diff --git a/compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypes.kt b/compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypes.kt
index f59e38537a8..bdb79b6110f 100644
--- a/compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypes.kt
+++ b/compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/types/irTypes.kt
@@ -22,7 +22,13 @@ fun IrType.withHasQuestionMark(hasQuestionMark: Boolean): IrType =
             if (this.hasQuestionMark == hasQuestionMark)
                 this
             else
-                IrSimpleTypeImpl(originalKotlinType, classifier, hasQuestionMark, arguments, annotations)
+                IrSimpleTypeImpl(
+                    makeKotlinType(classifier, arguments, hasQuestionMark),
+                    classifier,
+                    hasQuestionMark,
+                    arguments,
+                    annotations
+                )
         else -> this
     }
 
@@ -35,7 +41,7 @@ val IrType.classifierOrNull: IrClassifierSymbol?
 fun IrType.makeNotNull() =
     if (this is IrSimpleType && this.hasQuestionMark)
         IrSimpleTypeImpl(
-            originalKotlinType,
+            makeKotlinType(classifier, arguments, false),
             classifier,
             false,
             arguments,
@@ -48,7 +54,7 @@ fun IrType.makeNotNull() =
 fun IrType.makeNullable() =
     if (this is IrSimpleType && !this.hasQuestionMark)
         IrSimpleTypeImpl(
-            originalKotlinType,
+            makeKotlinType(classifier, arguments, true),
             classifier,
             true,
             arguments,
@@ -64,22 +70,26 @@ fun IrType.toKotlinType(): KotlinType {
     }
 
     return when (this) {
-        is IrSimpleType -> {
-            val classifier = classifier.descriptor
-            val arguments = arguments.mapIndexed { index, it ->
-                when (it) {
-                    is IrTypeProjection -> TypeProjectionImpl(it.variance, it.type.toKotlinType())
-                    is IrStarProjection -> StarProjectionImpl((classifier as ClassDescriptor).declaredTypeParameters[index])
-                    else -> error(it)
-                }
-            }
-
-            classifier.defaultType.replace(newArguments = arguments).makeNullableAsSpecified(hasQuestionMark)
-        }
+        is IrSimpleType -> makeKotlinType(classifier, arguments, hasQuestionMark)
         else -> TODO(toString())
     }
 }
 
+private fun makeKotlinType(
+    classifier: IrClassifierSymbol,
+    arguments: List<IrTypeArgument>,
+    hasQuestionMark: Boolean
+): SimpleType {
+    val kotlinTypeArguments = arguments.mapIndexed { index, it ->
+        when (it) {
+            is IrTypeProjection -> TypeProjectionImpl(it.variance, it.type.toKotlinType())
+            is IrStarProjection -> StarProjectionImpl((classifier.descriptor as ClassDescriptor).declaredTypeParameters[index])
+            else -> error(it)
+        }
+    }
+    return classifier.descriptor.defaultType.replace(newArguments = kotlinTypeArguments).makeNullableAsSpecified(hasQuestionMark)
+}
+
 fun ClassifierDescriptor.toIrType(hasQuestionMark: Boolean = false): IrType {
     val symbol = getSymbol()
     return IrSimpleTypeImpl(defaultType, symbol, hasQuestionMark, listOf(), listOf())
diff --git a/compiler/testData/ir/irText/classes/dataClassWithArrayMembers.txt b/compiler/testData/ir/irText/classes/dataClassWithArrayMembers.txt
index 23e82c29000..462af0ba0a7 100644
--- a/compiler/testData/ir/irText/classes/dataClassWithArrayMembers.txt
+++ b/compiler/testData/ir/irText/classes/dataClassWithArrayMembers.txt
@@ -624,7 +624,7 @@ FILE fqName:<root> fileName:/dataClassWithArrayMembers.kt
               BRANCH
                 if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                   arg0: GET_VAR 'tmp1: Array<Any>?' type=kotlin.Array<kotlin.Any>? origin=null
-                  arg1: CONST Null type=kotlin.Nothing value=null
+                  arg1: CONST Null type=kotlin.Nothing? value=null
                 then: CONST Int type=kotlin.Int value=0
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/classes/dataClasses.txt b/compiler/testData/ir/irText/classes/dataClasses.txt
index 52f439d9893..f54094ae5c3 100644
--- a/compiler/testData/ir/irText/classes/dataClasses.txt
+++ b/compiler/testData/ir/irText/classes/dataClasses.txt
@@ -246,7 +246,7 @@ FILE fqName:<root> fileName:/dataClasses.kt
               BRANCH
                 if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                   arg0: GET_VAR 'tmp1: Any?' type=kotlin.Any? origin=null
-                  arg1: CONST Null type=kotlin.Nothing value=null
+                  arg1: CONST Null type=kotlin.Nothing? value=null
                 then: CONST Int type=kotlin.Int value=0
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
@@ -441,7 +441,7 @@ FILE fqName:<root> fileName:/dataClasses.kt
                 BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp1: Double?' type=kotlin.Double? origin=null
-                    arg1: CONST Null type=kotlin.Nothing value=null
+                    arg1: CONST Null type=kotlin.Nothing? value=null
                   then: CONST Int type=kotlin.Int value=0
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
@@ -468,7 +468,7 @@ FILE fqName:<root> fileName:/dataClasses.kt
                 BRANCH
