diff --git a/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.fir.kt b/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.fir.kt
deleted file mode 100644
index 03781e5adfa..00000000000
--- a/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.fir.kt
+++ /dev/null
@@ -1,7 +0,0 @@
-interface G<T> {
-    fun foo()
-    val bar: Int
-}
-
-fun <!WRONG_NUMBER_OF_TYPE_ARGUMENTS!>G<!>.foo() {}
-val <!WRONG_NUMBER_OF_TYPE_ARGUMENTS!>G<!>.bar: Int get() = 42
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.kt b/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.kt
index 03781e5adfa..79f828acfd1 100644
--- a/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.kt
+++ b/compiler/testData/diagnostics/tests/redeclarations/shadowedExtension/extensionOnErrorType.kt
@@ -1,3 +1,5 @@
+// FIR_IDENTICAL
+
 interface G<T> {
     fun foo()
     val bar: Int
diff --git a/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.fir.kt b/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.fir.kt
deleted file mode 100644
index d8ef905f937..00000000000
--- a/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.fir.kt
+++ /dev/null
@@ -1,3 +0,0 @@
-class Class1<T : Class2<Class1<<!UNRESOLVED_REFERENCE!>X<!>>>>
-
-class Class2<T : Class1<Class2<<!UNRESOLVED_REFERENCE!>X<!>>>>
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.kt b/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.kt
index d8ef905f937..7065ae0cf1a 100644
--- a/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.kt
+++ b/compiler/testData/diagnostics/tests/resolve/CycleInTypeArgs.kt
@@ -1,3 +1,5 @@
+// FIR_IDENTICAL
+
 class Class1<T : Class2<Class1<<!UNRESOLVED_REFERENCE!>X<!>>>>
 
 class Class2<T : Class1<Class2<<!UNRESOLVED_REFERENCE!>X<!>>>>
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/subtyping/kt304.fir.kt b/compiler/testData/diagnostics/tests/subtyping/kt304.fir.kt
deleted file mode 100644
index 95b34f3a56a..00000000000
--- a/compiler/testData/diagnostics/tests/subtyping/kt304.fir.kt
+++ /dev/null
@@ -1,7 +0,0 @@
-//KT-304: Resolve supertype reference to class anyway
-
-open class Foo() : <!WRONG_NUMBER_OF_TYPE_ARGUMENTS!>Bar<!>() {
-}
-
-open class Bar<T>() {
-}
\ No newline at end of file
diff --git a/compiler/testData/diagnostics/tests/subtyping/kt304.kt b/compiler/testData/diagnostics/tests/subtyping/kt304.kt
index 95b34f3a56a..f8eb56c0730 100644
--- a/compiler/testData/diagnostics/tests/subtyping/kt304.kt
+++ b/compiler/testData/diagnostics/tests/subtyping/kt304.kt
@@ -1,3 +1,5 @@
+// FIR_IDENTICAL
+
 //KT-304: Resolve supertype reference to class anyway
 
 open class Foo() : <!WRONG_NUMBER_OF_TYPE_ARGUMENTS!>Bar<!>() {