Refactor IrWhen.

compiler/ir/backend.jvm/src/org/jetbrains/kotlin/backend/jvm/ExpressionCodegen.kt

@@ -30,8 +30,6 @@ import org.jetbrains.kotlin.ir.declarations.IrVariable
 import org.jetbrains.kotlin.ir.expressions.*
 import org.jetbrains.kotlin.ir.expressions.impl.IrIfThenElseImpl
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
-import org.jetbrains.kotlin.psi.KtCallExpression
-import org.jetbrains.kotlin.resolve.calls.model.ResolvedCall
 import org.jetbrains.kotlin.resolve.jvm.AsmTypes
 import org.jetbrains.kotlin.resolve.jvm.AsmTypes.OBJECT_TYPE
 import org.jetbrains.kotlin.types.KotlinType
@@ -303,13 +301,13 @@ class ExpressionCodegen(
         /*TODO */
         if (expression is IrIfThenElseImpl) {
             val elseLabel = Label()
-            val condition = expression.getNthCondition(0)!!
+            val condition = expression.branches[0].condition
             gen(condition, data)
             BranchedValue.condJump(StackValue.onStack(condition.asmType), elseLabel, true, mv)
 
             val end = Label()
 
-            expression.getNthResult(0)!!.apply {
+            expression.branches[0].result.apply {
                 gen(this, data)
                 coerceNotToUnit(this.asmType, expression.asmType)
             }
@@ -317,7 +315,7 @@ class ExpressionCodegen(
             mv.goTo(end)
             mv.mark(elseLabel)
 
-            expression.getNthResult(1)?.apply {
+            expression.branches.getOrNull(1)?.result?.apply {
                 gen(this, data)
                 coerceNotToUnit(this.asmType, expression.asmType)
             }

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/generators/BranchingExpressionGenerator.kt

@@ -25,6 +25,7 @@ import org.jetbrains.kotlin.psi.psiUtil.startOffset
 import org.jetbrains.kotlin.psi2ir.defaultLoad
 import org.jetbrains.kotlin.psi2ir.deparenthesize
 import org.jetbrains.kotlin.resolve.BindingContext
+import org.jetbrains.kotlin.types.KotlinType
 import org.jetbrains.kotlin.utils.SmartList
 
 class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : StatementGeneratorExtension(statementGenerator) {
@@ -32,13 +33,13 @@ class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : Sta
         val resultType = getInferredTypeWithImplicitCastsOrFail(expression)
 
         var ktLastIf: KtIfExpression = expression
-        val irBranches = SmartList<Pair<IrExpression, IrExpression>>()
+        val irBranches = SmartList<IrBranch>()
         var irElseBranch: IrExpression? = null
 
         whenBranches@while (true) {
             val irCondition = statementGenerator.generateExpression(ktLastIf.condition!!)
             val irThenBranch = statementGenerator.generateExpression(ktLastIf.then!!)
-            irBranches.add(Pair(irCondition, irThenBranch))
+            irBranches.add(IrBranchImpl(irCondition, irThenBranch))
 
             val ktElse = ktLastIf.`else`?.deparenthesize()
             when (ktElse) {
@@ -52,19 +53,29 @@ class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : Sta
             }
         }
 
-        return if (irBranches.size == 1) {
+        return createIrWhen(expression, irBranches, irElseBranch, resultType)
-            val (irCondition, irThenBranch) = irBranches[0]
-            IrIfThenElseImpl(expression.startOffset, expression.endOffset, resultType,
-                             irCondition, irThenBranch, irElseBranch, IrStatementOrigin.IF)
     }
-        else {
+
-            val irWhen = IrWhenImpl(expression.startOffset, expression.endOffset, resultType, IrStatementOrigin.WHEN)
+    private fun createIrWhen(
-            for ((irCondition, irThenBranch) in irBranches) {
+            ktIf: KtIfExpression,
-                irWhen.addBranch(irCondition, irThenBranch)
+            irBranches: List<IrBranch>,
+            irElseResult: IrExpression?,
+            resultType: KotlinType
+    ): IrWhen {
+        if (irBranches.size == 1) {
+            return IrIfThenElseImpl(ktIf.startOffset, ktIf.endOffset, resultType,
+                                    irBranches[0].condition, irBranches[0].result, irElseResult)
         }
-            irWhen.elseBranch = irElseBranch
+
-            irWhen
+        val irWhen = IrWhenImpl(ktIf.startOffset, ktIf.endOffset, resultType, IrStatementOrigin.WHEN)
+
+        irWhen.branches.addAll(irBranches)
+
+        irElseResult?.let {
+            irWhen.branches.add(IrBranchImpl.elseBranch(it))
         }
+
+        return irWhen
     }
 
     fun generateWhenExpression(expression: KtWhenExpression): IrExpression {
@@ -78,7 +89,8 @@ class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : Sta
 
         for (ktEntry in expression.entries) {
             if (ktEntry.isElse) {
-                irWhen.elseBranch = statementGenerator.generateExpression(ktEntry.expression!!)
+                val irElseResult = statementGenerator.generateExpression(ktEntry.expression!!)
+                irWhen.branches.add(IrBranchImpl.elseBranch(irElseResult))
                 break
             }
 
@@ -94,7 +106,7 @@ class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : Sta
             }
 
             val irBranchResult = statementGenerator.generateExpression(ktEntry.expression!!)
-            irWhen.addBranch(irBranchCondition!!, irBranchResult)
+            irWhen.branches.add(IrBranchImpl(irBranchCondition!!, irBranchResult))
         }
 
         return generateWhenBody(expression, irSubject, irWhen)
@@ -102,13 +114,13 @@ class BranchingExpressionGenerator(statementGenerator: StatementGenerator) : Sta
 
     private fun generateWhenBody(expression: KtWhenExpression, irSubject: IrVariable?, irWhen: IrWhen): IrExpression {
         if (irSubject == null) {
-            if (irWhen.branchesCount == 0 && irWhen.elseBranch == null)
+            if (irWhen.branches.isEmpty())
                 return IrBlockImpl(expression.startOffset, expression.endOffset, context.builtIns.unitType, IrStatementOrigin.WHEN)
             else
                 return irWhen
         }
         else {
-            if (irWhen.branchesCount == 0) {
+            if (irWhen.branches.isEmpty()) {
                 val irBlock = IrBlockImpl(expression.startOffset, expression.endOffset, context.builtIns.unitType, IrStatementOrigin.WHEN)
                 irBlock.statements.add(irSubject)
                 return irBlock

compiler/ir/ir.psi2ir/src/org/jetbrains/kotlin/psi2ir/transformations/InsertImplicitCasts.kt

@@ -127,16 +127,11 @@ class InsertImplicitCasts(val builtIns: KotlinBuiltIns): IrElementTransformerVoi
 
         val resultType = expression.type
 
-        for (i in expression.branchIndices) {
+        for (irBranch in expression.branches) {
-            val nthCondition = expression.getNthCondition(i)!!
+            irBranch.condition = irBranch.condition.cast(builtIns.booleanType)
-            val nthResult = expression.getNthResult(i)!!
+            irBranch.result = irBranch.result.cast(resultType)
-
-            expression.putNthCondition(i, nthCondition.cast(builtIns.booleanType))
-            expression.putNthResult(i, nthResult.cast(resultType))
         }
 
-        expression.elseBranch = expression.elseBranch?.cast(resultType)
-
         return expression
     }
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/IrWhen.kt

@@ -16,19 +16,23 @@
 
 package org.jetbrains.kotlin.ir.expressions
 
+import org.jetbrains.kotlin.ir.IrElement
+import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
+import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
+
 interface IrWhen : IrExpression {
     val origin: IrStatementOrigin?
 
