From 2bfce4f127ef3952d286e186baddaa737d783095 Mon Sep 17 00:00:00 2001
From: Mikhail Glukhikh <mikhail.glukhikh@jetbrains.com>
Date: Tue, 11 Feb 2020 16:28:29 +0300
Subject: [PATCH] FIR2IR: provide correct origins for 'for' loops

---
 .../fir/backend/Fir2IrDeclarationStorage.kt   | 10 ++-
 .../kotlin/fir/backend/Fir2IrVisitor.kt       | 47 ++++++++----
 .../kotlin/fir/resolve/ResolveUtils.kt        | 10 ++-
 .../expressions/badBreakContinue.fir.txt      |  8 +-
 .../irText/expressions/breakContinue.fir.txt  | 12 +--
 .../breakContinueInLoopHeader.fir.txt         | 38 +++++-----
 .../expressions/breakContinueInWhen.fir.txt   | 20 ++---
 .../withVarargViewedAsArray.fir.txt           | 10 +--
 .../ir/irText/expressions/for.fir.txt         | 54 +++++++-------
 .../expressions/forWithBreakContinue.fir.txt  | 72 +++++++++---------
 .../forWithImplicitReceivers.fir.txt          |  4 +-
 .../irText/expressions/whileDoWhile.fir.txt   |  6 +-
 .../irText/regressions/coercionInLoop.fir.txt |  2 +-
 .../enhancedNullabilityInForLoop.fir.txt      | 74 +++++++++----------
 14 files changed, 198 insertions(+), 169 deletions(-)

diff --git a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt
index bc6a8279447..34e236c15e4 100644
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrDeclarationStorage.kt
@@ -779,11 +779,15 @@ class Fir2IrDeclarationStorage(
         }
     }
 
-    fun createAndSaveIrVariable(variable: FirVariable<*>): IrVariable {
+    fun createAndSaveIrVariable(variable: FirVariable<*>, givenOrigin: IrDeclarationOrigin? = null): IrVariable {
         val type = variable.returnTypeRef.toIrType(session, this)
         // Some temporary variables are produced in RawFirBuilder, but we consistently use special names for them.
-        val origin =
-            if (variable.name.isSpecial) IrDeclarationOrigin.IR_TEMPORARY_VARIABLE else IrDeclarationOrigin.DEFINED
+        val origin = when {
+            givenOrigin != null -> givenOrigin
+            variable.name == Name.special("<iterator>") -> IrDeclarationOrigin.FOR_LOOP_ITERATOR
+            variable.name.isSpecial -> IrDeclarationOrigin.IR_TEMPORARY_VARIABLE
+            else -> IrDeclarationOrigin.DEFINED
+        }
         val irVariable = variable.convertWithOffsets { startOffset, endOffset ->
             declareIrVariable(
                 startOffset, endOffset, origin,
diff --git a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
index 7841ccb4718..15d20ed6aeb 100644
--- a/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
+++ b/compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/backend/Fir2IrVisitor.kt
@@ -469,9 +469,14 @@ class Fir2IrVisitor(
 
     private fun visitLocalVariable(variable: FirProperty): IrElement {
         assert(variable.isLocal)
-        val irVariable = declarationStorage.createAndSaveIrVariable(variable)
+        val initializer = variable.initializer
+        val isNextVariable = initializer is FirFunctionCall &&
+                initializer.resolvedNamedFunctionSymbol()?.callableId?.isIteratorNext() == true &&
+                variable.source.psi?.parent is KtForExpression
+        val irVariable = declarationStorage.createAndSaveIrVariable(
+            variable, if (isNextVariable) IrDeclarationOrigin.FOR_LOOP_VARIABLE else null
+        )
         return irVariable.setParentByParentStack().apply {
-            val initializer = variable.initializer
             if (initializer != null) {
                 this.initializer = initializer.toIrExpression()
             }
@@ -671,7 +676,13 @@ class Fir2IrVisitor(
             is FirPropertyFromParameterResolvedNamedReference -> IrStatementOrigin.INITIALIZE_PROPERTY_FROM_PARAMETER
             is FirResolvedNamedReference -> when (resolvedSymbol) {
                 is AccessorSymbol, is SyntheticPropertySymbol -> IrStatementOrigin.GET_PROPERTY
-                is FirNamedFunctionSymbol -> if (resolvedSymbol.callableId.isInvoke()) IrStatementOrigin.INVOKE else null
+                is FirNamedFunctionSymbol -> when {
+                    resolvedSymbol.callableId.isInvoke() -> IrStatementOrigin.INVOKE
+                    source.psi is KtForExpression && resolvedSymbol.callableId.isIteratorNext() -> IrStatementOrigin.FOR_LOOP_NEXT
+                    source.psi is KtForExpression && resolvedSymbol.callableId.isIteratorHasNext() -> IrStatementOrigin.FOR_LOOP_HAS_NEXT
+                    source.psi is KtForExpression && resolvedSymbol.callableId.isIterator() -> IrStatementOrigin.FOR_LOOP_ITERATOR
+                    else -> null
+                }
                 else -> null
             }
             else -> null
@@ -857,16 +868,24 @@ class Fir2IrVisitor(
         val convertibleCall = if (functionCall.toResolvedCallableSymbol()?.fir is FirIntegerOperator) {
             functionCall.copy().transformSingle(integerApproximator, null)
         } else {
-            functionCall.replaceCalleeReferenceWithOverridden()
+            val resolvedSymbol = functionCall.resolvedNamedFunctionSymbol()
+            if (resolvedSymbol != null) {
+                functionCall.replaceCalleeReferenceWithOverridden(resolvedSymbol)
+            } else {
+                functionCall
+            }
         }
         return convertibleCall.toIrExpression(convertibleCall.typeRef)
             .applyCallArguments(convertibleCall).applyTypeArguments(convertibleCall).applyReceivers(convertibleCall)
     }
 
+    private fun FirFunctionCall.resolvedNamedFunctionSymbol(): FirNamedFunctionSymbol? {
+        val calleeReference = (calleeReference as? FirResolvedNamedReference) ?: return null
+        return calleeReference.resolvedSymbol as? FirNamedFunctionSymbol
+    }
+
     // Use the generic invoke & next methods to match bridges generated by the backend.
