Avoid overdeep recursion in regexp where a guarded expression with a

minimum repetition count is inside another quantifier.
Bug=129926
Review URL: https://chromiumcodereview.appspot.com/10451092

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11686 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
This commit is contained in:
erik.corry@gmail.com 2012-05-31 11:59:04 +00:00
parent b7b43e9af9
commit 047a7cfee0
3 changed files with 75 additions and 39 deletions

View File

@ -2191,12 +2191,13 @@ int ActionNode::EatsAtLeast(int still_to_find,
void ActionNode::FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
if (type_ == BEGIN_SUBMATCH) {
bm->SetRest(offset);
} else if (type_ != POSITIVE_SUBMATCH_SUCCESS) {
on_success()->FillInBMInfo(offset, bm, not_at_start);
on_success()->FillInBMInfo(offset, recursion_depth + 1, bm, not_at_start);
}
SaveBMInfo(bm, not_at_start, offset);
}
@ -2218,11 +2219,13 @@ int AssertionNode::EatsAtLeast(int still_to_find,
}
void AssertionNode::FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
void AssertionNode::FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
// Match the behaviour of EatsAtLeast on this node.
if (type() == AT_START && not_at_start) return;
on_success()->FillInBMInfo(offset, bm, not_at_start);
on_success()->FillInBMInfo(offset, recursion_depth + 1, bm, not_at_start);
SaveBMInfo(bm, not_at_start, offset);
}
@ -2803,14 +2806,17 @@ void LoopChoiceNode::GetQuickCheckDetails(QuickCheckDetails* details,
}
void LoopChoiceNode::FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
if (body_can_be_zero_length_) {
void LoopChoiceNode::FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
if (body_can_be_zero_length_ ||
recursion_depth > RegExpCompiler::kMaxRecursion) {
bm->SetRest(offset);
SaveBMInfo(bm, not_at_start, offset);
return;
}
ChoiceNode::FillInBMInfo(offset, bm, not_at_start);
ChoiceNode::FillInBMInfo(offset, recursion_depth + 1, bm, not_at_start);
SaveBMInfo(bm, not_at_start, offset);
}
@ -2912,7 +2918,7 @@ void AssertionNode::EmitBoundaryCheck(RegExpCompiler* compiler, Trace* trace) {
if (eats_at_least >= 1) {
BoyerMooreLookahead* bm =
new BoyerMooreLookahead(eats_at_least, compiler);
FillInBMInfo(0, bm, not_at_start);
FillInBMInfo(0, 0, bm, not_at_start);
if (bm->at(0)->is_non_word()) next_is_word_character = Trace::FALSE;
if (bm->at(0)->is_word()) next_is_word_character = Trace::TRUE;
}
@ -3850,7 +3856,7 @@ void ChoiceNode::Emit(RegExpCompiler* compiler, Trace* trace) {
BoyerMooreLookahead* bm =
new BoyerMooreLookahead(eats_at_least, compiler);
GuardedAlternative alt0 = alternatives_->at(0);
alt0.node()->FillInBMInfo(0, bm, not_at_start);
alt0.node()->FillInBMInfo(0, 0, bm, not_at_start);
skip_was_emitted = bm->EmitSkipInstructions(macro_assembler);
}
} else {
@ -5589,8 +5595,10 @@ void Analysis::VisitAssertion(AssertionNode* that) {
}
void BackReferenceNode::FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
void BackReferenceNode::FillInBMInfo(int offset,
int recursion_depth,
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);
@ -5602,8 +5610,10 @@ STATIC_ASSERT(BoyerMoorePositionInfo::kMapSize ==
RegExpMacroAssembler::kTableSize);
void ChoiceNode::FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
void ChoiceNode::FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
ZoneList<GuardedAlternative>* alts = alternatives();
for (int i = 0; i < alts->length(); i++) {
GuardedAlternative& alt = alts->at(i);
@ -5612,14 +5622,16 @@ void ChoiceNode::FillInBMInfo(
SaveBMInfo(bm, not_at_start, offset);
return;
}
alt.node()->FillInBMInfo(offset, bm, not_at_start);
alt.node()->FillInBMInfo(offset, recursion_depth + 1, bm, not_at_start);
}
SaveBMInfo(bm, not_at_start, offset);
}
void TextNode::FillInBMInfo(
int initial_offset, BoyerMooreLookahead* bm, bool not_at_start) {
void TextNode::FillInBMInfo(int initial_offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
if (initial_offset >= bm->length()) return;
int offset = initial_offset;
int max_char = bm->max_char();
@ -5673,6 +5685,7 @@ void TextNode::FillInBMInfo(
return;
}
on_success()->FillInBMInfo(offset,
recursion_depth + 1,
bm,
true); // Not at start after a text node.
if (initial_offset == 0) set_bm_info(not_at_start, bm);

