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 snapshooting 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 if (heapinfo1->type < 0) {
258 fprintf(stderr, "Unkown mmalloc block type.\n");
262 void* addr_block1 = ((void*)(((ADDR2UINT(i1)) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase));
264 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
266 if (is_stack(addr_block1)) {
267 for (size_t k = 0; k < heapinfo1->busy_block.size; k++)
268 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
269 for (size_t k = 0; k < heapinfo2->busy_block.size; k++)
270 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
271 i1 += heapinfo1->busy_block.size;
275 if (state.equals_to_<1>(i1, 0).valid_) {
283 /* Try first to associate to same block in the other heap */
284 if (heapinfo2->type == heapinfo1->type && state.equals_to_<2>(i1, 0).valid_ == 0) {
285 void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
286 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
287 for (size_t k = 1; k < heapinfo2->busy_block.size; k++)
288 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
289 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
290 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
292 i1 += heapinfo1->busy_block.size;
296 while (i2 < state.heaplimit && not equal) {
298 void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
305 const malloc_info* heapinfo2b =
306 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
308 if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
313 if (state.equals_to_<2>(i2, 0).valid_) {
318 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
319 for (size_t k = 1; k < heapinfo2b->busy_block.size; k++)
320 state.equals_to_<2>(i2 + k, 0) = HeapArea(i1, -1);
321 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
322 state.equals_to_<1>(i1 + k, 0) = HeapArea(i2, -1);
324 i1 += heapinfo1->busy_block.size;
331 XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
335 } else { /* Fragmented block */
337 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 = (void*)((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 void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
353 void* addr_frag2 = (void*)((char*)addr_block2 + (j1 << heapinfo2->type));
354 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0))
358 while (i2 < state.heaplimit && not equal) {
360 const malloc_info* heapinfo2b =
361 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
363 if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
368 // We currently do not match fragments with unfragmented blocks (maybe we should).
369 if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
374 if (heapinfo2b->type < 0) {
375 fprintf(stderr, "Unknown mmalloc block type.\n");
379 for (size_t j2 = 0; j2 < (size_t)(BLOCKSIZE >> heapinfo2b->type); j2++) {
381 if (i2 == i1 && j2 == j1)
384 if (state.equals_to_<2>(i2, j2).valid_)
387 void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
388 void* addr_frag2 = (void*)((char*)addr_block2 + (j2 << heapinfo2b->type));
390 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
400 XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
401 heapinfo1->busy_frag.frag_size[j1], addr_frag1);
410 /* All blocks/fragments are equal to another block/fragment_ ? */
411 for (size_t i = 1; i < state.heaplimit; i++) {
412 const malloc_info* heapinfo1 =
413 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[i], sizeof(malloc_info));
415 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo1->busy_block.busy_size > 0 &&
416 not state.equals_to_<1>(i, 0).valid_) {
417 XBT_DEBUG("Block %zu not found (size used = %zu)", i, heapinfo1->busy_block.busy_size);
421 if (heapinfo1->type <= 0)
423 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo1->type); j++)
424 if (i1 == state.heaplimit && heapinfo1->busy_frag.frag_size[j] > 0 && not state.equals_to_<1>(i, j).valid_) {
425 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)", i, j, heapinfo1->busy_frag.frag_size[j]);
430 for (size_t i = 1; i < state.heaplimit; i++) {
431 const malloc_info* heapinfo2 =
432 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[i], sizeof(malloc_info));
433 if (heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo2->busy_block.busy_size > 0 &&
434 not state.equals_to_<2>(i, 0).valid_) {
435 XBT_DEBUG("Block %zu not found (size used = %zu)", i,
436 heapinfo2->busy_block.busy_size);
440 if (heapinfo2->type <= 0)
443 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo2->type); j++)
