started adapting backend to dotty symbols, denotations, etc

src/dotty/tools/dotc/Driver.scala

@@ -29,14 +29,11 @@ abstract class Driver extends DotClass {
     try {
       doCompile(newCompiler(), fileNames)
     } catch {
+      case ex: FatalError  =>
+        ctx.error(ex.getMessage) // signals that we should fail compilation.
+        ctx.typerState.reporter
       case ex: Throwable =>
-        ex match {
-          case ex: FatalError  =>
-            ctx.error(ex.getMessage) // signals that we should fail compilation.
-            ctx.typerState.reporter
-          case _ =>
-            throw ex // unexpected error, tell the outside world.
-        }
+        throw ex // unexpected error, tell the outside world.
     }
   }
 

src/dotty/tools/dotc/ast/Trees.scala

@@ -260,7 +260,7 @@ object Trees {
       case _ => NoType
     }
 
-    /** The denotation referred tno by this tree.
+    /** The denotation referred to by this tree.
      *  Defined for `DenotingTree`s and `ProxyTree`s, NoDenotation for other
      *  kinds of trees
      */

src/dotty/tools/dotc/backend/jvm/BCodeBodyBuilder.scala

@@ -18,7 +18,9 @@ import dotc.ast.Trees._
 import core.Types.Type
 import core.StdNames
 import core.Symbols.{Symbol, NoSymbol}
+import core.SymDenotations._
 import core.Constants.Constant
+import config.Printers.bcknd
 
 /*
  *
@@ -33,7 +35,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder {
   /*
    * Functionality to build the body of ASM MethodNode, except for `synchronized` and `try` expressions.
    */
-  abstract class PlainBodyBuilder(cunit:   CompilationUnit,
+  abstract class PlainBodyBuilder(cunit: CompilationUnit,
                                   implicit val ctx: dotc.core.Contexts.Context) extends PlainSkelBuilder(cunit) {
 
     import icodes.TestOp
@@ -44,8 +46,8 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder {
      *  it is the host class; otherwise the symbol's owner.
      */
     def findHostClass(selector: Type, sym: Symbol) = selector member sym.name match {
-      case NoSymbol   => debuglog(s"Rejecting $selector as host class for $sym") ; sym.owner
-      case _          => selector.typeSymbol
+      case NoDenotation => bcknd.println(s"Rejecting $selector as host class for $sym") ; sym.owner
+      case _            => selector.typeSymbol
     }
 
     /* ---------------- helper utils for generating methods and code ---------------- */

src/dotty/tools/dotc/backend/jvm/BCodeHelpers.scala

@@ -10,13 +10,16 @@ package backend.jvm
 import scala.tools.asm
 import scala.annotation.switch
 import scala.collection.{ immutable, mutable }
-import scala.tools.nsc.io.AbstractFile
+import dotty.tools.io.AbstractFile
 
 import dotc.ast.Trees._
 
 import dotc.core.StdNames
 import dotc.core.Types.Type
 import dotc.core.Symbols.{Symbol, NoSymbol}
+import dotc.core.SymDenotations._
+import dotc.core.Flags
+import dotc.core.StdNames.{nme, tpnme}
 
 /*
  *  Traits encapsulating functionality to convert Scala AST Trees into ASM ClassNodes.
@@ -435,37 +438,36 @@ abstract class BCodeHelpers extends BCodeTypes with BytecodeWriters {
      *  Tracks (if needed) the inner class given by `t`.
      *
      * must-single-thread
+     * 
+     * TODO(lry): check if `ctx` should be a paramter of the class instead.
      */
-    final def toTypeKind(t: Type): BType = {
+    final def toTypeKind(t: Type)(implicit ctx: dotc.core.Contexts.Context): BType = {
 
