Port irregexp bytecode compiler and interpreter from V8 r24065.

runtime/vm/regexp_assembler.h

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef VM_REGEXP_ASSEMBLER_H_
 #define VM_REGEXP_ASSEMBLER_H_
 
 #include "vm/assembler.h"
 #include "vm/intermediate_language.h"
 #include "vm/object.h"
 
 namespace dart {
 
 // Utility function for the DotPrinter
 void PrintUtf16(uint16_t c);
 
 
 /// Convenience wrapper around a BlockEntryInstr pointer.
 class BlockLabel : public ValueObject {
+  // Used by the IR assembler.
  public:
   BlockLabel()
     : block_(new JoinEntryInstr(-1, -1)),
       is_bound_(false),
-      is_linked_(false) { }
-
-  BlockLabel(const BlockLabel& that)
-    : ValueObject(),
-      block_(that.block_),
-      is_bound_(that.is_bound_),
-      is_linked_(that.is_linked_) { }
-
-  BlockLabel& operator=(const BlockLabel& that) {
-    block_ = that.block_;
-    is_bound_ = that.is_bound_;
-    is_linked_ = that.is_linked_;
-    return *this;
-  }
+      is_linked_(false),
+      pos_(-1) { }
 
   JoinEntryInstr* block() const { return block_; }
 
   bool IsBound() const { return is_bound_; }
   void SetBound(intptr_t block_id) {
     ASSERT(!is_bound_);
     block_->set_block_id(block_id);
     is_bound_ = true;
   }
 
   bool IsLinked() const { return !is_bound_ && is_linked_; }
   void SetLinked() {
     is_linked_ = true;
   }
 
   intptr_t Position() const {
     ASSERT(IsBound());
     return block_->block_id();
   }
 
  private:
   JoinEntryInstr* block_;
 
   bool is_bound_;
   bool is_linked_;
+
+  // Used by the bytecode assembler.
+ public:
+  ~BlockLabel() {
+    ASSERT(!is_linked());
+  }
+
+  intptr_t pos() const {
+    return pos_;
+  }
+  bool is_bound() const { return IsBound(); }
+  bool is_linked() const { return IsLinked(); }
+
+  void Unuse() {
+    pos_ = 0;
+    is_bound_ = false;
+    is_linked_ = false;
+  }
+
+  void bind_to(intptr_t pos) {
+    pos_ = pos;
+    is_bound_ = true;
+    is_linked_ = false;
+    ASSERT(is_bound());
+  }
+
+  void link_to(intptr_t pos) {
+    pos_ = pos;
+    is_bound_ = false;
+    is_linked_ = true;
+    ASSERT(is_linked());
+  }
+
+ private:
+  intptr_t pos_;
 };
 
 
 class RegExpMacroAssembler : public ZoneAllocated {
  public:
   // The implementation must be able to handle at least:
   static const intptr_t kMaxRegister = (1 << 16) - 1;
   static const intptr_t kMaxCPOffset = (1 << 15) - 1;
   static const intptr_t kMinCPOffset = -(1 << 15);
 
   static const intptr_t kTableSizeBits = 7;
   static const intptr_t kTableSize = 1 << kTableSizeBits;
   static const intptr_t kTableMask = kTableSize - 1;
 
   enum {
     kParamStringIndex = 0,
     kParamStartOffsetIndex,
     kParamCount
   };
 
   enum IrregexpImplementation {
+    kBytecodeImplementation,
     kIRImplementation
   };
 
   explicit RegExpMacroAssembler(Zone* zone);
   virtual ~RegExpMacroAssembler();
   // The maximal number of pushes between stack checks. Users must supply
   // kCheckStackLimit flag to push operations (instead of kNoStackLimitCheck)
   // at least once for every stack_limit() pushes that are executed.
   virtual intptr_t stack_limit_slack() = 0;
   virtual bool CanReadUnaligned() = 0;
@@ skipping 116 matching lines @@
   }
 
   Zone* zone() const { return zone_; }
 
  private:
   bool slow_safe_compiler_;
   bool global_mode_;
   Zone* zone_;
 };
 
