1 /* Copyright (c) 2008-2020. 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 explicit 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<IgnoredHeapRegion>* to_ignore = nullptr;
59 std::vector<HeapArea> equals_to;
60 std::vector<Type*> types;
61 std::size_t heapsize = 0;
63 void initHeapInformation(const s_xbt_mheap_t* heap, const std::vector<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(const s_xbt_mheap_t* heap1, const s_xbt_mheap_t* heap2,
81 const std::vector<IgnoredHeapRegion>& i1, const std::vector<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(const HeapLocationPairs* list);
130 } // namespace simgrid
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(const 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_) = HeapArea(pair[1].block_, pair[1].fragment_);
179 this->equals_to_<2>(pair[1].block_, pair[1].fragment_) = HeapArea(pair[0].block_, pair[0].fragment_);
181 this->equals_to_<1>(pair[0].block_, 0) = HeapArea(pair[1].block_, pair[1].fragment_);
182 this->equals_to_<2>(pair[1].block_, 0) = HeapArea(pair[0].block_, pair[0].fragment_);
187 void ProcessComparisonState::initHeapInformation(const s_xbt_mheap_t* heap, const std::vector<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(const s_xbt_mheap_t* heap1, const s_xbt_mheap_t* heap2,
197 const std::vector<IgnoredHeapRegion>& i1,
198 const std::vector<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() == 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(StateComparator& state, const Snapshot& snapshot1, const Snapshot& snapshot2)
223 const RemoteClient& process = mc_model_checker->process();
225 /* Check busy blocks */
228 malloc_info heapinfo_temp1;
229 malloc_info heapinfo_temp2;
230 malloc_info heapinfo_temp2b;
232 const Region* heap_region1 = MC_get_heap_region(snapshot1);
233 const Region* heap_region2 = MC_get_heap_region(snapshot2);
235 // This is the address of std_heap->heapinfo in the application process:
236 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
238 // This is in snapshot do not use them directly:
239 const malloc_info* heapinfos1 =
240 snapshot1.read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
241 const malloc_info* heapinfos2 =
242 snapshot2.read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
244 while (i1 < state.heaplimit) {
245 const malloc_info* heapinfo1 =
246 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[i1], sizeof(malloc_info));
247 const malloc_info* heapinfo2 =
248 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[i1], sizeof(malloc_info));
250 if (heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type == MMALLOC_TYPE_HEAPINFO) { /* Free block */
255 xbt_assert(heapinfo1->type >= 0, "Unkown mmalloc block type: %d", heapinfo1->type);
257 void* addr_block1 = ((void*)(((ADDR2UINT(i1)) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase));
259 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
260 if (is_stack(addr_block1)) {
261 for (size_t k = 0; k < heapinfo1->busy_block.size; k++)
262 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
263 for (size_t k = 0; k < heapinfo2->busy_block.size; k++)
264 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
265 i1 += heapinfo1->busy_block.size;
269 if (state.equals_to_<1>(i1, 0).valid_) {
277 /* Try first to associate to same block in the other heap */
278 if (heapinfo2->type == heapinfo1->type && state.equals_to_<2>(i1, 0).valid_ == 0) {
279 const void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
280 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
281 for (size_t k = 1; k < heapinfo2->busy_block.size; k++)
282 state.equals_to_<2>(i1 + k, 0) = HeapArea(i1, -1);
283 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
284 state.equals_to_<1>(i1 + k, 0) = HeapArea(i1, -1);
286 i1 += heapinfo1->busy_block.size;
290 while (i2 < state.heaplimit && not equal) {
291 const void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
298 const malloc_info* heapinfo2b =
299 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
301 if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
306 if (state.equals_to_<2>(i2, 0).valid_) {
311 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
312 for (size_t k = 1; k < heapinfo2b->busy_block.size; k++)
313 state.equals_to_<2>(i2 + k, 0) = HeapArea(i1, -1);
314 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
315 state.equals_to_<1>(i1 + k, 0) = HeapArea(i2, -1);
317 i1 += heapinfo1->busy_block.size;
323 XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
326 } else { /* Fragmented block */
327 for (size_t j1 = 0; j1 < (size_t)(BLOCKSIZE >> heapinfo1->type); j1++) {
328 if (heapinfo1->busy_frag.frag_size[j1] == -1) /* Free fragment_ */
331 if (state.equals_to_<1>(i1, j1).valid_)
334 void* addr_frag1 = (void*)((char*)addr_block1 + (j1 << heapinfo1->type));
339 /* Try first to associate to same fragment_ in the other heap */
340 if (heapinfo2->type == heapinfo1->type && not state.equals_to_<2>(i1, j1).valid_) {
341 const void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
342 const void* addr_frag2 = (const char*)addr_block2 + (j1 << heapinfo2->type);
343 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0))
347 while (i2 < state.heaplimit && not equal) {
348 const malloc_info* heapinfo2b =
349 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
351 if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
356 // We currently do not match fragments with unfragmented blocks (maybe we should).
