diff options
Diffstat (limited to 'src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala')
-rw-r--r-- | src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala | 61 |
1 files changed, 49 insertions, 12 deletions
diff --git a/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala b/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala index c4599bebbc..5f3cb22c44 100644 --- a/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala +++ b/src/continuations/plugin/scala/tools/selectivecps/CPSAnnotationChecker.scala @@ -154,10 +154,8 @@ abstract class CPSAnnotationChecker extends CPSUtils with Modes { if ((mode & global.analyzer.EXPRmode) != 0) { if ((annots1 corresponds annots2)(_.atp <:< _.atp)) { vprintln("already same, can't adapt further") - return false - } - - if (annots1.isEmpty && !annots2.isEmpty && ((mode & global.analyzer.BYVALmode) == 0)) { + false + } else if (annots1.isEmpty && !annots2.isEmpty && ((mode & global.analyzer.BYVALmode) == 0)) { //println("can adapt annotations? " + tree + " / " + tree.tpe + " / " + Integer.toHexString(mode) + " / " + pt) if (!hasPlusMarker(tree.tpe)) { // val base = tree.tpe <:< removeAllCPSAnnotations(pt) @@ -167,17 +165,26 @@ abstract class CPSAnnotationChecker extends CPSUtils with Modes { // TBD: use same or not? //if (same) { vprintln("yes we can!! (unit)") - return true + true //} - } - } else if (!annots1.isEmpty && ((mode & global.analyzer.BYVALmode) != 0)) { - if (!hasMinusMarker(tree.tpe)) { + } else false + } else if (!hasPlusMarker(tree.tpe) && annots1.isEmpty && !annots2.isEmpty && ((mode & global.analyzer.RETmode) != 0)) { + vprintln("checking enclosing method's result type without annotations") + tree.tpe <:< pt.withoutAnnotations + } else if (!hasMinusMarker(tree.tpe) && !annots1.isEmpty && ((mode & global.analyzer.BYVALmode) != 0)) { + 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)") - return true + 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 } - } - } - false + } else false + } else false } override def adaptAnnotations(tree: Tree, mode: Int, pt: Type): Tree = { @@ -188,6 +195,7 @@ abstract class CPSAnnotationChecker extends CPSUtils with Modes { val patMode = (mode & global.analyzer.PATTERNmode) != 0 val exprMode = (mode & global.analyzer.EXPRmode) != 0 val byValMode = (mode & global.analyzer.BYVALmode) != 0 + val retMode = (mode & global.analyzer.RETmode) != 0 val annotsTree = cpsParamAnnotation(tree.tpe) val annotsExpected = cpsParamAnnotation(pt) @@ -214,9 +222,38 @@ abstract class CPSAnnotationChecker extends CPSUtils with Modes { val res = tree modifyType addMinusMarker vprintln("adapted annotations (by val) of " + tree + " to " + res.tpe) res + } else if (retMode && !hasPlusMarker(tree.tpe) && annotsTree.isEmpty && annotsExpected.nonEmpty) { + // 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 (_ withAnnotations List(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 `NothingClass.tpe`). + * + * 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 adaptTypeOfReturn(tree: Tree, pt: Type, default: => Type): Type = { + // only adapt if method's result type (pt) is cps type + val annots = cpsParamAnnotation(pt) + if (annots.nonEmpty) { + // return type of `tree` without plus marker, but only if it doesn't have other cps annots + if (hasPlusMarker(tree.tpe) && !hasCpsParamTypes(tree.tpe)) + tree.setType(removeAttribs(tree.tpe, MarkerCPSAdaptPlus)) + tree.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 |