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 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, 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(
81 xbt_mheap_t heap1, xbt_mheap_t heap2,
82 std::vector<simgrid::mc::IgnoredHeapRegion>* i1,
83 std::vector<simgrid::mc::IgnoredHeapRegion>* i2);
85 HeapArea& equals_to1_(std::size_t i, std::size_t j)
87 return processStates[0].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
89 HeapArea& equals_to2_(std::size_t i, std::size_t j)
91 return processStates[1].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
93 Type*& types1_(std::size_t i, std::size_t j)
95 return processStates[0].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
97 Type*& types2_(std::size_t i, std::size_t j)
99 return processStates[1].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
102 HeapArea const& equals_to1_(std::size_t i, std::size_t j) const
104 return processStates[0].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
106 HeapArea const& equals_to2_(std::size_t i, std::size_t j) const
108 return processStates[1].equals_to[ MAX_FRAGMENT_PER_BLOCK * i + j];
110 Type* const& types1_(std::size_t i, std::size_t j) const
112 return processStates[0].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
114 Type* const& types2_(std::size_t i, std::size_t j) const
116 return processStates[1].types[ MAX_FRAGMENT_PER_BLOCK * i + j];
119 /** Check whether two blocks are known to be matching
121 * @param b1 Block of state 1
122 * @param b2 Block of state 2
123 * @return if the blocks are known to be matching
125 bool blocksEqual(int b1, int b2) const
127 return this->equals_to1_(b1, 0).block_ == b2 && this->equals_to2_(b2, 0).block_ == b1;
130 /** Check whether two fragments are known to be matching
132 * @param b1 Block of state 1
133 * @param f1 Fragment of state 1
134 * @param b2 Block of state 2
135 * @param f2 Fragment of state 2
136 * @return if the fragments are known to be matching
138 int fragmentsEqual(int b1, int f1, int b2, int f2) const
140 return this->equals_to1_(b1, f1).block_ == b2 && this->equals_to1_(b1, f1).fragment_ == f2 &&
141 this->equals_to2_(b2, f2).block_ == b1 && this->equals_to2_(b2, f2).fragment_ == f1;
144 void match_equals(HeapLocationPairs* list);
150 /************************************************************************************/
152 static ssize_t heap_comparison_ignore_size(
153 std::vector<simgrid::mc::IgnoredHeapRegion>* ignore_list,
157 int end = ignore_list->size() - 1;
159 while (start <= end) {
160 unsigned int cursor = (start + end) / 2;
161 simgrid::mc::IgnoredHeapRegion const& region = (*ignore_list)[cursor];
162 if (region.address == address)
164 if (region.address < address)
166 if (region.address > address)
173 static bool is_on_heap(const void* address)
175 const xbt_mheap_t heap = mc_model_checker->process().get_heap();
176 return address >= heap->heapbase && address < heap->breakval;
179 static bool is_stack(const void *address)
181 for (auto const& stack : mc_model_checker->process().stack_areas())
182 if (address == stack.address)
187 // TODO, this should depend on the snapshot?
188 static bool is_block_stack(int block)
190 for (auto const& stack : mc_model_checker->process().stack_areas())
191 if (block == stack.block)
199 void StateComparator::match_equals(HeapLocationPairs* list)
201 for (auto const& pair : *list) {
202 if (pair[0].fragment_ != -1) {
203 this->equals_to1_(pair[0].block_, pair[0].fragment_) = simgrid::mc::HeapArea(pair[1].block_, pair[1].fragment_);
204 this->equals_to2_(pair[1].block_, pair[1].fragment_) = simgrid::mc::HeapArea(pair[0].block_, pair[0].fragment_);
206 this->equals_to1_(pair[0].block_, 0) = simgrid::mc::HeapArea(pair[1].block_, pair[1].fragment_);
207 this->equals_to2_(pair[1].block_, 0) = simgrid::mc::HeapArea(pair[0].block_, pair[0].fragment_);
212 void ProcessComparisonState::initHeapInformation(xbt_mheap_t heap,
213 std::vector<simgrid::mc::IgnoredHeapRegion>* i)
215 auto heaplimit = heap->heaplimit;
216 this->heapsize = heap->heapsize;
218 this->equals_to.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, HeapArea());
219 this->types.assign(heaplimit * MAX_FRAGMENT_PER_BLOCK, nullptr);
222 int StateComparator::initHeapInformation(xbt_mheap_t heap1, xbt_mheap_t heap2,
223 std::vector<simgrid::mc::IgnoredHeapRegion>* i1,
224 std::vector<simgrid::mc::IgnoredHeapRegion>* i2)
226 if ((heap1->heaplimit != heap2->heaplimit) || (heap1->heapsize != heap2->heapsize))
228 this->heaplimit = heap1->heaplimit;
229 this->std_heap_copy = *mc_model_checker->process().get_heap();
230 this->processStates[0].initHeapInformation(heap1, i1);
231 this->processStates[1].initHeapInformation(heap2, i2);
