X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/89d98a56977c70b61c8dba09f5c5136e73784339..29b2bf945239b1950c277f4afff78e8ea327000a:/src/mc/mc_compare.c

diff --git a/src/mc/mc_compare.c b/src/mc/mc_compare.c
index 85c2901c94..7042a5854b 100644
--- a/src/mc/mc_compare.c
+++ b/src/mc/mc_compare.c
@@ -1,87 +1,70 @@
-/* Copyright (c) 2012-2013 Da SimGrid Team. All rights reserved.            */
+/* Copyright (c) 2012-2014. 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. */
 
+#include <inttypes.h>
+
 #include "mc_private.h"
 
 #include "xbt/mmalloc.h"
+#include "xbt/mmalloc/mmprivate.h"
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_compare, mc,
                                 "Logging specific to mc_compare");
 
-typedef struct s_pointers_pair{
+typedef struct s_pointers_pair {
   void *p1;
   void *p2;
-}s_pointers_pair_t, *pointers_pair_t;
+} s_pointers_pair_t, *pointers_pair_t;
 
 __thread xbt_dynar_t compared_pointers;
 
 /************************** Free functions ****************************/
 /********************************************************************/
 
-static void stack_region_free(stack_region_t s){
-  if(s){
+static void stack_region_free(stack_region_t s)
+{
+  if (s) {
     xbt_free(s->process_name);
     xbt_free(s);
   }
 }
 
-static void stack_region_free_voidp(void *s){
+static void stack_region_free_voidp(void *s)
+{
   stack_region_free((stack_region_t) * (void **) s);
 }
 
-static void pointers_pair_free(pointers_pair_t p){
+static void pointers_pair_free(pointers_pair_t p)
+{
   xbt_free(p);
 }
 
-static void pointers_pair_free_voidp(void *p){
-  pointers_pair_free((pointers_pair_t) * (void **)p);
+static void pointers_pair_free_voidp(void *p)
+{
+  pointers_pair_free((pointers_pair_t) * (void **) p);
 }
 
 /************************** Snapshot comparison *******************************/
 /******************************************************************************/
 
-static int already_compared_pointers(void *p1, void *p2){
-
-  if(xbt_dynar_is_empty(compared_pointers))
-    return -1;
-
-  unsigned int cursor = 0;
-  int start = 0;
-  int end = xbt_dynar_length(compared_pointers) - 1;
-  pointers_pair_t pair;
-
-  while(start <= end){
-    cursor = (start + end) / 2;
-    pair = (pointers_pair_t)xbt_dynar_get_as(compared_pointers, cursor, pointers_pair_t);
-    if(pair->p1 == p1){
-      if(pair->p2 == p2)
-        return 0;
-      else if(pair->p2 < p2)
-        start = cursor + 1;
-      else
-        end = cursor - 1;
-    }else if(pair->p1 < p1){
-      start = cursor + 1;
-    }else{
-      end = cursor - 1 ;
-    }
-  }
-
-  return -1;
-
-}
-
-static void add_compared_pointers(void *p1, void *p2){
+/** \brief Try to add a pair a compared pointers to the set of compared pointers
+ *
+ *  \result !=0 if the pointers were added (they were not in the set),
+ *      0 otherwise (they were already in the set)
+ */
+static int add_compared_pointers(void *p1, void *p2)
+{
 
   pointers_pair_t new_pair = xbt_new0(s_pointers_pair_t, 1);
   new_pair->p1 = p1;
   new_pair->p2 = p2;
-  
-  if(xbt_dynar_is_empty(compared_pointers)){
+
+  if (xbt_dynar_is_empty(compared_pointers)) {
     xbt_dynar_push(compared_pointers, &new_pair);
-    return;
+    return 1;
   }
 
   unsigned int cursor = 0;
@@ -89,190 +72,246 @@ static void add_compared_pointers(void *p1, void *p2){
   int end = xbt_dynar_length(compared_pointers) - 1;
   pointers_pair_t pair = NULL;
 
-  while(start <= end){
+  pointers_pair_t *p =
+      (pointers_pair_t *) xbt_dynar_get_ptr(compared_pointers, 0);
+
+  while (start <= end) {
     cursor = (start + end) / 2;
-    pair = (pointers_pair_t)xbt_dynar_get_as(compared_pointers, cursor, pointers_pair_t);
-    if(pair->p1 == p1){
-      if(pair->p2 == p2){
-        pointers_pair_free(new_pair);
-        return;
-      }else if(pair->p2 < p2)
-        start = cursor + 1;
-      else
-        end = cursor - 1;
-    }else if(pair->p1 < p1){
+    pair = p[cursor];
+    if (pair->p1 < p1) {
+      start = cursor + 1;
+    } else if (pair->p1 > p1) {
+      end = cursor - 1;
+    } else if (pair->p2 < p2) {
       start = cursor + 1;
-    }else{
-      end = cursor - 1 ;
+    } else if (pair->p2 > p2) {
+      end = cursor - 1;
+    } else {
+      pointers_pair_free(new_pair);
+      return 0;
     }
   }
 
-  if(pair->p1 == p1){
-    if(pair->p2 < p2)
-      xbt_dynar_insert_at(compared_pointers, cursor + 1, &new_pair);
-    else
-      xbt_dynar_insert_at(compared_pointers, cursor, &new_pair); 
-  }else{
-    if(pair->p1 < p1)
-      xbt_dynar_insert_at(compared_pointers, cursor + 1, &new_pair);
-    else
-      xbt_dynar_insert_at(compared_pointers, cursor, &new_pair);   
-  }
-
+  if (pair->p1 < p1)
+    xbt_dynar_insert_at(compared_pointers, cursor + 1, &new_pair);
+  else if (pair->p1 > p1)
+    xbt_dynar_insert_at(compared_pointers, cursor, &new_pair);
+  else if (pair->p2 < p2)
+    xbt_dynar_insert_at(compared_pointers, cursor + 1, &new_pair);
+  else if (pair->p2 > p2)
+    xbt_dynar_insert_at(compared_pointers, cursor, &new_pair);
+  else
+    xbt_die("Unrecheable");
+
+  return 1;
 }
 
