diff options
Diffstat (limited to 'src/continuations/plugin')
6 files changed, 0 insertions, 1646 deletions
diff --git a/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala b/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala deleted file mode 100644 index 3963447de3..0000000000 --- a/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala +++ /dev/null @@ -1,520 +0,0 @@ -// $Id$ - -package scala.tools.selectivecps - -import scala.tools.nsc.{ Global, Mode } -import scala.tools.nsc.MissingRequirementError - -abstract class CPSAnnotationChecker extends CPSUtils { - val global: Global - import global._ - import analyzer.{AnalyzerPlugin, Typer} - import definitions._ - - //override val verbose = true - @inline override final def vprintln(x: =>Any): Unit = if (verbose) println(x) - - /** - * Checks whether @cps annotations conform - */ - object checker extends AnnotationChecker { - private[CPSAnnotationChecker] def addPlusMarker(tp: Type) = tp withAnnotation newPlusMarker() - private[CPSAnnotationChecker] def addMinusMarker(tp: Type) = tp withAnnotation newMinusMarker() - - private[CPSAnnotationChecker] def cleanPlus(tp: Type) = - removeAttribs(tp, MarkerCPSAdaptPlus, MarkerCPSTypes) - private[CPSAnnotationChecker] def cleanPlusWith(tp: Type)(newAnnots: AnnotationInfo*) = - cleanPlus(tp) withAnnotations newAnnots.toList - - /** Check annotations to decide whether tpe1 <:< tpe2 */ - def annotationsConform(tpe1: Type, tpe2: Type): Boolean = { - if (!cpsEnabled) return true - - vprintln("check annotations: " + tpe1 + " <:< " + tpe2) - - // Nothing is least element, but Any is not the greatest - if (tpe1.typeSymbol eq NothingClass) - return true - - val annots1 = cpsParamAnnotation(tpe1) - val annots2 = cpsParamAnnotation(tpe2) - - // @plus and @minus should only occur at the left, and never together - // TODO: insert check - - // @minus @cps is the same as no annotations - if (hasMinusMarker(tpe1)) - return annots2.isEmpty - - // to handle answer type modification, we must make @plus <:< @cps - if (hasPlusMarker(tpe1) && annots1.isEmpty) - return true - - // @plus @cps will fall through and compare the @cps type args - // @cps parameters must match exactly - if ((annots1 corresponds annots2)(_.atp <:< _.atp)) - return true - - // Need to handle uninstantiated type vars specially: - - // g map (x => x) with expected type List[Int] @cps - // results in comparison ?That <:< List[Int] @cps - - // Instantiating ?That to an annotated type would fail during - // transformation. - - // Instead we force-compare tpe1 <:< tpe2.withoutAnnotations - // to trigger instantiation of the TypeVar to the base type - - // This is a bit unorthodox (we're only supposed to look at - // annotations here) but seems to work. - - if (!annots2.isEmpty && !tpe1.isGround) - return tpe1 <:< tpe2.withoutAnnotations - - false - } - - /** Refine the computed least upper bound of a list of types. - * All this should do is add annotations. */ - override def annotationsLub(tpe: Type, ts: List[Type]): Type = { - if (!cpsEnabled) return tpe - - val annots1 = cpsParamAnnotation(tpe) - val annots2 = ts flatMap cpsParamAnnotation - - if (annots2.nonEmpty) { - val cpsLub = newMarker(global.lub(annots1:::annots2 map (_.atp))) - val tpe1 = if (annots1.nonEmpty) removeAttribs(tpe, MarkerCPSTypes) else tpe - tpe1.withAnnotation(cpsLub) - } - else tpe - } - - /** Refine the bounds on type parameters to the given type arguments. */ - override def adaptBoundsToAnnotations(bounds: List[TypeBounds], tparams: List[Symbol], targs: List[Type]): List[TypeBounds] = { - if (!cpsEnabled) return bounds - - val anyAtCPS = newCpsParamsMarker(NothingTpe, AnyTpe) - if (isFunctionType(tparams.head.owner.tpe_*) || isPartialFunctionType(tparams.head.owner.tpe_*)) { - vprintln("function bound: " + tparams.head.owner.tpe + "/"+bounds+"/"+targs) - if (hasCpsParamTypes(targs.last)) - bounds.reverse match { - case res::b if !hasCpsParamTypes(res.hi) => - (TypeBounds(res.lo, res.hi.withAnnotation(anyAtCPS))::b).reverse - case _ => bounds - } - else - bounds - } - else if (tparams.head.owner == ByNameParamClass) { - vprintln("byname bound: " + tparams.head.owner.tpe + "/"+bounds+"/"+targs) - val TypeBounds(lo, hi) = bounds.head - if (hasCpsParamTypes(targs.head) && !hasCpsParamTypes(hi)) - TypeBounds(lo, hi withAnnotation anyAtCPS) :: Nil - else bounds - } else - bounds - } - } - - object plugin extends AnalyzerPlugin { - - import checker._ - - override def canAdaptAnnotations(tree: Tree, typer: Typer, mode: Mode, pt: Type): Boolean = { - if (!cpsEnabled) return false - vprintln("can adapt annotations? " + tree + " / " + tree.tpe + " / " + mode + " / " + pt) - - val annots1 = cpsParamAnnotation(tree.tpe) - val annots2 = cpsParamAnnotation(pt) - - if (mode.inPatternMode) { - //println("can adapt pattern annotations? " + tree + " / " + tree.tpe + " / " + Integer.toHexString(mode) + " / " + pt) - if (!annots1.isEmpty) { - return true - } - } - -/* - // not precise enough -- still relying on addAnnotations to remove things from ValDef symbols - if (mode.inAllModes(TYPEmode | BYVALmode)) { - if (!annots1.isEmpty) { - return true - } - } -*/ - -/* - this interferes with overloading resolution - if (mode.inByValMode && tree.tpe <:< pt) { - vprintln("already compatible, can't adapt further") - return false - } -*/ - if (mode.inExprMode) { - if ((annots1 corresponds annots2)(_.atp <:< _.atp)) { - vprintln("already same, can't adapt further") - false - } else if (annots1.isEmpty && !annots2.isEmpty && !mode.inByValMode) { - //println("can adapt annotations? " + tree + " / " + tree.tpe + " / " + Integer.toHexString(mode) + " / " + pt) - if (!hasPlusMarker(tree.tpe)) { - // val base = tree.tpe <:< removeAllCPSAnnotations(pt) - // val known = global.analyzer.isFullyDefined(pt) - // println(same + "/" + base + "/" + known) - //val same = annots2 forall { case AnnotationInfo(atp: TypeRef, _, _) => atp.typeArgs(0) =:= atp.typeArgs(1) } - // TBD: use same or not? - //if (same) { - vprintln("yes we can!! (unit)") - true - //} - } else false - } else if (!hasPlusMarker(tree.tpe) && annots1.isEmpty && !annots2.isEmpty && typer.context.inReturnExpr) { - vprintln("checking enclosing method's result type without annotations") - tree.tpe <:< pt.withoutAnnotations - } else if (!hasMinusMarker(tree.tpe) && !annots1.isEmpty && mode.inByValMode) { - val optCpsTypes: Option[(Type, Type)] = cpsParamTypes(tree.tpe) - val optExpectedCpsTypes: Option[(Type, Type)] = cpsParamTypes(pt) - if (optCpsTypes.isEmpty || optExpectedCpsTypes.isEmpty) { - vprintln("yes we can!! (byval)") - true - } else { // check cps param types - val cpsTpes = optCpsTypes.get - val cpsPts = optExpectedCpsTypes.get - // class cpsParam[-B,+C], therefore: - cpsPts._1 <:< cpsTpes._1 && cpsTpes._2 <:< cpsPts._2 - } - } else false - } else false - } - - override def adaptAnnotations(tree: Tree, typer: Typer, mode: Mode, pt: Type): Tree = { - if (!cpsEnabled) return tree - - vprintln("adapt annotations " + tree + " / " + tree.tpe + " / " + mode + " / " + pt) - - val annotsTree = cpsParamAnnotation(tree.tpe) - val annotsExpected = cpsParamAnnotation(pt) - def isMissingExpectedAnnots = annotsTree.isEmpty && annotsExpected.nonEmpty - - // not sure I rephrased this comment correctly: - // replacing `mode.inPatternMode` in the condition below by `mode.inPatternMode || mode.inAllModes(TYPEmode | BYVALmode)` - // doesn't work correctly -- still relying on addAnnotations to remove things from ValDef symbols - if (mode.inPatternMode && annotsTree.nonEmpty) tree modifyType removeAllCPSAnnotations - else if (mode.typingExprNotValue && !hasPlusMarker(tree.tpe) && isMissingExpectedAnnots) { // shiftUnit - // add a marker annotation that will make tree.tpe behave as pt, subtyping wise - // tree will look like having any possible annotation - //println("adapt annotations " + tree + " / " + tree.tpe + " / " + Integer.toHexString(mode) + " / " + pt) - - // CAVEAT: - // for monomorphic answer types we want to have @plus @cps (for better checking) - // for answer type modification we want to have only @plus (because actual answer type may differ from pt) - - val res = tree modifyType (_ withAnnotations newPlusMarker() :: annotsExpected) // needed for #1807 - vprintln("adapted annotations (not by val) of " + tree + " to " + res.tpe) - res - } else if (mode.typingExprByValue && !hasMinusMarker(tree.tpe) && annotsTree.nonEmpty) { // dropping annotation - // add a marker annotation that will make tree.tpe behave as pt, subtyping wise - // tree will look like having no annotation - val res = tree modifyType addMinusMarker - vprintln("adapted annotations (by val) of " + tree + " to " + res.tpe) - res - } else if (typer.context.inReturnExpr && !hasPlusMarker(tree.tpe) && isMissingExpectedAnnots) { - // add a marker annotation that will make tree.tpe behave as pt, subtyping wise - // tree will look like having any possible annotation - - // note 1: we are only adding a plus marker if the method's result type is a cps type - // (annotsExpected.nonEmpty == cpsParamAnnotation(pt).nonEmpty) - // note 2: we are not adding the expected cps annotations, since they will be added - // by adaptTypeOfReturn (see below). - val res = tree modifyType (_ withAnnotation newPlusMarker()) - vprintln("adapted annotations (return) of " + tree + " to " + res.tpe) - res - } else tree - } - - /** Returns an adapted type for a return expression if the method's result type (pt) is a CPS type. - * Otherwise, it returns the `default` type (`typedReturn` passes `NothingTpe`). - * - * A return expression in a method that has a CPS result type is an error unless the return - * is in tail position. Therefore, we are making sure that only the types of return expressions - * are adapted which will either be removed, or lead to an error. - */ - override def pluginsTypedReturn(default: Type, typer: Typer, tree: Return, pt: Type): Type = { - val expr = tree.expr - // only adapt if method's result type (pt) is cps type - val annots = cpsParamAnnotation(pt) - if (annots.nonEmpty) { - // return type of `expr` without plus marker, but only if it doesn't have other cps annots - if (hasPlusMarker(expr.tpe) && !hasCpsParamTypes(expr.tpe)) - expr.setType(removeAttribs(expr.tpe, MarkerCPSAdaptPlus)) - expr.tpe - } else default - } - - def updateAttributesFromChildren(tpe: Type, childAnnots: List[AnnotationInfo], byName: List[Tree]): Type = { - tpe match { - // Would need to push annots into each alternative of overloaded type - // But we can't, since alternatives aren't types but symbols, which we - // can't change (we'd be affecting symbols globally) - /* - case OverloadedType(pre, alts) => - OverloadedType(pre, alts.map((sym: Symbol) => updateAttributes(pre.memberType(sym), annots))) - */ - case OverloadedType(pre, alts) => tpe //reconstruct correct annotations later - case MethodType(params, restpe) => tpe - case PolyType(params, restpe) => tpe - case _ => - assert(childAnnots forall (_ matches MarkerCPSTypes), childAnnots) - /* - [] + [] = [] - plus + [] = plus - cps + [] = cps - plus cps + [] = plus cps - minus cps + [] = minus cps - synth cps + [] = synth cps // <- synth on left - does it happen? - - [] + cps = cps - plus + cps = synth cps - cps + cps = cps! <- lin - plus cps + cps = synth cps! <- unify - minus cps + cps = minus cps! <- lin - synth cps + cps = synth cps! <- unify - */ - - val plus = hasPlusMarker(tpe) || ( - hasCpsParamTypes(tpe) - && byName.nonEmpty - && (byName forall (t => hasPlusMarker(t.tpe))) - ) - - // move @plus annotations outward from by-name children - if (childAnnots.isEmpty) return { - if (plus) { // @plus or @plus @cps - byName foreach (_ modifyType cleanPlus) - addPlusMarker(tpe) - } - else tpe - } - - val annots1 = cpsParamAnnotation(tpe) - - if (annots1.isEmpty) { // nothing or @plus - cleanPlusWith(tpe)(newSynthMarker(), linearize(childAnnots)) - } - else { - val annot1 = single(annots1) - if (plus) { // @plus @cps - val annot2 = linearize(childAnnots) - - if (annot2.atp <:< annot1.atp) { - try cleanPlusWith(tpe)(newSynthMarker(), annot2) - finally byName foreach (_ modifyType cleanPlus) - } - else throw new TypeError(annot2 + " is not a subtype of " + annot1) - } - else if (hasSynthMarker(tpe)) { // @synth @cps - val annot2 = linearize(childAnnots) - if (annot2.atp <:< annot1.atp) - cleanPlusWith(tpe)(annot2) - else - throw new TypeError(annot2 + " is not a subtype of " + annot1) - } - else // @cps - cleanPlusWith(tpe)(linearize(childAnnots:::annots1)) - } - } - } - - def transArgList(fun: Tree, args: List[Tree]): List[List[Tree]] = { - val formals = fun.tpe.paramTypes - val overshoot = args.length - formals.length - - for ((a,tp) <- args.zip(formals ::: List.fill(overshoot)(NoType))) yield { - tp match { - case TypeRef(_, ByNameParamClass, List(elemtp)) => - Nil // TODO: check conformance?? - case _ => - List(a) - } - } - } - - - def transStms(stms: List[Tree]): List[Tree] = stms match { - case ValDef(mods, name, tpt, rhs)::xs => - rhs::transStms(xs) - case Assign(lhs, rhs)::xs => - rhs::transStms(xs) - case x::xs => - x::transStms(xs) - case Nil => - Nil - } - - def single(xs: List[AnnotationInfo]) = xs match { - case List(x) => x - case _ => - global.globalError("not a single cps annotation: " + xs) - xs(0) - } - - def emptyOrSingleList(xs: List[AnnotationInfo]) = if (xs.isEmpty) Nil else List(single(xs)) - - def transChildrenInOrder(tree: Tree, tpe: Type, childTrees: List[Tree], byName: List[Tree]) = { - def inspect(t: Tree): List[AnnotationInfo] = { - if (t.tpe eq null) Nil else { - val extra: List[AnnotationInfo] = t.tpe match { - case _: MethodType | _: PolyType | _: OverloadedType => - // method types, poly types and overloaded types do not obtain cps annotions by propagation - // need to reconstruct transitively from their children. - t match { - case Select(qual, name) => inspect(qual) - case Apply(fun, args) => (fun::(transArgList(fun,args).flatten)) flatMap inspect - case TypeApply(fun, args) => (fun::(transArgList(fun,args).flatten)) flatMap inspect - case _ => Nil - } - case _ => Nil - } - - val types = cpsParamAnnotation(t.tpe) - // TODO: check that it has been adapted and if so correctly - extra ++ emptyOrSingleList(types) - } - } - val children = childTrees flatMap inspect - - val newtpe = updateAttributesFromChildren(tpe, children, byName) - - if (!newtpe.annotations.isEmpty) - vprintln("[checker] inferred " + tree + " / " + tpe + " ===> "+ newtpe) - - newtpe - } - - /** Modify the type that has thus far been inferred - * for a tree. All this should do is add annotations. */ - - override def pluginsTyped(tpe: Type, typer: Typer, tree: Tree, mode: Mode, pt: Type): Type = { - if (!cpsEnabled) { - val report = try hasCpsParamTypes(tpe) catch { case _: MissingRequirementError => false } - if (report) - global.reporter.error(tree.pos, "this code must be compiled with the Scala continuations plugin enabled") - - return tpe - } - -// if (tree.tpe.hasAnnotation(MarkerCPSAdaptPlus)) -// println("addAnnotation " + tree + "/" + tpe) - - tree match { - - case Apply(fun @ Select(qual, name), args) if fun.isTyped => - - // HACK: With overloaded methods, fun will never get annotated. This is because - // the 'overloaded' type gets annotated, but not the alternatives (among which - // fun's type is chosen) - - vprintln("[checker] checking select apply " + tree + "/" + tpe) - - transChildrenInOrder(tree, tpe, qual::(transArgList(fun, args).flatten), Nil) - - case Apply(TypeApply(fun @ Select(qual, name), targs), args) if fun.isTyped => // not trigge - - vprintln("[checker] checking select apply type-apply " + tree + "/" + tpe) - - transChildrenInOrder(tree, tpe, qual::(transArgList(fun, args).flatten), Nil) - - case TypeApply(fun @ Select(qual, name), args) if fun.isTyped => - def stripNullaryMethodType(tp: Type) = tp match { case NullaryMethodType(restpe) => restpe case tp => tp } - vprintln("[checker] checking select type-apply " + tree + "/" + tpe) - - transChildrenInOrder(tree, stripNullaryMethodType(tpe), List(qual, fun), Nil) - - case Apply(fun, args) if fun.isTyped => - - vprintln("[checker] checking unknown apply " + tree + "/" + tpe) - - transChildrenInOrder(tree, tpe, fun::(transArgList(fun, args).flatten), Nil) - - case TypeApply(fun, args) => - - vprintln("[checker] checking unknown type apply " + tree + "/" + tpe) - - transChildrenInOrder(tree, tpe, List(fun), Nil) - - case Select(qual, name) if qual.isTyped => - - vprintln("[checker] checking select " + tree + "/" + tpe) - - // straightforward way is problematic (see select.scala and Test2.scala) - // transChildrenInOrder(tree, tpe, List(qual), Nil) - - // the problem is that qual may be of type OverloadedType (or MethodType) and - // we cannot safely annotate these. so we just ignore these cases and - // clean up later in the Apply/TypeApply trees. - - if (hasCpsParamTypes(qual.tpe)) { - // however there is one special case: - // if it's a method without parameters, just apply it. normally done in adapt, but - // we have to do it here so we don't lose the cps information (wouldn't trigger our - // adapt and there is no Apply/TypeApply created) - tpe match { - case NullaryMethodType(restpe) => - //println("yep: " + restpe + "," + restpe.getClass) - transChildrenInOrder(tree, restpe, List(qual), Nil) - case _ : PolyType => tpe - case _ : MethodType => tpe - case _ : OverloadedType => tpe - case _ => - transChildrenInOrder(tree, tpe, List(qual), Nil) - } - } else - tpe - - case If(cond, thenp, elsep) => - transChildrenInOrder(tree, tpe, List(cond), List(thenp, elsep)) - - case Match(select, cases) => - transChildrenInOrder(tree, tpe, List(select), cases:::(cases map { case CaseDef(_, _, body) => body })) - - case Try(block, catches, finalizer) => - val tpe1 = transChildrenInOrder(tree, tpe, Nil, block::catches:::(catches map { case CaseDef(_, _, body) => body })) - - val annots = cpsParamAnnotation(tpe1) - if (annots.nonEmpty) { - val ann = single(annots) - val (atp0, atp1) = annTypes(ann) - if (!(atp0 =:= atp1)) - throw new TypeError("only simple cps types allowed in try/catch blocks (found: " + tpe1 + ")") - if (!finalizer.isEmpty) // no finalizers allowed. see explanation in SelectiveCPSTransform - reporter.error(tree.pos, "try/catch blocks that use continuations cannot have finalizers") - } - tpe1 - - case Block(stms, expr) => - // if any stm has annotation, so does block - transChildrenInOrder(tree, tpe, transStms(stms), List(expr)) - - case ValDef(mods, name, tpt, rhs) => - vprintln("[checker] checking valdef " + name + "/"+tpe+"/"+tpt+"/"+tree.symbol.tpe) - // ValDef symbols must *not* have annotations! - // lazy vals are currently not supported - // but if we erase here all annotations, compiler will complain only - // when generating bytecode. - // This way lazy vals will be reported as unsupported feature later rather than weird type error. - if (hasAnswerTypeAnn(tree.symbol.info) && !mods.isLazy) { // is it okay to modify sym here? - vprintln("removing annotation from sym " + tree.symbol + "/" + tree.symbol.tpe + "/" + tpt) - tpt modifyType removeAllCPSAnnotations - tree.symbol modifyInfo removeAllCPSAnnotations - } - tpe - - case _ => - tpe - } - - - } - } -} diff --git a/src/continuations/plugin/scala/tools/selectivecps/CPSUtils.scala b/src/continuations/plugin/scala/tools/selectivecps/CPSUtils.scala deleted file mode 100644 index 98d0695865..0000000000 --- a/src/continuations/plugin/scala/tools/selectivecps/CPSUtils.scala +++ /dev/null @@ -1,137 +0,0 @@ -// $Id$ - -package scala.tools.selectivecps - -import scala.tools.nsc.Global - -trait CPSUtils { - val global: Global - import global._ - - val cpsEnabled: Boolean - val verbose: Boolean = System.getProperty("cpsVerbose", "false") == "true" - def vprintln(x: =>Any): Unit = if (verbose) println(x) - - object cpsNames { - val catches = newTermName("$catches") - val ex = newTermName("$ex") - val flatMapCatch = newTermName("flatMapCatch") - val getTrivialValue = newTermName("getTrivialValue") - val isTrivial = newTermName("isTrivial") - val reify = newTermName("reify") - val reifyR = newTermName("reifyR") - val shift = newTermName("shift") - val shiftR = newTermName("shiftR") - val shiftSuffix = newTermName("$shift") - val shiftUnit0 = newTermName("shiftUnit0") - val shiftUnit = newTermName("shiftUnit") - val shiftUnitR = newTermName("shiftUnitR") - } - - lazy val MarkerCPSSym = rootMirror.getRequiredClass("scala.util.continuations.cpsSym") - lazy val MarkerCPSTypes = rootMirror.getRequiredClass("scala.util.continuations.cpsParam") - lazy val MarkerCPSSynth = rootMirror.getRequiredClass("scala.util.continuations.cpsSynth") - lazy val MarkerCPSAdaptPlus = rootMirror.getRequiredClass("scala.util.continuations.cpsPlus") - lazy val MarkerCPSAdaptMinus = rootMirror.getRequiredClass("scala.util.continuations.cpsMinus") - - lazy val Context = rootMirror.getRequiredClass("scala.util.continuations.ControlContext") - lazy val ModCPS = rootMirror.getPackage("scala.util.continuations") - - lazy val MethShiftUnit = definitions.getMember(ModCPS, cpsNames.shiftUnit) - lazy val MethShiftUnit0 = definitions.getMember(ModCPS, cpsNames.shiftUnit0) - lazy val MethShiftUnitR = definitions.getMember(ModCPS, cpsNames.shiftUnitR) - lazy val MethShift = definitions.getMember(ModCPS, cpsNames.shift) - lazy val MethShiftR = definitions.getMember(ModCPS, cpsNames.shiftR) - lazy val MethReify = definitions.getMember(ModCPS, cpsNames.reify) - lazy val MethReifyR = definitions.getMember(ModCPS, cpsNames.reifyR) - - lazy val allCPSAnnotations = List(MarkerCPSSym, MarkerCPSTypes, MarkerCPSSynth, - MarkerCPSAdaptPlus, MarkerCPSAdaptMinus) - - // TODO - needed? Can these all use the same annotation info? - protected def newSynthMarker() = newMarker(MarkerCPSSynth) - protected def newPlusMarker() = newMarker(MarkerCPSAdaptPlus) - protected def newMinusMarker() = newMarker(MarkerCPSAdaptMinus) - protected def newMarker(tpe: Type): AnnotationInfo = AnnotationInfo marker tpe - protected def newMarker(sym: Symbol): AnnotationInfo = AnnotationInfo marker sym.tpe - - protected def newCpsParamsMarker(tp1: Type, tp2: Type) = - newMarker(appliedType(MarkerCPSTypes, tp1, tp2)) - - // annotation checker - - protected def annTypes(ann: AnnotationInfo): (Type, Type) = { - val tp0 :: tp1 :: Nil = ann.atp.dealiasWiden.typeArgs - ((tp0, tp1)) - } - protected def hasMinusMarker(tpe: Type) = tpe hasAnnotation MarkerCPSAdaptMinus - protected def hasPlusMarker(tpe: Type) = tpe hasAnnotation MarkerCPSAdaptPlus - protected def hasSynthMarker(tpe: Type) = tpe hasAnnotation MarkerCPSSynth - protected def hasCpsParamTypes(tpe: Type) = tpe hasAnnotation MarkerCPSTypes - protected def cpsParamTypes(tpe: Type) = tpe getAnnotation MarkerCPSTypes map annTypes - - def filterAttribs(tpe:Type, cls:Symbol) = - tpe.annotations filter (_ matches cls) - - def removeAttribs(tpe: Type, classes: Symbol*) = - tpe filterAnnotations (ann => !