1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/compiler/code-generator.h"
6 
7 #include "src/address-map.h"
8 #include "src/compiler/code-generator-impl.h"
9 #include "src/compiler/linkage.h"
10 #include "src/compiler/pipeline.h"
11 #include "src/frames-inl.h"
12 
13 namespace v8 {
14 namespace internal {
15 namespace compiler {
16 
17 class CodeGenerator::JumpTable final : public ZoneObject {
18  public:
JumpTable(JumpTable * next,Label ** targets,size_t target_count)19   JumpTable(JumpTable* next, Label** targets, size_t target_count)
20       : next_(next), targets_(targets), target_count_(target_count) {}
21 
label()22   Label* label() { return &label_; }
next() const23   JumpTable* next() const { return next_; }
targets() const24   Label** targets() const { return targets_; }
target_count() const25   size_t target_count() const { return target_count_; }
26 
27  private:
28   Label label_;
29   JumpTable* const next_;
30   Label** const targets_;
31   size_t const target_count_;
32 };
33 
34 
CodeGenerator(Frame * frame,Linkage * linkage,InstructionSequence * code,CompilationInfo * info)35 CodeGenerator::CodeGenerator(Frame* frame, Linkage* linkage,
36                              InstructionSequence* code, CompilationInfo* info)
37     : frame_access_state_(new (code->zone()) FrameAccessState(frame)),
38       linkage_(linkage),
39       code_(code),
40       info_(info),
41       labels_(zone()->NewArray<Label>(code->InstructionBlockCount())),
42       current_block_(RpoNumber::Invalid()),
43       current_source_position_(SourcePosition::Unknown()),
44       masm_(info->isolate(), nullptr, 0, CodeObjectRequired::kYes),
45       resolver_(this),
46       safepoints_(code->zone()),
47       handlers_(code->zone()),
48       deoptimization_states_(code->zone()),
49       deoptimization_literals_(code->zone()),
50       inlined_function_count_(0),
51       translations_(code->zone()),
52       last_lazy_deopt_pc_(0),
53       jump_tables_(nullptr),
54       ools_(nullptr),
55       osr_pc_offset_(-1) {
56   for (int i = 0; i < code->InstructionBlockCount(); ++i) {
57     new (&labels_[i]) Label;
58   }
59   if (code->ContainsCall()) {
60     frame->MarkNeedsFrame();
61   }
62 }
63 
64 
GenerateCode()65 Handle<Code> CodeGenerator::GenerateCode() {
66   CompilationInfo* info = this->info();
67 
68   // Open a frame scope to indicate that there is a frame on the stack.  The
69   // MANUAL indicates that the scope shouldn't actually generate code to set up
70   // the frame (that is done in AssemblePrologue).
71   FrameScope frame_scope(masm(), StackFrame::MANUAL);
72 
73   // Emit a code line info recording start event.
74   PositionsRecorder* recorder = masm()->positions_recorder();
75   LOG_CODE_EVENT(isolate(), CodeStartLinePosInfoRecordEvent(recorder));
76 
77   // Place function entry hook if requested to do so.
78   if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) {
79     ProfileEntryHookStub::MaybeCallEntryHook(masm());
80   }
81 
82   // Architecture-specific, linkage-specific prologue.
83   info->set_prologue_offset(masm()->pc_offset());
84   AssemblePrologue();
85 
86   // Define deoptimization literals for all inlined functions.
87   DCHECK_EQ(0u, deoptimization_literals_.size());
88   for (auto& inlined : info->inlined_functions()) {
89     if (!inlined.shared_info.is_identical_to(info->shared_info())) {
90       DefineDeoptimizationLiteral(inlined.shared_info);
91     }
92   }
93   inlined_function_count_ = deoptimization_literals_.size();
94 
95   // Define deoptimization literals for all unoptimized code objects of inlined
96   // functions. This ensures unoptimized code is kept alive by optimized code.
97   for (auto& inlined : info->inlined_functions()) {
98     if (!inlined.shared_info.is_identical_to(info->shared_info())) {
99       DefineDeoptimizationLiteral(inlined.inlined_code_object_root);
100     }
101   }
102 
103   // Assemble all non-deferred blocks, followed by deferred ones.
