1 /* Copyright (c) 2008-2021. 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, xbt, "Logging specific to mc_compare in mc");
16 using simgrid::mc::remote;
21 /*********************************** Heap comparison ***********************************/
22 /***************************************************************************************/
29 HeapLocation() = default;
30 explicit HeapLocation(int block, int fragment = 0) : block_(block), fragment_(fragment) {}
32 bool operator==(HeapLocation const& that) const
34 return block_ == that.block_ && fragment_ == that.fragment_;
36 bool operator<(HeapLocation const& that) const
38 return std::make_pair(block_, fragment_) < std::make_pair(that.block_, that.fragment_);
42 using HeapLocationPair = std::array<HeapLocation, 2>;
43 using HeapLocationPairs = std::set<HeapLocationPair>;
45 class HeapArea : public HeapLocation {
49 explicit HeapArea(int block) : valid_(true) { block_ = block; }
50 HeapArea(int block, int fragment) : valid_(true)
57 class ProcessComparisonState {
59 const std::vector<IgnoredHeapRegion>* to_ignore = nullptr;
60 std::vector<HeapArea> equals_to;
61 std::vector<Type*> types;
62 std::size_t heapsize = 0;
64 void initHeapInformation(const s_xbt_mheap_t* heap, const std::vector<IgnoredHeapRegion>& i);
67 class StateComparator {
69 s_xbt_mheap_t std_heap_copy;
70 std::size_t heaplimit;
71 std::array<ProcessComparisonState, 2> processStates;
73 std::unordered_set<std::pair<const void*, const void*>, simgrid::xbt::hash<std::pair<const void*, const void*>>>
78 compared_pointers.clear();
81 int initHeapInformation(const s_xbt_mheap_t* heap1, const s_xbt_mheap_t* heap2,
82 const std::vector<IgnoredHeapRegion>& i1, const std::vector<IgnoredHeapRegion>& i2);
84 template <int rank> HeapArea& equals_to_(std::size_t i, std::size_t j)
86 return processStates[rank - 1].equals_to[MAX_FRAGMENT_PER_BLOCK * i + j];
88 template <int rank> Type*& types_(std::size_t i, std::size_t j)
90 return processStates[rank - 1].types[MAX_FRAGMENT_PER_BLOCK * i + j];
93 template <int rank> HeapArea const& equals_to_(std::size_t i, std::size_t j) const
95 return processStates[rank - 1].equals_to[MAX_FRAGMENT_PER_BLOCK * i + j];
97 template <int rank> Type* const& types_(std::size_t i, std::size_t j) const
99 return processStates[rank - 1].types[MAX_FRAGMENT_PER_BLOCK * i + j];
102 /** Check whether two blocks are known to be matching
104 * @param b1 Block of state 1
105 * @param b2 Block of state 2
106 * @return if the blocks are known to be matching
108 bool blocksEqual(int b1, int b2) const
110 return this->equals_to_<1>(b1, 0).block_ == b2 && this->equals_to_<2>(b2, 0).block_ == b1;
113 /** Check whether two fragments are known to be matching
115 * @param b1 Block of state 1
116 * @param f1 Fragment of state 1
117 * @param b2 Block of state 2
118 * @param f2 Fragment of state 2
119 * @return if the fragments are known to be matching
121 int fragmentsEqual(int b1, int f1, int b2, int f2) const
123 return this->equals_to_<1>(b1, f1).block_ == b2 && this->equals_to_<1>(b1, f1).fragment_ == f2 &&
124 this->equals_to_<2>(b2, f2).block_ == b1 && this->equals_to_<2>(b2, f2).fragment_ == f1;
127 void match_equals(const HeapLocationPairs* list);
131 } // namespace simgrid
133 /************************************************************************************/
135 static ssize_t heap_comparison_ignore_size(const std::vector<simgrid::mc::IgnoredHeapRegion>* ignore_list,
138 auto pos = std::lower_bound(ignore_list->begin(), ignore_list->end(), address,
139 [](auto const& reg, auto const* addr) { return reg.address < addr; });
140 return (pos != ignore_list->end() && pos->address == address) ? pos->size : -1;
143 static bool is_stack(const void *address)
145 auto const& stack_areas = mc_model_checker->get_remote_simulation().stack_areas();
146 return std::any_of(stack_areas.begin(), stack_areas.end(),
147 [address](auto const& stack) { return stack.address == address; });
150 // TODO, this should depend on the snapshot?
