1 /*
2  * Copyright (C) 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 "code_generator.h"
18 
19 #ifdef ART_ENABLE_CODEGEN_arm
20 #include "code_generator_arm_vixl.h"
21 #endif
22 
23 #ifdef ART_ENABLE_CODEGEN_arm64
24 #include "code_generator_arm64.h"
25 #endif
26 
27 #ifdef ART_ENABLE_CODEGEN_x86
28 #include "code_generator_x86.h"
29 #endif
30 
31 #ifdef ART_ENABLE_CODEGEN_x86_64
32 #include "code_generator_x86_64.h"
33 #endif
34 
35 #include "base/bit_utils.h"
36 #include "base/bit_utils_iterator.h"
37 #include "base/casts.h"
38 #include "base/leb128.h"
39 #include "class_linker.h"
40 #include "compiled_method.h"
41 #include "dex/bytecode_utils.h"
42 #include "dex/code_item_accessors-inl.h"
43 #include "dex/verified_method.h"
44 #include "graph_visualizer.h"
45 #include "image.h"
46 #include "gc/space/image_space.h"
47 #include "intern_table.h"
48 #include "intrinsics.h"
49 #include "mirror/array-inl.h"
50 #include "mirror/object_array-inl.h"
51 #include "mirror/object_reference.h"
52 #include "mirror/reference.h"
53 #include "mirror/string.h"
54 #include "parallel_move_resolver.h"
55 #include "scoped_thread_state_change-inl.h"
56 #include "ssa_liveness_analysis.h"
57 #include "stack_map.h"
58 #include "stack_map_stream.h"
59 #include "string_builder_append.h"
60 #include "thread-current-inl.h"
61 #include "utils/assembler.h"
62 
63 namespace art {
64 
65 // Return whether a location is consistent with a type.
CheckType(DataType::Type type,Location location)66 static bool CheckType(DataType::Type type, Location location) {
67   if (location.IsFpuRegister()
68       || (location.IsUnallocated() && (location.GetPolicy() == Location::kRequiresFpuRegister))) {
69     return (type == DataType::Type::kFloat32) || (type == DataType::Type::kFloat64);
70   } else if (location.IsRegister() ||
71              (location.IsUnallocated() && (location.GetPolicy() == Location::kRequiresRegister))) {
72     return DataType::IsIntegralType(type) || (type == DataType::Type::kReference);
73   } else if (location.IsRegisterPair()) {
74     return type == DataType::Type::kInt64;
75   } else if (location.IsFpuRegisterPair()) {
76     return type == DataType::Type::kFloat64;
77   } else if (location.IsStackSlot()) {
78     return (DataType::IsIntegralType(type) && type != DataType::Type::kInt64)
79            || (type == DataType::Type::kFloat32)
80            || (type == DataType::Type::kReference);
81   } else if (location.IsDoubleStackSlot()) {
82     return (type == DataType::Type::kInt64) || (type == DataType::Type::kFloat64);
83   } else if (location.IsConstant()) {
84     if (location.GetConstant()->IsIntConstant()) {
85       return DataType::IsIntegralType(type) && (type != DataType::Type::kInt64);
86     } else if (location.GetConstant()->IsNullConstant()) {
87       return type == DataType::Type::kReference;
88     } else if (location.GetConstant()->IsLongConstant()) {
89       return type == DataType::Type::kInt64;
90     } else if (location.GetConstant()->IsFloatConstant()) {
91       return type == DataType::Type::kFloat32;
92     } else {
93       return location.GetConstant()->IsDoubleConstant()
94           && (type == DataType::Type::kFloat64);
95     }
96   } else {
97     return location.IsInvalid() || (location.GetPolicy() == Location::kAny);
98   }
99 }
100 
101 // Check that a location summary is consistent with an instruction.
CheckTypeConsistency(HInstruction * instruction)102 static bool CheckTypeConsistency(HInstruction* instruction) {
103   LocationSummary* locations = instruction->GetLocations();
104   if (locations == nullptr) {
105     return true;
106   }
107 
108   if (locations->Out().IsUnallocated()
109       && (locations->Out().GetPolicy() == Location::kSameAsFirstInput)) {
110     DCHECK(CheckType(instruction->GetType(), locations->InAt(0)))
111         << instruction->GetType()
112         << " " << locations->InAt(0);
113   } else {
114     DCHECK(CheckType(instruction->GetType(), locations->Out()))
115         << instruction->GetType()
116         << " " << locations->Out();
117   }
118 
119   HConstInputsRef inputs = instruction->GetInputs();
120   for (size_t i = 0; i < inputs.size(); ++i) {
121     DCHECK(CheckType(inputs[i]->GetType(), locations->InAt(i)))
122       << inputs[i]->GetType() << " " << locations->InAt(i);
123   }
124 
125   HEnvironment* environment = instruction->GetEnvironment();
126   for (size_t i = 0; i < instruction->EnvironmentSize(); ++i) {
127     if (environment->GetInstructionAt(i) != nullptr) {
128       DataType::Type type = environment->GetInstructionAt(i)->GetType();
129       DCHECK(CheckType(type, environment->GetLocationAt(i)))
130         << type << " " << environment->GetLocationAt(i);
131     } else {
132       DCHECK(environment->GetLocationAt(i).IsInvalid())
133         << environment->GetLocationAt(i);
134     }
135   }
136   return true;
137 }
138 
139 class CodeGenerator::CodeGenerationData : public DeletableArenaObject<kArenaAllocCodeGenerator> {
140  public:
Create(ArenaStack * arena_stack,InstructionSet instruction_set)141   static std::unique_ptr<CodeGenerationData> Create(ArenaStack* arena_stack,
142                                                     InstructionSet instruction_set) {
143     ScopedArenaAllocator allocator(arena_stack);
144     void* memory = allocator.Alloc<CodeGenerationData>(kArenaAllocCodeGenerator);
145     return std::unique_ptr<CodeGenerationData>(
146         ::new (memory) CodeGenerationData(std::move(allocator), instruction_set));
147   }
148 
GetScopedAllocator()149   ScopedArenaAllocator* GetScopedAllocator() {
150     return &allocator_;
151   }
152 
AddSlowPath(SlowPathCode * slow_path)153   void AddSlowPath(SlowPathCode* slow_path) {
154     slow_paths_.emplace_back(std::unique_ptr<SlowPathCode>(slow_path));
155   }
156 
GetSlowPaths() const157   ArrayRef<const std::unique_ptr<SlowPathCode>> GetSlowPaths() const {
158     return ArrayRef<const std::unique_ptr<SlowPathCode>>(slow_paths_);
159   }
160 
GetStackMapStream()161   StackMapStream* GetStackMapStream() { return &stack_map_stream_; }
162 
ReserveJitStringRoot(StringReference string_reference,Handle<mirror::String> string)163   void ReserveJitStringRoot(StringReference string_reference, Handle<mirror::String> string) {
164     jit_string_roots_.Overwrite(string_reference,
165                                 reinterpret_cast64<uint64_t>(string.GetReference()));
166   }
167 
GetJitStringRootIndex(StringReference string_reference) const168   uint64_t GetJitStringRootIndex(StringReference string_reference) const {
169     return jit_string_roots_.Get(string_reference);
170   }
171 
GetNumberOfJitStringRoots() const172   size_t GetNumberOfJitStringRoots() const {
173     return jit_string_roots_.size();
174   }
175 
ReserveJitClassRoot(TypeReference type_reference,Handle<mirror::Class> klass)176   void ReserveJitClassRoot(TypeReference type_reference, Handle<mirror::Class> klass) {
177     jit_class_roots_.Overwrite(type_reference, reinterpret_cast64<uint64_t>(klass.GetReference()));
178   }
179 
GetJitClassRootIndex(TypeReference type_reference) const180   uint64_t GetJitClassRootIndex(TypeReference type_reference) const {
181     return jit_class_roots_.Get(type_reference);
182   }
183 
GetNumberOfJitClassRoots() const184   size_t GetNumberOfJitClassRoots() const {
185     return jit_class_roots_.size();
186   }
187 
GetNumberOfJitRoots() const188   size_t GetNumberOfJitRoots() const {
189     return GetNumberOfJitStringRoots() + GetNumberOfJitClassRoots();
190   }
191 
192   void EmitJitRoots(/*out*/std::vector<Handle<mirror::Object>>* roots)
193       REQUIRES_SHARED(Locks::mutator_lock_);
194 
195  private:
CodeGenerationData(ScopedArenaAllocator && allocator,InstructionSet instruction_set)196   CodeGenerationData(ScopedArenaAllocator&& allocator, InstructionSet instruction_set)
197       : allocator_(std::move(allocator)),
198         stack_map_stream_(&allocator_, instruction_set),
199         slow_paths_(allocator_.Adapter(kArenaAllocCodeGenerator)),
200         jit_string_roots_(StringReferenceValueComparator(),
201                           allocator_.Adapter(kArenaAllocCodeGenerator)),
202         jit_class_roots_(TypeReferenceValueComparator(),
203                          allocator_.Adapter(kArenaAllocCodeGenerator)) {
204     slow_paths_.reserve(kDefaultSlowPathsCapacity);
205   }
206 
207   static constexpr size_t kDefaultSlowPathsCapacity = 8;
208 
209   ScopedArenaAllocator allocator_;
210   StackMapStream stack_map_stream_;
211   ScopedArenaVector<std::unique_ptr<SlowPathCode>> slow_paths_;
212 
213   // Maps a StringReference (dex_file, string_index) to the index in the literal table.
214   // Entries are intially added with a pointer in the handle zone, and `EmitJitRoots`
215   // will compute all the indices.
216   ScopedArenaSafeMap<StringReference, uint64_t, StringReferenceValueComparator> jit_string_roots_;
217 
218   // Maps a ClassReference (dex_file, type_index) to the index in the literal table.
219   // Entries are intially added with a pointer in the handle zone, and `EmitJitRoots`
220   // will compute all the indices.
221   ScopedArenaSafeMap<TypeReference, uint64_t, TypeReferenceValueComparator> jit_class_roots_;
222 };
223 
EmitJitRoots(std::vector<Handle<mirror::Object>> * roots)224 void CodeGenerator::CodeGenerationData::EmitJitRoots(
225     /*out*/std::vector<Handle<mirror::Object>>* roots) {
226   DCHECK(roots->empty());
227   roots->reserve(GetNumberOfJitRoots());
228   ClassLinker* class_linker = Runtime::Current()->GetClassLinker();
229   size_t index = 0;
230   for (auto& entry : jit_string_roots_) {
231     // Update the `roots` with the string, and replace the address temporarily
232     // stored to the index in the table.
233     uint64_t address = entry.second;
234     roots->emplace_back(reinterpret_cast<StackReference<mirror::Object>*>(address));
235     DCHECK(roots->back() != nullptr);
236     DCHECK(roots->back()->IsString());
237     entry.second = index;
238     // Ensure the string is strongly interned. This is a requirement on how the JIT
239     // handles strings. b/32995596
240     class_linker->GetInternTable()->InternStrong(roots->back()->AsString());
241     ++index;
242   }
243   for (auto& entry : jit_class_roots_) {
244     // Update the `roots` with the class, and replace the address temporarily
245     // stored to the index in the table.
