Ben Murdoch | b8a8cc1 | 2014-11-26 15:28:44 +0000 | [diff] [blame^] | 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/compiler/code-generator-impl.h" |
| 8 | #include "src/compiler/linkage.h" |
| 9 | #include "src/compiler/pipeline.h" |
| 10 | |
| 11 | namespace v8 { |
| 12 | namespace internal { |
| 13 | namespace compiler { |
| 14 | |
| 15 | CodeGenerator::CodeGenerator(InstructionSequence* code) |
| 16 | : code_(code), |
| 17 | current_block_(NULL), |
| 18 | current_source_position_(SourcePosition::Invalid()), |
| 19 | masm_(code->zone()->isolate(), NULL, 0), |
| 20 | resolver_(this), |
| 21 | safepoints_(code->zone()), |
| 22 | deoptimization_states_(code->zone()), |
| 23 | deoptimization_literals_(code->zone()), |
| 24 | translations_(code->zone()), |
| 25 | last_lazy_deopt_pc_(0) {} |
| 26 | |
| 27 | |
| 28 | Handle<Code> CodeGenerator::GenerateCode() { |
| 29 | CompilationInfo* info = linkage()->info(); |
| 30 | |
| 31 | // Emit a code line info recording start event. |
| 32 | PositionsRecorder* recorder = masm()->positions_recorder(); |
| 33 | LOG_CODE_EVENT(isolate(), CodeStartLinePosInfoRecordEvent(recorder)); |
| 34 | |
| 35 | // Place function entry hook if requested to do so. |
| 36 | if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) { |
| 37 | ProfileEntryHookStub::MaybeCallEntryHook(masm()); |
| 38 | } |
| 39 | |
| 40 | // Architecture-specific, linkage-specific prologue. |
| 41 | info->set_prologue_offset(masm()->pc_offset()); |
| 42 | AssemblePrologue(); |
| 43 | |
| 44 | // Assemble all instructions. |
| 45 | for (InstructionSequence::const_iterator i = code()->begin(); |
| 46 | i != code()->end(); ++i) { |
| 47 | AssembleInstruction(*i); |
| 48 | } |
| 49 | |
| 50 | FinishCode(masm()); |
| 51 | |
| 52 | // Ensure there is space for lazy deopt. |
| 53 | if (!info->IsStub()) { |
| 54 | int target_offset = masm()->pc_offset() + Deoptimizer::patch_size(); |
| 55 | while (masm()->pc_offset() < target_offset) { |
| 56 | masm()->nop(); |
| 57 | } |
| 58 | } |
| 59 | |
| 60 | safepoints()->Emit(masm(), frame()->GetSpillSlotCount()); |
| 61 | |
| 62 | // TODO(titzer): what are the right code flags here? |
| 63 | Code::Kind kind = Code::STUB; |
| 64 | if (linkage()->GetIncomingDescriptor()->IsJSFunctionCall()) { |
| 65 | kind = Code::OPTIMIZED_FUNCTION; |
| 66 | } |
| 67 | Handle<Code> result = v8::internal::CodeGenerator::MakeCodeEpilogue( |
| 68 | masm(), Code::ComputeFlags(kind), info); |
| 69 | result->set_is_turbofanned(true); |
| 70 | result->set_stack_slots(frame()->GetSpillSlotCount()); |
| 71 | result->set_safepoint_table_offset(safepoints()->GetCodeOffset()); |
| 72 | |
| 73 | PopulateDeoptimizationData(result); |
| 74 | |
| 75 | // Emit a code line info recording stop event. |
| 76 | void* line_info = recorder->DetachJITHandlerData(); |
| 77 | LOG_CODE_EVENT(isolate(), CodeEndLinePosInfoRecordEvent(*result, line_info)); |
| 78 | |
| 79 | return result; |
| 80 | } |
| 81 | |
| 82 | |
| 83 | void CodeGenerator::RecordSafepoint(PointerMap* pointers, Safepoint::Kind kind, |
| 84 | int arguments, |
| 85 | Safepoint::DeoptMode deopt_mode) { |
