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Commit d61a558a authored by Jakob Gruber's avatar Jakob Gruber Committed by Commit Bot
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Reland "[regexp] Move AST-to-Node code to a dedicated file" 

This is a reland of 811bfbbc

Original change's description:
> [regexp] Move AST-to-Node code to a dedicated file
>
> Prior to this CL, jsregexp contains a bunch of things that are slightly
> related but would be cleaner in separate files, including: AST-to-Node
> transformations, the compiler implementation, and a debugging printer.
>
> This CL extracts AST-to-Node transformations.
>
> Bug: v8:9359
> Change-Id: I030cfca5c40cfd72e3a7abe2188e4654cfe2277c
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1655303
> Auto-Submit: Jakob Gruber <jgruber@chromium.org>
> Reviewed-by: Yang Guo <yangguo@chromium.org>
> Commit-Queue: Jakob Gruber <jgruber@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#62148}

Tbr: yangguo@chromium.org
Bug: v8:9359
Change-Id: I68a16086dc56c9a059547033ca8bc1e9de1080db
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1658568Reviewed-by: 's avatarJakob Gruber <jgruber@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62154}
parent a1462d9f
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BUILD.gn
View file @ d61a558a
...@@ -2683,6 +2683,8 @@ v8_source_set("v8_base_without_compiler") { ...@@ -2683,6 +2683,8 @@ v8_source_set("v8_base_without_compiler") {
"src/regexp/regexp-ast.cc", "src/regexp/regexp-ast.cc",
"src/regexp/regexp-ast.h", "src/regexp/regexp-ast.h",
"src/regexp/regexp-bytecodes.h", "src/regexp/regexp-bytecodes.h",
"src/regexp/regexp-compiler-tonode.cc",
"src/regexp/regexp-compiler.h",
"src/regexp/regexp-interpreter.cc", "src/regexp/regexp-interpreter.cc",
"src/regexp/regexp-interpreter.h", "src/regexp/regexp-interpreter.h",
"src/regexp/regexp-macro-assembler-arch.h", "src/regexp/regexp-macro-assembler-arch.h",
......
src/regexp/jsregexp.cc
View file @ d61a558a
...@@ -17,6 +17,7 @@ ...@@ -17,6 +17,7 @@
#include "src/heap/heap-inl.h" #include "src/heap/heap-inl.h"
#include "src/objects/elements.h" #include "src/objects/elements.h"
#include "src/regexp/jsregexp-inl.h" #include "src/regexp/jsregexp-inl.h"
#include "src/regexp/regexp-compiler.h"
#include "src/regexp/regexp-interpreter.h" #include "src/regexp/regexp-interpreter.h"
#include "src/regexp/regexp-macro-assembler-arch.h" #include "src/regexp/regexp-macro-assembler-arch.h"
#include "src/regexp/regexp-macro-assembler-irregexp.h" #include "src/regexp/regexp-macro-assembler-irregexp.h"
...@@ -40,6 +41,8 @@ ...@@ -40,6 +41,8 @@
namespace v8 { namespace v8 {
namespace internal { namespace internal {
using namespace regexp_compiler_constants; // NOLINT(build/namespaces)
V8_WARN_UNUSED_RESULT V8_WARN_UNUSED_RESULT
static inline MaybeHandle<Object> ThrowRegExpException( static inline MaybeHandle<Object> ThrowRegExpException(
Isolate* isolate, Handle<JSRegExp> re, Handle<String> pattern, Isolate* isolate, Handle<JSRegExp> re, Handle<String> pattern,
...@@ -844,149 +847,6 @@ DispatchTable* ChoiceNode::GetTable(bool ignore_case) { ...@@ -844,149 +847,6 @@ DispatchTable* ChoiceNode::GetTable(bool ignore_case) {
} }
class FrequencyCollator {
public:
FrequencyCollator() : total_samples_(0) {
for (int i = 0; i < RegExpMacroAssembler::kTableSize; i++) {
frequencies_[i] = CharacterFrequency(i);
}
}
void CountCharacter(int character) {
int index = (character & RegExpMacroAssembler::kTableMask);
frequencies_[index].Increment();
total_samples_++;
}
// Does not measure in percent, but rather per-128 (the table size from the
// regexp macro assembler).
int Frequency(int in_character) {
DCHECK((in_character & RegExpMacroAssembler::kTableMask) == in_character);
if (total_samples_ < 1) return 1; // Division by zero.
int freq_in_per128 =
(frequencies_[in_character].counter() * 128) / total_samples_;
return freq_in_per128;
}
private:
class CharacterFrequency {
public:
CharacterFrequency() : counter_(0), character_(-1) { }
explicit CharacterFrequency(int character)
: counter_(0), character_(character) { }
void Increment() { counter_++; }
int counter() { return counter_; }
int character() { return character_; }
private:
int counter_;
int character_;
};
private:
CharacterFrequency frequencies_[RegExpMacroAssembler::kTableSize];
int total_samples_;
};
class RegExpCompiler {
public:
RegExpCompiler(Isolate* isolate, Zone* zone, int capture_count,
bool is_one_byte);
int AllocateRegister() {
if (next_register_ >= RegExpMacroAssembler::kMaxRegister) {
reg_exp_too_big_ = true;
return next_register_;
}
return next_register_++;
}
// Lookarounds to match lone surrogates for unicode character class matches
// are never nested. We can therefore reuse registers.
int UnicodeLookaroundStackRegister() {
if (unicode_lookaround_stack_register_ == kNoRegister) {
unicode_lookaround_stack_register_ = AllocateRegister();
}
return unicode_lookaround_stack_register_;
}
int UnicodeLookaroundPositionRegister() {
if (unicode_lookaround_position_register_ == kNoRegister) {
unicode_lookaround_position_register_ = AllocateRegister();
}
return unicode_lookaround_position_register_;
}
RegExpEngine::CompilationResult Assemble(Isolate* isolate,
RegExpMacroAssembler* assembler,
RegExpNode* start, int capture_count,
Handle<String> pattern);
inline void AddWork(RegExpNode* node) {
if (!node->on_work_list() && !node->label()->is_bound()) {
node->set_on_work_list(true);
work_list_->push_back(node);
}
}
static const int kImplementationOffset = 0;
static const int kNumberOfRegistersOffset = 0;
static const int kCodeOffset = 1;
RegExpMacroAssembler* macro_assembler() { return macro_assembler_; }
EndNode* accept() { return accept_; }
static const int kMaxRecursion = 100;
inline int recursion_depth() { return recursion_depth_; }
inline void IncrementRecursionDepth() { recursion_depth_++; }
inline void DecrementRecursionDepth() { recursion_depth_--; }
void SetRegExpTooBig() { reg_exp_too_big_ = true; }
inline bool one_byte() { return one_byte_; }
inline bool optimize() { return optimize_; }
inline void set_optimize(bool value) { optimize_ = value; }
inline bool limiting_recursion() { return limiting_recursion_; }
inline void set_limiting_recursion(bool value) {
limiting_recursion_ = value;
}
bool read_backward() { return read_backward_; }
void set_read_backward(bool value) { read_backward_ = value; }
FrequencyCollator* frequency_collator() { return &frequency_collator_; }
int current_expansion_factor() { return current_expansion_factor_; }
void set_current_expansion_factor(int value) {
current_expansion_factor_ = value;
}
Isolate* isolate() const { return isolate_; }
Zone* zone() const { return zone_; }
static const int kNoRegister = -1;
private:
EndNode* accept_;
int next_register_;
int unicode_lookaround_stack_register_;
int unicode_lookaround_position_register_;
std::vector<RegExpNode*>* work_list_;
int recursion_depth_;
RegExpMacroAssembler* macro_assembler_;
bool one_byte_;
bool reg_exp_too_big_;
bool limiting_recursion_;
bool optimize_;
bool read_backward_;
int current_expansion_factor_;
FrequencyCollator frequency_collator_;
Isolate* isolate_;
Zone* zone_;
};
class RecursionCheck { class RecursionCheck {
public: public:
explicit RecursionCheck(RegExpCompiler* compiler) : compiler_(compiler) { explicit RecursionCheck(RegExpCompiler* compiler) : compiler_(compiler) {
...@@ -2700,13 +2560,6 @@ RegExpNode* SeqRegExpNode::FilterSuccessor(int depth) { ...@@ -2700,13 +2560,6 @@ RegExpNode* SeqRegExpNode::FilterSuccessor(int depth) {
return set_replacement(this); return set_replacement(this);
} }
// We need to check for the following characters: 0x39C 0x3BC 0x178.
static inline bool RangeContainsLatin1Equivalents(CharacterRange range) {
// TODO(dcarney): this could be a lot more efficient.
return range.Contains(0x039C) || range.Contains(0x03BC) ||
range.Contains(0x0178);
}
static bool RangesContainLatin1Equivalents(ZoneList<CharacterRange>* ranges) { static bool RangesContainLatin1Equivalents(ZoneList<CharacterRange>* ranges) {
for (int i = 0; i < ranges->length(); i++) { for (int i = 0; i < ranges->length(); i++) {
...@@ -3518,30 +3371,6 @@ class AlternativeGenerationList { ...@@ -3518,30 +3371,6 @@ class AlternativeGenerationList {
AlternativeGeneration a_few_alt_gens_[kAFew]; AlternativeGeneration a_few_alt_gens_[kAFew];
}; };
static const uc32 kRangeEndMarker = 0x110000;
// The '2' variant is has inclusive from and exclusive to.
// This covers \s as defined in ECMA-262 5.1, 15.10.2.12,
// which include WhiteSpace (7.2) or LineTerminator (7.3) values.
static const int kSpaceRanges[] = {
'\t', '\r' + 1, ' ', ' ' + 1, 0x00A0, 0x00A1, 0x1680,
0x1681, 0x2000, 0x200B, 0x2028, 0x202A, 0x202F, 0x2030,
0x205F, 0x2060, 0x3000, 0x3001, 0xFEFF, 0xFF00, kRangeEndMarker};
static const int kSpaceRangeCount = arraysize(kSpaceRanges);
static const int kWordRanges[] = {
'0', '9' + 1, 'A', 'Z' + 1, '_', '_' + 1, 'a', 'z' + 1, kRangeEndMarker};
static const int kWordRangeCount = arraysize(kWordRanges);
static const int kDigitRanges[] = {'0', '9' + 1, kRangeEndMarker};
static const int kDigitRangeCount = arraysize(kDigitRanges);
static const int kSurrogateRanges[] = {
kLeadSurrogateStart, kLeadSurrogateStart + 1, kRangeEndMarker};
static const int kSurrogateRangeCount = arraysize(kSurrogateRanges);
static const int kLineTerminatorRanges[] = {
0x000A, 0x000B, 0x000D, 0x000E, 0x2028, 0x202A, kRangeEndMarker};
static const int kLineTerminatorRangeCount = arraysize(kLineTerminatorRanges);
void BoyerMoorePositionInfo::Set(int character) { void BoyerMoorePositionInfo::Set(int character) {
SetInterval(Interval(character, character)); SetInterval(Interval(character, character));
} }
...@@ -4684,1530 +4513,6 @@ void RegExpEngine::DotPrint(const char* label, ...@@ -4684,1530 +4513,6 @@ void RegExpEngine::DotPrint(const char* label,
#endif // DEBUG #endif // DEBUG
// -------------------------------------------------------------------
// Tree to graph conversion
RegExpNode* RegExpAtom::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
ZoneList<TextElement>* elms =
new(compiler->zone()) ZoneList<TextElement>(1, compiler->zone());
elms->Add(TextElement::Atom(this), compiler->zone());
return new (compiler->zone())
TextNode(elms, compiler->read_backward(), on_success);
}
RegExpNode* RegExpText::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return new (compiler->zone())
TextNode(elements(), compiler->read_backward(), on_success);
}
static bool CompareInverseRanges(ZoneList<CharacterRange>* ranges,
const int* special_class,
int length) {
length--; // Remove final marker.
DCHECK_EQ(kRangeEndMarker, special_class[length]);
DCHECK_NE(0, ranges->length());
DCHECK_NE(0, length);
DCHECK_NE(0, special_class[0]);
if (ranges->length() != (length >> 1) + 1) {
return false;
}
CharacterRange range = ranges->at(0);
if (range.from() != 0) {
return false;
}
for (int i = 0; i < length; i += 2) {
if (special_class[i] != (range.to() + 1)) {
return false;
}
range = ranges->at((i >> 1) + 1);
if (special_class[i+1] != range.from()) {
return false;
}
}
if (range.to() != String::kMaxCodePoint) {
return false;
}
return true;
}
static bool CompareRanges(ZoneList<CharacterRange>* ranges,
const int* special_class,
int length) {
length--; // Remove final marker.
DCHECK_EQ(kRangeEndMarker, special_class[length]);
if (ranges->length() * 2 != length) {
return false;
}
for (int i = 0; i < length; i += 2) {
CharacterRange range = ranges->at(i >> 1);
if (range.from() != special_class[i] ||
range.to() != special_class[i + 1] - 1) {
return false;
}
}
return true;
}
bool RegExpCharacterClass::is_standard(Zone* zone) {
// TODO(lrn): Remove need for this function, by not throwing away information
// along the way.
if (is_negated()) {
return false;
}
if (set_.is_standard()) {
return true;
}
if (CompareRanges(set_.ranges(zone), kSpaceRanges, kSpaceRangeCount)) {
set_.set_standard_set_type('s');
return true;
}
if (CompareInverseRanges(set_.ranges(zone), kSpaceRanges, kSpaceRangeCount)) {
set_.set_standard_set_type('S');
return true;
}
if (CompareInverseRanges(set_.ranges(zone),
kLineTerminatorRanges,
kLineTerminatorRangeCount)) {
set_.set_standard_set_type('.');
return true;
}
if (CompareRanges(set_.ranges(zone),
kLineTerminatorRanges,
kLineTerminatorRangeCount)) {
set_.set_standard_set_type('n');
return true;
}
if (CompareRanges(set_.ranges(zone), kWordRanges, kWordRangeCount)) {
set_.set_standard_set_type('w');
return true;
}
if (CompareInverseRanges(set_.ranges(zone), kWordRanges, kWordRangeCount)) {
set_.set_standard_set_type('W');
return true;
}
return false;
}
UnicodeRangeSplitter::UnicodeRangeSplitter(Zone* zone,
ZoneList<CharacterRange>* base)
: zone_(zone),
table_(zone),
bmp_(nullptr),
lead_surrogates_(nullptr),
trail_surrogates_(nullptr),
non_bmp_(nullptr) {
// The unicode range splitter categorizes given character ranges into:
// - Code points from the BMP representable by one code unit.
// - Code points outside the BMP that need to be split into surrogate pairs.
// - Lone lead surrogates.
// - Lone trail surrogates.
// Lone surrogates are valid code points, even though no actual characters.
// They require special matching to make sure we do not split surrogate pairs.
// We use the dispatch table to accomplish this. The base range is split up
// by the table by the overlay ranges, and the Call callback is used to
// filter and collect ranges for each category.
for (int i = 0; i < base->length(); i++) {
table_.AddRange(base->at(i), kBase, zone_);
}
// Add overlay ranges.
table_.AddRange(CharacterRange::Range(0, kLeadSurrogateStart - 1),
kBmpCodePoints, zone_);
table_.AddRange(CharacterRange::Range(kLeadSurrogateStart, kLeadSurrogateEnd),
kLeadSurrogates, zone_);
table_.AddRange(
CharacterRange::Range(kTrailSurrogateStart, kTrailSurrogateEnd),
kTrailSurrogates, zone_);
table_.AddRange(
CharacterRange::Range(kTrailSurrogateEnd + 1, kNonBmpStart - 1),
kBmpCodePoints, zone_);
table_.AddRange(CharacterRange::Range(kNonBmpStart, kNonBmpEnd),
kNonBmpCodePoints, zone_);
table_.ForEach(this);
}
void UnicodeRangeSplitter::Call(uc32 from, DispatchTable::Entry entry) {
OutSet* outset = entry.out_set();
if (!outset->Get(kBase)) return;
ZoneList<CharacterRange>** target = nullptr;
if (outset->Get(kBmpCodePoints)) {
target = &bmp_;
} else if (outset->Get(kLeadSurrogates)) {
target = &lead_surrogates_;
} else if (outset->Get(kTrailSurrogates)) {
target = &trail_surrogates_;
} else {
DCHECK(outset->Get(kNonBmpCodePoints));
target = &non_bmp_;
}
if (*target == nullptr)
*target = new (zone_) ZoneList<CharacterRange>(2, zone_);
(*target)->Add(CharacterRange::Range(entry.from(), entry.to()), zone_);
}
void AddBmpCharacters(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success, UnicodeRangeSplitter* splitter) {
ZoneList<CharacterRange>* bmp = splitter->bmp();
if (bmp == nullptr) return;
JSRegExp::Flags default_flags = JSRegExp::Flags();
result->AddAlternative(GuardedAlternative(TextNode::CreateForCharacterRanges(
compiler->zone(), bmp, compiler->read_backward(), on_success,
default_flags)));
}
void AddNonBmpSurrogatePairs(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success,
UnicodeRangeSplitter* splitter) {
ZoneList<CharacterRange>* non_bmp = splitter->non_bmp();
if (non_bmp == nullptr) return;
DCHECK(!compiler->one_byte());
Zone* zone = compiler->zone();
JSRegExp::Flags default_flags = JSRegExp::Flags();
CharacterRange::Canonicalize(non_bmp);
for (int i = 0; i < non_bmp->length(); i++) {
// Match surrogate pair.