-    val branchesCount: Int
+    val branches: MutableList<IrBranch>
-
-    fun getNthCondition(n: Int): IrExpression?
-    fun getNthResult(n: Int): IrExpression?
-
-    fun putNthCondition(n: Int, expression: IrExpression)
-    fun putNthResult(n: Int, expression: IrExpression)
-
-    var elseBranch: IrExpression?
 }
 
-val IrWhen.branchIndices: IntRange get() = 0 ..branchesCount - 1
+interface IrBranch : IrElement {
+    var condition: IrExpression
+    var result: IrExpression
 
+    override fun <D> transform(transformer: IrElementTransformer<D>, data: D): IrBranch =
+            transformer.visitBranch(this, data)
+
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+            visitor.visitBranch(this, data)
+}

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/impl/IrIfThenElseImpl.kt

@@ -16,17 +16,19 @@
 
 package org.jetbrains.kotlin.ir.expressions.impl
 
+import org.jetbrains.kotlin.ir.expressions.IrBranch
 import org.jetbrains.kotlin.ir.expressions.IrExpression
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
-import org.jetbrains.kotlin.ir.expressions.IrWhen
-import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
-import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.typeUtil.builtIns
+import org.jetbrains.kotlin.utils.SmartList
 
 class IrIfThenElseImpl(
         startOffset: Int, endOffset: Int, type: KotlinType,
         override val origin: IrStatementOrigin? = null
-) : IrExpressionBase(startOffset, endOffset, type), IrWhen {
+) : IrWhenBase(startOffset, endOffset, type) {
+    override val branches: MutableList<IrBranch> = SmartList()
+
     constructor(
             startOffset: Int, endOffset: Int, type: KotlinType,
             condition: IrExpression,
@@ -34,56 +36,9 @@ class IrIfThenElseImpl(
             elseBranch: IrExpression? = null,
             origin: IrStatementOrigin? = null
     ) : this(startOffset, endOffset, type, origin) {
-        this.condition = condition
+        branches.add(IrBranchImpl(startOffset, endOffset, condition, thenBranch))
-        this.thenBranch = thenBranch
+        if (elseBranch != null) {
-        this.elseBranch = elseBranch
+            branches.add(IrBranchImpl.elseBranch(elseBranch))
         }
-
-    override val branchesCount: Int get() = 1
-
-    override fun getNthCondition(n: Int): IrExpression? =
-            if (n == 0) condition else null
-
-    override fun getNthResult(n: Int): IrExpression? =
-            when (n) {
-                0 -> {
-                    thenBranch
-                }
-                1 -> {
-                    elseBranch
-                }
-                else -> null
-            }
-
-
-    override fun putNthCondition(n: Int, expression: IrExpression) {
-        if (n == 0) condition = expression
-        else throw AssertionError("No such branch $n")
-    }
-
-    override fun putNthResult(n: Int, expression: IrExpression) {
-        if (n == 0) thenBranch = expression
-        else throw AssertionError("No such branch $n")
-    }
-
-    lateinit var condition: IrExpression
-
-    lateinit var thenBranch: IrExpression
-
-    override var elseBranch: IrExpression? = null
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-            visitor.visitWhen(this, data)
-
-    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        condition.accept(visitor, data)
-        thenBranch.accept(visitor, data)
-        elseBranch?.accept(visitor, data)
-    }
-
-    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        condition = condition.transform(transformer, data)
-        thenBranch = thenBranch.transform(transformer, data)
-        elseBranch = elseBranch?.transform(transformer, data)
     }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/expressions/impl/IrWhenImpl.kt

@@ -16,57 +16,58 @@
 
 package org.jetbrains.kotlin.ir.expressions.impl
 
-import org.jetbrains.kotlin.ir.expressions.IrExpression
+import org.jetbrains.kotlin.ir.IrElementBase
-import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
+import org.jetbrains.kotlin.ir.expressions.*
-import org.jetbrains.kotlin.ir.expressions.IrWhen
 import org.jetbrains.kotlin.ir.visitors.IrElementTransformer
 import org.jetbrains.kotlin.ir.visitors.IrElementVisitor
 import org.jetbrains.kotlin.types.KotlinType
+import org.jetbrains.kotlin.types.typeUtil.builtIns
 import java.util.*
 
+abstract class IrWhenBase(startOffset: Int, endOffset: Int, type: KotlinType, override val origin: IrStatementOrigin? = null) :
+        IrExpressionBase(startOffset, endOffset, type), IrWhen {
+    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
+            visitor.visitWhen(this, data)
+
+    override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
+        branches.forEach { it.accept(visitor, data) }
+    }
+
+    override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
+        branches.forEachIndexed { i, irBranch ->
+            branches[i] = irBranch.transform(transformer, data)
+        }
+    }
+}
+
 class IrWhenImpl(
         startOffset: Int,
         endOffset: Int,
         type: KotlinType,
         override val origin: IrStatementOrigin? = null
-) : IrExpressionBase(startOffset, endOffset, type), IrWhen {
+) : IrWhenBase(startOffset, endOffset, type) {
-    private val branchParts = ArrayList<IrExpression>()
+    override val branches: MutableList<IrBranch> = ArrayList()
+}
 
-    fun addBranch(condition: IrExpression, result: IrExpression) {
+class IrBranchImpl(startOffset: Int, endOffset: Int, override var condition: IrExpression, override var result: IrExpression) :
-        branchParts.add(condition)
+        IrElementBase(startOffset, endOffset), IrBranch {
-        branchParts.add(result)
+    constructor(condition: IrExpression, result: IrExpression) : this(condition.startOffset, condition.endOffset, condition, result)
-    }
-
-    override var elseBranch: IrExpression? = null
-
-    override val branchesCount: Int get() = branchParts.size / 2
-
-    override fun getNthCondition(n: Int): IrExpression? =
-            branchParts.getOrNull(n * 2)
-
-    override fun getNthResult(n: Int): IrExpression? =
-            branchParts.getOrNull(n * 2 + 1)
-
-    override fun putNthCondition(n: Int, expression: IrExpression) {
-        branchParts[n * 2] = expression
-    }
-
-    override fun putNthResult(n: Int, expression: IrExpression) {
-        branchParts[n * 2 + 1] = expression
-    }
-
-    override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R =
-            visitor.visitWhen(this, data)
 
     override fun <D> acceptChildren(visitor: IrElementVisitor<Unit, D>, data: D) {
-        branchParts.forEach { it.accept(visitor, data) }
+        condition.accept(visitor, data)
-        elseBranch?.accept(visitor, data)
+        result.accept(visitor, data)
     }
 
     override fun <D> transformChildren(transformer: IrElementTransformer<D>, data: D) {
-        branchParts.forEachIndexed { i, irExpression ->
+        condition = condition.transform(transformer, data)
-            branchParts[i] = irExpression.transform(transformer, data)
+        result = result.transform(transformer, data)
     }
-        elseBranch = elseBranch?.transform(transformer, data)
+
+    companion object {
+        fun elseBranch(result: IrExpression) =
+                IrBranchImpl(
+                        IrConstImpl.boolean(result.startOffset, result.endOffset, result.type.builtIns.booleanType, true),
+                        result
+                )
     }
 }

