+
+namespace simgrid {
+namespace mc {
+
+/** A hash which works with more stuff
+ *
+ * It can hash pairs: the standard hash currently doesn't include this.
+ */
+template<class X> struct hash : public std::hash<X> {};
+
+template<class X, class Y>
+struct hash<std::pair<X,Y>> {
+ std::size_t operator()(std::pair<X,Y>const& x) const
+ {
+ struct hash<X> h1;
+ struct hash<X> h2;
+ return h1(x.first) ^ h2(x.second);
+ }
+};
+
+struct ComparisonState {
+ std::unordered_set<std::pair<void*, void*>, hash<std::pair<void*, void*>>> compared_pointers;
+};
+
+}
+}
+
+using simgrid::mc::ComparisonState;
+
+/************************** Snapshot comparison *******************************/
+/******************************************************************************/
+
+static int compare_areas_with_type(ComparisonState& state,
+ int process_index,
+ void* real_area1, simgrid::mc::Snapshot* snapshot1, mc_mem_region_t region1,
+ void* real_area2, simgrid::mc::Snapshot* snapshot2, mc_mem_region_t region2,
+ simgrid::mc::Type* type, int pointer_level)
+{
+ simgrid::mc::Process* process = &mc_model_checker->process();
+
+ simgrid::mc::Type* subtype;
+ simgrid::mc::Type* subsubtype;
+ int elm_size, i, res;
+
+ top:
+ 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 MC_snapshot_region_memcmp(
+ real_area1, region1, real_area2, region2,
+ type->byte_size) != 0;
+ }
+ case DW_TAG_typedef:
+ case DW_TAG_volatile_type:
+ case DW_TAG_const_type:
+ // Poor man's TCO:
+ type = type->subtype;
+ goto top;
+ 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 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:
+ return 0;
+ break;
+ }
+ for (i = 0; i < type->element_count; i++) {
+ size_t off = i * elm_size;
+ res = compare_areas_with_type(state, process_index,
+ (char*) real_area1 + off, snapshot1, region1,
+ (char*) real_area2 + off, snapshot2, region2,
+ type->subtype, pointer_level);
+ if (res == 1)
+ return res;
+ }
+ break;
+ case DW_TAG_pointer_type:
+ case DW_TAG_reference_type:
+ case DW_TAG_rvalue_reference_type:
+ {
+ void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
+ void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
+
+ if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
+ return (addr_pointed1 != addr_pointed2);
+ if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
+ return 0;
+ if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
+ return 1;
+ if (!state.compared_pointers.insert(
+ std::make_pair(addr_pointed1, addr_pointed2)).second)
+ return 0;
+
+ pointer_level++;
+
+ // 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 > process->heap_address
+ && addr_pointed1 < mc_snapshot_get_heap_end(snapshot1)) {
+ if (!
+ (addr_pointed2 > process->heap_address
+ && addr_pointed2 < mc_snapshot_get_heap_end(snapshot2)))
+ return 1;
+ // The pointers are both in the heap:
+ return simgrid::mc::compare_heap_area(process_index, addr_pointed1, addr_pointed2, snapshot1,
+ snapshot2, nullptr, type->subtype, pointer_level);
+ }
+
+ // The pointers are both in the current object R/W segment:
+ else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
+ if (!region2->contain(simgrid::mc::remote(addr_pointed2)))
+ return 1;
+ if (!type->type_id)
+ return (addr_pointed1 != addr_pointed2);
+ else
+ return compare_areas_with_type(state, process_index,
+ addr_pointed1, snapshot1, region1,
+ addr_pointed2, snapshot2, region2,
+ type->subtype, pointer_level);
+ }
+
+ // TODO, We do not handle very well the case where
+ // it belongs to a different (non-heap) region from the current one.
