// Copyright 2012 the V8 project authors. All rights reserved. // Use of this source code is governed by a BSD-style license that can be // found in the LICENSE file. #ifndef V8_REGEXP_MACRO_ASSEMBLER_H_ #define V8_REGEXP_MACRO_ASSEMBLER_H_ #include "src/ast.h" namespace v8 { namespace internal { struct DisjunctDecisionRow { RegExpCharacterClass cc; Label* on_match; }; class RegExpMacroAssembler { public: // The implementation must be able to handle at least: static const int kMaxRegister = (1 << 16) - 1; static const int kMaxCPOffset = (1 << 15) - 1; static const int kMinCPOffset = -(1 << 15); static const int kTableSizeBits = 7; static const int kTableSize = 1 << kTableSizeBits; static const int kTableMask = kTableSize - 1; enum IrregexpImplementation { kIA32Implementation, kARMImplementation, kARM64Implementation, kMIPSImplementation, kPPCImplementation, kX64Implementation, kX87Implementation, kBytecodeImplementation }; enum StackCheckFlag { kNoStackLimitCheck = false, kCheckStackLimit = true }; RegExpMacroAssembler(Isolate* isolate, 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 int stack_limit_slack() = 0; virtual bool CanReadUnaligned() = 0; virtual void AdvanceCurrentPosition(int by) = 0; // Signed cp change. virtual void AdvanceRegister(int reg, int by) = 0; // r[reg] += by. // Continues execution from the position pushed on the top of the backtrack // stack by an earlier PushBacktrack(Label*). virtual void Backtrack() = 0; virtual void Bind(Label* label) = 0; virtual void CheckAtStart(Label* on_at_start) = 0; // Dispatch after looking the current character up in a 2-bits-per-entry // map. The destinations vector has up to 4 labels. virtual void CheckCharacter(unsigned c, Label* on_equal) = 0; // Bitwise and the current character with the given constant and then // check for a match with c. virtual void CheckCharacterAfterAnd(unsigned c, unsigned and_with, Label* on_equal) = 0; virtual void CheckCharacterGT(uc16 limit, Label* on_greater) = 0; virtual void CheckCharacterLT(uc16 limit, Label* on_less) = 0; virtual void CheckGreedyLoop(Label* on_tos_equals_current_position) = 0; virtual void CheckNotAtStart(Label* on_not_at_start) = 0; virtual void CheckNotBackReference(int start_reg, Label* on_no_match) = 0; virtual void CheckNotBackReferenceIgnoreCase(int start_reg, Label* on_no_match) = 0; // Check the current character for a match with a literal character. If we // fail to match then goto the on_failure label. End of input always // matches. If the label is NULL then we should pop a backtrack address off // the stack and go to that. virtual void CheckNotCharacter(unsigned c, Label* on_not_equal) = 0; virtual void CheckNotCharacterAfterAnd(unsigned c, unsigned and_with, Label* on_not_equal) = 0; // Subtract a constant from the current character, then and with the given // constant and then check for a match with c. virtual void CheckNotCharacterAfterMinusAnd(uc16 c, uc16 minus, uc16 and_with, Label* on_not_equal) = 0; virtual void CheckCharacterInRange(uc16 from, uc16 to, // Both inclusive. Label* on_in_range) = 0; virtual void CheckCharacterNotInRange(uc16 from, uc16 to, // Both inclusive. Label* on_not_in_range) = 0; // The current character (modulus the kTableSize) is looked up in the byte // array, and if the found byte is non-zero, we jump to the on_bit_set label. virtual void CheckBitInTable(Handle table, Label* on_bit_set) = 0; // Checks whether the given offset from the current position is before // the end of the string. May overwrite the current character. virtual void CheckPosition(int cp_offset, Label* on_outside_input) { LoadCurrentCharacter(cp_offset, on_outside_input, true); } // Check whether a standard/default character class matches the current // character. Returns false if the type of special character class does // not have custom support. // May clobber the current loaded character. virtual bool CheckSpecialCharacterClass(uc16 type, Label* on_no_match) { return false; } virtual void Fail() = 0; virtual Handle GetCode(Handle source) = 