Move BlockType to WasmInstr.

An alternative would be to move it to Types, but in the Wasm
specification, it is part of the Instructions section, so it
probably makes more sense in `WasmInstr`.

Author: sjrd

wasm/src/main/scala/converters/WasmBinaryWriter.scala

@@ -9,7 +9,7 @@ import java.io.ByteArrayOutputStream
 import wasm.wasm4s._
 import wasm.wasm4s.Names._
 import wasm.wasm4s.Types._
-import wasm.wasm4s.WasmInstr.END
+import wasm.wasm4s.WasmInstr.{BlockType, END}
 
 final class WasmBinaryWriter(module: WasmModule, emitDebugInfo: Boolean) {
   import WasmBinaryWriter._
@@ -448,9 +448,7 @@ final class WasmBinaryWriter(module: WasmModule, emitDebugInfo: Boolean) {
     }
   }
 
-  private def writeBlockType(buf: Buffer, blockType: WasmImmediate.BlockType): Unit = {
-    import WasmImmediate._
-
+  private def writeBlockType(buf: Buffer, blockType: BlockType): Unit = {
     blockType match {
       case BlockType.ValueType(None)        => buf.byte(0x40)
       case BlockType.ValueType(Some(typ))   => writeType(buf, typ)

wasm/src/main/scala/converters/WasmTextWriter.scala

@@ -303,11 +303,11 @@ class WasmTextWriter {
     else v.toString()
   }
 
-  private def writeBlockType(blockType: WasmImmediate.BlockType)(implicit b: WatBuilder): Unit = {
+  private def writeBlockType(blockType: BlockType)(implicit b: WatBuilder): Unit = {
     blockType match {
-      case WasmImmediate.BlockType.FunctionType(name) =>
+      case BlockType.FunctionType(name) =>
         b.appendElement(s"(type ${name.show})")
-      case WasmImmediate.BlockType.ValueType(optTy) =>
+      case BlockType.ValueType(optTy) =>
         for (ty <- optTy)
           b.sameLineList("result", writeType(ty))
     }

wasm/src/main/scala/ir2wasm/HelperFunctions.scala

@@ -37,7 +37,7 @@ object HelperFunctions {
 
   private def genStringLiteral()(implicit ctx: WasmContext): Unit = {
     import WasmTypeName.WasmArrayTypeName
-    import WasmImmediate._
+
     val fctx = WasmFunctionContext(
       WasmFunctionName.stringLiteral,
       List("offset" -> WasmInt32, "size" -> WasmInt32, "stringIndex" -> WasmInt32),
@@ -74,7 +74,6 @@ object HelperFunctions {
 
   /** `createStringFromData: (ref array u16) -> (ref any)` (representing a `string`). */
   private def genCreateStringFromData()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmArrayTypeName
 
     val dataType = WasmRefType(WasmArrayTypeName.i16Array)
@@ -152,7 +151,6 @@ object HelperFunctions {
     *   [[https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/lang/Class.html#getName()]]
     */
   private def genTypeDataName()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName._
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -291,7 +289,6 @@ object HelperFunctions {
     * with the non-null case as a fast-path.
     */
   private def genCreateClassOf()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmStructTypeName
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -412,7 +409,6 @@ object HelperFunctions {
     * performance-sensitive.
     */
   private def genGetClassOf()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmStructTypeName
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -446,7 +442,6 @@ object HelperFunctions {
     * must be be strictly positive.
     */
   private def genArrayTypeData()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName._
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -549,7 +544,6 @@ object HelperFunctions {
     * [[https://lampwww.epfl.ch/~doeraene/sjsir-semantics/#sec-sjsir-createclassdataof]].
     */
   private def genIsInstance()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmStructTypeName
     import WasmFieldIdx.typeData._
 
@@ -719,8 +713,6 @@ object HelperFunctions {
     * This is the underlying func for the `isAssignableFrom()` closure inside class data objects.
     */
   private def genIsAssignableFromExternal()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
-
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
 
     val fctx = WasmFunctionContext(
@@ -753,7 +745,6 @@ object HelperFunctions {
     * Specified by `java.lang.Class.isAssignableFrom(Class)`.
     */
   private def genIsAssignableFrom()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName._
     import WasmFieldIdx.typeData._
 
@@ -913,7 +904,6 @@ object HelperFunctions {
     * This is the underlying func for the `getComponentType()` closure inside class data objects.
     */
   private def genGetComponentType()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmStructTypeName
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -952,7 +942,6 @@ object HelperFunctions {
     * This is the underlying func for the `newArrayOfThisClass()` closure inside class data objects.
     */
   private def genNewArrayOfThisClass()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmStructTypeName
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -1033,7 +1022,6 @@ object HelperFunctions {
     * [[https://www.scala-js.org/doc/semantics.html#getclass]].
     */
   private def genAnyGetClass()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName.WasmStructTypeName
 
     val typeDataType = WasmRefType(WasmStructType.typeData.name)
@@ -1185,7 +1173,6 @@ object HelperFunctions {
     * lengths, lengthIndex - 1)`.
     */
   def genNewArrayObject()(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     import WasmTypeName._
     import WasmFieldIdx.typeData._
 
