1 // Copyright 2012 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "src/profiler/profile-generator.h"
6
7 #include "src/ast/scopeinfo.h"
8 #include "src/base/adapters.h"
9 #include "src/debug/debug.h"
10 #include "src/deoptimizer.h"
11 #include "src/global-handles.h"
12 #include "src/profiler/cpu-profiler.h"
13 #include "src/profiler/profile-generator-inl.h"
14 #include "src/profiler/tick-sample.h"
15 #include "src/unicode.h"
16
17 namespace v8 {
18 namespace internal {
19
20
JITLineInfoTable()21 JITLineInfoTable::JITLineInfoTable() {}
22
23
~JITLineInfoTable()24 JITLineInfoTable::~JITLineInfoTable() {}
25
26
SetPosition(int pc_offset,int line)27 void JITLineInfoTable::SetPosition(int pc_offset, int line) {
28 DCHECK(pc_offset >= 0);
29 DCHECK(line > 0); // The 1-based number of the source line.
30 if (GetSourceLineNumber(pc_offset) != line) {
31 pc_offset_map_.insert(std::make_pair(pc_offset, line));
32 }
33 }
34
35
GetSourceLineNumber(int pc_offset) const36 int JITLineInfoTable::GetSourceLineNumber(int pc_offset) const {
37 PcOffsetMap::const_iterator it = pc_offset_map_.lower_bound(pc_offset);
38 if (it == pc_offset_map_.end()) {
39 if (pc_offset_map_.empty()) return v8::CpuProfileNode::kNoLineNumberInfo;
40 return (--pc_offset_map_.end())->second;
41 }
42 return it->second;
43 }
44
45
46 const char* const CodeEntry::kEmptyNamePrefix = "";
47 const char* const CodeEntry::kEmptyResourceName = "";
48 const char* const CodeEntry::kEmptyBailoutReason = "";
49 const char* const CodeEntry::kNoDeoptReason = "";
50
51 const char* const CodeEntry::kProgramEntryName = "(program)";
52 const char* const CodeEntry::kIdleEntryName = "(idle)";
53 const char* const CodeEntry::kGarbageCollectorEntryName = "(garbage collector)";
54 const char* const CodeEntry::kUnresolvedFunctionName = "(unresolved function)";
55
56 base::LazyDynamicInstance<CodeEntry, CodeEntry::ProgramEntryCreateTrait>::type
57 CodeEntry::kProgramEntry = LAZY_DYNAMIC_INSTANCE_INITIALIZER;
58
59 base::LazyDynamicInstance<CodeEntry, CodeEntry::IdleEntryCreateTrait>::type
60 CodeEntry::kIdleEntry = LAZY_DYNAMIC_INSTANCE_INITIALIZER;
61
62 base::LazyDynamicInstance<CodeEntry, CodeEntry::GCEntryCreateTrait>::type
63 CodeEntry::kGCEntry = LAZY_DYNAMIC_INSTANCE_INITIALIZER;
64
65 base::LazyDynamicInstance<CodeEntry,
66 CodeEntry::UnresolvedEntryCreateTrait>::type
67 CodeEntry::kUnresolvedEntry = LAZY_DYNAMIC_INSTANCE_INITIALIZER;
68
Create()69 CodeEntry* CodeEntry::ProgramEntryCreateTrait::Create() {
70 return new CodeEntry(Logger::FUNCTION_TAG, CodeEntry::kProgramEntryName);
71 }
72
Create()73 CodeEntry* CodeEntry::IdleEntryCreateTrait::Create() {
74 return new CodeEntry(Logger::FUNCTION_TAG, CodeEntry::kIdleEntryName);
75 }
76
Create()77 CodeEntry* CodeEntry::GCEntryCreateTrait::Create() {
78 return new CodeEntry(Logger::BUILTIN_TAG,
79 CodeEntry::kGarbageCollectorEntryName);
80 }
81
Create()82 CodeEntry* CodeEntry::UnresolvedEntryCreateTrait::Create() {
83 return new CodeEntry(Logger::FUNCTION_TAG,
84 CodeEntry::kUnresolvedFunctionName);
85 }
86
~CodeEntry()87 CodeEntry::~CodeEntry() {
88 delete line_info_;
89 for (auto location : inline_locations_) {
90 for (auto entry : location.second) {
91 delete entry;
92 }
93 }
94 }
95
96
GetHash() const97 uint32_t CodeEntry::GetHash() const {
98 uint32_t hash = ComputeIntegerHash(tag(), v8::internal::kZeroHashSeed);
99 if (script_id_ != v8::UnboundScript::kNoScriptId) {
100 hash ^= ComputeIntegerHash(static_cast<uint32_t>(script_id_),
101 v8::internal::kZeroHashSeed);
102 hash ^= ComputeIntegerHash(static_cast<uint32_t>(position_),
103 v8::internal::kZeroHashSeed);
104 } else {
105 hash ^= ComputeIntegerHash(