// E.g. [\u10005-\u11005] becomes
// \ud800[\udc05-\udfff]|
// [\ud801-\ud803][\udc00-\udfff]|
// \ud804[\udc00-\udc05]
uc32 from = non_bmp->at(i).from();
uc32 to = non_bmp->at(i).to();
uc16 from_l = unibrow::Utf16::LeadSurrogate(from);
uc16 from_t = unibrow::Utf16::TrailSurrogate(from);
uc16 to_l = unibrow::Utf16::LeadSurrogate(to);
uc16 to_t = unibrow::Utf16::TrailSurrogate(to);
if (from_l == to_l) {
// The lead surrogate is the same.
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Singleton(from_l),
CharacterRange::Range(from_t, to_t), compiler->read_backward(),
on_success, default_flags)));
} else {
if (from_t != kTrailSurrogateStart) {
// Add [from_l][from_t-\udfff]
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Singleton(from_l),
CharacterRange::Range(from_t, kTrailSurrogateEnd),
compiler->read_backward(), on_success, default_flags)));
from_l++;
}
if (to_t != kTrailSurrogateEnd) {
// Add [to_l][\udc00-to_t]
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Singleton(to_l),
CharacterRange::Range(kTrailSurrogateStart, to_t),
compiler->read_backward(), on_success, default_flags)));
to_l--;
}
if (from_l <= to_l) {
// Add [from_l-to_l][\udc00-\udfff]
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Range(from_l, to_l),
CharacterRange::Range(kTrailSurrogateStart, kTrailSurrogateEnd),
compiler->read_backward(), on_success, default_flags)));
}
}
}
}
RegExpNode* NegativeLookaroundAgainstReadDirectionAndMatch(
RegExpCompiler* compiler, ZoneList<CharacterRange>* lookbehind,
ZoneList<CharacterRange>* match, RegExpNode* on_success, bool read_backward,
JSRegExp::Flags flags) {
Zone* zone = compiler->zone();
RegExpNode* match_node = TextNode::CreateForCharacterRanges(
zone, match, read_backward, on_success, flags);
int stack_register = compiler->UnicodeLookaroundStackRegister();
int position_register = compiler->UnicodeLookaroundPositionRegister();
RegExpLookaround::Builder lookaround(false, match_node, stack_register,
position_register);
RegExpNode* negative_match = TextNode::CreateForCharacterRanges(
zone, lookbehind, !read_backward, lookaround.on_match_success(), flags);
return lookaround.ForMatch(negative_match);
}
RegExpNode* MatchAndNegativeLookaroundInReadDirection(
RegExpCompiler* compiler, ZoneList<CharacterRange>* match,
ZoneList<CharacterRange>* lookahead, RegExpNode* on_success,
bool read_backward, JSRegExp::Flags flags) {
Zone* zone = compiler->zone();
int stack_register = compiler->UnicodeLookaroundStackRegister();
int position_register = compiler->UnicodeLookaroundPositionRegister();
RegExpLookaround::Builder lookaround(false, on_success, stack_register,
position_register);
RegExpNode* negative_match = TextNode::CreateForCharacterRanges(
zone, lookahead, read_backward, lookaround.on_match_success(), flags);
return TextNode::CreateForCharacterRanges(
zone, match, read_backward, lookaround.ForMatch(negative_match), flags);
}
void AddLoneLeadSurrogates(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success,
UnicodeRangeSplitter* splitter) {
JSRegExp::Flags default_flags = JSRegExp::Flags();
ZoneList<CharacterRange>* lead_surrogates = splitter->lead_surrogates();
if (lead_surrogates == nullptr) return;
Zone* zone = compiler->zone();
// E.g. \ud801 becomes \ud801(?![\udc00-\udfff]).
ZoneList<CharacterRange>* trail_surrogates = CharacterRange::List(
zone, CharacterRange::Range(kTrailSurrogateStart, kTrailSurrogateEnd));
RegExpNode* match;
if (compiler->read_backward()) {
// Reading backward. Assert that reading forward, there is no trail
// surrogate, and then backward match the lead surrogate.
match = NegativeLookaroundAgainstReadDirectionAndMatch(
compiler, trail_surrogates, lead_surrogates, on_success, true,
default_flags);
} else {
// Reading forward. Forward match the lead surrogate and assert that
// no trail surrogate follows.
match = MatchAndNegativeLookaroundInReadDirection(
compiler, lead_surrogates, trail_surrogates, on_success, false,
default_flags);
}
result->AddAlternative(GuardedAlternative(match));
}
void AddLoneTrailSurrogates(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success,
UnicodeRangeSplitter* splitter) {
JSRegExp::Flags default_flags = JSRegExp::Flags();
ZoneList<CharacterRange>* trail_surrogates = splitter->trail_surrogates();
if (trail_surrogates == nullptr) return;
Zone* zone = compiler->zone();
// E.g. \udc01 becomes (?<![\ud800-\udbff])\udc01
ZoneList<CharacterRange>* lead_surrogates = CharacterRange::List(
zone, CharacterRange::Range(kLeadSurrogateStart, kLeadSurrogateEnd));
RegExpNode* match;
if (compiler->read_backward()) {
// Reading backward. Backward match the trail surrogate and assert that no
// lead surrogate precedes it.
match = MatchAndNegativeLookaroundInReadDirection(
compiler, trail_surrogates, lead_surrogates, on_success, true,
default_flags);
} else {
// Reading forward. Assert that reading backward, there is no lead
// surrogate, and then forward match the trail surrogate.
match = NegativeLookaroundAgainstReadDirectionAndMatch(
compiler, lead_surrogates, trail_surrogates, on_success, false,
default_flags);
}
result->AddAlternative(GuardedAlternative(match));
}
RegExpNode* UnanchoredAdvance(RegExpCompiler* compiler,
RegExpNode* on_success) {
// This implements ES2015 21.2.5.2.3, AdvanceStringIndex.
DCHECK(!compiler->read_backward());
Zone* zone = compiler->zone();
// Advance any character. If the character happens to be a lead surrogate and
// we advanced into the middle of a surrogate pair, it will work out, as
// nothing will match from there. We will have to advance again, consuming
// the associated trail surrogate.
ZoneList<CharacterRange>* range = CharacterRange::List(
zone, CharacterRange::Range(0, String::kMaxUtf16CodeUnit));
JSRegExp::Flags default_flags = JSRegExp::Flags();
return TextNode::CreateForCharacterRanges(zone, range, false, on_success,
default_flags);
}
void AddUnicodeCaseEquivalents(ZoneList<CharacterRange>* ranges, Zone* zone) {
#ifdef V8_INTL_SUPPORT
DCHECK(CharacterRange::IsCanonical(ranges));
// Micro-optimization to avoid passing large ranges to UnicodeSet::closeOver.
// See also https://crbug.com/v8/6727.
// TODO(jgruber): This only covers the special case of the {0,0x10FFFF} range,
// which we use frequently internally. But large ranges can also easily be
// created by the user. We might want to have a more general caching mechanism
// for such ranges.
if (ranges->length() == 1 && ranges->at(0).IsEverything(kNonBmpEnd)) return;
// Use ICU to compute the case fold closure over the ranges.
icu::UnicodeSet set;
for (int i = 0; i < ranges->length(); i++) {
set.add(ranges->at(i).from(), ranges->at(i).to());
}
ranges->Clear();
set.closeOver(USET_CASE_INSENSITIVE);
// Full case mapping map single characters to multiple characters.
// Those are represented as strings in the set. Remove them so that
// we end up with only simple and common case mappings.
set.removeAllStrings();
for (int i = 0; i < set.getRangeCount(); i++) {
ranges->Add(CharacterRange::Range(set.getRangeStart(i), set.getRangeEnd(i)),
zone);
}
// No errors and everything we collected have been ranges.
CharacterRange::Canonicalize(ranges);
#endif // V8_INTL_SUPPORT
}
RegExpNode* RegExpCharacterClass::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
set_.Canonicalize();
Zone* zone = compiler->zone();
ZoneList<CharacterRange>* ranges = this->ranges(zone);
if (NeedsUnicodeCaseEquivalents(flags_)) {
AddUnicodeCaseEquivalents(ranges, zone);
}
if (IsUnicode(flags_) && !compiler->one_byte() &&
!contains_split_surrogate()) {
if (is_negated()) {
ZoneList<CharacterRange>* negated =
new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::Negate(ranges, negated, zone);
ranges = negated;
}
if (ranges->length() == 0) {
JSRegExp::Flags default_flags;
RegExpCharacterClass* fail =
new (zone) RegExpCharacterClass(zone, ranges, default_flags);
return new (zone) TextNode(fail, compiler->read_backward(), on_success);
}
if (standard_type() == '*') {
return UnanchoredAdvance(compiler, on_success);
} else {
ChoiceNode* result = new (zone) ChoiceNode(2, zone);
UnicodeRangeSplitter splitter(zone, ranges);
AddBmpCharacters(compiler, result, on_success, &splitter);
AddNonBmpSurrogatePairs(compiler, result, on_success, &splitter);
AddLoneLeadSurrogates(compiler, result, on_success, &splitter);
AddLoneTrailSurrogates(compiler, result, on_success, &splitter);
return result;
}
} else {
return new (zone) TextNode(this, compiler->read_backward(), on_success);
}
}
int CompareFirstChar(RegExpTree* const* a, RegExpTree* const* b) {
RegExpAtom* atom1 = (*a)->AsAtom();
RegExpAtom* atom2 = (*b)->AsAtom();
uc16 character1 = atom1->data().at(0);
uc16 character2 = atom2->data().at(0);
if (character1 < character2) return -1;
if (character1 > character2) return 1;
return 0;
}
#ifdef V8_INTL_SUPPORT
// Case Insensitve comparesion
int CompareFirstCharCaseInsensitve(RegExpTree* const* a, RegExpTree* const* b) {
RegExpAtom* atom1 = (*a)->AsAtom();
RegExpAtom* atom2 = (*b)->AsAtom();
icu::UnicodeString character1(atom1->data().at(0));
return character1.caseCompare(atom2->data().at(0), U_FOLD_CASE_DEFAULT);
}
#else
static unibrow::uchar Canonical(
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize,
unibrow::uchar c) {
unibrow::uchar chars[unibrow::Ecma262Canonicalize::kMaxWidth];
int length = canonicalize->get(c, '\0', chars);
DCHECK_LE(length, 1);
unibrow::uchar canonical = c;
if (length == 1) canonical = chars[0];
return canonical;
}
int CompareFirstCharCaseIndependent(
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize,
RegExpTree* const* a, RegExpTree* const* b) {
RegExpAtom* atom1 = (*a)->AsAtom();
RegExpAtom* atom2 = (*b)->AsAtom();
unibrow::uchar character1 = atom1->data().at(0);
unibrow::uchar character2 = atom2->data().at(0);
if (character1 == character2) return 0;
if (character1 >= 'a' || character2 >= 'a') {
character1 = Canonical(canonicalize, character1);
character2 = Canonical(canonicalize, character2);
}
return static_cast<int>(character1) - static_cast<int>(character2);
}
#endif // V8_INTL_SUPPORT
// We can stable sort runs of atoms, since the order does not matter if they
// start with different characters.
// Returns true if any consecutive atoms were found.
bool RegExpDisjunction::SortConsecutiveAtoms(RegExpCompiler* compiler) {
ZoneList<RegExpTree*>* alternatives = this->alternatives();
int length = alternatives->length();
bool found_consecutive_atoms = false;
for (int i = 0; i < length; i++) {
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (alternative->IsAtom()) break;
i++;
}
// i is length or it is the index of an atom.
if (i == length) break;
int first_atom = i;
JSRegExp::Flags flags = alternatives->at(i)->AsAtom()->flags();
i++;
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (!alternative->IsAtom()) break;
if (alternative->AsAtom()->flags() != flags) break;
i++;
}
// Sort atoms to get ones with common prefixes together.
// This step is more tricky if we are in a case-independent regexp,
// because it would change /is|I/ to /I|is/, and order matters when
// the regexp parts don't match only disjoint starting points. To fix
// this we have a version of CompareFirstChar that uses case-
// independent character classes for comparison.
DCHECK_LT(first_atom, alternatives->length());
DCHECK_LE(i, alternatives->length());
DCHECK_LE(first_atom, i);
if (IgnoreCase(flags)) {
#ifdef V8_INTL_SUPPORT
alternatives->StableSort(CompareFirstCharCaseInsensitve, first_atom,
i - first_atom);
#else
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize =
compiler->isolate()->regexp_macro_assembler_canonicalize();
auto compare_closure =
[canonicalize](RegExpTree* const* a, RegExpTree* const* b) {
return CompareFirstCharCaseIndependent(canonicalize, a, b);
};
alternatives->StableSort(compare_closure, first_atom, i - first_atom);
#endif // V8_INTL_SUPPORT
} else {
alternatives->StableSort(CompareFirstChar, first_atom, i - first_atom);
}
if (i - first_atom > 1) found_consecutive_atoms = true;
}
return found_consecutive_atoms;
}
// Optimizes ab|ac|az to a(?:b|c|d).
void RegExpDisjunction::RationalizeConsecutiveAtoms(RegExpCompiler* compiler) {
Zone* zone = compiler->zone();
ZoneList<RegExpTree*>* alternatives = this->alternatives();
int length = alternatives->length();
int write_posn = 0;
int i = 0;
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (!alternative->IsAtom()) {
alternatives->at(write_posn++) = alternatives->at(i);
i++;
continue;
}
RegExpAtom* const atom = alternative->AsAtom();
JSRegExp::Flags flags = atom->flags();
#ifdef V8_INTL_SUPPORT
icu::UnicodeString common_prefix(atom->data().at(0));
#else
unibrow::uchar common_prefix = atom->data().at(0);
#endif // V8_INTL_SUPPORT
int first_with_prefix = i;
int prefix_length = atom->length();
i++;
while (i < length) {
alternative = alternatives->at(i);
if (!alternative->IsAtom()) break;
RegExpAtom* const atom = alternative->AsAtom();
if (atom->flags() != flags) break;
#ifdef V8_INTL_SUPPORT
icu::UnicodeString new_prefix(atom->data().at(0));
if (new_prefix != common_prefix) {
if (!IgnoreCase(flags)) break;
if (common_prefix.caseCompare(new_prefix, U_FOLD_CASE_DEFAULT) != 0)
break;
}
#else
unibrow::uchar new_prefix = atom->data().at(0);
if (new_prefix != common_prefix) {
if (!IgnoreCase(flags)) break;
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize =
compiler->isolate()->regexp_macro_assembler_canonicalize();
new_prefix = Canonical(canonicalize, new_prefix);
common_prefix = Canonical(canonicalize, common_prefix);
if (new_prefix != common_prefix) break;
}
#endif // V8_INTL_SUPPORT
prefix_length = Min(prefix_length, atom->length());
i++;
}
if (i > first_with_prefix + 2) {
// Found worthwhile run of alternatives with common prefix of at least one
// character. The sorting function above did not sort on more than one
// character for reasons of correctness, but there may still be a longer
// common prefix if the terms were similar or presorted in the input.