104   for (int deferred = 0; deferred < 2; ++deferred) {
105     for (auto const block : code()->instruction_blocks()) {
106       if (block->IsDeferred() == (deferred == 0)) {
107         continue;
108       }
109       // Align loop headers on 16-byte boundaries.
110       if (block->IsLoopHeader()) masm()->Align(16);
111       // Ensure lazy deopt doesn't patch handler entry points.
112       if (block->IsHandler()) EnsureSpaceForLazyDeopt();
113       // Bind a label for a block.
114       current_block_ = block->rpo_number();
115       if (FLAG_code_comments) {
116         // TODO(titzer): these code comments are a giant memory leak.
117         Vector<char> buffer = Vector<char>::New(200);
118         char* buffer_start = buffer.start();
119 
120         int next = SNPrintF(
121             buffer, "-- B%d start%s%s%s%s", block->rpo_number().ToInt(),
122             block->IsDeferred() ? " (deferred)" : "",
123             block->needs_frame() ? "" : " (no frame)",
124             block->must_construct_frame() ? " (construct frame)" : "",
125             block->must_deconstruct_frame() ? " (deconstruct frame)" : "");
126 
127         buffer = buffer.SubVector(next, buffer.length());
128 
129         if (block->IsLoopHeader()) {
130           next =
131               SNPrintF(buffer, " (loop up to %d)", block->loop_end().ToInt());
132           buffer = buffer.SubVector(next, buffer.length());
133         }
134         if (block->loop_header().IsValid()) {
135           next =
136               SNPrintF(buffer, " (in loop %d)", block->loop_header().ToInt());
137           buffer = buffer.SubVector(next, buffer.length());
138         }
139         SNPrintF(buffer, " --");
140         masm()->RecordComment(buffer_start);
141       }
142       masm()->bind(GetLabel(current_block_));
143       for (int i = block->code_start(); i < block->code_end(); ++i) {
144         AssembleInstruction(code()->InstructionAt(i));
145       }
146     }
147   }
148 
149   // Assemble all out-of-line code.
150   if (ools_) {
151     masm()->RecordComment("-- Out of line code --");
152     for (OutOfLineCode* ool = ools_; ool; ool = ool->next()) {
153       masm()->bind(ool->entry());
154       ool->Generate();
155       if (ool->exit()->is_bound()) masm()->jmp(ool->exit());
156     }
157   }
158 
159   // Ensure there is space for lazy deoptimization in the code.
160   if (info->ShouldEnsureSpaceForLazyDeopt()) {
161     int target_offset = masm()->pc_offset() + Deoptimizer::patch_size();
162     while (masm()->pc_offset() < target_offset) {
163       masm()->nop();
164     }
165   }
166 
167   FinishCode(masm());
168 
169   // Emit the jump tables.
170   if (jump_tables_) {
171     masm()->Align(kPointerSize);
172     for (JumpTable* table = jump_tables_; table; table = table->next()) {
173       masm()->bind(table->label());
174       AssembleJumpTable(table->targets(), table->target_count());
175     }
176   }
177 
178   safepoints()->Emit(masm(), frame()->GetSpillSlotCount());
179 
180   Handle<Code> result =
181       v8::internal::CodeGenerator::MakeCodeEpilogue(masm(), info);
182   result->set_is_turbofanned(true);
183   result->set_stack_slots(frame()->GetSpillSlotCount());
184   result->set_safepoint_table_offset(safepoints()->GetCodeOffset());
185 
186   // Emit exception handler table.
187   if (!handlers_.empty()) {
188     Handle<HandlerTable> table =
189         Handle<HandlerTable>::cast(isolate()->factory()->NewFixedArray(
190             HandlerTable::LengthForReturn(static_cast<int>(handlers_.size())),
191             TENURED));
192     for (size_t i = 0; i < handlers_.size(); ++i) {
193       int position = handlers_[i].handler->pos();
194       HandlerTable::CatchPrediction prediction = handlers_[i].caught_locally
195                                                      ? HandlerTable::CAUGHT
196                                                      : HandlerTable::UNCAUGHT;
197       table->SetReturnOffset(static_cast<int>(i), handlers_[i].pc_offset);
198       table->SetReturnHandler(static_cast<int>(i), position, prediction);
199     }
200     result->set_handler_table(*table);
201   }
202 
203   PopulateDeoptimizationData(result);
204 
205   // Ensure there is space for lazy deoptimization in the relocation info.
