// 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_REGEXP_MACRO_ASSEMBLER_H_ #define V8_REGEXP_REGEXP_MACRO_ASSEMBLER_H_ #include #include "irregexp/imported/regexp-ast.h" #include "irregexp/imported/regexp.h" #include "irregexp/RegExpShim.h" namespace v8 { namespace internal { class ByteArray; class JSRegExp; class Label; class String; namespace regexp { static const base::uc32 kLeadSurrogateStart = 0xd800; static const base::uc32 kLeadSurrogateEnd = 0xdbff; static const base::uc32 kTrailSurrogateStart = 0xdc00; static const base::uc32 kTrailSurrogateEnd = 0xdfff; static const base::uc32 kNonBmpStart = 0x10000; static const base::uc32 kNonBmpEnd = 0x10ffff; class RegExpMacroAssembler { public: // The implementation must be able to handle at least: static constexpr int kMaxRegisterCount = (1 << 16); static constexpr int kMaxRegister = kMaxRegisterCount - 1; static constexpr int kMaxCaptures = (kMaxRegister - 1) / 2; // Note the minimum value is chosen s.t. a negated valid offset is also a // valid offset. static constexpr int kMaxCPOffset = (1 << 15) - 1; static constexpr int kMinCPOffset = -kMaxCPOffset; static constexpr int kTableSizeBits = 7; static constexpr int kTableSize = 1 << kTableSizeBits; static constexpr int kTableMask = kTableSize - 1; static constexpr int kUseCharactersValue = -1; // Type of input string to generate code for. enum Mode { LATIN1 = 1, UC16 = 2 }; RegExpMacroAssembler(Isolate* isolate, Zone* zone, Mode mode); RegExpMacroAssembler(const RegExpMacroAssembler& other) V8_NOEXCEPT = default; virtual ~RegExpMacroAssembler() = default; virtual DirectHandle GetCode(DirectHandle re_data, Flags flags) = 0; void LogCode(Isolate* isolate, DirectHandle code, DirectHandle re_data, Flags flags); // This function is called when code generation is aborted, so that // the assembler could clean up internal data structures. virtual void AbortedCodeGeneration() {} // 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. int stack_limit_slack_slot_count() const; bool CanReadUnaligned() const; 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; // 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(base::uc16 limit, Label* on_greater) = 0; virtual void CheckCharacterLT(base::uc16 limit, Label* on_less) = 0; virtual void CheckFixedLengthLoop(Label* on_tos_equals_current_position) = 0; virtual void CheckAtStart(int cp_offset, Label* on_at_start) = 0; virtual void CheckNotAtStart(int cp_offset, Label* on_not_at_start) = 0; virtual void CheckNotBackReference(int start_reg, bool read_backward, Label* on_no_match) = 0; virtual void CheckNotBackReferenceIgnoreCase(int start_reg, bool read_backward, bool unicode, 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 nullptr 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(base::uc16 c, base::uc16 minus, base::uc16 and_with, Label* on_not_equal) = 0; virtual void CheckCharacterInRange(base::uc16 from, base::uc16 to, // Both inclusive. Label* on_in_range) = 0; virtual void CheckCharacterNotInRange(base::uc16 from, base::uc16 to, // Both inclusive. Label* on_not_in_range) = 0; // Returns true if the check was emitted, false otherwise. virtual bool CheckCharacterInRangeArray( const ZoneList* ranges, Label* on_in_range) = 0; virtual bool CheckCharacterNotInRangeArray( const ZoneList* ranges, 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; virtual void SkipUntilBitInTable(int cp_offset, Handle table, Handle nibble_table, int advance_by, Label* on_match, Label* on_no_match) = 0; virtual bool SkipUntilBitInTableUseSimd(int advance_by) { return false; } virtual void SkipUntilCharAnd(int cp_offset, int advance_by, unsigned character, unsigned mask, int eats_at_least, Label* on_match, Label* on_no_match); virtual void SkipUntilChar(int cp_offset, int advance_by, unsigned character, Label* on_match, Label* on_no_match); virtual void SkipUntilCharPosChecked(int cp_offset, int advance_by, unsigned character, int eats_at_least, Label* on_match, Label* on_no_match); virtual void SkipUntilCharOrChar(int cp_offset, int advance_by, unsigned char1, unsigned char2, Label* on_match, Label* on_no_match); virtual void SkipUntilGtOrNotBitInTable(int cp_offset, int advance_by, unsigned character, Handle table, Label* on_match, Label* on_no_match); virtual void SkipUntilOneOfMasked(int cp_offset, int advance_by, unsigned both_chars, unsigned