[FIR] Support assignment operators

compiler/fir/psi2fir/src/org/jetbrains/kotlin/fir/builder/BaseFirBuilder.kt

@@ -475,6 +475,15 @@ abstract class BaseFirBuilder<T>(val session: FirSession, val context: Context =
                 }
             }
         }
+
+        if (operation in FirOperation.ASSIGNMENTS && operation != FirOperation.ASSIGN) {
+            return FirOperatorCallImpl(psi, operation).apply {
+                // TODO: take good psi
+                arguments += this@generateAssignment?.convert() ?: FirErrorExpressionImpl(null, "Unsupported left value of assignment: ${psi?.text}")
+                arguments += value
+            }
+        }
+
         return FirVariableAssignmentImpl(psi, false, value, operation).apply {
             lValue = initializeLValue(this@generateAssignment) { convert() as? FirQualifiedAccess }
         }

compiler/fir/psi2fir/testData/rawBuilder/expressions/destructuring.txt

@@ -37,6 +37,6 @@ FILE: destructuring.kt
         lval <unary>: <implicit> = x#
         x# = R|<local>/<unary>|.inc#()
         R|<local>/<unary>|
-        y# *= Double(2.0)
+        *=(y#, Double(2.0))
         z# = String()
     }

compiler/fir/psi2fir/testData/rawBuilder/expressions/modifications.txt

@@ -1,14 +1,14 @@
 FILE: modifications.kt
     public? final? fun simple(): kotlin/Unit {
         lvar x: <implicit> = Int(10)
-        x# += Int(20)
-        x# -= Int(5)
-        x# /= Int(5)
-        x# *= Int(10)
+        +=(x#, Int(20))
+        -=(x#, Int(5))
+        /=(x#, Int(5))
+        *=(x#, Int(10))
     }
     public? final? fun List<String>.modify(): kotlin/Unit {
-        this# += String(Alpha)
-        this# += String(Omega)
+        +=(this#, String(Alpha))
+        +=(this#, String(Omega))
     }
     public? final? fun Any.modify(): kotlin/Unit {
         lval <complex-set>: <implicit> = (this# as List<Int>)

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/resolve/transformers/body/resolve/FirExpressionsResolveTransformer.kt

@@ -5,14 +5,16 @@
 
 package org.jetbrains.kotlin.fir.resolve.transformers.body.resolve
 
-import org.jetbrains.kotlin.contracts.description.InvocationKind
 import org.jetbrains.kotlin.fir.*
-import org.jetbrains.kotlin.fir.declarations.FirAnonymousFunction
 import org.jetbrains.kotlin.fir.expressions.*
+import org.jetbrains.kotlin.fir.expressions.impl.FirErrorExpressionImpl
 import org.jetbrains.kotlin.fir.expressions.impl.FirExpressionWithSmartcastImpl
+import org.jetbrains.kotlin.fir.expressions.impl.FirFunctionCallImpl
+import org.jetbrains.kotlin.fir.expressions.impl.FirVariableAssignmentImpl
 import org.jetbrains.kotlin.fir.references.FirDelegateFieldReference
 import org.jetbrains.kotlin.fir.references.FirResolvedNamedReference
 import org.jetbrains.kotlin.fir.references.FirSuperReference
+import org.jetbrains.kotlin.fir.references.impl.FirErrorNamedReferenceImpl
 import org.jetbrains.kotlin.fir.references.impl.FirExplicitThisReference
 import org.jetbrains.kotlin.fir.references.impl.FirSimpleNamedReference
 import org.jetbrains.kotlin.fir.render
@@ -27,6 +29,7 @@ import org.jetbrains.kotlin.fir.resolve.withNullability
 import org.jetbrains.kotlin.fir.resolvedTypeFromPrototype
 import org.jetbrains.kotlin.fir.scopes.impl.withReplacedConeType
 import org.jetbrains.kotlin.fir.symbols.StandardClassIds
+import org.jetbrains.kotlin.fir.symbols.impl.FirPropertySymbol
 import org.jetbrains.kotlin.fir.symbols.invoke
 import org.jetbrains.kotlin.fir.types.*
 import org.jetbrains.kotlin.fir.types.impl.ConeClassTypeImpl
@@ -34,11 +37,11 @@ import org.jetbrains.kotlin.fir.types.impl.FirErrorTypeRefImpl
 import org.jetbrains.kotlin.fir.types.impl.FirImplicitUnitTypeRef
 import org.jetbrains.kotlin.fir.types.impl.FirResolvedTypeRefImpl
 import org.jetbrains.kotlin.fir.visitors.CompositeTransformResult
-import org.jetbrains.kotlin.fir.visitors.FirTransformer
 import org.jetbrains.kotlin.fir.visitors.compose
 import org.jetbrains.kotlin.fir.visitors.transformSingle
 import org.jetbrains.kotlin.ir.expressions.IrConstKind
 import org.jetbrains.kotlin.name.ClassId
+import org.jetbrains.kotlin.name.Name
 
