Index: runtime/vm/regexp.cc |
diff --git a/runtime/vm/regexp.cc b/runtime/vm/regexp.cc |
new file mode 100644 |
index 0000000000000000000000000000000000000000..6ccdbbe6afbf2c6c2dbf9f28423a3ffd7145aa46 |
--- /dev/null |
+++ b/runtime/vm/regexp.cc |
@@ -0,0 +1,4851 @@ |
+// Copyright (c) 2014, the Dart project authors. Please see the AUTHORS file |
+// for details. All rights reserved. Use of this source code is governed by a |
+// BSD-style license that can be found in the LICENSE file. |
+ |
+#include "vm/regexp.h" |
+ |
+#include "vm/dart_entry.h" |
+#include "vm/regexp_assembler.h" |
+#include "vm/regexp_ast.h" |
+#include "vm/unibrow-inl.h" |
+#include "vm/unicode.h" |
+#include "vm/symbols.h" |
+ |
+#define I isolate() |
+#define CI compiler->isolate() |
+ |
+namespace dart { |
+ |
+DECLARE_FLAG(bool, trace_irregexp); |
+ |
+#define DEFINE_ACCEPT(Type) \ |
+ void Type##Node::Accept(NodeVisitor* visitor) { \ |
+ visitor->Visit##Type(this); \ |
+ } |
+FOR_EACH_NODE_TYPE(DEFINE_ACCEPT) |
+#undef DEFINE_ACCEPT |
+ |
+ |
+// Default to generating optimized regexp code. |
+static const bool kRegexpOptimization = true; |
+ |
+// More makes code generation slower, less makes V8 benchmark score lower. |
+static const intptr_t kMaxLookaheadForBoyerMoore = 8; |
+ |
+// In a 3-character pattern you can maximally step forwards 3 characters |
+// at a time, which is not always enough to pay for the extra logic. |
+static const intptr_t kPatternTooShortForBoyerMoore = 2; |
+ |
+// The '2' variant 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 intptr_t kSpaceRanges[] = { '\t', '\r' + 1, ' ', ' ' + 1, |
+ 0x00A0, 0x00A1, 0x1680, 0x1681, 0x180E, 0x180F, 0x2000, 0x200B, |
+ 0x2028, 0x202A, 0x202F, 0x2030, 0x205F, 0x2060, 0x3000, 0x3001, |
+ 0xFEFF, 0xFF00, 0x10000 }; |
+static const intptr_t kSpaceRangeCount = ARRAY_SIZE(kSpaceRanges); |
+static const intptr_t kWordRanges[] = { |
+ '0', '9' + 1, 'A', 'Z' + 1, '_', '_' + 1, 'a', 'z' + 1, 0x10000 }; |
+static const intptr_t kWordRangeCount = ARRAY_SIZE(kWordRanges); |
+static const intptr_t kDigitRanges[] = { '0', '9' + 1, 0x10000 }; |
+static const intptr_t kDigitRangeCount = ARRAY_SIZE(kDigitRanges); |
+static const intptr_t kSurrogateRanges[] = { 0xd800, 0xe000, 0x10000 }; |
+static const intptr_t kSurrogateRangeCount = ARRAY_SIZE(kSurrogateRanges); |
+static const intptr_t kLineTerminatorRanges[] = { |
+ 0x000A, 0x000B, 0x000D, 0x000E, 0x2028, 0x202A, 0x10000 }; |
+static const intptr_t kLineTerminatorRangeCount = |
+ ARRAY_SIZE(kLineTerminatorRanges); |
+ |
+ |
+static inline void PrintUtf16(uint16_t c) { |
+ const char* format = (0x20 <= c && c <= 0x7F) ? |
+ "%c" : (c <= 0xff) ? "\\x%02x" : "\\u%04x"; |
+ OS::Print(format, c); |
+} |
+ |
+ |
+// 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(0x39c) || |
+ range.Contains(0x3bc) || range.Contains(0x178); |
+} |
+ |
+ |
+static bool RangesContainLatin1Equivalents( |
+ ZoneGrowableArray<CharacterRange>* ranges) { |
+ for (intptr_t i = 0; i < ranges->length(); i++) { |
+ // TODO(dcarney): this could be a lot more efficient. |
+ if (RangeContainsLatin1Equivalents(ranges->At(i))) return true; |
+ } |
+ return false; |
+} |
+ |
+static uint16_t ConvertNonLatin1ToLatin1(uint16_t c) { |
+ ASSERT(c > Symbols::kMaxOneCharCodeSymbol); |
+ switch (c) { |
+ // This are equivalent characters in unicode. |
+ case 0x39c: |
+ case 0x3bc: |
+ return 0xb5; |
+ // This is an uppercase of a Latin-1 character |
+ // outside of Latin-1. |
+ case 0x178: |
+ return 0xff; |
+ } |
+ return 0; |
+} |
+ |
+ |
+class VisitMarker : public ValueObject { |
+ public: |
+ explicit VisitMarker(NodeInfo* info) : info_(info) { |
+ ASSERT(!info->visited); |
+ info->visited = true; |
+ } |
+ ~VisitMarker() { |
+ info_->visited = false; |
+ } |
+ private: |
+ NodeInfo* info_; |
+}; |
+ |
+ |
+class FrequencyCollator : public ValueObject { |
+ public: |
+ FrequencyCollator() : total_samples_(0) { |
+ for (intptr_t i = 0; i < RegExpMacroAssembler::kTableSize; i++) { |
+ frequencies_[i] = CharacterFrequency(i); |
+ } |
+ } |
+ |
+ void CountCharacter(intptr_t character) { |
+ intptr_t 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). |
+ intptr_t Frequency(intptr_t in_character) { |
+ ASSERT((in_character & RegExpMacroAssembler::kTableMask) == in_character); |
+ if (total_samples_ < 1) return 1; // Division by zero. |
+ intptr_t 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(intptr_t character) |
+ : counter_(0), character_(character) { } |
+ |
+ void Increment() { counter_++; } |
+ intptr_t counter() { return counter_; } |
+ intptr_t character() { return character_; } |
+ |
+ private: |
+ intptr_t counter_; |
+ intptr_t character_; |
+ |
+ DISALLOW_ALLOCATION(); |
+ }; |
+ |
+ |
+ private: |
+ CharacterFrequency frequencies_[RegExpMacroAssembler::kTableSize]; |
+ intptr_t total_samples_; |
+}; |
+ |
+ |
+class RegExpCompiler : public ValueObject { |
+ public: |
+ RegExpCompiler(intptr_t capture_count, |
+ bool ignore_case, |
+ intptr_t specialization_cid); |
+ |
+ intptr_t AllocateRegister() { |
+ return next_register_++; |
+ } |
+ |
+ RegExpEngine::CompilationResult Assemble(IRRegExpMacroAssembler* assembler, |
+ RegExpNode* start, |
+ intptr_t capture_count, |
+ const String& pattern); |
+ |
+ inline void AddWork(RegExpNode* node) { work_list_->Add(node); } |
+ |
+ static const intptr_t kImplementationOffset = 0; |
+ static const intptr_t kNumberOfRegistersOffset = 0; |
+ static const intptr_t kCodeOffset = 1; |
+ |
+ IRRegExpMacroAssembler* macro_assembler() { return macro_assembler_; } |
+ EndNode* accept() { return accept_; } |
+ |
+ static const intptr_t kMaxRecursion = 100; |
+ inline intptr_t recursion_depth() { return recursion_depth_; } |
+ inline void IncrementRecursionDepth() { recursion_depth_++; } |
+ inline void DecrementRecursionDepth() { recursion_depth_--; } |
+ |
+ void SetRegExpTooBig() { reg_exp_too_big_ = true; } |
+ |
+ inline bool ignore_case() { return ignore_case_; } |
+ inline bool ascii() const { |
+ return (specialization_cid_ == kOneByteStringCid || |
+ specialization_cid_ == kExternalOneByteStringCid); |
+ } |
+ inline intptr_t specialization_cid() { return specialization_cid_; } |
+ FrequencyCollator* frequency_collator() { return &frequency_collator_; } |
+ |
+ intptr_t current_expansion_factor() { return current_expansion_factor_; } |
+ void set_current_expansion_factor(intptr_t value) { |
+ current_expansion_factor_ = value; |
+ } |
+ |
+ Isolate* isolate() const { return isolate_; } |
+ |
+ static const intptr_t kNoRegister = -1; |
+ |
+ private: |
+ EndNode* accept_; |
+ intptr_t next_register_; |
+ ZoneGrowableArray<RegExpNode*>* work_list_; |
+ intptr_t recursion_depth_; |
+ IRRegExpMacroAssembler* macro_assembler_; |
+ bool ignore_case_; |
+ intptr_t specialization_cid_; |
+ bool reg_exp_too_big_; |
+ intptr_t current_expansion_factor_; |
+ FrequencyCollator frequency_collator_; |
+ Isolate* isolate_; |
+}; |
+ |
+ |
+class RecursionCheck : public ValueObject { |
+ public: |
+ explicit RecursionCheck(RegExpCompiler* compiler) : compiler_(compiler) { |
+ compiler->IncrementRecursionDepth(); |
+ } |
+ ~RecursionCheck() { compiler_->DecrementRecursionDepth(); } |
+ private: |
+ RegExpCompiler* compiler_; |
+}; |
+ |
+ |
+// Scoped object to keep track of how much we unroll quantifier loops in the |
+// regexp graph generator. |
+class RegExpExpansionLimiter : public ValueObject { |
+ public: |
+ static const intptr_t kMaxExpansionFactor = 6; |
+ RegExpExpansionLimiter(RegExpCompiler* compiler, intptr_t factor) |
+ : compiler_(compiler), |
+ saved_expansion_factor_(compiler->current_expansion_factor()), |
+ ok_to_expand_(saved_expansion_factor_ <= kMaxExpansionFactor) { |
+ ASSERT(factor > 0); |
+ 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 { |
+ intptr_t 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_; |
+ intptr_t saved_expansion_factor_; |
+ bool ok_to_expand_; |
+ |
+ DISALLOW_IMPLICIT_CONSTRUCTORS(RegExpExpansionLimiter); |
+}; |
+ |
+ |
+// Node generation ------------------------------------------------------------- |
+ |
+RegExpNode* RegExpAtom::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ ZoneGrowableArray<TextElement>* elms = |
+ new(CI) ZoneGrowableArray<TextElement>(1); |
+ elms->Add(TextElement::Atom(this)); |
+ return new(CI) TextNode(elms, on_success); |
+} |
+ |
+ |
+RegExpNode* RegExpText::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ ZoneGrowableArray<TextElement>* elms = |
+ new(CI) ZoneGrowableArray<TextElement>(1); |
+ for (intptr_t i = 0; i < elements()->length(); i++) { |
+ elms->Add(elements()->At(i)); |
+ } |
+ return new(CI) TextNode(elms, on_success); |
+} |
+ |
+ |
+RegExpNode* RegExpCharacterClass::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ return new(CI) TextNode(this, on_success); |
+} |
+ |
+ |
+RegExpNode* RegExpDisjunction::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ ZoneGrowableArray<RegExpTree*>* alternatives = this->alternatives(); |
+ intptr_t length = alternatives->length(); |
+ ChoiceNode* result = |
+ new(CI) ChoiceNode(length, CI); |
+ for (intptr_t 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); |
+} |
+ |
+ |
+RegExpNode* RegExpQuantifier::ToNode(intptr_t min, |
+ intptr_t 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. |
+ // Unroll (foo)+ and (foo){3,} |
+ static const intptr_t kMaxUnrolledMinMatches = 3; |
+ // Unroll (foo)? and (foo){x,3} |
+ static const intptr_t kMaxUnrolledMaxMatches = 3; |
+ if (max == 0) return on_success; // This can happen due to recursion. |
+ bool body_can_be_empty = (body->min_match() == 0); |
+ intptr_t body_start_reg = RegExpCompiler::kNoRegister; |
+ Interval capture_registers = body->CaptureRegisters(); |
+ bool needs_capture_clearing = !capture_registers.is_empty(); |
+ Isolate* isolate = compiler->isolate(); |
+ |
+ if (body_can_be_empty) { |
+ body_start_reg = compiler->AllocateRegister(); |
+ } else if (kRegexpOptimization && !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()) { |
+ intptr_t 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 (intptr_t i = 0; i < min; i++) { |
+ answer = body->ToNode(compiler, answer); |
+ } |
+ return answer; |
+ } |
+ } |
+ if (max <= kMaxUnrolledMaxMatches && min == 0) { |
+ ASSERT(max > 0); // 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 (intptr_t i = 0; i < max; i++) { |
+ ChoiceNode* alternation = new(isolate) ChoiceNode(2, isolate); |
+ 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) 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; |
+ intptr_t reg_ctr = needs_counter |
+ ? compiler->AllocateRegister() |
+ : RegExpCompiler::kNoRegister; |
+ LoopChoiceNode* center = new(isolate) LoopChoiceNode(body->min_match() == 0, |
+ isolate); |
+ if (not_at_start) 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(isolate) Guard(reg_ctr, Guard::LT, max); |
+ body_alt.AddGuard(body_guard, isolate); |
+ } |
+ GuardedAlternative rest_alt(on_success); |
+ if (has_min) { |
+ Guard* rest_guard = new(isolate) Guard(reg_ctr, Guard::GEQ, min); |
+ rest_alt.AddGuard(rest_guard, isolate); |
+ } |
+ 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; |
+ } |
+} |
+ |
+ |
+RegExpNode* RegExpAssertion::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ switch (assertion_type()) { |
+ case START_OF_LINE: |
+ return AssertionNode::AfterNewline(on_success); |
+ case START_OF_INPUT: |
+ return AssertionNode::AtStart(on_success); |
+ case BOUNDARY: |
+ return AssertionNode::AtBoundary(on_success); |
+ case NON_BOUNDARY: |
+ return 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. |
+ intptr_t stack_pointer_register = compiler->AllocateRegister(); |
+ intptr_t position_register = compiler->AllocateRegister(); |
+ // The ChoiceNode to distinguish between a newline and end-of-input. |
+ ChoiceNode* result = new ChoiceNode(2, on_success->isolate()); |
+ // Create a newline atom. |
+ ZoneGrowableArray<CharacterRange>* newline_ranges = |
+ new ZoneGrowableArray<CharacterRange>(3); |
+ CharacterRange::AddClassEscape('n', newline_ranges); |
+ RegExpCharacterClass* newline_atom = new RegExpCharacterClass('n'); |
+ TextNode* newline_matcher = new TextNode( |
+ newline_atom, |
+ 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(CI) |
+ BackReferenceNode(RegExpCapture::StartRegister(index()), |
+ RegExpCapture::EndRegister(index()), |
+ on_success); |
+} |
+ |
+ |
+RegExpNode* RegExpEmpty::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ return on_success; |
+} |
+ |
+ |
+RegExpNode* RegExpLookahead::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ intptr_t stack_pointer_register = compiler->AllocateRegister(); |
+ intptr_t position_register = compiler->AllocateRegister(); |
+ |
+ const intptr_t registers_per_capture = 2; |
+ const intptr_t register_of_first_capture = 2; |
+ intptr_t register_count = capture_count_ * registers_per_capture; |
+ intptr_t register_start = |
+ register_of_first_capture + capture_from_ * registers_per_capture; |
+ |
+ RegExpNode* success; |
+ if (is_positive()) { |
+ RegExpNode* node = ActionNode::BeginSubmatch( |
+ stack_pointer_register, |
+ position_register, |
+ body()->ToNode( |
+ compiler, |
+ ActionNode::PositiveSubmatchSuccess(stack_pointer_register, |
+ position_register, |
+ register_count, |
+ register_start, |
+ on_success))); |
+ return node; |
+ } else { |
+ // We use a ChoiceNode for a negative lookahead because it has most of |
+ // the characteristics we need. It has the body of the lookahead as its |
+ // first alternative and the expression after the lookahead of the second |
+ // alternative. If the first alternative succeeds then the |
+ // NegativeSubmatchSuccess will unwind the stack including everything the |
+ // choice node set up and backtrack. If the first alternative fails then |
+ // the second alternative is tried, which is exactly the desired result |
+ // for a negative lookahead. The NegativeLookaheadChoiceNode is a special |
+ // ChoiceNode that knows to ignore the first exit when calculating quick |
+ // checks. |
+ |
+ GuardedAlternative body_alt( |
+ body()->ToNode( |
+ compiler, |
+ success = new(CI) NegativeSubmatchSuccess(stack_pointer_register, |
+ position_register, |
+ register_count, |
+ register_start, |
+ CI))); |
+ ChoiceNode* choice_node = |
+ new(CI) NegativeLookaheadChoiceNode(body_alt, |
+ GuardedAlternative(on_success), |
+ CI); |
+ return ActionNode::BeginSubmatch(stack_pointer_register, |
+ position_register, |
+ choice_node); |
+ } |
+} |
+ |
+ |
+RegExpNode* RegExpCapture::ToNode(RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ return ToNode(body(), index(), compiler, on_success); |
+} |
+ |
+ |
+RegExpNode* RegExpCapture::ToNode(RegExpTree* body, |
+ intptr_t index, |
+ RegExpCompiler* compiler, |
+ RegExpNode* on_success) { |
+ intptr_t start_reg = RegExpCapture::StartRegister(index); |
+ intptr_t end_reg = RegExpCapture::EndRegister(index); |
+ 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) { |
+ ZoneGrowableArray<RegExpTree*>* children = nodes(); |
+ RegExpNode* current = on_success; |
+ for (intptr_t i = children->length() - 1; i >= 0; i--) { |
+ current = children->At(i)->ToNode(compiler, current); |
+ } |
+ return current; |
+} |
+ |
+ |
+// ASCII filtering ------------------------------------------------------------- |
+ |
+ |
+RegExpNode* SeqRegExpNode::FilterSuccessor(intptr_t depth, bool ignore_case) { |
+ RegExpNode* next = on_success_->FilterASCII(depth - 1, ignore_case); |
+ if (next == NULL) return set_replacement(NULL); |
+ on_success_ = next; |
+ return set_replacement(this); |
+} |
+ |
+ |
+RegExpNode* SeqRegExpNode::FilterASCII(intptr_t depth, bool ignore_case) { |
+ if (info()->replacement_calculated) return replacement(); |
+ if (depth < 0) return this; |
+ ASSERT(!info()->visited); |
+ VisitMarker marker(info()); |
+ return FilterSuccessor(depth - 1, ignore_case); |
+} |
+ |
+ |
+RegExpNode* TextNode::FilterASCII(intptr_t depth, bool ignore_case) { |
+ if (info()->replacement_calculated) return replacement(); |
+ if (depth < 0) return this; |
+ ASSERT(!info()->visited); |
+ VisitMarker marker(info()); |
+ intptr_t element_count = elms_->length(); |
+ for (intptr_t i = 0; i < element_count; i++) { |
+ TextElement elm = elms_->At(i); |
+ if (elm.text_type() == TextElement::ATOM) { |
+ ZoneGrowableArray<uint16_t>* quarks = elm.atom()->data(); |
+ for (intptr_t j = 0; j < quarks->length(); j++) { |
+ uint16_t c = quarks->At(j); |
+ if (c <= Symbols::kMaxOneCharCodeSymbol) continue; |
+ if (!ignore_case) return set_replacement(NULL); |
+ // Here, we need to check for characters whose upper and lower cases |
+ // are outside the Latin-1 range. |
+ uint16_t converted = ConvertNonLatin1ToLatin1(c); |
+ // Character is outside Latin-1 completely |
+ if (converted == 0) return set_replacement(NULL); |
+ // Convert quark to Latin-1 in place. |
+ (*quarks)[0] = converted; |
+ } |
+ } else { |
+ ASSERT(elm.text_type() == TextElement::CHAR_CLASS); |
+ RegExpCharacterClass* cc = elm.char_class(); |
+ ZoneGrowableArray<CharacterRange>* ranges = cc->ranges(); |
+ if (!CharacterRange::IsCanonical(ranges)) { |
+ CharacterRange::Canonicalize(ranges); |
+ } |
+ // Now they are in order so we only need to look at the first. |
+ intptr_t range_count = ranges->length(); |
+ if (cc->is_negated()) { |
+ if (range_count != 0 && |
+ ranges->At(0).from() == 0 && |
+ ranges->At(0).to() >= Symbols::kMaxOneCharCodeSymbol) { |
+ // This will be handled in a later filter. |
+ if (ignore_case && RangesContainLatin1Equivalents(ranges)) continue; |
+ return set_replacement(NULL); |
+ } |
+ } else { |
+ if (range_count == 0 || |
+ ranges->At(0).from() > Symbols::kMaxOneCharCodeSymbol) { |
+ // This will be handled in a later filter. |
+ if (ignore_case && RangesContainLatin1Equivalents(ranges)) continue; |
+ return set_replacement(NULL); |
+ } |
+ } |
+ } |
+ } |
+ return FilterSuccessor(depth - 1, ignore_case); |
+} |
+ |
+ |
+RegExpNode* LoopChoiceNode::FilterASCII(intptr_t depth, bool ignore_case) { |
+ if (info()->replacement_calculated) return replacement(); |
+ if (depth < 0) return this; |
+ if (info()->visited) return this; |
+ { |
+ VisitMarker marker(info()); |
+ |
+ RegExpNode* continue_replacement = |
+ continue_node_->FilterASCII(depth - 1, ignore_case); |
+ // If we can't continue after the loop then there is no sense in doing the |
+ // loop. |
+ if (continue_replacement == NULL) return set_replacement(NULL); |
+ } |
+ |
+ return ChoiceNode::FilterASCII(depth - 1, ignore_case); |
+} |
+ |
+ |
+RegExpNode* ChoiceNode::FilterASCII(intptr_t depth, bool ignore_case) { |
+ if (info()->replacement_calculated) return replacement(); |
+ if (depth < 0) return this; |
+ if (info()->visited) return this; |
+ VisitMarker marker(info()); |
+ intptr_t choice_count = alternatives_->length(); |
+ |
+ for (intptr_t i = 0; i < choice_count; i++) { |
+ GuardedAlternative alternative = alternatives_->At(i); |
