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-rw-r--r--src/compiler/scala/tools/nsc/backend/icode/GenICode.scala2
-rw-r--r--src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala28
-rw-r--r--src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala2
-rw-r--r--src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala24
-rw-r--r--src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala18
-rw-r--r--src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala2
-rw-r--r--src/compiler/scala/tools/nsc/settings/ScalaSettings.scala1
-rw-r--r--src/compiler/scala/tools/nsc/transform/Erasure.scala18
-rw-r--r--src/compiler/scala/tools/nsc/transform/patmat/Logic.scala17
-rw-r--r--src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala124
-rw-r--r--src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala9
-rw-r--r--src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala18
-rw-r--r--src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala38
-rw-r--r--src/compiler/scala/tools/nsc/transform/patmat/Solving.scala62
-rw-r--r--src/compiler/scala/tools/nsc/typechecker/Typers.scala24
15 files changed, 253 insertions, 134 deletions
diff --git a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala b/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala
index f385acdb41..cf52ad6636 100644
--- a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala
+++ b/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala
@@ -1495,7 +1495,7 @@ abstract class GenICode extends SubComponent {
if (!settings.optimise) {
if (l.tpe <:< BoxedNumberClass.tpe) {
if (r.tpe <:< BoxedNumberClass.tpe) platform.externalEqualsNumNum
- else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumChar
+ else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumObject // will be externalEqualsNumChar in 2.12, SI-9030
else platform.externalEqualsNumObject
} else platform.externalEquals
} else {
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala
index 328ec8a033..a5f33aa786 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeAsmCommon.scala
@@ -162,4 +162,32 @@ final class BCodeAsmCommon[G <: Global](val global: G) {
assoc.collectFirst {
case (`nme`.value, LiteralAnnotArg(Constant(value: Symbol))) => value
}).flatten.getOrElse(AnnotationRetentionPolicyClassValue)
+
+ 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
+ }
+
+ def isInterfaceOrTrait(sym: Symbol) = sym.isInterface || sym.isTrait
+
+ val allParents = classSym.info.parents ++ 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)
+ }
}
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala b/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala
index daf36ce374..062daa4eac 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/BCodeBodyBuilder.scala
@@ -1225,7 +1225,7 @@ abstract class BCodeBodyBuilder extends BCodeSkelBuilder {
val equalsMethod: Symbol = {
if (l.tpe <:< BoxedNumberClass.tpe) {
if (r.tpe <:< BoxedNumberClass.tpe) platform.externalEqualsNumNum
- else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumChar
+ else if (r.tpe <:< BoxedCharacterClass.tpe) platform.externalEqualsNumObject // will be externalEqualsNumChar in 2.12, SI-9030
else platform.externalEqualsNumObject
} else platform.externalEquals
}
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala b/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala
index e3b812f413..a0b8d28f18 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/BTypesFromSymbols.scala
@@ -114,7 +114,7 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes {
val superClass = if (superClassSym == NoSymbol) None
else Some(classBTypeFromSymbol(superClassSym))
- val interfaces = getSuperInterfaces(classSym).map(classBTypeFromSymbol)
+ val interfaces = implementedInterfaces(classSym).map(classBTypeFromSymbol)
val flags = javaFlags(classSym)
@@ -182,28 +182,6 @@ class BTypesFromSymbols[G <: Global](val global: G) extends BTypes {
classBType
}
- /**
- * All interfaces implemented by a class, except for those inherited through the superclass.