 class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransformer) : FirPartialBodyResolveTransformer(transformer) {
     private val callResolver: FirCallResolver get() = components.callResolver
@@ -187,6 +190,53 @@ class FirExpressionsResolveTransformer(transformer: FirBodyResolveTransformer) :
         } else {
             transformExpression(operatorCall, data).single
         } as FirOperatorCall
+
+        if (operatorCall.operation in FirOperation.ASSIGNMENTS) {
+            require(operatorCall.operation != FirOperation.ASSIGN)
+            @Suppress("NAME_SHADOWING")
+            val operatorCall = operatorCall.transformArguments(this, noExpectedType)
+            val (leftArgument, rightArgument) = operatorCall.arguments
+
+            fun createFunctionCall(name: Name) = FirFunctionCallImpl(operatorCall.psi).apply {
+                explicitReceiver = leftArgument
+                arguments += rightArgument
+                calleeReference = FirSimpleNamedReference(
+                    operatorCall.psi,
+                    name,
+                    candidateSymbol = null
+                )
+            }
+
+            // TODO: disable DataFlowAnalyzer for resolving that two calls
+            // x.plusAssign(y)
+            val assignmentOperatorName = FirOperationNameConventions.ASSIGNMENTS.getValue(operatorCall.operation)
+            val assignOperatorCall = createFunctionCall(assignmentOperatorName)
+            val resolvedAssignCall = assignOperatorCall.transformSingle(this, noExpectedType)
+            val assignCallReference = resolvedAssignCall.toResolvedCallableReference()
+            // x + y
+            val simpleOperatorName = FirOperationNameConventions.ASSIGNMENTS_TO_SIMPLE_OPERATOR.getValue(operatorCall.operation)
+            val simpleOperatorCall = createFunctionCall(simpleOperatorName)
+            val resolvedOperatorCall = simpleOperatorCall.transformSingle(this, noExpectedType)
+            val operatorCallReference = resolvedOperatorCall.toResolvedCallableReference()
+
+            val property = (leftArgument.toResolvedCallableSymbol() as? FirPropertySymbol)?.fir
+            return when {
+                operatorCallReference == null || property?.isVal == true -> resolvedAssignCall.compose()
+                assignCallReference == null -> {
+                    val assignment =
+                        FirVariableAssignmentImpl(operatorCall.psi, false, resolvedOperatorCall, FirOperation.ASSIGN).apply {
+                            lValue = (leftArgument as? FirQualifiedAccess)?.calleeReference
+                                ?: FirErrorNamedReferenceImpl(null, "Unresolved reference")
+                        }
+                    assignment.transform(transformer, noExpectedType)
+                }
+                else -> FirErrorExpressionImpl(
+                    operatorCall.psi,
+                    "Operator overload ambiguity. $assignmentOperatorName and $simpleOperatorName are compatible"
+                ).compose()
+            }
+        }
+
         dataFlowAnalyzer.exitOperatorCall(result)
         return result.compose()
     }

compiler/fir/resolve/testData/resolve/expresssions/operators/plus.kt

@@ -0,0 +1,14 @@
+class Foo {
+    operator fun plus(other: Foo): Foo = this
+}
+
+fun test_1() {
+    val f1 = Foo()
+    val f2 = Foo()
+    val f3 = f1 + f2
+}
+
+fun test_2() {
+    var f = Foo()
+    f += Foo()
+}

compiler/fir/resolve/testData/resolve/expresssions/operators/plus.txt

@@ -0,0 +1,20 @@
+FILE: plus.kt
+    public final class Foo : R|kotlin/Any| {
+        public constructor(): R|Foo| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final operator fun plus(other: R|Foo|): R|Foo| {
+            ^plus this@R|/Foo|
+        }
+
+    }
+    public final fun test_1(): R|kotlin/Unit| {
+        lval f1: R|Foo| = R|/Foo.Foo|()
+        lval f2: R|Foo| = R|/Foo.Foo|()
+        lval f3: R|Foo| = R|<local>/f1|.R|/Foo.plus|(R|<local>/f2|)
+    }
+    public final fun test_2(): R|kotlin/Unit| {
+        lvar f: R|Foo| = R|/Foo.Foo|()
+        R|<local>/f| = R|<local>/f|.R|/Foo.plus|(R|/Foo.Foo|())
+    }

compiler/fir/resolve/testData/resolve/expresssions/operators/plusAndPlusAssign.kt

@@ -0,0 +1,9 @@
+class Foo {
+    operator fun plus(f: Foo): Foo {}
+    operator fun plusAssign(f: Foo) {}
+}
+
+fun test() {
+    var f = Foo()
+    f += f
+}

compiler/fir/resolve/testData/resolve/expresssions/operators/plusAndPlusAssign.txt