-    private fun FirFunctionCall.replaceCalleeReferenceWithOverridden(): FirFunctionCall {
-        val calleeReference = (calleeReference as? FirResolvedNamedReference) ?: return this
-        val resolvedSymbol = (calleeReference.resolvedSymbol as? FirNamedFunctionSymbol) ?: return this
+    private fun FirFunctionCall.replaceCalleeReferenceWithOverridden(resolvedSymbol: FirNamedFunctionSymbol): FirFunctionCall {
         val overriddenSymbol = resolvedSymbol.overriddenSymbol ?: return this
         if (resolvedSymbol.callableId.isInvoke() || resolvedSymbol.callableId.isIteratorNext()) {
             return copy(
@@ -1090,7 +1109,7 @@ class Fir2IrVisitor(
         }
     }
 
-    private fun FirBlock.convertToIrExpressionOrBlock(): IrExpression {
+    private fun FirBlock.convertToIrExpressionOrBlock(origin: IrStatementOrigin? = null): IrExpression {
         if (statements.size == 1) {
             val firStatement = statements.single()
             if (firStatement is FirExpression) {
@@ -1101,7 +1120,7 @@ class Fir2IrVisitor(
             (statements.lastOrNull() as? FirExpression)?.typeRef?.toIrType(this@Fir2IrVisitor.session, declarationStorage) ?: unitType
         return convertWithOffsets { startOffset, endOffset ->
             IrBlockImpl(
-                startOffset, endOffset, type, null,
+                startOffset, endOffset, type, origin,
                 statements.mapNotNull { it.toIrStatement() }
             )
         }
@@ -1204,15 +1223,13 @@ class Fir2IrVisitor(
 
     override fun visitWhileLoop(whileLoop: FirWhileLoop, data: Any?): IrElement {
         return whileLoop.convertWithOffsets { startOffset, endOffset ->
-            IrWhileLoopImpl(
-                startOffset, endOffset, unitType,
-                if (whileLoop.psi is KtForExpression) IrStatementOrigin.FOR_LOOP_INNER_WHILE
-                else IrStatementOrigin.WHILE_LOOP
-            ).apply {
+            val origin = if (whileLoop.psi is KtForExpression) IrStatementOrigin.FOR_LOOP_INNER_WHILE
+            else IrStatementOrigin.WHILE_LOOP
+            IrWhileLoopImpl(startOffset, endOffset, unitType, origin).apply {
                 loopMap[whileLoop] = this
                 label = whileLoop.label?.name
                 condition = whileLoop.condition.toIrExpression()
-                body = whileLoop.block.convertToIrExpressionOrBlock()
+                body = whileLoop.block.convertToIrExpressionOrBlock(origin)
                 loopMap.remove(whileLoop)
             }
         }
diff --git a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ResolveUtils.kt b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ResolveUtils.kt
index e9b0a438789..8ce06ec6c4e 100644
--- a/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ResolveUtils.kt
+++ b/compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/ResolveUtils.kt
@@ -483,4 +483,12 @@ fun CallableId.isKFunctionInvoke() =
             && packageName.asString() == "kotlin.reflect"
 
 fun CallableId.isIteratorNext() =
-    callableName.asString() == "next" && className?.asString()?.equals("Iterator") == true && packageName.asString() == "kotlin.collections"
+    callableName.asString() == "next" && className?.asString()?.endsWith("Iterator") == true
+            && packageName.asString() == "kotlin.collections"
+
+fun CallableId.isIteratorHasNext() =
+    callableName.asString() == "hasNext" && className?.asString()?.endsWith("Iterator") == true
+            && packageName.asString() == "kotlin.collections"
+
+fun CallableId.isIterator() =
+    callableName.asString() == "iterator" && packageName.asString() == "kotlin.collections"
diff --git a/compiler/testData/ir/irText/expressions/badBreakContinue.fir.txt b/compiler/testData/ir/irText/expressions/badBreakContinue.fir.txt
index 4861247b5ec..6646171c5e2 100644
--- a/compiler/testData/ir/irText/expressions/badBreakContinue.fir.txt
+++ b/compiler/testData/ir/irText/expressions/badBreakContinue.fir.txt
@@ -7,14 +7,14 @@ FILE fqName:<root> fileName:/badBreakContinue.kt
     BLOCK_BODY
       WHILE label=L1 origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Nothing origin=null
+        body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
           ERROR_EXPR 'Unbound loop: break@@@[ERROR_EXPR(Cannot bind label ERROR to a loop)] ' type=kotlin.Nothing
           ERROR_EXPR 'Unbound loop: continue@@@[ERROR_EXPR(Cannot bind label ERROR to a loop)] ' type=kotlin.Nothing
   FUN name:test3 visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
       WHILE label=L1 origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
           VAR name:lambda type:kotlin.Function0<kotlin.Nothing> [val]
             FUN_EXPR type=kotlin.Function0<kotlin.Nothing> origin=LAMBDA
               FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> () returnType:kotlin.Nothing
@@ -25,7 +25,7 @@ FILE fqName:<root> fileName:/badBreakContinue.kt
     BLOCK_BODY
       WHILE label=null origin=WHILE_LOOP
         condition: ERROR_EXPR 'Unbound loop: break@@@[ERROR_EXPR(Cannot bind unlabeled jump to a loop)] ' type=kotlin.Nothing
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
       WHILE label=null origin=WHILE_LOOP
         condition: ERROR_EXPR 'Unbound loop: continue@@@[ERROR_EXPR(Cannot bind unlabeled jump to a loop)] ' type=kotlin.Nothing
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
diff --git a/compiler/testData/ir/irText/expressions/breakContinue.fir.txt b/compiler/testData/ir/irText/expressions/breakContinue.fir.txt
index dfd2a27515b..52bbb3be4fe 100644
--- a/compiler/testData/ir/irText/expressions/breakContinue.fir.txt
+++ b/compiler/testData/ir/irText/expressions/breakContinue.fir.txt
@@ -17,19 +17,19 @@ FILE fqName:<root> fileName:/breakContinue.kt
     BLOCK_BODY
       WHILE label=OUTER origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Nothing origin=null
+        body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
           WHILE label=INNER origin=WHILE_LOOP
             condition: CONST Boolean type=kotlin.Boolean value=true
-            body: BLOCK type=kotlin.Nothing origin=null
+            body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
               BREAK label=INNER loop.label=INNER
               BREAK label=OUTER loop.label=OUTER
           BREAK label=OUTER loop.label=OUTER
       WHILE label=OUTER origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Nothing origin=null
+        body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
           WHILE label=INNER origin=WHILE_LOOP
             condition: CONST Boolean type=kotlin.Boolean value=true
-            body: BLOCK type=kotlin.Nothing origin=null
+            body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
               CONTINUE label=INNER loop.label=INNER
               CONTINUE label=OUTER loop.label=OUTER
           CONTINUE label=OUTER loop.label=OUTER
@@ -37,14 +37,14 @@ FILE fqName:<root> fileName:/breakContinue.kt
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Nothing origin=null
+        body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
           WHILE label=L origin=WHILE_LOOP
             condition: CONST Boolean type=kotlin.Boolean value=true
             body: BREAK label=L loop.label=L
           BREAK label=L loop.label=L
       WHILE label=L origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Nothing origin=null
+        body: BLOCK type=kotlin.Nothing origin=WHILE_LOOP
           WHILE label=L origin=WHILE_LOOP
             condition: CONST Boolean type=kotlin.Boolean value=true
             body: CONTINUE label=L loop.label=L
diff --git a/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.fir.txt b/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.fir.txt
index 5c7459bbe9f..ae02a836b6f 100644
--- a/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.fir.txt
+++ b/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.fir.txt
@@ -4,7 +4,7 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
           WHILE label=L2 origin=WHILE_LOOP
             condition: BLOCK type=kotlin.Boolean origin=ELVIS
               VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.Boolean? [val]
@@ -19,13 +19,13 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                   if: CONST Boolean type=kotlin.Boolean value=true
                   then: TYPE_OP type=kotlin.Boolean origin=IMPLICIT_CAST typeOperand=kotlin.Boolean
                     GET_VAR 'val tmp_0: kotlin.Boolean? [val] declared in <root>.test1' type=kotlin.Boolean? origin=null
-            body: BLOCK type=kotlin.Unit origin=null
+            body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
   FUN name:test2 visibility:public modality:FINAL <> (c:kotlin.Boolean?) returnType:kotlin.Unit
     VALUE_PARAMETER name:c index:0 type:kotlin.Boolean?
