Land the Fan (disabled)

src/compiler/code-generator.cc

+// Copyright 2013 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "src/compiler/code-generator.h"
+
+#include "src/compiler/code-generator-impl.h"
+#include "src/compiler/linkage.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+CodeGenerator::CodeGenerator(InstructionSequence* code)
+    : code_(code),
+      current_block_(NULL),
+      current_source_position_(SourcePosition::Invalid()),
+      masm_(code->zone()->isolate(), NULL, 0),
+      resolver_(this),
+      safepoints_(code->zone()),
+      lazy_deoptimization_entries_(
+          LazyDeoptimizationEntries::allocator_type(code->zone())),
+      deoptimization_states_(
+          DeoptimizationStates::allocator_type(code->zone())),
+      deoptimization_literals_(Literals::allocator_type(code->zone())),
+      translations_(code->zone()) {
+  deoptimization_states_.resize(code->GetDeoptimizationEntryCount(), NULL);
+}
+
+
+Handle<Code> CodeGenerator::GenerateCode() {
+  CompilationInfo* info = linkage()->info();
+
+  // Emit a code line info recording start event.
+  PositionsRecorder* recorder = masm()->positions_recorder();
+  LOG_CODE_EVENT(isolate(), CodeStartLinePosInfoRecordEvent(recorder));
+
+  // Place function entry hook if requested to do so.
+  if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) {
+    ProfileEntryHookStub::MaybeCallEntryHook(masm());
+  }
+
+  // Architecture-specific, linkage-specific prologue.
+  info->set_prologue_offset(masm()->pc_offset());
+  AssemblePrologue();
+
+  // Assemble all instructions.
+  for (InstructionSequence::const_iterator i = code()->begin();
+       i != code()->end(); ++i) {
+    AssembleInstruction(*i);
+  }
+
+  FinishCode(masm());
+
+  safepoints()->Emit(masm(), frame()->GetSpillSlotCount());
+
+  // TODO(titzer): what are the right code flags here?
+  Code::Kind kind = Code::STUB;
+  if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) {
+    kind = Code::OPTIMIZED_FUNCTION;
+  }
+  Handle<Code> result = v8::internal::CodeGenerator::MakeCodeEpilogue(
+      masm(), Code::ComputeFlags(kind), info);
+  result->set_is_turbofanned(true);
+  result->set_stack_slots(frame()->GetSpillSlotCount());
+  result->set_safepoint_table_offset(safepoints()->GetCodeOffset());
+
+  PopulateDeoptimizationData(result);
+
+  // Emit a code line info recording stop event.
+  void* line_info = recorder->DetachJITHandlerData();
+  LOG_CODE_EVENT(isolate(), CodeEndLinePosInfoRecordEvent(*result, line_info));
+
+  return result;
+}
+
+
+void CodeGenerator::RecordSafepoint(PointerMap* pointers, Safepoint::Kind kind,
+                                    int arguments,
+                                    Safepoint::DeoptMode deopt_mode) {
+  const ZoneList<InstructionOperand*>* operands =
+      pointers->GetNormalizedOperands();
+  Safepoint safepoint =
+      safepoints()->DefineSafepoint(masm(), kind, arguments, deopt_mode);
+  for (int i = 0; i < operands->length(); i++) {
+    InstructionOperand* pointer = operands->at(i);
+    if (pointer->IsStackSlot()) {
+      safepoint.DefinePointerSlot(pointer->index(), zone());
+    } else if (pointer->IsRegister() && (kind & Safepoint::kWithRegisters)) {
+      Register reg = Register::FromAllocationIndex(pointer->index());
+      safepoint.DefinePointerRegister(reg, zone());
+    }
+  }
+}
+
+
+void CodeGenerator::AssembleInstruction(Instruction* instr) {
+  if (instr->IsBlockStart()) {
+    // Bind a label for a block start and handle parallel moves.
+    BlockStartInstruction* block_start = BlockStartInstruction::cast(instr);
+    current_block_ = block_start->block();
+    if (FLAG_code_comments) {
+      // TODO(titzer): these code comments are a giant memory leak.