246     uint64_t address = entry.second;
247     roots->emplace_back(reinterpret_cast<StackReference<mirror::Object>*>(address));
248     DCHECK(roots->back() != nullptr);
249     DCHECK(roots->back()->IsClass());
250     entry.second = index;
251     ++index;
252   }
253 }
254 
GetScopedAllocator()255 ScopedArenaAllocator* CodeGenerator::GetScopedAllocator() {
256   DCHECK(code_generation_data_ != nullptr);
257   return code_generation_data_->GetScopedAllocator();
258 }
259 
GetStackMapStream()260 StackMapStream* CodeGenerator::GetStackMapStream() {
261   DCHECK(code_generation_data_ != nullptr);
262   return code_generation_data_->GetStackMapStream();
263 }
264 
ReserveJitStringRoot(StringReference string_reference,Handle<mirror::String> string)265 void CodeGenerator::ReserveJitStringRoot(StringReference string_reference,
266                                          Handle<mirror::String> string) {
267   DCHECK(code_generation_data_ != nullptr);
268   code_generation_data_->ReserveJitStringRoot(string_reference, string);
269 }
270 
GetJitStringRootIndex(StringReference string_reference)271 uint64_t CodeGenerator::GetJitStringRootIndex(StringReference string_reference) {
272   DCHECK(code_generation_data_ != nullptr);
273   return code_generation_data_->GetJitStringRootIndex(string_reference);
274 }
275 
ReserveJitClassRoot(TypeReference type_reference,Handle<mirror::Class> klass)276 void CodeGenerator::ReserveJitClassRoot(TypeReference type_reference, Handle<mirror::Class> klass) {
277   DCHECK(code_generation_data_ != nullptr);
278   code_generation_data_->ReserveJitClassRoot(type_reference, klass);
279 }
280 
GetJitClassRootIndex(TypeReference type_reference)281 uint64_t CodeGenerator::GetJitClassRootIndex(TypeReference type_reference) {
282   DCHECK(code_generation_data_ != nullptr);
283   return code_generation_data_->GetJitClassRootIndex(type_reference);
284 }
285 
EmitJitRootPatches(uint8_t * code ATTRIBUTE_UNUSED,const uint8_t * roots_data ATTRIBUTE_UNUSED)286 void CodeGenerator::EmitJitRootPatches(uint8_t* code ATTRIBUTE_UNUSED,
287                                        const uint8_t* roots_data ATTRIBUTE_UNUSED) {
288   DCHECK(code_generation_data_ != nullptr);
289   DCHECK_EQ(code_generation_data_->GetNumberOfJitStringRoots(), 0u);
290   DCHECK_EQ(code_generation_data_->GetNumberOfJitClassRoots(), 0u);
291 }
292 
GetArrayLengthOffset(HArrayLength * array_length)293 uint32_t CodeGenerator::GetArrayLengthOffset(HArrayLength* array_length) {
294   return array_length->IsStringLength()
295       ? mirror::String::CountOffset().Uint32Value()
296       : mirror::Array::LengthOffset().Uint32Value();
297 }
298 
GetArrayDataOffset(HArrayGet * array_get)299 uint32_t CodeGenerator::GetArrayDataOffset(HArrayGet* array_get) {
300   DCHECK(array_get->GetType() == DataType::Type::kUint16 || !array_get->IsStringCharAt());
301   return array_get->IsStringCharAt()
302       ? mirror::String::ValueOffset().Uint32Value()
303       : mirror::Array::DataOffset(DataType::Size(array_get->GetType())).Uint32Value();
304 }
305 
GoesToNextBlock(HBasicBlock * current,HBasicBlock * next) const306 bool CodeGenerator::GoesToNextBlock(HBasicBlock* current, HBasicBlock* next) const {
307   DCHECK_EQ((*block_order_)[current_block_index_], current);
308   return GetNextBlockToEmit() == FirstNonEmptyBlock(next);
309 }
310 
GetNextBlockToEmit() const311 HBasicBlock* CodeGenerator::GetNextBlockToEmit() const {
312   for (size_t i = current_block_index_ + 1; i < block_order_->size(); ++i) {
313     HBasicBlock* block = (*block_order_)[i];
314     if (!block->IsSingleJump()) {
315       return block;
316     }
317   }
318   return nullptr;
319 }
320 
FirstNonEmptyBlock(HBasicBlock * block) const321 HBasicBlock* CodeGenerator::FirstNonEmptyBlock(HBasicBlock* block) const {
322   while (block->IsSingleJump()) {
323     block = block->GetSuccessors()[0];
324   }
325   return block;
326 }
327 
328 class DisassemblyScope {
329  public:
DisassemblyScope(HInstruction * instruction,const CodeGenerator & codegen)330   DisassemblyScope(HInstruction* instruction, const CodeGenerator& codegen)
331       : codegen_(codegen), instruction_(instruction), start_offset_(static_cast<size_t>(-1)) {
332     if (codegen_.GetDisassemblyInformation() != nullptr) {
333       start_offset_ = codegen_.GetAssembler().CodeSize();
334     }
335   }
336 
~DisassemblyScope()337   ~DisassemblyScope() {
338     // We avoid building this data when we know it will not be used.
339     if (codegen_.GetDisassemblyInformation() != nullptr) {
340       codegen_.GetDisassemblyInformation()->AddInstructionInterval(
341           instruction_, start_offset_, codegen_.GetAssembler().CodeSize());
342     }
343   }
344 
345  private:
346   const CodeGenerator& codegen_;
347   HInstruction* instruction_;
348   size_t start_offset_;
349 };
350 
351 
GenerateSlowPaths()352 void CodeGenerator::GenerateSlowPaths() {
353   DCHECK(code_generation_data_ != nullptr);
354   size_t code_start = 0;
355   for (const std::unique_ptr<SlowPathCode>& slow_path_ptr : code_generation_data_->GetSlowPaths()) {
356     SlowPathCode* slow_path = slow_path_ptr.get();
357     current_slow_path_ = slow_path;
358     if (disasm_info_ != nullptr) {
359       code_start = GetAssembler()->CodeSize();
360     }
361     // Record the dex pc at start of slow path (required for java line number mapping).
362     MaybeRecordNativeDebugInfo(slow_path->GetInstruction(), slow_path->GetDexPc(), slow_path);
363     slow_path->EmitNativeCode(this);
364     if (disasm_info_ != nullptr) {
365       disasm_info_->AddSlowPathInterval(slow_path, code_start, GetAssembler()->CodeSize());
366     }
367   }
368   current_slow_path_ = nullptr;
369 }
370 
InitializeCodeGenerationData()371 void CodeGenerator::InitializeCodeGenerationData() {
372   DCHECK(code_generation_data_ == nullptr);
373   code_generation_data_ = CodeGenerationData::Create(graph_->GetArenaStack(), GetInstructionSet());
374 }
375 
Compile(CodeAllocator * allocator)376 void CodeGenerator::Compile(CodeAllocator* allocator) {
377   InitializeCodeGenerationData();
378 
379   // The register allocator already called `InitializeCodeGeneration`,
380   // where the frame size has been computed.
381   DCHECK(block_order_ != nullptr);
382   Initialize();
383 
384   HGraphVisitor* instruction_visitor = GetInstructionVisitor();
385   DCHECK_EQ(current_block_index_, 0u);
386 
387   GetStackMapStream()->BeginMethod(HasEmptyFrame() ? 0 : frame_size_,
388                                    core_spill_mask_,
389                                    fpu_spill_mask_,
390                                    GetGraph()->GetNumberOfVRegs(),
391                                    GetGraph()->IsCompilingBaseline());
392 
393   size_t frame_start = GetAssembler()->CodeSize();
394   GenerateFrameEntry();
395   DCHECK_EQ(GetAssembler()->cfi().GetCurrentCFAOffset(), static_cast<int>(frame_size_));
396   if (disasm_info_ != nullptr) {
397     disasm_info_->SetFrameEntryInterval(frame_start, GetAssembler()->CodeSize());
398   }
399 
400   for (size_t e = block_order_->size(); current_block_index_ < e; ++current_block_index_) {
401     HBasicBlock* block = (*block_order_)[current_block_index_];
402     // Don't generate code for an empty block. Its predecessors will branch to its successor
403     // directly. Also, the label of that block will not be emitted, so this helps catch
404     // errors where we reference that label.
405     if (block->IsSingleJump()) continue;
406     Bind(block);
407     // This ensures that we have correct native line mapping for all native instructions.
408     // It is necessary to make stepping over a statement work. Otherwise, any initial
409     // instructions (e.g. moves) would be assumed to be the start of next statement.
410     MaybeRecordNativeDebugInfo(/* instruction= */ nullptr, block->GetDexPc());
411     for (HInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
412       HInstruction* current = it.Current();
413       if (current->HasEnvironment()) {
414         // Create stackmap for HNativeDebugInfo or any instruction which calls native code.
415         // Note that we need correct mapping for the native PC of the call instruction,
416         // so the runtime's stackmap is not sufficient since it is at PC after the call.
417         MaybeRecordNativeDebugInfo(current, block->GetDexPc());
418       }
419       DisassemblyScope disassembly_scope(current, *this);
420       DCHECK(CheckTypeConsistency(current));
421       current->Accept(instruction_visitor);
422     }
423   }
424 
425   GenerateSlowPaths();
426 
427   // Emit catch stack maps at the end of the stack map stream as expected by the
428   // runtime exception handler.
429   if (graph_->HasTryCatch()) {
430     RecordCatchBlockInfo();
431   }
432 
433   // Finalize instructions in assember;
434   Finalize(allocator);
435 
436   GetStackMapStream()->EndMethod();
437 }
438 
Finalize(CodeAllocator * allocator)439 void CodeGenerator::Finalize(CodeAllocator* allocator) {
440   size_t code_size = GetAssembler()->CodeSize();
441   uint8_t* buffer = allocator->Allocate(code_size);
442 
443   MemoryRegion code(buffer, code_size);
444   GetAssembler()->FinalizeInstructions(code);
445 }
446 
EmitLinkerPatches(ArenaVector<linker::LinkerPatch> * linker_patches ATTRIBUTE_UNUSED)447 void CodeGenerator::EmitLinkerPatches(
448     ArenaVector<linker::LinkerPatch>* linker_patches ATTRIBUTE_UNUSED) {
449   // No linker patches by default.
450 }
451 
NeedsThunkCode(const linker::LinkerPatch & patch ATTRIBUTE_UNUSED) const452 bool CodeGenerator::NeedsThunkCode(const linker::LinkerPatch& patch ATTRIBUTE_UNUSED) const {
453   // Code generators that create patches requiring thunk compilation should override this function.
454   return false;
455 }
456 
EmitThunkCode(const linker::LinkerPatch & patch ATTRIBUTE_UNUSED,ArenaVector<uint8_t> * code ATTRIBUTE_UNUSED,std::string * debug_name ATTRIBUTE_UNUSED)457 void CodeGenerator::EmitThunkCode(const linker::LinkerPatch& patch ATTRIBUTE_UNUSED,
458                                   /*out*/ ArenaVector<uint8_t>* code ATTRIBUTE_UNUSED,
459                                   /*out*/ std::string* debug_name ATTRIBUTE_UNUSED) {
460   // Code generators that create patches requiring thunk compilation should override this function.
