1 /* Copyright (c) 2008-2022. The SimGrid Team. All rights reserved. */
3 /* This program is free software; you can redistribute it and/or modify it
4 * under the terms of the license (GNU LGPL) which comes with this package. */
6 /** \file compare.cpp Memory snapshotting and comparison */
8 #include "src/mc/mc_config.hpp"
9 #include "src/mc/mc_private.hpp"
10 #include "src/mc/sosp/Snapshot.hpp"
14 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_compare, mc, "Logging specific to mc_compare in mc");
16 namespace simgrid::mc {
18 /*********************************** Heap comparison ***********************************/
19 /***************************************************************************************/
26 HeapLocation() = default;
27 explicit HeapLocation(int block, int fragment = 0) : block_(block), fragment_(fragment) {}
29 bool operator==(HeapLocation const& that) const
31 return block_ == that.block_ && fragment_ == that.fragment_;
33 bool operator<(HeapLocation const& that) const
35 return std::make_pair(block_, fragment_) < std::make_pair(that.block_, that.fragment_);
39 using HeapLocationPair = std::array<HeapLocation, 2>;
40 using HeapLocationPairs = std::set<HeapLocationPair>;
42 class HeapArea : public HeapLocation {
46 explicit HeapArea(int block) : valid_(true) { block_ = block; }
47 HeapArea(int block, int fragment) : valid_(true)
54 class ProcessComparisonState {
56 const std::vector<IgnoredHeapRegion>* to_ignore = nullptr;
57 std::vector<HeapArea> equals_to;
58 std::vector<Type*> types;
59 std::size_t heapsize = 0;
61 void initHeapInformation(const s_xbt_mheap_t* heap, const std::vector<IgnoredHeapRegion>& i);
64 class StateComparator {
66 s_xbt_mheap_t std_heap_copy;
67 std::size_t heaplimit;
68 std::array<ProcessComparisonState, 2> processStates;
70 std::unordered_set<std::pair<const void*, const void*>, simgrid::xbt::hash<std::pair<const void*, const void*>>>
75 compared_pointers.clear();
78 int initHeapInformation(const s_xbt_mheap_t* heap1, const s_xbt_mheap_t* heap2,
79 const std::vector<IgnoredHeapRegion>& i1, const std::vector<IgnoredHeapRegion>& i2);
81 template <int rank> HeapArea& equals_to_(std::size_t i, std::size_t j)
83 return processStates[rank - 1].equals_to[MAX_FRAGMENT_PER_BLOCK * i + j];
85 template <int rank> Type*& types_(std::size_t i, std::size_t j)
87 return processStates[rank - 1].types[MAX_FRAGMENT_PER_BLOCK * i + j];
90 template <int rank> HeapArea const& equals_to_(std::size_t i, std::size_t j) const
92 return processStates[rank - 1].equals_to[MAX_FRAGMENT_PER_BLOCK * i + j];
94 template <int rank> Type* const& types_(std::size_t i, std::size_t j) const
96 return processStates[rank - 1].types[MAX_FRAGMENT_PER_BLOCK * i + j];
99 /** Check whether two blocks are known to be matching
101 * @param b1 Block of state 1
102 * @param b2 Block of state 2
103 * @return if the blocks are known to be matching
105 bool blocksEqual(int b1, int b2) const
107 return this->equals_to_<1>(b1, 0).block_ == b2 && this->equals_to_<2>(b2, 0).block_ == b1;
110 /** Check whether two fragments are known to be matching
112 * @param b1 Block of state 1
113 * @param f1 Fragment of state 1
114 * @param b2 Block of state 2
115 * @param f2 Fragment of state 2
116 * @return if the fragments are known to be matching
118 int fragmentsEqual(int b1, int f1, int b2, int f2) const
120 return this->equals_to_<1>(b1, f1).block_ == b2 && this->equals_to_<1>(b1, f1).fragment_ == f2 &&
121 this->equals_to_<2>(b2, f2).block_ == b1 && this->equals_to_<2>(b2, f2).fragment_ == f1;
124 void match_equals(const HeapLocationPairs* list);
127 } // namespace simgrid::mc
129 /************************************************************************************/
131 static ssize_t heap_comparison_ignore_size(const std::vector<simgrid::mc::IgnoredHeapRegion>* ignore_list,
134 auto pos = std::lower_bound(ignore_list->begin(), ignore_list->end(), address,
135 [](auto const& reg, auto const* addr) { return reg.address < addr; });
136 return (pos != ignore_list->end() && pos->address == address) ? pos->size : -1;
139 static bool is_stack(const simgrid::mc::RemoteProcess& process, const void* address)
141 auto const& stack_areas = process.stack_areas();
142 return std::any_of(stack_areas.begin(), stack_areas.end(),
143 [address](auto const& stack) { return stack.address == address; });
146 // TODO, this should depend on the snapshot?
