[Wasm] Move non-recursive function types out of rec group

This fixes linking with other wasm modules with non-rec types

wasm/wasm.ir/src/org/jetbrains/kotlin/wasm/ir/Declarations.kt

@@ -10,9 +10,7 @@ import org.jetbrains.kotlin.wasm.ir.source.location.SourceLocation
 
 class WasmModule(
     val functionTypes: List<WasmFunctionType> = emptyList(),
-    val gcTypes: List<WasmTypeDeclaration> = emptyList(),
-    val gcTypesInRecursiveGroup: Boolean,
-
+    val recGroupTypes: List<WasmTypeDeclaration> = emptyList(),
     val importsInOrder: List<WasmNamedModuleField> = emptyList(),
     val importedFunctions: List<WasmFunction.Imported> = emptyList(),
     val importedMemories: List<WasmMemory> = emptyList(),

wasm/wasm.ir/src/org/jetbrains/kotlin/wasm/ir/Types.kt

@@ -77,3 +77,15 @@ fun WasmType.getHeapType(): WasmHeapType =
         is WasmExternRef -> WasmHeapType.Simple.Extern
         else -> error("Unknown heap type for type $this")
     }
+
+fun WasmFunctionType.referencesTypeDeclarations(): Boolean =
+    parameterTypes.any { it.referencesTypeDeclaration() } or resultTypes.any { it.referencesTypeDeclaration() }
+
+fun WasmType.referencesTypeDeclaration(): Boolean {
+    val heapType = when (this) {
+        is WasmRefNullType -> getHeapType()
+        is WasmRefType -> getHeapType()
+        else -> return false
+    }
+    return heapType is WasmHeapType.Type
+}

wasm/wasm.ir/src/org/jetbrains/kotlin/wasm/ir/Utils.kt

@@ -16,7 +16,7 @@ fun WasmModule.calculateIds() {
     }
 
     functionTypes.calculateIds()
-    gcTypes.calculateIds(startIndex = functionTypes.size)
+    recGroupTypes.calculateIds(startIndex = functionTypes.size)
     importedFunctions.calculateIds()
     importedMemories.calculateIds()
     importedTables.calculateIds()

wasm/wasm.ir/src/org/jetbrains/kotlin/wasm/ir/convertors/WasmBinaryToIR.kt

@@ -329,8 +329,7 @@ class WasmBinaryToIR(val b: MyByteReader) {
 
         return WasmModule(
             functionTypes = functionTypes,
-            gcTypes = gcTypes,
-            gcTypesInRecursiveGroup = false,
+            recGroupTypes = gcTypes,
             importsInOrder = importsInOrder,
             importedFunctions = importedFunctions,
             importedMemories = importedMemories,

wasm/wasm.ir/src/org/jetbrains/kotlin/wasm/ir/convertors/WasmIrToBinary.kt

@@ -35,17 +35,18 @@ class WasmIrToBinary(
         with(module) {
             // type section
             appendSection(1u) {
-                if (module.gcTypesInRecursiveGroup) {
-                    appendVectorSize(1)
-                    b.writeByte(0x4f)
-                }
-                appendVectorSize(functionTypes.size + gcTypes.size)
+                val numRecGroups = if (recGroupTypes.isEmpty()) 0 else 1
+                appendVectorSize(functionTypes.size + numRecGroups)
                 functionTypes.forEach { appendFunctionTypeDeclaration(it) }
-                gcTypes.forEach {
-                    when (it) {
-                        is WasmStructDeclaration -> appendStructTypeDeclaration(it)
-                        is WasmArrayDeclaration -> appendArrayTypeDeclaration(it)
-                        is WasmFunctionType -> error("Function type in GC types")
+                if (!recGroupTypes.isEmpty()) {
+                    b.writeByte(0x4f)
+                    appendVectorSize(recGroupTypes.size)
+                    recGroupTypes.forEach {
+                        when (it) {
+                            is WasmStructDeclaration -> appendStructTypeDeclaration(it)
+                            is WasmArrayDeclaration -> appendArrayTypeDeclaration(it)
+                            is WasmFunctionType -> appendFunctionTypeDeclaration(it)
+                        }
                     }
                 }
             }
@@ -172,8 +173,8 @@ class WasmIrToBinary(
             // https://github.com/WebAssembly/extended-name-section/blob/main/document/core/appendix/custom.rst
 
             appendSection(4u) {
-                appendVectorSize(module.gcTypes.size)
-                module.gcTypes.forEach {
+                appendVectorSize(module.recGroupTypes.size)
+                module.recGroupTypes.forEach {
                     appendModuleFieldReference(it)
                     b.writeString(it.name)
                 }
@@ -190,7 +191,7 @@ class WasmIrToBinary(
             // Experimental fields name section
             // https://github.com/WebAssembly/gc/issues/193
             appendSection(10u) {
-                val structDeclarations = module.gcTypes.filterIsInstance<WasmStructDeclaration>()
+                val structDeclarations = module.recGroupTypes.filterIsInstance<WasmStructDeclaration>()
                 appendVectorSize(structDeclarations.size)
                 structDeclarations.forEach {
                     appendModuleFieldReference(it)

wasm/wasm.ir/src/org/jetbrains/kotlin/wasm/ir/convertors/WasmIrToText.kt

@@ -228,13 +228,14 @@ class WasmIrToText : SExpressionBuilder() {
         with(module) {
             newLineList("module") {
                 functionTypes.forEach { appendFunctionTypeDeclaration(it) }
-                gcTypes.forEach {
+                recGroupTypes.forEach {
                     when (it) {
                         is WasmStructDeclaration ->
                             appendStructTypeDeclaration(it)
                         is WasmArrayDeclaration ->
                             appendArrayTypeDeclaration(it)
-                        else -> error("Unexpected GC type: $it")
+                        is WasmFunctionType ->
+                            appendFunctionTypeDeclaration(it)
                     }
                 }
                 importsInOrder.forEach {