| 86 | const ZoneList<InstructionOperand*>* operands = |
| 87 | pointers->GetNormalizedOperands(); |
| 88 | Safepoint safepoint = |
| 89 | safepoints()->DefineSafepoint(masm(), kind, arguments, deopt_mode); |
| 90 | for (int i = 0; i < operands->length(); i++) { |
| 91 | InstructionOperand* pointer = operands->at(i); |
| 92 | if (pointer->IsStackSlot()) { |
| 93 | safepoint.DefinePointerSlot(pointer->index(), zone()); |
| 94 | } else if (pointer->IsRegister() && (kind & Safepoint::kWithRegisters)) { |
| 95 | Register reg = Register::FromAllocationIndex(pointer->index()); |
| 96 | safepoint.DefinePointerRegister(reg, zone()); |
| 97 | } |
| 98 | } |
| 99 | } |
| 100 | |
| 101 | |
| 102 | void CodeGenerator::AssembleInstruction(Instruction* instr) { |
| 103 | if (instr->IsBlockStart()) { |
| 104 | // Bind a label for a block start and handle parallel moves. |
| 105 | BlockStartInstruction* block_start = BlockStartInstruction::cast(instr); |
| 106 | current_block_ = block_start->block(); |
| 107 | if (FLAG_code_comments) { |
| 108 | // TODO(titzer): these code comments are a giant memory leak. |
| 109 | Vector<char> buffer = Vector<char>::New(32); |
| 110 | SNPrintF(buffer, "-- B%d start --", block_start->block()->id()); |
| 111 | masm()->RecordComment(buffer.start()); |
| 112 | } |
| 113 | masm()->bind(block_start->label()); |
| 114 | } |
| 115 | if (instr->IsGapMoves()) { |
| 116 | // Handle parallel moves associated with the gap instruction. |
| 117 | AssembleGap(GapInstruction::cast(instr)); |
| 118 | } else if (instr->IsSourcePosition()) { |
| 119 | AssembleSourcePosition(SourcePositionInstruction::cast(instr)); |
| 120 | } else { |
| 121 | // Assemble architecture-specific code for the instruction. |
| 122 | AssembleArchInstruction(instr); |
| 123 | |
| 124 | // Assemble branches or boolean materializations after this instruction. |
| 125 | FlagsMode mode = FlagsModeField::decode(instr->opcode()); |
| 126 | FlagsCondition condition = FlagsConditionField::decode(instr->opcode()); |
| 127 | switch (mode) { |
| 128 | case kFlags_none: |
| 129 | return; |
| 130 | case kFlags_set: |
| 131 | return AssembleArchBoolean(instr, condition); |
| 132 | case kFlags_branch: |
| 133 | return AssembleArchBranch(instr, condition); |
| 134 | } |
| 135 | UNREACHABLE(); |
| 136 | } |
| 137 | } |
| 138 | |
| 139 | |
| 140 | void CodeGenerator::AssembleSourcePosition(SourcePositionInstruction* instr) { |
| 141 | SourcePosition source_position = instr->source_position(); |
| 142 | if (source_position == current_source_position_) return; |
| 143 | DCHECK(!source_position.IsInvalid()); |
| 144 | if (!source_position.IsUnknown()) { |
| 145 | int code_pos = source_position.raw(); |
| 146 | masm()->positions_recorder()->RecordPosition(source_position.raw()); |
| 147 | masm()->positions_recorder()->WriteRecordedPositions(); |
| 148 | if (FLAG_code_comments) { |
| 149 | Vector<char> buffer = Vector<char>::New(256); |
| 150 | CompilationInfo* info = linkage()->info(); |
| 151 | int ln = Script::GetLineNumber(info->script(), code_pos); |
| 152 | int cn = Script::GetColumnNumber(info->script(), code_pos); |