+ if (alternative.guards() != NULL && alternative.guards()->length() != 0) { |
+ set_replacement(this); |
+ return this; |
+ } |
+ } |
+ |
+ intptr_t surviving = 0; |
+ RegExpNode* survivor = NULL; |
+ for (intptr_t i = 0; i < choice_count; i++) { |
+ GuardedAlternative alternative = alternatives_->At(i); |
+ RegExpNode* replacement = |
+ alternative.node()->FilterASCII(depth - 1, ignore_case); |
+ ASSERT(replacement != this); // No missing EMPTY_MATCH_CHECK. |
+ if (replacement != NULL) { |
+ (*alternatives_)[i].set_node(replacement); |
+ surviving++; |
+ survivor = replacement; |
+ } |
+ } |
+ if (surviving < 2) return set_replacement(survivor); |
+ |
+ set_replacement(this); |
+ if (surviving == choice_count) { |
+ return this; |
+ } |
+ // Only some of the nodes survived the filtering. We need to rebuild the |
+ // alternatives list. |
+ ZoneGrowableArray<GuardedAlternative>* new_alternatives = |
+ new(I) ZoneGrowableArray<GuardedAlternative>(surviving); |
+ for (intptr_t i = 0; i < choice_count; i++) { |
+ RegExpNode* replacement = |
+ (*alternatives_)[i].node()->FilterASCII(depth - 1, ignore_case); |
+ if (replacement != NULL) { |
+ (*alternatives_)[i].set_node(replacement); |
+ new_alternatives->Add((*alternatives_)[i]); |
+ } |
+ } |
+ alternatives_ = new_alternatives; |
+ return this; |
+} |
+ |
+ |
+RegExpNode* NegativeLookaheadChoiceNode::FilterASCII(intptr_t depth, |
+ bool ignore_case) { |
+ if (info()->replacement_calculated) return replacement(); |
+ if (depth < 0) return this; |
+ if (info()->visited) return this; |
+ VisitMarker marker(info()); |
+ // Alternative 0 is the negative lookahead, alternative 1 is what comes |
+ // afterwards. |
+ RegExpNode* node = (*alternatives_)[1].node(); |
+ RegExpNode* replacement = node->FilterASCII(depth - 1, ignore_case); |
+ if (replacement == NULL) return set_replacement(NULL); |
+ (*alternatives_)[1].set_node(replacement); |
+ |
+ RegExpNode* neg_node = (*alternatives_)[0].node(); |
+ RegExpNode* neg_replacement = neg_node->FilterASCII(depth - 1, ignore_case); |
+ // If the negative lookahead is always going to fail then |
+ // we don't need to check it. |
+ if (neg_replacement == NULL) return set_replacement(replacement); |
+ (*alternatives_)[0].set_node(neg_replacement); |
+ return set_replacement(this); |
+} |
+ |
+ |
+// Code emission --------------------------------------------------------------- |
+ |
+ |
+void ChoiceNode::GenerateGuard(RegExpMacroAssembler* macro_assembler, |
+ Guard* guard, |
+ Trace* trace) { |
+ switch (guard->op()) { |
+ case Guard::LT: |
+ ASSERT(!trace->mentions_reg(guard->reg())); |
+ macro_assembler->IfRegisterGE(guard->reg(), |
+ guard->value(), |
+ trace->backtrack()); |
+ break; |
+ case Guard::GEQ: |
+ ASSERT(!trace->mentions_reg(guard->reg())); |
+ macro_assembler->IfRegisterLT(guard->reg(), |
+ guard->value(), |
+ trace->backtrack()); |
+ break; |
+ } |
+} |
+ |
+ |
+void NegativeSubmatchSuccess::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ |
+ // Omit flushing the trace. We discard the entire stack frame anyway. |
+ |
+ if (!label()->IsBound()) { |
+ // We are completely independent of the trace, since we ignore it, |
+ // so this code can be used as the generic version. |
+ assembler->BindBlock(label()); |
+ } |
+ |
+ // Throw away everything on the backtrack stack since the start |
+ // of the negative submatch and restore the character position. |
+ assembler->ReadCurrentPositionFromRegister(current_position_register_); |
+ assembler->ReadStackPointerFromRegister(stack_pointer_register_); |
+ if (clear_capture_count_ > 0) { |
+ // Clear any captures that might have been performed during the success |
+ // of the body of the negative look-ahead. |
+ intptr_t clear_capture_end = |
+ clear_capture_start_ + clear_capture_count_ - 1; |
+ assembler->ClearRegisters(clear_capture_start_, clear_capture_end); |
+ } |
+ // Now that we have unwound the stack we find at the top of the stack the |
+ // backtrack that the BeginSubmatch node got. |
+ assembler->Backtrack(); |
+} |
+ |
+ |
+bool Trace::GetStoredPosition(intptr_t reg, intptr_t* cp_offset) { |
+ ASSERT(*cp_offset == 0); |
+ for (DeferredAction* action = actions_; |
+ action != NULL; |
+ action = action->next()) { |
+ if (action->Mentions(reg)) { |
+ if (action->action_type() == ActionNode::STORE_POSITION) { |
+ *cp_offset = static_cast<DeferredCapture*>(action)->cp_offset(); |
+ return true; |
+ } else { |
+ return false; |
+ } |
+ } |
+ } |
+ return false; |
+} |
+ |
+ |
+// This is called as we come into a loop choice node and some other tricky |
+// nodes. It normalizes the state of the code generator to ensure we can |
+// generate generic code. |
+intptr_t Trace::FindAffectedRegisters(OutSet* affected_registers, |
+ Isolate* isolate) { |
+ intptr_t max_register = RegExpCompiler::kNoRegister; |
+ for (DeferredAction* action = actions_; |
+ action != NULL; |
+ action = action->next()) { |
+ if (action->action_type() == ActionNode::CLEAR_CAPTURES) { |
+ Interval range = static_cast<DeferredClearCaptures*>(action)->range(); |
+ for (intptr_t i = range.from(); i <= range.to(); i++) |
+ affected_registers->Set(i, isolate); |
+ if (range.to() > max_register) max_register = range.to(); |
+ } else { |
+ affected_registers->Set(action->reg(), isolate); |
+ if (action->reg() > max_register) max_register = action->reg(); |
+ } |
+ } |
+ return max_register; |
+} |
+ |
+ |
+bool Trace::DeferredAction::Mentions(intptr_t that) { |
+ if (action_type() == ActionNode::CLEAR_CAPTURES) { |
+ Interval range = static_cast<DeferredClearCaptures*>(this)->range(); |
+ return range.Contains(that); |
+ } else { |
+ return reg() == that; |
+ } |
+} |
+ |
+ |
+bool Trace::mentions_reg(intptr_t reg) { |
+ for (DeferredAction* action = actions_; |
+ action != NULL; |
+ action = action->next()) { |
+ if (action->Mentions(reg)) |
+ return true; |
+ } |
+ return false; |
+} |
+ |
+ |
+void Trace::RestoreAffectedRegisters(RegExpMacroAssembler* assembler, |
+ intptr_t max_register, |
+ const OutSet& registers_to_pop, |
+ const OutSet& registers_to_clear) { |
+ for (intptr_t reg = max_register; reg >= 0; reg--) { |
+ if (registers_to_pop.Get(reg)) { |
+ assembler->PopRegister(reg); |
+ } else if (registers_to_clear.Get(reg)) { |
+ intptr_t clear_to = reg; |
+ while (reg > 0 && registers_to_clear.Get(reg - 1)) { |
+ reg--; |
+ } |
+ assembler->ClearRegisters(reg, clear_to); |
+ } |
+ } |
+} |
+ |
+ |
+void Trace::PerformDeferredActions(RegExpMacroAssembler* assembler, |
+ intptr_t max_register, |
+ const OutSet& affected_registers, |
+ OutSet* registers_to_pop, |
+ OutSet* registers_to_clear, |
+ Isolate* isolate) { |
+ for (intptr_t reg = 0; reg <= max_register; reg++) { |
+ if (!affected_registers.Get(reg)) { |
+ continue; |
+ } |
+ |
+ // The chronologically first deferred action in the trace |
+ // is used to infer the action needed to restore a register |
+ // to its previous state (or not, if it's safe to ignore it). |
+ enum DeferredActionUndoType { IGNORE, RESTORE, CLEAR }; |
+ DeferredActionUndoType undo_action = IGNORE; |
+ |
+ intptr_t value = 0; |
+ bool absolute = false; |
+ bool clear = false; |
+ intptr_t store_position = -1; |
+ // This is a little tricky because we are scanning the actions in reverse |
+ // historical order (newest first). |
+ for (DeferredAction* action = actions_; |
+ action != NULL; |
+ action = action->next()) { |
+ if (action->Mentions(reg)) { |
+ switch (action->action_type()) { |
+ case ActionNode::SET_REGISTER: { |
+ Trace::DeferredSetRegister* psr = |
+ static_cast<Trace::DeferredSetRegister*>(action); |
+ if (!absolute) { |
+ value += psr->value(); |
+ absolute = true; |
+ } |
+ // SET_REGISTER is currently only used for newly introduced loop |
+ // counters. They can have a significant previous value if they |
+ // occour in a loop. TODO(lrn): Propagate this information, so |
+ // we can set undo_action to IGNORE if we know there is no value to |
+ // restore. |
+ undo_action = RESTORE; |
+ ASSERT(store_position == -1); |
+ ASSERT(!clear); |
+ break; |
+ } |
+ case ActionNode::INCREMENT_REGISTER: |
+ if (!absolute) { |
+ value++; |
+ } |
+ ASSERT(store_position == -1); |
+ ASSERT(!clear); |
+ undo_action = RESTORE; |
+ break; |
+ case ActionNode::STORE_POSITION: { |
+ Trace::DeferredCapture* pc = |
+ static_cast<Trace::DeferredCapture*>(action); |
+ if (!clear && store_position == -1) { |
+ store_position = pc->cp_offset(); |
+ } |
+ |
+ // For captures we know that stores and clears alternate. |
+ // Other register, are never cleared, and if the occur |
+ // inside a loop, they might be assigned more than once. |
+ if (reg <= 1) { |
+ // Registers zero and one, aka "capture zero", is |
+ // always set correctly if we succeed. There is no |
+ // need to undo a setting on backtrack, because we |
+ // will set it again or fail. |
+ undo_action = IGNORE; |
+ } else { |
+ undo_action = pc->is_capture() ? CLEAR : RESTORE; |
+ } |
+ ASSERT(!absolute); |
+ ASSERT(value == 0); |
+ break; |
+ } |
+ case ActionNode::CLEAR_CAPTURES: { |
+ // Since we're scanning in reverse order, if we've already |
+ // set the position we have to ignore historically earlier |
+ // clearing operations. |
+ if (store_position == -1) { |
+ clear = true; |
+ } |
+ undo_action = RESTORE; |
+ ASSERT(!absolute); |
+ ASSERT(value == 0); |
+ break; |
+ } |
+ default: |
+ UNREACHABLE(); |
+ break; |
+ } |
+ } |
+ } |
+ // Prepare for the undo-action (e.g., push if it's going to be popped). |
+ if (undo_action == RESTORE) { |
+ assembler->PushRegister(reg); |
+ registers_to_pop->Set(reg, isolate); |
+ } else if (undo_action == CLEAR) { |
+ registers_to_clear->Set(reg, isolate); |
+ } |
+ // Perform the chronologically last action (or accumulated increment) |
+ // for the register. |
+ if (store_position != -1) { |
+ assembler->WriteCurrentPositionToRegister(reg, store_position); |
+ } else if (clear) { |
+ assembler->ClearRegisters(reg, reg); |
+ } else if (absolute) { |
+ assembler->SetRegister(reg, value); |
+ } else if (value != 0) { |
+ assembler->AdvanceRegister(reg, value); |
+ } |
+ } |
+} |
+ |
+ |
+void Trace::Flush(RegExpCompiler* compiler, RegExpNode* successor) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ |
+ ASSERT(!is_trivial()); |
+ |
+ if (actions_ == NULL && backtrack() == NULL) { |
+ // Here we just have some deferred cp advances to fix and we are back to |
+ // a normal situation. We may also have to forget some information gained |
+ // through a quick check that was already performed. |
+ if (cp_offset_ != 0) assembler->AdvanceCurrentPosition(cp_offset_); |
+ // Create a new trivial state and generate the node with that. |
+ Trace new_state; |
+ successor->Emit(compiler, &new_state); |
+ return; |
+ } |
+ |
+ // Generate deferred actions here along with code to undo them again. |
+ OutSet affected_registers; |
+ |
+ if (backtrack() != NULL) { |
+ // Here we have a concrete backtrack location. These are set up by choice |
+ // nodes and so they indicate that we have a deferred save of the current |
+ // position which we may need to emit here. |
+ assembler->PushCurrentPosition(); |
+ } |
+ |
+ intptr_t max_register = FindAffectedRegisters(&affected_registers, CI); |
+ OutSet registers_to_pop; |
+ OutSet registers_to_clear; |
+ PerformDeferredActions(assembler, |
+ max_register, |
+ affected_registers, |
+ ®isters_to_pop, |
+ ®isters_to_clear, |
+ CI); |
+ if (cp_offset_ != 0) { |
+ assembler->AdvanceCurrentPosition(cp_offset_); |
+ } |
+ |
+ // Create a new trivial state and generate the node with that. |
+ BlockLabel undo; |
+ assembler->PushBacktrack(&undo); |
+ Trace new_state; |
+ successor->Emit(compiler, &new_state); |
+ |
+ // On backtrack we need to restore state. |
+ assembler->BindBlock(&undo); |
+ RestoreAffectedRegisters(assembler, |
+ max_register, |
+ registers_to_pop, |
+ registers_to_clear); |
+ if (backtrack() == NULL) { |
+ assembler->Backtrack(); |
+ } else { |
+ assembler->PopCurrentPosition(); |
+ assembler->GoTo(backtrack()); |
+ } |
+} |
+ |
+ |
+void Trace::InvalidateCurrentCharacter() { |
+ characters_preloaded_ = 0; |
+} |
+ |
+ |
+void Trace::AdvanceCurrentPositionInTrace(intptr_t by, |
+ RegExpCompiler* compiler) { |
+ ASSERT(by > 0); |
+ // We don't have an instruction for shifting the current character register |
+ // down or for using a shifted value for anything so lets just forget that |
+ // we preloaded any characters into it. |
+ characters_preloaded_ = 0; |
+ // Adjust the offsets of the quick check performed information. This |
+ // information is used to find out what we already determined about the |
+ // characters by means of mask and compare. |
+ quick_check_performed_.Advance(by, compiler->ascii()); |
+ cp_offset_ += by; |
+ if (cp_offset_ > RegExpMacroAssembler::kMaxCPOffset) { |
+ compiler->SetRegExpTooBig(); |
+ cp_offset_ = 0; |
+ } |
+ bound_checked_up_to_ = Utils::Maximum(static_cast<intptr_t>(0), |
+ bound_checked_up_to_ - by); |
+} |
+ |
+ |
+void EndNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ if (!trace->is_trivial()) { |
+ trace->Flush(compiler, this); |
+ return; |
+ } |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ if (!label()->IsBound()) { |
+ assembler->BindBlock(label()); |
+ } |
+ switch (action_) { |
+ case ACCEPT: |
+ assembler->Succeed(); |
+ return; |
+ case BACKTRACK: |
+ assembler->GoTo(trace->backtrack()); |
+ return; |
+ case NEGATIVE_SUBMATCH_SUCCESS: |
+ // This case is handled in a different virtual method. |
+ UNREACHABLE(); |
+ } |
+ UNIMPLEMENTED(); |
+} |
+ |
+ |
+bool QuickCheckDetails::Rationalize(bool asc) { |
+ bool found_useful_op = false; |
+ uint32_t char_mask; |
+ if (asc) { |
+ char_mask = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ char_mask = Utf16::kMaxCodeUnit; |
+ } |
+ mask_ = 0; |
+ value_ = 0; |
+ intptr_t char_shift = 0; |
+ for (intptr_t i = 0; i < characters_; i++) { |
+ Position* pos = &positions_[i]; |
+ if ((pos->mask & Symbols::kMaxOneCharCodeSymbol) != 0) { |
+ found_useful_op = true; |
+ } |
+ mask_ |= (pos->mask & char_mask) << char_shift; |
+ value_ |= (pos->value & char_mask) << char_shift; |
+ char_shift += asc ? 8 : 16; |
+ } |
+ return found_useful_op; |
+} |
+ |
+ |
+bool RegExpNode::EmitQuickCheck(RegExpCompiler* compiler, |
+ Trace* trace, |
+ bool preload_has_checked_bounds, |
+ BlockLabel* on_possible_success, |
+ QuickCheckDetails* details, |
+ bool fall_through_on_failure) { |
+ if (details->characters() == 0) return false; |
+ GetQuickCheckDetails( |
+ details, compiler, 0, trace->at_start() == Trace::FALSE_VALUE); |
+ if (details->cannot_match()) return false; |
+ if (!details->Rationalize(compiler->ascii())) return false; |
+ ASSERT(details->characters() == 1 || |
+ compiler->macro_assembler()->CanReadUnaligned()); |
+ uint32_t mask = details->mask(); |
+ uint32_t value = details->value(); |
+ |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ |
+ if (trace->characters_preloaded() != details->characters()) { |
+ assembler->LoadCurrentCharacter(trace->cp_offset(), |
+ trace->backtrack(), |
+ !preload_has_checked_bounds, |
+ details->characters()); |
+ } |
+ |
+ |
+ bool need_mask = true; |
+ |
+ if (details->characters() == 1) { |
+ // If number of characters preloaded is 1 then we used a byte or 16 bit |
+ // load so the value is already masked down. |
+ uint32_t char_mask; |
+ if (compiler->ascii()) { |
+ char_mask = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ char_mask = Utf16::kMaxCodeUnit; |
+ } |
+ if ((mask & char_mask) == char_mask) need_mask = false; |
+ mask &= char_mask; |
+ } else { |
+ // For 2-character preloads in ASCII mode or 1-character preloads in |
+ // TWO_BYTE mode we also use a 16 bit load with zero extend. |
+ if (details->characters() == 2 && compiler->ascii()) { |
+ if ((mask & 0xffff) == 0xffff) need_mask = false; |
+ } else if (details->characters() == 1 && !compiler->ascii()) { |
+ if ((mask & 0xffff) == 0xffff) need_mask = false; |
+ } else { |
+ if (mask == 0xffffffff) need_mask = false; |
+ } |
+ } |
+ |
+ if (fall_through_on_failure) { |
+ if (need_mask) { |
+ assembler->CheckCharacterAfterAnd(value, mask, on_possible_success); |
+ } else { |
+ assembler->CheckCharacter(value, on_possible_success); |
+ } |
+ } else { |
+ if (need_mask) { |
+ assembler->CheckNotCharacterAfterAnd(value, mask, trace->backtrack()); |
+ } else { |
+ assembler->CheckNotCharacter(value, trace->backtrack()); |
+ } |
+ } |
+ return true; |
+} |
+ |
+ |
+// Emit the code to check for a ^ in multiline mode (1-character lookbehind |
+// that matches newline or the start of input). |
+static void EmitHat(RegExpCompiler* compiler, |
+ RegExpNode* on_success, |
+ Trace* trace) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ // We will be loading the previous character into the current character |
+ // register. |
+ Trace new_trace(*trace); |
+ new_trace.InvalidateCurrentCharacter(); |
+ |
+ BlockLabel ok; |
+ if (new_trace.cp_offset() == 0) { |
+ // The start of input counts as a newline in this context, so skip to |
+ // ok if we are at the start. |
+ assembler->CheckAtStart(&ok); |
+ } |
+ // We already checked that we are not at the start of input so it must be |
+ // OK to load the previous character. |
+ assembler->LoadCurrentCharacter(new_trace.cp_offset() -1, |
+ new_trace.backtrack(), |
+ false); |
+ if (!assembler->CheckSpecialCharacterClass('n', |
+ new_trace.backtrack())) { |
+ // Newline means \n, \r, 0x2028 or 0x2029. |
+ if (!compiler->ascii()) { |
+ assembler->CheckCharacterAfterAnd(0x2028, 0xfffe, &ok); |
+ } |
+ assembler->CheckCharacter('\n', &ok); |
+ assembler->CheckNotCharacter('\r', new_trace.backtrack()); |
+ } |
+ assembler->BindBlock(&ok); |
+ on_success->Emit(compiler, &new_trace); |
+} |
+ |
+ |
+void AssertionNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ switch (assertion_type_) { |
+ case AT_END: { |
+ BlockLabel ok; |
+ assembler->CheckPosition(trace->cp_offset(), &ok); |
+ assembler->GoTo(trace->backtrack()); |
+ assembler->BindBlock(&ok); |
+ break; |
+ } |
+ case AT_START: { |
+ if (trace->at_start() == Trace::FALSE_VALUE) { |
+ assembler->GoTo(trace->backtrack()); |
+ return; |
+ } |
+ if (trace->at_start() == Trace::UNKNOWN) { |
+ assembler->CheckNotAtStart(trace->backtrack()); |
+ Trace at_start_trace = *trace; |
+ at_start_trace.set_at_start(true); |
+ on_success()->Emit(compiler, &at_start_trace); |
+ return; |
+ } |
+ } |
+ break; |
+ case AFTER_NEWLINE: |
+ EmitHat(compiler, on_success(), trace); |
+ return; |
+ case AT_BOUNDARY: |
+ case AT_NON_BOUNDARY: { |
+ EmitBoundaryCheck(compiler, trace); |
+ return; |
+ } |
+ } |
+ on_success()->Emit(compiler, trace); |
+} |
+ |
+ |
+RegExpNode::LimitResult RegExpNode::LimitVersions(RegExpCompiler* compiler, |
+ Trace* trace) { |
+ // If we are generating a greedy loop then don't stop and don't reuse code. |
+ if (trace->stop_node() != NULL) { |
+ return CONTINUE; |
+ } |
+ |
+ RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
+ if (trace->is_trivial()) { |
