Inline properties accessors for release builds (#4570)

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

@@ -8,6 +8,7 @@ import org.jetbrains.kotlin.backend.common.lower.inline.LocalClassesInInlineFunc
 import org.jetbrains.kotlin.backend.common.lower.inline.LocalClassesInInlineLambdasLowering
 import org.jetbrains.kotlin.backend.common.lower.loops.ForLoopsLowering
 import org.jetbrains.kotlin.backend.common.lower.optimizations.FoldConstantLowering
+import org.jetbrains.kotlin.backend.common.lower.optimizations.PropertyAccessorInlineLowering
 import org.jetbrains.kotlin.backend.common.phaser.*
 import org.jetbrains.kotlin.backend.konan.lower.*
 import org.jetbrains.kotlin.backend.konan.lower.FinallyBlocksLowering
@@ -106,6 +107,12 @@ internal val lateinitPhase = makeKonanModuleOpPhase(
         description = "Lateinit properties lowering"
 )
 
+internal val propertyAccessorInlinePhase = makeKonanModuleLoweringPhase(
+        ::PropertyAccessorInlineLowering,
+        name = "PropertyAccessorInline",
+        description = "Property accessor inline lowering"
+)
+
 internal val sharedVariablesPhase = makeKonanModuleLoweringPhase(
         ::SharedVariablesLowering,
         name = "SharedVariables",

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

@@ -391,6 +391,8 @@ internal val bitcodePhase = NamedCompilerPhase(
                 ghaPhase then
                 RTTIPhase then
                 generateDebugInfoHeaderPhase then
+                propertyAccessorInlinePhase then // Have to run after link dependencies phase, because fields
+                                                 // from dependencies can be changed during lowerings.
                 escapeAnalysisPhase then
                 localEscapeAnalysisPhase then
                 codegenPhase then
@@ -468,6 +470,9 @@ internal fun PhaseConfig.konanPhasesConfig(config: KonanConfig) {
         disableUnless(buildDFGPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(devirtualizationPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(escapeAnalysisPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
+        // Inline accessors only in optimized builds due to separate compilation and possibility to get broken
+        // debug information.
+        disableUnless(propertyAccessorInlinePhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(dcePhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(ghaPhase, getBoolean(KonanConfigKeys.OPTIMIZATION))
         disableUnless(verifyBitcodePhase, config.needCompilerVerification || getBoolean(KonanConfigKeys.VERIFY_BITCODE))

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

@@ -309,6 +309,30 @@ 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/InitializersLowering.kt

@@ -82,9 +82,11 @@ internal class InitializersLowering(val context: CommonBackendContext) : ClassLo
                     )
 
                     // We shall keep initializer for constants for compile-time instantiation.
+                    // We suppose that if the property is const, then its initializer is IrConst.
+                    // If this requirement isn't satisfied, then PropertyAccessorInlineLowering can fail.
                     declaration.initializer =
                             if (initExpression is IrConst<*> &&
-                                    (initExpression.type.isPrimitiveType() || initExpression.type.isString())) {
+                                    declaration.correspondingPropertySymbol?.owner?.isConst == true) {
                                 IrExpressionBodyImpl(initExpression.copy())
                             } else {
                                 null