diff options
Diffstat (limited to 'src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala')
| -rw-r--r-- | src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala | 261 |
1 files changed, 173 insertions, 88 deletions
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala b/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala index 45d9cc3ff3..d10b6c8dba 100644 --- a/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala +++ b/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala @@ -7,8 +7,9 @@ package scala.tools.nsc package backend.jvm import scala.tools.asm +import scala.tools.nsc.backend.jvm.analysis.BackendUtils import scala.tools.nsc.backend.jvm.opt._ -import scala.tools.nsc.backend.jvm.BTypes.{InlineInfo, MethodInlineInfo, InternalName} +import scala.tools.nsc.backend.jvm.BTypes._ import BackendReporting._ import scala.tools.nsc.settings.ScalaSettings @@ -27,21 +28,22 @@ import scala.tools.nsc.settings.ScalaSettings class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { import global._ import definitions._ + import genBCode._ - val bCodeICodeCommon: BCodeICodeCommon[global.type] = new BCodeICodeCommon(global) - val bCodeAsmCommon: BCodeAsmCommon[global.type] = new BCodeAsmCommon(global) - import bCodeAsmCommon._ + val backendUtils: BackendUtils[this.type] = new BackendUtils(this) // Why the proxy, see documentation of class [[CoreBTypes]]. val coreBTypes = new CoreBTypesProxy[this.type](this) import coreBTypes._ - val byteCodeRepository = new ByteCodeRepository(global.classPath, javaDefinedClasses, recordPerRunCache(collection.concurrent.TrieMap.empty)) + val byteCodeRepository: ByteCodeRepository[this.type] = new ByteCodeRepository(global.classPath, this) val localOpt: LocalOpt[this.type] = new LocalOpt(this) val inliner: Inliner[this.type] = new Inliner(this) + val inlinerHeuristics: InlinerHeuristics[this.type] = new InlinerHeuristics(this) + val closureOptimizer: ClosureOptimizer[this.type] = new ClosureOptimizer(this) val callGraph: CallGraph[this.type] = new CallGraph(this) @@ -94,19 +96,14 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { * scala.Null is mapped to scala.runtime.Null$. This is because there exist no class files * for the Nothing / Null. If used for example as a parameter type, we use the runtime classes * in the classfile method signature. - * - * Note that the referenced class symbol may be an implementation class. For example when - * compiling a mixed-in method that forwards to the static method in the implementation class, - * the class descriptor of the receiver (the implementation class) is obtained by creating the - * ClassBType. */ final def classBTypeFromSymbol(classSym: Symbol): ClassBType = { assert(classSym != NoSymbol, "Cannot create ClassBType from NoSymbol") assert(classSym.isClass, s"Cannot create ClassBType from non-class symbol $classSym") assertClassNotArrayNotPrimitive(classSym) - assert(!primitiveTypeMap.contains(classSym) || isCompilingPrimitive, s"Cannot create ClassBType for primitive class symbol $classSym") - if (classSym == NothingClass) RT_NOTHING - else if (classSym == NullClass) RT_NULL + assert(!primitiveTypeToBType.contains(classSym) || isCompilingPrimitive, s"Cannot create ClassBType for primitive class symbol $classSym") + if (classSym == NothingClass) srNothingRef + else if (classSym == NullClass) srNullRef else { val internalName = classSym.javaBinaryName.toString classBTypeFromInternalName.getOrElse(internalName, { @@ -128,17 +125,35 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { */ final def methodBTypeFromSymbol(methodSymbol: Symbol): MethodBType = { assert(methodSymbol.isMethod, s"not a method-symbol: $methodSymbol") + methodBTypeFromMethodType(methodSymbol.info, methodSymbol.isClassConstructor || methodSymbol.isConstructor) + } + + /** + * Builds a [[MethodBType]] for a method type. + */ + final def methodBTypeFromMethodType(tpe: Type, isConstructor: Boolean): MethodBType = { val resultType: BType = - if (methodSymbol.isClassConstructor || methodSymbol.isConstructor) UNIT - else typeToBType(methodSymbol.tpe.resultType) - MethodBType(methodSymbol.tpe.paramTypes map typeToBType, resultType) + if (isConstructor) UNIT + else typeToBType(tpe.resultType) + MethodBType(tpe.paramTypes map typeToBType, resultType) + } + + def bootstrapMethodArg(t: Constant, pos: Position): AnyRef = t match { + case Constant(mt: Type) => methodBTypeFromMethodType(transformedType(mt), isConstructor = false).toASMType + case c @ Constant(sym: Symbol) => staticHandleFromSymbol(sym) + case c @ Constant(value: String) => value + case c @ Constant(value) if c.isNonUnitAnyVal => c.value.asInstanceOf[AnyRef] + case _ => reporter.error(pos, "Unable to convert static argument of ApplyDynamic into a classfile constant: " + t); null + } + + def staticHandleFromSymbol(sym: Symbol): asm.Handle = { + val owner = if (sym.owner.isModuleClass) sym.owner.linkedClassOfClass else sym.owner + val descriptor = methodBTypeFromMethodType(sym.info, isConstructor = false).descriptor + new asm.Handle(asm.Opcodes.H_INVOKESTATIC, classBTypeFromSymbol(owner).internalName, sym.name.encoded, descriptor) } /** * This method returns the BType for a type reference, for example a parameter type. - * - * If `t` references a class, typeToBType ensures that the class is not an implementation class. - * See also comment on classBTypeFromSymbol, which is invoked for implementation classes. */ final def typeToBType(t: Type): BType = { import definitions.ArrayClass @@ -149,17 +164,16 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { */ def primitiveOrClassToBType(sym: Symbol): BType = { assertClassNotArray(sym) - assert(!sym.isImplClass, sym) - primitiveTypeMap.getOrElse(sym, classBTypeFromSymbol(sym)) + primitiveTypeToBType.getOrElse(sym, classBTypeFromSymbol(sym)) } /** * When compiling Array.scala, the type parameter T is not erased and shows up in method - * signatures, e.g. `def apply(i: Int): T`. A TyperRef to T is replaced by ObjectReference. + * signatures, e.g. `def apply(i: Int): T`. A TypeRef for T is replaced by ObjectRef. */ def nonClassTypeRefToBType(sym: Symbol): ClassBType = { assert(sym.isType && isCompilingArray, sym) - ObjectReference + ObjectRef } t.dealiasWiden match { @@ -168,39 +182,24 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { case TypeRef(_, sym, _) => primitiveOrClassToBType(sym) // Common reference to a type such as scala.Int or java.lang.String case ClassInfoType(_, _, sym) => primitiveOrClassToBType(sym) // We get here, for example, for genLoadModule, which invokes typeToBType(moduleClassSymbol.info) - /* AnnotatedType should (probably) be eliminated by erasure. However we know it happens for - * meta-annotated annotations (@(ann @getter) val x = 0), so we don't emit a warning. - * The type in the AnnotationInfo is an AnnotatedTpe. Tested in jvm/annotations.scala. - */ - case a @ AnnotatedType(_, t) => - debuglog(s"typeKind of annotated type $a") - typeToBType(t) - - /* ExistentialType should (probably) be eliminated by erasure. We know they get here for - * classOf constants: - * class C[T] - * class T { final val k = classOf[C[_]] } - */ - case e @ ExistentialType(_, t) => - debuglog(s"typeKind of existential type $e") - typeToBType(t) - /* The cases below should probably never occur. They are kept for now to avoid introducing * new compiler crashes, but we added a warning. The compiler / library bootstrap and the * test suite don't produce any warning. */ case tp => - currentUnit.warning(tp.typeSymbol.pos, + warning(tp.typeSymbol.pos, s"an unexpected type representation reached the compiler backend while compiling $currentUnit: $tp. " + "If possible, please file a bug on issues.scala-lang.org.") tp match { - case ThisType(ArrayClass) => ObjectReference // was introduced in 9b17332f11 to fix SI-999, but this code is not reached in its test, or any other test - case ThisType(sym) => classBTypeFromSymbol(sym) - case SingleType(_, sym) => primitiveOrClassToBType(sym) - case ConstantType(_) => typeToBType(t.underlying) - case RefinedType(parents, _) => parents.map(typeToBType(_).asClassBType).reduceLeft((a, b) => a.jvmWiseLUB(b).get) + case ThisType(ArrayClass) => ObjectRef // was introduced in 9b17332f11 to fix SI-999, but this code is not reached in its test, or any other test + case ThisType(sym) => classBTypeFromSymbol(sym) + case SingleType(_, sym) => primitiveOrClassToBType(sym) + case ConstantType(_) => typeToBType(t.underlying) + case RefinedType(parents, _) => parents.map(typeToBType(_).asClassBType).reduceLeft((a, b) => a.jvmWiseLUB(b).get) + case AnnotatedType(_, t) => typeToBType(t) + case ExistentialType(_, t) => typeToBType(t) } } } @@ -212,15 +211,108 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { def assertClassNotArrayNotPrimitive(sym: Symbol): Unit = { assertClassNotArray(sym) - assert(!primitiveTypeMap.contains(sym) || isCompilingPrimitive, sym) + assert(!primitiveTypeToBType.contains(sym) || isCompilingPrimitive, sym) + } + + def