@@ -0,0 +1,17 @@
+FILE: plusAndPlusAssign.kt
+    public final class Foo : R|kotlin/Any| {
+        public constructor(): R|Foo| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final operator fun plus(f: R|Foo|): R|Foo| {
+        }
+
+        public final operator fun plusAssign(f: R|Foo|): R|kotlin/Unit| {
+        }
+
+    }
+    public final fun test(): R|kotlin/Unit| {
+        lvar f: R|Foo| = R|/Foo.Foo|()
+        ERROR_EXPR(Operator overload ambiguity. plusAssign and plus are compatible)
+    }

compiler/fir/resolve/testData/resolve/expresssions/operators/plusAssign.kt

@@ -0,0 +1,22 @@
+operator fun Foo.plusAssign(x: Any) {}
+
+class Foo {
+    operator fun plusAssign(x: Foo) {}
+    operator fun plusAssign(x: String) {}
+}
+
+fun test_1() {
+    val f = Foo()
+    f + f
+}
+
+fun test_2() {
+    val f = Foo()
+    f += f
+}
+
+fun test_3(f: Foo) {
+    f += f
+    f += ""
+    f += 1
+}

compiler/fir/resolve/testData/resolve/expresssions/operators/plusAssign.txt

@@ -0,0 +1,28 @@
+FILE: plusAssign.kt
+    public final operator fun R|Foo|.plusAssign(x: R|kotlin/Any|): R|kotlin/Unit| {
+    }
+    public final class Foo : R|kotlin/Any| {
+        public constructor(): R|Foo| {
+            super<R|kotlin/Any|>()
+        }
+
+        public final operator fun plusAssign(x: R|Foo|): R|kotlin/Unit| {
+        }
+
+        public final operator fun plusAssign(x: R|kotlin/String|): R|kotlin/Unit| {
+        }
+
+    }
+    public final fun test_1(): R|kotlin/Unit| {
+        lval f: R|Foo| = R|/Foo.Foo|()
+        R|<local>/f|.<Unresolved name: plus>#(R|<local>/f|)
+    }
+    public final fun test_2(): R|kotlin/Unit| {
+        lval f: R|Foo| = R|/Foo.Foo|()
+        R|<local>/f|.R|/Foo.plusAssign|(R|<local>/f|)
+    }
+    public final fun test_3(f: R|Foo|): R|kotlin/Unit| {
+        R|<local>/f|.R|/Foo.plusAssign|(R|<local>/f|)
+        R|<local>/f|.R|/Foo.plusAssign|(String())
+        R|<local>/f|.R|/plusAssign|(Int(1))
+    }

compiler/fir/resolve/testData/resolve/fib.txt

@@ -13,7 +13,7 @@ FILE: fib.kt
         while(R|<local>/<iterator>|.R|kotlin/collections/Iterator.hasNext|()) {
             lval i: R|kotlin/Int| = R|<local>/<iterator>|.R|kotlin/collections/IntIterator.next|()
             lval temp: R|kotlin/Int| = R|<local>/current|
-            R|<local>/current| += R|<local>/prev|
+            R|<local>/current| = R|<local>/current|.R|kotlin/Int.plus|(R|<local>/prev|)
             R|<local>/prev| = R|<local>/temp|
         }
 

compiler/fir/resolve/tests/org/jetbrains/kotlin/fir/FirResolveTestCaseGenerated.java

@@ -476,6 +476,34 @@ public class FirResolveTestCaseGenerated extends AbstractFirResolveTestCase {
                 runTest("compiler/fir/resolve/testData/resolve/expresssions/invoke/threeReceivers.kt");
             }
         }
+
+        @TestMetadata("compiler/fir/resolve/testData/resolve/expresssions/operators")
+        @TestDataPath("$PROJECT_ROOT")
+        @RunWith(JUnit3RunnerWithInners.class)
+        public static class Operators extends AbstractFirResolveTestCase {
+            private void runTest(String testDataFilePath) throws Exception {
+                KotlinTestUtils.runTest(this::doTest, this, testDataFilePath);
+            }
+
+            public void testAllFilesPresentInOperators() throws Exception {
+                KotlinTestUtils.assertAllTestsPresentByMetadata(this.getClass(), new File("compiler/fir/resolve/testData/resolve/expresssions/operators"), Pattern.compile("^([^.]+)\\.kt$"), true);
+            }
+
+            @TestMetadata("plus.kt")
+            public void testPlus() throws Exception {
+                runTest("compiler/fir/resolve/testData/resolve/expresssions/operators/plus.kt");
+            }
+
+            @TestMetadata("plusAndPlusAssign.kt")
+            public void testPlusAndPlusAssign() throws Exception {
+                runTest("compiler/fir/resolve/testData/resolve/expresssions/operators/plusAndPlusAssign.kt");
+            }
+
+            @TestMetadata("plusAssign.kt")
+            public void testPlusAssign() throws Exception {
+                runTest("compiler/fir/resolve/testData/resolve/expresssions/operators/plusAssign.kt");
+            }
+        }
     }
 