                   if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                     arg0: GET_VAR 'tmp2: Float?' type=kotlin.Float? origin=null
-                    arg1: CONST Null type=kotlin.Nothing value=null
+                    arg1: CONST Null type=kotlin.Nothing? value=null
                   then: CONST Int type=kotlin.Int value=0
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/classes/dataClassesGeneric.txt b/compiler/testData/ir/irText/classes/dataClassesGeneric.txt
index 9555761a877..5c34d4ce39f 100644
--- a/compiler/testData/ir/irText/classes/dataClassesGeneric.txt
+++ b/compiler/testData/ir/irText/classes/dataClassesGeneric.txt
@@ -63,7 +63,7 @@ FILE fqName:<root> fileName:/dataClassesGeneric.kt
               BRANCH
                 if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                   arg0: GET_VAR 'tmp1: T' type=T origin=null
-                  arg1: CONST Null type=kotlin.Nothing value=null
+                  arg1: CONST Null type=kotlin.Nothing? value=null
                 then: CONST Int type=kotlin.Int value=0
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/declarations/parameters/dataClassMembers.txt b/compiler/testData/ir/irText/declarations/parameters/dataClassMembers.txt
index 69f14f2009a..4c1f7696737 100644
--- a/compiler/testData/ir/irText/declarations/parameters/dataClassMembers.txt
+++ b/compiler/testData/ir/irText/declarations/parameters/dataClassMembers.txt
@@ -92,7 +92,7 @@ FILE fqName:<root> fileName:/dataClassMembers.kt
               BRANCH
                 if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                   arg0: GET_VAR 'tmp1: T' type=T origin=null
-                  arg1: CONST Null type=kotlin.Nothing value=null
+                  arg1: CONST Null type=kotlin.Nothing? value=null
                 then: CONST Int type=kotlin.Int value=0
               BRANCH
                 if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/expressions/bangbang.txt b/compiler/testData/ir/irText/expressions/bangbang.txt
index 688fe874fbb..a4eb1c1f468 100644
--- a/compiler/testData/ir/irText/expressions/bangbang.txt
+++ b/compiler/testData/ir/irText/expressions/bangbang.txt
@@ -3,14 +3,14 @@ FILE fqName:<root> fileName:/bangbang.kt
     VALUE_PARAMETER name:a index:0 type:kotlin.Any? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test1(Any?): Any'
-        BLOCK type=kotlin.Any? origin=EXCLEXCL
+        BLOCK type=kotlin.Any origin=EXCLEXCL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_notnull type:kotlin.Any? flags:val
             GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
-          WHEN 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
+                arg1: CONST Null type=kotlin.Nothing? value=null
               then: CALL 'THROW_NPE(): Nothing' type=kotlin.Nothing origin=EXCLEXCL
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
@@ -20,16 +20,16 @@ FILE fqName:<root> fileName:/bangbang.kt
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test2(Any?): Int'
         BLOCK type=kotlin.Int origin=EXCLEXCL
-          VAR IR_TEMPORARY_VARIABLE name:tmp1_notnull type:kotlin.Int flags:val
-            BLOCK type=kotlin.Int origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp1_notnull type:kotlin.Int? flags:val
+            BLOCK type=kotlin.Int? origin=SAFE_CALL
               VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Any? flags:val
                 GET_VAR 'value-parameter a: Any?' type=kotlin.Any? origin=null
-              WHEN type=kotlin.Int origin=null
+              WHEN type=kotlin.Int? origin=null
                 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
+                    arg1: CONST Null type=kotlin.Nothing? value=null
+                  then: CONST Null type=kotlin.Nothing? value=null
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
                   then: CALL 'hashCode(): Int' type=kotlin.Int origin=null
@@ -37,10 +37,10 @@ FILE fqName:<root> fileName:/bangbang.kt
           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
+                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
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
-              then: GET_VAR 'tmp1_notnull: Int' type=kotlin.Int origin=null
+              then: GET_VAR 'tmp1_notnull: Int?' type=kotlin.Int? origin=null
 
diff --git a/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.txt b/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.txt
index d9e482a3a9d..54c2d591cb7 100644
--- a/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.txt
+++ b/compiler/testData/ir/irText/expressions/breakContinueInLoopHeader.txt
@@ -13,7 +13,7 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                 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
+                    arg1: CONST Null type=kotlin.Nothing? value=null
                   then: BREAK label=null loop.label=L
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
@@ -32,7 +32,7 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                 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
+                    arg1: CONST Null type=kotlin.Nothing? value=null
                   then: CONTINUE label=null loop.label=L
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
@@ -53,7 +53,7 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                     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