- *
- * TODO @lry share code with GenASM
- */
- private def getSuperInterfaces(classSym: Symbol): List[Symbol] = {
-
- // Additional interface parents based on annotations and other cues
- def newParentForAnnotation(ann: AnnotationInfo): Symbol = ann.symbol match {
- case RemoteAttr => RemoteInterfaceClass
- case _ => NoSymbol
- }
-
- val superInterfaces0: List[Symbol] = classSym.mixinClasses
- val superInterfaces = existingSymbols(superInterfaces0 ++ classSym.annotations.map(newParentForAnnotation)).distinct
-
- assert(!superInterfaces.contains(NoSymbol), s"found NoSymbol among: ${superInterfaces.mkString(", ")}")
- assert(superInterfaces.forall(s => s.isInterface || s.isTrait), s"found non-interface among: ${superInterfaces.mkString(", ")}")
-
- erasure.minimizeInterfaces(superInterfaces.map(_.info)).map(_.typeSymbol)
- }
-
private def buildNestedInfo(innerClassSym: Symbol): Option[NestedInfo] = {
assert(innerClassSym.isClass, s"Cannot build NestedInfo for non-class symbol $innerClassSym")
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala b/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala
index 4373d997b8..de468c0a6d 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/GenASM.scala
@@ -1206,22 +1206,6 @@ abstract class GenASM extends SubComponent with BytecodeWriters { self =>
def serialVUID: Option[Long] = genBCode.serialVUID(clasz.symbol)
- private def getSuperInterfaces(c: IClass): Array[String] = {
-
- // Additional interface parents based on annotations and other cues
- def newParentForAttr(ann: AnnotationInfo): Symbol = ann.symbol match {
- case RemoteAttr => RemoteInterfaceClass
- case _ => NoSymbol
- }
-
- val ps = c.symbol.info.parents
- val superInterfaces0: List[Symbol] = if(ps.isEmpty) Nil else c.symbol.mixinClasses
- val superInterfaces = existingSymbols(superInterfaces0 ++ c.symbol.annotations.map(newParentForAttr)).distinct
-
- if(superInterfaces.isEmpty) EMPTY_STRING_ARRAY
- else mkArray(erasure.minimizeInterfaces(superInterfaces.map(_.info)).map(t => javaName(t.typeSymbol)))
- }
-
var clasz: IClass = _ // this var must be assigned only by genClass()
var jclass: asm.ClassWriter = _ // the classfile being emitted
var thisName: String = _ // the internal name of jclass
@@ -1242,7 +1226,7 @@ abstract class GenASM extends SubComponent with BytecodeWriters { self =>
val ps = c.symbol.info.parents
val superClass: String = if(ps.isEmpty) JAVA_LANG_OBJECT.getInternalName else javaName(ps.head.typeSymbol)
- val ifaces = getSuperInterfaces(c)
+ val ifaces: Array[String] = implementedInterfaces(c.symbol).map(javaName)(collection.breakOut)
val thisSignature = getGenericSignature(c.symbol, c.symbol.owner)
val flags = mkFlags(
diff --git a/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala b/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala
index 3bd2e5c4f4..87ad715e4d 100644
--- a/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala
+++ b/src/compiler/scala/tools/nsc/backend/jvm/opt/LocalOpt.scala
@@ -55,7 +55,7 @@ class LocalOpt(settings: ScalaSettings) {
* @return `true` if unreachable code was eliminated in some method, `false` otherwise.
*/
def methodOptimizations(clazz: ClassNode): Boolean = {
- settings.Yopt.value.nonEmpty && clazz.methods.asScala.foldLeft(false) {
+ !settings.YoptNone && clazz.methods.asScala.foldLeft(false) {
case (changed, method) => methodOptimizations(method, clazz.name) || changed
}
}
diff --git a/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala b/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala
index c645a837cc..a5b722612d 100644
--- a/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala
+++ b/src/compiler/scala/tools/nsc/settings/ScalaSettings.scala
@@ -242,6 +242,7 @@ trait ScalaSettings extends AbsScalaSettings
descr = "Enable optimizations",
domain = YoptChoices)
+ def YoptNone = Yopt.isSetByUser && Yopt.value.isEmpty
def YoptUnreachableCode = !Yopt.isSetByUser || Yopt.contains(YoptChoices.unreachableCode)
def YoptSimplifyJumps = Yopt.contains(YoptChoices.simplifyJumps)
def YoptRecurseUnreachableJumps = Yopt.contains(YoptChoices.recurseUnreachableJumps)
diff --git a/src/compiler/scala/tools/nsc/transform/Erasure.scala b/src/compiler/scala/tools/nsc/transform/Erasure.scala
index efe77995cc..5c72bb3258 100644
--- a/src/compiler/scala/tools/nsc/transform/Erasure.scala
+++ b/src/compiler/scala/tools/nsc/transform/Erasure.scala
@@ -185,22 +185,22 @@ abstract class Erasure extends AddInterfaces
private def isErasedValueType(tpe: Type) = tpe.isInstanceOf[ErasedValueType]
- /* Drop redundant interfaces (ones which are implemented by some other parent) from the immediate parents.