     @TestMetadata("compiler/fir/resolve/testData/resolve/fromBuilder")

compiler/fir/tree/src/org/jetbrains/kotlin/fir/expressions/FirOperation.kt

@@ -5,6 +5,8 @@
 
 package org.jetbrains.kotlin.fir.expressions
 
+import org.jetbrains.kotlin.name.Name
+import org.jetbrains.kotlin.util.OperatorNameConventions
 import java.util.*
 
 enum class FirOperation(val operator: String = "???") {
@@ -46,4 +48,26 @@ enum class FirOperation(val operator: String = "???") {
 
         val TYPES: Set<FirOperation> = EnumSet.of(IS, NOT_IS, AS, SAFE_AS)
     }
+}
+
+object FirOperationNameConventions {
+    val ASSIGNMENTS: Map<FirOperation, Name> = EnumMap(
+        mapOf(
+            FirOperation.PLUS_ASSIGN to OperatorNameConventions.PLUS_ASSIGN,
+            FirOperation.MINUS_ASSIGN to OperatorNameConventions.MINUS_ASSIGN,
+            FirOperation.TIMES_ASSIGN to OperatorNameConventions.TIMES_ASSIGN,
+            FirOperation.DIV_ASSIGN to OperatorNameConventions.DIV_ASSIGN,
+            FirOperation.REM_ASSIGN to OperatorNameConventions.REM_ASSIGN
+        )
+    )
+
+    val ASSIGNMENTS_TO_SIMPLE_OPERATOR: Map<FirOperation, Name> = EnumMap(
+        mapOf(
+            FirOperation.PLUS_ASSIGN to OperatorNameConventions.PLUS,
+            FirOperation.MINUS_ASSIGN to OperatorNameConventions.MINUS,
+            FirOperation.TIMES_ASSIGN to OperatorNameConventions.TIMES,
+            FirOperation.DIV_ASSIGN to OperatorNameConventions.DIV,
+            FirOperation.REM_ASSIGN to OperatorNameConventions.REM
+        )
+    )
 }

compiler/testData/ir/irText/declarations/localDelegatedProperties.fir.txt

@@ -14,5 +14,6 @@ FILE fqName:<root> fileName:/localDelegatedProperties.kt
       SET_VAR 'var x: IrErrorType [var] declared in <root>.test2' type=IrErrorType origin=null
         ERROR_CALL 'Unresolved reference: <Ambiguity: inc, [kotlin/inc, kotlin/inc]>#' type=IrErrorType
       GET_VAR 'val <unary>: IrErrorType [val] declared in <root>.test2' type=IrErrorType origin=null
-      SET_VAR 'var x: IrErrorType [var] declared in <root>.test2' type=IrErrorType origin=null
-        CONST Int type=IrErrorType value=1
+      CALL 'public final fun plusAssign (element: T of <uninitialized parent>): kotlin.Unit [inline] declared in kotlin.collections' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'var x: IrErrorType [var] declared in <root>.test2' type=IrErrorType origin=null
+        element: CONST Int type=kotlin.Int value=1

compiler/testData/ir/irText/expressions/augmentedAssignment1.fir.txt

@@ -19,24 +19,44 @@ FILE fqName:<root> fileName:/augmentedAssignment1.kt
       VAR name:x type:kotlin.Int [var]
         CONST Int type=kotlin.Int value=0
       SET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
-        CONST Int type=kotlin.Int value=1
+        CALL 'public final fun plus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: GET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=1
       SET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
-        CONST Int type=kotlin.Int value=2
+        CALL 'public final fun minus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: GET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=2
       SET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
-        CONST Int type=kotlin.Int value=3
+        CALL 'public final fun times (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: GET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=3
       SET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
-        CONST Int type=kotlin.Int value=4
+        CALL 'public final fun div (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: GET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=4
       SET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
-        CONST Int type=kotlin.Int value=5
+        CALL 'public final fun rem (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: GET_VAR 'var x: kotlin.Int [var] declared in <root>.testVariable' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=5
   FUN name:testProperty visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
       SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:kotlin.Int visibility:private [static]' type=kotlin.Unit origin=null
-        value: CONST Int type=kotlin.Int value=1
+        value: CALL 'public final fun plus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: CALL 'public final fun <get-p> (): kotlin.Int declared in <root>' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=1
       SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:kotlin.Int visibility:private [static]' type=kotlin.Unit origin=null
-        value: CONST Int type=kotlin.Int value=2
+        value: CALL 'public final fun minus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: CALL 'public final fun <get-p> (): kotlin.Int declared in <root>' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=2
       SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:kotlin.Int visibility:private [static]' type=kotlin.Unit origin=null
-        value: CONST Int type=kotlin.Int value=3
+        value: CALL 'public final fun times (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: CALL 'public final fun <get-p> (): kotlin.Int declared in <root>' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=3
       SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:kotlin.Int visibility:private [static]' type=kotlin.Unit origin=null
-        value: CONST Int type=kotlin.Int value=4
+        value: CALL 'public final fun div (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: CALL 'public final fun <get-p> (): kotlin.Int declared in <root>' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=4
       SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:kotlin.Int visibility:private [static]' type=kotlin.Unit origin=null
-        value: CONST Int type=kotlin.Int value=5
+        value: CALL 'public final fun rem (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+          $this: CALL 'public final fun <get-p> (): kotlin.Int declared in <root>' type=kotlin.Int origin=null
+          other: CONST Int type=kotlin.Int value=5