// Find out how long the common prefix is.
int run_length = i - first_with_prefix;
RegExpAtom* const atom = alternatives->at(first_with_prefix)->AsAtom();
for (int j = 1; j < run_length && prefix_length > 1; j++) {
RegExpAtom* old_atom =
alternatives->at(j + first_with_prefix)->AsAtom();
for (int k = 1; k < prefix_length; k++) {
if (atom->data().at(k) != old_atom->data().at(k)) {
prefix_length = k;
break;
}
}
}
RegExpAtom* prefix = new (zone)
RegExpAtom(atom->data().SubVector(0, prefix_length), flags);
ZoneList<RegExpTree*>* pair = new (zone) ZoneList<RegExpTree*>(2, zone);
pair->Add(prefix, zone);
ZoneList<RegExpTree*>* suffixes =
new (zone) ZoneList<RegExpTree*>(run_length, zone);
for (int j = 0; j < run_length; j++) {
RegExpAtom* old_atom =
alternatives->at(j + first_with_prefix)->AsAtom();
int len = old_atom->length();
if (len == prefix_length) {
suffixes->Add(new (zone) RegExpEmpty(), zone);
} else {
RegExpTree* suffix = new (zone) RegExpAtom(
old_atom->data().SubVector(prefix_length, old_atom->length()),
flags);
suffixes->Add(suffix, zone);
}
}
pair->Add(new (zone) RegExpDisjunction(suffixes), zone);
alternatives->at(write_posn++) = new (zone) RegExpAlternative(pair);
} else {
// Just copy any non-worthwhile alternatives.
for (int j = first_with_prefix; j < i; j++) {
alternatives->at(write_posn++) = alternatives->at(j);
}
}
}
alternatives->Rewind(write_posn); // Trim end of array.
}
// Optimizes b|c|z to [bcz].
void RegExpDisjunction::FixSingleCharacterDisjunctions(
RegExpCompiler* compiler) {
Zone* zone = compiler->zone();
ZoneList<RegExpTree*>* alternatives = this->alternatives();
int length = alternatives->length();
int write_posn = 0;
int i = 0;
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (!alternative->IsAtom()) {
alternatives->at(write_posn++) = alternatives->at(i);
i++;
continue;
}
RegExpAtom* const atom = alternative->AsAtom();
if (atom->length() != 1) {
alternatives->at(write_posn++) = alternatives->at(i);
i++;
continue;
}
JSRegExp::Flags flags = atom->flags();
DCHECK_IMPLIES(IsUnicode(flags),
!unibrow::Utf16::IsLeadSurrogate(atom->data().at(0)));
bool contains_trail_surrogate =
unibrow::Utf16::IsTrailSurrogate(atom->data().at(0));
int first_in_run = i;
i++;
// Find a run of single-character atom alternatives that have identical
// flags (case independence and unicode-ness).
while (i < length) {
alternative = alternatives->at(i);
if (!alternative->IsAtom()) break;
RegExpAtom* const atom = alternative->AsAtom();
if (atom->length() != 1) break;
if (atom->flags() != flags) break;
DCHECK_IMPLIES(IsUnicode(flags),
!unibrow::Utf16::IsLeadSurrogate(atom->data().at(0)));
contains_trail_surrogate |=
unibrow::Utf16::IsTrailSurrogate(atom->data().at(0));
i++;
}
if (i > first_in_run + 1) {
// Found non-trivial run of single-character alternatives.
int run_length = i - first_in_run;
ZoneList<CharacterRange>* ranges =
new (zone) ZoneList<CharacterRange>(2, zone);
for (int j = 0; j < run_length; j++) {
RegExpAtom* old_atom = alternatives->at(j + first_in_run)->AsAtom();
DCHECK_EQ(old_atom->length(), 1);
ranges->Add(CharacterRange::Singleton(old_atom->data().at(0)), zone);
}
RegExpCharacterClass::CharacterClassFlags character_class_flags;
if (IsUnicode(flags) && contains_trail_surrogate) {
character_class_flags = RegExpCharacterClass::CONTAINS_SPLIT_SURROGATE;
}
alternatives->at(write_posn++) = new (zone)
RegExpCharacterClass(zone, ranges, flags, character_class_flags);
} else {
// Just copy any trivial alternatives.
for (int j = first_in_run; j < i; j++) {
alternatives->at(write_posn++) = alternatives->at(j);
}
}
}
alternatives->Rewind(write_posn); // Trim end of array.
}
RegExpNode* RegExpDisjunction::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
ZoneList<RegExpTree*>* alternatives = this->alternatives();
if (alternatives->length() > 2) {
bool found_consecutive_atoms = SortConsecutiveAtoms(compiler);
if (found_consecutive_atoms) RationalizeConsecutiveAtoms(compiler);
FixSingleCharacterDisjunctions(compiler);
if (alternatives->length() == 1) {
return alternatives->at(0)->ToNode(compiler, on_success);
}
}
int length = alternatives->length();
ChoiceNode* result =
new(compiler->zone()) ChoiceNode(length, compiler->zone());
for (int i = 0; i < length; i++) {
GuardedAlternative alternative(alternatives->at(i)->ToNode(compiler,
on_success));
result->AddAlternative(alternative);
}
return result;
}
RegExpNode* RegExpQuantifier::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return ToNode(min(),
max(),
is_greedy(),
body(),
compiler,
on_success);
}
// Scoped object to keep track of how much we unroll quantifier loops in the
// regexp graph generator.
class RegExpExpansionLimiter {
public:
static const int kMaxExpansionFactor = 6;
RegExpExpansionLimiter(RegExpCompiler* compiler, int factor)
: compiler_(compiler),
saved_expansion_factor_(compiler->current_expansion_factor()),
ok_to_expand_(saved_expansion_factor_ <= kMaxExpansionFactor) {
DCHECK_LT(0, factor);
if (ok_to_expand_) {
if (factor > kMaxExpansionFactor) {
// Avoid integer overflow of the current expansion factor.
ok_to_expand_ = false;
compiler->set_current_expansion_factor(kMaxExpansionFactor + 1);
} else {
int new_factor = saved_expansion_factor_ * factor;
ok_to_expand_ = (new_factor <= kMaxExpansionFactor);
compiler->set_current_expansion_factor(new_factor);
}
}
}
~RegExpExpansionLimiter() {
compiler_->set_current_expansion_factor(saved_expansion_factor_);
}
bool ok_to_expand() { return ok_to_expand_; }
private:
RegExpCompiler* compiler_;
int saved_expansion_factor_;
bool ok_to_expand_;
DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpExpansionLimiter);
};
RegExpNode* RegExpQuantifier::ToNode(int min,
int max,
bool is_greedy,
RegExpTree* body,
RegExpCompiler* compiler,
RegExpNode* on_success,
bool not_at_start) {
// x{f, t} becomes this:
//
// (r++)<-.
// | `
// | (x)
// v ^
// (r=0)-->(?)---/ [if r < t]
// |
// [if r >= f] \----> ...
//
// 15.10.2.5 RepeatMatcher algorithm.
// The parser has already eliminated the case where max is 0. In the case
// where max_match is zero the parser has removed the quantifier if min was
// > 0 and removed the atom if min was 0. See AddQuantifierToAtom.
// If we know that we cannot match zero length then things are a little
// simpler since we don't need to make the special zero length match check
// from step 2.1. If the min and max are small we can unroll a little in
// this case.
static const int kMaxUnrolledMinMatches = 3; // Unroll (foo)+ and (foo){3,}
static const int kMaxUnrolledMaxMatches = 3; // Unroll (foo)? and (foo){x,3}
if (max == 0) return on_success; // This can happen due to recursion.
bool body_can_be_empty = (body->min_match() == 0);
int body_start_reg = RegExpCompiler::kNoRegister;
Interval capture_registers = body->CaptureRegisters();
bool needs_capture_clearing = !capture_registers.is_empty();
Zone* zone = compiler->zone();
if (body_can_be_empty) {
body_start_reg = compiler->AllocateRegister();
} else if (compiler->optimize() && !needs_capture_clearing) {
// Only unroll if there are no captures and the body can't be
// empty.
{
RegExpExpansionLimiter limiter(
compiler, min + ((max != min) ? 1 : 0));
if (min > 0 && min <= kMaxUnrolledMinMatches && limiter.ok_to_expand()) {
int new_max = (max == kInfinity) ? max : max - min;
// Recurse once to get the loop or optional matches after the fixed
// ones.
RegExpNode* answer = ToNode(
0, new_max, is_greedy, body, compiler, on_success, true);
// Unroll the forced matches from 0 to min. This can cause chains of
// TextNodes (which the parser does not generate). These should be
// combined if it turns out they hinder good code generation.
for (int i = 0; i < min; i++) {
answer = body->ToNode(compiler, answer);
}
return answer;
}
}
if (max <= kMaxUnrolledMaxMatches && min == 0) {
DCHECK_LT(0, max); // Due to the 'if' above.
RegExpExpansionLimiter limiter(compiler, max);
if (limiter.ok_to_expand()) {
// Unroll the optional matches up to max.
RegExpNode* answer = on_success;
for (int i = 0; i < max; i++) {
ChoiceNode* alternation = new(zone) ChoiceNode(2, zone);
if (is_greedy) {
alternation->AddAlternative(
GuardedAlternative(body->ToNode(compiler, answer)));
alternation->AddAlternative(GuardedAlternative(on_success));
} else {
alternation->AddAlternative(GuardedAlternative(on_success));
alternation->AddAlternative(
GuardedAlternative(body->ToNode(compiler, answer)));
}
answer = alternation;
if (not_at_start && !compiler->read_backward()) {
alternation->set_not_at_start();
}
}
return answer;
}
}
}
bool has_min = min > 0;
bool has_max = max < RegExpTree::kInfinity;
bool needs_counter = has_min || has_max;
int reg_ctr = needs_counter
? compiler->AllocateRegister()
: RegExpCompiler::kNoRegister;
LoopChoiceNode* center = new (zone)
LoopChoiceNode(body->min_match() == 0, compiler->read_backward(), zone);
if (not_at_start && !compiler->read_backward()) center->set_not_at_start();
RegExpNode* loop_return = needs_counter
? static_cast<RegExpNode*>(ActionNode::IncrementRegister(reg_ctr, center))
: static_cast<RegExpNode*>(center);
if (body_can_be_empty) {
// If the body can be empty we need to check if it was and then
// backtrack.
loop_return = ActionNode::EmptyMatchCheck(body_start_reg,
reg_ctr,
min,
loop_return);
}
RegExpNode* body_node = body->ToNode(compiler, loop_return);
if (body_can_be_empty) {
// If the body can be empty we need to store the start position
// so we can bail out if it was empty.
body_node = ActionNode::StorePosition(body_start_reg, false, body_node);
}
if (needs_capture_clearing) {
// Before entering the body of this loop we need to clear captures.
body_node = ActionNode::ClearCaptures(capture_registers, body_node);
}
GuardedAlternative body_alt(body_node);
if (has_max) {
Guard* body_guard =
new(zone) Guard(reg_ctr, Guard::LT, max);
body_alt.AddGuard(body_guard, zone);
}
GuardedAlternative rest_alt(on_success);
if (has_min) {
Guard* rest_guard = new(compiler->zone()) Guard(reg_ctr, Guard::GEQ, min);
rest_alt.AddGuard(rest_guard, zone);
}
if (is_greedy) {
center->AddLoopAlternative(body_alt);
center->AddContinueAlternative(rest_alt);
} else {
center->AddContinueAlternative(rest_alt);
center->AddLoopAlternative(body_alt);
}
if (needs_counter) {
return ActionNode::SetRegister(reg_ctr, 0, center);
} else {
return center;
}
}
namespace {
// Desugar \b to (?<=\w)(?=\W)|(?<=\W)(?=\w) and
// \B to (?<=\w)(?=\w)|(?<=\W)(?=\W)
RegExpNode* BoundaryAssertionAsLookaround(RegExpCompiler* compiler,
RegExpNode* on_success,
RegExpAssertion::AssertionType type,
JSRegExp::Flags flags) {
DCHECK(NeedsUnicodeCaseEquivalents(flags));
Zone* zone = compiler->zone();
ZoneList<CharacterRange>* word_range =
new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::AddClassEscape('w', word_range, true, zone);
int stack_register = compiler->UnicodeLookaroundStackRegister();
int position_register = compiler->UnicodeLookaroundPositionRegister();
ChoiceNode* result = new (zone) ChoiceNode(2, zone);
// Add two choices. The (non-)boundary could start with a word or
// a non-word-character.
for (int i = 0; i < 2; i++) {
bool lookbehind_for_word = i == 0;
bool lookahead_for_word =
(type == RegExpAssertion::BOUNDARY) ^ lookbehind_for_word;
// Look to the left.
RegExpLookaround::Builder lookbehind(lookbehind_for_word, on_success,
stack_register, position_register);
RegExpNode* backward = TextNode::CreateForCharacterRanges(
zone, word_range, true, lookbehind.on_match_success(), flags);
// Look to the right.
RegExpLookaround::Builder lookahead(lookahead_for_word,
lookbehind.ForMatch(backward),
stack_register, position_register);
RegExpNode* forward = TextNode::CreateForCharacterRanges(
zone, word_range, false, lookahead.on_match_success(), flags);
result->AddAlternative(GuardedAlternative(lookahead.ForMatch(forward)));
}
return result;
}
} // anonymous namespace
RegExpNode* RegExpAssertion::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
NodeInfo info;
Zone* zone = compiler->zone();
switch (assertion_type()) {
case START_OF_LINE:
return AssertionNode::AfterNewline(on_success);
case START_OF_INPUT:
return AssertionNode::AtStart(on_success);
case BOUNDARY:
return NeedsUnicodeCaseEquivalents(flags_)
? BoundaryAssertionAsLookaround(compiler, on_success, BOUNDARY,
flags_)
: AssertionNode::AtBoundary(on_success);
case NON_BOUNDARY:
return NeedsUnicodeCaseEquivalents(flags_)
? BoundaryAssertionAsLookaround(compiler, on_success,
NON_BOUNDARY, flags_)
: AssertionNode::AtNonBoundary(on_success);
case END_OF_INPUT:
return AssertionNode::AtEnd(on_success);
case END_OF_LINE: {
// Compile $ in multiline regexps as an alternation with a positive
// lookahead in one side and an end-of-input on the other side.
// We need two registers for the lookahead.
int stack_pointer_register = compiler->AllocateRegister();
int position_register = compiler->AllocateRegister();
// The ChoiceNode to distinguish between a newline and end-of-input.
ChoiceNode* result = new(zone) ChoiceNode(2, zone);
// Create a newline atom.
ZoneList<CharacterRange>* newline_ranges =
new(zone) ZoneList<CharacterRange>(3, zone);
CharacterRange::AddClassEscape('n', newline_ranges, false, zone);
JSRegExp::Flags default_flags = JSRegExp::Flags();
RegExpCharacterClass* newline_atom =
new (zone) RegExpCharacterClass('n', default_flags);
TextNode* newline_matcher = new (zone) TextNode(
newline_atom, false, ActionNode::PositiveSubmatchSuccess(
stack_pointer_register, position_register,
0, // No captures inside.
-1, // Ignored if no captures.
on_success));
// Create an end-of-input matcher.
RegExpNode* end_of_line = ActionNode::BeginSubmatch(
stack_pointer_register,
position_register,
newline_matcher);
// Add the two alternatives to the ChoiceNode.
GuardedAlternative eol_alternative(end_of_line);
result->AddAlternative(eol_alternative);
GuardedAlternative end_alternative(AssertionNode::AtEnd(on_success));
result->AddAlternative(end_alternative);
return result;
}
default:
UNREACHABLE();
}
return on_success;
}
RegExpNode* RegExpBackReference::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return new (compiler->zone())
BackReferenceNode(RegExpCapture::StartRegister(index()),
RegExpCapture::EndRegister(index()), flags_,
compiler->read_backward(), on_success);
}
RegExpNode* RegExpEmpty::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return on_success;
}
RegExpLookaround::Builder::Builder(bool is_positive, RegExpNode* on_success,
int stack_pointer_register,
int position_register,
int capture_register_count,
int capture_register_start)
: is_positive_(is_positive),
on_success_(on_success),
stack_pointer_register_(stack_pointer_register),
position_register_(position_register) {
if (is_positive_) {
on_match_success_ = ActionNode::PositiveSubmatchSuccess(
stack_pointer_register, position_register, capture_register_count,
capture_register_start, on_success_);
} else {
Zone* zone = on_success_->zone();
on_match_success_ = new (zone) NegativeSubmatchSuccess(
stack_pointer_register, position_register, capture_register_count,
capture_register_start, zone);
}
}
RegExpNode* RegExpLookaround::Builder::ForMatch(RegExpNode* match) {
if (is_positive_) {
return ActionNode::BeginSubmatch(stack_pointer_register_,
position_register_, match);
} else {
Zone* zone = on_success_->zone();
// We use a ChoiceNode to represent the negative lookaround. The first
// alternative is the negative match. On success, the end node backtracks.
// On failure, the second alternative is tried and leads to success.
// NegativeLookaheadChoiceNode is a special ChoiceNode that ignores the
// first exit when calculating quick checks.
