Descriptors in calls are substituted,

and symbols refer to the original descriptors.

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/builders/ExpressionHelpers.kt

@@ -135,7 +135,7 @@ fun IrBuilderWithScope.irNotEquals(arg1: IrExpression, arg2: IrExpression) =
                                   arg1, arg2))
 
 fun IrBuilderWithScope.irGet(receiver: IrExpression, getterSymbol: IrFunctionSymbol): IrCall =
-        IrGetterCallImpl(startOffset, endOffset, getterSymbol, null, receiver, null, IrStatementOrigin.GET_PROPERTY)
+        IrGetterCallImpl(startOffset, endOffset, getterSymbol, getterSymbol.descriptor, null, receiver, null, IrStatementOrigin.GET_PROPERTY)
 
 fun IrBuilderWithScope.irCall(callee: IrFunctionSymbol, type: KotlinType): IrCall =
         IrCallImpl(startOffset, endOffset, type, callee, callee.descriptor, null)

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

@@ -16,9 +16,10 @@
 
 package org.jetbrains.kotlin.ir.expressions.impl
 
-import org.jetbrains.kotlin.descriptors.*
+import org.jetbrains.kotlin.descriptors.ClassDescriptor
+import org.jetbrains.kotlin.descriptors.FunctionDescriptor
+import org.jetbrains.kotlin.descriptors.TypeParameterDescriptor
 import org.jetbrains.kotlin.ir.expressions.IrCall
-import org.jetbrains.kotlin.ir.expressions.IrCallWithShallowCopy
 import org.jetbrains.kotlin.ir.expressions.IrStatementOrigin
 import org.jetbrains.kotlin.ir.symbols.IrClassSymbol
 import org.jetbrains.kotlin.ir.symbols.IrFunctionSymbol
@@ -63,7 +64,7 @@ class IrCallImpl(
             typeArguments: Map<TypeParameterDescriptor, KotlinType>? = null,
             origin: IrStatementOrigin? = null,
             superQualifierSymbol: IrClassSymbol? = null
-    ) : this(startOffset, endOffset, symbol.descriptor.returnType!!, symbol, descriptor, typeArguments, origin, superQualifierSymbol)
+    ) : this(startOffset, endOffset, descriptor.returnType!!, symbol, descriptor, typeArguments, origin, superQualifierSymbol)
 
     constructor(startOffset: Int, endOffset: Int, symbol: IrFunctionSymbol) :
             this(startOffset, endOffset, symbol, symbol.descriptor)

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

@@ -36,11 +36,11 @@ import java.lang.UnsupportedOperationException
 abstract class IrPropertyAccessorCallBase(
         startOffset: Int, endOffset: Int,
         override val symbol: IrFunctionSymbol,
+        override val descriptor: FunctionDescriptor,
         typeArguments: Map<TypeParameterDescriptor, KotlinType>?,
         override val origin: IrStatementOrigin? = null,
         override val superQualifierSymbol: IrClassSymbol? = null
-) : IrMemberAccessExpressionBase(startOffset, endOffset, symbol.descriptor.returnType!!, typeArguments), IrCall {
-    override val descriptor: FunctionDescriptor get() = symbol.descriptor
+) : IrMemberAccessExpressionBase(startOffset, endOffset, descriptor.returnType!!, typeArguments), IrCall {
     override val superQualifier: ClassDescriptor? get() = superQualifierSymbol?.descriptor
 
     override fun <R, D> accept(visitor: IrElementVisitor<R, D>, data: D): R {
@@ -55,18 +55,20 @@ abstract class IrPropertyAccessorCallBase(
 class IrGetterCallImpl(
         startOffset: Int, endOffset: Int,
         symbol: IrFunctionSymbol,
+        descriptor: FunctionDescriptor,
         typeArguments: Map<TypeParameterDescriptor, KotlinType>?,
         origin: IrStatementOrigin? = null,
         superQualifierSymbol: IrClassSymbol? = null
-) : IrPropertyAccessorCallBase(startOffset, endOffset, symbol, typeArguments, origin, superQualifierSymbol), IrCallWithShallowCopy {
+) : IrPropertyAccessorCallBase(startOffset, endOffset, symbol, descriptor, typeArguments, origin, superQualifierSymbol), IrCallWithShallowCopy {
     constructor(startOffset: Int, endOffset: Int,
                 symbol: IrFunctionSymbol,
+                descriptor: FunctionDescriptor,
                 typeArguments: Map<TypeParameterDescriptor, KotlinType>?,
                 dispatchReceiver: IrExpression?,
                 extensionReceiver: IrExpression?,
                 origin: IrStatementOrigin? = null,
                 superQualifierSymbol: IrClassSymbol? = null
-    ) : this(startOffset, endOffset, symbol, typeArguments, origin, superQualifierSymbol) {
+    ) : this(startOffset, endOffset, symbol, descriptor, typeArguments, origin, superQualifierSymbol) {
         this.dispatchReceiver = dispatchReceiver
         this.extensionReceiver = extensionReceiver
     }
@@ -82,12 +84,15 @@ class IrGetterCallImpl(
     }
 