106 static_cast<uint32_t>(reinterpret_cast<uintptr_t>(name_prefix_)),
107 v8::internal::kZeroHashSeed);
108 hash ^= ComputeIntegerHash(
109 static_cast<uint32_t>(reinterpret_cast<uintptr_t>(name_)),
110 v8::internal::kZeroHashSeed);
111 hash ^= ComputeIntegerHash(
112 static_cast<uint32_t>(reinterpret_cast<uintptr_t>(resource_name_)),
113 v8::internal::kZeroHashSeed);
114 hash ^= ComputeIntegerHash(line_number_, v8::internal::kZeroHashSeed);
115 }
116 return hash;
117 }
118
119
IsSameFunctionAs(CodeEntry * entry) const120 bool CodeEntry::IsSameFunctionAs(CodeEntry* entry) const {
121 if (this == entry) return true;
122 if (script_id_ != v8::UnboundScript::kNoScriptId) {
123 return script_id_ == entry->script_id_ && position_ == entry->position_;
124 }
125 return name_prefix_ == entry->name_prefix_ && name_ == entry->name_ &&
126 resource_name_ == entry->resource_name_ &&
127 line_number_ == entry->line_number_;
128 }
129
130
SetBuiltinId(Builtins::Name id)131 void CodeEntry::SetBuiltinId(Builtins::Name id) {
132 bit_field_ = TagField::update(bit_field_, CodeEventListener::BUILTIN_TAG);
133 bit_field_ = BuiltinIdField::update(bit_field_, id);
134 }
135
136
GetSourceLine(int pc_offset) const137 int CodeEntry::GetSourceLine(int pc_offset) const {
138 if (line_info_ && !line_info_->empty()) {
139 return line_info_->GetSourceLineNumber(pc_offset);
140 }
141 return v8::CpuProfileNode::kNoLineNumberInfo;
142 }
143
AddInlineStack(int pc_offset,std::vector<CodeEntry * > & inline_stack)144 void CodeEntry::AddInlineStack(int pc_offset,
145 std::vector<CodeEntry*>& inline_stack) {
146 // It's better to use std::move to place the vector into the map,
147 // but it's not supported by the current stdlibc++ on MacOS.
148 inline_locations_.insert(std::make_pair(pc_offset, std::vector<CodeEntry*>()))
149 .first->second.swap(inline_stack);
150 }
151
GetInlineStack(int pc_offset) const152 const std::vector<CodeEntry*>* CodeEntry::GetInlineStack(int pc_offset) const {
153 auto it = inline_locations_.find(pc_offset);
154 return it != inline_locations_.end() ? &it->second : NULL;
155 }
156
AddDeoptInlinedFrames(int deopt_id,std::vector<DeoptInlinedFrame> & inlined_frames)157 void CodeEntry::AddDeoptInlinedFrames(
158 int deopt_id, std::vector<DeoptInlinedFrame>& inlined_frames) {
159 // It's better to use std::move to place the vector into the map,
160 // but it's not supported by the current stdlibc++ on MacOS.
161 deopt_inlined_frames_
162 .insert(std::make_pair(deopt_id, std::vector<DeoptInlinedFrame>()))
163 .first->second.swap(inlined_frames);
164 }
165
HasDeoptInlinedFramesFor(int deopt_id) const166 bool CodeEntry::HasDeoptInlinedFramesFor(int deopt_id) const {
167 return deopt_inlined_frames_.find(deopt_id) != deopt_inlined_frames_.end();
168 }
169
FillFunctionInfo(SharedFunctionInfo * shared)170 void CodeEntry::FillFunctionInfo(SharedFunctionInfo* shared) {
171 if (!shared->script()->IsScript()) return;
172 Script* script = Script::cast(shared->script());
173 set_script_id(script->id());
174 set_position(shared->start_position());
175 set_bailout_reason(GetBailoutReason(shared->disable_optimization_reason()));
176 }
177
GetDeoptInfo()178 CpuProfileDeoptInfo CodeEntry::GetDeoptInfo() {
179 DCHECK(has_deopt_info());
180
181 CpuProfileDeoptInfo info;
182 info.deopt_reason = deopt_reason_;
183 DCHECK_NE(Deoptimizer::DeoptInfo::kNoDeoptId, deopt_id_);
184 if (deopt_inlined_frames_.find(deopt_id_) == deopt_inlined_frames_.end()) {
185 info.stack.push_back(CpuProfileDeoptFrame(
186 {script_id_, position_ + deopt_position_.position()}));
187 } else {
188 size_t deopt_position = deopt_position_.raw();
189 // Copy stack of inlined frames where the deopt happened.
