From 31670622c00af6d6f1f6a30119991ad389a824b7 Mon Sep 17 00:00:00 2001
From: pyos <pyos@google.com>
Date: Thu, 25 Apr 2019 10:24:43 +0200
Subject: [PATCH] Remove a redundant JVM-specific lowering

---
 .../jetbrains/kotlin/backend/jvm/JvmLower.kt  |  1 -
 .../jvm/lower/JvmTypeOperatorLoweringPhase.kt | 58 -------------------
 2 files changed, 59 deletions(-)
 delete mode 100644 compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmTypeOperatorLoweringPhase.kt

diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt
index 1bbf435b5c9..2a8e3829ac1 100644
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt
+++ b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/JvmLower.kt
@@ -104,7 +104,6 @@ val jvmPhases = namedIrFilePhase(
 
             tailrecPhase then
             toArrayPhase then
-            jvmTypeOperatorLoweringPhase then
             flattenStringConcatenationPhase then
             foldConstantLoweringPhase then
             jvmBuiltinOptimizationLoweringPhase then
diff --git a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmTypeOperatorLoweringPhase.kt b/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmTypeOperatorLoweringPhase.kt
deleted file mode 100644
index 5ec1e00f579..00000000000
--- a/compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/lower/JvmTypeOperatorLoweringPhase.kt
+++ /dev/null
@@ -1,58 +0,0 @@
-/*
- * Copyright 2010-2019 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.jvm.lower
-
-import org.jetbrains.kotlin.backend.common.FileLoweringPass
-import org.jetbrains.kotlin.backend.common.phaser.makeIrFilePhase
-import org.jetbrains.kotlin.backend.jvm.JvmBackendContext
-import org.jetbrains.kotlin.ir.declarations.IrFile
-import org.jetbrains.kotlin.ir.expressions.*
-import org.jetbrains.kotlin.ir.expressions.impl.IrBlockImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrConstImpl
-import org.jetbrains.kotlin.ir.expressions.impl.IrElseBranchImpl
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformerVoid
-import org.jetbrains.kotlin.ir.visitors.transformChildrenVoid
-
-internal val jvmTypeOperatorLoweringPhase = makeIrFilePhase(
-    ::JvmTypeOperatorLowering,
-    name = "JvmTypeOperatorLoweringPhase",
-    description = "Handle JVM-specific type operator lowerings"
-)
-
-private class JvmTypeOperatorLowering(val context: JvmBackendContext) : FileLoweringPass {
-    override fun lower(irFile: IrFile) {
-        irFile.transformChildrenVoid(object : IrElementTransformerVoid() {
-
-            // Make sure that When expressions that are coerced to unit always produces a value.
-            // If the When expression do not have an else branch, we add one of the right type
-            // so that a value is always produced that can be pop off the stack.
-            //
-            // Otherwise, code such as
-            //
-            // val b = getBoolean()
-            // if (b) 5
-            // else if (b) 4
-            //
-            // leads to the generation of code that will underflow the stack.
-            override fun visitTypeOperator(expression: IrTypeOperatorCall): IrExpression {
-                expression.transformChildrenVoid(this)
-                if (expression.operator === IrTypeOperator.IMPLICIT_COERCION_TO_UNIT) {
-                    val argument = expression.argument
-                    if (argument is IrWhen
-                        && argument.branches.size > 0
-                        && argument.branches.last() !is IrElseBranch) {
-                        argument.branches.add(
-                            IrElseBranchImpl(
-                                IrConstImpl.constTrue(argument.startOffset, argument.endOffset, context.irBuiltIns.booleanType),
-                                IrBlockImpl(argument.startOffset, argument.endOffset, argument.type))
-                        )
-                    }
-                }
-                return expression
-            }
-        })
-    }
-}