357 if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
362 xbt_assert(heapinfo2b->type >= 0, "Unkown mmalloc block type: %d", heapinfo2b->type);
364 for (size_t j2 = 0; j2 < (size_t)(BLOCKSIZE >> heapinfo2b->type); j2++) {
365 if (i2 == i1 && j2 == j1)
368 if (state.equals_to_<2>(i2, j2).valid_)
371 const void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
372 const void* addr_frag2 = (const char*)addr_block2 + (j2 << heapinfo2b->type);
374 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
383 XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
384 heapinfo1->busy_frag.frag_size[j1], addr_frag1);
392 /* All blocks/fragments are equal to another block/fragment_ ? */
393 for (size_t i = 1; i < state.heaplimit; i++) {
394 const malloc_info* heapinfo1 =
395 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[i], sizeof(malloc_info));
397 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo1->busy_block.busy_size > 0 &&
398 not state.equals_to_<1>(i, 0).valid_) {
399 XBT_DEBUG("Block %zu not found (size used = %zu)", i, heapinfo1->busy_block.busy_size);
403 if (heapinfo1->type <= 0)
405 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo1->type); j++)
406 if (i1 == state.heaplimit && heapinfo1->busy_frag.frag_size[j] > 0 && not state.equals_to_<1>(i, j).valid_) {
407 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)", i, j, heapinfo1->busy_frag.frag_size[j]);
412 for (size_t i = 1; i < state.heaplimit; i++) {
413 const malloc_info* heapinfo2 =
414 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[i], sizeof(malloc_info));
415 if (heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo2->busy_block.busy_size > 0 &&
416 not state.equals_to_<2>(i, 0).valid_) {
417 XBT_DEBUG("Block %zu not found (size used = %zu)", i,
418 heapinfo2->busy_block.busy_size);
422 if (heapinfo2->type <= 0)
425 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo2->type); j++)
426 if (i1 == state.heaplimit && heapinfo2->busy_frag.frag_size[j] > 0 && not state.equals_to_<2>(i, j).valid_) {
427 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)",
428 i, j, heapinfo2->busy_frag.frag_size[j]);
438 * @param real_area1 Process address for state 1
439 * @param real_area2 Process address for state 2
440 * @param snapshot1 Snapshot of state 1
441 * @param snapshot2 Snapshot of state 2
444 * @param check_ignore
445 * @return true when different, false otherwise (same or unknown)
447 static bool heap_area_differ_without_type(StateComparator& state, const void* real_area1, const void* real_area2,
448 const Snapshot& snapshot1, const Snapshot& snapshot2,
449 HeapLocationPairs* previous, int size, int check_ignore)
451 const RemoteClient& process = mc_model_checker->process();
452 const Region* heap_region1 = MC_get_heap_region(snapshot1);
453 const Region* heap_region2 = MC_get_heap_region(snapshot2);
455 for (int i = 0; i < size; ) {
456 if (check_ignore > 0) {
457 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, (const char*)real_area1 + i);
459 ssize_t ignore2 = heap_comparison_ignore_size(state.processStates[1].to_ignore, (const char*)real_area2 + i);
460 if (ignore2 == ignore1) {
472 if (MC_snapshot_region_memcmp((const char*)real_area1 + i, heap_region1, (const char*)real_area2 + i, heap_region2,
474 int pointer_align = (i / sizeof(void *)) * sizeof(void *);
475 const void* addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + pointer_align)));
476 const void* addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + pointer_align)));
478 if (process.in_maestro_stack(remote(addr_pointed1)) && process.in_maestro_stack(remote(addr_pointed2))) {
479 i = pointer_align + sizeof(void *);
483 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)) {
484 // Both addresses are in the heap:
485 if (heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, nullptr, 0))
487 i = pointer_align + sizeof(void *);
500 * @param real_area1 Process address for state 1
501 * @param real_area2 Process address for state 2
502 * @param snapshot1 Snapshot of state 1
503 * @param snapshot2 Snapshot of state 2
506 * @param area_size either a byte_size or an elements_count (?)