-
-class IRRegExpMacroAssembler : public RegExpMacroAssembler {
- public:
-  // Type of input string to generate code for.
-  enum Mode { ASCII = 1, UC16 = 2 };
-
-  // Result of calling generated native RegExp code.
-  // RETRY: Something significant changed during execution, and the matching
-  //        should be retried from scratch.
-  // EXCEPTION: Something failed during execution. If no exception has been
-  //        thrown, it's an internal out-of-memory, and the caller should
-  //        throw the exception.
-  // FAILURE: Matching failed.
-  // SUCCESS: Matching succeeded, and the output array has been filled with
-  //        capture positions.
-  enum Result { RETRY = -2, EXCEPTION = -1, FAILURE = 0, SUCCESS = 1 };
-
-  IRRegExpMacroAssembler(intptr_t specialization_cid,
-                         intptr_t capture_count,
-                         const ParsedFunction* parsed_function,
-                         const ZoneGrowableArray<const ICData*>& ic_data_array,
-                         Zone* zone);
-  virtual ~IRRegExpMacroAssembler();
-
-  virtual bool CanReadUnaligned();
-
-  // Compares two-byte strings case insensitively.
-  // Called from generated RegExp code.
-  static RawBool* CaseInsensitiveCompareUC16(
-      RawString* str_raw,
-      RawSmi* lhs_index_raw,
-      RawSmi* rhs_index_raw,
-      RawSmi* length_raw);
-
-  static RawArray* Execute(const Function& function,
-                           const String& input,
-                           const Smi& start_offset,
-                           Zone* zone);
-
-  virtual bool IsClosed() const { return (current_instruction_ == NULL); }
-
-  virtual intptr_t stack_limit_slack();
-  virtual void AdvanceCurrentPosition(intptr_t by);
-  virtual void AdvanceRegister(intptr_t reg, intptr_t by);
-  virtual void Backtrack();
-  virtual void BindBlock(BlockLabel* label);
-  virtual void CheckAtStart(BlockLabel* on_at_start);
-  virtual void CheckCharacter(uint32_t c, BlockLabel* on_equal);
-  virtual void CheckCharacterAfterAnd(uint32_t c,
-                                      uint32_t mask,
-                                      BlockLabel* on_equal);
-  virtual void CheckCharacterGT(uint16_t limit, BlockLabel* on_greater);
-  virtual void CheckCharacterLT(uint16_t limit, BlockLabel* on_less);
-  // A "greedy loop" is a loop that is both greedy and with a simple
-  // body. It has a particularly simple implementation.
-  virtual void CheckGreedyLoop(BlockLabel* on_tos_equals_current_position);
-  virtual void CheckNotAtStart(BlockLabel* on_not_at_start);
-  virtual void CheckNotBackReference(intptr_t start_reg,
-                                     BlockLabel* on_no_match);
-  virtual void CheckNotBackReferenceIgnoreCase(intptr_t start_reg,
-                                               BlockLabel* on_no_match);
-  virtual void CheckNotCharacter(uint32_t c, BlockLabel* on_not_equal);
-  virtual void CheckNotCharacterAfterAnd(uint32_t c,
-                                         uint32_t mask,
-                                         BlockLabel* on_not_equal);
-  virtual void CheckNotCharacterAfterMinusAnd(uint16_t c,
-                                              uint16_t minus,
-                                              uint16_t mask,
-                                              BlockLabel* on_not_equal);
-  virtual void CheckCharacterInRange(uint16_t from,
-                                     uint16_t to,
-                                     BlockLabel* on_in_range);
-  virtual void CheckCharacterNotInRange(uint16_t from,
-                                        uint16_t to,
-                                        BlockLabel* on_not_in_range);
-  virtual void CheckBitInTable(const TypedData& table, BlockLabel* on_bit_set);
-
-  // Checks whether the given offset from the current position is before
-  // the end of the string.
-  virtual void CheckPosition(intptr_t cp_offset, BlockLabel* on_outside_input);
-  virtual bool CheckSpecialCharacterClass(
-      uint16_t type, BlockLabel* on_no_match);
-  virtual void Fail();
-  virtual void IfRegisterGE(intptr_t reg,
-                            intptr_t comparand, BlockLabel* if_ge);
-  virtual void IfRegisterLT(intptr_t reg,
-                            intptr_t comparand, BlockLabel* if_lt);
-  virtual void IfRegisterEqPos(intptr_t reg, BlockLabel* if_eq);