both_mask, int max_offset, unsigned chars1, unsigned mask1, unsigned chars2, unsigned mask2, Label* on_match1, Label* on_match2, Label* on_failure); struct SkipUntilOneOfMasked3Args { int bc0_cp_offset; int bc0_advance_by; Handle bc0_table; Handle bc0_nibble_table; int bc1_cp_offset; Label* bc1_on_failure; int bc2_cp_offset; unsigned bc3_characters; unsigned bc3_mask; int bc4_by; int bc5_cp_offset; unsigned bc6_characters; unsigned bc6_mask; Label* bc6_on_equal; unsigned bc7_characters; unsigned bc7_mask; Label* bc7_on_equal; unsigned bc8_characters; unsigned bc8_mask; Label* fallthrough_jump_target; }; virtual bool SkipUntilOneOfMasked3UseSimd( const SkipUntilOneOfMasked3Args& args) { return false; } virtual void SkipUntilOneOfMasked3(const SkipUntilOneOfMasked3Args& args); // Checks whether the given offset from the current position is is in-bounds. // May overwrite the current character. virtual void CheckPosition(int cp_offset, Label* on_outside_input) = 0; // Check whether a special character class has custom support for more // optimized code. bool CanOptimizeSpecialClassRanges(StandardCharacterSet) const; // Check whether a standard/default character class matches the current // character. // May clobber the current loaded character. virtual void CheckSpecialClassRanges(StandardCharacterSet type, Label* on_no_match) = 0; // Control-flow integrity: // Define a jump target and bind a label. virtual void BindJumpTarget(Label* label) { Bind(label); } virtual void Fail() = 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 nullptr. 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 nullptr. 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; V8_EXPORT_PRIVATE void LoadCurrentCharacter( int cp_offset, Label* on_end_of_input, bool check_bounds = true, int characters = 1, int eats_at_least = kUseCharactersValue); virtual void LoadCurrentCharacterImpl(int cp_offset, Label* on_end_of_input, bool check_bounds, int characters, int eats_at_least) = 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; enum class StackCheckFlag : uint8_t { kNoStackLimitCheck = false, kCheckStackLimit = true }; 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; virtual void RecordComment(std::string_view comment) = 0; virtual MacroAssembler* masm() = 0; // Check that we are not in the middle of a surrogate pair. void CheckNotInSurrogatePair(int cp_offset, Label* on_failure); // Step forward by 1 character/code point in the unanchored search loop. void UnanchoredAdvance(bool unicode, Label* on_failure); #define IMPLEMENTATIONS_LIST(V) \ V(IA32) \ V(ARM) \ V(ARM64) \ V(MIPS) \ V(LOONG64) \ V(RISCV) \ V(RISCV32) \ V(S390) \ V(PPC) \ V(X64) \ V(Bytecode) enum IrregexpImplementation { #define V(Name) k##Name##Implementation, IMPLEMENTATIONS_LIST(V) #undef V }; inline const char* ImplementationToString(IrregexpImplementation impl) { static const char* const kNames[] = { #define V(Name) #Name, IMPLEMENTATIONS_LIST(V) #undef V }; return kNames[impl]; } #undef IMPLEMENTATIONS_LIST virtual IrregexpImplementation Implementation() = 0; // Compare two-byte strings case insensitively. // // Called from generated code. static int CaseInsensitiveCompareNonUnicode(Address byte_offset1, Address byte_offset2, size_t byte_length, Isolate* isolate); static int CaseInsensitiveCompareUnicode(Address byte_offset1, Address byte_offset2, size_t byte_length, Isolate* isolate); // `raw_byte_array` is a ByteArray containing a set of character ranges, // where ranges are encoded as uint16_t elements: // // [from0, to0, from1, to1, ..., fromN, toN], or // [from0, to0, from1, to1, ..., fromN] (open-ended last interval). // // fromN is inclusive, toN is exclusive. Returns zero if not in a range, // non-zero otherwise. // // Called from generated code. static uint32_t IsCharacterInRangeArray(uint32_t current_char, Address raw_byte_array); // Controls after how many backtracks irregexp should abort execution. If it // can fall back to the experimental engine (see `set_can_fallback`), it will // return the appropriate error code, otherwise it will return the number of // matches found so far (perhaps none). virtual void set_backtrack_limit(uint32_t backtrack_limit) { backtrack_limit_ = backtrack_limit; } // Set whether or not irregexp can fall back to the experimental engine on // excessive backtracking. The number