1 /*
2 * Copyright 2014 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 #include "jit.h"
18
19 #include <dlfcn.h>
20
21 #include "art_method-inl.h"
22 #include "debugger.h"
23 #include "entrypoints/runtime_asm_entrypoints.h"
24 #include "interpreter/interpreter.h"
25 #include "jit_code_cache.h"
26 #include "oat_file_manager.h"
27 #include "oat_quick_method_header.h"
28 #include "offline_profiling_info.h"
29 #include "profile_saver.h"
30 #include "runtime.h"
31 #include "runtime_options.h"
32 #include "stack_map.h"
33 #include "thread_list.h"
34 #include "utils.h"
35
36 namespace art {
37 namespace jit {
38
39 static constexpr bool kEnableOnStackReplacement = true;
40 // At what priority to schedule jit threads. 9 is the lowest foreground priority on device.
41 static constexpr int kJitPoolThreadPthreadPriority = 9;
42
43 // JIT compiler
44 void* Jit::jit_library_handle_= nullptr;
45 void* Jit::jit_compiler_handle_ = nullptr;
46 void* (*Jit::jit_load_)(bool*) = nullptr;
47 void (*Jit::jit_unload_)(void*) = nullptr;
48 bool (*Jit::jit_compile_method_)(void*, ArtMethod*, Thread*, bool) = nullptr;
49 void (*Jit::jit_types_loaded_)(void*, mirror::Class**, size_t count) = nullptr;
50 bool Jit::generate_debug_info_ = false;
51
CreateFromRuntimeArguments(const RuntimeArgumentMap & options)52 JitOptions* JitOptions::CreateFromRuntimeArguments(const RuntimeArgumentMap& options) {
53 auto* jit_options = new JitOptions;
54 jit_options->use_jit_compilation_ = options.GetOrDefault(RuntimeArgumentMap::UseJitCompilation);
55
56 jit_options->code_cache_initial_capacity_ =
57 options.GetOrDefault(RuntimeArgumentMap::JITCodeCacheInitialCapacity);
58 jit_options->code_cache_max_capacity_ =
59 options.GetOrDefault(RuntimeArgumentMap::JITCodeCacheMaxCapacity);
60 jit_options->dump_info_on_shutdown_ =
61 options.Exists(RuntimeArgumentMap::DumpJITInfoOnShutdown);
62 jit_options->save_profiling_info_ =
63 options.GetOrDefault(RuntimeArgumentMap::JITSaveProfilingInfo);
64
65 jit_options->compile_threshold_ = options.GetOrDefault(RuntimeArgumentMap::JITCompileThreshold);
66 if (jit_options->compile_threshold_ > std::numeric_limits<uint16_t>::max()) {
67 LOG(FATAL) << "Method compilation threshold is above its internal limit.";
68 }
69
70 if (options.Exists(RuntimeArgumentMap::JITWarmupThreshold)) {
71 jit_options->warmup_threshold_ = *options.Get(RuntimeArgumentMap::JITWarmupThreshold);
72 if (jit_options->warmup_threshold_ > std::numeric_limits<uint16_t>::max()) {
73 LOG(FATAL) << "Method warmup threshold is above its internal limit.";
74 }
75 } else {
76 jit_options->warmup_threshold_ = jit_options->compile_threshold_ / 2;
77 }
78
79 if (options.Exists(RuntimeArgumentMap::JITOsrThreshold)) {
80 jit_options->osr_threshold_ = *options.Get(RuntimeArgumentMap::JITOsrThreshold);
81 if (jit_options->osr_threshold_ > std::numeric_limits<uint16_t>::max()) {
82 LOG(FATAL) << "Method on stack replacement threshold is above its internal limit.";
83 }
84 } else {
85 jit_options->osr_threshold_ = jit_options->compile_threshold_ * 2;
86 if (jit_options->osr_threshold_ > std::numeric_limits<uint16_t>::max()) {
87 jit_options->osr_threshold_ = std::numeric_limits<uint16_t>::max();
88 }
89 }
90
91 if (options.Exists(RuntimeArgumentMap::JITPriorityThreadWeight)) {
92 jit_options->priority_thread_weight_ =
93 *options.Get(RuntimeArgumentMap::JITPriorityThreadWeight);
94 if (jit_options->priority_thread_weight_ > jit_options->warmup_threshold_) {
95 LOG(FATAL) << "Priority thread weight is above the warmup threshold.";
96 } else if (jit_options->priority_thread_weight_ == 0) {
