Merge pull request scala#4842 from adriaanm/fields-prep

Set the scene for phase 1 of the new trait encoding.

Author: adriaanm

src/compiler/scala/tools/nsc/Global.scala

@@ -384,15 +384,6 @@ class Global(var currentSettings: Settings, var reporter: Reporter)
 
     def apply(unit: CompilationUnit): Unit
 
-    private val isErased = prev.name == "erasure" || prev.erasedTypes
-    override def erasedTypes: Boolean = isErased
-    private val isFlat = prev.name == "flatten" || prev.flatClasses
-    override def flatClasses: Boolean = isFlat
-    private val isSpecialized = prev.name == "specialize" || prev.specialized
-    override def specialized: Boolean = isSpecialized
-    private val isRefChecked = prev.name == "refchecks" || prev.refChecked
-    override def refChecked: Boolean = isRefChecked
-
     /** Is current phase cancelled on this unit? */
     def cancelled(unit: CompilationUnit) = {
       // run the typer only if in `createJavadoc` mode

src/compiler/scala/tools/nsc/backend/jvm/AsmUtils.scala

@@ -8,8 +8,9 @@ package scala.tools.nsc.backend.jvm
 import scala.tools.asm.tree.{InsnList, AbstractInsnNode, ClassNode, MethodNode}
 import java.io.{StringWriter, PrintWriter}
 import scala.tools.asm.util.{CheckClassAdapter, TraceClassVisitor, TraceMethodVisitor, Textifier}
-import scala.tools.asm.{ClassWriter, Attribute, ClassReader}
+import scala.tools.asm.{ClassReader, ClassWriter, Attribute}
 import scala.collection.convert.decorateAsScala._
+import scala.collection.convert.decorateAsJava._
 import scala.tools.nsc.backend.jvm.analysis.InitialProducer
 import scala.tools.nsc.backend.jvm.opt.InlineInfoAttributePrototype
 
@@ -55,11 +56,30 @@ object AsmUtils {
     node
   }
 
-  def readClass(filename: String): ClassNode = {
-    val f = new java.io.RandomAccessFile(filename, "r")
-    val b = new Array[Byte](f.length.toInt)
-    f.read(b)
-    readClass(b)
+  def readClass(filename: String): ClassNode = readClass(classBytes(filename))
+
+  def classBytes(file: String): Array[Byte] = {
+    val f = new java.io.RandomAccessFile(file, "r")
+    val bytes = new Array[Byte](f.length.toInt)
+    f.read(bytes)
+    bytes
+  }
+
+  def textifyClassStably(bytes: Array[Byte]): Unit = {
+    val node = new ClassNode()
+    new ClassReader(bytes).accept(node, ClassReader.SKIP_DEBUG | ClassReader.SKIP_FRAMES)
+
+    node.fields  = node.fields.asScala.sortBy(_.name).asJava
+    node.methods = node.methods.asScala.sortBy(_.name).asJava
+    node.visibleAnnotations = null
+    node.attrs = null
+    node.invisibleAnnotations = null
+
+    println(textify(node))
+  }
+
+  def main(args: Array[String]): Unit = {
+    textifyClassStably(classBytes(args.head))
   }
 
   /**

src/compiler/scala/tools/nsc/backend/jvm/BCodeHelpers.scala

@@ -1052,7 +1052,7 @@ abstract class BCodeHelpers extends BCodeIdiomatic with BytecodeWriters {
 
       for (m <- moduleClass.info.membersBasedOnFlags(BCodeHelpers.ExcludedForwarderFlags, symtab.Flags.METHOD)) {
         if (m.isType || m.isDeferred || (m.owner eq definitions.ObjectClass) || m.isConstructor)
-          debuglog(s"No forwarder for '$m' from $jclassName to '$moduleClass'")
+          debuglog(s"No forwarder for '$m' from $jclassName to '$moduleClass': ${m.isType} || ${m.isDeferred} || ${m.owner eq definitions.ObjectClass} || ${m.isConstructor}")
         else if (conflictingNames(m.name))
           log(s"No forwarder for $m due to conflict with ${linkedClass.info.member(m.name)}")
         else if (m.hasAccessBoundary)

src/compiler/scala/tools/nsc/transform/AddInterfaces.scala

@@ -242,20 +242,18 @@ abstract class AddInterfaces extends InfoTransform { self: Erasure =>
     }
   }
 
-  private def createMemberDef(tree: Tree, isForInterface: Boolean)(create: Tree => Tree) = {
-    val isInterfaceTree = tree.isDef && isInterfaceMember(tree.symbol)
-    if (isInterfaceTree && needsImplMethod(tree.symbol))
-      create(tree)
-    else if (isInterfaceTree == isForInterface)
-      tree
-    else
-      EmptyTree
-  }
-  private def implMemberDef(tree: Tree): Tree  = createMemberDef(tree, false)(implMethodDef)
-  private def ifaceMemberDef(tree: Tree): Tree = createMemberDef(tree, true)(t => DefDef(t.symbol, EmptyTree))
+  private def isInterfaceTree(tree: Tree) = tree.isDef && isInterfaceMember(tree.symbol)
+
+  private def deriveMemberForImplClass(tree: Tree): Tree  =
+    if (isInterfaceTree(tree)) if (needsImplMethod(tree.symbol)) implMethodDef(tree)            else EmptyTree
+    else tree
+
+  private def deriveMemberForInterface(tree: Tree): Tree =
+    if (isInterfaceTree(tree)) if (needsImplMethod(tree.symbol)) DefDef(tree.symbol, EmptyTree) else tree
+    else EmptyTree
 
   private def ifaceTemplate(templ: Template): Template =
-    treeCopy.Template(templ, templ.parents, noSelfType, templ.body map ifaceMemberDef)
+    treeCopy.Template(templ, templ.parents, noSelfType, templ.body map deriveMemberForInterface)
 
   /** Transforms the member tree containing the implementation
    *  into a member of the impl class.
@@ -286,7 +284,7 @@ abstract class AddInterfaces extends InfoTransform { self: Erasure =>
 
   private def implTemplate(clazz: Symbol, templ: Template): Template = atPos(templ.pos) {
     val templ1 = (
-      Template(templ.parents, noSelfType, addMixinConstructorDef(clazz, templ.body map implMemberDef))
+      Template(templ.parents, noSelfType, addMixinConstructorDef(clazz, templ.body map deriveMemberForImplClass))
         setSymbol clazz.newLocalDummy(templ.pos)
     )
     templ1.changeOwner(templ.symbol.owner -> clazz, templ.symbol -> templ1.symbol)

src/compiler/scala/tools/nsc/transform/CleanUp.scala

@@ -49,7 +49,9 @@ abstract class CleanUp extends Statics with Transform with ast.TreeDSL {
       clearStatics()
       val newBody = transformTrees(body)
       val templ   = deriveTemplate(tree)(_ => transformTrees(newStaticMembers.toList) ::: newBody)
-      try addStaticInits(templ, newStaticInits, localTyper) // postprocess to include static ctors
+      try
+        if (newStaticInits.isEmpty) templ
+        else deriveTemplate(templ)(body => staticConstructor(body, localTyper, templ.pos)(newStaticInits.toList) :: body)
       finally clearStatics()
     }
     private def mkTerm(prefix: String): TermName = unit.freshTermName(prefix)