[IR] Support stable ordering in Kotlin-like IR dump

This is needed for signature tests to work with the same golden data
on both K1 and K2, since sometimes K1 and K2 produce IR with different
order of declarations and supertypes.

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

@@ -48,6 +48,37 @@ private fun IrFile.shouldSkipDump(): Boolean {
     return entry.lineStartOffsetsAreEmpty
 }
 
+/**
+ * Sorts the declarations in the list using the result of [IrDeclaration.render] as the sorting key.
+ *
+ * The exception is properties with backing fields and [IrAnonymousInitializer]s: their relative order is preserved.
+ */
+internal fun List<IrDeclaration>.stableOrdered(): List<IrDeclaration> {
+    val strictOrder = hashMapOf<IrDeclaration, Int>()
+
+    var idx = 0
+
+    forEach {
+        if (it is IrProperty && it.backingField != null && !it.isConst) {
+            strictOrder[it] = idx++
+        }
+        if (it is IrAnonymousInitializer) {
+            strictOrder[it] = idx++
+        }
+    }
+
+    return sortedWith { a, b ->
+        val strictA = strictOrder[a] ?: Int.MAX_VALUE
+        val strictB = strictOrder[b] ?: Int.MAX_VALUE
+
+        if (strictA == strictB) {
+            val rA = a.render()
+            val rB = b.render()
+            rA.compareTo(rB)
+        } else strictA - strictB
+    }
+}
+
 class DumpIrTreeVisitor(
     out: Appendable,
     normalizeNames: Boolean = false,
@@ -58,33 +89,7 @@ class DumpIrTreeVisitor(
     private val elementRenderer = RenderIrElementVisitor(normalizeNames, !stableOrder)
     private fun IrType.render() = elementRenderer.renderType(this)
 
-    private fun List<IrDeclaration>.ordered(): List<IrDeclaration> {
-        if (!stableOrder) return this
-
-        val strictOrder = mutableMapOf<IrDeclaration, Int>()
-
-        var idx = 0
-
-        forEach {
-            if (it is IrProperty && it.backingField != null && !it.isConst) {
-                strictOrder[it] = idx++
-            }
-            if (it is IrAnonymousInitializer) {
-                strictOrder[it] = idx++
-            }
-        }
-
-        return sortedWith { a, b ->
-            val strictA = strictOrder[a] ?: Int.MAX_VALUE
-            val strictB = strictOrder[b] ?: Int.MAX_VALUE
-
-            if (strictA == strictB) {
-                val rA = a.render()
-                val rB = b.render()
-                rA.compareTo(rB)
-            } else strictA - strictB
-        }
-    }
+    private fun List<IrDeclaration>.ordered(): List<IrDeclaration> = if (stableOrder) stableOrdered() else this
 
     override fun visitElement(element: IrElement, data: String) {
         element.dumpLabeledElementWith(data) {

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

@@ -66,6 +66,7 @@ class KotlinLikeDumpOptions(
     val printFakeOverridesStrategy: FakeOverridesStrategy = FakeOverridesStrategy.ALL,
     val bodyPrintingStrategy: BodyPrintingStrategy = BodyPrintingStrategy.PRINT_BODIES,
     val printElseAsTrue: Boolean = false,
+    val stableOrder: Boolean = false,
     /*
     TODO add more options:
      always print visibility?
@@ -166,6 +167,22 @@ private class KotlinLikeDumper(val p: Printer, val options: KotlinLikeDumpOption
         typeArg.printTypeArgumentWithNoIndent()
     }
 
+    @JvmName("orderedDeclarations") // Prevent JVM signature clash
+    private fun List<IrDeclaration>.ordered() = if (options.stableOrder) stableOrdered() else this
+
+    @JvmName("orderedTypes") // Prevent JVM signature clash
+    private fun List<IrType>.ordered(): List<IrType> {
+        if (!options.stableOrder) return this
+
+        fun isNonInterfaceType(type: IrType) = type.classifierOrNull?.let {
+            it !is IrClassSymbol || !it.owner.isInterface
+        } ?: true
+
+        val (classTypes, interfaceTypes) = partition(::isNonInterfaceType)
+
+        return classTypes.sortedBy(IrType::render) + interfaceTypes.sortedBy(IrType::render)
+    }
+
     override fun visitElement(element: IrElement, data: IrDeclaration?) {
         val e = "/* ERROR: unsupported element type: " + element.javaClass.simpleName + " */"
         if (element is IrExpression) {
@@ -195,7 +212,7 @@ private class KotlinLikeDumper(val p: Printer, val options: KotlinLikeDumpOption
         }
         if (!p.isEmpty) p.printlnWithNoIndent()
 
-        declaration.declarations.forEach { it.accept(this, null) }
+        declaration.declarations.ordered().forEach { it.accept(this, null) }
 
         if (options.printRegionsPerFile) p.println("//endregion")
     }
@@ -240,7 +257,7 @@ private class KotlinLikeDumper(val p: Printer, val options: KotlinLikeDumpOption
         // TODO no test
         if (declaration.superTypes.isNotEmpty()) {
             var first = true
-            for (type in declaration.superTypes) {
+            for (type in declaration.superTypes.ordered()) {
                 if (type.isAny()) continue
 
                 if (!first) {
@@ -260,7 +277,7 @@ private class KotlinLikeDumper(val p: Printer, val options: KotlinLikeDumpOption
         p.printlnWithNoIndent(" {")
         p.pushIndent()
 
-        declaration.declarations.forEach { it.accept(this, declaration) }
+        declaration.declarations.ordered().forEach { it.accept(this, declaration) }
 
         p.popIndent()
         p.println("}")
@@ -431,7 +448,7 @@ private class KotlinLikeDumper(val p: Printer, val options: KotlinLikeDumpOption
 
     private fun IrTypeParameter.printWhereClauseTypesWithNoIndent(first: Boolean): Boolean {
         var myFirst = first
-        superTypes.forEach { type ->
+        superTypes.ordered().forEach { type ->
             if (!myFirst) {
                 p.printWithNoIndent(", ")
             } else {