+                        arg1: CONST Null type=kotlin.Nothing? value=null
                       then: CONTINUE label=null loop.label=L
                     BRANCH
                       if: CONST Boolean type=kotlin.Boolean value=true
@@ -81,7 +81,7 @@ FILE fqName:<root> fileName:/breakContinueInLoopHeader.kt
                     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
+                        arg1: CONST Null type=kotlin.Nothing? value=null
                       then: BREAK label=null loop.label=L
                     BRANCH
                       if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/expressions/chainOfSafeCalls.txt b/compiler/testData/ir/irText/expressions/chainOfSafeCalls.txt
index 289ad4a83ea..ad894b994db 100644
--- a/compiler/testData/ir/irText/expressions/chainOfSafeCalls.txt
+++ b/compiler/testData/ir/irText/expressions/chainOfSafeCalls.txt
@@ -32,21 +32,21 @@ FILE fqName:<root> fileName:/chainOfSafeCalls.kt
     VALUE_PARAMETER name:nc index:0 type:C? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test(C?): C?'
-        BLOCK type=C origin=SAFE_CALL
-          VAR IR_TEMPORARY_VARIABLE name:tmp3_safe_receiver type:C flags:val
-            BLOCK type=C origin=SAFE_CALL
+        BLOCK type=C? origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp3_safe_receiver type:C? flags:val
+            BLOCK type=C? origin=SAFE_CALL
               VAR IR_TEMPORARY_VARIABLE name:tmp2_safe_receiver type:C? flags:val
                 BLOCK type=C? origin=SAFE_CALL
-                  VAR IR_TEMPORARY_VARIABLE name:tmp1_safe_receiver type:C flags:val
-                    BLOCK type=C origin=SAFE_CALL
+                  VAR IR_TEMPORARY_VARIABLE name:tmp1_safe_receiver type:C? flags:val
+                    BLOCK type=C? origin=SAFE_CALL
                       VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:C? flags:val
                         GET_VAR 'value-parameter nc: C?' type=C? origin=null
-                      WHEN type=C origin=null
+                      WHEN type=C? origin=null
                         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
+                            arg1: CONST Null type=kotlin.Nothing? value=null
+                          then: CONST Null type=kotlin.Nothing? value=null
                         BRANCH
                           if: CONST Boolean type=kotlin.Boolean value=true
                           then: CALL 'foo(): C' type=C origin=null
@@ -54,31 +54,31 @@ FILE fqName:<root> fileName:/chainOfSafeCalls.kt
                   WHEN type=C? origin=null
                     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
+                        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
                     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=null
+                        $this: GET_VAR 'tmp1_safe_receiver: C?' type=C? origin=null
+              WHEN type=C? origin=null
                 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
+                    arg1: CONST Null type=kotlin.Nothing? value=null
+                  then: CONST Null type=kotlin.Nothing? value=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=null
+          WHEN type=C? origin=null
             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
+                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
             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
+                $this: GET_VAR 'tmp3_safe_receiver: C?' type=C? origin=null
 
diff --git a/compiler/testData/ir/irText/expressions/coercionToUnit.txt b/compiler/testData/ir/irText/expressions/coercionToUnit.txt
index 1c67c747767..45a86993a78 100644
--- a/compiler/testData/ir/irText/expressions/coercionToUnit.txt
+++ b/compiler/testData/ir/irText/expressions/coercionToUnit.txt
@@ -25,32 +25,36 @@ FILE fqName:<root> fileName:/coercionToUnit.kt
           element: CONST String type=kotlin.String value=
   FUN name:test3 visibility:public modality:FINAL <> () returnType:kotlin.Unit flags:
     BLOCK_BODY
-      BLOCK type=kotlin.Unit origin=SAFE_CALL
-        VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:java.io.PrintStream? flags:val
-          GET_FIELD 'out: PrintStream!' type=java.io.PrintStream? origin=GET_PROPERTY
-        WHEN type=kotlin.Unit origin=null
-          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
-          BRANCH
-            if: CONST Boolean type=kotlin.Boolean value=true
-            then: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
-              $this: GET_VAR 'tmp0_safe_receiver: PrintStream?' type=java.io.PrintStream? origin=null
-              x: CONST String type=kotlin.String value=Hello,
-      BLOCK type=kotlin.Unit origin=SAFE_CALL
-        VAR IR_TEMPORARY_VARIABLE name:tmp1_safe_receiver type:java.io.PrintStream? flags:val
-          GET_FIELD 'out: PrintStream!' type=java.io.PrintStream? origin=GET_PROPERTY
-        WHEN type=kotlin.Unit origin=null
-          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
-          BRANCH
-            if: CONST Boolean type=kotlin.Boolean value=true
-            then: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
-              $this: GET_VAR 'tmp1_safe_receiver: PrintStream?' type=java.io.PrintStream? origin=null
-              x: CONST String type=kotlin.String value=world!
