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 "arm64/lithium-arm64.h"
   9
  10 #include "arm64/lithium-gap-resolver-arm64.h"
  11 #include "deoptimizer.h"
  12 #include "lithium-codegen.h"
  13 #include "safepoint-table.h"
  14 #include "scopes.h"
  15 #include "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         deopt_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   // Support for converting LOperands to assembler types.
  79   // LOperand must be a register.
  80   Register ToRegister(LOperand* op) const;
  81   Register ToRegister32(LOperand* op) const;
  82   Operand ToOperand(LOperand* op);
  83   Operand ToOperand32I(LOperand* op);
  84   Operand ToOperand32U(LOperand* op);
  85   MemOperand ToMemOperand(LOperand* op) const;
  86   Handle<Object> ToHandle(LConstantOperand* op) const;
  87
  88   // TODO(jbramley): Examine these helpers and check that they make sense.
  89   // IsInteger32Constant returns true for smi constants, for example.
  90   bool IsInteger32Constant(LConstantOperand* op) const;
  91   bool IsSmi(LConstantOperand* op) const;
  92
  93   int32_t ToInteger32(LConstantOperand* op) const;
  94   Smi* ToSmi(LConstantOperand* op) const;
  95   double ToDouble(LConstantOperand* op) const;
  96   DoubleRegister ToDoubleRegister(LOperand* op) const;
  97
  98   // Declare methods that deal with the individual node types.
  99 #define DECLARE_DO(type) void Do##type(L##type* node);
 100   LITHIUM_CONCRETE_INSTRUCTION_LIST(DECLARE_DO)
 101 #undef DECLARE_DO
 102
 103  private:
 104   // Return a double scratch register which can be used locally
 105   // when generating code for a lithium instruction.
 106   DoubleRegister double_scratch() { return crankshaft_fp_scratch; }
 107
 108   // Deferred code support.
 109   void DoDeferredNumberTagD(LNumberTagD* instr);
 110   void DoDeferredStackCheck(LStackCheck* instr);
 111   void DoDeferredStringCharCodeAt(LStringCharCodeAt* instr);
 112   void DoDeferredStringCharFromCode(LStringCharFromCode* instr);
 113   void DoDeferredMathAbsTagged(LMathAbsTagged* instr,
 114                                Label* exit,
 115                                Label* allocation_entry);
 116
 117   enum IntegerSignedness { SIGNED_INT32, UNSIGNED_INT32 };
 118   void DoDeferredNumberTagU(LInstruction* instr,
 119                             LOperand* value,
 120                             LOperand* temp1,
 121                             LOperand* temp2);
 122   void DoDeferredTaggedToI(LTaggedToI* instr,
 123                            LOperand* value,
 124                            LOperand* temp1,
 125                            LOperand* temp2);
 126   void DoDeferredAllocate(LAllocate* instr);
 127   void DoDeferredInstanceOfKnownGlobal(LInstanceOfKnownGlobal* instr);
 128   void DoDeferredInstanceMigration(LCheckMaps* instr, Register object);
 129   void DoDeferredLoadMutableDouble(LLoadFieldByIndex* instr,
 130                                    Register result,
 131                                    Register object,
 132                                    Register index);
 133
 134   Operand ToOperand32(LOperand* op, IntegerSignedness signedness);
 135
 136   static Condition TokenToCondition(Token::Value op, bool is_unsigned);
 137   void EmitGoto(int block);
 138   void DoGap(LGap* instr);
 139
 140   // Generic version of EmitBranch. It contains some code to avoid emitting a
 141   // branch on the next emitted basic block where we could just fall-through.
 142   // You shouldn't use that directly but rather consider one of the helper like
 143   // LCodeGen::EmitBranch, LCodeGen::EmitCompareAndBranch...
 144   template<class InstrType>
 145   void EmitBranchGeneric(InstrType instr,
 146                          const BranchGenerator& branch);
 147
 148   template<class InstrType>
 149   void EmitBranch(InstrType instr, Condition condition);
 150
 151   template<class InstrType>
 152   void EmitCompareAndBranch(InstrType instr,
 153                             Condition condition,
 154                             const Register& lhs,
 155                             const Operand& rhs);
 156
 157   template<class InstrType>
 158   void EmitTestAndBranch(InstrType instr,
 159                          Condition condition,
 160                          const Register& value,
 161                          uint64_t mask);
 162
 163   template<class InstrType>
 164   void EmitBranchIfNonZeroNumber(InstrType instr,
 165                                  const FPRegister& value,
 166                                  const FPRegister& scratch);
 167
 168   template<class InstrType>
 169   void EmitBranchIfHeapNumber(InstrType instr,
 170                               const Register& value);
 171
 172   template<class InstrType>
 173   void EmitBranchIfRoot(InstrType instr,
 174                         const Register& value,
 175                         Heap::RootListIndex index);
 176
 177   // Emits optimized code to deep-copy the contents of statically known object
 178   // graphs (e.g. object literal boilerplate). Expects a pointer to the
 179   // allocated destination object in the result register, and a pointer to the
 180   // source object in the source register.
