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// Copyright 2016 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_AST_H_
#define V8_REGEXP_REGEXP_AST_H_
#include <optional>
#include "irregexp/RegExpShim.h"
#ifdef V8_INTL_SUPPORT
#include "unicode/uniset.h"
#endif // V8_INTL_SUPPORT
namespace v8::internal {
#define FOR_EACH_REG_EXP_TREE_TYPE(VISIT) \
VISIT(Disjunction) \
VISIT(Alternative) \
VISIT(Assertion) \
VISIT(ClassRanges) \
VISIT(ClassSetOperand) \
VISIT(ClassSetExpression) \
VISIT(Atom) \
VISIT(Quantifier) \
VISIT(Capture) \
VISIT(Group) \
VISIT(Lookaround) \
VISIT(BackReference) \
VISIT(Empty) \
VISIT(Text)
#define FORWARD_DECLARE(Name) class RegExp##Name;
FOR_EACH_REG_EXP_TREE_TYPE(FORWARD_DECLARE)
#undef FORWARD_DECLARE
class RegExpCompiler;
class RegExpNode;
class RegExpTree;
class RegExpVisitor {
public:
virtual ~RegExpVisitor() = default;
#define MAKE_CASE(Name) \
virtual void* Visit##Name(RegExp##Name*, void* data) = 0;
FOR_EACH_REG_EXP_TREE_TYPE(MAKE_CASE)
#undef MAKE_CASE
};
// A simple closed interval.
class Interval {
public:
Interval() : from_(kNone), to_(kNone - 1) {} // '- 1' for branchless size().
Interval(int from, int to) : from_(from), to_(to) {}
Interval Union(Interval that) {
if (that.from_ == kNone) return *this;
if (from_ == kNone) return that;
return Interval(std::min(from_, that.from_), std::max(to_, that.to_));
}
static Interval Empty() { return Interval(); }
bool Contains(int value) const { return (from_ <= value) && (value <= to_); }
bool is_empty() const { return from_ == kNone; }
int from() const { return from_; }
int to() const { return to_; }
int size() const { return to_ - from_ + 1; }
static constexpr int kNone = -1;
private:
int from_;
int to_;
};
// Named standard character sets.
enum class StandardCharacterSet : char {
kWhitespace = 's', // Like /\s/.
kNotWhitespace = 'S', // Like /\S/.
kWord = 'w', // Like /\w/.
kNotWord = 'W', // Like /\W/.
kDigit = 'd', // Like /\d/.
kNotDigit = 'D', // Like /\D/.
kLineTerminator = 'n', // The inverse of /./.
kNotLineTerminator = '.', // Like /./.
kEverything = '*', // Matches every character, like /./s.
};
// Represents code points (with values up to 0x10FFFF) in the range from from_
// to to_, both ends are inclusive.
class CharacterRange {
public:
CharacterRange() = default;
// For compatibility with the CHECK_OK macro.
CharacterRange(void* null) { DCHECK_NULL(null); } // NOLINT
static inline CharacterRange Singleton(base::uc32 value) {
return CharacterRange(value, value);
}
static inline CharacterRange Range(base::uc32 from, base::uc32 to) {
DCHECK(0 <= from && to <= kMaxCodePoint);
DCHECK(static_cast<uint32_t>(from) <= static_cast<uint32_t>(to));
return CharacterRange(from, to);
}
static inline CharacterRange Everything() {
return CharacterRange(0, kMaxCodePoint);
}
static inline ZoneList<CharacterRange>* List(Zone* zone,
CharacterRange range) {
ZoneList<CharacterRange>* list =
zone->New<ZoneList<CharacterRange>>(1, zone);
list->Add(range, zone);
return list;
}
// Add class escapes. Add case equivalent closure for \w and \W if necessary.
V8_EXPORT_PRIVATE static void AddClassEscape(
StandardCharacterSet standard_character_set,
ZoneList<CharacterRange>* ranges, bool add_unicode_case_equivalents,
Zone* zone);
// Add case equivalents to ranges. Only used for /i, not for /ui or /vi, as
// the semantics for unicode mode are slightly different.