+ /* Drop redundant types (ones which are implemented by some other parent) from the immediate parents.
* This is important on Android because there is otherwise an interface explosion.
*/
- def minimizeInterfaces(lstIfaces: List[Type]): List[Type] = {
- var rest = lstIfaces
- var leaves = List.empty[Type]
- while(!rest.isEmpty) {
+ def minimizeParents(parents: List[Type]): List[Type] = {
+ var rest = parents
+ var leaves = collection.mutable.ListBuffer.empty[Type]
+ while(rest.nonEmpty) {
val candidate = rest.head
val nonLeaf = leaves exists { t => t.typeSymbol isSubClass candidate.typeSymbol }
if(!nonLeaf) {
- leaves = candidate :: (leaves filterNot { t => candidate.typeSymbol isSubClass t.typeSymbol })
+ leaves = leaves filterNot { t => candidate.typeSymbol isSubClass t.typeSymbol }
+ leaves += candidate
}
rest = rest.tail
}
-
- leaves.reverse
+ leaves.toList
}
@@ -220,7 +220,7 @@ abstract class Erasure extends AddInterfaces
case _ => tps
}
- val minParents = minimizeInterfaces(parents)
+ val minParents = minimizeParents(parents)
val validParents =
if (isTraitSignature)
// java is unthrilled about seeing interfaces inherit from classes
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala b/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala
index 6339e7b07e..0b53dc37de 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/Logic.scala
@@ -122,9 +122,20 @@ trait Logic extends Debugging {
// symbols are propositions
final class Sym private[PropositionalLogic] (val variable: Var, val const: Const) extends Prop {
+
+ override def equals(other: scala.Any): Boolean = other match {
+ case that: Sym => this.variable == that.variable &&
+ this.const == that.const
+ case _ => false
+ }
+
+ override def hashCode(): Int = {
+ variable.hashCode * 41 + const.hashCode
+ }
+
private val id: Int = Sym.nextSymId
- override def toString = variable + "=" + const + "#" + id
+ override def toString = s"$variable=$const#$id"
}
object Sym {
@@ -370,9 +381,11 @@ trait Logic extends Debugging {
val EmptyModel: Model
val NoModel: Model
+ final case class Solution(model: Model, unassigned: List[Sym])
+
def findModelFor(solvable: Solvable): Model
- def findAllModelsFor(solvable: Solvable): List[Model]
+ def findAllModelsFor(solvable: Solvable): List[Solution]
}
}
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala
index c20e5dce63..34ebbc7463 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchAnalysis.scala
@@ -6,6 +6,8 @@
package scala.tools.nsc.transform.patmat
+import scala.annotation.tailrec
+import scala.collection.immutable.{IndexedSeq, Iterable}
import scala.language.postfixOps
import scala.collection.mutable
import scala.reflect.internal.util.Statistics
@@ -266,7 +268,7 @@ trait MatchApproximation extends TreeAndTypeAnalysis with ScalaLogic with MatchT
// the type of the binder passed to the first invocation
// determines the type of the tree that'll be returned for that binder as of then
final def binderToUniqueTree(b: Symbol) =
- unique(accumSubst(normalize(CODE.REF(b))), b.tpe)
+ unique(accumSubst(normalize(gen.mkAttributedStableRef(b))), b.tpe)
// note that the sequencing of operations is important: must visit in same order as match execution