 181   void EmitDeepCopy(Handle<JSObject> object,
 182                     Register result,
 183                     Register source,
 184                     Register scratch,
 185                     int* offset,
 186                     AllocationSiteMode mode);
 187
 188   // Emits optimized code for %_IsString(x).  Preserves input register.
 189   // Returns the condition on which a final split to
 190   // true and false label should be made, to optimize fallthrough.
 191   Condition EmitIsString(Register input, Register temp1, Label* is_not_string,
 192                          SmiCheck check_needed);
 193
 194   int DefineDeoptimizationLiteral(Handle<Object> literal);
 195   void PopulateDeoptimizationData(Handle<Code> code);
 196   void PopulateDeoptimizationLiteralsWithInlinedFunctions();
 197
 198   MemOperand BuildSeqStringOperand(Register string,
 199                                    Register temp,
 200                                    LOperand* index,
 201                                    String::Encoding encoding);
 202   void DeoptimizeBranch(
 203       LEnvironment* environment,
 204       BranchType branch_type, Register reg = NoReg, int bit = -1,
 205       Deoptimizer::BailoutType* override_bailout_type = NULL);
 206   void Deoptimize(LEnvironment* environment,
 207                   Deoptimizer::BailoutType* override_bailout_type = NULL);
 208   void DeoptimizeIf(Condition cond, LEnvironment* environment);
 209   void DeoptimizeIfZero(Register rt, LEnvironment* environment);
 210   void DeoptimizeIfNotZero(Register rt, LEnvironment* environment);
 211   void DeoptimizeIfNegative(Register rt, LEnvironment* environment);
 212   void DeoptimizeIfSmi(Register rt, LEnvironment* environment);
 213   void DeoptimizeIfNotSmi(Register rt, LEnvironment* environment);
 214   void DeoptimizeIfRoot(Register rt,
 215                         Heap::RootListIndex index,
 216                         LEnvironment* environment);
 217   void DeoptimizeIfNotRoot(Register rt,
 218                            Heap::RootListIndex index,
 219                            LEnvironment* environment);
 220   void DeoptimizeIfMinusZero(DoubleRegister input, LEnvironment* environment);
 221   void DeoptimizeIfBitSet(Register rt, int bit, LEnvironment* environment);
 222   void DeoptimizeIfBitClear(Register rt, int bit, LEnvironment* environment);
 223
 224   MemOperand PrepareKeyedExternalArrayOperand(Register key,
 225                                               Register base,
 226                                               Register scratch,
 227                                               bool key_is_smi,
 228                                               bool key_is_constant,
 229                                               int constant_key,
 230                                               ElementsKind elements_kind,
 231                                               int additional_index);
 232   void CalcKeyedArrayBaseRegister(Register base,
 233                                   Register elements,
 234                                   Register key,
 235                                   bool key_is_tagged,
 236                                   ElementsKind elements_kind);
 237
 238   void RegisterEnvironmentForDeoptimization(LEnvironment* environment,
 239                                             Safepoint::DeoptMode mode);
 240
 241   int GetStackSlotCount() const { return chunk()->spill_slot_count(); }
 242
 243   void Abort(BailoutReason reason);
 244
 245   void AddDeferredCode(LDeferredCode* code) { deferred_.Add(code, zone()); }
 246
 247   // Emit frame translation commands for an environment.
 248   void WriteTranslation(LEnvironment* environment, Translation* translation);
 249
 250   void AddToTranslation(LEnvironment* environment,
 251                         Translation* translation,
 252                         LOperand* op,
 253                         bool is_tagged,
 254                         bool is_uint32,
 255                         int* object_index_pointer,
 256                         int* dematerialized_index_pointer);
 257
 258   void SaveCallerDoubles();
 259   void RestoreCallerDoubles();
 260
 261   // Code generation steps.  Returns true if code generation should continue.