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/DumpIrTree.kt

@@ -131,11 +131,16 @@ class DumpIrTreeVisitor(out: Appendable): IrElementVisitor<Unit, String> {
 
     override fun visitWhen(expression: IrWhen, data: String) {
         expression.dumpLabeledElementWith(data) {
-            for (i in 0 .. expression.branchesCount - 1) {
+            expression.branches.forEach {
-                expression.getNthCondition(i)!!.accept(this, "if")
+                it.accept(this, "")
-                expression.getNthResult(i)!!.accept(this, "then")
             }
-            expression.elseBranch?.accept(this, "else")
+        }
+    }
+
+    override fun visitBranch(branch: IrBranch, data: String) {
+        branch.dumpLabeledElementWith(data) {
+            branch.condition.accept(this, "if")
+            branch.result.accept(this, "then")
         }
     }
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/RenderIrElement.kt

@@ -155,6 +155,9 @@ class RenderIrElementVisitor : IrElementVisitor<String, Nothing?> {
     override fun visitWhen(expression: IrWhen, data: Nothing?): String =
             "WHEN type=${expression.type.render()} origin=${expression.origin}"
 
+    override fun visitBranch(branch: IrBranch, data: Nothing?): String =
+            "BRANCH"
+
     override fun visitWhileLoop(loop: IrWhileLoop, data: Nothing?): String =
             "WHILE label=${loop.label} origin=${loop.origin}"
 

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementTransformer.kt

@@ -92,6 +92,13 @@ interface IrElementTransformer<in D> : IrElementVisitor<IrElement, D> {
     override fun visitTypeOperator(expression: IrTypeOperatorCall, data: D) = visitExpression(expression, data)
 
     override fun visitWhen(expression: IrWhen, data: D) = visitExpression(expression, data)
+
+    override fun visitBranch(branch: IrBranch, data: D): IrBranch =
+            branch.apply {
+                condition = condition.transform(this@IrElementTransformer, data)
+                result = result.transform(this@IrElementTransformer, data)
+            }
+
     override fun visitLoop(loop: IrLoop, data: D) = visitExpression(loop, data)
     override fun visitWhileLoop(loop: IrWhileLoop, data: D) = visitLoop(loop, data)
     override fun visitDoWhileLoop(loop: IrDoWhileLoop, data: D) = visitLoop(loop, data)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementVisitor.kt

@@ -78,6 +78,7 @@ interface IrElementVisitor<out R, in D> {
     fun visitTypeOperator(expression: IrTypeOperatorCall, data: D) = visitExpression(expression, data)
 
     fun visitWhen(expression: IrWhen, data: D) = visitExpression(expression, data)
+    fun visitBranch(branch: IrBranch, data: D) = visitElement(branch, data)
     fun visitLoop(loop: IrLoop, data: D) = visitExpression(loop, data)
     fun visitWhileLoop(loop: IrWhileLoop, data: D) = visitLoop(loop, data)
     fun visitDoWhileLoop(loop: IrDoWhileLoop, data: D) = visitLoop(loop, data)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/visitors/IrElementVisitorVoid.kt

@@ -165,6 +165,9 @@ interface IrElementVisitorVoid : IrElementVisitor<Unit, Nothing?> {
     fun visitWhen(expression: IrWhen) = visitExpression(expression)
     override fun visitWhen(expression: IrWhen, data: Nothing?) = visitWhen(expression)
 
+    fun visitBranch(branch: IrBranch) = visitElement(branch)
+    override fun visitBranch(branch: IrBranch, data: Nothing?) = visitBranch(branch)
+
     fun visitLoop(loop: IrLoop) = visitExpression(loop)
     override fun visitLoop(loop: IrLoop, data: Nothing?) = visitLoop(loop)
 

compiler/testData/ir/irText/classes/dataClasses.txt

@@ -99,12 +99,14 @@ FILE /dataClasses.kt
     FUN GENERATED_DATA_CLASS_MEMBER public open override fun equals(other: kotlin.Any?): kotlin.Boolean
       BLOCK_BODY
         WHEN type=kotlin.Unit origin=null
+          BRANCH
             if: CALL 'EQEQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQEQ
               arg0: THIS of 'Test1' type=Test1
               arg1: GET_VAR 'value-parameter other: Any?' type=kotlin.Any? origin=null
             then: RETURN type=kotlin.Nothing from='equals(Any?): Boolean'
               CONST Boolean type=kotlin.Boolean value='true'
         WHEN type=kotlin.Unit origin=null
+          BRANCH
             if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=Test1
               GET_VAR 'value-parameter other: Any?' type=kotlin.Any? origin=null
             then: RETURN type=kotlin.Nothing from='equals(Any?): Boolean'
@@ -113,6 +115,7 @@ FILE /dataClasses.kt
           TYPE_OP origin=CAST typeOperand=Test1
             GET_VAR 'value-parameter other: Any?' type=kotlin.Any? origin=null
         WHEN type=kotlin.Unit origin=null
+          BRANCH
             if: CALL 'NOT(Boolean): Boolean' type=kotlin.Boolean origin=EXCLEQ
               arg0: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EXCLEQ
                 arg0: CALL '<get-x>(): Int' type=kotlin.Int origin=GET_PROPERTY
@@ -122,6 +125,7 @@ FILE /dataClasses.kt
             then: RETURN type=kotlin.Nothing from='equals(Any?): Boolean'
               CONST Boolean type=kotlin.Boolean value='false'
         WHEN type=kotlin.Unit origin=null
+          BRANCH
             if: CALL 'NOT(Boolean): Boolean' type=kotlin.Boolean origin=EXCLEQ
               arg0: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EXCLEQ
                 arg0: CALL '<get-y>(): String' type=kotlin.String origin=GET_PROPERTY
@@ -131,6 +135,7 @@ FILE /dataClasses.kt
             then: RETURN type=kotlin.Nothing from='equals(Any?): Boolean'
               CONST Boolean type=kotlin.Boolean value='false'
         WHEN type=kotlin.Unit origin=null
+          BRANCH
             if: CALL 'NOT(Boolean): Boolean' type=kotlin.Boolean origin=EXCLEQ
               arg0: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EXCLEQ
                 arg0: CALL '<get-z>(): Any' type=kotlin.Any origin=GET_PROPERTY