implementedInterfaces(classSym: Symbol): List[Symbol] = { + // Additional interface parents based on annotations and other cues + def newParentForAnnotation(ann: AnnotationInfo): Option[Type] = ann.symbol match { + case RemoteAttr => Some(RemoteInterfaceClass.tpe) + case _ => None + } + + // SI-9393: java annotations are interfaces, but the classfile / java source parsers make them look like classes. + def isInterfaceOrTrait(sym: Symbol) = sym.isInterface || sym.isTrait || sym.hasJavaAnnotationFlag + + val classParents = { + val parents = classSym.info.parents + // SI-9393: the classfile / java source parsers add Annotation and ClassfileAnnotation to the + // parents of a java annotations. undo this for the backend (where we need classfile-level information). + if (classSym.hasJavaAnnotationFlag) parents.filterNot(c => c.typeSymbol == ClassfileAnnotationClass || c.typeSymbol == AnnotationClass) + else parents + } + + val allParents = classParents ++ classSym.annotations.flatMap(newParentForAnnotation) + + // We keep the superClass when computing minimizeParents to eliminate more interfaces. + // Example: T can be eliminated from D + // trait T + // class C extends T + // class D extends C with T + val interfaces = erasure.minimizeParents(allParents) match { + case superClass :: ifs if !isInterfaceOrTrait(superClass.typeSymbol) => + ifs + case ifs => + // minimizeParents removes the superclass if it's redundant, for example: + // trait A + // class C extends Object with A // minimizeParents removes Object + ifs + } + interfaces.map(_.typeSymbol) } + /** + * The member classes of a class symbol. Note that the result of this method depends on the + * current phase, for example, after lambdalift, all local classes become member of the enclosing + * class. + * + * Specialized classes are always considered top-level, see comment in BTypes. + */ + private def memberClassesForInnerClassTable(classSymbol: Symbol): List[Symbol] = classSymbol.info.decls.collect({ + case sym if sym.isClass && !considerAsTopLevelImplementationArtifact(sym) => + sym + case sym if sym.isModule && !considerAsTopLevelImplementationArtifact(sym) => + val r = exitingPickler(sym.moduleClass) + assert(r != NoSymbol, sym.fullLocationString) + r + })(collection.breakOut) + private def setClassInfo(classSym: Symbol, classBType: ClassBType): ClassBType = { - // Check for isImplClass: trait implementation classes have NoSymbol as superClass + /** + * Reconstruct the classfile flags from a Java defined class symbol. + * + * The implementation of this method is slightly different from `javaFlags` in BTypesFromSymbols. + * The javaFlags method is primarily used to map Scala symbol flags to sensible classfile flags + * that are used in the generated classfiles. For example, all classes emitted by the Scala + * compiler have ACC_PUBLIC. + * + * When building a [[ClassBType]] from a Java class symbol, the flags in the type's `info` have + * to correspond exactly to the flags in the classfile. For example, if the class is package + * protected (i.e., it doesn't have the ACC_PUBLIC flag), this needs to be reflected in the + * ClassBType. For example, the inliner needs the correct flags for access checks. + * + * Class flags are listed here: + * https://docs.oracle.com/javase/specs/jvms/se7/html/jvms-4.html#jvms-4.1-200-E.1 + */ + def javaClassfileFlags(classSym: Symbol): Int = { + assert(classSym.isJava, s"Expected Java class symbol, got ${classSym.fullName}") + import asm.Opcodes._ + def enumFlags = ACC_ENUM | { + // Java enums have the `ACC_ABSTRACT` flag if they have a deferred method. + // We cannot trust `hasAbstractFlag`: the ClassfileParser adds `ABSTRACT` and `SEALED` to all + // Java enums for exhaustiveness checking. + val hasAbstractMethod = classSym.info.decls.exists(s => s.isMethod && s.isDeferred) + if (hasAbstractMethod) ACC_ABSTRACT else 0 + } + GenBCode.mkFlags( + // SI-9393: the classfile / java source parser make java annotation symbols look like classes. + // here we recover the actual classfile flags. + if (classSym.hasJavaAnnotationFlag) ACC_ANNOTATION | ACC_INTERFACE | ACC_ABSTRACT else 0, + if (classSym.isPublic) ACC_PUBLIC else 0, + if (classSym.isFinal) ACC_FINAL else 0, + // see the link above. javac does the same: ACC_SUPER for all classes, but not interfaces. + if (classSym.isInterface) ACC_INTERFACE else ACC_SUPER, + // for Java enums, we cannot trust `hasAbstractFlag` (see comment in enumFlags) + if (!classSym.hasJavaEnumFlag && classSym.hasAbstractFlag) ACC_ABSTRACT else 0, + if (classSym.isArtifact) ACC_SYNTHETIC else 0, + if (classSym.hasJavaEnumFlag) enumFlags else 0 + ) + } + // Check for hasAnnotationFlag for SI-9393: the classfile / java source parsers add // scala.annotation.Annotation as superclass to java annotations. In reality, java // annotation classfiles have superclass Object (like any interface classfile). - val superClassSym = if (classSym.isImplClass || classSym.hasJavaAnnotationFlag) ObjectClass else { + val superClassSym = if (classSym.hasJavaAnnotationFlag) ObjectClass else { val sc = classSym.superClass // SI-9393: Java annotation classes don't have the ABSTRACT/INTERFACE flag, so they appear // (wrongly) as superclasses. Fix this for BTypes: the java annotation will appear as interface @@ -235,7 +327,7 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { superClassSym == ObjectClass else // A ClassBType for a primitive class (scala.Boolean et al) is only created when compiling these classes. - ((superClassSym != NoSymbol) && !superClassSym.isInterface) || (isCompilingPrimitive && primitiveTypeMap.contains(classSym)), + ((superClassSym != NoSymbol) && !superClassSym.isInterface) || (isCompilingPrimitive && primitiveTypeToBType.contains(classSym)), s"Bad superClass for $classSym: $superClassSym" ) val superClass = if (superClassSym == NoSymbol) None @@ -251,13 +343,6 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { /* The InnerClass table of a class C must contain all nested classes of C, even if they are only * declared but not otherwise referenced in C (from the bytecode or a method / field signature). * We collect them here. - * - * Nested classes that are also referenced in C will be added to the innerClassBufferASM during - * code generation, but those duplicates will be eliminated when emitting the InnerClass - * attribute. - * - * Why do we need to collect classes into innerClassBufferASM at all? To collect references to - * nested classes, but NOT nested in C, that are used within C. */ val nestedClassSymbols = { val linkedClass = exitingPickler(classSym.linkedClassOfClass) // linkedCoC does not work properly in late phases @@ -286,8 +371,8 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { } val companionModuleMembers = if (considerAsTopLevelImplementationArtifact(classSym)) Nil else { - // If this is a top-level non-impl (*) class, the member classes of the companion object are - // added as members of the class. For example: + // If this is a top-level class, the member classes of the companion object are added as + // members of the class. For example: // class C { } // object C { // class D @@ -298,11 +383,6 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { // (done by buildNestedInfo). See comment in BTypes. // For consistency, the InnerClass entry for D needs to be present in C - to Java it looks // like D is a member of C, not C$. - // - // (*) We exclude impl classes: if the classfile for the impl class exists on the classpath, - // a linkedClass symbol is found for which isTopLevelModule is true, so we end up searching - // members of that weird impl-class-module-class-symbol. that search probably cannot return - // any classes, but it's better to exclude it. val javaCompatMembers = { if (linkedClass != NoSymbol && isTopLevelModuleClass(linkedClass)) // phase travel to exitingPickler: this makes sure that memberClassesForInnerClassTable only sees member @@ -360,7 +440,7 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { assert(innerClassSym.isClass, s"Cannot build NestedInfo for non-class symbol $innerClassSym") val isTopLevel = innerClassSym.rawowner.isPackageClass - // impl classes are considered top-level, see comment in BTypes + // specialized classes are considered top-level, see comment in BTypes if (isTopLevel || considerAsTopLevelImplementationArtifact(innerClassSym)) None else if (innerClassSym.rawowner.isTerm) { // This case should never be reached: the lambdalift phase mutates the rawowner field of all @@ -444,13 +524,13 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { case Right(classNode) => inlineInfoFromClassfile(classNode) case Left(missingClass) => - InlineInfo(None, false, Map.empty, Some(ClassNotFoundWhenBuildingInlineInfoFromSymbol(missingClass))) + EmptyInlineInfo.copy(warning = Some(ClassNotFoundWhenBuildingInlineInfoFromSymbol(missingClass))) } } } /** - * For top-level objects without a companion class, the compilere