507 * @param check_ignore
508 * @param pointer_level
509 * @return true when different, false otherwise (same or unknown)
511 static bool heap_area_differ_with_type(StateComparator& state, const void* real_area1, const void* real_area2,
512 const Snapshot& snapshot1, const Snapshot& snapshot2,
513 HeapLocationPairs* previous, const Type* type, int area_size, int check_ignore,
516 // HACK: This should not happen but in practice, there are some
517 // DW_TAG_typedef without an associated DW_AT_type:
518 //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
519 // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
520 // <538837> DW_AT_decl_file : 98
521 // <538838> DW_AT_decl_line : 37
525 if (is_stack(real_area1) && is_stack(real_area2))
528 if (check_ignore > 0) {
529 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
530 if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
535 const Type* subsubtype;
537 const void* addr_pointed1;
538 const void* addr_pointed2;
540 const Region* heap_region1 = MC_get_heap_region(snapshot1);
541 const Region* heap_region2 = MC_get_heap_region(snapshot2);
543 switch (type->type) {
544 case DW_TAG_unspecified_type:
547 case DW_TAG_base_type:
548 if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
549 if (real_area1 == real_area2)
552 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
554 if (area_size != -1 && type->byte_size != area_size)
557 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
560 case DW_TAG_enumeration_type:
561 if (area_size != -1 && type->byte_size != area_size)
563 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
566 case DW_TAG_const_type:
567 case DW_TAG_volatile_type:
568 return heap_area_differ_with_type(state, real_area1, real_area2, snapshot1, snapshot2, previous, type->subtype,
569 area_size, check_ignore, pointer_level);
571 case DW_TAG_array_type:
572 subtype = type->subtype;
573 switch (subtype->type) {
574 case DW_TAG_unspecified_type:
577 case DW_TAG_base_type:
578 case DW_TAG_enumeration_type:
579 case DW_TAG_pointer_type:
580 case DW_TAG_reference_type:
581 case DW_TAG_rvalue_reference_type:
582 case DW_TAG_structure_type:
583 case DW_TAG_class_type:
584 case DW_TAG_union_type:
585 if (subtype->full_type)
586 subtype = subtype->full_type;
587 elm_size = subtype->byte_size;
589 // TODO, just remove the type indirection?
590 case DW_TAG_const_type:
592 case DW_TAG_volatile_type:
593 subsubtype = subtype->subtype;
594 if (subsubtype->full_type)
595 subsubtype = subsubtype->full_type;
596 elm_size = subsubtype->byte_size;
601 for (int i = 0; i < type->element_count; i++) {
602 // TODO, add support for variable stride (DW_AT_byte_stride)
603 if (heap_area_differ_with_type(state, (const char*)real_area1 + (i * elm_size),
604 (const char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
605 type->subtype, subtype->byte_size, check_ignore, pointer_level))
610 case DW_TAG_reference_type:
611 case DW_TAG_rvalue_reference_type:
612 case DW_TAG_pointer_type:
613 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
614 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
615 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
616 return (addr_pointed1 != addr_pointed2);
619 if (pointer_level <= 1) {
620 addr_pointed1 = snapshot1.read(remote((void* const*)real_area1));
621 addr_pointed2 = snapshot2.read(remote((void* const*)real_area2));
622 if (snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2))
623 return heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, type->subtype,
626 return (addr_pointed1 != addr_pointed2);
628 for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
629 addr_pointed1 = snapshot1.read(remote((void* const*)((const char*)real_area1 + i * sizeof(void*))));
630 addr_pointed2 = snapshot2.read(remote((void* const*)((const char*)real_area2 + i * sizeof(void*))));
631 bool differ = snapshot1.on_heap(addr_pointed1) && snapshot2.on_heap(addr_pointed2)
632 ? heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
633 type->subtype, pointer_level)
634 : addr_pointed1 != addr_pointed2;
640 case DW_TAG_structure_type:
641 case DW_TAG_class_type:
