Title: [276527] trunk/Source/_javascript_Core
- Revision
- 276527
- Author
- msab...@apple.com
- Date
- 2021-04-23 16:06:12 -0700 (Fri, 23 Apr 2021)
Log Message
[YARR Interpreter] Improper backtrack of parentheses with non-zero based greedy quantifiers
https://bugs.webkit.org/show_bug.cgi?id=224983
Reviewed by Mark Lam.
When we backtrack a parentheses with a greedy non zero based quantifier,
we don't properly restore for the case where we hadn't reached the minimum count.
We now save the input position on entry and restore it when we backtrack for
this case. We also properly release the allocated ParenthesesDisjunctionContext's.
* yarr/YarrInterpreter.cpp:
(JSC::Yarr::Interpreter::matchParentheses):
(JSC::Yarr::Interpreter::backtrackParentheses):
Modified Paths
Diff
Modified: trunk/Source/_javascript_Core/ChangeLog (276526 => 276527)
--- trunk/Source/_javascript_Core/ChangeLog 2021-04-23 23:01:48 UTC (rev 276526)
+++ trunk/Source/_javascript_Core/ChangeLog 2021-04-23 23:06:12 UTC (rev 276527)
@@ -1,3 +1,19 @@
+2021-04-23 Michael Saboff <msab...@apple.com>
+
+ [YARR Interpreter] Improper backtrack of parentheses with non-zero based greedy quantifiers
+ https://bugs.webkit.org/show_bug.cgi?id=224983
+
+ Reviewed by Mark Lam.
+
+ When we backtrack a parentheses with a greedy non zero based quantifier,
+ we don't properly restore for the case where we hadn't reached the minimum count.
+ We now save the input position on entry and restore it when we backtrack for
+ this case. We also properly release the allocated ParenthesesDisjunctionContext's.
+
+ * yarr/YarrInterpreter.cpp:
+ (JSC::Yarr::Interpreter::matchParentheses):
+ (JSC::Yarr::Interpreter::backtrackParentheses):
+
2021-04-23 Mark Lam <mark....@apple.com>
Fix B3 strength reduction for shl.
Modified: trunk/Source/_javascript_Core/yarr/YarrInterpreter.cpp (276526 => 276527)
--- trunk/Source/_javascript_Core/yarr/YarrInterpreter.cpp 2021-04-23 23:01:48 UTC (rev 276526)
+++ trunk/Source/_javascript_Core/yarr/YarrInterpreter.cpp 2021-04-23 23:06:12 UTC (rev 276527)
@@ -45,6 +45,7 @@
struct ParenthesesDisjunctionContext;
struct BackTrackInfoParentheses {
+ uintptr_t begin;
uintptr_t matchAmount;
ParenthesesDisjunctionContext* lastContext;
};
@@ -1022,6 +1023,7 @@
BackTrackInfoParentheses* backTrack = reinterpret_cast<BackTrackInfoParentheses*>(context->frame + term.frameLocation);
ByteDisjunction* disjunctionBody = term.atom.parenthesesDisjunction;
+ backTrack->begin = input.getPos();
backTrack->matchAmount = 0;
backTrack->lastContext = nullptr;
@@ -1175,8 +1177,20 @@
popParenthesesDisjunctionContext(backTrack);
freeParenthesesDisjunctionContext(context);
- if (result != JSRegExpNoMatch || backTrack->matchAmount < term.atom.quantityMinCount)
+ if (backTrack->matchAmount < term.atom.quantityMinCount) {
+ while (backTrack->matchAmount) {
+ context = backTrack->lastContext;
+ resetMatches(term, context);
+ popParenthesesDisjunctionContext(backTrack);
+ freeParenthesesDisjunctionContext(context);
+ }
+
+ input.setPos(backTrack->begin);
return result;
+ }
+
+ if (result != JSRegExpNoMatch)
+ return result;
}
if (backTrack->matchAmount) {
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