235 // TODO, have a robust way to find it in O(1)
236 static inline Region* MC_get_heap_region(Snapshot* snapshot)
238 for (auto const& region : snapshot->snapshot_regions_)
239 if (region->region_type() == simgrid::mc::RegionType::Heap)
241 xbt_die("No heap region");
244 static bool heap_area_differ(StateComparator& state, const void* area1, const void* area2, Snapshot* snapshot1,
245 Snapshot* snapshot2, HeapLocationPairs* previous, Type* type, int pointer_level);
247 static bool mmalloc_heap_differ(simgrid::mc::StateComparator& state, simgrid::mc::Snapshot* snapshot1,
248 simgrid::mc::Snapshot* snapshot2)
250 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
252 /* Check busy blocks */
255 malloc_info heapinfo_temp1;
256 malloc_info heapinfo_temp2;
257 malloc_info heapinfo_temp2b;
259 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
260 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
262 // This is the address of std_heap->heapinfo in the application process:
263 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
265 // This is in snapshot do not use them directly:
266 const malloc_info* heapinfos1 =
267 snapshot1->read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
268 const malloc_info* heapinfos2 =
269 snapshot2->read<malloc_info*>(RemotePtr<malloc_info*>((std::uint64_t)heapinfo_address));
271 while (i1 < state.heaplimit) {
273 const malloc_info* heapinfo1 =
274 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[i1], sizeof(malloc_info));
275 const malloc_info* heapinfo2 =
276 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[i1], sizeof(malloc_info));
278 if (heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type == MMALLOC_TYPE_HEAPINFO) { /* Free block */
283 if (heapinfo1->type < 0) {
284 fprintf(stderr, "Unkown mmalloc block type.\n");
288 void* addr_block1 = ((void*)(((ADDR2UINT(i1)) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase));
290 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED) { /* Large block */
292 if (is_stack(addr_block1)) {
293 for (size_t k = 0; k < heapinfo1->busy_block.size; k++)
294 state.equals_to1_(i1 + k, 0) = HeapArea(i1, -1);
295 for (size_t k = 0; k < heapinfo2->busy_block.size; k++)
296 state.equals_to2_(i1 + k, 0) = HeapArea(i1, -1);
297 i1 += heapinfo1->busy_block.size;
301 if (state.equals_to1_(i1, 0).valid_) {
309 /* Try first to associate to same block in the other heap */
310 if (heapinfo2->type == heapinfo1->type && state.equals_to2_(i1, 0).valid_ == 0) {
311 void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
312 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
313 for (size_t k = 1; k < heapinfo2->busy_block.size; k++)
314 state.equals_to2_(i1 + k, 0) = HeapArea(i1, -1);
315 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
316 state.equals_to1_(i1 + k, 0) = HeapArea(i1, -1);
318 i1 += heapinfo1->busy_block.size;
322 while (i2 < state.heaplimit && not equal) {
324 void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
331 const malloc_info* heapinfo2b =
332 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
334 if (heapinfo2b->type != MMALLOC_TYPE_UNFRAGMENTED) {
339 if (state.equals_to2_(i2, 0).valid_) {
344 if (not heap_area_differ(state, addr_block1, addr_block2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
345 for (size_t k = 1; k < heapinfo2b->busy_block.size; k++)
346 state.equals_to2_(i2 + k, 0) = HeapArea(i1, -1);
347 for (size_t k = 1; k < heapinfo1->busy_block.size; k++)
348 state.equals_to1_(i1 + k, 0) = HeapArea(i2, -1);
350 i1 += heapinfo1->busy_block.size;
357 XBT_DEBUG("Block %zu not found (size_used = %zu, addr = %p)", i1, heapinfo1->busy_block.busy_size, addr_block1);
361 } else { /* Fragmented block */
363 for (size_t j1 = 0; j1 < (size_t)(BLOCKSIZE >> heapinfo1->type); j1++) {
365 if (heapinfo1->busy_frag.frag_size[j1] == -1) /* Free fragment_ */
368 if (state.equals_to1_(i1, j1).valid_)
371 void* addr_frag1 = (void*)((char*)addr_block1 + (j1 << heapinfo1->type));
376 /* Try first to associate to same fragment_ in the other heap */
377 if (heapinfo2->type == heapinfo1->type && not state.equals_to2_(i1, j1).valid_) {
378 void* addr_block2 = (ADDR2UINT(i1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
379 void* addr_frag2 = (void*)((char*)addr_block2 + (j1 << heapinfo2->type));
380 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0))
384 while (i2 < state.heaplimit && not equal) {
386 const malloc_info* heapinfo2b =
387 (const malloc_info*)heap_region2->read(&heapinfo_temp2b, &heapinfos2[i2], sizeof(malloc_info));
389 if (heapinfo2b->type == MMALLOC_TYPE_FREE || heapinfo2b->type == MMALLOC_TYPE_HEAPINFO) {
394 // We currently do not match fragments with unfragmented blocks (maybe we should).