643 type = type->full_type;
644 if (type->byte_size == 0)
646 if (area_size != -1 && type->byte_size != area_size) {
647 if (area_size <= type->byte_size || area_size % type->byte_size != 0)
649 for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
650 if (heap_area_differ_with_type(state, (const char*)real_area1 + i * type->byte_size,
651 (const char*)real_area2 + i * type->byte_size, snapshot1, snapshot2, previous,
652 type, -1, check_ignore, 0))
656 for (const simgrid::mc::Member& member : type->members) {
657 // TODO, optimize this? (for the offset case)
658 const void* real_member1 = dwarf::resolve_member(real_area1, type, &member, &snapshot1);
659 const void* real_member2 = dwarf::resolve_member(real_area2, type, &member, &snapshot2);
660 if (heap_area_differ_with_type(state, real_member1, real_member2, snapshot1, snapshot2, previous,
661 member.type, -1, check_ignore, 0))
667 case DW_TAG_union_type:
668 return heap_area_differ_without_type(state, real_area1, real_area2, snapshot1, snapshot2, previous,
669 type->byte_size, check_ignore);
676 /** Infer the type of a part of the block from the type of the block
678 * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
680 * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
682 * @param type DWARF type ID of the root address
684 * @return DWARF type ID for given offset
686 static Type* get_offset_type(void* real_base_address, Type* type, int offset, int area_size, const Snapshot& snapshot)
688 // Beginning of the block, the inferred variable type if the type of the block:
692 switch (type->type) {
693 case DW_TAG_structure_type:
694 case DW_TAG_class_type:
696 type = type->full_type;
697 if (area_size != -1 && type->byte_size != area_size) {
698 if (area_size > type->byte_size && area_size % type->byte_size == 0)
704 for (const simgrid::mc::Member& member : type->members) {
705 if (member.has_offset_location()) {
706 // We have the offset, use it directly (shortcut):
707 if (member.offset() == offset)
710 void* real_member = dwarf::resolve_member(real_base_address, type, &member, &snapshot);
711 if ((char*)real_member - (char*)real_base_address == offset)
718 /* FIXME: other cases ? */
725 * @param area1 Process address for state 1
726 * @param area2 Process address for state 2
727 * @param snapshot1 Snapshot of state 1
728 * @param snapshot2 Snapshot of state 2
729 * @param previous Pairs of blocks already compared on the current path (or nullptr)
730 * @param type_id Type of variable
731 * @param pointer_level
732 * @return true when different, false otherwise (same or unknown)
734 static bool heap_area_differ(StateComparator& state, const void* area1, const void* area2, const Snapshot& snapshot1,
735 const Snapshot& snapshot2, HeapLocationPairs* previous, Type* type, int pointer_level)
737 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
742 int check_ignore = 0;
750 Type* new_type1 = nullptr;
751 Type* new_type2 = nullptr;
753 bool match_pairs = false;
755 // This is the address of std_heap->heapinfo in the application process:
756 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
758 const malloc_info* heapinfos1 = snapshot1.read(remote((const malloc_info**)heapinfo_address));
759 const malloc_info* heapinfos2 = snapshot2.read(remote((const malloc_info**)heapinfo_address));
761 malloc_info heapinfo_temp1;
762 malloc_info heapinfo_temp2;
764 simgrid::mc::HeapLocationPairs current;
765 if (previous == nullptr) {
771 block1 = ((const char*)area1 - (const char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
772 block2 = ((const char*)area2 - (const char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
774 // If either block is a stack block:
775 if (is_block_stack((int) block1) && is_block_stack((int) block2)) {
776 previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}});
778 state.match_equals(previous);
782 // If either block is not in the expected area of memory:
783 if (((const char*)area1 < (const char*)state.std_heap_copy.heapbase) ||
784 (block1 > (ssize_t)state.processStates[0].heapsize) || (block1 < 1) ||
785 ((const char*)area2 < (const char*)state.std_heap_copy.heapbase) ||
