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Diffstat (limited to 'js/src/irregexp/imported/regexp-macro-assembler.h')
| -rw-r--r-- | js/src/irregexp/imported/regexp-macro-assembler.h | 361 |
1 files changed, 361 insertions, 0 deletions
diff --git a/js/src/irregexp/imported/regexp-macro-assembler.h b/js/src/irregexp/imported/regexp-macro-assembler.h new file mode 100644 index 0000000000..651f6cb580 --- /dev/null +++ b/js/src/irregexp/imported/regexp-macro-assembler.h @@ -0,0 +1,361 @@ +// 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 "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; + +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; + static constexpr int kMaxCPOffset = (1 << 15) - 1; + static constexpr int kMinCPOffset = -(1 << 15); + + static constexpr int kTableSizeBits = 7; + static constexpr int kTableSize = 1 << kTableSizeBits; + static constexpr int kTableMask = kTableSize - 1; + + static constexpr int kUseCharactersValue = -1; + + RegExpMacroAssembler(Isolate* isolate, Zone* zone); + virtual ~RegExpMacroAssembler() = default; + + virtual Handle<HeapObject> GetCode(Handle<String> source) = 0; + + // 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. + virtual int stack_limit_slack() = 0; + virtual bool CanReadUnaligned() const = 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; + // 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 CheckGreedyLoop(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<CharacterRange>* ranges, Label* on_in_range) = 0; + virtual bool CheckCharacterNotInRangeArray( + const ZoneList<CharacterRange>* 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<ByteArray> 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); + // 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 CheckSpecialClassRanges(StandardCharacterSet type, + Label* on_no_match) { + return false; + } + + // 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 StackCheckFlag { 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; + + // Check that we are not in the middle of a surrogate pair. + void CheckNotInSurrogatePair(int cp_offset, 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, + Isolate* isolate); + + // Controls the generation of large inlined constants in the code. + void set_slow_safe(bool ssc) { slow_safe_compiler_ = ssc; } + bool slow_safe() const { return slow_safe_compiler_; } + + // 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). + 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. + 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 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; } + + Isolate* isolate() const { return isolate_; } + Zone* zone() const { return zone_; } + + protected: + bool has_backtrack_limit() const; + uint32_t backtrack_limit() const { return backtrack_limit_; } + + bool can_fallback() const { return can_fallback_; } + + private: + bool slow_safe_compiler_; + uint32_t backtrack_limit_; + bool can_fallback_ = false; + GlobalMode global_mode_; + Isolate* const isolate_; + Zone* const zone_; +}; + +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. + // 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) + : RegExpMacroAssembler(isolate, zone), range_array_cache_(zone) {} + ~NativeRegExpMacroAssembler() override = default; + + // Returns a {Result} sentinel, or the number of successful matches. + static int Match(Handle<JSRegExp> regexp, Handle<String> subject, + int* offsets_vector, int offsets_vector_length, + int previous_index, Isolate* isolate); + + V8_EXPORT_PRIVATE static int ExecuteForTesting(String input, int start_offset, + const byte* input_start, + const byte* input_end, + int* output, int output_size, + Isolate* isolate, + JSRegExp regexp); + + bool CanReadUnaligned() const override; + + 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, + InstructionStream re_code, Address* subject, + const byte** input_start, + const byte** input_end); + + static Address word_character_map_address() { + return reinterpret_cast<Address>(&word_character_map[0]); + } + + protected: + // 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]; + + Handle<ByteArray> GetOrAddRangeArray(const ZoneList<CharacterRange>* ranges); + + private: + // Returns a {Result} sentinel, or the number of successful matches. + static int Execute(String input, int start_offset, const byte* input_start, + const byte* input_end, int* output, int output_size, + Isolate* isolate, JSRegExp regexp); + + ZoneUnorderedMap<uint32_t, Handle<FixedUInt16Array>> range_array_cache_; +}; + +} // namespace internal +} // namespace v8 + +#endif // V8_REGEXP_REGEXP_MACRO_ASSEMBLER_H_ |