compiler/testData/ir/irText/expressions/augmentedAssignment2.fir.txt

@@ -51,25 +51,35 @@ FILE fqName:<root> fileName:/augmentedAssignment2.kt
     BLOCK_BODY
       VAR name:a type:<root>.A [val]
         CONSTRUCTOR_CALL 'public constructor <init> () [primary] declared in <root>.A' type=<root>.A origin=null
-      SET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
-        CONST String type=<root>.A value="+="
-      SET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
-        CONST String type=<root>.A value="-="
-      SET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
-        CONST String type=<root>.A value="*="
-      SET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
-        CONST String type=<root>.A value="/="
-      SET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
-        CONST String type=<root>.A value="*="
+      CALL 'public final fun plusAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="+="
+      CALL 'public final fun minusAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="-="
+      CALL 'public final fun timesAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="*="
+      CALL 'public final fun divAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="/="
+      CALL 'public final fun remAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'val a: <root>.A [val] declared in <root>.testVariable' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="*="
   FUN name:testProperty visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
-      SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:<root>.A visibility:private [final,static]' type=kotlin.Unit origin=null
-        value: CONST String type=<root>.A value="+="
-      SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:<root>.A visibility:private [final,static]' type=kotlin.Unit origin=null
-        value: CONST String type=<root>.A value="-="
-      SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:<root>.A visibility:private [final,static]' type=kotlin.Unit origin=null
-        value: CONST String type=<root>.A value="*="
-      SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:<root>.A visibility:private [final,static]' type=kotlin.Unit origin=null
-        value: CONST String type=<root>.A value="/="
-      SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:p type:<root>.A visibility:private [final,static]' type=kotlin.Unit origin=null
-        value: CONST String type=<root>.A value="%="
+      CALL 'public final fun plusAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: CALL 'public final fun <get-p> (): <root>.A declared in <root>' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="+="
+      CALL 'public final fun minusAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: CALL 'public final fun <get-p> (): <root>.A declared in <root>' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="-="
+      CALL 'public final fun timesAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: CALL 'public final fun <get-p> (): <root>.A declared in <root>' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="*="
+      CALL 'public final fun divAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: CALL 'public final fun <get-p> (): <root>.A declared in <root>' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="/="
+      CALL 'public final fun remAssign (s: kotlin.String): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: CALL 'public final fun <get-p> (): <root>.A declared in <root>' type=<root>.A origin=null
+        s: CONST String type=kotlin.String value="%="

compiler/testData/ir/irText/expressions/augmentedAssignmentWithExpression.fir.txt

@@ -12,7 +12,9 @@ FILE fqName:<root> fileName:/augmentedAssignmentWithExpression.kt
     FUN name:test1 visibility:public modality:FINAL <> ($this:<root>.Host) returnType:kotlin.Unit
       $this: VALUE_PARAMETER name:<this> type:<root>.Host
       BLOCK_BODY
-        ERROR_CALL 'Unresolved reference: this#' type=IrErrorType
+        CALL 'public final fun plusAssign (x: kotlin.Int): kotlin.Unit declared in <root>.Host' type=kotlin.Unit origin=null
+          $this: GET_VAR '<this>: <root>.Host declared in <root>.Host' type=<root>.Host origin=null
+          x: CONST Int type=kotlin.Int value=1
     FUN FAKE_OVERRIDE name:equals visibility:public modality:OPEN <> ($this:kotlin.Any, other:kotlin.Any?) returnType:kotlin.Boolean
       overridden:
         public open fun equals (other: kotlin.Any?): kotlin.Boolean declared in kotlin.Any
@@ -33,7 +35,9 @@ FILE fqName:<root> fileName:/augmentedAssignmentWithExpression.kt
   FUN name:test2 visibility:public modality:FINAL <> ($receiver:<root>.Host) returnType:kotlin.Unit
     $receiver: VALUE_PARAMETER name:<this> type:<root>.Host
     BLOCK_BODY
-      ERROR_CALL 'Unresolved reference: this#' type=IrErrorType
+      CALL 'public final fun plusAssign (x: kotlin.Int): kotlin.Unit declared in <root>.Host' type=kotlin.Unit origin=null
+        $this: GET_VAR '<this>: <root>.Host declared in <root>.test2' type=<root>.Host origin=null
+        x: CONST Int type=kotlin.Int value=1
   FUN name:test3 visibility:public modality:FINAL <> () returnType:kotlin.Unit
     BLOCK_BODY
       VAR name:<complex-set> type:<root>.Host [val]

compiler/testData/ir/irText/expressions/breakContinueInWhen.fir.txt

@@ -122,9 +122,11 @@ FILE fqName:<root> fileName:/breakContinueInWhen.kt
                 arg1: CONST Int type=kotlin.Int value=2
               then: CONTINUE label=null loop.label=null
           SET_VAR 'var s: kotlin.String [var] declared in <root>.testContinueDoWhile' type=kotlin.String origin=null
-            STRING_CONCATENATION type=kotlin.String
-              GET_VAR 'var k: kotlin.Int [var] declared in <root>.testContinueDoWhile' type=kotlin.Int origin=null
-              CONST String type=kotlin.String value=";"
+            CALL 'public final fun plus (other: kotlin.Any?): kotlin.String declared in kotlin.String' type=kotlin.String origin=null
+              $this: GET_VAR 'var s: kotlin.String [var] declared in <root>.testContinueDoWhile' type=kotlin.String origin=null
+              other: STRING_CONCATENATION type=kotlin.String
+                GET_VAR 'var k: kotlin.Int [var] declared in <root>.testContinueDoWhile' type=kotlin.Int origin=null
+                CONST String type=kotlin.String value=";"
         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 k: kotlin.Int [var] declared in <root>.testContinueDoWhile' type=kotlin.Int origin=null
           arg1: CONST Int type=kotlin.Int value=10