147 static bool is_block_stack(const simgrid::mc::RemoteProcess& process, int block)
149 auto const& stack_areas = process.stack_areas();
150 return std::any_of(stack_areas.begin(), stack_areas.end(),
151 [block](auto const& stack) { return stack.block == block; });
154 namespace simgrid::mc {
156 void StateComparator::match_equals(const HeapLocationPairs* list)
158 for (auto const& pair : *list) {
159 if (pair[0].fragment_ != -1) {
160 this->equals_to_<1>(pair[0].block_, pair[0].fragment_) = HeapArea(pair[1].block_, pair[1].fragment_);
161 this->equals_to_<2>(pair[1].block_, pair[1].fragment_) = HeapArea(pair[0].block_, pair[0].fragment_);
163 this->equals_to_<1>(pair[0].block_, 0) = HeapArea(pair[1].block_, pair[1].fragment_);
164 this->equals_to_<2>(pair[1].block_, 0) = HeapArea(pair[0].block_, pair[0].fragment_);
169 void ProcessComparisonState::initHeapInformation(const s_xbt_mheap_t* heap, const std::vector<IgnoredHeapRegion>& i)
171 auto heaplimit = heap->heaplimit;
172 this->heapsize = heap->heapsize;
173 this->to_ignore = &i;
174 this->equals_to.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, HeapArea());
175 this->types.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, nullptr);
178 int StateComparator::initHeapInformation(const s_xbt_mheap_t* heap1, const s_xbt_mheap_t* heap2,
179 const std::vector<IgnoredHeapRegion>& i1,
180 const std::vector<IgnoredHeapRegion>& i2)
182 if ((heap1->heaplimit != heap2->heaplimit) || (heap1->heapsize != heap2->heapsize))
184 this->heaplimit = heap1->heaplimit;
185 this->std_heap_copy = *mc_model_checker->get_remote_process().get_heap();
186 this->processStates[0].initHeapInformation(heap1, i1);
187 this->processStates[1].initHeapInformation(heap2, i2);
191 // TODO, have a robust way to find it in O(1)
192 static inline Region* MC_get_heap_region(const Snapshot& snapshot)
194 for (auto const& region : snapshot.snapshot_regions_)
195 if (region->region_type() == RegionType::Heap)
197 xbt_die("No heap region");
200 static bool heap_area_differ(const RemoteProcess& process, StateComparator& state, const void* area1, const void* area2,
201 const Snapshot& snapshot1, const Snapshot& snapshot2, HeapLocationPairs* previous,
202 Type* type, int pointer_level);
204 /* Compares the content of each heap fragment between the two states, at the bit level.
206 * This operation is costly (about 5 seconds per snapshots' pair to compare on a small program),
207 * but hard to optimize because our algorithm is too hackish.
209 * Going at bit level can trigger syntaxtic differences on states that are semantically equivalent.
211 * Padding bytes constitute the first source of such syntaxtic difference: Any malloced memory contains spaces that
212 * are not used to enforce the memory alignment constraints of the CPU. So, cruft of irrelevant changes could get
213 * added on these bits. But this case is handled properly, as any memory block is zeroed by mmalloc before being handled
214 * back, not only for calloc but also for malloc. So the memory interstices due to padding bytes are properly zeroed.
216 * Another source of such change comes from the order of mallocs, that may well change from one execution path to
217 * another. This will change the malloc fragment in which the data is stored and the pointer values (syntaxtic
218 * difference) while the semantic of the state remains the same.
220 * To fix this, this code relies on a hugly hack. When we see a difference during the bit-level comparison,
221 * we first check if it could be explained by a pointer-to-block difference. Ie, if when interpreting the memory
222 * area containing that difference as a pointer, I get the pointer to a valid fragment in the heap (in both snapshots).
224 * This is why we cannot pre-compute a bit-level hash of the heap content: we discover the pointers to other memory
225 * fragment when a difference is found during the bit-level exploration. Fixing this would require to save typing
226 * information about the memory fragments, which is something that could be done with https://github.com/tudasc/TypeART
227 * This would give us all pointers in the mallocated memory, allowing the graph traversal needed to precompute the hash.
229 * Using a hash without paying attention to malloc fragment reordering would lead to false negatives:
230 * semantically equivalent states would be detected as [syntaxically] different. It's of no importance for the
231 * state-equality reduction (we would re-explore semantically equivalent states), but it would endanger the soundness
232 * of the liveness model-checker, as state-equality is used to detect the loops that constitute the accepting states of
233 * the verified property. So we could miss counter-examples to the verified property. Not good. Not good at all.