// binderToUniqueTree uses the type of the first symbol that was encountered as the type for all future binders
@@ -514,8 +516,16 @@ trait MatchAnalysis extends MatchApproximation {
// find the models (under which the match fails)
val matchFailModels = findAllModelsFor(propToSolvable(matchFails))
+
val scrutVar = Var(prevBinderTree)
- val counterExamples = matchFailModels.flatMap(modelToCounterExample(scrutVar))
+ val counterExamples = {
+ matchFailModels.flatMap {
+ model =>
+ val varAssignments = expandModel(model)
+ varAssignments.flatMap(modelToCounterExample(scrutVar) _)
+ }
+ }
+
// sorting before pruning is important here in order to
// keep neg/t7020.scala stable
// since e.g. List(_, _) would cover List(1, _)
@@ -587,6 +597,8 @@ trait MatchAnalysis extends MatchApproximation {
case object WildcardExample extends CounterExample { override def toString = "_" }
case object NoExample extends CounterExample { override def toString = "??" }
+ // returns a mapping from variable to
+ // equal and notEqual symbols
def modelToVarAssignment(model: Model): Map[Var, (Seq[Const], Seq[Const])] =
model.toSeq.groupBy{f => f match {case (sym, value) => sym.variable} }.mapValues{ xs =>
val (trues, falses) = xs.partition(_._2)
@@ -600,20 +612,110 @@ trait MatchAnalysis extends MatchApproximation {
v +"(="+ v.path +": "+ v.staticTpCheckable +") "+ assignment
}.mkString("\n")
- // return constructor call when the model is a true counter example
- // (the variables don't take into account type information derived from other variables,
- // so, naively, you might try to construct a counter example like _ :: Nil(_ :: _, _ :: _),
- // since we didn't realize the tail of the outer cons was a Nil)
- def modelToCounterExample(scrutVar: Var)(model: Model): Option[CounterExample] = {
+ /**
+ * The models we get from the DPLL solver need to be mapped back to counter examples.
+ * However there's no precalculated mapping model -> counter example. Even worse,
+ * not every valid model corresponds to a valid counter example.
+ * The reason is that restricting the valid models further would for example require
+ * a quadratic number of additional clauses. So to keep the optimistic case fast
+ * (i.e., all cases are covered in a pattern match), the infeasible counter examples
+ * are filtered later.
+ *
+ * The DPLL procedure keeps the literals that do not contribute to the solution
+ * unassigned, e.g., for `(a \/ b)`
+ * only {a = true} or {b = true} is required and the other variable can have any value.
+ *
+ * This function does a smart expansion of the model and avoids models that
+ * have conflicting mappings.
+ *
+ * For example for in case of the given set of symbols (taken from `t7020.scala`):
+ * "V2=2#16"
+ * "V2=6#19"
+ * "V2=5#18"
+ * "V2=4#17"
+ * "V2=7#20"
+ *
+ * One possibility would be to group the symbols by domain but
+ * this would only work for equality tests and would not be compatible
+ * with type tests.
+ * Another observation leads to a much simpler algorithm:
+ * Only one of these symbols can be set to true,
+ * since `V2` can at most be equal to one of {2,6,5,4,7}.
+ */
+ def expandModel(solution: Solution): List[Map[Var, (Seq[Const], Seq[Const])]] = {
+
+ val model = solution.model
+
// x1 = ...
// x1.hd = ...
// x1.tl = ...
// x1.hd.hd = ...