151 static bool is_block_stack(int block)
153 auto const& stack_areas = mc_model_checker->get_remote_simulation().stack_areas();
154 return std::any_of(stack_areas.begin(), stack_areas.end(),
155 [block](auto const& stack) { return stack.block == block; });
161 void StateComparator::match_equals(const HeapLocationPairs* list)
163 for (auto const& pair : *list) {
164 if (pair[0].fragment_ != -1) {
165 this->equals_to_<1>(pair[0].block_, pair[0].fragment_) = HeapArea(pair[1].block_, pair[1].fragment_);
166 this->equals_to_<2>(pair[1].block_, pair[1].fragment_) = HeapArea(pair[0].block_, pair[0].fragment_);
168 this->equals_to_<1>(pair[0].block_, 0) = HeapArea(pair[1].block_, pair[1].fragment_);
169 this->equals_to_<2>(pair[1].block_, 0) = HeapArea(pair[0].block_, pair[0].fragment_);
174 void ProcessComparisonState::initHeapInformation(const s_xbt_mheap_t* heap, const std::vector<IgnoredHeapRegion>& i)
176 auto heaplimit = heap->heaplimit;
177 this->heapsize = heap->heapsize;
178 this->to_ignore = &i;
179 this->equals_to.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, HeapArea());
180 this->types.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, nullptr);
183 int StateComparator::initHeapInformation(const s_xbt_mheap_t* heap1, const s_xbt_mheap_t* heap2,
184 const std::vector<IgnoredHeapRegion>& i1,
185 const std::vector<IgnoredHeapRegion>& i2)
187 if ((heap1->heaplimit != heap2->heaplimit) || (heap1->heapsize != heap2->heapsize))
189 this->heaplimit = heap1->heaplimit;
190 this->std_heap_copy = *mc_model_checker->get_remote_simulation().get_heap();
191 this->processStates[0].initHeapInformation(heap1, i1);
192 this->processStates[1].initHeapInformation(heap2, i2);
196 // TODO, have a robust way to find it in O(1)
197 static inline Region* MC_get_heap_region(const Snapshot& snapshot)
199 for (auto const& region : snapshot.snapshot_regions_)
200 if (region->region_type() == RegionType::Heap)
202 xbt_die("No heap region");
205 static bool heap_area_differ(StateComparator& state, const void* area1, const void* area2, const Snapshot& snapshot1,
206 const Snapshot& snapshot2, HeapLocationPairs* previous, Type* type, int pointer_level);
208 static bool mmalloc_heap_differ(StateComparator& state, const Snapshot& snapshot1, const Snapshot& snapshot2)
210 const RemoteSimulation& process = mc_model_checker->get_remote_simulation();
212 /* Check busy blocks */
215 malloc_info heapinfo_temp1;
216 malloc_info heapinfo_temp2;
217 malloc_info heapinfo_temp2b;
219 const Region* heap_region1 = MC_get_heap_region(snapshot1);
220 const Region* heap_region2 = MC_get_heap_region(snapshot2);
222 // This is the address of std_heap->heapinfo in the application process:
223 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
225 // This is in snapshot do not use them directly:
226 const malloc_info* heapinfos1 =
227 snapshot1.read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
228 const malloc_info* heapinfos2 =
229 snapshot2.read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
231 while (i1 < state.heaplimit) {
232 const auto* heapinfo1 =
233 static_cast<malloc_info*>(heap_region1->read(&heapinfo_temp1, &heapinfos1[i1], sizeof(malloc_info)));
234 const auto* heapinfo2 =
235 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2, &heapinfos2[i1], sizeof(malloc_info)));
237 if (heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type == MMALLOC_TYPE_HEAPINFO) { /* Free block */
242 xbt_assert(heapinfo1->type >= 0, "Unknown mmalloc block type: %d", heapinfo1->type);
244 void* addr_block1 = ((void*)(((ADDR2UINT(i1)) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase));
246 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
247 if (is_stack(addr_block1)) {
248 for (size_t k = 0; k < heapinfo1->busy_block.size; k++)
249 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
250 for (size_t k = 0; k < heapinfo2->busy_block.size; k++)
251 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
252 i1 += heapinfo1->busy_block.size;
256 if (state.equals_to_<1>(i1, 0).valid_) {
264 /* Try first to associate to same block in the other heap */
265 if (heapinfo2->type == heapinfo1->type && state.equals_to_<2>(i1, 0).valid_ == 0) {
266 const void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
267 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
268 for (size_t k = 1; k < heapinfo2->busy_block.size; k++)
269 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
270 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
271 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
273 i1 += heapinfo1->busy_block.size;
277 while (i2 < state.heaplimit && not equal) {
278 const void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
285 const auto* heapinfo2b =
286 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info)));
288 if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
293 if (state.equals_to_<2>(i2, 0).valid_) {
298 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
299 for (size_t k = 1; k < heapinfo2b->busy_block.size; k++)
300 state.equals_to_<2>(i2 + k, 0) = HeapArea(i1, -1);
301 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
302 state.equals_to_<1>(i1 + k, 0) = HeapArea(i2, -1);
304 i1 += heapinfo1->busy_block.size;
310 XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
313 } else { /* Fragmented block */
314 for (size_t j1 = 0; j1 < (size_t)(BLOCKSIZE >> heapinfo1->type); j1++) {
315 if (heapinfo1->busy_frag.frag_size[j1] == -1) /* Free fragment_ */
318 if (state.equals_to_<1>(i1, j1).valid_)
321 void* addr_frag1 = (char*)addr_block1 + (j1 << heapinfo1->type);
326 /* Try first to associate to same fragment_ in the other heap */
327 if (heapinfo2->type == heapinfo1->type && not state.equals_to_<2>(i1, j1).valid_) {
328 const void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
329 const void* addr_frag2 = (const char*)addr_block2 + (j1 << heapinfo2->type);
330 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0))
334 while (i2 < state.heaplimit && not equal) {
335 const auto* heapinfo2b =
336 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info)));
338 if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
343 // We currently do not match fragments with unfragmented blocks (maybe we should).