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
           WHILE label=L2 origin=WHILE_LOOP
             condition: BLOCK type=kotlin.Boolean origin=ELVIS
               VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.Boolean? [val]
@@ -40,15 +40,15 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                   if: CONST Boolean type=kotlin.Boolean value=true
                   then: TYPE_OP type=kotlin.Boolean origin=IMPLICIT_CAST typeOperand=kotlin.Boolean
                     GET_VAR 'val tmp_1: kotlin.Boolean? [val] declared in <root>.test2' type=kotlin.Boolean? origin=null
-            body: BLOCK type=kotlin.Unit origin=null
+            body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
   FUN name:test3 visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>?) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>?
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR IR_TEMPORARY_VARIABLE name:tmp_2 type:kotlin.collections.Iterator<kotlin.String> [val]
-            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
+          VAR FOR_LOOP_ITERATOR name:tmp_2 type:kotlin.collections.Iterator<kotlin.String> [val]
+            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
               $this: BLOCK type=kotlin.collections.List<kotlin.String> origin=ELVIS
                 VAR IR_TEMPORARY_VARIABLE name:tmp_3 type:kotlin.collections.List<kotlin.String>? [val]
                   GET_VAR 'ss: kotlin.collections.List<kotlin.String>? declared in <root>.test3' type=kotlin.collections.List<kotlin.String>? origin=null
@@ -63,20 +63,20 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                     then: TYPE_OP type=kotlin.collections.List<kotlin.String> origin=IMPLICIT_CAST typeOperand=kotlin.collections.List<kotlin.String>
                       GET_VAR 'val tmp_3: kotlin.collections.List<kotlin.String>? [val] declared in <root>.test3' type=kotlin.collections.List<kotlin.String>? origin=null
           WHILE label=L2 origin=FOR_LOOP_INNER_WHILE
-            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
               $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.test3' type=kotlin.collections.Iterator<kotlin.String> origin=null
-            body: BLOCK type=kotlin.Unit origin=null
-              VAR name:s type:kotlin.String [val]
-                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+            body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+              VAR FOR_LOOP_VARIABLE name:s type:kotlin.String [val]
+                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
                   $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.test3' type=kotlin.collections.Iterator<kotlin.String> origin=null
   FUN name:test4 visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>?) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>?
     BLOCK_BODY
       WHILE label=L origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR IR_TEMPORARY_VARIABLE name:tmp_4 type:kotlin.collections.Iterator<kotlin.String> [val]
-            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
+          VAR FOR_LOOP_ITERATOR name:tmp_4 type:kotlin.collections.Iterator<kotlin.String> [val]
+            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
               $this: BLOCK type=kotlin.collections.List<kotlin.String> origin=ELVIS
                 VAR IR_TEMPORARY_VARIABLE name:tmp_5 type:kotlin.collections.List<kotlin.String>? [val]
                   GET_VAR 'ss: kotlin.collections.List<kotlin.String>? declared in <root>.test4' type=kotlin.collections.List<kotlin.String>? origin=null
@@ -91,11 +91,11 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                     then: TYPE_OP type=kotlin.collections.List<kotlin.String> origin=IMPLICIT_CAST typeOperand=kotlin.collections.List<kotlin.String>
                       GET_VAR 'val tmp_5: kotlin.collections.List<kotlin.String>? [val] declared in <root>.test4' type=kotlin.collections.List<kotlin.String>? origin=null
           WHILE label=L2 origin=FOR_LOOP_INNER_WHILE
-            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
               $this: GET_VAR 'val tmp_4: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.test4' type=kotlin.collections.Iterator<kotlin.String> origin=null
-            body: BLOCK type=kotlin.Unit origin=null
-              VAR name:s type:kotlin.String [val]
-                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+            body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+              VAR FOR_LOOP_VARIABLE name:s type:kotlin.String [val]
+                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
                   $this: GET_VAR 'val tmp_4: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.test4' type=kotlin.collections.Iterator<kotlin.String> origin=null
   FUN name:test5 visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
@@ -103,7 +103,7 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
         CONST Int type=kotlin.Int value=0
       WHILE label=Outer origin=WHILE_LOOP
         condition: CONST Boolean type=kotlin.Boolean value=true
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
           VAR IR_TEMPORARY_VARIABLE name:tmp_6 type:kotlin.Int [val]
             GET_VAR 'var i: kotlin.Int [var] declared in <root>.test5' type=kotlin.Int origin=null
           SET_VAR 'var i: kotlin.Int [var] declared in <root>.test5' type=kotlin.Unit origin=null
diff --git a/compiler/testData/ir/irText/expressions/breakContinueInWhen.fir.txt b/compiler/testData/ir/irText/expressions/breakContinueInWhen.fir.txt
index efc823eb4b2..3f64cf210c9 100644
--- a/compiler/testData/ir/irText/expressions/breakContinueInWhen.fir.txt
+++ b/compiler/testData/ir/irText/expressions/breakContinueInWhen.fir.txt
@@ -12,15 +12,15 @@ FILE fqName:<root> fileName:/breakContinueInWhen.kt
                   GET_VAR 'i: kotlin.Int declared in <root>.testBreakFor.<anonymous>' type=kotlin.Int origin=null
       VAR name:k type:kotlin.Int [var]
         CONST Int type=kotlin.Int value=0
-      VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.collections.IntIterator [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_0 type:kotlin.collections.IntIterator [val]
         CALL 'public final fun iterator (): kotlin.collections.IntIterator [operator] declared in kotlin.IntArray' type=kotlin.collections.IntIterator origin=null
           $this: GET_VAR 'val xs: kotlin.IntArray [val] declared in <root>.testBreakFor' type=kotlin.IntArray origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_0: kotlin.collections.IntIterator [val] declared in <root>.testBreakFor' type=kotlin.collections.IntIterator origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:x type:kotlin.Int [val]
-            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:x type:kotlin.Int [val]