444 if (i1 == state.heaplimit && heapinfo2->busy_frag.frag_size[j] > 0 && not state.equals_to_<2>(i, j).valid_) {
445 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)",
446 i, j, heapinfo2->busy_frag.frag_size[j]);
457 * @param real_area1 Process address for state 1
458 * @param real_area2 Process address for state 2
459 * @param snapshot1 Snapshot of state 1
460 * @param snapshot2 Snapshot of state 2
463 * @param check_ignore
464 * @return true when different, false otherwise (same or unknown)
466 static bool heap_area_differ_without_type(simgrid::mc::StateComparator& state, const void* real_area1,
467 const void* real_area2, const simgrid::mc::Snapshot& snapshot1,
468 const simgrid::mc::Snapshot& snapshot2, HeapLocationPairs* previous, int size,
471 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
472 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
473 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
475 for (int i = 0; i < size; ) {
477 if (check_ignore > 0) {
478 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, (const char*)real_area1 + i);
480 ssize_t ignore2 = heap_comparison_ignore_size(state.processStates[1].to_ignore, (const char*)real_area2 + i);
481 if (ignore2 == ignore1) {
494 if (MC_snapshot_region_memcmp((const char*)real_area1 + i, heap_region1, (const char*)real_area2 + i, heap_region2,
497 int pointer_align = (i / sizeof(void *)) * sizeof(void *);
498 const void* addr_pointed1 = snapshot1.read(remote((void**)((const char*)real_area1 + pointer_align)));
499 const void* addr_pointed2 = snapshot2.read(remote((void**)((const char*)real_area2 + pointer_align)));
501 if (process.in_maestro_stack(remote(addr_pointed1)) && process.in_maestro_stack(remote(addr_pointed2))) {
502 i = pointer_align + sizeof(void *);
506 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)) {
507 // Both addresses are in the heap:
508 if (heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, nullptr, 0))
510 i = pointer_align + sizeof(void *);
526 * @param real_area1 Process address for state 1
527 * @param real_area2 Process address for state 2
528 * @param snapshot1 Snapshot of state 1
529 * @param snapshot2 Snapshot of state 2
532 * @param area_size either a byte_size or an elements_count (?)
533 * @param check_ignore
534 * @param pointer_level
535 * @return true when different, false otherwise (same or unknown)
537 static bool heap_area_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
538 const void* real_area2, const simgrid::mc::Snapshot& snapshot1,
539 const simgrid::mc::Snapshot& snapshot2, HeapLocationPairs* previous,
540 simgrid::mc::Type* type, int area_size, int check_ignore, int pointer_level)
542 // HACK: This should not happen but in pratice, there are some
543 // DW_TAG_typedef without an associated DW_AT_type:
544 //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
545 // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
546 // <538837> DW_AT_decl_file : 98
547 // <538838> DW_AT_decl_line : 37
551 if (is_stack(real_area1) && is_stack(real_area2))
554 if (check_ignore > 0) {
555 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
556 if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
560 simgrid::mc::Type* subtype;
561 simgrid::mc::Type* subsubtype;
563 const void* addr_pointed1;
564 const void* addr_pointed2;
566 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
567 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
569 switch (type->type) {
570 case DW_TAG_unspecified_type:
573 case DW_TAG_base_type:
574 if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
575 if (real_area1 == real_area2)
578 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
580 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_enumeration_type:
587 if (area_size != -1 && type->byte_size != area_size)
589 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
592 case DW_TAG_const_type:
593 case DW_TAG_volatile_type:
594 return heap_area_differ_with_type(state, real_area1, real_area2, snapshot1, snapshot2, previous, type->subtype,
595 area_size, check_ignore, pointer_level);
597 case DW_TAG_array_type:
598 subtype = type->subtype;
599 switch (subtype->type) {
600 case DW_TAG_unspecified_type:
603 case DW_TAG_base_type:
604 case DW_TAG_enumeration_type:
605 case DW_TAG_pointer_type:
606 case DW_TAG_reference_type:
607 case DW_TAG_rvalue_reference_type:
608 case DW_TAG_structure_type:
609 case DW_TAG_class_type:
610 case DW_TAG_union_type:
611 if (subtype->full_type)
612 subtype = subtype->full_type;
613 elm_size = subtype->byte_size;
615 // TODO, just remove the type indirection?