344 if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
349 xbt_assert(heapinfo2b->type >= 0, "Unknown mmalloc block type: %d", heapinfo2b->type);
351 for (size_t j2 = 0; j2 < (size_t)(BLOCKSIZE >> heapinfo2b->type); j2++) {
352 if (i2 == i1 && j2 == j1)
355 if (state.equals_to_<2>(i2, j2).valid_)
358 const void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
359 const void* addr_frag2 = (const char*)addr_block2 + (j2 << heapinfo2b->type);
361 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
370 XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
371 heapinfo1->busy_frag.frag_size[j1], addr_frag1);
379 /* All blocks/fragments are equal to another block/fragment_ ? */
380 for (size_t i = 1; i < state.heaplimit; i++) {
381 const auto* heapinfo1 =
382 static_cast<malloc_info*>(heap_region1->read(&heapinfo_temp1, &heapinfos1[i], sizeof(malloc_info)));
384 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo1->busy_block.busy_size > 0 &&
385 not state.equals_to_<1>(i, 0).valid_) {
386 XBT_DEBUG("Block %zu not found (size used = %zu)", i, heapinfo1->busy_block.busy_size);
390 if (heapinfo1->type <= 0)
392 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo1->type); j++)
393 if (i1 == state.heaplimit && heapinfo1->busy_frag.frag_size[j] > 0 && not state.equals_to_<1>(i, j).valid_) {
394 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)", i, j, heapinfo1->busy_frag.frag_size[j]);
399 for (size_t i = 1; i < state.heaplimit; i++) {
400 const auto* heapinfo2 =
401 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2, &heapinfos2[i], sizeof(malloc_info)));
402 if (heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo2->busy_block.busy_size > 0 &&
403 not state.equals_to_<2>(i, 0).valid_) {
404 XBT_DEBUG("Block %zu not found (size used = %zu)", i,
405 heapinfo2->busy_block.busy_size);
409 if (heapinfo2->type <= 0)
412 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo2->type); j++)
413 if (i1 == state.heaplimit && heapinfo2->busy_frag.frag_size[j] > 0 && not state.equals_to_<2>(i, j).valid_) {
414 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)",
415 i, j, heapinfo2->busy_frag.frag_size[j]);
425 * @param real_area1 Process address for state 1
426 * @param real_area2 Process address for state 2
427 * @param snapshot1 Snapshot of state 1
428 * @param snapshot2 Snapshot of state 2
431 * @param check_ignore
432 * @return true when different, false otherwise (same or unknown)
434 static bool heap_area_differ_without_type(StateComparator& state, const void* real_area1, const void* real_area2,
435 const Snapshot& snapshot1, const Snapshot& snapshot2,
436 HeapLocationPairs* previous, int size, int check_ignore)
438 const RemoteSimulation& process = mc_model_checker->get_remote_simulation();
439 const Region* heap_region1 = MC_get_heap_region(snapshot1);
440 const Region* heap_region2 = MC_get_heap_region(snapshot2);
442 for (int i = 0; i < size; ) {
443 if (check_ignore > 0) {
444 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, (const char*)real_area1 + i);
446 ssize_t ignore2 = heap_comparison_ignore_size(state.processStates[1].to_ignore, (const char*)real_area2 + i);
447 if (ignore2 == ignore1) {
459 if (MC_snapshot_region_memcmp((const char*)real_area1 + i, heap_region1, (const char*)real_area2 + i, heap_region2,
461 int pointer_align = (i / sizeof(void *)) * sizeof(void *);
462 const void* addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + pointer_align)));
463 const void* addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + pointer_align)));
465 if (process.in_maestro_stack(remote(addr_pointed1)) && process.in_maestro_stack(remote(addr_pointed2))) {
466 i = pointer_align + sizeof(void *);
470 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)) {
471 // Both addresses are in the heap:
472 if (heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, nullptr, 0))
474 i = pointer_align + sizeof(void *);
487 * @param real_area1 Process address for state 1
488 * @param real_area2 Process address for state 2
489 * @param snapshot1 Snapshot of state 1
490 * @param snapshot2 Snapshot of state 2
493 * @param area_size either a byte_size or an elements_count (?)
494 * @param check_ignore
495 * @param pointer_level
496 * @return true when different, false otherwise (same or unknown)
498 static bool heap_area_differ_with_type(StateComparator& state, const void* real_area1, const void* real_area2,
499 const Snapshot& snapshot1, const Snapshot& snapshot2,
500 HeapLocationPairs* previous, const Type* type, int area_size, int check_ignore,
503 // HACK: This should not happen but in practice, there are some
504 // DW_TAG_typedef without an associated DW_AT_type:
505 //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
506 // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
507 // <538837> DW_AT_decl_file : 98
508 // <538838> DW_AT_decl_line : 37
512 if (is_stack(real_area1) && is_stack(real_area2))
515 if (check_ignore > 0) {
516 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
517 if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
522 const Type* subsubtype;
524 const void* addr_pointed1;
525 const void* addr_pointed2;
527 const Region* heap_region1 = MC_get_heap_region(snapshot1);
528 const Region* heap_region2 = MC_get_heap_region(snapshot2);
530 switch (type->type) {
531 case DW_TAG_unspecified_type:
534 case DW_TAG_base_type:
535 if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
536 if (real_area1 == real_area2)
539 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
541 if (area_size != -1 && type->byte_size != area_size)
544 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
547 case DW_TAG_enumeration_type:
548 if (area_size != -1 && type->byte_size != area_size)
550 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
553 case DW_TAG_const_type:
554 case DW_TAG_volatile_type:
555 return heap_area_differ_with_type(state, real_area1, real_area2, snapshot1, snapshot2, previous, type->subtype,
556 area_size, check_ignore, pointer_level);
558 case DW_TAG_array_type:
559 subtype = type->subtype;
560 switch (subtype->type) {
561 case DW_TAG_unspecified_type:
564 case DW_TAG_base_type:
565 case DW_TAG_enumeration_type:
566 case DW_TAG_pointer_type:
567 case DW_TAG_reference_type:
568 case DW_TAG_rvalue_reference_type:
569 case DW_TAG_structure_type:
570 case DW_TAG_class_type:
571 case DW_TAG_union_type:
572 if (subtype->full_type)
573 subtype = subtype->full_type;
574 elm_size = subtype->byte_size;
576 // TODO, just remove the type indirection?
577 case DW_TAG_const_type:
579 case DW_TAG_volatile_type:
580 subsubtype = subtype->subtype;
581 if (subsubtype->full_type)
582 subsubtype = subsubtype->full_type;
583 elm_size = subsubtype->byte_size;
588 for (int i = 0; i < type->element_count; i++) {
589 // TODO, add support for variable stride (DW_AT_byte_stride)
590 if (heap_area_differ_with_type(state, (const char*)real_area1 + (i * elm_size),
591 (const char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
592 type->subtype, subtype->byte_size, check_ignore, pointer_level))
597 case DW_TAG_reference_type:
598 case DW_TAG_rvalue_reference_type:
599 case DW_TAG_pointer_type:
600 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
601 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
602 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
603 return (addr_pointed1 != addr_pointed2);
606 if (pointer_level <= 1) {
607 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
608 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
609 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2))
610 return heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, type->subtype,
613 return (addr_pointed1 != addr_pointed2);
615 for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
616 addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + i * sizeof(void*))));
617 addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + i * sizeof(void*))));
618 bool differ = snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)
619 ? heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
620 type->subtype, pointer_level)
621 : addr_pointed1 != addr_pointed2;
627 case DW_TAG_structure_type:
628 case DW_TAG_class_type:
630 type = type->full_type;
631 if (type->byte_size == 0)
633 if (area_size != -1 && type->byte_size != area_size) {
634 if (area_size <= type->byte_size || area_size % type->byte_size != 0)
636 for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
637 if (heap_area_differ_with_type(state, (const char*)real_area1 + i * type->byte_size,
638 (const char*)real_area2 + i * type->byte_size, snapshot1, snapshot2, previous,
639 type, -1, check_ignore, 0))
643 for (const simgrid::mc::Member& member : type->members) {
644 // TODO, optimize this? (for the offset case)
645 const void* real_member1 = dwarf::resolve_member(real_area1, type, &member, &snapshot1);
646 const void* real_member2 = dwarf::resolve_member(real_area2, type, &member, &snapshot2);
647 if (heap_area_differ_with_type(state, real_member1, real_member2, snapshot1, snapshot2, previous,
648 member.type, -1, check_ignore, 0))
654 case DW_TAG_union_type:
655 return heap_area_differ_without_type(state, real_area1, real_area2, snapshot1, snapshot2, previous,
656 type->byte_size, check_ignore);
663 /** Infer the type of a part of the block from the type of the block
665 * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
667 * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
669 * @param type DWARF type ID of the root address
671 * @return DWARF type ID for given offset
673 static Type* get_offset_type(void* real_base_address, Type* type, int offset, int area_size, const Snapshot& snapshot)
675 // Beginning of the block, the inferred variable type if the type of the block:
679 switch (type->type) {
680 case DW_TAG_structure_type:
681 case DW_TAG_class_type:
683 type = type->full_type;
684 if (area_size != -1 && type->byte_size != area_size) {
685 if (area_size > type->byte_size && area_size % type->byte_size == 0)
691 for (const simgrid::mc::Member& member : type->members) {
692 if (member.has_offset_location()) {
693 // We have the offset, use it directly (shortcut):
694 if (member.offset() == offset)
697 void* real_member = dwarf::resolve_member(real_base_address, type, &member, &snapshot);
698 if ((char*)real_member - (char*)real_base_address == offset)
705 /* FIXME: other cases ? */
712 * @param area1 Process address for state 1
713 * @param area2 Process address for state 2
714 * @param snapshot1 Snapshot of state 1
715 * @param snapshot2 Snapshot of state 2
716 * @param previous Pairs of blocks already compared on the current path (or nullptr)
717 * @param type_id Type of variable
718 * @param pointer_level
719 * @return true when different, false otherwise (same or unknown)
721 static bool heap_area_differ(StateComparator& state, const void* area1, const void* area2, const Snapshot& snapshot1,
722 const Snapshot& snapshot2, HeapLocationPairs* previous, Type* type, int pointer_level)
724 const simgrid::mc::RemoteSimulation& process = mc_model_checker->get_remote_simulation();
729 int check_ignore = 0;
737 Type* new_type1 = nullptr;
739 bool match_pairs = false;
741 // This is the address of std_heap->heapinfo in the application process:
742 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
744 const malloc_info* heapinfos1 = snapshot1.read(remote((const malloc_info**)heapinfo_address));
745 const malloc_info* heapinfos2 = snapshot2.read(remote((const malloc_info**)heapinfo_address));
747 malloc_info heapinfo_temp1;
748 malloc_info heapinfo_temp2;
750 simgrid::mc::HeapLocationPairs current;
751 if (previous == nullptr) {
757 block1 = ((const char*)area1 - (const char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
758 block2 = ((const char*)area2 - (const char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
760 // If either block is a stack block:
761 if (is_block_stack((int) block1) && is_block_stack((int) block2)) {
762 previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}});
764 state.match_equals(previous);
768 // If either block is not in the expected area of memory:
769 if (((const char*)area1 < (const char*)state.std_heap_copy.heapbase) ||
770 (block1 > (ssize_t)state.processStates[0].heapsize) || (block1 < 1) ||
771 ((const char*)area2 < (const char*)state.std_heap_copy.heapbase) ||
772 (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
776 // Process address of the block:
777 void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
778 void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
782 type = type->full_type;
784 // This assume that for "boring" types (volatile ...) byte_size is absent:
785 while (type->byte_size == 0 && type->subtype != nullptr)
786 type = type->subtype;
789 if (type->type == DW_TAG_pointer_type ||
790 (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
793 type_size = type->byte_size;
796 const Region* heap_region1 = MC_get_heap_region(snapshot1);
797 const Region* heap_region2 = MC_get_heap_region(snapshot2);
799 const auto* heapinfo1 =
800 static_cast<malloc_info*>(heap_region1->read(&heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info)));
801 const auto* heapinfo2 =
802 static_cast<malloc_info*>(heap_region2->read(&heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info)));
804 if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
805 && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
808 state.match_equals(previous);
812 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
815 // TODO, lookup variable type from block type as done for fragmented blocks
817 if (state.equals_to_<1>(block1, 0).valid_ && state.equals_to_<2>(block2, 0).valid_ &&
818 state.blocksEqual(block1, block2)) {
820 state.match_equals(previous);
824 if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
825 type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
826 (type->name.empty() || type->name == "struct s_smx_context")) {
828 state.match_equals(previous);
832 if (heapinfo1->busy_block.size != heapinfo2->busy_block.size ||
833 heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
836 if (not previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}}).second) {
838 state.match_equals(previous);
842 size = heapinfo1->busy_block.busy_size;
844 // Remember (basic) type inference.
845 // The current data structure only allows us to do this for the whole block.