| 153 | if (info->script()->name()->IsString()) { |
| 154 | Handle<String> file(String::cast(info->script()->name())); |
| 155 | base::OS::SNPrintF(buffer.start(), buffer.length(), "-- %s:%d:%d --", |
| 156 | file->ToCString().get(), ln, cn); |
| 157 | } else { |
| 158 | base::OS::SNPrintF(buffer.start(), buffer.length(), |
| 159 | "-- <unknown>:%d:%d --", ln, cn); |
| 160 | } |
| 161 | masm()->RecordComment(buffer.start()); |
| 162 | } |
| 163 | } |
| 164 | current_source_position_ = source_position; |
| 165 | } |
| 166 | |
| 167 | |
| 168 | void CodeGenerator::AssembleGap(GapInstruction* instr) { |
| 169 | for (int i = GapInstruction::FIRST_INNER_POSITION; |
| 170 | i <= GapInstruction::LAST_INNER_POSITION; i++) { |
| 171 | GapInstruction::InnerPosition inner_pos = |
| 172 | static_cast<GapInstruction::InnerPosition>(i); |
| 173 | ParallelMove* move = instr->GetParallelMove(inner_pos); |
| 174 | if (move != NULL) resolver()->Resolve(move); |
| 175 | } |
| 176 | } |
| 177 | |
| 178 | |
| 179 | void CodeGenerator::PopulateDeoptimizationData(Handle<Code> code_object) { |
| 180 | CompilationInfo* info = linkage()->info(); |
| 181 | int deopt_count = static_cast<int>(deoptimization_states_.size()); |
| 182 | if (deopt_count == 0) return; |
| 183 | Handle<DeoptimizationInputData> data = |
| 184 | DeoptimizationInputData::New(isolate(), deopt_count, TENURED); |
| 185 | |
| 186 | Handle<ByteArray> translation_array = |
| 187 | translations_.CreateByteArray(isolate()->factory()); |
| 188 | |
| 189 | data->SetTranslationByteArray(*translation_array); |
| 190 | data->SetInlinedFunctionCount(Smi::FromInt(0)); |
| 191 | data->SetOptimizationId(Smi::FromInt(info->optimization_id())); |
| 192 | // TODO(jarin) The following code was copied over from Lithium, not sure |
| 193 | // whether the scope or the IsOptimizing condition are really needed. |
| 194 | if (info->IsOptimizing()) { |
| 195 | // Reference to shared function info does not change between phases. |
| 196 | AllowDeferredHandleDereference allow_handle_dereference; |
| 197 | data->SetSharedFunctionInfo(*info->shared_info()); |
| 198 | } else { |
| 199 | data->SetSharedFunctionInfo(Smi::FromInt(0)); |
| 200 | } |
| 201 | |
| 202 | Handle<FixedArray> literals = isolate()->factory()->NewFixedArray( |
| 203 | static_cast<int>(deoptimization_literals_.size()), TENURED); |
| 204 | { |
| 205 | AllowDeferredHandleDereference copy_handles; |
| 206 | for (unsigned i = 0; i < deoptimization_literals_.size(); i++) { |
| 207 | literals->set(i, *deoptimization_literals_[i]); |
| 208 | } |
| 209 | data->SetLiteralArray(*literals); |
| 210 | } |
| 211 | |
| 212 | // No OSR in Turbofan yet... |
| 213 | BailoutId osr_ast_id = BailoutId::None(); |
| 214 | data->SetOsrAstId(Smi::FromInt(osr_ast_id.ToInt())); |
| 215 | data->SetOsrPcOffset(Smi::FromInt(-1)); |
| 216 | |
| 217 | // Populate deoptimization entries. |
| 218 | for (int i = 0; i < deopt_count; i++) { |
| 219 | DeoptimizationState* deoptimization_state = deoptimization_states_[i]; |
| 220 | data->SetAstId(i, deoptimization_state->bailout_id()); |
| 221 | CHECK_NE(NULL, deoptimization_states_[i]); |