461   LOG(FATAL) << "Unexpected call to EmitThunkCode().";
462 }
463 
InitializeCodeGeneration(size_t number_of_spill_slots,size_t maximum_safepoint_spill_size,size_t number_of_out_slots,const ArenaVector<HBasicBlock * > & block_order)464 void CodeGenerator::InitializeCodeGeneration(size_t number_of_spill_slots,
465                                              size_t maximum_safepoint_spill_size,
466                                              size_t number_of_out_slots,
467                                              const ArenaVector<HBasicBlock*>& block_order) {
468   block_order_ = &block_order;
469   DCHECK(!block_order.empty());
470   DCHECK(block_order[0] == GetGraph()->GetEntryBlock());
471   ComputeSpillMask();
472   first_register_slot_in_slow_path_ = RoundUp(
473       (number_of_out_slots + number_of_spill_slots) * kVRegSize, GetPreferredSlotsAlignment());
474 
475   if (number_of_spill_slots == 0
476       && !HasAllocatedCalleeSaveRegisters()
477       && IsLeafMethod()
478       && !RequiresCurrentMethod()) {
479     DCHECK_EQ(maximum_safepoint_spill_size, 0u);
480     SetFrameSize(CallPushesPC() ? GetWordSize() : 0);
481   } else {
482     SetFrameSize(RoundUp(
483         first_register_slot_in_slow_path_
484         + maximum_safepoint_spill_size
485         + (GetGraph()->HasShouldDeoptimizeFlag() ? kShouldDeoptimizeFlagSize : 0)
486         + FrameEntrySpillSize(),
487         kStackAlignment));
488   }
489 }
490 
CreateCommonInvokeLocationSummary(HInvoke * invoke,InvokeDexCallingConventionVisitor * visitor)491 void CodeGenerator::CreateCommonInvokeLocationSummary(
492     HInvoke* invoke, InvokeDexCallingConventionVisitor* visitor) {
493   ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
494   LocationSummary* locations = new (allocator) LocationSummary(invoke,
495                                                                LocationSummary::kCallOnMainOnly);
496 
497   for (size_t i = 0; i < invoke->GetNumberOfArguments(); i++) {
498     HInstruction* input = invoke->InputAt(i);
499     locations->SetInAt(i, visitor->GetNextLocation(input->GetType()));
500   }
501 
502   locations->SetOut(visitor->GetReturnLocation(invoke->GetType()));
503 
504   if (invoke->IsInvokeStaticOrDirect()) {
505     HInvokeStaticOrDirect* call = invoke->AsInvokeStaticOrDirect();
506     switch (call->GetMethodLoadKind()) {
507       case HInvokeStaticOrDirect::MethodLoadKind::kRecursive:
508         locations->SetInAt(call->GetSpecialInputIndex(), visitor->GetMethodLocation());
509         break;
510       case HInvokeStaticOrDirect::MethodLoadKind::kRuntimeCall:
511         locations->AddTemp(visitor->GetMethodLocation());
512         locations->SetInAt(call->GetSpecialInputIndex(), Location::RequiresRegister());
513         break;
514       default:
515         locations->AddTemp(visitor->GetMethodLocation());
516         break;
517     }
518   } else if (!invoke->IsInvokePolymorphic()) {
519     locations->AddTemp(visitor->GetMethodLocation());
520   }
521 }
522 
GenerateInvokeStaticOrDirectRuntimeCall(HInvokeStaticOrDirect * invoke,Location temp,SlowPathCode * slow_path)523 void CodeGenerator::GenerateInvokeStaticOrDirectRuntimeCall(
524     HInvokeStaticOrDirect* invoke, Location temp, SlowPathCode* slow_path) {
525   MoveConstant(temp, invoke->GetDexMethodIndex());
526 
527   // The access check is unnecessary but we do not want to introduce
528   // extra entrypoints for the codegens that do not support some
529   // invoke type and fall back to the runtime call.
530 
531   // Initialize to anything to silent compiler warnings.
532   QuickEntrypointEnum entrypoint = kQuickInvokeStaticTrampolineWithAccessCheck;
533   switch (invoke->GetInvokeType()) {
534     case kStatic:
535       entrypoint = kQuickInvokeStaticTrampolineWithAccessCheck;
536       break;
537     case kDirect:
538       entrypoint = kQuickInvokeDirectTrampolineWithAccessCheck;
539       break;
540     case kSuper:
541       entrypoint = kQuickInvokeSuperTrampolineWithAccessCheck;
542       break;
543     case kVirtual:
544     case kInterface:
545     case kPolymorphic:
546     case kCustom:
547       LOG(FATAL) << "Unexpected invoke type: " << invoke->GetInvokeType();
548       UNREACHABLE();
549   }
550 
551   InvokeRuntime(entrypoint, invoke, invoke->GetDexPc(), slow_path);
552 }
GenerateInvokeUnresolvedRuntimeCall(HInvokeUnresolved * invoke)553 void CodeGenerator::GenerateInvokeUnresolvedRuntimeCall(HInvokeUnresolved* invoke) {
554   MoveConstant(invoke->GetLocations()->GetTemp(0), invoke->GetDexMethodIndex());
555 
556   // Initialize to anything to silent compiler warnings.
557   QuickEntrypointEnum entrypoint = kQuickInvokeStaticTrampolineWithAccessCheck;
558   switch (invoke->GetInvokeType()) {
559     case kStatic:
560       entrypoint = kQuickInvokeStaticTrampolineWithAccessCheck;
561       break;
562     case kDirect:
563       entrypoint = kQuickInvokeDirectTrampolineWithAccessCheck;
564       break;
565     case kVirtual:
566       entrypoint = kQuickInvokeVirtualTrampolineWithAccessCheck;
567       break;
568     case kSuper:
569       entrypoint = kQuickInvokeSuperTrampolineWithAccessCheck;
570       break;
571     case kInterface:
572       entrypoint = kQuickInvokeInterfaceTrampolineWithAccessCheck;
573       break;
574     case kPolymorphic:
575     case kCustom:
576       LOG(FATAL) << "Unexpected invoke type: " << invoke->GetInvokeType();
577       UNREACHABLE();
578   }
579   InvokeRuntime(entrypoint, invoke, invoke->GetDexPc(), nullptr);
580 }
581 
GenerateInvokePolymorphicCall(HInvokePolymorphic * invoke)582 void CodeGenerator::GenerateInvokePolymorphicCall(HInvokePolymorphic* invoke) {
583   // invoke-polymorphic does not use a temporary to convey any additional information (e.g. a
584   // method index) since it requires multiple info from the instruction (registers A, B, H). Not
585   // using the reservation has no effect on the registers used in the runtime call.
586   QuickEntrypointEnum entrypoint = kQuickInvokePolymorphic;
587   InvokeRuntime(entrypoint, invoke, invoke->GetDexPc(), nullptr);
588 }
589 
GenerateInvokeCustomCall(HInvokeCustom * invoke)590 void CodeGenerator::GenerateInvokeCustomCall(HInvokeCustom* invoke) {
591   MoveConstant(invoke->GetLocations()->GetTemp(0), invoke->GetCallSiteIndex());
592   QuickEntrypointEnum entrypoint = kQuickInvokeCustom;
593   InvokeRuntime(entrypoint, invoke, invoke->GetDexPc(), nullptr);
594 }
595 
CreateStringBuilderAppendLocations(HStringBuilderAppend * instruction,Location out)596 void CodeGenerator::CreateStringBuilderAppendLocations(HStringBuilderAppend* instruction,
597                                                        Location out) {
598   ArenaAllocator* allocator = GetGraph()->GetAllocator();
599   LocationSummary* locations =
600       new (allocator) LocationSummary(instruction, LocationSummary::kCallOnMainOnly);
601   locations->SetOut(out);
602   instruction->GetLocations()->SetInAt(instruction->FormatIndex(),
603                                        Location::ConstantLocation(instruction->GetFormat()));
604 
605   uint32_t format = static_cast<uint32_t>(instruction->GetFormat()->GetValue());
606   uint32_t f = format;
607   PointerSize pointer_size = InstructionSetPointerSize(GetInstructionSet());
608   size_t stack_offset = static_cast<size_t>(pointer_size);  // Start after the ArtMethod*.
609   for (size_t i = 0, num_args = instruction->GetNumberOfArguments(); i != num_args; ++i) {
610     StringBuilderAppend::Argument arg_type =
611         static_cast<StringBuilderAppend::Argument>(f & StringBuilderAppend::kArgMask);
612     switch (arg_type) {
613       case StringBuilderAppend::Argument::kStringBuilder:
614       case StringBuilderAppend::Argument::kString:
615       case StringBuilderAppend::Argument::kCharArray:
616         static_assert(sizeof(StackReference<mirror::Object>) == sizeof(uint32_t), "Size check.");
617         FALLTHROUGH_INTENDED;
618       case StringBuilderAppend::Argument::kBoolean:
619       case StringBuilderAppend::Argument::kChar:
620       case StringBuilderAppend::Argument::kInt:
621       case StringBuilderAppend::Argument::kFloat:
622         locations->SetInAt(i, Location::StackSlot(stack_offset));
623         break;
624       case StringBuilderAppend::Argument::kLong:
625       case StringBuilderAppend::Argument::kDouble:
626         stack_offset = RoundUp(stack_offset, sizeof(uint64_t));
627         locations->SetInAt(i, Location::DoubleStackSlot(stack_offset));
628         // Skip the low word, let the common code skip the high word.
629         stack_offset += sizeof(uint32_t);
630         break;
631       default:
632         LOG(FATAL) << "Unexpected arg format: 0x" << std::hex
633             << (f & StringBuilderAppend::kArgMask) << " full format: 0x" << format;
634         UNREACHABLE();
635     }
636     f >>= StringBuilderAppend::kBitsPerArg;
637     stack_offset += sizeof(uint32_t);
638   }
639   DCHECK_EQ(f, 0u);
640 
641   size_t param_size = stack_offset - static_cast<size_t>(pointer_size);
642   DCHECK_ALIGNED(param_size, kVRegSize);
643   size_t num_vregs = param_size / kVRegSize;
644   graph_->UpdateMaximumNumberOfOutVRegs(num_vregs);
645 }
646 
CreateUnresolvedFieldLocationSummary(HInstruction * field_access,DataType::Type field_type,const FieldAccessCallingConvention & calling_convention)647 void CodeGenerator::CreateUnresolvedFieldLocationSummary(
648     HInstruction* field_access,
649     DataType::Type field_type,
650     const FieldAccessCallingConvention& calling_convention) {
651   bool is_instance = field_access->IsUnresolvedInstanceFieldGet()
652       || field_access->IsUnresolvedInstanceFieldSet();
653   bool is_get = field_access->IsUnresolvedInstanceFieldGet()
654       || field_access->IsUnresolvedStaticFieldGet();
655 
656   ArenaAllocator* allocator = field_access->GetBlock()->GetGraph()->GetAllocator();
657   LocationSummary* locations =
658       new (allocator) LocationSummary(field_access, LocationSummary::kCallOnMainOnly);
659 
660   locations->AddTemp(calling_convention.GetFieldIndexLocation());
661 
662   if (is_instance) {
663     // Add the `this` object for instance field accesses.
664     locations->SetInAt(0, calling_convention.GetObjectLocation());
665   }
666 
667   // Note that pSetXXStatic/pGetXXStatic always takes/returns an int or int64
668   // regardless of the the type. Because of that we forced to special case
669   // the access to floating point values.
670   if (is_get) {
671     if (DataType::IsFloatingPointType(field_type)) {
672       // The return value will be stored in regular registers while register
673       // allocator expects it in a floating point register.
674       // Note We don't need to request additional temps because the return
675       // register(s) are already blocked due the call and they may overlap with
676       // the input or field index.
677       // The transfer between the two will be done at codegen level.
