diff options
Diffstat (limited to 'src/reflect/scala/reflect/internal/pickling/UnPickler.scala')
-rw-r--r-- | src/reflect/scala/reflect/internal/pickling/UnPickler.scala | 871 |
1 files changed, 871 insertions, 0 deletions
diff --git a/src/reflect/scala/reflect/internal/pickling/UnPickler.scala b/src/reflect/scala/reflect/internal/pickling/UnPickler.scala new file mode 100644 index 0000000000..757163a074 --- /dev/null +++ b/src/reflect/scala/reflect/internal/pickling/UnPickler.scala @@ -0,0 +1,871 @@ +/* NSC -- new Scala compiler + * Copyright 2005-2011 LAMP/EPFL + * @author Martin Odersky + */ + +package scala.reflect +package internal +package pickling + +import java.io.IOException +import java.lang.Float.intBitsToFloat +import java.lang.Double.longBitsToDouble + +import Flags._ +import PickleFormat._ +import scala.collection.{ mutable, immutable } +import collection.mutable.ListBuffer +import annotation.switch + +/** @author Martin Odersky + * @version 1.0 + */ +abstract class UnPickler /*extends reflect.generic.UnPickler*/ { + val global: SymbolTable + import global._ + + /** Unpickle symbol table information descending from a class and/or module root + * from an array of bytes. + * @param bytes bytearray from which we unpickle + * @param offset offset from which unpickling starts + * @param classroot the top-level class which is unpickled, or NoSymbol if inapplicable + * @param moduleroot the top-level module which is unpickled, or NoSymbol if inapplicable + * @param filename filename associated with bytearray, only used for error messages + */ + def unpickle(bytes: Array[Byte], offset: Int, classRoot: Symbol, moduleRoot: Symbol, filename: String) { + try { + new Scan(bytes, offset, classRoot, moduleRoot, filename).run() + } catch { + case ex: IOException => + throw ex + case ex: MissingRequirementError => + throw ex + case ex: Throwable => + /*if (settings.debug.value)*/ ex.printStackTrace() + throw new RuntimeException("error reading Scala signature of "+filename+": "+ex.getMessage()) + } + } + + class Scan(_bytes: Array[Byte], offset: Int, classRoot: Symbol, moduleRoot: Symbol, filename: String) extends PickleBuffer(_bytes, offset, -1) { + //println("unpickle " + classRoot + " and " + moduleRoot)//debug + + protected def debug = settings.debug.value + + checkVersion() + + private val loadingMirror = mirrorThatLoaded(classRoot) + + /** A map from entry numbers to array offsets */ + private val index = createIndex + + /** A map from entry numbers to symbols, types, or annotations */ + private val entries = new Array[AnyRef](index.length) + + /** A map from symbols to their associated `decls` scopes */ + private val symScopes = mutable.HashMap[Symbol, Scope]() + + //println("unpickled " + classRoot + ":" + classRoot.rawInfo + ", " + moduleRoot + ":" + moduleRoot.rawInfo);//debug + + // Laboriously unrolled for performance. + def run() { + var i = 0 + while (i < index.length) { + if (entries(i) == null && isSymbolEntry(i)) { + val savedIndex = readIndex + readIndex = index(i) + entries(i) = readSymbol() + readIndex = savedIndex + } + i += 1 + } + // read children last, fix for #3951 + i = 0 + while (i < index.length) { + if (entries(i) == null) { + if (isSymbolAnnotationEntry(i)) { + val savedIndex = readIndex + readIndex = index(i) + readSymbolAnnotation() + readIndex = savedIndex + } + else if (isChildrenEntry(i)) { + val savedIndex = readIndex + readIndex = index(i) + readChildren() + readIndex = savedIndex + } + } + i += 1 + } + } + + private def checkVersion() { + val major = readNat() + val minor = readNat() + if (major != MajorVersion || minor > MinorVersion) + throw new IOException("Scala signature " + classRoot.decodedName + + " has wrong version\n expected: " + + MajorVersion + "." + MinorVersion + + "\n found: " + major + "." + minor + + " in "+filename) + } + + /** The `decls` scope