190 std::vector<DeoptInlinedFrame>& frames = deopt_inlined_frames_[deopt_id_];
191 for (DeoptInlinedFrame& inlined_frame : base::Reversed(frames)) {
192 info.stack.push_back(CpuProfileDeoptFrame(
193 {inlined_frame.script_id, deopt_position + inlined_frame.position}));
194 deopt_position = 0; // Done with innermost frame.
195 }
196 }
197 return info;
198 }
199
200
CollectDeoptInfo(CodeEntry * entry)201 void ProfileNode::CollectDeoptInfo(CodeEntry* entry) {
202 deopt_infos_.push_back(entry->GetDeoptInfo());
203 entry->clear_deopt_info();
204 }
205
206
FindChild(CodeEntry * entry)207 ProfileNode* ProfileNode::FindChild(CodeEntry* entry) {
208 base::HashMap::Entry* map_entry =
209 children_.Lookup(entry, CodeEntryHash(entry));
210 return map_entry != NULL ?
211 reinterpret_cast<ProfileNode*>(map_entry->value) : NULL;
212 }
213
214
FindOrAddChild(CodeEntry * entry)215 ProfileNode* ProfileNode::FindOrAddChild(CodeEntry* entry) {
216 base::HashMap::Entry* map_entry =
217 children_.LookupOrInsert(entry, CodeEntryHash(entry));
218 ProfileNode* node = reinterpret_cast<ProfileNode*>(map_entry->value);
219 if (node == NULL) {
220 // New node added.
221 node = new ProfileNode(tree_, entry);
222 map_entry->value = node;
223 children_list_.Add(node);
224 }
225 return node;
226 }
227
228
IncrementLineTicks(int src_line)229 void ProfileNode::IncrementLineTicks(int src_line) {
230 if (src_line == v8::CpuProfileNode::kNoLineNumberInfo) return;
231 // Increment a hit counter of a certain source line.
232 // Add a new source line if not found.
233 base::HashMap::Entry* e =
234 line_ticks_.LookupOrInsert(reinterpret_cast<void*>(src_line), src_line);
235 DCHECK(e);
236 e->value = reinterpret_cast<void*>(reinterpret_cast<uintptr_t>(e->value) + 1);
237 }
238
239
GetLineTicks(v8::CpuProfileNode::LineTick * entries,unsigned int length) const240 bool ProfileNode::GetLineTicks(v8::CpuProfileNode::LineTick* entries,
241 unsigned int length) const {
242 if (entries == NULL || length == 0) return false;
243
244 unsigned line_count = line_ticks_.occupancy();
245
246 if (line_count == 0) return true;
247 if (length < line_count) return false;
248
249 v8::CpuProfileNode::LineTick* entry = entries;
250
251 for (base::HashMap::Entry *p = line_ticks_.Start(); p != NULL;
252 p = line_ticks_.Next(p), entry++) {
253 entry->line =
254 static_cast<unsigned int>(reinterpret_cast<uintptr_t>(p->key));
255 entry->hit_count =
256 static_cast<unsigned int>(reinterpret_cast<uintptr_t>(p->value));
257 }
258
259 return true;
260 }
261
262
Print(int indent)263 void ProfileNode::Print(int indent) {
264 base::OS::Print("%5u %*s %s%s %d #%d", self_ticks_, indent, "",
265 entry_->name_prefix(), entry_->name(), entry_->script_id(),
266 id());
267 if (entry_->resource_name()[0] != '\0')
268 base::OS::Print(" %s:%d", entry_->resource_name(), entry_->line_number());
269 base::OS::Print("\n");
270 for (size_t i = 0; i < deopt_infos_.size(); ++i) {
271 CpuProfileDeoptInfo& info = deopt_infos_[i];
272 base::OS::Print("%*s;;; deopted at script_id: %d position: %" PRIuS
273 " with reason '%s'.\n",
274 indent + 10, "", info.stack[0].script_id,
275 info.stack[0].position, info.deopt_reason);
276 for (size_t index = 1; index < info.stack.size(); ++index) {
277 base::OS::Print("%*s;;; Inline point: script_id %d position: %" PRIuS
278 ".\n",
279 indent + 10, "", info.stack[index].script_id,
