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         deoptimization_literals_(8, info->zone()),
  32         inlined_function_count_(0),
  33         scope_(info->scope()),
  34         translations_(info->zone()),
  35         deferred_(8, info->zone()),
  36         osr_pc_offset_(-1),
  37         frame_is_built_(false),
  38         safepoints_(info->zone()),
  39         resolver_(this),
  40         expected_safepoint_kind_(Safepoint::kSimple) {
  41     PopulateDeoptimizationLiteralsWithInlinedFunctions();
  42   }
  43
  44   // Simple accessors.
  45   Scope* scope() const { return scope_; }
  46
  47   int LookupDestination(int block_id) const {
  48     return chunk()->LookupDestination(block_id);
  49   }
  50
  51   bool IsNextEmittedBlock(int block_id) const {
  52     return LookupDestination(block_id) == GetNextEmittedBlock();
  53   }
  54
  55   bool NeedsEagerFrame() const {
  56     return GetStackSlotCount() > 0 ||
  57         info()->is_non_deferred_calling() ||
  58         !info()->IsStub() ||
  59         info()->requires_frame();
  60   }
  61   bool NeedsDeferredFrame() const {
  62     return !NeedsEagerFrame() && info()->is_deferred_calling();
  63   }
  64
  65   LinkRegisterStatus GetLinkRegisterState() const {
  66     return frame_is_built_ ? kLRHasBeenSaved : kLRHasNotBeenSaved;
  67   }
  68
  69   // Try to generate code for the entire chunk, but it may fail if the
  70   // chunk contains constructs we cannot handle. Returns true if the
  71   // code generation attempt succeeded.
  72   bool GenerateCode();
  73
  74   // Finish the code by setting stack height, safepoint, and bailout
  75   // information on it.
  76   void FinishCode(Handle<Code> code);
  77
  78   enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
  79   // Support for converting LOperands to assembler types.
  80   Register ToRegister(LOperand* op) const;
  81   Register ToRegister32(LOperand* op) const;
  82   Operand ToOperand(LOperand* op);
  83   Operand ToOperand32(LOperand* op);
  84   MemOperand ToMemOperand(LOperand* op) const;
  85   Handle<Object> ToHandle(LConstantOperand* op) const;
  86
  87   template <class LI>
  88   Operand ToShiftedRightOperand32(LOperand* right, LI* shift_info);
  89
  90   int JSShiftAmountFromLConstant(LOperand* constant) {
  91     return ToInteger32(LConstantOperand::cast(constant)) & 0x1f;
  92   }
  93
  94   // TODO(jbramley): Examine these helpers and check that they make sense.
  95   // IsInteger32Constant returns true for smi constants, for example.
  96   bool IsInteger32Constant(LConstantOperand* op) const;
  97   bool IsSmi(LConstantOperand* op) const;
  98
  99   int32_t ToInteger32(LConstantOperand* op) const;
 100   Smi* ToSmi(LConstantOperand* op) const;
 101   double ToDouble(LConstantOperand* op) const;
 102   DoubleRegister ToDoubleRegister(LOperand* op) const;
 103
 104   // Declare methods that deal with the individual node types.
 105 #define DECLARE_DO(type) void Do##type(L##type* node);
 106   LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
 107 #undef DECLARE_DO
 108
 109  private:
 110   // Return a double scratch register which can be used locally
 111   // when generating code for a lithium instruction.
 112   DoubleRegister double_scratch() { return crankshaft_fp_scratch; }
 113
 114   // Deferred code support.
 115   void DoDeferredNumberTagD(LNumberTagD* instr);
 116   void DoDeferredStackCheck(LStackCheck* 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   int DefineDeoptimizationLiteral(Handle<Object> literal);
 201   void PopulateDeoptimizationData(Handle<Code> code);
 202   void PopulateDeoptimizationLiteralsWithInlinedFunctions();
 203
 204   MemOperand BuildSeqStringOperand(Register string,
 205                                    Register temp,
 206                                    LOperand* index,
 207                                    String::Encoding encoding);
 208   void DeoptimizeBranch(LInstruction* instr,
 209                         Deoptimizer::DeoptReason deopt_reason,
 210                         BranchType branch_type, Register reg = NoReg,
 211                         int bit = -1,
 212                         Deoptimizer::BailoutType* override_bailout_type = NULL);
 213   void Deoptimize(LInstruction* instr, Deoptimizer::DeoptReason deopt_reason,
 214                   Deoptimizer::BailoutType* override_bailout_type = NULL);
 215   void DeoptimizeIf(Condition cond, LInstruction* instr,
 216                     Deoptimizer::DeoptReason deopt_reason);
 217   void DeoptimizeIfZero(Register rt, LInstruction* instr,
 218                         Deoptimizer::DeoptReason deopt_reason);
 219   void DeoptimizeIfNotZero(Register rt, LInstruction* instr,
 220                            Deoptimizer::DeoptReason deopt_reason);
 221   void DeoptimizeIfNegative(Register rt, LInstruction* instr,
 222                             Deoptimizer::DeoptReason deopt_reason);
 223   void DeoptimizeIfSmi(Register rt, LInstruction* instr,