compiler/testData/ir/irText/expressions/bangbang.txt

@@ -6,11 +6,14 @@ FILE /bangbang.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_notnull: kotlin.Any?
             GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
           WHEN type=kotlin.Any origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_notnull: Any?' type=kotlin.Any? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CALL 'THROW_NPE(): Nothing' type=kotlin.Nothing origin=EXCLEXCL
-            else: GET_VAR 'tmp0_notnull: Any?' type=kotlin.Any? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: GET_VAR 'tmp0_notnull: Any?' type=kotlin.Any? origin=null
   FUN public fun test2(a: kotlin.Any?): kotlin.Int
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test2(Any?): Int'
@@ -20,15 +23,21 @@ FILE /bangbang.kt
               VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.Any?
                 GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
               WHEN type=kotlin.Int? origin=SAFE_CALL
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_safe_receiver: Any?' type=kotlin.Any? origin=null
                     arg1: CONST Null type=kotlin.Nothing? value='null'
                   then: CONST Null type=kotlin.Nothing? value='null'
-                else: CALL 'hashCode(): Int' type=kotlin.Int origin=null
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL 'hashCode(): Int' type=kotlin.Int origin=null
                     $this: GET_VAR 'tmp0_safe_receiver: Any?' type=kotlin.Any? origin=null
           WHEN type=kotlin.Int origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp1_notnull: Int?' type=kotlin.Int? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CALL 'THROW_NPE(): Nothing' type=kotlin.Nothing origin=EXCLEXCL
-            else: GET_VAR 'tmp1_notnull: Int?' type=kotlin.Int? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: GET_VAR 'tmp1_notnull: Int?' type=kotlin.Int? origin=null

compiler/testData/ir/irText/expressions/booleanOperators.txt

@@ -3,16 +3,22 @@ FILE /booleanOperators.kt
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test1(Boolean, Boolean): Boolean'
         WHEN type=kotlin.Boolean origin=ANDAND
+          BRANCH
             if: GET_VAR 'value-parameter a: Boolean' type=kotlin.Boolean origin=null
             then: GET_VAR 'value-parameter b: Boolean' type=kotlin.Boolean origin=null
-          else: CONST Boolean type=kotlin.Boolean value='false'
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CONST Boolean type=kotlin.Boolean value='false'
   FUN public fun test2(a: kotlin.Boolean, b: kotlin.Boolean): kotlin.Boolean
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test2(Boolean, Boolean): Boolean'
         WHEN type=kotlin.Boolean origin=OROR
+          BRANCH
             if: GET_VAR 'value-parameter a: Boolean' type=kotlin.Boolean origin=null
             then: CONST Boolean type=kotlin.Boolean value='true'
-          else: GET_VAR 'value-parameter b: Boolean' type=kotlin.Boolean origin=null
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: GET_VAR 'value-parameter b: Boolean' type=kotlin.Boolean origin=null
   FUN public fun test1x(a: kotlin.Boolean, b: kotlin.Boolean): kotlin.Boolean
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test1x(Boolean, Boolean): Boolean'

compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.txt

@@ -9,11 +9,14 @@ FILE /breakContinueInLoopHeader.kt
               VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.Boolean?
                 GET_VAR 'value-parameter c: Boolean?' type=kotlin.Boolean? origin=null
               WHEN type=kotlin.Boolean origin=null
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_elvis_lhs: Boolean?' type=kotlin.Boolean? origin=null
                     arg1: CONST Null type=kotlin.Nothing? value='null'
                   then: BREAK label=null loop.label=L
-                else: GET_VAR 'tmp0_elvis_lhs: Boolean?' type=kotlin.Boolean? origin=null
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: GET_VAR 'tmp0_elvis_lhs: Boolean?' type=kotlin.Boolean? origin=null
   FUN public fun test2(c: kotlin.Boolean?): kotlin.Unit
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
@@ -24,11 +27,14 @@ FILE /breakContinueInLoopHeader.kt
               VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.Boolean?
                 GET_VAR 'value-parameter c: Boolean?' type=kotlin.Boolean? origin=null
               WHEN type=kotlin.Boolean origin=null
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_elvis_lhs: Boolean?' type=kotlin.Boolean? origin=null
                     arg1: CONST Null type=kotlin.Nothing? value='null'
                   then: CONTINUE label=null loop.label=L
-                else: GET_VAR 'tmp0_elvis_lhs: Boolean?' type=kotlin.Boolean? origin=null
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: GET_VAR 'tmp0_elvis_lhs: Boolean?' type=kotlin.Boolean? origin=null
   FUN public fun test3(ss: kotlin.collections.List<kotlin.String>?): kotlin.Unit
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
@@ -41,11 +47,14 @@ FILE /breakContinueInLoopHeader.kt
                   VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.collections.List<kotlin.String>?
                     GET_VAR 'value-parameter ss: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
                   WHEN type=kotlin.collections.List<kotlin.String> origin=null
+                    BRANCH
                       if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                         arg0: GET_VAR 'tmp0_elvis_lhs: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
                         arg1: CONST Null type=kotlin.Nothing? value='null'
                       then: CONTINUE label=null loop.label=L
-                    else: GET_VAR 'tmp0_elvis_lhs: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
+                    BRANCH
+                      if: CONST Boolean type=kotlin.Boolean value='true'
+                      then: GET_VAR 'tmp0_elvis_lhs: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
             WHILE label=null origin=FOR_LOOP_INNER_WHILE
               condition: CALL 'hasNext(): Boolean' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
                 $this: GET_VAR 'tmp1_iterator: Iterator<String>' type=kotlin.collections.Iterator<kotlin.String> origin=null
@@ -65,11 +74,14 @@ FILE /breakContinueInLoopHeader.kt
                   VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.collections.List<kotlin.String>?
                     GET_VAR 'value-parameter ss: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
                   WHEN type=kotlin.collections.List<kotlin.String> origin=null
+                    BRANCH
                       if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                         arg0: GET_VAR 'tmp0_elvis_lhs: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
                         arg1: CONST Null type=kotlin.Nothing? value='null'
                       then: BREAK label=null loop.label=L
-                    else: GET_VAR 'tmp0_elvis_lhs: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
+                    BRANCH
+                      if: CONST Boolean type=kotlin.Boolean value='true'
+                      then: GET_VAR 'tmp0_elvis_lhs: List<String>?' type=kotlin.collections.List<kotlin.String>? origin=null
             WHILE label=null origin=FOR_LOOP_INNER_WHILE
               condition: CALL 'hasNext(): Boolean' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
                 $this: GET_VAR 'tmp1_iterator: Iterator<String>' type=kotlin.collections.Iterator<kotlin.String> origin=null