V8_EXPORT_PRIVATE static void AddCaseEquivalents(
Isolate* isolate, Zone* zone, ZoneList<CharacterRange>* ranges,
bool is_one_byte);
// Add case equivalent code points to ranges. Only used for /ui and /vi, not
// for /i, as the semantics for non-unicode mode are slightly different.
static void AddUnicodeCaseEquivalents(ZoneList<CharacterRange>* ranges,
Zone* zone);
bool Contains(base::uc32 i) const { return from_ <= i && i <= to_; }
base::uc32 from() const { return from_; }
base::uc32 to() const { return to_; }
bool IsEverything(base::uc32 max) const { return from_ == 0 && to_ >= max; }
bool IsSingleton() const { return from_ == to_; }
// Whether a range list is in canonical form: Ranges ordered by from value,
// and ranges non-overlapping and non-adjacent.
V8_EXPORT_PRIVATE static bool IsCanonical(
const ZoneList<CharacterRange>* ranges);
// Convert range list to canonical form. The characters covered by the ranges
// will still be the same, but no character is in more than one range, and
// adjacent ranges are merged. The resulting list may be shorter than the
// original, but cannot be longer.
static void Canonicalize(ZoneList<CharacterRange>* ranges);
// Negate the contents of a character range in canonical form.
static void Negate(const ZoneList<CharacterRange>* src,
ZoneList<CharacterRange>* dst, Zone* zone);
// Intersect the contents of two character ranges in canonical form.
static void Intersect(const ZoneList<CharacterRange>* lhs,
const ZoneList<CharacterRange>* rhs,
ZoneList<CharacterRange>* dst, Zone* zone);
// Subtract the contents of |to_remove| from the contents of |src|.
static void Subtract(const ZoneList<CharacterRange>* src,
const ZoneList<CharacterRange>* to_remove,
ZoneList<CharacterRange>* dst, Zone* zone);
// Remove all ranges outside the one-byte range.
static void ClampToOneByte(ZoneList<CharacterRange>* ranges);
// Checks if two ranges (both need to be canonical) are equal.
static bool Equals(const ZoneList<CharacterRange>* lhs,
const ZoneList<CharacterRange>* rhs);
private:
CharacterRange(base::uc32 from, base::uc32 to) : from_(from), to_(to) {}
static constexpr int kMaxCodePoint = 0x10ffff;
base::uc32 from_ = 0;
base::uc32 to_ = 0;
};
inline bool operator==(const CharacterRange& lhs, const CharacterRange& rhs) {
return lhs.from() == rhs.from() && lhs.to() == rhs.to();
}
inline bool operator!=(const CharacterRange& lhs, const CharacterRange& rhs) {
return !operator==(lhs, rhs);
}
#define DECL_BOILERPLATE(Name) \
void* Accept(RegExpVisitor* visitor, void* data) override; \
RegExpNode* ToNode(RegExpCompiler* compiler, RegExpNode* on_success) \
override; \
RegExp##Name* As##Name() override; \
bool Is##Name() override
class RegExpTree : public ZoneObject {
public:
static const int kInfinity = kMaxInt;
virtual ~RegExpTree() = default;
virtual void* Accept(RegExpVisitor* visitor, void* data) = 0;
virtual RegExpNode* ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) = 0;
virtual bool IsTextElement() { return false; }
virtual bool IsAnchoredAtStart() { return false; }
virtual bool IsAnchoredAtEnd() { return false; }
virtual int min_match() = 0;
virtual int max_match() = 0;
// Returns the interval of registers used for captures within this
// expression.