ChoiceNode* choice_node = new (zone) NegativeLookaroundChoiceNode(
GuardedAlternative(match), GuardedAlternative(on_success_), zone);
return ActionNode::BeginSubmatch(stack_pointer_register_,
position_register_, choice_node);
}
}
RegExpNode* RegExpLookaround::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
int stack_pointer_register = compiler->AllocateRegister();
int position_register = compiler->AllocateRegister();
const int registers_per_capture = 2;
const int register_of_first_capture = 2;
int register_count = capture_count_ * registers_per_capture;
int register_start =
register_of_first_capture + capture_from_ * registers_per_capture;
RegExpNode* result;
bool was_reading_backward = compiler->read_backward();
compiler->set_read_backward(type() == LOOKBEHIND);
Builder builder(is_positive(), on_success, stack_pointer_register,
position_register, register_count, register_start);
RegExpNode* match = body_->ToNode(compiler, builder.on_match_success());
result = builder.ForMatch(match);
compiler->set_read_backward(was_reading_backward);
return result;
}
RegExpNode* RegExpCapture::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return ToNode(body(), index(), compiler, on_success);
}
RegExpNode* RegExpCapture::ToNode(RegExpTree* body,
int index,
RegExpCompiler* compiler,
RegExpNode* on_success) {
DCHECK_NOT_NULL(body);
int start_reg = RegExpCapture::StartRegister(index);
int end_reg = RegExpCapture::EndRegister(index);
if (compiler->read_backward()) std::swap(start_reg, end_reg);
RegExpNode* store_end = ActionNode::StorePosition(end_reg, true, on_success);
RegExpNode* body_node = body->ToNode(compiler, store_end);
return ActionNode::StorePosition(start_reg, true, body_node);
}
RegExpNode* RegExpAlternative::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
ZoneList<RegExpTree*>* children = nodes();
RegExpNode* current = on_success;
if (compiler->read_backward()) {
for (int i = 0; i < children->length(); i++) {
current = children->at(i)->ToNode(compiler, current);
}
} else {
for (int i = children->length() - 1; i >= 0; i--) {
current = children->at(i)->ToNode(compiler, current);
}
}
return current;
}
static void AddClass(const int* elmv,
int elmc,
ZoneList<CharacterRange>* ranges,
Zone* zone) {
elmc--;
DCHECK_EQ(kRangeEndMarker, elmv[elmc]);
for (int i = 0; i < elmc; i += 2) {
DCHECK(elmv[i] < elmv[i + 1]);
ranges->Add(CharacterRange::Range(elmv[i], elmv[i + 1] - 1), zone);
}
}
static void AddClassNegated(const int *elmv,
int elmc,
ZoneList<CharacterRange>* ranges,
Zone* zone) {
elmc--;
DCHECK_EQ(kRangeEndMarker, elmv[elmc]);
DCHECK_NE(0x0000, elmv[0]);
DCHECK_NE(String::kMaxCodePoint, elmv[elmc - 1]);
uc16 last = 0x0000;
for (int i = 0; i < elmc; i += 2) {
DCHECK(last <= elmv[i] - 1);
DCHECK(elmv[i] < elmv[i + 1]);
ranges->Add(CharacterRange::Range(last, elmv[i] - 1), zone);
last = elmv[i + 1];
}
ranges->Add(CharacterRange::Range(last, String::kMaxCodePoint), zone);
}
void CharacterRange::AddClassEscape(char type, ZoneList<CharacterRange>* ranges,
bool add_unicode_case_equivalents,
Zone* zone) {
if (add_unicode_case_equivalents && (type == 'w' || type == 'W')) {
// See #sec-runtime-semantics-wordcharacters-abstract-operation
// In case of unicode and ignore_case, we need to create the closure over
// case equivalent characters before negating.
ZoneList<CharacterRange>* new_ranges =
new (zone) ZoneList<CharacterRange>(2, zone);
AddClass(kWordRanges, kWordRangeCount, new_ranges, zone);
AddUnicodeCaseEquivalents(new_ranges, zone);
if (type == 'W') {
ZoneList<CharacterRange>* negated =
new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::Negate(new_ranges, negated, zone);
new_ranges = negated;
}
ranges->AddAll(*new_ranges, zone);
return;
}
AddClassEscape(type, ranges, zone);
}
void CharacterRange::AddClassEscape(char type, ZoneList<CharacterRange>* ranges,
Zone* zone) {
switch (type) {
case 's':
AddClass(kSpaceRanges, kSpaceRangeCount, ranges, zone);
break;
case 'S':
AddClassNegated(kSpaceRanges, kSpaceRangeCount, ranges, zone);
break;
case 'w':
AddClass(kWordRanges, kWordRangeCount, ranges, zone);
break;
case 'W':
AddClassNegated(kWordRanges, kWordRangeCount, ranges, zone);
break;
case 'd':
AddClass(kDigitRanges, kDigitRangeCount, ranges, zone);
break;
case 'D':
AddClassNegated(kDigitRanges, kDigitRangeCount, ranges, zone);
break;
case '.':
AddClassNegated(kLineTerminatorRanges,
kLineTerminatorRangeCount,
ranges,
zone);
break;
// This is not a character range as defined by the spec but a
// convenient shorthand for a character class that matches any
// character.
case '*':
ranges->Add(CharacterRange::Everything(), zone);
break;
// This is the set of characters matched by the $ and ^ symbols
// in multiline mode.
case 'n':
AddClass(kLineTerminatorRanges,
kLineTerminatorRangeCount,
ranges,
zone);
break;
default:
UNREACHABLE();
}
}
Vector<const int> CharacterRange::GetWordBounds() {
return Vector<const int>(kWordRanges, kWordRangeCount - 1);
}
// static
void CharacterRange::AddCaseEquivalents(Isolate* isolate, Zone* zone,
ZoneList<CharacterRange>* ranges,
bool is_one_byte) {
CharacterRange::Canonicalize(ranges);
int range_count = ranges->length();
#ifdef V8_INTL_SUPPORT
icu::UnicodeSet already_added;
icu::UnicodeSet others;
for (int i = 0; i < range_count; i++) {
CharacterRange range = ranges->at(i);
uc32 bottom = range.from();
if (bottom > String::kMaxUtf16CodeUnit) continue;
uc32 top = Min(range.to(), String::kMaxUtf16CodeUnit);
// Nothing to be done for surrogates.
if (bottom >= kLeadSurrogateStart && top <= kTrailSurrogateEnd) continue;
if (is_one_byte && !RangeContainsLatin1Equivalents(range)) {
if (bottom > String::kMaxOneByteCharCode) continue;
if (top > String::kMaxOneByteCharCode) top = String::kMaxOneByteCharCode;
}
already_added.add(bottom, top);
icu::Locale locale = icu::Locale::getRoot();
while (bottom <= top) {
icu::UnicodeString upper(bottom);
upper.toUpper(locale);
icu::UnicodeSet expanded(bottom, bottom);
expanded.closeOver(USET_CASE_INSENSITIVE);
for (int32_t i = 0; i < expanded.getRangeCount(); i++) {
UChar32 start = expanded.getRangeStart(i);
UChar32 end = expanded.getRangeEnd(i);
while (start <= end) {
icu::UnicodeString upper2(start);
upper2.toUpper(locale);
// Only add if the upper case are the same.
if (upper[0] == upper2[0]) {
// #sec-runtime-semantics-canonicalize-ch
// 3.g. If the numeric value of ch ≥ 128 and the numeric value of
// cu < 128, return ch.
if (bottom >= 128 && start < 128) {
others.add(bottom);
} else {
// 3.h. 3.h. 3.h. Return cu.
others.add(start);
}
}
start++;
}
}
bottom++;
}
}
others.removeAll(already_added);
for (int32_t i = 0; i < others.getRangeCount(); i++) {
UChar32 start = others.getRangeStart(i);
UChar32 end = others.getRangeEnd(i);
if (start == end) {
ranges->Add(CharacterRange::Singleton(start), zone);
} else {
ranges->Add(CharacterRange::Range(start, end), zone);
}
}
#else
for (int i = 0; i < range_count; i++) {
CharacterRange range = ranges->at(i);
uc32 bottom = range.from();
if (bottom > String::kMaxUtf16CodeUnit) continue;
uc32 top = Min(range.to(), String::kMaxUtf16CodeUnit);
// Nothing to be done for surrogates.
if (bottom >= kLeadSurrogateStart && top <= kTrailSurrogateEnd) continue;
if (is_one_byte && !RangeContainsLatin1Equivalents(range)) {
if (bottom > String::kMaxOneByteCharCode) continue;
if (top > String::kMaxOneByteCharCode) top = String::kMaxOneByteCharCode;
}
unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
if (top == bottom) {
// If this is a singleton we just expand the one character.
int length = isolate->jsregexp_uncanonicalize()->get(bottom, '\0', chars);
for (int i = 0; i < length; i++) {
uc32 chr = chars[i];
if (chr != bottom) {
ranges->Add(CharacterRange::Singleton(chars[i]), zone);
}
}
} else {
// If this is a range we expand the characters block by block, expanding
// contiguous subranges (blocks) one at a time. The approach is as
// follows. For a given start character we look up the remainder of the
// block that contains it (represented by the end point), for instance we
// find 'z' if the character is 'c'. A block is characterized by the
// property that all characters uncanonicalize in the same way, except
// that each entry in the result is incremented by the distance from the
// first element. So a-z is a block because 'a' uncanonicalizes to ['a',
// 'A'] and the k'th letter uncanonicalizes to ['a' + k, 'A' + k]. Once
// we've found the end point we look up its uncanonicalization and
// produce a range for each element. For instance for [c-f] we look up
// ['z', 'Z'] and produce [c-f] and [C-F]. We then only add a range if
// it is not already contained in the input, so [c-f] will be skipped but
// [C-F] will be added. If this range is not completely contained in a
// block we do this for all the blocks covered by the range (handling
// characters that is not in a block as a "singleton block").
unibrow::uchar equivalents[unibrow::Ecma262UnCanonicalize::kMaxWidth];
int pos = bottom;
while (pos <= top) {
int length =
isolate->jsregexp_canonrange()->get(pos, '\0', equivalents);
uc32 block_end;
if (length == 0) {
block_end = pos;
} else {
DCHECK_EQ(1, length);
block_end = equivalents[0];
}
int end = (block_end > top) ? top : block_end;
length = isolate->jsregexp_uncanonicalize()->get(block_end, '\0',
equivalents);
for (int i = 0; i < length; i++) {
uc32 c = equivalents[i];
uc32 range_from = c - (block_end - pos);
uc32 range_to = c - (block_end - end);
if (!(bottom <= range_from && range_to <= top)) {
ranges->Add(CharacterRange::Range(range_from, range_to), zone);
}
}
pos = end + 1;
}
}
}
#endif // V8_INTL_SUPPORT
}
bool CharacterRange::IsCanonical(ZoneList<CharacterRange>* ranges) {
DCHECK_NOT_NULL(ranges);
int n = ranges->length();
if (n <= 1) return true;
int max = ranges->at(0).to();
for (int i = 1; i < n; i++) {
CharacterRange next_range = ranges->at(i);
if (next_range.from() <= max + 1) return false;
max = next_range.to();
}
return true;
}
ZoneList<CharacterRange>* CharacterSet::ranges(Zone* zone) {
if (ranges_ == nullptr) {
ranges_ = new(zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::AddClassEscape(standard_set_type_, ranges_, false, zone);
}
return ranges_;
}
// Move a number of elements in a zonelist to another position
// in the same list. Handles overlapping source and target areas.
static void MoveRanges(ZoneList<CharacterRange>* list,
int from,
int to,
int count) {
// Ranges are potentially overlapping.
if (from < to) {
for (int i = count - 1; i >= 0; i--) {
list->at(to + i) = list->at(from + i);
}
} else {
for (int i = 0; i < count; i++) {
list->at(to + i) = list->at(from + i);
}
}
}
static int InsertRangeInCanonicalList(ZoneList<CharacterRange>* list,
int count,
CharacterRange insert) {
// Inserts a range into list[0..count[, which must be sorted
// by from value and non-overlapping and non-adjacent, using at most
// list[0..count] for the result. Returns the number of resulting
// canonicalized ranges. Inserting a range may collapse existing ranges into
// fewer ranges, so the return value can be anything in the range 1..count+1.
uc32 from = insert.from();
uc32 to = insert.to();
int start_pos = 0;
int end_pos = count;
for (int i = count - 1; i >= 0; i--) {
CharacterRange current = list->at(i);
if (current.from() > to + 1) {
end_pos = i;
} else if (current.to() + 1 < from) {
start_pos = i + 1;
break;
}
}
// Inserted range overlaps, or is adjacent to, ranges at positions
// [start_pos..end_pos[. Ranges before start_pos or at or after end_pos are
// not affected by the insertion.
// If start_pos == end_pos, the range must be inserted before start_pos.
// if start_pos < end_pos, the entire range from start_pos to end_pos
// must be merged with the insert range.
if (start_pos == end_pos) {
// Insert between existing ranges at position start_pos.
if (start_pos < count) {
MoveRanges(list, start_pos, start_pos + 1, count - start_pos);
}
list->at(start_pos) = insert;
return count + 1;
}
if (start_pos + 1 == end_pos) {
// Replace single existing range at position start_pos.
CharacterRange to_replace = list->at(start_pos);
int new_from = Min(to_replace.from(), from);
int new_to = Max(to_replace.to(), to);
list->at(start_pos) = CharacterRange::Range(new_from, new_to);
return count;
}
// Replace a number of existing ranges from start_pos to end_pos - 1.
// Move the remaining ranges down.
int new_from = Min(list->at(start_pos).from(), from);
int new_to = Max(list->at(end_pos - 1).to(), to);
if (end_pos < count) {
MoveRanges(list, end_pos, start_pos + 1, count - end_pos);
}
list->at(start_pos) = CharacterRange::Range(new_from, new_to);
return count - (end_pos - start_pos) + 1;
}
void CharacterSet::Canonicalize() {
// Special/default classes are always considered canonical. The result
// of calling ranges() will be sorted.
if (ranges_ == nullptr) return;
CharacterRange::Canonicalize(ranges_);
}
void CharacterRange::Canonicalize(ZoneList<CharacterRange>* character_ranges) {
if (character_ranges->length() <= 1) return;
// Check whether ranges are already canonical (increasing, non-overlapping,
// non-adjacent).
int n = character_ranges->length();
int max = character_ranges->at(0).to();
int i = 1;
while (i < n) {
CharacterRange current = character_ranges->at(i);
if (current.from() <= max + 1) {
break;
}
max = current.to();
i++;
}
// Canonical until the i'th range. If that's all of them, we are done.
if (i == n) return;
// The ranges at index i and forward are not canonicalized. Make them so by
// doing the equivalent of insertion sort (inserting each into the previous
// list, in order).