compiler/testData/ir/irText/expressions/complexAugmentedAssignment.fir.txt

@@ -219,9 +219,11 @@ FILE fqName:<root> fileName:/complexAugmentedAssignment.kt
       VALUE_PARAMETER name:b index:0 type:<root>.B
       BLOCK_BODY
         SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:s type:kotlin.Int visibility:private' type=kotlin.Unit origin=null
-          receiver: GET_VAR '<this>: <root>.B declared in <root>.Host.plusAssign' type=<root>.B origin=null
-          value: CALL 'public final fun <get-s> (): kotlin.Int declared in <root>.B' type=kotlin.Int origin=null
-            $this: GET_VAR 'b: <root>.B declared in <root>.Host.plusAssign' type=<root>.B origin=null
+          value: CALL 'public final fun plus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+            $this: CALL 'public final fun <get-s> (): kotlin.Int declared in <root>.B' type=kotlin.Int origin=null
+              $this: GET_VAR '<this>: <root>.B declared in <root>.Host.plusAssign' type=<root>.B origin=null
+            other: CALL 'public final fun <get-s> (): kotlin.Int declared in <root>.B' type=kotlin.Int origin=null
+              $this: GET_VAR 'b: <root>.B declared in <root>.Host.plusAssign' type=<root>.B origin=null
     FUN FAKE_OVERRIDE name:equals visibility:public modality:OPEN <> ($this:kotlin.Any, other:kotlin.Any?) returnType:kotlin.Boolean
       overridden:
         public open fun equals (other: kotlin.Any?): kotlin.Boolean declared in kotlin.Any
@@ -239,4 +241,7 @@ FILE fqName:<root> fileName:/complexAugmentedAssignment.kt
     $receiver: VALUE_PARAMETER name:<this> type:<root>.Host
     VALUE_PARAMETER name:v index:0 type:<root>.B
     BLOCK_BODY
-      ERROR_CALL 'Unresolved reference: R|<local>/v|' type=IrErrorType
+      CALL 'public final fun plusAssign (b: <root>.B): kotlin.Unit declared in <root>.Host' type=kotlin.Unit origin=null
+        $this: GET_VAR '<this>: <root>.Host declared in <root>.Host' type=<root>.Host origin=null
+        b: CONSTRUCTOR_CALL 'public constructor <init> (s: kotlin.Int) [primary] declared in <root>.B' type=<root>.B origin=null
+          s: CONST Int type=kotlin.Int value=1000

compiler/testData/ir/irText/expressions/field.fir.txt

@@ -28,4 +28,6 @@ FILE fqName:<root> fileName:/field.kt
       VALUE_PARAMETER name:value index:0 type:kotlin.Int
       BLOCK_BODY
         SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:testAugmented type:kotlin.Int visibility:private [static]' type=kotlin.Unit origin=null
-          value: GET_VAR 'value: kotlin.Int declared in <root>.<set-testAugmented>' type=kotlin.Int origin=null
+          value: CALL 'public final fun plus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+            $this: GET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:testAugmented type:kotlin.Int visibility:private [static]' type=kotlin.Int origin=GET_PROPERTY
+            other: GET_VAR 'value: kotlin.Int declared in <root>.<set-testAugmented>' type=kotlin.Int origin=null

compiler/testData/ir/irText/expressions/kt16904.fir.txt

@@ -75,12 +75,15 @@ FILE fqName:<root> fileName:/kt16904.kt
     $this: VALUE_PARAMETER INSTANCE_RECEIVER name:<this> type:<root>.Test1
     CONSTRUCTOR visibility:public <> () returnType:<root>.Test1
       BLOCK_BODY
-        SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:x type:<root>.B visibility:private [final]' type=kotlin.Unit origin=null
-          receiver: GET_VAR '<this>: <root>.A declared in <root>.A' type=<root>.A origin=null
-          value: CONST Int type=<root>.B value=42
+        CALL 'public final fun plusAssign (x: kotlin.Int): kotlin.Unit declared in <root>.B' type=kotlin.Unit origin=null
+          $this: CALL 'public final fun <get-x> (): <root>.B declared in <root>.A' type=<root>.B origin=null
+            $this: GET_VAR '<this>: <root>.A declared in <root>.A' type=<root>.A origin=null
+          x: CONST Int type=kotlin.Int value=42
         SET_FIELD 'FIELD PROPERTY_BACKING_FIELD name:y type:kotlin.Int visibility:private' type=kotlin.Unit origin=null
-          receiver: GET_VAR '<this>: <root>.A declared in <root>.A' type=<root>.A origin=null
-          value: CONST Int type=kotlin.Int value=42
+          value: CALL 'public final fun plus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+            $this: CALL 'public final fun <get-y> (): kotlin.Int declared in <root>.A' type=kotlin.Int origin=null
+              $this: GET_VAR '<this>: <root>.A declared in <root>.A' type=<root>.A origin=null
+            other: CONST Int type=kotlin.Int value=42
         DELEGATING_CONSTRUCTOR_CALL 'public constructor <init> () [primary] declared in kotlin.Any'
         INSTANCE_INITIALIZER_CALL classDescriptor='CLASS CLASS name:Test1 modality:FINAL visibility:public superTypes:[<root>.A]'
     PROPERTY FAKE_OVERRIDE name:x visibility:public modality:FINAL [val]

