1 /* Copyright (c) 2008-2019. 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/mc_smx.hpp"
11 #include "src/mc/sosp/Snapshot.hpp"
13 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_compare, xbt, "Logging specific to mc_compare in mc");
15 using simgrid::mc::remote;
20 /*********************************** Heap comparison ***********************************/
21 /***************************************************************************************/
28 HeapLocation() = default;
29 HeapLocation(int block, int fragment = 0) : block_(block), fragment_(fragment) {}
31 bool operator==(HeapLocation const& that) const
33 return block_ == that.block_ && fragment_ == that.fragment_;
35 bool operator<(HeapLocation const& that) const
37 return std::make_pair(block_, fragment_) < std::make_pair(that.block_, that.fragment_);
41 typedef std::array<HeapLocation, 2> HeapLocationPair;
42 typedef std::set<HeapLocationPair> HeapLocationPairs;
44 class HeapArea : public HeapLocation {
48 explicit HeapArea(int block) : valid_(true) { block_ = block; }
49 HeapArea(int block, int fragment) : valid_(true)
56 class ProcessComparisonState {
58 const std::vector<simgrid::mc::IgnoredHeapRegion>* to_ignore = nullptr;
59 std::vector<HeapArea> equals_to;
60 std::vector<simgrid::mc::Type*> types;
61 std::size_t heapsize = 0;
63 void initHeapInformation(xbt_mheap_t heap, const std::vector<simgrid::mc::IgnoredHeapRegion>& i);
66 class StateComparator {
68 s_xbt_mheap_t std_heap_copy;
69 std::size_t heaplimit;
70 std::array<ProcessComparisonState, 2> processStates;
72 std::unordered_set<std::pair<const void*, const void*>, simgrid::xbt::hash<std::pair<const void*, const void*>>>
77 compared_pointers.clear();
80 int initHeapInformation(xbt_mheap_t heap1, xbt_mheap_t heap2, const std::vector<simgrid::mc::IgnoredHeapRegion>& i1,
81 const std::vector<simgrid::mc::IgnoredHeapRegion>& i2);
83 template <int rank> HeapArea& equals_to_(std::size_t i, std::size_t j)
85 return processStates[rank - 1].equals_to[MAX_FRAGMENT_PER_BLOCK * i + j];
87 template <int rank> Type*& types_(std::size_t i, std::size_t j)
89 return processStates[rank - 1].types[MAX_FRAGMENT_PER_BLOCK * i + j];
92 template <int rank> HeapArea const& equals_to_(std::size_t i, std::size_t j) const
94 return processStates[rank - 1].equals_to[MAX_FRAGMENT_PER_BLOCK * i + j];
96 template <int rank> Type* const& types_(std::size_t i, std::size_t j) const
98 return processStates[rank - 1].types[MAX_FRAGMENT_PER_BLOCK * i + j];
101 /** Check whether two blocks are known to be matching
103 * @param b1 Block of state 1
104 * @param b2 Block of state 2
105 * @return if the blocks are known to be matching
107 bool blocksEqual(int b1, int b2) const
109 return this->equals_to_<1>(b1, 0).block_ == b2 && this->equals_to_<2>(b2, 0).block_ == b1;
112 /** Check whether two fragments are known to be matching
114 * @param b1 Block of state 1
115 * @param f1 Fragment of state 1
116 * @param b2 Block of state 2
117 * @param f2 Fragment of state 2
118 * @return if the fragments are known to be matching
120 int fragmentsEqual(int b1, int f1, int b2, int f2) const
122 return this->equals_to_<1>(b1, f1).block_ == b2 && this->equals_to_<1>(b1, f1).fragment_ == f2 &&
123 this->equals_to_<2>(b2, f2).block_ == b1 && this->equals_to_<2>(b2, f2).fragment_ == f1;
126 void match_equals(HeapLocationPairs* list);
132 /************************************************************************************/
134 static ssize_t heap_comparison_ignore_size(const std::vector<simgrid::mc::IgnoredHeapRegion>* ignore_list,
138 int end = ignore_list->size() - 1;
140 while (start <= end) {
141 unsigned int cursor = (start + end) / 2;
142 simgrid::mc::IgnoredHeapRegion const& region = (*ignore_list)[cursor];
143 if (region.address == address)
145 if (region.address < address)
147 if (region.address > address)
154 static bool is_stack(const void *address)
156 for (auto const& stack : mc_model_checker->process().stack_areas())
157 if (address == stack.address)
162 // TODO, this should depend on the snapshot?