+ if (label_.IsBound()) { |
+ // We are being asked to generate a generic version, but that's already |
+ // been done so just go to it. |
+ macro_assembler->GoTo(&label_); |
+ return DONE; |
+ } |
+ if (compiler->recursion_depth() >= RegExpCompiler::kMaxRecursion) { |
+ // To avoid too deep recursion we push the node to the work queue and just |
+ // generate a goto here. |
+ compiler->AddWork(this); |
+ macro_assembler->GoTo(&label_); |
+ return DONE; |
+ } |
+ // Generate generic version of the node and bind the label for later use. |
+ macro_assembler->BindBlock(&label_); |
+ return CONTINUE; |
+ } |
+ |
+ // We are being asked to make a non-generic version. Keep track of how many |
+ // non-generic versions we generate so as not to overdo it. |
+ trace_count_++; |
+ if (kRegexpOptimization && |
+ trace_count_ < kMaxCopiesCodeGenerated && |
+ compiler->recursion_depth() <= RegExpCompiler::kMaxRecursion) { |
+ return CONTINUE; |
+ } |
+ |
+ // If we get here code has been generated for this node too many times or |
+ // recursion is too deep. Time to switch to a generic version. The code for |
+ // generic versions above can handle deep recursion properly. |
+ trace->Flush(compiler, this); |
+ return DONE; |
+} |
+ |
+ |
+// This generates the code to match a text node. A text node can contain |
+// straight character sequences (possibly to be matched in a case-independent |
+// way) and character classes. For efficiency we do not do this in a single |
+// pass from left to right. Instead we pass over the text node several times, |
+// emitting code for some character positions every time. See the comment on |
+// TextEmitPass for details. |
+void TextNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ LimitResult limit_result = LimitVersions(compiler, trace); |
+ if (limit_result == DONE) return; |
+ ASSERT(limit_result == CONTINUE); |
+ |
+ if (trace->cp_offset() + Length() > RegExpMacroAssembler::kMaxCPOffset) { |
+ compiler->SetRegExpTooBig(); |
+ return; |
+ } |
+ |
+ if (compiler->ascii()) { |
+ intptr_t dummy = 0; |
+ TextEmitPass(compiler, NON_ASCII_MATCH, false, trace, false, &dummy); |
+ } |
+ |
+ bool first_elt_done = false; |
+ intptr_t bound_checked_to = trace->cp_offset() - 1; |
+ bound_checked_to += trace->bound_checked_up_to(); |
+ |
+ // If a character is preloaded into the current character register then |
+ // check that now. |
+ if (trace->characters_preloaded() == 1) { |
+ for (intptr_t pass = kFirstRealPass; pass <= kLastPass; pass++) { |
+ if (!SkipPass(pass, compiler->ignore_case())) { |
+ TextEmitPass(compiler, |
+ static_cast<TextEmitPassType>(pass), |
+ true, |
+ trace, |
+ false, |
+ &bound_checked_to); |
+ } |
+ } |
+ first_elt_done = true; |
+ } |
+ |
+ for (intptr_t pass = kFirstRealPass; pass <= kLastPass; pass++) { |
+ if (!SkipPass(pass, compiler->ignore_case())) { |
+ TextEmitPass(compiler, |
+ static_cast<TextEmitPassType>(pass), |
+ false, |
+ trace, |
+ first_elt_done, |
+ &bound_checked_to); |
+ } |
+ } |
+ |
+ Trace successor_trace(*trace); |
+ successor_trace.set_at_start(false); |
+ successor_trace.AdvanceCurrentPositionInTrace(Length(), compiler); |
+ RecursionCheck rc(compiler); |
+ on_success()->Emit(compiler, &successor_trace); |
+} |
+ |
+ |
+void LoopChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
+ if (trace->stop_node() == this) { |
+ intptr_t text_length = |
+ GreedyLoopTextLengthForAlternative(&((*alternatives_)[0])); |
+ ASSERT(text_length != kNodeIsTooComplexForGreedyLoops); |
+ // Update the counter-based backtracking info on the stack. This is an |
+ // optimization for greedy loops (see below). |
+ ASSERT(trace->cp_offset() == text_length); |
+ macro_assembler->AdvanceCurrentPosition(text_length); |
+ macro_assembler->GoTo(trace->loop_label()); |
+ return; |
+ } |
+ ASSERT(trace->stop_node() == NULL); |
+ if (!trace->is_trivial()) { |
+ trace->Flush(compiler, this); |
+ return; |
+ } |
+ ChoiceNode::Emit(compiler, trace); |
+} |
+ |
+ |
+// This class is used when generating the alternatives in a choice node. It |
+// records the way the alternative is being code generated. |
+struct AlternativeGeneration { |
+ AlternativeGeneration() |
+ : possible_success(), |
+ expects_preload(false), |
+ after(), |
+ quick_check_details() { } |
+ BlockLabel possible_success; |
+ bool expects_preload; |
+ BlockLabel after; |
+ QuickCheckDetails quick_check_details; |
+}; |
+ |
+ |
+// Creates a list of AlternativeGenerations. If the list has a reasonable |
+// size then it is on the stack, otherwise the excess is on the heap. |
+class AlternativeGenerationList { |
+ public: |
+ explicit AlternativeGenerationList(intptr_t count) |
+ : alt_gens_(count) { |
+ for (intptr_t i = 0; i < count && i < kAFew; i++) { |
+ alt_gens_.Add(a_few_alt_gens_ + i); |
+ } |
+ for (intptr_t i = kAFew; i < count; i++) { |
+ alt_gens_.Add(new AlternativeGeneration()); |
+ } |
+ } |
+ ~AlternativeGenerationList() { |
+ for (intptr_t i = kAFew; i < alt_gens_.length(); i++) { |
+ delete alt_gens_[i]; |
+ alt_gens_[i] = NULL; |
+ } |
+ } |
+ |
+ AlternativeGeneration* at(intptr_t i) { |
+ return alt_gens_[i]; |
+ } |
+ |
+ private: |
+ static const intptr_t kAFew = 10; |
+ GrowableArray<AlternativeGeneration*> alt_gens_; |
+ AlternativeGeneration a_few_alt_gens_[kAFew]; |
+ |
+ DISALLOW_ALLOCATION(); |
+}; |
+ |
+ |
+void ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
+ intptr_t choice_count = alternatives_->length(); |
+ |
+#ifdef DEBUG |
+ for (intptr_t i = 0; i < choice_count - 1; i++) { |
+ GuardedAlternative alternative = alternatives_->At(i); |
+ ZoneGrowableArray<Guard*>* guards = alternative.guards(); |
+ intptr_t guard_count = (guards == NULL) ? 0 : guards->length(); |
+ for (intptr_t j = 0; j < guard_count; j++) { |
+ ASSERT(!trace->mentions_reg(guards->At(j)->reg())); |
+ } |
+ } |
+#endif |
+ |
+ LimitResult limit_result = LimitVersions(compiler, trace); |
+ if (limit_result == DONE) return; |
+ ASSERT(limit_result == CONTINUE); |
+ |
+ intptr_t new_flush_budget = trace->flush_budget() / choice_count; |
+ if (trace->flush_budget() == 0 && trace->actions() != NULL) { |
+ trace->Flush(compiler, this); |
+ return; |
+ } |
+ |
+ RecursionCheck rc(compiler); |
+ |
+ Trace* current_trace = trace; |
+ |
+ intptr_t text_length = |
+ GreedyLoopTextLengthForAlternative(&((*alternatives_)[0])); |
+ bool greedy_loop = false; |
+ BlockLabel greedy_loop_label; |
+ Trace counter_backtrack_trace; |
+ counter_backtrack_trace.set_backtrack(&greedy_loop_label); |
+ if (not_at_start()) counter_backtrack_trace.set_at_start(false); |
+ |
+ if (choice_count > 1 && text_length != kNodeIsTooComplexForGreedyLoops) { |
+ // Here we have special handling for greedy loops containing only text nodes |
+ // and other simple nodes. These are handled by pushing the current |
+ // position on the stack and then incrementing the current position each |
+ // time around the switch. On backtrack we decrement the current position |
+ // and check it against the pushed value. This avoids pushing backtrack |
+ // information for each iteration of the loop, which could take up a lot of |
+ // space. |
+ greedy_loop = true; |
+ ASSERT(trace->stop_node() == NULL); |
+ macro_assembler->PushCurrentPosition(); |
+ current_trace = &counter_backtrack_trace; |
+ BlockLabel greedy_match_failed; |
+ Trace greedy_match_trace; |
+ if (not_at_start()) greedy_match_trace.set_at_start(false); |
+ greedy_match_trace.set_backtrack(&greedy_match_failed); |
+ BlockLabel loop_label; |
+ macro_assembler->BindBlock(&loop_label); |
+ greedy_match_trace.set_stop_node(this); |
+ greedy_match_trace.set_loop_label(&loop_label); |
+ (*alternatives_)[0].node()->Emit(compiler, &greedy_match_trace); |
+ macro_assembler->BindBlock(&greedy_match_failed); |
+ } |
+ |
+ BlockLabel second_choice; // For use in greedy matches. |
+ macro_assembler->BindBlock(&second_choice); |
+ |
+ intptr_t first_normal_choice = greedy_loop ? 1 : 0; |
+ |
+ bool not_at_start = current_trace->at_start() == Trace::FALSE_VALUE; |
+ const intptr_t kEatsAtLeastNotYetInitialized = -1; |
+ intptr_t eats_at_least = kEatsAtLeastNotYetInitialized; |
+ |
+ bool skip_was_emitted = false; |
+ |
+ if (!greedy_loop && choice_count == 2) { |
+ GuardedAlternative alt1 = (*alternatives_)[1]; |
+ if (alt1.guards() == NULL || alt1.guards()->length() == 0) { |
+ RegExpNode* eats_anything_node = alt1.node(); |
+ if (eats_anything_node->GetSuccessorOfOmnivorousTextNode(compiler) == |
+ this) { |
+ // At this point we know that we are at a non-greedy loop that will eat |
+ // any character one at a time. Any non-anchored regexp has such a |
+ // loop prepended to it in order to find where it starts. We look for |
+ // a pattern of the form ...abc... where we can look 6 characters ahead |
+ // and step forwards 3 if the character is not one of abc. Abc need |
+ // not be atoms, they can be any reasonably limited character class or |
+ // small alternation. |
+ ASSERT(trace->is_trivial()); // This is the case on LoopChoiceNodes. |
+ BoyerMooreLookahead* lookahead = bm_info(not_at_start); |
+ if (lookahead == NULL) { |
+ eats_at_least = Utils::Minimum(kMaxLookaheadForBoyerMoore, |
+ EatsAtLeast(kMaxLookaheadForBoyerMoore, |
+ kRecursionBudget, |
+ not_at_start)); |
+ if (eats_at_least >= 1) { |
+ BoyerMooreLookahead* bm = |
+ new(I) BoyerMooreLookahead(eats_at_least, compiler, I); |
+ GuardedAlternative alt0 = alternatives_->At(0); |
+ alt0.node()->FillInBMInfo(0, kRecursionBudget, bm, not_at_start); |
+ skip_was_emitted = bm->EmitSkipInstructions(macro_assembler); |
+ } |
+ } else { |
+ skip_was_emitted = lookahead->EmitSkipInstructions(macro_assembler); |
+ } |
+ } |
+ } |
+ } |
+ |
+ if (eats_at_least == kEatsAtLeastNotYetInitialized) { |
+ // Save some time by looking at most one machine word ahead. |
+ eats_at_least = |
+ EatsAtLeast(compiler->ascii() ? 4 : 2, kRecursionBudget, not_at_start); |
+ } |
+ intptr_t preload_characters = |
+ CalculatePreloadCharacters(compiler, eats_at_least); |
+ |
+ bool preload_is_current = !skip_was_emitted && |
+ (current_trace->characters_preloaded() == preload_characters); |
+ bool preload_has_checked_bounds = preload_is_current; |
+ |
+ AlternativeGenerationList alt_gens(choice_count); |
+ |
+ // For now we just call all choices one after the other. The idea ultimately |
+ // is to use the Dispatch table to try only the relevant ones. |
+ for (intptr_t i = first_normal_choice; i < choice_count; i++) { |
+ GuardedAlternative alternative = alternatives_->At(i); |
+ AlternativeGeneration* alt_gen = alt_gens.at(i); |
+ alt_gen->quick_check_details.set_characters(preload_characters); |
+ ZoneGrowableArray<Guard*>* guards = alternative.guards(); |
+ intptr_t guard_count = (guards == NULL) ? 0 : guards->length(); |
+ Trace new_trace(*current_trace); |
+ new_trace.set_characters_preloaded(preload_is_current ? |
+ preload_characters : |
+ 0); |
+ if (preload_has_checked_bounds) { |
+ new_trace.set_bound_checked_up_to(preload_characters); |
+ } |
+ new_trace.quick_check_performed()->Clear(); |
+ if (not_at_start_) new_trace.set_at_start(Trace::FALSE_VALUE); |
+ alt_gen->expects_preload = preload_is_current; |
+ bool generate_full_check_inline = false; |
+ if (kRegexpOptimization && |
+ try_to_emit_quick_check_for_alternative(i) && |
+ alternative.node()->EmitQuickCheck(compiler, |
+ &new_trace, |
+ preload_has_checked_bounds, |
+ &alt_gen->possible_success, |
+ &alt_gen->quick_check_details, |
+ i < choice_count - 1)) { |
+ // Quick check was generated for this choice. |
+ preload_is_current = true; |
+ preload_has_checked_bounds = true; |
+ // On the last choice in the ChoiceNode we generated the quick |
+ // check to fall through on possible success. So now we need to |
+ // generate the full check inline. |
+ if (i == choice_count - 1) { |
+ macro_assembler->BindBlock(&alt_gen->possible_success); |
+ new_trace.set_quick_check_performed(&alt_gen->quick_check_details); |
+ new_trace.set_characters_preloaded(preload_characters); |
+ new_trace.set_bound_checked_up_to(preload_characters); |
+ generate_full_check_inline = true; |
+ } |
+ } else if (alt_gen->quick_check_details.cannot_match()) { |
+ if (i == choice_count - 1 && !greedy_loop) { |
+ macro_assembler->GoTo(trace->backtrack()); |
+ } |
+ continue; |
+ } else { |
+ // No quick check was generated. Put the full code here. |
+ // If this is not the first choice then there could be slow checks from |
+ // previous cases that go here when they fail. There's no reason to |
+ // insist that they preload characters since the slow check we are about |
+ // to generate probably can't use it. |
+ if (i != first_normal_choice) { |
+ alt_gen->expects_preload = false; |
+ new_trace.InvalidateCurrentCharacter(); |
+ } |
+ if (i < choice_count - 1) { |
+ new_trace.set_backtrack(&alt_gen->after); |
+ } |
+ generate_full_check_inline = true; |
+ } |
+ if (generate_full_check_inline) { |
+ if (new_trace.actions() != NULL) { |
+ new_trace.set_flush_budget(new_flush_budget); |
+ } |
+ for (intptr_t j = 0; j < guard_count; j++) { |
+ GenerateGuard(macro_assembler, guards->At(j), &new_trace); |
+ } |
+ alternative.node()->Emit(compiler, &new_trace); |
+ preload_is_current = false; |
+ } |
+ macro_assembler->BindBlock(&alt_gen->after); |
+ } |
+ if (greedy_loop) { |
+ macro_assembler->BindBlock(&greedy_loop_label); |
+ // If we have unwound to the bottom then backtrack. |
+ macro_assembler->CheckGreedyLoop(trace->backtrack()); |
+ // Otherwise try the second priority at an earlier position. |
+ macro_assembler->AdvanceCurrentPosition(-text_length); |
+ macro_assembler->GoTo(&second_choice); |
+ } |
+ |
+ // At this point we need to generate slow checks for the alternatives where |
+ // the quick check was inlined. We can recognize these because the associated |
+ // label was bound. |
+ for (intptr_t i = first_normal_choice; i < choice_count - 1; i++) { |
+ AlternativeGeneration* alt_gen = alt_gens.at(i); |
+ Trace new_trace(*current_trace); |
+ // If there are actions to be flushed we have to limit how many times |
+ // they are flushed. Take the budget of the parent trace and distribute |
+ // it fairly amongst the children. |
+ if (new_trace.actions() != NULL) { |
+ new_trace.set_flush_budget(new_flush_budget); |
+ } |
+ EmitOutOfLineContinuation(compiler, |
+ &new_trace, |
+ alternatives_->At(i), |
+ alt_gen, |
+ preload_characters, |
+ alt_gens.at(i + 1)->expects_preload); |
+ } |
+} |
+ |
+ |
+void ChoiceNode::EmitOutOfLineContinuation(RegExpCompiler* compiler, |
+ Trace* trace, |
+ GuardedAlternative alternative, |
+ AlternativeGeneration* alt_gen, |
+ intptr_t preload_characters, |
+ bool next_expects_preload) { |
+ if (!alt_gen->possible_success.IsLinked()) return; |
+ |
+ RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
+ macro_assembler->BindBlock(&alt_gen->possible_success); |
+ Trace out_of_line_trace(*trace); |
+ out_of_line_trace.set_characters_preloaded(preload_characters); |
+ out_of_line_trace.set_quick_check_performed(&alt_gen->quick_check_details); |
+ if (not_at_start_) out_of_line_trace.set_at_start(Trace::FALSE_VALUE); |
+ ZoneGrowableArray<Guard*>* guards = alternative.guards(); |
+ intptr_t guard_count = (guards == NULL) ? 0 : guards->length(); |
+ if (next_expects_preload) { |
+ BlockLabel reload_current_char; |
+ out_of_line_trace.set_backtrack(&reload_current_char); |
+ for (intptr_t j = 0; j < guard_count; j++) { |
+ GenerateGuard(macro_assembler, guards->At(j), &out_of_line_trace); |
+ } |
+ alternative.node()->Emit(compiler, &out_of_line_trace); |
+ macro_assembler->BindBlock(&reload_current_char); |
+ // Reload the current character, since the next quick check expects that. |
+ // We don't need to check bounds here because we only get into this |
+ // code through a quick check which already did the checked load. |
+ macro_assembler->LoadCurrentCharacter(trace->cp_offset(), |
+ NULL, |
+ false, |
+ preload_characters); |
+ macro_assembler->GoTo(&(alt_gen->after)); |
+ } else { |
+ out_of_line_trace.set_backtrack(&(alt_gen->after)); |
+ for (intptr_t j = 0; j < guard_count; j++) { |
+ GenerateGuard(macro_assembler, guards->At(j), &out_of_line_trace); |
+ } |
+ alternative.node()->Emit(compiler, &out_of_line_trace); |
+ } |
+} |
+ |
+ |
+void ActionNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ LimitResult limit_result = LimitVersions(compiler, trace); |
+ if (limit_result == DONE) return; |
+ ASSERT(limit_result == CONTINUE); |
+ |
+ RecursionCheck rc(compiler); |
+ |
+ switch (action_type_) { |
+ case STORE_POSITION: { |
+ Trace::DeferredCapture |
+ new_capture(data_.u_position_register.reg, |
+ data_.u_position_register.is_capture, |
+ trace); |
+ Trace new_trace = *trace; |
+ new_trace.add_action(&new_capture); |
+ on_success()->Emit(compiler, &new_trace); |
+ break; |
+ } |
+ case INCREMENT_REGISTER: { |
+ Trace::DeferredIncrementRegister |
+ new_increment(data_.u_increment_register.reg); |
+ Trace new_trace = *trace; |
+ new_trace.add_action(&new_increment); |
+ on_success()->Emit(compiler, &new_trace); |
+ break; |
+ } |
+ case SET_REGISTER: { |
+ Trace::DeferredSetRegister |
+ new_set(data_.u_store_register.reg, data_.u_store_register.value); |
+ Trace new_trace = *trace; |
+ new_trace.add_action(&new_set); |
+ on_success()->Emit(compiler, &new_trace); |
+ break; |
+ } |
+ case CLEAR_CAPTURES: { |
+ Trace::DeferredClearCaptures |
+ new_capture(Interval(data_.u_clear_captures.range_from, |
+ data_.u_clear_captures.range_to)); |
+ Trace new_trace = *trace; |
+ new_trace.add_action(&new_capture); |
+ on_success()->Emit(compiler, &new_trace); |
+ break; |
+ } |
+ case BEGIN_SUBMATCH: |
+ if (!trace->is_trivial()) { |
+ trace->Flush(compiler, this); |
+ } else { |
+ assembler->WriteCurrentPositionToRegister( |
+ data_.u_submatch.current_position_register, 0); |
+ assembler->WriteStackPointerToRegister( |
+ data_.u_submatch.stack_pointer_register); |
+ on_success()->Emit(compiler, trace); |
+ } |
+ break; |
+ case EMPTY_MATCH_CHECK: { |
+ intptr_t start_pos_reg = data_.u_empty_match_check.start_register; |
+ intptr_t stored_pos = 0; |
+ intptr_t rep_reg = data_.u_empty_match_check.repetition_register; |
+ bool has_minimum = (rep_reg != RegExpCompiler::kNoRegister); |
+ bool know_dist = trace->GetStoredPosition(start_pos_reg, &stored_pos); |
+ if (know_dist && !has_minimum && stored_pos == trace->cp_offset()) { |
+ // If we know we haven't advanced and there is no minimum we |
+ // can just backtrack immediately. |
+ assembler->GoTo(trace->backtrack()); |
+ } else if (know_dist && stored_pos < trace->cp_offset()) { |
+ // If we know we've advanced we can generate the continuation |
+ // immediately. |
+ on_success()->Emit(compiler, trace); |
+ } else if (!trace->is_trivial()) { |
+ trace->Flush(compiler, this); |
+ } else { |
+ BlockLabel skip_empty_check; |
+ // If we have a minimum number of repetitions we check the current |
+ // number first and skip the empty check if it's not enough. |