-static int compare_areas_with_type(void *area1, void *area2, xbt_dict_t types, xbt_dict_t other_types, char *type_id, int region_size, int region_type, void *start_data, int pointer_level){
+static int compare_areas_with_type(void *area1, void *area2,
+                                   mc_snapshot_t snapshot1,
+                                   mc_snapshot_t snapshot2, dw_type_t type,
+                                   int region_size, int region_type,
+                                   void *start_data, int pointer_level)
+{
 
-  dw_type_t type = xbt_dict_get_or_null(types, type_id);;
   unsigned int cursor = 0;
   dw_type_t member, subtype, subsubtype;
-  int elm_size, i, res, switch_types = 0;
+  int elm_size, i, res;
   void *addr_pointed1, *addr_pointed2;
-  int pointed_area_size1, pointed_area_size2;
 
-  switch(type->type){
-  case e_dw_base_type:
-  case e_dw_enumeration_type:
-  case e_dw_union_type:
-    return (memcmp(area1, area2, type->size) != 0);
-    break;
-  case e_dw_typedef:
-  case e_dw_volatile_type:
-    return compare_areas_with_type(area1, area2, types, other_types, type->dw_type_id, region_size, region_type, start_data, pointer_level);
+  switch (type->type) {
+  case DW_TAG_unspecified_type:
+    return 1;
+
+  case DW_TAG_base_type:
+  case DW_TAG_enumeration_type:
+  case DW_TAG_union_type:
+    return (memcmp(area1, area2, type->byte_size) != 0);
     break;
-  case e_dw_const_type: /* Const variable cannot be modified */
-    return -1;
+  case DW_TAG_typedef:
+  case DW_TAG_volatile_type:
+  case DW_TAG_const_type:
+    return compare_areas_with_type(area1, area2, snapshot1, snapshot2,
+                                   type->subtype, region_size, region_type,
+                                   start_data, pointer_level);
     break;
-  case e_dw_array_type:
-    subtype = xbt_dict_get_or_null(types, type->dw_type_id);
-    switch(subtype->type){
-    case e_dw_base_type:
-    case e_dw_enumeration_type:
-    case e_dw_pointer_type:
-    case e_dw_structure_type:
-    case e_dw_union_type:
-      if(subtype->size == 0){ /*declaration of the type, need the complete description */
-        subtype = xbt_dict_get_or_null(types, get_type_description(types, subtype->name));
-        if(subtype == NULL){
-          subtype = xbt_dict_get_or_null(other_types, get_type_description(other_types, subtype->name));
-          switch_types = 1;
-        }
-      }
-      elm_size = subtype->size;
+  case DW_TAG_array_type:
+    subtype = type->subtype;
+    switch (subtype->type) {
+    case DW_TAG_unspecified_type:
+      return 1;
+
+    case DW_TAG_base_type:
+    case DW_TAG_enumeration_type:
+    case DW_TAG_pointer_type:
+    case DW_TAG_reference_type:
+    case DW_TAG_rvalue_reference_type:
+    case DW_TAG_structure_type:
+    case DW_TAG_class_type:
+    case DW_TAG_union_type:
+      if (subtype->full_type)
+        subtype = subtype->full_type;
+      elm_size = subtype->byte_size;
       break;
-    case e_dw_typedef:
-    case e_dw_volatile_type:
-      subsubtype = xbt_dict_get_or_null(types, subtype->dw_type_id);
-      if(subsubtype->size == 0){ /*declaration of the type, need the complete description */
-        subsubtype = xbt_dict_get_or_null(types, get_type_description(types, subsubtype->name));
-        if(subsubtype == NULL){
-          subsubtype = xbt_dict_get_or_null(other_types, get_type_description(other_types, subsubtype->name));
-          switch_types = 1;
-        }
-      }
-      elm_size = subsubtype->size;
+    case DW_TAG_const_type:
+    case DW_TAG_typedef:
+    case DW_TAG_volatile_type:
+      subsubtype = subtype->subtype;
+      if (subsubtype->full_type)
+        subsubtype = subsubtype->full_type;
+      elm_size = subsubtype->byte_size;
       break;
-    default : 
+    default:
       return 0;
       break;
     }
-    for(i=0; i<type->size; i++){
-      if(switch_types)
-        res = compare_areas_with_type((char *)area1 + (i*elm_size), (char *)area2 + (i*elm_size), other_types, types, type->dw_type_id, region_size, region_type, start_data, pointer_level);
-      else
-        res = compare_areas_with_type((char *)area1 + (i*elm_size), (char *)area2 + (i*elm_size), types, other_types, type->dw_type_id, region_size, region_type, start_data, pointer_level);
-      if(res != 0)
+    for (i = 0; i < type->element_count; i++) {
+      res =
+          compare_areas_with_type((char *) area1 + (i * elm_size),
+                                  (char *) area2 + (i * elm_size), snapshot1,
+                                  snapshot2, type->subtype, region_size,
+                                  region_type, start_data, pointer_level);
+      if (res == 1)
         return res;
     }
     break;
-  case e_dw_pointer_type: 
-    if(type->dw_type_id && ((dw_type_t)xbt_dict_get_or_null(types, type->dw_type_id))->type == e_dw_subroutine_type){
-      addr_pointed1 = *((void **)(area1)); 
-      addr_pointed2 = *((void **)(area2));
+  case DW_TAG_pointer_type:
+  case DW_TAG_reference_type:
+  case DW_TAG_rvalue_reference_type:
+
+    addr_pointed1 = *((void **) (area1));
+    addr_pointed2 = *((void **) (area2));
+
+    if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
       return (addr_pointed1 != addr_pointed2);
-    }else{
-      addr_pointed1 = *((void **)(area1)); 
-      addr_pointed2 = *((void **)(area2));
-      
-      if((addr_pointed1 == addr_pointed2) && ((pointed_area_size1 = get_pointed_area_size(addr_pointed1, 1)) != (pointed_area_size2 = get_pointed_area_size(addr_pointed2, 2))))
-        return -1;
-      if(addr_pointed1 == NULL && addr_pointed2 == NULL)
+    } else {
+
+      if (addr_pointed1 == NULL && addr_pointed2 == NULL)
         return 0;
-      if(already_compared_pointers(addr_pointed1, addr_pointed2) != -1)
+      if (!add_compared_pointers(addr_pointed1, addr_pointed2))
         return 0;
-      add_compared_pointers(addr_pointed1, addr_pointed2);
 
