[JS IR] store signatures for private symbols separately from public

Those signatures are used in JS IR IC

compiler/fir/fir2ir/src/org/jetbrains/kotlin/fir/symbols/Fir2IrBindableSymbol.kt

@@ -43,6 +43,8 @@ abstract class Fir2IrBindableSymbol<out D : DeclarationDescriptor, B : IrDeclara
     override val hasDescriptor: Boolean
         get() = false
 
+    override var privateSignature: IdSignature? = null
+
     override fun toString(): String {
         if (isBound) return owner.render()
         return "Unbound public symbol for $signature"

compiler/ir/ir.tree.impl/src/org/jetbrains/kotlin/ir/declarations/impl/IrFactoryImplForJsIC.kt

@@ -26,7 +26,7 @@ class IrFactoryImplForJsIC(override val stageController: StageController) : Abst
     }
 
     override fun declarationSignature(declaration: IrDeclaration): IdSignature? {
-        return declarationToSignature[declaration] ?: declaration.symbol.signature
+        return declarationToSignature[declaration] ?: declaration.symbol.signature ?: declaration.symbol.privateSignature
     }
 
     override fun createAnonymousInitializer(

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/symbols/IrDelegatingSymbol.kt

@@ -33,6 +33,12 @@ abstract class IrDelegatingSymbol<S : IrBindableSymbol<D, B>, B : IrSymbolOwner,
         if (delegate === other) return true
         return false
     }
+
+    override var privateSignature: IdSignature?
+        get() = delegate.privateSignature
+        set(value) {
+            delegate.privateSignature = value
+        }
 }
 
 class IrDelegatingClassSymbolImpl(delegate: IrClassSymbol) :

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/symbols/IrSymbol.kt

@@ -36,6 +36,9 @@ interface IrSymbol {
     val isBound: Boolean
 
     val signature: IdSignature?
+
+    // Used to store signatures in private symbols for JS IC
+    var privateSignature: IdSignature?
 }
 
 val IrSymbol.isPublicApi: Boolean

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

@@ -30,4 +30,6 @@ class DescriptorlessExternalPackageFragmentSymbol : IrExternalPackageFragmentSym
     override fun bind(owner: IrExternalPackageFragment) {
         _owner = owner
     }
+
+    override var privateSignature: IdSignature? = null
 }

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

@@ -70,6 +70,8 @@ abstract class IrBindableSymbolBase<out D : DeclarationDescriptor, B : IrSymbolO
 
     override val isBound: Boolean
         get() = _owner != null
+
+    override var privateSignature: IdSignature? = null
 }
 
 class IrFileSymbolImpl(descriptor: PackageFragmentDescriptor? = null) :

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

@@ -61,6 +61,8 @@ abstract class IrBindablePublicSymbolBase<out D : DeclarationDescriptor, B : IrS
 
     override val isBound: Boolean
         get() = _owner != null
+
+    override var privateSignature: IdSignature? = null
 }
 
 class IrClassPublicSymbolImpl(sig: IdSignature, descriptor: ClassDescriptor? = null) :

compiler/ir/ir.tree/src/org/jetbrains/kotlin/ir/util/SymbolTable.kt

@@ -488,7 +488,9 @@ open class SymbolTable(
     override fun referenceClassFromLinker(sig: IdSignature): IrClassSymbol =
         classSymbolTable.run {
             if (sig.isPubliclyVisible) referenced(sig, false) { IrClassPublicSymbolImpl(sig) }
-            else IrClassSymbolImpl(signature = sig)
+            else IrClassSymbolImpl().also {
+                it.privateSignature = sig
+            }
         }
 
     val unboundClasses: Set<IrClassSymbol> get() = classSymbolTable.unboundSymbols
@@ -841,7 +843,9 @@ open class SymbolTable(
     override fun referenceSimpleFunctionFromLinker(sig: IdSignature): IrSimpleFunctionSymbol {
         return simpleFunctionSymbolTable.run {
             if (sig.isPubliclyVisible) referenced(sig, false) { IrSimpleFunctionPublicSymbolImpl(sig) }
-            else IrSimpleFunctionSymbolImpl(signature = sig)
+            else IrSimpleFunctionSymbolImpl().also {
+                it.privateSignature = sig
+            }
         }
     }