fix(parser): prevent adaptive-set stack overflow - #144
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@codex review |
Copy/Paste DetectionFound 17 duplication(s) across 2 changed Rust file(s) (threshold: 100 tokens). Show duplicationsFound a 27 line (145 tokens) duplication in the following files:
fn generated_match_token_recovers_missing_token_from_context_follow() {
let atn = generated_match_recovery_atn();
let data = RecognizerData::new(
"Mini.g4",
Vocabulary::new(
[None, Some("'X'"), Some("'Y'")],
[None, Some("X"), Some("Y")],
[None::<&str>, None, None],
),
);
let mut parser = BaseParser::new(
CommonTokenStream::new(Source {
tokens: vec![TestToken::eof("parser-test", 3, 1, 3)],
index: 0,
}),
data,
);
parser.rule_context_stack = vec![
RuleContextFrame {
rule_index: 0,
invoking_state: 0,
},
RuleContextFrame {
rule_index: 1,
invoking_state: 1,
},
];Found a 27 line (127 tokens) duplication in the following files:
let mut atn = ParserAtnBuilder::new(2);
assert_eq!(
atn.add_state(AtnStateKind::RuleStart, Some(0))
.expect("state")
.index(),
0
);
assert_eq!(
atn.add_state(AtnStateKind::BlockStart, Some(0))
.expect("state")
.index(),
1
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))
.expect("state")
.index(),
2
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))
.expect("state")
.index(),
3
);
assert_eq!(
atn.add_state(AtnStateKind::BlockEnd, Some(0))Found a 33 line (126 tokens) duplication in the following files:
if self.fast_parser_predicate_matches(predicate_context, transition, index) {
let boundary = left_recursive_boundary(atn, state, target);
outcomes.extend(
self.recognize_state_fast(
atn,
FastRecognizeRequest {
state_number: target,
stop_state,
index,
rule_start_index,
decision_start_index: next_decision_start_index,
precedence,
depth: depth + 1,
recovery_symbols: Rc::clone(&epsilon_recovery_symbols),
recovery_state: epsilon_recovery_state,
},
FastRecognizeScratch {
predicate_context,
visiting,
memo,
expected,
},
)
.into_iter()
.map(|mut outcome| {
if let Some(rule_index) = boundary {
let boundary = self.arena_boundary_node(rule_index);
self.defer_fast_outcome_node(&mut outcome, boundary);
}
outcome
}),
);
} else {Found a 32 line (125 tokens) duplication in the following files:
let boundary = left_recursive_boundary(atn, state, target);
outcomes.extend(
self.recognize_state_fast(
atn,
FastRecognizeRequest {
state_number: target,
stop_state,
index,
rule_start_index,
decision_start_index: next_decision_start_index,
precedence,
depth: depth + 1,
recovery_symbols: Rc::clone(&epsilon_recovery_symbols),
recovery_state: epsilon_recovery_state,
},
FastRecognizeScratch {
predicate_context,
visiting,
memo,
expected,
},
)
.into_iter()
.map(|mut outcome| {
if let Some(rule_index) = boundary {
let boundary = self.arena_boundary_node(rule_index);
self.defer_fast_outcome_node(&mut outcome, boundary);
}
outcome
}),
);
}Found a 22 line (125 tokens) duplication in the following files:
atn.add_state(AtnStateKind::BlockEnd, Some(0))
.expect("state")
.index(),
4
);
assert_eq!(
atn.add_state(AtnStateKind::RuleStop, Some(0))
.expect("state")
.index(),
5
);
atn.set_rule_to_start_state(vec![0])
.expect("rule start states");
atn.set_rule_to_stop_state(vec![5])
.expect("rule stop states");
atn.add_decision_state(1).expect("decision state");
atn.add_transition(0, ParserTransitionSpec::Epsilon { target: 1 })
.expect("transition");
atn.add_transition(
1,
ParserTransitionSpec::Atom {
target: 2,Found a 33 line (115 tokens) duplication in the following files:
outcomes.extend(
self.recognize_state(
atn,
RecognizeRequest {
state_number: *target,
stop_state,
index,
rule_start_index,
decision_start_index: next_decision_start_index,
init_action_rules,
predicates,
semantics,
rule_args,
member_actions,
return_actions,
local_int_arg,
member_values: member_values.clone(),
return_values: return_values.clone(),
rule_alt_number: next_alt_number,