+            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_0: kotlin.collections.IntIterator [val] declared in <root>.testBreakFor' type=kotlin.collections.IntIterator origin=null
           WHEN type=kotlin.Unit origin=WHEN
             BRANCH
@@ -69,15 +69,15 @@ FILE fqName:<root> fileName:/breakContinueInWhen.kt
                   GET_VAR 'i: kotlin.Int declared in <root>.testContinueFor.<anonymous>' type=kotlin.Int origin=null
       VAR name:k type:kotlin.Int [var]
         CONST Int type=kotlin.Int value=0
-      VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.collections.IntIterator [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_1 type:kotlin.collections.IntIterator [val]
         CALL 'public final fun iterator (): kotlin.collections.IntIterator [operator] declared in kotlin.IntArray' type=kotlin.collections.IntIterator origin=null
           $this: GET_VAR 'val xs: kotlin.IntArray [val] declared in <root>.testContinueFor' type=kotlin.IntArray origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_1: kotlin.collections.IntIterator [val] declared in <root>.testContinueFor' type=kotlin.collections.IntIterator origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:x type:kotlin.Int [val]
-            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:x type:kotlin.Int [val]
+            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_1: kotlin.collections.IntIterator [val] declared in <root>.testContinueFor' type=kotlin.collections.IntIterator origin=null
           WHEN type=kotlin.Unit origin=WHEN
             BRANCH
diff --git a/compiler/testData/ir/irText/expressions/callableReferences/withVarargViewedAsArray.fir.txt b/compiler/testData/ir/irText/expressions/callableReferences/withVarargViewedAsArray.fir.txt
index c7f311e91fa..a3fff390b7f 100644
--- a/compiler/testData/ir/irText/expressions/callableReferences/withVarargViewedAsArray.fir.txt
+++ b/compiler/testData/ir/irText/expressions/callableReferences/withVarargViewedAsArray.fir.txt
@@ -4,15 +4,15 @@ FILE fqName:<root> fileName:/withVarargViewedAsArray.kt
     BLOCK_BODY
       VAR name:result type:kotlin.Int [var]
         CONST Int type=kotlin.Int value=0
-      VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.collections.IntIterator [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_0 type:kotlin.collections.IntIterator [val]
         CALL 'public final fun iterator (): kotlin.collections.IntIterator [operator] declared in kotlin.IntArray' type=kotlin.collections.IntIterator origin=null
           $this: GET_VAR 'args: kotlin.IntArray [vararg] declared in <root>.sum' type=kotlin.IntArray origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_0: kotlin.collections.IntIterator [val] declared in <root>.sum' type=kotlin.collections.IntIterator origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:arg type:kotlin.Int [val]
-            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:arg type:kotlin.Int [val]
+            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_0: kotlin.collections.IntIterator [val] declared in <root>.sum' type=kotlin.collections.IntIterator origin=null
           SET_VAR 'var result: kotlin.Int [var] declared in <root>.sum' type=kotlin.Unit origin=null
             CALL 'public final fun plus (other: kotlin.Int): kotlin.Int [operator] declared in kotlin.Int' type=kotlin.Int origin=null
diff --git a/compiler/testData/ir/irText/expressions/for.fir.txt b/compiler/testData/ir/irText/expressions/for.fir.txt
index 4a4836f4a72..a091c3c19fb 100644
--- a/compiler/testData/ir/irText/expressions/for.fir.txt
+++ b/compiler/testData/ir/irText/expressions/for.fir.txt
@@ -2,65 +2,65 @@ FILE fqName:<root> fileName:/for.kt
   FUN name:testEmpty visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.collections.Iterator<kotlin.String> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_0 type:kotlin.collections.Iterator<kotlin.String> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testEmpty' type=kotlin.collections.List<kotlin.String> origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_0: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testEmpty' type=kotlin.collections.Iterator<kotlin.String> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:s type:kotlin.String [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:s type:kotlin.String [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_0: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testEmpty' type=kotlin.collections.Iterator<kotlin.String> origin=null
   FUN name:testIterable visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.collections.Iterator<kotlin.String> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_1 type:kotlin.collections.Iterator<kotlin.String> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testIterable' type=kotlin.collections.List<kotlin.String> origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_1: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testIterable' type=kotlin.collections.Iterator<kotlin.String> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:s type:kotlin.String [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:s type:kotlin.String [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_1: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testIterable' type=kotlin.collections.Iterator<kotlin.String> origin=null
           CALL 'public final fun println (message: kotlin.Any?): kotlin.Unit [inline] declared in kotlin.io' type=kotlin.Unit origin=null
             message: GET_VAR 'val s: kotlin.String [val] declared in <root>.testIterable' type=kotlin.String origin=null
   FUN name:testDestructuring visibility:public modality:FINAL <> (pp:kotlin.collections.List<kotlin.Pair<kotlin.Int, kotlin.String>>) returnType:kotlin.Unit
     VALUE_PARAMETER name:pp index:0 type:kotlin.collections.List<kotlin.Pair<kotlin.Int, kotlin.String>>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_2 type:kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_2 type:kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'pp: kotlin.collections.List<kotlin.Pair<kotlin.Int, kotlin.String>> declared in <root>.testDestructuring' type=kotlin.collections.List<kotlin.Pair<kotlin.Int, kotlin.String>> origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> [val] declared in <root>.testDestructuring' type=kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR IR_TEMPORARY_VARIABLE name:tmp_3 type:kotlin.Pair<kotlin.Int, kotlin.String> [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.Pair<kotlin.Int, kotlin.String> origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:<destruct> type:kotlin.Pair<kotlin.Int, kotlin.String> [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.Pair<kotlin.Int, kotlin.String> origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> [val] declared in <root>.testDestructuring' type=kotlin.collections.Iterator<kotlin.Pair<kotlin.Int, kotlin.String>> origin=null
           VAR name:i type:kotlin.Int [val]
