X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/033c672aea354365adbb5e82ab2ae9137be04984..be6ecad742f6daa971c70b04ddb4db64bad52f58:/src/surf/maxmin.cpp

diff --git a/src/surf/maxmin.cpp b/src/surf/maxmin.cpp
index 0fafd622f9..e5006daa3d 100644
--- a/src/surf/maxmin.cpp
+++ b/src/surf/maxmin.cpp
@@ -6,22 +6,20 @@
 /* \file callbacks.h */
 
 #include "maxmin_private.hpp"
+#include "xbt/backtrace.hpp"
 #include "xbt/log.h"
 #include "xbt/mallocator.h"
 #include "xbt/sysdep.h"
+#include <algorithm>
+#include <cmath>
+#include <cstdlib>
 #include <cxxabi.h>
 #include <limits>
-#include <math.h>
-#include <stdlib.h>
+#include <vector>
 
 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(surf_maxmin, surf, "Logging specific to SURF (maxmin)");
 
-typedef struct s_dyn_light {
-  int *data;
-  int pos;
-  int size;
-} s_dyn_light_t;
-typedef s_dyn_light_t* dyn_light_t;
+typedef std::vector<int> dyn_light_t;
 
 double sg_maxmin_precision = 0.00001; /* Change this with --cfg=maxmin/precision:VALUE */
 double sg_surf_precision   = 0.00001; /* Change this with --cfg=surf/precision:VALUE */
@@ -44,7 +42,8 @@ static void lmm_disable_var(lmm_system_t sys, lmm_variable_t var);
 static int lmm_concurrency_slack(lmm_constraint_t cnstr);
 static int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var);
 
-inline int lmm_element_concurrency(lmm_element_t elem) {
+static inline int lmm_element_concurrency(lmm_element_t elem)
+{
   //Ignore element with weight less than one (e.g. cross-traffic)
   return (elem->consumption_weight >= 1) ? 1 : 0;
   //There are other alternatives, but they will change the behaviour of the model..
@@ -55,12 +54,14 @@ inline int lmm_element_concurrency(lmm_element_t elem) {
   //return (int)ceil(elem->weight);//Include element as the rounded-up integer value of the element weight
 }
 
-inline void lmm_decrease_concurrency(lmm_element_t elem) {
+static inline void lmm_decrease_concurrency(lmm_element_t elem)
+{
   xbt_assert(elem->constraint->concurrency_current>=lmm_element_concurrency(elem));
   elem->constraint->concurrency_current-=lmm_element_concurrency(elem);
 }
 
-inline void lmm_increase_concurrency(lmm_element_t elem) {
+static inline void lmm_increase_concurrency(lmm_element_t elem)
+{
   elem->constraint->concurrency_current+= lmm_element_concurrency(elem);
 
   lmm_constraint_t cnstr=elem->constraint;
@@ -110,7 +111,7 @@ static void lmm_check_concurrency(lmm_system_t sys)
   {
     lmm_variable_t var = (lmm_variable_t)varIt;
 
-    if (not var->cnsts_number)
+    if (var->cnsts.empty())
       continue;
 
     lmm_element_t elem     = &var->cnsts[0];
@@ -118,62 +119,47 @@ static void lmm_check_concurrency(lmm_system_t sys)
     int belong_to_disabled = xbt_swag_belongs(elem, &(elem->constraint->disabled_element_set));
     int belong_to_active   = xbt_swag_belongs(elem, &(elem->constraint->active_element_set));
 
-    for (int i = 1; i < var->cnsts_number; i++) {
-      elem = &var->cnsts[i];
-      xbt_assert(belong_to_enabled == xbt_swag_belongs(elem, &(elem->constraint->enabled_element_set)),
+    for (s_lmm_element_t const& elem : var->cnsts) {
+      xbt_assert(belong_to_enabled == xbt_swag_belongs(&elem, &(elem.constraint->enabled_element_set)),
                  "Variable inconsistency (1): enabled_element_set");
-      xbt_assert(belong_to_disabled == xbt_swag_belongs(elem, &(elem->constraint->disabled_element_set)),
+      xbt_assert(belong_to_disabled == xbt_swag_belongs(&elem, &(elem.constraint->disabled_element_set)),
                  "Variable inconsistency (2): disabled_element_set");
-      xbt_assert(belong_to_active == xbt_swag_belongs(elem, &(elem->constraint->active_element_set)),
+      xbt_assert(belong_to_active == xbt_swag_belongs(&elem, &(elem.constraint->active_element_set)),
                  "Variable inconsistency (3): active_element_set");
     }
   }
 }
 
-static inline void lmm_variable_remove(lmm_system_t sys, lmm_variable_t var)
+static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
 {
   XBT_IN("(sys=%p, var=%p)", sys, var);
   sys->modified = 1;
 
   // TODOLATER Can do better than that by leaving only the variable in only one enabled_element_set, call
   // lmm_update_modified_set, and then remove it..
-  if (var->cnsts_number)
+  if (not var->cnsts.empty())
     lmm_update_modified_set(sys, var->cnsts[0].constraint);
 