97 LOG(FATAL) << "Priority thread weight cannot be 0.";
98 }
99 } else {
100 jit_options->priority_thread_weight_ = std::max(
101 jit_options->warmup_threshold_ / Jit::kDefaultPriorityThreadWeightRatio,
102 static_cast<size_t>(1));
103 }
104
105 if (options.Exists(RuntimeArgumentMap::JITInvokeTransitionWeight)) {
106 jit_options->invoke_transition_weight_ =
107 *options.Get(RuntimeArgumentMap::JITInvokeTransitionWeight);
108 if (jit_options->invoke_transition_weight_ > jit_options->warmup_threshold_) {
109 LOG(FATAL) << "Invoke transition weight is above the warmup threshold.";
110 } else if (jit_options->invoke_transition_weight_ == 0) {
111 LOG(FATAL) << "Invoke transition weight cannot be 0.";
112 }
113 } else {
114 jit_options->invoke_transition_weight_ = std::max(
115 jit_options->warmup_threshold_ / Jit::kDefaultInvokeTransitionWeightRatio,
116 static_cast<size_t>(1));;
117 }
118
119 return jit_options;
120 }
121
ShouldUsePriorityThreadWeight()122 bool Jit::ShouldUsePriorityThreadWeight() {
123 return Runtime::Current()->InJankPerceptibleProcessState()
124 && Thread::Current()->IsJitSensitiveThread();
125 }
126
DumpInfo(std::ostream & os)127 void Jit::DumpInfo(std::ostream& os) {
128 code_cache_->Dump(os);
129 cumulative_timings_.Dump(os);
130 MutexLock mu(Thread::Current(), lock_);
131 memory_use_.PrintMemoryUse(os);
132 }
133
DumpForSigQuit(std::ostream & os)134 void Jit::DumpForSigQuit(std::ostream& os) {
135 DumpInfo(os);
136 ProfileSaver::DumpInstanceInfo(os);
137 }
138
AddTimingLogger(const TimingLogger & logger)139 void Jit::AddTimingLogger(const TimingLogger& logger) {
140 cumulative_timings_.AddLogger(logger);
141 }
142
Jit()143 Jit::Jit() : dump_info_on_shutdown_(false),
144 cumulative_timings_("JIT timings"),
145 memory_use_("Memory used for compilation", 16),
146 lock_("JIT memory use lock"),
147 use_jit_compilation_(true),
148 save_profiling_info_(false),
149 hot_method_threshold_(0),
150 warm_method_threshold_(0),
151 osr_method_threshold_(0),
152 priority_thread_weight_(0),
153 invoke_transition_weight_(0) {}
154
Create(JitOptions * options,std::string * error_msg)155 Jit* Jit::Create(JitOptions* options, std::string* error_msg) {
156 DCHECK(options->UseJitCompilation() || options->GetSaveProfilingInfo());
157 std::unique_ptr<Jit> jit(new Jit);
158 jit->dump_info_on_shutdown_ = options->DumpJitInfoOnShutdown();
159 if (jit_compiler_handle_ == nullptr && !LoadCompiler(error_msg)) {
160 return nullptr;
161 }
162 jit->code_cache_.reset(JitCodeCache::Create(
163 options->GetCodeCacheInitialCapacity(),
164 options->GetCodeCacheMaxCapacity(),
165 jit->generate_debug_info_,
166 error_msg));
167 if (jit->GetCodeCache() == nullptr) {
168 return nullptr;
169 }
170 jit->use_jit_compilation_ = options->UseJitCompilation();
171 jit->save_profiling_info_ = options->GetSaveProfilingInfo();
172 VLOG(jit) << "JIT created with initial_capacity="
173 << PrettySize(options->GetCodeCacheInitialCapacity())
174 << ", max_capacity=" << PrettySize(options->GetCodeCacheMaxCapacity())
175 << ", compile_threshold=" << options->GetCompileThreshold()
176 << ", save_profiling_info=" << options->GetSaveProfilingInfo();
177
178
179 jit->hot_method_threshold_ = options->GetCompileThreshold();
180 jit->warm_method_threshold_ = options->GetWarmupThreshold();
181 jit->osr_method_threshold_ = options->GetOsrThreshold();
182 jit->priority_thread_weight_ = options->GetPriorityThreadWeight();
183 jit->invoke_transition_weight_ = options->GetInvokeTransitionWeight();
184
185 jit->CreateThreadPool();
186
187 // Notify native debugger about the classes already loaded before the creation of the jit.