virtual Interval CaptureRegisters() { return Interval::Empty(); }
virtual void AppendToText(RegExpText* text, Zone* zone);
V8_EXPORT_PRIVATE std::ostream& Print(std::ostream& os, Zone* zone);
#define MAKE_ASTYPE(Name) \
virtual RegExp##Name* As##Name(); \
virtual bool Is##Name();
FOR_EACH_REG_EXP_TREE_TYPE(MAKE_ASTYPE)
#undef MAKE_ASTYPE
};
class RegExpDisjunction final : public RegExpTree {
public:
explicit RegExpDisjunction(ZoneList<RegExpTree*>* alternatives);
DECL_BOILERPLATE(Disjunction);
Interval CaptureRegisters() override;
bool IsAnchoredAtStart() override;
bool IsAnchoredAtEnd() override;
int min_match() override { return min_match_; }
int max_match() override { return max_match_; }
ZoneList<RegExpTree*>* alternatives() const { return alternatives_; }
private:
bool SortConsecutiveAtoms(RegExpCompiler* compiler);
void RationalizeConsecutiveAtoms(RegExpCompiler* compiler);
void FixSingleCharacterDisjunctions(RegExpCompiler* compiler);
ZoneList<RegExpTree*>* alternatives_;
int min_match_;
int max_match_;
};
class RegExpAlternative final : public RegExpTree {
public:
explicit RegExpAlternative(ZoneList<RegExpTree*>* nodes);
DECL_BOILERPLATE(Alternative);
Interval CaptureRegisters() override;
bool IsAnchoredAtStart() override;
bool IsAnchoredAtEnd() override;
int min_match() override { return min_match_; }
int max_match() override { return max_match_; }
ZoneList<RegExpTree*>* nodes() const { return nodes_; }
private:
ZoneList<RegExpTree*>* nodes_;
int min_match_;
int max_match_;
};
class RegExpAssertion final : public RegExpTree {
public:
enum class Type {
START_OF_LINE = 0,
START_OF_INPUT = 1,
END_OF_LINE = 2,
END_OF_INPUT = 3,
BOUNDARY = 4,
NON_BOUNDARY = 5,
LAST_ASSERTION_TYPE = NON_BOUNDARY,
};
explicit RegExpAssertion(Type type) : assertion_type_(type) {}
DECL_BOILERPLATE(Assertion);
bool IsAnchoredAtStart() override;
bool IsAnchoredAtEnd() override;
int min_match() override { return 0; }
int max_match() override { return 0; }
Type assertion_type() const { return assertion_type_; }
private:
const Type assertion_type_;
};
class CharacterSet final {
public:
explicit CharacterSet(StandardCharacterSet standard_set_type)
: standard_set_type_(standard_set_type) {}
explicit CharacterSet(ZoneList<CharacterRange>* ranges) : ranges_(ranges) {}
ZoneList<CharacterRange>* ranges(Zone* zone);
StandardCharacterSet standard_set_type() const {
return standard_set_type_.value();
}
void set_standard_set_type(StandardCharacterSet standard_set_type) {
standard_set_type_ = standard_set_type;
}
bool is_standard() const { return standard_set_type_.has_value(); }
V8_EXPORT_PRIVATE void Canonicalize();
private:
ZoneList<CharacterRange>* ranges_ = nullptr;
std::optional<StandardCharacterSet> standard_set_type_;
};
class RegExpClassRanges final : public RegExpTree {
public:
// NEGATED: The character class is negated and should match everything but
// the specified ranges.
// CONTAINS_SPLIT_SURROGATE: The character class contains part of a split
// surrogate and should not be unicode-desugared (crbug.com/641091).
// IS_CASE_FOLDED: If case folding is required (/i), it was already
// performed on individual ranges and should not be applied again.
enum Flag {
NEGATED = 1 << 0,
CONTAINS_SPLIT_SURROGATE = 1 << 1,
IS_CASE_FOLDED = 1 << 2,
};
using ClassRangesFlags = base::Flags<Flag>;
RegExpClassRanges(Zone* zone, ZoneList<CharacterRange>* ranges,
ClassRangesFlags class_ranges_flags = ClassRangesFlags())
: set_(ranges), class_ranges_flags_(class_ranges_flags) {
// Convert the empty set of ranges to the negated Everything() range.
if (ranges->is_empty()) {
ranges->Add(CharacterRange::Everything(), zone);
class_ranges_flags_ ^= NEGATED;
}
}
explicit RegExpClassRanges(StandardCharacterSet standard_set_type)
: set_(standard_set_type), class_ranges_flags_() {}
DECL_BOILERPLATE(ClassRanges);
bool IsTextElement() override { return true; }
int min_match() override { return 1; }
// The character class may match two code units for unicode regexps.
// TODO(yangguo): we should split this class for usage in TextElement, and
// make max_match() dependent on the character class content.
int max_match() override { return 2; }
void AppendToText(RegExpText* text, Zone* zone) override;
// TODO(lrn): Remove need for complex version if is_standard that
// recognizes a mangled standard set and just do { return set_.is_special(); }
bool is_standard(Zone* zone);
// Returns a value representing the standard character set if is_standard()
// returns true.