786 (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
790 // Process address of the block:
791 void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
792 void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
796 type = type->full_type;
798 // This assume that for "boring" types (volatile ...) byte_size is absent:
799 while (type->byte_size == 0 && type->subtype != nullptr)
800 type = type->subtype;
803 if (type->type == DW_TAG_pointer_type ||
804 (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
807 type_size = type->byte_size;
810 const Region* heap_region1 = MC_get_heap_region(snapshot1);
811 const Region* heap_region2 = MC_get_heap_region(snapshot2);
813 const malloc_info* heapinfo1 =
814 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info));
815 const malloc_info* heapinfo2 =
816 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info));
818 if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
819 && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
822 state.match_equals(previous);
826 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
829 // TODO, lookup variable type from block type as done for fragmented blocks
831 if (state.equals_to_<1>(block1, 0).valid_ && state.equals_to_<2>(block2, 0).valid_ &&
832 state.blocksEqual(block1, block2)) {
834 state.match_equals(previous);
838 if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
839 type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
840 (type->name.empty() || type->name == "struct s_smx_context")) {
842 state.match_equals(previous);
846 if (heapinfo1->busy_block.size != heapinfo2->busy_block.size ||
847 heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
850 if (not previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}}).second) {
852 state.match_equals(previous);
856 size = heapinfo1->busy_block.busy_size;
858 // Remember (basic) type inference.
859 // The current data structure only allows us to do this for the whole block.
860 if (type != nullptr && area1 == real_addr_block1)
861 state.types_<1>(block1, 0) = type;
862 if (type != nullptr && area2 == real_addr_block2)
863 state.types_<2>(block2, 0) = type;
867 state.match_equals(previous);
871 if (heapinfo1->busy_block.ignore > 0 && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
872 check_ignore = heapinfo1->busy_block.ignore;
874 } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
876 ssize_t frag1 = ((uintptr_t)(ADDR2UINT(area1) % (BLOCKSIZE))) >> heapinfo1->type;
877 ssize_t frag2 = ((uintptr_t)(ADDR2UINT(area2) % (BLOCKSIZE))) >> heapinfo2->type;
879 // Process address of the fragment_:
880 void* real_addr_frag1 = (void*)((char*)real_addr_block1 + (frag1 << heapinfo1->type));
881 void* real_addr_frag2 = (void*)((char*)real_addr_block2 + (frag2 << heapinfo2->type));
883 // Check the size of the fragments against the size of the type:
884 if (type_size != -1) {
885 if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
887 state.match_equals(previous);
891 if (type_size != heapinfo1->busy_frag.frag_size[frag1]
892 || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
894 state.match_equals(previous);
899 // Check if the blocks are already matched together:
900 if (state.equals_to_<1>(block1, frag1).valid_ && state.equals_to_<2>(block2, frag2).valid_ && offset1 == offset2 &&
901 state.fragmentsEqual(block1, frag1, block2, frag2)) {
903 state.match_equals(previous);
906 // Compare the size of both fragments:
907 if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
908 if (type_size == -1) {
910 state.match_equals(previous);
916 // Size of the fragment_:
917 size = heapinfo1->busy_frag.frag_size[frag1];
919 // Remember (basic) type inference.
920 // The current data structure only allows us to do this for the whole fragment_.
921 if (type != nullptr && area1 == real_addr_frag1)
922 state.types_<1>(block1, frag1) = type;
923 if (type != nullptr && area2 == real_addr_frag2)
924 state.types_<2>(block2, frag2) = type;
926 // The type of the variable is already known:
928 new_type1 = new_type2 = type;
930 // Type inference from the block type.