       pointer_level++;
-      
-      if(addr_pointed1 > std_heap && (char *)addr_pointed1 < (char*) std_heap + STD_HEAP_SIZE && addr_pointed2 > std_heap && (char *)addr_pointed2 < (char*) std_heap + STD_HEAP_SIZE){
-        return compare_heap_area(addr_pointed1, addr_pointed2, NULL, types, other_types, type->dw_type_id, pointer_level); 
-      }else if(addr_pointed1 > start_data && (char*)addr_pointed1 <= (char *)start_data + region_size && addr_pointed2 > start_data && (char*)addr_pointed2 <= (char *)start_data + region_size){
-        if(type->dw_type_id == NULL)
-          return  (addr_pointed1 != addr_pointed2);
-        else
-          return compare_areas_with_type(addr_pointed1, addr_pointed2, types, other_types, type->dw_type_id, region_size, region_type, start_data, pointer_level); 
-      }else{
-        return  (addr_pointed1 != addr_pointed2);
+
+      // Some cases are not handled here:
+      // * the pointers lead to different areas (one to the heap, the other to the RW segment ...);
+      // * a pointer leads to the read-only segment of the current object;
+      // * a pointer lead to a different ELF object.
+
+      if (addr_pointed1 > std_heap
+          && addr_pointed1 < mc_snapshot_get_heap_end(snapshot1)) {
+        if (!
+            (addr_pointed2 > std_heap
+             && addr_pointed2 < mc_snapshot_get_heap_end(snapshot2)))
+          return 1;
+        // The pointers are both in the heap:
+        return compare_heap_area(addr_pointed1, addr_pointed2, snapshot1,
+                                 snapshot2, NULL, type->subtype, pointer_level);
+      }
+      // The pointers are both in the current object R/W segment:
+      else if (addr_pointed1 > start_data
+               && (char *) addr_pointed1 <= (char *) start_data + region_size) {
+        if (!
+            (addr_pointed2 > start_data
+             && (char *) addr_pointed2 <= (char *) start_data + region_size))
+          return 1;
+        if (type->dw_type_id == NULL)
+          return (addr_pointed1 != addr_pointed2);
+        else {
+          void *translated_addr_pointer1 =
+              mc_translate_address((uintptr_t) addr_pointed1, snapshot1);
+          void *translated_addr_pointer2 =
+              mc_translate_address((uintptr_t) addr_pointed2, snapshot2);
+          return compare_areas_with_type(translated_addr_pointer1,
+                                         translated_addr_pointer2, snapshot1,
+                                         snapshot2, type->subtype, region_size,
+                                         region_type, start_data,
+                                         pointer_level);
+        }
+      }
+
+      else {
+        return (addr_pointed1 != addr_pointed2);
       }
     }
     break;
-  case e_dw_structure_type:
-    xbt_dynar_foreach(type->members, cursor, member){
-      res = compare_areas_with_type((char *)area1 + member->offset, (char *)area2 + member->offset, types, other_types, member->dw_type_id, region_size, region_type, start_data, pointer_level);
-      if(res == 1)
+  case DW_TAG_structure_type:
+  case DW_TAG_class_type:
+    xbt_dynar_foreach(type->members, cursor, member) {
+      void *member1 =
+          mc_member_snapshot_resolve(area1, type, member, snapshot1);
+      void *member2 =
+          mc_member_snapshot_resolve(area2, type, member, snapshot2);
+      res =
+          compare_areas_with_type(member1, member2, snapshot1, snapshot2,
+                                  member->subtype, region_size, region_type,
+                                  start_data, pointer_level);
+      if (res == 1)
         return res;
     }
     break;
-  case e_dw_subroutine_type:
+  case DW_TAG_subroutine_type:
     return -1;
     break;
   default:
     XBT_VERB("Unknown case : %d", type->type);
     break;
   }
-  
+
   return 0;
 }
 
-static int compare_global_variables(int region_type, mc_mem_region_t r1, mc_mem_region_t r2){
+static int compare_global_variables(int region_type, mc_mem_region_t r1,
+                                    mc_mem_region_t r2, mc_snapshot_t snapshot1,
+                                    mc_snapshot_t snapshot2)
+{
 
