src/arm64/lithium-codegen-arm64.h

   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 #ifndef V8_ARM64_LITHIUM_CODEGEN_ARM64_H_
   6 #define V8_ARM64_LITHIUM_CODEGEN_ARM64_H_
   7
   8 #include "src/arm64/lithium-arm64.h"
   9
  10 #include "src/arm64/lithium-gap-resolver-arm64.h"
  11 #include "src/deoptimizer.h"
  12 #include "src/lithium-codegen.h"
  13 #include "src/safepoint-table.h"
  14 #include "src/scopes.h"
  15 #include "src/utils.h"
  16
  17 namespace v8 {
  18 namespace internal {
  19
  20 // Forward declarations.
  21 class LDeferredCode;
  22 class SafepointGenerator;
  23 class BranchGenerator;
  24
  25 class LCodeGen: public LCodeGenBase {
  26  public:
  27   LCodeGen(LChunk* chunk, MacroAssembler* assembler, CompilationInfo* info)
  28       : LCodeGenBase(chunk, assembler, info),
  29         deoptimizations_(4, info->zone()),
  30         jump_table_(4, info->zone()),
  31         inlined_function_count_(0),
  32         scope_(info->scope()),
  33         translations_(info->zone()),
  34         deferred_(8, info->zone()),
  35         osr_pc_offset_(-1),
  36         frame_is_built_(false),
  37         safepoints_(info->zone()),
  38         resolver_(this),
  39         expected_safepoint_kind_(Safepoint::kSimple) {
  40     PopulateDeoptimizationLiteralsWithInlinedFunctions();
  41   }
  42
  43   // Simple accessors.
  44   Scope* scope() const { return scope_; }
  45
  46   int LookupDestination(int block_id) const {
  47     return chunk()->LookupDestination(block_id);
  48   }
  49
  50   bool IsNextEmittedBlock(int block_id) const {
  51     return LookupDestination(block_id) == GetNextEmittedBlock();
  52   }
  53
  54   bool NeedsEagerFrame() const {
  55     return GetStackSlotCount() > 0 ||
  56         info()->is_non_deferred_calling() ||
  57         !info()->IsStub() ||
  58         info()->requires_frame();
  59   }
  60   bool NeedsDeferredFrame() const {
  61     return !NeedsEagerFrame() && info()->is_deferred_calling();
  62   }
  63
  64   LinkRegisterStatus GetLinkRegisterState() const {
  65     return frame_is_built_ ? kLRHasBeenSaved : kLRHasNotBeenSaved;
  66   }
  67
  68   // Try to generate code for the entire chunk, but it may fail if the
  69   // chunk contains constructs we cannot handle. Returns true if the
  70   // code generation attempt succeeded.
  71   bool GenerateCode();
  72
  73   // Finish the code by setting stack height, safepoint, and bailout
  74   // information on it.
  75   void FinishCode(Handle<Code> code);
  76
  77   enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
  78   // Support for converting LOperands to assembler types.
  79   Register ToRegister(LOperand* op) const;
  80   Register ToRegister32(LOperand* op) const;
  81   Operand ToOperand(LOperand* op);
  82   Operand ToOperand32(LOperand* op);
  83   MemOperand ToMemOperand(LOperand* op) const;
  84   Handle<Object> ToHandle(LConstantOperand* op) const;
  85
  86   template <class LI>
  87   Operand ToShiftedRightOperand32(LOperand* right, LI* shift_info);
  88
  89   int JSShiftAmountFromLConstant(LOperand* constant) {
  90     return ToInteger32(LConstantOperand::cast(constant)) & 0x1f;
  91   }
  92
  93   // TODO(jbramley): Examine these helpers and check that they make sense.
  94   // IsInteger32Constant returns true for smi constants, for example.