// Notice that inserting a range can reduce the number of ranges in the
// result due to combining of adjacent and overlapping ranges.
int read = i; // Range to insert.
int num_canonical = i; // Length of canonicalized part of list.
do {
num_canonical = InsertRangeInCanonicalList(character_ranges,
num_canonical,
character_ranges->at(read));
read++;
} while (read < n);
character_ranges->Rewind(num_canonical);
DCHECK(CharacterRange::IsCanonical(character_ranges));
}
void CharacterRange::Negate(ZoneList<CharacterRange>* ranges,
ZoneList<CharacterRange>* negated_ranges,
Zone* zone) {
DCHECK(CharacterRange::IsCanonical(ranges));
DCHECK_EQ(0, negated_ranges->length());
int range_count = ranges->length();
uc32 from = 0;
int i = 0;
if (range_count > 0 && ranges->at(0).from() == 0) {
from = ranges->at(0).to() + 1;
i = 1;
}
while (i < range_count) {
CharacterRange range = ranges->at(i);
negated_ranges->Add(CharacterRange::Range(from, range.from() - 1), zone);
from = range.to() + 1;
i++;
}
if (from < String::kMaxCodePoint) {
negated_ranges->Add(CharacterRange::Range(from, String::kMaxCodePoint),
zone);
}
}
// ------------------------------------------------------------------- // -------------------------------------------------------------------
// Splay tree // Splay tree
...@@ -6953,5 +5258,12 @@ void RegExpResultsCache::Clear(FixedArray cache) { ...@@ -6953,5 +5258,12 @@ void RegExpResultsCache::Clear(FixedArray cache) {
} }
} }
// We need to check for the following characters: 0x39C 0x3BC 0x178.
bool RangeContainsLatin1Equivalents(CharacterRange range) {
// TODO(dcarney): this could be a lot more efficient.
return range.Contains(0x039C) || range.Contains(0x03BC) ||
range.Contains(0x0178);
}
} // namespace internal } // namespace internal
} // namespace v8 } // namespace v8
src/regexp/jsregexp.h
View file @ d61a558a
...@@ -290,35 +290,6 @@ class DispatchTable : public ZoneObject { ...@@ -290,35 +290,6 @@ class DispatchTable : public ZoneObject {
ZoneSplayTree<Config> tree_; ZoneSplayTree<Config> tree_;
}; };
// Categorizes character ranges into BMP, non-BMP, lead, and trail surrogates.
class UnicodeRangeSplitter {
public:
V8_EXPORT_PRIVATE UnicodeRangeSplitter(Zone* zone,
ZoneList<CharacterRange>* base);
void Call(uc32 from, DispatchTable::Entry entry);
ZoneList<CharacterRange>* bmp() { return bmp_; }
ZoneList<CharacterRange>* lead_surrogates() { return lead_surrogates_; }
ZoneList<CharacterRange>* trail_surrogates() { return trail_surrogates_; }
ZoneList<CharacterRange>* non_bmp() const { return non_bmp_; }
private:
static const int kBase = 0;
// Separate ranges into
static const int kBmpCodePoints = 1;
static const int kLeadSurrogates = 2;
static const int kTrailSurrogates = 3;
static const int kNonBmpCodePoints = 4;
Zone* zone_;
DispatchTable table_;
ZoneList<CharacterRange>* bmp_;
ZoneList<CharacterRange>* lead_surrogates_;
ZoneList<CharacterRange>* trail_surrogates_;
ZoneList<CharacterRange>* non_bmp_;
};
#define FOR_EACH_NODE_TYPE(VISIT) \ #define FOR_EACH_NODE_TYPE(VISIT) \
VISIT(End) \ VISIT(End) \
VISIT(Action) \ VISIT(Action) \
......
src/regexp/regexp-compiler-tonode.cc 0 → 100644
View file @ d61a558a
// Copyright 2019 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.
#include "src/regexp/regexp-compiler.h"
#include "src/regexp/jsregexp.h"
#include "src/strings/unicode-inl.h"
#include "src/utils/splay-tree-inl.h"
#include "src/zone/zone-list-inl.h"
#ifdef V8_INTL_SUPPORT
#include "unicode/locid.h"
#include "unicode/uniset.h"
#include "unicode/utypes.h"
#endif // V8_INTL_SUPPORT
namespace v8 {
namespace internal {
using namespace regexp_compiler_constants; // NOLINT(build/namespaces)
// Explicit template instantiations.
template class ZoneSplayTree<DispatchTable::Config>;
template void DispatchTable::ForEach<UnicodeRangeSplitter>(
UnicodeRangeSplitter*);
// -------------------------------------------------------------------
// Tree to graph conversion
RegExpNode* RegExpAtom::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
ZoneList<TextElement>* elms =
new (compiler->zone()) ZoneList<TextElement>(1, compiler->zone());
elms->Add(TextElement::Atom(this), compiler->zone());
return new (compiler->zone())
TextNode(elms, compiler->read_backward(), on_success);
}
RegExpNode* RegExpText::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return new (compiler->zone())
TextNode(elements(), compiler->read_backward(), on_success);
}
static bool CompareInverseRanges(ZoneList<CharacterRange>* ranges,
const int* special_class, int length) {
length--; // Remove final marker.
DCHECK_EQ(kRangeEndMarker, special_class[length]);
DCHECK_NE(0, ranges->length());
DCHECK_NE(0, length);
DCHECK_NE(0, special_class[0]);
if (ranges->length() != (length >> 1) + 1) {
return false;
}
CharacterRange range = ranges->at(0);
if (range.from() != 0) {
return false;
}
for (int i = 0; i < length; i += 2) {
if (special_class[i] != (range.to() + 1)) {
return false;
}
range = ranges->at((i >> 1) + 1);
if (special_class[i + 1] != range.from()) {
return false;
}
}
if (range.to() != String::kMaxCodePoint) {
return false;
}
return true;
}
static bool CompareRanges(ZoneList<CharacterRange>* ranges,
const int* special_class, int length) {
length--; // Remove final marker.
DCHECK_EQ(kRangeEndMarker, special_class[length]);
if (ranges->length() * 2 != length) {
return false;
}
for (int i = 0; i < length; i += 2) {
CharacterRange range = ranges->at(i >> 1);
if (range.from() != special_class[i] ||
range.to() != special_class[i + 1] - 1) {
return false;
}
}
return true;
}
bool RegExpCharacterClass::is_standard(Zone* zone) {
// TODO(lrn): Remove need for this function, by not throwing away information
// along the way.
if (is_negated()) {
return false;
}
if (set_.is_standard()) {
return true;
}
if (CompareRanges(set_.ranges(zone), kSpaceRanges, kSpaceRangeCount)) {
set_.set_standard_set_type('s');
return true;
}
if (CompareInverseRanges(set_.ranges(zone), kSpaceRanges, kSpaceRangeCount)) {
set_.set_standard_set_type('S');
return true;
}
if (CompareInverseRanges(set_.ranges(zone), kLineTerminatorRanges,
kLineTerminatorRangeCount)) {
set_.set_standard_set_type('.');
return true;
}
if (CompareRanges(set_.ranges(zone), kLineTerminatorRanges,
kLineTerminatorRangeCount)) {
set_.set_standard_set_type('n');
return true;
}
if (CompareRanges(set_.ranges(zone), kWordRanges, kWordRangeCount)) {
set_.set_standard_set_type('w');
return true;
}
if (CompareInverseRanges(set_.ranges(zone), kWordRanges, kWordRangeCount)) {
set_.set_standard_set_type('W');
return true;
}
return false;
}
UnicodeRangeSplitter::UnicodeRangeSplitter(Zone* zone,
ZoneList<CharacterRange>* base)
: zone_(zone),
table_(zone),
bmp_(nullptr),
lead_surrogates_(nullptr),
trail_surrogates_(nullptr),
non_bmp_(nullptr) {
// The unicode range splitter categorizes given character ranges into:
// - Code points from the BMP representable by one code unit.
// - Code points outside the BMP that need to be split into surrogate pairs.
// - Lone lead surrogates.
// - Lone trail surrogates.
// Lone surrogates are valid code points, even though no actual characters.
// They require special matching to make sure we do not split surrogate pairs.
// We use the dispatch table to accomplish this. The base range is split up
// by the table by the overlay ranges, and the Call callback is used to
// filter and collect ranges for each category.
for (int i = 0; i < base->length(); i++) {
table_.AddRange(base->at(i), kBase, zone_);
}
// Add overlay ranges.
table_.AddRange(CharacterRange::Range(0, kLeadSurrogateStart - 1),
kBmpCodePoints, zone_);
table_.AddRange(CharacterRange::Range(kLeadSurrogateStart, kLeadSurrogateEnd),
kLeadSurrogates, zone_);
table_.AddRange(
CharacterRange::Range(kTrailSurrogateStart, kTrailSurrogateEnd),
kTrailSurrogates, zone_);
table_.AddRange(
CharacterRange::Range(kTrailSurrogateEnd + 1, kNonBmpStart - 1),
kBmpCodePoints, zone_);
table_.AddRange(CharacterRange::Range(kNonBmpStart, kNonBmpEnd),
kNonBmpCodePoints, zone_);
table_.ForEach(this);
}
void UnicodeRangeSplitter::Call(uc32 from, DispatchTable::Entry entry) {
OutSet* outset = entry.out_set();
if (!outset->Get(kBase)) return;
ZoneList<CharacterRange>** target = nullptr;
if (outset->Get(kBmpCodePoints)) {
target = &bmp_;
} else if (outset->Get(kLeadSurrogates)) {
target = &lead_surrogates_;
} else if (outset->Get(kTrailSurrogates)) {
target = &trail_surrogates_;
} else {
DCHECK(outset->Get(kNonBmpCodePoints));
target = &non_bmp_;
}
if (*target == nullptr)
*target = new (zone_) ZoneList<CharacterRange>(2, zone_);
(*target)->Add(CharacterRange::Range(entry.from(), entry.to()), zone_);
}
void AddBmpCharacters(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success, UnicodeRangeSplitter* splitter) {
ZoneList<CharacterRange>* bmp = splitter->bmp();
if (bmp == nullptr) return;
JSRegExp::Flags default_flags = JSRegExp::Flags();
result->AddAlternative(GuardedAlternative(TextNode::CreateForCharacterRanges(
compiler->zone(), bmp, compiler->read_backward(), on_success,
default_flags)));
}
void AddNonBmpSurrogatePairs(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success,
UnicodeRangeSplitter* splitter) {
ZoneList<CharacterRange>* non_bmp = splitter->non_bmp();
if (non_bmp == nullptr) return;
DCHECK(!compiler->one_byte());
Zone* zone = compiler->zone();
JSRegExp::Flags default_flags = JSRegExp::Flags();
CharacterRange::Canonicalize(non_bmp);
for (int i = 0; i < non_bmp->length(); i++) {
// Match surrogate pair.
// E.g. [\u10005-\u11005] becomes
// \ud800[\udc05-\udfff]|
// [\ud801-\ud803][\udc00-\udfff]|
// \ud804[\udc00-\udc05]
uc32 from = non_bmp->at(i).from();
uc32 to = non_bmp->at(i).to();
uc16 from_l = unibrow::Utf16::LeadSurrogate(from);
uc16 from_t = unibrow::Utf16::TrailSurrogate(from);
uc16 to_l = unibrow::Utf16::LeadSurrogate(to);
uc16 to_t = unibrow::Utf16::TrailSurrogate(to);
if (from_l == to_l) {
// The lead surrogate is the same.
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Singleton(from_l),
CharacterRange::Range(from_t, to_t), compiler->read_backward(),
on_success, default_flags)));
} else {
if (from_t != kTrailSurrogateStart) {
// Add [from_l][from_t-\udfff]
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Singleton(from_l),
CharacterRange::Range(from_t, kTrailSurrogateEnd),
compiler->read_backward(), on_success, default_flags)));
from_l++;
}
if (to_t != kTrailSurrogateEnd) {
// Add [to_l][\udc00-to_t]
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Singleton(to_l),
CharacterRange::Range(kTrailSurrogateStart, to_t),
compiler->read_backward(), on_success, default_flags)));
to_l--;
}
if (from_l <= to_l) {
// Add [from_l-to_l][\udc00-\udfff]
result->AddAlternative(
GuardedAlternative(TextNode::CreateForSurrogatePair(
zone, CharacterRange::Range(from_l, to_l),
CharacterRange::Range(kTrailSurrogateStart, kTrailSurrogateEnd),
compiler->read_backward(), on_success, default_flags)));
}
}
}
}
RegExpNode* NegativeLookaroundAgainstReadDirectionAndMatch(
RegExpCompiler* compiler, ZoneList<CharacterRange>* lookbehind,
ZoneList<CharacterRange>* match, RegExpNode* on_success, bool read_backward,
JSRegExp::Flags flags) {
Zone* zone = compiler->zone();
RegExpNode* match_node = TextNode::CreateForCharacterRanges(
zone, match, read_backward, on_success, flags);
int stack_register = compiler->UnicodeLookaroundStackRegister();
int position_register = compiler->UnicodeLookaroundPositionRegister();
RegExpLookaround::Builder lookaround(false, match_node, stack_register,
position_register);
RegExpNode* negative_match = TextNode::CreateForCharacterRanges(
zone, lookbehind, !read_backward, lookaround.on_match_success(), flags);
return lookaround.ForMatch(negative_match);
}
RegExpNode* MatchAndNegativeLookaroundInReadDirection(
RegExpCompiler* compiler, ZoneList<CharacterRange>* match,
ZoneList<CharacterRange>* lookahead, RegExpNode* on_success,
bool read_backward, JSRegExp::Flags flags) {
Zone* zone = compiler->zone();
int stack_register = compiler->UnicodeLookaroundStackRegister();
int position_register = compiler->UnicodeLookaroundPositionRegister();
RegExpLookaround::Builder lookaround(false, on_success, stack_register,
position_register);
RegExpNode* negative_match = TextNode::CreateForCharacterRanges(
zone, lookahead, read_backward, lookaround.on_match_success(), flags);
return TextNode::CreateForCharacterRanges(
zone, match, read_backward, lookaround.ForMatch(negative_match), flags);
}
void AddLoneLeadSurrogates(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success,
UnicodeRangeSplitter* splitter) {
JSRegExp::Flags default_flags = JSRegExp::Flags();
ZoneList<CharacterRange>* lead_surrogates = splitter->lead_surrogates();
if (lead_surrogates == nullptr) return;
Zone* zone = compiler->zone();
// E.g. \ud801 becomes \ud801(?![\udc00-\udfff]).
ZoneList<CharacterRange>* trail_surrogates = CharacterRange::List(
zone, CharacterRange::Range(kTrailSurrogateStart, kTrailSurrogateEnd));
RegExpNode* match;
if (compiler->read_backward()) {
// Reading backward. Assert that reading forward, there is no trail
// surrogate, and then backward match the lead surrogate.
match = NegativeLookaroundAgainstReadDirectionAndMatch(
compiler, trail_surrogates, lead_surrogates, on_success, true,
default_flags);
} else {
// Reading forward. Forward match the lead surrogate and assert that
// no trail surrogate follows.
match = MatchAndNegativeLookaroundInReadDirection(
compiler, lead_surrogates, trail_surrogates, on_success, false,
default_flags);
}
result->AddAlternative(GuardedAlternative(match));
}
void AddLoneTrailSurrogates(RegExpCompiler* compiler, ChoiceNode* result,
RegExpNode* on_success,
UnicodeRangeSplitter* splitter) {
JSRegExp::Flags default_flags = JSRegExp::Flags();
ZoneList<CharacterRange>* trail_surrogates = splitter->trail_surrogates();
if (trail_surrogates == nullptr) return;
Zone* zone = compiler->zone();
// E.g. \udc01 becomes (?<![\ud800-\udbff])\udc01
ZoneList<CharacterRange>* lead_surrogates = CharacterRange::List(
zone, CharacterRange::Range(kLeadSurrogateStart, kLeadSurrogateEnd));
RegExpNode* match;
if (compiler->read_backward()) {
// Reading backward. Backward match the trail surrogate and assert that no
// lead surrogate precedes it.
match = MatchAndNegativeLookaroundInReadDirection(
compiler, trail_surrogates, lead_surrogates, on_success, true,
default_flags);
} else {
// Reading forward. Assert that reading backward, there is no lead
// surrogate, and then forward match the trail surrogate.
match = NegativeLookaroundAgainstReadDirectionAndMatch(
compiler, lead_surrogates, trail_surrogates, on_success, false,
default_flags);
}
result->AddAlternative(GuardedAlternative(match));
}
RegExpNode* UnanchoredAdvance(RegExpCompiler* compiler,
RegExpNode* on_success) {
// This implements ES2015 21.2.5.2.3, AdvanceStringIndex.
DCHECK(!compiler->read_backward());
Zone* zone = compiler->zone();
// Advance any character. If the character happens to be a lead surrogate and
// we advanced into the middle of a surrogate pair, it will work out, as
// nothing will match from there. We will have to advance again, consuming
// the associated trail surrogate.
ZoneList<CharacterRange>* range = CharacterRange::List(
zone, CharacterRange::Range(0, String::kMaxUtf16CodeUnit));
JSRegExp::Flags default_flags = JSRegExp::Flags();
return TextNode::CreateForCharacterRanges(zone, range, false, on_success,
default_flags);
}
void AddUnicodeCaseEquivalents(ZoneList<CharacterRange>* ranges, Zone* zone) {
#ifdef V8_INTL_SUPPORT
DCHECK(CharacterRange::IsCanonical(ranges));
// Micro-optimization to avoid passing large ranges to UnicodeSet::closeOver.
// See also https://crbug.com/v8/6727.
// TODO(jgruber): This only covers the special case of the {0,0x10FFFF} range,
// which we use frequently internally. But large ranges can also easily be
// created by the user. We might want to have a more general caching mechanism
// for such ranges.
if (ranges->length() == 1 && ranges->at(0).IsEverything(kNonBmpEnd)) return;
// Use ICU to compute the case fold closure over the ranges.
icu::UnicodeSet set;
for (int i = 0; i < ranges->length(); i++) {
set.add(ranges->at(i).from(), ranges->at(i).to());
}
ranges->Clear();
set.closeOver(USET_CASE_INSENSITIVE);
// Full case mapping map single characters to multiple characters.