395 if (heapinfo2b->type == MMALLOC_TYPE_UNFRAGMENTED) {
400 if (heapinfo2b->type < 0) {
401 fprintf(stderr, "Unknown mmalloc block type.\n");
405 for (size_t j2 = 0; j2 < (size_t)(BLOCKSIZE >> heapinfo2b->type); j2++) {
407 if (i2 == i1 && j2 == j1)
410 if (state.equals_to2_(i2, j2).valid_)
413 void* addr_block2 = (ADDR2UINT(i2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
414 void* addr_frag2 = (void*)((char*)addr_block2 + (j2 << heapinfo2b->type));
416 if (not heap_area_differ(state, addr_frag1, addr_frag2, snapshot1, snapshot2, nullptr, nullptr, 0)) {
426 XBT_DEBUG("Block %zu, fragment_ %zu not found (size_used = %zd, address = %p)\n", i1, j1,
427 heapinfo1->busy_frag.frag_size[j1], addr_frag1);
436 /* All blocks/fragments are equal to another block/fragment_ ? */
437 for (size_t i = 1; i < state.heaplimit; i++) {
438 const malloc_info* heapinfo1 =
439 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[i], sizeof(malloc_info));
441 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo1->busy_block.busy_size > 0 &&
442 not state.equals_to1_(i, 0).valid_) {
443 XBT_DEBUG("Block %zu not found (size used = %zu)", i, heapinfo1->busy_block.busy_size);
447 if (heapinfo1->type <= 0)
449 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo1->type); j++)
450 if (i1 == state.heaplimit && heapinfo1->busy_frag.frag_size[j] > 0 && not state.equals_to1_(i, j).valid_) {
451 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)", i, j, heapinfo1->busy_frag.frag_size[j]);
456 for (size_t i = 1; i < state.heaplimit; i++) {
457 const malloc_info* heapinfo2 =
458 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[i], sizeof(malloc_info));
459 if (heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED && i1 == state.heaplimit && heapinfo2->busy_block.busy_size > 0 &&
460 not state.equals_to2_(i, 0).valid_) {
461 XBT_DEBUG("Block %zu not found (size used = %zu)", i,
462 heapinfo2->busy_block.busy_size);
466 if (heapinfo2->type <= 0)
469 for (size_t j = 0; j < (size_t)(BLOCKSIZE >> heapinfo2->type); j++)
470 if (i1 == state.heaplimit && heapinfo2->busy_frag.frag_size[j] > 0 && not state.equals_to2_(i, j).valid_) {
471 XBT_DEBUG("Block %zu, Fragment %zu not found (size used = %zd)",
472 i, j, heapinfo2->busy_frag.frag_size[j]);
483 * @param real_area1 Process address for state 1
484 * @param real_area2 Process address for state 2
485 * @param snapshot1 Snapshot of state 1
486 * @param snapshot2 Snapshot of state 2
489 * @param check_ignore
490 * @return true when different, false otherwise (same or unknown)
492 static bool heap_area_differ_without_type(simgrid::mc::StateComparator& state, const void* real_area1,
493 const void* real_area2, simgrid::mc::Snapshot* snapshot1,
494 simgrid::mc::Snapshot* snapshot2, HeapLocationPairs* previous, int size,
497 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
498 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
499 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
501 for (int i = 0; i < size; ) {
503 if (check_ignore > 0) {
504 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, (const char*)real_area1 + i);
506 ssize_t ignore2 = heap_comparison_ignore_size(state.processStates[1].to_ignore, (const char*)real_area2 + i);
507 if (ignore2 == ignore1) {
520 if (MC_snapshot_region_memcmp((const char*)real_area1 + i, heap_region1, (const char*)real_area2 + i, heap_region2,
523 int pointer_align = (i / sizeof(void *)) * sizeof(void *);
524 const void* addr_pointed1 = snapshot1->read(remote((void**)((const char*)real_area1 + pointer_align)));
525 const void* addr_pointed2 = snapshot2->read(remote((void**)((const char*)real_area2 + pointer_align)));
527 if (process.in_maestro_stack(remote(addr_pointed1)) && process.in_maestro_stack(remote(addr_pointed2))) {
528 i = pointer_align + sizeof(void *);
532 if (is_on_heap(addr_pointed1) && is_on_heap(addr_pointed2)) {
533 // Both addresses are in the heap:
534 if (heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, nullptr, 0))
536 i = pointer_align + sizeof(void *);
552 * @param real_area1 Process address for state 1
553 * @param real_area2 Process address for state 2
554 * @param snapshot1 Snapshot of state 1
555 * @param snapshot2 Snapshot of state 2
558 * @param area_size either a byte_size or an elements_count (?)
559 * @param check_ignore
560 * @param pointer_level
561 * @return true when different, false otherwise (same or unknown)
563 static bool heap_area_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
564 const void* real_area2, simgrid::mc::Snapshot* snapshot1,
565 simgrid::mc::Snapshot* snapshot2, HeapLocationPairs* previous,
566 simgrid::mc::Type* type, int area_size, int check_ignore, int pointer_level)
568 // HACK: This should not happen but in pratice, there are some
569 // DW_TAG_typedef without an associated DW_AT_type:
570 //<1><538832>: Abbrev Number: 111 (DW_TAG_typedef)
571 // <538833> DW_AT_name : (indirect string, offset: 0x2292f3): gregset_t
572 // <538837> DW_AT_decl_file : 98
573 // <538838> DW_AT_decl_line : 37
577 if (is_stack(real_area1) && is_stack(real_area2))
580 if (check_ignore > 0) {
581 ssize_t ignore1 = heap_comparison_ignore_size(state.processStates[0].to_ignore, real_area1);
582 if (ignore1 > 0 && heap_comparison_ignore_size(state.processStates[1].to_ignore, real_area2) == ignore1)
586 simgrid::mc::Type* subtype;
587 simgrid::mc::Type* subsubtype;
589 const void* addr_pointed1;
590 const void* addr_pointed2;
592 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
593 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
595 switch (type->type) {
596 case DW_TAG_unspecified_type:
599 case DW_TAG_base_type:
600 if (not type->name.empty() && type->name == "char") { /* String, hence random (arbitrary ?) size */
601 if (real_area1 == real_area2)
604 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, area_size) != 0;
606 if (area_size != -1 && type->byte_size != area_size)
609 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
612 case DW_TAG_enumeration_type:
613 if (area_size != -1 && type->byte_size != area_size)
615 return MC_snapshot_region_memcmp(real_area1, heap_region1, real_area2, heap_region2, type->byte_size) != 0;
618 case DW_TAG_const_type:
619 case DW_TAG_volatile_type:
620 return heap_area_differ_with_type(state, real_area1, real_area2, snapshot1, snapshot2, previous, type->subtype,
621 area_size, check_ignore, pointer_level);
623 case DW_TAG_array_type:
624 subtype = type->subtype;
625 switch (subtype->type) {
626 case DW_TAG_unspecified_type:
629 case DW_TAG_base_type:
630 case DW_TAG_enumeration_type:
631 case DW_TAG_pointer_type:
632 case DW_TAG_reference_type:
633 case DW_TAG_rvalue_reference_type:
634 case DW_TAG_structure_type:
635 case DW_TAG_class_type:
636 case DW_TAG_union_type:
637 if (subtype->full_type)
638 subtype = subtype->full_type;
639 elm_size = subtype->byte_size;
641 // TODO, just remove the type indirection?
