW_AT_low_pc);
+
+  if(frame->high_pc==0 || frame->low_pc==0)
+    xbt_die("Could not resolve highpc/lowpc");
+
+  Dwarf_Attribute attr_frame_base;
+  if (!dwarf_attr_integrate(die, DW_AT_frame_base, &attr_frame_base))
+    xbt_die("Coult not find DW_AT_frame_base for subprogram %s 0x%lx", frame->name, frame->start);
+  mc_dwarf_location_list_init(&frame->frame_base, info, die, &attr_frame_base);
+
+  frame->end = -1; // This one is now useless:
+
+  // Register it:
+  xbt_dynar_push(info->subprograms, &frame);
+
+  // Handle children:
+  MC_dwarf_handle_children(info, die, unit, frame, namespace);
 }
 
+static void mc_dwarf_handle_namespace_die(
+    mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
+  const char* name = MC_dwarf_attr_string(die, DW_AT_name);
+  if(frame)
+    xbt_die("Unexpected namespace in a subprogram");
+  char* new_namespace = namespace == NULL ? xbt_strdup(name)
+    : bprintf("%s::%s", namespace, name);
+  MC_dwarf_handle_children(info, die, unit, frame, new_namespace);
+}
 
-static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit) {
+static void MC_dwarf_handle_children(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
   Dwarf_Die child;
   int res;
   for (res=dwarf_child(die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
-    MC_dwarf_handle_die(info, &child, unit);
+    MC_dwarf_handle_die(info, &child, unit, frame, namespace);
   }
 }
 
-static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit) {
-	int tag = dwarf_tag(die);
+static void MC_dwarf_handle_die(mc_object_info_t info, Dwarf_Die* die, Dwarf_Die* unit, dw_frame_t frame, const char* namespace) {
+  int tag = dwarf_tag(die);
+  mc_tag_class klass = MC_dwarf_tag_classify(tag);
+  switch (klass) {
 
-	// Register types:
-	if (MC_dwarf_tag_type(tag))
-		MC_dwarf_handle_type_die(info, die, unit);
+    // Type:
+    case mc_tag_type:
+      MC_dwarf_handle_type_die(info, die, unit, frame, namespace);
+      break;
 
-	// Other tag-specific handling:
-	else switch(tag) {
+    // Program:
+    case mc_tag_subprogram:
+      MC_dwarf_handle_subprogram_die(info, die, unit, frame, namespace);
+      return;
 
-	}
+    // Variable:
+    case mc_tag_variable:
+      MC_dwarf_handle_variable_die(info, die, unit, frame, namespace);
+      break;
+
+    // Scope:
+    case mc_tag_scope:
+      // TODO
+      break;
+
+    case mc_tag_namespace:
+      mc_dwarf_handle_namespace_die(info, die, unit, frame, namespace);
+      break;
 
-	// Recursive processing od children DIE:
-	MC_dwarf_handle_children(info, die, unit);
+    default:
+      break;
+
+  }
 }
 
-void MC_dwarf_get_variables_libdw(mc_object_info_t info) {
+void MC_dwarf_get_variables(mc_object_info_t info) {
   int fd = open(info->file_name, O_RDONLY);
   if (fd<0) {
     xbt_die("Could not open file %s", info->file_name);
@@ -388,9 +816,14 @@ void MC_dwarf_get_variables_libdw(mc_object_info_t info) {
   Dwarf_Off next_offset = 0;
   size_t length;
   while (dwarf_nextcu (dwarf, offset, &next_offset, &length, NULL, NULL, NULL) == 0) {
-    Dwarf_Die die;
-    if(dwarf_offdie(dwarf, offset+length, &die)!=NULL) {
-      MC_dwarf_handle_die(info, &die, &die);
+    Dwarf_Die unit_die;
+
+    if(dwarf_offdie(dwarf, offset+length, &unit_die)!=NULL) {
+      Dwarf_Die child;
+      int res;
+      for (res=dwarf_child(&unit_die, &child); res==0; res=dwarf_siblingof(&child,&child)) {
+        MC_dwarf_handle_die(info, &child, &unit_die, NULL, NULL);
+      }
     }
     offset = next_offset;
   }