associated with given symbol */ + protected def symScope(sym: Symbol) = symScopes.getOrElseUpdate(sym, newScope) + + /** Does entry represent an (internal) symbol */ + protected def isSymbolEntry(i: Int): Boolean = { + val tag = bytes(index(i)).toInt + (firstSymTag <= tag && tag <= lastSymTag && + (tag != CLASSsym || !isRefinementSymbolEntry(i))) + } + + /** Does entry represent an (internal or external) symbol */ + protected def isSymbolRef(i: Int): Boolean = { + val tag = bytes(index(i)) + (firstSymTag <= tag && tag <= lastExtSymTag) + } + + /** Does entry represent a name? */ + protected def isNameEntry(i: Int): Boolean = { + val tag = bytes(index(i)).toInt + tag == TERMname || tag == TYPEname + } + + /** Does entry represent a symbol annotation? */ + protected def isSymbolAnnotationEntry(i: Int): Boolean = { + val tag = bytes(index(i)).toInt + tag == SYMANNOT + } + + /** Does the entry represent children of a symbol? */ + protected def isChildrenEntry(i: Int): Boolean = { + val tag = bytes(index(i)).toInt + tag == CHILDREN + } + + /** Does entry represent a refinement symbol? + * pre: Entry is a class symbol + */ + protected def isRefinementSymbolEntry(i: Int): Boolean = { + val savedIndex = readIndex + readIndex = index(i) + val tag = readByte().toInt + assert(tag == CLASSsym) + + readNat(); // read length + val result = readNameRef() == tpnme.REFINE_CLASS_NAME + readIndex = savedIndex + result + } + + /** If entry at <code>i</code> is undefined, define it by performing + * operation <code>op</code> with <code>readIndex at start of i'th + * entry. Restore <code>readIndex</code> afterwards. + */ + protected def at[T <: AnyRef](i: Int, op: () => T): T = { + var r = entries(i) + if (r eq null) { + val savedIndex = readIndex + readIndex = index(i) + r = op() + assert(entries(i) eq null, entries(i)) + entries(i) = r + readIndex = savedIndex + } + r.asInstanceOf[T] + } + + /** Read a name */ + protected def readName(): Name = { + val tag = readByte() + val len = readNat() + tag match { + case TERMname => newTermName(bytes, readIndex, len) + case TYPEname => newTypeName(bytes, readIndex, len) + case _ => errorBadSignature("bad name tag: " + tag) + } + } + protected def readTermName(): TermName = readName().toTermName + protected def readTypeName(): TypeName = readName().toTypeName + + /** Read a symbol */ + protected def readSymbol(): Symbol = { + val tag = readByte() + val end = readNat() + readIndex + def atEnd = readIndex == end + + def readExtSymbol(): Symbol = { + val name = readNameRef() + val owner = if (atEnd) loadingMirror.RootClass else readSymbolRef() + + def adjust(sym: Symbol) = if (tag == EXTref) sym else sym.moduleClass + + def fromName(name: Name) = name.toTermName match { + case nme.ROOT => loadingMirror.RootClass + case nme.ROOTPKG => loadingMirror.RootPackage + case _ => adjust(owner.info.decl(name)) + } + def nestedObjectSymbol: Symbol = { + // If the owner is overloaded (i.e. a method), it's not possible to select the + // right member, so return NoSymbol. This can only happen when unpickling a tree. + // the "case Apply" in readTree() takes care of selecting the correct alternative + // after parsing the arguments. + if (owner.isOverloaded) + return NoSymbol + + if (tag == EXTMODCLASSref) { + val moduleVar = owner.info.decl(nme.moduleVarName(name.toTermName)) + if (moduleVar.isLazyAccessor) + return moduleVar.lazyAccessor.lazyAccessor + } + NoSymbol + } + + // (1) Try name. + fromName(name) orElse { + // (2) Try with expanded name. Can happen if references to private + // symbols are read from outside: for instance when checking the children + // of a class. See #1722. + fromName(nme.expandedName(name.toTermName, owner)) orElse { + // (3) Try as a nested object symbol. + nestedObjectSymbol orElse { + // (4) Otherwise, fail. + //System.err.println("missing "+name+" in "+owner+"/"+owner.id+" "+owner.info.decls) + adjust(errorMissingRequirement(name, owner)) + } + } + } + } + + tag match { + case NONEsym => return NoSymbol + case EXTref | EXTMODCLASSref => return readExtSymbol() + case _ => () + } + + // symbols that were pickled with Pickler.writeSymInfo + val nameref = readNat() + val name = at(nameref, readName) + val owner = readSymbolRef() + val flags = pickledToRawFlags(readLongNat()) + var inforef = readNat() + val privateWithin = + if (!isSymbolRef(inforef)) NoSymbol + else { + val pw = at(inforef, readSymbol) + inforef = readNat() + pw + } + + def isModuleFlag = (flags & MODULE) != 0L + def isClassRoot = (name == classRoot.name) && (owner == classRoot.owner) + def isModuleRoot = (name == moduleRoot.name) && (owner == moduleRoot.owner) + def pflags = flags & PickledFlags + + def finishSym(sym: Symbol): Symbol = { + sym.privateWithin = privateWithin + sym.info = ( + if (atEnd) { + assert(!sym.isSuperAccessor, sym) + newLazyTypeRef(inforef) + } + else { + assert(sym.isSuperAccessor || sym.isParamAccessor, sym) + newLazyTypeRefAndAlias(inforef, readNat()) + } + ) + if (sym.owner.isClass && sym != classRoot && sym != moduleRoot && + !sym.isModuleClass && !sym.isRefinementClass && !sym.isTypeParameter && !sym.isExistentiallyBound) + symScope(sym.owner) enter sym + + sym + } + + finishSym(tag match { + case TYPEsym | ALIASsym => + owner.newNonClassSymbol(name.toTypeName, NoPosition, pflags) + case CLASSsym => + val sym = ( + if (isClassRoot) { + if (isModuleFlag) moduleRoot.moduleClass setFlag pflags + else classRoot setFlag pflags + } + else owner.newClassSymbol(name.toTypeName, NoPosition, pflags) + ) + if (!atEnd) + sym.typeOfThis = newLazyTypeRef(readNat()) + + sym + case MODULEsym => + val clazz = at(inforef, () => readType()).typeSymbol // after the NMT_TRANSITION period, we can leave off the () => ... () + if (isModuleRoot) moduleRoot setFlag pflags + else owner.newLinkedModule(clazz, pflags) + case VALsym => + if (isModuleRoot) { assert(false); NoSymbol } + else owner.newTermSymbol(name.toTermName, NoPosition, pflags) + + case _ => + errorBadSignature("bad symbol tag: " + tag) + }) + } + + /** Read a type + * + * @param forceProperType is used to ease the transition to NullaryMethodTypes (commentmarker: NMT_TRANSITION) + * the flag say that a type of kind * is expected, so that PolyType(tps, restpe) can be disambiguated to PolyType(tps, NullaryMethodType(restpe)) + * (if restpe is not a ClassInfoType, a MethodType or a NullaryMethodType, which leaves TypeRef/SingletonType -- the latter would make the polytype a type constructor) + */ + protected def readType(forceProperType: Boolean = false): Type = { + val tag = readByte() + val end = readNat() + readIndex + (tag: @switch) match { + case NOtpe => + NoType + case NOPREFIXtpe => + NoPrefix + case THIStpe => + ThisType(readSymbolRef()) + case SINGLEtpe => + SingleType(readTypeRef(), readSymbolRef()) // !!! was singleType + case SUPERtpe => + val thistpe = readTypeRef() + val supertpe = readTypeRef() + SuperType(thistpe, supertpe) + case CONSTANTtpe => + ConstantType(readConstantRef()) + case TYPEREFtpe => + val pre = readTypeRef() + val sym = readSymbolRef() + var args = until(end, readTypeRef) + TypeRef(pre, sym, args) + case TYPEBOUNDStpe => + TypeBounds(readTypeRef(), readTypeRef()) + case REFINEDtpe => + val clazz = readSymbolRef() + RefinedType(until(end, readTypeRef), symScope(clazz), clazz) + case CLASSINFOtpe => + val clazz = readSymbolRef() + ClassInfoType(until(end, readTypeRef), symScope(clazz), clazz) + case METHODtpe | IMPLICITMETHODtpe => + val restpe = readTypeRef() + val params = until(end, readSymbolRef) + // if the method is overloaded, the params cannot be determined (see readSymbol) => return NoType. + // Only happen for trees, "case Apply" in readTree() takes care of selecting the