678       locations->SetOut(calling_convention.GetFpuLocation(field_type));
679     } else {
680       locations->SetOut(calling_convention.GetReturnLocation(field_type));
681     }
682   } else {
683      size_t set_index = is_instance ? 1 : 0;
684      if (DataType::IsFloatingPointType(field_type)) {
685       // The set value comes from a float location while the calling convention
686       // expects it in a regular register location. Allocate a temp for it and
687       // make the transfer at codegen.
688       AddLocationAsTemp(calling_convention.GetSetValueLocation(field_type, is_instance), locations);
689       locations->SetInAt(set_index, calling_convention.GetFpuLocation(field_type));
690     } else {
691       locations->SetInAt(set_index,
692           calling_convention.GetSetValueLocation(field_type, is_instance));
693     }
694   }
695 }
696 
GenerateUnresolvedFieldAccess(HInstruction * field_access,DataType::Type field_type,uint32_t field_index,uint32_t dex_pc,const FieldAccessCallingConvention & calling_convention)697 void CodeGenerator::GenerateUnresolvedFieldAccess(
698     HInstruction* field_access,
699     DataType::Type field_type,
700     uint32_t field_index,
701     uint32_t dex_pc,
702     const FieldAccessCallingConvention& calling_convention) {
703   LocationSummary* locations = field_access->GetLocations();
704 
705   MoveConstant(locations->GetTemp(0), field_index);
706 
707   bool is_instance = field_access->IsUnresolvedInstanceFieldGet()
708       || field_access->IsUnresolvedInstanceFieldSet();
709   bool is_get = field_access->IsUnresolvedInstanceFieldGet()
710       || field_access->IsUnresolvedStaticFieldGet();
711 
712   if (!is_get && DataType::IsFloatingPointType(field_type)) {
713     // Copy the float value to be set into the calling convention register.
714     // Note that using directly the temp location is problematic as we don't
715     // support temp register pairs. To avoid boilerplate conversion code, use
716     // the location from the calling convention.
717     MoveLocation(calling_convention.GetSetValueLocation(field_type, is_instance),
718                  locations->InAt(is_instance ? 1 : 0),
719                  (DataType::Is64BitType(field_type) ? DataType::Type::kInt64
720                                                     : DataType::Type::kInt32));
721   }
722 
723   QuickEntrypointEnum entrypoint = kQuickSet8Static;  // Initialize to anything to avoid warnings.
724   switch (field_type) {
725     case DataType::Type::kBool:
726       entrypoint = is_instance
727           ? (is_get ? kQuickGetBooleanInstance : kQuickSet8Instance)
728           : (is_get ? kQuickGetBooleanStatic : kQuickSet8Static);
729       break;
730     case DataType::Type::kInt8:
731       entrypoint = is_instance
732           ? (is_get ? kQuickGetByteInstance : kQuickSet8Instance)
733           : (is_get ? kQuickGetByteStatic : kQuickSet8Static);
734       break;
735     case DataType::Type::kInt16:
736       entrypoint = is_instance
737           ? (is_get ? kQuickGetShortInstance : kQuickSet16Instance)
738           : (is_get ? kQuickGetShortStatic : kQuickSet16Static);
739       break;
740     case DataType::Type::kUint16:
741       entrypoint = is_instance
742           ? (is_get ? kQuickGetCharInstance : kQuickSet16Instance)
743           : (is_get ? kQuickGetCharStatic : kQuickSet16Static);
744       break;
745     case DataType::Type::kInt32:
746     case DataType::Type::kFloat32:
747       entrypoint = is_instance
748           ? (is_get ? kQuickGet32Instance : kQuickSet32Instance)
749           : (is_get ? kQuickGet32Static : kQuickSet32Static);
750       break;
751     case DataType::Type::kReference:
752       entrypoint = is_instance
753           ? (is_get ? kQuickGetObjInstance : kQuickSetObjInstance)
754           : (is_get ? kQuickGetObjStatic : kQuickSetObjStatic);
755       break;
756     case DataType::Type::kInt64:
757     case DataType::Type::kFloat64:
758       entrypoint = is_instance
759           ? (is_get ? kQuickGet64Instance : kQuickSet64Instance)
760           : (is_get ? kQuickGet64Static : kQuickSet64Static);
761       break;
762     default:
763       LOG(FATAL) << "Invalid type " << field_type;
764   }
765   InvokeRuntime(entrypoint, field_access, dex_pc, nullptr);
766 
767   if (is_get && DataType::IsFloatingPointType(field_type)) {
768     MoveLocation(locations->Out(), calling_convention.GetReturnLocation(field_type), field_type);
769   }
770 }
771 
CreateLoadClassRuntimeCallLocationSummary(HLoadClass * cls,Location runtime_type_index_location,Location runtime_return_location)772 void CodeGenerator::CreateLoadClassRuntimeCallLocationSummary(HLoadClass* cls,
773                                                               Location runtime_type_index_location,
774                                                               Location runtime_return_location) {
775   DCHECK_EQ(cls->GetLoadKind(), HLoadClass::LoadKind::kRuntimeCall);
776   DCHECK_EQ(cls->InputCount(), 1u);
777   LocationSummary* locations = new (cls->GetBlock()->GetGraph()->GetAllocator()) LocationSummary(
778       cls, LocationSummary::kCallOnMainOnly);
779   locations->SetInAt(0, Location::NoLocation());
780   locations->AddTemp(runtime_type_index_location);
781   locations->SetOut(runtime_return_location);
782 }
783 
GenerateLoadClassRuntimeCall(HLoadClass * cls)784 void CodeGenerator::GenerateLoadClassRuntimeCall(HLoadClass* cls) {
785   DCHECK_EQ(cls->GetLoadKind(), HLoadClass::LoadKind::kRuntimeCall);
786   DCHECK(!cls->MustGenerateClinitCheck());
787   LocationSummary* locations = cls->GetLocations();
788   MoveConstant(locations->GetTemp(0), cls->GetTypeIndex().index_);
789   if (cls->NeedsAccessCheck()) {
790     CheckEntrypointTypes<kQuickResolveTypeAndVerifyAccess, void*, uint32_t>();
791     InvokeRuntime(kQuickResolveTypeAndVerifyAccess, cls, cls->GetDexPc());
792   } else {
793     CheckEntrypointTypes<kQuickResolveType, void*, uint32_t>();
794     InvokeRuntime(kQuickResolveType, cls, cls->GetDexPc());
795   }
796 }
797 
CreateLoadMethodHandleRuntimeCallLocationSummary(HLoadMethodHandle * method_handle,Location runtime_proto_index_location,Location runtime_return_location)798 void CodeGenerator::CreateLoadMethodHandleRuntimeCallLocationSummary(
799     HLoadMethodHandle* method_handle,
800     Location runtime_proto_index_location,
801     Location runtime_return_location) {
802   DCHECK_EQ(method_handle->InputCount(), 1u);
803   LocationSummary* locations =
804       new (method_handle->GetBlock()->GetGraph()->GetAllocator()) LocationSummary(
805           method_handle, LocationSummary::kCallOnMainOnly);
806   locations->SetInAt(0, Location::NoLocation());
807   locations->AddTemp(runtime_proto_index_location);
808   locations->SetOut(runtime_return_location);
809 }
810 
GenerateLoadMethodHandleRuntimeCall(HLoadMethodHandle * method_handle)811 void CodeGenerator::GenerateLoadMethodHandleRuntimeCall(HLoadMethodHandle* method_handle) {
812   LocationSummary* locations = method_handle->GetLocations();
813   MoveConstant(locations->GetTemp(0), method_handle->GetMethodHandleIndex());
814   CheckEntrypointTypes<kQuickResolveMethodHandle, void*, uint32_t>();
815   InvokeRuntime(kQuickResolveMethodHandle, method_handle, method_handle->GetDexPc());
816 }
817 
CreateLoadMethodTypeRuntimeCallLocationSummary(HLoadMethodType * method_type,Location runtime_proto_index_location,Location runtime_return_location)818 void CodeGenerator::CreateLoadMethodTypeRuntimeCallLocationSummary(
819     HLoadMethodType* method_type,
820     Location runtime_proto_index_location,
821     Location runtime_return_location) {
822   DCHECK_EQ(method_type->InputCount(), 1u);
823   LocationSummary* locations =
824       new (method_type->GetBlock()->GetGraph()->GetAllocator()) LocationSummary(
825           method_type, LocationSummary::kCallOnMainOnly);
826   locations->SetInAt(0, Location::NoLocation());
827   locations->AddTemp(runtime_proto_index_location);
828   locations->SetOut(runtime_return_location);
829 }
830 
GenerateLoadMethodTypeRuntimeCall(HLoadMethodType * method_type)831 void CodeGenerator::GenerateLoadMethodTypeRuntimeCall(HLoadMethodType* method_type) {
832   LocationSummary* locations = method_type->GetLocations();
833   MoveConstant(locations->GetTemp(0), method_type->GetProtoIndex().index_);
834   CheckEntrypointTypes<kQuickResolveMethodType, void*, uint32_t>();
835   InvokeRuntime(kQuickResolveMethodType, method_type, method_type->GetDexPc());
836 }
837 
GetBootImageOffsetImpl(const void * object,ImageHeader::ImageSections section)838 static uint32_t GetBootImageOffsetImpl(const void* object, ImageHeader::ImageSections section) {
839   Runtime* runtime = Runtime::Current();
840   DCHECK(runtime->IsAotCompiler());
841   const std::vector<gc::space::ImageSpace*>& boot_image_spaces =
842       runtime->GetHeap()->GetBootImageSpaces();
843   // Check that the `object` is in the expected section of one of the boot image files.
844   DCHECK(std::any_of(boot_image_spaces.begin(),
845                      boot_image_spaces.end(),
846                      [object, section](gc::space::ImageSpace* space) {
847                        uintptr_t begin = reinterpret_cast<uintptr_t>(space->Begin());
848                        uintptr_t offset = reinterpret_cast<uintptr_t>(object) - begin;
849                        return space->GetImageHeader().GetImageSection(section).Contains(offset);
850                      }));
851   uintptr_t begin = reinterpret_cast<uintptr_t>(boot_image_spaces.front()->Begin());
852   uintptr_t offset = reinterpret_cast<uintptr_t>(object) - begin;
853   return dchecked_integral_cast<uint32_t>(offset);
854 }
855 
856 // NO_THREAD_SAFETY_ANALYSIS: Avoid taking the mutator lock, boot image classes are non-moveable.
GetBootImageOffset(HLoadClass * load_class)857 uint32_t CodeGenerator::GetBootImageOffset(HLoadClass* load_class) NO_THREAD_SAFETY_ANALYSIS {
858   DCHECK_EQ(load_class->GetLoadKind(), HLoadClass::LoadKind::kBootImageRelRo);
859   ObjPtr<mirror::Class> klass = load_class->GetClass().Get();
860   DCHECK(klass != nullptr);
861   return GetBootImageOffsetImpl(klass.Ptr(), ImageHeader::kSectionObjects);
862 }
863 
864 // NO_THREAD_SAFETY_ANALYSIS: Avoid taking the mutator lock, boot image strings are non-moveable.