// ...
val varAssignment = modelToVarAssignment(model)
+ debug.patmat("var assignment for model " + model + ":\n" + varAssignmentString(varAssignment))
+
+ // group symbols that assign values to the same variables (i.e., symbols are mutually exclusive)
+ // (thus the groups are sets of disjoint assignments to variables)
+ val groupedByVar: Map[Var, List[Sym]] = solution.unassigned.groupBy(_.variable)
+
+ val expanded = for {
+ (variable, syms) <- groupedByVar.toList
+ } yield {
+
+ val (equal, notEqual) = varAssignment.getOrElse(variable, Nil -> Nil)
+
+ def addVarAssignment(equalTo: List[Const], notEqualTo: List[Const]) = {
+ Map(variable ->(equal ++ equalTo, notEqual ++ notEqualTo))
+ }
+
+ // this assignment is needed in case that
+ // there exists already an assign
+ val allNotEqual = addVarAssignment(Nil, syms.map(_.const))
- debug.patmat("var assignment for model "+ model +":\n"+ varAssignmentString(varAssignment))
+ // this assignment is conflicting on purpose:
+ // a list counter example could contain wildcards: e.g. `List(_,_)`
+ val allEqual = addVarAssignment(syms.map(_.const), Nil)
+ if(equal.isEmpty) {
+ val oneHot = for {
+ s <- syms
+ } yield {
+ addVarAssignment(List(s.const), syms.filterNot(_ == s).map(_.const))
+ }
+ allEqual :: allNotEqual :: oneHot
+ } else {
+ allEqual :: allNotEqual :: Nil
+ }
+ }
+
+ if (expanded.isEmpty) {
+ List(varAssignment)
+ } else {
+ // we need the cartesian product here,
+ // since we want to report all missing cases
+ // (i.e., combinations)
+ val cartesianProd = expanded.reduceLeft((xs, ys) =>
+ for {map1 <- xs
+ map2 <- ys} yield {
+ map1 ++ map2
+ })
+
+ // add expanded variables
+ // note that we can just use `++`
+ // since the Maps have disjoint keySets
+ for {
+ m <- cartesianProd
+ } yield {
+ varAssignment ++ m
+ }
+ }
+ }
+
+ // return constructor call when the model is a true counter example
+ // (the variables don't take into account type information derived from other variables,
+ // so, naively, you might try to construct a counter example like _ :: Nil(_ :: _, _ :: _),
+ // since we didn't realize the tail of the outer cons was a Nil)
+ def modelToCounterExample(scrutVar: Var)(varAssignment: Map[Var, (Seq[Const], Seq[Const])]): Option[CounterExample] = {
// chop a path into a list of symbols
def chop(path: Tree): List[Symbol] = path match {
case Ident(_) => List(path.symbol)
@@ -742,7 +844,7 @@ trait MatchAnalysis extends MatchApproximation {
// then we can safely ignore these counter examples since we will eventually encounter
// both counter examples separately
case _ if inSameDomain => None
-
+
// not a valid counter-example, possibly since we have a definite type but there was a field mismatch
// TODO: improve reasoning -- in the mean time, a false negative is better than an annoying false positive
case _ => Some(NoExample)
@@ -761,12 +863,12 @@ trait MatchAnalysis extends MatchApproximation {
}
def analyzeCases(prevBinder: Symbol, cases: List[List[TreeMaker]], pt: Type, suppression: Suppression): Unit = {
- if (!suppression.unreachable) {
+ if (!suppression.suppressUnreachable) {
unreachableCase(prevBinder, cases, pt) foreach { caseIndex =>
reportUnreachable(cases(caseIndex).last.pos)
}
}
- if (!suppression.exhaustive) {
+ if (!suppression.suppressExhaustive) {
val counterExamples = exhaustive(prevBinder, cases, pt)
if (counterExamples.nonEmpty)
reportMissingCases(prevBinder.pos, counterExamples)
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala
index e8c75ed1ee..6302e34ac9 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchTranslation.scala
@@ -208,7 +208,7 @@ trait MatchTranslation {
case _ => (cases, None)
}
- checkMatchVariablePatterns(nonSyntheticCases)
+ if (!settings.XnoPatmatAnalysis) checkMatchVariablePatterns(nonSyntheticCases)
// we don't transform after uncurry
// (that would require more sophistication when generating trees,
@@ -248,7 +248,10 @@ trait MatchTranslation {
if (caseDefs forall treeInfo.isCatchCase) caseDefs
else {
val swatches = { // switch-catches
- val bindersAndCases = caseDefs map { caseDef =>
+ // SI-7459 must duplicate here as we haven't commited to switch emission, and just figuring out
+ // if we can ends up mutating `caseDefs` down in the use of `substituteSymbols` in
+ // `TypedSubstitution#Substitution`. That is called indirectly by `emitTypeSwitch`.