(classes exists (ann matches _))) - - def removeAllCPSAnnotations(tpe: Type) = removeAttribs(tpe, allCPSAnnotations:_*) - - def cpsParamAnnotation(tpe: Type) = filterAttribs(tpe, MarkerCPSTypes) - - def linearize(ann: List[AnnotationInfo]): AnnotationInfo = { - ann reduceLeft { (a, b) => - val (u0,v0) = annTypes(a) - val (u1,v1) = annTypes(b) - // vprintln("check lin " + a + " andThen " + b) - - if (v1 <:< u0) - newCpsParamsMarker(u1, v0) - else - throw new TypeError("illegal answer type modification: " + a + " andThen " + b) - } - } - - // anf transform - - def getExternalAnswerTypeAnn(tp: Type) = { - cpsParamTypes(tp) orElse { - if (hasPlusMarker(tp)) - global.warning("trying to instantiate type " + tp + " to unknown cps type") - None - } - } - - def getAnswerTypeAnn(tp: Type): Option[(Type, Type)] = - cpsParamTypes(tp) filterNot (_ => hasPlusMarker(tp)) - - def hasAnswerTypeAnn(tp: Type) = - hasCpsParamTypes(tp) && !hasPlusMarker(tp) - - def updateSynthFlag(tree: Tree) = { // remove annotations if *we* added them (@synth present) - if (hasSynthMarker(tree.tpe)) { - log("removing annotation from " + tree) - tree modifyType removeAllCPSAnnotations - } else - tree - } - - type CPSInfo = Option[(Type,Type)] - - def linearize(a: CPSInfo, b: CPSInfo)(implicit unit: CompilationUnit, pos: Position): CPSInfo = { - (a,b) match { - case (Some((u0,v0)), Some((u1,v1))) => - vprintln("check lin " + a + " andThen " + b) - if (!(v1 <:< u0)) { - unit.error(pos,"cannot change answer type in composition of cps expressions " + - "from " + u1 + " to " + v0 + " because " + v1 + " is not a subtype of " + u0 + ".") - throw new Exception("check lin " + a + " andThen " + b) - } - Some((u1,v0)) - case (Some(_), _) => a - case (_, Some(_)) => b - case _ => None - } - } -} diff --git a/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala b/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala deleted file mode 100644 index ae95a1bdac..0000000000 --- a/src/continuations/plugin/scala/tools/selectivecps/SelectiveANFTransform.scala +++ /dev/null @@ -1,545 +0,0 @@ -// $Id$ - -package scala.tools.selectivecps - -import scala.tools.nsc.transform._ -import scala.tools.nsc.symtab._ -import scala.tools.nsc.plugins._ - -/** - * In methods marked @cps, explicitly name results of calls to other @cps methods - */ -abstract class SelectiveANFTransform extends PluginComponent with Transform with - TypingTransformers with CPSUtils { - // inherits abstract value `global` and class `Phase` from Transform - - import global._ // the global environment - import definitions._ // standard classes and methods - import typer.atOwner // methods to type trees - - override def description = "ANF pre-transform for @cps" - - /** the following two members override abstract members in Transform */ - val phaseName: String = "selectiveanf" - - protected def newTransformer(unit: CompilationUnit): Transformer = - new ANFTransformer(unit) - - class ANFTransformer(unit: CompilationUnit) extends TypingTransformer(unit) { - - implicit val _unit = unit // allow code in CPSUtils.scala to report errors - var cpsAllowed: Boolean = false // detect cps code in places we do not handle (yet) - - object RemoveTailReturnsTransformer extends Transformer { - override def transform(tree: Tree): Tree = tree match { - case Block(stms, r @ Return(expr)) => - treeCopy.Block(tree, stms, expr) - - case Block(stms, expr) => - treeCopy.Block(tree, stms, transform(expr)) - - case If(cond, r1 @ Return(thenExpr), r2 @ Return(elseExpr)) => - treeCopy.If(tree, cond, transform(thenExpr), transform(elseExpr)) - - case If(cond, r1 @ Return(thenExpr), elseExpr) => - treeCopy.If(tree, cond, transform(thenExpr), transform(elseExpr)) - - case If(cond, thenExpr, r2 @ Return(elseExpr)) => - treeCopy.If(tree, cond, transform(thenExpr), transform(elseExpr)) - - case If(cond, thenExpr, elseExpr) => - treeCopy.If(tree, cond, transform(thenExpr), transform(elseExpr)) - - case Try(block, catches, finalizer) => - treeCopy.Try(tree, - transform(block), - (catches map (t => transform(t))).asInstanceOf[List[CaseDef]], - transform(finalizer)) - - case CaseDef(pat, guard, r @ Return(expr)) => - treeCopy.CaseDef(tree, pat, guard, expr) - - case CaseDef(pat, guard, body) => - treeCopy.CaseDef(tree, pat, guard, transform(body)) - - case Return(_) => - unit.error(tree.pos, "return expressions in CPS code must be in tail position") - tree - - case _ => - super.transform(tree) - } - } - - def removeTailReturns(body: Tree): Tree = { - // support body with single return expression - body match { - case Return(expr) => expr - case _ => RemoveTailReturnsTransformer.transform(body) - } - } - - override def transform(tree: Tree): Tree = { - if (!cpsEnabled) return tree - - tree match { - - // Maybe we should further generalize the transform and move it over - // to the regular Transformer facility. But then, actual and required cps - // state would need more complicated (stateful!) tracking. - - // Making the default case use transExpr(tree, None, None) instead of - // calling super.transform() would be a start, but at the moment, - // this would cause infinite recursion. But we could remove the - // ValDef case here. - - case dd @ DefDef(mods, name, tparams, vparamss, tpt, rhs0) => - debuglog("transforming " + dd.symbol) - - atOwner(dd.symbol) { - val rhs = - if (cpsParamTypes(tpt.tpe).nonEmpty) removeTailReturns(rhs0) - else rhs0 - val rhs1 = transExpr(rhs, None, getExternalAnswerTypeAnn(tpt.tpe))(getExternalAnswerTypeAnn(tpt.tpe).isDefined) - - debuglog("result "+rhs1) - debuglog("result is of type "+rhs1.tpe) - - treeCopy.DefDef(dd, mods, name, transformTypeDefs(tparams), transformValDefss(vparamss), - transform(tpt), rhs1) - } - - case ff @ Function(vparams, body) => - debuglog("transforming anon function " + ff.symbol) - - atOwner(ff.symbol) { - - //val body1 = transExpr(body, None, getExternalAnswerTypeAnn(body.tpe)) - - // need to special case partial functions: if expected type is @cps - // but all cases are pure, then we would transform - // { x => x match { case A => ... }} to - // { x => shiftUnit(x match { case A => ... })} - // which Uncurry cannot handle (see function6.scala) - // thus, we push down the shiftUnit to each of the case bodies - - val ext = getExternalAnswerTypeAnn(body.tpe) - val pureBody = getAnswerTypeAnn(body.tpe).isEmpty - implicit val isParentImpure = ext.isDefined - - def transformPureMatch(tree: Tree, selector: Tree, cases: List[CaseDef]) = { - val caseVals = cases map { case cd @ CaseDef(pat, guard, body) => - // if (!hasPlusMarker(body.tpe)) body modifyType (_ withAnnotation newPlusMarker()) // TODO: to avoid warning - val bodyVal = transExpr(body, None, ext) // ??? triggers "cps-transformed unexpectedly" warning in transTailValue - treeCopy.CaseDef(cd, transform(pat), transform(guard), bodyVal) - } - treeCopy.Match(tree, transform(selector), caseVals) - } - - def transformPureVirtMatch(body: Block, selDef: ValDef, cases: List[Tree], matchEnd: Tree) = { - val stats = transform(selDef) :: (cases map (transExpr(_, None, ext))) - treeCopy.Block(body, stats, transExpr(matchEnd, None, ext)) - } - - val