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// 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_BYTECODE_GENERATOR_H_
#define V8_REGEXP_REGEXP_BYTECODE_GENERATOR_H_
#include "irregexp/imported/regexp-macro-assembler.h"
namespace v8 {
namespace internal {
// An assembler/generator for the Irregexp byte code.
class V8_EXPORT_PRIVATE RegExpBytecodeGenerator : public RegExpMacroAssembler {
public:
// Create an assembler. Instructions and relocation information are emitted
// into a buffer, with the instructions starting from the beginning and the
// relocation information starting from the end of the buffer. See CodeDesc
// for a detailed comment on the layout (globals.h).
//
// The assembler allocates and grows its own buffer, and buffer_size
// determines the initial buffer size. The buffer is owned by the assembler
// and deallocated upon destruction of the assembler.
RegExpBytecodeGenerator(Isolate* isolate, Zone* zone);
~RegExpBytecodeGenerator() override;
// The byte-code interpreter checks on each push anyway.
int stack_limit_slack() override { return 1; }
bool CanReadUnaligned() const override { return false; }
void Bind(Label* label) override;
void AdvanceCurrentPosition(int by) override; // Signed cp change.
void PopCurrentPosition() override;
void PushCurrentPosition() override;
void Backtrack() override;
void GoTo(Label* label) override;
void PushBacktrack(Label* label) override;
bool Succeed() override;
void Fail() override;
void PopRegister(int register_index) override;
void PushRegister(int register_index,
StackCheckFlag check_stack_limit) override;
void AdvanceRegister(int reg, int by) override; // r[reg] += by.
void SetCurrentPositionFromEnd(int by) override;
void SetRegister(int register_index, int to) override;
void WriteCurrentPositionToRegister(int reg, int cp_offset) override;
void ClearRegisters(int reg_from, int reg_to) override;
void ReadCurrentPositionFromRegister(int reg) override;
void WriteStackPointerToRegister(int reg) override;
void ReadStackPointerFromRegister(int reg) override;
void LoadCurrentCharacterImpl(int cp_offset, Label* on_end_of_input,
bool check_bounds, int characters,
int eats_at_least) override;
void CheckCharacter(unsigned c, Label* on_equal) override;
void CheckCharacterAfterAnd(unsigned c, unsigned mask,
Label* on_equal) override;
void CheckCharacterGT(base::uc16 limit, Label* on_greater) override;
void CheckCharacterLT(base::uc16 limit, Label* on_less) override;
void CheckGreedyLoop(Label* on_tos_equals_current_position) override;
void CheckAtStart(int cp_offset, Label* on_at_start) override;
void CheckNotAtStart(int cp_offset, Label* on_not_at_start) override;
void CheckNotCharacter(unsigned c, Label* on_not_equal) override;
void CheckNotCharacterAfterAnd(unsigned c, unsigned mask,
Label* on_not_equal) override;
void CheckNotCharacterAfterMinusAnd(base::uc16 c, base::uc16 minus,
base::uc16 mask,
Label* on_not_equal) override;
void CheckCharacterInRange(base::uc16 from, base::uc16 to,
Label* on_in_range) override;
void CheckCharacterNotInRange(base::uc16 from, base::uc16 to,
Label* on_not_in_range) override;
bool CheckCharacterInRangeArray(const ZoneList<CharacterRange>* ranges,
Label* on_in_range) override {
// Disabled in the interpreter, because 1) there is no constant pool that
// could store the ByteArray pointer, 2) bytecode size limits are not as
// restrictive as code (e.g. branch distances on arm), 3) bytecode for
// large character classes is already quite compact.
// TODO(jgruber): Consider using BytecodeArrays (with a constant pool)
// instead of plain ByteArrays; then we could implement
// CheckCharacterInRangeArray in the interpreter.
return false;
}
bool CheckCharacterNotInRangeArray(const ZoneList<CharacterRange>* ranges,
Label* on_not_in_range) override {
return false;
}
void CheckBitInTable(Handle<ByteArray> table, Label* on_bit_set) override;
void CheckNotBackReference(int start_reg, bool read_backward,
Label* on_no_match) override;
void CheckNotBackReferenceIgnoreCase(int start_reg, bool read_backward,
bool unicode,
Label* on_no_match) override;
void IfRegisterLT(int register_index, int comparand, Label* if_lt) override;
void IfRegisterGE(int register_index, int comparand, Label* if_ge) override;
void IfRegisterEqPos(int register_index, Label* if_eq) override;
IrregexpImplementation Implementation() override;
Handle<HeapObject> GetCode(Handle<String> source) override;
private:
void ExpandBuffer();
// Code and bitmap emission.
inline void EmitOrLink(Label* label);
inline void Emit32(uint32_t x);
inline void Emit16(uint32_t x);
inline void Emit8(uint32_t x);
inline void Emit(uint32_t bc, uint32_t arg);
inline void Emit(uint32_t bc, int32_t arg);
// Bytecode buffer.
int length();
void Copy(uint8_t* a);
// The buffer into which code and relocation info are generated.
static constexpr int kInitialBufferSize = 1024;
ZoneVector<uint8_t> buffer_;
// The program counter.
int pc_;
Label backtrack_;
int advance_current_start_;
int advance_current_offset_;
int advance_current_end_;
// Stores jump edges emitted for the bytecode (used by
// RegExpBytecodePeepholeOptimization).
// Key: jump source (offset in buffer_ where jump destination is stored).
// Value: jump destination (offset in buffer_ to jump to).
ZoneUnorderedMap<int, int> jump_edges_;
Isolate* isolate_;
static const int kInvalidPC = -1;
DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpBytecodeGenerator);
};
} // namespace internal
} // namespace v8
#endif // V8_REGEXP_REGEXP_BYTECODE_GENERATOR_H_