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author | Dmitry Petrashko <dark@d-d.me> | 2017-01-11 19:14:53 +0100 |
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committer | GitHub <noreply@github.com> | 2017-01-11 19:14:53 +0100 |
commit | ba7e12999dc645dbcba04cf365dfd4d621ee4662 (patch) | |
tree | 87001ce07a6013719df241cc0f28c12ba5ec6718 /compiler | |
parent | 8b44b6c1fb0f03a555834d189b98ef30091153fe (diff) | |
parent | cf57534c6141593fbe2ac2fec9d101fa662ecf05 (diff) | |
download | dotty-ba7e12999dc645dbcba04cf365dfd4d621ee4662.tar.gz dotty-ba7e12999dc645dbcba04cf365dfd4d621ee4662.tar.bz2 dotty-ba7e12999dc645dbcba04cf365dfd4d621ee4662.zip |
Merge pull request #1883 from dotty-staging/fix-1877
Fix #1877: Add forwarders for primitive/generic mixins.
Diffstat (limited to 'compiler')
4 files changed, 84 insertions, 6 deletions
diff --git a/compiler/src/dotty/tools/dotc/Compiler.scala b/compiler/src/dotty/tools/dotc/Compiler.scala index 900d2b0e3..1d319242b 100644 --- a/compiler/src/dotty/tools/dotc/Compiler.scala +++ b/compiler/src/dotty/tools/dotc/Compiler.scala @@ -72,6 +72,7 @@ class Compiler { new ElimByName, // Expand by-name parameters and arguments new AugmentScala2Traits, // Expand traits defined in Scala 2.11 to simulate old-style rewritings new ResolveSuper, // Implement super accessors and add forwarders to trait methods + new PrimitiveForwarders, // Add forwarders to trait methods that have a mismatch between generic and primitives new ArrayConstructors), // Intercept creation of (non-generic) arrays and intrinsify. List(new Erasure), // Rewrite types to JVM model, erasing all type parameters, abstract types and refinements. List(new ElimErasedValueType, // Expand erased value types to their underlying implmementation types diff --git a/compiler/src/dotty/tools/dotc/transform/MixinOps.scala b/compiler/src/dotty/tools/dotc/transform/MixinOps.scala index 6cebf7197..25aa9ffaf 100644 --- a/compiler/src/dotty/tools/dotc/transform/MixinOps.scala +++ b/compiler/src/dotty/tools/dotc/transform/MixinOps.scala @@ -48,11 +48,7 @@ class MixinOps(cls: ClassSymbol, thisTransform: DenotTransformer)(implicit ctx: * - there are multiple traits defining method with same signature */ def needsForwarder(meth: Symbol): Boolean = { - lazy val competingMethods = cls.baseClasses.iterator - .filter(_ ne meth.owner) - .map(meth.overriddenSymbol) - .filter(_.exists) - .toList + lazy val competingMethods = competingMethodsIterator(meth).toList def needsDisambiguation = competingMethods.exists(x=> !(x is Deferred)) // multiple implementations are available def hasNonInterfaceDefinition = competingMethods.exists(!_.owner.is(Trait)) // there is a definition originating from class @@ -61,8 +57,38 @@ class MixinOps(cls: ClassSymbol, thisTransform: DenotTransformer)(implicit ctx: (needsDisambiguation || hasNonInterfaceDefinition || meth.owner.is(Scala2x)) } + /** Get `sym` of the method that needs a forwarder + * Method needs a forwarder in those cases: + * - there is a trait that defines a primitive version of implemented polymorphic method. + * - there is a trait that defines a polymorphic version of implemented primitive method. + */ + def needsPrimitiveForwarderTo(meth: Symbol): Option[Symbol] = { + def hasPrimitiveMissMatch(tp1: Type, tp2: Type): Boolean = (tp1, tp2) match { + case (tp1: MethodicType, tp2: MethodicType) => + hasPrimitiveMissMatch(tp1.resultType, tp2.resultType) || + tp1.paramTypess.flatten.zip(tp1.paramTypess.flatten).exists(args => hasPrimitiveMissMatch(args._1, args._2)) + case _ => + def isPrimitiveOrValueClass(sym: Symbol): Boolean = sym.isPrimitiveValueClass || sym.isValueClass + isPrimitiveOrValueClass(tp1.typeSymbol) ^ isPrimitiveOrValueClass(tp2.typeSymbol) + } + + def needsPrimitiveForwarder(m: Symbol): Boolean = + m.owner != cls && !m.is(Deferred) && hasPrimitiveMissMatch(meth.info, m.info) + + if (!meth.is(Method | Deferred, butNot = PrivateOrAccessor) || meth.overriddenSymbol(cls).exists || needsForwarder(meth)) None + else competingMethodsIterator(meth).find(needsPrimitiveForwarder) + } + + final val PrivateOrAccessor = Private | Accessor final val PrivateOrAccessorOrDeferred = Private | Accessor | Deferred def forwarder(target: Symbol) = (targs: List[Type]) => (vrefss: List[List[Tree]]) => superRef(target).appliedToTypes(targs).appliedToArgss(vrefss) + + private def competingMethodsIterator(meth: Symbol): Iterator[Symbol] = { + cls.baseClasses.iterator + .filter(_ ne meth.owner) + .map(meth.overriddenSymbol) + .filter(_.exists) + } } diff --git a/compiler/src/dotty/tools/dotc/transform/PrimitiveForwarders.scala b/compiler/src/dotty/tools/dotc/transform/PrimitiveForwarders.scala new file mode 100644 index 000000000..d752ce8e7 --- /dev/null +++ b/compiler/src/dotty/tools/dotc/transform/PrimitiveForwarders.scala @@ -0,0 +1,51 @@ +package dotty.tools.dotc +package transform + +import core._ +import TreeTransforms._ +import Contexts.Context +import Flags._ +import SymUtils._ +import Symbols._ +import SymDenotations._ +import Types._ +import Decorators._ +import DenotTransformers._ +import StdNames._ +import NameOps._ +import ast.Trees._ +import util.Positions._ +import Names._ +import collection.mutable +import ResolveSuper._ + +/** This phase adds forwarder where mixedin generic and primitive typed methods have a missmatch. + * In particular for every method that is declared both as generic with a primitive type and with a primitive type + * `<mods> def f[Ts](ps1)...(psN): U` in trait M` and + * `<mods> def f[Ts](ps1)...(psN): V = ...` in implemented in N` + * where U is a primitive and V a polymorphic type (or vice versa) needs: + * + * <mods> def f[Ts](ps1)...(psN): U = super[N].f[Ts](ps1)...(psN) + * + * IMPORTANT: When\If Valhalla happens, we'll need to move mixin before erasure and than this code will need to be rewritten + * as it will instead change super-class. + */ +class PrimitiveForwarders extends MiniPhaseTransform with IdentityDenotTransformer { thisTransform => + import ast.tpd._ + + override def phaseName: String = "primitiveForwarders" + + override def runsAfter = Set(classOf[ResolveSuper]) + + override def transformTemplate(impl: Template)(implicit ctx: Context, info: TransformerInfo) = { + val cls = impl.symbol.owner.asClass + val ops = new MixinOps(cls, thisTransform) + import ops._ + + def methodPrimitiveForwarders: List[Tree] = + for (meth <- mixins.flatMap(_.info.decls.flatMap(needsPrimitiveForwarderTo)).distinct) + yield polyDefDef(implementation(meth.asTerm), forwarder(meth)) + + cpy.Template(impl)(body = methodPrimitiveForwarders ::: impl.body) + } +} diff --git a/compiler/src/dotty/tools/dotc/transform/ResolveSuper.scala b/compiler/src/dotty/tools/dotc/transform/ResolveSuper.scala index e718a7e60..3a301167d 100644 --- a/compiler/src/dotty/tools/dotc/transform/ResolveSuper.scala +++ b/compiler/src/dotty/tools/dotc/transform/ResolveSuper.scala @@ -85,7 +85,7 @@ class ResolveSuper extends MiniPhaseTransform with IdentityDenotTransformer { th private val PrivateOrAccessorOrDeferred = Private | Accessor | Deferred } -object ResolveSuper{ +object ResolveSuper { /** Returns the symbol that is accessed by a super-accessor in a mixin composition. * * @param base The class in which everything is mixed together |