188 jit->DumpTypeInfoForLoadedTypes(Runtime::Current()->GetClassLinker());
189 return jit.release();
190 }
191
LoadCompilerLibrary(std::string * error_msg)192 bool Jit::LoadCompilerLibrary(std::string* error_msg) {
193 jit_library_handle_ = dlopen(
194 kIsDebugBuild ? "libartd-compiler.so" : "libart-compiler.so", RTLD_NOW);
195 if (jit_library_handle_ == nullptr) {
196 std::ostringstream oss;
197 oss << "JIT could not load libart-compiler.so: " << dlerror();
198 *error_msg = oss.str();
199 return false;
200 }
201 jit_load_ = reinterpret_cast<void* (*)(bool*)>(dlsym(jit_library_handle_, "jit_load"));
202 if (jit_load_ == nullptr) {
203 dlclose(jit_library_handle_);
204 *error_msg = "JIT couldn't find jit_load entry point";
205 return false;
206 }
207 jit_unload_ = reinterpret_cast<void (*)(void*)>(
208 dlsym(jit_library_handle_, "jit_unload"));
209 if (jit_unload_ == nullptr) {
210 dlclose(jit_library_handle_);
211 *error_msg = "JIT couldn't find jit_unload entry point";
212 return false;
213 }
214 jit_compile_method_ = reinterpret_cast<bool (*)(void*, ArtMethod*, Thread*, bool)>(
215 dlsym(jit_library_handle_, "jit_compile_method"));
216 if (jit_compile_method_ == nullptr) {
217 dlclose(jit_library_handle_);
218 *error_msg = "JIT couldn't find jit_compile_method entry point";
219 return false;
220 }
221 jit_types_loaded_ = reinterpret_cast<void (*)(void*, mirror::Class**, size_t)>(
222 dlsym(jit_library_handle_, "jit_types_loaded"));
223 if (jit_types_loaded_ == nullptr) {
224 dlclose(jit_library_handle_);
225 *error_msg = "JIT couldn't find jit_types_loaded entry point";
226 return false;
227 }
228 return true;
229 }
230
LoadCompiler(std::string * error_msg)231 bool Jit::LoadCompiler(std::string* error_msg) {
232 if (jit_library_handle_ == nullptr && !LoadCompilerLibrary(error_msg)) {
233 return false;
234 }
235 bool will_generate_debug_symbols = false;
236 VLOG(jit) << "Calling JitLoad interpreter_only="
237 << Runtime::Current()->GetInstrumentation()->InterpretOnly();
238 jit_compiler_handle_ = (jit_load_)(&will_generate_debug_symbols);
239 if (jit_compiler_handle_ == nullptr) {
240 dlclose(jit_library_handle_);
241 *error_msg = "JIT couldn't load compiler";
242 return false;
243 }
244 generate_debug_info_ = will_generate_debug_symbols;
245 return true;
246 }
247
CompileMethod(ArtMethod * method,Thread * self,bool osr)248 bool Jit::CompileMethod(ArtMethod* method, Thread* self, bool osr) {
249 DCHECK(Runtime::Current()->UseJitCompilation());
250 DCHECK(!method->IsRuntimeMethod());
251
252 // Don't compile the method if it has breakpoints.