             CALL 'public final fun component1 (): kotlin.Int [operator] declared in kotlin.Pair' type=kotlin.Int origin=null
-              $this: GET_VAR 'val tmp_3: kotlin.Pair<kotlin.Int, kotlin.String> [val] declared in <root>.testDestructuring' type=kotlin.Pair<kotlin.Int, kotlin.String> origin=null
+              $this: GET_VAR 'val <destruct>: kotlin.Pair<kotlin.Int, kotlin.String> [val] declared in <root>.testDestructuring' type=kotlin.Pair<kotlin.Int, kotlin.String> origin=null
           VAR name:s type:kotlin.String [val]
             CALL 'public final fun component2 (): kotlin.String [operator] declared in kotlin.Pair' type=kotlin.String origin=null
-              $this: GET_VAR 'val tmp_3: kotlin.Pair<kotlin.Int, kotlin.String> [val] declared in <root>.testDestructuring' type=kotlin.Pair<kotlin.Int, kotlin.String> origin=null
+              $this: GET_VAR 'val <destruct>: kotlin.Pair<kotlin.Int, kotlin.String> [val] declared in <root>.testDestructuring' type=kotlin.Pair<kotlin.Int, kotlin.String> origin=null
           CALL 'public final fun println (message: kotlin.Int): kotlin.Unit [inline] declared in kotlin.io' type=kotlin.Unit origin=null
             message: GET_VAR 'val i: kotlin.Int [val] declared in <root>.testDestructuring' type=kotlin.Int origin=null
           CALL 'public final fun println (message: kotlin.Any?): kotlin.Unit [inline] declared in kotlin.io' type=kotlin.Unit origin=null
             message: GET_VAR 'val s: kotlin.String [val] declared in <root>.testDestructuring' type=kotlin.String origin=null
   FUN name:testRange visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_4 type:kotlin.collections.IntIterator [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_3 type:kotlin.collections.IntIterator [val]
         CALL 'public open fun iterator (): kotlin.collections.IntIterator [operator] declared in kotlin.ranges.IntProgression' type=kotlin.collections.IntIterator origin=null
           $this: CALL 'public final fun rangeTo (other: kotlin.Int): kotlin.ranges.IntRange [operator] declared in kotlin.Int' type=kotlin.ranges.IntRange origin=null
             $this: CONST Int type=kotlin.Int value=1
             other: CONST Int type=kotlin.Int value=10
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
-          $this: GET_VAR 'val tmp_4: kotlin.collections.IntIterator [val] declared in <root>.testRange' type=kotlin.collections.IntIterator origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:i type:kotlin.Int [val]
-            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=null
-              $this: GET_VAR 'val tmp_4: kotlin.collections.IntIterator [val] declared in <root>.testRange' type=kotlin.collections.IntIterator origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
+          $this: GET_VAR 'val tmp_3: kotlin.collections.IntIterator [val] declared in <root>.testRange' type=kotlin.collections.IntIterator origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:i type:kotlin.Int [val]
+            CALL 'public final fun next (): kotlin.Int [operator] declared in kotlin.collections.IntIterator' type=kotlin.Int origin=FOR_LOOP_NEXT
+              $this: GET_VAR 'val tmp_3: kotlin.collections.IntIterator [val] declared in <root>.testRange' type=kotlin.collections.IntIterator origin=null
diff --git a/compiler/testData/ir/irText/expressions/forWithBreakContinue.fir.txt b/compiler/testData/ir/irText/expressions/forWithBreakContinue.fir.txt
index 581900ed60e..4ae10d31bdb 100644
--- a/compiler/testData/ir/irText/expressions/forWithBreakContinue.fir.txt
+++ b/compiler/testData/ir/irText/expressions/forWithBreakContinue.fir.txt
@@ -2,39 +2,39 @@ FILE fqName:<root> fileName:/forWithBreakContinue.kt
   FUN name:testForBreak1 visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.collections.Iterator<kotlin.String> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_0 type:kotlin.collections.Iterator<kotlin.String> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testForBreak1' type=kotlin.collections.List<kotlin.String> origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_0: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForBreak1' type=kotlin.collections.Iterator<kotlin.String> origin=null
-        body: BLOCK type=kotlin.Nothing origin=null
-          VAR name:s type:kotlin.String [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+        body: BLOCK type=kotlin.Nothing origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:s type:kotlin.String [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_0: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForBreak1' type=kotlin.collections.Iterator<kotlin.String> origin=null
           BREAK label=null loop.label=null
   FUN name:testForBreak2 visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.collections.Iterator<kotlin.String> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_1 type:kotlin.collections.Iterator<kotlin.String> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testForBreak2' type=kotlin.collections.List<kotlin.String> origin=null
       WHILE label=OUTER origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_1: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForBreak2' type=kotlin.collections.Iterator<kotlin.String> origin=null
-        body: BLOCK type=kotlin.Nothing origin=null
-          VAR name:s1 type:kotlin.String [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+        body: BLOCK type=kotlin.Nothing origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:s1 type:kotlin.String [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_1: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForBreak2' type=kotlin.collections.Iterator<kotlin.String> origin=null
-          VAR IR_TEMPORARY_VARIABLE name:tmp_2 type:kotlin.collections.Iterator<kotlin.String> [val]
-            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+          VAR FOR_LOOP_ITERATOR name:tmp_2 type:kotlin.collections.Iterator<kotlin.String> [val]
+            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
               $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testForBreak2' type=kotlin.collections.List<kotlin.String> origin=null
           WHILE label=INNER origin=FOR_LOOP_INNER_WHILE
-            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
               $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForBreak2' type=kotlin.collections.Iterator<kotlin.String> origin=null
-            body: BLOCK type=kotlin.Nothing origin=null
-              VAR name:s2 type:kotlin.String [val]
-                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+            body: BLOCK type=kotlin.Nothing origin=FOR_LOOP_INNER_WHILE
+              VAR FOR_LOOP_VARIABLE name:s2 type:kotlin.String [val]
+                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
                   $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForBreak2' type=kotlin.collections.Iterator<kotlin.String> origin=null