body1 = body match { - case Match(selector, cases) if ext.isDefined && pureBody => - transformPureMatch(body, selector, cases) - - // virtpatmat switch - case Block(List(selDef: ValDef), mat@Match(selector, cases)) if ext.isDefined && pureBody => - treeCopy.Block(body, List(transform(selDef)), transformPureMatch(mat, selector, cases)) - - // virtpatmat - case b@Block(matchStats@((selDef: ValDef) :: cases), matchEnd) if ext.isDefined && pureBody && (matchStats forall treeInfo.hasSynthCaseSymbol) => - transformPureVirtMatch(b, selDef, cases, matchEnd) - - // virtpatmat that stores the scrut separately -- TODO: can we eliminate this case?? - case Block(List(selDef0: ValDef), mat@Block(matchStats@((selDef: ValDef) :: cases), matchEnd)) if ext.isDefined && pureBody && (matchStats forall treeInfo.hasSynthCaseSymbol)=> - treeCopy.Block(body, List(transform(selDef0)), transformPureVirtMatch(mat, selDef, cases, matchEnd)) - - case _ => - transExpr(body, None, ext) - } - - debuglog("anf result "+body1+"\nresult is of type "+body1.tpe) - - treeCopy.Function(ff, transformValDefs(vparams), body1) - } - - case vd @ ValDef(mods, name, tpt, rhs) => // object-level valdefs - debuglog("transforming valdef " + vd.symbol) - - if (getExternalAnswerTypeAnn(tpt.tpe).isEmpty) { - - atOwner(vd.symbol) { - - val rhs1 = transExpr(rhs, None, None) - - treeCopy.ValDef(vd, mods, name, transform(tpt), rhs1) - } - } else { - unit.error(tree.pos, "cps annotations not allowed on by-value parameters or value definitions") - super.transform(tree) - } - - case TypeTree() => - // circumvent cpsAllowed here - super.transform(tree) - - case Apply(_,_) => - // this allows reset { ... } in object constructors - // it's kind of a hack to put it here (see note above) - transExpr(tree, None, None) - - case _ => - if (hasAnswerTypeAnn(tree.tpe)) { - if (!cpsAllowed) { - if (tree.symbol.isLazy) - unit.error(tree.pos, "implementation restriction: cps annotations not allowed on lazy value definitions") - else - unit.error(tree.pos, "cps code not allowed here / " + tree.getClass + " / " + tree) - } - log(tree) - } - - cpsAllowed = false - super.transform(tree) - } - } - - - def transExpr(tree: Tree, cpsA: CPSInfo, cpsR: CPSInfo)(implicit isAnyParentImpure: Boolean = false): Tree = { - transTailValue(tree, cpsA, cpsR)(cpsR.isDefined || isAnyParentImpure) match { - case (Nil, b) => b - case (a, b) => - treeCopy.Block(tree, a,b) - } - } - - - def transArgList(fun: Tree, args: List[Tree], cpsA: CPSInfo)(implicit isAnyParentImpure: Boolean): (List[List[Tree]], List[Tree], CPSInfo) = { - val formals = fun.tpe.paramTypes - val overshoot = args.length - formals.length - - var spc: CPSInfo = cpsA - - val (stm,expr) = (for ((a,tp) <- args.zip(formals ::: List.fill(overshoot)(NoType))) yield { - tp match { - case TypeRef(_, ByNameParamClass, List(elemtp)) => - // note that we're not passing just isAnyParentImpure - (Nil, transExpr(a, None, getAnswerTypeAnn(elemtp))(getAnswerTypeAnn(elemtp).isDefined || isAnyParentImpure)) - case _ => - val (valStm, valExpr, valSpc) = transInlineValue(a, spc) - spc = valSpc - (valStm, valExpr) - } - }).unzip - - (stm,expr,spc) - } - - - // precondition: cpsR.isDefined "implies" isAnyParentImpure - def transValue(tree: Tree, cpsA: CPSInfo, cpsR: CPSInfo)(implicit isAnyParentImpure: Boolean): (List[Tree], Tree, CPSInfo) = { - // return value: (stms, expr, spc), where spc is CPSInfo after stms but *before* expr - implicit val pos = tree.pos - tree match { - case Block(stms, expr) => - val (cpsA2, cpsR2) = (cpsA, linearize(cpsA, getAnswerTypeAnn(tree.tpe))) // tbd - // val (cpsA2, cpsR2) = (None, getAnswerTypeAnn(tree.tpe)) - - val (a, b) = transBlock(stms, expr, cpsA2, cpsR2)(cpsR2.isDefined || isAnyParentImpure) - val tree1 = (treeCopy.Block(tree, a, b)) // no updateSynthFlag here!!! - - (Nil, tree1, cpsA) - - case If(cond, thenp, elsep) => - /* possible situations: - cps before (cpsA) - cps in condition (spc) <-- synth flag set if *only* here! - cps in (one or both) branches */ - val (condStats, condVal, spc) = transInlineValue(cond, cpsA) - val (cpsA2, cpsR2) = if (hasSynthMarker(tree.tpe)) - (spc, linearize(spc, getAnswerTypeAnn(tree.tpe))) else - (None, getAnswerTypeAnn(tree.tpe)) // if no cps in condition, branches must conform to tree.tpe directly - val thenVal = transExpr(thenp, cpsA2, cpsR2)(cpsR2.isDefined || isAnyParentImpure) - val elseVal = transExpr(elsep, cpsA2, cpsR2)(cpsR2.isDefined || isAnyParentImpure) - - // check that then and else parts agree (not necessary any more, but left as sanity check) - if (cpsR.isDefined) { - if (elsep == EmptyTree) - unit.error(tree.pos, "always need else part in cps code") - } - if (hasAnswerTypeAnn(thenVal.tpe) != hasAnswerTypeAnn(elseVal.tpe)) { - unit.error(tree.pos, "then and else parts must both be cps code or neither of them") - } - - (condStats, updateSynthFlag(treeCopy.If(tree, condVal, thenVal, elseVal)), spc) - - case Match(selector, cases) => - val (selStats, selVal, spc) = transInlineValue(selector, cpsA) - val (cpsA2, cpsR2) = - if (hasSynthMarker(tree.tpe)) (spc, linearize(spc, getAnswerTypeAnn(tree.tpe))) - else (None, getAnswerTypeAnn(tree.tpe)) - - val caseVals = cases map { case cd @ CaseDef(pat, guard, body) => - val bodyVal = transExpr(body, cpsA2, cpsR2)(cpsR2.isDefined || isAnyParentImpure) - treeCopy.CaseDef(cd, transform(pat), transform(guard), bodyVal) - } - - (selStats, updateSynthFlag(treeCopy.Match(tree, selVal, caseVals)), spc) - - // this is utterly broken: LabelDefs need to be considered together when transforming them to DefDefs: - // suppose a Block {L1; ... ; LN} - // this should become {D1def ; ... ; DNdef ; D1()} - // where D$idef = def L$i(..) = {L$i.body; L${i+1}(..)} - - case ldef @ LabelDef(name, params, rhs) => - // println("trans LABELDEF "+(name, params, tree.tpe, hasAnswerTypeAnn(tree.tpe))) - // TODO why does the labeldef's type have a cpsMinus annotation, whereas the rhs does not? (BYVALmode missing/too much somewhere?) - if (hasAnswerTypeAnn(tree.tpe)) { - // currentOwner.newMethod(name, tree.pos, Flags.SYNTHETIC) setInfo ldef.symbol.info - val sym = ldef.symbol resetFlag Flags.LABEL - val rhs1 = rhs //new TreeSymSubstituter(List(ldef.symbol), List(sym)).transform(rhs) - val rhsVal = transExpr(rhs1, None, getAnswerTypeAnn(tree.tpe))(getAnswerTypeAnn(tree.tpe).isDefined || isAnyParentImpure) changeOwner (currentOwner -> sym) - - val stm1 = localTyper.typed(DefDef(sym, rhsVal)) - // since virtpatmat does not rely on fall-through, don't call the labels it emits - // transBlock will take care of calling the first label - // calling each labeldef is wrong, since some labels may be jumped over - // we can get away with this for now since the only other labels we emit are for tailcalls/while loops, - // which do not have consecutive labeldefs (and thus fall-through is irrelevant) - if (treeInfo.hasSynthCaseSymbol(ldef)) (List(stm1), localTyper.typed{Literal(Constant(()))}, cpsA) - else { - assert(params.isEmpty, "problem in ANF transforming label with non-empty params "+ ldef) - (List(stm1), localTyper.typed{Apply(Ident(sym), List())}, cpsA) - } - } else { - val rhsVal = transExpr(rhs, None, None) - (Nil, updateSynthFlag(treeCopy.LabelDef(tree, name, params, rhsVal)), cpsA) - } - - - case Try(block, catches, finalizer) => - val blockVal = transExpr(block, cpsA, cpsR) - - val catchVals = for { - cd @ CaseDef(pat, guard, body) <- catches - bodyVal = transExpr(body, cpsA, cpsR) - } yield { - treeCopy.CaseDef(cd, transform(pat), transform(guard), bodyVal) - } - - val finallyVal = transExpr(finalizer, None, None) // for now, no cps in finally - - (Nil, updateSynthFlag(treeCopy.Try(tree, blockVal, catchVals, finallyVal)), cpsA) - - case Assign(lhs, rhs) => - // allow cps code in rhs only - val (stms, expr, spc) = transInlineValue(rhs, cpsA) - (stms, updateSynthFlag(treeCopy.Assign(tree, transform(lhs), expr)), spc) - - case Return(expr0) => - if (isAnyParentImpure) - unit.error(tree.pos, "return expression not allowed, since method calls CPS method") - val (stms, expr, spc) = transInlineValue(expr0, cpsA) - (stms, updateSynthFlag(treeCopy.Return(tree, expr)), spc) - - case Throw(expr0) => - val (stms, expr, spc) = transInlineValue(expr0, cpsA) - (stms, updateSynthFlag(treeCopy.Throw(tree, expr)), spc) - - case Typed(expr0, tpt) => - // TODO: should x: A @cps[B,C] have a special meaning? - // type casts used in different ways (see match2.scala, #3199) - val (stms, expr, spc) = transInlineValue(expr0, cpsA) - val tpt1 = if (treeInfo.isWildcardStarArg(tree)) tpt else - treeCopy.TypeTree(tpt).setType(removeAllCPSAnnotations(tpt.tpe)) -// (stms, updateSynthFlag(treeCopy.Typed(tree, expr, tpt1)), spc) - (stms, treeCopy.Typed(tree, expr, tpt1).setType(removeAllCPSAnnotations(tree.tpe)), spc) - - case TypeApply(fun, args) => - val (stms, expr, spc) = transInlineValue(fun, cpsA) - (stms, updateSynthFlag(treeCopy.TypeApply(tree, expr, args)), spc) - - case Select(qual, name) => - val (stms, expr, spc) = transInlineValue(qual, cpsA) - (stms, updateSynthFlag(treeCopy.Select(tree, expr, name)), spc) - - case Apply(fun, args) => - val (funStm, funExpr, funSpc) = transInlineValue(fun, cpsA) - val (argStm, argExpr, argSpc) = transArgList(fun, args, funSpc) - - (funStm ::: (argStm.flatten), updateSynthFlag(treeCopy.Apply(tree, funExpr, argExpr)), - argSpc) - - case _ => - cpsAllowed = true - (Nil, transform(tree), cpsA) - } - } - - // precondition: cpsR.isDefined "implies" isAnyParentImpure - def transTailValue(tree: Tree, cpsA: CPSInfo, cpsR: CPSInfo)(implicit isAnyParentImpure: Boolean): (List[Tree], Tree) = { - - val (stms, expr, spc) = transValue(tree, cpsA, cpsR) - - val bot = linearize(spc, getAnswerTypeAnn(expr.tpe))(unit, tree.pos) - - val plainTpe = removeAllCPSAnnotations(expr.tpe) - - if (cpsR.isDefined && !bot.isDefined) { - - if (!expr.isEmpty && (expr.tpe.typeSymbol ne NothingClass)) { - // must convert! - debuglog("cps type conversion (has: " + cpsA + "/" + spc + "/" + expr.tpe + ")") - debuglog("cps type conversion (expected: " + cpsR.get + "): " + expr) - - if (!hasPlusMarker(expr.tpe)) - unit.warning(tree.pos, "expression " + tree + " is cps-transformed unexpectedly") - - try { - val Some((a, b)) = cpsR - /* Since shiftUnit is bounded [A,B,C>:B] this may not typecheck - * if C is overly specific. So if !(B <:< C), call shiftUnit0 - * instead, which takes only two type arguments. - */ - val conforms = a <:< b - val call = localTyper.typedPos(tree.pos)( - Apply( - TypeApply( - gen.mkAttributedRef( if (conforms) MethShiftUnit else MethShiftUnit0 ), - List(TypeTree(plainTpe), TypeTree(a)) ++ ( if (conforms) List(TypeTree(b)) else Nil ) - ), - List(expr) - ) - ) - // This is today's sick/meaningless heuristic for spotting breakdown so - // we don't proceed until stack traces start draping themselves over everything. - // If there are wildcard types in the tree and B == Nothing, something went wrong. - // (I thought WildcardTypes would be enough, but nope. 'reset0 { 0 }' has them.) - // - // Code as simple as reset((_: String).length) - // will crash meaninglessly without this check. See SI-3718. - // - // TODO - obviously this should be done earlier, differently, or with - // a more skilled hand. Most likely, all three. - if ((b.typeSymbol eq NothingClass) && call.tpe.exists(_ eq WildcardType)) - unit.error(tree.pos, "cannot cps-transform malformed (possibly in shift/reset placement) expression") - else - return ((stms, call)) - } - catch { - case ex:TypeError => - unit.error(ex.pos, "cannot cps-transform expression " + tree + ": " + ex.msg) - } - } - - } else if (!cpsR.isDefined && bot.isDefined) { - // error! - debuglog("cps type error: " + expr) - //println("cps type error: " + expr + "/" + expr.tpe + "/" + getAnswerTypeAnn(expr.tpe)) - - //println(cpsR + "/" + spc + "/" + bot) - - unit.error(tree.pos, "found cps expression in non-cps position") - } else { - // all is well - - if (hasPlusMarker(expr.tpe)) { - unit.warning(tree.pos, "expression " + expr + " of type " + expr.tpe + " is not expected to have a cps type") - expr modifyType removeAllCPSAnnotations - } - - // TODO: sanity check that types agree - } - - (stms, expr) - } - - def transInlineValue(tree: Tree, cpsA: CPSInfo)(implicit isAnyParentImpure: Boolean): (List[Tree], Tree, CPSInfo) = { - - val (stms, expr, spc) = transValue(tree, cpsA, None) // never required to be cps - - getAnswerTypeAnn(expr.tpe) match { - case spcVal @ Some(_) => - - val valueTpe = removeAllCPSAnnotations(expr.tpe) - - val sym: Symbol = ( - currentOwner.newValue(newTermName(unit.fresh.newName("tmp")), tree.pos, Flags.SYNTHETIC) - setInfo valueTpe - setAnnotations List(AnnotationInfo(MarkerCPSSym.tpe_*, Nil, Nil)) - ) - expr.changeOwner(currentOwner -> sym) - - (stms ::: List(ValDef(sym, expr) setType(NoType)), - Ident(sym) setType(valueTpe) setPos(tree.pos), linearize(spc, spcVal)(unit, tree.pos)) - - case _ => - (stms, expr, spc) - } - - } - - - - def transInlineStm(stm: Tree, cpsA: CPSInfo)(implicit isAnyParentImpure: Boolean): (List[Tree], CPSInfo) = { - stm match { - - // TODO: what about DefDefs? - // TODO: relation to top-level val def? - // TODO: what about lazy vals? - - case tree @ ValDef(mods, name, tpt, rhs) => - val (stms, anfRhs, spc) = atOwner(tree.symbol) { transValue(rhs, cpsA, None) } - - val tv = new ChangeOwnerTraverser(tree.symbol, currentOwner) - stms.foreach(tv.traverse(_)) - - // TODO: symbol might already have annotation. Should check conformance - // TODO: better yet: do without annotations on symbols - - val spcVal = getAnswerTypeAnn(anfRhs.tpe) - spcVal foreach (_ => tree.symbol setAnnotations List(AnnotationInfo(MarkerCPSSym.tpe_*, Nil, Nil))) - - (stms:::List(treeCopy.ValDef(tree, mods, name, tpt, anfRhs)), linearize(spc, spcVal)(unit, tree.pos)) - - case _ => - val (headStms, headExpr, headSpc) = transInlineValue(stm, cpsA) - val valSpc = getAnswerTypeAnn(headExpr.tpe) - (headStms:::List(headExpr), linearize(headSpc, valSpc)(unit, stm.pos)) - } - } - - // precondition: cpsR.isDefined "implies" isAnyParentImpure - def transBlock(stms: List[Tree], expr: Tree, cpsA: CPSInfo, cpsR: CPSInfo)(implicit isAnyParentImpure: Boolean): (List[Tree], Tree) = { - def rec(currStats: List[Tree], currAns: CPSInfo, accum: List[Tree]): (List[Tree], Tree) = - currStats match { - case Nil => - val (anfStats, anfExpr) = transTailValue(expr, currAns, cpsR) - (accum ++ anfStats, anfExpr) - - case stat :: rest => - val (stats, nextAns) = transInlineStm(stat, currAns) - rec(rest, nextAns, accum ++ stats) - } - - val (anfStats, anfExpr) = rec(stms, cpsA, List()) - // println("\nanf-block:\n"+ ((stms :+ expr) mkString ("{", "\n", "}")) +"\nBECAME\n"+ ((anfStats :+ anfExpr) mkString ("{", "\n", "}"))) - // println("synth case? "+ (anfStats map (t => (t, t.isDef, treeInfo.hasSynthCaseSymbol(t))))) - // SUPER UGLY HACK: handle virtpatmat-style matches, whose labels have already been turned into DefDefs - if (anfStats.nonEmpty && (anfStats forall (t => !t.isDef || treeInfo.hasSynthCaseSymbol(t)))) { - val (prologue, rest) = (anfStats :+ anfExpr) span (s => !s.isInstanceOf[DefDef]) // find first case - // println("rest: "+ rest) - // val (defs, calls) = rest partition (_.isInstanceOf[DefDef]) - if (rest.nonEmpty) { - // the filter drops the ()'s emitted when transValue encountered a LabelDef - val stats = prologue ++ (rest filter (_.isInstanceOf[DefDef])).reverse // ++ calls - // println("REVERSED "+ (stats mkString ("{", "\n", "}"))) - (stats, localTyper.typed{Apply(Ident(rest.head.symbol), List())}) // call first label to kick-start the match - } else (anfStats, anfExpr) - } else (anfStats, anfExpr) - } - } -} diff --git a/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSPlugin.scala b/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSPlugin.scala deleted file mode 100644 index a7e82e949b..0000000000 --- a/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSPlugin.scala +++ /dev/null @@ -1,56 +0,0 @@ -// $Id$ - -package scala.tools.selectivecps - -import scala.tools.nsc -import nsc.Global -import nsc.plugins.Plugin -import nsc.plugins.PluginComponent - -class SelectiveCPSPlugin(val global: Global) extends Plugin { - val name = "continuations" - val description = "applies selective cps conversion" - - val pluginEnabled = options contains "enable" - - val anfPhase = new { - val global = SelectiveCPSPlugin.this.global - val cpsEnabled = pluginEnabled - override val enabled = cpsEnabled - } with SelectiveANFTransform { - val runsAfter = List("pickler") - } - - val cpsPhase = new { - val global = SelectiveCPSPlugin.this.global - val cpsEnabled = pluginEnabled - override val enabled = cpsEnabled - } with SelectiveCPSTransform { - val runsAfter = List("selectiveanf") - override val runsBefore = List("uncurry") - } - - val components = List[PluginComponent](anfPhase, cpsPhase) - - val checker = new { - val global: SelectiveCPSPlugin.this.global.type = SelectiveCPSPlugin.this.global - val cpsEnabled = pluginEnabled - } with CPSAnnotationChecker - - // TODO don't muck up global with unused checkers - global.addAnnotationChecker(checker.checker) - global.analyzer.addAnalyzerPlugin(checker.plugin) - - global.log("instantiated cps plugin: " + this) - - override def init(options: List[String], error: String => Unit) = { - options foreach { - case "enable" => // in initializer - case arg => error(s"Bad argument: $arg") - } - pluginEnabled - } - - override val optionsHelp: Option[String] = - Some(" -P:continuations:enable Enable continuations") -} diff --git a/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala b/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala deleted file mode 100644 index 0210ad3459..0000000000 --- a/src/continuations/plugin/scala/tools/selectivecps/SelectiveCPSTransform.scala +++ /dev/null @@ -1,383 +0,0 @@ -// $Id$ - -package scala.tools.selectivecps - -import scala.tools.nsc.transform._ -import scala.tools.nsc.plugins._ -import scala.tools.nsc.ast._ - -/** - * In methods marked @cps, CPS-transform assignments introduced by ANF-transform phase. - */ -abstract class SelectiveCPSTransform extends PluginComponent with - InfoTransform with TypingTransformers with CPSUtils with TreeDSL { - // inherits abstract value `global` and class `Phase` from Transform - - import global._ // the global environment - import definitions._ // standard classes and methods - import typer.atOwner // methods to type trees - - override def description = "@cps-driven transform of selectiveanf assignments" - - /** the following two members override abstract members in Transform */ - val phaseName: String = "selectivecps" - - protected def newTransformer(unit: CompilationUnit): Transformer = - new CPSTransformer(unit) - - /** This class does not change linearization */ - override def changesBaseClasses = false - - /** - return symbol's transformed type, - */ - def transformInfo(sym: Symbol, tp: Type): Type = { - if (!cpsEnabled) return tp - - val newtp = transformCPSType(tp) - - if (newtp != tp) - debuglog("transformInfo changed type for " + sym + " to " + newtp); - - if (sym == MethReifyR) - debuglog("transformInfo (not)changed type for " + sym + " to " + newtp); - - newtp - } - - def transformCPSType(tp: Type): Type = { // TODO: use a TypeMap? need to handle more cases? - tp match { - case PolyType(params,res) => PolyType(params, transformCPSType(res)) - case NullaryMethodType(res) => NullaryMethodType(transformCPSType(res)) - case MethodType(params,res) => MethodType(params, transformCPSType(res)) - case TypeRef(pre, sym, args) => TypeRef(pre, sym, args.map(transformCPSType(_))) - case _ => - getExternalAnswerTypeAnn(tp) match { - case Some((res, outer)) => - appliedType(Context.tpeHK, List(removeAllCPSAnnotations(tp), res, outer)) - case _ => - removeAllCPSAnnotations(tp) - } - } - } - - - class CPSTransformer(unit: CompilationUnit) extends TypingTransformer(unit) { - private val patmatTransformer = patmat.newTransformer(unit) - - override def transform(tree: Tree): Tree = { - if (!cpsEnabled) return tree - postTransform(mainTransform(tree)) - } - - def postTransform(tree: Tree): Tree = { - tree.setType(transformCPSType(tree.tpe)) - } - - - def mainTransform(tree: Tree): Tree = { - tree match { - - // TODO: can we generalize this? - - case Apply(TypeApply(fun, targs), args) - if (fun.symbol == MethShift) => - debuglog("found shift: " + tree) - atPos(tree.pos) { - val funR = gen.mkAttributedRef(MethShiftR) // TODO: correct? - //gen.mkAttributedSelect(gen.mkAttributedSelect(gen.mkAttributedSelect(gen.mkAttributedIdent(ScalaPackage), - //ScalaPackage.tpe.member("util")), ScalaPackage.tpe.member("util").tpe.member("continuations")), MethShiftR) - //gen.mkAttributedRef(ModCPS.tpe, MethShiftR) // TODO: correct? - debuglog("funR.tpe: " + funR.tpe) - Apply( - TypeApply(funR, targs).setType(appliedType(funR.tpe, targs.map((t:Tree) => t.tpe))), - args.map(transform(_)) - ).setType(transformCPSType(tree.tpe)) - } - - case Apply(TypeApply(fun, targs), args) - if (fun.symbol == MethShiftUnit) => - debuglog("found shiftUnit: " + tree) - atPos(tree.pos) { - val funR = gen.mkAttributedRef(MethShiftUnitR) // TODO: correct? - debuglog("funR.tpe: " + funR.tpe) - Apply( - TypeApply(funR, List(targs(0), targs(1))).setType(appliedType(funR.tpe, - List(targs(0).tpe, targs(1).tpe))), - args.map(transform(_)) - ).setType(appliedType(Context.tpeHK, List(targs(0).tpe,targs(1).tpe,targs(1).tpe))) - } - - case Apply(TypeApply(fun, targs), args) - if (fun.symbol == MethReify) => - log("found reify: " + tree) - atPos(tree.pos) { - val funR = gen.mkAttributedRef(MethReifyR) // TODO: correct? - debuglog("funR.tpe: " + funR.tpe) - Apply( - TypeApply(funR, targs).setType(appliedType(funR.tpe, targs.map((t:Tree) => t.tpe))), - args.map(transform(_)) - ).setType(transformCPSType(tree.tpe)) - } - - case Try(block, catches, finalizer) => - // currently duplicates the catch block into a partial function. - // this is kinda risky, but we don't expect there will be lots - // of try/catches inside catch blocks (exp. blowup unlikely). - - // CAVEAT: finalizers are surprisingly tricky! - // the problem is that they cannot easily be removed - // from the regular control path and hence will - // also be invoked after creating the Context object. - - /* - object Test { - def foo1 = { - throw new Exception("in sub") - shift((k:Int=>Int) => k(1)) - 10 - } - def foo2 = { - shift((k:Int=>Int) => k(2)) - 20 - } - def foo3 = { - shift((k:Int=>Int) => k(3)) - throw new Exception("in sub") - 