206   if (info->ShouldEnsureSpaceForLazyDeopt()) {
207     Deoptimizer::EnsureRelocSpaceForLazyDeoptimization(result);
208   }
209 
210   // Emit a code line info recording stop event.
211   void* line_info = recorder->DetachJITHandlerData();
212   LOG_CODE_EVENT(isolate(), CodeEndLinePosInfoRecordEvent(*result, line_info));
213 
214   return result;
215 }
216 
217 
IsNextInAssemblyOrder(RpoNumber block) const218 bool CodeGenerator::IsNextInAssemblyOrder(RpoNumber block) const {
219   return code()
220       ->InstructionBlockAt(current_block_)
221       ->ao_number()
222       .IsNext(code()->InstructionBlockAt(block)->ao_number());
223 }
224 
225 
RecordSafepoint(ReferenceMap * references,Safepoint::Kind kind,int arguments,Safepoint::DeoptMode deopt_mode)226 void CodeGenerator::RecordSafepoint(ReferenceMap* references,
227                                     Safepoint::Kind kind, int arguments,
228                                     Safepoint::DeoptMode deopt_mode) {
229   Safepoint safepoint =
230       safepoints()->DefineSafepoint(masm(), kind, arguments, deopt_mode);
231   int stackSlotToSpillSlotDelta =
232       frame()->GetTotalFrameSlotCount() - frame()->GetSpillSlotCount();
233   for (auto& operand : references->reference_operands()) {
234     if (operand.IsStackSlot()) {
235       int index = LocationOperand::cast(operand).index();
236       DCHECK(index >= 0);
237       // Safepoint table indices are 0-based from the beginning of the spill
238       // slot area, adjust appropriately.
239       index -= stackSlotToSpillSlotDelta;
240       safepoint.DefinePointerSlot(index, zone());
241     } else if (operand.IsRegister() && (kind & Safepoint::kWithRegisters)) {
242       Register reg = LocationOperand::cast(operand).GetRegister();
243       safepoint.DefinePointerRegister(reg, zone());
244     }
245   }
246 }
247 
248 
IsMaterializableFromFrame(Handle<HeapObject> object,int * offset_return)249 bool CodeGenerator::IsMaterializableFromFrame(Handle<HeapObject> object,
250                                               int* offset_return) {
251   if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) {
252     if (info()->has_context() && object.is_identical_to(info()->context()) &&
253         !info()->is_osr()) {
254       *offset_return = StandardFrameConstants::kContextOffset;
255       return true;
256     } else if (object.is_identical_to(info()->closure())) {
257       *offset_return = JavaScriptFrameConstants::kFunctionOffset;
258       return true;
259     }
260   }
261   return false;
262 }
263 
264 
IsMaterializableFromRoot(Handle<HeapObject> object,Heap::RootListIndex * index_return)265 bool CodeGenerator::IsMaterializableFromRoot(
266     Handle<HeapObject> object, Heap::RootListIndex* index_return) {
267   const CallDescriptor* incoming_descriptor =
268       linkage()->GetIncomingDescriptor();
269   if (incoming_descriptor->flags() & CallDescriptor::kCanUseRoots) {
270     RootIndexMap map(isolate());
271     int root_index = map.Lookup(*object);
272     if (root_index != RootIndexMap::kInvalidRootIndex) {
273       *index_return = static_cast<Heap::RootListIndex>(root_index);
274       return true;
275     }
276   }
277   return false;
278 }
279 
280 
AssembleInstruction(Instruction * instr)281 void CodeGenerator::AssembleInstruction(Instruction* instr) {
282   AssembleGaps(instr);
283   AssembleSourcePosition(instr);
284   // Assemble architecture-specific code for the instruction.
285   AssembleArchInstruction(instr);
286 
287   FlagsMode mode = FlagsModeField::decode(instr->opcode());
288   FlagsCondition condition = FlagsConditionField::decode(instr->opcode());
289   if (mode == kFlags_branch) {
290     // Assemble a branch after this instruction.
291     InstructionOperandConverter i(this, instr);
292     RpoNumber true_rpo = i.InputRpo(instr->InputCount() - 2);
293     RpoNumber false_rpo = i.InputRpo(instr->InputCount() - 1);
294 
295     if (true_rpo == false_rpo) {
296       // redundant branch.