       /* Interfaces have to be handled delicately to avoid introducing spurious errors,
        *  but if we treat them all as AnyRef we lose too much information.
        */
-      def newReference(sym0: Symbol): BType = {
-        assert(!primitiveTypeMap.contains(sym0), "Use primitiveTypeMap instead.")
-        assert(sym0 != definitions.ArrayClass,   "Use arrayOf() instead.")
-
-        if (sym0 == definitions.NullClass)    return RT_NULL;
-        if (sym0 == definitions.NothingClass) return RT_NOTHING;
-
-        val sym = (
-          if (!sym0.isPackageClass) sym0
-          else sym0.info.member(nme.PACKAGE) match {
-            case NoSymbol => abort(s"SI-5604: Cannot use package as value: ${sym0.fullName}")
-            case s        => abort(s"SI-5604: found package class where package object expected: $s")
+      def newReference(sym: Symbol): BType = {
+        assert(!primitiveTypeMap.contains(sym),   "Use primitiveTypeMap instead.")
+        assert(sym != ctx.definitions.ArrayClass, "Use arrayOf() instead.")
+
+        if (sym == ctx.definitions.NullClass)    return RT_NULL;
+        if (sym == ctx.definitions.NothingClass) return RT_NOTHING;
+
+        if (sym is Flags.PackageClass) {
+          sym.info.member(nme.PACKAGE) match {
+            case NoDenotation => throw new FatalError(s"SI-5604: Cannot use package as value: ${sym.fullName}")
+            case s            => throw new FatalError(s"SI-5604: found package class where package object expected: $s")
           }
-        )
+        }
 
-        // Can't call .toInterface (at this phase) or we trip an assertion.
-        // See PackratParser#grow for a method which fails with an apparent mismatch
-        // between "object PackratParsers$class" and "trait PackratParsers"
-        if (sym.isImplClass) {
-          // pos/spec-List.scala is the sole failure if we don't check for NoSymbol
-          val traitSym = sym.owner.info.decl(tpnme.interfaceName(sym.name))
-          if (traitSym != NoSymbol) {
+        if (sym is Flags.ImplClass) {
+          val traitDenot = sym.owner.info.decl(tpnme.interfaceName(sym.name))
+          // scalac legacy: the `if` check below should not be needed.
+          // pos/spec-List.scala is the sole failure if we don't check for NoDenotation
+          // if (traitDenot != NoDenotation) {
             // this tracks the inner class in innerClassBufferASM, if needed.
-            return asmClassType(traitSym)
-          }
+            return asmClassType(traitDenot.symbol)
+          // }
         }
 
         assert(hasInternalName(sym), s"Invoked for a symbol lacking JVM internal name: ${sym.fullName}")

src/dotty/tools/dotc/backend/jvm/BCodeTypes.scala

@@ -14,8 +14,10 @@ import dotc.ast.Trees.Tree
 import dotc.core.Types.Type
 import dotc.core.StdNames
 import dotc.core.Symbols.{Symbol, NoSymbol}
+import dotc.core.SymDenotations._
+import dotc.core.Flags
 
-import StdNames.nme
+import StdNames.{nme, tpnme}
 
 /*
  *  Utilities to mediate between types as represented in Scala ASTs and ASM trees.
@@ -378,13 +380,15 @@ abstract class BCodeTypes extends BCodeIdiomatic {
    * On the other hand, this method does record the inner-class status of the argument, via `buildExemplar()`.
    *
    * must-single-thread
+   * 
+   * TODO(lry) check if ctx should be a class parameter
    */
-  final def exemplar(csym0: Symbol): Tracked = {
+  final def exemplar(csym0: Symbol)(implicit ctx: dotc.core.Contexts.Context): Tracked = {
     assert(csym0 != NoSymbol, "NoSymbol can't be tracked")
 
     val csym = {
-      if (csym0.isJavaDefined && csym0.isModuleClass) csym0.linkedClassOfClass
-      else if (csym0.isModule) csym0.moduleClass
+      if ((csym0 is Flags.JavaDefined) && (csym0 is Flags.ModuleClass)) csym0.linkedClass
+      else if (csym0 is Flags.ModuleVal) csym0.moduleClass
       else csym0 // we track only module-classes and plain-classes
     }
 

src/dotty/tools/dotc/backend/jvm/GenBCode.scala

@@ -50,7 +50,7 @@ import dotc.core.Symbols.{Symbol, NoSymbol}
 object GenBCode extends BCodeSyncAndTry {
 
   final class PlainClassBuilder(cunit: CompilationUnit,
-                                ctx:   dotc.core.Contexts.Context) extends SyncAndTryBuilder(cunit)
+                                ctx:   dotc.core.Contexts.Context) extends SyncAndTryBuilder(cunit, ctx)
 
   class BCodePhase extends dotc.core.Phases.Phase {
 
@@ -64,7 +64,7 @@ object GenBCode extends BCodeSyncAndTry {
 
     /* ---------------- q1 ---------------- */
 
-    case class Item1(arrivalPos: Int, cd: ast.Trees.TypeDef, cunit: CompilationUnit) {
+    case class Item1(arrivalPos: Int, cd: ast.tpd.TypeDef, cunit: CompilationUnit) {
       def isPoison = { arrivalPos == Int.MaxValue }
     }
     private val poison1 = Item1(Int.MaxValue, null, null)

src/dotty/tools/dotc/config/Printers.scala

@@ -10,16 +10,17 @@ object Printers {
     override def println(msg: => String): Unit = ()
   }
 
