namespace simgrid {
namespace mc {
+// Free functions
+
+static void mc_frame_free(void* frame)
+{
+ delete (simgrid::mc::Frame*)frame;
+}
+
+static void mc_type_free(void* t)
+{
+ delete (simgrid::mc::Type*)t;
+}
+
// Type
Type::Type()
{
this->type = 0;
this->id = 0;
- this->name = std::string();
this->byte_size = 0;
this->element_count = 0;
- this->members = nullptr;
this->is_pointer_type = 0;
- this->location = {0, 0, 0, 0};
- this->offset = 0;
+ this->type_id = 0;
this->subtype = nullptr;
this->full_type = nullptr;
}
-Type::~Type()
+// Type
+
+Variable::Variable()
{
- xbt_dynar_free(&this->members);
- mc_dwarf_expression_clear(&this->location);
+ this->dwarf_offset = 0;
+ this->global = 0;
+ this->type = nullptr;
+ this->type_id = 0;
+ this->address = nullptr;
+ this->start_scope = 0;
+ this->object_info = nullptr;
+}
+
+// Frame
+
+Frame::Frame()
+{
+ this->tag = 0;
+ this->low_pc = nullptr;
+ this->high_pc = nullptr;
+ this->id = 0;
+ this->abstract_origin_id = 0;
+ this->object_info = nullptr;
}
// ObjectInformations
-dw_frame_t ObjectInformation::find_function(const void *ip) const
+ObjectInformation::ObjectInformation()
+{
+ this->flags = 0;
+ this->start = nullptr;
+ this->end = nullptr;
+ this->start_exec = nullptr;
+ this->end_exec = nullptr;
+ this->start_rw = nullptr;
+ this->end_rw = nullptr;
+ this->start_ro = nullptr;
+ this->end_ro = nullptr;
+}
+
+/** Find the DWARF offset for this ELF object
+ *
+ * An offset is applied to address found in DWARF:
+ *
+ * * for an executable obejct, addresses are virtual address
+ * (there is no offset) i.e.
+ * \f$\text{virtual address} = \{dwarf address}\f$;
+ *
+ * * for a shared object, the addreses are offset from the begining
+ * of the shared object (the base address of the mapped shared
+ * object must be used as offset
+ * i.e. \f$\text{virtual address} = \text{shared object base address}
+ * + \text{dwarf address}\f$.
+ */
+void *ObjectInformation::base_address() const
+{
+ if (this->executable())
+ return nullptr;
+
+ void *result = this->start_exec;
+ if (this->start_rw != NULL && result > (void *) this->start_rw)
+ result = this->start_rw;
+ if (this->start_ro != NULL && result > (void *) this->start_ro)
+ result = this->start_ro;
+ return result;
+}
+
+/* Find a function by instruction pointer */
+simgrid::mc::Frame* ObjectInformation::find_function(const void *ip) const
{
- xbt_dynar_t dynar = this->functions_index;
- mc_function_index_item_t base =
- (mc_function_index_item_t) xbt_dynar_get_ptr(dynar, 0);
+ /* This is implemented by binary search on a sorted array.
+ *
+ * We do quite a lot ot those so we want this to be cache efficient.
+ * We pack the only information we need in the index entries in order
+ * to successfully do the binary search. We do not need the high_pc
+ * during the binary search (only at the end) so it is not included
+ * in the index entry. We could use parallel arrays as well.
+ *
+ * We cannot really use the std:: alogrithm for this.
+ * We could use std::binary_search by including the high_pc inside
+ * the FunctionIndexEntry.
+ */
+ const simgrid::mc::FunctionIndexEntry* base =
+ this->functions_index.data();
int i = 0;
- int j = xbt_dynar_length(dynar) - 1;
+ int j = this->functions_index.size() - 1;
while (j >= i) {
int k = i + ((j - i) / 2);
- if (ip < base[k].low_pc) {
+
+ /* In most of the search, we do not dereference the base[k].function.
+ * This way the memory accesses are located in the base[k] array. */
+ if (ip < base[k].low_pc)
j = k - 1;
- } else if (ip >= base[k].high_pc) {
+ else if (k < j && ip >= base[k + 1].low_pc)
i = k + 1;
- } else {
+
+ /* At this point, the search is over.
+ * Either we have found the correct function or we do not know
+ * any function corresponding to this instruction address.
+ * Only at the point do we derefernce the function pointer. */
+ else if (ip < base[k].function->high_pc)
return base[k].function;
- }
+ else
+ return nullptr;
}
return nullptr;
}
-dw_variable_t ObjectInformation::find_variable(const char* name) const
+simgrid::mc::Variable* ObjectInformation::find_variable(const char* name) const
{
- unsigned int cursor = 0;
- dw_variable_t variable;
- xbt_dynar_foreach(this->global_variables, cursor, variable){
- if(!strcmp(name, variable->name))
- return variable;
- }
-
+ for (simgrid::mc::Variable& variable : this->global_variables)
+ if(variable.name == name)
+ return &variable;
return nullptr;
}