compiler/testData/ir/irText/expressions/chainOfSafeCalls.txt

@@ -25,30 +25,42 @@ FILE /chainOfSafeCalls.kt
                       VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: C?
                         GET_VAR 'value-parameter nc: C?' type=C? origin=null
                       WHEN type=C? origin=SAFE_CALL
+                        BRANCH
                           if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                             arg0: GET_VAR 'tmp0_safe_receiver: C?' type=C? origin=null
                             arg1: CONST Null type=kotlin.Nothing? value='null'
                           then: CONST Null type=kotlin.Nothing? value='null'
-                        else: CALL 'foo(): C' type=C origin=null
+                        BRANCH
+                          if: CONST Boolean type=kotlin.Boolean value='true'
+                          then: CALL 'foo(): C' type=C origin=null
                             $this: GET_VAR 'tmp0_safe_receiver: C?' type=C? origin=null
                   WHEN type=C? origin=SAFE_CALL
+                    BRANCH
                       if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                         arg0: GET_VAR 'tmp1_safe_receiver: C?' type=C? origin=null
                         arg1: CONST Null type=kotlin.Nothing? value='null'
                       then: CONST Null type=kotlin.Nothing? value='null'
-                    else: CALL 'bar(): C?' type=C? origin=null
+                    BRANCH
+                      if: CONST Boolean type=kotlin.Boolean value='true'
+                      then: CALL 'bar(): C?' type=C? origin=null
                         $this: GET_VAR 'tmp1_safe_receiver: C?' type=C? origin=null
               WHEN type=C? origin=SAFE_CALL
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp2_safe_receiver: C?' type=C? origin=null
                     arg1: CONST Null type=kotlin.Nothing? value='null'
                   then: CONST Null type=kotlin.Nothing? value='null'
-                else: CALL 'foo(): C' type=C origin=null
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL 'foo(): C' type=C origin=null
                     $this: GET_VAR 'tmp2_safe_receiver: C?' type=C? origin=null
           WHEN type=C? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp3_safe_receiver: C?' type=C? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'foo(): C' type=C origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'foo(): C' type=C origin=null
                 $this: GET_VAR 'tmp3_safe_receiver: C?' type=C? origin=null

compiler/testData/ir/irText/expressions/coercionToUnit.txt

@@ -26,11 +26,14 @@ FILE /coercionToUnit.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: java.io.PrintStream!
             GET_FIELD 'out: PrintStream!' type=java.io.PrintStream! origin=GET_PROPERTY
           WHEN type=kotlin.Unit? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: PrintStream!' type=java.io.PrintStream! origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
                 $this: TYPE_OP origin=IMPLICIT_NOTNULL typeOperand=java.io.PrintStream
                   GET_VAR 'tmp0_safe_receiver: PrintStream!' type=java.io.PrintStream! origin=null
                 p0: CONST String type=kotlin.String value='Hello,'
@@ -39,11 +42,14 @@ FILE /coercionToUnit.kt
           VAR IR_TEMPORARY_VARIABLE val tmp1_safe_receiver: java.io.PrintStream!
             GET_FIELD 'out: PrintStream!' type=java.io.PrintStream! origin=GET_PROPERTY
           WHEN type=kotlin.Unit? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp1_safe_receiver: PrintStream!' type=java.io.PrintStream! origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
                 $this: TYPE_OP origin=IMPLICIT_NOTNULL typeOperand=java.io.PrintStream
                   GET_VAR 'tmp1_safe_receiver: PrintStream!' type=java.io.PrintStream! origin=null
                 p0: CONST String type=kotlin.String value='world!'

compiler/testData/ir/irText/expressions/dotQualified.txt

@@ -11,9 +11,12 @@ FILE /dotQualified.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.String?
             GET_VAR 'value-parameter s: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.Int? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL '<get-length>(): Int' type=kotlin.Int origin=GET_PROPERTY
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL '<get-length>(): Int' type=kotlin.Int origin=GET_PROPERTY
                 $this: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null

compiler/testData/ir/irText/expressions/elvis.txt

@@ -18,11 +18,14 @@ FILE /elvis.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.Any?
             GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
           WHEN type=kotlin.Any origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: GET_VAR 'value-parameter b: Any' type=kotlin.Any origin=null
-            else: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
   FUN public fun test2(a: kotlin.String?, b: kotlin.Any): kotlin.Any
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test2(String?, Any): Any'
@@ -30,19 +33,24 @@ FILE /elvis.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.String?
             GET_VAR 'value-parameter a: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.Any origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_elvis_lhs: String?' type=kotlin.String? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: GET_VAR 'value-parameter b: Any' type=kotlin.Any origin=null
-            else: GET_VAR 'tmp0_elvis_lhs: String?' type=kotlin.String? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: GET_VAR 'tmp0_elvis_lhs: String?' type=kotlin.String? origin=null
   FUN public fun test3(a: kotlin.Any?, b: kotlin.Any?): kotlin.String
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.String
             GET_VAR 'value-parameter b: Any?' type=kotlin.Any? origin=null
           then: RETURN type=kotlin.Nothing from='test3(Any?, Any?): String'
             CONST String type=kotlin.String value=''
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.String?
             GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
           then: RETURN type=kotlin.Nothing from='test3(Any?, Any?): String'
@@ -52,12 +60,15 @@ FILE /elvis.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.Any?
             GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
           WHEN type=kotlin.String origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: TYPE_OP origin=IMPLICIT_CAST typeOperand=kotlin.String
                 GET_VAR 'value-parameter b: Any?' type=kotlin.Any? origin=null
-            else: TYPE_OP origin=IMPLICIT_CAST typeOperand=kotlin.String
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: TYPE_OP origin=IMPLICIT_CAST typeOperand=kotlin.String
                 GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
   FUN public fun test4(x: kotlin.Any): kotlin.Any
     BLOCK_BODY
@@ -66,11 +77,14 @@ FILE /elvis.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.Any?
             CALL '<get-p>(): Any?' type=kotlin.Any? origin=GET_PROPERTY
           WHEN type=kotlin.Any origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
-            else: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
   FUN public fun test5(x: kotlin.Any): kotlin.Any
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test5(Any): Any'
@@ -78,8 +92,11 @@ FILE /elvis.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_elvis_lhs: kotlin.Any?
             CALL 'foo(): Any?' type=kotlin.Any? origin=null
           WHEN type=kotlin.Any origin=null
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
-            else: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: GET_VAR 'tmp0_elvis_lhs: Any?' type=kotlin.Any? origin=null

compiler/testData/ir/irText/expressions/ifElseIf.txt

@@ -3,14 +3,18 @@ FILE /ifElseIf.kt
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test(Int): Int'
         WHEN type=kotlin.Int origin=WHEN
+          BRANCH
             if: CALL 'GT0(Int): Boolean' type=kotlin.Boolean origin=GT
               arg0: CALL 'compareTo(Int): Int' type=kotlin.Int origin=GT
                 $this: GET_VAR 'value-parameter i: Int' type=kotlin.Int origin=null
                 other: CONST Int type=kotlin.Int value='0'
             then: CONST Int type=kotlin.Int value='1'
+          BRANCH
             if: CALL 'LT0(Int): Boolean' type=kotlin.Boolean origin=LT
               arg0: CALL 'compareTo(Int): Int' type=kotlin.Int origin=LT
                 $this: GET_VAR 'value-parameter i: Int' type=kotlin.Int origin=null
                 other: CONST Int type=kotlin.Int value='0'
             then: CONST Int type=kotlin.Int value='-1'
-          else: CONST Int type=kotlin.Int value='0'
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CONST Int type=kotlin.Int value='0'