GetBootImageOffset(HLoadString * load_string)865 uint32_t CodeGenerator::GetBootImageOffset(HLoadString* load_string) NO_THREAD_SAFETY_ANALYSIS {
866   DCHECK_EQ(load_string->GetLoadKind(), HLoadString::LoadKind::kBootImageRelRo);
867   ObjPtr<mirror::String> string = load_string->GetString().Get();
868   DCHECK(string != nullptr);
869   return GetBootImageOffsetImpl(string.Ptr(), ImageHeader::kSectionObjects);
870 }
871 
GetBootImageOffset(HInvokeStaticOrDirect * invoke)872 uint32_t CodeGenerator::GetBootImageOffset(HInvokeStaticOrDirect* invoke) {
873   DCHECK_EQ(invoke->GetMethodLoadKind(), HInvokeStaticOrDirect::MethodLoadKind::kBootImageRelRo);
874   ArtMethod* method = invoke->GetResolvedMethod();
875   DCHECK(method != nullptr);
876   return GetBootImageOffsetImpl(method, ImageHeader::kSectionArtMethods);
877 }
878 
BlockIfInRegister(Location location,bool is_out) const879 void CodeGenerator::BlockIfInRegister(Location location, bool is_out) const {
880   // The DCHECKS below check that a register is not specified twice in
881   // the summary. The out location can overlap with an input, so we need
882   // to special case it.
883   if (location.IsRegister()) {
884     DCHECK(is_out || !blocked_core_registers_[location.reg()]);
885     blocked_core_registers_[location.reg()] = true;
886   } else if (location.IsFpuRegister()) {
887     DCHECK(is_out || !blocked_fpu_registers_[location.reg()]);
888     blocked_fpu_registers_[location.reg()] = true;
889   } else if (location.IsFpuRegisterPair()) {
890     DCHECK(is_out || !blocked_fpu_registers_[location.AsFpuRegisterPairLow<int>()]);
891     blocked_fpu_registers_[location.AsFpuRegisterPairLow<int>()] = true;
892     DCHECK(is_out || !blocked_fpu_registers_[location.AsFpuRegisterPairHigh<int>()]);
893     blocked_fpu_registers_[location.AsFpuRegisterPairHigh<int>()] = true;
894   } else if (location.IsRegisterPair()) {
895     DCHECK(is_out || !blocked_core_registers_[location.AsRegisterPairLow<int>()]);
896     blocked_core_registers_[location.AsRegisterPairLow<int>()] = true;
897     DCHECK(is_out || !blocked_core_registers_[location.AsRegisterPairHigh<int>()]);
898     blocked_core_registers_[location.AsRegisterPairHigh<int>()] = true;
899   }
900 }
901 
AllocateLocations(HInstruction * instruction)902 void CodeGenerator::AllocateLocations(HInstruction* instruction) {
903   for (HEnvironment* env = instruction->GetEnvironment(); env != nullptr; env = env->GetParent()) {
904     env->AllocateLocations();
905   }
906   instruction->Accept(GetLocationBuilder());
907   DCHECK(CheckTypeConsistency(instruction));
908   LocationSummary* locations = instruction->GetLocations();
909   if (!instruction->IsSuspendCheckEntry()) {
910     if (locations != nullptr) {
911       if (locations->CanCall()) {
912         MarkNotLeaf();
913       } else if (locations->Intrinsified() &&
914                  instruction->IsInvokeStaticOrDirect() &&
915                  !instruction->AsInvokeStaticOrDirect()->HasCurrentMethodInput()) {
916         // A static method call that has been fully intrinsified, and cannot call on the slow
917         // path or refer to the current method directly, no longer needs current method.
918         return;
919       }
920     }
921     if (instruction->NeedsCurrentMethod()) {
922       SetRequiresCurrentMethod();
923     }
924   }
925 }
926 
Create(HGraph * graph,const CompilerOptions & compiler_options,OptimizingCompilerStats * stats)927 std::unique_ptr<CodeGenerator> CodeGenerator::Create(HGraph* graph,
928                                                      const CompilerOptions& compiler_options,
929                                                      OptimizingCompilerStats* stats) {
930   ArenaAllocator* allocator = graph->GetAllocator();
931   switch (compiler_options.GetInstructionSet()) {
932 #ifdef ART_ENABLE_CODEGEN_arm
933     case InstructionSet::kArm:
934     case InstructionSet::kThumb2: {
935       return std::unique_ptr<CodeGenerator>(
936           new (allocator) arm::CodeGeneratorARMVIXL(graph, compiler_options, stats));
937     }
938 #endif
939 #ifdef ART_ENABLE_CODEGEN_arm64
940     case InstructionSet::kArm64: {
941       return std::unique_ptr<CodeGenerator>(
942           new (allocator) arm64::CodeGeneratorARM64(graph, compiler_options, stats));
943     }
944 #endif
945 #ifdef ART_ENABLE_CODEGEN_x86
946     case InstructionSet::kX86: {
947       return std::unique_ptr<CodeGenerator>(
948           new (allocator) x86::CodeGeneratorX86(graph, compiler_options, stats));
949     }
950 #endif
951 #ifdef ART_ENABLE_CODEGEN_x86_64
952     case InstructionSet::kX86_64: {
953       return std::unique_ptr<CodeGenerator>(
954           new (allocator) x86_64::CodeGeneratorX86_64(graph, compiler_options, stats));
955     }
956 #endif
957     default:
958       return nullptr;
959   }
960 }
961 
CodeGenerator(HGraph * graph,size_t number_of_core_registers,size_t number_of_fpu_registers,size_t number_of_register_pairs,uint32_t core_callee_save_mask,uint32_t fpu_callee_save_mask,const CompilerOptions & compiler_options,OptimizingCompilerStats * stats)962 CodeGenerator::CodeGenerator(HGraph* graph,
963                              size_t number_of_core_registers,
964                              size_t number_of_fpu_registers,
965                              size_t number_of_register_pairs,
966                              uint32_t core_callee_save_mask,
967                              uint32_t fpu_callee_save_mask,
968                              const CompilerOptions& compiler_options,
969                              OptimizingCompilerStats* stats)
970     : frame_size_(0),
971       core_spill_mask_(0),
972       fpu_spill_mask_(0),
973       first_register_slot_in_slow_path_(0),
974       allocated_registers_(RegisterSet::Empty()),
975       blocked_core_registers_(graph->GetAllocator()->AllocArray<bool>(number_of_core_registers,
976                                                                       kArenaAllocCodeGenerator)),
977       blocked_fpu_registers_(graph->GetAllocator()->AllocArray<bool>(number_of_fpu_registers,
978                                                                      kArenaAllocCodeGenerator)),
979       number_of_core_registers_(number_of_core_registers),
980       number_of_fpu_registers_(number_of_fpu_registers),
981       number_of_register_pairs_(number_of_register_pairs),
982       core_callee_save_mask_(core_callee_save_mask),
983       fpu_callee_save_mask_(fpu_callee_save_mask),
984       block_order_(nullptr),
985       disasm_info_(nullptr),
986       stats_(stats),
987       graph_(graph),
988       compiler_options_(compiler_options),
989       current_slow_path_(nullptr),
990       current_block_index_(0),
991       is_leaf_(true),
992       requires_current_method_(false),
993       code_generation_data_() {
994   if (GetGraph()->IsCompilingOsr()) {
995     // Make OSR methods have all registers spilled, this simplifies the logic of
996     // jumping to the compiled code directly.
997     for (size_t i = 0; i < number_of_core_registers_; ++i) {
998       if (IsCoreCalleeSaveRegister(i)) {
999         AddAllocatedRegister(Location::RegisterLocation(i));
1000       }
1001     }
1002     for (size_t i = 0; i < number_of_fpu_registers_; ++i) {
1003       if (IsFloatingPointCalleeSaveRegister(i)) {
1004         AddAllocatedRegister(Location::FpuRegisterLocation(i));
1005       }
1006     }
1007   }
1008 }
1009 
~CodeGenerator()1010 CodeGenerator::~CodeGenerator() {}
1011 
GetNumberOfJitRoots() const1012 size_t CodeGenerator::GetNumberOfJitRoots() const {
1013   DCHECK(code_generation_data_ != nullptr);
1014   return code_generation_data_->GetNumberOfJitRoots();
1015 }
1016 
CheckCovers(uint32_t dex_pc,const HGraph & graph,const CodeInfo & code_info,const ArenaVector<HSuspendCheck * > & loop_headers,ArenaVector<size_t> * covered)1017 static void CheckCovers(uint32_t dex_pc,
1018                         const HGraph& graph,
1019                         const CodeInfo& code_info,
1020                         const ArenaVector<HSuspendCheck*>& loop_headers,
1021                         ArenaVector<size_t>* covered) {
1022   for (size_t i = 0; i < loop_headers.size(); ++i) {
1023     if (loop_headers[i]->GetDexPc() == dex_pc) {
1024       if (graph.IsCompilingOsr()) {
1025         DCHECK(code_info.GetOsrStackMapForDexPc(dex_pc).IsValid());
1026       }
1027       ++(*covered)[i];
1028     }
1029   }
1030 }
1031 
1032 // Debug helper to ensure loop entries in compiled code are matched by
1033 // dex branch instructions.
CheckLoopEntriesCanBeUsedForOsr(const HGraph & graph,const CodeInfo & code_info,const dex::CodeItem & code_item)1034 static void CheckLoopEntriesCanBeUsedForOsr(const HGraph& graph,
1035                                             const CodeInfo& code_info,
1036                                             const dex::CodeItem& code_item) {
1037   if (graph.HasTryCatch()) {
1038     // One can write loops through try/catch, which we do not support for OSR anyway.
1039     return;
1040   }
1041   ArenaVector<HSuspendCheck*> loop_headers(graph.GetAllocator()->Adapter(kArenaAllocMisc));
1042   for (HBasicBlock* block : graph.GetReversePostOrder()) {
1043     if (block->IsLoopHeader()) {
1044       HSuspendCheck* suspend_check = block->GetLoopInformation()->GetSuspendCheck();
1045       if (!suspend_check->GetEnvironment()->IsFromInlinedInvoke()) {
1046         loop_headers.push_back(suspend_check);
1047       }
1048     }
1049   }
1050   ArenaVector<size_t> covered(
1051       loop_headers.size(), 0, graph.GetAllocator()->Adapter(kArenaAllocMisc));
1052   for (const DexInstructionPcPair& pair : CodeItemInstructionAccessor(graph.GetDexFile(),
1053                                                                       &code_item)) {
1054     const uint32_t dex_pc = pair.DexPc();
1055     const Instruction& instruction = pair.Inst();
1056     if (instruction.IsBranch()) {
1057       uint32_t target = dex_pc + instruction.GetTargetOffset();
1058       CheckCovers(target, graph, code_info, loop_headers, &covered);
1059     } else if (instruction.IsSwitch()) {
1060       DexSwitchTable table(instruction, dex_pc);
1061       uint16_t num_entries = table.GetNumEntries();
1062       size_t offset = table.GetFirstValueIndex();
1063 
1064       // Use a larger loop counter type to avoid overflow issues.
1065       for (size_t i = 0; i < num_entries; ++i) {
1066         // The target of the case.
1067         uint32_t target = dex_pc + table.GetEntryAt(i + offset);
1068         CheckCovers(target, graph, code_info, loop_headers, &covered);
1069       }
1070     }
1071   }
1072 
1073   for (size_t i = 0; i < covered.size(); ++i) {
1074     DCHECK_NE(covered[i], 0u) << "Loop in compiled code has no dex branch equivalent";
1075   }
1076 }
1077 
BuildStackMaps(const dex::CodeItem * code_item)1078 ScopedArenaVector<uint8_t> CodeGenerator::BuildStackMaps(const dex::CodeItem* code_item) {
1079   ScopedArenaVector<uint8_t> stack_map = GetStackMapStream()->Encode();
1080   if (kIsDebugBuild && code_item != nullptr) {
1081     CheckLoopEntriesCanBeUsedForOsr(*graph_, CodeInfo(stack_map.data()), *code_item);
1082   }
1083   return stack_map;
1084 }
1085 
1086 // Returns whether stackmap dex register info is needed for the instruction.
1087 //
1088 // The following cases mandate having a dex register map:
1089 //  * Deoptimization
1090 //    when we need to obtain the values to restore actual vregisters for interpreter.
1091 //  * Debuggability
1092 //    when we want to observe the values / asynchronously deoptimize.
1093 //  * Monitor operations
1094 //    to allow dumping in a stack trace locked dex registers for non-debuggable code.
1095 //  * On-stack-replacement (OSR)
1096 //    when entering compiled for OSR code from the interpreter we need to initialize the compiled
1097 //    code values with the values from the vregisters.
1098 //  * Method local catch blocks
1099 //    a catch block must see the environment of the instruction from the same method that can
1100 //    throw to this block.
NeedsVregInfo(HInstruction * instruction,bool osr)1101 static bool NeedsVregInfo(HInstruction* instruction, bool osr) {
1102   HGraph* graph = instruction->GetBlock()->GetGraph();
1103   return instruction->IsDeoptimize() ||
1104          graph->IsDebuggable() ||
1105          graph->HasMonitorOperations() ||
1106          osr ||
1107          instruction->CanThrowIntoCatchBlock();
1108 }
1109 
RecordPcInfo(HInstruction * instruction,uint32_t dex_pc,SlowPathCode * slow_path,bool native_debug_info)1110 void CodeGenerator::RecordPcInfo(HInstruction* instruction,
1111                                  uint32_t dex_pc,
1112                                  SlowPathCode* slow_path,
1113                                  bool native_debug_info) {
1114   RecordPcInfo(instruction, dex_pc, GetAssembler()->CodePosition(), slow_path, native_debug_info);
1115 }
1116 
RecordPcInfo(HInstruction * instruction,uint32_t dex_pc,uint32_t native_pc,SlowPathCode * slow_path,bool native_debug_info)1117 void CodeGenerator::RecordPcInfo(HInstruction* instruction,
1118                                  uint32_t dex_pc,
1119                                  uint32_t native_pc,
1120                                  SlowPathCode* slow_path,
1121                                  bool native_debug_info) {
1122   if (instruction != nullptr) {
1123     // The code generated for some type conversions
1124     // may call the runtime, thus normally requiring a subsequent
1125     // call to this method. However, the method verifier does not
1126     // produce PC information for certain instructions, which are
1127     // considered "atomic" (they cannot join a GC).
1128     // Therefore we do not currently record PC information for such
1129     // instructions.  As this may change later, we added this special
1130     // case so that code generators may nevertheless call
1131     // CodeGenerator::RecordPcInfo without triggering an error in
1132     // CodeGenerator::BuildNativeGCMap ("Missing ref for dex pc 0x")
1133     // thereafter.
1134     if (instruction->IsTypeConversion()) {
1135       return;
1136     }
1137     if (instruction->IsRem()) {
1138       DataType::Type type = instruction->AsRem()->GetResultType();
1139       if ((type == DataType::Type::kFloat32) || (type == DataType::Type::kFloat64)) {
1140         return;
1141       }
1142     }
1143   }
1144 
1145   StackMapStream* stack_map_stream = GetStackMapStream();
1146   if (instruction == nullptr) {
1147     // For stack overflow checks and native-debug-info entries without dex register
1148     // mapping (i.e. start of basic block or start of slow path).
1149     stack_map_stream->BeginStackMapEntry(dex_pc, native_pc);
1150     stack_map_stream->EndStackMapEntry();
1151     return;
1152   }
1153 
1154   LocationSummary* locations = instruction->GetLocations();
1155   uint32_t register_mask = locations->GetRegisterMask();
1156   DCHECK_EQ(register_mask & ~locations->GetLiveRegisters()->GetCoreRegisters(), 0u);
1157   if (locations->OnlyCallsOnSlowPath()) {
1158     // In case of slow path, we currently set the location of caller-save registers
1159     // to register (instead of their stack location when pushed before the slow-path
1160     // call). Therefore register_mask contains both callee-save and caller-save
1161     // registers that hold objects. We must remove the spilled caller-save from the
1162     // mask, since they will be overwritten by the callee.
1163     uint32_t spills = GetSlowPathSpills(locations, /* core_registers= */ true);
1164     register_mask &= ~spills;
1165   } else {
1166     // The register mask must be a subset of callee-save registers.
1167     DCHECK_EQ(register_mask & core_callee_save_mask_, register_mask);
1168   }
1169 
1170   uint32_t outer_dex_pc = dex_pc;
1171   uint32_t outer_environment_size = 0u;
1172   uint32_t inlining_depth = 0;
1173   HEnvironment* const environment = instruction->GetEnvironment();
1174   if (environment != nullptr) {
1175     HEnvironment* outer_environment = environment;
1176     while (outer_environment->GetParent() != nullptr) {
1177       outer_environment = outer_environment->GetParent();
1178       ++inlining_depth;
1179     }
1180     outer_dex_pc = outer_environment->GetDexPc();
1181     outer_environment_size = outer_environment->Size();
1182   }
1183 
1184   HLoopInformation* info = instruction->GetBlock()->GetLoopInformation();
1185   bool osr =
1186       instruction->IsSuspendCheck() &&
1187       (info != nullptr) &&
1188       graph_->IsCompilingOsr() &&
1189       (inlining_depth == 0);
1190   StackMap::Kind kind = native_debug_info
1191       ? StackMap::Kind::Debug
1192       : (osr ? StackMap::Kind::OSR : StackMap::Kind::Default);
1193   bool needs_vreg_info = NeedsVregInfo(instruction, osr);
1194   stack_map_stream->BeginStackMapEntry(outer_dex_pc,
1195                                        native_pc,
1196                                        register_mask,
1197                                        locations->GetStackMask(),
1198                                        kind,
1199                                        needs_vreg_info);
1200 
1201   EmitEnvironment(environment, slow_path, needs_vreg_info);
1202   stack_map_stream->EndStackMapEntry();
1203 
1204   if (osr) {
1205     DCHECK_EQ(info->GetSuspendCheck(), instruction);
1206     DCHECK(info->IsIrreducible());
1207     DCHECK(environment != nullptr);
1208     if (kIsDebugBuild) {
1209       for (size_t i = 0, environment_size = environment->Size(); i < environment_size; ++i) {
1210         HInstruction* in_environment = environment->GetInstructionAt(i);
1211         if (in_environment != nullptr) {
1212           DCHECK(in_environment->IsPhi() || in_environment->IsConstant());
1213           Location location = environment->GetLocationAt(i);
1214           DCHECK(location.IsStackSlot() ||
1215                  location.IsDoubleStackSlot() ||
1216                  location.IsConstant() ||
1217                  location.IsInvalid());
1218           if (location.IsStackSlot() || location.IsDoubleStackSlot()) {
1219             DCHECK_LT(location.GetStackIndex(), static_cast<int32_t>(GetFrameSize()));
1220           }
1221         }
1222       }
1223     }
1224   }
1225 }
1226 
HasStackMapAtCurrentPc()1227 bool CodeGenerator::HasStackMapAtCurrentPc() {
1228   uint32_t pc = GetAssembler()->CodeSize();
1229   StackMapStream* stack_map_stream = GetStackMapStream();
1230   size_t count = stack_map_stream->GetNumberOfStackMaps();
1231   if (count == 0) {
1232     return false;
1233   }
1234   return stack_map_stream->GetStackMapNativePcOffset(count - 1) == pc;
1235 }
1236 
MaybeRecordNativeDebugInfo(HInstruction * instruction,uint32_t dex_pc,SlowPathCode * slow_path)1237 void CodeGenerator::MaybeRecordNativeDebugInfo(HInstruction* instruction,
1238                                                uint32_t dex_pc,
1239                                                SlowPathCode* slow_path) {
1240   if (GetCompilerOptions().GetNativeDebuggable() && dex_pc != kNoDexPc) {
1241     if (HasStackMapAtCurrentPc()) {
1242       // Ensure that we do not collide with the stack map of the previous instruction.
1243       GenerateNop();
1244     }
1245     RecordPcInfo(instruction, dex_pc, slow_path, /* native_debug_info= */ true);
1246   }
1247 }
1248 
RecordCatchBlockInfo()1249 void CodeGenerator::RecordCatchBlockInfo() {
1250   StackMapStream* stack_map_stream = GetStackMapStream();
1251 
1252   for (HBasicBlock* block : *block_order_) {
1253     if (!block->IsCatchBlock()) {
1254       continue;
1255     }
1256 
1257     uint32_t dex_pc = block->GetDexPc();
1258     uint32_t num_vregs = graph_->GetNumberOfVRegs();
1259     uint32_t native_pc = GetAddressOf(block);
1260 
1261     stack_map_stream->BeginStackMapEntry(dex_pc,
1262                                          native_pc,
1263                                          /* register_mask= */ 0,
1264                                          /* sp_mask= */ nullptr,
1265                                          StackMap::Kind::Catch);
1266 
1267     HInstruction* current_phi = block->GetFirstPhi();
1268     for (size_t vreg = 0; vreg < num_vregs; ++vreg) {
1269       while (current_phi != nullptr && current_phi->AsPhi()->GetRegNumber() < vreg) {
1270         HInstruction* next_phi = current_phi->GetNext();
1271         DCHECK(next_phi == nullptr ||
1272                current_phi->AsPhi()->GetRegNumber() <= next_phi->AsPhi()->GetRegNumber())
1273             << "Phis need to be sorted by vreg number to keep this a linear-time loop.";
1274         current_phi = next_phi;
1275       }
1276 
1277       if (current_phi == nullptr || current_phi->AsPhi()->GetRegNumber() != vreg) {
1278         stack_map_stream->AddDexRegisterEntry(DexRegisterLocation::Kind::kNone, 0);
1279       } else {
1280         Location location = current_phi->GetLocations()->Out();
1281         switch (location.GetKind()) {
1282           case Location::kStackSlot: {
1283             stack_map_stream->AddDexRegisterEntry(
1284                 DexRegisterLocation::Kind::kInStack, location.GetStackIndex());
1285             break;
1286           }
1287           case Location::kDoubleStackSlot: {
1288             stack_map_stream->AddDexRegisterEntry(
1289                 DexRegisterLocation::Kind::kInStack, location.GetStackIndex());
1290             stack_map_stream->AddDexRegisterEntry(
1291                 DexRegisterLocation::Kind::kInStack, location.GetHighStackIndex(kVRegSize));
1292             ++vreg;
1293             DCHECK_LT(vreg, num_vregs);
1294             break;
1295           }
1296           default: {
1297             // All catch phis must be allocated to a stack slot.
1298             LOG(FATAL) << "Unexpected kind " << location.GetKind();
1299             UNREACHABLE();
1300           }
1301         }
1302       }
1303     }
1304 
1305     stack_map_stream->EndStackMapEntry();
1306   }
1307 }
1308 
AddSlowPath(SlowPathCode * slow_path)1309 void CodeGenerator::AddSlowPath(SlowPathCode* slow_path) {
1310   DCHECK(code_generation_data_ != nullptr);
1311   code_generation_data_->AddSlowPath(slow_path);
1312 }
1313 
EmitVRegInfo(HEnvironment * environment,SlowPathCode * slow_path)1314 void CodeGenerator::EmitVRegInfo(HEnvironment* environment, SlowPathCode* slow_path) {
1315   StackMapStream* stack_map_stream = GetStackMapStream();
1316   // Walk over the environment, and record the location of dex registers.
1317   for (size_t i = 0, environment_size = environment->Size(); i < environment_size; ++i) {
1318     HInstruction* current = environment->GetInstructionAt(i);
1319     if (current == nullptr) {
1320       stack_map_stream->AddDexRegisterEntry(DexRegisterLocation::Kind::kNone, 0);
1321       continue;
1322     }
1323 
1324     using Kind = DexRegisterLocation::Kind;
1325     Location location = environment->GetLocationAt(i);
1326     switch (location.GetKind()) {
1327       case Location::kConstant: {
1328         DCHECK_EQ(current, location.GetConstant());
1329         if (current->IsLongConstant()) {
1330           int64_t value = current->AsLongConstant()->GetValue();
1331           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, Low32Bits(value));
1332           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, High32Bits(value));
1333           ++i;
1334           DCHECK_LT(i, environment_size);
1335         } else if (current->IsDoubleConstant()) {
1336           int64_t value = bit_cast<int64_t, double>(current->AsDoubleConstant()->GetValue());
1337           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, Low32Bits(value));
1338           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, High32Bits(value));
1339           ++i;
1340           DCHECK_LT(i, environment_size);
1341         } else if (current->IsIntConstant()) {
1342           int32_t value = current->AsIntConstant()->GetValue();
1343           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, value);
1344         } else if (current->IsNullConstant()) {
1345           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, 0);
1346         } else {
1347           DCHECK(current->IsFloatConstant()) << current->DebugName();
1348           int32_t value = bit_cast<int32_t, float>(current->AsFloatConstant()->GetValue());
1349           stack_map_stream->AddDexRegisterEntry(Kind::kConstant, value);
1350         }
1351         break;
1352       }
1353 
1354       case Location::kStackSlot: {
1355         stack_map_stream->AddDexRegisterEntry(Kind::kInStack, location.GetStackIndex());
1356         break;
1357       }
1358 
1359       case Location::kDoubleStackSlot: {
1360         stack_map_stream->AddDexRegisterEntry(Kind::kInStack, location.GetStackIndex());
1361         stack_map_stream->AddDexRegisterEntry(
1362             Kind::kInStack, location.GetHighStackIndex(kVRegSize));
1363         ++i;
1364         DCHECK_LT(i, environment_size);
1365         break;
1366       }
1367 
1368       case Location::kRegister : {
1369         int id = location.reg();
1370         if (slow_path != nullptr && slow_path->IsCoreRegisterSaved(id)) {
1371           uint32_t offset = slow_path->GetStackOffsetOfCoreRegister(id);
1372           stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset);
1373           if (current->GetType() == DataType::Type::kInt64) {
1374             stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset + kVRegSize);
1375             ++i;
1376             DCHECK_LT(i, environment_size);
1377           }
1378         } else {
1379           stack_map_stream->AddDexRegisterEntry(Kind::kInRegister, id);
1380           if (current->GetType() == DataType::Type::kInt64) {
1381             stack_map_stream->AddDexRegisterEntry(Kind::kInRegisterHigh, id);
1382             ++i;
1383             DCHECK_LT(i, environment_size);
1384           }
1385         }
1386         break;
1387       }
1388 
1389       case Location::kFpuRegister : {
1390         int id = location.reg();
1391         if (slow_path != nullptr && slow_path->IsFpuRegisterSaved(id)) {
1392           uint32_t offset = slow_path->GetStackOffsetOfFpuRegister(id);
1393           stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset);
1394           if (current->GetType() == DataType::Type::kFloat64) {
1395             stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset + kVRegSize);
1396             ++i;
1397             DCHECK_LT(i, environment_size);
1398           }
1399         } else {
1400           stack_map_stream->AddDexRegisterEntry(Kind::kInFpuRegister, id);
1401           if (current->GetType() == DataType::Type::kFloat64) {
1402             stack_map_stream->AddDexRegisterEntry(Kind::kInFpuRegisterHigh, id);
1403             ++i;
1404             DCHECK_LT(i, environment_size);
1405           }
1406         }
1407         break;
1408       }
1409 
1410       case Location::kFpuRegisterPair : {
1411         int low = location.low();
1412         int high = location.high();
1413         if (slow_path != nullptr && slow_path->IsFpuRegisterSaved(low)) {
1414           uint32_t offset = slow_path->GetStackOffsetOfFpuRegister(low);
1415           stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset);
1416         } else {
1417           stack_map_stream->AddDexRegisterEntry(Kind::kInFpuRegister, low);
1418         }
1419         if (slow_path != nullptr && slow_path->IsFpuRegisterSaved(high)) {
1420           uint32_t offset = slow_path->GetStackOffsetOfFpuRegister(high);
1421           stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset);
1422           ++i;
1423         } else {
1424           stack_map_stream->AddDexRegisterEntry(Kind::kInFpuRegister, high);
1425           ++i;
1426         }
1427         DCHECK_LT(i, environment_size);
1428         break;
1429       }
1430 
1431       case Location::kRegisterPair : {
1432         int low = location.low();
1433         int high = location.high();
1434         if (slow_path != nullptr && slow_path->IsCoreRegisterSaved(low)) {
1435           uint32_t offset = slow_path->GetStackOffsetOfCoreRegister(low);
1436           stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset);
1437         } else {
1438           stack_map_stream->AddDexRegisterEntry(Kind::kInRegister, low);
1439         }
1440         if (slow_path != nullptr && slow_path->IsCoreRegisterSaved(high)) {
1441           uint32_t offset = slow_path->GetStackOffsetOfCoreRegister(high);
1442           stack_map_stream->AddDexRegisterEntry(Kind::kInStack, offset);
1443         } else {
1444           stack_map_stream->AddDexRegisterEntry(Kind::kInRegister, high);
1445         }
1446         ++i;
1447         DCHECK_LT(i, environment_size);
1448         break;
1449       }
1450 
1451       case Location::kInvalid: {
1452         stack_map_stream->AddDexRegisterEntry(Kind::kNone, 0);
1453         break;
1454       }
1455 
1456       default:
1457         LOG(FATAL) << "Unexpected kind " << location.GetKind();
1458     }
1459   }
1460 }
1461 
EmitEnvironment(HEnvironment * environment,SlowPathCode * slow_path,bool needs_vreg_info)1462 void CodeGenerator::EmitEnvironment(HEnvironment* environment,
1463                                     SlowPathCode* slow_path,
1464                                     bool needs_vreg_info) {
1465   if (environment == nullptr) return;
1466 
1467   StackMapStream* stack_map_stream = GetStackMapStream();
1468   bool emit_inline_info = environment->GetParent() != nullptr;
1469 
1470   if (emit_inline_info) {
1471     // We emit the parent environment first.
1472     EmitEnvironment(environment->GetParent(), slow_path, needs_vreg_info);
1473     stack_map_stream->BeginInlineInfoEntry(environment->GetMethod(),
1474                                            environment->GetDexPc(),
1475                                            needs_vreg_info ? environment->Size() : 0,
1476                                            &graph_->GetDexFile());
1477   }
1478 
1479   if (needs_vreg_info) {
1480     // If a dex register map is not required we just won't emit it.
1481     EmitVRegInfo(environment, slow_path);
1482   }
1483 
1484   if (emit_inline_info) {
1485     stack_map_stream->EndInlineInfoEntry();
1486   }
1487 }
1488 
CanMoveNullCheckToUser(HNullCheck * null_check)1489 bool CodeGenerator::CanMoveNullCheckToUser(HNullCheck* null_check) {
1490   return null_check->IsEmittedAtUseSite();
1491 }
1492 
MaybeRecordImplicitNullCheck(HInstruction * instr)1493 void CodeGenerator::MaybeRecordImplicitNullCheck(HInstruction* instr) {
1494   HNullCheck* null_check = instr->GetImplicitNullCheck();
1495   if (null_check != nullptr) {
1496     RecordPcInfo(null_check, null_check->GetDexPc(), GetAssembler()->CodePosition());
1497   }
1498 }
1499 
CreateThrowingSlowPathLocations(HInstruction * instruction,RegisterSet caller_saves)1500 LocationSummary* CodeGenerator::CreateThrowingSlowPathLocations(HInstruction* instruction,
1501                                                                 RegisterSet caller_saves) {
1502   // Note: Using kNoCall allows the method to be treated as leaf (and eliminate the
1503   // HSuspendCheck from entry block). However, it will still get a valid stack frame
1504   // because the HNullCheck needs an environment.
1505   LocationSummary::CallKind call_kind = LocationSummary::kNoCall;
1506   // When throwing from a try block, we may need to retrieve dalvik registers from
1507   // physical registers and we also need to set up stack mask for GC. This is
1508   // implicitly achieved by passing kCallOnSlowPath to the LocationSummary.
1509   bool can_throw_into_catch_block = instruction->CanThrowIntoCatchBlock();
1510   if (can_throw_into_catch_block) {
1511     call_kind = LocationSummary::kCallOnSlowPath;
1512   }
1513   LocationSummary* locations =
1514       new (GetGraph()->GetAllocator()) LocationSummary(instruction, call_kind);
1515   if (can_throw_into_catch_block && compiler_options_.GetImplicitNullChecks()) {
1516     locations->SetCustomSlowPathCallerSaves(caller_saves);  // Default: no caller-save registers.
1517   }
1518   DCHECK(!instruction->HasUses());
1519   return locations;
1520 }
1521 
GenerateNullCheck(HNullCheck * instruction)1522 void CodeGenerator::GenerateNullCheck(HNullCheck* instruction) {
1523   if (compiler_options_.GetImplicitNullChecks()) {
1524     MaybeRecordStat(stats_, MethodCompilationStat::kImplicitNullCheckGenerated);
1525     GenerateImplicitNullCheck(instruction);
1526   } else {
1527     MaybeRecordStat(stats_, MethodCompilationStat::kExplicitNullCheckGenerated);
1528     GenerateExplicitNullCheck(instruction);
1529   }
1530 }
1531 
ClearSpillSlotsFromLoopPhisInStackMap(HSuspendCheck * suspend_check,HParallelMove * spills) const1532 void CodeGenerator::ClearSpillSlotsFromLoopPhisInStackMap(HSuspendCheck* suspend_check,
1533                                                           HParallelMove* spills) const {
1534   LocationSummary* locations = suspend_check->GetLocations();
1535   HBasicBlock* block = suspend_check->GetBlock();
1536   DCHECK(block->GetLoopInformation()->GetSuspendCheck() == suspend_check);
1537   DCHECK(block->IsLoopHeader());
1538   DCHECK(block->GetFirstInstruction() == spills);
1539 
1540   for (size_t i = 0, num_moves = spills->NumMoves(); i != num_moves; ++i) {
1541     Location dest = spills->MoveOperandsAt(i)->GetDestination();
1542     // All parallel moves in loop headers are spills.
1543     DCHECK(dest.IsStackSlot() || dest.IsDoubleStackSlot() || dest.IsSIMDStackSlot()) << dest;
1544     // Clear the stack bit marking a reference. Do not bother to check if the spill is
1545     // actually a reference spill, clearing bits that are already zero is harmless.