253 if (Dbg::IsDebuggerActive() && Dbg::MethodHasAnyBreakpoints(method)) {
254 VLOG(jit) << "JIT not compiling " << PrettyMethod(method) << " due to breakpoint";
255 return false;
256 }
257
258 // Don't compile the method if we are supposed to be deoptimized.
259 instrumentation::Instrumentation* instrumentation = Runtime::Current()->GetInstrumentation();
260 if (instrumentation->AreAllMethodsDeoptimized() || instrumentation->IsDeoptimized(method)) {
261 VLOG(jit) << "JIT not compiling " << PrettyMethod(method) << " due to deoptimization";
262 return false;
263 }
264
265 // If we get a request to compile a proxy method, we pass the actual Java method
266 // of that proxy method, as the compiler does not expect a proxy method.
267 ArtMethod* method_to_compile = method->GetInterfaceMethodIfProxy(sizeof(void*));
268 if (!code_cache_->NotifyCompilationOf(method_to_compile, self, osr)) {
269 return false;
270 }
271
272 VLOG(jit) << "Compiling method "
273 << PrettyMethod(method_to_compile)
274 << " osr=" << std::boolalpha << osr;
275 bool success = jit_compile_method_(jit_compiler_handle_, method_to_compile, self, osr);
276 code_cache_->DoneCompiling(method_to_compile, self, osr);
277 if (!success) {
278 VLOG(jit) << "Failed to compile method "
279 << PrettyMethod(method_to_compile)
280 << " osr=" << std::boolalpha << osr;
281 }
282 return success;
283 }
284
CreateThreadPool()285 void Jit::CreateThreadPool() {
286 // There is a DCHECK in the 'AddSamples' method to ensure the tread pool
287 // is not null when we instrument.
288
289 // We need peers as we may report the JIT thread, e.g., in the debugger.
290 constexpr bool kJitPoolNeedsPeers = true;
291 thread_pool_.reset(new ThreadPool("Jit thread pool", 1, kJitPoolNeedsPeers));
292
293 thread_pool_->SetPthreadPriority(kJitPoolThreadPthreadPriority);
294 thread_pool_->StartWorkers(Thread::Current());
295 }
296
DeleteThreadPool()297 void Jit::DeleteThreadPool() {
298 Thread* self = Thread::Current();
299 DCHECK(Runtime::Current()->IsShuttingDown(self));
300 if (thread_pool_ != nullptr) {
301 ThreadPool* cache = nullptr;
302 {
303 ScopedSuspendAll ssa(__FUNCTION__);
304 // Clear thread_pool_ field while the threads are suspended.
305 // A mutator in the 'AddSamples' method will check against it.
306 cache = thread_pool_.release();
307 }
308 cache->StopWorkers(self);
309 cache->RemoveAllTasks(self);
310 // We could just suspend all threads, but we know those threads
311 // will finish in a short period, so it's not worth adding a suspend logic
312 // here. Besides, this is only done for shutdown.
313 cache->Wait(self, false, false);
314 delete cache;
315 }
316 }
317
StartProfileSaver(const std::string & filename,const std::vector<std::string> & code_paths,const std::string & foreign_dex_profile_path,const std::string & app_dir)318 void Jit::StartProfileSaver(const std::string& filename,
319 const std::vector<std::string>& code_paths,
320 const std::string& foreign_dex_profile_path,
321 const std::string& app_dir) {
322 if (save_profiling_info_) {
323 ProfileSaver::Start(filename, code_cache_.get(), code_paths, foreign_dex_profile_path, app_dir);
324 }
325 }
326
StopProfileSaver()327 void Jit::StopProfileSaver() {
328 if (save_profiling_info_ && ProfileSaver::IsStarted()) {
329 ProfileSaver::Stop(dump_info_on_shutdown_);
330 }
331 }
332
JitAtFirstUse()333 bool Jit::JitAtFirstUse() {
334 return HotMethodThreshold() == 0;
335 }
336
CanInvokeCompiledCode(ArtMethod * method)337 bool Jit::CanInvokeCompiledCode(ArtMethod* method) {
338 return code_cache_->ContainsPc(method->GetEntryPointFromQuickCompiledCode());
339 }
340
~Jit()341 Jit::~Jit() {
342 DCHECK(!save_profiling_info_ || !ProfileSaver::IsStarted());
343 if (dump_info_on_shutdown_) {
344 DumpInfo(LOG(INFO));
345 }
346 DeleteThreadPool();
347 if (jit_compiler_handle_ != nullptr) {
348 jit_unload_(jit_compiler_handle_);
349 jit_compiler_handle_ = nullptr;
350 }
351 if (jit_library_handle_ != nullptr) {
352 dlclose(jit_library_handle_);
353 jit_library_handle_ = nullptr;
354 }
355 }
356
NewTypeLoadedIfUsingJit(mirror::Class * type)357 void Jit::NewTypeLoadedIfUsingJit(mirror::Class* type) {
358 if (!Runtime::Current()->UseJitCompilation()) {
359 // No need to notify if we only use the JIT to save profiles.