-  if(!compared_pointers){
-    compared_pointers = xbt_dynar_new(sizeof(pointers_pair_t), pointers_pair_free_voidp);
-    MC_ignore_global_variable("compared_pointers");
-  }else{
+  if (!compared_pointers) {
+    compared_pointers =
+        xbt_dynar_new(sizeof(pointers_pair_t), pointers_pair_free_voidp);
+  } else {
     xbt_dynar_reset(compared_pointers);
   }
 
   xbt_dynar_t variables;
-  xbt_dict_t types, other_types;
   int res;
   unsigned int cursor = 0;
   dw_variable_t current_var;
   size_t offset;
   void *start_data;
+  void *start_data_binary = mc_binary_info->start_rw;
+  void *start_data_libsimgrid = mc_libsimgrid_info->start_rw;
 
-  if(region_type == 2){
-    variables = mc_global_variables_binary;
-    types = mc_variables_type_binary;
-    other_types = mc_variables_type_libsimgrid;
+  mc_object_info_t object_info = NULL;
+  if (region_type == 2) {
+    object_info = mc_binary_info;
     start_data = start_data_binary;
-  }else{
-    variables = mc_global_variables_libsimgrid;
-    types = mc_variables_type_libsimgrid;
-    other_types = mc_variables_type_binary;
+  } else {
+    object_info = mc_libsimgrid_info;
     start_data = start_data_libsimgrid;
   }
-
-  xbt_dynar_foreach(variables, cursor, current_var){
-
-    if(region_type == 2)
-      offset = (char *)current_var->address.address - (char *)start_data_binary;
-    else
-      offset = (char *)current_var->address.address - (char *)start_data_libsimgrid;
-
-    res = compare_areas_with_type((char *)r1->data + offset, (char *)r2->data + offset, types, other_types, current_var->type_origin, r1->size, region_type, start_data, 0);
-    if(res == 1){
-      XBT_VERB("Global variable %s is different between snapshots", current_var->name);
+  variables = object_info->global_variables;
+
+  xbt_dynar_foreach(variables, cursor, current_var) {
+
+    // If the variable is not in this object, skip it:
+    // We do not expect to find a pointer to something which is not reachable
+    // by the global variables.
+    if ((char *) current_var->address < (char *) object_info->start_rw
+        || (char *) current_var->address > (char *) object_info->end_rw)
+      continue;
+
+    offset = (char *) current_var->address - (char *) object_info->start_rw;
+
+    dw_type_t bvariable_type = current_var->type;
+    res =
+        compare_areas_with_type((char *) r1->data + offset,
+                                (char *) r2->data + offset, snapshot1,
+                                snapshot2, bvariable_type, r1->size,
+                                region_type, start_data, 0);
+    if (res == 1) {
+      XBT_VERB("Global variable %s (%p - %p) is different between snapshots",
+               current_var->name, (char *) r1->data + offset,
+               (char *) r2->data + offset);
       xbt_dynar_free(&compared_pointers);
       compared_pointers = NULL;
       return 1;
@@ -287,39 +326,76 @@ static int compare_global_variables(int region_type, mc_mem_region_t r1, mc_mem_
 
 }
 
-static int compare_local_variables(mc_snapshot_stack_t stack1, mc_snapshot_stack_t stack2, void *heap1, void *heap2){
-
-  if(!compared_pointers){
-    compared_pointers = xbt_dynar_new(sizeof(pointers_pair_t), pointers_pair_free_voidp);
-    MC_ignore_global_variable("compared_pointers");
-  }else{
+static int compare_local_variables(mc_snapshot_t snapshot1,
+                                   mc_snapshot_t snapshot2,
+                                   mc_snapshot_stack_t stack1,
+                                   mc_snapshot_stack_t stack2, void *heap1,
+                                   void *heap2)
+{
+  void *start_data_binary = mc_binary_info->start_rw;
+  void *start_data_libsimgrid = mc_libsimgrid_info->start_rw;
+
+  if (!compared_pointers) {
+    compared_pointers =
+        xbt_dynar_new(sizeof(pointers_pair_t), pointers_pair_free_voidp);
+  } else {
     xbt_dynar_reset(compared_pointers);
   }
 