 262   void GenerateBodyInstructionPre(LInstruction* instr) V8_OVERRIDE;
 263   bool GeneratePrologue();
 264   bool GenerateDeferredCode();
 265   bool GenerateDeoptJumpTable();
 266   bool GenerateSafepointTable();
 267
 268   // Generates the custom OSR entrypoint and sets the osr_pc_offset.
 269   void GenerateOsrPrologue();
 270
 271   enum SafepointMode {
 272     RECORD_SIMPLE_SAFEPOINT,
 273     RECORD_SAFEPOINT_WITH_REGISTERS_AND_NO_ARGUMENTS
 274   };
 275
 276   void CallCode(Handle<Code> code,
 277                 RelocInfo::Mode mode,
 278                 LInstruction* instr);
 279
 280   void CallCodeGeneric(Handle<Code> code,
 281                        RelocInfo::Mode mode,
 282                        LInstruction* instr,
 283                        SafepointMode safepoint_mode);
 284
 285   void CallRuntime(const Runtime::Function* function,
 286                    int num_arguments,
 287                    LInstruction* instr,
 288                    SaveFPRegsMode save_doubles = kDontSaveFPRegs);
 289
 290   void CallRuntime(Runtime::FunctionId id,
 291                    int num_arguments,
 292                    LInstruction* instr) {
 293     const Runtime::Function* function = Runtime::FunctionForId(id);
 294     CallRuntime(function, num_arguments, instr);
 295   }
 296
 297   void LoadContextFromDeferred(LOperand* context);
 298   void CallRuntimeFromDeferred(Runtime::FunctionId id,
 299                                int argc,
 300                                LInstruction* instr,
 301                                LOperand* context);
 302
 303   // Generate a direct call to a known function.
 304   // If the function is already loaded into x1 by the caller, function_reg may
 305   // be set to x1. Otherwise, it must be NoReg, and CallKnownFunction will
 306   // automatically load it.
 307   void CallKnownFunction(Handle<JSFunction> function,
 308                          int formal_parameter_count,
 309                          int arity,
 310                          LInstruction* instr,
 311                          Register function_reg = NoReg);
 312
 313   // Support for recording safepoint and position information.
 314   void RecordAndWritePosition(int position) V8_OVERRIDE;
 315   void RecordSafepoint(LPointerMap* pointers,
 316                        Safepoint::Kind kind,
 317                        int arguments,
 318                        Safepoint::DeoptMode mode);
 319   void RecordSafepoint(LPointerMap* pointers, Safepoint::DeoptMode mode);
 320   void RecordSafepoint(Safepoint::DeoptMode mode);
 321   void RecordSafepointWithRegisters(LPointerMap* pointers,
 322                                     int arguments,
 323                                     Safepoint::DeoptMode mode);
 324   void RecordSafepointWithRegistersAndDoubles(LPointerMap* pointers,
 325                                               int arguments,
 326                                               Safepoint::DeoptMode mode);
 327   void RecordSafepointWithLazyDeopt(LInstruction* instr,
 328                                     SafepointMode safepoint_mode);
 329
 330   void EnsureSpaceForLazyDeopt(int space_needed) V8_OVERRIDE;
 331
 332   ZoneList<LEnvironment*> deoptimizations_;
 333   ZoneList<Deoptimizer::JumpTableEntry*> deopt_jump_table_;
 334   ZoneList<Handle<Object> > deoptimization_literals_;
 335   int inlined_function_count_;
 336   Scope* const scope_;
 337   TranslationBuffer translations_;
 338   ZoneList<LDeferredCode*> deferred_;
 339   int osr_pc_offset_;
 340   bool frame_is_built_;
 341
 342   // Builder that keeps track of safepoints in the code. The table itself is
 343   // emitted at the end of the generated code.
 344   SafepointTableBuilder safepoints_;
 345
 346   // Compiler from a set of parallel moves to a sequential list of moves.
 347   LGapResolver resolver_;
 348
 349   Safepoint::Kind expected_safepoint_kind_;
 350
 351   int old_position_;
 352
 353   class PushSafepointRegistersScope BASE_EMBEDDED {
 354    public:
 355     PushSafepointRegistersScope(LCodeGen* codegen,
 356                                 Safepoint::Kind kind)
 357         : codegen_(codegen) {
 358       ASSERT(codegen_->info()->is_calling());
 359       ASSERT(codegen_->expected_safepoint_kind_ == Safepoint::kSimple);
 360       codegen_->expected_safepoint_kind_ = kind;
 361
 362       UseScratchRegisterScope temps(codegen_->masm_);
 363       // Preserve the value of lr which must be saved on the stack (the call to
 364       // the stub will clobber it).
