Drop unnecessary SubFrame creation from interpreter

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/InstructionsUnfolder.kt

@@ -46,10 +46,10 @@ internal fun unfoldInstruction(element: IrElement?, environment: IrInterpreterEn
         null -> return
         is IrSimpleFunction -> unfoldFunction(element, environment)
         is IrConstructor -> unfoldConstructor(element, callStack)
-        is IrCall -> unfoldCall(element, environment)
-        is IrConstructorCall -> unfoldConstructorCall(element, environment)
-        is IrEnumConstructorCall -> unfoldConstructorCall(element, environment)
-        is IrDelegatingConstructorCall -> unfoldConstructorCall(element, environment)
+        is IrCall -> unfoldValueParameters(element, callStack)
+        is IrConstructorCall -> unfoldValueParameters(element, callStack)
+        is IrEnumConstructorCall -> unfoldValueParameters(element, callStack)
+        is IrDelegatingConstructorCall -> unfoldValueParameters(element, callStack)
         is IrInstanceInitializerCall -> unfoldInstanceInitializerCall(element, callStack)
         is IrField -> unfoldField(element, callStack)
         is IrBody -> unfoldBody(element, callStack)
@@ -117,17 +117,7 @@ private fun unfoldConstructor(constructor: IrConstructor, callStack: CallStack)
     }
 }
 
-private fun unfoldCall(call: IrCall, environment: IrInterpreterEnvironment) {
-    unfoldValueParameters(call, environment)
-}
-
-// This function is responsible for IrConstructorCall, IrDelegatingConstructorCall and IrEnumConstructorCall
-private fun unfoldConstructorCall(constructorCall: IrFunctionAccessExpression, environment: IrInterpreterEnvironment) {
-    unfoldValueParameters(constructorCall, environment)
-}
-
-private fun unfoldValueParameters(expression: IrFunctionAccessExpression, environment: IrInterpreterEnvironment) {
-    val callStack = environment.callStack
+private fun unfoldValueParameters(expression: IrFunctionAccessExpression, callStack: CallStack) {
     val irFunction = expression.symbol.owner
 
     val hasDefaults = (0 until expression.valueArgumentsCount).any { expression.getValueArgument(it) == null }
@@ -245,8 +235,6 @@ private fun unfoldValueParameters(expression: IrFunctionAccessExpression, enviro
 
         callStack.addInstruction(CompoundInstruction(callToDefault))
     } else {
-        // new sub frame is used to store value arguments, in case then they are used in default args evaluation
-        callStack.newSubFrame(expression) // TODO drop
         callStack.addInstruction(SimpleInstruction(expression))
 
         fun IrValueParameter.schedule(arg: IrExpression?) {
@@ -433,7 +421,6 @@ private fun unfoldThrow(expression: IrThrow, callStack: CallStack) {
 
 private fun unfoldStringConcatenation(expression: IrStringConcatenation, environment: IrInterpreterEnvironment) {
     val callStack = environment.callStack
-    callStack.newSubFrame(expression)
     callStack.addInstruction(SimpleInstruction(expression))
 
     // this callback is used to check the need for an explicit toString call
@@ -453,7 +440,6 @@ private fun unfoldStringConcatenation(expression: IrStringConcatenation, environ
                     return callStack.pushState(result.toState(environment.irBuiltIns.stringType))
                 }
                 val toStringCall = state.createToStringIrCall()
-                callStack.newSubFrame(toStringCall)
                 callStack.addInstruction(SimpleInstruction(toStringCall))
                 callStack.pushState(state)
             }
@@ -475,7 +461,6 @@ private fun unfoldComposite(element: IrComposite, callStack: CallStack) {
 
 private fun unfoldFunctionReference(reference: IrFunctionReference, callStack: CallStack) {
     val function = reference.symbol.owner
-    callStack.newSubFrame(reference)
     callStack.addInstruction(SimpleInstruction(reference))
 
     reference.dispatchReceiver?.let { callStack.addInstruction(SimpleInstruction(function.dispatchReceiverParameter!!)) }
@@ -487,7 +472,6 @@ private fun unfoldFunctionReference(reference: IrFunctionReference, callStack: C
 