642 case DW_TAG_const_type:
644 case DW_TAG_volatile_type:
645 subsubtype = subtype->subtype;
646 if (subsubtype->full_type)
647 subsubtype = subsubtype->full_type;
648 elm_size = subsubtype->byte_size;
653 for (int i = 0; i < type->element_count; i++) {
654 // TODO, add support for variable stride (DW_AT_byte_stride)
655 if (heap_area_differ_with_type(state, (const char*)real_area1 + (i * elm_size),
656 (const char*)real_area2 + (i * elm_size), snapshot1, snapshot2, previous,
657 type->subtype, subtype->byte_size, check_ignore, pointer_level))
662 case DW_TAG_reference_type:
663 case DW_TAG_rvalue_reference_type:
664 case DW_TAG_pointer_type:
665 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type) {
666 addr_pointed1 = snapshot1->read(remote((void* const*)real_area1));
667 addr_pointed2 = snapshot2->read(remote((void* const*)real_area2));
668 return (addr_pointed1 != addr_pointed2);
671 if (pointer_level <= 1) {
672 addr_pointed1 = snapshot1->read(remote((void* const*)real_area1));
673 addr_pointed2 = snapshot2->read(remote((void* const*)real_area2));
674 if (is_on_heap(addr_pointed1) && is_on_heap(addr_pointed2))
675 return heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous, type->subtype,
678 return (addr_pointed1 != addr_pointed2);
680 for (size_t i = 0; i < (area_size / sizeof(void*)); i++) {
681 addr_pointed1 = snapshot1->read(remote((void* const*)((const char*)real_area1 + i * sizeof(void*))));
682 addr_pointed2 = snapshot2->read(remote((void* const*)((const char*)real_area2 + i * sizeof(void*))));
683 bool differ = is_on_heap(addr_pointed1) && is_on_heap(addr_pointed2)
684 ? heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, previous,
685 type->subtype, pointer_level)
686 : addr_pointed1 != addr_pointed2;
692 case DW_TAG_structure_type:
693 case DW_TAG_class_type:
695 type = type->full_type;
696 if (area_size != -1 && type->byte_size != area_size) {
697 if (area_size <= type->byte_size || area_size % type->byte_size != 0)
699 for (size_t i = 0; i < (size_t)(area_size / type->byte_size); i++) {
700 if (heap_area_differ_with_type(state, (const char*)real_area1 + i * type->byte_size,
701 (const char*)real_area2 + i * type->byte_size, snapshot1, snapshot2, previous,
702 type, -1, check_ignore, 0))
706 for (simgrid::mc::Member& member : type->members) {
707 // TODO, optimize this? (for the offset case)
709 simgrid::dwarf::resolve_member(real_area1, type, &member, (simgrid::mc::AddressSpace*)snapshot1);
711 simgrid::dwarf::resolve_member(real_area2, type, &member, (simgrid::mc::AddressSpace*)snapshot2);
712 if (heap_area_differ_with_type(state, real_member1, real_member2, snapshot1, snapshot2, previous,
713 member.type, -1, check_ignore, 0))
719 case DW_TAG_union_type:
720 return heap_area_differ_without_type(state, real_area1, real_area2, snapshot1, snapshot2, previous,
721 type->byte_size, check_ignore);
724 XBT_VERB("Unknown case: %d", type->type);
730 /** Infer the type of a part of the block from the type of the block
732 * TODO, handle DW_TAG_array_type as well as arrays of the object ((*p)[5], p[5])
734 * TODO, handle subfields ((*p).bar.foo, (*p)[5].bar…)
736 * @param type DWARF type ID of the root address
738 * @return DWARF type ID for given offset
740 static simgrid::mc::Type* get_offset_type(void* real_base_address, simgrid::mc::Type* type, int offset, int area_size,
741 simgrid::mc::Snapshot* snapshot)
744 // Beginning of the block, the infered variable type if the type of the block:
748 switch (type->type) {
750 case DW_TAG_structure_type:
751 case DW_TAG_class_type:
753 type = type->full_type;
754 if (area_size != -1 && type->byte_size != area_size) {
755 if (area_size > type->byte_size && area_size % type->byte_size == 0)
761 for (simgrid::mc::Member& member : type->members) {
762 if (member.has_offset_location()) {
763 // We have the offset, use it directly (shortcut):
764 if (member.offset() == offset)
767 void* real_member = simgrid::dwarf::resolve_member(real_base_address, type, &member, snapshot);
768 if ((char*)real_member - (char*)real_base_address == offset)
775 /* FIXME: other cases ? */
783 * @param area1 Process address for state 1
784 * @param area2 Process address for state 2
785 * @param snapshot1 Snapshot of state 1