of backtracks considered excessive can // be controlled with set_backtrack_limit. virtual void set_can_fallback(bool val) { can_fallback_ = val; } enum GlobalMode { NOT_GLOBAL, GLOBAL_NO_ZERO_LENGTH_CHECK, GLOBAL, GLOBAL_UNICODE }; // Set whether the regular expression has the global flag. Exiting due to // a failure in a global regexp may still mean success overall. inline virtual void set_global_mode(GlobalMode mode) { global_mode_ = mode; } inline bool global() const { return global_mode_ != NOT_GLOBAL; } inline bool global_with_zero_length_check() const { return global_mode_ == GLOBAL || global_mode_ == GLOBAL_UNICODE; } inline bool global_unicode() const { return global_mode_ == GLOBAL_UNICODE; } static Address word_character_map_address() { return reinterpret_cast
(&word_character_map_[0]); } static const base::Vector word_character_map() { return base::ArrayVector(word_character_map_); } Isolate* isolate() const { return isolate_; } Zone* zone() const { return zone_; } protected: // Byte size of chars in the string to match (decided by the Mode argument). inline int char_size() const { static_assert(static_cast(Mode::LATIN1) == sizeof(uint8_t)); static_assert(static_cast(Mode::UC16) == sizeof(uint16_t)); return static_cast(mode()); } bool has_backtrack_limit() const; uint32_t backtrack_limit() const { return backtrack_limit_; } bool can_fallback() const { return can_fallback_; } // Which mode to generate code for (LATIN1 or UC16). Mode mode() const { return mode_; } static constexpr size_t kWordCharacterMapSize = 256; // 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 uint8_t word_character_map_[kWordCharacterMapSize]; private: uint32_t backtrack_limit_; bool can_fallback_ = false; GlobalMode global_mode_; Isolate* const isolate_; Zone* const zone_; const Mode mode_; }; class NativeRegExpMacroAssembler : public RegExpMacroAssembler { public: // 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. // FALLBACK_TO_EXPERIMENTAL: Execute the regexp on this subject using the // experimental engine instead. enum Result { FAILURE = RegExp::kInternalRegExpFailure, SUCCESS = RegExp::kInternalRegExpSuccess, EXCEPTION = RegExp::kInternalRegExpException, RETRY = RegExp::kInternalRegExpRetry, FALLBACK_TO_EXPERIMENTAL = RegExp::kInternalRegExpFallbackToExperimental, SMALLEST_REGEXP_RESULT = RegExp::kInternalRegExpSmallestResult, }; NativeRegExpMacroAssembler(Isolate* isolate, Zone* zone, Mode mode) : RegExpMacroAssembler(isolate, zone, mode), range_array_cache_(zone) {} ~NativeRegExpMacroAssembler() override = default; // Returns a {Result} sentinel, or the number of successful matches. static int Match(DirectHandle regexp_data, DirectHandle subject, int* offsets_vector, int offsets_vector_length, int previous_index, Isolate* isolate); V8_EXPORT_PRIVATE static int ExecuteForTesting( Tagged input, int start_offset, const uint8_t* input_start, const uint8_t* input_end, int* output, int output_size, Isolate* isolate, Tagged regexp); void LoadCurrentCharacterImpl(int cp_offset, Label* on_end_of_input, bool check_bounds, int characters, int eats_at_least) override; // Load a number of characters at the given offset from the // current position, into the current-character register. virtual void LoadCurrentCharacterUnchecked(int cp_offset, int character_count) = 0; // Called from RegExp if the backtrack stack limit is hit. Tries to expand // the stack. Returns the new stack-pointer if successful, or returns 0 if // unable to grow the stack. // This function must not trigger a garbage collection. // // Called from generated code. static Address GrowStack(Isolate* isolate); // Called from generated code. static int CheckStackGuardState(Isolate* isolate, int start_index, RegExp::CallOrigin call_origin, Address* return_address, Tagged re_code, Address* subject, const uint8_t** input_start, const uint8_t** input_end, uintptr_t gap); protected: Handle GetOrAddRangeArray(const ZoneList* ranges); private: // Returns a {Result} sentinel, or the number of successful matches. static int Execute(Tagged input, int start_offset, const uint8_t* input_start, const uint8_t* input_end, int* output, int output_size, Isolate* isolate, Tagged regexp_data); ZoneUnorderedMap> range_array_cache_; }; } // namespace regexp } // namespace internal } // namespace v8 #endif // V8_REGEXP_REGEXP_MACRO_ASSEMBLER_H_