 private fun unfoldPropertyReference(propertyReference: IrPropertyReference, callStack: CallStack) {
     val getter = propertyReference.getter!!.owner
-    callStack.newSubFrame(propertyReference)
     callStack.addInstruction(SimpleInstruction(propertyReference))
 
     propertyReference.dispatchReceiver?.let { callStack.addInstruction(SimpleInstruction(getter.dispatchReceiverParameter!!)) }

compiler/ir/ir.interpreter/src/org/jetbrains/kotlin/ir/interpreter/IrInterpreter.kt

@@ -81,7 +81,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
     internal fun withNewCallStack(call: IrCall, init: IrInterpreter.() -> Any?): State {
         return with(IrInterpreter(environment.copyWithNewCallStack(), bodyMap)) {
             callStack.newFrame(call.symbol.owner)
-            callStack.newSubFrame(call)
             init()
 
             while (!callStack.hasNoInstructions()) {
@@ -159,8 +158,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
             IllegalArgumentException("Parameter specified as non-null is null: method $method, parameter $parameter")
         } ?: return
 
-        // outer classes can be used in default args evaluation
-        if (isReceiver() && state is Complex) state.loadOuterClassesInto(callStack)
         callStack.pushState(state)
     }
 
@@ -182,7 +179,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
         val irFunction = dispatchReceiver?.getIrFunctionByIrCall(call) ?: call.symbol.owner
         val args = listOfNotNull(dispatchReceiver.getThisOrSuperReceiver(irFunction), extensionReceiver) + valueArguments
 
-        callStack.dropSubFrame() // drop intermediate frame that contains variables for default arg evaluation
         callStack.newFrame(irFunction)
         callStack.addInstruction(SimpleInstruction(irFunction))
 
@@ -255,7 +251,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
         if (irClass.isLocal) callStack.storeUpValues(objectState as StateWithClosure)
         val outerClass = receiverSymbol?.let { callStack.popState() }
 
-        callStack.dropSubFrame()
         callStack.newFrame(constructor)
         callStack.addInstruction(SimpleInstruction(constructor))
         if (irClass.isLocal) callStack.loadUpValues(objectState as StateWithClosure)
@@ -291,7 +286,7 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
     }
 
     private fun interpretDelegatingConstructorCall(constructorCall: IrDelegatingConstructorCall) {
-        if (constructorCall.symbol.owner.parent == irBuiltIns.anyClass.owner) return callStack.dropSubFrame()
+        if (constructorCall.symbol.owner.parent == irBuiltIns.anyClass.owner) return
         interpretConstructorCall(constructorCall)
     }
 
@@ -588,7 +583,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
             }
         }
 
-        callStack.dropSubFrame()
         callStack.pushState(result.reversed().joinToString(separator = "").toState(expression.type))
     }
 
@@ -604,8 +598,6 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
         val dispatchReceiver = reference.dispatchReceiver?.let { callStack.popState() }
         val extensionReceiver = reference.extensionReceiver?.let { callStack.popState() }
 
-        callStack.dropSubFrame()
-
         val function = KFunctionState(
             reference,
             dispatchReceiver?.let { Variable(irFunction.getDispatchReceiver()!!, it) },
@@ -617,10 +609,7 @@ class IrInterpreter(internal val environment: IrInterpreterEnvironment, internal
 
     private fun interpretPropertyReference(propertyReference: IrPropertyReference) {
         // it is impossible to get KProperty2 through ::, so only one receiver can be not null (or both null)
-        val receiver = (propertyReference.dispatchReceiver ?: propertyReference.extensionReceiver)
-            ?.let { callStack.popState() }
-
-        callStack.dropSubFrame()
+        val receiver = (propertyReference.dispatchReceiver ?: propertyReference.extensionReceiver)?.let { callStack.popState() }
         val propertyState = KPropertyState(propertyReference, receiver)
 
         fun List<IrTypeParameter>.addToFields() {