@@ -1374,7 +1361,6 @@ object HelperFunctions {
     * See https://github.com/tanishiking/scala-wasm/issues/27#issuecomment-2008252049
     */
   def genInstanceTest(clazz: LinkedClass)(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     assert(clazz.kind == ClassKind.Interface)
 
     val fctx = WasmFunctionContext(
@@ -1429,7 +1415,6 @@ object HelperFunctions {
     * called on the class instance.
     */
   def genCloneFunction(clazz: LinkedClass)(implicit ctx: WasmContext): Unit = {
-    import WasmImmediate._
     val info = ctx.getClassInfo(clazz.name.name)
     if (info.ancestors.contains(IRNames.CloneableClass) && !info.isAbstract) {
       val heapType =

wasm/src/main/scala/ir2wasm/WasmBuilder.scala

@@ -6,7 +6,6 @@ import wasm4s.WasmContext._
 import wasm4s.Names._
 import wasm4s.Types._
 import wasm4s.WasmInstr._
-import wasm4s.WasmImmediate._
 import TypeTransformer._
 
 import org.scalajs.ir.{Trees => IRTrees}
@@ -410,7 +409,7 @@ class WasmBuilder {
       // global.get $module_name
       GLOBAL_GET(globalInstanceName), // [rt]
       REF_IS_NULL, // [rt] -> [i32] (bool)
-      IF(WasmImmediate.BlockType.ValueType(None)),
+      IF(BlockType.ValueType()),
       CALL(WasmFunctionName.newDefault(clazz.name.name)),
       GLOBAL_SET(globalInstanceName),
       GLOBAL_GET(globalInstanceName),

wasm/src/main/scala/ir2wasm/WasmExpressionBuilder.scala

@@ -13,7 +13,6 @@ import wasm4s._
 import wasm4s.Names._
 import wasm4s.Names.WasmTypeName._
 import wasm4s.WasmInstr._
-import wasm4s.WasmImmediate._
 import org.scalajs.ir.Types.ClassType
 import org.scalajs.ir.ClassKind
 import org.scalajs.ir.Position

wasm/src/main/scala/wasm4s/Defaults.scala

@@ -1,7 +1,6 @@
 package wasm4s
 
 import wasm.wasm4s.Types._
-import wasm.wasm4s.WasmImmediate._
 import wasm.wasm4s.WasmInstr
 import wasm.wasm4s.WasmInstr._
 

wasm/src/main/scala/wasm4s/Instructions.scala

@@ -8,8 +8,6 @@ import Names.WasmTypeName._
 sealed abstract class WasmInstr(val mnemonic: String, val opcode: Int)
 
 object WasmInstr {
-  import WasmImmediate._
-
   // Semantic categories of instructions
 
   /** A stack-polymorphic instruction. */
@@ -365,9 +363,8 @@ object WasmInstr {
     case class CatchAll(l: WasmLabelName) extends CatchClause("catch_all", 0x02, None, l)
     case class CatchAllRef(l: WasmLabelName) extends CatchClause("catch_all_ref", 0x03, None, l)
   }
-}
 
-object WasmImmediate {
+  // Block types
 
   /** A structured instruction can consume input and produce output on the operand stack according
     * to its annotated block type. It is given either as a type index that refers to a suitable
@@ -376,10 +373,10 @@ object WasmImmediate {
     * @see
     *   https://webassembly.github.io/spec/core/syntax/instructions.html#control-instructions
     */
-  abstract sealed trait BlockType
+  sealed abstract class BlockType
   object BlockType {
     case class FunctionType(ty: WasmFunctionTypeName) extends BlockType
-    case class ValueType private (ty: Option[WasmType]) extends BlockType
+    case class ValueType(ty: Option[WasmType]) extends BlockType
     object ValueType {
       def apply(ty: WasmType): ValueType = ValueType(Some(ty))
       def apply(): ValueType = ValueType(None)

wasm/src/main/scala/wasm4s/WasmFunctionContext.scala

@@ -8,7 +8,6 @@ import org.scalajs.ir.{Trees => IRTrees}
 
 import wasm.wasm4s.Names._
 import wasm.wasm4s.Types.WasmType
-import wasm.wasm4s.WasmImmediate.BlockType
 import wasm.wasm4s.WasmInstr._
 
 import wasm.ir2wasm.TypeTransformer