StandardCharacterSet standard_type() const {
return set_.standard_set_type();
}
CharacterSet character_set() const { return set_; }
ZoneList<CharacterRange>* ranges(Zone* zone) { return set_.ranges(zone); }
bool is_negated() const { return (class_ranges_flags_ & NEGATED) != 0; }
bool contains_split_surrogate() const {
return (class_ranges_flags_ & CONTAINS_SPLIT_SURROGATE) != 0;
}
bool is_case_folded() const {
return (class_ranges_flags_ & IS_CASE_FOLDED) != 0;
}
private:
CharacterSet set_;
ClassRangesFlags class_ranges_flags_;
};
struct CharacterClassStringLess {
bool operator()(base::Vector<const base::uc32> lhs,
base::Vector<const base::uc32> rhs) const {
// Longer strings first so we generate matches for the largest string
// possible.
if (lhs.length() != rhs.length()) {
return lhs.length() > rhs.length();
}
for (int i = 0; i < lhs.length(); i++) {
if (lhs[i] != rhs[i]) {
return lhs[i] < rhs[i];
}
}
return false;
}
};
// A type used for strings as part of character classes (only possible in
// unicode sets mode).
// We use a ZoneMap instead of an UnorderedZoneMap because we need to match
// the longest alternatives first. By using a ZoneMap with the custom comparator
// we can avoid sorting before assembling the code.
// Strings are likely short (the largest string in current unicode properties
// consists of 10 code points).
using CharacterClassStrings = ZoneMap<base::Vector<const base::uc32>,
RegExpTree*, CharacterClassStringLess>;
// TODO(pthier): If we are sure we don't want to use icu::UnicodeSets
// (performance evaluation pending), this class can be merged with
// RegExpClassRanges.
class RegExpClassSetOperand final : public RegExpTree {
public:
RegExpClassSetOperand(ZoneList<CharacterRange>* ranges,
CharacterClassStrings* strings);
DECL_BOILERPLATE(ClassSetOperand);
bool IsTextElement() override { return true; }
int min_match() override { return min_match_; }
int max_match() override { return max_match_; }
void Union(RegExpClassSetOperand* other, Zone* zone);
void Intersect(RegExpClassSetOperand* other,
ZoneList<CharacterRange>* temp_ranges, Zone* zone);
void Subtract(RegExpClassSetOperand* other,
ZoneList<CharacterRange>* temp_ranges, Zone* zone);
bool has_strings() const { return strings_ != nullptr && !strings_->empty(); }
ZoneList<CharacterRange>* ranges() { return ranges_; }
CharacterClassStrings* strings() {
DCHECK_NOT_NULL(strings_);
return strings_;
}
private:
ZoneList<CharacterRange>* ranges_;
CharacterClassStrings* strings_;
int min_match_;
int max_match_;
};
class RegExpClassSetExpression final : public RegExpTree {
public:
enum class OperationType { kUnion, kIntersection, kSubtraction };
RegExpClassSetExpression(OperationType op, bool is_negated,
bool may_contain_strings,
ZoneList<RegExpTree*>* operands);
DECL_BOILERPLATE(ClassSetExpression);
// Create an empty class set expression (matches everything if |is_negated|,
// nothing otherwise).
static RegExpClassSetExpression* Empty(Zone* zone, bool is_negated);
bool IsTextElement() override { return true; }
int min_match() override { return 0; }
int max_match() override { return max_match_; }
OperationType operation() const { return operation_; }
bool is_negated() const { return is_negated_; }
bool may_contain_strings() const { return may_contain_strings_; }
const ZoneList<RegExpTree*>* operands() const { return operands_; }
ZoneList<RegExpTree*>* operands() { return operands_; }
private:
// Recursively evaluates the tree rooted at |root|, computing the valid
// CharacterRanges and strings after applying all set operations.
// The original tree will be modified by this method, so don't store pointers
// to inner nodes of the tree somewhere else!
// Modifying the tree in-place saves memory and speeds up multiple calls of
// the method (e.g. when unrolling quantifiers).