+      Vector<char> buffer = Vector<char>::New(32);
+      SNPrintF(buffer, "-- B%d start --", block_start->block()->id());
+      masm()->RecordComment(buffer.start());
+    }
+    masm()->bind(block_start->label());
+  }
+  if (instr->IsGapMoves()) {
+    // Handle parallel moves associated with the gap instruction.
+    AssembleGap(GapInstruction::cast(instr));
+  } else if (instr->IsSourcePosition()) {
+    AssembleSourcePosition(SourcePositionInstruction::cast(instr));
+  } else {
+    // Assemble architecture-specific code for the instruction.
+    AssembleArchInstruction(instr);
+
+    // Assemble branches or boolean materializations after this instruction.
+    FlagsMode mode = FlagsModeField::decode(instr->opcode());
+    FlagsCondition condition = FlagsConditionField::decode(instr->opcode());
+    switch (mode) {
+      case kFlags_none:
+        return;
+      case kFlags_set:
+        return AssembleArchBoolean(instr, condition);
+      case kFlags_branch:
+        return AssembleArchBranch(instr, condition);
+    }
+    UNREACHABLE();
+  }
+}
+
+
+void CodeGenerator::AssembleSourcePosition(SourcePositionInstruction* instr) {
+  SourcePosition source_position = instr->source_position();
+  if (source_position == current_source_position_) return;
+  ASSERT(!source_position.IsInvalid());
+  if (!source_position.IsUnknown()) {
+    int code_pos = source_position.raw();
+    masm()->positions_recorder()->RecordPosition(source_position.raw());
+    masm()->positions_recorder()->WriteRecordedPositions();
+    if (FLAG_code_comments) {
+      Vector<char> buffer = Vector<char>::New(256);
+      CompilationInfo* info = linkage()->info();
+      int ln = Script::GetLineNumber(info->script(), code_pos);
+      int cn = Script::GetColumnNumber(info->script(), code_pos);
+      if (info->script()->name()->IsString()) {
+        Handle<String> file(String::cast(info->script()->name()));
+        base::OS::SNPrintF(buffer.start(), buffer.length(), "-- %s:%d:%d --",
+                           file->ToCString().get(), ln, cn);
+      } else {
+        base::OS::SNPrintF(buffer.start(), buffer.length(),
+                           "-- <unknown>:%d:%d --", ln, cn);
+      }
+      masm()->RecordComment(buffer.start());
+    }
+  }
+  current_source_position_ = source_position;
+}
+
+
+void CodeGenerator::AssembleGap(GapInstruction* instr) {
+  for (int i = GapInstruction::FIRST_INNER_POSITION;
+       i <= GapInstruction::LAST_INNER_POSITION; i++) {
+    GapInstruction::InnerPosition inner_pos =
+        static_cast<GapInstruction::InnerPosition>(i);
+    ParallelMove* move = instr->GetParallelMove(inner_pos);
+    if (move != NULL) resolver()->Resolve(move);
+  }
+}
+
+
+void CodeGenerator::PopulateDeoptimizationData(Handle<Code> code_object) {
+  CompilationInfo* info = linkage()->info();
+  int deopt_count = code()->GetDeoptimizationEntryCount();
+  int patch_count = lazy_deoptimization_entries_.size();
+  if (patch_count == 0 && deopt_count == 0) return;
+  Handle<DeoptimizationInputData> data = DeoptimizationInputData::New(
+      isolate(), deopt_count, patch_count, TENURED);
+
+  Handle<ByteArray> translation_array =
+      translations_.CreateByteArray(isolate()->factory());
+
+  data->SetTranslationByteArray(*translation_array);
+  data->SetInlinedFunctionCount(Smi::FromInt(0));
+  data->SetOptimizationId(Smi::FromInt(info->optimization_id()));
+  // TODO(jarin) The following code was copied over from Lithium, not sure
+  // whether the scope or the IsOptimizing condition are really needed.
+  if (info->IsOptimizing()) {
+    // Reference to shared function info does not change between phases.
