diff --git a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/FirOperation.kt b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/FirOperation.kt
index 86bf7f0073e..75c25a984d2 100644
--- a/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/FirOperation.kt
+++ b/compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/FirOperation.kt
@@ -43,5 +43,7 @@ enum class FirOperation(val operator: String = "???") {
         )
 
         val COMPARISONS: Set<FirOperation> = EnumSet.of(LT, GT, LT_EQ, GT_EQ)
+
+        val TYPES: Set<FirOperation> = EnumSet.of(IS, NOT_IS, AS, SAFE_AS)
     }
 }
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