// Those are represented as strings in the set. Remove them so that
// we end up with only simple and common case mappings.
set.removeAllStrings();
for (int i = 0; i < set.getRangeCount(); i++) {
ranges->Add(CharacterRange::Range(set.getRangeStart(i), set.getRangeEnd(i)),
zone);
}
// No errors and everything we collected have been ranges.
CharacterRange::Canonicalize(ranges);
#endif // V8_INTL_SUPPORT
}
RegExpNode* RegExpCharacterClass::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
set_.Canonicalize();
Zone* zone = compiler->zone();
ZoneList<CharacterRange>* ranges = this->ranges(zone);
if (NeedsUnicodeCaseEquivalents(flags_)) {
AddUnicodeCaseEquivalents(ranges, zone);
}
if (IsUnicode(flags_) && !compiler->one_byte() &&
!contains_split_surrogate()) {
if (is_negated()) {
ZoneList<CharacterRange>* negated =
new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::Negate(ranges, negated, zone);
ranges = negated;
}
if (ranges->length() == 0) {
JSRegExp::Flags default_flags;
RegExpCharacterClass* fail =
new (zone) RegExpCharacterClass(zone, ranges, default_flags);
return new (zone) TextNode(fail, compiler->read_backward(), on_success);
}
if (standard_type() == '*') {
return UnanchoredAdvance(compiler, on_success);
} else {
ChoiceNode* result = new (zone) ChoiceNode(2, zone);
UnicodeRangeSplitter splitter(zone, ranges);
AddBmpCharacters(compiler, result, on_success, &splitter);
AddNonBmpSurrogatePairs(compiler, result, on_success, &splitter);
AddLoneLeadSurrogates(compiler, result, on_success, &splitter);
AddLoneTrailSurrogates(compiler, result, on_success, &splitter);
return result;
}
} else {
return new (zone) TextNode(this, compiler->read_backward(), on_success);
}
}
int CompareFirstChar(RegExpTree* const* a, RegExpTree* const* b) {
RegExpAtom* atom1 = (*a)->AsAtom();
RegExpAtom* atom2 = (*b)->AsAtom();
uc16 character1 = atom1->data().at(0);
uc16 character2 = atom2->data().at(0);
if (character1 < character2) return -1;
if (character1 > character2) return 1;
return 0;
}
#ifdef V8_INTL_SUPPORT
// Case Insensitve comparesion
int CompareFirstCharCaseInsensitve(RegExpTree* const* a, RegExpTree* const* b) {
RegExpAtom* atom1 = (*a)->AsAtom();
RegExpAtom* atom2 = (*b)->AsAtom();
icu::UnicodeString character1(atom1->data().at(0));
return character1.caseCompare(atom2->data().at(0), U_FOLD_CASE_DEFAULT);
}
#else
static unibrow::uchar Canonical(
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize,
unibrow::uchar c) {
unibrow::uchar chars[unibrow::Ecma262Canonicalize::kMaxWidth];
int length = canonicalize->get(c, '\0', chars);
DCHECK_LE(length, 1);
unibrow::uchar canonical = c;
if (length == 1) canonical = chars[0];
return canonical;
}
int CompareFirstCharCaseIndependent(
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize,
RegExpTree* const* a, RegExpTree* const* b) {
RegExpAtom* atom1 = (*a)->AsAtom();
RegExpAtom* atom2 = (*b)->AsAtom();
unibrow::uchar character1 = atom1->data().at(0);
unibrow::uchar character2 = atom2->data().at(0);
if (character1 == character2) return 0;
if (character1 >= 'a' || character2 >= 'a') {
character1 = Canonical(canonicalize, character1);
character2 = Canonical(canonicalize, character2);
}
return static_cast<int>(character1) - static_cast<int>(character2);
}
#endif // V8_INTL_SUPPORT
// We can stable sort runs of atoms, since the order does not matter if they
// start with different characters.
// Returns true if any consecutive atoms were found.
bool RegExpDisjunction::SortConsecutiveAtoms(RegExpCompiler* compiler) {
ZoneList<RegExpTree*>* alternatives = this->alternatives();
int length = alternatives->length();
bool found_consecutive_atoms = false;
for (int i = 0; i < length; i++) {
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (alternative->IsAtom()) break;
i++;
}
// i is length or it is the index of an atom.
if (i == length) break;
int first_atom = i;
JSRegExp::Flags flags = alternatives->at(i)->AsAtom()->flags();
i++;
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (!alternative->IsAtom()) break;
if (alternative->AsAtom()->flags() != flags) break;
i++;
}
// Sort atoms to get ones with common prefixes together.
// This step is more tricky if we are in a case-independent regexp,
// because it would change /is|I/ to /I|is/, and order matters when
// the regexp parts don't match only disjoint starting points. To fix
// this we have a version of CompareFirstChar that uses case-
// independent character classes for comparison.
DCHECK_LT(first_atom, alternatives->length());
DCHECK_LE(i, alternatives->length());
DCHECK_LE(first_atom, i);
if (IgnoreCase(flags)) {
#ifdef V8_INTL_SUPPORT
alternatives->StableSort(CompareFirstCharCaseInsensitve, first_atom,
i - first_atom);
#else
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize =
compiler->isolate()->regexp_macro_assembler_canonicalize();
auto compare_closure = [canonicalize](RegExpTree* const* a,
RegExpTree* const* b) {
return CompareFirstCharCaseIndependent(canonicalize, a, b);
};
alternatives->StableSort(compare_closure, first_atom, i - first_atom);
#endif // V8_INTL_SUPPORT
} else {
alternatives->StableSort(CompareFirstChar, first_atom, i - first_atom);
}
if (i - first_atom > 1) found_consecutive_atoms = true;
}
return found_consecutive_atoms;
}
// Optimizes ab|ac|az to a(?:b|c|d).
void RegExpDisjunction::RationalizeConsecutiveAtoms(RegExpCompiler* compiler) {
Zone* zone = compiler->zone();
ZoneList<RegExpTree*>* alternatives = this->alternatives();
int length = alternatives->length();
int write_posn = 0;
int i = 0;
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (!alternative->IsAtom()) {
alternatives->at(write_posn++) = alternatives->at(i);
i++;
continue;
}
RegExpAtom* const atom = alternative->AsAtom();
JSRegExp::Flags flags = atom->flags();
#ifdef V8_INTL_SUPPORT
icu::UnicodeString common_prefix(atom->data().at(0));
#else
unibrow::uchar common_prefix = atom->data().at(0);
#endif // V8_INTL_SUPPORT
int first_with_prefix = i;
int prefix_length = atom->length();
i++;
while (i < length) {
alternative = alternatives->at(i);
if (!alternative->IsAtom()) break;
RegExpAtom* const atom = alternative->AsAtom();
if (atom->flags() != flags) break;
#ifdef V8_INTL_SUPPORT
icu::UnicodeString new_prefix(atom->data().at(0));
if (new_prefix != common_prefix) {
if (!IgnoreCase(flags)) break;
if (common_prefix.caseCompare(new_prefix, U_FOLD_CASE_DEFAULT) != 0)
break;
}
#else
unibrow::uchar new_prefix = atom->data().at(0);
if (new_prefix != common_prefix) {
if (!IgnoreCase(flags)) break;
unibrow::Mapping<unibrow::Ecma262Canonicalize>* canonicalize =
compiler->isolate()->regexp_macro_assembler_canonicalize();
new_prefix = Canonical(canonicalize, new_prefix);
common_prefix = Canonical(canonicalize, common_prefix);
if (new_prefix != common_prefix) break;
}
#endif // V8_INTL_SUPPORT
prefix_length = Min(prefix_length, atom->length());
i++;
}
if (i > first_with_prefix + 2) {
// Found worthwhile run of alternatives with common prefix of at least one
// character. The sorting function above did not sort on more than one
// character for reasons of correctness, but there may still be a longer
// common prefix if the terms were similar or presorted in the input.
// Find out how long the common prefix is.
int run_length = i - first_with_prefix;
RegExpAtom* const atom = alternatives->at(first_with_prefix)->AsAtom();
for (int j = 1; j < run_length && prefix_length > 1; j++) {
RegExpAtom* old_atom =
alternatives->at(j + first_with_prefix)->AsAtom();
for (int k = 1; k < prefix_length; k++) {
if (atom->data().at(k) != old_atom->data().at(k)) {
prefix_length = k;
break;
}
}
}
RegExpAtom* prefix = new (zone)
RegExpAtom(atom->data().SubVector(0, prefix_length), flags);
ZoneList<RegExpTree*>* pair = new (zone) ZoneList<RegExpTree*>(2, zone);
pair->Add(prefix, zone);
ZoneList<RegExpTree*>* suffixes =
new (zone) ZoneList<RegExpTree*>(run_length, zone);
for (int j = 0; j < run_length; j++) {
RegExpAtom* old_atom =
alternatives->at(j + first_with_prefix)->AsAtom();
int len = old_atom->length();
if (len == prefix_length) {
suffixes->Add(new (zone) RegExpEmpty(), zone);
} else {
RegExpTree* suffix = new (zone) RegExpAtom(
old_atom->data().SubVector(prefix_length, old_atom->length()),
flags);
suffixes->Add(suffix, zone);
}
}
pair->Add(new (zone) RegExpDisjunction(suffixes), zone);
alternatives->at(write_posn++) = new (zone) RegExpAlternative(pair);
} else {
// Just copy any non-worthwhile alternatives.
for (int j = first_with_prefix; j < i; j++) {
alternatives->at(write_posn++) = alternatives->at(j);
}
}
}
alternatives->Rewind(write_posn); // Trim end of array.
}
// Optimizes b|c|z to [bcz].
void RegExpDisjunction::FixSingleCharacterDisjunctions(
RegExpCompiler* compiler) {
Zone* zone = compiler->zone();
ZoneList<RegExpTree*>* alternatives = this->alternatives();
int length = alternatives->length();
int write_posn = 0;
int i = 0;
while (i < length) {
RegExpTree* alternative = alternatives->at(i);
if (!alternative->IsAtom()) {
alternatives->at(write_posn++) = alternatives->at(i);
i++;
continue;
}
RegExpAtom* const atom = alternative->AsAtom();
if (atom->length() != 1) {
alternatives->at(write_posn++) = alternatives->at(i);
i++;
continue;
}
JSRegExp::Flags flags = atom->flags();
DCHECK_IMPLIES(IsUnicode(flags),
!unibrow::Utf16::IsLeadSurrogate(atom->data().at(0)));
bool contains_trail_surrogate =
unibrow::Utf16::IsTrailSurrogate(atom->data().at(0));
int first_in_run = i;
i++;
// Find a run of single-character atom alternatives that have identical
// flags (case independence and unicode-ness).
while (i < length) {
alternative = alternatives->at(i);
if (!alternative->IsAtom()) break;
RegExpAtom* const atom = alternative->AsAtom();
if (atom->length() != 1) break;
if (atom->flags() != flags) break;
DCHECK_IMPLIES(IsUnicode(flags),
!unibrow::Utf16::IsLeadSurrogate(atom->data().at(0)));
contains_trail_surrogate |=
unibrow::Utf16::IsTrailSurrogate(atom->data().at(0));
i++;
}
if (i > first_in_run + 1) {
// Found non-trivial run of single-character alternatives.
int run_length = i - first_in_run;
ZoneList<CharacterRange>* ranges =
new (zone) ZoneList<CharacterRange>(2, zone);
for (int j = 0; j < run_length; j++) {
RegExpAtom* old_atom = alternatives->at(j + first_in_run)->AsAtom();
DCHECK_EQ(old_atom->length(), 1);
ranges->Add(CharacterRange::Singleton(old_atom->data().at(0)), zone);
}
RegExpCharacterClass::CharacterClassFlags character_class_flags;
if (IsUnicode(flags) && contains_trail_surrogate) {
character_class_flags = RegExpCharacterClass::CONTAINS_SPLIT_SURROGATE;
}
alternatives->at(write_posn++) = new (zone)
RegExpCharacterClass(zone, ranges, flags, character_class_flags);
} else {
// Just copy any trivial alternatives.
for (int j = first_in_run; j < i; j++) {
alternatives->at(write_posn++) = alternatives->at(j);
}
}
}
alternatives->Rewind(write_posn); // Trim end of array.
}
RegExpNode* RegExpDisjunction::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
ZoneList<RegExpTree*>* alternatives = this->alternatives();
if (alternatives->length() > 2) {
bool found_consecutive_atoms = SortConsecutiveAtoms(compiler);
if (found_consecutive_atoms) RationalizeConsecutiveAtoms(compiler);
FixSingleCharacterDisjunctions(compiler);
if (alternatives->length() == 1) {
return alternatives->at(0)->ToNode(compiler, on_success);
}
}
int length = alternatives->length();
ChoiceNode* result =
new (compiler->zone()) ChoiceNode(length, compiler->zone());
for (int i = 0; i < length; i++) {
GuardedAlternative alternative(
alternatives->at(i)->ToNode(compiler, on_success));
result->AddAlternative(alternative);
}
return result;
}
RegExpNode* RegExpQuantifier::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return ToNode(min(), max(), is_greedy(), body(), compiler, on_success);
}
namespace {
// Desugar \b to (?<=\w)(?=\W)|(?<=\W)(?=\w) and
// \B to (?<=\w)(?=\w)|(?<=\W)(?=\W)
RegExpNode* BoundaryAssertionAsLookaround(RegExpCompiler* compiler,
RegExpNode* on_success,
RegExpAssertion::AssertionType type,
JSRegExp::Flags flags) {
DCHECK(NeedsUnicodeCaseEquivalents(flags));
Zone* zone = compiler->zone();
ZoneList<CharacterRange>* word_range =
new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::AddClassEscape('w', word_range, true, zone);
int stack_register = compiler->UnicodeLookaroundStackRegister();
int position_register = compiler->UnicodeLookaroundPositionRegister();
ChoiceNode* result = new (zone) ChoiceNode(2, zone);
// Add two choices. The (non-)boundary could start with a word or
// a non-word-character.
for (int i = 0; i < 2; i++) {
bool lookbehind_for_word = i == 0;
bool lookahead_for_word =
(type == RegExpAssertion::BOUNDARY) ^ lookbehind_for_word;
// Look to the left.
RegExpLookaround::Builder lookbehind(lookbehind_for_word, on_success,
stack_register, position_register);
RegExpNode* backward = TextNode::CreateForCharacterRanges(
zone, word_range, true, lookbehind.on_match_success(), flags);
// Look to the right.
RegExpLookaround::Builder lookahead(lookahead_for_word,
lookbehind.ForMatch(backward),
stack_register, position_register);
RegExpNode* forward = TextNode::CreateForCharacterRanges(
zone, word_range, false, lookahead.on_match_success(), flags);
result->AddAlternative(GuardedAlternative(lookahead.ForMatch(forward)));
}
return result;
}
} // anonymous namespace
RegExpNode* RegExpAssertion::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
NodeInfo info;
Zone* zone = compiler->zone();
switch (assertion_type()) {
case START_OF_LINE:
return AssertionNode::AfterNewline(on_success);
case START_OF_INPUT:
return AssertionNode::AtStart(on_success);
case BOUNDARY:
return NeedsUnicodeCaseEquivalents(flags_)
? BoundaryAssertionAsLookaround(compiler, on_success, BOUNDARY,
flags_)
: AssertionNode::AtBoundary(on_success);
case NON_BOUNDARY:
return NeedsUnicodeCaseEquivalents(flags_)
? BoundaryAssertionAsLookaround(compiler, on_success,
NON_BOUNDARY, flags_)
: AssertionNode::AtNonBoundary(on_success);
case END_OF_INPUT:
return AssertionNode::AtEnd(on_success);
case END_OF_LINE: {
// Compile $ in multiline regexps as an alternation with a positive
// lookahead in one side and an end-of-input on the other side.
// We need two registers for the lookahead.
int stack_pointer_register = compiler->AllocateRegister();
int position_register = compiler->AllocateRegister();
// The ChoiceNode to distinguish between a newline and end-of-input.
ChoiceNode* result = new (zone) ChoiceNode(2, zone);
// Create a newline atom.
ZoneList<CharacterRange>* newline_ranges =
new (zone) ZoneList<CharacterRange>(3, zone);
CharacterRange::AddClassEscape('n', newline_ranges, false, zone);
JSRegExp::Flags default_flags = JSRegExp::Flags();
RegExpCharacterClass* newline_atom =
new (zone) RegExpCharacterClass('n', default_flags);
TextNode* newline_matcher =
new (zone) TextNode(newline_atom, false,
ActionNode::PositiveSubmatchSuccess(
stack_pointer_register, position_register,
0, // No captures inside.