-  for (int i = 0; i < var->cnsts_number; i++) {
-    lmm_element_t elem = &var->cnsts[i];
+  for (s_lmm_element_t& elem : var->cnsts) {
     if (var->sharing_weight > 0)
-      lmm_decrease_concurrency(elem);
-    xbt_swag_remove(elem, &(elem->constraint->enabled_element_set));
-    xbt_swag_remove(elem, &(elem->constraint->disabled_element_set));
-    xbt_swag_remove(elem, &(elem->constraint->active_element_set));
-    int nelements = xbt_swag_size(&(elem->constraint->enabled_element_set)) +
-                    xbt_swag_size(&(elem->constraint->disabled_element_set));
+      lmm_decrease_concurrency(&elem);
+    xbt_swag_remove(&elem, &(elem.constraint->enabled_element_set));
+    xbt_swag_remove(&elem, &(elem.constraint->disabled_element_set));
+    xbt_swag_remove(&elem, &(elem.constraint->active_element_set));
+    int nelements = xbt_swag_size(&(elem.constraint->enabled_element_set)) +
+                    xbt_swag_size(&(elem.constraint->disabled_element_set));
     if (nelements == 0)
-      make_constraint_inactive(sys, elem->constraint);
+      make_constraint_inactive(sys, elem.constraint);
     else
-      lmm_on_disabled_var(sys, elem->constraint);
+      lmm_on_disabled_var(sys, elem.constraint);
   }
 
-  // Check if we can enable new variables going through the constraints where var was.
-  // Do it after removing all elements, so he first disabled variables get priority over those with smaller requirement
-  for (int i = 0; i < var->cnsts_number; i++) {
-    lmm_element_t elem = &var->cnsts[i];
-    if (xbt_swag_size(&(elem->constraint->disabled_element_set)))
-      lmm_on_disabled_var(sys, elem->constraint);
-  }
-
-  var->cnsts_number = 0;
+  var->cnsts.clear();
 
   lmm_check_concurrency(sys);
 
-  XBT_OUT();
-}
-
-static void lmm_var_free(lmm_system_t sys, lmm_variable_t var)
-{
-  lmm_variable_remove(sys, var);
   xbt_mallocator_release(sys->variable_mallocator, var);
+  XBT_OUT();
 }
 
 lmm_system_t lmm_system_new(bool selective_update)
@@ -181,7 +167,7 @@ lmm_system_t lmm_system_new(bool selective_update)
   s_lmm_variable_t var;
   s_lmm_constraint_t cnst;
 
-  lmm_system_t l = xbt_new0(s_lmm_system_t, 1);
+  lmm_system_t l = new s_lmm_system_t();
 
   l->modified = 0;
   l->selective_update_active = selective_update;
@@ -217,25 +203,22 @@ void lmm_system_free(lmm_system_t sys)
     return;
 
   while ((var = (lmm_variable_t) extract_variable(sys))) {
-    int status;
-    char* demangled = abi::__cxa_demangle(typeid(*var->id).name(), 0, 0, &status);
-
-    XBT_WARN("Probable bug: a %s variable (#%d) not removed before the LMM system destruction.", demangled,
+    auto demangled = simgrid::xbt::demangle(typeid(*var->id).name());
+    XBT_WARN("Probable bug: a %s variable (#%d) not removed before the LMM system destruction.", demangled.get(),
              var->id_int);
-    xbt_free(demangled);
     lmm_var_free(sys, var);
   }
   while ((cnst = (lmm_constraint_t) extract_constraint(sys)))
     lmm_cnst_free(sys, cnst);
 
   xbt_mallocator_free(sys->variable_mallocator);
-  free(sys);
+  delete sys;
 }
 
 static inline void lmm_cnst_free(lmm_system_t sys, lmm_constraint_t cnst)
 {
   make_constraint_inactive(sys, cnst);
-  free(cnst);
+  delete cnst;
 }
 
 lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id, double bound_value)
@@ -243,8 +226,8 @@ lmm_constraint_t lmm_constraint_new(lmm_system_t sys, void *id, double bound_val
   lmm_constraint_t cnst = nullptr;
   s_lmm_element_t elem;
 
-  cnst = xbt_new0(s_lmm_constraint_t, 1);
-  cnst->id = id;
+  cnst         = new s_lmm_constraint_t();
+  cnst->id     = id;
   cnst->id_int = Global_const_debug_id++;
   xbt_swag_init(&(cnst->enabled_element_set), xbt_swag_offset(elem, enabled_element_set_hookup));
   xbt_swag_init(&(cnst->disabled_element_set), xbt_swag_offset(elem, disabled_element_set_hookup));
@@ -297,32 +280,14 @@ int lmm_constraint_sharing_policy(lmm_constraint_t cnst)
   return (cnst->sharing_policy);
 }
 
-/* @brief Remove a constraint
- * Currently this is dead code, but it is exposed in maxmin.h
- * Apparently, this call was designed assuming that constraint would no more have elements in it.
- * If not the case, assertion will fail, and you need to add calls e.g. to lmm_shrink before effectively removing it.
- */
-inline void lmm_constraint_free(lmm_system_t sys,lmm_constraint_t cnst)
-{
-  xbt_assert(not xbt_swag_size(&(cnst->active_element_set)), "Removing constraint but it still has active elements");
-  xbt_assert(not xbt_swag_size(&(cnst->enabled_element_set)), "Removing constraint but it still has enabled elements");
-  xbt_assert(not xbt_swag_size(&(cnst->disabled_element_set)),
-             "Removing constraint but it still has disabled elements");
-  remove_constraint(sys, cnst);
-  lmm_cnst_free(sys, cnst);
-}
-
 static void *lmm_variable_mallocator_new_f()
 {
-  lmm_variable_t var = xbt_new(s_lmm_variable_t, 1);
-  var->cnsts = nullptr; /* will be created by realloc */
-  return var;
+  return new s_lmm_variable_t;
 }
 