+
+ else
+ return (addr_pointed1 != addr_pointed2);
+
+ break;
+ }
+ case DW_TAG_structure_type:
+ case DW_TAG_class_type:
+ for(simgrid::mc::Member& member : type->members) {
+ void *member1 = simgrid::dwarf::resolve_member(
+ real_area1, type, &member, snapshot1, process_index);
+ void *member2 = simgrid::dwarf::resolve_member(
+ real_area2, type, &member, snapshot2, process_index);
+ mc_mem_region_t subregion1 = mc_get_region_hinted(member1, snapshot1, process_index, region1);
+ mc_mem_region_t subregion2 = mc_get_region_hinted(member2, snapshot2, process_index, region2);
+ res =
+ compare_areas_with_type(state, process_index,
+ member1, snapshot1, subregion1,
+ member2, snapshot2, subregion2,
+ member.type, pointer_level);
+ if (res == 1)
+ return res;
+ }
+ break;
+ case DW_TAG_subroutine_type:
+ return -1;
+ break;
+ default:
+ XBT_VERB("Unknown case : %d", type->type);
+ break;
+ }
+
+ return 0;
+}
+
+static int compare_global_variables(simgrid::mc::ObjectInformation* object_info,
+ int process_index,
+ mc_mem_region_t r1,
+ mc_mem_region_t r2, simgrid::mc::Snapshot* snapshot1,
+ simgrid::mc::Snapshot* snapshot2)
+{
+ xbt_assert(r1 && r2, "Missing region.");
+
+#if HAVE_SMPI
+ if (r1->storage_type() == simgrid::mc::StorageType::Privatized) {
+ xbt_assert(process_index >= 0);
+ if (r2->storage_type() != simgrid::mc::StorageType::Privatized)
+ return 1;
+
+ size_t process_count = MC_smpi_process_count();
+ xbt_assert(process_count == r1->privatized_data().size()
+ && process_count == r2->privatized_data().size());
+
+ // Compare the global variables separately for each simulates process:
+ for (size_t process_index = 0; process_index < process_count; process_index++) {
+ int is_diff = compare_global_variables(object_info, process_index,
+ &r1->privatized_data()[process_index],
+ &r2->privatized_data()[process_index],
+ snapshot1, snapshot2);
+ if (is_diff) return 1;
+ }
+ return 0;
+ }
+#else
+ xbt_assert(r1->storage_type() != simgrid::mc::StorageType::Privatized);
+#endif
+ xbt_assert(r2->storage_type() != simgrid::mc::StorageType::Privatized);
+
+ ComparisonState state;
+
+ std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
+
+ for (simgrid::mc::Variable& current_var : variables) {
+
+ // 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;
+
+ simgrid::mc::Type* bvariable_type = current_var.type;
+ int res =
+ compare_areas_with_type(state, process_index,
+ (char *) current_var.address, snapshot1, r1,
+ (char *) current_var.address, snapshot2, r2,
+ bvariable_type, 0);
+ if (res == 1) {
+ XBT_VERB("Global variable %s (%p) is different between snapshots",
+ current_var.name.c_str(),
+ (char *) current_var.address);
+ return 1;
+ }
+
+ }
+
+ return 0;
+
+}
+
+static int compare_local_variables(int process_index,
+ simgrid::mc::Snapshot* snapshot1,
+ simgrid::mc::Snapshot* snapshot2,
+ mc_snapshot_stack_t stack1,
+ mc_snapshot_stack_t stack2)
+{
+ ComparisonState state;
+
+ if (stack1->local_variables.size() != stack2->local_variables.size()) {
+ XBT_VERB("Different number of local variables");
+ return 1;
+ }
+
+ unsigned int cursor = 0;
+ local_variable_t current_var1, current_var2;
+ int res;
+ while (cursor < stack1->local_variables.size()) {
+ current_var1 = &stack1->local_variables[cursor];
+ current_var2 = &stack1->local_variables[cursor];
+ if (current_var1->name != current_var2->name
+ || current_var1->subprogram != current_var2->subprogram
+ || current_var1->ip != current_var2->ip) {
+ // 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.c_str(),
+ current_var2->name.c_str(),
+ current_var1->subprogram->name.c_str(),
+ current_var2->subprogram->name.c_str(),
+ current_var1->ip, current_var2->ip);
+ return 1;
+ }
+ // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
+
+ simgrid::mc::Type* subtype = current_var1->type;
+ res =
+ compare_areas_with_type(state, process_index,
+ current_var1->address, snapshot1, mc_get_snapshot_region(current_var1->address, snapshot1, process_index),
+ current_var2->address, snapshot2, mc_get_snapshot_region(current_var2->address, snapshot2, process_index),
+ subtype, 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.c_str(),
+ current_var1->address,
+ current_var2->address,
+ current_var1->subprogram->name.c_str());
+ return res;
+ }
+ cursor++;
+ }
+ return 0;
+}
+
+namespace simgrid {
+namespace mc {
+
+int snapshot_compare(int num1, simgrid::mc::Snapshot* s1, int num2, simgrid::mc::Snapshot* s2)
+{
+ simgrid::mc::Process* process = &mc_model_checker->process();
+
+ int errors = 0;
+ int res_init;
+
+ 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 */
+ if (s1->enabled_processes != s2->enabled_processes) {
+ XBT_VERB("(%d - %d) Different enabled processes", num1, num2);
+ // return 1; ??