compiler/testData/ir/irText/expressions/jvmStaticFieldReference.txt

@@ -29,7 +29,9 @@ FILE /jvmStaticFieldReference.kt
       FIELD PROPERTY_BACKING_FIELD public final val test: kotlin.Int
         EXPRESSION_BODY
           WHEN type=kotlin.Int origin=WHEN
-            else: BLOCK type=kotlin.Int origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: BLOCK type=kotlin.Int origin=null
                 CALL 'println(String!): Unit' type=kotlin.Unit origin=null
                   $this: TYPE_OP origin=IMPLICIT_NOTNULL typeOperand=java.io.PrintStream
                     GET_FIELD 'out: PrintStream!' type=java.io.PrintStream! origin=GET_PROPERTY

compiler/testData/ir/irText/expressions/safeAssignment.txt

@@ -24,11 +24,14 @@ FILE /safeAssignment.kt
         VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: C?
           GET_VAR 'value-parameter nc: C?' type=C? origin=null
         WHEN type=kotlin.Unit origin=SAFE_CALL
+          BRANCH
             if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'tmp0_safe_receiver: C?' type=C? origin=null
               arg1: CONST Null type=kotlin.Nothing? value='null'
             then: TYPE_OP origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
               CONST Null type=kotlin.Nothing? value='null'
-          else: CALL '<set-x>(Int): Unit' type=kotlin.Unit origin=EQ
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CALL '<set-x>(Int): Unit' type=kotlin.Unit origin=EQ
               $this: GET_VAR 'tmp0_safe_receiver: C?' type=C? origin=null
               <set-?>: CONST Int type=kotlin.Int value='42'

compiler/testData/ir/irText/expressions/safeCallWithIncrementDecrement.txt

@@ -18,11 +18,14 @@ FILE /safeCallWithIncrementDecrement.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.Int?
             $RECEIVER of 'inc() on Int?: Int?' type=kotlin.Int?
           WHEN type=kotlin.Int? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: Int?' type=kotlin.Int? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'inc(): Int' type=kotlin.Int origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'inc(): Int' type=kotlin.Int origin=null
                 $this: GET_VAR 'tmp0_safe_receiver: Int?' type=kotlin.Int? origin=null
   FUN public operator fun kotlin.Int?.get(index: kotlin.Int): kotlin.Int
     BLOCK_BODY
@@ -36,12 +39,15 @@ FILE /safeCallWithIncrementDecrement.kt
         VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: test.C?
           GET_VAR 'value-parameter nc: C?' type=test.C? origin=null
         WHEN type=kotlin.Unit origin=SAFE_CALL
+          BRANCH
             if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'tmp0_safe_receiver: C?' type=test.C? origin=null
               arg1: CONST Null type=kotlin.Nothing? value='null'
             then: TYPE_OP origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
               CONST Null type=kotlin.Nothing? value='null'
-          else: TYPE_OP origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: TYPE_OP origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
               BLOCK type=kotlin.Int origin=POSTFIX_INCR
                 VAR IR_TEMPORARY_VARIABLE val tmp1_this: test.C?
                   GET_VAR 'tmp0_safe_receiver: C?' type=test.C? origin=null
@@ -63,11 +69,14 @@ FILE /safeCallWithIncrementDecrement.kt
               VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: test.C?
                 GET_VAR 'value-parameter nc: C?' type=test.C? origin=null
               WHEN type=kotlin.Int? origin=SAFE_CALL
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_safe_receiver: C?' type=test.C? origin=null
                     arg1: CONST Null type=kotlin.Nothing? value='null'
                   then: CONST Null type=kotlin.Nothing? value='null'
-                else: CALL '<get-p>() on C?: Int' type=kotlin.Int origin=GET_PROPERTY
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL '<get-p>() on C?: Int' type=kotlin.Int origin=GET_PROPERTY
                     $this: GET_VAR 'tmp0_safe_receiver: C?' type=test.C? origin=null
           VAR IR_TEMPORARY_VARIABLE val tmp4_index0: kotlin.Int
             CONST Int type=kotlin.Int value='0'

compiler/testData/ir/irText/expressions/safeCalls.txt

@@ -31,11 +31,14 @@ FILE /safeCalls.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.String?
             GET_VAR 'value-parameter x: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.Int? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL '<get-length>(): Int' type=kotlin.Int origin=GET_PROPERTY
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL '<get-length>(): Int' type=kotlin.Int origin=GET_PROPERTY
                 $this: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
   FUN public fun test2(x: kotlin.String?): kotlin.Int?
     BLOCK_BODY
@@ -44,11 +47,14 @@ FILE /safeCalls.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.String?
             GET_VAR 'value-parameter x: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.Int? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'hashCode(): Int' type=kotlin.Int origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'hashCode(): Int' type=kotlin.Int origin=null
                 $this: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
   FUN public fun test3(x: kotlin.String?, y: kotlin.Any?): kotlin.Boolean?
     BLOCK_BODY
@@ -57,11 +63,14 @@ FILE /safeCalls.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.String?
             GET_VAR 'value-parameter x: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.Boolean? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'equals(Any?): Boolean' type=kotlin.Boolean origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'equals(Any?): Boolean' type=kotlin.Boolean origin=null
                 $this: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                 other: GET_VAR 'value-parameter y: Any?' type=kotlin.Any? origin=null
   FUN public fun test4(x: Ref?): kotlin.Unit
@@ -70,12 +79,15 @@ FILE /safeCalls.kt
         VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: Ref?
           GET_VAR 'value-parameter x: Ref?' type=Ref? origin=null
         WHEN type=kotlin.Unit origin=SAFE_CALL
+          BRANCH
             if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'tmp0_safe_receiver: Ref?' type=Ref? origin=null
               arg1: CONST Null type=kotlin.Nothing? value='null'
             then: TYPE_OP origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
               CONST Null type=kotlin.Nothing? value='null'
-          else: CALL '<set-value>(Int): Unit' type=kotlin.Unit origin=EQ
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CALL '<set-value>(Int): Unit' type=kotlin.Unit origin=EQ
               $this: GET_VAR 'tmp0_safe_receiver: Ref?' type=Ref? origin=null
               <set-?>: CONST Int type=kotlin.Int value='0'
   FUN public fun IHost.test5(s: kotlin.String?): kotlin.Int?
@@ -85,10 +97,13 @@ FILE /safeCalls.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.String?
             GET_VAR 'value-parameter s: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.Int? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'extLength() on String: Int' type=kotlin.Int origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'extLength() on String: Int' type=kotlin.Int origin=null
                 $this: $RECEIVER of 'test5(String?) on IHost: Int?' type=IHost
                 $receiver: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null