297       if (!IsNextInAssemblyOrder(true_rpo)) {
298         AssembleArchJump(true_rpo);
299       }
300       return;
301     }
302     if (IsNextInAssemblyOrder(true_rpo)) {
303       // true block is next, can fall through if condition negated.
304       std::swap(true_rpo, false_rpo);
305       condition = NegateFlagsCondition(condition);
306     }
307     BranchInfo branch;
308     branch.condition = condition;
309     branch.true_label = GetLabel(true_rpo);
310     branch.false_label = GetLabel(false_rpo);
311     branch.fallthru = IsNextInAssemblyOrder(false_rpo);
312     // Assemble architecture-specific branch.
313     AssembleArchBranch(instr, &branch);
314   } else if (mode == kFlags_set) {
315     // Assemble a boolean materialization after this instruction.
316     AssembleArchBoolean(instr, condition);
317   }
318 }
319 
320 
AssembleSourcePosition(Instruction * instr)321 void CodeGenerator::AssembleSourcePosition(Instruction* instr) {
322   SourcePosition source_position;
323   if (!code()->GetSourcePosition(instr, &source_position)) return;
324   if (source_position == current_source_position_) return;
325   current_source_position_ = source_position;
326   if (source_position.IsUnknown()) return;
327   int code_pos = source_position.raw();
328   masm()->positions_recorder()->RecordPosition(code_pos);
329   masm()->positions_recorder()->WriteRecordedPositions();
330   if (FLAG_code_comments) {
331     Vector<char> buffer = Vector<char>::New(256);
332     CompilationInfo* info = this->info();
333     int ln = Script::GetLineNumber(info->script(), code_pos);
334     int cn = Script::GetColumnNumber(info->script(), code_pos);
335     if (info->script()->name()->IsString()) {
336       Handle<String> file(String::cast(info->script()->name()));
337       base::OS::SNPrintF(buffer.start(), buffer.length(), "-- %s:%d:%d --",
338                          file->ToCString().get(), ln, cn);
339     } else {
340       base::OS::SNPrintF(buffer.start(), buffer.length(),
341                          "-- <unknown>:%d:%d --", ln, cn);
342     }
343     masm()->RecordComment(buffer.start());
344   }
345 }
346 
347 
AssembleGaps(Instruction * instr)348 void CodeGenerator::AssembleGaps(Instruction* instr) {
349   for (int i = Instruction::FIRST_GAP_POSITION;
350        i <= Instruction::LAST_GAP_POSITION; i++) {
351     Instruction::GapPosition inner_pos =
352         static_cast<Instruction::GapPosition>(i);
353     ParallelMove* move = instr->GetParallelMove(inner_pos);
354     if (move != nullptr) resolver()->Resolve(move);
355   }
356 }
357 
358 
PopulateDeoptimizationData(Handle<Code> code_object)359 void CodeGenerator::PopulateDeoptimizationData(Handle<Code> code_object) {
360   CompilationInfo* info = this->info();
361   int deopt_count = static_cast<int>(deoptimization_states_.size());
362   if (deopt_count == 0 && !info->is_osr()) return;
363   Handle<DeoptimizationInputData> data =
364       DeoptimizationInputData::New(isolate(), deopt_count, TENURED);
365 
366   Handle<ByteArray> translation_array =
367       translations_.CreateByteArray(isolate()->factory());
368 
369   data->SetTranslationByteArray(*translation_array);
370   data->SetInlinedFunctionCount(
371       Smi::FromInt(static_cast<int>(inlined_function_count_)));
372   data->SetOptimizationId(Smi::FromInt(info->optimization_id()));
373 
374   if (info->has_shared_info()) {
375     data->SetSharedFunctionInfo(*info->shared_info());
376   } else {
377     data->SetSharedFunctionInfo(Smi::FromInt(0));
378   }
379 
380   Handle<FixedArray> literals = isolate()->factory()->NewFixedArray(
381       static_cast<int>(deoptimization_literals_.size()), TENURED);
382   {
383     AllowDeferredHandleDereference copy_handles;
384     for (unsigned i = 0; i < deoptimization_literals_.size(); i++) {
385       literals->set(i, *deoptimization_literals_[i]);
386     }
387     data->SetLiteralArray(*literals);
388   }
389 
390   if (info->is_osr()) {
391     DCHECK(osr_pc_offset_ >= 0);
392     data->SetOsrAstId(Smi::FromInt(info_->osr_ast_id().ToInt()));
393     data->SetOsrPcOffset(Smi::FromInt(osr_pc_offset_));
394   } else {
395     BailoutId osr_ast_id = BailoutId::None();
396     data->SetOsrAstId(Smi::FromInt(osr_ast_id.ToInt()));
397     data->SetOsrPcOffset(Smi::FromInt(-1));
398   }
399 
400   // Populate deoptimization entries.