               BREAK label=OUTER loop.label=OUTER
               BREAK label=INNER loop.label=INNER
@@ -43,39 +43,39 @@ FILE fqName:<root> fileName:/forWithBreakContinue.kt
   FUN name:testForContinue1 visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_3 type:kotlin.collections.Iterator<kotlin.String> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_3 type:kotlin.collections.Iterator<kotlin.String> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testForContinue1' type=kotlin.collections.List<kotlin.String> origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_3: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForContinue1' type=kotlin.collections.Iterator<kotlin.String> origin=null
-        body: BLOCK type=kotlin.Nothing origin=null
-          VAR name:s type:kotlin.String [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+        body: BLOCK type=kotlin.Nothing origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:s type:kotlin.String [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_3: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForContinue1' type=kotlin.collections.Iterator<kotlin.String> origin=null
           CONTINUE label=null loop.label=null
   FUN name:testForContinue2 visibility:public modality:FINAL <> (ss:kotlin.collections.List<kotlin.String>) returnType:kotlin.Unit
     VALUE_PARAMETER name:ss index:0 type:kotlin.collections.List<kotlin.String>
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_4 type:kotlin.collections.Iterator<kotlin.String> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_4 type:kotlin.collections.Iterator<kotlin.String> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
           $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testForContinue2' type=kotlin.collections.List<kotlin.String> origin=null
       WHILE label=OUTER origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_4: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForContinue2' type=kotlin.collections.Iterator<kotlin.String> origin=null
-        body: BLOCK type=kotlin.Nothing origin=null
-          VAR name:s1 type:kotlin.String [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+        body: BLOCK type=kotlin.Nothing origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:s1 type:kotlin.String [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_4: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForContinue2' type=kotlin.collections.Iterator<kotlin.String> origin=null
-          VAR IR_TEMPORARY_VARIABLE name:tmp_5 type:kotlin.collections.Iterator<kotlin.String> [val]
-            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=null
+          VAR FOR_LOOP_ITERATOR name:tmp_5 type:kotlin.collections.Iterator<kotlin.String> [val]
+            CALL 'public abstract fun iterator (): kotlin.collections.Iterator<kotlin.String> [operator] declared in kotlin.collections.List' type=kotlin.collections.Iterator<kotlin.String> origin=FOR_LOOP_ITERATOR
               $this: GET_VAR 'ss: kotlin.collections.List<kotlin.String> declared in <root>.testForContinue2' type=kotlin.collections.List<kotlin.String> origin=null
           WHILE label=INNER origin=FOR_LOOP_INNER_WHILE
-            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+            condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
               $this: GET_VAR 'val tmp_5: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForContinue2' type=kotlin.collections.Iterator<kotlin.String> origin=null
-            body: BLOCK type=kotlin.Nothing origin=null
-              VAR name:s2 type:kotlin.String [val]
-                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=null
+            body: BLOCK type=kotlin.Nothing origin=FOR_LOOP_INNER_WHILE
+              VAR FOR_LOOP_VARIABLE name:s2 type:kotlin.String [val]
+                CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=kotlin.String origin=FOR_LOOP_NEXT
                   $this: GET_VAR 'val tmp_5: kotlin.collections.Iterator<kotlin.String> [val] declared in <root>.testForContinue2' type=kotlin.collections.Iterator<kotlin.String> origin=null
               CONTINUE label=OUTER loop.label=OUTER
               CONTINUE label=INNER loop.label=INNER
diff --git a/compiler/testData/ir/irText/expressions/forWithImplicitReceivers.fir.txt b/compiler/testData/ir/irText/expressions/forWithImplicitReceivers.fir.txt
index 9eb3400bc04..972850c5c84 100644
--- a/compiler/testData/ir/irText/expressions/forWithImplicitReceivers.fir.txt
+++ b/compiler/testData/ir/irText/expressions/forWithImplicitReceivers.fir.txt
@@ -105,13 +105,13 @@ FILE fqName:<root> fileName:/forWithImplicitReceivers.kt
   FUN name:test visibility:public modality:FINAL <> ($receiver:<root>.IReceiver) returnType:kotlin.Unit
     $receiver: VALUE_PARAMETER name:<this> type:<root>.IReceiver
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:<root>.IntCell [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_1 type:<root>.IntCell [val]
         CALL 'public open fun iterator (): <root>.IntCell [operator] declared in <root>.IReceiver' type=<root>.IntCell origin=null
           $this: GET_VAR '<this>: <root>.IReceiver declared in <root>.test' type=<root>.IReceiver origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
         condition: CALL 'public open fun hasNext (): kotlin.Boolean [operator] declared in <root>.IReceiver' type=kotlin.Boolean origin=null
           $this: GET_VAR '<this>: <root>.IReceiver declared in <root>.test' type=<root>.IReceiver origin=null
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
           VAR name:i type:kotlin.Int [val]
             CALL 'public open fun next (): kotlin.Int [operator] declared in <root>.IReceiver' type=kotlin.Int origin=null
               $this: GET_VAR '<this>: <root>.IReceiver declared in <root>.test' type=<root>.IReceiver origin=null
diff --git a/compiler/testData/ir/irText/expressions/whileDoWhile.fir.txt b/compiler/testData/ir/irText/expressions/whileDoWhile.fir.txt
index 3079a7b4312..27c9df623cd 100644
--- a/compiler/testData/ir/irText/expressions/whileDoWhile.fir.txt
+++ b/compiler/testData/ir/irText/expressions/whileDoWhile.fir.txt
@@ -7,7 +7,7 @@ FILE fqName:<root> fileName:/whileDoWhile.kt
         condition: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
           arg0: GET_VAR 'var x: kotlin.Int [var] declared in <root>.test' type=kotlin.Int origin=null
           arg1: CONST Int type=kotlin.Int value=0
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
       WHILE label=null origin=WHILE_LOOP
         condition: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
           arg0: GET_VAR 'var x: kotlin.Int [var] declared in <root>.test' type=kotlin.Int origin=null
@@ -23,7 +23,7 @@ FILE fqName:<root> fileName:/whileDoWhile.kt
         condition: CALL 'public final fun less (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=LT