 224                        Deoptimizer::DeoptReason deopt_reason);
 225   void DeoptimizeIfNotSmi(Register rt, LInstruction* instr,
 226                           Deoptimizer::DeoptReason deopt_reason);
 227   void DeoptimizeIfRoot(Register rt, Heap::RootListIndex index,
 228                         LInstruction* instr,
 229                         Deoptimizer::DeoptReason deopt_reason);
 230   void DeoptimizeIfNotRoot(Register rt, Heap::RootListIndex index,
 231                            LInstruction* instr,
 232                            Deoptimizer::DeoptReason deopt_reason);
 233   void DeoptimizeIfNotHeapNumber(Register object, LInstruction* instr);
 234   void DeoptimizeIfMinusZero(DoubleRegister input, LInstruction* instr,
 235                              Deoptimizer::DeoptReason deopt_reason);
 236   void DeoptimizeIfBitSet(Register rt, int bit, LInstruction* instr,
 237                           Deoptimizer::DeoptReason deopt_reason);
 238   void DeoptimizeIfBitClear(Register rt, int bit, LInstruction* instr,
 239                             Deoptimizer::DeoptReason deopt_reason);
 240
 241   MemOperand PrepareKeyedExternalArrayOperand(Register key,
 242                                               Register base,
 243                                               Register scratch,
 244                                               bool key_is_smi,
 245                                               bool key_is_constant,
 246                                               int constant_key,
 247                                               ElementsKind elements_kind,
 248                                               int base_offset);
 249   MemOperand PrepareKeyedArrayOperand(Register base,
 250                                       Register elements,
 251                                       Register key,
 252                                       bool key_is_tagged,
 253                                       ElementsKind elements_kind,
 254                                       Representation representation,
 255                                       int base_offset);
 256
 257   void RegisterEnvironmentForDeoptimization(LEnvironment* environment,
 258                                             Safepoint::DeoptMode mode);
 259
 260   int GetStackSlotCount() const { return chunk()->spill_slot_count(); }
 261
 262   void AddDeferredCode(LDeferredCode* code) { deferred_.Add(code, zone()); }
 263
 264   // Emit frame translation commands for an environment.
 265   void WriteTranslation(LEnvironment* environment, Translation* translation);
 266
 267   void AddToTranslation(LEnvironment* environment,
 268                         Translation* translation,
 269                         LOperand* op,
 270                         bool is_tagged,
 271                         bool is_uint32,
 272                         int* object_index_pointer,
 273                         int* dematerialized_index_pointer);
 274
 275   void SaveCallerDoubles();
 276   void RestoreCallerDoubles();
 277
 278   // Code generation steps.  Returns true if code generation should continue.
 279   void GenerateBodyInstructionPre(LInstruction* instr) override;
 280   bool GeneratePrologue();
 281   bool GenerateDeferredCode();
 282   bool GenerateJumpTable();
 283   bool GenerateSafepointTable();
 284
 285   // Generates the custom OSR entrypoint and sets the osr_pc_offset.
 286   void GenerateOsrPrologue();
 287
 288   enum SafepointMode {
 289     RECORD_SIMPLE_SAFEPOINT,
 290     RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS
 291   };
 292
 293   void CallCode(Handle<Code> code,
 294                 RelocInfo::Mode mode,
 295                 LInstruction* instr);
 296
 297   void CallCodeGeneric(Handle<Code> code,
 298                        RelocInfo::Mode mode,
 299                        LInstruction* instr,
 300                        SafepointMode safepoint_mode);
 301
 302   void CallRuntime(const Runtime::Function* function,
 303                    int num_arguments,
 304                    LInstruction* instr,
 305                    SaveFPRegsMode save_doubles = kDontSaveFPRegs);
 306
 307   void CallRuntime(Runtime::FunctionId id,
 308                    int num_arguments,
 309                    LInstruction* instr) {
 310     const Runtime::Function* function = Runtime::FunctionForId(id);
 311     CallRuntime(function, num_arguments, instr);
 312   }
 313
 314   void LoadContextFromDeferred(LOperand* context);
 315   void CallRuntimeFromDeferred(Runtime::FunctionId id,
 316                                int argc,
 317                                LInstruction* instr,
 318                                LOperand* context);
 319
 320   // Generate a direct call to a known function.  Expects the function
 321   // to be in x1.
 322   void CallKnownFunction(Handle<JSFunction> function,
 323                          int formal_parameter_count, int arity,
 324                          LInstruction* instr);
 325
 326   // Support for recording safepoint and position information.