163 static bool is_block_stack(int block)
165 for (auto const& stack : mc_model_checker->process().stack_areas())
166 if (block == stack.block)
174 void StateComparator::match_equals(HeapLocationPairs* list)
176 for (auto const& pair : *list) {
177 if (pair[0].fragment_ != -1) {
178 this->equals_to_<1>(pair[0].block_, pair[0].fragment_) = simgrid::mc::HeapArea(pair[1].block_, pair[1].fragment_);
179 this->equals_to_<2>(pair[1].block_, pair[1].fragment_) = simgrid::mc::HeapArea(pair[0].block_, pair[0].fragment_);
181 this->equals_to_<1>(pair[0].block_, 0) = simgrid::mc::HeapArea(pair[1].block_, pair[1].fragment_);
182 this->equals_to_<2>(pair[1].block_, 0) = simgrid::mc::HeapArea(pair[0].block_, pair[0].fragment_);
187 void ProcessComparisonState::initHeapInformation(xbt_mheap_t heap, const std::vector<simgrid::mc::IgnoredHeapRegion>& i)
189 auto heaplimit = heap->heaplimit;
190 this->heapsize = heap->heapsize;
191 this->to_ignore = &i;
192 this->equals_to.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, HeapArea());
193 this->types.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, nullptr);
196 int StateComparator::initHeapInformation(xbt_mheap_t heap1, xbt_mheap_t heap2,
197 const std::vector<simgrid::mc::IgnoredHeapRegion>& i1,
198 const std::vector<simgrid::mc::IgnoredHeapRegion>& i2)
200 if ((heap1->heaplimit != heap2->heaplimit) || (heap1->heapsize != heap2->heapsize))
202 this->heaplimit = heap1->heaplimit;
203 this->std_heap_copy = *mc_model_checker->process().get_heap();
204 this->processStates[0].initHeapInformation(heap1, i1);
205 this->processStates[1].initHeapInformation(heap2, i2);
209 // TODO, have a robust way to find it in O(1)
210 static inline Region* MC_get_heap_region(const Snapshot& snapshot)
212 for (auto const& region : snapshot.snapshot_regions_)
213 if (region->region_type() == simgrid::mc::RegionType::Heap)
215 xbt_die("No heap region");
218 static bool heap_area_differ(StateComparator& state, const void* area1, const void* area2, const Snapshot& snapshot1,
219 const Snapshot& snapshot2, HeapLocationPairs* previous, Type* type, int pointer_level);
221 static bool mmalloc_heap_differ(simgrid::mc::StateComparator& state, const simgrid::mc::Snapshot& snapshot1,
222 const simgrid::mc::Snapshot& snapshot2)
224 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
226 /* Check busy blocks */
229 malloc_info heapinfo_temp1;
230 malloc_info heapinfo_temp2;
231 malloc_info heapinfo_temp2b;
233 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
234 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
236 // This is the address of std_heap->heapinfo in the application process:
237 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
239 // This is in snapshot do not use them directly:
240 const malloc_info* heapinfos1 =
241 snapshot1.read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
242 const malloc_info* heapinfos2 =
243 snapshot2.read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
245 while (i1 < state.heaplimit) {
247 const malloc_info* heapinfo1 =
248 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[i1], sizeof(malloc_info));
249 const malloc_info* heapinfo2 =
250 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[i1], sizeof(malloc_info));
252 if (heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type == MMALLOC_TYPE_HEAPINFO) { /* Free block */
257 xbt_assert(heapinfo1->type >= 0, "Unkown mmalloc block type: %d", heapinfo1->type);
259 void* addr_block1 = ((void*)(((ADDR2UINT(i1)) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase));
261 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
263 if (is_stack(addr_block1)) {
264 for (size_t k = 0; k < heapinfo1->busy_block.size; k++)
265 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
266 for (size_t k = 0; k < heapinfo2->busy_block.size; k++)
267 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
268 i1 += heapinfo1->busy_block.size;
272 if (state.equals_to_<1>(i1, 0).valid_) {
280 /* Try first to associate to same block in the other heap */
281 if (heapinfo2->type == heapinfo1->type && state.equals_to_<2>(i1, 0).valid_ == 0) {
282 void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
283 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
284 for (size_t k = 1; k < heapinfo2->busy_block.size; k++)
285 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
286 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
287 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