  95   bool IsInteger32Constant(LConstantOperand* op) const;
  96   bool IsSmi(LConstantOperand* op) const;
  97
  98   int32_t ToInteger32(LConstantOperand* op) const;
  99   Smi* ToSmi(LConstantOperand* op) const;
 100   double ToDouble(LConstantOperand* op) const;
 101   DoubleRegister ToDoubleRegister(LOperand* op) const;
 102
 103   // Declare methods that deal with the individual node types.
 104 #define DECLARE_DO(type) void Do##type(L##type* node);
 105   LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
 106 #undef DECLARE_DO
 107
 108  private:
 109   // Return a double scratch register which can be used locally
 110   // when generating code for a lithium instruction.
 111   DoubleRegister double_scratch() { return crankshaft_fp_scratch; }
 112
 113   // Deferred code support.
 114   void DoDeferredNumberTagD(LNumberTagD* instr);
 115   void DoDeferredStackCheck(LStackCheck* instr);
 116   void DoDeferredMaybeGrowElements(LMaybeGrowElements* instr);
 117   void DoDeferredStringCharCodeAt(LStringCharCodeAt* instr);
 118   void DoDeferredStringCharFromCode(LStringCharFromCode* instr);
 119   void DoDeferredMathAbsTagged(LMathAbsTagged* instr,
 120                                Label* exit,
 121                                Label* allocation_entry);
 122
 123   void DoDeferredNumberTagU(LInstruction* instr,
 124                             LOperand* value,
 125                             LOperand* temp1,
 126                             LOperand* temp2);
 127   void DoDeferredTaggedToI(LTaggedToI* instr,
 128                            LOperand* value,
 129                            LOperand* temp1,
 130                            LOperand* temp2);
 131   void DoDeferredAllocate(LAllocate* instr);
 132   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr);
 133   void DoDeferredInstanceMigration(LCheckMaps* instr, Register object);
 134   void DoDeferredLoadMutableDouble(LLoadFieldByIndex* instr,
 135                                    Register result,
 136                                    Register object,
 137                                    Register index);
 138
 139   static Condition TokenToCondition(Token::Value op, bool is_unsigned);
 140   void EmitGoto(int block);
 141   void DoGap(LGap* instr);
 142
 143   // Generic version of EmitBranch. It contains some code to avoid emitting a
 144   // branch on the next emitted basic block where we could just fall-through.
 145   // You shouldn't use that directly but rather consider one of the helper like
 146   // LCodeGen::EmitBranch, LCodeGen::EmitCompareAndBranch...
 147   template<class InstrType>
 148   void EmitBranchGeneric(InstrType instr,
 149                          const BranchGenerator& branch);
 150
 151   template<class InstrType>
 152   void EmitBranch(InstrType instr, Condition condition);
 153
 154   template<class InstrType>
 155   void EmitCompareAndBranch(InstrType instr,
 156                             Condition condition,
 157                             const Register& lhs,
 158                             const Operand& rhs);
 159
 160   template<class InstrType>
 161   void EmitTestAndBranch(InstrType instr,
 162                          Condition condition,
 163                          const Register& value,
 164                          uint64_t mask);
 165
 166   template<class InstrType>
 167   void EmitBranchIfNonZeroNumber(InstrType instr,
 168                                  const FPRegister& value,
 169                                  const FPRegister& scratch);
 170
 171   template<class InstrType>
 172   void EmitBranchIfHeapNumber(InstrType instr,
 173                               const Register& value);
 174
 175   template<class InstrType>
 176   void EmitBranchIfRoot(InstrType instr,
 177                         const Register& value,
 178                         Heap::RootListIndex index);
 179
 180   // Emits optimized code to deep-copy the contents of statically known object
 181   // graphs (e.g. object literal boilerplate). Expects a pointer to the
 182   // allocated destination object in the result register, and a pointer to the
 183   // source object in the source register.
 184   void EmitDeepCopy(Handle<JSObject> object,
 185                     Register result,
 186                     Register source,
 187                     Register scratch,
 188                     int* offset,
 189                     AllocationSiteMode mode);
 190
 191   template <class T>
 192   void EmitVectorLoadICRegisters(T* instr);
 193
 194   // Emits optimized code for %_IsString(x).  Preserves input register.