786 * @param snapshot2 Snapshot of state 2
787 * @param previous Pairs of blocks already compared on the current path (or nullptr)
788 * @param type_id Type of variable
789 * @param pointer_level
790 * @return true when different, false otherwise (same or unknown)
792 static bool heap_area_differ(simgrid::mc::StateComparator& state, const void* area1, const void* area2,
793 simgrid::mc::Snapshot* snapshot1, simgrid::mc::Snapshot* snapshot2,
794 HeapLocationPairs* previous, simgrid::mc::Type* type, int pointer_level)
796 const simgrid::mc::RemoteClient& process = mc_model_checker->process();
801 int check_ignore = 0;
809 simgrid::mc::Type* new_type1 = nullptr;
810 simgrid::mc::Type* new_type2 = nullptr;
812 bool match_pairs = false;
814 // This is the address of std_heap->heapinfo in the application process:
815 void* heapinfo_address = &((xbt_mheap_t)process.heap_address)->heapinfo;
817 const malloc_info* heapinfos1 = snapshot1->read(remote((const malloc_info**)heapinfo_address));
818 const malloc_info* heapinfos2 = snapshot2->read(remote((const malloc_info**)heapinfo_address));
820 malloc_info heapinfo_temp1;
821 malloc_info heapinfo_temp2;
823 simgrid::mc::HeapLocationPairs current;
824 if (previous == nullptr) {
830 block1 = ((char*)area1 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
831 block2 = ((char*)area2 - (char*)state.std_heap_copy.heapbase) / BLOCKSIZE + 1;
833 // If either block is a stack block:
834 if (is_block_stack((int) block1) && is_block_stack((int) block2)) {
835 previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}});
837 state.match_equals(previous);
841 // If either block is not in the expected area of memory:
842 if (((char*)area1 < (char*)state.std_heap_copy.heapbase) || (block1 > (ssize_t)state.processStates[0].heapsize) ||
843 (block1 < 1) || ((char*)area2 < (char*)state.std_heap_copy.heapbase) ||
844 (block2 > (ssize_t)state.processStates[1].heapsize) || (block2 < 1)) {
848 // Process address of the block:
849 void* real_addr_block1 = (ADDR2UINT(block1) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
850 void* real_addr_block2 = (ADDR2UINT(block2) - 1) * BLOCKSIZE + (char*)state.std_heap_copy.heapbase;
854 type = type->full_type;
856 // This assume that for "boring" types (volatile ...) byte_size is absent:
857 while (type->byte_size == 0 && type->subtype != nullptr)
858 type = type->subtype;
861 if (type->type == DW_TAG_pointer_type ||
862 (type->type == DW_TAG_base_type && not type->name.empty() && type->name == "char"))
865 type_size = type->byte_size;
869 simgrid::mc::Region* heap_region1 = MC_get_heap_region(snapshot1);
870 simgrid::mc::Region* heap_region2 = MC_get_heap_region(snapshot2);
872 const malloc_info* heapinfo1 =
873 (const malloc_info*)heap_region1->read(&heapinfo_temp1, &heapinfos1[block1], sizeof(malloc_info));
874 const malloc_info* heapinfo2 =
875 (const malloc_info*)heap_region2->read(&heapinfo_temp2, &heapinfos2[block2], sizeof(malloc_info));
877 if ((heapinfo1->type == MMALLOC_TYPE_FREE || heapinfo1->type==MMALLOC_TYPE_HEAPINFO)
878 && (heapinfo2->type == MMALLOC_TYPE_FREE || heapinfo2->type ==MMALLOC_TYPE_HEAPINFO)) {
881 state.match_equals(previous);
885 if (heapinfo1->type == MMALLOC_TYPE_UNFRAGMENTED && heapinfo2->type == MMALLOC_TYPE_UNFRAGMENTED) {
888 // TODO, lookup variable type from block type as done for fragmented blocks
890 if (state.equals_to1_(block1, 0).valid_ && state.equals_to2_(block2, 0).valid_ &&
891 state.blocksEqual(block1, block2)) {
893 state.match_equals(previous);
897 if (type_size != -1 && type_size != (ssize_t)heapinfo1->busy_block.busy_size &&
898 type_size != (ssize_t)heapinfo2->busy_block.busy_size &&
899 (type->name.empty() || type->name == "struct s_smx_context")) {
901 state.match_equals(previous);
905 if (heapinfo1->busy_block.size != heapinfo2->busy_block.size ||
906 heapinfo1->busy_block.busy_size != heapinfo2->busy_block.busy_size)
909 if (not previous->insert(HeapLocationPair{{HeapLocation(block1, -1), HeapLocation(block2, -1)}}).second) {
911 state.match_equals(previous);
915 size = heapinfo1->busy_block.busy_size;
917 // Remember (basic) type inference.
918 // The current data structure only allows us to do this for the whole block.