compiler/testData/ir/irText/expressions/kt24804.fir.txt

@@ -12,7 +12,9 @@ FILE fqName:<root> fileName:/kt24804.kt
       DO_WHILE label=l2 origin=DO_WHILE_LOOP
         body: BLOCK type=kotlin.Unit origin=null
           SET_VAR 'var z: kotlin.Int [var] declared in <root>.run' type=kotlin.Int origin=null
-            CONST Int type=kotlin.Int value=1
+            CALL 'public final fun plus (other: kotlin.Int): kotlin.Int declared in kotlin.Int' type=kotlin.Int origin=null
+              $this: GET_VAR 'var z: kotlin.Int [var] declared in <root>.run' type=kotlin.Int origin=null
+              other: CONST Int type=kotlin.Int value=1
           WHEN type=kotlin.Unit origin=IF
             BRANCH
               if: CALL 'public final fun greater (arg0: kotlin.Int, arg1: kotlin.Int): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=GT

compiler/testData/ir/irText/expressions/kt27933.fir.txt

@@ -14,7 +14,9 @@ FILE fqName:<root> fileName:/kt27933.kt
           if: CONST Boolean type=kotlin.Boolean value=true
           then: BLOCK type=kotlin.Unit origin=null
             SET_VAR 'var r: kotlin.String [var] declared in <root>.box' type=kotlin.String origin=null
-              CONST String type=kotlin.String value="O"
+              CALL 'public final fun plus (other: kotlin.Any?): kotlin.String declared in kotlin.String' type=kotlin.String origin=null
+                $this: GET_VAR 'var r: kotlin.String [var] declared in <root>.box' type=kotlin.String origin=null
+                other: CONST String type=kotlin.String value="O"
       WHEN type=kotlin.Unit origin=IF
         BRANCH
           if: CALL 'public final fun EQEQ (arg0: kotlin.Any?, arg1: kotlin.Any?): kotlin.Boolean declared in kotlin.internal.ir' type=kotlin.Boolean origin=EQEQ
@@ -22,6 +24,8 @@ FILE fqName:<root> fileName:/kt27933.kt
             arg1: CONST String type=kotlin.String value="O"
           then: BLOCK type=kotlin.Unit origin=null
             SET_VAR 'var r: kotlin.String [var] declared in <root>.box' type=kotlin.String origin=null
-              CONST String type=kotlin.String value="K"
+              CALL 'public final fun plus (other: kotlin.Any?): kotlin.String declared in kotlin.String' type=kotlin.String origin=null
+                $this: GET_VAR 'var r: kotlin.String [var] declared in <root>.box' type=kotlin.String origin=null
+                other: CONST String type=kotlin.String value="K"
       RETURN type=kotlin.Nothing from='public final fun box (): kotlin.String declared in <root>'
         GET_VAR 'var r: kotlin.String [var] declared in <root>.box' type=kotlin.String origin=null