235 static bool mmalloc_heap_differ(const RemoteProcess& process, StateComparator& state, const Snapshot& snapshot1,
236 const Snapshot& snapshot2)
238 /* Check busy blocks */
241 malloc_info heapinfo_temp1;
242 malloc_info heapinfo_temp2;
243 malloc_info heapinfo_temp2b;
245 const Region* heap_region1 = MC_get_heap_region(snapshot1);
246 const Region* heap_region2 = MC_get_heap_region(snapshot2);
248 // This is the address of std_heap->heapinfo in the application process:
249 uint64_t heapinfo_address = process.heap_address.address() + offsetof(s_xbt_mheap_t, heapinfo);
251 // This is in snapshot do not use them directly:
252 const malloc_info* heapinfos1 = snapshot1.read(remote<malloc_info*>(heapinfo_address));
253 const malloc_info* heapinfos2 = snapshot2.read(remote<malloc_info*>(heapinfo_address));
255 while (i1 < state.heaplimit) {
256 const auto* heapinfo1 =
257 static_cast<malloc_info*>(heap_region1->read(&heapinfo_temp1, &heapinfos1[i1], sizeof(malloc_info)));
258 const auto* heapinfo2 =
259 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2, &heapinfos2[i1], sizeof(malloc_info)));
261 if (heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type == MMALLOC_TYPE_HEAPINFO) { /* Free block */
266 xbt_assert(heapinfo1->type >= 0, "Unknown mmalloc block type: %d", heapinfo1->type);
268 void* addr_block1 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
270 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
271 if (is_stack(process, addr_block1)) {
272 for (size_t k = 0; k < heapinfo1->busy_block.size; k++)
273 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
274 for (size_t k = 0; k < heapinfo2->busy_block.size; k++)
275 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
276 i1 += heapinfo1->busy_block.size;
280 if (state.equals_to_<1>(i1, 0).valid_) {
288 /* Try first to associate to same block in the other heap */
289 if (heapinfo2->type == heapinfo1->type && state.equals_to_<2>(i1, 0).valid_ == 0) {
290 const void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
291 if (not heap_area_differ(process, state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
292 for (size_t k = 1; k < heapinfo2->busy_block.size; k++)
293 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
294 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
295 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
297 i1 += heapinfo1->busy_block.size;
301 while (i2 < state.heaplimit && not equal) {
302 const void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
309 const auto* heapinfo2b =
310 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info)));
312 if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
317 if (state.equals_to_<2>(i2, 0).valid_) {
322 if (not heap_area_differ(process, state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
323 for (size_t k = 1; k < heapinfo2b->busy_block.size; k++)
324 state.equals_to_<2>(i2 + k, 0) = HeapArea(i1, -1);
325 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
326 state.equals_to_<1>(i1 + k, 0) = HeapArea(i2, -1);
328 i1 += heapinfo1->busy_block.size;
334 XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
337 } else { /* Fragmented block */
338 for (size_t j1 = 0; j1 < (size_t)(BLOCKSIZE >> heapinfo1->type); j1++) {
339 if (heapinfo1->busy_frag.frag_size[j1] == -1) /* Free fragment_ */
342 if (state.equals_to_<1>(i1, j1).valid_)
345 void* addr_frag1 = (char*)addr_block1 + (j1 << heapinfo1->type);
350 /* Try first to associate to same fragment_ in the other heap */
351 if (heapinfo2->type == heapinfo1->type && not state.equals_to_<2>(i1, j1).valid_) {
352 const void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
353 const void* addr_frag2 = (const char*)addr_block2 + (j1 << heapinfo2->type);
354 if (not heap_area_differ(process, state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0))
358 while (i2 < state.heaplimit && not equal) {
359 const auto* heapinfo2b =
360 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info)));
362 if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
367 // We currently do not match fragments with unfragmented blocks (maybe we should).
368 if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
373 xbt_assert(heapinfo2b->type >= 0, "Unknown mmalloc block type: %d", heapinfo2b->type);
375 for (size_t j2 = 0; j2 < (size_t)(BLOCKSIZE >> heapinfo2b->type); j2++) {
376 if (i2 == i1 && j2 == j1)
379 if (state.equals_to_<2>(i2, j2).valid_)
382 const void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
383 const void* addr_frag2 = (const char*)addr_block2 + (j2 << heapinfo2b->type);
385 if (not heap_area_differ(process, state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr,
395 XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
396 heapinfo1->busy_frag.frag_size[j1], addr_frag1);
404 /* All blocks/fragments are equal to another block/fragment_ ? */
405 for (size_t i = 1; i < state.heaplimit; i++) {
406 const auto* heapinfo1 =
407 static_cast<malloc_info*>(heap_region1->read(&heapinfo_temp1, &heapinfos1[i], sizeof(malloc_info)));
409 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo1->busy_block.busy_size > 0 &&
410 not state.equals_to_<1>(i, 0).valid_) {
411 XBT_DEBUG("Block %zu not found (size used = %zu)", i, heapinfo1->busy_block.busy_size);
415 if (heapinfo1->type <= 0)
417 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo1->type); j++)