30 - } - def foo4 = { - shift((k:Int=>Int) => 4) - throw new Exception("in sub") - 40 - } - def bar(x: Int) = try { - if (x == 1) - foo1 - else if (x == 2) - foo2 - else if (x == 3) - foo3 - else //if (x == 4) - foo4 - } catch { - case _ => - println("exception") - 0 - } finally { - println("done") - } - } - - reset(Test.bar(1)) // should print: exception,done,0 - reset(Test.bar(2)) // should print: done,20 <-- but prints: done,done,20 - reset(Test.bar(3)) // should print: exception,done,0 <-- but prints: done,exception,done,0 - reset(Test.bar(4)) // should print: 4 <-- but prints: done,4 - */ - - val block1 = transform(block) - val catches1 = transformCaseDefs(catches) - val finalizer1 = transform(finalizer) - - if (hasAnswerTypeAnn(tree.tpe)) { - //vprintln("CPS Transform: " + tree + "/" + tree.tpe + "/" + block1.tpe) - - val (stms, expr1) = block1 match { - case Block(stms, expr) => (stms, expr) - case expr => (Nil, expr) - } - - val targettp = transformCPSType(tree.tpe) - - val pos = catches.head.pos - val funSym = currentOwner.newValueParameter(cpsNames.catches, pos).setInfo(appliedType(PartialFunctionClass, ThrowableTpe, targettp)) - val funDef = localTyper.typedPos(pos) { - ValDef(funSym, Match(EmptyTree, catches1)) - } - val expr2 = localTyper.typedPos(pos) { - Apply(Select(expr1, expr1.tpe.member(cpsNames.flatMapCatch)), List(Ident(funSym))) - } - - val exSym = currentOwner.newValueParameter(cpsNames.ex, pos).setInfo(ThrowableTpe) - - import CODE._ - // generate a case that is supported directly by the back-end - val catchIfDefined = CaseDef( - Bind(exSym, Ident(nme.WILDCARD)), - EmptyTree, - IF ((REF(funSym) DOT nme.isDefinedAt)(REF(exSym))) THEN (REF(funSym) APPLY (REF(exSym))) ELSE Throw(REF(exSym)) - ) - - val catch2 = localTyper.typedCases(List(catchIfDefined), ThrowableTpe, targettp) - //typedCases(tree, catches, ThrowableTpe, pt) - - patmatTransformer.transform(localTyper.typed(Block(List(funDef), treeCopy.Try(tree, treeCopy.Block(block1, stms, expr2), catch2, finalizer1)))) - - -/* - disabled for now - see notes above - - val expr3 = if (!finalizer.isEmpty) { - val pos = finalizer.pos - val finalizer2 = duplicateTree(finalizer1) - val fun = Function(List(), finalizer2) - val expr3 = localTyper.typedPos(pos) { Apply(Select(expr2, expr2.tpe.member("mapFinally")), List(fun)) } - - val chown = new ChangeOwnerTraverser(currentOwner, fun.symbol) - chown.traverse(finalizer2) - - expr3 - } else - expr2 -*/ - } else { - treeCopy.Try(tree, block1, catches1, finalizer1) - } - - case Block(stms, expr) => - - val (stms1, expr1) = transBlock(stms, expr) - treeCopy.Block(tree, stms1, expr1) - - case _ => - super.transform(tree) - } - } - - - - def transBlock(stms: List[Tree], expr: Tree): (List[Tree], Tree) = { - - stms match { - case Nil => - (Nil, transform(expr)) - - case stm::rest => - - stm match { - case vd @ ValDef(mods, name, tpt, rhs) - if (vd.symbol.hasAnnotation(MarkerCPSSym)) => - - debuglog("found marked ValDef "+name+" of type " + vd.symbol.tpe) - - val tpe = vd.symbol.tpe - val rhs1 = atOwner(vd.symbol) { transform(rhs) } - rhs1.changeOwner(vd.symbol -> currentOwner) // TODO: don't traverse twice - - debuglog("valdef symbol " + vd.symbol + " has type " + tpe) - debuglog("right hand side " + rhs1 + " has type " + rhs1.tpe) - - debuglog("currentOwner: " + currentOwner) - debuglog("currentMethod: " + currentMethod) - - val (bodyStms, bodyExpr) = transBlock(rest, expr) - // FIXME: result will later be traversed again by TreeSymSubstituter and - // ChangeOwnerTraverser => exp. running time. - // Should be changed to fuse traversals into one. - - val specialCaseTrivial = bodyExpr match { - case Apply(fun, args) => - // for now, look for explicit tail calls only. - // are there other cases that could profit from specializing on - // trivial contexts as well? - (bodyExpr.tpe.typeSymbol == Context) && (currentMethod == fun.symbol) - case _ => false - } - - def applyTrivial(ctxValSym: Symbol, body: Tree) = { - - val body1 = (new TreeSymSubstituter(List(vd.symbol), List(ctxValSym)))(body) - - val body2 = localTyper.typedPos(vd.symbol.pos) { body1 } - - // in theory it would be nicer to look for an @cps annotation instead - // of testing for Context - if ((body2.tpe == null) || !(body2.tpe.typeSymbol == Context)) { - //println(body2 + "/" + body2.tpe) - unit.error(rhs.pos, "cannot compute type for CPS-transformed function result") - } - body2 - } - - def applyCombinatorFun(ctxR: Tree, body: Tree) = { - val arg = currentOwner.newValueParameter(name, ctxR.pos).setInfo(tpe) - val body1 = (new TreeSymSubstituter(List(vd.symbol), List(arg)))(body) - val fun = localTyper.typedPos(vd.symbol.pos) { Function(List(ValDef(arg)), body1) } // types body as well - arg.owner = fun.symbol - body1.changeOwner(currentOwner -> fun.symbol) - - // see note about multiple traversals above - - debuglog("fun.symbol: "+fun.symbol) - debuglog("fun.symbol.owner: "+fun.symbol.owner) - debuglog("arg.owner: "+arg.owner) - - debuglog("fun.tpe:"+fun.tpe) - debuglog("return type of fun:"+body1.tpe) - - var methodName = nme.map - - if (body1.tpe != null) { - if (body1.tpe.typeSymbol == Context) - methodName = nme.flatMap - } - else - unit.error(rhs.pos, "cannot compute type for CPS-transformed function result") - - debuglog("will use method:"+methodName) - - localTyper.typedPos(vd.symbol.pos) { - Apply(Select(ctxR, ctxR.tpe.member(methodName)), List(fun)) - } - } - - // TODO use gen.mkBlock after 2.11.0-M6. Why wait? It allows us to still build in development - // mode with `ant -DskipLocker=1` - def mkBlock(stms: List[Tree], expr: Tree) = if (stms.nonEmpty) Block(stms, expr) else expr - - try { - if (specialCaseTrivial) { - debuglog("will optimize possible tail call: " + bodyExpr) - - // FIXME: flatMap impl has become more complicated due to - // exceptions. do we need to put a try/catch in the then part?? - - // val ctx = <rhs> - // if (ctx.isTrivial) - // val <lhs> = ctx.getTrivialValue; ... <--- TODO: try/catch ??? don't bother for the moment... - // else - // ctx.flatMap { <lhs> => ... } - val ctxSym = currentOwner.newValue(newTermName("" + vd.symbol.name + cpsNames.shiftSuffix)).setInfo(rhs1.tpe) - val ctxDef = localTyper.typed(ValDef(ctxSym, rhs1)) - def ctxRef = localTyper.typed(Ident(ctxSym)) - val argSym = currentOwner.newValue(vd.symbol.name.toTermName).setInfo(tpe) - val argDef = localTyper.typed(ValDef(argSym, Select(ctxRef, ctxRef.tpe.member(cpsNames.getTrivialValue)))) - val switchExpr = localTyper.typedPos(vd.symbol.pos) { - val body2 = mkBlock(bodyStms, bodyExpr).duplicate // dup before typing! - If(Select(ctxRef, ctxSym.tpe.member(cpsNames.isTrivial)), - applyTrivial(argSym, mkBlock(argDef::bodyStms, bodyExpr)), - applyCombinatorFun(ctxRef, body2)) - } - (List(ctxDef), switchExpr) - } else { - // ctx.flatMap { <lhs> => ... } - // or - // ctx.map { <lhs> => ... } - (Nil, applyCombinatorFun(rhs1, mkBlock(bodyStms, bodyExpr))) - } - } catch { - case ex:TypeError => - unit.error(ex.pos, ex.msg) - (bodyStms, bodyExpr) - } - - case _ => - val stm1 = transform(stm) - val (a, b) = transBlock(rest, expr) - (stm1::a, b) - } - } - } - - - } -} diff --git a/src/continuations/plugin/scalac-plugin.xml b/src/continuations/plugin/scalac-plugin.xml deleted file mode 100644 index 04d42655c5..0000000000 --- a/src/continuations/plugin/scalac-plugin.xml +++ /dev/null @@ -1,5 +0,0 @@ -<!-- $Id$ --> -<plugin> - <name>continuations</name> - <classname>scala.tools.selectivecps.SelectiveCPSPlugin</classname> -</plugin> |