+ }
+
+ unsigned long i = 0;
+ size_t size_used1, size_used2;
+ int is_diff = 0;
+
+ /* Compare size of stacks */
+ while (i < s1->stacks.size()) {
+ size_used1 = s1->stack_sizes[i];
+ size_used2 = s2->stack_sizes[i];
+ if (size_used1 != size_used2) {
+#ifdef MC_DEBUG
+ 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", num1,
+ num2, size_used1, size_used2);
+#endif
+ return 1;
+#endif
+ }
+ i++;
+ }
+
+ /* Init heap information used in heap comparison algorithm */
+ xbt_mheap_t heap1 = (xbt_mheap_t)s1->read_bytes(
+ alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
+ remote(process->heap_address),
+ simgrid::mc::ProcessIndexMissing, simgrid::mc::ReadOptions::lazy());
+ xbt_mheap_t heap2 = (xbt_mheap_t)s2->read_bytes(
+ alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
+ remote(process->heap_address),
+ simgrid::mc::ProcessIndexMissing, simgrid::mc::ReadOptions::lazy());
+ res_init = simgrid::mc::init_heap_information(heap1, heap2, &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
+ }
+
+ /* Stacks comparison */
+ unsigned cursor = 0;
+ int diff_local = 0;
+#ifdef MC_DEBUG
+ is_diff = 0;
+#endif
+ mc_snapshot_stack_t stack1, stack2;
+ while (cursor < s1->stacks.size()) {
+ stack1 = &s1->stacks[cursor];
+ stack2 = &s2->stacks[cursor];
+
+ if (stack1->process_index != stack2->process_index) {
+ diff_local = 1;
+ XBT_DEBUG("(%d - %d) Stacks with different process index (%i vs %i)", num1, num2,
+ stack1->process_index, stack2->process_index);
+ }
+ else diff_local =
+ compare_local_variables(stack1->process_index, s1, s2, stack1, stack2);
+ if (diff_local > 0) {
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different local variables between stacks %d", num1,
+ num2, cursor + 1);
+ errors++;
+ is_diff = 1;
+#else
+
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different local variables between stacks %d", num1,
+ num2, cursor + 1);
+#endif
+
+ simgrid::mc::reset_heap_information();
+
+ return 1;
+#endif
+ }
+ cursor++;
+ }
+
+ size_t regions_count = s1->snapshot_regions.size();
+ // TODO, raise a difference instead?
+ xbt_assert(regions_count == s2->snapshot_regions.size());
+
+ for (size_t k = 0; k != regions_count; ++k) {
+ mc_mem_region_t region1 = s1->snapshot_regions[k].get();
+ mc_mem_region_t region2 = s2->snapshot_regions[k].get();
+
+ // Preconditions:
+ if (region1->region_type() != simgrid::mc::RegionType::Data)
+ continue;
+
+ xbt_assert(region1->region_type() == region2->region_type());
+ xbt_assert(region1->object_info() == region2->object_info());
+ xbt_assert(region1->object_info());
+
+ std::string const& name = region1->object_info()->file_name;
+
+ /* Compare global variables */
+ is_diff =
+ compare_global_variables(region1->object_info(),
+ simgrid::mc::ProcessIndexDisabled,
+ region1, region2,
+ s1, s2);
+
+ if (is_diff != 0) {
+#ifdef MC_DEBUG
+ XBT_DEBUG("(%d - %d) Different global variables in %s",
+ num1, num2, name.c_str());
+ errors++;
+#else
+#ifdef MC_VERBOSE
+ XBT_VERB("(%d - %d) Different global variables in %s",
+ num1, num2, name.c_str());
+#endif
+
+ return 1;
+#endif
+ }
+ }
+
+ /* Compare heap */
+ if (simgrid::mc::mmalloc_compare_heap(s1, s2) > 0) {
+
+#ifdef MC_DEBUG
+ 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
+
+ return 1;
+#endif
+ }
+
+ simgrid::mc::reset_heap_information();
+
+#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;
+}
+
+}
+}