+      TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+        typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
+        BLOCK type=kotlin.Unit? origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:java.io.PrintStream? flags:val
+            GET_FIELD 'out: PrintStream!' type=java.io.PrintStream? origin=GET_PROPERTY
+          WHEN type=kotlin.Unit? origin=null
+            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
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
+                $this: GET_VAR 'tmp0_safe_receiver: PrintStream?' type=java.io.PrintStream? origin=null
+                x: CONST String type=kotlin.String value=Hello,
+      TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+        typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
+        BLOCK type=kotlin.Unit? origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp1_safe_receiver type:java.io.PrintStream? flags:val
+            GET_FIELD 'out: PrintStream!' type=java.io.PrintStream? origin=GET_PROPERTY
+          WHEN type=kotlin.Unit? origin=null
+            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
+            BRANCH
+              if: CONST Boolean type=kotlin.Boolean value=true
+              then: CALL 'println(String!): Unit' type=kotlin.Unit origin=null
+                $this: GET_VAR 'tmp1_safe_receiver: PrintStream?' type=java.io.PrintStream? origin=null
+                x: CONST String type=kotlin.String value=world!
 
diff --git a/compiler/testData/ir/irText/expressions/dotQualified.txt b/compiler/testData/ir/irText/expressions/dotQualified.txt
index 80b21e0fe5b..997e3caa883 100644
--- a/compiler/testData/ir/irText/expressions/dotQualified.txt
+++ b/compiler/testData/ir/irText/expressions/dotQualified.txt
@@ -9,15 +9,15 @@ FILE fqName:<root> fileName:/dotQualified.kt
     VALUE_PARAMETER name:s index:0 type:kotlin.String? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='lengthN(String?): Int?'
-        BLOCK type=kotlin.Int origin=SAFE_CALL
+        BLOCK type=kotlin.Int? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.String? flags:val
             GET_VAR 'value-parameter s: String?' type=kotlin.String? origin=null
-          WHEN type=kotlin.Int origin=null
+          WHEN type=kotlin.Int? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL '<get-length>(): Int' type=kotlin.Int origin=GET_PROPERTY
diff --git a/compiler/testData/ir/irText/expressions/elvis.txt b/compiler/testData/ir/irText/expressions/elvis.txt
index 1d4eef968ef..7c37e764e29 100644
--- a/compiler/testData/ir/irText/expressions/elvis.txt
+++ b/compiler/testData/ir/irText/expressions/elvis.txt
@@ -24,7 +24,7 @@ FILE fqName:<root> fileName:/elvis.kt
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
               then: GET_VAR 'value-parameter b: Any' type=kotlin.Any origin=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
@@ -41,7 +41,7 @@ FILE fqName:<root> fileName:/elvis.kt
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
               then: GET_VAR 'value-parameter b: Any' type=kotlin.Any origin=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
@@ -72,7 +72,7 @@ FILE fqName:<root> fileName:/elvis.kt
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
               then: TYPE_OP type=kotlin.String origin=IMPLICIT_CAST typeOperand=kotlin.String
                 typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB CLASS name:String modality:FINAL visibility:public flags: superTypes:[kotlin.Comparable<kotlin.String>; kotlin.CharSequence; java.io.Serializable]
                 GET_VAR 'value-parameter b: Any?' type=kotlin.Any? origin=null
@@ -92,7 +92,7 @@ FILE fqName:<root> fileName:/elvis.kt
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
               then: GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
@@ -108,7 +108,7 @@ FILE fqName:<root> fileName:/elvis.kt
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
               then: GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/expressions/extFunSafeInvoke.txt b/compiler/testData/ir/irText/expressions/extFunSafeInvoke.txt
index 8312929bb3b..be19c701986 100644
--- a/compiler/testData/ir/irText/expressions/extFunSafeInvoke.txt
+++ b/compiler/testData/ir/irText/expressions/extFunSafeInvoke.txt
@@ -4,15 +4,15 @@ FILE fqName:<root> fileName:/extFunSafeInvoke.kt
     VALUE_PARAMETER name:fn index:1 type:kotlin.Any.(kotlin.Int, kotlin.String) -> kotlin.Unit flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test(Any?, Any.(Int, String) -> Unit): Unit?'