 static void lmm_variable_mallocator_free_f(void *var)
 {
-  xbt_free(((lmm_variable_t) var)->cnsts);
-  xbt_free(var);
+  delete static_cast<lmm_variable_t>(var);
 }
 
 lmm_variable_t lmm_variable_new(lmm_system_t sys, simgrid::surf::Action* id, double sharing_weight, double bound,
@@ -333,20 +298,7 @@ lmm_variable_t lmm_variable_new(lmm_system_t sys, simgrid::surf::Action* id, dou
   lmm_variable_t var = (lmm_variable_t)xbt_mallocator_get(sys->variable_mallocator);
   var->id = id;
   var->id_int = Global_debug_id++;
-  var->cnsts = (s_lmm_element_t *) xbt_realloc(var->cnsts, number_of_constraints * sizeof(s_lmm_element_t));
-  for (int i = 0; i < number_of_constraints; i++) {
-    var->cnsts[i].enabled_element_set_hookup.next = nullptr;
-    var->cnsts[i].enabled_element_set_hookup.prev = nullptr;
-    var->cnsts[i].disabled_element_set_hookup.next = nullptr;
-    var->cnsts[i].disabled_element_set_hookup.prev = nullptr;
-    var->cnsts[i].active_element_set_hookup.next = nullptr;
-    var->cnsts[i].active_element_set_hookup.prev = nullptr;
-    var->cnsts[i].constraint = nullptr;
-    var->cnsts[i].variable = nullptr;
-    var->cnsts[i].consumption_weight               = 0.0;
-  }
-  var->cnsts_size = number_of_constraints;
-  var->cnsts_number = 0;
+  var->cnsts.reserve(number_of_constraints);
   var->sharing_weight    = sharing_weight;
   var->staged_weight = 0.0;
   var->bound = bound;
@@ -394,59 +346,6 @@ double lmm_variable_getbound(lmm_variable_t var)
   return (var->bound);
 }
 
-void lmm_shrink(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var)
-{
-  lmm_element_t elem = nullptr;
-  int found = 0;
-
-  for (int i = 0; i < var->cnsts_number; i++) {
-    elem = &(var->cnsts[i]);
-    if (elem->constraint == cnst) {
-      found = 1;
-      break;
-    }
-  }
-
-  if (not found) {
-    XBT_DEBUG("cnst %p is not found in var %p", cnst, var);
-    return;
-  }
-
-  sys->modified = 1;
-
-  XBT_DEBUG("remove elem(value %f, cnst %p, var %p) in var %p", elem->consumption_weight, elem->constraint,
-            elem->variable, var);
-
-  /* We are going to change the constraint object and the variable object.
-   * Propagate this change to other objects. Calling here before removing variable from not active elements
-   * (inactive elements are not visited)
-   */
-  lmm_update_modified_set(sys, cnst);
-  //Useful in case var was already removed from the constraint
-  lmm_update_modified_set(sys, var->cnsts[0].constraint); // will look up enabled_element_set of this constraint, and
-                                                     //then each var in the enabled_element_set, and each var->cnsts[i].
-
-  if(xbt_swag_remove(elem, &(elem->constraint->enabled_element_set)))
-    lmm_decrease_concurrency(elem);
-
-  xbt_swag_remove(elem, &(elem->constraint->active_element_set));
-  elem->constraint = nullptr;
-  elem->variable = nullptr;
-  elem->consumption_weight = 0;
-
-  var->cnsts_number -= 1;
-
-  //No variable in this constraint -> make it inactive
-  if (xbt_swag_size(&(cnst->enabled_element_set))+xbt_swag_size(&(cnst->disabled_element_set)) == 0)
-    make_constraint_inactive(sys, cnst);
-  else {
-    //Check maxconcurrency to see if we can enable new variables
-    lmm_on_disabled_var(sys,elem->constraint);
-  }
-
-  lmm_check_concurrency(sys);
-}
-
 void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, double consumption_weight)
 {
   sys->modified = 1;
@@ -455,10 +354,9 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, dou
   //If it does, substract it from the required slack
   int current_share = 0;
   if(var->concurrency_share>1){
-    for (int i = 0; i < var->cnsts_number; i++) {
-      if(var->cnsts[i].constraint==cnst &&
-         xbt_swag_belongs(&var->cnsts[i],&(var->cnsts[i].constraint->enabled_element_set)))
-         current_share+=lmm_element_concurrency(&(var->cnsts[i]));
+    for (s_lmm_element_t& elem : var->cnsts) {
+      if (elem.constraint == cnst && xbt_swag_belongs(&elem, &(elem.constraint->enabled_element_set)))
+        current_share += lmm_element_concurrency(&elem);
     }
   }
 
@@ -466,34 +364,35 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, dou
   if (var->sharing_weight > 0 && var->concurrency_share - current_share > lmm_concurrency_slack(cnst)) {
     double weight = var->sharing_weight;
     lmm_disable_var(sys,var);
-    for (int i = 0; i < var->cnsts_number; i++)
-      lmm_on_disabled_var(sys,var->cnsts[i].constraint);
+    for (s_lmm_element_t const& elem : var->cnsts)
+      lmm_on_disabled_var(sys, elem.constraint);
     consumption_weight = 0;
     var->staged_weight=weight;
     xbt_assert(not var->sharing_weight);
   }
 
