Avoid object's interpretation with nullable type

#KT-56215 Fixed

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

@@ -28259,6 +28259,12 @@ public class FirBlackBoxCodegenTestGenerated extends AbstractFirBlackBoxCodegenT
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Test
         @TestMetadata("referenceNameFromStaticInDifferentModule.kt")
         public void testReferenceNameFromStaticInDifferentModule() throws Exception {

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/InstructionsUnfolder.kt

@@ -256,11 +256,11 @@ private fun unfoldSetField(expression: IrSetField, callStack: CallStack) {
 }
 
 private fun unfoldGetValue(expression: IrGetValue, environment: IrInterpreterEnvironment) {
-    if (expression.isAccessToObject()) {
+    if (expression.isAccessToNotNullableObject()) {
         // used to evaluate constants inside object
         // TODO is this correct behaviour?
         val irGetObject = expression.type.classOrNull?.owner!!.createGetObject()
-        return unfoldGetObjectValue(irGetObject, environment)
+        return unfoldGetObjectValue(irGetObject, environment) // if object already exists, it will be taken from `mapOfObjects`
     }
     environment.callStack.pushState(environment.callStack.loadState(expression.symbol))
 }

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/Utils.kt

@@ -294,10 +294,10 @@ internal fun IrClass.getSingleAbstractMethod(): IrFunction {
     return declarations.filterIsInstance<IrSimpleFunction>().single { it.modality == Modality.ABSTRACT }
 }
 
-internal fun IrGetValue.isAccessToObject(): Boolean {
+internal fun IrGetValue.isAccessToNotNullableObject(): Boolean {
     val owner = this.symbol.owner
     val expectedClass = this.type.classOrNull?.owner
-    if (expectedClass == null || !expectedClass.isObject) return false
+    if (expectedClass == null || !expectedClass.isObject || this.type.isNullable()) return false
     return owner.origin == IrDeclarationOrigin.INSTANCE_RECEIVER || owner.name.asString() == "<this>"
 }
 

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/checker/IrCompileTimeChecker.kt

@@ -11,7 +11,7 @@ import org.jetbrains.kotlin.ir.declarations.*
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.interpreter.accessesTopLevelOrObjectField
 import org.jetbrains.kotlin.ir.interpreter.fqName
-import org.jetbrains.kotlin.ir.interpreter.isAccessToObject
+import org.jetbrains.kotlin.ir.interpreter.isAccessToNotNullableObject
 import org.jetbrains.kotlin.ir.types.*
 import org.jetbrains.kotlin.ir.util.constructors
 import org.jetbrains.kotlin.ir.util.statements
@@ -160,7 +160,7 @@ class IrCompileTimeChecker(
     }
 
     override fun visitGetValue(expression: IrGetValue, data: Nothing?): Boolean {
-        return visitedStack.contains(expression.symbol.owner.parent) || expression.isAccessToObject()
+        return visitedStack.contains(expression.symbol.owner.parent) || expression.isAccessToNotNullableObject()
     }
 
     override fun visitSetValue(expression: IrSetValue, data: Nothing?): Boolean {

compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt

@@ -0,0 +1,22 @@
+object ObjectWithExtension
+
+fun ObjectWithExtension?.nullableExtensionFun(): String =
+    if(this == null)
+        "Null"
+    else
+        "Not null"
+
+fun ObjectWithExtension.extensionFun(): String =
+    if(this == null)
+        "Null" // unreachable branch, will be optimized by interpreter
+    else
+        "Not null"
+
+fun box(): String {
+    val nullObjectWithExtension: ObjectWithExtension? = null
+    if ("${nullObjectWithExtension.nullableExtensionFun()}" != "Null") return "Fail 1"
+    if ("${ObjectWithExtension.nullableExtensionFun()}" != "Not null") return "Fail 2"
+
+    if ("${ObjectWithExtension.extensionFun()}" != "Not null") return "Fail 3"
+    return "OK"
+}

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

@@ -27149,6 +27149,12 @@ public class BlackBoxCodegenTestGenerated extends AbstractBlackBoxCodegenTest {
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Nested
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")

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

@@ -28259,6 +28259,12 @@ public class IrBlackBoxCodegenTestGenerated extends AbstractIrBlackBoxCodegenTes
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Test
         @TestMetadata("referenceNameFromStaticInDifferentModule.kt")
         public void testReferenceNameFromStaticInDifferentModule() throws Exception {

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

@@ -22887,6 +22887,11 @@ public class LightAnalysisModeTestGenerated extends AbstractLightAnalysisModeTes
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)

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

@@ -20977,6 +20977,12 @@ public class JsCodegenBoxTestGenerated extends AbstractJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Nested
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/fir/FirJsCodegenBoxTestGenerated.java

@@ -20995,6 +20995,12 @@ public class FirJsCodegenBoxTestGenerated extends AbstractFirJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Nested
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")

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

@@ -20995,6 +20995,12 @@ public class IrJsCodegenBoxTestGenerated extends AbstractIrJsCodegenBoxTest {
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Nested
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")

js/js.tests/tests-gen/org/jetbrains/kotlin/js/test/ir/IrJsES6CodegenBoxTestGenerated.java

@@ -20995,6 +20995,12 @@ public class IrJsES6CodegenBoxTestGenerated extends AbstractIrJsES6CodegenBoxTes
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @Test
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @Nested
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/K2NativeCodegenBoxTestGenerated.java

@@ -23954,6 +23954,12 @@ public class K2NativeCodegenBoxTestGenerated extends AbstractNativeCodegenBoxTes
                 runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
             }
 
+            @Test
+            @TestMetadata("kt56215.kt")
+            public void testKt56215() throws Exception {
+                runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+            }
+
             @Nested
             @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
             @TestDataPath("$PROJECT_ROOT")

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/NativeCodegenBoxTestGenerated.java

@@ -23720,6 +23720,12 @@ public class NativeCodegenBoxTestGenerated extends AbstractNativeCodegenBoxTest
                 runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
             }
 
+            @Test
+            @TestMetadata("kt56215.kt")
+            public void testKt56215() throws Exception {
+                runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+            }
+
             @Nested
             @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
             @TestDataPath("$PROJECT_ROOT")

wasm/wasm.tests/tests-gen/org/jetbrains/kotlin/wasm/test/IrCodegenBoxWasmTestGenerated.java

@@ -18635,6 +18635,11 @@ public class IrCodegenBoxWasmTestGenerated extends AbstractIrCodegenBoxWasmTest
             runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt55912.kt");
         }
 
+        @TestMetadata("kt56215.kt")
+        public void testKt56215() throws Exception {
+            runTest("compiler/testData/codegen/box/involvesIrInterpreter/kt56215.kt");
+        }
+
         @TestMetadata("compiler/testData/codegen/box/involvesIrInterpreter/dumpIrAndCheck")
         @TestDataPath("$PROJECT_ROOT")
         @RunWith(JUnit3RunnerWithInners.class)