919 if (type != nullptr && area1 == real_addr_block1)
920 state.types1_(block1, 0) = type;
921 if (type != nullptr && area2 == real_addr_block2)
922 state.types2_(block2, 0) = type;
926 state.match_equals(previous);
930 if (heapinfo1->busy_block.ignore > 0
931 && heapinfo2->busy_block.ignore == heapinfo1->busy_block.ignore)
932 check_ignore = heapinfo1->busy_block.ignore;
934 } else if ((heapinfo1->type > 0) && (heapinfo2->type > 0)) { /* Fragmented block */
937 ssize_t frag1 = ((uintptr_t)(ADDR2UINT(area1) % (BLOCKSIZE))) >> heapinfo1->type;
938 ssize_t frag2 = ((uintptr_t)(ADDR2UINT(area2) % (BLOCKSIZE))) >> heapinfo2->type;
940 // Process address of the fragment_:
941 void* real_addr_frag1 = (void*)((char*)real_addr_block1 + (frag1 << heapinfo1->type));
942 void* real_addr_frag2 = (void*)((char*)real_addr_block2 + (frag2 << heapinfo2->type));
944 // Check the size of the fragments against the size of the type:
945 if (type_size != -1) {
946 if (heapinfo1->busy_frag.frag_size[frag1] == -1 || heapinfo2->busy_frag.frag_size[frag2] == -1) {
948 state.match_equals(previous);
952 if (type_size != heapinfo1->busy_frag.frag_size[frag1]
953 || type_size != heapinfo2->busy_frag.frag_size[frag2]) {
955 state.match_equals(previous);
960 // Check if the blocks are already matched together:
961 if (state.equals_to1_(block1, frag1).valid_ && state.equals_to2_(block2, frag2).valid_ && offset1 == offset2 &&
962 state.fragmentsEqual(block1, frag1, block2, frag2)) {
964 state.match_equals(previous);
967 // Compare the size of both fragments:
968 if (heapinfo1->busy_frag.frag_size[frag1] != heapinfo2->busy_frag.frag_size[frag2]) {
969 if (type_size == -1) {
971 state.match_equals(previous);
977 // Size of the fragment_:
978 size = heapinfo1->busy_frag.frag_size[frag1];
980 // Remember (basic) type inference.
981 // The current data structure only allows us to do this for the whole fragment_.
982 if (type != nullptr && area1 == real_addr_frag1)
983 state.types1_(block1, frag1) = type;
984 if (type != nullptr && area2 == real_addr_frag2)
985 state.types2_(block2, frag2) = type;
987 // The type of the variable is already known:
989 new_type1 = new_type2 = type;
991 // Type inference from the block type.
992 else if (state.types1_(block1, frag1) != nullptr || state.types2_(block2, frag2) != nullptr) {
994 offset1 = (char*)area1 - (char*)real_addr_frag1;
995 offset2 = (char*)area2 - (char*)real_addr_frag2;
997 if (state.types1_(block1, frag1) != nullptr && state.types2_(block2, frag2) != nullptr) {
998 new_type1 = get_offset_type(real_addr_frag1, state.types1_(block1, frag1), offset1, size, snapshot1);
999 new_type2 = get_offset_type(real_addr_frag2, state.types2_(block2, frag2), offset1, size, snapshot2);
1000 } else if (state.types1_(block1, frag1) != nullptr) {
1001 new_type1 = get_offset_type(real_addr_frag1, state.types1_(block1, frag1), offset1, size, snapshot1);
1002 new_type2 = get_offset_type(real_addr_frag2, state.types1_(block1, frag1), offset2, size, snapshot2);
1003 } else if (state.types2_(block2, frag2) != nullptr) {
1004 new_type1 = get_offset_type(real_addr_frag1, state.types2_(block2, frag2), offset1, size, snapshot1);
1005 new_type2 = get_offset_type(real_addr_frag2, state.types2_(block2, frag2), offset2, size, snapshot2);
1008 state.match_equals(previous);
1012 if (new_type1 != nullptr && new_type2 != nullptr && new_type1 != new_type2) {
1015 while (type->byte_size == 0 && type->subtype != nullptr)
1016 type = type->subtype;
1017 new_size1 = type->byte_size;
1020 while (type->byte_size == 0 && type->subtype != nullptr)
1021 type = type->subtype;
1022 new_size2 = type->byte_size;
1026 state.match_equals(previous);
1031 if (new_size1 > 0 && new_size1 == new_size2) {
1036 if (offset1 == 0 && offset2 == 0 &&
1037 not previous->insert(HeapLocationPair{{HeapLocation(block1, frag1), HeapLocation(block2, frag2)}}).second) {
1039 state.match_equals(previous);
1045 state.match_equals(previous);
1049 if ((heapinfo1->busy_frag.ignore[frag1] > 0) &&
1050 (heapinfo2->busy_frag.ignore[frag2] == heapinfo1->busy_frag.ignore[frag1]))
1051 check_ignore = heapinfo1->busy_frag.ignore[frag1];
1056 /* Start comparison */
1058 type ? heap_area_differ_with_type(state, area1, area2, snapshot1, snapshot2, previous, type, size, check_ignore,
1060 : heap_area_differ_without_type(state, area1, area2, snapshot1, snapshot2, previous, size, check_ignore);
1065 state.match_equals(previous);
1072 /************************** Snapshot comparison *******************************/
1073 /******************************************************************************/
1075 static bool areas_differ_with_type(simgrid::mc::StateComparator& state, const void* real_area1,
1076 simgrid::mc::Snapshot* snapshot1, simgrid::mc::Region* region1,