401   for (int i = 0; i < deopt_count; i++) {
402     DeoptimizationState* deoptimization_state = deoptimization_states_[i];
403     data->SetAstId(i, deoptimization_state->bailout_id());
404     CHECK(deoptimization_states_[i]);
405     data->SetTranslationIndex(
406         i, Smi::FromInt(deoptimization_states_[i]->translation_id()));
407     data->SetArgumentsStackHeight(i, Smi::FromInt(0));
408     data->SetPc(i, Smi::FromInt(deoptimization_state->pc_offset()));
409   }
410 
411   code_object->set_deoptimization_data(*data);
412 }
413 
414 
AddJumpTable(Label ** targets,size_t target_count)415 Label* CodeGenerator::AddJumpTable(Label** targets, size_t target_count) {
416   jump_tables_ = new (zone()) JumpTable(jump_tables_, targets, target_count);
417   return jump_tables_->label();
418 }
419 
420 
RecordCallPosition(Instruction * instr)421 void CodeGenerator::RecordCallPosition(Instruction* instr) {
422   CallDescriptor::Flags flags(MiscField::decode(instr->opcode()));
423 
424   bool needs_frame_state = (flags & CallDescriptor::kNeedsFrameState);
425 
426   RecordSafepoint(
427       instr->reference_map(), Safepoint::kSimple, 0,
428       needs_frame_state ? Safepoint::kLazyDeopt : Safepoint::kNoLazyDeopt);
429 
430   if (flags & CallDescriptor::kHasExceptionHandler) {
431     InstructionOperandConverter i(this, instr);
432     bool caught = flags & CallDescriptor::kHasLocalCatchHandler;
433     RpoNumber handler_rpo = i.InputRpo(instr->InputCount() - 1);
434     handlers_.push_back({caught, GetLabel(handler_rpo), masm()->pc_offset()});
435   }
436 
437   if (flags & CallDescriptor::kNeedsNopAfterCall) {
438     AddNopForSmiCodeInlining();
439   }
440 
441   if (needs_frame_state) {
442     MarkLazyDeoptSite();
443     // If the frame state is present, it starts at argument 1 (just after the
444     // code address).
445     size_t frame_state_offset = 1;
446     FrameStateDescriptor* descriptor =
447         GetFrameStateDescriptor(instr, frame_state_offset);
448     int pc_offset = masm()->pc_offset();
449     int deopt_state_id = BuildTranslation(instr, pc_offset, frame_state_offset,
450                                           descriptor->state_combine());
451     // If the pre-call frame state differs from the post-call one, produce the
452     // pre-call frame state, too.
453     // TODO(jarin) We might want to avoid building the pre-call frame state
454     // because it is only used to get locals and arguments (by the debugger and
455     // f.arguments), and those are the same in the pre-call and post-call
456     // states.
457     if (!descriptor->state_combine().IsOutputIgnored()) {
458       deopt_state_id = BuildTranslation(instr, -1, frame_state_offset,
459                                         OutputFrameStateCombine::Ignore());
460     }
461 #if DEBUG
462     // Make sure all the values live in stack slots or they are immediates.
463     // (The values should not live in register because registers are clobbered
464     // by calls.)