418 if (i1 == state.heaplimit && heapinfo1->busy_frag.frag_size[j] > 0 && not state.equals_to_<1>(i, j).valid_) {
419 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)", i, j, heapinfo1->busy_frag.frag_size[j]);
424 for (size_t i = 1; i < state.heaplimit; i++) {
425 const auto* heapinfo2 =
426 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2, &heapinfos2[i], sizeof(malloc_info)));
427 if (heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo2->busy_block.busy_size > 0 &&
428 not state.equals_to_<2>(i, 0).valid_) {
429 XBT_DEBUG("Block %zu not found (size used = %zu)", i,
430 heapinfo2->busy_block.busy_size);
434 if (heapinfo2->type <= 0)
437 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo2->type); j++)
438 if (i1 == state.heaplimit && heapinfo2->busy_frag.frag_size[j] > 0 && not state.equals_to_<2>(i, j).valid_) {
439 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)",
440 i, j, heapinfo2->busy_frag.frag_size[j]);
450 * @param real_area1 Process address for state 1
451 * @param real_area2 Process address for state 2
452 * @param snapshot1 Snapshot of state 1
453 * @param snapshot2 Snapshot of state 2
456 * @param check_ignore
457 * @return true when different, false otherwise (same or unknown)
459 static bool heap_area_differ_without_type(const RemoteProcess& process, StateComparator& state, const void* real_area1,
460 const void* real_area2, const Snapshot& snapshot1, const Snapshot& snapshot2,
461 HeapLocationPairs* previous, int size, int check_ignore)
463 const Region* heap_region1 = MC_get_heap_region(snapshot1);
464 const Region* heap_region2 = MC_get_heap_region(snapshot2);
466 for (int i = 0; i < size; ) {
467 if (check_ignore > 0) {
468 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, (const char*)real_area1 + i);
470 ssize_t ignore2 = heap_comparison_ignore_size(state.processStates[1].to_ignore, (const char*)real_area2 + i);
471 if (ignore2 == ignore1) {
483 if (MC_snapshot_region_memcmp((const char*)real_area1 + i, heap_region1, (const char*)real_area2 + i, heap_region2,
485 int pointer_align = (i / sizeof(void *)) * sizeof(void *);
486 const void* addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + pointer_align)));
487 const void* addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + pointer_align)));
489 if (process.in_maestro_stack(remote(addr_pointed1)) && process.in_maestro_stack(remote(addr_pointed2))) {
490 i = pointer_align + sizeof(void *);
494 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)) {
495 // Both addresses are in the heap:
496 if (heap_area_differ(process, state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, nullptr, 0))
498 i = pointer_align + sizeof(void *);
511 * @param real_area1 Process address for state 1
512 * @param real_area2 Process address for state 2
513 * @param snapshot1 Snapshot of state 1
514 * @param snapshot2 Snapshot of state 2
517 * @param area_size either a byte_size or an elements_count (?)
518 * @param check_ignore
519 * @param pointer_level
520 * @return true when different, false otherwise (same or unknown)
522 static bool heap_area_differ_with_type(const simgrid::mc::RemoteProcess& process, StateComparator& state,
523 const void* real_area1, const void* real_area2, const Snapshot& snapshot1,
524 const Snapshot& snapshot2, HeapLocationPairs* previous, const Type* type,
525 int area_size, int check_ignore, int pointer_level)
527 // HACK: This should not happen but in practice, there are some
528 // DW_TAG_typedef without an associated DW_AT_type:
529 //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
530 // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
531 // <538837> DW_AT_decl_file : 98
532 // <538838> DW_AT_decl_line : 37
536 if (is_stack(process, real_area1) && is_stack(process, real_area2))
539 if (check_ignore > 0) {
540 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
541 if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
546 const Type* subsubtype;
548 const void* addr_pointed1;
549 const void* addr_pointed2;
551 const Region* heap_region1 = MC_get_heap_region(snapshot1);
552 const Region* heap_region2 = MC_get_heap_region(snapshot2);
554 switch (type->type) {
555 case DW_TAG_unspecified_type:
558 case DW_TAG_base_type:
559 if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
560 if (real_area1 == real_area2)
563 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
565 if (area_size != -1 && type->byte_size != area_size)
568 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
571 case DW_TAG_enumeration_type:
572 if (area_size != -1 && type->byte_size != area_size)
574 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
577 case DW_TAG_const_type:
578 case DW_TAG_volatile_type:
579 return heap_area_differ_with_type(process, state, real_area1, real_area2, snapshot1, snapshot2, previous,
580 type->subtype, area_size, check_ignore, pointer_level);
582 case DW_TAG_array_type:
583 subtype = type->subtype;
584 switch (subtype->type) {
585 case DW_TAG_unspecified_type:
588 case DW_TAG_base_type:
589 case DW_TAG_enumeration_type:
590 case DW_TAG_pointer_type:
591 case DW_TAG_reference_type:
592 case DW_TAG_rvalue_reference_type:
593 case DW_TAG_structure_type:
594 case DW_TAG_class_type:
595 case DW_TAG_union_type:
596 if (subtype->full_type)
597 subtype = subtype->full_type;
598 elm_size = subtype->byte_size;
600 // TODO, just remove the type indirection?
