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         pushed_arguments_(0) {
  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   enum StackMode { kMustUseFramePointer, kCanUseStackPointer };
  85   MemOperand ToMemOperand(LOperand* op,
  86                           StackMode stack_mode = kCanUseStackPointer) const;
  87   Handle<Object> ToHandle(LConstantOperand* op) const;
  88
  89   template <class LI>
  90   Operand ToShiftedRightOperand32(LOperand* right, LI* shift_info);
  91
  92   int JSShiftAmountFromLConstant(LOperand* constant) {
  93     return ToInteger32(LConstantOperand::cast(constant)) & 0x1f;
  94   }
  95
  96   // TODO(jbramley): Examine these helpers and check that they make sense.
  97   // IsInteger32Constant returns true for smi constants, for example.
  98   bool IsInteger32Constant(LConstantOperand* op) const;
  99   bool IsSmi(LConstantOperand* op) const;
 100
 101   int32_t ToInteger32(LConstantOperand* op) const;
 102   Smi* ToSmi(LConstantOperand* op) const;
 103   double ToDouble(LConstantOperand* op) const;
 104   DoubleRegister ToDoubleRegister(LOperand* op) const;
 105
 106   // Declare methods that deal with the individual node types.
 107 #define DECLARE_DO(type) void Do##type(L##type* node);
 108   LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
 109 #undef DECLARE_DO
 110
 111  private:
 112   // Return a double scratch register which can be used locally
 113   // when generating code for a lithium instruction.
 114   DoubleRegister double_scratch() { return crankshaft_fp_scratch; }
 115
 116   // Deferred code support.
 117   void DoDeferredNumberTagD(LNumberTagD* instr);
 118   void DoDeferredStackCheck(LStackCheck* instr);
 119   void DoDeferredMaybeGrowElements(LMaybeGrowElements* instr);
 120   void DoDeferredStringCharCodeAt(LStringCharCodeAt* instr);
 121   void DoDeferredStringCharFromCode(LStringCharFromCode* instr);
 122   void DoDeferredMathAbsTagged(LMathAbsTagged* instr,
 123                                Label* exit,
 124                                Label* allocation_entry);
 125
 126   void DoDeferredNumberTagU(LInstruction* instr,
 127                             LOperand* value,
 128                             LOperand* temp1,
 129                             LOperand* temp2);
 130   void DoDeferredTaggedToI(LTaggedToI* instr,
 131                            LOperand* value,
 132                            LOperand* temp1,
 133                            LOperand* temp2);
 134   void DoDeferredAllocate(LAllocate* instr);
 135   void DoDeferredInstanceMigration(LCheckMaps* instr, Register object);
 136   void DoDeferredLoadMutableDouble(LLoadFieldByIndex* instr,
 137                                    Register result,
 138                                    Register object,
 139                                    Register index);
 140
 141   static Condition TokenToCondition(Token::Value op, bool is_unsigned);
 142   void EmitGoto(int block);
 143   void DoGap(LGap* instr);
 144
 145   // Generic version of EmitBranch. It contains some code to avoid emitting a
 146   // branch on the next emitted basic block where we could just fall-through.
 147   // You shouldn't use that directly but rather consider one of the helper like
 148   // LCodeGen::EmitBranch, LCodeGen::EmitCompareAndBranch...
 149   template<class InstrType>
 150   void EmitBranchGeneric(InstrType instr,
 151                          const BranchGenerator& branch);
 152
 153   template<class InstrType>
 154   void EmitBranch(InstrType instr, Condition condition);
 155
 156   template<class InstrType>
 157   void EmitCompareAndBranch(InstrType instr,
 158                             Condition condition,
 159                             const Register& lhs,
 160                             const Operand& rhs);
 161
 162   template<class InstrType>
 163   void EmitTestAndBranch(InstrType instr,
 164                          Condition condition,
 165                          const Register& value,
 166                          uint64_t mask);
 167
 168   template<class InstrType>
 169   void EmitBranchIfNonZeroNumber(InstrType instr,
 170                                  const FPRegister& value,
 171                                  const FPRegister& scratch);
 172
 173   template<class InstrType>
 174   void EmitBranchIfHeapNumber(InstrType instr,
 175                               const Register& value);
 176
 177   template<class InstrType>
 178   void EmitBranchIfRoot(InstrType instr,
 179                         const Register& value,
 180                         Heap::RootListIndex index);
 181
 182   // Emits optimized code to deep-copy the contents of statically known object
 183   // graphs (e.g. object literal boilerplate). Expects a pointer to the
 184   // allocated destination object in the result register, and a pointer to the
 185   // source object in the source register.
