internal/core/adt: add generation tracking to closedness info

This change adds generation tracking to CloseInfo to prevent stale
closedness information from being used across different evaluation
contexts. Each CloseInfo now tracks the generation (opID) when it
was created, allowing the evaluator to detect and handle misaligned
conjuncts and constraints.

Key changes:
- Add opID field to CloseInfo struct for generation tracking
- Add MisalignedConjunct and MisalignedConstraint counters to stats
- Validate generation alignment when processing conjuncts/constraints
- Drop misaligned items and increment appropriate counters
- Reset opID when converting vertices in toDataAllRec

This prevents cross-generation contamination that could lead to
incorrect evaluation results or memory safety issues.

Signed-off-by: Marcel van Lohuizen <[email protected]>
Change-Id: If29fcdff2221b8295c2cb34427c34e9b3a1f4b53
Reviewed-on: https://review.gerrithub.io/c/cue-lang/cue/+/1218835
Unity-Result: CUE porcuepine <[email protected]>
Reviewed-by: Daniel Martí <[email protected]>
TryBot-Result: CUEcueckoo <[email protected]>

Author: mpvl

cmd/cue/cmd/testdata/script/stats.txtar

@@ -55,6 +55,8 @@ contents overwritten
         "MaxConjunctInfos": 2,
         "MaxReqSets": 0,
         "GenerationMismatch": 0,
+        "MisalignedConjunct": 0,
+        "MisalignedConstraint": 0,
         "Freed": 6,
         "Reused": 0,
         "Allocs": 6,
@@ -67,20 +69,22 @@ contents overwritten
 }
 -- out/stats.cue --
 CUE: {
-	EvalVersion:        3
-	Unifications:       4
-	Disjuncts:          2
-	Notifications:      0
-	Conjuncts:          8
-	NumCloseIDs:        2
-	ConjunctInfos:      6
-	MaxConjunctInfos:   2
-	MaxReqSets:         0
-	GenerationMismatch: 0
-	Freed:              6
-	Reused:             0
-	Allocs:             6
-	Retained:           0
+	EvalVersion:          3
+	Unifications:         4
+	Disjuncts:            2
+	Notifications:        0
+	Conjuncts:            8
+	NumCloseIDs:          2
+	ConjunctInfos:        6
+	MaxConjunctInfos:     2
+	MaxReqSets:           0
+	GenerationMismatch:   0
+	MisalignedConjunct:   0
+	MisalignedConstraint: 0
+	Freed:                6
+	Reused:               0
+	Allocs:               6
+	Retained:             0
 }
 Go: {
 	AllocBytes:   300456
@@ -98,6 +102,8 @@ CUE:
   MaxConjunctInfos: 2
   MaxReqSets: 0
   GenerationMismatch: 0
+  MisalignedConjunct: 0
+  MisalignedConstraint: 0
   Freed: 6
   Reused: 0
   Allocs: 6
@@ -118,6 +124,8 @@ Go:
         "MaxConjunctInfos": 2,
         "MaxReqSets": 0,
         "GenerationMismatch": 0,
+        "MisalignedConjunct": 0,
+        "MisalignedConstraint": 0,
         "Freed": 6,
         "Reused": 0,
         "Allocs": 6,

cue/stats/stats.go

@@ -83,6 +83,18 @@ type Counts struct {
 	// with a different generation than the one it was created in.
 	GenerationMismatch int64 // Number of exceptional unification cases
 
+	// MisalignedConjunct indicates the number of conjuncts that were dropped
+	// because they were not aligned with the current generation of the context.
+	// Generally this happens because a previously finalized vertex is unified
+	// in as a value, not constraint, in which case it is okay to ignore
+	// closedness info. If it were included as a schema, top-level conjuncts
+	// would be unified and mapped to a local tree.
+	MisalignedConjunct int64
+
+	// MisalignedConstraint indicates the number of constraints that were not
+	// aligned. This is more likely to be a bug.
+	MisalignedConstraint int64
+
 	// Buffer counters
 	//
 	// Each unification and disjunct operation is associated with an object
@@ -122,6 +134,8 @@ func (c *Counts) Add(other Counts) {
 	c.Notifications += other.Notifications
 