846 if (type != nullptr && area1 == real_addr_block1)
847 state.types_<1>(block1, 0) = type;
848 if (type != nullptr && area2 == real_addr_block2)
849 state.types_<2>(block2, 0) = type;
853 state.match_equals(previous);
857 if (heapinfo1->busy_block.ignore > 0 && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
858 check_ignore = heapinfo1->busy_block.ignore;
860 } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
862 ssize_t frag1 = (ADDR2UINT(area1) % BLOCKSIZE) >> heapinfo1->type;
863 ssize_t frag2 = (ADDR2UINT(area2) % BLOCKSIZE) >> heapinfo2->type;
865 // Process address of the fragment_:
866 void* real_addr_frag1 = (char*)real_addr_block1 + (frag1 << heapinfo1->type);
867 void* real_addr_frag2 = (char*)real_addr_block2 + (frag2 << heapinfo2->type);
869 // Check the size of the fragments against the size of the type:
870 if (type_size != -1) {
871 if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
873 state.match_equals(previous);
877 if (type_size != heapinfo1->busy_frag.frag_size[frag1]
878 || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
880 state.match_equals(previous);
885 // Check if the blocks are already matched together:
886 if (state.equals_to_<1>(block1, frag1).valid_ && state.equals_to_<2>(block2, frag2).valid_ && offset1 == offset2 &&
887 state.fragmentsEqual(block1, frag1, block2, frag2)) {
889 state.match_equals(previous);
892 // Compare the size of both fragments:
893 if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
894 if (type_size == -1) {
896 state.match_equals(previous);
902 // Size of the fragment_:
903 size = heapinfo1->busy_frag.frag_size[frag1];
905 // Remember (basic) type inference.
906 // The current data structure only allows us to do this for the whole fragment_.
907 if (type != nullptr && area1 == real_addr_frag1)
908 state.types_<1>(block1, frag1) = type;
909 if (type != nullptr && area2 == real_addr_frag2)
910 state.types_<2>(block2, frag2) = type;
912 // The type of the variable is already known:
916 // Type inference from the block type.
917 else if (state.types_<1>(block1, frag1) != nullptr || state.types_<2>(block2, frag2) != nullptr) {
918 Type* new_type2 = nullptr;
920 offset1 = (const char*)area1 - (const char*)real_addr_frag1;
921 offset2 = (const char*)area2 - (const char*)real_addr_frag2;
923 if (state.types_<1>(block1, frag1) != nullptr && state.types_<2>(block2, frag2) != nullptr) {
924 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
925 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset1, size, snapshot2);
926 } else if (state.types_<1>(block1, frag1) != nullptr) {
927 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
928 new_type2 = get_offset_type(real_addr_frag2, state.types_<1>(block1, frag1), offset2, size, snapshot2);
929 } else if (state.types_<2>(block2, frag2) != nullptr) {
930 new_type1 = get_offset_type(real_addr_frag1, state.types_<2>(block2, frag2), offset1, size, snapshot1);
931 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset2, size, snapshot2);
934 state.match_equals(previous);
938 if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
940 while (type->byte_size == 0 && type->subtype != nullptr)
941 type = type->subtype;
942 new_size1 = type->byte_size;
945 while (type->byte_size == 0 && type->subtype != nullptr)
946 type = type->subtype;
947 new_size2 = type->byte_size;
951 state.match_equals(previous);
956 if (new_size1 > 0 && new_size1 == new_size2) {
961 if (offset1 == 0 && offset2 == 0 &&
962 not previous->insert(HeapLocationPair{{HeapLocation(block1, frag1), HeapLocation(block2, frag2)}}).second) {
964 state.match_equals(previous);
970 state.match_equals(previous);
974 if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
975 (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
976 check_ignore = heapinfo1->busy_frag.ignore[frag1];
980 /* Start comparison */
982 type ? heap_area_differ_with_type(state, area1, area2, snapshot1, snapshot2, previous, type, size, check_ignore,
984 : heap_area_differ_without_type(state, area1, area2, snapshot1, snapshot2, previous, size, check_ignore);
989 state.match_equals(previous);
993 } // namespace simgrid
995 /************************** Snapshot comparison *******************************/
996 /******************************************************************************/
998 static bool areas_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
999 const simgrid::mc::Snapshot& snapshot1, simgrid::mc::Region* region1,
1000 const void* real_area2, const simgrid::mc::Snapshot& snapshot2,
