SIL Type: add Type.aggregateIsOrContains

Author: eeckstein

SwiftCompilerSources/Sources/SIL/Type.swift

@@ -154,6 +154,29 @@ public struct Type : CustomStringConvertible, NoReflectionChildren {
     return idx >= 0 ? idx : nil
   }
 
+  /// Returns true if this is a struct, enum or tuple and `otherType` is contained in this type - or is the same type.
+  public func aggregateIsOrContains(_ otherType: Type, in function: Function) -> Bool {
+    if self == otherType {
+      return true
+    }
+    if isStruct {
+      guard let fields = getNominalFields(in: function) else {
+        return true
+      }
+      return fields.contains { $0.aggregateIsOrContains(otherType, in: function) }
+    }
+    if isTuple {
+      return tupleElements.contains { $0.aggregateIsOrContains(otherType, in: function) }
+    }
+    if isEnum {
+      guard let cases = getEnumCases(in: function) else {
+        return true
+      }
+      return cases.contains { $0.payload?.aggregateIsOrContains(otherType, in: function) ?? false }
+    }
+    return false
+  }
+
 // compiling bridged.getFunctionTypeWithNoEscape crashes the 5.10 Windows compiler
 #if !os(Windows)
   // TODO: https://github.com/apple/swift/issues/73253