-  val default: Printer = new Printer
-  val core: Printer = noPrinter
-  val typr: Printer = noPrinter
-  val constr: Printer = noPrinter
-  val overload: Printer = noPrinter
-  val implicits: Printer = noPrinter
+  val default: Printer           = new Printer
+  val core: Printer              = noPrinter
+  val typr: Printer              = noPrinter
+  val constr: Printer            = noPrinter
+  val overload: Printer          = noPrinter
+  val implicits: Printer         = noPrinter
   val implicitsDetailed: Printer = noPrinter
-  val subtyping: Printer = noPrinter
-  val unapp: Printer = noPrinter
-  val completions = noPrinter
-  val gadts = noPrinter
+  val subtyping: Printer         = noPrinter
+  val unapp: Printer             = noPrinter
+  val completions: Printer       = noPrinter
+  val gadts: Printer             = noPrinter
+  val bcknd: Printer             = noPrinter
 
 }

src/dotty/tools/dotc/core/Flags.scala

@@ -25,7 +25,9 @@ object Flags {
         FlagSet(tbits | ((this.bits | that.bits) & ~KINDFLAGS))
       }
 
-    /** The intersection of this flag set and the given flag set */
+    /** The intersection of this flag set and the given flag set 
+     *  TODO(lry): check if resulting flag set has a non-empty kind?
+     */
     def & (that: FlagSet) = FlagSet(bits & that.bits)
 
     /** The intersection of this flag set with the complement of the given flag set */
@@ -89,7 +91,7 @@ object Flags {
     /** The lowest non-kind bit set in this flagset */
     def firstBit: Int = java.lang.Long.numberOfTrailingZeros(bits & ~KINDFLAGS)
 
-    /** The  list of non-empty names of flags with given index idx that are set in this FlagSet */
+    /** The list of non-empty names of flags with given index idx that are set in this FlagSet */
     private def flagString(idx: Int): List[String] =
       if ((bits & (1L << idx)) == 0) Nil
       else {
@@ -112,6 +114,10 @@ object Flags {
   /** A class representing flag sets that should be tested
    *  conjunctively. I.e. for a flag conjunction `fc`,
    *  `x is fc` tests whether `x` contains all flags in `fc`.
+   *
+   * TODO(lry) cannot be a value class because its erause is the same as `FlagSet`,
+   * the overloaded `is` would not work. Maybe rename `is` to `isAny` and `isAll`,
+   * get rid of `FlagConjunction`? Code would also be more explicit.
    */
   case class FlagConjunction(bits: Long) {
     override def toString = FlagSet(bits).toString
@@ -249,7 +255,10 @@ object Flags {
   final val PackageVal = Package.toTermFlags
   final val PackageClass = Package.toTypeFlags
 
-  /** A case class or its companion object */
+  /** A case class or its companion object
+   *  TODO(lry): Is CaseVal set for the companion of a case class? Or for a `case object`?
+   *  Or both? Is CaseClass set for the module class of a `case object`?
+   */
   final val Case = commonFlag(17, "case")
   final val CaseClass = Case.toTypeFlags
   final val CaseVal = Case.toTermFlags

src/dotty/tools/dotc/core/StdNames.scala

@@ -644,6 +644,9 @@ object StdNames {
     def higherKindedTraitName(n: Int) = HigherKinded ++ n.toString
     def higherKindedParamName(n: Int) = HK_PARAM_PREFIX ++ n.toString
 
+    def implClassName(name: Name): TypeName     = (name ++ IMPL_CLASS_SUFFIX).toTypeName
+    def interfaceName(implname: Name): TypeName = (implname dropRight IMPL_CLASS_SUFFIX.length).toTypeName
+
     final val Conforms = encode("<:<")
   }