931 else if (state.types_<1>(block1, frag1) != nullptr || state.types_<2>(block2, frag2) != nullptr) {
932 offset1 = (const char*)area1 - (const char*)real_addr_frag1;
933 offset2 = (const char*)area2 - (const char*)real_addr_frag2;
935 if (state.types_<1>(block1, frag1) != nullptr && state.types_<2>(block2, frag2) != nullptr) {
936 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
937 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset1, size, snapshot2);
938 } else if (state.types_<1>(block1, frag1) != nullptr) {
939 new_type1 = get_offset_type(real_addr_frag1, state.types_<1>(block1, frag1), offset1, size, snapshot1);
940 new_type2 = get_offset_type(real_addr_frag2, state.types_<1>(block1, frag1), offset2, size, snapshot2);
941 } else if (state.types_<2>(block2, frag2) != nullptr) {
942 new_type1 = get_offset_type(real_addr_frag1, state.types_<2>(block2, frag2), offset1, size, snapshot1);
943 new_type2 = get_offset_type(real_addr_frag2, state.types_<2>(block2, frag2), offset2, size, snapshot2);
946 state.match_equals(previous);
950 if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
952 while (type->byte_size == 0 && type->subtype != nullptr)
953 type = type->subtype;
954 new_size1 = type->byte_size;
957 while (type->byte_size == 0 && type->subtype != nullptr)
958 type = type->subtype;
959 new_size2 = type->byte_size;
963 state.match_equals(previous);
968 if (new_size1 > 0 && new_size1 == new_size2) {
973 if (offset1 == 0 && offset2 == 0 &&
974 not previous->insert(HeapLocationPair{{HeapLocation(block1, frag1), HeapLocation(block2, frag2)}}).second) {
976 state.match_equals(previous);
982 state.match_equals(previous);
986 if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
987 (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
988 check_ignore = heapinfo1->busy_frag.ignore[frag1];
992 /* Start comparison */
994 type ? heap_area_differ_with_type(state, area1, area2, snapshot1, snapshot2, previous, type, size, check_ignore,
996 : heap_area_differ_without_type(state, area1, area2, snapshot1, snapshot2, previous, size, check_ignore);
1001 state.match_equals(previous);
1005 } // namespace simgrid
1007 /************************** Snapshot comparison *******************************/
1008 /******************************************************************************/
1010 static bool areas_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
1011 const simgrid::mc::Snapshot& snapshot1, simgrid::mc::Region* region1,
1012 const void* real_area2, const simgrid::mc::Snapshot& snapshot2,
1013 simgrid::mc::Region* region2, const simgrid::mc::Type* type, int pointer_level)
1015 const simgrid::mc::Type* subtype;
1016 const simgrid::mc::Type* subsubtype;
1020 xbt_assert(type != nullptr);
1021 switch (type->type) {
1022 case DW_TAG_unspecified_type:
1025 case DW_TAG_base_type:
1026 case DW_TAG_enumeration_type:
1027 case DW_TAG_union_type:
1028 return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
1029 case DW_TAG_typedef:
1030 case DW_TAG_volatile_type:
1031 case DW_TAG_const_type:
1032 return areas_differ_with_type(state, real_area1, snapshot1, region1, real_area2, snapshot2, region2,
1033 type->subtype, pointer_level);
1034 case DW_TAG_array_type:
1035 subtype = type->subtype;
1036 switch (subtype->type) {
1037 case DW_TAG_unspecified_type:
1040 case DW_TAG_base_type:
1041 case DW_TAG_enumeration_type:
1042 case DW_TAG_pointer_type:
1043 case DW_TAG_reference_type:
1044 case DW_TAG_rvalue_reference_type:
1045 case DW_TAG_structure_type:
1046 case DW_TAG_class_type:
1047 case DW_TAG_union_type:
1048 if (subtype->full_type)
1049 subtype = subtype->full_type;
1050 elm_size = subtype->byte_size;
1052 case DW_TAG_const_type:
1053 case DW_TAG_typedef:
1054 case DW_TAG_volatile_type:
1055 subsubtype = subtype->subtype;
1056 if (subsubtype->full_type)
1057 subsubtype = subsubtype->full_type;
1058 elm_size = subsubtype->byte_size;
1063 for (i = 0; i < type->element_count; i++) {
1064 size_t off = i * elm_size;
1065 if (areas_differ_with_type(state, (const char*)real_area1 + off, snapshot1, region1,
1066 (const char*)real_area2 + off, snapshot2, region2, type->subtype, pointer_level))
1070 case DW_TAG_pointer_type:
1071 case DW_TAG_reference_type:
1072 case DW_TAG_rvalue_reference_type: {
1073 const void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
1074 const void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
1076 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
1077 return (addr_pointed1 != addr_pointed2);
1078 if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
1080 if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
1082 if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
1087 // Some cases are not handled here:
1088 // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
1089 // * a pointer leads to the read-only segment of the current object
1090 // * a pointer lead to a different ELF object
1092 if (snapshot1.on_heap(addr_pointed1)) {
1093 if (not snapshot2.on_heap(addr_pointed2))
1095 // The pointers are both in the heap:
1096 return simgrid::mc::heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, nullptr,
1097 type->subtype, pointer_level);
1099 } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
1100 // The pointers are both in the current object R/W segment:
1101 if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
1103 if (not type->type_id)
1104 return (addr_pointed1 != addr_pointed2);
1106 return areas_differ_with_type(state, addr_pointed1, snapshot1, region1, addr_pointed2, snapshot2, region2,
1107 type->subtype, pointer_level);
1109 // TODO, We do not handle very well the case where
1110 // it belongs to a different (non-heap) region from the current one.