+    AllowDeferredHandleDereference allow_handle_dereference;
+    data->SetSharedFunctionInfo(*info->shared_info());
+  } else {
+    data->SetSharedFunctionInfo(Smi::FromInt(0));
+  }
+
+  Handle<FixedArray> literals = isolate()->factory()->NewFixedArray(
+      deoptimization_literals_.size(), TENURED);
+  {
+    AllowDeferredHandleDereference copy_handles;
+    for (unsigned i = 0; i < deoptimization_literals_.size(); i++) {
+      literals->set(i, *deoptimization_literals_[i]);
+    }
+    data->SetLiteralArray(*literals);
+  }
+
+  // No OSR in Turbofan yet...
+  BailoutId osr_ast_id = BailoutId::None();
+  data->SetOsrAstId(Smi::FromInt(osr_ast_id.ToInt()));
+  data->SetOsrPcOffset(Smi::FromInt(-1));
+
+  // Populate deoptimization entries.
+  for (int i = 0; i < deopt_count; i++) {
+    FrameStateDescriptor descriptor = code()->GetDeoptimizationEntry(i);
+    data->SetAstId(i, descriptor.bailout_id());
+    data->SetTranslationIndex(i, Smi::FromInt(0));
+    data->SetArgumentsStackHeight(i, Smi::FromInt(0));
+    data->SetPc(i, Smi::FromInt(-1));
+  }
+
+  // Populate the return address patcher entries.
+  for (int i = 0; i < patch_count; ++i) {
+    LazyDeoptimizationEntry entry = lazy_deoptimization_entries_[i];
+    ASSERT(entry.position_after_call() == entry.continuation()->pos() ||
+           IsNopForSmiCodeInlining(code_object, entry.position_after_call(),
+                                   entry.continuation()->pos()));
+    data->SetReturnAddressPc(i, Smi::FromInt(entry.position_after_call()));
+    data->SetPatchedAddressPc(i, Smi::FromInt(entry.deoptimization()->pos()));
+  }
+
+  code_object->set_deoptimization_data(*data);
+}
+
+
+void CodeGenerator::RecordLazyDeoptimizationEntry(Instruction* instr) {
+  InstructionOperandConverter i(this, instr);
+
+  Label after_call;
+  masm()->bind(&after_call);
+
+  // The continuation and deoptimization are the last two inputs:
+  BasicBlock* cont_block = i.InputBlock(instr->InputCount() - 2);
+  BasicBlock* deopt_block = i.InputBlock(instr->InputCount() - 1);
+
+  Label* cont_label = code_->GetLabel(cont_block);
+  Label* deopt_label = code_->GetLabel(deopt_block);
+
+  lazy_deoptimization_entries_.push_back(
+      LazyDeoptimizationEntry(after_call.pos(), cont_label, deopt_label));
+}
+
+
+int CodeGenerator::DefineDeoptimizationLiteral(Handle<Object> literal) {
+  int result = deoptimization_literals_.size();
+  for (unsigned i = 0; i < deoptimization_literals_.size(); ++i) {
+    if (deoptimization_literals_[i].is_identical_to(literal)) return i;
+  }
+  deoptimization_literals_.push_back(literal);
+  return result;
+}
+
+
+void CodeGenerator::BuildTranslation(Instruction* instr,
+                                     int deoptimization_id) {
+  // We should build translation only once.
+  ASSERT_EQ(NULL, deoptimization_states_[deoptimization_id]);
+
+  // TODO(jarin) This should build translation codes from the instruction inputs
+  // and from the framestate descriptor. At the moment, we only create a dummy
+  // translation.
+
+  FrameStateDescriptor descriptor =
+      code()->GetDeoptimizationEntry(deoptimization_id);
+  Translation translation(&translations_, 1, 1, zone());
+  translation.BeginJSFrame(descriptor.bailout_id(), Translation::kSelfLiteralId,
+                           0);
+  int undefined_literal_id =
+      DefineDeoptimizationLiteral(isolate()->factory()->undefined_value());
+  translation.StoreLiteral(undefined_literal_id);
+
+  deoptimization_states_[deoptimization_id] =
+      new (zone()) DeoptimizationState(translation.index());
+}
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8