360 return;
361 }
362 jit::Jit* jit = Runtime::Current()->GetJit();
363 if (jit->generate_debug_info_) {
364 DCHECK(jit->jit_types_loaded_ != nullptr);
365 jit->jit_types_loaded_(jit->jit_compiler_handle_, &type, 1);
366 }
367 }
368
DumpTypeInfoForLoadedTypes(ClassLinker * linker)369 void Jit::DumpTypeInfoForLoadedTypes(ClassLinker* linker) {
370 struct CollectClasses : public ClassVisitor {
371 bool operator()(mirror::Class* klass) override {
372 classes_.push_back(klass);
373 return true;
374 }
375 std::vector<mirror::Class*> classes_;
376 };
377
378 if (generate_debug_info_) {
379 ScopedObjectAccess so(Thread::Current());
380
381 CollectClasses visitor;
382 linker->VisitClasses(&visitor);
383 jit_types_loaded_(jit_compiler_handle_, visitor.classes_.data(), visitor.classes_.size());
384 }
385 }
386
387 extern "C" void art_quick_osr_stub(void** stack,
388 uint32_t stack_size_in_bytes,
389 const uint8_t* native_pc,
390 JValue* result,
391 const char* shorty,
392 Thread* self);
393
MaybeDoOnStackReplacement(Thread * thread,ArtMethod * method,uint32_t dex_pc,int32_t dex_pc_offset,JValue * result)394 bool Jit::MaybeDoOnStackReplacement(Thread* thread,
395 ArtMethod* method,
396 uint32_t dex_pc,
397 int32_t dex_pc_offset,
398 JValue* result) {
399 if (!kEnableOnStackReplacement) {
400 return false;
401 }
402
403 Jit* jit = Runtime::Current()->GetJit();
404 if (jit == nullptr) {
405 return false;
406 }
407
408 if (UNLIKELY(__builtin_frame_address(0) < thread->GetStackEnd())) {
409 // Don't attempt to do an OSR if we are close to the stack limit. Since
410 // the interpreter frames are still on stack, OSR has the potential
411 // to stack overflow even for a simple loop.
412 // b/27094810.
413 return false;
414 }
415
416 // Get the actual Java method if this method is from a proxy class. The compiler
417 // and the JIT code cache do not expect methods from proxy classes.
418 method = method->GetInterfaceMethodIfProxy(sizeof(void*));
419
420 // Cheap check if the method has been compiled already. That's an indicator that we should
421 // osr into it.
422 if (!jit->GetCodeCache()->ContainsPc(method->GetEntryPointFromQuickCompiledCode())) {
423 return false;
424 }
425
426 // Fetch some data before looking up for an OSR method. We don't want thread
427 // suspension once we hold an OSR method, as the JIT code cache could delete the OSR
428 // method while we are being suspended.
429 const size_t number_of_vregs = method->GetCodeItem()->registers_size_;
430 const char* shorty = method->GetShorty();
431 std::string method_name(VLOG_IS_ON(jit) ? PrettyMethod(method) : "");
432 void** memory = nullptr;
433 size_t frame_size = 0;
434 ShadowFrame* shadow_frame = nullptr;
435 const uint8_t* native_pc = nullptr;
436
437 {
438 ScopedAssertNoThreadSuspension sts(thread, "Holding OSR method");
439 const OatQuickMethodHeader* osr_method = jit->GetCodeCache()->LookupOsrMethodHeader(method);
440 if (osr_method == nullptr) {
441 // No osr method yet, just return to the interpreter.