1001 simgrid::mc::Region* region2, const simgrid::mc::Type* type, int pointer_level)
1003 const simgrid::mc::Type* subtype;
1004 const simgrid::mc::Type* subsubtype;
1007 xbt_assert(type != nullptr);
1008 switch (type->type) {
1009 case DW_TAG_unspecified_type:
1012 case DW_TAG_base_type:
1013 case DW_TAG_enumeration_type:
1014 case DW_TAG_union_type:
1015 return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
1016 case DW_TAG_typedef:
1017 case DW_TAG_volatile_type:
1018 case DW_TAG_const_type:
1019 return areas_differ_with_type(state, real_area1, snapshot1, region1, real_area2, snapshot2, region2,
1020 type->subtype, pointer_level);
1021 case DW_TAG_array_type:
1022 subtype = type->subtype;
1023 switch (subtype->type) {
1024 case DW_TAG_unspecified_type:
1027 case DW_TAG_base_type:
1028 case DW_TAG_enumeration_type:
1029 case DW_TAG_pointer_type:
1030 case DW_TAG_reference_type:
1031 case DW_TAG_rvalue_reference_type:
1032 case DW_TAG_structure_type:
1033 case DW_TAG_class_type:
1034 case DW_TAG_union_type:
1035 if (subtype->full_type)
1036 subtype = subtype->full_type;
1037 elm_size = subtype->byte_size;
1039 case DW_TAG_const_type:
1040 case DW_TAG_typedef:
1041 case DW_TAG_volatile_type:
1042 subsubtype = subtype->subtype;
1043 if (subsubtype->full_type)
1044 subsubtype = subsubtype->full_type;
1045 elm_size = subsubtype->byte_size;
1050 for (int i = 0; i < type->element_count; i++) {
1051 size_t off = i * elm_size;
1052 if (areas_differ_with_type(state, (const char*)real_area1 + off, snapshot1, region1,
1053 (const char*)real_area2 + off, snapshot2, region2, type->subtype, pointer_level))
1057 case DW_TAG_pointer_type:
1058 case DW_TAG_reference_type:
1059 case DW_TAG_rvalue_reference_type: {
1060 const void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
1061 const void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
1063 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
1064 return (addr_pointed1 != addr_pointed2);
1065 if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
1067 if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
1069 if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
1074 // Some cases are not handled here:
1075 // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
1076 // * a pointer leads to the read-only segment of the current object
1077 // * a pointer lead to a different ELF object
1079 if (snapshot1.on_heap(addr_pointed1)) {
1080 if (not snapshot2.on_heap(addr_pointed2))
1082 // The pointers are both in the heap:
1083 return simgrid::mc::heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, nullptr,
1084 type->subtype, pointer_level);
1086 } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
1087 // The pointers are both in the current object R/W segment:
1088 if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
1090 if (not type->type_id)
1091 return (addr_pointed1 != addr_pointed2);
1093 return areas_differ_with_type(state, addr_pointed1, snapshot1, region1, addr_pointed2, snapshot2, region2,
1094 type->subtype, pointer_level);
1096 // TODO, We do not handle very well the case where
1097 // it belongs to a different (non-heap) region from the current one.
1099 return (addr_pointed1 != addr_pointed2);
1102 case DW_TAG_structure_type:
1103 case DW_TAG_class_type:
1104 for (const simgrid::mc::Member& member : type->members) {
1105 const void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
1106 const void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
1107 simgrid::mc::Region* subregion1 = snapshot1.get_region(member1, region1); // region1 is hinted
1108 simgrid::mc::Region* subregion2 = snapshot2.get_region(member2, region2); // region2 is hinted
1109 if (areas_differ_with_type(state, member1, snapshot1, subregion1, member2, snapshot2, subregion2, member.type,
1114 case DW_TAG_subroutine_type:
1117 XBT_VERB("Unknown case: %d", type->type);
1124 static bool global_variables_differ(simgrid::mc::StateComparator& state,
1125 const simgrid::mc::ObjectInformation* object_info, simgrid::mc::Region* r1,
1126 simgrid::mc::Region* r2, const simgrid::mc::Snapshot& snapshot1,
1127 const simgrid::mc::Snapshot& snapshot2)
1129 xbt_assert(r1 && r2, "Missing region.");
1131 const std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
1133 for (simgrid::mc::Variable const& current_var : variables) {
1134 // If the variable is not in this object, skip it:
1135 // We do not expect to find a pointer to something which is not reachable
1136 // by the global variables.
1137 if ((char*)current_var.address < object_info->start_rw || (char*)current_var.address > object_info->end_rw)
1140 const simgrid::mc::Type* bvariable_type = current_var.type;
1141 if (areas_differ_with_type(state, current_var.address, snapshot1, r1, current_var.address, snapshot2, r2,
1142 bvariable_type, 0)) {
1143 XBT_VERB("Global variable %s (%p) is different between snapshots", current_var.name.c_str(), current_var.address);
1151 static bool local_variables_differ(simgrid::mc::StateComparator& state, const simgrid::mc::Snapshot& snapshot1,
1152 const simgrid::mc::Snapshot& snapshot2, const_mc_snapshot_stack_t stack1,
1153 const_mc_snapshot_stack_t stack2)
1155 if (stack1->local_variables.size() != stack2->local_variables.size()) {
1156 XBT_VERB("Different number of local variables");
1160 for (unsigned int cursor = 0; cursor < stack1->local_variables.size(); cursor++) {
1161 const_local_variable_t current_var1 = &stack1->local_variables[cursor];
1162 const_local_variable_t current_var2 = &stack2->local_variables[cursor];
1163 if (current_var1->name != current_var2->name || current_var1->subprogram != current_var2->subprogram ||
1164 current_var1->ip != current_var2->ip) {
1165 // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
1166 XBT_VERB("Different name of variable (%s - %s) or frame (%s - %s) or ip (%lu - %lu)", current_var1->name.c_str(),
1167 current_var2->name.c_str(), current_var1->subprogram->name.c_str(),
1168 current_var2->subprogram->name.c_str(), current_var1->ip, current_var2->ip);
1172 if (areas_differ_with_type(state, current_var1->address, snapshot1, snapshot1.get_region(current_var1->address),
1173 current_var2->address, snapshot2, snapshot2.get_region(current_var2->address),
1174 current_var1->type, 0)) {
1175 XBT_VERB("Local variable %s (%p - %p) in frame %s is different between snapshots", current_var1->name.c_str(),
1176 current_var1->address, current_var2->address, current_var1->subprogram->name.c_str());
1186 bool snapshot_equal(const Snapshot* s1, const Snapshot* s2)
1188 // TODO, make this a field of ModelChecker or something similar
1189 static StateComparator state_comparator;
1191 const RemoteSimulation& process = mc_model_checker->get_remote_simulation();
1193 if (s1->hash_ != s2->hash_) {
1194 XBT_VERB("(%d - %d) Different hash: 0x%" PRIx64 "--0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_,
1198 XBT_VERB("(%d - %d) Same hash: 0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_);
1200 /* Compare enabled processes */
1201 if (s1->enabled_processes_ != s2->enabled_processes_) {
1202 XBT_VERB("(%d - %d) Different amount of enabled processes", s1->num_state_, s2->num_state_);
1206 /* Compare size of stacks */
1207 for (unsigned long i = 0; i < s1->stacks_.size(); i++) {
1208 size_t size_used1 = s1->stack_sizes_[i];
1209 size_t size_used2 = s2->stack_sizes_[i];
1210 if (size_used1 != size_used2) {
1211 XBT_VERB("(%d - %d) Different size used in stacks: %zu - %zu", s1->num_state_, s2->num_state_, size_used1,
1217 /* Init heap information used in heap comparison algorithm */
1218 const s_xbt_mheap_t* heap1 = static_cast<xbt_mheap_t>(s1->read_bytes(
1219 alloca(sizeof(s_xbt_mheap_t)), sizeof(s_xbt_mheap_t), remote(process.heap_address), ReadOptions::lazy()));
1220 const s_xbt_mheap_t* heap2 = static_cast<xbt_mheap_t>(s2->read_bytes(
1221 alloca(sizeof(s_xbt_mheap_t)), sizeof(s_xbt_mheap_t), remote(process.heap_address), ReadOptions::lazy()));
1222 if (state_comparator.initHeapInformation(heap1, heap2, s1->to_ignore_, s2->to_ignore_) == -1) {
1223 XBT_VERB("(%d - %d) Different heap information", s1->num_state_, s2->num_state_);
1227 /* Stacks comparison */
1228 for (unsigned int cursor = 0; cursor < s1->stacks_.size(); cursor++) {
1229 const_mc_snapshot_stack_t stack1 = &s1->stacks_[cursor];
1230 const_mc_snapshot_stack_t stack2 = &s2->stacks_[cursor];
1232 if (local_variables_differ(state_comparator, *s1, *s2, stack1, stack2)) {
1233 XBT_VERB("(%d - %d) Different local variables between stacks %u", s1->num_state_, s2->num_state_, cursor + 1);
1238 size_t regions_count = s1->snapshot_regions_.size();
1239 if (regions_count != s2->snapshot_regions_.size())
1242 for (size_t k = 0; k != regions_count; ++k) {
1243 Region* region1 = s1->snapshot_regions_[k].get();
1244 Region* region2 = s2->snapshot_regions_[k].get();
1247 if (region1->region_type() != RegionType::Data)
1250 xbt_assert(region1->region_type() == region2->region_type());
1251 xbt_assert(region1->object_info() == region2->object_info());
1252 xbt_assert(region1->object_info());
1254 /* Compare global variables */
1255 if (global_variables_differ(state_comparator, region1->object_info(), region1, region2, *s1, *s2)) {
1256 std::string const& name = region1->object_info()->file_name;
1257 XBT_VERB("(%d - %d) Different global variables in %s", s1->num_state_, s2->num_state_, name.c_str());
1263 if (mmalloc_heap_differ(state_comparator, *s1, *s2)) {
1264 XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", s1->num_state_, s2->num_state_);
1268 XBT_VERB("(%d - %d) No difference found", s1->num_state_, s2->num_state_);
1273 } // namespace simgrid