-1, // Ignored if no captures.
on_success));
// Create an end-of-input matcher.
RegExpNode* end_of_line = ActionNode::BeginSubmatch(
stack_pointer_register, position_register, newline_matcher);
// Add the two alternatives to the ChoiceNode.
GuardedAlternative eol_alternative(end_of_line);
result->AddAlternative(eol_alternative);
GuardedAlternative end_alternative(AssertionNode::AtEnd(on_success));
result->AddAlternative(end_alternative);
return result;
}
default:
UNREACHABLE();
}
return on_success;
}
RegExpNode* RegExpBackReference::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return new (compiler->zone())
BackReferenceNode(RegExpCapture::StartRegister(index()),
RegExpCapture::EndRegister(index()), flags_,
compiler->read_backward(), on_success);
}
RegExpNode* RegExpEmpty::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return on_success;
}
RegExpLookaround::Builder::Builder(bool is_positive, RegExpNode* on_success,
int stack_pointer_register,
int position_register,
int capture_register_count,
int capture_register_start)
: is_positive_(is_positive),
on_success_(on_success),
stack_pointer_register_(stack_pointer_register),
position_register_(position_register) {
if (is_positive_) {
on_match_success_ = ActionNode::PositiveSubmatchSuccess(
stack_pointer_register, position_register, capture_register_count,
capture_register_start, on_success_);
} else {
Zone* zone = on_success_->zone();
on_match_success_ = new (zone) NegativeSubmatchSuccess(
stack_pointer_register, position_register, capture_register_count,
capture_register_start, zone);
}
}
RegExpNode* RegExpLookaround::Builder::ForMatch(RegExpNode* match) {
if (is_positive_) {
return ActionNode::BeginSubmatch(stack_pointer_register_,
position_register_, match);
} else {
Zone* zone = on_success_->zone();
// We use a ChoiceNode to represent the negative lookaround. The first
// alternative is the negative match. On success, the end node backtracks.
// On failure, the second alternative is tried and leads to success.
// NegativeLookaheadChoiceNode is a special ChoiceNode that ignores the
// first exit when calculating quick checks.
ChoiceNode* choice_node = new (zone) NegativeLookaroundChoiceNode(
GuardedAlternative(match), GuardedAlternative(on_success_), zone);
return ActionNode::BeginSubmatch(stack_pointer_register_,
position_register_, choice_node);
}
}
RegExpNode* RegExpLookaround::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
int stack_pointer_register = compiler->AllocateRegister();
int position_register = compiler->AllocateRegister();
const int registers_per_capture = 2;
const int register_of_first_capture = 2;
int register_count = capture_count_ * registers_per_capture;
int register_start =
register_of_first_capture + capture_from_ * registers_per_capture;
RegExpNode* result;
bool was_reading_backward = compiler->read_backward();
compiler->set_read_backward(type() == LOOKBEHIND);
Builder builder(is_positive(), on_success, stack_pointer_register,
position_register, register_count, register_start);
RegExpNode* match = body_->ToNode(compiler, builder.on_match_success());
result = builder.ForMatch(match);
compiler->set_read_backward(was_reading_backward);
return result;
}
RegExpNode* RegExpCapture::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
return ToNode(body(), index(), compiler, on_success);
}
RegExpNode* RegExpCapture::ToNode(RegExpTree* body, int index,
RegExpCompiler* compiler,
RegExpNode* on_success) {
DCHECK_NOT_NULL(body);
int start_reg = RegExpCapture::StartRegister(index);
int end_reg = RegExpCapture::EndRegister(index);
if (compiler->read_backward()) std::swap(start_reg, end_reg);
RegExpNode* store_end = ActionNode::StorePosition(end_reg, true, on_success);
RegExpNode* body_node = body->ToNode(compiler, store_end);
return ActionNode::StorePosition(start_reg, true, body_node);
}
RegExpNode* RegExpAlternative::ToNode(RegExpCompiler* compiler,
RegExpNode* on_success) {
ZoneList<RegExpTree*>* children = nodes();
RegExpNode* current = on_success;
if (compiler->read_backward()) {
for (int i = 0; i < children->length(); i++) {
current = children->at(i)->ToNode(compiler, current);
}
} else {
for (int i = children->length() - 1; i >= 0; i--) {
current = children->at(i)->ToNode(compiler, current);
}
}
return current;
}
static void AddClass(const int* elmv, int elmc,
ZoneList<CharacterRange>* ranges, Zone* zone) {
elmc--;
DCHECK_EQ(kRangeEndMarker, elmv[elmc]);
for (int i = 0; i < elmc; i += 2) {
DCHECK(elmv[i] < elmv[i + 1]);
ranges->Add(CharacterRange::Range(elmv[i], elmv[i + 1] - 1), zone);
}
}
static void AddClassNegated(const int* elmv, int elmc,
ZoneList<CharacterRange>* ranges, Zone* zone) {
elmc--;
DCHECK_EQ(kRangeEndMarker, elmv[elmc]);
DCHECK_NE(0x0000, elmv[0]);
DCHECK_NE(String::kMaxCodePoint, elmv[elmc - 1]);
uc16 last = 0x0000;
for (int i = 0; i < elmc; i += 2) {
DCHECK(last <= elmv[i] - 1);
DCHECK(elmv[i] < elmv[i + 1]);
ranges->Add(CharacterRange::Range(last, elmv[i] - 1), zone);
last = elmv[i + 1];
}
ranges->Add(CharacterRange::Range(last, String::kMaxCodePoint), zone);
}
void CharacterRange::AddClassEscape(char type, ZoneList<CharacterRange>* ranges,
bool add_unicode_case_equivalents,
Zone* zone) {
if (add_unicode_case_equivalents && (type == 'w' || type == 'W')) {
// See #sec-runtime-semantics-wordcharacters-abstract-operation
// In case of unicode and ignore_case, we need to create the closure over
// case equivalent characters before negating.
ZoneList<CharacterRange>* new_ranges =
new (zone) ZoneList<CharacterRange>(2, zone);
AddClass(kWordRanges, kWordRangeCount, new_ranges, zone);
AddUnicodeCaseEquivalents(new_ranges, zone);
if (type == 'W') {
ZoneList<CharacterRange>* negated =
new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::Negate(new_ranges, negated, zone);
new_ranges = negated;
}
ranges->AddAll(*new_ranges, zone);
return;
}
AddClassEscape(type, ranges, zone);
}
void CharacterRange::AddClassEscape(char type, ZoneList<CharacterRange>* ranges,
Zone* zone) {
switch (type) {
case 's':
AddClass(kSpaceRanges, kSpaceRangeCount, ranges, zone);
break;
case 'S':
AddClassNegated(kSpaceRanges, kSpaceRangeCount, ranges, zone);
break;
case 'w':
AddClass(kWordRanges, kWordRangeCount, ranges, zone);
break;
case 'W':
AddClassNegated(kWordRanges, kWordRangeCount, ranges, zone);
break;
case 'd':
AddClass(kDigitRanges, kDigitRangeCount, ranges, zone);
break;
case 'D':
AddClassNegated(kDigitRanges, kDigitRangeCount, ranges, zone);
break;
case '.':
AddClassNegated(kLineTerminatorRanges, kLineTerminatorRangeCount, ranges,
zone);
break;
// This is not a character range as defined by the spec but a
// convenient shorthand for a character class that matches any
// character.
case '*':
ranges->Add(CharacterRange::Everything(), zone);
break;
// This is the set of characters matched by the $ and ^ symbols
// in multiline mode.
case 'n':
AddClass(kLineTerminatorRanges, kLineTerminatorRangeCount, ranges, zone);
break;
default:
UNREACHABLE();
}
}
Vector<const int> CharacterRange::GetWordBounds() {
return Vector<const int>(kWordRanges, kWordRangeCount - 1);
}
// static
void CharacterRange::AddCaseEquivalents(Isolate* isolate, Zone* zone,
ZoneList<CharacterRange>* ranges,
bool is_one_byte) {
CharacterRange::Canonicalize(ranges);
int range_count = ranges->length();
#ifdef V8_INTL_SUPPORT
icu::UnicodeSet already_added;
icu::UnicodeSet others;
for (int i = 0; i < range_count; i++) {
CharacterRange range = ranges->at(i);
uc32 bottom = range.from();
if (bottom > String::kMaxUtf16CodeUnit) continue;
uc32 top = Min(range.to(), String::kMaxUtf16CodeUnit);
// Nothing to be done for surrogates.
if (bottom >= kLeadSurrogateStart && top <= kTrailSurrogateEnd) continue;
if (is_one_byte && !RangeContainsLatin1Equivalents(range)) {
if (bottom > String::kMaxOneByteCharCode) continue;
if (top > String::kMaxOneByteCharCode) top = String::kMaxOneByteCharCode;
}
already_added.add(bottom, top);
icu::Locale locale = icu::Locale::getRoot();
while (bottom <= top) {
icu::UnicodeString upper(bottom);
upper.toUpper(locale);
icu::UnicodeSet expanded(bottom, bottom);
expanded.closeOver(USET_CASE_INSENSITIVE);
for (int32_t i = 0; i < expanded.getRangeCount(); i++) {
UChar32 start = expanded.getRangeStart(i);
UChar32 end = expanded.getRangeEnd(i);
while (start <= end) {
icu::UnicodeString upper2(start);
upper2.toUpper(locale);
// Only add if the upper case are the same.
if (upper[0] == upper2[0]) {
// #sec-runtime-semantics-canonicalize-ch
// 3.g. If the numeric value of ch ≥ 128 and the numeric value of
// cu < 128, return ch.
if (bottom >= 128 && start < 128) {
others.add(bottom);
} else {
// 3.h. 3.h. 3.h. Return cu.
others.add(start);
}
}
start++;
}
}
bottom++;
}
}
others.removeAll(already_added);
for (int32_t i = 0; i < others.getRangeCount(); i++) {
UChar32 start = others.getRangeStart(i);
UChar32 end = others.getRangeEnd(i);
if (start == end) {
ranges->Add(CharacterRange::Singleton(start), zone);
} else {
ranges->Add(CharacterRange::Range(start, end), zone);
}
}
#else
for (int i = 0; i < range_count; i++) {
CharacterRange range = ranges->at(i);
uc32 bottom = range.from();
if (bottom > String::kMaxUtf16CodeUnit) continue;
uc32 top = Min(range.to(), String::kMaxUtf16CodeUnit);
// Nothing to be done for surrogates.
if (bottom >= kLeadSurrogateStart && top <= kTrailSurrogateEnd) continue;
if (is_one_byte && !RangeContainsLatin1Equivalents(range)) {
if (bottom > String::kMaxOneByteCharCode) continue;
if (top > String::kMaxOneByteCharCode) top = String::kMaxOneByteCharCode;
}
unibrow::uchar chars[unibrow::Ecma262UnCanonicalize::kMaxWidth];
if (top == bottom) {
// If this is a singleton we just expand the one character.
int length = isolate->jsregexp_uncanonicalize()->get(bottom, '\0', chars);
for (int i = 0; i < length; i++) {
uc32 chr = chars[i];
if (chr != bottom) {
ranges->Add(CharacterRange::Singleton(chars[i]), zone);
}
}
} else {
// If this is a range we expand the characters block by block, expanding
// contiguous subranges (blocks) one at a time. The approach is as
// follows. For a given start character we look up the remainder of the
// block that contains it (represented by the end point), for instance we
// find 'z' if the character is 'c'. A block is characterized by the
// property that all characters uncanonicalize in the same way, except
// that each entry in the result is incremented by the distance from the
// first element. So a-z is a block because 'a' uncanonicalizes to ['a',
// 'A'] and the k'th letter uncanonicalizes to ['a' + k, 'A' + k]. Once
// we've found the end point we look up its uncanonicalization and
// produce a range for each element. For instance for [c-f] we look up
// ['z', 'Z'] and produce [c-f] and [C-F]. We then only add a range if
// it is not already contained in the input, so [c-f] will be skipped but
// [C-F] will be added. If this range is not completely contained in a
// block we do this for all the blocks covered by the range (handling
// characters that is not in a block as a "singleton block").
unibrow::uchar equivalents[unibrow::Ecma262UnCanonicalize::kMaxWidth];
int pos = bottom;
while (pos <= top) {
int length =
isolate->jsregexp_canonrange()->get(pos, '\0', equivalents);
uc32 block_end;
if (length == 0) {
block_end = pos;
} else {
DCHECK_EQ(1, length);
block_end = equivalents[0];
}
int end = (block_end > top) ? top : block_end;
length = isolate->jsregexp_uncanonicalize()->get(block_end, '\0',
equivalents);
for (int i = 0; i < length; i++) {
uc32 c = equivalents[i];
uc32 range_from = c - (block_end - pos);
uc32 range_to = c - (block_end - end);
if (!(bottom <= range_from && range_to <= top)) {
ranges->Add(CharacterRange::Range(range_from, range_to), zone);
}
}
pos = end + 1;
}
}
}
#endif // V8_INTL_SUPPORT
}
bool CharacterRange::IsCanonical(ZoneList<CharacterRange>* ranges) {
DCHECK_NOT_NULL(ranges);
int n = ranges->length();
if (n <= 1) return true;
int max = ranges->at(0).to();
for (int i = 1; i < n; i++) {
CharacterRange next_range = ranges->at(i);
if (next_range.from() <= max + 1) return false;
max = next_range.to();
}
return true;
}
ZoneList<CharacterRange>* CharacterSet::ranges(Zone* zone) {
if (ranges_ == nullptr) {
ranges_ = new (zone) ZoneList<CharacterRange>(2, zone);
CharacterRange::AddClassEscape(standard_set_type_, ranges_, false, zone);
}
return ranges_;
}
// Move a number of elements in a zonelist to another position
// in the same list. Handles overlapping source and target areas.
static void MoveRanges(ZoneList<CharacterRange>* list, int from, int to,
int count) {
// Ranges are potentially overlapping.
if (from < to) {
for (int i = count - 1; i >= 0; i--) {
list->at(to + i) = list->at(from + i);
}
} else {
for (int i = 0; i < count; i++) {
list->at(to + i) = list->at(from + i);
}
}
}
static int InsertRangeInCanonicalList(ZoneList<CharacterRange>* list, int count,
CharacterRange insert) {
// Inserts a range into list[0..count[, which must be sorted
// by from value and non-overlapping and non-adjacent, using at most
// list[0..count] for the result. Returns the number of resulting
// canonicalized ranges. Inserting a range may collapse existing ranges into
// fewer ranges, so the return value can be anything in the range 1..count+1.
uc32 from = insert.from();
uc32 to = insert.to();
int start_pos = 0;
int end_pos = count;
for (int i = count - 1; i >= 0; i--) {
CharacterRange current = list->at(i);
if (current.from() > to + 1) {
end_pos = i;
} else if (current.to() + 1 < from) {
start_pos = i + 1;
break;
}
}
// Inserted range overlaps, or is adjacent to, ranges at positions
// [start_pos..end_pos[. Ranges before start_pos or at or after end_pos are
// not affected by the insertion.
// If start_pos == end_pos, the range must be inserted before start_pos.
// if start_pos < end_pos, the entire range from start_pos to end_pos
// must be merged with the insert range.
if (start_pos == end_pos) {
// Insert between existing ranges at position start_pos.
if (start_pos < count) {
MoveRanges(list, start_pos, start_pos + 1, count - start_pos);
}
list->at(start_pos) = insert;
return count + 1;
}
if (start_pos + 1 == end_pos) {
// Replace single existing range at position start_pos.
CharacterRange to_replace = list->at(start_pos);
int new_from = Min(to_replace.from(), from);
int new_to = Max(to_replace.to(), to);
list->at(start_pos) = CharacterRange::Range(new_from, new_to);
return count;
}
// Replace a number of existing ranges from start_pos to end_pos - 1.
// Move the remaining ranges down.
int new_from = Min(list->at(start_pos).from(), from);
int new_to = Max(list->at(end_pos - 1).to(), to);
if (end_pos < count) {
MoveRanges(list, end_pos, start_pos + 1, count - end_pos);
}
list->at(start_pos) = CharacterRange::Range(new_from, new_to);
return count - (end_pos - start_pos) + 1;
}
void CharacterSet::Canonicalize() {
// Special/default classes are always considered canonical. The result
// of calling ranges() will be sorted.
if (ranges_ == nullptr) return;
CharacterRange::Canonicalize(ranges_);
}
void CharacterRange::Canonicalize(ZoneList<CharacterRange>* character_ranges) {
if (character_ranges->length() <= 1) return;
// Check whether ranges are already canonical (increasing, non-overlapping,
// non-adjacent).
int n = character_ranges->length();
int max = character_ranges->at(0).to();
int i = 1;
while (i < n) {
CharacterRange current = character_ranges->at(i);
if (current.from() <= max + 1) {
break;
}
max = current.to();
i++;
}
// Canonical until the i'th range. If that's all of them, we are done.
if (i == n) return;
// The ranges at index i and forward are not canonicalized. Make them so by
// doing the equivalent of insertion sort (inserting each into the previous
// list, in order).