601 case DW_TAG_const_type:
603 case DW_TAG_volatile_type:
604 subsubtype = subtype->subtype;
605 if (subsubtype->full_type)
606 subsubtype = subsubtype->full_type;
607 elm_size = subsubtype->byte_size;
612 for (int i = 0; i < type->element_count; i++) {
613 // TODO, add support for variable stride (DW_AT_byte_stride)
614 if (heap_area_differ_with_type(process, state, (const char*)real_area1 + (i * elm_size),
615 (const char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
616 type->subtype, subtype->byte_size, check_ignore, pointer_level))
621 case DW_TAG_reference_type:
622 case DW_TAG_rvalue_reference_type:
623 case DW_TAG_pointer_type:
624 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
625 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
626 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
627 return (addr_pointed1 != addr_pointed2);
630 if (pointer_level <= 1) {
631 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
632 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
633 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2))
634 return heap_area_differ(process, state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
635 type->subtype, pointer_level);
637 return (addr_pointed1 != addr_pointed2);
639 for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
640 addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + i * sizeof(void*))));
641 addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + i * sizeof(void*))));
642 bool differ = snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)
643 ? heap_area_differ(process, state, addr_pointed1, addr_pointed2, snapshot1, snapshot2,
644 previous, type->subtype, pointer_level)
645 : addr_pointed1 != addr_pointed2;
651 case DW_TAG_structure_type:
652 case DW_TAG_class_type:
654 type = type->full_type;
655 if (type->byte_size == 0)
657 if (area_size != -1 && type->byte_size != area_size) {
658 if (area_size <= type->byte_size || area_size % type->byte_size != 0)
660 for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
661 if (heap_area_differ_with_type(process, state, (const char*)real_area1 + i * type->byte_size,
662 (const char*)real_area2 + i * type->byte_size, snapshot1, snapshot2, previous,
663 type, -1, check_ignore, 0))
667 for (const simgrid::mc::Member& member : type->members) {
668 // TODO, optimize this? (for the offset case)
669 const void* real_member1 = dwarf::resolve_member(real_area1, type, &member, &snapshot1);
670 const void* real_member2 = dwarf::resolve_member(real_area2, type, &member, &snapshot2);
671 if (heap_area_differ_with_type(process, state, real_member1, real_member2, snapshot1, snapshot2, previous,
672 member.type, -1, check_ignore, 0))
678 case DW_TAG_union_type:
679 return heap_area_differ_without_type(process, state, real_area1, real_area2, snapshot1, snapshot2, previous,
680 type->byte_size, check_ignore);
687 /** Infer the type of a part of the block from the type of the block
689 * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
691 * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
693 * @param type DWARF type ID of the root address
695 * @return DWARF type ID for given offset
697 static Type* get_offset_type(void* real_base_address, Type* type, int offset, int area_size, const Snapshot& snapshot)
699 // Beginning of the block, the inferred variable type if the type of the block:
703 switch (type->type) {
704 case DW_TAG_structure_type:
705 case DW_TAG_class_type:
707 type = type->full_type;
708 if (area_size != -1 && type->byte_size != area_size) {
709 if (area_size > type->byte_size && area_size % type->byte_size == 0)
715 for (const simgrid::mc::Member& member : type->members) {
716 if (member.has_offset_location()) {
717 // We have the offset, use it directly (shortcut):
718 if (member.offset() == offset)
721 void* real_member = dwarf::resolve_member(real_base_address, type, &member, &snapshot);
722 if ((char*)real_member - (char*)real_base_address == offset)
729 /* FIXME: other cases ? */
736 * @param area1 Process address for state 1
737 * @param area2 Process address for state 2
738 * @param snapshot1 Snapshot of state 1
739 * @param snapshot2 Snapshot of state 2
740 * @param previous Pairs of blocks already compared on the current path (or nullptr)
741 * @param type_id Type of variable
742 * @param pointer_level
743 * @return true when different, false otherwise (same or unknown)
745 static bool heap_area_differ(const RemoteProcess& process, StateComparator& state, const void* area1, const void* area2,
746 const Snapshot& snapshot1, const Snapshot& snapshot2, HeapLocationPairs* previous,
747 Type* type, int pointer_level)
752 int check_ignore = 0;
760 Type* new_type1 = nullptr;
762 bool match_pairs = false;
764 // This is the address of std_heap->heapinfo in the application process:
765 uint64_t heapinfo_address = process.heap_address.address() + offsetof(s_xbt_mheap_t, heapinfo);
767 const malloc_info* heapinfos1 = snapshot1.read(remote<malloc_info*>(heapinfo_address));
768 const malloc_info* heapinfos2 = snapshot2.read(remote<malloc_info*>(heapinfo_address));
770 malloc_info heapinfo_temp1;
771 malloc_info heapinfo_temp2;
773 simgrid::mc::HeapLocationPairs current;
774 if (previous == nullptr) {
780 block1 = ((const char*)area1 - (const char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
781 block2 = ((const char*)area2 - (const char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
783 // If either block is a stack block:
784 if (is_block_stack(process, (int)block1) && is_block_stack(process, (int)block2)) {
785 previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}});
787 state.match_equals(previous);
791 // If either block is not in the expected area of memory:
792 if (((const char*)area1 < (const char*)state.std_heap_copy.heapbase) ||
793 (block1 > (ssize_t)state.processStates[0].heapsize) || (block1 < 1) ||
794 ((const char*)area2 < (const char*)state.std_heap_copy.heapbase) ||
795 (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
799 // Process address of the block:
800 void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
801 void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
805 type = type->full_type;
807 // This assume that for "boring" types (volatile ...) byte_size is absent:
808 while (type->byte_size == 0 && type->subtype != nullptr)
809 type = type->subtype;
812 if (type->type == DW_TAG_pointer_type ||
813 (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
816 type_size = type->byte_size;
819 const Region* heap_region1 = MC_get_heap_region(snapshot1);
820 const Region* heap_region2 = MC_get_heap_region(snapshot2);
822 const auto* heapinfo1 =
823 static_cast<malloc_info*>(heap_region1->read(&heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info)));
824 const auto* heapinfo2 =
825 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info)));
827 if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
828 && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
831 state.match_equals(previous);
835 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
838 // TODO, lookup variable type from block type as done for fragmented blocks
840 if (state.equals_to_<1>(block1, 0).valid_ && state.equals_to_<2>(block2, 0).valid_ &&
841 state.blocksEqual(block1, block2)) {
843 state.match_equals(previous);
847 if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
848 type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
849 (type->name.empty() ||
850 type->name == "struct s_smx_context")) { // FIXME: there is no struct s_smx_context anymore
852 state.match_equals(previous);
856 if (heapinfo1->busy_block.size != heapinfo2->busy_block.size ||
857 heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
860 if (not previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}}).second) {
862 state.match_equals(previous);
866 size = heapinfo1->busy_block.busy_size;
868 // Remember (basic) type inference.