| 222 | data->SetTranslationIndex( |
| 223 | i, Smi::FromInt(deoptimization_states_[i]->translation_id())); |
| 224 | data->SetArgumentsStackHeight(i, Smi::FromInt(0)); |
| 225 | data->SetPc(i, Smi::FromInt(deoptimization_state->pc_offset())); |
| 226 | } |
| 227 | |
| 228 | code_object->set_deoptimization_data(*data); |
| 229 | } |
| 230 | |
| 231 | |
| 232 | void CodeGenerator::AddSafepointAndDeopt(Instruction* instr) { |
| 233 | CallDescriptor::Flags flags(MiscField::decode(instr->opcode())); |
| 234 | |
| 235 | bool needs_frame_state = (flags & CallDescriptor::kNeedsFrameState); |
| 236 | |
| 237 | RecordSafepoint( |
| 238 | instr->pointer_map(), Safepoint::kSimple, 0, |
| 239 | needs_frame_state ? Safepoint::kLazyDeopt : Safepoint::kNoLazyDeopt); |
| 240 | |
| 241 | if (flags & CallDescriptor::kNeedsNopAfterCall) { |
| 242 | AddNopForSmiCodeInlining(); |
| 243 | } |
| 244 | |
| 245 | if (needs_frame_state) { |
| 246 | MarkLazyDeoptSite(); |
| 247 | // If the frame state is present, it starts at argument 1 |
| 248 | // (just after the code address). |
| 249 | InstructionOperandConverter converter(this, instr); |
| 250 | // Deoptimization info starts at argument 1 |
| 251 | size_t frame_state_offset = 1; |
| 252 | FrameStateDescriptor* descriptor = |
| 253 | GetFrameStateDescriptor(instr, frame_state_offset); |
| 254 | int pc_offset = masm()->pc_offset(); |
| 255 | int deopt_state_id = BuildTranslation(instr, pc_offset, frame_state_offset, |
| 256 | descriptor->state_combine()); |
| 257 | // If the pre-call frame state differs from the post-call one, produce the |
| 258 | // pre-call frame state, too. |
| 259 | // TODO(jarin) We might want to avoid building the pre-call frame state |
| 260 | // because it is only used to get locals and arguments (by the debugger and |
| 261 | // f.arguments), and those are the same in the pre-call and post-call |
| 262 | // states. |
| 263 | if (descriptor->state_combine() != kIgnoreOutput) { |
| 264 | deopt_state_id = |
| 265 | BuildTranslation(instr, -1, frame_state_offset, kIgnoreOutput); |
| 266 | } |
| 267 | #if DEBUG |
| 268 | // Make sure all the values live in stack slots or they are immediates. |
| 269 | // (The values should not live in register because registers are clobbered |
| 270 | // by calls.) |
| 271 | for (size_t i = 0; i < descriptor->size(); i++) { |
| 272 | InstructionOperand* op = instr->InputAt(frame_state_offset + 1 + i); |
| 273 | CHECK(op->IsStackSlot() || op->IsImmediate()); |
| 274 | } |
| 275 | #endif |
| 276 | safepoints()->RecordLazyDeoptimizationIndex(deopt_state_id); |
| 277 | } |
| 278 | } |
| 279 | |
| 280 | |
| 281 | int CodeGenerator::DefineDeoptimizationLiteral(Handle<Object> literal) { |
| 282 | int result = static_cast<int>(deoptimization_literals_.size()); |
| 283 | for (unsigned i = 0; i < deoptimization_literals_.size(); ++i) { |
| 284 | if (deoptimization_literals_[i].is_identical_to(literal)) return i; |
| 285 | } |
| 286 | deoptimization_literals_.push_back(literal); |
| 287 | return result; |
| 288 | } |
| 289 | |
| 290 | |
| 291 | FrameStateDescriptor* CodeGenerator::GetFrameStateDescriptor( |