1077 const void* real_area2, simgrid::mc::Snapshot* snapshot2,
1078 simgrid::mc::Region* region2, simgrid::mc::Type* type, int pointer_level)
1080 simgrid::mc::Type* subtype;
1081 simgrid::mc::Type* subsubtype;
1085 xbt_assert(type != nullptr);
1086 switch (type->type) {
1087 case DW_TAG_unspecified_type:
1090 case DW_TAG_base_type:
1091 case DW_TAG_enumeration_type:
1092 case DW_TAG_union_type:
1093 return MC_snapshot_region_memcmp(real_area1, region1, real_area2, region2, type->byte_size) != 0;
1094 case DW_TAG_typedef:
1095 case DW_TAG_volatile_type:
1096 case DW_TAG_const_type:
1097 return areas_differ_with_type(state, real_area1, snapshot1, region1, real_area2, snapshot2, region2,
1098 type->subtype, pointer_level);
1099 case DW_TAG_array_type:
1100 subtype = type->subtype;
1101 switch (subtype->type) {
1102 case DW_TAG_unspecified_type:
1105 case DW_TAG_base_type:
1106 case DW_TAG_enumeration_type:
1107 case DW_TAG_pointer_type:
1108 case DW_TAG_reference_type:
1109 case DW_TAG_rvalue_reference_type:
1110 case DW_TAG_structure_type:
1111 case DW_TAG_class_type:
1112 case DW_TAG_union_type:
1113 if (subtype->full_type)
1114 subtype = subtype->full_type;
1115 elm_size = subtype->byte_size;
1117 case DW_TAG_const_type:
1118 case DW_TAG_typedef:
1119 case DW_TAG_volatile_type:
1120 subsubtype = subtype->subtype;
1121 if (subsubtype->full_type)
1122 subsubtype = subsubtype->full_type;
1123 elm_size = subsubtype->byte_size;
1128 for (i = 0; i < type->element_count; i++) {
1129 size_t off = i * elm_size;
1130 if (areas_differ_with_type(state, (char*)real_area1 + off, snapshot1, region1, (char*)real_area2 + off,
1131 snapshot2, region2, type->subtype, pointer_level))
1135 case DW_TAG_pointer_type:
1136 case DW_TAG_reference_type:
1137 case DW_TAG_rvalue_reference_type: {
1138 const void* addr_pointed1 = MC_region_read_pointer(region1, real_area1);
1139 const void* addr_pointed2 = MC_region_read_pointer(region2, real_area2);
1141 if (type->subtype && type->subtype->type == DW_TAG_subroutine_type)
1142 return (addr_pointed1 != addr_pointed2);
1143 if (addr_pointed1 == nullptr && addr_pointed2 == nullptr)
1145 if (addr_pointed1 == nullptr || addr_pointed2 == nullptr)
1147 if (not state.compared_pointers.insert(std::make_pair(addr_pointed1, addr_pointed2)).second)
1152 // Some cases are not handled here:
1153 // * the pointers lead to different areas (one to the heap, the other to the RW segment ...)
1154 // * a pointer leads to the read-only segment of the current object
1155 // * a pointer lead to a different ELF object
1157 if (is_on_heap(addr_pointed1)) {
1158 if (not is_on_heap(addr_pointed2))
1160 // The pointers are both in the heap:
1161 return simgrid::mc::heap_area_differ(state, addr_pointed1, addr_pointed2, snapshot1, snapshot2, nullptr,
1162 type->subtype, pointer_level);
1164 } else if (region1->contain(simgrid::mc::remote(addr_pointed1))) {
1165 // The pointers are both in the current object R/W segment:
1166 if (not region2->contain(simgrid::mc::remote(addr_pointed2)))
1168 if (not type->type_id)
1169 return (addr_pointed1 != addr_pointed2);
1171 return areas_differ_with_type(state, addr_pointed1, snapshot1, region1, addr_pointed2, snapshot2, region2,
1172 type->subtype, pointer_level);
1175 // TODO, We do not handle very well the case where
1176 // it belongs to a different (non-heap) region from the current one.
1178 return (addr_pointed1 != addr_pointed2);
1181 case DW_TAG_structure_type:
1182 case DW_TAG_class_type:
1183 for (simgrid::mc::Member& member : type->members) {
1184 void* member1 = simgrid::dwarf::resolve_member(real_area1, type, &member, snapshot1);
1185 void* member2 = simgrid::dwarf::resolve_member(real_area2, type, &member, snapshot2);
1186 simgrid::mc::Region* subregion1 = snapshot1->get_region(member1, region1); // region1 is hinted
1187 simgrid::mc::Region* subregion2 = snapshot2->get_region(member2, region2); // region2 is hinted
1188 if (areas_differ_with_type(state, member1, snapshot1, subregion1, member2, snapshot2, subregion2, member.type,
1193 case DW_TAG_subroutine_type:
1196 XBT_VERB("Unknown case: %d", type->type);
1203 static bool global_variables_differ(simgrid::mc::StateComparator& state, simgrid::mc::ObjectInformation* object_info,
1204 simgrid::mc::Region* r1, simgrid::mc::Region* r2, simgrid::mc::Snapshot* snapshot1,
1205 simgrid::mc::Snapshot* snapshot2)
1207 xbt_assert(r1 && r2, "Missing region.");
1209 std::vector<simgrid::mc::Variable>& variables = object_info->global_variables;
1211 for (simgrid::mc::Variable const& current_var : variables) {
1213 // If the variable is not in this object, skip it:
1214 // We do not expect to find a pointer to something which is not reachable
1215 // by the global variables.