 195   // Returns the condition on which a final split to
 196   // true and false label should be made, to optimize fallthrough.
 197   Condition EmitIsString(Register input, Register temp1, Label* is_not_string,
 198                          SmiCheck check_needed);
 199
 200   void PopulateDeoptimizationData(Handle<Code> code);
 201   void PopulateDeoptimizationLiteralsWithInlinedFunctions();
 202
 203   MemOperand BuildSeqStringOperand(Register string,
 204                                    Register temp,
 205                                    LOperand* index,
 206                                    String::Encoding encoding);
 207   void DeoptimizeBranch(LInstruction* instr,
 208                         Deoptimizer::DeoptReason deopt_reason,
 209                         BranchType branch_type, Register reg = NoReg,
 210                         int bit = -1,
 211                         Deoptimizer::BailoutType* override_bailout_type = NULL);
 212   void Deoptimize(LInstruction* instr, Deoptimizer::DeoptReason deopt_reason,
 213                   Deoptimizer::BailoutType* override_bailout_type = NULL);
 214   void DeoptimizeIf(Condition cond, LInstruction* instr,
 215                     Deoptimizer::DeoptReason deopt_reason);
 216   void DeoptimizeIfZero(Register rt, LInstruction* instr,
 217                         Deoptimizer::DeoptReason deopt_reason);
 218   void DeoptimizeIfNotZero(Register rt, LInstruction* instr,
 219                            Deoptimizer::DeoptReason deopt_reason);
 220   void DeoptimizeIfNegative(Register rt, LInstruction* instr,
 221                             Deoptimizer::DeoptReason deopt_reason);
 222   void DeoptimizeIfSmi(Register rt, LInstruction* instr,
 223                        Deoptimizer::DeoptReason deopt_reason);
 224   void DeoptimizeIfNotSmi(Register rt, LInstruction* instr,
 225                           Deoptimizer::DeoptReason deopt_reason);
 226   void DeoptimizeIfRoot(Register rt, Heap::RootListIndex index,
 227                         LInstruction* instr,
 228                         Deoptimizer::DeoptReason deopt_reason);
 229   void DeoptimizeIfNotRoot(Register rt, Heap::RootListIndex index,
 230                            LInstruction* instr,
 231                            Deoptimizer::DeoptReason deopt_reason);
 232   void DeoptimizeIfNotHeapNumber(Register object, LInstruction* instr);
 233   void DeoptimizeIfMinusZero(DoubleRegister input, LInstruction* instr,
 234                              Deoptimizer::DeoptReason deopt_reason);
 235   void DeoptimizeIfBitSet(Register rt, int bit, LInstruction* instr,
 236                           Deoptimizer::DeoptReason deopt_reason);
 237   void DeoptimizeIfBitClear(Register rt, int bit, LInstruction* instr,
 238                             Deoptimizer::DeoptReason deopt_reason);
 239
 240   MemOperand PrepareKeyedExternalArrayOperand(Register key,
 241                                               Register base,
 242                                               Register scratch,
 243                                               bool key_is_smi,
 244                                               bool key_is_constant,
 245                                               int constant_key,
 246                                               ElementsKind elements_kind,
 247                                               int base_offset);
 248   MemOperand PrepareKeyedArrayOperand(Register base,
 249                                       Register elements,
 250                                       Register key,
 251                                       bool key_is_tagged,
 252                                       ElementsKind elements_kind,
 253                                       Representation representation,
 254                                       int base_offset);
 255
 256   void RegisterEnvironmentForDeoptimization(LEnvironment* environment,
 257                                             Safepoint::DeoptMode mode);
 258
 259   int GetStackSlotCount() const { return chunk()->spill_slot_count(); }
 260
 261   void AddDeferredCode(LDeferredCode* code) { deferred_.Add(code, zone()); }
 262
 263   // Emit frame translation commands for an environment.