+ if (has_minimum) { |
+ intptr_t limit = data_.u_empty_match_check.repetition_limit; |
+ assembler->IfRegisterLT(rep_reg, limit, &skip_empty_check); |
+ } |
+ // If the match is empty we bail out, otherwise we fall through |
+ // to the on-success continuation. |
+ assembler->IfRegisterEqPos(data_.u_empty_match_check.start_register, |
+ trace->backtrack()); |
+ assembler->BindBlock(&skip_empty_check); |
+ on_success()->Emit(compiler, trace); |
+ } |
+ break; |
+ } |
+ case POSITIVE_SUBMATCH_SUCCESS: { |
+ if (!trace->is_trivial()) { |
+ trace->Flush(compiler, this); |
+ return; |
+ } |
+ assembler->ReadCurrentPositionFromRegister( |
+ data_.u_submatch.current_position_register); |
+ assembler->ReadStackPointerFromRegister( |
+ data_.u_submatch.stack_pointer_register); |
+ intptr_t clear_register_count = data_.u_submatch.clear_register_count; |
+ if (clear_register_count == 0) { |
+ on_success()->Emit(compiler, trace); |
+ return; |
+ } |
+ intptr_t clear_registers_from = data_.u_submatch.clear_register_from; |
+ BlockLabel clear_registers_backtrack; |
+ Trace new_trace = *trace; |
+ new_trace.set_backtrack(&clear_registers_backtrack); |
+ on_success()->Emit(compiler, &new_trace); |
+ |
+ assembler->BindBlock(&clear_registers_backtrack); |
+ intptr_t clear_registers_to = |
+ clear_registers_from + clear_register_count - 1; |
+ assembler->ClearRegisters(clear_registers_from, clear_registers_to); |
+ |
+ ASSERT(trace->backtrack() == NULL); |
+ assembler->Backtrack(); |
+ return; |
+ } |
+ default: |
+ UNREACHABLE(); |
+ } |
+} |
+ |
+ |
+void BackReferenceNode::Emit(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ if (!trace->is_trivial()) { |
+ trace->Flush(compiler, this); |
+ return; |
+ } |
+ |
+ LimitResult limit_result = LimitVersions(compiler, trace); |
+ if (limit_result == DONE) return; |
+ ASSERT(limit_result == CONTINUE); |
+ |
+ RecursionCheck rc(compiler); |
+ |
+ ASSERT(start_reg_ + 1 == end_reg_); |
+ if (compiler->ignore_case()) { |
+ assembler->CheckNotBackReferenceIgnoreCase(start_reg_, |
+ trace->backtrack()); |
+ } else { |
+ assembler->CheckNotBackReference(start_reg_, trace->backtrack()); |
+ } |
+ on_success()->Emit(compiler, trace); |
+} |
+ |
+ |
+void ActionNode::FillInBMInfo(intptr_t offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ if (action_type_ == BEGIN_SUBMATCH) { |
+ bm->SetRest(offset); |
+ } else if (action_type_ != POSITIVE_SUBMATCH_SUCCESS) { |
+ on_success()->FillInBMInfo(offset, budget - 1, bm, not_at_start); |
+ } |
+ SaveBMInfo(bm, not_at_start, offset); |
+} |
+ |
+ |
+void AssertionNode::FillInBMInfo(intptr_t offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ // Match the behaviour of EatsAtLeast on this node. |
+ if (assertion_type() == AT_START && not_at_start) return; |
+ on_success()->FillInBMInfo(offset, budget - 1, bm, not_at_start); |
+ SaveBMInfo(bm, not_at_start, offset); |
+} |
+ |
+ |
+void BackReferenceNode::FillInBMInfo(intptr_t offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ // Working out the set of characters that a backreference can match is too |
+ // hard, so we just say that any character can match. |
+ bm->SetRest(offset); |
+ SaveBMInfo(bm, not_at_start, offset); |
+} |
+ |
+ |
+// Returns the number of characters in the equivalence class, omitting those |
+// that cannot occur in the source string because it is ASCII. |
+static intptr_t GetCaseIndependentLetters(uint16_t character, |
+ bool ascii_subject, |
+ int32_t* letters) { |
+ unibrow::Mapping<unibrow::Ecma262UnCanonicalize> jsregexp_uncanonicalize; |
+ intptr_t length = jsregexp_uncanonicalize.get(character, '\0', letters); |
+ // Unibrow returns 0 or 1 for characters where case independence is |
+ // trivial. |
+ if (length == 0) { |
+ letters[0] = character; |
+ length = 1; |
+ } |
+ if (!ascii_subject || character <= Symbols::kMaxOneCharCodeSymbol) { |
+ return length; |
+ } |
+ // The standard requires that non-ASCII characters cannot have ASCII |
+ // character codes in their equivalence class. |
+ return 0; |
+} |
+ |
+ |
+void ChoiceNode::FillInBMInfo(intptr_t offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ ZoneGrowableArray<GuardedAlternative>* alts = alternatives(); |
+ budget = (budget - 1) / alts->length(); |
+ for (intptr_t i = 0; i < alts->length(); i++) { |
+ GuardedAlternative& alt = (*alts)[i]; |
+ if (alt.guards() != NULL && alt.guards()->length() != 0) { |
+ bm->SetRest(offset); // Give up trying to fill in info. |
+ SaveBMInfo(bm, not_at_start, offset); |
+ return; |
+ } |
+ alt.node()->FillInBMInfo(offset, budget, bm, not_at_start); |
+ } |
+ SaveBMInfo(bm, not_at_start, offset); |
+} |
+ |
+ |
+void EndNode::FillInBMInfo(intptr_t offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ // Returning 0 from EatsAtLeast should ensure we never get here. |
+ UNREACHABLE(); |
+} |
+ |
+ |
+void LoopChoiceNode::FillInBMInfo(intptr_t offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ if (body_can_be_zero_length_ || budget <= 0) { |
+ bm->SetRest(offset); |
+ SaveBMInfo(bm, not_at_start, offset); |
+ return; |
+ } |
+ ChoiceNode::FillInBMInfo(offset, budget - 1, bm, not_at_start); |
+ SaveBMInfo(bm, not_at_start, offset); |
+} |
+ |
+ |
+void TextNode::FillInBMInfo(intptr_t initial_offset, |
+ intptr_t budget, |
+ BoyerMooreLookahead* bm, |
+ bool not_at_start) { |
+ if (initial_offset >= bm->length()) return; |
+ intptr_t offset = initial_offset; |
+ intptr_t max_char = bm->max_char(); |
+ for (intptr_t i = 0; i < elements()->length(); i++) { |
+ if (offset >= bm->length()) { |
+ if (initial_offset == 0) set_bm_info(not_at_start, bm); |
+ return; |
+ } |
+ TextElement text = elements()->At(i); |
+ if (text.text_type() == TextElement::ATOM) { |
+ RegExpAtom* atom = text.atom(); |
+ for (intptr_t j = 0; j < atom->length(); j++, offset++) { |
+ if (offset >= bm->length()) { |
+ if (initial_offset == 0) set_bm_info(not_at_start, bm); |
+ return; |
+ } |
+ uint16_t character = atom->data()->At(j); |
+ if (bm->compiler()->ignore_case()) { |
+ int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
+ intptr_t length = GetCaseIndependentLetters( |
+ character, |
+ bm->max_char() == Symbols::kMaxOneCharCodeSymbol, |
+ chars); |
+ for (intptr_t j = 0; j < length; j++) { |
+ bm->Set(offset, chars[j]); |
+ } |
+ } else { |
+ if (character <= max_char) bm->Set(offset, character); |
+ } |
+ } |
+ } else { |
+ ASSERT(text.text_type() == TextElement::CHAR_CLASS); |
+ RegExpCharacterClass* char_class = text.char_class(); |
+ ZoneGrowableArray<CharacterRange>* ranges = char_class->ranges(); |
+ if (char_class->is_negated()) { |
+ bm->SetAll(offset); |
+ } else { |
+ for (intptr_t k = 0; k < ranges->length(); k++) { |
+ CharacterRange& range = (*ranges)[k]; |
+ if (range.from() > max_char) continue; |
+ intptr_t to = Utils::Minimum(max_char, |
+ static_cast<intptr_t>(range.to())); |
+ bm->SetInterval(offset, Interval(range.from(), to)); |
+ } |
+ } |
+ offset++; |
+ } |
+ } |
+ if (offset >= bm->length()) { |
+ if (initial_offset == 0) set_bm_info(not_at_start, bm); |
+ return; |
+ } |
+ on_success()->FillInBMInfo(offset, |
+ budget - 1, |
+ bm, |
+ true); // Not at start after a text node. |
+ if (initial_offset == 0) set_bm_info(not_at_start, bm); |
+} |
+ |
+ |
+// Check for [0-9A-Z_a-z]. |
+static void EmitWordCheck(RegExpMacroAssembler* assembler, |
+ BlockLabel* word, |
+ BlockLabel* non_word, |
+ bool fall_through_on_word) { |
+ if (assembler->CheckSpecialCharacterClass( |
+ fall_through_on_word ? 'w' : 'W', |
+ fall_through_on_word ? non_word : word)) { |
+ // Optimized implementation available. |
+ return; |
+ } |
+ assembler->CheckCharacterGT('z', non_word); |
+ assembler->CheckCharacterLT('0', non_word); |
+ assembler->CheckCharacterGT('a' - 1, word); |
+ assembler->CheckCharacterLT('9' + 1, word); |
+ assembler->CheckCharacterLT('A', non_word); |
+ assembler->CheckCharacterLT('Z' + 1, word); |
+ if (fall_through_on_word) { |
+ assembler->CheckNotCharacter('_', non_word); |
+ } else { |
+ assembler->CheckCharacter('_', word); |
+ } |
+} |
+ |
+ |
+// Emit the code to handle \b and \B (word-boundary or non-word-boundary). |
+void AssertionNode::EmitBoundaryCheck(RegExpCompiler* compiler, Trace* trace) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ Trace::TriBool next_is_word_character = Trace::UNKNOWN; |
+ bool not_at_start = (trace->at_start() == Trace::FALSE_VALUE); |
+ BoyerMooreLookahead* lookahead = bm_info(not_at_start); |
+ if (lookahead == NULL) { |
+ intptr_t eats_at_least = |
+ Utils::Minimum(kMaxLookaheadForBoyerMoore, |
+ EatsAtLeast(kMaxLookaheadForBoyerMoore, |
+ kRecursionBudget, |
+ not_at_start)); |
+ if (eats_at_least >= 1) { |
+ BoyerMooreLookahead* bm = |
+ new(I) BoyerMooreLookahead(eats_at_least, compiler, I); |
+ FillInBMInfo(0, kRecursionBudget, bm, not_at_start); |
+ if (bm->at(0)->is_non_word()) |
+ next_is_word_character = Trace::FALSE_VALUE; |
+ if (bm->at(0)->is_word()) next_is_word_character = Trace::TRUE_VALUE; |
+ } |
+ } else { |
+ if (lookahead->at(0)->is_non_word()) |
+ next_is_word_character = Trace::FALSE_VALUE; |
+ if (lookahead->at(0)->is_word()) |
+ next_is_word_character = Trace::TRUE_VALUE; |
+ } |
+ bool at_boundary = (assertion_type_ == AssertionNode::AT_BOUNDARY); |
+ if (next_is_word_character == Trace::UNKNOWN) { |
+ BlockLabel before_non_word; |
+ BlockLabel before_word; |
+ if (trace->characters_preloaded() != 1) { |
+ assembler->LoadCurrentCharacter(trace->cp_offset(), &before_non_word); |
+ } |
+ // Fall through on non-word. |
+ EmitWordCheck(assembler, &before_word, &before_non_word, false); |
+ // Next character is not a word character. |
+ assembler->BindBlock(&before_non_word); |
+ BlockLabel ok; |
+ // Backtrack on \B (non-boundary check) if previous is a word, |
+ // since we know next *is not* a word and this would be a boundary. |
+ BacktrackIfPrevious(compiler, trace, at_boundary ? kIsNonWord : kIsWord); |
+ |
+ if (!assembler->IsClosed()) { |
+ assembler->GoTo(&ok); |
+ } |
+ |
+ assembler->BindBlock(&before_word); |
+ BacktrackIfPrevious(compiler, trace, at_boundary ? kIsWord : kIsNonWord); |
+ assembler->BindBlock(&ok); |
+ } else if (next_is_word_character == Trace::TRUE_VALUE) { |
+ BacktrackIfPrevious(compiler, trace, at_boundary ? kIsWord : kIsNonWord); |
+ } else { |
+ ASSERT(next_is_word_character == Trace::FALSE_VALUE); |
+ BacktrackIfPrevious(compiler, trace, at_boundary ? kIsNonWord : kIsWord); |
+ } |
+} |
+ |
+ |
+void AssertionNode::BacktrackIfPrevious( |
+ RegExpCompiler* compiler, |
+ Trace* trace, |
+ AssertionNode::IfPrevious backtrack_if_previous) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ Trace new_trace(*trace); |
+ new_trace.InvalidateCurrentCharacter(); |
+ |
+ BlockLabel fall_through, dummy; |
+ |
+ BlockLabel* non_word = backtrack_if_previous == kIsNonWord ? |
+ new_trace.backtrack() : |
+ &fall_through; |
+ BlockLabel* word = backtrack_if_previous == kIsNonWord ? |
+ &fall_through : |
+ new_trace.backtrack(); |
+ |
+ if (new_trace.cp_offset() == 0) { |
+ // The start of input counts as a non-word character, so the question is |
+ // decided if we are at the start. |
+ assembler->CheckAtStart(non_word); |
+ } |
+ // We already checked that we are not at the start of input so it must be |
+ // OK to load the previous character. |
+ assembler->LoadCurrentCharacter(new_trace.cp_offset() - 1, &dummy, false); |
+ EmitWordCheck(assembler, word, non_word, backtrack_if_previous == kIsNonWord); |
+ |
+ assembler->BindBlock(&fall_through); |
+ on_success()->Emit(compiler, &new_trace); |
+} |
+ |
+ |
+static bool DeterminedAlready(QuickCheckDetails* quick_check, intptr_t offset) { |
+ if (quick_check == NULL) return false; |
+ if (offset >= quick_check->characters()) return false; |
+ return quick_check->positions(offset)->determines_perfectly; |
+} |
+ |
+ |
+static void UpdateBoundsCheck(intptr_t index, intptr_t* checked_up_to) { |
+ if (index > *checked_up_to) { |
+ *checked_up_to = index; |
+ } |
+} |
+ |
+ |
+typedef bool EmitCharacterFunction(Isolate* isolate, |
+ RegExpCompiler* compiler, |
+ uint16_t c, |
+ BlockLabel* on_failure, |
+ intptr_t cp_offset, |
+ bool check, |
+ bool preloaded); |
+ |
+ |
+static inline bool EmitSimpleCharacter(Isolate* isolate, |
+ RegExpCompiler* compiler, |
+ uint16_t c, |
+ BlockLabel* on_failure, |
+ intptr_t cp_offset, |
+ bool check, |
+ bool preloaded) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ bool bound_checked = false; |
+ if (!preloaded) { |
+ assembler->LoadCurrentCharacter( |
+ cp_offset, |
+ on_failure, |
+ check); |
+ bound_checked = true; |
+ } |
+ assembler->CheckNotCharacter(c, on_failure); |
+ return bound_checked; |
+} |
+ |
+ |
+static bool ShortCutEmitCharacterPair(RegExpMacroAssembler* macro_assembler, |
+ bool ascii, |
+ uint16_t c1, |
+ uint16_t c2, |
+ BlockLabel* on_failure) { |
+ uint16_t char_mask; |
+ if (ascii) { |
+ char_mask = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ char_mask = Utf16::kMaxCodeUnit; |
+ } |
+ uint16_t exor = c1 ^ c2; |
+ // Check whether exor has only one bit set. |
+ if (((exor - 1) & exor) == 0) { |
+ // If c1 and c2 differ only by one bit. |
+ // Ecma262UnCanonicalize always gives the highest number last. |
+ ASSERT(c2 > c1); |
+ uint16_t mask = char_mask ^ exor; |
+ macro_assembler->CheckNotCharacterAfterAnd(c1, mask, on_failure); |
+ return true; |
+ } |
+ ASSERT(c2 > c1); |
+ uint16_t diff = c2 - c1; |
+ if (((diff - 1) & diff) == 0 && c1 >= diff) { |
+ // If the characters differ by 2^n but don't differ by one bit then |
+ // subtract the difference from the found character, then do the or |
+ // trick. We avoid the theoretical case where negative numbers are |
+ // involved in order to simplify code generation. |
+ uint16_t mask = char_mask ^ diff; |
+ macro_assembler->CheckNotCharacterAfterMinusAnd(c1 - diff, |
+ diff, |
+ mask, |
+ on_failure); |
+ return true; |
+ } |
+ return false; |
+} |
+ |
+// Only emits letters (things that have case). Only used for case independent |
+// matches. |
+static inline bool EmitAtomLetter(Isolate* isolate, |
+ RegExpCompiler* compiler, |
+ uint16_t c, |
+ BlockLabel* on_failure, |
+ intptr_t cp_offset, |
+ bool check, |
+ bool preloaded) { |
+ RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
+ bool ascii = compiler->ascii(); |
+ int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
+ intptr_t length = GetCaseIndependentLetters(c, ascii, chars); |
+ if (length <= 1) return false; |
+ // We may not need to check against the end of the input string |
+ // if this character lies before a character that matched. |
+ if (!preloaded) { |
+ macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check); |
+ } |
+ BlockLabel ok; |
+ ASSERT(unibrow::Ecma262UnCanonicalize::kMaxWidth == 4); |
+ switch (length) { |
+ case 2: { |
+ if (ShortCutEmitCharacterPair(macro_assembler, |
+ ascii, |
+ chars[0], |
+ chars[1], |
+ on_failure)) { |
+ } else { |
+ macro_assembler->CheckCharacter(chars[0], &ok); |
+ macro_assembler->CheckNotCharacter(chars[1], on_failure); |
+ macro_assembler->BindBlock(&ok); |
+ } |
+ break; |
+ } |
+ case 4: |
+ macro_assembler->CheckCharacter(chars[3], &ok); |
+ // Fall through! |
+ case 3: |
+ macro_assembler->CheckCharacter(chars[0], &ok); |
+ macro_assembler->CheckCharacter(chars[1], &ok); |
+ macro_assembler->CheckNotCharacter(chars[2], on_failure); |
+ macro_assembler->BindBlock(&ok); |
+ break; |
+ default: |
+ UNREACHABLE(); |
+ break; |
+ } |
+ return true; |
+} |
+ |
+ |
+// Only emits non-letters (things that don't have case). Only used for case |
+// independent matches. |
+static inline bool EmitAtomNonLetter(Isolate* isolate, |
+ RegExpCompiler* compiler, |
+ uint16_t c, |
+ BlockLabel* on_failure, |
+ intptr_t cp_offset, |
+ bool check, |
+ bool preloaded) { |
+ RegExpMacroAssembler* macro_assembler = compiler->macro_assembler(); |
+ bool ascii = compiler->ascii(); |
+ int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
+ intptr_t length = GetCaseIndependentLetters(c, ascii, chars); |
+ if (length < 1) { |
+ // This can't match. Must be an ASCII subject and a non-ASCII character. |
+ // We do not need to do anything since the ASCII pass already handled this. |
+ return false; // Bounds not checked. |
+ } |
+ bool checked = false; |
+ // We handle the length > 1 case in a later pass. |
+ if (length == 1) { |
+ if (ascii && c > Symbols::kMaxOneCharCodeSymbol) { |
+ // Can't match - see above. |
+ return false; // Bounds not checked. |
+ } |
+ if (!preloaded) { |
+ macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check); |
+ checked = check; |
+ } |
+ macro_assembler->CheckNotCharacter(c, on_failure); |
+ } |
+ return checked; |
+} |
+ |
+ |
+static void EmitBoundaryTest(RegExpMacroAssembler* masm, |
+ intptr_t border, |
+ BlockLabel* fall_through, |
+ BlockLabel* above_or_equal, |
+ BlockLabel* below) { |
+ if (below != fall_through) { |
+ masm->CheckCharacterLT(border, below); |
+ if (above_or_equal != fall_through) masm->GoTo(above_or_equal); |
+ } else { |
+ masm->CheckCharacterGT(border - 1, above_or_equal); |
+ } |
+} |
+ |
+ |
+static void EmitDoubleBoundaryTest(RegExpMacroAssembler* masm, |
+ intptr_t first, |
+ intptr_t last, |
+ BlockLabel* fall_through, |
+ BlockLabel* in_range, |
+ BlockLabel* out_of_range) { |
+ if (in_range == fall_through) { |
+ if (first == last) { |
+ masm->CheckNotCharacter(first, out_of_range); |
+ } else { |
+ masm->CheckCharacterNotInRange(first, last, out_of_range); |
+ } |
+ } else { |
+ if (first == last) { |
+ masm->CheckCharacter(first, in_range); |
+ } else { |
+ masm->CheckCharacterInRange(first, last, in_range); |
+ } |
+ if (out_of_range != fall_through) masm->GoTo(out_of_range); |
+ } |
+} |
+ |
+ |
+static void CutOutRange(RegExpMacroAssembler* masm, |
+ ZoneGrowableArray<int>* ranges, |
+ intptr_t start_index, |
+ intptr_t end_index, |
+ intptr_t cut_index, |
+ BlockLabel* even_label, |
+ BlockLabel* odd_label) { |
+ bool odd = (((cut_index - start_index) & 1) == 1); |
+ BlockLabel* in_range_label = odd ? odd_label : even_label; |
+ BlockLabel dummy; |
+ EmitDoubleBoundaryTest(masm, |
+ ranges->At(cut_index), |
+ ranges->At(cut_index + 1) - 1, |
+ &dummy, |
+ in_range_label, |
+ &dummy); |
+ ASSERT(!dummy.IsLinked()); |
+ // Cut out the single range by rewriting the array. This creates a new |
+ // range that is a merger of the two ranges on either side of the one we |
+ // are cutting out. The oddity of the labels is preserved. |
+ for (intptr_t j = cut_index; j > start_index; j--) { |
+ (*ranges)[j] = ranges->At(j - 1); |
+ } |
+ for (intptr_t j = cut_index + 1; j < end_index; j++) { |
+ (*ranges)[j] = ranges->At(j + 1); |
+ } |
+} |
+ |
+ |
+// even_label is for ranges[i] to ranges[i + 1] where i - start_index is even. |
+// odd_label is for ranges[i] to ranges[i + 1] where i - start_index is odd. |
+static void EmitUseLookupTable( |
+ RegExpMacroAssembler* masm, |
+ ZoneGrowableArray<int>* ranges, |
+ intptr_t start_index, |