289 i1 += heapinfo1->busy_block.size;
293 while (i2 < state.heaplimit && not equal) {
295 void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
302 const malloc_info* heapinfo2b =
303 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
305 if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
310 if (state.equals_to_<2>(i2, 0).valid_) {
315 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
316 for (size_t k = 1; k < heapinfo2b->busy_block.size; k++)
317 state.equals_to_<2>(i2 + k, 0) = HeapArea(i1, -1);
318 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
319 state.equals_to_<1>(i1 + k, 0) = HeapArea(i2, -1);
321 i1 += heapinfo1->busy_block.size;
328 XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
332 } else { /* Fragmented block */
334 for (size_t j1 = 0; j1 < (size_t)(BLOCKSIZE >> heapinfo1->type); j1++) {
336 if (heapinfo1->busy_frag.frag_size[j1] == -1) /* Free fragment_ */
339 if (state.equals_to_<1>(i1, j1).valid_)
342 void* addr_frag1 = (void*)((char*)addr_block1 + (j1 << heapinfo1->type));
347 /* Try first to associate to same fragment_ in the other heap */
348 if (heapinfo2->type == heapinfo1->type && not state.equals_to_<2>(i1, j1).valid_) {
349 void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
350 void* addr_frag2 = (void*)((char*)addr_block2 + (j1 << heapinfo2->type));
351 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0))
355 while (i2 < state.heaplimit && not equal) {
357 const malloc_info* heapinfo2b =
358 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
360 if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
365 // We currently do not match fragments with unfragmented blocks (maybe we should).
366 if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
371 xbt_assert(heapinfo2b->type >= 0, "Unkown mmalloc block type: %d", heapinfo2b->type);
373 for (size_t j2 = 0; j2 < (size_t)(BLOCKSIZE >> heapinfo2b->type); j2++) {
375 if (i2 == i1 && j2 == j1)
378 if (state.equals_to_<2>(i2, j2).valid_)
381 void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
382 void* addr_frag2 = (void*)((char*)addr_block2 + (j2 << heapinfo2b->type));
384 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
394 XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
395 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 malloc_info* heapinfo1 =
407 (const 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 malloc_info* heapinfo2 =
426 (const 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]);
451 * @param real_area1 Process address for state 1
452 * @param real_area2 Process address for state 2
453 * @param snapshot1 Snapshot of state 1
454 * @param snapshot2 Snapshot of state 2
457 * @param check_ignore
458 * @return true when different, false otherwise (same or unknown)
460 static bool heap_area_differ_without_type(simgrid::mc::StateComparator& state, const void* real_area1,
461 const void* real_area2, const simgrid::mc::Snapshot& snapshot1,
462 const simgrid::mc::Snapshot& snapshot2, HeapLocationPairs* previous, int size,
465 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
466 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
467 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
469 for (int i = 0; i < size; ) {
471 if (check_ignore > 0) {
472 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, (const char*)real_area1 + i);
474 ssize_t ignore2 = heap_comparison_ignore_size(state.processStates[1].to_ignore, (const char*)real_area2 + i);
475 if (ignore2 == ignore1) {
488 if (MC_snapshot_region_memcmp((const char*)real_area1 + i, heap_region1, (const char*)real_area2 + i, heap_region2,
491 int pointer_align = (i / sizeof(void *)) * sizeof(void *);
492 const void* addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + pointer_align)));
493 const void* addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + pointer_align)));
495 if (process.in_maestro_stack(remote(addr_pointed1)) && process.in_maestro_stack(remote(addr_pointed2))) {
496 i = pointer_align + sizeof(void *);
500 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)) {
501 // Both addresses are in the heap:
502 if (heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, nullptr, 0))
504 i = pointer_align + sizeof(void *);
520 * @param real_area1 Process address for state 1
521 * @param real_area2 Process address for state 2
522 * @param snapshot1 Snapshot of state 1
523 * @param snapshot2 Snapshot of state 2
526 * @param area_size either a byte_size or an elements_count (?)
