Skip property accessors for constants

- Inline protected constants from Java at use sites
 - Do not create accessors for private constants in Kotlin

 #KT-11734 In Progress

compiler/backend/src/org/jetbrains/kotlin/codegen/ExpressionCodegen.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -50,6 +50,10 @@ import org.jetbrains.kotlin.codegen.state.GenerationState;
 import org.jetbrains.kotlin.codegen.state.KotlinTypeMapper;
 import org.jetbrains.kotlin.codegen.when.SwitchCodegen;
 import org.jetbrains.kotlin.codegen.when.SwitchCodegenUtil;
+import org.jetbrains.kotlin.config.CommonConfigurationKeys;
+import org.jetbrains.kotlin.config.LanguageFeature;
+import org.jetbrains.kotlin.config.LanguageVersionSettings;
+import org.jetbrains.kotlin.config.LanguageVersionSettingsImpl;
 import org.jetbrains.kotlin.coroutines.CoroutineUtilKt;
 import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor;
@@ -2603,9 +2607,16 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
         boolean skipPropertyAccessors;
 
         PropertyDescriptor originalPropertyDescriptor = DescriptorUtils.unwrapFakeOverride(propertyDescriptor);
+        LanguageVersionSettings languageVersionSettings = state.getConfiguration().get(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS);
+        if (languageVersionSettings == null) {
+            languageVersionSettings = LanguageVersionSettingsImpl.DEFAULT;
+        }
+
         if (fieldAccessorKind != FieldAccessorKind.NORMAL) {
             int flags = AsmUtil.getVisibilityForBackingField(propertyDescriptor, isDelegatedProperty);
-            skipPropertyAccessors = (flags & ACC_PRIVATE) == 0 || skipAccessorsForPrivateFieldInOuterClass;
+            boolean isInlinedConst = propertyDescriptor.isConst() && languageVersionSettings.supportsFeature(LanguageFeature.InlineConstVals);
+            skipPropertyAccessors = isInlinedConst || (flags & ACC_PRIVATE) == 0 || skipAccessorsForPrivateFieldInOuterClass;
+
             if (!skipPropertyAccessors) {
                 //noinspection ConstantConditions
                 propertyDescriptor = (PropertyDescriptor) backingFieldContext.getAccessor(
@@ -2624,7 +2635,7 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
         }
 
         if (!skipPropertyAccessors) {
-            if (!couldUseDirectAccessToProperty(propertyDescriptor, true, isDelegatedProperty, context)) {
+            if (!couldUseDirectAccessToProperty(propertyDescriptor, true, isDelegatedProperty, context, languageVersionSettings)) {
                 propertyDescriptor = context.getAccessorForSuperCallIfNeeded(propertyDescriptor, superCallTarget);
 
                 propertyDescriptor = context.accessibleDescriptor(propertyDescriptor, superCallTarget);
@@ -2638,7 +2649,7 @@ public class ExpressionCodegen extends KtVisitor<StackValue, StackValue> impleme
             if (propertyDescriptor.isVar()) {
                 PropertySetterDescriptor setter = propertyDescriptor.getSetter();
                 if (setter != null &&
-                    !couldUseDirectAccessToProperty(propertyDescriptor, false, isDelegatedProperty, context) &&
+                    !couldUseDirectAccessToProperty(propertyDescriptor, false, isDelegatedProperty, context, languageVersionSettings) &&
                     !isConstOrHasJvmFieldAnnotation(propertyDescriptor)) {
                     callableSetter = typeMapper.mapToCallableMethod(setter, isSuper);
                 }

compiler/backend/src/org/jetbrains/kotlin/codegen/ImplementationBodyCodegen.java

@@ -37,6 +37,9 @@ import org.jetbrains.kotlin.codegen.signature.BothSignatureWriter;
 import org.jetbrains.kotlin.codegen.signature.JvmSignatureWriter;
 import org.jetbrains.kotlin.codegen.state.GenerationState;
 import org.jetbrains.kotlin.codegen.state.KotlinTypeMapper;
+import org.jetbrains.kotlin.config.CommonConfigurationKeys;
+import org.jetbrains.kotlin.config.LanguageVersionSettings;
+import org.jetbrains.kotlin.config.LanguageVersionSettingsImpl;
 import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.incremental.components.NoLookupLocation;
 import org.jetbrains.kotlin.lexer.KtTokens;
@@ -646,7 +649,12 @@ public class ImplementationBodyCodegen extends ClassBodyCodegen {
 