+ intptr_t end_index, |
+ intptr_t min_char, |
+ BlockLabel* fall_through, |
+ BlockLabel* even_label, |
+ BlockLabel* odd_label) { |
+ static const intptr_t kSize = RegExpMacroAssembler::kTableSize; |
+ static const intptr_t kMask = RegExpMacroAssembler::kTableMask; |
+ |
+ intptr_t base = (min_char & ~kMask); |
+ |
+ // Assert that everything is on one kTableSize page. |
+ for (intptr_t i = start_index; i <= end_index; i++) { |
+ ASSERT((ranges->At(i) & ~kMask) == base); |
+ } |
+ ASSERT(start_index == 0 || (ranges->At(start_index - 1) & ~kMask) <= base); |
+ |
+ char templ[kSize]; |
+ BlockLabel* on_bit_set; |
+ BlockLabel* on_bit_clear; |
+ intptr_t bit; |
+ if (even_label == fall_through) { |
+ on_bit_set = odd_label; |
+ on_bit_clear = even_label; |
+ bit = 1; |
+ } else { |
+ on_bit_set = even_label; |
+ on_bit_clear = odd_label; |
+ bit = 0; |
+ } |
+ for (intptr_t i = 0; i < (ranges->At(start_index) & kMask) && i < kSize; |
+ i++) { |
+ templ[i] = bit; |
+ } |
+ intptr_t j = 0; |
+ bit ^= 1; |
+ for (intptr_t i = start_index; i < end_index; i++) { |
+ for (j = (ranges->At(i) & kMask); j < (ranges->At(i + 1) & kMask); j++) { |
+ templ[j] = bit; |
+ } |
+ bit ^= 1; |
+ } |
+ for (intptr_t i = j; i < kSize; i++) { |
+ templ[i] = bit; |
+ } |
+ // TODO(erikcorry): Cache these. |
+ const TypedData& ba = TypedData::ZoneHandle( |
+ masm->isolate(), |
+ TypedData::New(kTypedDataUint8ArrayCid, kSize, Heap::kOld)); |
+ for (intptr_t i = 0; i < kSize; i++) { |
+ ba.SetUint8(i, templ[i]); |
+ } |
+ masm->CheckBitInTable(ba, on_bit_set); |
+ if (on_bit_clear != fall_through) masm->GoTo(on_bit_clear); |
+} |
+ |
+ |
+// Unicode case. Split the search space into kSize spaces that are handled |
+// with recursion. |
+static void SplitSearchSpace(ZoneGrowableArray<int>* ranges, |
+ intptr_t start_index, |
+ intptr_t end_index, |
+ intptr_t* new_start_index, |
+ intptr_t* new_end_index, |
+ intptr_t* border) { |
+ static const intptr_t kSize = RegExpMacroAssembler::kTableSize; |
+ static const intptr_t kMask = RegExpMacroAssembler::kTableMask; |
+ |
+ intptr_t first = ranges->At(start_index); |
+ intptr_t last = ranges->At(end_index) - 1; |
+ |
+ *new_start_index = start_index; |
+ *border = (ranges->At(start_index) & ~kMask) + kSize; |
+ while (*new_start_index < end_index) { |
+ if (ranges->At(*new_start_index) > *border) break; |
+ (*new_start_index)++; |
+ } |
+ // new_start_index is the index of the first edge that is beyond the |
+ // current kSize space. |
+ |
+ // For very large search spaces we do a binary chop search of the non-ASCII |
+ // space instead of just going to the end of the current kSize space. The |
+ // heuristics are complicated a little by the fact that any 128-character |
+ // encoding space can be quickly tested with a table lookup, so we don't |
+ // wish to do binary chop search at a smaller granularity than that. A |
+ // 128-character space can take up a lot of space in the ranges array if, |
+ // for example, we only want to match every second character (eg. the lower |
+ // case characters on some Unicode pages). |
+ intptr_t binary_chop_index = (end_index + start_index) / 2; |
+ // The first test ensures that we get to the code that handles the ASCII |
+ // range with a single not-taken branch, speeding up this important |
+ // character range (even non-ASCII charset-based text has spaces and |
+ // punctuation). |
+ if (*border - 1 > Symbols::kMaxOneCharCodeSymbol && // ASCII case. |
+ end_index - start_index > (*new_start_index - start_index) * 2 && |
+ last - first > kSize * 2 && |
+ binary_chop_index > *new_start_index && |
+ ranges->At(binary_chop_index) >= first + 2 * kSize) { |
+ intptr_t scan_forward_for_section_border = binary_chop_index;; |
+ intptr_t new_border = (ranges->At(binary_chop_index) | kMask) + 1; |
+ |
+ while (scan_forward_for_section_border < end_index) { |
+ if (ranges->At(scan_forward_for_section_border) > new_border) { |
+ *new_start_index = scan_forward_for_section_border; |
+ *border = new_border; |
+ break; |
+ } |
+ scan_forward_for_section_border++; |
+ } |
+ } |
+ |
+ ASSERT(*new_start_index > start_index); |
+ *new_end_index = *new_start_index - 1; |
+ if (ranges->At(*new_end_index) == *border) { |
+ (*new_end_index)--; |
+ } |
+ if (*border >= ranges->At(end_index)) { |
+ *border = ranges->At(end_index); |
+ *new_start_index = end_index; // Won't be used. |
+ *new_end_index = end_index - 1; |
+ } |
+} |
+ |
+ |
+// Gets a series of segment boundaries representing a character class. If the |
+// character is in the range between an even and an odd boundary (counting from |
+// start_index) then go to even_label, otherwise go to odd_label. We already |
+// know that the character is in the range of min_char to max_char inclusive. |
+// Either label can be NULL indicating backtracking. Either label can also be |
+// equal to the fall_through label. |
+static void GenerateBranches(RegExpMacroAssembler* masm, |
+ ZoneGrowableArray<int>* ranges, |
+ intptr_t start_index, |
+ intptr_t end_index, |
+ uint16_t min_char, |
+ uint16_t max_char, |
+ BlockLabel* fall_through, |
+ BlockLabel* even_label, |
+ BlockLabel* odd_label) { |
+ intptr_t first = ranges->At(start_index); |
+ intptr_t last = ranges->At(end_index) - 1; |
+ |
+ ASSERT(min_char < first); |
+ |
+ // Just need to test if the character is before or on-or-after |
+ // a particular character. |
+ if (start_index == end_index) { |
+ EmitBoundaryTest(masm, first, fall_through, even_label, odd_label); |
+ return; |
+ } |
+ |
+ // Another almost trivial case: There is one interval in the middle that is |
+ // different from the end intervals. |
+ if (start_index + 1 == end_index) { |
+ EmitDoubleBoundaryTest( |
+ masm, first, last, fall_through, even_label, odd_label); |
+ return; |
+ } |
+ |
+ // It's not worth using table lookup if there are very few intervals in the |
+ // character class. |
+ if (end_index - start_index <= 6) { |
+ // It is faster to test for individual characters, so we look for those |
+ // first, then try arbitrary ranges in the second round. |
+ static intptr_t kNoCutIndex = -1; |
+ intptr_t cut = kNoCutIndex; |
+ for (intptr_t i = start_index; i < end_index; i++) { |
+ if (ranges->At(i) == ranges->At(i + 1) - 1) { |
+ cut = i; |
+ break; |
+ } |
+ } |
+ if (cut == kNoCutIndex) cut = start_index; |
+ CutOutRange( |
+ masm, ranges, start_index, end_index, cut, even_label, odd_label); |
+ ASSERT(end_index - start_index >= 2); |
+ GenerateBranches(masm, |
+ ranges, |
+ start_index + 1, |
+ end_index - 1, |
+ min_char, |
+ max_char, |
+ fall_through, |
+ even_label, |
+ odd_label); |
+ return; |
+ } |
+ |
+ // If there are a lot of intervals in the regexp, then we will use tables to |
+ // determine whether the character is inside or outside the character class. |
+ static const intptr_t kBits = RegExpMacroAssembler::kTableSizeBits; |
+ |
+ if ((max_char >> kBits) == (min_char >> kBits)) { |
+ EmitUseLookupTable(masm, |
+ ranges, |
+ start_index, |
+ end_index, |
+ min_char, |
+ fall_through, |
+ even_label, |
+ odd_label); |
+ return; |
+ } |
+ |
+ if ((min_char >> kBits) != (first >> kBits)) { |
+ masm->CheckCharacterLT(first, odd_label); |
+ GenerateBranches(masm, |
+ ranges, |
+ start_index + 1, |
+ end_index, |
+ first, |
+ max_char, |
+ fall_through, |
+ odd_label, |
+ even_label); |
+ return; |
+ } |
+ |
+ intptr_t new_start_index = 0; |
+ intptr_t new_end_index = 0; |
+ intptr_t border = 0; |
+ |
+ SplitSearchSpace(ranges, |
+ start_index, |
+ end_index, |
+ &new_start_index, |
+ &new_end_index, |
+ &border); |
+ |
+ BlockLabel handle_rest; |
+ BlockLabel* above = &handle_rest; |
+ if (border == last + 1) { |
+ // We didn't find any section that started after the limit, so everything |
+ // above the border is one of the terminal labels. |
+ above = (end_index & 1) != (start_index & 1) ? odd_label : even_label; |
+ ASSERT(new_end_index == end_index - 1); |
+ } |
+ |
+ ASSERT(start_index <= new_end_index); |
+ ASSERT(new_start_index <= end_index); |
+ ASSERT(start_index < new_start_index); |
+ ASSERT(new_end_index < end_index); |
+ ASSERT(new_end_index + 1 == new_start_index || |
+ (new_end_index + 2 == new_start_index && |
+ border == ranges->At(new_end_index + 1))); |
+ ASSERT(min_char < border - 1); |
+ ASSERT(border < max_char); |
+ ASSERT(ranges->At(new_end_index) < border); |
+ ASSERT(border < ranges->At(new_start_index) || |
+ (border == ranges->At(new_start_index) && |
+ new_start_index == end_index && |
+ new_end_index == end_index - 1 && |
+ border == last + 1)); |
+ ASSERT(new_start_index == 0 || border >= ranges->At(new_start_index - 1)); |
+ |
+ masm->CheckCharacterGT(border - 1, above); |
+ BlockLabel dummy; |
+ GenerateBranches(masm, |
+ ranges, |
+ start_index, |
+ new_end_index, |
+ min_char, |
+ border - 1, |
+ &dummy, |
+ even_label, |
+ odd_label); |
+ |
+ if (handle_rest.IsLinked()) { |
+ masm->BindBlock(&handle_rest); |
+ bool flip = (new_start_index & 1) != (start_index & 1); |
+ GenerateBranches(masm, |
+ ranges, |
+ new_start_index, |
+ end_index, |
+ border, |
+ max_char, |
+ &dummy, |
+ flip ? odd_label : even_label, |
+ flip ? even_label : odd_label); |
+ } |
+} |
+ |
+ |
+static void EmitCharClass(RegExpMacroAssembler* macro_assembler, |
+ RegExpCharacterClass* cc, |
+ bool ascii, |
+ BlockLabel* on_failure, |
+ intptr_t cp_offset, |
+ bool check_offset, |
+ bool preloaded, |
+ Isolate* isolate) { |
+ ZoneGrowableArray<CharacterRange>* ranges = cc->ranges(); |
+ if (!CharacterRange::IsCanonical(ranges)) { |
+ CharacterRange::Canonicalize(ranges); |
+ } |
+ |
+ intptr_t max_char; |
+ if (ascii) { |
+ max_char = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ max_char = Utf16::kMaxCodeUnit; |
+ } |
+ |
+ intptr_t range_count = ranges->length(); |
+ |
+ intptr_t last_valid_range = range_count - 1; |
+ while (last_valid_range >= 0) { |
+ CharacterRange& range = (*ranges)[last_valid_range]; |
+ if (range.from() <= max_char) { |
+ break; |
+ } |
+ last_valid_range--; |
+ } |
+ |
+ if (last_valid_range < 0) { |
+ if (!cc->is_negated()) { |
+ macro_assembler->GoTo(on_failure); |
+ } |
+ if (check_offset) { |
+ macro_assembler->CheckPosition(cp_offset, on_failure); |
+ } |
+ return; |
+ } |
+ |
+ if (last_valid_range == 0 && |
+ ranges->At(0).IsEverything(max_char)) { |
+ if (cc->is_negated()) { |
+ macro_assembler->GoTo(on_failure); |
+ } else { |
+ // This is a common case hit by non-anchored expressions. |
+ if (check_offset) { |
+ macro_assembler->CheckPosition(cp_offset, on_failure); |
+ } |
+ } |
+ return; |
+ } |
+ if (last_valid_range == 0 && |
+ !cc->is_negated() && |
+ ranges->At(0).IsEverything(max_char)) { |
+ // This is a common case hit by non-anchored expressions. |
+ if (check_offset) { |
+ macro_assembler->CheckPosition(cp_offset, on_failure); |
+ } |
+ return; |
+ } |
+ |
+ if (!preloaded) { |
+ macro_assembler->LoadCurrentCharacter(cp_offset, on_failure, check_offset); |
+ } |
+ |
+ if (cc->is_standard() && |
+ macro_assembler->CheckSpecialCharacterClass(cc->standard_type(), |
+ on_failure)) { |
+ return; |
+ } |
+ |
+ |
+ // A new list with ascending entries. Each entry is a code unit |
+ // where there is a boundary between code units that are part of |
+ // the class and code units that are not. Normally we insert an |
+ // entry at zero which goes to the failure label, but if there |
+ // was already one there we fall through for success on that entry. |
+ // Subsequent entries have alternating meaning (success/failure). |
+ ZoneGrowableArray<int>* range_boundaries = |
+ new(isolate) ZoneGrowableArray<int>(last_valid_range); |
+ |
+ bool zeroth_entry_is_failure = !cc->is_negated(); |
+ |
+ for (intptr_t i = 0; i <= last_valid_range; i++) { |
+ CharacterRange& range = (*ranges)[i]; |
+ if (range.from() == 0) { |
+ ASSERT(i == 0); |
+ zeroth_entry_is_failure = !zeroth_entry_is_failure; |
+ } else { |
+ range_boundaries->Add(range.from()); |
+ } |
+ range_boundaries->Add(range.to() + 1); |
+ } |
+ intptr_t end_index = range_boundaries->length() - 1; |
+ if (range_boundaries->At(end_index) > max_char) { |
+ end_index--; |
+ } |
+ |
+ BlockLabel fall_through; |
+ GenerateBranches(macro_assembler, |
+ range_boundaries, |
+ 0, // start_index. |
+ end_index, |
+ 0, // min_char. |
+ max_char, |
+ &fall_through, |
+ zeroth_entry_is_failure ? &fall_through : on_failure, |
+ zeroth_entry_is_failure ? on_failure : &fall_through); |
+ macro_assembler->BindBlock(&fall_through); |
+} |
+ |
+ |
+// We call this repeatedly to generate code for each pass over the text node. |
+// The passes are in increasing order of difficulty because we hope one |
+// of the first passes will fail in which case we are saved the work of the |
+// later passes. for example for the case independent regexp /%[asdfghjkl]a/ |
+// we will check the '%' in the first pass, the case independent 'a' in the |
+// second pass and the character class in the last pass. |
+// |
+// The passes are done from right to left, so for example to test for /bar/ |
+// we will first test for an 'r' with offset 2, then an 'a' with offset 1 |
+// and then a 'b' with offset 0. This means we can avoid the end-of-input |
+// bounds check most of the time. In the example we only need to check for |
+// end-of-input when loading the putative 'r'. |
+// |
+// A slight complication involves the fact that the first character may already |
+// be fetched into a register by the previous node. In this case we want to |
+// do the test for that character first. We do this in separate passes. The |
+// 'preloaded' argument indicates that we are doing such a 'pass'. If such a |
+// pass has been performed then subsequent passes will have true in |
+// first_element_checked to indicate that that character does not need to be |
+// checked again. |
+// |
+// In addition to all this we are passed a Trace, which can |
+// contain an AlternativeGeneration object. In this AlternativeGeneration |
+// object we can see details of any quick check that was already passed in |
+// order to get to the code we are now generating. The quick check can involve |
+// loading characters, which means we do not need to recheck the bounds |
+// up to the limit the quick check already checked. In addition the quick |
+// check can have involved a mask and compare operation which may simplify |
+// or obviate the need for further checks at some character positions. |
+void TextNode::TextEmitPass(RegExpCompiler* compiler, |
+ TextEmitPassType pass, |
+ bool preloaded, |
+ Trace* trace, |
+ bool first_element_checked, |
+ intptr_t* checked_up_to) { |
+ RegExpMacroAssembler* assembler = compiler->macro_assembler(); |
+ bool ascii = compiler->ascii(); |
+ BlockLabel* backtrack = trace->backtrack(); |
+ QuickCheckDetails* quick_check = trace->quick_check_performed(); |
+ intptr_t element_count = elms_->length(); |
+ for (intptr_t i = preloaded ? 0 : element_count - 1; i >= 0; i--) { |
+ TextElement elm = elms_->At(i); |
+ intptr_t cp_offset = trace->cp_offset() + elm.cp_offset(); |
+ if (elm.text_type() == TextElement::ATOM) { |
+ ZoneGrowableArray<uint16_t>* quarks = elm.atom()->data(); |
+ for (intptr_t j = preloaded ? 0 : quarks->length() - 1; j >= 0; j--) { |
+ if (first_element_checked && i == 0 && j == 0) continue; |
+ if (DeterminedAlready(quick_check, elm.cp_offset() + j)) continue; |
+ EmitCharacterFunction* emit_function = NULL; |
+ switch (pass) { |
+ case NON_ASCII_MATCH: |
+ ASSERT(ascii); |
+ if (quarks->At(j) > Symbols::kMaxOneCharCodeSymbol) { |
+ assembler->GoTo(backtrack); |
+ return; |
+ } |
+ break; |
+ case NON_LETTER_CHARACTER_MATCH: |
+ emit_function = &EmitAtomNonLetter; |
+ break; |
+ case SIMPLE_CHARACTER_MATCH: |
+ emit_function = &EmitSimpleCharacter; |
+ break; |
+ case CASE_CHARACTER_MATCH: |
+ emit_function = &EmitAtomLetter; |
+ break; |
+ default: |
+ break; |
+ } |
+ if (emit_function != NULL) { |
+ bool bound_checked = emit_function(I, |
+ compiler, |
+ quarks->At(j), |
+ backtrack, |
+ cp_offset + j, |
+ *checked_up_to < cp_offset + j, |
+ preloaded); |
+ if (bound_checked) UpdateBoundsCheck(cp_offset + j, checked_up_to); |
+ } |
+ } |
+ } else { |
+ ASSERT(elm.text_type() == TextElement::CHAR_CLASS); |
+ if (pass == CHARACTER_CLASS_MATCH) { |
+ if (first_element_checked && i == 0) continue; |
+ if (DeterminedAlready(quick_check, elm.cp_offset())) continue; |
+ RegExpCharacterClass* cc = elm.char_class(); |
+ EmitCharClass(assembler, |
+ cc, |
+ ascii, |
+ backtrack, |
+ cp_offset, |
+ *checked_up_to < cp_offset, |
+ preloaded, |
+ I); |
+ UpdateBoundsCheck(cp_offset, checked_up_to); |
+ } |
+ } |
+ } |
+} |
+ |
+ |
+intptr_t ChoiceNode::CalculatePreloadCharacters(RegExpCompiler* compiler, |
+ intptr_t eats_at_least) { |
+ intptr_t preload_characters = Utils::Minimum(static_cast<intptr_t>(4), |
+ eats_at_least); |
+ if (compiler->macro_assembler()->CanReadUnaligned()) { |
+ bool ascii = compiler->ascii(); |
+ if (ascii) { |
+ if (preload_characters > 4) preload_characters = 4; |
+ // We can't preload 3 characters because there is no machine instruction |
+ // to do that. We can't just load 4 because we could be reading |
+ // beyond the end of the string, which could cause a memory fault. |
+ if (preload_characters == 3) preload_characters = 2; |
+ } else { |
+ if (preload_characters > 2) preload_characters = 2; |
+ } |
+ } else { |
+ if (preload_characters > 1) preload_characters = 1; |
+ } |
+ return preload_characters; |
+} |
+ |
+ |
+intptr_t TextNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ intptr_t answer = Length(); |
+ if (answer >= still_to_find) return answer; |
+ if (budget <= 0) return answer; |
+ // We are not at start after this node so we set the last argument to 'true'. |
+ return answer + on_success()->EatsAtLeast(still_to_find - answer, |
+ budget - 1, |
+ true); |
+} |
+ |
+ |
+intptr_t ActionNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ if (budget <= 0) return 0; |
+ if (action_type_ == POSITIVE_SUBMATCH_SUCCESS) return 0; // Rewinds input! |
+ return on_success()->EatsAtLeast(still_to_find, |
+ budget - 1, |
+ not_at_start); |
+} |
+ |
+ |
+intptr_t AssertionNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ if (budget <= 0) return 0; |
+ // If we know we are not at the start and we are asked "how many characters |
+ // will you match if you succeed?" then we can answer anything since false |
+ // implies false. So lets just return the max answer (still_to_find) since |
+ // that won't prevent us from preloading a lot of characters for the other |
+ // branches in the node graph. |
+ if (assertion_type() == AT_START && not_at_start) return still_to_find; |
+ return on_success()->EatsAtLeast(still_to_find, |
+ budget - 1, |
+ not_at_start); |
+} |
+ |
+ |
+intptr_t BackReferenceNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ if (budget <= 0) return 0; |
+ return on_success()->EatsAtLeast(still_to_find, |
+ budget - 1, |
+ not_at_start); |
+} |
+ |
+ |