527 * @param check_ignore
528 * @param pointer_level
529 * @return true when different, false otherwise (same or unknown)
531 static bool heap_area_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
532 const void* real_area2, const simgrid::mc::Snapshot& snapshot1,
533 const simgrid::mc::Snapshot& snapshot2, HeapLocationPairs* previous,
534 simgrid::mc::Type* type, int area_size, int check_ignore, int pointer_level)
536 // HACK: This should not happen but in practice, there are some
537 // DW_TAG_typedef without an associated DW_AT_type:
538 //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
539 // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
540 // <538837> DW_AT_decl_file : 98
541 // <538838> DW_AT_decl_line : 37
545 if (is_stack(real_area1) && is_stack(real_area2))
548 if (check_ignore > 0) {
549 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
550 if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
554 simgrid::mc::Type* subtype;
555 simgrid::mc::Type* subsubtype;
557 const void* addr_pointed1;
558 const void* addr_pointed2;
560 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
561 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
563 switch (type->type) {
564 case DW_TAG_unspecified_type:
567 case DW_TAG_base_type:
568 if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
569 if (real_area1 == real_area2)
572 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
574 if (area_size != -1 && type->byte_size != area_size)
577 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
580 case DW_TAG_enumeration_type:
581 if (area_size != -1 && type->byte_size != area_size)
583 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
586 case DW_TAG_const_type:
587 case DW_TAG_volatile_type:
588 return heap_area_differ_with_type(state, real_area1, real_area2, snapshot1, snapshot2, previous, type->subtype,
589 area_size, check_ignore, pointer_level);
591 case DW_TAG_array_type:
592 subtype = type->subtype;
593 switch (subtype->type) {
594 case DW_TAG_unspecified_type:
597 case DW_TAG_base_type:
598 case DW_TAG_enumeration_type:
599 case DW_TAG_pointer_type:
600 case DW_TAG_reference_type:
601 case DW_TAG_rvalue_reference_type:
602 case DW_TAG_structure_type:
603 case DW_TAG_class_type:
604 case DW_TAG_union_type:
605 if (subtype->full_type)
606 subtype = subtype->full_type;
607 elm_size = subtype->byte_size;
609 // TODO, just remove the type indirection?
610 case DW_TAG_const_type:
612 case DW_TAG_volatile_type:
613 subsubtype = subtype->subtype;
614 if (subsubtype->full_type)
615 subsubtype = subsubtype->full_type;
616 elm_size = subsubtype->byte_size;
621 for (int i = 0; i < type->element_count; i++) {
622 // TODO, add support for variable stride (DW_AT_byte_stride)
623 if (heap_area_differ_with_type(state, (const char*)real_area1 + (i * elm_size),
624 (const char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
625 type->subtype, subtype->byte_size, check_ignore, pointer_level))
630 case DW_TAG_reference_type:
631 case DW_TAG_rvalue_reference_type:
632 case DW_TAG_pointer_type:
633 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
634 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
635 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
636 return (addr_pointed1 != addr_pointed2);
639 if (pointer_level <= 1) {
640 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
641 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
642 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2))
643 return heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, type->subtype,
646 return (addr_pointed1 != addr_pointed2);
648 for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
649 addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + i * sizeof(void*))));
650 addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + i * sizeof(void*))));
651 bool differ = snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)
652 ? heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
653 type->subtype, pointer_level)
654 : addr_pointed1 != addr_pointed2;
660 case DW_TAG_structure_type:
661 case DW_TAG_class_type:
663 type = type->full_type;
664 if (area_size != -1 && type->byte_size != area_size) {
665 if (area_size <= type->byte_size || area_size % type->byte_size != 0)
667 for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
668 if (heap_area_differ_with_type(state, (const char*)real_area1 + i * type->byte_size,
669 (const char*)real_area2 + i * type->byte_size, snapshot1, snapshot2, previous,
670 type, -1, check_ignore, 0))
674 for (simgrid::mc::Member& member : type->members) {
675 // TODO, optimize this? (for the offset case)
676 void* real_member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
677 void* real_member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
678 if (heap_area_differ_with_type(state, real_member1, real_member2, snapshot1, snapshot2, previous,
679 member.type, -1, check_ignore, 0))
685 case DW_TAG_union_type:
686 return heap_area_differ_without_type(state, real_area1, real_area2, snapshot1, snapshot2, previous,
687 type->byte_size, check_ignore);
694 /** Infer the type of a part of the block from the type of the block
696 * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
698 * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
700 * @param type DWARF type ID of the root address
702 * @return DWARF type ID for given offset
704 static simgrid::mc::Type* get_offset_type(void* real_base_address, simgrid::mc::Type* type, int offset, int area_size,
705 const simgrid::mc::Snapshot& snapshot)
708 // Beginning of the block, the inferred variable type if the type of the block:
712 switch (type->type) {
714 case DW_TAG_structure_type:
715 case DW_TAG_class_type:
717 type = type->full_type;
718 if (area_size != -1 && type->byte_size != area_size) {
719 if (area_size > type->byte_size && area_size % type->byte_size == 0)
725 for (simgrid::mc::Member& member : type->members) {