correct + // alternative after parsing the arguments. + if (params.contains(NoSymbol) || restpe == NoType) NoType + else MethodType(params, restpe) + case POLYtpe => + val restpe = readTypeRef() + val typeParams = until(end, readSymbolRef) + if (typeParams.nonEmpty) { + // NMT_TRANSITION: old class files denoted a polymorphic nullary method as PolyType(tps, restpe), we now require PolyType(tps, NullaryMethodType(restpe)) + // when a type of kind * is expected (forceProperType is true), we know restpe should be wrapped in a NullaryMethodType (if it wasn't suitably wrapped yet) + def transitionNMT(restpe: Type) = { + val resTpeCls = restpe.getClass.toString // what's uglier than isInstanceOf? right! -- isInstanceOf does not work since the concrete types are defined in the compiler (not in scope here) + if(forceProperType /*&& pickleformat < 2.9 */ && !(resTpeCls.endsWith("MethodType"))) { assert(!resTpeCls.contains("ClassInfoType")) + NullaryMethodType(restpe) } + else restpe + } + PolyType(typeParams, transitionNMT(restpe)) + } + else + NullaryMethodType(restpe) + case EXISTENTIALtpe => + val restpe = readTypeRef() + // @PP: Where is the flag setting supposed to happen? I infer + // from the lack of flag setting in the rest of the unpickler + // that it isn't right here. See #4757 for the immediate + // motivation to fix it. + val tparams = until(end, readSymbolRef) map (_ setFlag EXISTENTIAL) + newExistentialType(tparams, restpe) + + case ANNOTATEDtpe => + var typeRef = readNat() + val selfsym = if (isSymbolRef(typeRef)) { + val s = at(typeRef, readSymbol) + typeRef = readNat() + s + } else NoSymbol // selfsym can go. + val tp = at(typeRef, () => readType(forceProperType)) // NMT_TRANSITION + val annots = until(end, readAnnotationRef) + if (selfsym == NoSymbol) AnnotatedType(annots, tp, selfsym) + else tp + case _ => + noSuchTypeTag(tag, end) + } + } + + def noSuchTypeTag(tag: Int, end: Int): Type = + errorBadSignature("bad type tag: " + tag) + + /** Read a constant */ + protected def readConstant(): Constant = { + val tag = readByte().toInt + val len = readNat() + (tag: @switch) match { + case LITERALunit => Constant(()) + case LITERALboolean => Constant(readLong(len) != 0L) + case LITERALbyte => Constant(readLong(len).toByte) + case LITERALshort => Constant(readLong(len).toShort) + case LITERALchar => Constant(readLong(len).toChar) + case LITERALint => Constant(readLong(len).toInt) + case LITERALlong => Constant(readLong(len)) + case LITERALfloat => Constant(intBitsToFloat(readLong(len).toInt)) + case LITERALdouble => Constant(longBitsToDouble(readLong(len))) + case LITERALstring => Constant(readNameRef().toString) + case LITERALnull => Constant(null) + case LITERALclass => Constant(readTypeRef()) + case LITERALenum => Constant(readSymbolRef()) + case _ => noSuchConstantTag(tag, len) + } + } + + def noSuchConstantTag(tag: Int, len: Int): Constant = + errorBadSignature("bad constant tag: " + tag) + + /** Read children and store them into the corresponding symbol. + */ + protected def readChildren() { + val tag = readByte() + assert(tag == CHILDREN) + val end = readNat() + readIndex + val target = readSymbolRef() + while (readIndex != end) target addChild readSymbolRef() + } + + /** Read an annotation argument, which is pickled either + * as a Constant or a Tree. + */ + protected def readAnnotArg(i: Int): Tree = bytes(index(i)) match { + case TREE => at(i, readTree) + case _ => + val const = at(i, readConstant) + Literal(const) setType const.tpe + } + + /** Read a ClassfileAnnotArg (argument to a classfile annotation) + */ + private def readArrayAnnot() = { + readByte() // skip the `annotargarray` tag + val end = readNat() + readIndex + until(end, () => readClassfileAnnotArg(readNat())).toArray(ClassfileAnnotArgTag) + } + protected def readClassfileAnnotArg(i: Int): ClassfileAnnotArg = bytes(index(i)) match { + case ANNOTINFO => NestedAnnotArg(at(i, readAnnotation)) + case ANNOTARGARRAY => at(i, () => ArrayAnnotArg(readArrayAnnot())) + case _ => LiteralAnnotArg(at(i, readConstant)) + } + + /** Read an AnnotationInfo. Not to be called directly, use + * readAnnotation or readSymbolAnnotation + */ + protected def readAnnotationInfo(end: Int): AnnotationInfo = { + val atp = readTypeRef() + val args = new ListBuffer[Tree] + val assocs = new ListBuffer[(Name, ClassfileAnnotArg)] + while (readIndex != end) { + val argref = readNat() + if (isNameEntry(argref)) { + val name = at(argref, readName) + val arg = readClassfileAnnotArg(readNat()) + assocs += ((name, arg)) + } + else + args += readAnnotArg(argref) + } + AnnotationInfo(atp, args.toList, assocs.toList) + } + + /** Read an annotation and as a side effect store it into + * the symbol it requests. Called at top-level, for all + * (symbol, annotInfo) entries. */ + protected def readSymbolAnnotation() { + val tag = readByte() + if (tag != SYMANNOT) + errorBadSignature("symbol annotation expected ("+ tag +")") + val end = readNat() + readIndex + val target = readSymbolRef() + target.addAnnotation(readAnnotationInfo(end)) + } + + /** Read an annotation and return it. Used when unpickling + * an ANNOTATED(WSELF)tpe or a NestedAnnotArg */ + protected def readAnnotation(): AnnotationInfo = { + val tag = readByte() + if (tag != ANNOTINFO) + errorBadSignature("annotation expected (" + tag + ")") + val end = readNat() + readIndex + readAnnotationInfo(end) + } + + /* Read an abstract syntax tree */ + protected def readTree(): Tree = { + val outerTag = readByte() + if (outerTag != TREE) + errorBadSignature("tree expected (" + outerTag + ")") + val end = readNat() + readIndex + val tag = readByte() + val tpe = if (tag == EMPTYtree) NoType else readTypeRef() + + // Set by the three functions to follow. If symbol is non-null + // after the new tree 't' has been created, t has its Symbol + // set to symbol; and it always has its Type set to tpe. + var symbol: Symbol = null + var mods: Modifiers = null + var name: Name = null + + /** Read a Symbol, Modifiers, and a Name */ + def setSymModsName() { + symbol = readSymbolRef() + mods = readModifiersRef() + name = readNameRef() + } + /** Read a Symbol and a Name */ + def setSymName() { + symbol = readSymbolRef() + name = readNameRef() + } + /** Read a Symbol */ + def setSym() { + symbol = readSymbolRef() + } + + val t = tag match { + case EMPTYtree => + EmptyTree + + case PACKAGEtree => + setSym() + val pid = readTreeRef().asInstanceOf[RefTree] + val stats = until(end, readTreeRef) + PackageDef(pid, stats) + + case CLASStree => + setSymModsName() + val impl = readTemplateRef() + val tparams = until(end, readTypeDefRef) + ClassDef(mods, name.toTypeName, tparams, impl) + + case MODULEtree => + setSymModsName() + ModuleDef(mods, name.toTermName, readTemplateRef()) + + case VALDEFtree => + setSymModsName() + val tpt = readTreeRef() + val rhs = readTreeRef() + ValDef(mods, name.toTermName, tpt, rhs) + + case DEFDEFtree => + setSymModsName() + val tparams = times(readNat(), readTypeDefRef) + val vparamss = times(readNat(), () => times(readNat(), readValDefRef)) + val tpt = readTreeRef() + val rhs = readTreeRef() + DefDef(mods, name.toTermName, tparams, vparamss, tpt, rhs) + + case TYPEDEFtree => + setSymModsName() + val rhs = readTreeRef() + val tparams = until(end, readTypeDefRef) + TypeDef(mods, name.toTypeName, tparams, rhs) + + case LABELtree => + setSymName() + val rhs = readTreeRef() + val params = until(end, readIdentRef) + LabelDef(name.toTermName, params, rhs) + + case IMPORTtree => + setSym() + val expr = readTreeRef() + val selectors = until(end, () => { + val from = readNameRef() + val to = readNameRef() + ImportSelector(from, -1, to, -1) + }) + + Import(expr, selectors) + + case TEMPLATEtree => + setSym() + val