Check specialized method body

Author: liufengyun

compiler/src/dotty/tools/dotc/transform/SpecializeFunctions.scala

@@ -25,16 +25,16 @@ class SpecializeFunctions extends MiniPhase with InfoTransformer {
   /** Transforms the type to include decls for specialized applys  */
   override def transformInfo(tp: Type, sym: Symbol)(using Context) = tp match {
     case tp: ClassInfo =>
-      val apply = tp.decls.lookup(nme.apply)
-      if (!apply.exists) return tp
-
       val newApplys = new mutable.ListBuffer[Symbol]
 
       var arity = 0
       while (arity < 3) {
         val func = defn.FunctionClass(arity)
-        if (tp.derivesFrom(func)) {
-          val paramTypes = tp.cls.typeRef.baseType(func).argInfos
+        if (sym.derivesFrom(func)) {
+          val baseType = tp.cls.typeRef.baseType(func)
+          val apply = baseType.member(nme.apply)
+
+          val paramTypes = baseType.argInfos
           val argTypes = paramTypes.init
           val retType  = paramTypes.last
 
@@ -87,6 +87,7 @@ class SpecializeFunctions extends MiniPhase with InfoTransformer {
 
         val specName = nme.apply.specializedFunction(retType, paramTypes)
         val specializedApply = cls.info.decls.lookup(specName)
+
         if (specializedApply.exists) {
           val specializedDecl =
             DefDef(specializedApply.asTerm, vparamss => {

compiler/test/dotty/tools/backend/jvm/DottyBytecodeTest.scala

@@ -259,6 +259,17 @@ trait DottyBytecodeTest {
     (ins, boxed)
   }
 
+  protected def hasInvokeStatic(method: MethodNode): Boolean = {
+    val ins = instructionsFromMethod(method)
+    ins.exists {
+      case Invoke(op, owner, name, desc, itf) =>
+        println("owner = " + owner)
+        println("name = " + name)
+        op == 184
+      case _ => false
+    }
+  }
+
 }
 object DottyBytecodeTest {
   extension [T](l: List[T]) def stringLines = l.mkString("\n")

compiler/test/dotty/tools/dotc/transform/SpecializeFunctionsTests.scala

@@ -50,7 +50,9 @@ class SpecializeFunctionsTests extends DottyBytecodeTest {
     checkBCode(source) { dir =>
       val apps =
         findClass("Func2", dir).methods.asScala.collect {
-          case m if m.name == "apply$mcIII$sp" => m
+          case m if m.name == "apply$mcIII$sp" =>
+            assert(!hasInvokeStatic(m)) // should not call super specialized method
+            m
           case m if m.name == "apply" => m
         }
         .map(_.name)