726 if (member.has_offset_location()) {
727 // We have the offset, use it directly (shortcut):
728 if (member.offset() == offset)
731 void* real_member = simgrid::dwarf::resolve_member(real_base_address, type, &member, &snapshot);
732 if ((char*)real_member - (char*)real_base_address == offset)
739 /* FIXME: other cases ? */
747 * @param area1 Process address for state 1
748 * @param area2 Process address for state 2
749 * @param snapshot1 Snapshot of state 1
750 * @param snapshot2 Snapshot of state 2
751 * @param previous Pairs of blocks already compared on the current path (or nullptr)
752 * @param type_id Type of variable
753 * @param pointer_level
754 * @return true when different, false otherwise (same or unknown)
756 static bool heap_area_differ(simgrid::mc::StateComparator& state, const void* area1, const void* area2,
757 const simgrid::mc::Snapshot& snapshot1, const simgrid::mc::Snapshot& snapshot2,
758 HeapLocationPairs* previous, simgrid::mc::Type* type, int pointer_level)
760 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
765 int check_ignore = 0;
773 simgrid::mc::Type* new_type1 = nullptr;
774 simgrid::mc::Type* new_type2 = nullptr;
776 bool match_pairs = false;
778 // This is the address of std_heap->heapinfo in the application process:
779 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
781 const malloc_info* heapinfos1 = snapshot1.read(remote((const malloc_info**)heapinfo_address));
782 const malloc_info* heapinfos2 = snapshot2.read(remote((const malloc_info**)heapinfo_address));
784 malloc_info heapinfo_temp1;
785 malloc_info heapinfo_temp2;
787 simgrid::mc::HeapLocationPairs current;
788 if (previous == nullptr) {
794 block1 = ((char*)area1 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
795 block2 = ((char*)area2 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
797 // If either block is a stack block:
798 if (is_block_stack((int) block1) && is_block_stack((int) block2)) {
799 previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}});
801 state.match_equals(previous);
805 // If either block is not in the expected area of memory:
806 if (((char*)area1 < (char*)state.std_heap_copy.heapbase) || (block1 > (ssize_t)state.processStates[0].heapsize) ||
807 (block1 < 1) || ((char*)area2 < (char*)state.std_heap_copy.heapbase) ||
808 (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
812 // Process address of the block:
813 void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
814 void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
818 type = type->full_type;
820 // This assume that for "boring" types (volatile ...) byte_size is absent:
821 while (type->byte_size == 0 && type->subtype != nullptr)
822 type = type->subtype;
825 if (type->type == DW_TAG_pointer_type ||
826 (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
829 type_size = type->byte_size;
833 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
834 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
836 const malloc_info* heapinfo1 =
837 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info));
838 const malloc_info* heapinfo2 =
839 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info));
841 if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
842 && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
845 state.match_equals(previous);
849 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
852 // TODO, lookup variable type from block type as done for fragmented blocks
854 if (state.equals_to_<1>(block1, 0).valid_ && state.equals_to_<2>(block2, 0).valid_ &&
855 state.blocksEqual(block1, block2)) {
857 state.match_equals(previous);
861 if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
862 type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
863 (type->name.empty() || type->name == "struct s_smx_context")) {
865 state.match_equals(previous);
869 if (heapinfo1->busy_block.size != heapinfo2->busy_block.size ||
870 heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
873 if (not previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}}).second) {
875 state.match_equals(previous);
879 size = heapinfo1->busy_block.busy_size;
881 // Remember (basic) type inference.
882 // The current data structure only allows us to do this for the whole block.
883 if (type != nullptr && area1 == real_addr_block1)
884 state.types_<1>(block1, 0) = type;
885 if (type != nullptr && area2 == real_addr_block2)
886 state.types_<2>(block2, 0) = type;
890 state.match_equals(previous);
894 if (heapinfo1->busy_block.ignore > 0
895 && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
896 check_ignore = heapinfo1->busy_block.ignore;
898 } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
901 ssize_t frag1 = ((uintptr_t)(ADDR2UINT(area1) % (BLOCKSIZE))) >> heapinfo1->type;
902 ssize_t frag2 = ((uintptr_t)(ADDR2UINT(area2) % (BLOCKSIZE))) >> heapinfo2->type;
904 // Process address of the fragment_:
905 void* real_addr_frag1 = (void*)((char*)real_addr_block1 + (frag1 << heapinfo1->type));
906 void* real_addr_frag2 = (void*)((char*)real_addr_block2 + (frag2 << heapinfo2->type));
908 // Check the size of the fragments against the size of the type:
909 if (type_size != -1) {
910 if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
912 state.match_equals(previous);
916 if (type_size != heapinfo1->busy_frag.frag_size[frag1]
917 || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
919 state.match_equals(previous);
924 // Check if the blocks are already matched together:
925 if (state.equals_to_<1>(block1, frag1).valid_ && state.equals_to_<2>(block2, frag2).valid_ && offset1 == offset2 &&
926 state.fragmentsEqual(block1, frag1, block2, frag2)) {
928 state.match_equals(previous);
931 // Compare the size of both fragments:
932 if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
933 if (type_size == -1) {
935 state.match_equals(previous);
941 // Size of the fragment_:
942 size = heapinfo1->busy_frag.frag_size[frag1];
944 // Remember (basic) type inference.