 365       Register to_be_pushed_lr =
 366           temps.UnsafeAcquire(StoreRegistersStateStub::to_be_pushed_lr());
 367       codegen_->masm_->Mov(to_be_pushed_lr, lr);
 368       switch (codegen_->expected_safepoint_kind_) {
 369         case Safepoint::kWithRegisters: {
 370           StoreRegistersStateStub stub(codegen_->isolate(), kDontSaveFPRegs);
 371           codegen_->masm_->CallStub(&stub);
 372           break;
 373         }
 374         case Safepoint::kWithRegistersAndDoubles: {
 375           StoreRegistersStateStub stub(codegen_->isolate(), kSaveFPRegs);
 376           codegen_->masm_->CallStub(&stub);
 377           break;
 378         }
 379         default:
 380           UNREACHABLE();
 381       }
 382     }
 383
 384     ~PushSafepointRegistersScope() {
 385       Safepoint::Kind kind = codegen_->expected_safepoint_kind_;
 386       ASSERT((kind & Safepoint::kWithRegisters) != 0);
 387       switch (kind) {
 388         case Safepoint::kWithRegisters: {
 389           RestoreRegistersStateStub stub(codegen_->isolate(), kDontSaveFPRegs);
 390           codegen_->masm_->CallStub(&stub);
 391           break;
 392         }
 393         case Safepoint::kWithRegistersAndDoubles: {
 394           RestoreRegistersStateStub stub(codegen_->isolate(), kSaveFPRegs);
 395           codegen_->masm_->CallStub(&stub);
 396           break;
 397         }
 398         default:
 399           UNREACHABLE();
 400       }
 401       codegen_->expected_safepoint_kind_ = Safepoint::kSimple;
 402     }
 403
 404    private:
 405     LCodeGen* codegen_;
 406   };
 407
 408   friend class LDeferredCode;
 409   friend class SafepointGenerator;
 410   DISALLOW_COPY_AND_ASSIGN(LCodeGen);
 411 };
 412
 413
 414 class LDeferredCode: public ZoneObject {
 415  public:
 416   explicit LDeferredCode(LCodeGen* codegen)
 417       : codegen_(codegen),
 418         external_exit_(NULL),
 419         instruction_index_(codegen->current_instruction_) {
 420     codegen->AddDeferredCode(this);
 421   }
 422
 423   virtual ~LDeferredCode() { }
 424   virtual void Generate() = 0;
 425   virtual LInstruction* instr() = 0;
 426
 427   void SetExit(Label* exit) { external_exit_ = exit; }
 428   Label* entry() { return &entry_; }
 429   Label* exit() { return (external_exit_ != NULL) ? external_exit_ : &exit_; }
 430   int instruction_index() const { return instruction_index_; }
 431
 432  protected:
 433   LCodeGen* codegen() const { return codegen_; }
 434   MacroAssembler* masm() const { return codegen_->masm(); }
 435
 436  private:
 437   LCodeGen* codegen_;
 438   Label entry_;
 439   Label exit_;
 440   Label* external_exit_;
 441   int instruction_index_;
 442 };
 443
 444
 445 // This is the abstract class used by EmitBranchGeneric.
 446 // It is used to emit code for conditional branching. The Emit() function
 447 // emits code to branch when the condition holds and EmitInverted() emits
 448 // the branch when the inverted condition is verified.
 449 //
 450 // For actual examples of condition see the concrete implementation in
 451 // lithium-codegen-arm64.cc (e.g. BranchOnCondition, CompareAndBranch).
 452 class BranchGenerator BASE_EMBEDDED {
 453  public:
 454   explicit BranchGenerator(LCodeGen* codegen)
 455     : codegen_(codegen) { }
 456
 457   virtual ~BranchGenerator() { }
 458
 459   virtual void Emit(Label* label) const = 0;
 460   virtual void EmitInverted(Label* label) const = 0;
 461
 462  protected:
 463   MacroAssembler* masm() const { return codegen_->masm(); }
 464
 465   LCodeGen* codegen_;
 466 };
 467
 468 } }  // namespace v8::internal
 469
 470 #endif  // V8_ARM64_LITHIUM_CODEGEN_ARM64_H_