-  if(xbt_dynar_length(stack1->local_variables) != xbt_dynar_length(stack2->local_variables)){
+  if (xbt_dynar_length(stack1->local_variables) !=
+      xbt_dynar_length(stack2->local_variables)) {
     XBT_VERB("Different number of local variables");
     xbt_dynar_free(&compared_pointers);
     compared_pointers = NULL;
     return 1;
-  }else{
+  } else {
     unsigned int cursor = 0;
     local_variable_t current_var1, current_var2;
     int offset1, offset2, res;
-    while(cursor < xbt_dynar_length(stack1->local_variables)){
-      current_var1 = (local_variable_t)xbt_dynar_get_as(stack1->local_variables, cursor, local_variable_t);
-      current_var2 = (local_variable_t)xbt_dynar_get_as(stack2->local_variables, cursor, local_variable_t);
-      if(strcmp(current_var1->name, current_var2->name) != 0 || strcmp(current_var1->frame, current_var2->frame) != 0 || current_var1->ip != current_var2->ip){
+    while (cursor < xbt_dynar_length(stack1->local_variables)) {
+      current_var1 =
+          (local_variable_t) xbt_dynar_get_as(stack1->local_variables, cursor,
+                                              local_variable_t);
+      current_var2 =
+          (local_variable_t) xbt_dynar_get_as(stack2->local_variables, cursor,
+                                              local_variable_t);
+      if (strcmp(current_var1->name, current_var2->name) != 0
+          || current_var1->subprogram != current_var1->subprogram
+          || current_var1->ip != current_var2->ip) {
         xbt_dynar_free(&compared_pointers);
+        // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+        XBT_VERB
+            ("Different name of variable (%s - %s) or frame (%s - %s) or ip (%lu - %lu)",
+             current_var1->name, current_var2->name,
+             current_var1->subprogram->name, current_var2->subprogram->name,
+             current_var1->ip, current_var2->ip);
         return 1;
       }
-      offset1 = (char *)current_var1->address - (char *)std_heap;
-      offset2 = (char *)current_var2->address - (char *)std_heap;
-      if(current_var1->region == 1)
-        res = compare_areas_with_type( (char *)heap1 + offset1, (char *)heap2 + offset2, mc_variables_type_libsimgrid, mc_variables_type_binary, current_var1->type, 0, 1, start_data_libsimgrid, 0l);
-      else
-        res = compare_areas_with_type( (char *)heap1 + offset1, (char *)heap2 + offset2, mc_variables_type_binary, mc_variables_type_libsimgrid, current_var1->type, 0, 2, start_data_binary, 0l);
-      if(res == 1){
-        XBT_VERB("Local variable %s in frame %s  is different between snapshots", current_var1->name, current_var1->frame);
+      offset1 = (char *) current_var1->address - (char *) std_heap;
+      offset2 = (char *) current_var2->address - (char *) std_heap;
+      // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+
+      if (current_var1->region == 1) {
+        dw_type_t subtype = current_var1->type;
+        res =
+            compare_areas_with_type((char *) heap1 + offset1,
+                                    (char *) heap2 + offset2, snapshot1,
+                                    snapshot2, subtype, 0, 1,
+                                    start_data_libsimgrid, 0);
+      } else {
+        dw_type_t subtype = current_var2->type;
+        res =
+            compare_areas_with_type((char *) heap1 + offset1,
+                                    (char *) heap2 + offset2, snapshot1,
+                                    snapshot2, subtype, 0, 2, start_data_binary,
+                                    0);
+      }
+      if (res == 1) {
+        // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+        XBT_VERB
+            ("Local variable %s (%p - %p) in frame %s  is different between snapshots",
+             current_var1->name, (char *) heap1 + offset1,
+             (char *) heap2 + offset2, current_var1->subprogram->name);
         xbt_dynar_free(&compared_pointers);
         compared_pointers = NULL;
         return res;
@@ -332,10 +408,28 @@ static int compare_local_variables(mc_snapshot_stack_t stack1, mc_snapshot_stack
   }
 }
 
-int snapshot_compare(void *p1, void *p2){
-
-  mc_snapshot_t s1 = ((mc_pair_t)p1)->graph_state->system_state;
-  mc_snapshot_t s2 = ((mc_pair_t)p2)->graph_state->system_state;
+int snapshot_compare(void *state1, void *state2)
+{
+
+  mc_snapshot_t s1, s2;
+  int num1, num2;
+
+  if (_sg_mc_property_file && _sg_mc_property_file[0] != '\0') {        /* Liveness MC */
+    s1 = ((mc_visited_pair_t) state1)->graph_state->system_state;
+    s2 = ((mc_visited_pair_t) state2)->graph_state->system_state;
+    num1 = ((mc_visited_pair_t) state1)->num;
+    num2 = ((mc_visited_pair_t) state2)->num;
+    /* Firstly compare automaton state */
+    /*if(xbt_automaton_state_compare(((mc_pair_t)state1)->automaton_state, ((mc_pair_t)state2)->automaton_state) != 0)
+       return 1;
+       if(xbt_automaton_propositional_symbols_compare_value(((mc_pair_t)state1)->atomic_propositions, ((mc_pair_t)state2)->atomic_propositions) != 0)
+       return 1; */
+  } else {                      /* Safety MC */
+    s1 = ((mc_visited_state_t) state1)->system_state;
+    s2 = ((mc_visited_state_t) state2)->system_state;
+    num1 = ((mc_visited_state_t) state1)->num;
+    num2 = ((mc_visited_state_t) state2)->num;
+  }
 
   int errors = 0;
   int res_init;
@@ -345,30 +439,56 @@ int snapshot_compare(void *p1, void *p2){
 
   xbt_os_walltimer_start(global_timer);
 
-  #ifdef MC_DEBUG
-    xbt_os_walltimer_start(timer);
-  #endif
+#ifdef MC_DEBUG
+  xbt_os_walltimer_start(timer);
+#endif
+
+  int hash_result = 0;
+  if (_sg_mc_hash) {
+    hash_result = (s1->hash != s2->hash);
+    if (hash_result) {
+      XBT_VERB("(%d - %d) Different hash : 0x%" PRIx64 "--0x%" PRIx64, num1,
+               num2, s1->hash, s2->hash);
+#ifndef MC_DEBUG
+      return 1;
+#endif
+    } else {
+      XBT_VERB("(%d - %d) Same hash : 0x%" PRIx64, num1, num2, s1->hash);
+    }
+  }
+
+  /* Compare enabled processes */
+  unsigned int cursor;
+  int pid;
+  xbt_dynar_foreach(s1->enabled_processes, cursor, pid){
+    if(!xbt_dynar_member(s2->enabled_processes, &pid))
+      XBT_VERB("(%d - %d) Different enabled processes", num1, num2);
+  }
 