945 // The current data structure only allows us to do this for the whole fragment_.
946 if (type != nullptr && area1 == real_addr_frag1)
947 state.types_<1>(block1, frag1) = type;
948 if (type != nullptr && area2 == real_addr_frag2)
949 state.types_<2>(block2, frag2) = type;
951 // The type of the variable is already known:
953 new_type1 = new_type2 = type;
955 // Type inference from the block type.
956 else if (state.types_<1>(block1, frag1) != nullptr || state.types_<2>(block2, frag2) != nullptr) {
958 offset1 = (char*)area1 - (char*)real_addr_frag1;
959 offset2 = (char*)area2 - (char*)real_addr_frag2;
961 if (state.types_<1>(block1, frag1) != nullptr && state.types_<2>(block2, frag2) != nullptr) {
962 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
963 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset1, size, snapshot2);
964 } else if (state.types_<1>(block1, frag1) != nullptr) {
965 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
966 new_type2 = get_offset_type(real_addr_frag2, state.types_<1>(block1, frag1), offset2, size, snapshot2);
967 } else if (state.types_<2>(block2, frag2) != nullptr) {
968 new_type1 = get_offset_type(real_addr_frag1, state.types_<2>(block2, frag2), offset1, size, snapshot1);
969 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset2, size, snapshot2);
972 state.match_equals(previous);
976 if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
979 while (type->byte_size == 0 && type->subtype != nullptr)
980 type = type->subtype;
981 new_size1 = type->byte_size;
984 while (type->byte_size == 0 && type->subtype != nullptr)
985 type = type->subtype;
986 new_size2 = type->byte_size;
990 state.match_equals(previous);
995 if (new_size1 > 0 && new_size1 == new_size2) {
1000 if (offset1 == 0 && offset2 == 0 &&
1001 not previous->insert(HeapLocationPair{{HeapLocation(block1, frag1), HeapLocation(block2, frag2)}}).second) {
1003 state.match_equals(previous);
1009 state.match_equals(previous);
1013 if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
1014 (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
1015 check_ignore = heapinfo1->busy_frag.ignore[frag1];
1020 /* Start comparison */
1022 type ? heap_area_differ_with_type(state, area1, area2, snapshot1, snapshot2, previous, type, size, check_ignore,
1024 : heap_area_differ_without_type(state, area1, area2, snapshot1, snapshot2, previous, size, check_ignore);
1029 state.match_equals(previous);
1036 /************************** Snapshot comparison *******************************/
1037 /******************************************************************************/
1039 static bool areas_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
1040 const simgrid::mc::Snapshot& snapshot1, simgrid::mc::Region* region1,
1041 const void* real_area2, const simgrid::mc::Snapshot& snapshot2,
1042 simgrid::mc::Region* region2, simgrid::mc::Type* type, int pointer_level)
1044 simgrid::mc::Type* subtype;
1045 simgrid::mc::Type* subsubtype;
1049 xbt_assert(type != nullptr);
1050 switch (type->type) {
1051 case DW_TAG_unspecified_type:
1054 case DW_TAG_base_type:
1055 case DW_TAG_enumeration_type:
1056 case DW_TAG_union_type:
1057 return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
1058 case DW_TAG_typedef:
1059 case DW_TAG_volatile_type:
1060 case DW_TAG_const_type:
1061 return areas_differ_with_type(state, real_area1, snapshot1, region1, real_area2, snapshot2, region2,
1062 type->subtype, pointer_level);
1063 case DW_TAG_array_type:
1064 subtype = type->subtype;
1065 switch (subtype->type) {
1066 case DW_TAG_unspecified_type:
1069 case DW_TAG_base_type:
1070 case DW_TAG_enumeration_type:
1071 case DW_TAG_pointer_type:
1072 case DW_TAG_reference_type:
1073 case DW_TAG_rvalue_reference_type:
1074 case DW_TAG_structure_type:
1075 case DW_TAG_class_type:
1076 case DW_TAG_union_type:
1077 if (subtype->full_type)
1078 subtype = subtype->full_type;
1079 elm_size = subtype->byte_size;
1081 case DW_TAG_const_type:
1082 case DW_TAG_typedef:
1083 case DW_TAG_volatile_type:
1084 subsubtype = subtype->subtype;
1085 if (subsubtype->full_type)
1086 subsubtype = subsubtype->full_type;
1087 elm_size = subsubtype->byte_size;
1092 for (i = 0; i < type->element_count; i++) {
1093 size_t off = i * elm_size;
1094 if (areas_differ_with_type(state, (const char*)real_area1 + off, snapshot1, region1,
1095 (const char*)real_area2 + off, snapshot2, region2, type->subtype, pointer_level))
1099 case DW_TAG_pointer_type:
1100 case DW_TAG_reference_type:
1101 case DW_TAG_rvalue_reference_type: {
1102 const void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
1103 const void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
1105 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
1106 return (addr_pointed1 != addr_pointed2);
1107 if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
1109 if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
1111 if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
1116 // Some cases are not handled here:
1117 // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
1118 // * a pointer leads to the read-only segment of the current object
1119 // * a pointer lead to a different ELF object
1121 if (snapshot1.on_heap(addr_pointed1)) {
1122 if (not snapshot2.on_heap(addr_pointed2))
1124 // The pointers are both in the heap:
1125 return simgrid::mc::heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, nullptr,
1126 type->subtype, pointer_level);
1128 } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
1129 // The pointers are both in the current object R/W segment:
1130 if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
1132 if (not type->type_id)
1133 return (addr_pointed1 != addr_pointed2);
1135 return areas_differ_with_type(state, addr_pointed1, snapshot1, region1, addr_pointed2, snapshot2, region2,
1136 type->subtype, pointer_level);
1139 // TODO, We do not handle very well the case where
1140 // it belongs to a different (non-heap) region from the current one.
1142 return (addr_pointed1 != addr_pointed2);
1145 case DW_TAG_structure_type:
1146 case DW_TAG_class_type:
1147 for (simgrid::mc::Member& member : type->members) {
1148 void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
1149 void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
1150 simgrid::mc::Region* subregion1 = snapshot1.get_region(member1, region1); // region1 is hinted
1151 simgrid::mc::Region* subregion2 = snapshot2.get_region(member2, region2); // region2 is hinted
1152 if (areas_differ_with_type(state, member1, snapshot1, subregion1, member2, snapshot2, subregion2, member.type,
1157 case DW_TAG_subroutine_type:
1160 XBT_VERB("Unknown case: %d", type->type);
1167 static bool global_variables_differ(simgrid::mc::StateComparator& state, simgrid::mc::ObjectInformation* object_info,
1168 simgrid::mc::Region* r1, simgrid::mc::Region* r2,
1169 const simgrid::mc::Snapshot& snapshot1, const simgrid::mc::Snapshot& snapshot2)
1171 xbt_assert(r1 && r2, "Missing region.");
1173 const std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
1175 for (simgrid::mc::Variable const& current_var : variables) {
1177 // If the variable is not in this object, skip it:
1178 // We do not expect to find a pointer to something which is not reachable
1179 // by the global variables.