| 292 | Instruction* instr, size_t frame_state_offset) { |
| 293 | InstructionOperandConverter i(this, instr); |
| 294 | InstructionSequence::StateId state_id = InstructionSequence::StateId::FromInt( |
| 295 | i.InputInt32(static_cast<int>(frame_state_offset))); |
| 296 | return code()->GetFrameStateDescriptor(state_id); |
| 297 | } |
| 298 | |
| 299 | |
| 300 | void CodeGenerator::BuildTranslationForFrameStateDescriptor( |
| 301 | FrameStateDescriptor* descriptor, Instruction* instr, |
| 302 | Translation* translation, size_t frame_state_offset, |
| 303 | OutputFrameStateCombine state_combine) { |
| 304 | // Outer-most state must be added to translation first. |
| 305 | if (descriptor->outer_state() != NULL) { |
| 306 | BuildTranslationForFrameStateDescriptor(descriptor->outer_state(), instr, |
| 307 | translation, frame_state_offset, |
| 308 | kIgnoreOutput); |
| 309 | } |
| 310 | |
| 311 | int id = Translation::kSelfLiteralId; |
| 312 | if (!descriptor->jsfunction().is_null()) { |
| 313 | id = DefineDeoptimizationLiteral( |
| 314 | Handle<Object>::cast(descriptor->jsfunction().ToHandleChecked())); |
| 315 | } |
| 316 | |
| 317 | switch (descriptor->type()) { |
| 318 | case JS_FRAME: |
| 319 | translation->BeginJSFrame( |
| 320 | descriptor->bailout_id(), id, |
| 321 | static_cast<unsigned int>(descriptor->GetHeight(state_combine))); |
| 322 | break; |
| 323 | case ARGUMENTS_ADAPTOR: |
| 324 | translation->BeginArgumentsAdaptorFrame( |
| 325 | id, static_cast<unsigned int>(descriptor->parameters_count())); |
| 326 | break; |
| 327 | } |
| 328 | |
| 329 | frame_state_offset += descriptor->outer_state()->GetTotalSize(); |
| 330 | for (size_t i = 0; i < descriptor->size(); i++) { |
| 331 | AddTranslationForOperand( |
| 332 | translation, instr, |
| 333 | instr->InputAt(static_cast<int>(frame_state_offset + i))); |
| 334 | } |
| 335 | |
| 336 | switch (state_combine) { |
| 337 | case kPushOutput: |
| 338 | DCHECK(instr->OutputCount() == 1); |
| 339 | AddTranslationForOperand(translation, instr, instr->OutputAt(0)); |
| 340 | break; |
| 341 | case kIgnoreOutput: |
| 342 | break; |
| 343 | } |
| 344 | } |
| 345 | |
| 346 | |
| 347 | int CodeGenerator::BuildTranslation(Instruction* instr, int pc_offset, |
| 348 | size_t frame_state_offset, |
| 349 | OutputFrameStateCombine state_combine) { |
| 350 | FrameStateDescriptor* descriptor = |
| 351 | GetFrameStateDescriptor(instr, frame_state_offset); |
| 352 | frame_state_offset++; |
| 353 | |
| 354 | Translation translation( |
| 355 | &translations_, static_cast<int>(descriptor->GetFrameCount()), |
| 356 | static_cast<int>(descriptor->GetJSFrameCount()), zone()); |
| 357 | BuildTranslationForFrameStateDescriptor(descriptor, instr, &translation, |
| 358 | frame_state_offset, state_combine); |
| 359 | |
| 360 | int deoptimization_id = static_cast<int>(deoptimization_states_.size()); |
| 361 | |
| 362 | deoptimization_states_.push_back(new (zone()) DeoptimizationState( |
| 363 | descriptor->bailout_id(), translation.index(), pc_offset)); |
| 364 | |
| 365 | return deoptimization_id; |
| 366 | } |
| 367 | |
| 368 | |