// Notice that inserting a range can reduce the number of ranges in the
// result due to combining of adjacent and overlapping ranges.
int read = i; // Range to insert.
int num_canonical = i; // Length of canonicalized part of list.
do {
num_canonical = InsertRangeInCanonicalList(character_ranges, num_canonical,
character_ranges->at(read));
read++;
} while (read < n);
character_ranges->Rewind(num_canonical);
DCHECK(CharacterRange::IsCanonical(character_ranges));
}
void CharacterRange::Negate(ZoneList<CharacterRange>* ranges,
ZoneList<CharacterRange>* negated_ranges,
Zone* zone) {
DCHECK(CharacterRange::IsCanonical(ranges));
DCHECK_EQ(0, negated_ranges->length());
int range_count = ranges->length();
uc32 from = 0;
int i = 0;
if (range_count > 0 && ranges->at(0).from() == 0) {
from = ranges->at(0).to() + 1;
i = 1;
}
while (i < range_count) {
CharacterRange range = ranges->at(i);
negated_ranges->Add(CharacterRange::Range(from, range.from() - 1), zone);
from = range.to() + 1;
i++;
}
if (from < String::kMaxCodePoint) {
negated_ranges->Add(CharacterRange::Range(from, String::kMaxCodePoint),
zone);
}
}
// Scoped object to keep track of how much we unroll quantifier loops in the
// regexp graph generator.
class RegExpExpansionLimiter {
public:
static const int kMaxExpansionFactor = 6;
RegExpExpansionLimiter(RegExpCompiler* compiler, int factor)
: compiler_(compiler),
saved_expansion_factor_(compiler->current_expansion_factor()),
ok_to_expand_(saved_expansion_factor_ <= kMaxExpansionFactor) {
DCHECK_LT(0, factor);
if (ok_to_expand_) {
if (factor > kMaxExpansionFactor) {
// Avoid integer overflow of the current expansion factor.
ok_to_expand_ = false;
compiler->set_current_expansion_factor(kMaxExpansionFactor + 1);
} else {
int new_factor = saved_expansion_factor_ * factor;
ok_to_expand_ = (new_factor <= kMaxExpansionFactor);
compiler->set_current_expansion_factor(new_factor);
}
}
}
~RegExpExpansionLimiter() {
compiler_->set_current_expansion_factor(saved_expansion_factor_);
}
bool ok_to_expand() { return ok_to_expand_; }
private:
RegExpCompiler* compiler_;
int saved_expansion_factor_;
bool ok_to_expand_;
DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpExpansionLimiter);
};
RegExpNode* RegExpQuantifier::ToNode(int min, int max, bool is_greedy,
RegExpTree* body, RegExpCompiler* compiler,
RegExpNode* on_success,
bool not_at_start) {
// x{f, t} becomes this:
//
// (r++)<-.
// | `
// | (x)
// v ^
// (r=0)-->(?)---/ [if r < t]
// |
// [if r >= f] \----> ...
//
// 15.10.2.5 RepeatMatcher algorithm.
// The parser has already eliminated the case where max is 0. In the case
// where max_match is zero the parser has removed the quantifier if min was
// > 0 and removed the atom if min was 0. See AddQuantifierToAtom.
// If we know that we cannot match zero length then things are a little
// simpler since we don't need to make the special zero length match check
// from step 2.1. If the min and max are small we can unroll a little in
// this case.
static const int kMaxUnrolledMinMatches = 3; // Unroll (foo)+ and (foo){3,}
static const int kMaxUnrolledMaxMatches = 3; // Unroll (foo)? and (foo){x,3}
if (max == 0) return on_success; // This can happen due to recursion.
bool body_can_be_empty = (body->min_match() == 0);
int body_start_reg = RegExpCompiler::kNoRegister;
Interval capture_registers = body->CaptureRegisters();
bool needs_capture_clearing = !capture_registers.is_empty();
Zone* zone = compiler->zone();
if (body_can_be_empty) {
body_start_reg = compiler->AllocateRegister();
} else if (compiler->optimize() && !needs_capture_clearing) {
// Only unroll if there are no captures and the body can't be
// empty.
{
RegExpExpansionLimiter limiter(compiler, min + ((max != min) ? 1 : 0));
if (min > 0 && min <= kMaxUnrolledMinMatches && limiter.ok_to_expand()) {
int new_max = (max == kInfinity) ? max : max - min;
// Recurse once to get the loop or optional matches after the fixed
// ones.
RegExpNode* answer =
ToNode(0, new_max, is_greedy, body, compiler, on_success, true);
// Unroll the forced matches from 0 to min. This can cause chains of
// TextNodes (which the parser does not generate). These should be
// combined if it turns out they hinder good code generation.
for (int i = 0; i < min; i++) {
answer = body->ToNode(compiler, answer);
}
return answer;
}
}
if (max <= kMaxUnrolledMaxMatches && min == 0) {
DCHECK_LT(0, max); // Due to the 'if' above.
RegExpExpansionLimiter limiter(compiler, max);
if (limiter.ok_to_expand()) {
// Unroll the optional matches up to max.
RegExpNode* answer = on_success;
for (int i = 0; i < max; i++) {
ChoiceNode* alternation = new (zone) ChoiceNode(2, zone);
if (is_greedy) {
alternation->AddAlternative(
GuardedAlternative(body->ToNode(compiler, answer)));
alternation->AddAlternative(GuardedAlternative(on_success));
} else {
alternation->AddAlternative(GuardedAlternative(on_success));
alternation->AddAlternative(
GuardedAlternative(body->ToNode(compiler, answer)));
}
answer = alternation;
if (not_at_start && !compiler->read_backward()) {
alternation->set_not_at_start();
}
}
return answer;
}
}
}
bool has_min = min > 0;
bool has_max = max < RegExpTree::kInfinity;
bool needs_counter = has_min || has_max;
int reg_ctr = needs_counter ? compiler->AllocateRegister()
: RegExpCompiler::kNoRegister;
LoopChoiceNode* center = new (zone)
LoopChoiceNode(body->min_match() == 0, compiler->read_backward(), zone);
if (not_at_start && !compiler->read_backward()) center->set_not_at_start();
RegExpNode* loop_return =
needs_counter ? static_cast<RegExpNode*>(
ActionNode::IncrementRegister(reg_ctr, center))
: static_cast<RegExpNode*>(center);
if (body_can_be_empty) {
// If the body can be empty we need to check if it was and then
// backtrack.
loop_return =
ActionNode::EmptyMatchCheck(body_start_reg, reg_ctr, min, loop_return);
}
RegExpNode* body_node = body->ToNode(compiler, loop_return);
if (body_can_be_empty) {
// If the body can be empty we need to store the start position
// so we can bail out if it was empty.
body_node = ActionNode::StorePosition(body_start_reg, false, body_node);
}
if (needs_capture_clearing) {
// Before entering the body of this loop we need to clear captures.
body_node = ActionNode::ClearCaptures(capture_registers, body_node);
}
GuardedAlternative body_alt(body_node);
if (has_max) {
Guard* body_guard = new (zone) Guard(reg_ctr, Guard::LT, max);
body_alt.AddGuard(body_guard, zone);
}
GuardedAlternative rest_alt(on_success);
if (has_min) {
Guard* rest_guard = new (compiler->zone()) Guard(reg_ctr, Guard::GEQ, min);
rest_alt.AddGuard(rest_guard, zone);
}
if (is_greedy) {
center->AddLoopAlternative(body_alt);
center->AddContinueAlternative(rest_alt);
} else {
center->AddContinueAlternative(rest_alt);
center->AddLoopAlternative(body_alt);
}
if (needs_counter) {
return ActionNode::SetRegister(reg_ctr, 0, center);
} else {
return center;
}
}
} // namespace internal
} // namespace v8
src/regexp/regexp-compiler.h 0 → 100644
View file @ d61a558a
// Copyright 2019 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_COMPILER_H_
#define V8_REGEXP_REGEXP_COMPILER_H_
#include "src/regexp/jsregexp.h" // TODO(jgruber): Remove if possible.
#include "src/regexp/regexp-macro-assembler-arch.h"
namespace v8 {
namespace internal {
class Isolate;
namespace regexp_compiler_constants {
// The '2' variant is has inclusive from and exclusive to.
// This covers \s as defined in ECMA-262 5.1, 15.10.2.12,
// which include WhiteSpace (7.2) or LineTerminator (7.3) values.
constexpr uc32 kRangeEndMarker = 0x110000;
constexpr int kSpaceRanges[] = {
'\t', '\r' + 1, ' ', ' ' + 1, 0x00A0, 0x00A1, 0x1680,
0x1681, 0x2000, 0x200B, 0x2028, 0x202A, 0x202F, 0x2030,
0x205F, 0x2060, 0x3000, 0x3001, 0xFEFF, 0xFF00, kRangeEndMarker};
constexpr int kSpaceRangeCount = arraysize(kSpaceRanges);
constexpr int kWordRanges[] = {'0', '9' + 1, 'A', 'Z' + 1, '_',
'_' + 1, 'a', 'z' + 1, kRangeEndMarker};
constexpr int kWordRangeCount = arraysize(kWordRanges);
constexpr int kDigitRanges[] = {'0', '9' + 1, kRangeEndMarker};
constexpr int kDigitRangeCount = arraysize(kDigitRanges);
constexpr int kSurrogateRanges[] = {kLeadSurrogateStart,
kLeadSurrogateStart + 1, kRangeEndMarker};
constexpr int kSurrogateRangeCount = arraysize(kSurrogateRanges);
constexpr int kLineTerminatorRanges[] = {0x000A, 0x000B, 0x000D, 0x000E,
0x2028, 0x202A, kRangeEndMarker};
constexpr int kLineTerminatorRangeCount = arraysize(kLineTerminatorRanges);
} // namespace regexp_compiler_constants
class FrequencyCollator {
public:
FrequencyCollator() : total_samples_(0) {
for (int i = 0; i < RegExpMacroAssembler::kTableSize; i++) {
frequencies_[i] = CharacterFrequency(i);
}
}
void CountCharacter(int character) {
int index = (character & RegExpMacroAssembler::kTableMask);
frequencies_[index].Increment();
total_samples_++;
}
// Does not measure in percent, but rather per-128 (the table size from the
// regexp macro assembler).
int Frequency(int in_character) {
DCHECK((in_character & RegExpMacroAssembler::kTableMask) == in_character);
if (total_samples_ < 1) return 1; // Division by zero.
int freq_in_per128 =
(frequencies_[in_character].counter() * 128) / total_samples_;
return freq_in_per128;
}
private:
class CharacterFrequency {
public:
CharacterFrequency() : counter_(0), character_(-1) {}
explicit CharacterFrequency(int character)
: counter_(0), character_(character) {}
void Increment() { counter_++; }
int counter() { return counter_; }
int character() { return character_; }
private:
int counter_;
int character_;
};
private:
CharacterFrequency frequencies_[RegExpMacroAssembler::kTableSize];
int total_samples_;
};
class RegExpCompiler {
public:
RegExpCompiler(Isolate* isolate, Zone* zone, int capture_count,
bool is_one_byte);
int AllocateRegister() {
if (next_register_ >= RegExpMacroAssembler::kMaxRegister) {
reg_exp_too_big_ = true;
return next_register_;
}
return next_register_++;
}
// Lookarounds to match lone surrogates for unicode character class matches
// are never nested. We can therefore reuse registers.
int UnicodeLookaroundStackRegister() {
if (unicode_lookaround_stack_register_ == kNoRegister) {
unicode_lookaround_stack_register_ = AllocateRegister();
}
return unicode_lookaround_stack_register_;
}
int UnicodeLookaroundPositionRegister() {
if (unicode_lookaround_position_register_ == kNoRegister) {
unicode_lookaround_position_register_ = AllocateRegister();
}
return unicode_lookaround_position_register_;
}
RegExpEngine::CompilationResult Assemble(Isolate* isolate,
RegExpMacroAssembler* assembler,
RegExpNode* start, int capture_count,
Handle<String> pattern);
inline void AddWork(RegExpNode* node) {
if (!node->on_work_list() && !node->label()->is_bound()) {
node->set_on_work_list(true);
work_list_->push_back(node);
}
}
static const int kImplementationOffset = 0;
static const int kNumberOfRegistersOffset = 0;
static const int kCodeOffset = 1;
RegExpMacroAssembler* macro_assembler() { return macro_assembler_; }
EndNode* accept() { return accept_; }
static const int kMaxRecursion = 100;
inline int recursion_depth() { return recursion_depth_; }
inline void IncrementRecursionDepth() { recursion_depth_++; }
inline void DecrementRecursionDepth() { recursion_depth_--; }
void SetRegExpTooBig() { reg_exp_too_big_ = true; }
inline bool one_byte() { return one_byte_; }
inline bool optimize() { return optimize_; }
inline void set_optimize(bool value) { optimize_ = value; }
inline bool limiting_recursion() { return limiting_recursion_; }
inline void set_limiting_recursion(bool value) {
limiting_recursion_ = value;
}
bool read_backward() { return read_backward_; }
void set_read_backward(bool value) { read_backward_ = value; }
FrequencyCollator* frequency_collator() { return &frequency_collator_; }
int current_expansion_factor() { return current_expansion_factor_; }
void set_current_expansion_factor(int value) {
current_expansion_factor_ = value;
}
Isolate* isolate() const { return isolate_; }
Zone* zone() const { return zone_; }
static const int kNoRegister = -1;
private:
EndNode* accept_;
int next_register_;
int unicode_lookaround_stack_register_;
int unicode_lookaround_position_register_;
std::vector<RegExpNode*>* work_list_;
int recursion_depth_;
RegExpMacroAssembler* macro_assembler_;
bool one_byte_;
bool reg_exp_too_big_;
bool limiting_recursion_;
bool optimize_;
bool read_backward_;
int current_expansion_factor_;
FrequencyCollator frequency_collator_;
Isolate* isolate_;
Zone* zone_;
};
// Categorizes character ranges into BMP, non-BMP, lead, and trail surrogates.
class UnicodeRangeSplitter {
public:
V8_EXPORT_PRIVATE UnicodeRangeSplitter(Zone* zone,
ZoneList<CharacterRange>* base);
void Call(uc32 from, DispatchTable::Entry entry);
ZoneList<CharacterRange>* bmp() { return bmp_; }
ZoneList<CharacterRange>* lead_surrogates() { return lead_surrogates_; }
ZoneList<CharacterRange>* trail_surrogates() { return trail_surrogates_; }
ZoneList<CharacterRange>* non_bmp() const { return non_bmp_; }
private:
static const int kBase = 0;
// Separate ranges into
static const int kBmpCodePoints = 1;
static const int kLeadSurrogates = 2;
static const int kTrailSurrogates = 3;
static const int kNonBmpCodePoints = 4;
Zone* zone_;
DispatchTable table_;
ZoneList<CharacterRange>* bmp_;
ZoneList<CharacterRange>* lead_surrogates_;
ZoneList<CharacterRange>* trail_surrogates_;
ZoneList<CharacterRange>* non_bmp_;
};
// We need to check for the following characters: 0x39C 0x3BC 0x178.
// TODO(jgruber): Move to CharacterRange.
bool RangeContainsLatin1Equivalents(CharacterRange range);
} // namespace internal
} // namespace v8
#endif // V8_REGEXP_REGEXP_COMPILER_H_
test/cctest/test-regexp.cc
View file @ d61a558a
...@@ -37,6 +37,7 @@ ...@@ -37,6 +37,7 @@
#include "src/init/v8.h" #include "src/init/v8.h"
#include "src/objects/objects-inl.h" #include "src/objects/objects-inl.h"
#include "src/regexp/jsregexp.h" #include "src/regexp/jsregexp.h"
#include "src/regexp/regexp-compiler.h"
#include "src/regexp/regexp-interpreter.h" #include "src/regexp/regexp-interpreter.h"
#include "src/regexp/regexp-macro-assembler-arch.h" #include "src/regexp/regexp-macro-assembler-arch.h"
#include "src/regexp/regexp-macro-assembler-irregexp.h" #include "src/regexp/regexp-macro-assembler-irregexp.h"
......
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