[K/N] Run inline property accessors later to inline all cases including devirtualized

compiler/ir/backend.common/src/org/jetbrains/kotlin/backend/common/lower/optimizations/PropertyAccessorInlineLowering.kt

@@ -20,6 +20,7 @@ import org.jetbrains.kotlin.ir.expressions.impl.IrSetFieldImpl
 import org.jetbrains.kotlin.ir.util.deepCopyWithSymbols
 import org.jetbrains.kotlin.ir.util.isEffectivelyExternal
 import org.jetbrains.kotlin.backend.common.ir.isPure
+import org.jetbrains.kotlin.ir.types.isUnit
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
 import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
 
@@ -127,8 +128,14 @@ class PropertyAccessorInlineLowering(private val context: CommonBackendContext)
 
         private fun isSimpleSetter(callee: IrSimpleFunction, backingField: IrField): Boolean {
             val body = callee.body?.let { it as IrBlockBody } ?: return false
-
-            val stmt = body.statements.singleOrNull() ?: return false
+            val statementsSizeCheck = when (body.statements.size) {
+                1 -> true
+                // In K/N backend this lowering should be called after devirtualization. At this point IrReturns are already added.
+                2 -> (body.statements[1] as? IrReturn)?.value?.type?.isUnit() == true
+                else -> false
+            }
+            if (!statementsSizeCheck) return false
+            val stmt = body.statements[0]
             val setFieldStmt = stmt as? IrSetField ?: return false
             if (setFieldStmt.symbol !== backingField.symbol) return false
 

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/ToplevelPhases.kt

@@ -394,14 +394,15 @@ internal val bitcodePhase = NamedCompilerPhase(
         name = "Bitcode",
         description = "LLVM Bitcode generation",
         lower = contextLLVMSetupPhase then
-                propertyAccessorInlinePhase then // Have to run after link dependencies phase, because fields
-                                                 // from dependencies can be changed during lowerings.
                 returnsInsertionPhase then
                 buildDFGPhase then
                 devirtualizationAnalysisPhase then
                 dcePhase then
                 removeRedundantCallsToFileInitializersPhase then
                 devirtualizationPhase then
+                propertyAccessorInlinePhase then // Have to run after link dependencies phase, because fields
+                                                 // from dependencies can be changed during lowerings.
+                inlineClassPropertyAccessorsPhase then
                 redundantCoercionsCleaningPhase then
                 createLLVMDeclarationsPhase then
                 ghaPhase then
@@ -493,6 +494,7 @@ internal fun PhaseConfig.konanPhasesConfig(config: KonanConfig) {
         // Inline accessors only in optimized builds due to separate compilation and possibility to get broken
         // debug information.
         disableUnless(propertyAccessorInlinePhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
+        disableUnless(inlineClassPropertyAccessorsPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(dcePhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(removeRedundantCallsToFileInitializersPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(ghaPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/BitcodePhases.kt

@@ -13,6 +13,7 @@ import org.jetbrains.kotlin.backend.common.phaser.namedUnitPhase
 import org.jetbrains.kotlin.backend.konan.*
 import org.jetbrains.kotlin.backend.konan.descriptors.GlobalHierarchyAnalysis
 import org.jetbrains.kotlin.backend.konan.lower.DECLARATION_ORIGIN_BRIDGE_METHOD
+import org.jetbrains.kotlin.backend.konan.lower.InlineClassPropertyAccessorsLowering
 import org.jetbrains.kotlin.backend.konan.lower.RedundantCoercionsCleaner
 import org.jetbrains.kotlin.backend.konan.lower.ReturnsInsertionLowering
 import org.jetbrains.kotlin.backend.konan.optimizations.*
@@ -121,6 +122,12 @@ internal val returnsInsertionPhase = makeKonanModuleOpPhase(
         op = { context, irModule -> irModule.files.forEach { ReturnsInsertionLowering(context).lower(it) } }
 )
 