0; virtual void GoTo(Label* label) = 0; // Check whether a register is >= a given constant and go to a label if it // is. Backtracks instead if the label is NULL. virtual void IfRegisterGE(int reg, int comparand, Label* if_ge) = 0; // Check whether a register is < a given constant and go to a label if it is. // Backtracks instead if the label is NULL. virtual void IfRegisterLT(int reg, int comparand, Label* if_lt) = 0; // Check whether a register is == to the current position and go to a // label if it is. virtual void IfRegisterEqPos(int reg, Label* if_eq) = 0; virtual IrregexpImplementation Implementation() = 0; virtual void LoadCurrentCharacter(int cp_offset, Label* on_end_of_input, bool check_bounds = true, int characters = 1) = 0; virtual void PopCurrentPosition() = 0; virtual void PopRegister(int register_index) = 0; // Pushes the label on the backtrack stack, so that a following Backtrack // will go to this label. Always checks the backtrack stack limit. virtual void PushBacktrack(Label* label) = 0; virtual void PushCurrentPosition() = 0; virtual void PushRegister(int register_index, StackCheckFlag check_stack_limit) = 0; virtual void ReadCurrentPositionFromRegister(int reg) = 0; virtual void ReadStackPointerFromRegister(int reg) = 0; virtual void SetCurrentPositionFromEnd(int by) = 0; virtual void SetRegister(int register_index, int to) = 0; // Return whether the matching (with a global regexp) will be restarted. virtual bool Succeed() = 0; virtual void WriteCurrentPositionToRegister(int reg, int cp_offset) = 0; virtual void ClearRegisters(int reg_from, int reg_to) = 0; virtual void WriteStackPointerToRegister(int reg) = 0; // Controls the generation of large inlined constants in the code. void set_slow_safe(bool ssc) { slow_safe_compiler_ = ssc; } bool slow_safe() { return slow_safe_compiler_; } enum GlobalMode { NOT_GLOBAL, GLOBAL, GLOBAL_NO_ZERO_LENGTH_CHECK }; // Set whether the regular expression has the global flag. Exiting due to // a failure in a global regexp may still mean success overall. inline void set_global_mode(GlobalMode mode) { global_mode_ = mode; } inline bool global() { return global_mode_ != NOT_GLOBAL; } inline bool global_with_zero_length_check() { return global_mode_ == GLOBAL; } Isolate* isolate() const { return isolate_; } Zone* zone() const { return zone_; } private: bool slow_safe_compiler_; bool global_mode_; Isolate* isolate_; Zone* zone_; }; #ifndef V8_INTERPRETED_REGEXP // Avoid compiling unused code. class NativeRegExpMacroAssembler: public RegExpMacroAssembler { public: // Type of input string to generate code for. enum Mode { LATIN1 = 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 }; NativeRegExpMacroAssembler(Isolate* isolate, Zone* zone); virtual ~NativeRegExpMacroAssembler(); virtual bool CanReadUnaligned(); static Result Match(Handle regexp, Handle subject, int* offsets_vector, int offsets_vector_length, int previous_index, Isolate* isolate); // Compares two-byte strings case insensitively. // Called from generated RegExp code. static int CaseInsensitiveCompareUC16(Address byte_offset1, Address byte_offset2, size_t byte_length, Isolate* isolate); // Called from RegExp if the backtrack stack limit is hit. // Tries to expand the stack. Returns the new stack-pointer if // successful, and updates the stack_top address, or returns 0 if unable // to grow the stack. // This function must not trigger a garbage collection. static Address GrowStack(Address stack_pointer, Address* stack_top, Isolate* isolate); static const byte* StringCharacterPosition(String* subject, int start_index); // 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. static const byte word_character_map[256]; static Address word_character_map_address() { return const_cast
(&word_character_map[0]); } static Result Execute(Code* code, String* input, int start_offset, const byte* input_start, const byte* input_end, int* output, int output_size, Isolate* isolate); }; #endif // V8_INTERPRETED_REGEXP } } // namespace v8::internal #endif // V8_REGEXP_MACRO_ASSEMBLER_H_