869 // The current data structure only allows us to do this for the whole block.
870 if (type != nullptr && area1 == real_addr_block1)
871 state.types_<1>(block1, 0) = type;
872 if (type != nullptr && area2 == real_addr_block2)
873 state.types_<2>(block2, 0) = type;
877 state.match_equals(previous);
881 if (heapinfo1->busy_block.ignore > 0 && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
882 check_ignore = heapinfo1->busy_block.ignore;
884 } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
886 ssize_t frag1 = (ADDR2UINT(area1) % BLOCKSIZE) >> heapinfo1->type;
887 ssize_t frag2 = (ADDR2UINT(area2) % BLOCKSIZE) >> heapinfo2->type;
889 // Process address of the fragment_:
890 void* real_addr_frag1 = (char*)real_addr_block1 + (frag1 << heapinfo1->type);
891 void* real_addr_frag2 = (char*)real_addr_block2 + (frag2 << heapinfo2->type);
893 // Check the size of the fragments against the size of the type:
894 if (type_size != -1) {
895 if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
897 state.match_equals(previous);
901 if (type_size != heapinfo1->busy_frag.frag_size[frag1]
902 || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
904 state.match_equals(previous);
909 // Check if the blocks are already matched together:
910 if (state.equals_to_<1>(block1, frag1).valid_ && state.equals_to_<2>(block2, frag2).valid_ &&
911 state.fragmentsEqual(block1, frag1, block2, frag2)) {
913 state.match_equals(previous);
916 // Compare the size of both fragments:
917 if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
918 if (type_size == -1) {
920 state.match_equals(previous);
926 // Size of the fragment_:
927 size = heapinfo1->busy_frag.frag_size[frag1];
929 // Remember (basic) type inference.
930 // The current data structure only allows us to do this for the whole fragment_.
931 if (type != nullptr && area1 == real_addr_frag1)
932 state.types_<1>(block1, frag1) = type;
933 if (type != nullptr && area2 == real_addr_frag2)
934 state.types_<2>(block2, frag2) = type;
936 // The type of the variable is already known:
940 // Type inference from the block type.
941 else if (state.types_<1>(block1, frag1) != nullptr || state.types_<2>(block2, frag2) != nullptr) {
942 Type* new_type2 = nullptr;
944 offset1 = (const char*)area1 - (const char*)real_addr_frag1;
945 offset2 = (const char*)area2 - (const char*)real_addr_frag2;
947 if (state.types_<1>(block1, frag1) != nullptr && state.types_<2>(block2, frag2) != nullptr) {
948 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
949 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset1, size, snapshot2);
950 } else if (state.types_<1>(block1, frag1) != nullptr) {
951 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
952 new_type2 = get_offset_type(real_addr_frag2, state.types_<1>(block1, frag1), offset2, size, snapshot2);
953 } else if (state.types_<2>(block2, frag2) != nullptr) {
954 new_type1 = get_offset_type(real_addr_frag1, state.types_<2>(block2, frag2), offset1, size, snapshot1);
955 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset2, size, snapshot2);
958 state.match_equals(previous);
962 if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
964 while (type->byte_size == 0 && type->subtype != nullptr)
965 type = type->subtype;
966 new_size1 = type->byte_size;
969 while (type->byte_size == 0 && type->subtype != nullptr)
970 type = type->subtype;
971 new_size2 = type->byte_size;
975 state.match_equals(previous);
980 if (new_size1 > 0 && new_size1 == new_size2) {
985 if (offset1 == 0 && offset2 == 0 &&
986 not previous->insert(HeapLocationPair{{HeapLocation(block1, frag1), HeapLocation(block2, frag2)}}).second) {
988 state.match_equals(previous);
994 state.match_equals(previous);
998 if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
999 (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
1000 check_ignore = heapinfo1->busy_frag.ignore[frag1];
1004 /* Start comparison */
1005 if (type ? heap_area_differ_with_type(process, state, area1, area2, snapshot1, snapshot2, previous, type, size,
1006 check_ignore, pointer_level)
1007 : heap_area_differ_without_type(process, state, area1, area2, snapshot1, snapshot2, previous, size,
1012 state.match_equals(previous);
1015 } // namespace simgrid::mc
1017 /************************** Snapshot comparison *******************************/
1018 /******************************************************************************/
1020 static bool areas_differ_with_type(const simgrid::mc::RemoteProcess& process, simgrid::mc::StateComparator& state,
1021 const void* real_area1, const simgrid::mc::Snapshot& snapshot1,
1022 simgrid::mc::Region* region1, const void* real_area2,