616 case DW_TAG_const_type:
618 case DW_TAG_volatile_type:
619 subsubtype = subtype->subtype;
620 if (subsubtype->full_type)
621 subsubtype = subsubtype->full_type;
622 elm_size = subsubtype->byte_size;
627 for (int i = 0; i < type->element_count; i++) {
628 // TODO, add support for variable stride (DW_AT_byte_stride)
629 if (heap_area_differ_with_type(state, (const char*)real_area1 + (i * elm_size),
630 (const char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
631 type->subtype, subtype->byte_size, check_ignore, pointer_level))
636 case DW_TAG_reference_type:
637 case DW_TAG_rvalue_reference_type:
638 case DW_TAG_pointer_type:
639 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
640 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
641 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
642 return (addr_pointed1 != addr_pointed2);
645 if (pointer_level <= 1) {
646 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
647 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
648 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2))
649 return heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, type->subtype,
652 return (addr_pointed1 != addr_pointed2);
654 for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
655 addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + i * sizeof(void*))));
656 addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + i * sizeof(void*))));
657 bool differ = snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)
658 ? heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
659 type->subtype, pointer_level)
660 : addr_pointed1 != addr_pointed2;
666 case DW_TAG_structure_type:
667 case DW_TAG_class_type:
669 type = type->full_type;
670 if (area_size != -1 && type->byte_size != area_size) {
671 if (area_size <= type->byte_size || area_size % type->byte_size != 0)
673 for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
674 if (heap_area_differ_with_type(state, (const char*)real_area1 + i * type->byte_size,
675 (const char*)real_area2 + i * type->byte_size, snapshot1, snapshot2, previous,
676 type, -1, check_ignore, 0))
680 for (simgrid::mc::Member& member : type->members) {
681 // TODO, optimize this? (for the offset case)
682 void* real_member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
683 void* real_member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
684 if (heap_area_differ_with_type(state, real_member1, real_member2, snapshot1, snapshot2, previous,
685 member.type, -1, check_ignore, 0))
691 case DW_TAG_union_type:
692 return heap_area_differ_without_type(state, real_area1, real_area2, snapshot1, snapshot2, previous,
693 type->byte_size, check_ignore);
701 /** Infer the type of a part of the block from the type of the block
703 * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
705 * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
707 * @param type DWARF type ID of the root address
709 * @return DWARF type ID for given offset
711 static simgrid::mc::Type* get_offset_type(void* real_base_address, simgrid::mc::Type* type, int offset, int area_size,
712 const simgrid::mc::Snapshot& snapshot)
715 // Beginning of the block, the infered variable type if the type of the block:
719 switch (type->type) {
721 case DW_TAG_structure_type:
722 case DW_TAG_class_type:
724 type = type->full_type;
725 if (area_size != -1 && type->byte_size != area_size) {
726 if (area_size > type->byte_size && area_size % type->byte_size == 0)
732 for (simgrid::mc::Member& member : type->members) {
733 if (member.has_offset_location()) {
734 // We have the offset, use it directly (shortcut):
735 if (member.offset() == offset)
738 void* real_member = simgrid::dwarf::resolve_member(real_base_address, type, &member, &snapshot);
739 if ((char*)real_member - (char*)real_base_address == offset)
746 /* FIXME: other cases ? */
754 * @param area1 Process address for state 1
755 * @param area2 Process address for state 2
756 * @param snapshot1 Snapshot of state 1
757 * @param snapshot2 Snapshot of state 2
758 * @param previous Pairs of blocks already compared on the current path (or nullptr)
759 * @param type_id Type of variable
760 * @param pointer_level
761 * @return true when different, false otherwise (same or unknown)
763 static bool heap_area_differ(simgrid::mc::StateComparator& state, const void* area1, const void* area2,
764 const simgrid::mc::Snapshot& snapshot1, const simgrid::mc::Snapshot& snapshot2,
765 HeapLocationPairs* previous, simgrid::mc::Type* type, int pointer_level)
767 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
772 int check_ignore = 0;
780 simgrid::mc::Type* new_type1 = nullptr;
781 simgrid::mc::Type* new_type2 = nullptr;
783 bool match_pairs = false;
785 // This is the address of std_heap->heapinfo in the application process:
786 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
788 const malloc_info* heapinfos1 = snapshot1.read(remote((const malloc_info**)heapinfo_address));
