KNVE: support in JVM_IR and JS_IR

2020-04-20 14:45:18 +03:00
parent b06780988d
commit 05cb0e8994
12 changed files with 150 additions and 14 deletions
@@ -232,6 +232,9 @@ abstract class Symbols<out T : CommonBackendContext>(val context: T, symbolTable

    abstract val ThrowUninitializedPropertyAccessException: IrSimpleFunctionSymbol

+    open val ThrowKotlinNothingValueException: IrSimpleFunctionSymbol
+        get() = TODO("Support KotlinNothingValueException in Kotlin/Native and make this val abstract")
+
    abstract val stringBuilder: IrClassSymbol

    abstract val defaultConstructorMarker: IrClassSymbol
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.backend.common.lower
+
+import org.jetbrains.kotlin.backend.common.BodyLoweringPass
+import org.jetbrains.kotlin.backend.common.CommonBackendContext
+import org.jetbrains.kotlin.ir.builders.irCall
+import org.jetbrains.kotlin.ir.declarations.IrDeclaration
+import org.jetbrains.kotlin.ir.declarations.IrSymbolDeclaration
+import org.jetbrains.kotlin.ir.expressions.IrBody
+import org.jetbrains.kotlin.ir.expressions.IrCall
+import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.expressions.impl.IrCallImpl
+import org.jetbrains.kotlin.ir.symbols.IrSymbol
+import org.jetbrains.kotlin.ir.types.isNothing
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
+import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
+
+class KotlinNothingValueExceptionLowering(val backendContext: CommonBackendContext) : BodyLoweringPass {
+    override fun lower(irBody: IrBody, container: IrDeclaration) {
+        irBody.transformChildrenVoid(
+            Transformer((container as IrSymbolDeclaration<*>).symbol)
+        )
+    }
+
+    private inner class Transformer(val parent: IrSymbol) : IrElementTransformerVoid() {
+        override fun visitCall(expression: IrCall): IrExpression =
+            if (expression.type.isNothing()) {
+                // Replace call 'foo' of type 'kotlin.Nothing' with a block:
+                //
+                //  {
+                //      [ call 'foo' with type: 'kotlin.Unit' ]
+                //      call ThrowKotlinNothingValueException(): Nothing
+                //  }: Nothing
+                //
+                // Changing type of 'foo' to 'kotlin.Unit' is requires so that the 'ThrowKotlinNothingValueException(): Nothing'
+                // is not considered dead code and is not removed.
+                // Note that type 'kotlin.Nothing' might be inferred in some cases of projected types.
+                // See KT-30330 for an example of such code where call of type 'kotlin.Nothing' terminates and produces some value
+                // (although doing so by subverting the type system).
+                backendContext.createIrBuilder(parent, expression.startOffset, expression.endOffset).run {
+                    irBlock(expression, null, context.irBuiltIns.nothingType) {
+                        +changeTypeToUnit(expression)
+                        +irCall(backendContext.ir.symbols.ThrowKotlinNothingValueException)
+                    }
+                }
+            } else {
+                expression
+            }
+
+        private fun changeTypeToUnit(call: IrCall): IrCall =
+            IrCallImpl(
+                call.startOffset, call.endOffset,
+                backendContext.irBuiltIns.unitType,
+                call.symbol,
+                call.typeArgumentsCount, call.valueArgumentsCount, call.origin, call.superQualifierSymbol
+            ).also { newCall ->
+                for (i in 0 until call.typeArgumentsCount) {
+                    newCall.putTypeArgument(i, call.getTypeArgument(i))
+                }
+                newCall.dispatchReceiver = call.dispatchReceiver
+                newCall.extensionReceiver = call.extensionReceiver
+                for (i in 0 until call.valueArgumentsCount) {
+                    newCall.putValueArgument(i, call.getValueArgument(i))
+                }
+            }
+    }
+}