 264   void WriteTranslation(LEnvironment* environment, Translation* translation);
 265
 266   void AddToTranslation(LEnvironment* environment,
 267                         Translation* translation,
 268                         LOperand* op,
 269                         bool is_tagged,
 270                         bool is_uint32,
 271                         int* object_index_pointer,
 272                         int* dematerialized_index_pointer);
 273
 274   void SaveCallerDoubles();
 275   void RestoreCallerDoubles();
 276
 277   // Code generation steps.  Returns true if code generation should continue.
 278   void GenerateBodyInstructionPre(LInstruction* instr) override;
 279   bool GeneratePrologue();
 280   bool GenerateDeferredCode();
 281   bool GenerateJumpTable();
 282   bool GenerateSafepointTable();
 283
 284   // Generates the custom OSR entrypoint and sets the osr_pc_offset.
 285   void GenerateOsrPrologue();
 286
 287   enum SafepointMode {
 288     RECORD_SIMPLE_SAFEPOINT,
 289     RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS
 290   };
 291
 292   void CallCode(Handle<Code> code,
 293                 RelocInfo::Mode mode,
 294                 LInstruction* instr);
 295
 296   void CallCodeGeneric(Handle<Code> code,
 297                        RelocInfo::Mode mode,
 298                        LInstruction* instr,
 299                        SafepointMode safepoint_mode);
 300
 301   void CallRuntime(const Runtime::Function* function,
 302                    int num_arguments,
 303                    LInstruction* instr,
 304                    SaveFPRegsMode save_doubles = kDontSaveFPRegs);
 305
 306   void CallRuntime(Runtime::FunctionId id,
 307                    int num_arguments,
 308                    LInstruction* instr) {
 309     const Runtime::Function* function = Runtime::FunctionForId(id);
 310     CallRuntime(function, num_arguments, instr);
 311   }
 312
 313   void LoadContextFromDeferred(LOperand* context);
 314   void CallRuntimeFromDeferred(Runtime::FunctionId id,
 315                                int argc,
 316                                LInstruction* instr,
 317                                LOperand* context);
 318
 319   // Generate a direct call to a known function.  Expects the function
 320   // to be in x1.
 321   void CallKnownFunction(Handle<JSFunction> function,
 322                          int formal_parameter_count, int arity,
 323                          LInstruction* instr);
 324
 325   // Support for recording safepoint and position information.
 326   void RecordAndWritePosition(int position) override;
 327   void RecordSafepoint(LPointerMap* pointers,
 328                        Safepoint::Kind kind,
 329                        int arguments,
 330                        Safepoint::DeoptMode mode);
 331   void RecordSafepoint(LPointerMap* pointers, Safepoint::DeoptMode mode);
 332   void RecordSafepoint(Safepoint::DeoptMode mode);
 333   void RecordSafepointWithRegisters(LPointerMap* pointers,
 334                                     int arguments,
 335                                     Safepoint::DeoptMode mode);
 336   void RecordSafepointWithLazyDeopt(LInstruction* instr,
 337                                     SafepointMode safepoint_mode);
 338
 339   void EnsureSpaceForLazyDeopt(int space_needed) override;
 340
 341   ZoneList<LEnvironment*> deoptimizations_;
 342   ZoneList<Deoptimizer::JumpTableEntry*> jump_table_;
 343   int inlined_function_count_;
 344   Scope* const scope_;
 345   TranslationBuffer translations_;
 346   ZoneList<LDeferredCode*> deferred_;
 347   int osr_pc_offset_;
 348   bool frame_is_built_;
 349
 350   // Builder that keeps track of safepoints in the code. The table itself is
 351   // emitted at the end of the generated code.
 352   SafepointTableBuilder safepoints_;
 353
 354   // Compiler from a set of parallel moves to a sequential list of moves.