track_alt_numbers,
consumed_eof,
precedence,
depth: depth + 1,
recovery_symbols: epsilon_recovery_symbols.clone(),
recovery_state: epsilon_recovery_state,
},
visiting,
memo,
expected,
)
.into_iter()
.map(|mut outcome| {
prepend_decision(&mut outcome, decision);Found a 15 line (113 tokens) duplication in the following files:
fn generated_match_token_counts_single_token_deletion_recovery() {
let atn = generated_match_recovery_atn();
let data = RecognizerData::new(
"Mini.g4",
Vocabulary::new(
[None, Some("'X'"), Some("'Y'"), Some("'Z'")],
[None, Some("X"), Some("Y"), Some("Z")],
[None::<&str>, None, None, None],
),
);
let mut parser = BaseParser::new(
CommonTokenStream::new(Source {
tokens: vec![
TestToken::new(3).with_text("z"),
TestToken::new(2).with_text("y"),Found a 12 line (112 tokens) duplication in the following files:
let mut atn = ParserAtnBuilder::new(1);
for (state, kind, rule) in [
(0, AtnStateKind::RuleStart, 0),
(1, AtnStateKind::StarLoopEntry, 0),
(2, AtnStateKind::Basic, 0), // ops hub
(3, AtnStateKind::Basic, 0), // shift prec
(4, AtnStateKind::Basic, 0), // shift first >
(5, AtnStateKind::Basic, 0), // shift second >
(6, AtnStateKind::Basic, 0), // rel prec
(7, AtnStateKind::Basic, 0), // rel >
(8, AtnStateKind::LoopEnd, 0),
(9, AtnStateKind::RuleStop, 0),Found a 22 line (112 tokens) duplication in the following files:
fn predicate_after_token_atn() -> Atn {
let mut atn = ParserAtnBuilder::new(2);
assert_eq!(
atn.add_state(AtnStateKind::RuleStart, Some(0))
.expect("state")
.index(),
0
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))
.expect("state")
.index(),
1
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))
.expect("state")
.index(),
2
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))Found a 22 line (111 tokens) duplication in the following files:
fn left_recursive_loop_with_caller_follow_atn(caller_symbol: i32) -> Atn {
let mut atn = ParserAtnBuilder::new(2);
assert_eq!(
atn.add_state(AtnStateKind::RuleStart, Some(0))
.expect("state")
.index(),
0
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))
.expect("state")
.index(),
1
);
assert_eq!(
atn.add_state(AtnStateKind::Basic, Some(0))
.expect("state")
.index(),
2
);
assert_eq!(
atn.add_state(AtnStateKind::RuleStart, Some(1))Found a 14 line (110 tokens) duplication in the following files:
fn parser_matches_token_and_reports_mismatch() {
let source = Source {
tokens: vec![
TestToken::new(1).with_text("x"),
TestToken::eof("parser-test", 1, 1, 1),
],
index: 0,
};
let data = RecognizerData::new(
"Mini.g4",
Vocabulary::new([None, Some("'x'")], [None, Some("X")], [None::<&str>, None]),
);
let mut parser = BaseParser::new(CommonTokenStream::new(source), data);
let matched = parser.match_token(1).expect("token 1 should match");Found a 13 line (109 tokens) duplication in the following files:
fn parser_matches_token_and_reports_mismatch() {
let source = Source {
tokens: vec![
TestToken::new(1).with_text("x"),
TestToken::eof("parser-test", 1, 1, 1),
],
index: 0,
};
let data = RecognizerData::new(
"Mini.g4",
Vocabulary::new([None, Some("'x'")], [None, Some("X")], [None::<&str>, None]),
);
let mut parser = BaseParser::new(CommonTokenStream::new(source), data);Found a 22 line (108 tokens) duplication in the following files:
) -> Option<RecognizeOutcome> {
let (error_index, message) = self.expected_error_message(rule_index, start_index, expected);
let diagnostic = diagnostic_for_token(self.token_at(error_index), message);
let mut next_index = error_index;
loop {
let symbol = self.token_type_at(next_index);
if sync_symbols.contains(&symbol) {
if next_index == error_index {
return None;
}
break;
}
if symbol == TOKEN_EOF {
break;
}
let after = self.consume_index(next_index, symbol);
if after == next_index {
break;
}
next_index = after;
}
let mut nodes = NodeSeqId::EMPTY;Found a 15 line (108 tokens) duplication in the following files:
fn outcome_ties_keep_later_non_recursive_alternative() {