     override fun shallowCopy(newOrigin: IrStatementOrigin?, newCallee: IrFunctionSymbol, newSuperQualifier: IrClassSymbol?): IrCall =
-            IrGetterCallImpl(startOffset, endOffset, newCallee, typeArguments, dispatchReceiver, extensionReceiver, newOrigin, newSuperQualifier)
+            IrGetterCallImpl(startOffset, endOffset, newCallee,
+                             descriptor, // TODO substitute descriptor for new callee?
+                             typeArguments, dispatchReceiver, extensionReceiver, newOrigin, newSuperQualifier)
 
     override fun shallowCopy(newOrigin: IrStatementOrigin?, newCallee: FunctionDescriptor, newSuperQualifier: ClassDescriptor?): IrCall =
             IrGetterCallImpl(
                     startOffset, endOffset,
                     createFunctionSymbol(newCallee),
+                    newCallee,
                     typeArguments, dispatchReceiver, extensionReceiver,
                     newOrigin,
                     createClassSymbolOrNull(newSuperQualifier)
@@ -97,19 +102,21 @@ class IrGetterCallImpl(
 class IrSetterCallImpl(
         startOffset: Int, endOffset: Int,
         symbol: IrFunctionSymbol,
+        descriptor: FunctionDescriptor,
         typeArguments: Map<TypeParameterDescriptor, KotlinType>?,
         origin: IrStatementOrigin? = null,
         superQualifierSymbol: IrClassSymbol? = null
-) : IrPropertyAccessorCallBase(startOffset, endOffset, symbol, typeArguments, origin, superQualifierSymbol), IrCallWithShallowCopy {
+) : IrPropertyAccessorCallBase(startOffset, endOffset, symbol, descriptor, typeArguments, origin, superQualifierSymbol), IrCallWithShallowCopy {
     constructor(startOffset: Int, endOffset: Int,
                 symbol: IrFunctionSymbol,
+                descriptor: FunctionDescriptor,
                 typeArguments: Map<TypeParameterDescriptor, KotlinType>?,
                 dispatchReceiver: IrExpression?,
                 extensionReceiver: IrExpression?,
                 argument: IrExpression,
                 origin: IrStatementOrigin? = null,
                 superQualifierSymbol: IrClassSymbol? = null
-    ) : this(startOffset, endOffset, symbol, typeArguments, origin, superQualifierSymbol) {
+    ) : this(startOffset, endOffset, symbol, descriptor, typeArguments, origin, superQualifierSymbol) {
         this.dispatchReceiver = dispatchReceiver
         this.extensionReceiver = extensionReceiver
         putValueArgument(SETTER_ARGUMENT_INDEX, argument)
@@ -131,12 +138,15 @@ class IrSetterCallImpl(
     }
 
     override fun shallowCopy(newOrigin: IrStatementOrigin?, newCallee: IrFunctionSymbol, newSuperQualifier: IrClassSymbol?): IrCall =
-            IrSetterCallImpl(startOffset, endOffset, newCallee, typeArguments, newOrigin, newSuperQualifier)
+            IrSetterCallImpl(startOffset, endOffset, newCallee,
+                             descriptor, // TODO substitute newCallee.descriptor?
+                             typeArguments, newOrigin, newSuperQualifier)
 
     override fun shallowCopy(newOrigin: IrStatementOrigin?, newCallee: FunctionDescriptor, newSuperQualifier: ClassDescriptor?): IrCall =
             IrSetterCallImpl(
                     startOffset, endOffset,
                     createFunctionSymbol(newCallee),
+                    newCallee,
                     typeArguments,
                     newOrigin,
                     createClassSymbolOrNull(newSuperQualifier)

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/symbols/impl/IrSymbolBase.kt

@@ -24,6 +24,18 @@ abstract class IrSymbolBase<out D : DeclarationDescriptor>(override val descript
 
 abstract class IrBindableSymbolBase<out D : DeclarationDescriptor, B : IrSymbolOwner>(descriptor: D) :
         IrBindableSymbol<D, B>, IrSymbolBase<D>(descriptor) {
+    init {
+        assert(isOriginalDescriptor(descriptor)) {
+            "Substituted descriptor $descriptor for ${descriptor.original}"
+        }
+    }
+
+    private fun isOriginalDescriptor(descriptor: DeclarationDescriptor): Boolean =
+            if (descriptor is ValueParameterDescriptor)
+                isOriginalDescriptor(descriptor.containingDeclaration)
+            else
+                descriptor == descriptor.original
+
     private var _owner: B? = null
     override val owner: B
         get() = _owner ?: throw IllegalStateException("Symbol for $descriptor is unbound")