-        BLOCK type=kotlin.Unit origin=SAFE_CALL
+        BLOCK type=kotlin.Unit? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Any? flags:val
             GET_VAR 'value-parameter receiver: Any?' type=kotlin.Any? origin=null
-          WHEN type=kotlin.Unit origin=null
+          WHEN type=kotlin.Unit? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL 'invoke(Any, Int, String): Unit' type=kotlin.Unit origin=INVOKE
diff --git a/compiler/testData/ir/irText/expressions/floatingPointComparisons/eqeqRhsConditionPossiblyAffectingLhs.txt b/compiler/testData/ir/irText/expressions/floatingPointComparisons/eqeqRhsConditionPossiblyAffectingLhs.txt
index 73973ef7f3a..722d8e7ba3e 100644
--- a/compiler/testData/ir/irText/expressions/floatingPointComparisons/eqeqRhsConditionPossiblyAffectingLhs.txt
+++ b/compiler/testData/ir/irText/expressions/floatingPointComparisons/eqeqRhsConditionPossiblyAffectingLhs.txt
@@ -10,14 +10,14 @@ FILE fqName:<root> fileName:/eqeqRhsConditionPossiblyAffectingLhs.kt
               if: TYPE_OP type=kotlin.Boolean origin=NOT_INSTANCEOF typeOperand=kotlin.Double
                 typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB CLASS name:Double modality:FINAL visibility:public flags: superTypes:[kotlin.Number; kotlin.Comparable<kotlin.Double>; java.io.Serializable]
                 GET_VAR 'value-parameter x: Any' type=kotlin.Any origin=null
-              then: BLOCK type=kotlin.Nothing? origin=EXCLEXCL
+              then: BLOCK type=kotlin.Nothing origin=EXCLEXCL
                 VAR IR_TEMPORARY_VARIABLE name:tmp0_notnull type:kotlin.Nothing? flags:val
                   CONST Null type=kotlin.Nothing? value=null
-                WHEN type=kotlin.Nothing? origin=null
+                WHEN type=kotlin.Nothing origin=null
                   BRANCH
                     if: CALL 'EQEQ(Any?, Any?): Boolean' type=kotlin.Boolean origin=EQEQ
                       arg0: GET_VAR 'tmp0_notnull: Nothing?' type=kotlin.Nothing? origin=null
-                      arg1: CONST Null type=kotlin.Nothing value=null
+                      arg1: CONST Null type=kotlin.Nothing? value=null
                     then: CALL 'THROW_NPE(): Nothing' type=kotlin.Nothing origin=EXCLEXCL
                   BRANCH
                     if: CONST Boolean type=kotlin.Boolean value=true
diff --git a/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.txt b/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.txt
index 6798aa3713e..3f9d96ea583 100644
--- a/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.txt
+++ b/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableAnyAsIntToDouble.txt
@@ -10,15 +10,15 @@ FILE fqName:<root> fileName:/nullableAnyAsIntToDouble.kt
               typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB CLASS name:Int modality:FINAL visibility:public flags: superTypes:[kotlin.Number; kotlin.Comparable<kotlin.Int>; java.io.Serializable]
               GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
             then: CALL 'less(Double, Double): Boolean' type=kotlin.Boolean origin=LT
-              arg0: BLOCK type=kotlin.Double origin=SAFE_CALL
+              arg0: BLOCK type=kotlin.Double? origin=SAFE_CALL
                 VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Any? flags:val
                   GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
-                WHEN type=kotlin.Double origin=null
+                WHEN type=kotlin.Double? origin=null
                   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
+                      arg1: CONST Null type=kotlin.Nothing? value=null
+                    then: CONST Null type=kotlin.Nothing? value=null
                   BRANCH
                     if: CONST Boolean type=kotlin.Boolean value=true
                     then: CALL 'toDouble(): Double' type=kotlin.Double origin=null
diff --git a/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableFloatingPointEqeq.txt b/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableFloatingPointEqeq.txt
index ea7f6eb310c..518f880941e 100644
--- a/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableFloatingPointEqeq.txt
+++ b/compiler/testData/ir/irText/expressions/floatingPointComparisons/nullableFloatingPointEqeq.txt
@@ -19,15 +19,15 @@ FILE fqName:<root> fileName:/nullableFloatingPointEqeq.kt
               GET_VAR 'value-parameter y: Any?' type=kotlin.Any? origin=null
             then: CALL 'ieee754equals(Double?, Double?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'value-parameter x: Double?' type=kotlin.Double? origin=null