442 return false;
443 }
444
445 CodeInfo code_info = osr_method->GetOptimizedCodeInfo();
446 CodeInfoEncoding encoding = code_info.ExtractEncoding();
447
448 // Find stack map starting at the target dex_pc.
449 StackMap stack_map = code_info.GetOsrStackMapForDexPc(dex_pc + dex_pc_offset, encoding);
450 if (!stack_map.IsValid()) {
451 // There is no OSR stack map for this dex pc offset. Just return to the interpreter in the
452 // hope that the next branch has one.
453 return false;
454 }
455
456 // Before allowing the jump, make sure the debugger is not active to avoid jumping from
457 // interpreter to OSR while e.g. single stepping. Note that we could selectively disable
458 // OSR when single stepping, but that's currently hard to know at this point.
459 if (Dbg::IsDebuggerActive()) {
460 return false;
461 }
462
463 // We found a stack map, now fill the frame with dex register values from the interpreter's
464 // shadow frame.
465 DexRegisterMap vreg_map =
466 code_info.GetDexRegisterMapOf(stack_map, encoding, number_of_vregs);
467
468 frame_size = osr_method->GetFrameSizeInBytes();
469
470 // Allocate memory to put shadow frame values. The osr stub will copy that memory to
471 // stack.
472 // Note that we could pass the shadow frame to the stub, and let it copy the values there,
473 // but that is engineering complexity not worth the effort for something like OSR.
474 memory = reinterpret_cast<void**>(malloc(frame_size));
475 CHECK(memory != nullptr);
476 memset(memory, 0, frame_size);
477
478 // Art ABI: ArtMethod is at the bottom of the stack.
479 memory[0] = method;
480
481 shadow_frame = thread->PopShadowFrame();
482 if (!vreg_map.IsValid()) {
483 // If we don't have a dex register map, then there are no live dex registers at
484 // this dex pc.
485 } else {
486 for (uint16_t vreg = 0; vreg < number_of_vregs; ++vreg) {
487 DexRegisterLocation::Kind location =
488 vreg_map.GetLocationKind(vreg, number_of_vregs, code_info, encoding);
489 if (location == DexRegisterLocation::Kind::kNone) {
490 // Dex register is dead or uninitialized.
491 continue;
492 }
493
494 if (location == DexRegisterLocation::Kind::kConstant) {
495 // We skip constants because the compiled code knows how to handle them.
496 continue;
497 }
498
499 DCHECK_EQ(location, DexRegisterLocation::Kind::kInStack);
500
501 int32_t vreg_value = shadow_frame->GetVReg(vreg);
502 int32_t slot_offset = vreg_map.GetStackOffsetInBytes(vreg,
503 number_of_vregs,
504 code_info,
505 encoding);
506 DCHECK_LT(slot_offset, static_cast<int32_t>(frame_size));
507 DCHECK_GT(slot_offset, 0);
508 (reinterpret_cast<int32_t*>(memory))[slot_offset / sizeof(int32_t)] = vreg_value;
509 }
510 }
511
512 native_pc = stack_map.GetNativePcOffset(encoding.stack_map_encoding) +
513 osr_method->GetEntryPoint();
514 VLOG(jit) << "Jumping to "
515 << method_name
516 << "@"
517 << std::hex << reinterpret_cast<uintptr_t>(native_pc);
518 }
519
520 {
521 ManagedStack fragment;
522 thread->PushManagedStackFragment(&fragment);
523 (*art_quick_osr_stub)(memory,
524 frame_size,
525 native_pc,
526 result,
527 shorty,
528 thread);
529
530 if (UNLIKELY(thread->GetException() == Thread::GetDeoptimizationException())) {
531 thread->DeoptimizeWithDeoptimizationException(result);
532 }
533 thread->PopManagedStackFragment(fragment);
534 }
535 free(memory);
536 thread->PushShadowFrame(shadow_frame);
537 VLOG(jit) << "Done running OSR code for " << method_name;
538 return true;
539 }
540
AddMemoryUsage(ArtMethod * method,size_t bytes)541 void Jit::AddMemoryUsage(ArtMethod* method, size_t bytes) {
542 if (bytes > 4 * MB) {
543 LOG(INFO) << "Compiler allocated "
544 << PrettySize(bytes)
545 << " to compile "
546 << PrettyMethod(method);
547 }
548 MutexLock mu(Thread::Current(), lock_);
549 memory_use_.AddValue(bytes);
550 }
551
552 class JitCompileTask FINAL : public Task {
553 public:
554 enum TaskKind {
555 kAllocateProfile,
556 kCompile,
557 kCompileOsr
558 };
559
JitCompileTask(ArtMethod * method,TaskKind kind)560 JitCompileTask(ArtMethod* method, TaskKind kind) : method_(method), kind_(kind) {
561 ScopedObjectAccess soa(Thread::Current());
562 // Add a global ref to the class to prevent class unloading until compilation is done.
