[Wasm] Improve interface method dispatch

- Use typed Wasm tables for each interface method to avoid runtime
  function type check

- Use linear search by implemented interface rather than by individual
  virtual function signature

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

@@ -76,7 +76,7 @@ class WasmData(
 ) : WasmNamedModuleField()
 
 class WasmTable(
-    val limits: WasmLimits = WasmLimits(1u, null),
+    var limits: WasmLimits = WasmLimits(1u, null),
     val elementType: WasmType,
     val importPair: WasmImportPair? = null
 ) : WasmNamedModuleField() {

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

@@ -73,7 +73,9 @@ sealed class WasmImmediate {
     }
 
     class DataIdx(val value: Int) : WasmImmediate()
-    class TableIdx(val value: Int) : WasmImmediate()
+    class TableIdx(val value: WasmSymbolReadOnly<Int>) : WasmImmediate() {
+        constructor(value: Int) : this(WasmSymbol(value))
+    }
 
     class LabelIdx(val value: Int) : WasmImmediate()
     class LabelIdxVector(val value: List<Int>) : WasmImmediate()

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

@@ -33,3 +33,10 @@ class WasmSymbol<out T : Any>(owner: T? = null) : WasmSymbolReadOnly<T> {
     override fun toString(): String =
         _owner?.toString() ?: "UNBOUND-WASM-SYMBOL"
 }
+
+class WasmSymbolIntWrapper(val symbol: WasmSymbol<WasmNamedModuleField>) : WasmSymbolReadOnly<Int> {
+    override val owner: Int
+        get() = symbol.owner.id!!
+
+    override fun toString() = owner.toString()
+}

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

@@ -82,11 +82,14 @@ abstract class WasmExpressionBuilder {
         buildInstr(WasmOp.CALL, WasmImmediate.FuncIdx(symbol))
     }
 
-    fun buildCallIndirect(symbol: WasmSymbol<WasmFunctionType>) {
+    fun buildCallIndirect(
+        symbol: WasmSymbol<WasmFunctionType>,
+        tableIdx: WasmSymbolReadOnly<Int> = WasmSymbol(0),
+    ) {
         buildInstr(
             WasmOp.CALL_INDIRECT,
             WasmImmediate.TypeIdx(symbol),
-            WasmImmediate.TableIdx(0)
+            WasmImmediate.TableIdx(tableIdx)
         )
     }
 

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

@@ -23,3 +23,9 @@ class WasmIrExpressionBuilder(
     override val lastInstr: WasmOp?
         get() = expression.lastOrNull()?.operator
 }
+
+inline fun buildWasmExpression(body: WasmExpressionBuilder.() -> Unit): MutableList<WasmInstr> {
+    val res = mutableListOf<WasmInstr>()
+    WasmIrExpressionBuilder(res).body()
+    return res
+}

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

@@ -138,7 +138,7 @@ class WasmIrToBinary(outputStream: OutputStream, val module: WasmModule) {
             is WasmImmediate.TypeIdx -> appendModuleFieldReference(x.value.owner)
             is WasmImmediate.MemoryIdx -> appendModuleFieldReference(x.value.owner)
             is WasmImmediate.DataIdx -> b.writeVarUInt32(x.value)
-            is WasmImmediate.TableIdx -> b.writeVarUInt32(x.value)
+            is WasmImmediate.TableIdx -> b.writeVarUInt32(x.value.owner)
             is WasmImmediate.LabelIdx -> b.writeVarUInt32(x.value)
             is WasmImmediate.LabelIdxVector -> {
                 b.writeVarUInt32(x.value.size)
@@ -243,7 +243,7 @@ class WasmIrToBinary(outputStream: OutputStream, val module: WasmModule) {
             b.writeByte(1)
         }
 
-        b.writeVarInt7(table.elementType.code)
+        appendType(table.elementType)
         appendLimits(table.limits)
     }
 
@@ -286,7 +286,7 @@ class WasmIrToBinary(outputStream: OutputStream, val module: WasmModule) {
     }
 
     private fun appendElement(element: WasmElement) {
-        val isFuncIndices = element.values.all { it is WasmTable.Value.Function }
+        val isFuncIndices = element.values.all { it is WasmTable.Value.Function } && element.type == WasmFuncRef
 
         val funcIndices = if (isFuncIndices) {
             element.values.map { (it as WasmTable.Value.Function).function.owner.id!! }