-              arg1: BLOCK type=kotlin.Double origin=SAFE_CALL
+              arg1: BLOCK type=kotlin.Double? origin=SAFE_CALL
                 VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Any? flags:val
                   GET_VAR 'value-parameter y: Any?' type=kotlin.Any? origin=null
-                WHEN type=kotlin.Double origin=null
+                WHEN type=kotlin.Double? origin=null
                   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
+                      arg1: CONST Null type=kotlin.Nothing? value=null
+                    then: CONST Null type=kotlin.Nothing? value=null
                   BRANCH
                     if: CONST Boolean type=kotlin.Boolean value=true
                     then: CALL 'toDouble(): Double' type=kotlin.Double origin=null
@@ -49,15 +49,15 @@ FILE fqName:<root> fileName:/nullableFloatingPointEqeq.kt
               GET_VAR 'value-parameter y: Any?' type=kotlin.Any? origin=null
             then: CALL 'ieee754equals(Double?, Double?): Boolean' type=kotlin.Boolean origin=EQEQ
               arg0: GET_VAR 'value-parameter x: Double?' type=kotlin.Double? origin=null
-              arg1: BLOCK type=kotlin.Double origin=SAFE_CALL
+              arg1: BLOCK type=kotlin.Double? origin=SAFE_CALL
                 VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Any? flags:val
                   GET_VAR 'value-parameter y: Any?' type=kotlin.Any? origin=null
-                WHEN type=kotlin.Double origin=null
+                WHEN type=kotlin.Double? origin=null
                   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
+                      arg1: CONST Null type=kotlin.Nothing? value=null
+                    then: CONST Null type=kotlin.Nothing? value=null
                   BRANCH
                     if: CONST Boolean type=kotlin.Boolean value=true
                     then: CALL 'toDouble(): Double' type=kotlin.Double origin=null
@@ -86,15 +86,15 @@ FILE fqName:<root> fileName:/nullableFloatingPointEqeq.kt
                 if: CONST Boolean type=kotlin.Boolean value=true
                 then: CONST Boolean type=kotlin.Boolean value=false
             then: CALL 'ieee754equals(Double?, Double?): Boolean' type=kotlin.Boolean origin=EQEQ
-              arg0: BLOCK type=kotlin.Double origin=SAFE_CALL
+              arg0: BLOCK type=kotlin.Double? origin=SAFE_CALL
                 VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Any? flags:val
                   GET_VAR 'value-parameter x: Any?' type=kotlin.Any? origin=null
-                WHEN type=kotlin.Double origin=null
+                WHEN type=kotlin.Double? origin=null
                   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
+                      arg1: CONST Null type=kotlin.Nothing? value=null
+                    then: CONST Null type=kotlin.Nothing? value=null
                   BRANCH
                     if: CONST Boolean type=kotlin.Boolean value=true
                     then: CALL 'toDouble(): Double' type=kotlin.Double origin=null
diff --git a/compiler/testData/ir/irText/expressions/safeAssignment.txt b/compiler/testData/ir/irText/expressions/safeAssignment.txt
index bc29c9a8a0c..5a30d74556f 100644
--- a/compiler/testData/ir/irText/expressions/safeAssignment.txt
+++ b/compiler/testData/ir/irText/expressions/safeAssignment.txt
@@ -48,8 +48,10 @@ FILE fqName:<root> fileName:/safeAssignment.kt
           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
+              arg1: CONST Null type=kotlin.Nothing? value=null
+            then: TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+              typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
+              CONST Null type=kotlin.Nothing? value=null
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: CALL '<set-x>(Int): Unit' type=kotlin.Unit origin=EQ
diff --git a/compiler/testData/ir/irText/expressions/safeCallWithIncrementDecrement.txt b/compiler/testData/ir/irText/expressions/safeCallWithIncrementDecrement.txt
index 36217237a48..cedd02d5885 100644
--- a/compiler/testData/ir/irText/expressions/safeCallWithIncrementDecrement.txt
+++ b/compiler/testData/ir/irText/expressions/safeCallWithIncrementDecrement.txt
@@ -34,15 +34,15 @@ FILE fqName:test fileName:/safeCallWithIncrementDecrement.kt
     $receiver: VALUE_PARAMETER name:<this> type:kotlin.Int? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='inc() on Int?: Int?'