         private Type genPropertyOnStack(InstructionAdapter iv, MethodContext context, @NotNull PropertyDescriptor propertyDescriptor, int index) {
             iv.load(index, classAsmType);
-            if (couldUseDirectAccessToProperty(propertyDescriptor, /* forGetter = */ true, /* isDelegated = */ false, context)) {
+            LanguageVersionSettings settings = state.getConfiguration().get(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS);
+            if (settings == null) {
+                settings = LanguageVersionSettingsImpl.DEFAULT;
+            }
+            if (couldUseDirectAccessToProperty(propertyDescriptor, /* forGetter = */ true,
+                                               /* isDelegated = */ false, context, settings)) {
                 Type type = typeMapper.mapType(propertyDescriptor.getType());
                 String fieldName = ((FieldOwnerContext) context.getParentContext()).getFieldName(propertyDescriptor, false);
                 iv.getfield(classAsmType.getInternalName(), fieldName, type.getDescriptor());

compiler/backend/src/org/jetbrains/kotlin/codegen/JvmCodegenUtil.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,6 +30,8 @@ import org.jetbrains.kotlin.codegen.context.MethodContext;
 import org.jetbrains.kotlin.codegen.context.RootContext;
 import org.jetbrains.kotlin.codegen.state.GenerationState;
 import org.jetbrains.kotlin.codegen.state.KotlinTypeMapper;
+import org.jetbrains.kotlin.config.LanguageFeature;
+import org.jetbrains.kotlin.config.LanguageVersionSettings;
 import org.jetbrains.kotlin.descriptors.*;
 import org.jetbrains.kotlin.descriptors.impl.LocalVariableDescriptor;
 import org.jetbrains.kotlin.load.java.descriptors.JavaPropertyDescriptor;
@@ -182,8 +184,11 @@ public class JvmCodegenUtil {
             @NotNull PropertyDescriptor property,
             boolean forGetter,
             boolean isDelegated,
-            @NotNull MethodContext contextBeforeInline
+            @NotNull MethodContext contextBeforeInline,
+            @NotNull LanguageVersionSettings languageVersionSettings
     ) {
+        if (languageVersionSettings.supportsFeature(LanguageFeature.InlineConstVals) && property.isConst()) return true;
+
         if (KotlinTypeMapper.isAccessor(property)) return false;
 
         CodegenContext context = contextBeforeInline.getFirstCrossInlineOrNonInlineContext();

compiler/testData/codegen/bytecodeText/constProperty/accessorsForPrivateConstants.kt

@@ -0,0 +1,17 @@
+// LANGUAGE_VERSION: 1.0
+// FILE: Foo.kt
+
+private const val OUTER_PRIVATE = 20
+
+class Foo {
+    companion object {
+        private const val LOCAL_PRIVATE = 20
+    }
+
+    fun foo() {
+        LOCAL_PRIVATE
+        OUTER_PRIVATE
+    }
+}
+
+// 2 INVOKESTATIC

compiler/testData/codegen/bytecodeText/constProperty/noAccessorsForPrivateConstants.kt

@@ -0,0 +1,16 @@
+// FILE: Foo.kt
+
+private const val OUTER_PRIVATE = 20
+
+class Foo {
+    companion object {
+        private const val LOCAL_PRIVATE = 20
+    }
+
+    fun foo() {
+        LOCAL_PRIVATE
+        OUTER_PRIVATE
+    }
+}
+
+// 0 INVOKESTATIC

compiler/testData/codegen/bytecodeText/inlineProtectedJavaConstantFromOtherPackage.kt