+intptr_t ChoiceNode::EatsAtLeastHelper(intptr_t still_to_find, |
+ intptr_t budget, |
+ RegExpNode* ignore_this_node, |
+ bool not_at_start) { |
+ if (budget <= 0) return 0; |
+ intptr_t min = 100; |
+ intptr_t choice_count = alternatives_->length(); |
+ budget = (budget - 1) / choice_count; |
+ for (intptr_t i = 0; i < choice_count; i++) { |
+ RegExpNode* node = (*alternatives_)[i].node(); |
+ if (node == ignore_this_node) continue; |
+ intptr_t node_eats_at_least = |
+ node->EatsAtLeast(still_to_find, budget, not_at_start); |
+ if (node_eats_at_least < min) min = node_eats_at_least; |
+ if (min == 0) return 0; |
+ } |
+ return min; |
+} |
+ |
+ |
+intptr_t ChoiceNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ return EatsAtLeastHelper(still_to_find, |
+ budget, |
+ NULL, |
+ not_at_start); |
+} |
+ |
+ |
+intptr_t NegativeLookaheadChoiceNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ if (budget <= 0) return 0; |
+ // Alternative 0 is the negative lookahead, alternative 1 is what comes |
+ // afterwards. |
+ RegExpNode* node = (*alternatives_)[1].node(); |
+ return node->EatsAtLeast(still_to_find, budget - 1, not_at_start); |
+} |
+ |
+ |
+// Takes the left-most 1-bit and smears it out, setting all bits to its right. |
+static inline uint32_t SmearBitsRight(uint32_t v) { |
+ v |= v >> 1; |
+ v |= v >> 2; |
+ v |= v >> 4; |
+ v |= v >> 8; |
+ v |= v >> 16; |
+ return v; |
+} |
+ |
+ |
+// Here is the meat of GetQuickCheckDetails (see also the comment on the |
+// super-class in the .h file). |
+// |
+// We iterate along the text object, building up for each character a |
+// mask and value that can be used to test for a quick failure to match. |
+// The masks and values for the positions will be combined into a single |
+// machine word for the current character width in order to be used in |
+// generating a quick check. |
+void TextNode::GetQuickCheckDetails(QuickCheckDetails* details, |
+ RegExpCompiler* compiler, |
+ intptr_t characters_filled_in, |
+ bool not_at_start) { |
+ ASSERT(characters_filled_in < details->characters()); |
+ intptr_t characters = details->characters(); |
+ intptr_t char_mask; |
+ if (compiler->ascii()) { |
+ char_mask = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ char_mask = Utf16::kMaxCodeUnit; |
+ } |
+ for (intptr_t k = 0; k < elms_->length(); k++) { |
+ TextElement elm = elms_->At(k); |
+ if (elm.text_type() == TextElement::ATOM) { |
+ ZoneGrowableArray<uint16_t>* quarks = elm.atom()->data(); |
+ for (intptr_t i = 0; i < characters && i < quarks->length(); i++) { |
+ QuickCheckDetails::Position* pos = |
+ details->positions(characters_filled_in); |
+ uint16_t c = quarks->At(i); |
+ if (c > char_mask) { |
+ // If we expect a non-ASCII character from an ASCII string, |
+ // there is no way we can match. Not even case independent |
+ // matching can turn an ASCII character into non-ASCII or |
+ // vice versa. |
+ details->set_cannot_match(); |
+ pos->determines_perfectly = false; |
+ return; |
+ } |
+ if (compiler->ignore_case()) { |
+ int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
+ intptr_t length = |
+ GetCaseIndependentLetters(c, compiler->ascii(), chars); |
+ ASSERT(length != 0); // Can only happen if c > char_mask (see above). |
+ if (length == 1) { |
+ // This letter has no case equivalents, so it's nice and simple |
+ // and the mask-compare will determine definitely whether we have |
+ // a match at this character position. |
+ pos->mask = char_mask; |
+ pos->value = c; |
+ pos->determines_perfectly = true; |
+ } else { |
+ uint32_t common_bits = char_mask; |
+ uint32_t bits = chars[0]; |
+ for (intptr_t j = 1; j < length; j++) { |
+ uint32_t differing_bits = ((chars[j] & common_bits) ^ bits); |
+ common_bits ^= differing_bits; |
+ bits &= common_bits; |
+ } |
+ // If length is 2 and common bits has only one zero in it then |
+ // our mask and compare instruction will determine definitely |
+ // whether we have a match at this character position. Otherwise |
+ // it can only be an approximate check. |
+ uint32_t one_zero = (common_bits | ~char_mask); |
+ if (length == 2 && ((~one_zero) & ((~one_zero) - 1)) == 0) { |
+ pos->determines_perfectly = true; |
+ } |
+ pos->mask = common_bits; |
+ pos->value = bits; |
+ } |
+ } else { |
+ // Don't ignore case. Nice simple case where the mask-compare will |
+ // determine definitely whether we have a match at this character |
+ // position. |
+ pos->mask = char_mask; |
+ pos->value = c; |
+ pos->determines_perfectly = true; |
+ } |
+ characters_filled_in++; |
+ ASSERT(characters_filled_in <= details->characters()); |
+ if (characters_filled_in == details->characters()) { |
+ return; |
+ } |
+ } |
+ } else { |
+ QuickCheckDetails::Position* pos = |
+ details->positions(characters_filled_in); |
+ RegExpCharacterClass* tree = elm.char_class(); |
+ ZoneGrowableArray<CharacterRange>* ranges = tree->ranges(); |
+ if (tree->is_negated()) { |
+ // A quick check uses multi-character mask and compare. There is no |
+ // useful way to incorporate a negative char class into this scheme |
+ // so we just conservatively create a mask and value that will always |
+ // succeed. |
+ pos->mask = 0; |
+ pos->value = 0; |
+ } else { |
+ intptr_t first_range = 0; |
+ while (ranges->At(first_range).from() > char_mask) { |
+ first_range++; |
+ if (first_range == ranges->length()) { |
+ details->set_cannot_match(); |
+ pos->determines_perfectly = false; |
+ return; |
+ } |
+ } |
+ CharacterRange range = ranges->At(first_range); |
+ uint16_t from = range.from(); |
+ uint16_t to = range.to(); |
+ if (to > char_mask) { |
+ to = char_mask; |
+ } |
+ uint32_t differing_bits = (from ^ to); |
+ // A mask and compare is only perfect if the differing bits form a |
+ // number like 00011111 with one single block of trailing 1s. |
+ if ((differing_bits & (differing_bits + 1)) == 0 && |
+ from + differing_bits == to) { |
+ pos->determines_perfectly = true; |
+ } |
+ uint32_t common_bits = ~SmearBitsRight(differing_bits); |
+ uint32_t bits = (from & common_bits); |
+ for (intptr_t i = first_range + 1; i < ranges->length(); i++) { |
+ CharacterRange range = ranges->At(i); |
+ uint16_t from = range.from(); |
+ uint16_t to = range.to(); |
+ if (from > char_mask) continue; |
+ if (to > char_mask) to = char_mask; |
+ // Here we are combining more ranges into the mask and compare |
+ // value. With each new range the mask becomes more sparse and |
+ // so the chances of a false positive rise. A character class |
+ // with multiple ranges is assumed never to be equivalent to a |
+ // mask and compare operation. |
+ pos->determines_perfectly = false; |
+ uint32_t new_common_bits = (from ^ to); |
+ new_common_bits = ~SmearBitsRight(new_common_bits); |
+ common_bits &= new_common_bits; |
+ bits &= new_common_bits; |
+ uint32_t differing_bits = (from & common_bits) ^ bits; |
+ common_bits ^= differing_bits; |
+ bits &= common_bits; |
+ } |
+ pos->mask = common_bits; |
+ pos->value = bits; |
+ } |
+ characters_filled_in++; |
+ ASSERT(characters_filled_in <= details->characters()); |
+ if (characters_filled_in == details->characters()) { |
+ return; |
+ } |
+ } |
+ } |
+ ASSERT(characters_filled_in != details->characters()); |
+ if (!details->cannot_match()) { |
+ on_success()-> GetQuickCheckDetails(details, |
+ compiler, |
+ characters_filled_in, |
+ true); |
+ } |
+} |
+ |
+ |
+void LoopChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details, |
+ RegExpCompiler* compiler, |
+ intptr_t characters_filled_in, |
+ bool not_at_start) { |
+ if (body_can_be_zero_length_ || info()->visited) return; |
+ VisitMarker marker(info()); |
+ return ChoiceNode::GetQuickCheckDetails(details, |
+ compiler, |
+ characters_filled_in, |
+ not_at_start); |
+} |
+ |
+ |
+intptr_t TextNode::Length() { |
+ TextElement elm = elms_->Last(); |
+ ASSERT(elm.cp_offset() >= 0); |
+ return elm.cp_offset() + elm.length(); |
+} |
+ |
+ |
+bool TextNode::SkipPass(intptr_t intptr_t_pass, bool ignore_case) { |
+ TextEmitPassType pass = static_cast<TextEmitPassType>(intptr_t_pass); |
+ if (ignore_case) { |
+ return pass == SIMPLE_CHARACTER_MATCH; |
+ } else { |
+ return pass == NON_LETTER_CHARACTER_MATCH || pass == CASE_CHARACTER_MATCH; |
+ } |
+} |
+ |
+ |
+static bool CompareInverseRanges(ZoneGrowableArray<CharacterRange>* ranges, |
+ const intptr_t* special_class, |
+ intptr_t length) { |
+ length--; // Remove final 0x10000. |
+ ASSERT(special_class[length] == 0x10000); |
+ ASSERT(ranges->length() != 0); |
+ ASSERT(length != 0); |
+ ASSERT(special_class[0] != 0); |
+ if (ranges->length() != (length >> 1) + 1) { |
+ return false; |
+ } |
+ CharacterRange range = ranges->At(0); |
+ if (range.from() != 0) { |
+ return false; |
+ } |
+ for (intptr_t 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() != 0xffff) { |
+ return false; |
+ } |
+ return true; |
+} |
+ |
+ |
+static bool CompareRanges(ZoneGrowableArray<CharacterRange>* ranges, |
+ const intptr_t* special_class, |
+ intptr_t length) { |
+ length--; // Remove final 0x10000. |
+ ASSERT(special_class[length] == 0x10000); |
+ if (ranges->length() * 2 != length) { |
+ return false; |
+ } |
+ for (intptr_t 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() { |
+ // 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(), kSpaceRanges, kSpaceRangeCount)) { |
+ set_.set_standard_set_type('s'); |
+ return true; |
+ } |
+ if (CompareInverseRanges(set_.ranges(), kSpaceRanges, kSpaceRangeCount)) { |
+ set_.set_standard_set_type('S'); |
+ return true; |
+ } |
+ if (CompareInverseRanges(set_.ranges(), |
+ kLineTerminatorRanges, |
+ kLineTerminatorRangeCount)) { |
+ set_.set_standard_set_type('.'); |
+ return true; |
+ } |
+ if (CompareRanges(set_.ranges(), |
+ kLineTerminatorRanges, |
+ kLineTerminatorRangeCount)) { |
+ set_.set_standard_set_type('n'); |
+ return true; |
+ } |
+ if (CompareRanges(set_.ranges(), kWordRanges, kWordRangeCount)) { |
+ set_.set_standard_set_type('w'); |
+ return true; |
+ } |
+ if (CompareInverseRanges(set_.ranges(), kWordRanges, kWordRangeCount)) { |
+ set_.set_standard_set_type('W'); |
+ return true; |
+ } |
+ return false; |
+} |
+ |
+ |
+void TextNode::MakeCaseIndependent(bool is_ascii) { |
+ intptr_t element_count = elms_->length(); |
+ for (intptr_t i = 0; i < element_count; i++) { |
+ TextElement elm = elms_->At(i); |
+ if (elm.text_type() == TextElement::CHAR_CLASS) { |
+ RegExpCharacterClass* cc = elm.char_class(); |
+ // None of the standard character classes is different in the case |
+ // independent case and it slows us down if we don't know that. |
+ if (cc->is_standard()) continue; |
+ ZoneGrowableArray<CharacterRange>* ranges = cc->ranges(); |
+ intptr_t range_count = ranges->length(); |
+ for (intptr_t j = 0; j < range_count; j++) { |
+ (*ranges)[j].AddCaseEquivalents(ranges, is_ascii, I); |
+ } |
+ } |
+ } |
+} |
+ |
+ |
+intptr_t TextNode::GreedyLoopTextLength() { |
+ TextElement elm = elms_->At(elms_->length() - 1); |
+ return elm.cp_offset() + elm.length(); |
+} |
+ |
+ |
+RegExpNode* TextNode::GetSuccessorOfOmnivorousTextNode( |
+ RegExpCompiler* compiler) { |
+ if (elms_->length() != 1) return NULL; |
+ TextElement elm = elms_->At(0); |
+ if (elm.text_type() != TextElement::CHAR_CLASS) return NULL; |
+ RegExpCharacterClass* node = elm.char_class(); |
+ ZoneGrowableArray<CharacterRange>* ranges = node->ranges(); |
+ if (!CharacterRange::IsCanonical(ranges)) { |
+ CharacterRange::Canonicalize(ranges); |
+ } |
+ if (node->is_negated()) { |
+ return ranges->length() == 0 ? on_success() : NULL; |
+ } |
+ if (ranges->length() != 1) return NULL; |
+ uint32_t max_char; |
+ if (compiler->ascii()) { |
+ max_char = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ max_char = Utf16::kMaxCodeUnit; |
+ } |
+ return ranges->At(0).IsEverything(max_char) ? on_success() : NULL; |
+} |
+ |
+ |
+ActionNode* ActionNode::SetRegister(intptr_t reg, |
+ intptr_t val, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(SET_REGISTER, on_success); |
+ result->data_.u_store_register.reg = reg; |
+ result->data_.u_store_register.value = val; |
+ return result; |
+} |
+ |
+ |
+ActionNode* ActionNode::IncrementRegister(intptr_t reg, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(INCREMENT_REGISTER, on_success); |
+ result->data_.u_increment_register.reg = reg; |
+ return result; |
+} |
+ |
+ |
+ActionNode* ActionNode::StorePosition(intptr_t reg, |
+ bool is_capture, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(STORE_POSITION, on_success); |
+ result->data_.u_position_register.reg = reg; |
+ result->data_.u_position_register.is_capture = is_capture; |
+ return result; |
+} |
+ |
+ |
+ActionNode* ActionNode::ClearCaptures(Interval range, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(CLEAR_CAPTURES, on_success); |
+ result->data_.u_clear_captures.range_from = range.from(); |
+ result->data_.u_clear_captures.range_to = range.to(); |
+ return result; |
+} |
+ |
+ |
+ActionNode* ActionNode::BeginSubmatch(intptr_t stack_reg, |
+ intptr_t position_reg, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(BEGIN_SUBMATCH, on_success); |
+ result->data_.u_submatch.stack_pointer_register = stack_reg; |
+ result->data_.u_submatch.current_position_register = position_reg; |
+ return result; |
+} |
+ |
+ |
+ActionNode* ActionNode::PositiveSubmatchSuccess(intptr_t stack_reg, |
+ intptr_t position_reg, |
+ intptr_t clear_register_count, |
+ intptr_t clear_register_from, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(POSITIVE_SUBMATCH_SUCCESS, |
+ on_success); |
+ result->data_.u_submatch.stack_pointer_register = stack_reg; |
+ result->data_.u_submatch.current_position_register = position_reg; |
+ result->data_.u_submatch.clear_register_count = clear_register_count; |
+ result->data_.u_submatch.clear_register_from = clear_register_from; |
+ return result; |
+} |
+ |
+ |
+ActionNode* ActionNode::EmptyMatchCheck(intptr_t start_register, |
+ intptr_t repetition_register, |
+ intptr_t repetition_limit, |
+ RegExpNode* on_success) { |
+ ActionNode* result = |
+ new(on_success->isolate()) ActionNode(EMPTY_MATCH_CHECK, on_success); |
+ result->data_.u_empty_match_check.start_register = start_register; |
+ result->data_.u_empty_match_check.repetition_register = repetition_register; |
+ result->data_.u_empty_match_check.repetition_limit = repetition_limit; |
+ return result; |
+} |
+ |
+ |
+TextElement TextElement::Atom(RegExpAtom* atom) { |
+ return TextElement(ATOM, atom); |
+} |
+ |
+ |
+TextElement TextElement::CharClass(RegExpCharacterClass* char_class) { |
+ return TextElement(CHAR_CLASS, char_class); |
+} |
+ |
+ |
+intptr_t TextElement::length() const { |
+ switch (text_type()) { |
+ case ATOM: |
+ return atom()->length(); |
+ |
+ case CHAR_CLASS: |
+ return 1; |
+ } |
+ UNREACHABLE(); |
+ return 0; |
+} |
+ |
+ |
+static void AddClass(const intptr_t* elmv, |
+ intptr_t elmc, |
+ ZoneGrowableArray<CharacterRange>* ranges) { |
+ elmc--; |
+ ASSERT(elmv[elmc] == 0x10000); |
+ for (intptr_t i = 0; i < elmc; i += 2) { |
+ ASSERT(elmv[i] < elmv[i + 1]); |
+ ranges->Add(CharacterRange(elmv[i], elmv[i + 1] - 1)); |
+ } |
+} |
+ |
+ |
+static void AddClassNegated(const intptr_t *elmv, |
+ intptr_t elmc, |
+ ZoneGrowableArray<CharacterRange>* ranges) { |
+ elmc--; |
+ ASSERT(elmv[elmc] == 0x10000); |
+ ASSERT(elmv[0] != 0x0000); |
+ ASSERT(elmv[elmc-1] != Utf16::kMaxCodeUnit); |
+ uint16_t last = 0x0000; |
+ for (intptr_t i = 0; i < elmc; i += 2) { |
+ ASSERT(last <= elmv[i] - 1); |
+ ASSERT(elmv[i] < elmv[i + 1]); |
+ ranges->Add(CharacterRange(last, elmv[i] - 1)); |
+ last = elmv[i + 1]; |
+ } |
+ ranges->Add(CharacterRange(last, Utf16::kMaxCodeUnit)); |
+} |
+ |
+ |
+void CharacterRange::AddClassEscape(uint16_t type, |
+ ZoneGrowableArray<CharacterRange>* ranges) { |
+ switch (type) { |
+ case 's': |
+ AddClass(kSpaceRanges, kSpaceRangeCount, ranges); |
+ break; |
+ case 'S': |
+ AddClassNegated(kSpaceRanges, kSpaceRangeCount, ranges); |
+ break; |
+ case 'w': |
+ AddClass(kWordRanges, kWordRangeCount, ranges); |
+ break; |
+ case 'W': |
+ AddClassNegated(kWordRanges, kWordRangeCount, ranges); |
+ break; |
+ case 'd': |
+ AddClass(kDigitRanges, kDigitRangeCount, ranges); |
+ break; |
+ case 'D': |
+ AddClassNegated(kDigitRanges, kDigitRangeCount, ranges); |
+ break; |
+ case '.': |
+ AddClassNegated(kLineTerminatorRanges, |
+ kLineTerminatorRangeCount, |
+ ranges); |
+ 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()); |
+ break; |
+ // This is the set of characters matched by the $ and ^ symbols |
+ // in multiline mode. |
+ case 'n': |
+ AddClass(kLineTerminatorRanges, |
+ kLineTerminatorRangeCount, |
+ ranges); |
+ break; |
+ default: |
+ UNREACHABLE(); |
+ } |
+} |
+ |
+ |
+// Move a number of elements in a zonelist to another position |
+// in the same list. Handles overlapping source and target areas. |
+static void MoveRanges(ZoneGrowableArray<CharacterRange>* list, |
+ intptr_t from, |
+ intptr_t to, |
+ intptr_t count) { |
+ // Ranges are potentially overlapping. |
+ if (from < to) { |
+ for (intptr_t i = count - 1; i >= 0; i--) { |
+ (*list)[to + i] = list->At(from + i); |
+ } |
+ } else { |
+ for (intptr_t i = 0; i < count; i++) { |
+ (*list)[to + i] = list->At(from + i); |
+ } |
+ } |
+} |
+ |
+ |
+static intptr_t InsertRangeInCanonicalList( |
+ ZoneGrowableArray<CharacterRange>* list, |
+ intptr_t 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. |
+ uint16_t from = insert.from(); |
+ uint16_t to = insert.to(); |
+ intptr_t start_pos = 0; |
+ intptr_t end_pos = count; |
+ for (intptr_t 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)[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); |
+ intptr_t new_from = Utils::Minimum(to_replace.from(), from); |
+ intptr_t new_to = Utils::Maximum(to_replace.to(), to); |
+ (*list)[start_pos] = CharacterRange(new_from, new_to); |
+ return count; |
+ } |
+ // Replace a number of existing ranges from start_pos to end_pos - 1. |
+ // Move the remaining ranges down. |
+ |
+ intptr_t new_from = Utils::Minimum(list->At(start_pos).from(), from); |
+ intptr_t new_to = Utils::Maximum(list->At(end_pos - 1).to(), to); |
+ if (end_pos < count) { |
+ MoveRanges(list, end_pos, start_pos + 1, count - end_pos); |
+ } |
+ (*list)[start_pos] = CharacterRange(new_from, new_to); |
+ return count - (end_pos - start_pos) + 1; |
+} |
+ |
+ |
+bool CharacterRange::IsCanonical(ZoneGrowableArray<CharacterRange>* ranges) { |
+ ASSERT(ranges != NULL); |
+ intptr_t n = ranges->length(); |
+ if (n <= 1) return true; |
+ intptr_t max = ranges->At(0).to(); |
+ for (intptr_t 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; |
+} |
+ |
+ |
+void CharacterRange::Canonicalize( |
+ ZoneGrowableArray<CharacterRange>* character_ranges) { |
+ if (character_ranges->length() <= 1) return; |
+ // Check whether ranges are already canonical (increasing, non-overlapping, |
+ // non-adjacent). |
+ intptr_t n = character_ranges->length(); |
+ intptr_t max = character_ranges->At(0).to(); |