563 klass_ = soa.Vm()->AddGlobalRef(soa.Self(), method_->GetDeclaringClass());
564 CHECK(klass_ != nullptr);
565 }
566
~JitCompileTask()567 ~JitCompileTask() {
568 ScopedObjectAccess soa(Thread::Current());
569 soa.Vm()->DeleteGlobalRef(soa.Self(), klass_);
570 }
571
Run(Thread * self)572 void Run(Thread* self) OVERRIDE {
573 ScopedObjectAccess soa(self);
574 if (kind_ == kCompile) {
575 Runtime::Current()->GetJit()->CompileMethod(method_, self, /* osr */ false);
576 } else if (kind_ == kCompileOsr) {
577 Runtime::Current()->GetJit()->CompileMethod(method_, self, /* osr */ true);
578 } else {
579 DCHECK(kind_ == kAllocateProfile);
580 if (ProfilingInfo::Create(self, method_, /* retry_allocation */ true)) {
581 VLOG(jit) << "Start profiling " << PrettyMethod(method_);
582 }
583 }
584 ProfileSaver::NotifyJitActivity();
585 }
586
Finalize()587 void Finalize() OVERRIDE {
588 delete this;
589 }
590
591 private:
592 ArtMethod* const method_;
593 const TaskKind kind_;
594 jobject klass_;
595
596 DISALLOW_IMPLICIT_CONSTRUCTORS(JitCompileTask);
597 };
598
AddSamples(Thread * self,ArtMethod * method,uint16_t count,bool with_backedges)599 void Jit::AddSamples(Thread* self, ArtMethod* method, uint16_t count, bool with_backedges) {
600 if (thread_pool_ == nullptr) {
601 // Should only see this when shutting down.
602 DCHECK(Runtime::Current()->IsShuttingDown(self));
603 return;
604 }
605
606 if (method->IsClassInitializer() || method->IsNative() || !method->IsCompilable()) {
607 // We do not want to compile such methods.
608 return;
609 }
610 DCHECK(thread_pool_ != nullptr);
611 DCHECK_GT(warm_method_threshold_, 0);
612 DCHECK_GT(hot_method_threshold_, warm_method_threshold_);
613 DCHECK_GT(osr_method_threshold_, hot_method_threshold_);
614 DCHECK_GE(priority_thread_weight_, 1);
615 DCHECK_LE(priority_thread_weight_, hot_method_threshold_);
616
617 int32_t starting_count = method->GetCounter();
618 if (Jit::ShouldUsePriorityThreadWeight()) {
619 count *= priority_thread_weight_;
620 }
621 int32_t new_count = starting_count + count; // int32 here to avoid wrap-around;
622 if (starting_count < warm_method_threshold_) {
623 if ((new_count >= warm_method_threshold_) &&
624 (method->GetProfilingInfo(sizeof(void*)) == nullptr)) {
625 bool success = ProfilingInfo::Create(self, method, /* retry_allocation */ false);
626 if (success) {
627 VLOG(jit) << "Start profiling " << PrettyMethod(method);
628 }
629
630 if (thread_pool_ == nullptr) {
631 // Calling ProfilingInfo::Create might put us in a suspended state, which could
632 // lead to the thread pool being deleted when we are shutting down.