-  /* Compare size of stacks */
   int i = 0;
   size_t size_used1, size_used2;
   int is_diff = 0;
-  while(i < xbt_dynar_length(s1->stacks)){
+
+  /* Compare size of stacks */
+  while (i < xbt_dynar_length(s1->stacks)) {
     size_used1 = s1->stack_sizes[i];
     size_used2 = s2->stack_sizes[i];
-    if(size_used1 != size_used2){
-    #ifdef MC_DEBUG
-      if(is_diff == 0){
+    if (size_used1 != size_used2) {
+#ifdef MC_DEBUG
+      if (is_diff == 0) {
         xbt_os_walltimer_stop(timer);
-        mc_comp_times->stacks_sizes_comparison_time = xbt_os_timer_elapsed(timer);
+        mc_comp_times->stacks_sizes_comparison_time =
+            xbt_os_timer_elapsed(timer);
       }
-      XBT_DEBUG("(%d - %d) Different size used in stacks : %zu - %zu", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num, size_used1, size_used2);
+      XBT_DEBUG("(%d - %d) Different size used in stacks : %zu - %zu", num1,
+                num2, size_used1, size_used2);
       errors++;
       is_diff = 1;
-    #else
-      #ifdef MC_VERBOSE
-      XBT_VERB("(%d - %d) Different size used in stacks : %zu - %zu", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num, size_used1, size_used2);
-      #endif
+#else
+#ifdef MC_VERBOSE
+      XBT_VERB("(%d - %d) Different size used in stacks : %zu - %zu", num1,
+               num2, size_used1, size_used2);
+#endif
 
       xbt_os_walltimer_stop(timer);
       xbt_os_timer_free(timer);
@@ -377,152 +497,76 @@ int snapshot_compare(void *p1, void *p2){
       xbt_os_timer_free(global_timer);
 
       return 1;
-    #endif  
+#endif
     }
     i++;
   }
 
-  #ifdef MC_DEBUG
-    if(is_diff == 0)
-      xbt_os_walltimer_stop(timer);
-    xbt_os_walltimer_start(timer);
-  #endif
-
-  /* Compare hash of global variables */
-  if(s1->hash_global != NULL && s2->hash_global != NULL){
-    if(strcmp(s1->hash_global, s2->hash_global) != 0){
-      #ifdef MC_DEBUG
-        xbt_os_walltimer_stop(timer);
-        mc_comp_times->hash_global_variables_comparison_time = xbt_os_timer_elapsed(timer);
-        XBT_DEBUG("Different hash of global variables : %s - %s", s1->hash_global, s2->hash_global); 
-        errors++; 
-      #else
-        #ifdef MC_VERBOSE
-          XBT_VERB("Different hash of global variables : %s - %s", s1->hash_global, s2->hash_global); 
-        #endif
-
-        xbt_os_walltimer_stop(timer);
-        xbt_os_timer_free(timer);
-        xbt_os_walltimer_stop(global_timer);
-        mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
-        xbt_os_timer_free(global_timer);
-
-        return 1;
-      #endif
-    }
-  }
-
-  #ifdef MC_DEBUG
-    xbt_os_walltimer_start(timer);
-  #endif
-
-  /* Compare hash of local variables */
-  if(s1->hash_local != NULL && s2->hash_local != NULL){
-    if(strcmp(s1->hash_local, s2->hash_local) != 0){
-      #ifdef MC_DEBUG
-        xbt_os_walltimer_stop(timer);
-        mc_comp_times->hash_local_variables_comparison_time = xbt_os_timer_elapsed(timer);
-        XBT_DEBUG("Different hash of local variables : %s - %s", s1->hash_local, s2->hash_local); 
-        errors++; 
-      #else
-        #ifdef MC_VERBOSE
-          XBT_VERB("Different hash of local variables : %s - %s", s1->hash_local, s2->hash_local); 
-        #endif
-
-        xbt_os_walltimer_stop(timer);
-        xbt_os_timer_free(timer);
-        xbt_os_walltimer_stop(global_timer);
-        mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
-        xbt_os_timer_free(global_timer);
-
-        return 1;
-      #endif
-    }
-  }
-
-  #ifdef MC_DEBUG
-    xbt_os_walltimer_start(timer);
-  #endif
+#ifdef MC_DEBUG
+  if (is_diff == 0)
+    xbt_os_walltimer_stop(timer);
+  xbt_os_walltimer_start(timer);
+#endif
 
   /* Init heap information used in heap comparison algorithm */
-  res_init = init_heap_information((xbt_mheap_t)s1->regions[0]->data, (xbt_mheap_t)s2->regions[0]->data, s1->to_ignore, s2->to_ignore);
-  if(res_init == -1){
-     #ifdef MC_DEBUG
-    XBT_DEBUG("(%d - %d) Different heap information", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num); 
-        errors++; 
-      #else
-        #ifdef MC_VERBOSE
-        XBT_VERB("(%d - %d) Different heap information", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num); 
-        #endif
-
-        xbt_os_walltimer_stop(global_timer);
-        mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
-        xbt_os_timer_free(global_timer);
+  res_init =
+      init_heap_information((xbt_mheap_t) s1->regions[0]->data,
+                            (xbt_mheap_t) s2->regions[0]->data, s1->to_ignore,
+                            s2->to_ignore);
+  if (res_init == -1) {
+#ifdef MC_DEBUG
+    XBT_DEBUG("(%d - %d) Different heap information", num1, num2);
+    errors++;
+#else
+#ifdef MC_VERBOSE
+    XBT_VERB("(%d - %d) Different heap information", num1, num2);
+#endif
 
-        return 1;
-      #endif
-  }
+    xbt_os_walltimer_stop(global_timer);
+    mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
+    xbt_os_timer_free(global_timer);
 
-  #ifdef MC_DEBUG
-    xbt_os_walltimer_start(timer);
-  #endif
+    return 1;
+#endif
+  }
+#ifdef MC_DEBUG
+  xbt_os_walltimer_start(timer);
+#endif
 