+internal val inlineClassPropertyAccessorsPhase = makeKonanModuleOpPhase(
+        name = "InlineClassPropertyAccessorsLowering",
+        description = "Inline class property accessors",
+        op = { context, irModule -> irModule.files.forEach { InlineClassPropertyAccessorsLowering(context).lower(it) } }
+)
+
 internal val devirtualizationAnalysisPhase = makeKonanModuleOpPhase(
         name = "DevirtualizationAnalysis",
         description = "Devirtualization analysis",
@@ -201,11 +208,6 @@ internal val dcePhase = makeKonanModuleOpPhase(
                 }
             })
 
-            // TODO: Bridge function normally calls it's target, but it could be optimized out by Autoboxing and InlinePropertyAccessor
-            //       lowerings. But Devirtualization doesn't handle this correctly, and can replace bridge call with call of it's target.
-            //       So it's safer not to remove target if bridge is preserved, even if target itself is not called directly
-            referencedFunctions.addAll(referencedFunctions.mapNotNull { it.origin.safeAs<DECLARATION_ORIGIN_BRIDGE_METHOD>()?.bridgeTarget })
-
             context.irModule!!.transformChildrenVoid(object: IrElementTransformerVoid() {
                 override fun visitFile(declaration: IrFile): IrFile {
                     declaration.declarations.removeAll {

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/Autoboxing.kt

@@ -311,30 +311,6 @@ private class InlineClassTransformer(private val context: Context) : IrBuildingT
         return declaration
     }
 
-    override fun visitCall(expression: IrCall): IrExpression {
-        expression.transformChildrenVoid(this)
-        // Make replacement only in optimized builds due to separate compilation and possibility to get broken
-        // debug information.
-        if (!context.shouldOptimize())
-            return expression
-
-        val property = expression.symbol.owner.correspondingPropertySymbol?.owner ?: return expression
-
-        property.parent.let {
-            if (it is IrClass && it.isInline && property.backingField != null) {
-                expression.dispatchReceiver?.let { receiver ->
-                    return builder.at(expression)
-                            .irCall(symbols.reinterpret, expression.type, listOf(receiver.type, expression.type))
-                            .apply {
-                                extensionReceiver = receiver
-                            }
-                }
-            }
-        }
-
-        return expression
-    }
-
     private fun IrBuilderWithScope.irIsNull(expression: IrExpression): IrExpression {
         val binary = expression.type.computeBinaryType()
         return when (binary) {

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/lower/InlineClassPropertyAccessorsLowering.kt

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2010-2021 JetBrains s.r.o. Use of this source code is governed by the Apache 2.0 license
+ * that can be found in the LICENSE file.
+ */
+
+package org.jetbrains.kotlin.backend.konan.lower
+
+
+import org.jetbrains.kotlin.backend.common.FileLoweringPass
+
+import org.jetbrains.kotlin.backend.common.lower.*
+import org.jetbrains.kotlin.backend.konan.*
+import org.jetbrains.kotlin.ir.builders.*
+import org.jetbrains.kotlin.ir.declarations.*
+import org.jetbrains.kotlin.ir.expressions.*
+import org.jetbrains.kotlin.ir.visitors.*
+
+
+/**
+ * Boxes and unboxes values of value types when necessary.
+ */
+internal class InlineClassPropertyAccessorsLowering(val context: Context) : FileLoweringPass {
+
+    private val transformer = InlineClassAccessorsTransformer(context)
+
+    override fun lower(irFile: IrFile) {
+        irFile.transformChildrenVoid(transformer)
+    }
+
+}
+
+private class InlineClassAccessorsTransformer(private val context: Context) : IrBuildingTransformer(context) {
+
+    private val symbols = context.ir.symbols
+
+    override fun visitCall(expression: IrCall): IrExpression {
+        expression.transformChildrenVoid(this)
+
+        val property = expression.symbol.owner.correspondingPropertySymbol?.owner ?: return expression
+
+        property.parent.let {
+            if (it is IrClass && it.isInline && property.backingField != null) {
+                expression.dispatchReceiver?.let { receiver ->
+                    return builder.at(expression)
+                            .irCall(symbols.reinterpret, expression.type, listOf(receiver.type, expression.type))
+                            .apply {
+                                extensionReceiver = receiver
+                            }
+                }
+            }
+        }
+
+        return expression
+    }
+}