 327   void RecordAndWritePosition(int position) override;
 328   void RecordSafepoint(LPointerMap* pointers,
 329                        Safepoint::Kind kind,
 330                        int arguments,
 331                        Safepoint::DeoptMode mode);
 332   void RecordSafepoint(LPointerMap* pointers, Safepoint::DeoptMode mode);
 333   void RecordSafepoint(Safepoint::DeoptMode mode);
 334   void RecordSafepointWithRegisters(LPointerMap* pointers,
 335                                     int arguments,
 336                                     Safepoint::DeoptMode mode);
 337   void RecordSafepointWithLazyDeopt(LInstruction* instr,
 338                                     SafepointMode safepoint_mode);
 339
 340   void EnsureSpaceForLazyDeopt(int space_needed) override;
 341
 342   ZoneList<LEnvironment*> deoptimizations_;
 343   ZoneList<Deoptimizer::JumpTableEntry*> jump_table_;
 344   ZoneList<Handle<Object> > deoptimization_literals_;
 345   int inlined_function_count_;
 346   Scope* const scope_;
 347   TranslationBuffer translations_;
 348   ZoneList<LDeferredCode*> deferred_;
 349   int osr_pc_offset_;
 350   bool frame_is_built_;
 351
 352   // Builder that keeps track of safepoints in the code. The table itself is
 353   // emitted at the end of the generated code.
 354   SafepointTableBuilder safepoints_;
 355
 356   // Compiler from a set of parallel moves to a sequential list of moves.
 357   LGapResolver resolver_;
 358
 359   Safepoint::Kind expected_safepoint_kind_;
 360
 361   int old_position_;
 362
 363   class PushSafepointRegistersScope BASE_EMBEDDED {
 364    public:
 365     explicit PushSafepointRegistersScope(LCodeGen* codegen)
 366         : codegen_(codegen) {
 367       DCHECK(codegen_->info()->is_calling());
 368       DCHECK(codegen_->expected_safepoint_kind_ == Safepoint::kSimple);
 369       codegen_->expected_safepoint_kind_ = Safepoint::kWithRegisters;
 370
 371       UseScratchRegisterScope temps(codegen_->masm_);
 372       // Preserve the value of lr which must be saved on the stack (the call to
 373       // the stub will clobber it).
 374       Register to_be_pushed_lr =
 375           temps.UnsafeAcquire(StoreRegistersStateStub::to_be_pushed_lr());
 376       codegen_->masm_->Mov(to_be_pushed_lr, lr);
 377       StoreRegistersStateStub stub(codegen_->isolate());
 378       codegen_->masm_->CallStub(&stub);
 379     }
 380
 381     ~PushSafepointRegistersScope() {
 382       DCHECK(codegen_->expected_safepoint_kind_ == Safepoint::kWithRegisters);
 383       RestoreRegistersStateStub stub(codegen_->isolate());
 384       codegen_->masm_->CallStub(&stub);
 385       codegen_->expected_safepoint_kind_ = Safepoint::kSimple;
 386     }
 387
 388    private:
 389     LCodeGen* codegen_;
 390   };
 391
 392   friend class LDeferredCode;
 393   friend class SafepointGenerator;
 394   DISALLOW_COPY_AND_ASSIGN(LCodeGen);
 395 };
 396
 397
 398 class LDeferredCode: public ZoneObject {
 399  public:
 400   explicit LDeferredCode(LCodeGen* codegen)
 401       : codegen_(codegen),
 402         external_exit_(NULL),
 403         instruction_index_(codegen->current_instruction_) {
 404     codegen->AddDeferredCode(this);
 405   }
 406
 407   virtual ~LDeferredCode() { }
 408   virtual void Generate() = 0;
 409   virtual LInstruction* instr() = 0;
 410
 411   void SetExit(Label* exit) { external_exit_ = exit; }
 412   Label* entry() { return &entry_; }
 413   Label* exit() { return (external_exit_ != NULL) ? external_exit_ : &exit_; }
 414   int instruction_index() const { return instruction_index_; }
 415
 416  protected:
 417   LCodeGen* codegen() const { return codegen_; }
 418   MacroAssembler* masm() const { return codegen_->masm(); }
 419
 420  private:
 421   LCodeGen* codegen_;
 422   Label entry_;
 423   Label exit_;
 424   Label* external_exit_;
 425   int instruction_index_;
 426 };
 427
 428
 429 // This is the abstract class used by EmitBranchGeneric.
 430 // It is used to emit code for conditional branching. The Emit() function
 431 // emits code to branch when the condition holds and EmitInverted() emits
 432 // the branch when the inverted condition is verified.
 433 //
 434 // For actual examples of condition see the concrete implementation in
 435 // lithium-codegen-arm64.cc (e.g. BranchOnCondition, CompareAndBranch).
 436 class BranchGenerator BASE_EMBEDDED {
 437  public:
 438   explicit BranchGenerator(LCodeGen* codegen)
 439     : codegen_(codegen) { }
 440
 441   virtual ~BranchGenerator() { }
 442
 443   virtual void Emit(Label* label) const = 0;
 444   virtual void EmitInverted(Label* label) const = 0;
 445
 446  protected:
 447   MacroAssembler* masm() const { return codegen_->masm(); }
 448
 449   LCodeGen* codegen_;
 450 };
 451
 452 } }  // namespace v8::internal
 453
 454 #endif  // V8_ARM64_LITHIUM_CODEGEN_ARM64_H_