-  virtual IrregexpImplementation Implementation();
-  virtual void GoTo(BlockLabel* to);
-  virtual void LoadCurrentCharacter(intptr_t cp_offset,
-                                    BlockLabel* on_end_of_input,
-                                    bool check_bounds = true,
-                                    intptr_t characters = 1);
-  virtual void PopCurrentPosition();
-  virtual void PopRegister(intptr_t register_index);
-  virtual void Print(const char* str);
-  virtual void PushBacktrack(BlockLabel* label);
-  virtual void PushCurrentPosition();
-  virtual void PushRegister(intptr_t register_index);
-  virtual void ReadCurrentPositionFromRegister(intptr_t reg);
-  virtual void ReadStackPointerFromRegister(intptr_t reg);
-  virtual void SetCurrentPositionFromEnd(intptr_t by);
-  virtual void SetRegister(intptr_t register_index, intptr_t to);
-  virtual bool Succeed();
-  virtual void WriteCurrentPositionToRegister(intptr_t reg, intptr_t cp_offset);
-  virtual void ClearRegisters(intptr_t reg_from, intptr_t reg_to);
-  virtual void WriteStackPointerToRegister(intptr_t reg);
-
-  virtual void PrintBlocks();
-
-  IndirectGotoInstr* backtrack_goto() const { return backtrack_goto_; }
-  GraphEntryInstr* graph_entry() const { return entry_block_; }
-
-  intptr_t num_stack_locals() const { return local_id_.Count(); }
-  intptr_t num_blocks() const { return block_id_.Count(); }
-
-  // Generate a dispatch block implementing backtracking. Must be done after
-  // graph construction.
-  void GenerateBacktrackBlock();
-
-  // Allocate the actual registers array once its size is known. Must be done
-  // after graph construction.
-  void FinalizeRegistersArray();
-
- private:
-  // Generate the contents of preset blocks. The entry block is the entry point
-  // of the generated code.
-  void GenerateEntryBlock();
-  // Copies capture indices into the result area and returns true.
-  void GenerateSuccessBlock();
-  // Returns false.
-  void GenerateExitBlock();
-
-  enum ComparisonKind {
-    kEQ,
-    kNE,
-    kLT,
-    kGT,
-    kLTE,
-    kGTE,
-  };
-
-  struct InstanceCallDescriptor {
-    // Standard (i.e. most non-Smi) functions.
-    explicit InstanceCallDescriptor(const String& name)
-      : name(name),
-        token_kind(Token::kILLEGAL),
-        checked_argument_count(1) { }
-
-    InstanceCallDescriptor(const String& name,
-                           Token::Kind token_kind,
-                           intptr_t checked_argument_count)
-      : name(name),
-        token_kind(token_kind),
-        checked_argument_count(checked_argument_count) { }
-
-    // Special cases for Smi and indexing functions.
-    static InstanceCallDescriptor FromToken(Token::Kind token_kind) {
-      switch (token_kind) {
-        case Token::kEQ: return InstanceCallDescriptor(
-                  Symbols::EqualOperator(), token_kind, 2);
-        case Token::kADD: return InstanceCallDescriptor(
-                Symbols::Plus(), token_kind, 2);
-        case Token::kSUB: return InstanceCallDescriptor(
-                Symbols::Minus(), token_kind, 2);
-        case Token::kBIT_OR: return InstanceCallDescriptor(
-                Symbols::BitOr(), token_kind, 2);
-        case Token::kBIT_AND: return InstanceCallDescriptor(
-                Symbols::BitAnd(), token_kind, 2);
-        case Token::kLT: return InstanceCallDescriptor(
-                Symbols::LAngleBracket(), token_kind, 2);
-        case Token::kLTE: return InstanceCallDescriptor(
-                Symbols::LessEqualOperator(), token_kind, 2);
-        case Token::kGT: return InstanceCallDescriptor(
-                Symbols::RAngleBracket(), token_kind, 2);
-        case Token::kGTE: return InstanceCallDescriptor(
-                Symbols::GreaterEqualOperator(), token_kind, 2);
-        case Token::kNEGATE: return InstanceCallDescriptor(
-                Symbols::UnaryMinus(), token_kind, 1);
-        case Token::kINDEX: return InstanceCallDescriptor(
-                Symbols::IndexToken(), token_kind, 2);
-        case Token::kASSIGN_INDEX: return InstanceCallDescriptor(
-                Symbols::AssignIndexToken(), token_kind, 2);
-        default:
-          UNREACHABLE();
-      }
-      UNREACHABLE();
-      return InstanceCallDescriptor(Symbols::Empty());
-    }
-
-    const String& name;
-    Token::Kind token_kind;
-    intptr_t checked_argument_count;
-  };
-