+ intptr_t 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. |
+ intptr_t read = i; // Range to insert. |
+ intptr_t 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->TruncateTo(num_canonical); |
+ |
+ ASSERT(CharacterRange::IsCanonical(character_ranges)); |
+} |
+ |
+ |
+void CharacterSet::Canonicalize() { |
+ // Special/default classes are always considered canonical. The result |
+ // of calling ranges() will be sorted. |
+ if (ranges_ == NULL) return; |
+ CharacterRange::Canonicalize(ranges_); |
+} |
+ |
+ |
+ZoneGrowableArray<CharacterRange>* CharacterSet::ranges() { |
+ if (ranges_ == NULL) { |
+ ranges_ = new ZoneGrowableArray<CharacterRange>(2); |
+ CharacterRange::AddClassEscape(standard_set_type_, ranges_); |
+ } |
+ return ranges_; |
+} |
+ |
+ |
+void CharacterRange::Negate(ZoneGrowableArray<CharacterRange>* ranges, |
+ ZoneGrowableArray<CharacterRange>* negated_ranges) { |
+ ASSERT(CharacterRange::IsCanonical(ranges)); |
+ ASSERT(negated_ranges->length() == 0); |
+ intptr_t range_count = ranges->length(); |
+ uint16_t from = 0; |
+ intptr_t i = 0; |
+ if (range_count > 0 && ranges->At(0).from() == 0) { |
+ from = ranges->At(0).to(); |
+ i = 1; |
+ } |
+ while (i < range_count) { |
+ CharacterRange range = ranges->At(i); |
+ negated_ranges->Add(CharacterRange(from + 1, range.from() - 1)); |
+ from = range.to(); |
+ i++; |
+ } |
+ if (from < Utf16::kMaxCodeUnit) { |
+ negated_ranges->Add(CharacterRange(from + 1, Utf16::kMaxCodeUnit)); |
+ } |
+} |
+ |
+ |
+void CharacterRange::AddCaseEquivalents( |
+ ZoneGrowableArray<CharacterRange>* ranges, |
+ bool is_ascii, |
+ Isolate* isolate) { |
+ uint16_t bottom = from(); |
+ uint16_t top = to(); |
+ if (is_ascii && !RangeContainsLatin1Equivalents(*this)) { |
+ if (bottom > Symbols::kMaxOneCharCodeSymbol) return; |
+ if (top > Symbols::kMaxOneCharCodeSymbol) { |
+ top = Symbols::kMaxOneCharCodeSymbol; |
+ } |
+ } |
+ |
+ unibrow::Mapping<unibrow::Ecma262UnCanonicalize> jsregexp_uncanonicalize; |
+ unibrow::Mapping<unibrow::CanonicalizationRange> jsregexp_canonrange; |
+ int32_t chars[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
+ if (top == bottom) { |
+ // If this is a singleton we just expand the one character. |
+ intptr_t length = jsregexp_uncanonicalize.get(bottom, '\0', chars); // NOLINT |
+ for (intptr_t i = 0; i < length; i++) { |
+ uint32_t chr = chars[i]; |
+ if (chr != bottom) { |
+ ranges->Add(CharacterRange::Singleton(chars[i])); |
+ } |
+ } |
+ } 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 // NOLINT |
+ // 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"). |
+ int32_t range[unibrow::Ecma262UnCanonicalize::kMaxWidth]; |
+ intptr_t pos = bottom; |
+ while (pos <= top) { |
+ intptr_t length = jsregexp_canonrange.get(pos, '\0', range); |
+ uint16_t block_end; |
+ if (length == 0) { |
+ block_end = pos; |
+ } else { |
+ ASSERT(length == 1); |
+ block_end = range[0]; |
+ } |
+ intptr_t end = (block_end > top) ? top : block_end; |
+ length = jsregexp_uncanonicalize.get(block_end, '\0', range); // NOLINT |
+ for (intptr_t i = 0; i < length; i++) { |
+ uint32_t c = range[i]; |
+ uint16_t range_from = c - (block_end - pos); |
+ uint16_t range_to = c - (block_end - end); |
+ if (!(bottom <= range_from && range_to <= top)) { |
+ ranges->Add(CharacterRange(range_from, range_to)); |
+ } |
+ } |
+ pos = end + 1; |
+ } |
+ } |
+} |
+ |
+ |
+// ------------------------------------------------------------------- |
+// Splay tree |
+ |
+ |
+// Workaround for the fact that ZoneGrowableArray does not have contains(). |
+static bool ArrayContains(ZoneGrowableArray<unsigned>* array, |
+ unsigned value) { |
+ for (intptr_t i = 0; i < array->length(); i++) { |
+ if (array->At(i) == value) { |
+ return true; |
+ } |
+ } |
+ return false; |
+} |
+ |
+ |
+void OutSet::Set(unsigned value, Isolate* isolate) { |
+ if (value < kFirstLimit) { |
+ first_ |= (1 << value); |
+ } else { |
+ if (remaining_ == NULL) |
+ remaining_ = new(isolate) ZoneGrowableArray<unsigned>(1); |
+ |
+ bool remaining_contains_value = ArrayContains(remaining_, value); |
+ if (remaining_->is_empty() || !remaining_contains_value) { |
+ remaining_->Add(value); |
+ } |
+ } |
+} |
+ |
+ |
+bool OutSet::Get(unsigned value) const { |
+ if (value < kFirstLimit) { |
+ return (first_ & (1 << value)) != 0; |
+ } else if (remaining_ == NULL) { |
+ return false; |
+ } else { |
+ return ArrayContains(remaining_, value); |
+ } |
+} |
+ |
+void AssertionNode::GetQuickCheckDetails(QuickCheckDetails* details, |
+ RegExpCompiler* compiler, |
+ intptr_t filled_in, |
+ bool not_at_start) { |
+ if (assertion_type_ == AT_START && not_at_start) { |
+ details->set_cannot_match(); |
+ return; |
+ } |
+ return on_success()->GetQuickCheckDetails(details, |
+ compiler, |
+ filled_in, |
+ not_at_start); |
+} |
+ |
+ |
+void GuardedAlternative::AddGuard(Guard* guard, Isolate* isolate) { |
+ if (guards_ == NULL) |
+ guards_ = new(isolate) ZoneGrowableArray<Guard*>(1); |
+ guards_->Add(guard); |
+} |
+ |
+ |
+void LoopChoiceNode::AddLoopAlternative(GuardedAlternative alt) { |
+ ASSERT(loop_node_ == NULL); |
+ AddAlternative(alt); |
+ loop_node_ = alt.node(); |
+} |
+ |
+ |
+void LoopChoiceNode::AddContinueAlternative(GuardedAlternative alt) { |
+ ASSERT(continue_node_ == NULL); |
+ AddAlternative(alt); |
+ continue_node_ = alt.node(); |
+} |
+ |
+ |
+void LoopChoiceNode::Accept(NodeVisitor* visitor) { |
+ visitor->VisitLoopChoice(this); |
+} |
+ |
+ |
+intptr_t LoopChoiceNode::EatsAtLeast(intptr_t still_to_find, |
+ intptr_t budget, |
+ bool not_at_start) { |
+ return EatsAtLeastHelper(still_to_find, |
+ budget - 1, |
+ loop_node_, |
+ not_at_start); |
+} |
+ |
+ |
+void ChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details, |
+ RegExpCompiler* compiler, |
+ intptr_t characters_filled_in, |
+ bool not_at_start) { |
+ not_at_start = (not_at_start || not_at_start_); |
+ intptr_t choice_count = alternatives_->length(); |
+ ASSERT(choice_count > 0); |
+ (*alternatives_)[0].node()->GetQuickCheckDetails(details, |
+ compiler, |
+ characters_filled_in, |
+ not_at_start); |
+ for (intptr_t i = 1; i < choice_count; i++) { |
+ QuickCheckDetails new_details(details->characters()); |
+ RegExpNode* node = (*alternatives_)[i].node(); |
+ node->GetQuickCheckDetails(&new_details, compiler, |
+ characters_filled_in, |
+ not_at_start); |
+ // Here we merge the quick match details of the two branches. |
+ details->Merge(&new_details, characters_filled_in); |
+ } |
+} |
+ |
+ |
+void QuickCheckDetails::Clear() { |
+ for (intptr_t i = 0; i < characters_; i++) { |
+ positions_[i].mask = 0; |
+ positions_[i].value = 0; |
+ positions_[i].determines_perfectly = false; |
+ } |
+ characters_ = 0; |
+} |
+ |
+ |
+void QuickCheckDetails::Advance(intptr_t by, bool ascii) { |
+ ASSERT(by >= 0); |
+ if (by >= characters_) { |
+ Clear(); |
+ return; |
+ } |
+ for (intptr_t i = 0; i < characters_ - by; i++) { |
+ positions_[i] = positions_[by + i]; |
+ } |
+ for (intptr_t i = characters_ - by; i < characters_; i++) { |
+ positions_[i].mask = 0; |
+ positions_[i].value = 0; |
+ positions_[i].determines_perfectly = false; |
+ } |
+ characters_ -= by; |
+ // We could change mask_ and value_ here but we would never advance unless |
+ // they had already been used in a check and they won't be used again because |
+ // it would gain us nothing. So there's no point. |
+} |
+ |
+ |
+void QuickCheckDetails::Merge(QuickCheckDetails* other, intptr_t from_index) { |
+ ASSERT(characters_ == other->characters_); |
+ if (other->cannot_match_) { |
+ return; |
+ } |
+ if (cannot_match_) { |
+ *this = *other; |
+ return; |
+ } |
+ for (intptr_t i = from_index; i < characters_; i++) { |
+ QuickCheckDetails::Position* pos = positions(i); |
+ QuickCheckDetails::Position* other_pos = other->positions(i); |
+ if (pos->mask != other_pos->mask || |
+ pos->value != other_pos->value || |
+ !other_pos->determines_perfectly) { |
+ // Our mask-compare operation will be approximate unless we have the |
+ // exact same operation on both sides of the alternation. |
+ pos->determines_perfectly = false; |
+ } |
+ pos->mask &= other_pos->mask; |
+ pos->value &= pos->mask; |
+ other_pos->value &= pos->mask; |
+ uint16_t differing_bits = (pos->value ^ other_pos->value); |
+ pos->mask &= ~differing_bits; |
+ pos->value &= pos->mask; |
+ } |
+} |
+ |
+ |
+// Finds the fixed match length of a sequence of nodes that goes from |
+// this alternative and back to this choice node. If there are variable |
+// length nodes or other complications in the way then return a sentinel |
+// value indicating that a greedy loop cannot be constructed. |
+intptr_t ChoiceNode::GreedyLoopTextLengthForAlternative( |
+ GuardedAlternative* alternative) { |
+ intptr_t length = 0; |
+ RegExpNode* node = alternative->node(); |
+ // Later we will generate code for all these text nodes using recursion |
+ // so we have to limit the max number. |
+ intptr_t recursion_depth = 0; |
+ while (node != this) { |
+ if (recursion_depth++ > RegExpCompiler::kMaxRecursion) { |
+ return kNodeIsTooComplexForGreedyLoops; |
+ } |
+ intptr_t node_length = node->GreedyLoopTextLength(); |
+ if (node_length == kNodeIsTooComplexForGreedyLoops) { |
+ return kNodeIsTooComplexForGreedyLoops; |
+ } |
+ length += node_length; |
+ SeqRegExpNode* seq_node = static_cast<SeqRegExpNode*>(node); |
+ node = seq_node->on_success(); |
+ } |
+ return length; |
+} |
+ |
+ |
+void NegativeLookaheadChoiceNode::GetQuickCheckDetails( |
+ QuickCheckDetails* details, |
+ RegExpCompiler* compiler, |
+ intptr_t filled_in, |
+ bool not_at_start) { |
+ // Alternative 0 is the negative lookahead, alternative 1 is what comes |
+ // afterwards. |
+ RegExpNode* node = (*alternatives_)[1].node(); |
+ return node->GetQuickCheckDetails(details, compiler, filled_in, not_at_start); |
+} |
+ |
+ |
+static RegExpEngine::CompilationResult IrregexpRegExpTooBig() { |
+ return RegExpEngine::CompilationResult("RegExp too big"); |
+} |
+ |
+ |
+// Attempts to compile the regexp using an Irregexp code generator. Returns |
+// a fixed array or a null handle depending on whether it succeeded. |
+RegExpCompiler::RegExpCompiler(intptr_t capture_count, bool ignore_case, |
+ intptr_t specialization_cid) |
+ : next_register_(2 * (capture_count + 1)), |
+ work_list_(NULL), |
+ recursion_depth_(0), |
+ ignore_case_(ignore_case), |
+ specialization_cid_(specialization_cid), |
+ reg_exp_too_big_(false), |
+ current_expansion_factor_(1), |
+ isolate_(Isolate::Current()) { |
+ accept_ = new(I) EndNode(EndNode::ACCEPT, I); |
+} |
+ |
+ |
+RegExpEngine::CompilationResult RegExpCompiler::Assemble( |
+ IRRegExpMacroAssembler* macro_assembler, |
+ RegExpNode* start, |
+ intptr_t capture_count, |
+ const String& pattern) { |
+ static const bool use_slow_safe_regexp_compiler = false; |
+ |
+ macro_assembler->set_slow_safe(use_slow_safe_regexp_compiler); |
+ macro_assembler_ = macro_assembler; |
+ |
+ ZoneGrowableArray<RegExpNode*> work_list(0); |
+ work_list_ = &work_list; |
+ BlockLabel fail; |
+ macro_assembler_->PushBacktrack(&fail); |
+ Trace new_trace; |
+ start->Emit(this, &new_trace); |
+ macro_assembler_->BindBlock(&fail); |
+ macro_assembler_->Fail(); |
+ while (!work_list.is_empty()) { |
+ work_list.RemoveLast()->Emit(this, &new_trace); |
+ } |
+ if (reg_exp_too_big_) return IrregexpRegExpTooBig(); |
+ |
+ macro_assembler->FinalizeIndirectGotos(); |
+ |
+ return RegExpEngine::CompilationResult(macro_assembler, |
+ macro_assembler->graph_entry(), |
+ macro_assembler->num_blocks(), |
+ macro_assembler->num_stack_locals()); |
+} |
+ |
+ |
+RegExpEngine::CompilationResult RegExpEngine::Compile( |
+ RegExpCompileData* data, |
+ const ParsedFunction* parsed_function, |
+ const ZoneGrowableArray<const ICData*>& ic_data_array) { |
+ Isolate* isolate = Isolate::Current(); |
+ |
+ const Function& function = parsed_function->function(); |
+ const intptr_t specialization_cid = function.regexp_cid(); |
+ const bool is_ascii = (specialization_cid == kOneByteStringCid || |
+ specialization_cid == kExternalOneByteStringCid); |
+ JSRegExp& regexp = JSRegExp::Handle(isolate, function.regexp()); |
+ const String& pattern = String::Handle(isolate, regexp.pattern()); |
+ |
+ ASSERT(!regexp.IsNull()); |
+ ASSERT(!pattern.IsNull()); |
+ |
+ const bool ignore_case = regexp.is_ignore_case(); |
+ const bool is_global = regexp.is_global(); |
+ |
+ RegExpCompiler compiler(data->capture_count, ignore_case, specialization_cid); |
+ |
+ // TODO(jgruber): Frequency sampling is currently disabled because of several |
+ // issues. We do not want to store subject strings in the regexp object since |
+ // they might be long and we should not prevent their garbage collection. |
+ // Passing them to this function explicitly does not help, since we must |
+ // generate exactly the same IR for both the unoptimizing and optimizing |
+ // pipelines (otherwise it gets confused when i.e. deopt id's differ). |
+ // An option would be to store sampling results in the regexp object, but |
+ // I'm not sure the performance gains are relevant enough. |
+ |
+ // Wrap the body of the regexp in capture #0. |
+ RegExpNode* captured_body = RegExpCapture::ToNode(data->tree, |
+ 0, |
+ &compiler, |
+ compiler.accept()); |
+ |
+ RegExpNode* node = captured_body; |
+ bool is_start_anchored = data->tree->IsAnchoredAtStart(); |
+ bool is_end_anchored = data->tree->IsAnchoredAtEnd(); |
+ intptr_t max_length = data->tree->max_match(); |
+ if (!is_start_anchored) { |
+ // Add a .*? at the beginning, outside the body capture, unless |
+ // this expression is anchored at the beginning. |
+ RegExpNode* loop_node = |
+ RegExpQuantifier::ToNode(0, |
+ RegExpTree::kInfinity, |
+ false, |
+ new(isolate) RegExpCharacterClass('*'), |
+ &compiler, |
+ captured_body, |
+ data->contains_anchor); |
+ |
+ if (data->contains_anchor) { |
+ // Unroll loop once, to take care of the case that might start |
+ // at the start of input. |
+ ChoiceNode* first_step_node = new(isolate) ChoiceNode(2, isolate); |
+ first_step_node->AddAlternative(GuardedAlternative(captured_body)); |
+ first_step_node->AddAlternative(GuardedAlternative( |
+ new(isolate) TextNode( |
+ new(isolate) RegExpCharacterClass('*'), loop_node))); |
+ node = first_step_node; |
+ } else { |
+ node = loop_node; |
+ } |
+ } |
+ if (is_ascii) { |
+ node = node->FilterASCII(RegExpCompiler::kMaxRecursion, ignore_case); |
+ // Do it again to propagate the new nodes to places where they were not |
+ // put because they had not been calculated yet. |
+ if (node != NULL) { |
+ node = node->FilterASCII(RegExpCompiler::kMaxRecursion, ignore_case); |
+ } |
+ } |
+ |
+ if (node == NULL) node = new(isolate) EndNode(EndNode::BACKTRACK, isolate); |
+ data->node = node; |
+ Analysis analysis(ignore_case, is_ascii); |
+ analysis.EnsureAnalyzed(node); |
+ if (analysis.has_failed()) { |
+ const char* error_message = analysis.error_message(); |
+ return CompilationResult(error_message); |
+ } |
+ |
+ // Native regexp implementation. |
+ |
+ IRRegExpMacroAssembler* macro_assembler = |
+ new(isolate) IRRegExpMacroAssembler(specialization_cid, |
+ data->capture_count, |
+ parsed_function, |
+ ic_data_array, |
+ isolate); |
+ |
+ // Inserted here, instead of in Assembler, because it depends on information |
+ // in the AST that isn't replicated in the Node structure. |
+ static const intptr_t kMaxBacksearchLimit = 1024; |
+ if (is_end_anchored && |
+ !is_start_anchored && |
+ max_length < kMaxBacksearchLimit) { |
+ macro_assembler->SetCurrentPositionFromEnd(max_length); |
+ } |
+ |
+ if (is_global) { |
+ macro_assembler->set_global_mode( |
+ (data->tree->min_match() > 0) |
+ ? RegExpMacroAssembler::GLOBAL_NO_ZERO_LENGTH_CHECK |
+ : RegExpMacroAssembler::GLOBAL); |
+ } |
+ |
+ RegExpEngine::CompilationResult result = |
+ compiler.Assemble(macro_assembler, |
+ node, |
+ data->capture_count, |
+ pattern); |
+ |
+ if (FLAG_trace_irregexp) { |
+ macro_assembler->PrintBlocks(); |
+ } |
+ |
+ return result; |
+} |
+ |
+ |
+static void CreateSpecializedFunction(Isolate* isolate, |
+ const JSRegExp& regexp, |
+ intptr_t specialization_cid, |
+ const Object& owner) { |
+ const intptr_t kParamCount = RegExpMacroAssembler::kParamCount; |
+ |
+ Function& fn = Function::Handle(isolate, |
+ Function::New(String::Handle(isolate, Symbols::New("RegExp")), |
+ RawFunction::kIrregexpFunction, |
+ true, // Static. |
+ false, // Not const. |
+ false, // Not abstract. |
+ false, // Not external. |
+ false, // Not native. |
+ owner, |
+ 0)); // Requires a non-negative token position. |
+ |
+ // TODO(jgruber): Share these arrays between all irregexp functions. |
+ fn.set_num_fixed_parameters(kParamCount); |
+ fn.set_parameter_types(Array::Handle(isolate, Array::New(kParamCount, |
+ Heap::kOld))); |
+ fn.set_parameter_names(Array::Handle(isolate, Array::New(kParamCount, |
+ Heap::kOld))); |
+ fn.SetParameterTypeAt(0, Type::Handle(isolate, Type::DynamicType())); |
+ fn.SetParameterNameAt(0, Symbols::string_param_()); |
+ fn.SetParameterTypeAt(1, Type::Handle(isolate, Type::DynamicType())); |
+ fn.SetParameterNameAt(1, Symbols::start_index_param_()); |
+ fn.set_result_type(Type::Handle(isolate, Type::ArrayType())); |
+ |
+ // Cache the result. |
+ regexp.set_function(specialization_cid, fn); |
+ |
+ fn.set_regexp(regexp); |
+ fn.set_regexp_cid(specialization_cid); |
+ |
+ // The function is compiled lazily during the first call. |
+} |
+ |
+ |
+RawJSRegExp* RegExpEngine::CreateJSRegExp(Isolate* isolate, |
+ const String& pattern, |
+ bool multi_line, |
+ bool ignore_case) { |
+ const JSRegExp& regexp = JSRegExp::Handle(JSRegExp::New(0)); |
+ |
+ regexp.set_pattern(pattern); |
+ |
+ if (multi_line) { |
+ regexp.set_is_multi_line(); |
+ } |
+ if (ignore_case) { |
+ regexp.set_is_ignore_case(); |
+ } |
+ |
+ // TODO(jgruber): We might want to use normal string searching algorithms |
+ // for simple patterns. |
+ regexp.set_is_complex(); |
+ regexp.set_is_global(); // All dart regexps are global. |
+ |
+ const Library& lib = Library::Handle(isolate, Library::CoreLibrary()); |
+ const Class& owner = Class::Handle(isolate, |
+ lib.LookupClass(String::Handle(isolate, Symbols::New("RegExp")))); |
+ |
+ CreateSpecializedFunction(isolate, regexp, kOneByteStringCid, owner); |
+ CreateSpecializedFunction(isolate, regexp, kTwoByteStringCid, owner); |
+ CreateSpecializedFunction(isolate, regexp, kExternalOneByteStringCid, owner); |
+ CreateSpecializedFunction(isolate, regexp, kExternalTwoByteStringCid, owner); |
+ |
+ return regexp.raw(); |
+} |
+ |
+ |
+void BoyerMoorePositionInfo::Set(intptr_t character) { |
+ SetInterval(Interval(character, character)); |
+} |
+ |
+ |
+ContainedInLattice AddRange(ContainedInLattice containment, |
+ const intptr_t* ranges, |
+ intptr_t ranges_length, |
+ Interval new_range) { |
+ ASSERT((ranges_length & 1) == 1); |
+ ASSERT(ranges[ranges_length - 1] == Utf16::kMaxCodeUnit + 1); |
+ if (containment == kLatticeUnknown) return containment; |