-  xbt_assert(var->cnsts_number < var->cnsts_size, "Too much constraints");
+  xbt_assert(var->cnsts.size() < var->cnsts.capacity(), "Too much constraints");
 
-  lmm_element_t elem = &(var->cnsts[var->cnsts_number++]);
+  var->cnsts.resize(var->cnsts.size() + 1);
+  s_lmm_element_t& elem = var->cnsts.back();
 
-  elem->consumption_weight = consumption_weight;
-  elem->constraint = cnst;
-  elem->variable = var;
+  elem.consumption_weight = consumption_weight;
+  elem.constraint         = cnst;
+  elem.variable           = var;
 
   if (var->sharing_weight) {
-    xbt_swag_insert_at_head(elem, &(elem->constraint->enabled_element_set));
-    lmm_increase_concurrency(elem);
+    xbt_swag_insert_at_head(&elem, &(elem.constraint->enabled_element_set));
+    lmm_increase_concurrency(&elem);
   } else
-    xbt_swag_insert_at_tail(elem, &(elem->constraint->disabled_element_set));
+    xbt_swag_insert_at_tail(&elem, &(elem.constraint->disabled_element_set));
 
   if (not sys->selective_update_active) {
     make_constraint_active(sys, cnst);
-  } else if (elem->consumption_weight > 0 || var->sharing_weight > 0) {
+  } else if (elem.consumption_weight > 0 || var->sharing_weight > 0) {
     make_constraint_active(sys, cnst);
     lmm_update_modified_set(sys, cnst);
     //TODOLATER: Why do we need this second call?
-    if (var->cnsts_number > 1)
+    if (var->cnsts.size() > 1)
       lmm_update_modified_set(sys, var->cnsts[0].constraint);
   }
 
@@ -502,36 +401,34 @@ void lmm_expand(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, dou
 
 void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var, double value)
 {
-  int i;
   sys->modified = 1;
 
   lmm_check_concurrency(sys);
 
   //BEWARE: In case you have multiple elements in one constraint, this will always add value to the first element.
-  for (i = 0; i < var->cnsts_number; i++)
-    if (var->cnsts[i].constraint == cnst)
-      break;
-
-  if (i < var->cnsts_number) {
+  auto elem_it = std::find_if(begin(var->cnsts), end(var->cnsts),
+                              [&cnst](s_lmm_element_t const& x) { return x.constraint == cnst; });
+  if (elem_it != end(var->cnsts)) {
+    s_lmm_element_t& elem = *elem_it;
     if (var->sharing_weight)
-      lmm_decrease_concurrency(&var->cnsts[i]);
+      lmm_decrease_concurrency(&elem);
 
     if (cnst->sharing_policy)
-      var->cnsts[i].consumption_weight += value;
+      elem.consumption_weight += value;
     else
-      var->cnsts[i].consumption_weight = MAX(var->cnsts[i].consumption_weight, value);
+      elem.consumption_weight = std::max(elem.consumption_weight, value);
 
     //We need to check that increasing value of the element does not cross the concurrency limit
     if (var->sharing_weight) {
-      if(lmm_concurrency_slack(cnst)<lmm_element_concurrency(&var->cnsts[i])){
+      if (lmm_concurrency_slack(cnst) < lmm_element_concurrency(&elem)) {
         double weight = var->sharing_weight;
         lmm_disable_var(sys,var);
-        for (int j = 0; j < var->cnsts_number; j++)
-          lmm_on_disabled_var(sys,var->cnsts[j].constraint);
+        for (s_lmm_element_t const& elem2 : var->cnsts)
+          lmm_on_disabled_var(sys, elem2.constraint);
         var->staged_weight=weight;
         xbt_assert(not var->sharing_weight);
       }
-      lmm_increase_concurrency(&var->cnsts[i]);
+      lmm_increase_concurrency(&elem);
     }
     lmm_update_modified_set(sys, cnst);
   } else
@@ -540,17 +437,17 @@ void lmm_expand_add(lmm_system_t sys, lmm_constraint_t cnst, lmm_variable_t var,
   lmm_check_concurrency(sys);
 }
 
-lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t /*sys*/, lmm_variable_t var, int num)
+lmm_constraint_t lmm_get_cnst_from_var(lmm_system_t /*sys*/, lmm_variable_t var, unsigned num)
 {
-  if (num < var->cnsts_number)
+  if (num < var->cnsts.size())
     return (var->cnsts[num].constraint);
   else
     return nullptr;
 }
 