-  LocalVariable* Local(const String& name);
-  LocalVariable* Parameter(const String& name, intptr_t index) const;
-
-  ConstantInstr* Int64Constant(int64_t value) const;
-  ConstantInstr* Uint64Constant(uint64_t value) const;
-  ConstantInstr* BoolConstant(bool value) const;
-  ConstantInstr* StringConstant(const char* value) const;
-
-  // The word character map static member of the RegExp class.
-  // Byte map of one byte characters with a 0xff if the character is a word
-  // character (digit, letter or underscore) and 0x00 otherwise.
-  // Used by generated RegExp code.
-  ConstantInstr* WordCharacterMapConstant() const;
-
-  ComparisonInstr* Comparison(ComparisonKind kind,
-                              PushArgumentInstr* lhs,
-                              PushArgumentInstr* rhs);
-  ComparisonInstr* Comparison(ComparisonKind kind,
-                              Definition* lhs,
-                              Definition* rhs);
-
-  InstanceCallInstr* InstanceCall(const InstanceCallDescriptor& desc,
-                                  PushArgumentInstr* arg1) const;
-  InstanceCallInstr* InstanceCall(const InstanceCallDescriptor& desc,
-                                  PushArgumentInstr* arg1,
-                                  PushArgumentInstr* arg2) const;
-  InstanceCallInstr* InstanceCall(const InstanceCallDescriptor& desc,
-                                  PushArgumentInstr* arg1,
-                                  PushArgumentInstr* arg2,
-                                  PushArgumentInstr* arg3) const;
-  InstanceCallInstr* InstanceCall(
-      const InstanceCallDescriptor& desc,
-      ZoneGrowableArray<PushArgumentInstr*>* arguments) const;
-
-  StaticCallInstr* StaticCall(const Function& function) const;
-  StaticCallInstr* StaticCall(const Function& function,
-                              PushArgumentInstr* arg1) const;
-  StaticCallInstr* StaticCall(const Function& function,
-                              PushArgumentInstr* arg1,
-                              PushArgumentInstr* arg2) const;
-  StaticCallInstr* StaticCall(
-      const Function& function,
-      ZoneGrowableArray<PushArgumentInstr*>* arguments) const;
-
-  // Creates a new block consisting simply of a goto to dst.
-  TargetEntryInstr* TargetWithJoinGoto(JoinEntryInstr* dst);
-  IndirectEntryInstr* IndirectWithJoinGoto(JoinEntryInstr* dst);
-
-  // Adds, respectively subtracts lhs and rhs and returns the result.
-  Definition* Add(PushArgumentInstr* lhs, PushArgumentInstr* rhs);
-  Definition* Sub(PushArgumentInstr* lhs, PushArgumentInstr* rhs);
-
-  LoadLocalInstr* LoadLocal(LocalVariable* local) const;
-  void StoreLocal(LocalVariable* local, Value* value);
-
-  PushArgumentInstr* PushArgument(Value* value);
-  PushArgumentInstr* PushLocal(LocalVariable* local);
-
-  PushArgumentInstr* PushRegisterIndex(intptr_t reg);
-  Value* LoadRegister(intptr_t reg);
-  void StoreRegister(intptr_t reg, intptr_t value);
-  void StoreRegister(PushArgumentInstr* registers,
-                     PushArgumentInstr* index,
-                     PushArgumentInstr* value);
-
-  // Load a number of characters at the given offset from the
-  // current position, into the current-character register.
-  void LoadCurrentCharacterUnchecked(intptr_t cp_offset,
-                                     intptr_t character_count);
-
-  // Returns the character within the passed string at the specified index.
-  Value* CharacterAt(LocalVariable* index);
-
-  // Load a number of characters starting from index in the pattern string.
-  Value* LoadCodeUnitsAt(LocalVariable* index, intptr_t character_count);
-
-  // Check whether preemption has been requested.
-  void CheckPreemption();
-
-  // Byte size of chars in the string to match (decided by the Mode argument)
-  inline intptr_t char_size() { return static_cast<int>(mode_); }
-
-  // Equivalent to a conditional branch to the label, unless the label
-  // is NULL, in which case it is a conditional Backtrack.
-  void BranchOrBacktrack(ComparisonInstr* comparison,
-                         BlockLabel* true_successor);
-
-  // Set up all local variables and parameters.
-  void InitializeLocals();
-
-  // Allocates a new local, and returns the appropriate id for placing it
-  // on the stack.
-  intptr_t GetNextLocalIndex();
-
-  // We never have any copied parameters.
-  intptr_t num_copied_params() const {
-    return 0;