789 const malloc_info* heapinfos2 = snapshot2.read(remote((const malloc_info**)heapinfo_address));
791 malloc_info heapinfo_temp1;
792 malloc_info heapinfo_temp2;
794 simgrid::mc::HeapLocationPairs current;
795 if (previous == nullptr) {
801 block1 = ((char*)area1 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
802 block2 = ((char*)area2 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
804 // If either block is a stack block:
805 if (is_block_stack((int) block1) && is_block_stack((int) block2)) {
806 previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}});
808 state.match_equals(previous);
812 // If either block is not in the expected area of memory:
813 if (((char*)area1 < (char*)state.std_heap_copy.heapbase) || (block1 > (ssize_t)state.processStates[0].heapsize) ||
814 (block1 < 1) || ((char*)area2 < (char*)state.std_heap_copy.heapbase) ||
815 (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
819 // Process address of the block:
820 void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
821 void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
825 type = type->full_type;
827 // This assume that for "boring" types (volatile ...) byte_size is absent:
828 while (type->byte_size == 0 && type->subtype != nullptr)
829 type = type->subtype;
832 if (type->type == DW_TAG_pointer_type ||
833 (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
836 type_size = type->byte_size;
840 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
841 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
843 const malloc_info* heapinfo1 =
844 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info));
845 const malloc_info* heapinfo2 =
846 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info));
848 if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
849 && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
852 state.match_equals(previous);
856 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
859 // TODO, lookup variable type from block type as done for fragmented blocks
861 if (state.equals_to_<1>(block1, 0).valid_ && state.equals_to_<2>(block2, 0).valid_ &&
862 state.blocksEqual(block1, block2)) {
864 state.match_equals(previous);
868 if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
869 type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
870 (type->name.empty() || type->name == "struct s_smx_context")) {
872 state.match_equals(previous);
876 if (heapinfo1->busy_block.size != heapinfo2->busy_block.size ||
877 heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
880 if (not previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}}).second) {
882 state.match_equals(previous);
886 size = heapinfo1->busy_block.busy_size;
888 // Remember (basic) type inference.
889 // The current data structure only allows us to do this for the whole block.
890 if (type != nullptr && area1 == real_addr_block1)
891 state.types_<1>(block1, 0) = type;
892 if (type != nullptr && area2 == real_addr_block2)
893 state.types_<2>(block2, 0) = type;
897 state.match_equals(previous);
901 if (heapinfo1->busy_block.ignore > 0
902 && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
903 check_ignore = heapinfo1->busy_block.ignore;
905 } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
908 ssize_t frag1 = ((uintptr_t)(ADDR2UINT(area1) % (BLOCKSIZE))) >> heapinfo1->type;
909 ssize_t frag2 = ((uintptr_t)(ADDR2UINT(area2) % (BLOCKSIZE))) >> heapinfo2->type;
911 // Process address of the fragment_:
912 void* real_addr_frag1 = (void*)((char*)real_addr_block1 + (frag1 << heapinfo1->type));
913 void* real_addr_frag2 = (void*)((char*)real_addr_block2 + (frag2 << heapinfo2->type));
915 // Check the size of the fragments against the size of the type:
916 if (type_size != -1) {
917 if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
919 state.match_equals(previous);
923 if (type_size != heapinfo1->busy_frag.frag_size[frag1]
924 || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
926 state.match_equals(previous);
931 // Check if the blocks are already matched together:
932 if (state.equals_to_<1>(block1, frag1).valid_ && state.equals_to_<2>(block2, frag2).valid_ && offset1 == offset2 &&
933 state.fragmentsEqual(block1, frag1, block2, frag2)) {
935 state.match_equals(previous);
938 // Compare the size of both fragments:
939 if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
940 if (type_size == -1) {
942 state.match_equals(previous);
948 // Size of the fragment_:
949 size = heapinfo1->busy_frag.frag_size[frag1];
951 // Remember (basic) type inference.
952 // The current data structure only allows us to do this for the whole fragment_.
953 if (type != nullptr && area1 == real_addr_frag1)
954 state.types_<1>(block1, frag1) = type;
955 if (type != nullptr && area2 == real_addr_frag2)
956 state.types_<2>(block2, frag2) = type;
958 // The type of the variable is already known:
960 new_type1 = new_type2 = type;
962 // Type inference from the block type.