View File

@ -581,8 +581,10 @@ class RegExpNode: public ZoneObject {
// we look forward. This is used for a Boyer-Moore-like string searching
// implementation. TODO(erikcorry): This should share more code with
// EatsAtLeast, GetQuickCheckDetails.
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
UNREACHABLE();
}
@ -681,9 +683,11 @@ class SeqRegExpNode: public RegExpNode {
RegExpNode* on_success() { return on_success_; }
void set_on_success(RegExpNode* node) { on_success_ = node; }
virtual RegExpNode* FilterASCII(int depth);
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
on_success_->FillInBMInfo(offset, bm, not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
on_success_->FillInBMInfo(offset, recursion_depth + 1, bm, not_at_start);
if (offset == 0) set_bm_info(not_at_start, bm);
}
@ -736,8 +740,10 @@ class ActionNode: public SeqRegExpNode {
return on_success()->GetQuickCheckDetails(
details, compiler, filled_in, not_at_start);
}
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start);
Type type() { return type_; }
// TODO(erikcorry): We should allow some action nodes in greedy loops.
virtual int GreedyLoopTextLength() { return kNodeIsTooComplexForGreedyLoops; }
@ -805,8 +811,10 @@ class TextNode: public SeqRegExpNode {
virtual int GreedyLoopTextLength();
virtual RegExpNode* GetSuccessorOfOmnivorousTextNode(
RegExpCompiler* compiler);
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start);
void CalculateOffsets();
virtual RegExpNode* FilterASCII(int depth);
@ -865,8 +873,10 @@ class AssertionNode: public SeqRegExpNode {
RegExpCompiler* compiler,
int filled_in,
bool not_at_start);
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start);
AssertionNodeType type() { return type_; }
void set_type(AssertionNodeType type) { type_ = type; }
@ -903,8 +913,10 @@ class BackReferenceNode: public SeqRegExpNode {
bool not_at_start) {
return;
}
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start);
private:
int start_reg_;
@ -928,8 +940,10 @@ class EndNode: public RegExpNode {
// Returning 0 from EatsAtLeast should ensure we never get here.
UNREACHABLE();
}
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
// Returning 0 from EatsAtLeast should ensure we never get here.
UNREACHABLE();
}
@ -1018,8 +1032,10 @@ class ChoiceNode: public RegExpNode {
RegExpCompiler* compiler,
int characters_filled_in,
bool not_at_start);
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start);
bool being_calculated() { return being_calculated_; }
bool not_at_start() { return not_at_start_; }
@ -1068,9 +1084,12 @@ class NegativeLookaheadChoiceNode: public ChoiceNode {
RegExpCompiler* compiler,
int characters_filled_in,
bool not_at_start);
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start) {
alternatives_->at(1).node()->FillInBMInfo(offset, bm, not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start) {
alternatives_->at(1).node()->FillInBMInfo(
offset, recursion_depth + 1, bm, not_at_start);
if (offset == 0) set_bm_info(not_at_start, bm);
}
// For a negative lookahead we don't emit the quick check for the
@ -1100,8 +1119,10 @@ class LoopChoiceNode: public ChoiceNode {
RegExpCompiler* compiler,
int characters_filled_in,
bool not_at_start);
virtual void FillInBMInfo(
int offset, BoyerMooreLookahead* bm, bool not_at_start);
virtual void FillInBMInfo(int offset,
int recursion_depth,
BoyerMooreLookahead* bm,
bool not_at_start);
RegExpNode* loop_node() { return loop_node_; }
RegExpNode* continue_node() { return continue_node_; }
bool body_can_be_zero_length() { return body_can_be_zero_length_; }

View File

@ -216,3 +216,5 @@ regex10.exec(input0);
var regex11 = /^(?:[^\u0000-\u0080]|[0-9a-z?,.!&\s#()])+$/i;
regex11.exec(input0);
var regex12 = /u(\xf0{8}?\D*?|( ? !)$h??(|)*?(||)+?\6((?:\W\B|--\d-*-|)?$){0, }?|^Y( ? !1)\d+)+a/;
regex12.exec("");