   /* Stacks comparison */
-  unsigned int  cursor = 0;
+  cursor = 0;
   int diff_local = 0;
+#ifdef MC_DEBUG
   is_diff = 0;
+#endif
   mc_snapshot_stack_t stack1, stack2;
-    
-  while(cursor < xbt_dynar_length(s1->stacks)){
-    stack1 = (mc_snapshot_stack_t)xbt_dynar_get_as(s1->stacks, cursor, mc_snapshot_stack_t);
-    stack2 = (mc_snapshot_stack_t)xbt_dynar_get_as(s2->stacks, cursor, mc_snapshot_stack_t);
-    diff_local = compare_local_variables(stack1, stack2, s1->regions[0]->data, s2->regions[0]->data);
-    if(diff_local > 0){
-      #ifdef MC_DEBUG
-        if(is_diff == 0){
-          xbt_os_walltimer_stop(timer);
-          mc_comp_times->stacks_comparison_time = xbt_os_timer_elapsed(timer);
-        }
-        XBT_DEBUG("(%d - %d) Different local variables between stacks %d", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num, cursor + 1);
-        errors++;
-        is_diff = 1;
-      #else
-        
-        #ifdef MC_VERBOSE
-        XBT_VERB("(%d - %d) Different local variables between stacks %d", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num, cursor + 1);
-        #endif
-          
-        reset_heap_information();
-        xbt_os_walltimer_stop(timer);
-        xbt_os_timer_free(timer);
-        xbt_os_walltimer_stop(global_timer);
-        mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
-        xbt_os_timer_free(global_timer);
- 
-        return 1;
-      #endif
-    }
-    cursor++;
-  }
 
-  #ifdef MC_DEBUG
-    if(is_diff == 0)
-      xbt_os_walltimer_stop(timer);
-    xbt_os_walltimer_start(timer);
-  #endif
-
-  /* Compare binary global variables */
-  is_diff = compare_global_variables(2, s1->regions[2], s2->regions[2]);
-  if(is_diff != 0){
-    #ifdef MC_DEBUG
-      xbt_os_walltimer_stop(timer);
-      mc_comp_times->binary_global_variables_comparison_time = xbt_os_timer_elapsed(timer);
-      XBT_DEBUG("(%d - %d) Different global variables in binary", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num);
+  while (cursor < xbt_dynar_length(s1->stacks)) {
+    stack1 =
+        (mc_snapshot_stack_t) xbt_dynar_get_as(s1->stacks, cursor,
+                                               mc_snapshot_stack_t);
+    stack2 =
+        (mc_snapshot_stack_t) xbt_dynar_get_as(s2->stacks, cursor,
+                                               mc_snapshot_stack_t);
+    diff_local =
+        compare_local_variables(s1, s2, stack1, stack2, s1->regions[0]->data,
+                                s2->regions[0]->data);
+    if (diff_local > 0) {
+#ifdef MC_DEBUG
+      if (is_diff == 0) {
+        xbt_os_walltimer_stop(timer);
+        mc_comp_times->stacks_comparison_time = xbt_os_timer_elapsed(timer);
+      }
+      XBT_DEBUG("(%d - %d) Different local variables between stacks %d", num1,
+                num2, cursor + 1);
       errors++;
-    #else
-      #ifdef MC_VERBOSE
-      XBT_VERB("(%d - %d) Different global variables in binary", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num);
-      #endif
+      is_diff = 1;
+#else
+
+#ifdef MC_VERBOSE
+      XBT_VERB("(%d - %d) Different local variables between stacks %d", num1,
+               num2, cursor + 1);
+#endif
 
       reset_heap_information();
       xbt_os_walltimer_stop(timer);
@@ -532,28 +576,46 @@ int snapshot_compare(void *p1, void *p2){
       xbt_os_timer_free(global_timer);
 
       return 1;
-    #endif
+#endif
+    }
+    cursor++;
   }
 
-  #ifdef MC_DEBUG
-    if(is_diff == 0)
+
+
+  const char *names[3] = { "?", "libsimgrid", "binary" };
+#ifdef MC_DEBUG
+  double *times[3] = {
+    NULL,
+    &mc_comp_times->libsimgrid_global_variables_comparison_time,
+    &mc_comp_times->binary_global_variables_comparison_time
+  };
+#endif
+
+  int k = 0;
+  for (k = 2; k != 0; --k) {
+#ifdef MC_DEBUG
+    if (is_diff == 0)
       xbt_os_walltimer_stop(timer);
     xbt_os_walltimer_start(timer);
-  #endif
+#endif
 
-  /* Compare libsimgrid global variables */
-  is_diff = compare_global_variables(1, s1->regions[1], s2->regions[1]);
-  if(is_diff != 0){
-    #ifdef MC_DEBUG
+    /* Compare global variables */
+    is_diff =
+        compare_global_variables(k, s1->regions[k], s2->regions[k], s1, s2);
+    if (is_diff != 0) {
+#ifdef MC_DEBUG
       xbt_os_walltimer_stop(timer);
-      mc_comp_times->libsimgrid_global_variables_comparison_time = xbt_os_timer_elapsed(timer);
-      XBT_DEBUG("(%d - %d) Different global variables in libsimgrid", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num);
+      *times[k] = xbt_os_timer_elapsed(timer);
+      XBT_DEBUG("(%d - %d) Different global variables in %s", num1, num2,
+                names[k]);
       errors++;
-    #else
-      #ifdef MC_VERBOSE
-      XBT_VERB("(%d - %d) Different global variables in libsimgrid", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num);
-      #endif
-        
+#else
+#ifdef MC_VERBOSE
+      XBT_VERB("(%d - %d) Different global variables in %s", num1, num2,
+               names[k]);
+#endif
+
       reset_heap_information();
       xbt_os_walltimer_stop(timer);
       xbt_os_timer_free(timer);
@@ -562,72 +624,95 @@ int snapshot_compare(void *p1, void *p2){
       xbt_os_timer_free(global_timer);
 
       return 1;
-    #endif
+#endif
+    }
   }
 
-  #ifdef MC_DEBUG
-    xbt_os_walltimer_start(timer);
-  #endif
+#ifdef MC_DEBUG
+  xbt_os_walltimer_start(timer);
+#endif
 