// |temp_ranges| is used for intermediate results, passed as parameter to
// avoid allocating new lists all the time.
static RegExpClassSetOperand* ComputeExpression(
RegExpTree* root, ZoneList<CharacterRange>* temp_ranges, Zone* zone);
const OperationType operation_;
bool is_negated_;
const bool may_contain_strings_;
ZoneList<RegExpTree*>* operands_ = nullptr;
int max_match_;
};
class RegExpAtom final : public RegExpTree {
public:
explicit RegExpAtom(base::Vector<const base::uc16> data) : data_(data) {}
DECL_BOILERPLATE(Atom);
bool IsTextElement() override { return true; }
int min_match() override { return data_.length(); }
int max_match() override { return data_.length(); }
void AppendToText(RegExpText* text, Zone* zone) override;
base::Vector<const base::uc16> data() const { return data_; }
int length() const { return data_.length(); }
private:
base::Vector<const base::uc16> data_;
};
class TextElement final {
public:
enum TextType { ATOM, CLASS_RANGES };
static TextElement Atom(RegExpAtom* atom);
static TextElement ClassRanges(RegExpClassRanges* class_ranges);
int cp_offset() const { return cp_offset_; }
void set_cp_offset(int cp_offset) { cp_offset_ = cp_offset; }
int length() const;
TextType text_type() const { return text_type_; }
RegExpTree* tree() const { return tree_; }
RegExpAtom* atom() const {
DCHECK(text_type() == ATOM);
return reinterpret_cast<RegExpAtom*>(tree());
}
RegExpClassRanges* class_ranges() const {
DCHECK(text_type() == CLASS_RANGES);
return reinterpret_cast<RegExpClassRanges*>(tree());
}
private:
TextElement(TextType text_type, RegExpTree* tree)
: cp_offset_(-1), text_type_(text_type), tree_(tree) {}
int cp_offset_;
TextType text_type_;
RegExpTree* tree_;
};
class RegExpText final : public RegExpTree {
public:
explicit RegExpText(Zone* zone) : elements_(2, zone) {}
DECL_BOILERPLATE(Text);
bool IsTextElement() override { return true; }
int min_match() override { return length_; }
int max_match() override { return length_; }
void AppendToText(RegExpText* text, Zone* zone) override;
void AddElement(TextElement elm, Zone* zone) {
elements_.Add(elm, zone);
length_ += elm.length();
}
ZoneList<TextElement>* elements() { return &elements_; }
private:
ZoneList<TextElement> elements_;
int length_ = 0;
};
class RegExpQuantifier final : public RegExpTree {
public:
enum QuantifierType { GREEDY, NON_GREEDY, POSSESSIVE };
RegExpQuantifier(int min, int max, QuantifierType type, int index,
RegExpTree* body)
: body_(body),
min_(min),
max_(max),
quantifier_type_(type),
index_(index) {
if (min > 0 && body->min_match() > kInfinity / min) {
min_match_ = kInfinity;
} else {
min_match_ = min * body->min_match();
}
if (max > 0 && body->max_match() > kInfinity / max) {
max_match_ = kInfinity;
} else {
max_match_ = max * body->max_match();
}
}
DECL_BOILERPLATE(Quantifier);
static RegExpNode* ToNode(int min, int max, bool is_greedy, RegExpTree* body,
RegExpCompiler* compiler, RegExpNode* on_success,
bool not_at_start = false);
Interval CaptureRegisters() override;
int min_match() override { return min_match_; }
int max_match() override { return max_match_; }
int min() const { return min_; }
int max() const { return max_; }
QuantifierType quantifier_type() const { return quantifier_type_; }
int index() const { return index_; }
bool is_possessive() const { return quantifier_type_ == POSSESSIVE; }
bool is_non_greedy() const { return quantifier_type_ == NON_GREEDY; }
bool is_greedy() const { return quantifier_type_ == GREEDY; }
RegExpTree* body() const { return body_; }
private:
RegExpTree* body_;
int min_;
int max_;
int min_match_;
int max_match_;
QuantifierType quantifier_type_;
int index_;
};
class RegExpCapture final : public RegExpTree {
public:
explicit RegExpCapture(int index)
: body_(nullptr),
index_(index),
min_match_(0),
max_match_(0),
name_(nullptr) {}
DECL_BOILERPLATE(Capture);
static RegExpNode* ToNode(RegExpTree* body, int index,
RegExpCompiler* compiler, RegExpNode* on_success);