1112 return (addr_pointed1 != addr_pointed2);
1115 case DW_TAG_structure_type:
1116 case DW_TAG_class_type:
1117 for (const simgrid::mc::Member& member : type->members) {
1118 const void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, &snapshot1);
1119 const void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, &snapshot2);
1120 simgrid::mc::Region* subregion1 = snapshot1.get_region(member1, region1); // region1 is hinted
1121 simgrid::mc::Region* subregion2 = snapshot2.get_region(member2, region2); // region2 is hinted
1122 if (areas_differ_with_type(state, member1, snapshot1, subregion1, member2, snapshot2, subregion2, member.type,
1127 case DW_TAG_subroutine_type:
1130 XBT_VERB("Unknown case: %d", type->type);
1137 static bool global_variables_differ(simgrid::mc::StateComparator& state,
1138 const simgrid::mc::ObjectInformation* object_info, simgrid::mc::Region* r1,
1139 simgrid::mc::Region* r2, const simgrid::mc::Snapshot& snapshot1,
1140 const simgrid::mc::Snapshot& snapshot2)
1142 xbt_assert(r1 && r2, "Missing region.");
1144 const std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
1146 for (simgrid::mc::Variable const& current_var : variables) {
1147 // If the variable is not in this object, skip it:
1148 // We do not expect to find a pointer to something which is not reachable
1149 // by the global variables.
1150 if ((char *) current_var.address < (char *) object_info->start_rw
1151 || (char *) current_var.address > (char *) object_info->end_rw)
1154 const simgrid::mc::Type* bvariable_type = current_var.type;
1155 if (areas_differ_with_type(state, current_var.address, snapshot1, r1, current_var.address, snapshot2, r2,
1156 bvariable_type, 0)) {
1157 XBT_VERB("Global variable %s (%p) is different between snapshots", current_var.name.c_str(), current_var.address);
1165 static bool local_variables_differ(simgrid::mc::StateComparator& state, const simgrid::mc::Snapshot& snapshot1,
1166 const simgrid::mc::Snapshot& snapshot2, const_mc_snapshot_stack_t stack1,
1167 const_mc_snapshot_stack_t stack2)
1169 if (stack1->local_variables.size() != stack2->local_variables.size()) {
1170 XBT_VERB("Different number of local variables");
1174 for (unsigned int cursor = 0; cursor < stack1->local_variables.size(); cursor++) {
1175 const_local_variable_t current_var1 = &stack1->local_variables[cursor];
1176 const_local_variable_t current_var2 = &stack2->local_variables[cursor];
1177 if (current_var1->name != current_var2->name || current_var1->subprogram != current_var2->subprogram ||
1178 current_var1->ip != current_var2->ip) {
1179 // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
1180 XBT_VERB("Different name of variable (%s - %s) or frame (%s - %s) or ip (%lu - %lu)", current_var1->name.c_str(),
1181 current_var2->name.c_str(), current_var1->subprogram->name.c_str(),
1182 current_var2->subprogram->name.c_str(), current_var1->ip, current_var2->ip);
1186 if (areas_differ_with_type(state, current_var1->address, snapshot1, snapshot1.get_region(current_var1->address),
1187 current_var2->address, snapshot2, snapshot2.get_region(current_var2->address),
1188 current_var1->type, 0)) {
1189 XBT_VERB("Local variable %s (%p - %p) in frame %s is different between snapshots", current_var1->name.c_str(),
1190 current_var1->address, current_var2->address, current_var1->subprogram->name.c_str());
1200 bool snapshot_equal(const Snapshot* s1, const Snapshot* s2)
1202 // TODO, make this a field of ModelChecker or something similar
1203 static StateComparator state_comparator;
1205 const RemoteClient& process = mc_model_checker->process();
1207 if (s1->hash_ != s2->hash_) {
1208 XBT_VERB("(%d - %d) Different hash: 0x%" PRIx64 "--0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_,
1212 XBT_VERB("(%d - %d) Same hash: 0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_);
1214 /* Compare enabled processes */
1215 if (s1->enabled_processes_ != s2->enabled_processes_) {
1216 XBT_VERB("(%d - %d) Different amount of enabled processes", s1->num_state_, s2->num_state_);
1220 /* Compare size of stacks */
1221 for (unsigned long i = 0; i < s1->stacks_.size(); i++) {
1222 size_t size_used1 = s1->stack_sizes_[i];
1223 size_t size_used2 = s2->stack_sizes_[i];
1224 if (size_used1 != size_used2) {
1225 XBT_VERB("(%d - %d) Different size used in stacks: %zu - %zu", s1->num_state_, s2->num_state_, size_used1,
1231 /* Init heap information used in heap comparison algorithm */
1232 const s_xbt_mheap_t* heap1 = static_cast<xbt_mheap_t>(s1->read_bytes(
1233 alloca(sizeof(s_xbt_mheap_t)), sizeof(s_xbt_mheap_t), remote(process.heap_address), ReadOptions::lazy()));
1234 const s_xbt_mheap_t* heap2 = static_cast<xbt_mheap_t>(s2->read_bytes(
1235 alloca(sizeof(s_xbt_mheap_t)), sizeof(s_xbt_mheap_t), remote(process.heap_address), ReadOptions::lazy()));
1236 if (state_comparator.initHeapInformation(heap1, heap2, s1->to_ignore_, s2->to_ignore_) == -1) {
1237 XBT_VERB("(%d - %d) Different heap information", s1->num_state_, s2->num_state_);
1241 /* Stacks comparison */
1242 for (unsigned int cursor = 0; cursor < s1->stacks_.size(); cursor++) {
1243 const_mc_snapshot_stack_t stack1 = &s1->stacks_[cursor];
1244 const_mc_snapshot_stack_t stack2 = &s2->stacks_[cursor];
1246 if (local_variables_differ(state_comparator, *s1, *s2, stack1, stack2)) {
1247 XBT_VERB("(%d - %d) Different local variables between stacks %u", s1->num_state_, s2->num_state_, cursor + 1);
1252 size_t regions_count = s1->snapshot_regions_.size();
1253 if (regions_count != s2->snapshot_regions_.size())
1256 for (size_t k = 0; k != regions_count; ++k) {
1257 Region* region1 = s1->snapshot_regions_[k].get();
1258 Region* region2 = s2->snapshot_regions_[k].get();
1261 if (region1->region_type() != RegionType::Data)
1264 xbt_assert(region1->region_type() == region2->region_type());
1265 xbt_assert(region1->object_info() == region2->object_info());
1266 xbt_assert(region1->object_info());
1268 /* Compare global variables */
1269 if (global_variables_differ(state_comparator, region1->object_info(), region1, region2, *s1, *s2)) {
1270 std::string const& name = region1->object_info()->file_name;
1271 XBT_VERB("(%d - %d) Different global variables in %s", s1->num_state_, s2->num_state_, name.c_str());
1277 if (mmalloc_heap_differ(state_comparator, *s1, *s2)) {
1278 XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", s1->num_state_, s2->num_state_);
1282 XBT_VERB("(%d - %d) No difference found", s1->num_state_, s2->num_state_);
1287 } // namespace simgrid