 186   void EmitDeepCopy(Handle<JSObject> object,
 187                     Register result,
 188                     Register source,
 189                     Register scratch,
 190                     int* offset,
 191                     AllocationSiteMode mode);
 192
 193   template <class T>
 194   void EmitVectorLoadICRegisters(T* instr);
 195   template <class T>
 196   void EmitVectorStoreICRegisters(T* instr);
 197
 198   // Emits optimized code for %_IsString(x).  Preserves input register.
 199   // Returns the condition on which a final split to
 200   // true and false label should be made, to optimize fallthrough.
 201   Condition EmitIsString(Register input, Register temp1, Label* is_not_string,
 202                          SmiCheck check_needed);
 203
 204   void PopulateDeoptimizationData(Handle<Code> code);
 205   void PopulateDeoptimizationLiteralsWithInlinedFunctions();
 206
 207   MemOperand BuildSeqStringOperand(Register string,
 208                                    Register temp,
 209                                    LOperand* index,
 210                                    String::Encoding encoding);
 211   void DeoptimizeBranch(LInstruction* instr,
 212                         Deoptimizer::DeoptReason deopt_reason,
 213                         BranchType branch_type, Register reg = NoReg,
 214                         int bit = -1,
 215                         Deoptimizer::BailoutType* override_bailout_type = NULL);
 216   void Deoptimize(LInstruction* instr, Deoptimizer::DeoptReason deopt_reason,
 217                   Deoptimizer::BailoutType* override_bailout_type = NULL);
 218   void DeoptimizeIf(Condition cond, LInstruction* instr,
 219                     Deoptimizer::DeoptReason deopt_reason);
 220   void DeoptimizeIfZero(Register rt, LInstruction* instr,
 221                         Deoptimizer::DeoptReason deopt_reason);
 222   void DeoptimizeIfNotZero(Register rt, LInstruction* instr,
 223                            Deoptimizer::DeoptReason deopt_reason);
 224   void DeoptimizeIfNegative(Register rt, LInstruction* instr,
 225                             Deoptimizer::DeoptReason deopt_reason);
 226   void DeoptimizeIfSmi(Register rt, LInstruction* instr,
 227                        Deoptimizer::DeoptReason deopt_reason);
 228   void DeoptimizeIfNotSmi(Register rt, LInstruction* instr,
 229                           Deoptimizer::DeoptReason deopt_reason);
 230   void DeoptimizeIfRoot(Register rt, Heap::RootListIndex index,
 231                         LInstruction* instr,
 232                         Deoptimizer::DeoptReason deopt_reason);
 233   void DeoptimizeIfNotRoot(Register rt, Heap::RootListIndex index,
 234                            LInstruction* instr,
 235                            Deoptimizer::DeoptReason deopt_reason);
 236   void DeoptimizeIfNotHeapNumber(Register object, LInstruction* instr);
 237   void DeoptimizeIfMinusZero(DoubleRegister input, LInstruction* instr,
 238                              Deoptimizer::DeoptReason deopt_reason);
 239   void DeoptimizeIfBitSet(Register rt, int bit, LInstruction* instr,
 240                           Deoptimizer::DeoptReason deopt_reason);
 241   void DeoptimizeIfBitClear(Register rt, int bit, LInstruction* instr,
 242                             Deoptimizer::DeoptReason deopt_reason);
 243
 244   MemOperand PrepareKeyedExternalArrayOperand(Register key,
 245                                               Register base,
 246                                               Register scratch,
 247                                               bool key_is_smi,
 248                                               bool key_is_constant,
 249                                               int constant_key,
 250                                               ElementsKind elements_kind,
 251                                               int base_offset);
 252   MemOperand PrepareKeyedArrayOperand(Register base,
 253                                       Register elements,
 254                                       Register key,
 255                                       bool key_is_tagged,
 256                                       ElementsKind elements_kind,
 257                                       Representation representation,
 258                                       int base_offset);
 259
 260   void RegisterEnvironmentForDeoptimization(LEnvironment* environment,
 261                                             Safepoint::DeoptMode mode);
 262
 263   int GetStackSlotCount() const { return chunk()->spill_slot_count(); }
 264
 265   void AddDeferredCode(LDeferredCode* code) { deferred_.Add(code, zone()); }
 266
 267   // Emit frame translation commands for an environment.
 268   void WriteTranslation(LEnvironment* environment, Translation* translation);
 269
 270   void AddToTranslation(LEnvironment* environment,
 271                         Translation* translation,
 272                         LOperand* op,
 273                         bool is_tagged,
 274                         bool is_uint32,
 275                         int* object_index_pointer,
 276                         int* dematerialized_index_pointer);
 277
 278   void SaveCallerDoubles();
 279   void RestoreCallerDoubles();
 280
 281   // Code generation steps.  Returns true if code generation should continue.
 282   void GenerateBodyInstructionPre(LInstruction* instr) override;
 283   bool GeneratePrologue();
 284   bool GenerateDeferredCode();
 285   bool GenerateJumpTable();
 286   bool GenerateSafepointTable();
 287
 288   // Generates the custom OSR entrypoint and sets the osr_pc_offset.
 289   void GenerateOsrPrologue();
 290
 291   enum SafepointMode {
 292     RECORD_SIMPLE_SAFEPOINT,
 293     RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS
 294   };
 295
 296   void CallCode(Handle<Code> code,
 297                 RelocInfo::Mode mode,
 298                 LInstruction* instr);
 299
 300   void CallCodeGeneric(Handle<Code> code,
 301                        RelocInfo::Mode mode,
 302                        LInstruction* instr,
 303                        SafepointMode safepoint_mode);
 304
 305   void CallRuntime(const Runtime::Function* function,
 306                    int num_arguments,
 307                    LInstruction* instr,
 308                    SaveFPRegsMode save_doubles = kDontSaveFPRegs);
 309
 310   void CallRuntime(Runtime::FunctionId id,
 311                    int num_arguments,
 312                    LInstruction* instr) {
 313     const Runtime::Function* function = Runtime::FunctionForId(id);
 314     CallRuntime(function, num_arguments, instr);
 315   }
 316
 317   void LoadContextFromDeferred(LOperand* context);
 318   void CallRuntimeFromDeferred(Runtime::FunctionId id,
 319                                int argc,
 320                                LInstruction* instr,
 321                                LOperand* context);
 322
 323   // Generate a direct call to a known function.  Expects the function
 324   // to be in x1.
 325   void CallKnownFunction(Handle<JSFunction> function,
 326                          int formal_parameter_count, int arity,
 327                          LInstruction* instr);
 328
 329   // Support for recording safepoint and position information.
 330   void RecordAndWritePosition(int position) override;
 331   void RecordSafepoint(LPointerMap* pointers,
 332                        Safepoint::Kind kind,
 333                        int arguments,
 334                        Safepoint::DeoptMode mode);
 335   void RecordSafepoint(LPointerMap* pointers, Safepoint::DeoptMode mode);
 336   void RecordSafepoint(Safepoint::DeoptMode mode);
 337   void RecordSafepointWithRegisters(LPointerMap* pointers,
 338                                     int arguments,
 339                                     Safepoint::DeoptMode mode);
 340   void RecordSafepointWithLazyDeopt(LInstruction* instr,
 341                                     SafepointMode safepoint_mode);
 342
 343   void EnsureSpaceForLazyDeopt(int space_needed) override;
 344
 345   ZoneList<LEnvironment*> deoptimizations_;
 346   ZoneList<Deoptimizer::JumpTableEntry*> jump_table_;
 347   int inlined_function_count_;
 348   Scope* const scope_;
 349   TranslationBuffer translations_;
 350   ZoneList<LDeferredCode*> deferred_;
 351   int osr_pc_offset_;
 352   bool frame_is_built_;
 353
 354   // Builder that keeps track of safepoints in the code. The table itself is
 355   // emitted at the end of the generated code.
 356   SafepointTableBuilder safepoints_;
 357
 358   // Compiler from a set of parallel moves to a sequential list of moves.
 359   LGapResolver resolver_;
 360
 361   Safepoint::Kind expected_safepoint_kind_;
 362
 363   // The number of arguments pushed onto the stack, either by this block or by a
 364   // predecessor.
 365   int pushed_arguments_;
 366
 367   void RecordPushedArgumentsDelta(int delta) {
 368     pushed_arguments_ += delta;
 369     DCHECK(pushed_arguments_ >= 0);
 370   }
 371
 372   int old_position_;
 373
 374   class PushSafepointRegistersScope BASE_EMBEDDED {
 375    public:
 376     explicit PushSafepointRegistersScope(LCodeGen* codegen)
 377         : codegen_(codegen) {
 378       DCHECK(codegen_->info()->is_calling());
 379       DCHECK(codegen_->expected_safepoint_kind_ == Safepoint::kSimple);
 380       codegen_->expected_safepoint_kind_ = Safepoint::kWithRegisters;
 381
 382       UseScratchRegisterScope temps(codegen_->masm_);
 383       // Preserve the value of lr which must be saved on the stack (the call to
 384       // the stub will clobber it).
 385       Register to_be_pushed_lr =
 386           temps.UnsafeAcquire(StoreRegistersStateStub::to_be_pushed_lr());
 387       codegen_->masm_->Mov(to_be_pushed_lr, lr);
 388       StoreRegistersStateStub stub(codegen_->isolate());
 389       codegen_->masm_->CallStub(&stub);
 390     }
 391
 392     ~PushSafepointRegistersScope() {
 393       DCHECK(codegen_->expected_safepoint_kind_ == Safepoint::kWithRegisters);
 394       RestoreRegistersStateStub stub(codegen_->isolate());
 395       codegen_->masm_->CallStub(&stub);
 396       codegen_->expected_safepoint_kind_ = Safepoint::kSimple;
 397     }
 398
 399    private:
 400     LCodeGen* codegen_;
 401   };
 402
 403   friend class LDeferredCode;
 404   friend class SafepointGenerator;
 405   DISALLOW_COPY_AND_ASSIGN(LCodeGen);
 406 };
 407
 408
 409 class LDeferredCode: public ZoneObject {
 410  public:
 411   explicit LDeferredCode(LCodeGen* codegen)
 412       : codegen_(codegen),
 413         external_exit_(NULL),
 414         instruction_index_(codegen->current_instruction_) {
 415     codegen->AddDeferredCode(this);
 416   }
 417
 418   virtual ~LDeferredCode() { }
 419   virtual void Generate() = 0;
 420   virtual LInstruction* instr() = 0;
 421
 422   void SetExit(Label* exit) { external_exit_ = exit; }
 423   Label* entry() { return &entry_; }
 424   Label* exit() { return (external_exit_ != NULL) ? external_exit_ : &exit_; }
 425   int instruction_index() const { return instruction_index_; }
 426
 427  protected:
 428   LCodeGen* codegen() const { return codegen_; }
 429   MacroAssembler* masm() const { return codegen_->masm(); }
 430
 431  private:
 432   LCodeGen* codegen_;
 433   Label entry_;
 434   Label exit_;
 435   Label* external_exit_;
 436   int instruction_index_;
 437 };
 438
 439
 440 // This is the abstract class used by EmitBranchGeneric.
 441 // It is used to emit code for conditional branching. The Emit() function
 442 // emits code to branch when the condition holds and EmitInverted() emits
 443 // the branch when the inverted condition is verified.
 444 //
 445 // For actual examples of condition see the concrete implementation in
 446 // lithium-codegen-arm64.cc (e.g. BranchOnCondition, CompareAndBranch).
 447 class BranchGenerator BASE_EMBEDDED {
 448  public:
 449   explicit BranchGenerator(LCodeGen* codegen)
 450     : codegen_(codegen) { }
 451
 452   virtual ~BranchGenerator() { }
 453
 454   virtual void Emit(Label* label) const = 0;
 455   virtual void EmitInverted(Label* label) const = 0;
 456
 457  protected:
 458   MacroAssembler* masm() const { return codegen_->masm(); }
 459
 460   LCodeGen* codegen_;
 461 };
 462
 463 }  // namespace internal
 464 }  // namespace v8
 465
 466 #endif  // V8_ARM64_LITHIUM_CODEGEN_ARM64_H_