parents = times(readNat(), readTreeRef) + val self = readValDefRef() + val body = until(end, readTreeRef) + + Template(parents, self, body) + + case BLOCKtree => + val expr = readTreeRef() + val stats = until(end, readTreeRef) + Block(stats, expr) + + case CASEtree => + val pat = readTreeRef() + val guard = readTreeRef() + val body = readTreeRef() + CaseDef(pat, guard, body) + + case ALTERNATIVEtree => + Alternative(until(end, readTreeRef)) + + case STARtree => + Star(readTreeRef()) + + case BINDtree => + setSymName() + Bind(name, readTreeRef()) + + case UNAPPLYtree => + val fun = readTreeRef() + val args = until(end, readTreeRef) + UnApply(fun, args) + + case ARRAYVALUEtree => + val elemtpt = readTreeRef() + val trees = until(end, readTreeRef) + ArrayValue(elemtpt, trees) + + case FUNCTIONtree => + setSym() + val body = readTreeRef() + val vparams = until(end, readValDefRef) + Function(vparams, body) + + case ASSIGNtree => + val lhs = readTreeRef() + val rhs = readTreeRef() + Assign(lhs, rhs) + + case IFtree => + val cond = readTreeRef() + val thenp = readTreeRef() + val elsep = readTreeRef() + If(cond, thenp, elsep) + + case MATCHtree => + val selector = readTreeRef() + val cases = until(end, readCaseDefRef) + Match(selector, cases) + + case RETURNtree => + setSym() + Return(readTreeRef()) + + case TREtree => + val block = readTreeRef() + val finalizer = readTreeRef() + val catches = until(end, readCaseDefRef) + Try(block, catches, finalizer) + + case THROWtree => + Throw(readTreeRef()) + + case NEWtree => + New(readTreeRef()) + + case TYPEDtree => + val expr = readTreeRef() + val tpt = readTreeRef() + Typed(expr, tpt) + + case TYPEAPPLYtree => + val fun = readTreeRef() + val args = until(end, readTreeRef) + TypeApply(fun, args) + + case APPLYtree => + val fun = readTreeRef() + val args = until(end, readTreeRef) + if (fun.symbol.isOverloaded) { + fun.setType(fun.symbol.info) + inferMethodAlternative(fun, args map (_.tpe), tpe) + } + Apply(fun, args) + + case APPLYDYNAMICtree => + setSym() + val qual = readTreeRef() + val args = until(end, readTreeRef) + ApplyDynamic(qual, args) + + case SUPERtree => + setSym() + val qual = readTreeRef() + val mix = readTypeNameRef() + Super(qual, mix) + + case THIStree => + setSym() + This(readTypeNameRef()) + + case SELECTtree => + setSym() + val qualifier = readTreeRef() + val selector = readNameRef() + Select(qualifier, selector) + + case IDENTtree => + setSymName() + Ident(name) + + case LITERALtree => + Literal(readConstantRef()) + + case TYPEtree => + TypeTree() + + case ANNOTATEDtree => + val annot = readTreeRef() + val arg = readTreeRef() + Annotated(annot, arg) + + case SINGLETONTYPEtree => + SingletonTypeTree(readTreeRef()) + + case SELECTFROMTYPEtree => + val qualifier = readTreeRef() + val selector = readTypeNameRef() + SelectFromTypeTree(qualifier, selector) + + case COMPOUNDTYPEtree => + CompoundTypeTree(readTemplateRef()) + + case APPLIEDTYPEtree => + val tpt = readTreeRef() + val args = until(end, readTreeRef) + AppliedTypeTree(tpt, args) + + case TYPEBOUNDStree => + val lo = readTreeRef() + val hi = readTreeRef() + TypeBoundsTree(lo, hi) + + case EXISTENTIALTYPEtree => + val tpt = readTreeRef() + val whereClauses = until(end, readTreeRef) + ExistentialTypeTree(tpt, whereClauses) + + case _ => + noSuchTreeTag(tag, end) + } + + if (symbol == null) t setType tpe + else t setSymbol symbol setType tpe + } + + def noSuchTreeTag(tag: Int, end: Int) = + errorBadSignature("unknown tree type (" + tag + ")") + + def readModifiers(): Modifiers = { + val tag = readNat() + if (tag != MODIFIERS) + errorBadSignature("expected a modifiers tag (" + tag + ")") + val end = readNat() + readIndex + val pflagsHi = readNat() + val pflagsLo = readNat() + val pflags = (pflagsHi.toLong << 32) + pflagsLo + val flags = pickledToRawFlags(pflags) + val privateWithin = readNameRef() + Modifiers(flags, privateWithin, Nil) + } + + /* Read a reference to a pickled item */ + protected def readNameRef(): Name = at(readNat(), readName) + protected def readSymbolRef(): Symbol = at(readNat(), readSymbol) + protected def readTypeRef(): Type = at(readNat(), () => readType()) // after the NMT_TRANSITION period, we can leave off the () => ... () + protected def readConstantRef(): Constant = at(readNat(), readConstant) + protected def readAnnotationRef(): AnnotationInfo = at(readNat(), readAnnotation) + protected def readModifiersRef(): Modifiers = at(readNat(), readModifiers) + protected def readTreeRef(): Tree = at(readNat(), readTree) + + protected def readTypeNameRef(): TypeName = readNameRef().toTypeName + protected def readTermNameRef(): TermName = readNameRef().toTermName + + protected def readTemplateRef(): Template = + readTreeRef() match { + case templ:Template => templ + case other => + errorBadSignature("expected a template (" + other + ")") + } + protected def readCaseDefRef(): CaseDef = + readTreeRef() match { + case tree:CaseDef => tree + case other => + errorBadSignature("expected a case def (" + other + ")") + } + protected def readValDefRef(): ValDef = + readTreeRef() match { + case tree:ValDef => tree + case other => + errorBadSignature("expected a ValDef (" + other + ")") + } + protected def readIdentRef(): Ident = + readTreeRef() match { + case tree:Ident => tree + case other => + errorBadSignature("expected an Ident (" + other + ")") + } + protected def readTypeDefRef(): TypeDef = + readTreeRef() match { + case tree:TypeDef => tree + case other => + errorBadSignature("expected an TypeDef (" + other + ")") + } + + protected def errorBadSignature(msg: String) = + throw new RuntimeException("malformed Scala signature of " + classRoot.name + " at " + readIndex + "; " + msg) + + protected def errorMissingRequirement(name: Name, owner: Symbol): Symbol = + missingHook(owner, name) orElse MissingRequirementError.signal( + s"bad reference while unpickling $filename: ${name.longString} not found in ${owner.tpe.widen}" + ) + + def inferMethodAlternative(fun: Tree, argtpes: List[Type], restpe: Type) {} // can't do it; need a compiler for that. + + def newLazyTypeRef(i: Int): LazyType = new LazyTypeRef(i) + def newLazyTypeRefAndAlias(i: Int, j: Int): LazyType = new LazyTypeRefAndAlias(i, j) + + /** Convert to a type error, that is printed gracefully instead of crashing. + * + * Similar in intent to what SymbolLoader does (but here we don't have access to + * error reporting, so we rely on the typechecker to report the error). + */ + def toTypeError(e: MissingRequirementError) = + new TypeError(e.msg) + + /** A lazy type which when completed returns type at index `i`. */ + private class LazyTypeRef(i: Int) extends LazyType { + private val definedAtRunId = currentRunId + private val p = phase + override def complete(sym: Symbol) : Unit = try { + val tp = at(i, () => readType(sym.isTerm)) // after NMT_TRANSITION, revert `() => readType(sym.isTerm)` to `readType` + atPhase(p) (sym setInfo tp) + if (currentRunId != definedAtRunId) + sym.setInfo(adaptToNewRunMap(tp)) + } + catch { + case e: MissingRequirementError => throw toTypeError(e) + } + override def load(sym: Symbol) { complete(sym) } + } + + /** A lazy type which when completed returns type at index `i` and sets alias + * of completed symbol to symbol at index `j`. + */ + private class LazyTypeRefAndAlias(i: Int, j: Int) extends LazyTypeRef(i) { + override def complete(sym: Symbol) = try { + super.complete(sym) + var alias = at(j, readSymbol) + if (alias.isOverloaded) + alias = atPhase(picklerPhase)((alias suchThat (alt => sym.tpe =:= sym.owner.thisType.memberType(alt)))) + + sym.asInstanceOf[TermSymbol].setAlias(alias) + } + catch { + case e: MissingRequirementError => throw toTypeError(e) + } + } + } +} |