@@ -0,0 +1,22 @@
+// FILE: first/Foo.java
+
+package first;
+
+public class Foo {
+    protected static final int FOO = 42;
+}
+
+// FILE: bar.kt
+
+package second
+
+import first.Foo
+
+class Bar : Foo() {
+    fun bar() = FOO
+}
+
+// @second/BarKt.class
+// 0 INVOKESTATIC
+// 0 GETSTATIC
+// 1 BIPUSH 42

compiler/testData/codegen/bytecodeText/noInlineJavaProtectedConstants.kt

@@ -0,0 +1,23 @@
+// LANGUAGE_VERSION: 1.0
+// FILE: first/Foo.java
+
+package first;
+
+public class Foo {
+    protected static final int FOO = 42;
+}
+
+// FILE: bar.kt
+
+package second
+
+import first.Foo
+
+class Bar : Foo() {
+    fun bar() = FOO
+}
+
+// @second/BarKt.class
+// 1 INVOKESTATIC
+// 0 GETSTATIC
+// 1 BIPUSH 42

compiler/tests/org/jetbrains/kotlin/codegen/BytecodeTextTestGenerated.java

@@ -138,6 +138,12 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
         doTest(fileName);
     }
 
+    @TestMetadata("inlineProtectedJavaConstantFromOtherPackage.kt")
+    public void testInlineProtectedJavaConstantFromOtherPackage() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/inlineProtectedJavaConstantFromOtherPackage.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("intConstantNotNull.kt")
     public void testIntConstantNotNull() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/intConstantNotNull.kt");
@@ -270,6 +276,12 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
         doTest(fileName);
     }
 
+    @TestMetadata("noInlineJavaProtectedConstants.kt")
+    public void testNoInlineJavaProtectedConstants() throws Exception {
+        String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/noInlineJavaProtectedConstants.kt");
+        doTest(fileName);
+    }
+
     @TestMetadata("noNumberCheckCast.kt")
     public void testNoNumberCheckCast() throws Exception {
         String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/noNumberCheckCast.kt");
@@ -712,10 +724,22 @@ public class BytecodeTextTestGenerated extends AbstractBytecodeTextTest {
     @TestDataPath("$PROJECT_ROOT")
     @RunWith(JUnit3RunnerWithInners.class)
     public static class ConstProperty extends AbstractBytecodeTextTest {
+        @TestMetadata("accessorsForPrivateConstants.kt")
+        public void testAccessorsForPrivateConstants() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/constProperty/accessorsForPrivateConstants.kt");
+            doTest(fileName);
+        }
+
         public void testAllFilesPresentInConstProperty() throws Exception {
             KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/testData/codegen/bytecodeText/constProperty"), Pattern.compile("^(.+)\\.kt$"), TargetBackend.ANY, true);
         }
 
+        @TestMetadata("noAccessorsForPrivateConstants.kt")
+        public void testNoAccessorsForPrivateConstants() throws Exception {
+            String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/constProperty/noAccessorsForPrivateConstants.kt");
+            doTest(fileName);
+        }
+
         @TestMetadata("noInline.kt")
         public void testNoInline() throws Exception {
             String fileName = KotlinTestUtils.navigationMetadata("compiler/testData/codegen/bytecodeText/constProperty/noInline.kt");

compiler/util/src/org/jetbrains/kotlin/config/LanguageVersionSettings.kt

@@ -34,6 +34,7 @@ enum class LanguageFeature(val sinceVersion: LanguageVersion?) {
     DslMarkersSupport(KOTLIN_1_1),
     UnderscoresInNumericLiterals(KOTLIN_1_1),
     DivisionByZeroInConstantExpressions(KOTLIN_1_1),
+    InlineConstVals(KOTLIN_1_1),
 
     // Experimental features
     MultiPlatformProjects(null),

idea/src/org/jetbrains/kotlin/idea/internal/KotlinBytecodeToolWindow.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -41,14 +41,12 @@ import org.jetbrains.kotlin.codegen.ClassBuilderFactories;
 import org.jetbrains.kotlin.codegen.CompilationErrorHandler;
 import org.jetbrains.kotlin.codegen.KotlinCodegenFacade;
 import org.jetbrains.kotlin.codegen.state.GenerationState;
-import org.jetbrains.kotlin.config.CommonConfigurationKeys;
-import org.jetbrains.kotlin.config.CompilerConfiguration;
-import org.jetbrains.kotlin.config.JVMConfigurationKeys;
-import org.jetbrains.kotlin.config.JvmTarget;
+import org.jetbrains.kotlin.config.*;
 import org.jetbrains.kotlin.diagnostics.Diagnostic;
 import org.jetbrains.kotlin.diagnostics.rendering.DefaultErrorMessages;
 import org.jetbrains.kotlin.idea.caches.resolve.ResolutionUtils;
 import org.jetbrains.kotlin.idea.debugger.DebuggerUtils;
+import org.jetbrains.kotlin.idea.project.PlatformKt;
 import org.jetbrains.kotlin.idea.resolve.ResolutionFacade;
 import org.jetbrains.kotlin.idea.util.InfinitePeriodicalTask;
 import org.jetbrains.kotlin.idea.util.LongRunningReadTask;
@@ -136,6 +134,9 @@ public class KotlinBytecodeToolWindow extends JPanel implements Disposable {
                 configuration.put(JVMConfigurationKeys.IR, true);
             }
 