-double lmm_get_cnst_weight_from_var(lmm_system_t /*sys*/, lmm_variable_t var, int num)
+double lmm_get_cnst_weight_from_var(lmm_system_t /*sys*/, lmm_variable_t var, unsigned num)
 {
-  if (num < var->cnsts_number)
+  if (num < var->cnsts.size())
     return (var->cnsts[num].consumption_weight);
   else
     return 0.0;
@@ -558,7 +455,7 @@ double lmm_get_cnst_weight_from_var(lmm_system_t /*sys*/, lmm_variable_t var, in
 
 int lmm_get_number_of_cnst_from_var(lmm_system_t /*sys*/, lmm_variable_t var)
 {
-  return (var->cnsts_number);
+  return (var->cnsts.size());
 }
 
 lmm_variable_t lmm_get_var_from_cnst(lmm_system_t /*sys*/, lmm_constraint_t cnst, lmm_element_t * elem)
@@ -629,40 +526,29 @@ void *lmm_variable_id(lmm_variable_t var)
 }
 
 static inline void saturated_constraint_set_update(double usage, int cnst_light_num,
-                                                   dyn_light_t saturated_constraint_set, double *min_usage)
+                                                   dyn_light_t& saturated_constraint_set, double* min_usage)
 {
   xbt_assert(usage > 0,"Impossible");
 
   if (*min_usage < 0 || *min_usage > usage) {
     *min_usage = usage;
     XBT_HERE(" min_usage=%f (cnst->remaining / cnst->usage =%f)", *min_usage, usage);
-    saturated_constraint_set->data[0] = cnst_light_num;
-    saturated_constraint_set->pos = 1;
+    saturated_constraint_set.assign(1, cnst_light_num);
   } else if (*min_usage == usage) {
-    if(saturated_constraint_set->pos == saturated_constraint_set->size) { // realloc the size
-      saturated_constraint_set->size *= 2;
-      saturated_constraint_set->data =
-        (int*) xbt_realloc(saturated_constraint_set->data, (saturated_constraint_set->size) * sizeof(int));
-    }
-    saturated_constraint_set->data[saturated_constraint_set->pos] = cnst_light_num;
-    saturated_constraint_set->pos++;
+    saturated_constraint_set.emplace_back(cnst_light_num);
   }
 }
 
-static inline void saturated_variable_set_update(s_lmm_constraint_light_t *cnst_light_tab,
-                                                 dyn_light_t saturated_constraint_set, lmm_system_t sys)
+static inline void saturated_variable_set_update(s_lmm_constraint_light_t* cnst_light_tab,
+                                                 const dyn_light_t& saturated_constraint_set, lmm_system_t sys)
 {
   /* Add active variables (i.e. variables that need to be set) from the set of constraints to saturate (cnst_light_tab)*/
-  lmm_constraint_light_t cnst = nullptr;
-  void *_elem;
-  lmm_element_t elem = nullptr;
-  xbt_swag_t elem_list = nullptr;
-  int i;
-  for(i = 0; i< saturated_constraint_set->pos; i++){
-    cnst = &cnst_light_tab[saturated_constraint_set->data[i]];
-    elem_list = &(cnst->cnst->active_element_set);
+  for (int const& saturated_cnst : saturated_constraint_set) {
+    lmm_constraint_light_t cnst = &cnst_light_tab[saturated_cnst];
+    void* _elem;
+    xbt_swag_t elem_list = &(cnst->cnst->active_element_set);
     xbt_swag_foreach(_elem, elem_list) {
-      elem = (lmm_element_t)_elem;
+      lmm_element_t elem = (lmm_element_t)_elem;
       //Visiting active_element_set, so, by construction, should never get a zero weight, correct?
       xbt_assert(elem->variable->sharing_weight > 0);
       if (elem->consumption_weight > 0)
@@ -705,7 +591,7 @@ void lmm_print(lmm_system_t sys)
       if(cnst->sharing_policy)
         sum += elem->consumption_weight * elem->variable->value;
       else
-        sum = MAX(sum, elem->consumption_weight * elem->variable->value);
+        sum = std::max(sum, elem->consumption_weight * elem->variable->value);
     }
     //TODO: Adding disabled elements only for test compatibility, but do we really want them to be printed?
     elem_list = &(cnst->disabled_element_set);
@@ -716,7 +602,7 @@ void lmm_print(lmm_system_t sys)
       if(cnst->sharing_policy)
         sum += elem->consumption_weight * elem->variable->value;
       else
-        sum = MAX(sum, elem->consumption_weight * elem->variable->value);
+        sum = std::max(sum, elem->consumption_weight * elem->variable->value);
     }
 
     buf = buf + "0) <= " + std::to_string(cnst->bound) + " ('" + std::to_string(cnst->id_int) + "')";
@@ -767,7 +653,6 @@ void lmm_solve(lmm_system_t sys)
   xbt_swag_foreach(_cnst, cnst_list) {
     lmm_constraint_t cnst = (lmm_constraint_t)_cnst;
     xbt_swag_t elem_list  = &(cnst->enabled_element_set);
-    //XBT_DEBUG("Variable set : %d", xbt_swag_size(elem_list));
     xbt_swag_foreach(_elem, elem_list) {
       lmm_variable_t var = ((lmm_element_t)_elem)->variable;
       xbt_assert(var->sharing_weight > 0.0);
@@ -775,12 +660,9 @@ void lmm_solve(lmm_system_t sys)
     }
   }
 
-  s_lmm_constraint_light_t *cnst_light_tab =
-     (s_lmm_constraint_light_t *)xbt_malloc0(xbt_swag_size(cnst_list)*sizeof(s_lmm_constraint_light_t));
+  s_lmm_constraint_light_t* cnst_light_tab = new s_lmm_constraint_light_t[xbt_swag_size(cnst_list)]();
   int cnst_light_num = 0;
-  dyn_light_t saturated_constraint_set = xbt_new0(s_dyn_light_t,1);
-  saturated_constraint_set->size = 5;
-  saturated_constraint_set->data = xbt_new0(int, saturated_constraint_set->size);
+  dyn_light_t saturated_constraint_set;
 
   xbt_swag_foreach_safe(_cnst, _cnst_next, cnst_list) {
     lmm_constraint_t cnst = (lmm_constraint_t)_cnst;
@@ -840,19 +722,16 @@ void lmm_solve(lmm_system_t sys)
         if (min_bound < 0)
           min_bound = var->bound * var->sharing_weight;
         else
-          min_bound = MIN(min_bound, (var->bound * var->sharing_weight));
+          min_bound = std::min(min_bound, (var->bound * var->sharing_weight));
         XBT_DEBUG("Updated min_bound=%f", min_bound);
       }
     }
 
     while ((var = (lmm_variable_t)xbt_swag_getFirst(var_list))) {
-      int i;
-
       if (min_bound < 0) {
         //If no variable could reach its bound, deal iteratively the constraints usage ( at worst one constraint is
         // saturated at each cycle)
         var->value = min_usage / var->sharing_weight;
-        // XBT_DEBUG("Setting %p (%d) value to %f\n", var, var->id_int, var->value);
         XBT_DEBUG("Setting var (%d) value to %f\n", var->id_int, var->value);
       } else {
          //If there exist a variable that can reach its bound, only update it (and other with the same bound) for now.
@@ -870,23 +749,19 @@ void lmm_solve(lmm_system_t sys)
                 var->id_int, var->value);
 
       /* Update the usage of contraints where this variable is involved */
-      for (i = 0; i < var->cnsts_number; i++) {
-        lmm_element_t elem    = &var->cnsts[i];
-        lmm_constraint_t cnst = elem->constraint;
+      for (s_lmm_element_t& elem : var->cnsts) {
+        lmm_constraint_t cnst = elem.constraint;
         if (cnst->sharing_policy) {
-          //Remember: shared constraints require that sum(elem->value * var->value) < cnst->bound
-          double_update(&(cnst->remaining), elem->consumption_weight * var->value, cnst->bound * sg_maxmin_precision);
-          double_update(&(cnst->usage), elem->consumption_weight / var->sharing_weight, sg_maxmin_precision);
-          //If the constraint is saturated, remove it from the set of active constraints (light_tab)
+          // Remember: shared constraints require that sum(elem.value * var->value) < cnst->bound
+          double_update(&(cnst->remaining), elem.consumption_weight * var->value, cnst->bound * sg_maxmin_precision);
+          double_update(&(cnst->usage), elem.consumption_weight / var->sharing_weight, sg_maxmin_precision);
+          // If the constraint is saturated, remove it from the set of active constraints (light_tab)
           if (not double_positive(cnst->usage, sg_maxmin_precision) ||
               not double_positive(cnst->remaining, cnst->bound * sg_maxmin_precision)) {
             if (cnst->cnst_light) {
               int index = (cnst->cnst_light-cnst_light_tab);
               XBT_DEBUG("index: %d \t cnst_light_num: %d \t || usage: %f remaining: %f bound: %f  ",
                          index,cnst_light_num, cnst->usage, cnst->remaining, cnst->bound);
-              //XBT_DEBUG("index: %d \t cnst_light_num: %d \t || \t cnst: %p \t cnst->cnst_light: %p "
-              //          "\t cnst_light_tab: %p usage: %f remaining: %f bound: %f  ", index,cnst_light_num,
-              //          cnst, cnst->cnst_light, cnst_light_tab, cnst->usage, cnst->remaining, cnst->bound);
               cnst_light_tab[index]=cnst_light_tab[cnst_light_num-1];
               cnst_light_tab[index].cnst->cnst_light = &cnst_light_tab[index];
               cnst_light_num--;
@@ -895,18 +770,19 @@ void lmm_solve(lmm_system_t sys)
           } else {
             cnst->cnst_light->remaining_over_usage = cnst->remaining / cnst->usage;
           }
-          make_elem_inactive(elem);
+          make_elem_inactive(&elem);
         } else {
-          //Remember: non-shared constraints only require that max(elem->value * var->value) < cnst->bound
+          // Remember: non-shared constraints only require that max(elem.value * var->value) < cnst->bound
           cnst->usage = 0.0;
-          make_elem_inactive(elem);
+          make_elem_inactive(&elem);
           xbt_swag_t elem_list = &(cnst->enabled_element_set);
           xbt_swag_foreach(_elem, elem_list) {
-            elem = (lmm_element_t)_elem;
-            xbt_assert(elem->variable->sharing_weight > 0);
-            if (elem->variable->value > 0) continue;
-            if (elem->consumption_weight > 0)
-              cnst->usage = MAX(cnst->usage, elem->consumption_weight / elem->variable->sharing_weight);
+            lmm_element_t elem2 = static_cast<lmm_element_t>(_elem);
+            xbt_assert(elem2->variable->sharing_weight > 0);
+            if (elem2->variable->value > 0)
+              continue;
+            if (elem2->consumption_weight > 0)
+              cnst->usage = std::max(cnst->usage, elem2->consumption_weight / elem2->variable->sharing_weight);
           }
           //If the constraint is saturated, remove it from the set of active constraints (light_tab)
           if (not double_positive(cnst->usage, sg_maxmin_precision) ||
@@ -934,7 +810,7 @@ void lmm_solve(lmm_system_t sys)
     /* Find out which variables reach the maximum */
     min_usage = -1;
     min_bound = -1;
-    saturated_constraint_set->pos = 0;
+    saturated_constraint_set.clear();
     int pos;
     for(pos=0; pos<cnst_light_num; pos++){
       xbt_assert(cnst_light_tab[pos].cnst->active_element_set.count>0, "Cannot saturate more a constraint that has"
@@ -960,9 +836,7 @@ void lmm_solve(lmm_system_t sys)
 
   lmm_check_concurrency(sys);
 
-  xbt_free(saturated_constraint_set->data);
-  xbt_free(saturated_constraint_set);
-  xbt_free(cnst_light_tab);
+  delete[] cnst_light_tab;
   XBT_OUT();
 }
 
@@ -980,33 +854,30 @@ void lmm_update_variable_bound(lmm_system_t sys, lmm_variable_t var, double boun
   sys->modified = 1;
   var->bound = bound;
 
-  if (var->cnsts_number)
+  if (not var->cnsts.empty())
     lmm_update_modified_set(sys, var->cnsts[0].constraint);
 }
 
-int lmm_concurrency_slack(lmm_constraint_t cnstr){
-  //FIXME MARTIN: Replace by infinite value std::numeric_limits<int>::(max)(), or something better within Simgrid?
-  if(cnstr->concurrency_limit<0)
-    return 666;
-
+int lmm_concurrency_slack(lmm_constraint_t cnstr)
+{
+  if (cnstr->concurrency_limit < 0)
+    return std::numeric_limits<int>::max();
   return  cnstr->concurrency_limit - cnstr->concurrency_current;
 }
 
 /** \brief Measure the minimum concurrency slack across all constraints where the given var is involved */
-int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var){
+int lmm_cnstrs_min_concurrency_slack(lmm_variable_t var)
+{
   int minslack = std::numeric_limits<int>::max();
-  for (int i = 0; i < var->cnsts_number; i++) {
-    int slack = lmm_concurrency_slack(var->cnsts[i].constraint);
-
-    //This is only an optimization, to avoid looking at more constraints when slack is already zero
-    //Disable it when debugging to let lmm_concurrency_slack catch nasty things
-    if (not slack && not XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug))
-      return 0;
-
-    if(minslack>slack)
-      minslack=slack;
+  for (s_lmm_element_t const& elem : var->cnsts) {
+    int slack = lmm_concurrency_slack(elem.constraint);
+    if (slack < minslack) {
+      // This is only an optimization, to avoid looking at more constraints when slack is already zero
+      if (slack == 0)
+        return 0;
+      minslack = slack;
+    }
   }
-
   return minslack;
 }
 
@@ -1023,7 +894,7 @@ int lmm_can_enable_var(lmm_variable_t var){
 //A priori not a big performance issue, but we might do better by calling lmm_update_modified_set within the for loops
 // (after doing the first for enabling==1, and before doing the last for disabling==1)
 void lmm_enable_var(lmm_system_t sys, lmm_variable_t var){
-  xbt_assert(lmm_can_enable_var(var));
+  xbt_assert(not XBT_LOG_ISENABLED(surf_maxmin, xbt_log_priority_debug) || lmm_can_enable_var(var));
 
   var->sharing_weight = var->staged_weight;
   var->staged_weight = 0;
@@ -1033,19 +904,17 @@ void lmm_enable_var(lmm_system_t sys, lmm_variable_t var){
 
   xbt_swag_remove(var, &(sys->variable_set));
   xbt_swag_insert_at_head(var, &(sys->variable_set));
-  for (int i = 0; i < var->cnsts_number; i++) {
-    lmm_element_t elem = &var->cnsts[i];
-    xbt_swag_remove(elem, &(elem->constraint->disabled_element_set));
-    xbt_swag_insert_at_head(elem, &(elem->constraint->enabled_element_set));
-    lmm_increase_concurrency(elem);
+  for (s_lmm_element_t& elem : var->cnsts) {
+    xbt_swag_remove(&elem, &(elem.constraint->disabled_element_set));
+    xbt_swag_insert_at_head(&elem, &(elem.constraint->enabled_element_set));
+    lmm_increase_concurrency(&elem);
   }
-  if (var->cnsts_number)
+  if (not var->cnsts.empty())
     lmm_update_modified_set(sys, var->cnsts[0].constraint);
 
   //When used within lmm_on_disabled_var, we would get an assertion fail, because transiently there can be variables
   // that are staged and could be activated.
   //Anyway, caller functions all call lmm_check_concurrency() in the end.
-  //  lmm_check_concurrency(sys);
 }
 
 void lmm_disable_var(lmm_system_t sys, lmm_variable_t var){
@@ -1054,16 +923,15 @@ void lmm_disable_var(lmm_system_t sys, lmm_variable_t var){
   // moving the last element of var.
   xbt_swag_remove(var, &(sys->variable_set));
   xbt_swag_insert_at_tail(var, &(sys->variable_set));
-  if (var->cnsts_number)
+  if (not var->cnsts.empty())
     lmm_update_modified_set(sys, var->cnsts[0].constraint);
-  for (int i = 0; i < var->cnsts_number; i++) {
-    lmm_element_t elem = &var->cnsts[i];
-    xbt_swag_remove(elem, &(elem->constraint->enabled_element_set));
-    xbt_swag_insert_at_tail(elem, &(elem->constraint->disabled_element_set));
+  for (s_lmm_element_t& elem : var->cnsts) {
+    xbt_swag_remove(&elem, &(elem.constraint->enabled_element_set));
+    xbt_swag_insert_at_tail(&elem, &(elem.constraint->disabled_element_set));
 