280 info.stack[index].position);
281 }
282 }
283 const char* bailout_reason = entry_->bailout_reason();
284 if (bailout_reason != GetBailoutReason(BailoutReason::kNoReason) &&
285 bailout_reason != CodeEntry::kEmptyBailoutReason) {
286 base::OS::Print("%*s bailed out due to '%s'\n", indent + 10, "",
287 bailout_reason);
288 }
289 for (base::HashMap::Entry* p = children_.Start(); p != NULL;
290 p = children_.Next(p)) {
291 reinterpret_cast<ProfileNode*>(p->value)->Print(indent + 2);
292 }
293 }
294
295
296 class DeleteNodesCallback {
297 public:
BeforeTraversingChild(ProfileNode *,ProfileNode *)298 void BeforeTraversingChild(ProfileNode*, ProfileNode*) { }
299
AfterAllChildrenTraversed(ProfileNode * node)300 void AfterAllChildrenTraversed(ProfileNode* node) {
301 delete node;
302 }
303
AfterChildTraversed(ProfileNode *,ProfileNode *)304 void AfterChildTraversed(ProfileNode*, ProfileNode*) { }
305 };
306
ProfileTree(Isolate * isolate)307 ProfileTree::ProfileTree(Isolate* isolate)
308 : root_entry_(CodeEventListener::FUNCTION_TAG, "(root)"),
309 next_node_id_(1),
310 root_(new ProfileNode(this, &root_entry_)),
311 isolate_(isolate),
312 next_function_id_(1),
313 function_ids_(ProfileNode::CodeEntriesMatch) {}
314
~ProfileTree()315 ProfileTree::~ProfileTree() {
316 DeleteNodesCallback cb;
317 TraverseDepthFirst(&cb);
318 }
319
320
GetFunctionId(const ProfileNode * node)321 unsigned ProfileTree::GetFunctionId(const ProfileNode* node) {
322 CodeEntry* code_entry = node->entry();
323 base::HashMap::Entry* entry =
324 function_ids_.LookupOrInsert(code_entry, code_entry->GetHash());
325 if (!entry->value) {
326 entry->value = reinterpret_cast<void*>(next_function_id_++);
327 }
328 return static_cast<unsigned>(reinterpret_cast<uintptr_t>(entry->value));
329 }
330
AddPathFromEnd(const std::vector<CodeEntry * > & path,int src_line,bool update_stats)331 ProfileNode* ProfileTree::AddPathFromEnd(const std::vector<CodeEntry*>& path,
332 int src_line, bool update_stats) {
333 ProfileNode* node = root_;
334 CodeEntry* last_entry = NULL;
335 for (auto it = path.rbegin(); it != path.rend(); ++it) {
336 if (*it == NULL) continue;
337 last_entry = *it;
338 node = node->FindOrAddChild(*it);
339 }
340 if (last_entry && last_entry->has_deopt_info()) {
341 node->CollectDeoptInfo(last_entry);
342 }
343 if (update_stats) {
344 node->IncrementSelfTicks();
345 if (src_line != v8::CpuProfileNode::kNoLineNumberInfo) {
346 node->IncrementLineTicks(src_line);
347 }
348 }
349 return node;
350 }
351
352
353 struct NodesPair {
NodesPairv8::internal::NodesPair354 NodesPair(ProfileNode* src, ProfileNode* dst)
355 : src(src), dst(dst) { }
356 ProfileNode* src;
357 ProfileNode* dst;
358 };
359
360
361 class Position {
362 public:
Position(ProfileNode * node)363 explicit Position(ProfileNode* node)
364 : node(node), child_idx_(0) { }
INLINE(ProfileNode * current_child ())365 INLINE(ProfileNode* current_child()) {
366 return node->children()->at(child_idx_);
367 }
INLINE(bool has_current_child ())368 INLINE(bool has_current_child()) {
369 return child_idx_ < node->children()->length();
370 }
INLINE(void next_child ())371 INLINE(void next_child()) { ++child_idx_; }
372
373 ProfileNode* node;
374 private:
375 int child_idx_;
376 };
377
378
379 // Non-recursive implementation of a depth-first post-order tree traversal.