963 else if (state.types_<1>(block1, frag1) != nullptr || state.types_<2>(block2, frag2) != nullptr) {
965 offset1 = (char*)area1 - (char*)real_addr_frag1;
966 offset2 = (char*)area2 - (char*)real_addr_frag2;
968 if (state.types_<1>(block1, frag1) != nullptr && state.types_<2>(block2, frag2) != nullptr) {
969 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
970 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset1, size, snapshot2);
971 } else if (state.types_<1>(block1, frag1) != nullptr) {
972 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
973 new_type2 = get_offset_type(real_addr_frag2, state.types_<1>(block1, frag1), offset2, size, snapshot2);
974 } else if (state.types_<2>(block2, frag2) != nullptr) {
975 new_type1 = get_offset_type(real_addr_frag1, state.types_<2>(block2, frag2), offset1, size, snapshot1);
976 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset2, size, snapshot2);
979 state.match_equals(previous);
983 if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
986 while (type->byte_size == 0 && type->subtype != nullptr)
987 type = type->subtype;
988 new_size1 = type->byte_size;
991 while (type->byte_size == 0 && type->subtype != nullptr)
992 type = type->subtype;
993 new_size2 = type->byte_size;
997 state.match_equals(previous);
1002 if (new_size1 > 0 && new_size1 == new_size2) {
1007 if (offset1 == 0 && offset2 == 0 &&
1008 not previous->insert(HeapLocationPair{{HeapLocation(block1, frag1), HeapLocation(block2, frag2)}}).second) {
1010 state.match_equals(previous);
1016 state.match_equals(previous);
1020 if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
1021 (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
1022 check_ignore = heapinfo1->busy_frag.ignore[frag1];
1027 /* Start comparison */
1029 type ? heap_area_differ_with_type(state, area1, area2, snapshot1, snapshot2, previous, type, size, check_ignore,
1031 : heap_area_differ_without_type(state, area1, area2, snapshot1, snapshot2, previous, size, check_ignore);
1036 state.match_equals(previous);
1043 /************************** Snapshot comparison *******************************/
1044 /******************************************************************************/
1046 static bool areas_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
1047 const simgrid::mc::Snapshot& snapshot1, simgrid::mc::Region* region1,
1048 const void* real_area2, const simgrid::mc::Snapshot& snapshot2,
1049 simgrid::mc::Region* region2, simgrid::mc::Type* type, int pointer_level)
1051 simgrid::mc::Type* subtype;
1052 simgrid::mc::Type* subsubtype;
1056 xbt_assert(type != nullptr);
1057 switch (type->type) {
1058 case DW_TAG_unspecified_type:
1061 case DW_TAG_base_type:
1062 case DW_TAG_enumeration_type:
1063 case DW_TAG_union_type:
1064 return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
1065 case DW_TAG_typedef:
1066 case DW_TAG_volatile_type:
1067 case DW_TAG_const_type:
1068 return areas_differ_with_type(state, real_area1, snapshot1, region1, real_area2, snapshot2, region2,
1069 type->subtype, pointer_level);
1070 case DW_TAG_array_type:
1071 subtype = type->subtype;
1072 switch (subtype->type) {
1073 case DW_TAG_unspecified_type:
1076 case DW_TAG_base_type:
1077 case DW_TAG_enumeration_type:
1078 case DW_TAG_pointer_type:
1079 case DW_TAG_reference_type:
1080 case DW_TAG_rvalue_reference_type:
1081 case DW_TAG_structure_type:
1082 case DW_TAG_class_type:
1083 case DW_TAG_union_type:
1084 if (subtype->full_type)
1085 subtype = subtype->full_type;
1086 elm_size = subtype->byte_size;
1088 case DW_TAG_const_type:
1089 case DW_TAG_typedef:
1090 case DW_TAG_volatile_type:
1091 subsubtype = subtype->subtype;
1092 if (subsubtype->full_type)
1093 subsubtype = subsubtype->full_type;
1094 elm_size = subsubtype->byte_size;
1099 for (i = 0; i < type->element_count; i++) {
1100 size_t off = i * elm_size;
1101 if (areas_differ_with_type(state, (char*)real_area1 + off, snapshot1, region1, (char*)real_area2 + off,