-        BLOCK type=kotlin.Int origin=SAFE_CALL
+        BLOCK type=kotlin.Int? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Int? flags:val
             GET_VAR 'this@inc: Int?' type=kotlin.Int? origin=null
-          WHEN type=kotlin.Int origin=null
+          WHEN type=kotlin.Int? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL 'inc(): Int' type=kotlin.Int origin=null
@@ -68,8 +68,10 @@ FILE fqName:test fileName:/safeCallWithIncrementDecrement.kt
           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
+              arg1: CONST Null type=kotlin.Nothing? value=null
+            then: TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+              typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
+              CONST Null type=kotlin.Nothing? value=null
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
@@ -92,16 +94,16 @@ FILE fqName:test fileName:/safeCallWithIncrementDecrement.kt
       TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
         typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
         BLOCK type=kotlin.Int origin=POSTFIX_INCR
-          VAR IR_TEMPORARY_VARIABLE name:tmp1_array type:kotlin.Int flags:val
-            BLOCK type=kotlin.Int origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp1_array type:kotlin.Int? flags:val
+            BLOCK type=kotlin.Int? origin=SAFE_CALL
               VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:test.C? flags:val
                 GET_VAR 'value-parameter nc: C?' type=test.C? origin=null
-              WHEN type=kotlin.Int origin=null
+              WHEN type=kotlin.Int? origin=null
                 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
+                    arg1: CONST Null type=kotlin.Nothing? value=null
+                  then: CONST Null type=kotlin.Nothing? value=null
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
                   then: CALL '<get-p>() on C?: Int' type=kotlin.Int origin=GET_PROPERTY
@@ -110,10 +112,10 @@ FILE fqName:test fileName:/safeCallWithIncrementDecrement.kt
             CONST Int type=kotlin.Int value=0
           VAR IR_TEMPORARY_VARIABLE name:tmp3 type:kotlin.Int flags:val
             CALL 'get(Int) on Int?: Int' type=kotlin.Int origin=POSTFIX_INCR
-              $receiver: GET_VAR 'tmp1_array: Int' type=kotlin.Int origin=null
+              $receiver: GET_VAR 'tmp1_array: Int?' type=kotlin.Int? origin=null
               index: GET_VAR 'tmp2_index0: Int' type=kotlin.Int origin=null
           CALL 'set(Int, Int) on Int?: Unit' type=kotlin.Unit origin=POSTFIX_INCR
-            $receiver: GET_VAR 'tmp1_array: Int' type=kotlin.Int origin=null
+            $receiver: GET_VAR 'tmp1_array: Int?' type=kotlin.Int? origin=null
             index: GET_VAR 'tmp2_index0: Int' type=kotlin.Int origin=null
             value: CALL 'inc(): Int' type=kotlin.Int origin=POSTFIX_INCR
               $this: GET_VAR 'tmp3: Int' type=kotlin.Int origin=null
diff --git a/compiler/testData/ir/irText/expressions/safeCalls.txt b/compiler/testData/ir/irText/expressions/safeCalls.txt
index f1879c3cb68..2c44fb26719 100644
--- a/compiler/testData/ir/irText/expressions/safeCalls.txt
+++ b/compiler/testData/ir/irText/expressions/safeCalls.txt
@@ -64,15 +64,15 @@ FILE fqName:<root> fileName:/safeCalls.kt
     VALUE_PARAMETER name:x index:0 type:kotlin.String? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test1(String?): Int?'
-        BLOCK type=kotlin.Int origin=SAFE_CALL
+        BLOCK type=kotlin.Int? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.String? flags:val
             GET_VAR 'value-parameter x: String?' type=kotlin.String? origin=null
-          WHEN type=kotlin.Int origin=null
+          WHEN type=kotlin.Int? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL '<get-length>(): Int' type=kotlin.Int origin=GET_PROPERTY
@@ -81,15 +81,15 @@ FILE fqName:<root> fileName:/safeCalls.kt
     VALUE_PARAMETER name:x index:0 type:kotlin.String? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test2(String?): Int?'
-        BLOCK type=kotlin.Int origin=SAFE_CALL
+        BLOCK type=kotlin.Int? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.String? flags:val
             GET_VAR 'value-parameter x: String?' type=kotlin.String? origin=null
-          WHEN type=kotlin.Int origin=null
+          WHEN type=kotlin.Int? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL 'hashCode(): Int' type=kotlin.Int origin=null
@@ -99,15 +99,15 @@ FILE fqName:<root> fileName:/safeCalls.kt
     VALUE_PARAMETER name:y index:1 type:kotlin.Any? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test3(String?, Any?): Boolean?'
