phase29an(p13): add cleanup facts scaffold and projections

src/mir/builder/control_flow/plan/facts/feature_facts.rs

@@ -23,6 +23,18 @@ pub(in crate::mir::builder) struct ExitMapFacts {
     pub kinds_present: BTreeSet<ExitKindFacts>,
 }
 
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord)]
+pub(in crate::mir::builder) enum CleanupKindFacts {
+    Return,
+    Break,
+    Continue,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub(in crate::mir::builder) struct CleanupFacts {
+    pub kinds_present: BTreeSet<CleanupKindFacts>,
+}
+
 #[derive(Debug, Clone, Default, PartialEq, Eq)]
 pub(in crate::mir::builder) struct LoopFeatureFacts {
     pub exit_usage: ExitUsageFacts,
@@ -34,8 +46,6 @@ pub(in crate::mir::builder) struct LoopFeatureFacts {
 #[derive(Debug, Clone, PartialEq, Eq)]
 pub(in crate::mir::builder) struct ValueJoinFacts;
 
-#[derive(Debug, Clone, PartialEq, Eq)]
-pub(in crate::mir::builder) struct CleanupFacts;
 
 pub(in crate::mir::builder) fn try_extract_loop_feature_facts(
     body: &[ASTNode],

src/mir/builder/control_flow/plan/normalize/canonicalize.rs

@@ -3,7 +3,7 @@
 #![allow(dead_code)]
 
 use crate::mir::builder::control_flow::plan::facts::feature_facts::{
-    ExitKindFacts, ExitUsageFacts,
+    CleanupKindFacts, ExitKindFacts, ExitUsageFacts,
 };
 use crate::mir::builder::control_flow::plan::facts::skeleton_facts::SkeletonKind;
 use crate::mir::builder::control_flow::plan::facts::LoopFacts;
@@ -15,6 +15,7 @@ pub(in crate::mir::builder) struct CanonicalLoopFacts {
     pub skeleton_kind: SkeletonKind,
     pub exit_usage: ExitUsageFacts,
     pub exit_kinds_present: BTreeSet<ExitKindFacts>,
+    pub cleanup_kinds_present: BTreeSet<CleanupKindFacts>,
 }
 
 pub(in crate::mir::builder) fn canonicalize_loop_facts(facts: LoopFacts) -> CanonicalLoopFacts {
@@ -27,6 +28,12 @@ pub(in crate::mir::builder) fn canonicalize_loop_facts(facts: LoopFacts) -> Cano
             .as_ref()
             .map(|map| map.kinds_present.clone())
             .unwrap_or_default(),
+        cleanup_kinds_present: facts
+            .features
+            .cleanup
+            .as_ref()
+            .map(|cleanup| cleanup.kinds_present.clone())
+            .unwrap_or_default(),
         facts,
     }
 }
@@ -36,7 +43,8 @@ mod tests {
     use super::canonicalize_loop_facts;
     use crate::ast::{ASTNode, BinaryOperator, LiteralValue, Span};
     use crate::mir::builder::control_flow::plan::facts::feature_facts::{
-        ExitKindFacts, ExitMapFacts, ExitUsageFacts, LoopFeatureFacts,
+        CleanupFacts, CleanupKindFacts, ExitKindFacts, ExitMapFacts, ExitUsageFacts,
+        LoopFeatureFacts,
     };
     use crate::mir::builder::control_flow::plan::facts::loop_facts::LoopFacts;
     use crate::mir::builder::control_flow::plan::facts::scan_shapes::{
@@ -65,6 +73,8 @@ mod tests {
         kinds_present.insert(ExitKindFacts::Break);
         kinds_present.insert(ExitKindFacts::Continue);
         kinds_present.insert(ExitKindFacts::Return);
+        let mut cleanup_kinds_present = BTreeSet::new();
+        cleanup_kinds_present.insert(CleanupKindFacts::Return);
         let facts = LoopFacts {
             condition_shape: ConditionShape::Unknown,
             step_shape: StepShape::Unknown,
@@ -79,7 +89,9 @@ mod tests {
                 },
                 exit_map: Some(ExitMapFacts { kinds_present }),
                 value_join: None,
-                cleanup: None,
+                cleanup: Some(CleanupFacts {
+                    kinds_present: cleanup_kinds_present,
+                }),
             },
             scan_with_init: None,
             split_scan: None,
@@ -101,6 +113,10 @@ mod tests {
         assert!(canonical.exit_kinds_present.contains(&ExitKindFacts::Break));
         assert!(canonical.exit_kinds_present.contains(&ExitKindFacts::Continue));
         assert!(canonical.exit_kinds_present.contains(&ExitKindFacts::Return));
+        assert_eq!(canonical.cleanup_kinds_present.len(), 1);
+        assert!(canonical
+            .cleanup_kinds_present
+            .contains(&CleanupKindFacts::Return));
     }
 
     #[test]
@@ -125,6 +141,7 @@ mod tests {
         };
         let canonical = canonicalize_loop_facts(facts);
         assert!(canonical.exit_kinds_present.is_empty());
+        assert!(canonical.cleanup_kinds_present.is_empty());
     }
 
     #[test]

src/mir/builder/control_flow/plan/planner/build.rs

@@ -5,7 +5,7 @@
 use crate::ast::ASTNode;
 
 use crate::mir::builder::control_flow::plan::facts::feature_facts::{
-    ExitKindFacts, ExitUsageFacts,
+    CleanupKindFacts, ExitKindFacts, ExitUsageFacts,
 };
 use crate::mir::builder::control_flow::plan::facts::skeleton_facts::SkeletonKind;
 use crate::mir::builder::control_flow::plan::normalize::CanonicalLoopFacts;
@@ -62,6 +62,10 @@ pub(in crate::mir::builder) fn build_plan_from_facts_ctx(
 
     let _skeleton_kind = infer_skeleton_kind(&facts);
     let _exit_usage = infer_exit_usage(&facts);
+    debug_assert_cleanup_kinds_match_exit_kinds(
+        &facts.cleanup_kinds_present,
+        &facts.exit_kinds_present,
+    );
 
     let mut candidates = CandidateSet::new();
 
@@ -140,6 +144,31 @@ fn debug_assert_exit_usage_matches_plan(
 ) {
 }
 
+#[cfg(debug_assertions)]
+fn debug_assert_cleanup_kinds_match_exit_kinds(
+    cleanup_kinds_present: &BTreeSet<CleanupKindFacts>,
+    exit_kinds_present: &BTreeSet<ExitKindFacts>,
+) {
+    for cleanup_kind in cleanup_kinds_present {
+        let exit_kind = match cleanup_kind {
+            CleanupKindFacts::Return => ExitKindFacts::Return,
+            CleanupKindFacts::Break => ExitKindFacts::Break,
+            CleanupKindFacts::Continue => ExitKindFacts::Continue,
+        };
+        debug_assert!(
+            exit_kinds_present.contains(&exit_kind),
+            "cleanup kind requires matching exit kind presence"
+        );
+    }
+}
+
+#[cfg(not(debug_assertions))]
+fn debug_assert_cleanup_kinds_match_exit_kinds(
+    _cleanup_kinds_present: &BTreeSet<CleanupKindFacts>,
+    _exit_kinds_present: &BTreeSet<ExitKindFacts>,
+) {
+}
+
 fn push_scan_with_init(candidates: &mut CandidateSet, facts: &CanonicalLoopFacts) {
     let Some(scan) = &facts.facts.scan_with_init else {
         return;