 	c.GenerationMismatch += other.GenerationMismatch
+	c.MisalignedConjunct += other.MisalignedConjunct
+	c.MisalignedConstraint += other.MisalignedConstraint
 
 	c.NumCloseIDs += other.NumCloseIDs
 	c.ConjunctInfos += other.ConjunctInfos
@@ -144,6 +158,8 @@ func (c Counts) Since(start Counts) Counts {
 	c.Disjuncts -= start.Disjuncts
 	c.Notifications -= start.Notifications
 	c.GenerationMismatch -= start.GenerationMismatch
+	c.MisalignedConjunct -= start.MisalignedConjunct
+	c.MisalignedConstraint -= start.MisalignedConstraint
 	c.NumCloseIDs -= start.NumCloseIDs
 
 	c.ConjunctInfos -= start.ConjunctInfos
@@ -177,9 +193,11 @@ Retain: {{.Retained}}
 Unifications: {{.Unifications}}
 Conjuncts:    {{.Conjuncts}}
 Disjuncts:    {{.Disjuncts}}{{if .Notifications}}
-Notifications: {{.Notifications}}{{end}}{{if .GenerationMismatch}}
-
-GenerationMismatch: {{.GenerationMismatch}}{{end}}{{if .NumCloseIDs}}
+Notifications: {{.Notifications}}{{end}}{{if or .GenerationMismatch .MisalignedConjunct .MisalignedConstraint}}
+{{if .GenerationMismatch}}
+GenerationMismatch: {{.GenerationMismatch}}{{end}}{{if .MisalignedConjunct}}
+MisalignedConjunct: {{.MisalignedConjunct}}{{end}}{{if .MisalignedConstraint}}
+MisalignedConstraint: {{.MisalignedConstraint}}{{end}}{{end}}{{if .NumCloseIDs}}
 
 NumCloseIDs: {{.NumCloseIDs}}{{end}}{{if or (ge .MaxReqSets 150) (ge .MaxConjunctInfos 8)}}
 

cue/testdata/benchmarks/issue2176.txtar

@@ -115,6 +115,8 @@ Unifications: 766
 Conjuncts:    3242
 Disjuncts:    1409
 
+MisalignedConjunct: 1216
+
 NumCloseIDs: 12
 -- out/evalalpha --
 (struct){

cue/testdata/benchmarks/issue572.txtar

@@ -53,6 +53,8 @@ Unifications: 3001
 Conjuncts:    7498
 Disjuncts:    3001
 
+MisalignedConjunct: 1498
+
 NumCloseIDs: 1
 -- out/eval --
 (struct){

cue/testdata/benchmarks/mergeddisjunction.txtar

@@ -51,6 +51,8 @@ Unifications: 99
 Conjuncts:    530
 Disjuncts:    283
 
+MisalignedConjunct: 33
+
 NumCloseIDs: 2
 -- out/eval --
 (struct){

cue/testdata/benchmarks/typocheck.txtar

@@ -73,6 +73,8 @@ Unifications: 700
 Conjuncts:    1302
 Disjuncts:    807
 
+MisalignedConjunct: 696
+
 NumCloseIDs: 4
 -- out/eval --
 (struct){

cue/testdata/builtins/validators.txtar

@@ -231,6 +231,8 @@ Unifications: 195
 Conjuncts:    351
 Disjuncts:    218
 
+MisalignedConjunct: 1
+
 NumCloseIDs: 8
 -- out/evalalpha --
 Errors:

cue/testdata/comprehensions/045_comprehension_and_skipped_field.txtar

@@ -58,6 +58,8 @@ Unifications: 8
 Conjuncts:    11
 Disjuncts:    12
 
+MisalignedConjunct: 1
+
 NumCloseIDs: 1
 -- out/eval --
 (struct){

cue/testdata/comprehensions/checkdefined.txtar

@@ -91,6 +91,8 @@ Unifications: 100
 Conjuncts:    134
 Disjuncts:    105
 
+MisalignedConjunct: 2
+
 NumCloseIDs: 13
 -- out/eval --
 (struct){

cue/testdata/comprehensions/closed.txtar

@@ -121,6 +121,8 @@ Unifications: 68
 Conjuncts:    118
 Disjuncts:    81
 
+MisalignedConjunct: 15
+
 NumCloseIDs: 14
 -- out/evalalpha --
 Errors: