JVM IR: do not optimize casts for primitives in TypeOperatorLowering

#KT-48659 Fixed

compiler/fir/fir2ir/tests-gen/org/jetbrains/kotlin/test/runners/codegen/FirBlackBoxCodegenTestGenerated.java

@@ -28824,6 +28824,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/primitiveTypes/kt46864_long.kt");
         }
 
+        @Test
+        @TestMetadata("kt48659_identityEqualsWithCastToAny.kt")
+        public void testKt48659_identityEqualsWithCastToAny() throws Exception {
+            runTest("compiler/testData/codegen/box/primitiveTypes/kt48659_identityEqualsWithCastToAny.kt");
+        }
+
         @Test
         @TestMetadata("kt518.kt")
         public void testKt518() throws Exception {

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/TypeOperatorLowering.kt

@@ -100,7 +100,8 @@ private class TypeOperatorLowering(private val context: JvmBackendContext) : Fil
                     )
                 }
             }
-        argument.type.isSubtypeOfClass(type.erasedUpperBound.symbol) ->
+        // Do not optimize casts for values of primitive types because it can affect their identity and thus change behavior.
+        !argument.type.isPrimitiveType() && argument.type.isSubtypeOfClass(type.erasedUpperBound.symbol) ->
             argument
         else ->
             builder.irAs(argument, type)

compiler/testData/codegen/box/primitiveTypes/kt48659_identityEqualsWithCastToAny.kt

@@ -0,0 +1,26 @@
+// TARGET_BACKEND: JVM
+
+fun int(a: Int, b: Int): Boolean = (a as Any) === (b as Any)
+fun short(a: Short, b: Short): Boolean = (a as Any) === (b as Any)
+fun char(a: Char, b: Char): Boolean = (a as Any) === (b as Any)
+fun long(a: Long, b: Long): Boolean = (a as Any) === (b as Any)
+fun float(a: Float, b: Float): Boolean = (a as Any) === (b as Any)
+fun double(a: Double, b: Double): Boolean = (a as Any) === (b as Any)
+
+fun byte(a: Byte, b: Byte): Boolean = (a as Any) === (b as Any)
+fun boolean(a: Boolean, b: Boolean): Boolean = (a as Any) === (b as Any)
+
+fun box(): String {
+    if (int(2021, 2021)) return "Fail int"
+    if (short(32042, 32042)) return "Fail short"
+    if (char(4242.toChar(), 4242.toChar())) return "Fail char"
+    if (long(4242424242L, 4242424242L)) return "Fail long"
+    if (float(3.14f, 3.14f)) return "Fail float"
+    if (double(2.72, 2.72)) return "Fail double"
+
+    // All byte and boolean values are cached in java.lang.Byte/Boolean.valueOf
+    if (!byte(127, 127)) return "Fail byte"
+    if (!boolean(true, true)) return "Fail boolean"
+
+    return "OK"
+}

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/BlackBoxCodegenTestGenerated.java

@@ -28692,6 +28692,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             runTest("compiler/testData/codegen/box/primitiveTypes/kt46864_long.kt");
         }
 
+        @Test
+        @TestMetadata("kt48659_identityEqualsWithCastToAny.kt")
+        public void testKt48659_identityEqualsWithCastToAny() throws Exception {
+            runTest("compiler/testData/codegen/box/primitiveTypes/kt48659_identityEqualsWithCastToAny.kt");
+        }
+
         @Test
         @TestMetadata("kt518.kt")
         public void testKt518() throws Exception {

compiler/tests-common-new/tests-gen/org/jetbrains/kotlin/test/runners/codegen/IrBlackBoxCodegenTestGenerated.java

@@ -28824,6 +28824,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/primitiveTypes/kt46864_long.kt");
         }
 
+        @Test
+        @TestMetadata("kt48659_identityEqualsWithCastToAny.kt")
+        public void testKt48659_identityEqualsWithCastToAny() throws Exception {
+            runTest("compiler/testData/codegen/box/primitiveTypes/kt48659_identityEqualsWithCastToAny.kt");
+        }
+
         @Test
         @TestMetadata("kt518.kt")
         public void testKt518() throws Exception {

compiler/tests-gen/org/jetbrains/kotlin/codegen/LightAnalysisModeTestGenerated.java

@@ -24375,6 +24375,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             runTest("compiler/testData/codegen/box/primitiveTypes/kt46864_long.kt");
         }
 
+        @TestMetadata("kt48659_identityEqualsWithCastToAny.kt")
+        public void testKt48659_identityEqualsWithCastToAny() throws Exception {
+            runTest("compiler/testData/codegen/box/primitiveTypes/kt48659_identityEqualsWithCastToAny.kt");
+        }
+
         @TestMetadata("kt518.kt")
         public void testKt518() throws Exception {
             runTest("compiler/testData/codegen/box/primitiveTypes/kt518.kt");