1216 if ((char *) current_var.address < (char *) object_info->start_rw
1217 || (char *) current_var.address > (char *) object_info->end_rw)
1220 simgrid::mc::Type* bvariable_type = current_var.type;
1221 if (areas_differ_with_type(state, (char*)current_var.address, snapshot1, r1, (char*)current_var.address, snapshot2,
1222 r2, bvariable_type, 0)) {
1223 XBT_VERB("Global variable %s (%p) is different between snapshots",
1224 current_var.name.c_str(),
1225 (char *) current_var.address);
1233 static bool local_variables_differ(simgrid::mc::StateComparator& state, simgrid::mc::Snapshot* snapshot1,
1234 simgrid::mc::Snapshot* snapshot2, mc_snapshot_stack_t stack1,
1235 mc_snapshot_stack_t stack2)
1237 if (stack1->local_variables.size() != stack2->local_variables.size()) {
1238 XBT_VERB("Different number of local variables");
1242 for (unsigned int cursor = 0; cursor < stack1->local_variables.size(); cursor++) {
1243 local_variable_t current_var1 = &stack1->local_variables[cursor];
1244 local_variable_t current_var2 = &stack2->local_variables[cursor];
1245 if (current_var1->name != current_var2->name || current_var1->subprogram != current_var2->subprogram ||
1246 current_var1->ip != current_var2->ip) {
1247 // TODO, fix current_varX->subprogram->name to include name if DW_TAG_inlined_subprogram
1248 XBT_VERB("Different name of variable (%s - %s) "
1249 "or frame (%s - %s) or ip (%lu - %lu)",
1250 current_var1->name.c_str(), current_var2->name.c_str(), current_var1->subprogram->name.c_str(),
1251 current_var2->subprogram->name.c_str(), current_var1->ip, current_var2->ip);
1255 if (areas_differ_with_type(state, current_var1->address, snapshot1, snapshot1->get_region(current_var1->address),
1256 current_var2->address, snapshot2, snapshot2->get_region(current_var2->address),
1257 current_var1->type, 0)) {
1258 XBT_VERB("Local variable %s (%p - %p) in frame %s "
1259 "is different between snapshots",
1260 current_var1->name.c_str(), current_var1->address, current_var2->address,
1261 current_var1->subprogram->name.c_str());
1271 bool snapshot_equal(Snapshot* s1, Snapshot* s2)
1273 // TODO, make this a field of ModelChecker or something similar
1274 static StateComparator state_comparator;
1276 const RemoteClient& process = mc_model_checker->process();
1278 if (s1->hash_ != s2->hash_) {
1279 XBT_VERB("(%d - %d) Different hash: 0x%" PRIx64 "--0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_,
1283 XBT_VERB("(%d - %d) Same hash: 0x%" PRIx64, s1->num_state_, s2->num_state_, s1->hash_);
1285 /* Compare enabled processes */
1286 if (s1->enabled_processes_ != s2->enabled_processes_) {
1287 XBT_VERB("(%d - %d) Different amount of enabled processes", s1->num_state_, s2->num_state_);
1291 /* Compare size of stacks */
1292 for (unsigned long i = 0; i < s1->stacks_.size(); i++) {
1293 size_t size_used1 = s1->stack_sizes_[i];
1294 size_t size_used2 = s2->stack_sizes_[i];
1295 if (size_used1 != size_used2) {
1296 XBT_VERB("(%d - %d) Different size used in stacks: %zu - %zu", s1->num_state_, s2->num_state_, size_used1,
1302 /* Init heap information used in heap comparison algorithm */
1303 xbt_mheap_t heap1 = (xbt_mheap_t)s1->read_bytes(alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
1304 remote(process.heap_address), simgrid::mc::ReadOptions::lazy());
1305 xbt_mheap_t heap2 = (xbt_mheap_t)s2->read_bytes(alloca(sizeof(struct mdesc)), sizeof(struct mdesc),
1306 remote(process.heap_address), simgrid::mc::ReadOptions::lazy());
1307 if (state_comparator.initHeapInformation(heap1, heap2, &s1->to_ignore_, &s2->to_ignore_) == -1) {
1308 XBT_VERB("(%d - %d) Different heap information", s1->num_state_, s2->num_state_);
1312 /* Stacks comparison */
1313 for (unsigned int cursor = 0; cursor < s1->stacks_.size(); cursor++) {
1314 mc_snapshot_stack_t stack1 = &s1->stacks_[cursor];
1315 mc_snapshot_stack_t stack2 = &s2->stacks_[cursor];
1317 if (local_variables_differ(state_comparator, s1, s2, stack1, stack2)) {
1318 XBT_VERB("(%d - %d) Different local variables between stacks %u", s1->num_state_, s2->num_state_, cursor + 1);
1323 size_t regions_count = s1->snapshot_regions_.size();
1324 if (regions_count != s2->snapshot_regions_.size())
1327 for (size_t k = 0; k != regions_count; ++k) {
1328 Region* region1 = s1->snapshot_regions_[k].get();
1329 Region* region2 = s2->snapshot_regions_[k].get();
1332 if (region1->region_type() != RegionType::Data)
1335 xbt_assert(region1->region_type() == region2->region_type());
1336 xbt_assert(region1->object_info() == region2->object_info());
1337 xbt_assert(region1->object_info());
1339 /* Compare global variables */
1340 if (global_variables_differ(state_comparator, region1->object_info(), region1, region2, s1, s2)) {
1341 std::string const& name = region1->object_info()->file_name;
1342 XBT_VERB("(%d - %d) Different global variables in %s", s1->num_state_, s2->num_state_, name.c_str());
1348 if (mmalloc_heap_differ(state_comparator, s1, s2)) {
1349 XBT_VERB("(%d - %d) Different heap (mmalloc_compare)", s1->num_state_, s2->num_state_);
1353 XBT_VERB("(%d - %d) No difference found", s1->num_state_, s2->num_state_);