compiler/testData/ir/irText/expressions/setFieldWithImplicitCast.txt

@@ -6,7 +6,8 @@ FILE /Derived.kt
         INSTANCE_INITIALIZER_CALL classDescriptor='Derived'
     FUN public final fun setValue(v: kotlin.Any): kotlin.Unit
       BLOCK_BODY
-        WHEN type=kotlin.Unit origin=IF
+        WHEN type=kotlin.Unit origin=null
+          BRANCH
             if: TYPE_OP origin=INSTANCEOF typeOperand=kotlin.String
               GET_VAR 'value-parameter v: Any' type=kotlin.Any origin=null
             then: BLOCK type=kotlin.Unit origin=null

compiler/testData/ir/irText/expressions/smartCasts.txt

@@ -13,7 +13,8 @@ FILE /smartCasts.kt
         GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
   FUN public fun test1(x: kotlin.Any): kotlin.Unit
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.String
             GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
           then: RETURN type=kotlin.Nothing from='test1(Any): Unit'
@@ -34,7 +35,8 @@ FILE /smartCasts.kt
             GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
   FUN public fun test2(x: kotlin.Any): kotlin.String
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.String
             GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
           then: RETURN type=kotlin.Nothing from='test2(Any): String'
@@ -45,7 +47,8 @@ FILE /smartCasts.kt
             GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
   FUN public fun test3(x: kotlin.Any): kotlin.String
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.String
             GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
           then: RETURN type=kotlin.Nothing from='test3(Any): String'

compiler/testData/ir/irText/expressions/smartCastsWithDestructuring.txt

@@ -11,7 +11,8 @@ FILE /smartCastsWithDestructuring.kt
         CONST String type=kotlin.String value=''
   FUN public fun test(x: I1): kotlin.Unit
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=I2
             GET_VAR 'value-parameter x: I1' type=I1 origin=null
           then: RETURN type=kotlin.Nothing from='test(I1): Unit'

compiler/testData/ir/irText/expressions/throw.txt

@@ -5,7 +5,8 @@ FILE /throw.kt
         CALL 'constructor Throwable()' type=kotlin.Throwable origin=null
   FUN public fun testImplicitCast(a: kotlin.Any): kotlin.Unit
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=INSTANCEOF typeOperand=kotlin.Throwable
             GET_VAR 'value-parameter a: Any' type=kotlin.Any origin=null
           then: BLOCK type=kotlin.Nothing origin=null

compiler/testData/ir/irText/expressions/tryCatchWithImplicitCast.txt

@@ -1,7 +1,8 @@
 FILE /tryCatchWithImplicitCast.kt
   FUN public fun testImplicitCast(a: kotlin.Any): kotlin.Unit
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.String
             GET_VAR 'value-parameter a: Any' type=kotlin.Any origin=null
           then: RETURN type=kotlin.Nothing from='testImplicitCast(Any): Unit'

compiler/testData/ir/irText/expressions/typeArguments.txt

@@ -3,10 +3,13 @@ FILE /typeArguments.kt
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test1(Any): Boolean'
         WHEN type=kotlin.Boolean origin=ANDAND
+          BRANCH
             if: TYPE_OP origin=INSTANCEOF typeOperand=kotlin.Array<*>
               GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
             then: CALL 'isArrayOf() on Array<*>: Boolean' type=kotlin.Boolean origin=null
               <reified T : Any>: String
               $receiver: TYPE_OP origin=IMPLICIT_CAST typeOperand=kotlin.Array<*>
                 GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
-          else: CONST Boolean type=kotlin.Boolean value='false'
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CONST Boolean type=kotlin.Boolean value='false'

compiler/testData/ir/irText/expressions/varargWithImplicitCast.txt

@@ -1,7 +1,8 @@
 FILE /varargWithImplicitCast.kt
   FUN public fun testScalar(a: kotlin.Any): kotlin.IntArray
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.Int
             GET_VAR 'value-parameter a: Any' type=kotlin.Any origin=null
           then: RETURN type=kotlin.Nothing from='testScalar(Any): IntArray'
@@ -13,7 +14,8 @@ FILE /varargWithImplicitCast.kt
               GET_VAR 'value-parameter a: Any' type=kotlin.Any origin=null
   FUN public fun testSpread(a: kotlin.Any): kotlin.IntArray
     BLOCK_BODY
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=NOT_INSTANCEOF typeOperand=kotlin.IntArray
             GET_VAR 'value-parameter a: Any' type=kotlin.Any origin=null
           then: RETURN type=kotlin.Nothing from='testSpread(Any): IntArray'

compiler/testData/ir/irText/expressions/variableAsFunctionCall.txt

@@ -34,16 +34,22 @@ FILE /variableAsFunctionCall.kt
               VAR IR_TEMPORARY_VARIABLE val tmp0_safe_receiver: kotlin.String?
                 GET_VAR 'value-parameter ns: String?' type=kotlin.String? origin=null
               WHEN type=(() -> kotlin.String)? origin=SAFE_CALL
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
                     arg1: CONST Null type=kotlin.Nothing? value='null'
                   then: CONST Null type=kotlin.Nothing? value='null'
-                else: CALL 'k() on String: () -> String' type=() -> kotlin.String origin=null
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL 'k() on String: () -> String' type=() -> kotlin.String origin=null
                     $this: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
           WHEN type=kotlin.String? origin=SAFE_CALL
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp1_safe_receiver: (() -> String)?' type=(() -> kotlin.String)? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST Null type=kotlin.Nothing? value='null'
-            else: CALL 'invoke(): String' type=kotlin.String origin=null
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CALL 'invoke(): String' type=kotlin.String origin=null
                 $this: GET_VAR 'tmp1_safe_receiver: (() -> String)?' type=(() -> kotlin.String)? origin=null