380 template <typename Callback>
TraverseDepthFirst(Callback * callback)381 void ProfileTree::TraverseDepthFirst(Callback* callback) {
382 List<Position> stack(10);
383 stack.Add(Position(root_));
384 while (stack.length() > 0) {
385 Position& current = stack.last();
386 if (current.has_current_child()) {
387 callback->BeforeTraversingChild(current.node, current.current_child());
388 stack.Add(Position(current.current_child()));
389 } else {
390 callback->AfterAllChildrenTraversed(current.node);
391 if (stack.length() > 1) {
392 Position& parent = stack[stack.length() - 2];
393 callback->AfterChildTraversed(parent.node, current.node);
394 parent.next_child();
395 }
396 // Remove child from the stack.
397 stack.RemoveLast();
398 }
399 }
400 }
401
CpuProfile(CpuProfiler * profiler,const char * title,bool record_samples)402 CpuProfile::CpuProfile(CpuProfiler* profiler, const char* title,
403 bool record_samples)
404 : title_(title),
405 record_samples_(record_samples),
406 start_time_(base::TimeTicks::HighResolutionNow()),
407 top_down_(profiler->isolate()),
408 profiler_(profiler) {}
409
AddPath(base::TimeTicks timestamp,const std::vector<CodeEntry * > & path,int src_line,bool update_stats)410 void CpuProfile::AddPath(base::TimeTicks timestamp,
411 const std::vector<CodeEntry*>& path, int src_line,
412 bool update_stats) {
413 ProfileNode* top_frame_node =
414 top_down_.AddPathFromEnd(path, src_line, update_stats);
415 if (record_samples_ && !timestamp.IsNull()) {
416 timestamps_.Add(timestamp);
417 samples_.Add(top_frame_node);
418 }
419 }
420
CalculateTotalTicksAndSamplingRate()421 void CpuProfile::CalculateTotalTicksAndSamplingRate() {
422 end_time_ = base::TimeTicks::HighResolutionNow();
423 }
424
Print()425 void CpuProfile::Print() {
426 base::OS::Print("[Top down]:\n");
427 top_down_.Print();
428 }
429
AddCode(Address addr,CodeEntry * entry,unsigned size)430 void CodeMap::AddCode(Address addr, CodeEntry* entry, unsigned size) {
431 DeleteAllCoveredCode(addr, addr + size);
432 code_map_.insert({addr, CodeEntryInfo(entry, size)});
433 }
434
DeleteAllCoveredCode(Address start,Address end)435 void CodeMap::DeleteAllCoveredCode(Address start, Address end) {
436 auto left = code_map_.upper_bound(start);
437 if (left != code_map_.begin()) {
438 --left;
439 if (left->first + left->second.size <= start) ++left;
440 }
441 auto right = left;
442 while (right != code_map_.end() && right->first < end) ++right;
443 code_map_.erase(left, right);
444 }
445
FindEntry(Address addr)446 CodeEntry* CodeMap::FindEntry(Address addr) {
447 auto it = code_map_.upper_bound(addr);
448 if (it == code_map_.begin()) return nullptr;
449 --it;
450 Address end_address = it->first + it->second.size;
451 return addr < end_address ? it->second.entry : nullptr;
452 }
453
MoveCode(Address from,Address to)454 void CodeMap::MoveCode(Address from, Address to) {
455 if (from == to) return;
456 auto it = code_map_.find(from);
457 if (it == code_map_.end()) return;
458 CodeEntryInfo info = it->second;
459 code_map_.erase(it);
460 AddCode(to, info.entry, info.size);
461 }
462
Print()463 void CodeMap::Print() {
464 for (auto it = code_map_.begin(); it != code_map_.end(); ++it) {
465 base::OS::Print("%p %5d %s\n", static_cast<void*>(it->first),
466 it->second.size, it->second.entry->name());
467 }
468 }
469
CpuProfilesCollection(Isolate * isolate)470 CpuProfilesCollection::CpuProfilesCollection(Isolate* isolate)
471 : resource_names_(isolate->heap()),
472 profiler_(nullptr),
473 current_profiles_semaphore_(1) {}
474
DeleteCpuProfile(CpuProfile ** profile_ptr)475 static void DeleteCpuProfile(CpuProfile** profile_ptr) {
476 delete *profile_ptr;
477 }
478
479
~CpuProfilesCollection()480 CpuProfilesCollection::~CpuProfilesCollection() {
481 finished_profiles_.Iterate(DeleteCpuProfile);
482 current_profiles_.Iterate(DeleteCpuProfile);
483 }
484
485
StartProfiling(const char * title,bool record_samples)486 bool CpuProfilesCollection::StartProfiling(const char* title,
487 bool record_samples) {
488 current_profiles_semaphore_.Wait();
489 if (current_profiles_.length() >= kMaxSimultaneousProfiles) {
490 current_profiles_semaphore_.Signal();
491 return false;
492 }
493 for (int i = 0; i < current_profiles_.length(); ++i) {
494 if (strcmp(current_profiles_[i]->title(), title) == 0) {
495 // Ignore attempts to start profile with the same title...