 355   LGapResolver resolver_;
 356
 357   Safepoint::Kind expected_safepoint_kind_;
 358
 359   int old_position_;
 360
 361   class PushSafepointRegistersScope BASE_EMBEDDED {
 362    public:
 363     explicit PushSafepointRegistersScope(LCodeGen* codegen)
 364         : codegen_(codegen) {
 365       DCHECK(codegen_->info()->is_calling());
 366       DCHECK(codegen_->expected_safepoint_kind_ == Safepoint::kSimple);
 367       codegen_->expected_safepoint_kind_ = Safepoint::kWithRegisters;
 368
 369       UseScratchRegisterScope temps(codegen_->masm_);
 370       // Preserve the value of lr which must be saved on the stack (the call to
 371       // the stub will clobber it).
 372       Register to_be_pushed_lr =
 373           temps.UnsafeAcquire(StoreRegistersStateStub::to_be_pushed_lr());
 374       codegen_->masm_->Mov(to_be_pushed_lr, lr);
 375       StoreRegistersStateStub stub(codegen_->isolate());
 376       codegen_->masm_->CallStub(&stub);
 377     }
 378
 379     ~PushSafepointRegistersScope() {
 380       DCHECK(codegen_->expected_safepoint_kind_ == Safepoint::kWithRegisters);
 381       RestoreRegistersStateStub stub(codegen_->isolate());
 382       codegen_->masm_->CallStub(&stub);
 383       codegen_->expected_safepoint_kind_ = Safepoint::kSimple;
 384     }
 385
 386    private:
 387     LCodeGen* codegen_;
 388   };
 389
 390   friend class LDeferredCode;
 391   friend class SafepointGenerator;
 392   DISALLOW_COPY_AND_ASSIGN(LCodeGen);
 393 };
 394
 395
 396 class LDeferredCode: public ZoneObject {
 397  public:
 398   explicit LDeferredCode(LCodeGen* codegen)
 399       : codegen_(codegen),
 400         external_exit_(NULL),
 401         instruction_index_(codegen->current_instruction_) {
 402     codegen->AddDeferredCode(this);
 403   }
 404
 405   virtual ~LDeferredCode() { }
 406   virtual void Generate() = 0;
 407   virtual LInstruction* instr() = 0;
 408
 409   void SetExit(Label* exit) { external_exit_ = exit; }
 410   Label* entry() { return &entry_; }
 411   Label* exit() { return (external_exit_ != NULL) ? external_exit_ : &exit_; }
 412   int instruction_index() const { return instruction_index_; }
 413
 414  protected:
 415   LCodeGen* codegen() const { return codegen_; }
 416   MacroAssembler* masm() const { return codegen_->masm(); }
 417
 418  private:
 419   LCodeGen* codegen_;
 420   Label entry_;
 421   Label exit_;
 422   Label* external_exit_;
 423   int instruction_index_;
 424 };
 425
 426
 427 // This is the abstract class used by EmitBranchGeneric.
 428 // It is used to emit code for conditional branching. The Emit() function
 429 // emits code to branch when the condition holds and EmitInverted() emits
 430 // the branch when the inverted condition is verified.
 431 //
 432 // For actual examples of condition see the concrete implementation in
 433 // lithium-codegen-arm64.cc (e.g. BranchOnCondition, CompareAndBranch).
 434 class BranchGenerator BASE_EMBEDDED {
 435  public:
 436   explicit BranchGenerator(LCodeGen* codegen)
 437     : codegen_(codegen) { }
 438
 439   virtual ~BranchGenerator() { }
 440
 441   virtual void Emit(Label* label) const = 0;
 442   virtual void EmitInverted(Label* label) const = 0;
 443
 444  protected:
 445   MacroAssembler* masm() const { return codegen_->masm(); }
 446
 447   LCodeGen* codegen_;
 448 };
 449
 450 } }  // namespace v8::internal
 451
 452 #endif  // V8_ARM64_LITHIUM_CODEGEN_ARM64_H_