+ bool inside = false; |
+ intptr_t last = 0; |
+ for (intptr_t i = 0; i < ranges_length; |
+ inside = !inside, last = ranges[i], i++) { |
+ // Consider the range from last to ranges[i]. |
+ // We haven't got to the new range yet. |
+ if (ranges[i] <= new_range.from()) continue; |
+ // New range is wholly inside last-ranges[i]. Note that new_range.to() is |
+ // inclusive, but the values in ranges are not. |
+ if (last <= new_range.from() && new_range.to() < ranges[i]) { |
+ return Combine(containment, inside ? kLatticeIn : kLatticeOut); |
+ } |
+ return kLatticeUnknown; |
+ } |
+ return containment; |
+} |
+ |
+ |
+void BoyerMoorePositionInfo::SetInterval(const Interval& interval) { |
+ s_ = AddRange(s_, kSpaceRanges, kSpaceRangeCount, interval); |
+ w_ = AddRange(w_, kWordRanges, kWordRangeCount, interval); |
+ d_ = AddRange(d_, kDigitRanges, kDigitRangeCount, interval); |
+ surrogate_ = |
+ AddRange(surrogate_, kSurrogateRanges, kSurrogateRangeCount, interval); |
+ if (interval.to() - interval.from() >= kMapSize - 1) { |
+ if (map_count_ != kMapSize) { |
+ map_count_ = kMapSize; |
+ for (intptr_t i = 0; i < kMapSize; i++) (*map_)[i] = true; |
+ } |
+ return; |
+ } |
+ for (intptr_t i = interval.from(); i <= interval.to(); i++) { |
+ intptr_t mod_character = (i & kMask); |
+ if (!map_->At(mod_character)) { |
+ map_count_++; |
+ (*map_)[mod_character] = true; |
+ } |
+ if (map_count_ == kMapSize) return; |
+ } |
+} |
+ |
+ |
+void BoyerMoorePositionInfo::SetAll() { |
+ s_ = w_ = d_ = kLatticeUnknown; |
+ if (map_count_ != kMapSize) { |
+ map_count_ = kMapSize; |
+ for (intptr_t i = 0; i < kMapSize; i++) (*map_)[i] = true; |
+ } |
+} |
+ |
+ |
+BoyerMooreLookahead::BoyerMooreLookahead( |
+ intptr_t length, RegExpCompiler* compiler, Isolate* isolate) |
+ : length_(length), |
+ compiler_(compiler) { |
+ if (compiler->ascii()) { |
+ max_char_ = Symbols::kMaxOneCharCodeSymbol; |
+ } else { |
+ max_char_ = Utf16::kMaxCodeUnit; |
+ } |
+ bitmaps_ = new(isolate) ZoneGrowableArray<BoyerMoorePositionInfo*>(length); |
+ for (intptr_t i = 0; i < length; i++) { |
+ bitmaps_->Add(new(isolate) BoyerMoorePositionInfo(isolate)); |
+ } |
+} |
+ |
+ |
+// Take all the characters that will not prevent a successful match if they |
+// occur in the subject string in the range between min_lookahead and |
+// max_lookahead (inclusive) measured from the current position. If the |
+// character at max_lookahead offset is not one of these characters, then we |
+// can safely skip forwards by the number of characters in the range. |
+intptr_t BoyerMooreLookahead::GetSkipTable( |
+ intptr_t min_lookahead, |
+ intptr_t max_lookahead, |
+ const TypedData& boolean_skip_table) { |
+ const intptr_t kSize = RegExpMacroAssembler::kTableSize; |
+ |
+ const intptr_t kSkipArrayEntry = 0; |
+ const intptr_t kDontSkipArrayEntry = 1; |
+ |
+ for (intptr_t i = 0; i < kSize; i++) { |
+ boolean_skip_table.SetUint8(i, kSkipArrayEntry); |
+ } |
+ intptr_t skip = max_lookahead + 1 - min_lookahead; |
+ |
+ for (intptr_t i = max_lookahead; i >= min_lookahead; i--) { |
+ BoyerMoorePositionInfo* map = bitmaps_->At(i); |
+ for (intptr_t j = 0; j < kSize; j++) { |
+ if (map->at(j)) { |
+ boolean_skip_table.SetUint8(j, kDontSkipArrayEntry); |
+ } |
+ } |
+ } |
+ |
+ return skip; |
+} |
+ |
+ |
+// Find the longest range of lookahead that has the fewest number of different |
+// characters that can occur at a given position. Since we are optimizing two |
+// different parameters at once this is a tradeoff. |
+bool BoyerMooreLookahead::FindWorthwhileInterval(intptr_t* from, intptr_t* to) { |
+ intptr_t biggest_points = 0; |
+ // If more than 32 characters out of 128 can occur it is unlikely that we can |
+ // be lucky enough to step forwards much of the time. |
+ const intptr_t kMaxMax = 32; |
+ for (intptr_t max_number_of_chars = 4; |
+ max_number_of_chars < kMaxMax; |
+ max_number_of_chars *= 2) { |
+ biggest_points = |
+ FindBestInterval(max_number_of_chars, biggest_points, from, to); |
+ } |
+ if (biggest_points == 0) return false; |
+ return true; |
+} |
+ |
+ |
+// Find the highest-points range between 0 and length_ where the character |
+// information is not too vague. 'Too vague' means that there are more than |
+// max_number_of_chars that can occur at this position. Calculates the number |
+// of points as the product of width-of-the-range and |
+// probability-of-finding-one-of-the-characters, where the probability is |
+// calculated using the frequency distribution of the sample subject string. |
+intptr_t BoyerMooreLookahead::FindBestInterval( |
+ intptr_t max_number_of_chars, |
+ intptr_t old_biggest_points, |
+ intptr_t* from, |
+ intptr_t* to) { |
+ intptr_t biggest_points = old_biggest_points; |
+ static const intptr_t kSize = RegExpMacroAssembler::kTableSize; |
+ for (intptr_t i = 0; i < length_; ) { |
+ while (i < length_ && Count(i) > max_number_of_chars) i++; |
+ if (i == length_) break; |
+ intptr_t remembered_from = i; |
+ bool union_map[kSize]; |
+ for (intptr_t j = 0; j < kSize; j++) union_map[j] = false; |
+ while (i < length_ && Count(i) <= max_number_of_chars) { |
+ BoyerMoorePositionInfo* map = bitmaps_->At(i); |
+ for (intptr_t j = 0; j < kSize; j++) union_map[j] |= map->at(j); |
+ i++; |
+ } |
+ intptr_t frequency = 0; |
+ for (intptr_t j = 0; j < kSize; j++) { |
+ if (union_map[j]) { |
+ // Add 1 to the frequency to give a small per-character boost for |
+ // the cases where our sampling is not good enough and many |
+ // characters have a frequency of zero. This means the frequency |
+ // can theoretically be up to 2*kSize though we treat it mostly as |
+ // a fraction of kSize. |
+ frequency += compiler_->frequency_collator()->Frequency(j) + 1; |
+ } |
+ } |
+ // We use the probability of skipping times the distance we are skipping to |
+ // judge the effectiveness of this. Actually we have a cut-off: By |
+ // dividing by 2 we switch off the skipping if the probability of skipping |
+ // is less than 50%. This is because the multibyte mask-and-compare |
+ // skipping in quickcheck is more likely to do well on this case. |
+ bool in_quickcheck_range = ((i - remembered_from < 4) || |
+ (compiler_->ascii() ? remembered_from <= 4 : remembered_from <= 2)); |
+ // Called 'probability' but it is only a rough estimate and can actually |
+ // be outside the 0-kSize range. |
+ intptr_t probability = |
+ (in_quickcheck_range ? kSize / 2 : kSize) - frequency; |
+ intptr_t points = (i - remembered_from) * probability; |
+ if (points > biggest_points) { |
+ *from = remembered_from; |
+ *to = i - 1; |
+ biggest_points = points; |
+ } |
+ } |
+ return biggest_points; |
+} |
+ |
+ |
+// See comment above on the implementation of GetSkipTable. |
+bool BoyerMooreLookahead::EmitSkipInstructions(RegExpMacroAssembler* masm) { |
+ const intptr_t kSize = RegExpMacroAssembler::kTableSize; |
+ |
+ intptr_t min_lookahead = 0; |
+ intptr_t max_lookahead = 0; |
+ |
+ if (!FindWorthwhileInterval(&min_lookahead, &max_lookahead)) return false; |
+ |
+ bool found_single_character = false; |
+ intptr_t single_character = 0; |
+ for (intptr_t i = max_lookahead; i >= min_lookahead; i--) { |
+ BoyerMoorePositionInfo* map = bitmaps_->At(i); |
+ if (map->map_count() > 1 || |
+ (found_single_character && map->map_count() != 0)) { |
+ found_single_character = false; |
+ break; |
+ } |
+ for (intptr_t j = 0; j < kSize; j++) { |
+ if (map->at(j)) { |
+ found_single_character = true; |
+ single_character = j; |
+ break; |
+ } |
+ } |
+ } |
+ |
+ intptr_t lookahead_width = max_lookahead + 1 - min_lookahead; |
+ |
+ if (found_single_character && lookahead_width == 1 && max_lookahead < 3) { |
+ // The mask-compare can probably handle this better. |
+ return false; |
+ } |
+ |
+ if (found_single_character) { |
+ BlockLabel cont, again; |
+ masm->BindBlock(&again); |
+ masm->LoadCurrentCharacter(max_lookahead, &cont, true); |
+ if (max_char_ > kSize) { |
+ masm->CheckCharacterAfterAnd(single_character, |
+ RegExpMacroAssembler::kTableMask, |
+ &cont); |
+ } else { |
+ masm->CheckCharacter(single_character, &cont); |
+ } |
+ masm->AdvanceCurrentPosition(lookahead_width); |
+ masm->GoTo(&again); |
+ masm->BindBlock(&cont); |
+ return true; |
+ } |
+ |
+ const TypedData& boolean_skip_table = TypedData::ZoneHandle( |
+ compiler_->isolate(), |
+ TypedData::New(kTypedDataUint8ArrayCid, kSize, Heap::kOld)); |
+ intptr_t skip_distance = GetSkipTable( |
+ min_lookahead, max_lookahead, boolean_skip_table); |
+ ASSERT(skip_distance != 0); |
+ |
+ BlockLabel cont, again; |
+ |
+ masm->BindBlock(&again); |
+ masm->LoadCurrentCharacter(max_lookahead, &cont, true); |
+ masm->CheckBitInTable(boolean_skip_table, &cont); |
+ masm->AdvanceCurrentPosition(skip_distance); |
+ masm->GoTo(&again); |
+ masm->BindBlock(&cont); |
+ |
+ return true; |
+} |
+ |
+ |
+// ------------------------------------------------------------------- |
+// Analysis |
+ |
+ |
+void Analysis::EnsureAnalyzed(RegExpNode* that) { |
+ if (that->info()->been_analyzed || that->info()->being_analyzed) |
+ return; |
+ that->info()->being_analyzed = true; |
+ that->Accept(this); |
+ that->info()->being_analyzed = false; |
+ that->info()->been_analyzed = true; |
+} |
+ |
+ |
+void Analysis::VisitEnd(EndNode* that) { |
+ // nothing to do |
+} |
+ |
+ |
+void TextNode::CalculateOffsets() { |
+ intptr_t element_count = elements()->length(); |
+ // Set up the offsets of the elements relative to the start. This is a fixed |
+ // quantity since a TextNode can only contain fixed-width things. |
+ intptr_t cp_offset = 0; |
+ for (intptr_t i = 0; i < element_count; i++) { |
+ TextElement& elm = (*elements())[i]; |
+ elm.set_cp_offset(cp_offset); |
+ cp_offset += elm.length(); |
+ } |
+} |
+ |
+ |
+void Analysis::VisitText(TextNode* that) { |
+ if (ignore_case_) { |
+ that->MakeCaseIndependent(is_ascii_); |
+ } |
+ EnsureAnalyzed(that->on_success()); |
+ if (!has_failed()) { |
+ that->CalculateOffsets(); |
+ } |
+} |
+ |
+ |
+void Analysis::VisitAction(ActionNode* that) { |
+ RegExpNode* target = that->on_success(); |
+ EnsureAnalyzed(target); |
+ if (!has_failed()) { |
+ // If the next node is interested in what it follows then this node |
+ // has to be interested too so it can pass the information on. |
+ that->info()->AddFromFollowing(target->info()); |
+ } |
+} |
+ |
+ |
+void Analysis::VisitChoice(ChoiceNode* that) { |
+ NodeInfo* info = that->info(); |
+ for (intptr_t i = 0; i < that->alternatives()->length(); i++) { |
+ RegExpNode* node = (*that->alternatives())[i].node(); |
+ EnsureAnalyzed(node); |
+ if (has_failed()) return; |
+ // Anything the following nodes need to know has to be known by |
+ // this node also, so it can pass it on. |
+ info->AddFromFollowing(node->info()); |
+ } |
+} |
+ |
+ |
+void Analysis::VisitLoopChoice(LoopChoiceNode* that) { |
+ NodeInfo* info = that->info(); |
+ for (intptr_t i = 0; i < that->alternatives()->length(); i++) { |
+ RegExpNode* node = (*that->alternatives())[i].node(); |
+ if (node != that->loop_node()) { |
+ EnsureAnalyzed(node); |
+ if (has_failed()) return; |
+ info->AddFromFollowing(node->info()); |
+ } |
+ } |
+ // Check the loop last since it may need the value of this node |
+ // to get a correct result. |
+ EnsureAnalyzed(that->loop_node()); |
+ if (!has_failed()) { |
+ info->AddFromFollowing(that->loop_node()->info()); |
+ } |
+} |
+ |
+ |
+void Analysis::VisitBackReference(BackReferenceNode* that) { |
+ EnsureAnalyzed(that->on_success()); |
+} |
+ |
+ |
+void Analysis::VisitAssertion(AssertionNode* that) { |
+ EnsureAnalyzed(that->on_success()); |
+} |
+ |
+ |
+// ------------------------------------------------------------------- |
+// Dot/dotty output |
+ |
+ |
+#ifdef DEBUG |
+ |
+ |
+class DotPrinter: public NodeVisitor { |
+ public: |
+ explicit DotPrinter(bool ignore_case) |
+ : ignore_case_(ignore_case) {} |
+ void PrintNode(const char* label, RegExpNode* node); |
+ void Visit(RegExpNode* node); |
+ void PrintAttributes(RegExpNode* from); |
+ void PrintOnFailure(RegExpNode* from, RegExpNode* to); |
+#define DECLARE_VISIT(Type) \ |
+ virtual void Visit##Type(Type##Node* that); |
+FOR_EACH_NODE_TYPE(DECLARE_VISIT) |
+#undef DECLARE_VISIT |
+ private: |
+ bool ignore_case_; |
+}; |
+ |
+ |
+void DotPrinter::PrintNode(const char* label, RegExpNode* node) { |
+ OS::Print("digraph G {\n graph [label=\""); |
+ for (intptr_t i = 0; label[i]; i++) { |
+ switch (label[i]) { |
+ case '\\': |
+ OS::Print("\\\\"); |
+ break; |
+ case '"': |
+ OS::Print("\""); |
+ break; |
+ default: |
+ OS::Print("%c", label[i]); |
+ break; |
+ } |
+ } |
+ OS::Print("\"];\n"); |
+ Visit(node); |
+ OS::Print("}\n"); |
+} |
+ |
+ |
+void DotPrinter::Visit(RegExpNode* node) { |
+ if (node->info()->visited) return; |
+ node->info()->visited = true; |
+ node->Accept(this); |
+} |
+ |
+ |
+void DotPrinter::PrintOnFailure(RegExpNode* from, RegExpNode* on_failure) { |
+ OS::Print(" n%p -> n%p [style=dotted];\n", from, on_failure); |
+ Visit(on_failure); |
+} |
+ |
+ |
+class AttributePrinter : public ValueObject { |
+ public: |
+ AttributePrinter() : first_(true) {} |
+ void PrintSeparator() { |
+ if (first_) { |
+ first_ = false; |
+ } else { |
+ OS::Print("|"); |
+ } |
+ } |
+ void PrintBit(const char* name, bool value) { |
+ if (!value) return; |
+ PrintSeparator(); |
+ OS::Print("{%s}", name); |
+ } |
+ void PrintPositive(const char* name, intptr_t value) { |
+ if (value < 0) return; |
+ PrintSeparator(); |
+ OS::Print("{%s|%" Pd "}", name, value); |
+ } |
+ |
+ private: |
+ bool first_; |
+}; |
+ |
+ |
+void DotPrinter::PrintAttributes(RegExpNode* that) { |
+ OS::Print(" a%p [shape=Mrecord, color=grey, fontcolor=grey, " |
+ "margin=0.1, fontsize=10, label=\"{", that); |
+ AttributePrinter printer; |
+ NodeInfo* info = that->info(); |
+ printer.PrintBit("NI", info->follows_newline_interest); |
+ printer.PrintBit("WI", info->follows_word_interest); |
+ printer.PrintBit("SI", info->follows_start_interest); |
+ BlockLabel* label = that->label(); |
+ if (label->IsBound()) |
+ printer.PrintPositive("@", label->Position()); |
+ OS::Print("}\"];\n" |
+ " a%p -> n%p [style=dashed, color=grey, arrowhead=none];\n", |
+ that, that); |
+} |
+ |
+ |
+static const bool kPrintDispatchTable = false; |
+void DotPrinter::VisitChoice(ChoiceNode* that) { |
+ if (kPrintDispatchTable) { |
+ OS::Print(" n%p [shape=Mrecord, label=\"", that); |
+ UNIMPLEMENTED(); |
+ } else { |
+ OS::Print(" n%p [shape=Mrecord, label=\"?\"];\n", that); |
+ for (intptr_t i = 0; i < that->alternatives()->length(); i++) { |
+ GuardedAlternative alt = that->alternatives()->At(i); |
+ OS::Print(" n%p -> n%p", that, alt.node()); |
+ } |
+ } |
+ for (intptr_t i = 0; i < that->alternatives()->length(); i++) { |
+ GuardedAlternative alt = that->alternatives()->At(i); |
+ alt.node()->Accept(this); |
+ } |
+} |
+ |
+ |
+void DotPrinter::VisitText(TextNode* that) { |
+ OS::Print(" n%p [label=\"", that); |
+ for (intptr_t i = 0; i < that->elements()->length(); i++) { |
+ if (i > 0) OS::Print(" "); |
+ TextElement elm = that->elements()->At(i); |
+ switch (elm.text_type()) { |
+ case TextElement::ATOM: { |
+ ZoneGrowableArray<uint16_t>* data = elm.atom()->data(); |
+ for (intptr_t i = 0; i < data->length(); i++) { |
+ OS::Print("%c", static_cast<char>(data->At(i))); |
+ } |
+ break; |
+ } |
+ case TextElement::CHAR_CLASS: { |
+ RegExpCharacterClass* node = elm.char_class(); |
+ OS::Print("["); |
+ if (node->is_negated()) OS::Print("^"); |
+ for (intptr_t j = 0; j < node->ranges()->length(); j++) { |
+ CharacterRange range = node->ranges()->At(j); |
+ PrintUtf16(range.from()); |
+ OS::Print("-"); |
+ PrintUtf16(range.to()); |
+ } |
+ OS::Print("]"); |
+ break; |
+ } |
+ default: |
+ UNREACHABLE(); |
+ } |
+ } |
+ OS::Print("\", shape=box, peripheries=2];\n"); |
+ PrintAttributes(that); |
+ OS::Print(" n%p -> n%p;\n", that, that->on_success()); |
+ Visit(that->on_success()); |
+} |
+ |
+ |
+void DotPrinter::VisitBackReference(BackReferenceNode* that) { |
+ OS::Print(" n%p [label=\"$%" Pd "..$%" Pd "\", shape=doubleoctagon];\n", |
+ that, that->start_register(), that->end_register()); |
+ PrintAttributes(that); |
+ OS::Print(" n%p -> n%p;\n", that, that->on_success()); |
+ Visit(that->on_success()); |
+} |
+ |
+ |
+void DotPrinter::VisitEnd(EndNode* that) { |
+ OS::Print(" n%p [style=bold, shape=point];\n", that); |
+ PrintAttributes(that); |
+} |
+ |
+ |
+void DotPrinter::VisitAssertion(AssertionNode* that) { |
+ OS::Print(" n%p [", that); |
+ switch (that->assertion_type()) { |
+ case AssertionNode::AT_END: |
+ OS::Print("label=\"$\", shape=septagon"); |
+ break; |
+ case AssertionNode::AT_START: |
+ OS::Print("label=\"^\", shape=septagon"); |
+ break; |
+ case AssertionNode::AT_BOUNDARY: |
+ OS::Print("label=\"\\b\", shape=septagon"); |
+ break; |
+ case AssertionNode::AT_NON_BOUNDARY: |
+ OS::Print("label=\"\\B\", shape=septagon"); |
+ break; |
+ case AssertionNode::AFTER_NEWLINE: |
+ OS::Print("label=\"(?<=\\n)\", shape=septagon"); |
+ break; |
+ } |
+ OS::Print("];\n"); |
+ PrintAttributes(that); |
+ RegExpNode* successor = that->on_success(); |
+ OS::Print(" n%p -> n%p;\n", that, successor); |
+ Visit(successor); |
+} |
+ |
+ |
+void DotPrinter::VisitAction(ActionNode* that) { |
+ OS::Print(" n%p [", that); |
+ switch (that->action_type_) { |
+ case ActionNode::SET_REGISTER: |
+ OS::Print("label=\"$%" Pd ":=%" Pd "\", shape=octagon", |
+ that->data_.u_store_register.reg, |
+ that->data_.u_store_register.value); |
+ break; |
+ case ActionNode::INCREMENT_REGISTER: |
+ OS::Print("label=\"$%" Pd "++\", shape=octagon", |
+ that->data_.u_increment_register.reg); |
+ break; |
+ case ActionNode::STORE_POSITION: |
+ OS::Print("label=\"$%" Pd ":=$pos\", shape=octagon", |
+ that->data_.u_position_register.reg); |
+ break; |
+ case ActionNode::BEGIN_SUBMATCH: |
+ OS::Print("label=\"$%" Pd ":=$pos,begin\", shape=septagon", |
+ that->data_.u_submatch.current_position_register); |
+ break; |
+ case ActionNode::POSITIVE_SUBMATCH_SUCCESS: |
+ OS::Print("label=\"escape\", shape=septagon"); |
+ break; |
+ case ActionNode::EMPTY_MATCH_CHECK: |
+ OS::Print("label=\"$%" Pd "=$pos?,$%" Pd "<%" Pd "?\", shape=septagon", |
+ that->data_.u_empty_match_check.start_register, |
+ that->data_.u_empty_match_check.repetition_register, |
+ that->data_.u_empty_match_check.repetition_limit); |
+ break; |
+ case ActionNode::CLEAR_CAPTURES: { |
+ OS::Print("label=\"clear $%" Pd " to $%" Pd "\", shape=septagon", |
+ that->data_.u_clear_captures.range_from, |
+ that->data_.u_clear_captures.range_to); |
+ break; |
+ } |
+ } |
+ OS::Print("];\n"); |
+ PrintAttributes(that); |
+ RegExpNode* successor = that->on_success(); |
+ OS::Print(" n%p -> n%p;\n", that, successor); |
+ Visit(successor); |
+} |
+ |
+ |
+void RegExpEngine::DotPrint(const char* label, |
+ RegExpNode* node, |
+ bool ignore_case) { |
+ DotPrinter printer(ignore_case); |
+ printer.PrintNode(label, node); |
+} |
+ |
+ |
+#endif // DEBUG |
+ |
+} // namespace dart |