465     for (size_t i = 0; i < descriptor->GetSize(); i++) {
466       InstructionOperand* op = instr->InputAt(frame_state_offset + 1 + i);
467       CHECK(op->IsStackSlot() || op->IsDoubleStackSlot() || op->IsImmediate());
468     }
469 #endif
470     safepoints()->RecordLazyDeoptimizationIndex(deopt_state_id);
471   }
472 }
473 
474 
DefineDeoptimizationLiteral(Handle<Object> literal)475 int CodeGenerator::DefineDeoptimizationLiteral(Handle<Object> literal) {
476   int result = static_cast<int>(deoptimization_literals_.size());
477   for (unsigned i = 0; i < deoptimization_literals_.size(); ++i) {
478     if (deoptimization_literals_[i].is_identical_to(literal)) return i;
479   }
480   deoptimization_literals_.push_back(literal);
481   return result;
482 }
483 
484 
GetFrameStateDescriptor(Instruction * instr,size_t frame_state_offset)485 FrameStateDescriptor* CodeGenerator::GetFrameStateDescriptor(
486     Instruction* instr, size_t frame_state_offset) {
487   InstructionOperandConverter i(this, instr);
488   InstructionSequence::StateId state_id =
489       InstructionSequence::StateId::FromInt(i.InputInt32(frame_state_offset));
490   return code()->GetFrameStateDescriptor(state_id);
491 }
492 
493 
TranslateStateValueDescriptor(StateValueDescriptor * desc,Translation * translation,InstructionOperandIterator * iter)494 void CodeGenerator::TranslateStateValueDescriptor(
495     StateValueDescriptor* desc, Translation* translation,
496     InstructionOperandIterator* iter) {
497   if (desc->IsNested()) {
498     translation->BeginCapturedObject(static_cast<int>(desc->size()));
499     for (size_t index = 0; index < desc->fields().size(); index++) {
500       TranslateStateValueDescriptor(&desc->fields()[index], translation, iter);
501     }
502   } else if (desc->IsDuplicate()) {
503     translation->DuplicateObject(static_cast<int>(desc->id()));
504   } else {
505     DCHECK(desc->IsPlain());
506     AddTranslationForOperand(translation, iter->instruction(), iter->Advance(),
507                              desc->type());
508   }
509 }
510 
511 
TranslateFrameStateDescriptorOperands(FrameStateDescriptor * desc,InstructionOperandIterator * iter,OutputFrameStateCombine combine,Translation * translation)512 void CodeGenerator::TranslateFrameStateDescriptorOperands(
513     FrameStateDescriptor* desc, InstructionOperandIterator* iter,
514     OutputFrameStateCombine combine, Translation* translation) {
515   for (size_t index = 0; index < desc->GetSize(combine); index++) {
516     switch (combine.kind()) {
517       case OutputFrameStateCombine::kPushOutput: {
518         DCHECK(combine.GetPushCount() <= iter->instruction()->OutputCount());
519         size_t size_without_output =
520             desc->GetSize(OutputFrameStateCombine::Ignore());
521         // If the index is past the existing stack items in values_.
522         if (index >= size_without_output) {
523           // Materialize the result of the call instruction in this slot.
524           AddTranslationForOperand(
525               translation, iter->instruction(),
526               iter->instruction()->OutputAt(index - size_without_output),
527               MachineType::AnyTagged());
528           continue;
529         }
530         break;
531       }
532       case OutputFrameStateCombine::kPokeAt:
533         // The result of the call should be placed at position
534         // [index_from_top] in the stack (overwriting whatever was
535         // previously there).
536         size_t index_from_top =
537             desc->GetSize(combine) - 1 - combine.GetOffsetToPokeAt();
538         if (index >= index_from_top &&
539             index < index_from_top + iter->instruction()->OutputCount()) {
540           AddTranslationForOperand(
541               translation, iter->instruction(),
542               iter->instruction()->OutputAt(index - index_from_top),
543               MachineType::AnyTagged());
544           iter->Advance();  // We do not use this input, but we need to
545                             // advace, as the input got replaced.
546           continue;
547         }
548         break;
549     }
550     StateValueDescriptor* value_desc = desc->GetStateValueDescriptor();
551     TranslateStateValueDescriptor(&value_desc->fields()[index], translation,
552                                   iter);
553   }
554 }
555 
556 
BuildTranslationForFrameStateDescriptor(FrameStateDescriptor * descriptor,InstructionOperandIterator * iter,Translation * translation,OutputFrameStateCombine state_combine)557 void CodeGenerator::BuildTranslationForFrameStateDescriptor(
558     FrameStateDescriptor* descriptor, InstructionOperandIterator* iter,
559     Translation* translation, OutputFrameStateCombine state_combine) {
560   // Outer-most state must be added to translation first.