-        BLOCK type=kotlin.Boolean origin=SAFE_CALL
+        BLOCK type=kotlin.Boolean? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.String? flags:val
             GET_VAR 'value-parameter x: String?' type=kotlin.String? origin=null
-          WHEN 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_safe_receiver: String?' type=kotlin.String? origin=null
-                arg1: CONST Null type=kotlin.Nothing value=null
-              then: CONST Null type=kotlin.Nothing value=null
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL 'equals(Any?): Boolean' type=kotlin.Boolean origin=null
@@ -123,8 +123,10 @@ FILE fqName:<root> fileName:/safeCalls.kt
           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: CONST Null type=kotlin.Nothing value=null
+              arg1: CONST Null type=kotlin.Nothing? value=null
+            then: TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
+              typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
+              CONST Null type=kotlin.Nothing? value=null
           BRANCH
             if: CONST Boolean type=kotlin.Boolean value=true
             then: CALL '<set-value>(Int): Unit' type=kotlin.Unit origin=EQ
@@ -135,15 +137,15 @@ FILE fqName:<root> fileName:/safeCalls.kt
     VALUE_PARAMETER name:s index:0 type:kotlin.String? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test5(String?) on IHost: Int?'
-        BLOCK type=kotlin.Int origin=SAFE_CALL
+        BLOCK type=kotlin.Int? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.String? flags:val
             GET_VAR 'value-parameter s: String?' type=kotlin.String? origin=null
-          WHEN type=kotlin.Int origin=null
+          WHEN type=kotlin.Int? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL 'extLength() on String: Int' type=kotlin.Int origin=null
@@ -158,15 +160,15 @@ FILE fqName:<root> fileName:/safeCalls.kt
     BLOCK_BODY
       TYPE_OP type=kotlin.Unit origin=IMPLICIT_COERCION_TO_UNIT typeOperand=kotlin.Unit
         typeOperand: CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public flags: superTypes:[kotlin.Any]
-        BLOCK type=kotlin.Int origin=SAFE_CALL
+        BLOCK type=kotlin.Int? origin=SAFE_CALL
           VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.Int flags:val
             CONST Int type=kotlin.Int value=42
-          WHEN type=kotlin.Int origin=null
+          WHEN type=kotlin.Int? origin=null
             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
+                arg1: CONST Null type=kotlin.Nothing? value=null
+              then: CONST Null type=kotlin.Nothing? value=null
             BRANCH
               if: CONST Boolean type=kotlin.Boolean value=true
               then: CALL 'foo() on Int: Int' type=kotlin.Int origin=null
diff --git a/compiler/testData/ir/irText/expressions/variableAsFunctionCall.txt b/compiler/testData/ir/irText/expressions/variableAsFunctionCall.txt
index b5fc4ff4e82..36fe17fb4bb 100644
--- a/compiler/testData/ir/irText/expressions/variableAsFunctionCall.txt
+++ b/compiler/testData/ir/irText/expressions/variableAsFunctionCall.txt
@@ -32,29 +32,29 @@ FILE fqName:<root> fileName:/variableAsFunctionCall.kt
     VALUE_PARAMETER name:ns index:0 type:kotlin.String? flags:
     BLOCK_BODY
       RETURN type=kotlin.Nothing from='test4(String?): String?'
-        BLOCK type=kotlin.String origin=SAFE_CALL
-          VAR IR_TEMPORARY_VARIABLE name:tmp1_safe_receiver type:() -> kotlin.String flags:val
-            BLOCK type=() -> kotlin.String origin=SAFE_CALL
+        BLOCK type=kotlin.String? origin=SAFE_CALL
+          VAR IR_TEMPORARY_VARIABLE name:tmp1_safe_receiver type:(() -> kotlin.String)? flags:val
+            BLOCK type=(() -> kotlin.String)? origin=SAFE_CALL
               VAR IR_TEMPORARY_VARIABLE name:tmp0_safe_receiver type:kotlin.String? flags:val
                 GET_VAR 'value-parameter ns: String?' type=kotlin.String? origin=null
-              WHEN type=() -> kotlin.String origin=null
+              WHEN type=(() -> kotlin.String)? origin=null
                 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
+                    arg1: CONST Null type=kotlin.Nothing? value=null
+                  then: CONST Null type=kotlin.Nothing? value=null
                 BRANCH
                   if: CONST Boolean type=kotlin.Boolean value=true
                   then: CALL 'k() on String: () -> String' type=() -> kotlin.String origin=null
                     $receiver: GET_VAR 'tmp0_safe_receiver: String?' type=kotlin.String? origin=null
-          WHEN type=kotlin.String origin=null
+          WHEN type=kotlin.String? origin=null
             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
+                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
             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
+                $this: GET_VAR 'tmp1_safe_receiver: (() -> String)?' type=(() -> kotlin.String)? origin=null