let arena = RecognitionArena::default();
let first = RecognizeOutcome {
index: 1,
consumed_eof: false,
alt_number: 0,
member_values: BTreeMap::new(),
return_values: BTreeMap::new(),
diagnostics: DiagnosticSeqId::EMPTY,
decisions: Vec::new(),
actions: vec![ParserAction::new(1, 0, 0, None)],
nodes: NodeSeqId::EMPTY,
};
let second = RecognizeOutcome {
actions: vec![ParserAction::new(2, 0, 0, None)],Found a 16 line (105 tokens) duplication in the following files:
let start_state = atn.rule_to_start_state().get(rule_index).ok_or_else(|| {
AntlrError::Unsupported(format!("rule {rule_index} has no start state"))
})?;
let stop_state = atn
.rule_to_stop_state()
.get(rule_index)
.filter(|state| *state != usize::MAX)
.ok_or_else(|| {
AntlrError::Unsupported(format!("rule {rule_index} has no stop state"))
})?;
let start_index = self.current_visible_index();
self.clear_prediction_diagnostics();
self.reset_per_parse_caches();
self.reset_recognition_arena();
let caller_follow_state = self.pending_invoking_follow_state(atn);Found a 15 line (104 tokens) duplication in the following files:
impl ParserTransitionData<'_> {
pub const fn target(self) -> usize {
match self {
Self::Epsilon { target }
| Self::Atom { target, .. }
| Self::Range { target, .. }
| Self::Set { target, .. }
| Self::NotSet { target, .. }
| Self::Wildcard { target }
| Self::Rule { target, .. }
| Self::Predicate { target, .. }
| Self::Action { target, .. }
| Self::Precedence { target, .. } => target,
}
}Found a 13 line (100 tokens) duplication in the following files:
let mut expected = BTreeSet::new();
for index in (1..self.rule_context_stack.len()).rev() {
let invoking_state = self.rule_context_stack[index].invoking_state;
let Ok(state_number) = usize::try_from(invoking_state) else {
continue;
};
let Some(Transition::Rule { follow_state, .. }) = atn
.state(state_number)
.and_then(|state| state.transitions().first())
.map(ParserTransition::data)
else {
continue;
}; |
|
No actionable comments were generated in the recent review. 🎉 ℹ️ Recent review info⚙️ Run configurationConfiguration used: Path: .coderabbit.yaml Review profile: ASSERTIVE Plan: Pro Run ID: 📒 Files selected for processing (2)
📝 WalkthroughWalkthroughThe parser stops forcing inlining for ChangesParser stack safety
Estimated code review effort: 2 (Simple) | ~10 minutes 🚥 Pre-merge checks | ✅ 5✅ Passed checks (5 passed)
✨ Finishing Touches📝 Generate docstrings
🧪 Generate unit tests (beta)
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Code Review
This pull request changes the inlining attribute of ParserIntervalSet::contains from #[inline(always)] to #[inline] to prevent forced inlining from bloating recursive recognizer frames in unoptimized builds. Additionally, it introduces a helper function nested_rule_chain_atn and a test nested_rule_chain_with_adaptive_set_fits_default_stack to verify that nested rule chains fit within a default 2 MiB stack size. There are no review comments, so no feedback is provided.
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Summary
ParserIntervalSet::containsinto recursive parser-recognizer framesRoot cause
ParserIntervalSet::containswas marked#[inline(always)]when adaptive parser token sets landed. In unoptimized builds, forcing that membership logic into every recursive recognizer call enlarged each stack frame enough for previously passing Kotlin analyses to overflow Rust's default test-thread stack.Using ordinary
#[inline]lets optimized builds retain the hot-path optimization while allowing debug builds to keep recursive frames small.Validation
cargo test --locked --lib: 244 passedtests/kotlin-parity/run.sh: all 9 fixtures matched Python byte-for-bytecargo run --release --quiet --bin antlr4-runtime-testsuite: 357 passedcargo clippy --locked --all-targets --all-features -- -D warningscargo fmt --checkgit diff --checkCloses #142
Summary by CodeRabbit