compiler/testData/ir/irText/expressions/kt30020.fir.txt

@@ -24,7 +24,10 @@ FILE fqName:<root> fileName:/kt30020.kt
     VALUE_PARAMETER name:x index:0 type:<root>.X
     VALUE_PARAMETER name:nx index:1 type:<root>.X?
     BLOCK_BODY
-      ERROR_CALL 'Unresolved reference: R|/X.xs|' type=IrErrorType
+      CALL 'public final fun plusAssign (element: T of <uninitialized parent>): kotlin.Unit [inline] declared in kotlin.collections' type=kotlin.Unit origin=null
+        $receiver: CALL 'public abstract fun <get-xs> (): kotlin.collections.MutableList<kotlin.Any> declared in <root>.X' type=kotlin.collections.MutableList<kotlin.Any> origin=null
+          $this: GET_VAR 'x: <root>.X declared in <root>.test' type=<root>.X origin=null
+        element: CONST Int type=kotlin.Int value=1
       VAR name:<complex-set> type:kotlin.collections.MutableList<kotlin.Any> [val]
         CALL 'public abstract fun f (): kotlin.collections.MutableList<kotlin.Any> declared in <root>.X' type=kotlin.collections.MutableList<kotlin.Any> origin=null
           $this: GET_VAR 'x: <root>.X declared in <root>.test' type=<root>.X origin=null
@@ -79,7 +82,7 @@ FILE fqName:<root> fileName:/kt30020.kt
   FUN name:testExtensionReceiver visibility:public modality:FINAL <> ($receiver:kotlin.collections.MutableList<kotlin.Any>) returnType:kotlin.Unit
     $receiver: VALUE_PARAMETER name:<this> type:kotlin.collections.MutableList<kotlin.Any>
     BLOCK_BODY
-      ERROR_CALL 'Unresolved reference: this#' type=IrErrorType
+      ERROR_EXPR 'Operator overload ambiguity. plusAssign and plus are compatible' type=IrErrorType
   CLASS CLASS name:AML modality:ABSTRACT visibility:public superTypes:[kotlin.collections.MutableList<kotlin.Int>]
     $this: VALUE_PARAMETER INSTANCE_RECEIVER name:<this> type:<root>.AML
     CONSTRUCTOR visibility:public <> () returnType:<root>.AML [primary]
@@ -89,7 +92,7 @@ FILE fqName:<root> fileName:/kt30020.kt
     FUN name:testExplicitThis visibility:public modality:FINAL <> ($this:<root>.AML) returnType:kotlin.Unit
       $this: VALUE_PARAMETER name:<this> type:<root>.AML
       BLOCK_BODY
-        ERROR_CALL 'Unresolved reference: this#' type=IrErrorType
+        ERROR_EXPR 'Operator overload ambiguity. plusAssign and plus are compatible' type=IrErrorType
     CLASS CLASS name:Inner modality:FINAL visibility:public [inner] superTypes:[kotlin.Any]
       $this: VALUE_PARAMETER INSTANCE_RECEIVER name:<this> type:<root>.AML.Inner
       CONSTRUCTOR visibility:public <> () returnType:<root>.AML.Inner [primary]
@@ -99,7 +102,7 @@ FILE fqName:<root> fileName:/kt30020.kt
       FUN name:testOuterThis visibility:public modality:FINAL <> ($this:<root>.AML.Inner) returnType:kotlin.Unit
         $this: VALUE_PARAMETER name:<this> type:<root>.AML.Inner
         BLOCK_BODY
-          ERROR_CALL 'Unresolved reference: this@AML#' type=IrErrorType
+          ERROR_EXPR 'Operator overload ambiguity. plusAssign and plus are compatible' type=IrErrorType
       FUN FAKE_OVERRIDE name:equals visibility:public modality:OPEN <> ($this:kotlin.Any, other:kotlin.Any?) returnType:kotlin.Boolean
         overridden:
           public open fun equals (other: kotlin.Any?): kotlin.Boolean declared in kotlin.Any

compiler/testData/ir/irText/expressions/lambdaInCAO.fir.txt

@@ -17,7 +17,12 @@ FILE fqName:<root> fileName:/lambdaInCAO.kt
   FUN name:test1 visibility:public modality:FINAL <> (a:kotlin.Any) returnType:kotlin.Unit
     VALUE_PARAMETER name:a index:0 type:kotlin.Any
     BLOCK_BODY
-      ERROR_CALL 'Unresolved reference: R|<local>/a|' type=IrErrorType
+      CALL 'public final fun plusAssign (lambda: kotlin.Function0<kotlin.Unit>): kotlin.Unit declared in <root>' type=kotlin.Unit origin=null
+        $receiver: GET_VAR 'a: kotlin.Any declared in <root>.test1' type=kotlin.Any origin=null
+        lambda: FUN_EXPR type=kotlin.Function0<kotlin.Unit> origin=LAMBDA
+          FUN LOCAL_FUNCTION_FOR_LAMBDA name:<anonymous> visibility:local modality:FINAL <> () returnType:kotlin.Unit
+            BLOCK_BODY
+              GET_OBJECT 'CLASS IR_EXTERNAL_DECLARATION_STUB OBJECT name:Unit modality:FINAL visibility:public superTypes:[kotlin.Any]' type=kotlin.Unit
   FUN name:test2 visibility:public modality:FINAL <> (a:kotlin.Any) returnType:kotlin.Unit
     VALUE_PARAMETER name:a index:0 type:kotlin.Any
     BLOCK_BODY

compiler/testData/ir/irText/expressions/sam/samOperators.fir.txt

@@ -26,5 +26,9 @@ FILE fqName:<root> fileName:/samOperators.kt
   FUN name:test3 visibility:public modality:FINAL <> ($receiver:<root>.J) returnType:kotlin.Unit
     $receiver: VALUE_PARAMETER name:<this> type:<root>.J
     BLOCK_BODY
-      ERROR_CALL 'Unresolved reference: this#' type=IrErrorType
-      ERROR_CALL 'Unresolved reference: this#' type=IrErrorType
+      CALL 'public open fun plusAssign (i: java.lang.Runnable?): kotlin.Unit declared in <root>.J' type=kotlin.Unit origin=null
+        $this: GET_VAR '<this>: <root>.J declared in <root>.test3' type=<root>.J origin=null
+        i: ERROR_CALL 'Unsupported callable reference: ::<Unresolved name: f>#' type=IrErrorType
+      CALL 'public open fun minusAssign (i: java.lang.Runnable?): kotlin.Unit declared in <root>.J' type=kotlin.Unit origin=null
+        $this: GET_VAR '<this>: <root>.J declared in <root>.test3' type=<root>.J origin=null
+        i: ERROR_CALL 'Unsupported callable reference: ::<Unresolved name: f>#' type=IrErrorType