JVM_IR fix cast to not-null type

We can't rely on argument type nullability here, because it still can
hold an uninitialized value on JVM.

KT-50577 KT-35272 KT-27427

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/JsCodegenBoxTestGenerated.java

@@ -3371,6 +3371,12 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/casts/kt48927_privateMethodOnDerivedCastToBase.kt");
         }
 
+        @Test
+        @TestMetadata("kt50577.kt")
+        public void testKt50577() throws Exception {
+            runTest("compiler/testData/codegen/box/casts/kt50577.kt");
+        }
+
         @Test
         @TestMetadata("lambdaToUnitCast.kt")
         public void testLambdaToUnitCast() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrJsCodegenBoxTestGenerated.java

@@ -3413,6 +3413,12 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/casts/kt48927_privateMethodOnDerivedCastToBase.kt");
         }
 
+        @Test
+        @TestMetadata("kt50577.kt")
+        public void testKt50577() throws Exception {
+            runTest("compiler/testData/codegen/box/casts/kt50577.kt");
+        }
+
         @Test
         @TestMetadata("lambdaToUnitCast.kt")
         public void testLambdaToUnitCast() throws Exception {

js/js.tests/tests-gen/org/jetbrains/kotlin/js/testOld/wasm/semantics/IrCodegenBoxWasmTestGenerated.java

@@ -3016,6 +3016,11 @@ public class IrCodegenBoxWasmTestGenerated extends AbstractIrCodegenBoxWasmTest
             runTest("compiler/testData/codegen/box/casts/kt48927_privateMethodOnDerivedCastToBase.kt");
         }
 
+        @TestMetadata("kt50577.kt")
+        public void testKt50577() throws Exception {
+            runTest("compiler/testData/codegen/box/casts/kt50577.kt");
+        }
+
         @TestMetadata("lambdaToUnitCast.kt")
         public void testLambdaToUnitCast() throws Exception {
             runTest("compiler/testData/codegen/box/casts/lambdaToUnitCast.kt");