1102 snapshot2, region2, type->subtype, pointer_level))
1106 case DW_TAG_pointer_type:
1107 case DW_TAG_reference_type:
1108 case DW_TAG_rvalue_reference_type: {
1109 const void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
1110 const void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
1112 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
1113 return (addr_pointed1 != addr_pointed2);
1114 if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
1116 if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
1118 if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
1123 // Some cases are not handled here:
1124 // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
1125 // * a pointer leads to the read-only segment of the current object
1126 // * a pointer lead to a different ELF object
1128 if (snapshot1.on_heap(addr_pointed1)) {
1129 if (not snapshot2.on_heap(addr_pointed2))
1131 // The pointers are both in the heap:
1132 return simgrid::mc::heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, nullptr,
1133 type->subtype, pointer_level);
1135 } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
1136 // The pointers are both in the current object R/W segment:
1137 if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
1139 if (not type->type_id)
1140 return (addr_pointed1 != addr_pointed2);
1142 return areas_differ_with_type(state, addr_pointed1, snapshot1, region1, addr_pointed2, snapshot2, region2,
1143 type->subtype, pointer_level);
1146 // TODO, We do not handle very well the case where
1147 // it belongs to a different (non-heap) region from the current one.
1149 return (addr_pointed1 != addr_pointed2);
1152 case DW_TAG_structure_type:
1153 case DW_TAG_class_type:
1154 for (simgrid::mc::Member& member : type->members) {
1155 void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
1156 void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
1157 simgrid::mc::Region* subregion1 = snapshot1.get_region(member1, region1); // region1 is hinted
1158 simgrid::mc::Region* subregion2 = snapshot2.get_region(member2, region2); // region2 is hinted
1159 if (areas_differ_with_type(state, member1, snapshot1, subregion1, member2, snapshot2, subregion2, member.type,
1164 case DW_TAG_subroutine_type:
1167 XBT_VERB("Unknown case: %d", type->type);
1174 static bool global_variables_differ(simgrid::mc::StateComparator& state, simgrid::mc::ObjectInformation* object_info,
1175 simgrid::mc::Region* r1, simgrid::mc::Region* r2,
1176 const simgrid::mc::Snapshot& snapshot1, const simgrid::mc::Snapshot& snapshot2)
1178 xbt_assert(r1 && r2, "Missing region.");
1180 const std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
1182 for (simgrid::mc::Variable const& current_var : variables) {
1184 // If the variable is not in this object, skip it:
1185 // We do not expect to find a pointer to something which is not reachable
1186 // by the global variables.
1187 if ((char *) current_var.address < (char *) object_info->start_rw
1188 || (char *) current_var.address > (char *) object_info->end_rw)
1191 simgrid::mc::Type* bvariable_type = current_var.type;
1192 if (areas_differ_with_type(state, current_var.address, snapshot1, r1, current_var.address, snapshot2, r2,
1193 bvariable_type, 0)) {
1194 XBT_VERB("Global variable %s (%p) is different between snapshots", current_var.name.c_str(), current_var.address);
1202 static bool local_variables_differ(simgrid::mc::StateComparator& state, const simgrid::mc::Snapshot& snapshot1,
1203 const simgrid::mc::Snapshot& snapshot2, const_mc_snapshot_stack_t stack1,
1204 const_mc_snapshot_stack_t stack2)
1206 if (stack1->local_variables.size() != stack2->local_variables.size()) {
1207 XBT_VERB("Different number of local variables");
1211 for (unsigned int cursor = 0; cursor < stack1->local_variables.size(); cursor++) {
1212 const_local_variable_t current_var1 = &stack1->local_variables[cursor];
1213 const_local_variable_t current_var2 = &stack2->local_variables[cursor];
1214 if (current_var1->name != current_var2->name || current_var1->subprogram != current_var2->subprogram ||
1215 current_var1->ip != current_var2->ip) {
1216 // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
1217 XBT_VERB("Different name of variable (%s - %s) or frame (%s - %s) or ip (%lu - %lu)", current_var1->name.c_str(),
1218 current_var2->name.c_str(), current_var1->subprogram->name.c_str(),
1219 current_var2->subprogram->name.c_str(), current_var1->ip, current_var2->ip);
1223 if (areas_differ_with_type(state, current_var1->address, snapshot1, snapshot1.get_region(current_var1->address),
1224 current_var2->address, snapshot2, snapshot2.get_region(current_var2->address),
1225 current_var1->type, 0)) {
1226 XBT_VERB("Local variable %s (%p - %p) in frame %s is different between snapshots", current_var1->name.c_str(),
1227 current_var1->address, current_var2->address, current_var1->subprogram->name.c_str());
1237 bool snapshot_equal(const Snapshot* s1, const Snapshot* s2)
1239 // TODO, make this a field of ModelChecker or something similar
1240 static StateComparator state_comparator;
1242 const RemoteClient& process = mc_model_checker->process();
1244 if (s1->hash_ != s2->hash_) {
1245 XBT_VERB("(%d - %d) Different hash: 0x%" PRIx64 "--0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_,
1249 XBT_VERB("(%d - %d) Same hash: 0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_);
1251 /* Compare enabled processes */
1252 if (s1->enabled_processes_ != s2->enabled_processes_) {
1253 XBT_VERB("(%d - %d) Different amount of enabled processes", s1->num_state_, s2->num_state_);
1257 /* Compare size of stacks */
1258 for (unsigned long i = 0; i < s1->stacks_.size(); i++) {
1259 size_t size_used1 = s1->stack_sizes_[i];
1260 size_t size_used2 = s2->stack_sizes_[i];
1261 if (size_used1 != size_used2) {
1262 XBT_VERB("(%d - %d) Different size used in stacks: %zu - %zu", s1->num_state_, s2->num_state_, size_used1,
1268 /* Init heap information used in heap comparison algorithm */
1270 static_cast<xbt_mheap_t>(s1->read_bytes(alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
1271 remote(process.heap_address), simgrid::mc::ReadOptions::lazy()));
1273 static_cast<xbt_mheap_t>(s2->read_bytes(alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
1274 remote(process.heap_address), simgrid::mc::ReadOptions::lazy()));
1275 if (state_comparator.initHeapInformation(heap1, heap2, s1->to_ignore_, s2->to_ignore_) == -1) {
1276 XBT_VERB("(%d - %d) Different heap information", s1->num_state_, s2->num_state_);
1280 /* Stacks comparison */
1281 for (unsigned int cursor = 0; cursor < s1->stacks_.size(); cursor++) {
1282 const_mc_snapshot_stack_t stack1 = &s1->stacks_[cursor];
1283 const_mc_snapshot_stack_t stack2 = &s2->stacks_[cursor];
1285 if (local_variables_differ(state_comparator, *s1, *s2, stack1, stack2)) {
1286 XBT_VERB("(%d - %d) Different local variables between stacks %u", s1->num_state_, s2->num_state_, cursor + 1);
1291 size_t regions_count = s1->snapshot_regions_.size();
1292 if (regions_count != s2->snapshot_regions_.size())
1295 for (size_t k = 0; k != regions_count; ++k) {
1296 Region* region1 = s1->snapshot_regions_[k].get();
1297 Region* region2 = s2->snapshot_regions_[k].get();
1300 if (region1->region_type() != RegionType::Data)
1303 xbt_assert(region1->region_type() == region2->region_type());
1304 xbt_assert(region1->object_info() == region2->object_info());
1305 xbt_assert(region1->object_info());
1307 /* Compare global variables */
1308 if (global_variables_differ(state_comparator, region1->object_info(), region1, region2, *s1, *s2)) {
1309 std::string const& name = region1->object_info()->file_name;
1310 XBT_VERB("(%d - %d) Different global variables in %s", s1->num_state_, s2->num_state_, name.c_str());
1316 if (mmalloc_heap_differ(state_comparator, *s1, *s2)) {
1317 XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", s1->num_state_, s2->num_state_);
1321 XBT_VERB("(%d - %d) No difference found", s1->num_state_, s2->num_state_);