JVM_IR: set ConstantValue on static final primitive fields

2019-04-11 12:44:38 +02:00
parent 14485c0e33
commit b23f2a4dbb
20 changed files with 40 additions and 29 deletions
@@ -66,8 +66,8 @@ val jvmPhases = namedIrFilePhase(
            jvmLateinitPhase then

            moveCompanionObjectFieldsPhase then
-            constPhase then
            propertyReferencePhase then
+            constPhase then
            propertiesToFieldsPhase then
            propertiesPhase then
            renameFieldsPhase then
@@ -18,17 +18,17 @@ package org.jetbrains.kotlin.backend.jvm.codegen

 import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
 import org.jetbrains.kotlin.backend.jvm.JvmLoweredDeclarationOrigin
+import org.jetbrains.kotlin.backend.jvm.lower.constantValue
 import org.jetbrains.kotlin.codegen.*
 import org.jetbrains.kotlin.codegen.binding.CodegenBinding
 import org.jetbrains.kotlin.codegen.inline.DefaultSourceMapper
 import org.jetbrains.kotlin.codegen.inline.SourceMapper
 import org.jetbrains.kotlin.codegen.serialization.JvmSerializationBindings
 import org.jetbrains.kotlin.codegen.serialization.JvmSerializerExtension
-import org.jetbrains.kotlin.descriptors.ClassDescriptor
-import org.jetbrains.kotlin.descriptors.DeclarationDescriptor
-import org.jetbrains.kotlin.descriptors.Modality
-import org.jetbrains.kotlin.descriptors.Visibility
+import org.jetbrains.kotlin.config.LanguageFeature
+import org.jetbrains.kotlin.descriptors.*
 import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.expressions.IrConst
 import org.jetbrains.kotlin.ir.util.*
 import org.jetbrains.kotlin.load.java.JvmAbi
 import org.jetbrains.kotlin.load.kotlin.header.KotlinClassHeader
@@ -36,6 +36,7 @@ import org.jetbrains.kotlin.name.SpecialNames
 import org.jetbrains.kotlin.psi.KtElement
 import org.jetbrains.kotlin.resolve.DescriptorUtils
 import org.jetbrains.kotlin.resolve.DescriptorUtils.isTopLevelDeclaration
+import org.jetbrains.kotlin.resolve.jvm.AsmTypes
 import org.jetbrains.kotlin.resolve.jvm.diagnostics.JvmDeclarationOrigin
 import org.jetbrains.kotlin.resolve.jvm.diagnostics.OtherOrigin
 import org.jetbrains.kotlin.resolve.source.getPsi
@@ -218,9 +219,13 @@ open class ClassCodegen protected constructor(
        val fieldType = typeMapper.mapType(field.descriptor)
        val fieldSignature = typeMapper.mapFieldSignature(field.descriptor.type, field.descriptor)
        val fieldName = field.descriptor.name.asString()
+        // The ConstantValue attribute makes the initializer part of the ABI, which is why since 1.4
+        // it is no longer set unless the property is explicitly `const`.
+        val implicitConst = !state.languageVersionSettings.supportsFeature(LanguageFeature.NoConstantValueAttributeForNonConstVals) &&
+                (AsmUtil.isPrimitive(fieldType) || fieldType == AsmTypes.JAVA_STRING_TYPE)
        val fv = visitor.newField(
            field.OtherOrigin, field.flags, fieldName, fieldType.descriptor,
-            fieldSignature, null/*TODO support default values*/
+            fieldSignature, field.constantValue(implicitConst)?.value
        )

        AnnotationCodegen(this, state, fv::visitAnnotation).genAnnotations(field, fieldType)
@@ -10,6 +10,7 @@ import org.jetbrains.kotlin.backend.jvm.JvmLoweredDeclarationOrigin
 import org.jetbrains.kotlin.backend.jvm.intrinsics.JavaClassProperty
 import org.jetbrains.kotlin.backend.jvm.intrinsics.Not
 import org.jetbrains.kotlin.backend.jvm.lower.CrIrType
+import org.jetbrains.kotlin.backend.jvm.lower.constantValue
 import org.jetbrains.kotlin.builtins.KotlinBuiltIns
 import org.jetbrains.kotlin.codegen.*
 import org.jetbrains.kotlin.codegen.AsmUtil.*
@@ -421,6 +422,14 @@ class ExpressionCodegen(
    }

    override fun visitFieldAccess(expression: IrFieldAccessExpression, data: BlockInfo): PromisedValue {
+        expression.symbol.owner.constantValue()?.let {
+            // Handling const reads before codegen is important for constant folding.
+            assert(expression is IrSetField) { "read of const val ${expression.symbol.owner.name} not inlined by ConstLowering" }
+            // This can only be the field's initializer; JVM implementations are required
+            // to generate those for ConstantValue-marked fields automatically, so this is redundant.
+            return voidValue.coerce(expression.asmType)
+        }
+
        val realDescriptor = DescriptorUtils.unwrapFakeOverride(expression.descriptor)
        val fieldType = typeMapper.mapType(realDescriptor.original.type)
        val ownerType = typeMapper.mapImplementationOwner(expression.descriptor).internalName
@@ -8,11 +8,14 @@ package org.jetbrains.kotlin.backend.jvm.lower
 import org.jetbrains.kotlin.backend.common.CommonBackendContext
 import org.jetbrains.kotlin.backend.common.FileLoweringPass
 import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
+import org.jetbrains.kotlin.ir.declarations.IrDeclarationOrigin
+import org.jetbrains.kotlin.ir.declarations.IrField
 import org.jetbrains.kotlin.ir.declarations.IrFile
 import org.jetbrains.kotlin.ir.declarations.IrSimpleFunction
 import org.jetbrains.kotlin.ir.expressions.IrCall
 import org.jetbrains.kotlin.ir.expressions.IrConst
 import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.IrGetField
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid

@@ -22,19 +25,27 @@ internal val constPhase = makeIrFilePhase(
    description = "Substitute calls to const properties with constant values"
 )

+fun IrField.constantValue(implicitConst: Boolean = false): IrConst<*>? {
+    // javac always inlines reads of static final fields, so do that for ones imported from Java.
+    // Kotlin fields are only inlined if explicitly `const` to avoid making the values part of the ABI.
+    val inline = correspondingPropertySymbol?.owner?.isConst == true ||
+            (isStatic && isFinal && (origin == IrDeclarationOrigin.IR_EXTERNAL_JAVA_DECLARATION_STUB || implicitConst))
+    return if (inline) initializer?.expression as? IrConst<*> else null
+}
+
 class ConstLowering(val context: CommonBackendContext) : IrElementTransformerVoid(), FileLoweringPass {
    override fun lower(irFile: IrFile) {
        irFile.transformChildrenVoid(this)
    }

    override fun visitCall(expression: IrCall): IrExpression {
-        val irSimpleFunction = (expression.symbol.owner as? IrSimpleFunction) ?: return super.visitCall(expression)
-        val irProperty = irSimpleFunction.correspondingProperty ?: return super.visitCall(expression)
-
-        if (irProperty.isConst) {
-            (irProperty.backingField!!.initializer!!.expression as IrConst<*>).let { return it }
-        }
-
-        return super.visitCall(expression)
+        val function = (expression.symbol.owner as? IrSimpleFunction) ?: return super.visitCall(expression)
+        val property = function.correspondingPropertySymbol?.owner ?: return super.visitCall(expression)
+        if (function != property.getter)
+            return super.visitCall(expression)
+        return property.backingField?.constantValue() ?: super.visitCall(expression)
    }
+
+    override fun visitGetField(expression: IrGetField): IrExpression =
+        expression.symbol.owner.constantValue() ?: super.visitGetField(expression)
 }
@@ -101,6 +101,7 @@ private class MoveCompanionObjectFieldsLowering(val context: CommonBackendContex
        val newField = createStaticBackingField(oldField, propertyParent, fieldParent)

        irProperty.backingField = newField
+        newField.correspondingPropertySymbol = irProperty.symbol

        fieldReplacementMap[oldField.symbol] = newField.symbol

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM

 // WITH_RUNTIME
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // WITH_REFLECT
 // FILE: 1.kt
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // IGNORE_LIGHT_ANALYSIS
 // WITH_RUNTIME
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 object A {
    private const val a = "$"
    private const val b = "1234$a"
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // FILE: JClass.java

 import org.jetbrains.annotations.NotNull;
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // FILE: first/Foo.java

 package first;
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // FILE: JClass.java

 import org.jetbrains.annotations.NotNull;
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
@file:JvmName("ABC")
 package test;

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 package test

 annotation class AString(val value: String)
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 package test

 class KotlinClass {
@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: A.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: A.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: A.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // TARGET_BACKEND: JVM
 // FILE: A.kt

@@ -1,4 +1,3 @@
-// IGNORE_BACKEND: JVM_IR
 // IGNORE_BACKEND: NATIVE
 // WITH_RUNTIME