compiler/testData/ir/irText/expressions/when.txt

@@ -11,46 +11,58 @@ FILE /when.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_subject: kotlin.Any?
             GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
           WHEN type=kotlin.String origin=WHEN
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_subject: Any?' type=kotlin.Any? origin=null
                 arg1: CONST Null type=kotlin.Nothing? value='null'
               then: CONST String type=kotlin.String value='null'
+            BRANCH
               if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                 arg0: GET_VAR 'tmp0_subject: Any?' type=kotlin.Any? origin=null
                 arg1: GET_OBJECT 'A' type=A
               then: CONST String type=kotlin.String value='A'
+            BRANCH
               if: TYPE_OP origin=INSTANCEOF typeOperand=kotlin.String
                 GET_VAR 'tmp0_subject: Any?' type=kotlin.Any? origin=null
               then: CONST String type=kotlin.String value='String'
+            BRANCH
               if: CALL 'contains(Any) on Iterable<Any>: Boolean' type=kotlin.Boolean origin=IN
                 <T>: Any
                 $receiver: CALL 'setOf(): Set<Nothing>' type=kotlin.collections.Set<kotlin.Nothing> origin=null
                   <T>: Nothing
                 element: GET_VAR 'tmp0_subject: Any?' type=kotlin.Any? origin=null
               then: CONST String type=kotlin.String value='nothingness?'
-            else: CONST String type=kotlin.String value='something'
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CONST String type=kotlin.String value='something'
   FUN public fun test(x: kotlin.Any?): kotlin.String
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test(Any?): String'
         WHEN type=kotlin.String origin=WHEN
+          BRANCH
             if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
               arg1: CONST Null type=kotlin.Nothing? value='null'
             then: CONST String type=kotlin.String value='null'
+          BRANCH
             if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
               arg1: GET_OBJECT 'A' type=A
             then: CONST String type=kotlin.String value='A'
+          BRANCH
             if: TYPE_OP origin=INSTANCEOF typeOperand=kotlin.String
               GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
             then: CONST String type=kotlin.String value='String'
+          BRANCH
             if: CALL 'contains(Any) on Iterable<Any>: Boolean' type=kotlin.Boolean origin=IN
               <T>: Any
               $receiver: CALL 'setOf(): Set<Nothing>' type=kotlin.collections.Set<kotlin.Nothing> origin=null
                 <T>: Nothing
               element: GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
             then: CONST String type=kotlin.String value='nothingness?'
-          else: CONST String type=kotlin.String value='something'
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CONST String type=kotlin.String value='something'
   FUN public fun testComma(x: kotlin.Int): kotlin.String
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='testComma(Int): String'
@@ -58,46 +70,69 @@ FILE /when.kt
           VAR IR_TEMPORARY_VARIABLE val tmp0_subject: kotlin.Int
             GET_VAR 'value-parameter x: Int' type=kotlin.Int origin=null
           WHEN type=kotlin.String origin=WHEN
+            BRANCH
               if: WHEN type=kotlin.Boolean origin=WHEN_COMMA
+                BRANCH
                   if: WHEN type=kotlin.Boolean origin=WHEN_COMMA
+                    BRANCH
                       if: WHEN type=kotlin.Boolean origin=WHEN_COMMA
+                        BRANCH
                           if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                             arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                             arg1: CONST Int type=kotlin.Int value='1'
                           then: CONST Boolean type=kotlin.Boolean value='true'
-                  else: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
+                        BRANCH
+                          if: CONST Boolean type=kotlin.Boolean value='true'
+                          then: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                             arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                             arg1: CONST Int type=kotlin.Int value='2'
                       then: CONST Boolean type=kotlin.Boolean value='true'
-                else: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
+                    BRANCH
+                      if: CONST Boolean type=kotlin.Boolean value='true'
+                      then: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                         arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                         arg1: CONST Int type=kotlin.Int value='3'
                   then: CONST Boolean type=kotlin.Boolean value='true'
-              else: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                     arg1: CONST Int type=kotlin.Int value='4'
               then: CONST String type=kotlin.String value='1234'
+            BRANCH
               if: WHEN type=kotlin.Boolean origin=WHEN_COMMA
+                BRANCH
                   if: WHEN type=kotlin.Boolean origin=WHEN_COMMA
+                    BRANCH
                       if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                         arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                         arg1: CONST Int type=kotlin.Int value='5'
                       then: CONST Boolean type=kotlin.Boolean value='true'
-                else: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
+                    BRANCH
+                      if: CONST Boolean type=kotlin.Boolean value='true'
+                      then: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                         arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                         arg1: CONST Int type=kotlin.Int value='6'
                   then: CONST Boolean type=kotlin.Boolean value='true'
-              else: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                     arg1: CONST Int type=kotlin.Int value='7'
               then: CONST String type=kotlin.String value='567'
+            BRANCH
               if: WHEN type=kotlin.Boolean origin=WHEN_COMMA
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                     arg1: CONST Int type=kotlin.Int value='8'
                   then: CONST Boolean type=kotlin.Boolean value='true'
-              else: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
+                BRANCH
+                  if: CONST Boolean type=kotlin.Boolean value='true'
+                  then: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp0_subject: Int' type=kotlin.Int origin=null
                     arg1: CONST Int type=kotlin.Int value='9'
               then: CONST String type=kotlin.String value='89'
-            else: CONST String type=kotlin.String value='?'
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value='true'
+              then: CONST String type=kotlin.String value='?'

compiler/testData/ir/irText/expressions/whenElse.txt

@@ -3,4 +3,6 @@ FILE /whenElse.kt
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test(): Int'
         WHEN type=kotlin.Int origin=WHEN
-          else: CONST Int type=kotlin.Int value='42'
+          BRANCH
+            if: CONST Boolean type=kotlin.Boolean value='true'
+            then: CONST Int type=kotlin.Int value='42'

compiler/testData/ir/irText/expressions/whileDoWhile.txt

@@ -71,7 +71,8 @@ FILE /whileDoWhile.kt
     BLOCK_BODY
       VAR val a: kotlin.Any? = null
         CONST Null type=kotlin.Nothing? value='null'
-      WHEN type=kotlin.Unit origin=IF
+      WHEN type=kotlin.Unit origin=null
+        BRANCH
           if: TYPE_OP origin=INSTANCEOF typeOperand=kotlin.Boolean
             GET_VAR 'a: Any?' type=kotlin.Any? origin=null
           then: BLOCK type=kotlin.Unit origin=null

compiler/testData/ir/irText/lambdas/nonLocalReturn.txt

@@ -34,7 +34,8 @@ FILE /nonLocalReturn.kt
         action: BLOCK type=(kotlin.Int) -> kotlin.Unit origin=LAMBDA
           FUN LOCAL_FUNCTION_FOR_LAMBDA local final fun <anonymous>(it: kotlin.Int): kotlin.Unit
             BLOCK_BODY
-              WHEN type=kotlin.Unit origin=IF
+              WHEN type=kotlin.Unit origin=null
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'value-parameter it: Int' type=kotlin.Int origin=null
                     arg1: CONST Int type=kotlin.Int value='0'
@@ -51,7 +52,8 @@ FILE /nonLocalReturn.kt
         action: BLOCK type=(kotlin.Int) -> kotlin.Unit origin=LAMBDA
           FUN LOCAL_FUNCTION_FOR_LAMBDA local final fun <anonymous>(it: kotlin.Int): kotlin.Unit
             BLOCK_BODY
-              WHEN type=kotlin.Unit origin=IF
+              WHEN type=kotlin.Unit origin=null
+                BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'value-parameter it: Int' type=kotlin.Int origin=null
                     arg1: CONST Int type=kotlin.Int value='0'

compiler/testData/ir/irText/regressions/coercionInLoop.txt

@@ -14,7 +14,8 @@ FILE /coercionInLoop.kt
           $this: GET_VAR 'x: DoubleIterator' type=kotlin.collections.DoubleIterator origin=null
         body: TYPE_OP origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
           BLOCK type=kotlin.Int origin=null
-            WHEN type=kotlin.Unit origin=IF
+            WHEN type=kotlin.Unit origin=null
+              BRANCH
                 if: CALL 'NOT(Boolean): Boolean' type=kotlin.Boolean origin=EXCLEQ
                   arg0: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EXCLEQ
                     arg0: CALL 'get(Int): Double' type=kotlin.Double origin=GET_ARRAY_ELEMENT