   /* Compare heap */
-  if(mmalloc_compare_heap((xbt_mheap_t)s1->regions[0]->data, (xbt_mheap_t)s2->regions[0]->data) > 0){
-
-    #ifdef MC_DEBUG
-      xbt_os_walltimer_stop(timer);
-      mc_comp_times->heap_comparison_time = xbt_os_timer_elapsed(timer); 
-      XBT_DEBUG("(%d - %d) Different heap (mmalloc_compare)", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num);
-      errors++;
-    #else
- 
-      #ifdef MC_VERBOSE
-      XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", ((mc_pair_t)p1)->num, ((mc_pair_t)p2)->num);
-      #endif
-       
-      reset_heap_information();
-      xbt_os_walltimer_stop(timer);
-      xbt_os_timer_free(timer);
-      xbt_os_walltimer_stop(global_timer);
-      mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
-      xbt_os_timer_free(global_timer);
+  if (mmalloc_compare_heap(s1, s2, (xbt_mheap_t) s1->regions[0]->data,
+                           (xbt_mheap_t) s2->regions[0]->data) > 0) {
+
+#ifdef MC_DEBUG
+    xbt_os_walltimer_stop(timer);
+    mc_comp_times->heap_comparison_time = xbt_os_timer_elapsed(timer);
+    XBT_DEBUG("(%d - %d) Different heap (mmalloc_compare)", num1, num2);
+    errors++;
+#else
+
+#ifdef MC_VERBOSE
+    XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", num1, num2);
+#endif
+
+    reset_heap_information();
+    xbt_os_walltimer_stop(timer);
+    xbt_os_timer_free(timer);
+    xbt_os_walltimer_stop(global_timer);
+    mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
+    xbt_os_timer_free(global_timer);
 
-      return 1;
-    #endif
-  }else{
-    #ifdef MC_DEBUG
-      xbt_os_walltimer_stop(timer);
-    #endif
+    return 1;
+#endif
+  } else {
+#ifdef MC_DEBUG
+    xbt_os_walltimer_stop(timer);
+#endif
   }
 
   reset_heap_information();
-  
+
   xbt_os_walltimer_stop(timer);
   xbt_os_timer_free(timer);
 
-  #ifdef MC_VERBOSE
-    xbt_os_walltimer_stop(global_timer);
-    mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
-  #endif
+#ifdef MC_VERBOSE
+  xbt_os_walltimer_stop(global_timer);
+  mc_snapshot_comparison_time = xbt_os_timer_elapsed(global_timer);
+#endif
 
   xbt_os_timer_free(global_timer);
 
-  #ifdef MC_DEBUG
-    print_comparison_times();
-  #endif
+#ifdef MC_DEBUG
+  print_comparison_times();
+#endif
+
+#ifdef MC_VERBOSE
+  if (errors || hash_result)
+    XBT_VERB("(%d - %d) Difference found", num1, num2);
+  else
+    XBT_VERB("(%d - %d) No difference found", num1, num2);
+#endif
+
+#if defined(MC_DEBUG) && defined(MC_VERBOSE)
+  if (_sg_mc_hash) {
+    // * false positive SHOULD be avoided.
+    // * There MUST not be any false negative.
+
+    XBT_VERB("(%d - %d) State equality hash test is %s %s", num1, num2,
+             (hash_result != 0) == (errors != 0) ? "true" : "false",
+             !hash_result ? "positive" : "negative");
+  }
+#endif
+
+  return errors > 0 || hash_result;
 
-  return errors > 0;
-  
 }
 
 /***************************** Statistics *****************************/
 /*******************************************************************/
 
-void print_comparison_times(){
+void print_comparison_times()
+{
   XBT_DEBUG("*** Comparison times ***");
   XBT_DEBUG("- Nb processes : %f", mc_comp_times->nb_processes_comparison_time);
   XBT_DEBUG("- Nb bytes used : %f", mc_comp_times->bytes_used_comparison_time);
   XBT_DEBUG("- Stacks sizes : %f", mc_comp_times->stacks_sizes_comparison_time);
-  XBT_DEBUG("- Binary global variables : %f", mc_comp_times->binary_global_variables_comparison_time);
-  XBT_DEBUG("- Libsimgrid global variables : %f", mc_comp_times->libsimgrid_global_variables_comparison_time);
+  XBT_DEBUG("- Binary global variables : %f",
+            mc_comp_times->binary_global_variables_comparison_time);
+  XBT_DEBUG("- Libsimgrid global variables : %f",
+            mc_comp_times->libsimgrid_global_variables_comparison_time);
   XBT_DEBUG("- Heap : %f", mc_comp_times->heap_comparison_time);
   XBT_DEBUG("- Stacks : %f", mc_comp_times->stacks_comparison_time);
 }
@@ -636,13 +721,14 @@ void print_comparison_times(){
 /***********************************************************************************/
 
 int SIMIX_pre_mc_compare_snapshots(smx_simcall_t simcall,
-                                   mc_snapshot_t s1, mc_snapshot_t s2){
+                                   mc_snapshot_t s1, mc_snapshot_t s2)
+{
   return snapshot_compare(s1, s2);
 }
 
-int MC_compare_snapshots(void *s1, void *s2){
-  
-  MC_ignore_local_variable("self", "simcall_BODY_mc_snapshot");
+int MC_compare_snapshots(void *s1, void *s2)
+{
+
   return simcall_mc_compare_snapshots(s1, s2);
 
 }