-    xbt_swag_remove(elem, &(elem->constraint->active_element_set));
+    xbt_swag_remove(&elem, &(elem.constraint->active_element_set));
 
-    lmm_decrease_concurrency(elem);
+    lmm_decrease_concurrency(&elem);
   }
 
   var->sharing_weight = 0.0;
@@ -1095,13 +963,11 @@ void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr){
 
     lmm_element_t nextelem = (lmm_element_t)xbt_swag_getNext(elem, cnstr->disabled_element_set.offset);
 
-    if (elem->variable->staged_weight>0 ){
+    if (elem->variable->staged_weight > 0 && lmm_can_enable_var(elem->variable)) {
       //Found a staged variable
       //TODOLATER: Add random timing function to model reservation protocol fuzziness? Then how to make sure that
       //staged variables will eventually be called?
-      if(lmm_can_enable_var(elem->variable)){
-        lmm_enable_var(sys,elem->variable);
-      }
+      lmm_enable_var(sys, elem->variable);
     }
 
     xbt_assert(cnstr->concurrency_current<=cnstr->concurrency_limit,"Concurrency overflow!");
@@ -1114,7 +980,6 @@ void lmm_on_disabled_var(lmm_system_t sys, lmm_constraint_t cnstr){
   //We could get an assertion fail, because transiently there can be variables that are staged and could be activated.
   //And we need to go through all constraints of the disabled var before getting back a coherent state.
   //Anyway, caller functions all call lmm_check_concurrency() in the end.
-  //  lmm_check_concurrency(sys);
 }
 
 /* \brief update the weight of a variable, and enable/disable it.
@@ -1174,16 +1039,6 @@ int lmm_constraint_used(lmm_system_t sys, lmm_constraint_t cnst)
   return xbt_swag_belongs(cnst, &(sys->active_constraint_set));
 }
 
-inline lmm_constraint_t lmm_get_first_active_constraint(lmm_system_t sys)
-{
-  return (lmm_constraint_t)xbt_swag_getFirst(&(sys->active_constraint_set));
-}
-
-inline lmm_constraint_t lmm_get_next_active_constraint(lmm_system_t sys, lmm_constraint_t cnst)
-{
-  return (lmm_constraint_t)xbt_swag_getNext(cnst, (sys->active_constraint_set).offset);
-}
-
 /** \brief Update the constraint set propagating recursively to other constraints so the system should not be entirely
  *  computed.
  *
@@ -1197,15 +1052,14 @@ static void lmm_update_modified_set_rec(lmm_system_t sys, lmm_constraint_t cnst)
 {
   void* _elem;
 
-  //TODOLATER: Why lmm_modified_set has been changed in git version 2392B5157...? Looks equivalent logically and less obvious..
   xbt_swag_foreach(_elem, &cnst->enabled_element_set) {
     lmm_variable_t var = ((lmm_element_t)_elem)->variable;
-    s_lmm_element_t *cnsts = var->cnsts;
-    int i;
-    for (i = 0; var->visited != sys->visited_counter && i < var->cnsts_number ; i++) {
-      if (cnsts[i].constraint != cnst && not xbt_swag_belongs(cnsts[i].constraint, &sys->modified_constraint_set)) {
-        xbt_swag_insert(cnsts[i].constraint, &sys->modified_constraint_set);
-        lmm_update_modified_set_rec(sys, cnsts[i].constraint);
+    for (s_lmm_element_t const& elem : var->cnsts) {
+      if (var->visited == sys->visited_counter)
+        break;
+      if (elem.constraint != cnst && not xbt_swag_belongs(elem.constraint, &sys->modified_constraint_set)) {
+        xbt_swag_insert(elem.constraint, &sys->modified_constraint_set);
+        lmm_update_modified_set_rec(sys, elem.constraint);
       }
     }
     //var will be ignored in later visits as long as sys->visited_counter does not move
@@ -1228,11 +1082,11 @@ static void lmm_update_modified_set(lmm_system_t sys, lmm_constraint_t cnst)
  */
 static void lmm_remove_all_modified_set(lmm_system_t sys)
 {
-  //We cleverly un-flag all variables just by incrementing sys->visited_counter
-  //In effect, the var->visited value will no more be equal to sys->visited counter
-  //To be clean, when visited counter has wrapped around, we force these var->visited values so that variables that
-  //were in the modified a long (long long) time ago are not wrongly skipped here, which would lead to very nasty bugs
-  //(i.e. not readibily reproducible, and requiring a lot of run time before happening).
+  // We cleverly un-flag all variables just by incrementing sys->visited_counter
+  // In effect, the var->visited value will no more be equal to sys->visited counter
+  // To be clean, when visited counter has wrapped around, we force these var->visited values so that variables that
+  // were in the modified a long long time ago are not wrongly skipped here, which would lead to very nasty bugs
+  // (i.e. not readibily reproducible, and requiring a lot of run time before happening).
   if (++sys->visited_counter == 1) {
     /* the counter wrapped around, reset each variable->visited */
   void *_var;