generates a mirror class with + * For top-level objects without a companion class, the compiler generates a mirror class with * static forwarders (Java compat). There's no symbol for the mirror class, but we still need a * ClassBType (its info.nestedClasses will hold the InnerClass entries, see comment in BTypes). */ @@ -462,12 +542,27 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { // class info consistent with BCodeHelpers.genMirrorClass val nested = exitingPickler(memberClassesForInnerClassTable(moduleClassSym)) map classBTypeFromSymbol c.info = Right(ClassInfo( - superClass = Some(ObjectReference), + superClass = Some(ObjectRef), interfaces = Nil, flags = asm.Opcodes.ACC_SUPER | asm.Opcodes.ACC_PUBLIC | asm.Opcodes.ACC_FINAL, nestedClasses = nested, nestedInfo = None, - InlineInfo(None, true, Map.empty, None))) // no InlineInfo needed, scala never invokes methods on the mirror class + inlineInfo = EmptyInlineInfo.copy(isEffectivelyFinal = true))) // no method inline infos needed, scala never invokes methods on the mirror class + c + }) + } + + def beanInfoClassClassBType(mainClass: Symbol): ClassBType = { + val internalName = mainClass.javaBinaryName.toString + "BeanInfo" + classBTypeFromInternalName.getOrElse(internalName, { + val c = ClassBType(internalName) + c.info = Right(ClassInfo( + superClass = Some(sbScalaBeanInfoRef), + interfaces = Nil, + flags = javaFlags(mainClass), + nestedClasses = Nil, + nestedInfo = None, + inlineInfo = EmptyInlineInfo)) c }) } @@ -478,26 +573,16 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { */ final def isTopLevelModuleClass(sym: Symbol): Boolean = exitingPickler { // phase travel to pickler required for isNestedClass (looks at owner) - val r = sym.isModuleClass && !sym.isNestedClass - // The mixin phase adds the `lateMODULE` flag to trait implementation classes. Since the flag - // is late, it should not be visible here inside the time travel. We check this. - if (r) assert(!sym.isImplClass, s"isModuleClass should be false for impl class $sym") - r + sym.isModuleClass && !sym.isNestedClass } /** * True for module classes of modules that are top-level or owned only by objects. Module classes - * for such objects will get a MODULE$ flag and a corresponding static initializer. + * for such objects will get a MODULE$ field and a corresponding static initializer. */ final def isStaticModuleClass(sym: Symbol): Boolean = { - /* (1) Phase travel to to pickler is required to exclude implementation classes; they have the - * lateMODULEs after mixin, so isModuleClass would be true. - * (2) isStaticModuleClass is a source-level property. See comment on isOriginallyStaticOwner. - */ - exitingPickler { // (1) - sym.isModuleClass && - isOriginallyStaticOwner(sym.originalOwner) // (2) - } + sym.isModuleClass && + isOriginallyStaticOwner(sym.originalOwner) // isStaticModuleClass is a source-level property, see comment on isOriginallyStaticOwner } // legacy, to be removed when the @remote annotation gets removed @@ -559,7 +644,7 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { val finalFlag = ( (((sym.rawflags & symtab.Flags.FINAL) != 0) || isTopLevelModuleClass(sym)) - && !sym.enclClass.isInterface + && !sym.enclClass.isTrait && !sym.isClassConstructor && !sym.isMutable // lazy vals and vars both ) @@ -567,17 +652,17 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes { // Primitives are "abstract final" to prohibit instantiation // without having to provide any implementations, but that is an // illegal combination of modifiers at the bytecode level so - // suppress final if abstract if present. + // suppress final if abstract is present. import asm.Opcodes._ GenBCode.mkFlags( if (privateFlag) ACC_PRIVATE else ACC_PUBLIC, - if (sym.isDeferred || sym.hasAbstractFlag) ACC_ABSTRACT else 0, - if (sym.isInterface) ACC_INTERFACE else 0, + if ((sym.isDeferred && !sym.hasFlag(symtab.Flags.JAVA_DEFAULTMETHOD))|| sym.hasAbstractFlag) ACC_ABSTRACT else 0, + if (sym.isTraitOrInterface) ACC_INTERFACE else 0, if (finalFlag && !sym.hasAbstractFlag) ACC_FINAL else 0, if (sym.isStaticMember) ACC_STATIC else 0, if (sym.isBridge) ACC_BRIDGE | ACC_SYNTHETIC else 0, if (sym.isArtifact) ACC_SYNTHETIC else 0, - if (sym.isClass && !sym.isInterface) ACC_SUPER else 0, + if (sym.isClass && !sym.isTraitOrInterface) ACC_SUPER else 0, if (sym.hasJavaEnumFlag) ACC_ENUM else 0, if (sym.isVarargsMethod) ACC_VARARGS else 0, if (sym.hasFlag(symtab.Flags.SYNCHRONIZED)) ACC_SYNCHRONIZED else 0, |