1023 const simgrid::mc::Snapshot& snapshot2, simgrid::mc::Region* region2,
1024 const simgrid::mc::Type* type, int pointer_level)
1026 const simgrid::mc::Type* subtype;
1027 const simgrid::mc::Type* subsubtype;
1030 xbt_assert(type != nullptr);
1031 switch (type->type) {
1032 case DW_TAG_unspecified_type:
1035 case DW_TAG_base_type:
1036 case DW_TAG_enumeration_type:
1037 case DW_TAG_union_type:
1038 return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
1039 case DW_TAG_typedef:
1040 case DW_TAG_volatile_type:
1041 case DW_TAG_const_type:
1042 return areas_differ_with_type(process, state, real_area1, snapshot1, region1, real_area2, snapshot2, region2,
1043 type->subtype, pointer_level);
1044 case DW_TAG_array_type:
1045 subtype = type->subtype;
1046 switch (subtype->type) {
1047 case DW_TAG_unspecified_type:
1050 case DW_TAG_base_type:
1051 case DW_TAG_enumeration_type:
1052 case DW_TAG_pointer_type:
1053 case DW_TAG_reference_type:
1054 case DW_TAG_rvalue_reference_type:
1055 case DW_TAG_structure_type:
1056 case DW_TAG_class_type:
1057 case DW_TAG_union_type:
1058 if (subtype->full_type)
1059 subtype = subtype->full_type;
1060 elm_size = subtype->byte_size;
1062 case DW_TAG_const_type:
1063 case DW_TAG_typedef:
1064 case DW_TAG_volatile_type:
1065 subsubtype = subtype->subtype;
1066 if (subsubtype->full_type)
1067 subsubtype = subsubtype->full_type;
1068 elm_size = subsubtype->byte_size;
1073 for (int i = 0; i < type->element_count; i++) {
1074 size_t off = i * elm_size;
1075 if (areas_differ_with_type(process, state, (const char*)real_area1 + off, snapshot1, region1,
1076 (const char*)real_area2 + off, snapshot2, region2, type->subtype, pointer_level))
1080 case DW_TAG_pointer_type:
1081 case DW_TAG_reference_type:
1082 case DW_TAG_rvalue_reference_type: {
1083 const void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
1084 const void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
1086 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
1087 return (addr_pointed1 != addr_pointed2);
1088 if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
1090 if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
1092 if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
1097 // Some cases are not handled here:
1098 // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
1099 // * a pointer leads to the read-only segment of the current object
1100 // * a pointer lead to a different ELF object
1102 if (snapshot1.on_heap(addr_pointed1)) {
1103 if (not snapshot2.on_heap(addr_pointed2))
1105 // The pointers are both in the heap:
1106 return simgrid::mc::heap_area_differ(process, state, addr_pointed1, addr_pointed2, snapshot1, snapshot2,
1107 nullptr, type->subtype, pointer_level);
1109 } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
1110 // The pointers are both in the current object R/W segment:
1111 if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
1113 if (not type->type_id)
1114 return (addr_pointed1 != addr_pointed2);
1116 return areas_differ_with_type(process, state, addr_pointed1, snapshot1, region1, addr_pointed2, snapshot2,
1117 region2, type->subtype, pointer_level);
1119 // TODO, We do not handle very well the case where
1120 // it belongs to a different (non-heap) region from the current one.
1122 return (addr_pointed1 != addr_pointed2);
1125 case DW_TAG_structure_type:
1126 case DW_TAG_class_type:
1127 for (const simgrid::mc::Member& member : type->members) {
1128 const void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
1129 const void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
1130 simgrid::mc::Region* subregion1 = snapshot1.get_region(member1, region1); // region1 is hinted
1131 simgrid::mc::Region* subregion2 = snapshot2.get_region(member2, region2); // region2 is hinted
1132 if (areas_differ_with_type(process, state, member1, snapshot1, subregion1, member2, snapshot2, subregion2,
1133 member.type, pointer_level))
1137 case DW_TAG_subroutine_type:
1140 XBT_VERB("Unknown case: %d", type->type);
1147 static bool global_variables_differ(const simgrid::mc::RemoteProcess& process, simgrid::mc::StateComparator& state,
1148 const simgrid::mc::ObjectInformation* object_info, simgrid::mc::Region* r1,
1149 simgrid::mc::Region* r2, const simgrid::mc::Snapshot& snapshot1,
1150 const simgrid::mc::Snapshot& snapshot2)
1152 xbt_assert(r1 && r2, "Missing region.");
1154 const std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
1156 for (simgrid::mc::Variable const& current_var : variables) {
1157 // If the variable is not in this object, skip it:
1158 // We do not expect to find a pointer to something which is not reachable
1159 // by the global variables.