           arg0: GET_VAR 'var x: kotlin.Int [var] declared in <root>.test' type=kotlin.Int origin=null
           arg1: CONST Int type=kotlin.Int value=10
-        body: BLOCK type=kotlin.Int origin=null
+        body: BLOCK type=kotlin.Int origin=WHILE_LOOP
           VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.Int [val]
             GET_VAR 'var x: kotlin.Int [var] declared in <root>.test' type=kotlin.Int origin=null
           SET_VAR 'var x: kotlin.Int [var] declared in <root>.test' type=kotlin.Unit origin=null
@@ -69,7 +69,7 @@ FILE fqName:<root> fileName:/whileDoWhile.kt
             WHILE label=null origin=WHILE_LOOP
               condition: TYPE_OP type=kotlin.Boolean origin=IMPLICIT_CAST typeOperand=kotlin.Boolean
                 GET_VAR 'val a: kotlin.Any? [val] declared in <root>.testSmartcastInCondition' type=kotlin.Any? origin=null
-              body: BLOCK type=kotlin.Unit origin=null
+              body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
             DO_WHILE label=null origin=DO_WHILE_LOOP
               body: BLOCK type=kotlin.Unit origin=null
               condition: TYPE_OP type=kotlin.Boolean origin=IMPLICIT_CAST typeOperand=kotlin.Boolean
diff --git a/compiler/testData/ir/irText/regressions/coercionInLoop.fir.txt b/compiler/testData/ir/irText/regressions/coercionInLoop.fir.txt
index 7d02f6bb97b..07f4212b537 100644
--- a/compiler/testData/ir/irText/regressions/coercionInLoop.fir.txt
+++ b/compiler/testData/ir/irText/regressions/coercionInLoop.fir.txt
@@ -12,7 +12,7 @@ FILE fqName:<root> fileName:/coercionInLoop.kt
       WHILE label=null origin=WHILE_LOOP
         condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
           $this: GET_VAR 'val x: kotlin.collections.DoubleIterator [val] declared in <root>.box' type=kotlin.collections.DoubleIterator origin=null
-        body: BLOCK type=kotlin.Int origin=null
+        body: BLOCK type=kotlin.Int origin=WHILE_LOOP
           WHEN type=kotlin.Unit origin=IF
             BRANCH
               if: CALL 'public final fun not (): kotlin.Boolean [operator] declared in kotlin.Boolean' type=kotlin.Boolean origin=EXCLEQ
diff --git a/compiler/testData/ir/irText/types/nullChecks/enhancedNullabilityInForLoop.fir.txt b/compiler/testData/ir/irText/types/nullChecks/enhancedNullabilityInForLoop.fir.txt
index 199a540b8a6..a04beaea2a4 100644
--- a/compiler/testData/ir/irText/types/nullChecks/enhancedNullabilityInForLoop.fir.txt
+++ b/compiler/testData/ir/irText/types/nullChecks/enhancedNullabilityInForLoop.fir.txt
@@ -4,34 +4,34 @@ FILE fqName:<root> fileName:/enhancedNullabilityInForLoop.kt
     BLOCK_BODY
   FUN name:testForInListUnused visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_0 type:kotlin.collections.MutableIterator<<root>.P> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.MutableIterator<<root>.P> [operator] declared in kotlin.collections.MutableCollection' type=kotlin.collections.MutableIterator<<root>.P> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_0 type:kotlin.collections.MutableIterator<<root>.P> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.MutableIterator<<root>.P> [operator] declared in kotlin.collections.MutableCollection' type=kotlin.collections.MutableIterator<<root>.P> origin=FOR_LOOP_ITERATOR
           $this: CALL 'public open fun listOfNotNull (): kotlin.collections.List<<root>.P>? [operator] declared in <root>.J' type=kotlin.collections.List<<root>.P>? origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_0: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListUnused' type=kotlin.collections.MutableIterator<<root>.P> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:x type:<root>.P [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:x type:<root>.P [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_0: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListUnused' type=kotlin.collections.MutableIterator<<root>.P> origin=null
   FUN name:testForInListDestructured visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_1 type:kotlin.collections.MutableIterator<<root>.P> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.MutableIterator<<root>.P> [operator] declared in kotlin.collections.MutableCollection' type=kotlin.collections.MutableIterator<<root>.P> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_1 type:kotlin.collections.MutableIterator<<root>.P> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.MutableIterator<<root>.P> [operator] declared in kotlin.collections.MutableCollection' type=kotlin.collections.MutableIterator<<root>.P> origin=FOR_LOOP_ITERATOR
           $this: CALL 'public open fun listOfNotNull (): kotlin.collections.List<<root>.P>? [operator] declared in <root>.J' type=kotlin.collections.List<<root>.P>? origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
           $this: GET_VAR 'val tmp_1: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListDestructured' type=kotlin.collections.MutableIterator<<root>.P> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR IR_TEMPORARY_VARIABLE name:tmp_2 type:<root>.P [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:<destruct> type:<root>.P [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=FOR_LOOP_NEXT
               $this: GET_VAR 'val tmp_1: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListDestructured' type=kotlin.collections.MutableIterator<<root>.P> origin=null
           VAR name:x type:kotlin.Int [val]
             CALL 'public final fun component1 (): kotlin.Int declared in <root>.P' type=kotlin.Int origin=null
-              $this: GET_VAR 'val tmp_2: <root>.P [val] declared in <root>.testForInListDestructured' type=<root>.P origin=null
+              $this: GET_VAR 'val <destruct>: <root>.P [val] declared in <root>.testForInListDestructured' type=<root>.P origin=null
           VAR name:y type:kotlin.Int [val]
             CALL 'public final fun component2 (): kotlin.Int declared in <root>.P' type=kotlin.Int origin=null
-              $this: GET_VAR 'val tmp_2: <root>.P [val] declared in <root>.testForInListDestructured' type=<root>.P origin=null
+              $this: GET_VAR 'val <destruct>: <root>.P [val] declared in <root>.testForInListDestructured' type=<root>.P origin=null
   FUN name:testDesugaredForInList visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
       VAR name:iterator type:kotlin.collections.MutableIterator<<root>.P> [val]
@@ -40,36 +40,36 @@ FILE fqName:<root> fileName:/enhancedNullabilityInForLoop.kt
       WHILE label=null origin=WHILE_LOOP
         condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
           $this: GET_VAR 'val iterator: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testDesugaredForInList' type=kotlin.collections.MutableIterator<<root>.P> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
+        body: BLOCK type=kotlin.Unit origin=WHILE_LOOP
           VAR name:x type:<root>.P [val]
             CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=null
               $this: GET_VAR 'val iterator: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testDesugaredForInList' type=kotlin.collections.MutableIterator<<root>.P> origin=null
   FUN name:testForInArrayUnused visibility:public modality:FINAL <> (j:<root>.J) returnType:kotlin.Unit
     VALUE_PARAMETER name:j index:0 type:<root>.J
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_3 type:kotlin.collections.Iterator<<root>.P?> [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_2 type:kotlin.collections.Iterator<<root>.P?> [val]
         CALL 'public final fun iterator (): kotlin.collections.Iterator<<root>.P?> [operator] declared in kotlin.Array' type=kotlin.collections.Iterator<<root>.P?> origin=null
           $this: CALL 'public open fun arrayOfNotNull (): kotlin.Array<out <root>.P?>? [operator] declared in <root>.J' type=kotlin.Array<out <root>.P?>? origin=null
             $this: GET_VAR 'j: <root>.J declared in <root>.testForInArrayUnused' type=<root>.J origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
-          $this: GET_VAR 'val tmp_3: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUnused' type=kotlin.collections.Iterator<<root>.P?> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:x type:<root>.P? [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=<root>.P? origin=null
-              $this: GET_VAR 'val tmp_3: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUnused' type=kotlin.collections.Iterator<<root>.P?> origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
+          $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUnused' type=kotlin.collections.Iterator<<root>.P?> origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:x type:<root>.P? [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=<root>.P? origin=FOR_LOOP_NEXT
+              $this: GET_VAR 'val tmp_2: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUnused' type=kotlin.collections.Iterator<<root>.P?> origin=null
   FUN name:testForInListUse visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_4 type:kotlin.collections.MutableIterator<<root>.P> [val]
-        CALL 'public abstract fun iterator (): kotlin.collections.MutableIterator<<root>.P> [operator] declared in kotlin.collections.MutableCollection' type=kotlin.collections.MutableIterator<<root>.P> origin=null
+      VAR FOR_LOOP_ITERATOR name:tmp_3 type:kotlin.collections.MutableIterator<<root>.P> [val]
+        CALL 'public abstract fun iterator (): kotlin.collections.MutableIterator<<root>.P> [operator] declared in kotlin.collections.MutableCollection' type=kotlin.collections.MutableIterator<<root>.P> origin=FOR_LOOP_ITERATOR
           $this: CALL 'public open fun listOfNotNull (): kotlin.collections.List<<root>.P>? [operator] declared in <root>.J' type=kotlin.collections.List<<root>.P>? origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
-          $this: GET_VAR 'val tmp_4: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListUse' type=kotlin.collections.MutableIterator<<root>.P> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:x type:<root>.P [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=null
-              $this: GET_VAR 'val tmp_4: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListUse' type=kotlin.collections.MutableIterator<<root>.P> origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
+          $this: GET_VAR 'val tmp_3: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListUse' type=kotlin.collections.MutableIterator<<root>.P> origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:x type:<root>.P [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.MutableIterator [operator] declared in kotlin.collections.Iterator' type=<root>.P origin=FOR_LOOP_NEXT
+              $this: GET_VAR 'val tmp_3: kotlin.collections.MutableIterator<<root>.P> [val] declared in <root>.testForInListUse' type=kotlin.collections.MutableIterator<<root>.P> origin=null
           CALL 'public final fun use (s: <root>.P): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
             s: GET_VAR 'val x: <root>.P [val] declared in <root>.testForInListUse' type=<root>.P origin=null
           CALL 'public open fun use (s: <root>.P): kotlin.Unit [operator] declared in <root>.J' type=kotlin.Unit origin=null
@@ -77,17 +77,17 @@ FILE fqName:<root> fileName:/enhancedNullabilityInForLoop.kt
   FUN name:testForInArrayUse visibility:public modality:FINAL <> (j:<root>.J) returnType:kotlin.Unit
     VALUE_PARAMETER name:j index:0 type:<root>.J
     BLOCK_BODY
-      VAR IR_TEMPORARY_VARIABLE name:tmp_5 type:kotlin.collections.Iterator<<root>.P?> [val]
+      VAR FOR_LOOP_ITERATOR name:tmp_4 type:kotlin.collections.Iterator<<root>.P?> [val]
         CALL 'public final fun iterator (): kotlin.collections.Iterator<<root>.P?> [operator] declared in kotlin.Array' type=kotlin.collections.Iterator<<root>.P?> origin=null
           $this: CALL 'public open fun arrayOfNotNull (): kotlin.Array<out <root>.P?>? [operator] declared in <root>.J' type=kotlin.Array<out <root>.P?>? origin=null
             $this: GET_VAR 'j: <root>.J declared in <root>.testForInArrayUse' type=<root>.J origin=null
       WHILE label=null origin=FOR_LOOP_INNER_WHILE
-        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=null
-          $this: GET_VAR 'val tmp_5: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUse' type=kotlin.collections.Iterator<<root>.P?> origin=null
-        body: BLOCK type=kotlin.Unit origin=null
-          VAR name:x type:<root>.P? [val]
-            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=<root>.P? origin=null
-              $this: GET_VAR 'val tmp_5: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUse' type=kotlin.collections.Iterator<<root>.P?> origin=null
+        condition: CALL 'public abstract fun hasNext (): kotlin.Boolean [operator] declared in kotlin.collections.Iterator' type=kotlin.Boolean origin=FOR_LOOP_HAS_NEXT
+          $this: GET_VAR 'val tmp_4: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUse' type=kotlin.collections.Iterator<<root>.P?> origin=null
+        body: BLOCK type=kotlin.Unit origin=FOR_LOOP_INNER_WHILE
+          VAR FOR_LOOP_VARIABLE name:x type:<root>.P? [val]
+            CALL 'public abstract fun next (): T of kotlin.collections.Iterator [operator] declared in kotlin.collections.Iterator' type=<root>.P? origin=FOR_LOOP_NEXT
+              $this: GET_VAR 'val tmp_4: kotlin.collections.Iterator<<root>.P?> [val] declared in <root>.testForInArrayUse' type=kotlin.collections.Iterator<<root>.P?> origin=null
           CALL 'public final fun use (s: <root>.P): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
             s: GET_VAR 'val x: <root>.P? [val] declared in <root>.testForInArrayUse' type=<root>.P? origin=null
           CALL 'public open fun use (s: <root>.P): kotlin.Unit [operator] declared in <root>.J' type=kotlin.Unit origin=null