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Diffstat (limited to 'js/src/regexp/regexp-macro-assembler.h')
| -rw-r--r-- | js/src/regexp/regexp-macro-assembler.h | 277 |
1 files changed, 277 insertions, 0 deletions
diff --git a/js/src/regexp/regexp-macro-assembler.h b/js/src/regexp/regexp-macro-assembler.h new file mode 100644 index 0000000000..67d97d1228 --- /dev/null +++ b/js/src/regexp/regexp-macro-assembler.h @@ -0,0 +1,277 @@ +// 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 "regexp/regexp-ast.h" +#include "regexp/regexp.h" + +namespace v8 { +namespace internal { + +static const uc32 kLeadSurrogateStart = 0xd800; +static const uc32 kLeadSurrogateEnd = 0xdbff; +static const uc32 kTrailSurrogateStart = 0xdc00; +static const uc32 kTrailSurrogateEnd = 0xdfff; +static const uc32 kNonBmpStart = 0x10000; +static const uc32 kNonBmpEnd = 0x10ffff; + +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; + + static constexpr int kUseCharactersValue = -1; + + enum IrregexpImplementation { + kIA32Implementation, + kARMImplementation, + kARM64Implementation, + kMIPSImplementation, + kS390Implementation, + kPPCImplementation, + kX64Implementation, + kX87Implementation, + kBytecodeImplementation + }; + + enum StackCheckFlag { + kNoStackLimitCheck = false, + kCheckStackLimit = true + }; + + RegExpMacroAssembler(Isolate* isolate, Zone* zone); + virtual ~RegExpMacroAssembler(); + // 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() = 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(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 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(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<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 CheckSpecialCharacterClass(uc16 type, Label* on_no_match); + virtual void Fail() = 0; + virtual Handle<HeapObject> GetCode(Handle<String> 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 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; + virtual IrregexpImplementation Implementation() = 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; + 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; + + // 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); + + // Check that we are not in the middle of a surrogate pair. + void CheckNotInSurrogatePair(int cp_offset, Label* on_failure); + + // 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_; } + + void set_backtrack_limit(uint32_t backtrack_limit) { + backtrack_limit_ = backtrack_limit; + } + + 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() { return global_mode_ != NOT_GLOBAL; } + inline bool global_with_zero_length_check() { + return global_mode_ == GLOBAL || global_mode_ == GLOBAL_UNICODE; + } + inline bool global_unicode() { return global_mode_ == GLOBAL_UNICODE; } + + Isolate* isolate() const { return isolate_; } + Zone* zone() const { return zone_; } + + protected: + bool has_backtrack_limit() const { + return backtrack_limit_ != JSRegExp::kNoBacktrackLimit; + } + uint32_t backtrack_limit() const { return backtrack_limit_; } + + private: + bool slow_safe_compiler_; + uint32_t backtrack_limit_ = JSRegExp::kNoBacktrackLimit; + GlobalMode global_mode_; + Isolate* isolate_; + Zone* 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. + enum Result { + FAILURE = RegExp::kInternalRegExpFailure, + SUCCESS = RegExp::kInternalRegExpSuccess, + EXCEPTION = RegExp::kInternalRegExpException, + RETRY = RegExp::kInternalRegExpRetry, + }; + + NativeRegExpMacroAssembler(Isolate* isolate, Zone* zone); + ~NativeRegExpMacroAssembler() override; + bool CanReadUnaligned() override; + + // 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); + + // 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, const DisallowHeapAllocation& no_gc); + + static int CheckStackGuardState(Isolate* isolate, int start_index, + RegExp::CallOrigin call_origin, + Address* return_address, Code re_code, + Address* subject, const byte** input_start, + const byte** input_end); + + // 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 reinterpret_cast<Address>(&word_character_map[0]); + } + + // Returns a {Result} sentinel, or the number of successful matches. + V8_EXPORT_PRIVATE 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); +}; + +} // namespace internal +} // namespace v8 + +#endif // V8_REGEXP_REGEXP_MACRO_ASSEMBLER_H_ |