633 DCHECK(Runtime::Current()->IsShuttingDown(self));
634 return;
635 }
636
637 if (!success) {
638 // We failed allocating. Instead of doing the collection on the Java thread, we push
639 // an allocation to a compiler thread, that will do the collection.
640 thread_pool_->AddTask(self, new JitCompileTask(method, JitCompileTask::kAllocateProfile));
641 }
642 }
643 // Avoid jumping more than one state at a time.
644 new_count = std::min(new_count, hot_method_threshold_ - 1);
645 } else if (use_jit_compilation_) {
646 if (starting_count < hot_method_threshold_) {
647 if ((new_count >= hot_method_threshold_) &&
648 !code_cache_->ContainsPc(method->GetEntryPointFromQuickCompiledCode())) {
649 DCHECK(thread_pool_ != nullptr);
650 thread_pool_->AddTask(self, new JitCompileTask(method, JitCompileTask::kCompile));
651 }
652 // Avoid jumping more than one state at a time.
653 new_count = std::min(new_count, osr_method_threshold_ - 1);
654 } else if (starting_count < osr_method_threshold_) {
655 if (!with_backedges) {
656 // If the samples don't contain any back edge, we don't increment the hotness.
657 return;
658 }
659 if ((new_count >= osr_method_threshold_) && !code_cache_->IsOsrCompiled(method)) {
660 DCHECK(thread_pool_ != nullptr);
661 thread_pool_->AddTask(self, new JitCompileTask(method, JitCompileTask::kCompileOsr));
662 }
663 }
664 }
665 // Update hotness counter
666 method->SetCounter(new_count);
667 }
668
MethodEntered(Thread * thread,ArtMethod * method)669 void Jit::MethodEntered(Thread* thread, ArtMethod* method) {
670 Runtime* runtime = Runtime::Current();
671 if (UNLIKELY(runtime->UseJitCompilation() && runtime->GetJit()->JitAtFirstUse())) {
672 // The compiler requires a ProfilingInfo object.
673 ProfilingInfo::Create(thread, method, /* retry_allocation */ true);
674 JitCompileTask compile_task(method, JitCompileTask::kCompile);
675 compile_task.Run(thread);
676 return;
677 }
678
679 ProfilingInfo* profiling_info = method->GetProfilingInfo(sizeof(void*));
680 // Update the entrypoint if the ProfilingInfo has one. The interpreter will call it
681 // instead of interpreting the method.
682 if ((profiling_info != nullptr) && (profiling_info->GetSavedEntryPoint() != nullptr)) {
683 Runtime::Current()->GetInstrumentation()->UpdateMethodsCode(
684 method, profiling_info->GetSavedEntryPoint());
685 } else {
686 AddSamples(thread, method, 1, /* with_backedges */false);
687 }
688 }
689
InvokeVirtualOrInterface(Thread * thread,mirror::Object * this_object,ArtMethod * caller,uint32_t dex_pc,ArtMethod * callee ATTRIBUTE_UNUSED)690 void Jit::InvokeVirtualOrInterface(Thread* thread,
691 mirror::Object* this_object,
692 ArtMethod* caller,
693 uint32_t dex_pc,
694 ArtMethod* callee ATTRIBUTE_UNUSED) {
695 ScopedAssertNoThreadSuspension ants(thread, __FUNCTION__);
696 DCHECK(this_object != nullptr);
697 ProfilingInfo* info = caller->GetProfilingInfo(sizeof(void*));
698 if (info != nullptr) {
699 info->AddInvokeInfo(dex_pc, this_object->GetClass());
700 }
701 }
702
WaitForCompilationToFinish(Thread * self)703 void Jit::WaitForCompilationToFinish(Thread* self) {
704 if (thread_pool_ != nullptr) {
705 thread_pool_->Wait(self, false, false);
706 }
707 }
708
709 } // namespace jit
710 } // namespace art
711