1160 if ((char*)current_var.address < object_info->start_rw || (char*)current_var.address > object_info->end_rw)
1163 const simgrid::mc::Type* bvariable_type = current_var.type;
1164 if (areas_differ_with_type(process, state, current_var.address, snapshot1, r1, current_var.address, snapshot2, r2,
1165 bvariable_type, 0)) {
1166 XBT_VERB("Global variable %s (%p) is different between snapshots", current_var.name.c_str(), current_var.address);
1174 static bool local_variables_differ(const simgrid::mc::RemoteProcess& process, simgrid::mc::StateComparator& state,
1175 const simgrid::mc::Snapshot& snapshot1, const simgrid::mc::Snapshot& snapshot2,
1176 const_mc_snapshot_stack_t stack1, const_mc_snapshot_stack_t stack2)
1178 if (stack1->local_variables.size() != stack2->local_variables.size()) {
1179 XBT_VERB("Different number of local variables");
1183 for (unsigned int cursor = 0; cursor < stack1->local_variables.size(); cursor++) {
1184 const_local_variable_t current_var1 = &stack1->local_variables[cursor];
1185 const_local_variable_t current_var2 = &stack2->local_variables[cursor];
1186 if (current_var1->name != current_var2->name || current_var1->subprogram != current_var2->subprogram ||
1187 current_var1->ip != current_var2->ip) {
1188 // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
1189 XBT_VERB("Different name of variable (%s - %s) or frame (%s - %s) or ip (%lu - %lu)", current_var1->name.c_str(),
1190 current_var2->name.c_str(), current_var1->subprogram->name.c_str(),
1191 current_var2->subprogram->name.c_str(), current_var1->ip, current_var2->ip);
1195 if (areas_differ_with_type(process, state, current_var1->address, snapshot1,
1196 snapshot1.get_region(current_var1->address), current_var2->address, snapshot2,
1197 snapshot2.get_region(current_var2->address), current_var1->type, 0)) {
1198 XBT_VERB("Local variable %s (%p - %p) in frame %s is different between snapshots", current_var1->name.c_str(),
1199 current_var1->address, current_var2->address, current_var1->subprogram->name.c_str());
1206 namespace simgrid::mc {
1208 bool Snapshot::operator==(const Snapshot& other)
1210 // TODO, make this a field of ModelChecker or something similar
1211 static StateComparator state_comparator;
1213 const RemoteProcess& process = mc_model_checker->get_remote_process();
1215 if (hash_ != other.hash_) {
1216 XBT_VERB("(%ld - %ld) Different hash: 0x%" PRIx64 "--0x%" PRIx64, this->num_state_, other.num_state_, this->hash_,
1220 XBT_VERB("(%ld - %ld) Same hash: 0x%" PRIx64, this->num_state_, other.num_state_, this->hash_);
1222 /* TODO: re-enable the quick filter of counting enabled processes in each snapshots */
1224 /* Compare size of stacks */
1225 for (unsigned long i = 0; i < this->stacks_.size(); i++) {
1226 size_t size_used1 = this->stack_sizes_[i];
1227 size_t size_used2 = other.stack_sizes_[i];
1228 if (size_used1 != size_used2) {
1229 XBT_VERB("(%ld - %ld) Different size used in stacks: %zu - %zu", num_state_, other.num_state_, size_used1,
1235 /* Init heap information used in heap comparison algorithm */
1236 const s_xbt_mheap_t* heap1 = static_cast<xbt_mheap_t>(this->read_bytes(
1237 alloca(sizeof(s_xbt_mheap_t)), sizeof(s_xbt_mheap_t), process.heap_address, ReadOptions::lazy()));
1238 const s_xbt_mheap_t* heap2 = static_cast<xbt_mheap_t>(other.read_bytes(
1239 alloca(sizeof(s_xbt_mheap_t)), sizeof(s_xbt_mheap_t), process.heap_address, ReadOptions::lazy()));
1240 if (state_comparator.initHeapInformation(heap1, heap2, this->to_ignore_, other.to_ignore_) == -1) {
1241 XBT_VERB("(%ld - %ld) Different heap information", this->num_state_, other.num_state_);
1245 /* Stacks comparison */
1246 for (unsigned int cursor = 0; cursor < this->stacks_.size(); cursor++) {
1247 const_mc_snapshot_stack_t stack1 = &this->stacks_[cursor];
1248 const_mc_snapshot_stack_t stack2 = &other.stacks_[cursor];
1250 if (local_variables_differ(process, state_comparator, *this, other, stack1, stack2)) {
1251 XBT_VERB("(%ld - %ld) Different local variables between stacks %u", this->num_state_, other.num_state_,
1257 size_t regions_count = this->snapshot_regions_.size();
1258 if (regions_count != other.snapshot_regions_.size())
1261 for (size_t k = 0; k != regions_count; ++k) {
1262 Region* region1 = this->snapshot_regions_[k].get();
1263 Region* region2 = other.snapshot_regions_[k].get();
1266 if (region1->region_type() != RegionType::Data)
1269 xbt_assert(region1->region_type() == region2->region_type());
1270 xbt_assert(region1->object_info() == region2->object_info());
1271 xbt_assert(region1->object_info());
1273 /* Compare global variables */
1274 if (global_variables_differ(process, state_comparator, region1->object_info(), region1, region2, *this, other)) {
1275 std::string const& name = region1->object_info()->file_name;
1276 XBT_VERB("(%ld - %ld) Different global variables in %s", this->num_state_, other.num_state_, name.c_str());
1281 XBT_VERB(" Compare heap...");
1283 if (mmalloc_heap_differ(process, state_comparator, *this, other)) {
1284 XBT_VERB("(%ld - %ld) Different heap (mmalloc_heap_differ)", this->num_state_, other.num_state_);
1288 XBT_VERB("(%ld - %ld) No difference found", this->num_state_, other.num_state_);
1292 } // namespace simgrid::mc