| 369 | void CodeGenerator::AddTranslationForOperand(Translation* translation, |
| 370 | Instruction* instr, |
| 371 | InstructionOperand* op) { |
| 372 | if (op->IsStackSlot()) { |
| 373 | translation->StoreStackSlot(op->index()); |
| 374 | } else if (op->IsDoubleStackSlot()) { |
| 375 | translation->StoreDoubleStackSlot(op->index()); |
| 376 | } else if (op->IsRegister()) { |
| 377 | InstructionOperandConverter converter(this, instr); |
| 378 | translation->StoreRegister(converter.ToRegister(op)); |
| 379 | } else if (op->IsDoubleRegister()) { |
| 380 | InstructionOperandConverter converter(this, instr); |
| 381 | translation->StoreDoubleRegister(converter.ToDoubleRegister(op)); |
| 382 | } else if (op->IsImmediate()) { |
| 383 | InstructionOperandConverter converter(this, instr); |
| 384 | Constant constant = converter.ToConstant(op); |
| 385 | Handle<Object> constant_object; |
| 386 | switch (constant.type()) { |
| 387 | case Constant::kInt32: |
| 388 | constant_object = |
| 389 | isolate()->factory()->NewNumberFromInt(constant.ToInt32()); |
| 390 | break; |
| 391 | case Constant::kFloat64: |
| 392 | constant_object = isolate()->factory()->NewNumber(constant.ToFloat64()); |
| 393 | break; |
| 394 | case Constant::kHeapObject: |
| 395 | constant_object = constant.ToHeapObject(); |
| 396 | break; |
| 397 | default: |
| 398 | UNREACHABLE(); |
| 399 | } |
| 400 | int literal_id = DefineDeoptimizationLiteral(constant_object); |
| 401 | translation->StoreLiteral(literal_id); |
| 402 | } else { |
| 403 | UNREACHABLE(); |
| 404 | } |
| 405 | } |
| 406 | |
| 407 | |
| 408 | void CodeGenerator::MarkLazyDeoptSite() { |
| 409 | last_lazy_deopt_pc_ = masm()->pc_offset(); |
| 410 | } |
| 411 | |
| 412 | #if !V8_TURBOFAN_BACKEND |
| 413 | |
| 414 | void CodeGenerator::AssembleArchInstruction(Instruction* instr) { |
| 415 | UNIMPLEMENTED(); |
| 416 | } |
| 417 | |
| 418 | |
| 419 | void CodeGenerator::AssembleArchBranch(Instruction* instr, |
| 420 | FlagsCondition condition) { |
| 421 | UNIMPLEMENTED(); |
| 422 | } |
| 423 | |
| 424 | |
| 425 | void CodeGenerator::AssembleArchBoolean(Instruction* instr, |
| 426 | FlagsCondition condition) { |
| 427 | UNIMPLEMENTED(); |
| 428 | } |
| 429 | |
| 430 | |
| 431 | void CodeGenerator::AssembleDeoptimizerCall(int deoptimization_id) { |
| 432 | UNIMPLEMENTED(); |
| 433 | } |
| 434 | |
| 435 | |
| 436 | void CodeGenerator::AssemblePrologue() { UNIMPLEMENTED(); } |
| 437 | |
| 438 | |
| 439 | void CodeGenerator::AssembleReturn() { UNIMPLEMENTED(); } |
| 440 | |
| 441 | |
| 442 | void CodeGenerator::AssembleMove(InstructionOperand* source, |
| 443 | InstructionOperand* destination) { |
| 444 | UNIMPLEMENTED(); |
| 445 | } |
| 446 | |
| 447 | |
| 448 | void CodeGenerator::AssembleSwap(InstructionOperand* source, |
| 449 | InstructionOperand* destination) { |
| 450 | UNIMPLEMENTED(); |
| 451 | } |
| 452 | |
| 453 | |
| 454 | void CodeGenerator::AddNopForSmiCodeInlining() { UNIMPLEMENTED(); } |
| 455 | |
| 456 | #endif // !V8_TURBOFAN_BACKEND |
| 457 | |
| 458 | } // namespace compiler |
| 459 | } // namespace internal |
| 460 | } // namespace v8 |