Ruby: Cache exprNodeReturnedFrom

Author: hvitved

ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowDispatch.qll

@@ -463,18 +463,7 @@ predicate mayBenefitFromCallContext(DataFlowCall call, DataFlowCallable c) { non
  */
 DataFlowCallable viableImplInCallContext(DataFlowCall call, DataFlowCall ctx) { none() }
 
-/**
- * Holds if `e` is an `ExprNode` that may be returned by a call to `c`.
- */
-predicate exprNodeReturnedFrom(DataFlow::ExprNode e, Callable c) {
-  exists(ReturningNode r |
-    nodeGetEnclosingCallable(r).asCallable() = c and
-    (
-      r.(ExplicitReturnNode).getReturningNode().getReturnedValueNode() = e.asExpr() or
-      r.(ExprReturnNode) = e
-    )
-  )
-}
+predicate exprNodeReturnedFrom = exprNodeReturnedFromCached/2;
 
 /** A parameter position. */
 class ParameterPosition extends TParameterPosition {

ruby/ql/lib/codeql/ruby/dataflow/internal/DataFlowPrivate.qll

@@ -297,6 +297,20 @@ private module Cached {
     TKnownArrayElementContent(int i) { i in [0 .. 10] } or
     TUnknownArrayElementContent() or
     TAnyArrayElementContent()
+
+  /**
+   * Holds if `e` is an `ExprNode` that may be returned by a call to `c`.
+   */
+  cached
+  predicate exprNodeReturnedFromCached(ExprNode e, Callable c) {
+    exists(ReturningNode r |
+      nodeGetEnclosingCallable(r).asCallable() = c and
+      (
+        r.(ExplicitReturnNode).getReturningNode().getReturnedValueNode() = e.asExpr() or
+        r.(ExprReturnNode) = e
+      )
+    )
+  }
 }
 
 class TArrayElementContent = TKnownArrayElementContent or TUnknownArrayElementContent;