561   if (descriptor->outer_state() != nullptr) {
562     BuildTranslationForFrameStateDescriptor(descriptor->outer_state(), iter,
563                                             translation,
564                                             OutputFrameStateCombine::Ignore());
565   }
566 
567   Handle<SharedFunctionInfo> shared_info;
568   if (!descriptor->shared_info().ToHandle(&shared_info)) {
569     if (!info()->has_shared_info()) {
570       return;  // Stub with no SharedFunctionInfo.
571     }
572     shared_info = info()->shared_info();
573   }
574   int shared_info_id = DefineDeoptimizationLiteral(shared_info);
575 
576   switch (descriptor->type()) {
577     case FrameStateType::kJavaScriptFunction:
578       translation->BeginJSFrame(
579           descriptor->bailout_id(), shared_info_id,
580           static_cast<unsigned int>(descriptor->GetSize(state_combine) -
581                                     (1 + descriptor->parameters_count())));
582       break;
583     case FrameStateType::kInterpretedFunction:
584       translation->BeginInterpretedFrame(
585           descriptor->bailout_id(), shared_info_id,
586           static_cast<unsigned int>(descriptor->locals_count()));
587       break;
588     case FrameStateType::kArgumentsAdaptor:
589       translation->BeginArgumentsAdaptorFrame(
590           shared_info_id,
591           static_cast<unsigned int>(descriptor->parameters_count()));
592       break;
593     case FrameStateType::kConstructStub:
594       translation->BeginConstructStubFrame(
595           shared_info_id,
596           static_cast<unsigned int>(descriptor->parameters_count()));
597       break;
598   }
599 
600   TranslateFrameStateDescriptorOperands(descriptor, iter, state_combine,
601                                         translation);
602 }
603 
604 
BuildTranslation(Instruction * instr,int pc_offset,size_t frame_state_offset,OutputFrameStateCombine state_combine)605 int CodeGenerator::BuildTranslation(Instruction* instr, int pc_offset,
606                                     size_t frame_state_offset,
607                                     OutputFrameStateCombine state_combine) {
608   FrameStateDescriptor* descriptor =
609       GetFrameStateDescriptor(instr, frame_state_offset);
610   frame_state_offset++;
611 
612   Translation translation(
613       &translations_, static_cast<int>(descriptor->GetFrameCount()),
614       static_cast<int>(descriptor->GetJSFrameCount()), zone());
615   InstructionOperandIterator iter(instr, frame_state_offset);
616   BuildTranslationForFrameStateDescriptor(descriptor, &iter, &translation,
617                                           state_combine);
618 
619   int deoptimization_id = static_cast<int>(deoptimization_states_.size());
620 
621   deoptimization_states_.push_back(new (zone()) DeoptimizationState(
622       descriptor->bailout_id(), translation.index(), pc_offset));
623 
624   return deoptimization_id;
625 }
626 
627 
AddTranslationForOperand(Translation * translation,Instruction * instr,InstructionOperand * op,MachineType type)628 void CodeGenerator::AddTranslationForOperand(Translation* translation,
629                                              Instruction* instr,
630                                              InstructionOperand* op,
631                                              MachineType type) {
632   if (op->IsStackSlot()) {
633     if (type.representation() == MachineRepresentation::kBit) {
634       translation->StoreBoolStackSlot(LocationOperand::cast(op)->index());
635     } else if (type == MachineType::Int8() || type == MachineType::Int16() ||
636                type == MachineType::Int32()) {
637       translation->StoreInt32StackSlot(LocationOperand::cast(op)->index());
638     } else if (type == MachineType::Uint8() || type == MachineType::Uint16() ||
639                type == MachineType::Uint32()) {
640       translation->StoreUint32StackSlot(LocationOperand::cast(op)->index());
641     } else if (type.representation() == MachineRepresentation::kTagged) {
642       translation->StoreStackSlot(LocationOperand::cast(op)->index());
643     } else {
644       CHECK(false);