1180 if ((char *) current_var.address < (char *) object_info->start_rw
1181 || (char *) current_var.address > (char *) object_info->end_rw)
1184 simgrid::mc::Type* bvariable_type = current_var.type;
1185 if (areas_differ_with_type(state, current_var.address, snapshot1, r1, current_var.address, snapshot2, r2,
1186 bvariable_type, 0)) {
1187 XBT_VERB("Global variable %s (%p) is different between snapshots", current_var.name.c_str(), current_var.address);
1195 static bool local_variables_differ(simgrid::mc::StateComparator& state, const simgrid::mc::Snapshot& snapshot1,
1196 const simgrid::mc::Snapshot& snapshot2, const_mc_snapshot_stack_t stack1,
1197 const_mc_snapshot_stack_t stack2)
1199 if (stack1->local_variables.size() != stack2->local_variables.size()) {
1200 XBT_VERB("Different number of local variables");
1204 for (unsigned int cursor = 0; cursor < stack1->local_variables.size(); cursor++) {
1205 const_local_variable_t current_var1 = &stack1->local_variables[cursor];
1206 const_local_variable_t current_var2 = &stack2->local_variables[cursor];
1207 if (current_var1->name != current_var2->name || current_var1->subprogram != current_var2->subprogram ||
1208 current_var1->ip != current_var2->ip) {
1209 // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
1210 XBT_VERB("Different name of variable (%s - %s) or frame (%s - %s) or ip (%lu - %lu)", current_var1->name.c_str(),
1211 current_var2->name.c_str(), current_var1->subprogram->name.c_str(),
1212 current_var2->subprogram->name.c_str(), current_var1->ip, current_var2->ip);
1216 if (areas_differ_with_type(state, current_var1->address, snapshot1, snapshot1.get_region(current_var1->address),
1217 current_var2->address, snapshot2, snapshot2.get_region(current_var2->address),
1218 current_var1->type, 0)) {
1219 XBT_VERB("Local variable %s (%p - %p) in frame %s is different between snapshots", current_var1->name.c_str(),
1220 current_var1->address, current_var2->address, current_var1->subprogram->name.c_str());
1230 bool snapshot_equal(const Snapshot* s1, const Snapshot* s2)
1232 // TODO, make this a field of ModelChecker or something similar
1233 static StateComparator state_comparator;
1235 const RemoteClient& process = mc_model_checker->process();
1237 if (s1->hash_ != s2->hash_) {
1238 XBT_VERB("(%d - %d) Different hash: 0x%" PRIx64 "--0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_,
1242 XBT_VERB("(%d - %d) Same hash: 0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_);
1244 /* Compare enabled processes */
1245 if (s1->enabled_processes_ != s2->enabled_processes_) {
1246 XBT_VERB("(%d - %d) Different amount of enabled processes", s1->num_state_, s2->num_state_);
1250 /* Compare size of stacks */
1251 for (unsigned long i = 0; i < s1->stacks_.size(); i++) {
1252 size_t size_used1 = s1->stack_sizes_[i];
1253 size_t size_used2 = s2->stack_sizes_[i];
1254 if (size_used1 != size_used2) {
1255 XBT_VERB("(%d - %d) Different size used in stacks: %zu - %zu", s1->num_state_, s2->num_state_, size_used1,
1261 /* Init heap information used in heap comparison algorithm */
1263 static_cast<xbt_mheap_t>(s1->read_bytes(alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
1264 remote(process.heap_address), simgrid::mc::ReadOptions::lazy()));
1266 static_cast<xbt_mheap_t>(s2->read_bytes(alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
1267 remote(process.heap_address), simgrid::mc::ReadOptions::lazy()));
1268 if (state_comparator.initHeapInformation(heap1, heap2, s1->to_ignore_, s2->to_ignore_) == -1) {
1269 XBT_VERB("(%d - %d) Different heap information", s1->num_state_, s2->num_state_);
1273 /* Stacks comparison */
1274 for (unsigned int cursor = 0; cursor < s1->stacks_.size(); cursor++) {
1275 const_mc_snapshot_stack_t stack1 = &s1->stacks_[cursor];
1276 const_mc_snapshot_stack_t stack2 = &s2->stacks_[cursor];
1278 if (local_variables_differ(state_comparator, *s1, *s2, stack1, stack2)) {
1279 XBT_VERB("(%d - %d) Different local variables between stacks %u", s1->num_state_, s2->num_state_, cursor + 1);
1284 size_t regions_count = s1->snapshot_regions_.size();
1285 if (regions_count != s2->snapshot_regions_.size())
1288 for (size_t k = 0; k != regions_count; ++k) {
1289 Region* region1 = s1->snapshot_regions_[k].get();
1290 Region* region2 = s2->snapshot_regions_[k].get();
1293 if (region1->region_type() != RegionType::Data)
1296 xbt_assert(region1->region_type() == region2->region_type());
1297 xbt_assert(region1->object_info() == region2->object_info());
1298 xbt_assert(region1->object_info());
1300 /* Compare global variables */
1301 if (global_variables_differ(state_comparator, region1->object_info(), region1, region2, *s1, *s2)) {
1302 std::string const& name = region1->object_info()->file_name;
1303 XBT_VERB("(%d - %d) Different global variables in %s", s1->num_state_, s2->num_state_, name.c_str());
1309 if (mmalloc_heap_differ(state_comparator, *s1, *s2)) {
1310 XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", s1->num_state_, s2->num_state_);
1314 XBT_VERB("(%d - %d) No difference found", s1->num_state_, s2->num_state_);