496 current_profiles_semaphore_.Signal();
497 // ... though return true to force it collect a sample.
498 return true;
499 }
500 }
501 current_profiles_.Add(new CpuProfile(profiler_, title, record_samples));
502 current_profiles_semaphore_.Signal();
503 return true;
504 }
505
506
StopProfiling(const char * title)507 CpuProfile* CpuProfilesCollection::StopProfiling(const char* title) {
508 const int title_len = StrLength(title);
509 CpuProfile* profile = NULL;
510 current_profiles_semaphore_.Wait();
511 for (int i = current_profiles_.length() - 1; i >= 0; --i) {
512 if (title_len == 0 || strcmp(current_profiles_[i]->title(), title) == 0) {
513 profile = current_profiles_.Remove(i);
514 break;
515 }
516 }
517 current_profiles_semaphore_.Signal();
518
519 if (profile == NULL) return NULL;
520 profile->CalculateTotalTicksAndSamplingRate();
521 finished_profiles_.Add(profile);
522 return profile;
523 }
524
525
IsLastProfile(const char * title)526 bool CpuProfilesCollection::IsLastProfile(const char* title) {
527 // Called from VM thread, and only it can mutate the list,
528 // so no locking is needed here.
529 if (current_profiles_.length() != 1) return false;
530 return StrLength(title) == 0
531 || strcmp(current_profiles_[0]->title(), title) == 0;
532 }
533
534
RemoveProfile(CpuProfile * profile)535 void CpuProfilesCollection::RemoveProfile(CpuProfile* profile) {
536 // Called from VM thread for a completed profile.
537 for (int i = 0; i < finished_profiles_.length(); i++) {
538 if (profile == finished_profiles_[i]) {
539 finished_profiles_.Remove(i);
540 return;
541 }
542 }
543 UNREACHABLE();
544 }
545
AddPathToCurrentProfiles(base::TimeTicks timestamp,const std::vector<CodeEntry * > & path,int src_line,bool update_stats)546 void CpuProfilesCollection::AddPathToCurrentProfiles(
547 base::TimeTicks timestamp, const std::vector<CodeEntry*>& path,
548 int src_line, bool update_stats) {
549 // As starting / stopping profiles is rare relatively to this
550 // method, we don't bother minimizing the duration of lock holding,
551 // e.g. copying contents of the list to a local vector.
552 current_profiles_semaphore_.Wait();
553 for (int i = 0; i < current_profiles_.length(); ++i) {
554 current_profiles_[i]->AddPath(timestamp, path, src_line, update_stats);
555 }
556 current_profiles_semaphore_.Signal();
557 }
558
ProfileGenerator(CpuProfilesCollection * profiles)559 ProfileGenerator::ProfileGenerator(CpuProfilesCollection* profiles)
560 : profiles_(profiles) {}
561
RecordTickSample(const TickSample & sample)562 void ProfileGenerator::RecordTickSample(const TickSample& sample) {
563 std::vector<CodeEntry*> entries;
564 // Conservatively reserve space for stack frames + pc + function + vm-state.
565 // There could in fact be more of them because of inlined entries.
566 entries.reserve(sample.frames_count + 3);
567
568 // The ProfileNode knows nothing about all versions of generated code for
569 // the same JS function. The line number information associated with
570 // the latest version of generated code is used to find a source line number
571 // for a JS function. Then, the detected source line is passed to
572 // ProfileNode to increase the tick count for this source line.