bool IsAnchoredAtStart() override;
bool IsAnchoredAtEnd() override;
Interval CaptureRegisters() override;
int min_match() override { return min_match_; }
int max_match() override { return max_match_; }
RegExpTree* body() { return body_; }
void set_body(RegExpTree* body) {
body_ = body;
min_match_ = body->min_match();
max_match_ = body->max_match();
}
int index() const { return index_; }
const ZoneVector<base::uc16>* name() const { return name_; }
void set_name(const ZoneVector<base::uc16>* name) { name_ = name; }
static int StartRegister(int index) { return index * 2; }
static int EndRegister(int index) { return index * 2 + 1; }
private:
RegExpTree* body_ = nullptr;
int index_;
int min_match_ = 0;
int max_match_ = 0;
const ZoneVector<base::uc16>* name_ = nullptr;
};
class RegExpGroup final : public RegExpTree {
public:
explicit RegExpGroup(RegExpTree* body, RegExpFlags flags)
: body_(body),
flags_(flags),
min_match_(body->min_match()),
max_match_(body->max_match()) {}
DECL_BOILERPLATE(Group);
bool IsAnchoredAtStart() override { return body_->IsAnchoredAtStart(); }
bool IsAnchoredAtEnd() override { return body_->IsAnchoredAtEnd(); }
int min_match() override { return min_match_; }
int max_match() override { return max_match_; }
Interval CaptureRegisters() override { return body_->CaptureRegisters(); }
RegExpTree* body() const { return body_; }
RegExpFlags flags() const { return flags_; }
private:
RegExpTree* body_;
const RegExpFlags flags_;
int min_match_;
int max_match_;
};
class RegExpLookaround final : public RegExpTree {
public:
enum Type { LOOKAHEAD, LOOKBEHIND };
RegExpLookaround(RegExpTree* body, bool is_positive, int capture_count,
int capture_from, Type type, int index)
: body_(body),
is_positive_(is_positive),
capture_count_(capture_count),
capture_from_(capture_from),
type_(type),
index_(index) {}
DECL_BOILERPLATE(Lookaround);
Interval CaptureRegisters() override;
bool IsAnchoredAtStart() override;
int min_match() override { return 0; }
int max_match() override { return 0; }
RegExpTree* body() const { return body_; }
bool is_positive() const { return is_positive_; }
int capture_count() const { return capture_count_; }
int capture_from() const { return capture_from_; }
Type type() const { return type_; }
int index() const { return index_; }
class Builder {
public:
Builder(bool is_positive, RegExpNode* on_success,
int stack_pointer_register, int position_register,
int capture_register_count = 0, int capture_register_start = 0);
RegExpNode* on_match_success() const { return on_match_success_; }
RegExpNode* ForMatch(RegExpNode* match);
private:
bool is_positive_;
RegExpNode* on_match_success_;
RegExpNode* on_success_;
int stack_pointer_register_;
int position_register_;
};
private:
RegExpTree* body_;
bool is_positive_;
int capture_count_;
int capture_from_;
Type type_;
int index_;
};
class RegExpBackReference final : public RegExpTree {
public:
explicit RegExpBackReference(Zone* zone) : captures_(1, zone) {}
explicit RegExpBackReference(RegExpCapture* capture, Zone* zone)
: captures_(1, zone) {
captures_.Add(capture, zone);
}
DECL_BOILERPLATE(BackReference);
int min_match() override { return 0; }
// The back reference may be recursive, e.g. /(\2)(\1)/. To avoid infinite
// recursion, we give up. Ignorance is bliss.
int max_match() override { return kInfinity; }
const ZoneList<RegExpCapture*>* captures() const { return &captures_; }
void add_capture(RegExpCapture* capture, Zone* zone) {
captures_.Add(capture, zone);
}
const ZoneVector<base::uc16>* name() const { return name_; }
void set_name(const ZoneVector<base::uc16>* name) { name_ = name; }
private:
ZoneList<RegExpCapture*> captures_;
const ZoneVector<base::uc16>* name_ = nullptr;
};
class RegExpEmpty final : public RegExpTree {
public:
DECL_BOILERPLATE(Empty);
int min_match() override { return 0; }
int max_match() override { return 0; }
};
} // namespace v8::internal
#undef DECL_BOILERPLATE
#endif // V8_REGEXP_REGEXP_AST_H_