645     }
646   } else if (op->IsDoubleStackSlot()) {
647     DCHECK(IsFloatingPoint(type.representation()));
648     translation->StoreDoubleStackSlot(LocationOperand::cast(op)->index());
649   } else if (op->IsRegister()) {
650     InstructionOperandConverter converter(this, instr);
651     if (type.representation() == MachineRepresentation::kBit) {
652       translation->StoreBoolRegister(converter.ToRegister(op));
653     } else if (type == MachineType::Int8() || type == MachineType::Int16() ||
654                type == MachineType::Int32()) {
655       translation->StoreInt32Register(converter.ToRegister(op));
656     } else if (type == MachineType::Uint8() || type == MachineType::Uint16() ||
657                type == MachineType::Uint32()) {
658       translation->StoreUint32Register(converter.ToRegister(op));
659     } else if (type.representation() == MachineRepresentation::kTagged) {
660       translation->StoreRegister(converter.ToRegister(op));
661     } else {
662       CHECK(false);
663     }
664   } else if (op->IsDoubleRegister()) {
665     DCHECK(IsFloatingPoint(type.representation()));
666     InstructionOperandConverter converter(this, instr);
667     translation->StoreDoubleRegister(converter.ToDoubleRegister(op));
668   } else if (op->IsImmediate()) {
669     InstructionOperandConverter converter(this, instr);
670     Constant constant = converter.ToConstant(op);
671     Handle<Object> constant_object;
672     switch (constant.type()) {
673       case Constant::kInt32:
674         DCHECK(type == MachineType::Int32() || type == MachineType::Uint32() ||
675                type.representation() == MachineRepresentation::kBit);
676         constant_object =
677             isolate()->factory()->NewNumberFromInt(constant.ToInt32());
678         break;
679       case Constant::kFloat32:
680         DCHECK(type.representation() == MachineRepresentation::kFloat32 ||
681                type.representation() == MachineRepresentation::kTagged);
682         constant_object = isolate()->factory()->NewNumber(constant.ToFloat32());
683         break;
684       case Constant::kFloat64:
685         DCHECK(type.representation() == MachineRepresentation::kFloat64 ||
686                type.representation() == MachineRepresentation::kTagged);
687         constant_object = isolate()->factory()->NewNumber(constant.ToFloat64());
688         break;
689       case Constant::kHeapObject:
690         DCHECK(type.representation() == MachineRepresentation::kTagged);
691         constant_object = constant.ToHeapObject();
692         break;
693       default:
694         CHECK(false);
695     }
696     if (constant_object.is_identical_to(info()->closure())) {
697       translation->StoreJSFrameFunction();
698     } else {
699       int literal_id = DefineDeoptimizationLiteral(constant_object);
700       translation->StoreLiteral(literal_id);
701     }
702   } else {
703     CHECK(false);
704   }
705 }
706 
707 
MarkLazyDeoptSite()708 void CodeGenerator::MarkLazyDeoptSite() {
709   last_lazy_deopt_pc_ = masm()->pc_offset();
710 }
711 
712 
TailCallFrameStackSlotDelta(int stack_param_delta)713 int CodeGenerator::TailCallFrameStackSlotDelta(int stack_param_delta) {
714   CallDescriptor* descriptor = linkage()->GetIncomingDescriptor();
715   int spill_slots = frame()->GetSpillSlotCount();
716   bool has_frame = descriptor->IsJSFunctionCall() || spill_slots > 0;
717   // Leave the PC on the stack on platforms that have that as part of their ABI
718   int pc_slots = V8_TARGET_ARCH_STORES_RETURN_ADDRESS_ON_STACK ? 1 : 0;
719   int sp_slot_delta =
720       has_frame ? (frame()->GetTotalFrameSlotCount() - pc_slots) : 0;
721   // Discard only slots that won't be used by new parameters.
722   sp_slot_delta += stack_param_delta;
723   return sp_slot_delta;
724 }
725 
726 
OutOfLineCode(CodeGenerator * gen)727 OutOfLineCode::OutOfLineCode(CodeGenerator* gen)
728     : frame_(gen->frame()), masm_(gen->masm()), next_(gen->ools_) {
729   gen->ools_ = this;
730 }
731 
732 
~OutOfLineCode()733 OutOfLineCode::~OutOfLineCode() {}
734 
735 }  // namespace compiler
736 }  // namespace internal
737 }  // namespace v8
738