573 int src_line = v8::CpuProfileNode::kNoLineNumberInfo;
574 bool src_line_not_found = true;
575
576 if (sample.pc != nullptr) {
577 if (sample.has_external_callback && sample.state == EXTERNAL) {
578 // Don't use PC when in external callback code, as it can point
579 // inside callback's code, and we will erroneously report
580 // that a callback calls itself.
581 entries.push_back(code_map_.FindEntry(sample.external_callback_entry));
582 } else {
583 CodeEntry* pc_entry = code_map_.FindEntry(sample.pc);
584 // If there is no pc_entry we're likely in native code.
585 // Find out, if top of stack was pointing inside a JS function
586 // meaning that we have encountered a frameless invocation.
587 if (!pc_entry && !sample.has_external_callback) {
588 pc_entry = code_map_.FindEntry(sample.tos);
589 }
590 // If pc is in the function code before it set up stack frame or after the
591 // frame was destroyed SafeStackFrameIterator incorrectly thinks that
592 // ebp contains return address of the current function and skips caller's
593 // frame. Check for this case and just skip such samples.
594 if (pc_entry) {
595 int pc_offset =
596 static_cast<int>(sample.pc - pc_entry->instruction_start());
597 src_line = pc_entry->GetSourceLine(pc_offset);
598 if (src_line == v8::CpuProfileNode::kNoLineNumberInfo) {
599 src_line = pc_entry->line_number();
600 }
601 src_line_not_found = false;
602 entries.push_back(pc_entry);
603
604 if (pc_entry->builtin_id() == Builtins::kFunctionPrototypeApply ||
605 pc_entry->builtin_id() == Builtins::kFunctionPrototypeCall) {
606 // When current function is either the Function.prototype.apply or the
607 // Function.prototype.call builtin the top frame is either frame of
608 // the calling JS function or internal frame.
609 // In the latter case we know the caller for sure but in the
610 // former case we don't so we simply replace the frame with
611 // 'unresolved' entry.
612 if (!sample.has_external_callback) {
613 entries.push_back(CodeEntry::unresolved_entry());
614 }
615 }
616 }
617 }
618
619 for (const Address *stack_pos = sample.stack,
620 *stack_end = stack_pos + sample.frames_count;
621 stack_pos != stack_end; ++stack_pos) {
622 CodeEntry* entry = code_map_.FindEntry(*stack_pos);
623
624 if (entry) {
625 // Find out if the entry has an inlining stack associated.
626 int pc_offset =
627 static_cast<int>(*stack_pos - entry->instruction_start());
628 const std::vector<CodeEntry*>* inline_stack =
629 entry->GetInlineStack(pc_offset);
630 if (inline_stack) {
631 entries.insert(entries.end(), inline_stack->rbegin(),
632 inline_stack->rend());
633 }
634 // Skip unresolved frames (e.g. internal frame) and get source line of
635 // the first JS caller.
636 if (src_line_not_found) {
637 src_line = entry->GetSourceLine(pc_offset);
638 if (src_line == v8::CpuProfileNode::kNoLineNumberInfo) {
639 src_line = entry->line_number();
640 }
641 src_line_not_found = false;
642 }
643 }
644 entries.push_back(entry);
645 }
646 }
647
648 if (FLAG_prof_browser_mode) {
649 bool no_symbolized_entries = true;
650 for (auto e : entries) {
651 if (e != NULL) {
652 no_symbolized_entries = false;
653 break;
654 }
655 }
656 // If no frames were symbolized, put the VM state entry in.
657 if (no_symbolized_entries) {
658 entries.push_back(EntryForVMState(sample.state));
659 }
660 }
661
662 profiles_->AddPathToCurrentProfiles(sample.timestamp, entries, src_line,
663 sample.update_stats);
664 }
665
666
EntryForVMState(StateTag tag)667 CodeEntry* ProfileGenerator::EntryForVMState(StateTag tag) {
668 switch (tag) {
669 case GC:
670 return CodeEntry::gc_entry();
671 case JS:
672 case COMPILER:
673 // DOM events handlers are reported as OTHER / EXTERNAL entries.
674 // To avoid confusing people, let's put all these entries into
675 // one bucket.
676 case OTHER:
677 case EXTERNAL:
678 return CodeEntry::program_entry();
679 case IDLE:
680 return CodeEntry::idle_entry();
681 default: return NULL;
682 }
683 }
684
685 } // namespace internal
686 } // namespace v8
687