+            LanguageVersionSettings languageVersionSettings = PlatformKt.getLanguageVersionSettings(ktFile);
+            configuration.put(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS, languageVersionSettings);
+
             return getBytecodeForFile(ktFile, configuration);
         }
 

idea/src/org/jetbrains/kotlin/idea/internal/KotlinDecompilerServiceImpl.kt

@@ -25,8 +25,10 @@ import org.jetbrains.java.decompiler.main.decompiler.BaseDecompiler
 import org.jetbrains.java.decompiler.main.extern.IBytecodeProvider
 import org.jetbrains.java.decompiler.main.extern.IFernflowerPreferences
 import org.jetbrains.java.decompiler.main.extern.IResultSaver
+import org.jetbrains.kotlin.config.CommonConfigurationKeys
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.idea.actions.canBeDecompiledToJava
+import org.jetbrains.kotlin.idea.project.languageVersionSettings
 import org.jetbrains.kotlin.psi.KtFile
 import java.io.File
 import java.util.jar.Manifest
@@ -72,7 +74,10 @@ class KotlinDecompilerServiceImpl : KotlinDecompilerService {
     }
 
     fun bytecodeMapForSourceFile(file: KtFile): Map<File, () -> ByteArray> {
-        val generationState = KotlinBytecodeToolWindow.compileSingleFile(file, CompilerConfiguration.EMPTY)
+        val configuration = CompilerConfiguration().apply {
+            put(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS, file.languageVersionSettings)
+        }
+        val generationState = KotlinBytecodeToolWindow.compileSingleFile(file, configuration)
 
         val bytecodeMap = hashMapOf<File, () -> ByteArray>()
         generationState.factory.asList().filter { FileUtilRt.extensionEquals(it.relativePath, "class") }.forEach {

idea/tests/org/jetbrains/kotlin/idea/internal/AbstractBytecodeToolWindowTest.kt

@@ -1,5 +1,5 @@
 /*
- * Copyright 2010-2015 JetBrains s.r.o.
+ * Copyright 2010-2016 JetBrains s.r.o.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -19,6 +19,7 @@ package org.jetbrains.kotlin.idea.internal
 import org.jetbrains.kotlin.config.CommonConfigurationKeys
 import org.jetbrains.kotlin.config.CompilerConfiguration
 import org.jetbrains.kotlin.idea.KotlinFileType
+import org.jetbrains.kotlin.idea.project.languageVersionSettings
 import org.jetbrains.kotlin.idea.test.KotlinLightCodeInsightFixtureTestCase
 import org.jetbrains.kotlin.idea.test.KotlinWithJdkAndRuntimeLightProjectDescriptor
 import org.jetbrains.kotlin.psi.KtFile
@@ -44,6 +45,9 @@ abstract class AbstractBytecodeToolWindowTest: KotlinLightCodeInsightFixtureTest
         if (InTextDirectivesUtils.getPrefixedBoolean(mainFileText, "// INLINE:") == false) {
             configuration.put(CommonConfigurationKeys.DISABLE_INLINE, true)
         }
+
+        configuration.put(CommonConfigurationKeys.LANGUAGE_VERSION_SETTINGS, file.languageVersionSettings)
+
         val bytecodes = KotlinBytecodeToolWindow.getBytecodeForFile(file, configuration)
         assert(bytecodes.contains("// ================")) {
             "The header \"// ================\" is missing.\n This means that there is an exception failed during compilation:\n$bytecodes"