-  }
-
-  // Return the position register at the specified index, creating it if
-  // necessary. Note that the number of such registers can exceed the amount
-  // required by the number of output captures.
-  LocalVariable* position_register(intptr_t index);
-
-  void set_current_instruction(Instruction* instruction);
-
-  // The following functions are responsible for appending instructions
-  // to the current instruction in various ways. The most simple one
-  // is AppendInstruction, which simply appends an instruction and performs
-  // bookkeeping.
-  void AppendInstruction(Instruction* instruction);
-  // Similar to AppendInstruction, but closes the current block by
-  // setting current_instruction_ to NULL.
-  void CloseBlockWith(Instruction* instruction);
-  // Appends definition and allocates a temp index for the result.
-  Value* Bind(Definition* definition);
-  // Loads and binds a local variable.
-  Value* BindLoadLocal(const LocalVariable& local);
-
-  // Appends the definition.
-  void Do(Definition* definition);
-  // Closes the current block with a jump to the specified block.
-  void GoTo(JoinEntryInstr* to);
-
-  // Accessors for our local stack_.
-  void PushStack(Definition* definition);
-  Definition* PopStack();
-  Definition* PeekStack();
-  void CheckStackLimit();
-  void GrowStack();
-
-  // Prints the specified argument. Used for debugging.
-  void Print(PushArgumentInstr* argument);
-
-  // A utility class tracking ids of various objects such as blocks, temps, etc.
-  class IdAllocator : public ValueObject {
-   public:
-    IdAllocator() : next_id(0) { }
-
-    intptr_t Count() const { return next_id; }
-    intptr_t Alloc(intptr_t count = 1) {
-      ASSERT(count >= 0);
-      intptr_t current_id = next_id;
-      next_id += count;
-      return current_id;
-    }
-    void Dealloc(intptr_t count = 1) {
-      ASSERT(count <= next_id);
-      next_id -= count;
-    }
-
-   private:
-    intptr_t next_id;
-  };
-
-  // Which mode to generate code for (ASCII or UC16).
-  Mode mode_;
-
-  // Which specific string class to generate code for.
-  intptr_t specialization_cid_;
-
-  // Block entries used internally.
-  GraphEntryInstr* entry_block_;
-  JoinEntryInstr* start_block_;
-  JoinEntryInstr* success_block_;
-  JoinEntryInstr* exit_block_;
-
-  // Shared backtracking block.
-  JoinEntryInstr* backtrack_block_;
-  // Single indirect goto instruction which performs all backtracking.
-  IndirectGotoInstr* backtrack_goto_;
-
-  const ParsedFunction* parsed_function_;
-  const ZoneGrowableArray<const ICData*>& ic_data_array_;
-
-  // All created blocks are contained within this set. Used for printing
-  // the generated code.
-  GrowableArray<BlockEntryInstr*> blocks_;
-
-  // The current instruction to link to when new code is emitted.
-  Instruction* current_instruction_;
-
-  // A list, acting as the runtime stack for both backtrack locations and
-  // stored positions within the string.
-  LocalVariable* stack_;
-  LocalVariable* stack_pointer_;
-
-  // Stores the current character within the string.
-  LocalVariable* current_character_;
-
-  // Stores the current location within the string as a negative offset
-  // from the end of the string.
-  LocalVariable* current_position_;
-
-  // The string being processed, passed as a function parameter.
-  LocalVariable* string_param_;
-
-  // Stores the length of string_param_.
-  LocalVariable* string_param_length_;
-
-  // The start index within the string, passed as a function parameter.
-  LocalVariable* start_index_param_;
-
-  // An assortment of utility variables.
-  LocalVariable* capture_length_;
-  LocalVariable* match_start_index_;
-  LocalVariable* capture_start_index_;
-  LocalVariable* match_end_index_;
-  LocalVariable* char_in_capture_;
-  LocalVariable* char_in_match_;
-  LocalVariable* index_temp_;
-
-  LocalVariable* result_;
-
-  // Stored positions containing group bounds. Generated as needed.
-  LocalVariable* registers_;
-  intptr_t registers_count_;
-  const intptr_t saved_registers_count_;
-
-  // The actual array objects used for the stack and registers.
-  Array& stack_array_cell_;
-  TypedData& registers_array_;
-
-  IdAllocator block_id_;
-  IdAllocator temp_id_;
-  IdAllocator arg_id_;
-  IdAllocator local_id_;
-  IdAllocator indirect_id_;
-};
-
-
 }  // namespace dart
 
 #endif  // VM_REGEXP_ASSEMBLER_H_