1546     locations->ClearStackBit(dest.GetStackIndex() / kVRegSize);
1547   }
1548 }
1549 
EmitParallelMoves(Location from1,Location to1,DataType::Type type1,Location from2,Location to2,DataType::Type type2)1550 void CodeGenerator::EmitParallelMoves(Location from1,
1551                                       Location to1,
1552                                       DataType::Type type1,
1553                                       Location from2,
1554                                       Location to2,
1555                                       DataType::Type type2) {
1556   HParallelMove parallel_move(GetGraph()->GetAllocator());
1557   parallel_move.AddMove(from1, to1, type1, nullptr);
1558   parallel_move.AddMove(from2, to2, type2, nullptr);
1559   GetMoveResolver()->EmitNativeCode(&parallel_move);
1560 }
1561 
ValidateInvokeRuntime(QuickEntrypointEnum entrypoint,HInstruction * instruction,SlowPathCode * slow_path)1562 void CodeGenerator::ValidateInvokeRuntime(QuickEntrypointEnum entrypoint,
1563                                           HInstruction* instruction,
1564                                           SlowPathCode* slow_path) {
1565   // Ensure that the call kind indication given to the register allocator is
1566   // coherent with the runtime call generated.
1567   if (slow_path == nullptr) {
1568     DCHECK(instruction->GetLocations()->WillCall())
1569         << "instruction->DebugName()=" << instruction->DebugName();
1570   } else {
1571     DCHECK(instruction->GetLocations()->CallsOnSlowPath() || slow_path->IsFatal())
1572         << "instruction->DebugName()=" << instruction->DebugName()
1573         << " slow_path->GetDescription()=" << slow_path->GetDescription();
1574   }
1575 
1576   // Check that the GC side effect is set when required.
1577   // TODO: Reverse EntrypointCanTriggerGC
1578   if (EntrypointCanTriggerGC(entrypoint)) {
1579     if (slow_path == nullptr) {
1580       DCHECK(instruction->GetSideEffects().Includes(SideEffects::CanTriggerGC()))
1581           << "instruction->DebugName()=" << instruction->DebugName()
1582           << " instruction->GetSideEffects().ToString()="
1583           << instruction->GetSideEffects().ToString();
1584     } else {
1585       // 'CanTriggerGC' side effect is used to restrict optimization of instructions which depend
1586       // on GC (e.g. IntermediateAddress) - to ensure they are not alive across GC points. However
1587       // if execution never returns to the compiled code from a GC point this restriction is
1588       // unnecessary - in particular for fatal slow paths which might trigger GC.
1589       DCHECK((slow_path->IsFatal() && !instruction->GetLocations()->WillCall()) ||
1590              instruction->GetSideEffects().Includes(SideEffects::CanTriggerGC()) ||
1591              // When (non-Baker) read barriers are enabled, some instructions
1592              // use a slow path to emit a read barrier, which does not trigger
1593              // GC.
1594              (kEmitCompilerReadBarrier &&
1595               !kUseBakerReadBarrier &&
1596               (instruction->IsInstanceFieldGet() ||
1597                instruction->IsStaticFieldGet() ||
1598                instruction->IsArrayGet() ||
1599                instruction->IsLoadClass() ||
1600                instruction->IsLoadString() ||
1601                instruction->IsInstanceOf() ||
1602                instruction->IsCheckCast() ||
1603                (instruction->IsInvokeVirtual() && instruction->GetLocations()->Intrinsified()))))
1604           << "instruction->DebugName()=" << instruction->DebugName()
1605           << " instruction->GetSideEffects().ToString()="
1606           << instruction->GetSideEffects().ToString()
1607           << " slow_path->GetDescription()=" << slow_path->GetDescription();
1608     }
1609   } else {
1610     // The GC side effect is not required for the instruction. But the instruction might still have
1611     // it, for example if it calls other entrypoints requiring it.
1612   }
1613 
1614   // Check the coherency of leaf information.
1615   DCHECK(instruction->IsSuspendCheck()
1616          || ((slow_path != nullptr) && slow_path->IsFatal())
1617          || instruction->GetLocations()->CanCall()
1618          || !IsLeafMethod())
1619       << instruction->DebugName() << ((slow_path != nullptr) ? slow_path->GetDescription() : "");
1620 }
1621 
ValidateInvokeRuntimeWithoutRecordingPcInfo(HInstruction * instruction,SlowPathCode * slow_path)1622 void CodeGenerator::ValidateInvokeRuntimeWithoutRecordingPcInfo(HInstruction* instruction,
1623                                                                 SlowPathCode* slow_path) {
1624   DCHECK(instruction->GetLocations()->OnlyCallsOnSlowPath())
1625       << "instruction->DebugName()=" << instruction->DebugName()
1626       << " slow_path->GetDescription()=" << slow_path->GetDescription();
1627   // Only the Baker read barrier marking slow path used by certains
1628   // instructions is expected to invoke the runtime without recording
1629   // PC-related information.
1630   DCHECK(kUseBakerReadBarrier);
1631   DCHECK(instruction->IsInstanceFieldGet() ||
1632          instruction->IsStaticFieldGet() ||
1633          instruction->IsArrayGet() ||
1634          instruction->IsArraySet() ||
1635          instruction->IsLoadClass() ||
1636          instruction->IsLoadString() ||
1637          instruction->IsInstanceOf() ||
1638          instruction->IsCheckCast() ||
1639          (instruction->IsInvokeVirtual() && instruction->GetLocations()->Intrinsified()) ||
1640          (instruction->IsInvokeStaticOrDirect() && instruction->GetLocations()->Intrinsified()))
1641       << "instruction->DebugName()=" << instruction->DebugName()
1642       << " slow_path->GetDescription()=" << slow_path->GetDescription();
1643 }
1644 
SaveLiveRegisters(CodeGenerator * codegen,LocationSummary * locations)1645 void SlowPathCode::SaveLiveRegisters(CodeGenerator* codegen, LocationSummary* locations) {
1646   size_t stack_offset = codegen->GetFirstRegisterSlotInSlowPath();
1647 
1648   const uint32_t core_spills = codegen->GetSlowPathSpills(locations, /* core_registers= */ true);
1649   for (uint32_t i : LowToHighBits(core_spills)) {
1650     // If the register holds an object, update the stack mask.
1651     if (locations->RegisterContainsObject(i)) {
1652       locations->SetStackBit(stack_offset / kVRegSize);
1653     }
1654     DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
1655     DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
1656     saved_core_stack_offsets_[i] = stack_offset;
1657     stack_offset += codegen->SaveCoreRegister(stack_offset, i);
1658   }
1659 
1660   const uint32_t fp_spills = codegen->GetSlowPathSpills(locations, /* core_registers= */ false);
1661   for (uint32_t i : LowToHighBits(fp_spills)) {
1662     DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
1663     DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
1664     saved_fpu_stack_offsets_[i] = stack_offset;
1665     stack_offset += codegen->SaveFloatingPointRegister(stack_offset, i);
1666   }
1667 }
1668 
RestoreLiveRegisters(CodeGenerator * codegen,LocationSummary * locations)1669 void SlowPathCode::RestoreLiveRegisters(CodeGenerator* codegen, LocationSummary* locations) {
1670   size_t stack_offset = codegen->GetFirstRegisterSlotInSlowPath();
1671 
1672   const uint32_t core_spills = codegen->GetSlowPathSpills(locations, /* core_registers= */ true);
1673   for (uint32_t i : LowToHighBits(core_spills)) {
1674     DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
1675     DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
1676     stack_offset += codegen->RestoreCoreRegister(stack_offset, i);
1677   }
1678 
1679   const uint32_t fp_spills = codegen->GetSlowPathSpills(locations, /* core_registers= */ false);
1680   for (uint32_t i : LowToHighBits(fp_spills)) {
1681     DCHECK_LT(stack_offset, codegen->GetFrameSize() - codegen->FrameEntrySpillSize());
1682     DCHECK_LT(i, kMaximumNumberOfExpectedRegisters);
1683     stack_offset += codegen->RestoreFloatingPointRegister(stack_offset, i);
1684   }
1685 }
1686 
CreateSystemArrayCopyLocationSummary(HInvoke * invoke)1687 void CodeGenerator::CreateSystemArrayCopyLocationSummary(HInvoke* invoke) {
1688   // Check to see if we have known failures that will cause us to have to bail out
1689   // to the runtime, and just generate the runtime call directly.
1690   HIntConstant* src_pos = invoke->InputAt(1)->AsIntConstant();
1691   HIntConstant* dest_pos = invoke->InputAt(3)->AsIntConstant();
1692 
1693   // The positions must be non-negative.
1694   if ((src_pos != nullptr && src_pos->GetValue() < 0) ||
1695       (dest_pos != nullptr && dest_pos->GetValue() < 0)) {
1696     // We will have to fail anyways.
1697     return;
1698   }
1699 
1700   // The length must be >= 0.
1701   HIntConstant* length = invoke->InputAt(4)->AsIntConstant();
1702   if (length != nullptr) {
1703     int32_t len = length->GetValue();
1704     if (len < 0) {
1705       // Just call as normal.
1706       return;
1707     }
1708   }
1709 
1710   SystemArrayCopyOptimizations optimizations(invoke);
1711 
1712   if (optimizations.GetDestinationIsSource()) {
1713     if (src_pos != nullptr && dest_pos != nullptr && src_pos->GetValue() < dest_pos->GetValue()) {
1714       // We only support backward copying if source and destination are the same.
1715       return;
1716     }
1717   }
1718 
1719   if (optimizations.GetDestinationIsPrimitiveArray() || optimizations.GetSourceIsPrimitiveArray()) {
1720     // We currently don't intrinsify primitive copying.
1721     return;
1722   }
1723 
1724   ArenaAllocator* allocator = invoke->GetBlock()->GetGraph()->GetAllocator();
1725   LocationSummary* locations = new (allocator) LocationSummary(invoke,
1726                                                                LocationSummary::kCallOnSlowPath,
1727                                                                kIntrinsified);
1728   // arraycopy(Object src, int src_pos, Object dest, int dest_pos, int length).
1729   locations->SetInAt(0, Location::RequiresRegister());
1730   locations->SetInAt(1, Location::RegisterOrConstant(invoke->InputAt(1)));
1731   locations->SetInAt(2, Location::RequiresRegister());
1732   locations->SetInAt(3, Location::RegisterOrConstant(invoke->InputAt(3)));
1733   locations->SetInAt(4, Location::RegisterOrConstant(invoke->InputAt(4)));
1734 
1735   locations->AddTemp(Location::RequiresRegister());
1736   locations->AddTemp(Location::RequiresRegister());
1737   locations->AddTemp(Location::RequiresRegister());
1738 }
1739 
EmitJitRoots(uint8_t * code,const uint8_t * roots_data,std::vector<Handle<mirror::Object>> * roots)1740 void CodeGenerator::EmitJitRoots(uint8_t* code,
1741                                  const uint8_t* roots_data,
1742                                  /*out*/std::vector<Handle<mirror::Object>>* roots) {
1743   code_generation_data_->EmitJitRoots(roots);
1744   EmitJitRootPatches(code, roots_data);
1745 }
1746 
GetArrayAllocationEntrypoint(HNewArray * new_array)1747 QuickEntrypointEnum CodeGenerator::GetArrayAllocationEntrypoint(HNewArray* new_array) {
1748   switch (new_array->GetComponentSizeShift()) {
1749     case 0: return kQuickAllocArrayResolved8;
1750     case 1: return kQuickAllocArrayResolved16;
1751     case 2: return kQuickAllocArrayResolved32;
1752     case 3: return kQuickAllocArrayResolved64;
1753   }
1754   LOG(FATAL) << "Unreachable";
1755   UNREACHABLE();
1756 }
1757 
1758 }  // namespace art
1759