+ val bindersAndCases = caseDefs.map(_.duplicate) map { caseDef =>
// generate a fresh symbol for each case, hoping we'll end up emitting a type-switch (we don't have a global scrut there)
// if we fail to emit a fine-grained switch, have to do translateCase again with a single scrutSym (TODO: uniformize substitution on treemakers so we can avoid this)
val caseScrutSym = freshSym(pos, pureType(ThrowableTpe))
@@ -518,7 +521,7 @@ trait MatchTranslation {
// reference the (i-1)th case accessor if it exists, otherwise the (i-1)th tuple component
override protected def tupleSel(binder: Symbol)(i: Int): Tree = {
val accessors = binder.caseFieldAccessors
- if (accessors isDefinedAt (i-1)) REF(binder) DOT accessors(i-1)
+ if (accessors isDefinedAt (i-1)) gen.mkAttributedStableRef(binder) DOT accessors(i-1)
else codegen.tupleSel(binder)(i) // this won't type check for case classes, as they do not inherit ProductN
}
}
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala b/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala
index 6755e3726f..b703b5bc6d 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/MatchTreeMaking.scala
@@ -21,9 +21,10 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging {
import global._
import definitions._
- final case class Suppression(exhaustive: Boolean, unreachable: Boolean)
+ final case class Suppression(suppressExhaustive: Boolean, suppressUnreachable: Boolean)
object Suppression {
val NoSuppression = Suppression(false, false)
+ val FullSuppression = Suppression(true, true)
}
///////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -166,8 +167,17 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging {
val usedBinders = new mutable.HashSet[Symbol]()
// all potentially stored subpat binders
val potentiallyStoredBinders = stored.unzip._1.toSet
+ def ref(sym: Symbol) =
+ if (potentiallyStoredBinders(sym)) usedBinders += sym
// compute intersection of all symbols in the tree `in` and all potentially stored subpat binders
- in.foreach(t => if (potentiallyStoredBinders(t.symbol)) usedBinders += t.symbol)
+ in.foreach {
+ case tt: TypeTree =>
+ tt.tpe foreach { // SI-7459 e.g. case Prod(t) => new t.u.Foo
+ case SingleType(_, sym) => ref(sym)
+ case _ =>
+ }
+ case t => ref(t.symbol)
+ }
if (usedBinders.isEmpty) in
else {
@@ -542,7 +552,7 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging {
debug.patmat("combining cases: "+ (casesNoSubstOnly.map(_.mkString(" >> ")).mkString("{", "\n", "}")))
val (suppression, requireSwitch): (Suppression, Boolean) =
- if (settings.XnoPatmatAnalysis) (Suppression.NoSuppression, false)
+ if (settings.XnoPatmatAnalysis) (Suppression.FullSuppression, false)
else scrut match {
case Typed(tree, tpt) =>
val suppressExhaustive = tpt.tpe hasAnnotation UncheckedClass
@@ -574,7 +584,7 @@ trait MatchTreeMaking extends MatchCodeGen with Debugging {
(Suppression.NoSuppression, false)
}
- emitSwitch(scrut, scrutSym, casesNoSubstOnly, pt, matchFailGenOverride, suppression.exhaustive).getOrElse{
+ emitSwitch(scrut, scrutSym, casesNoSubstOnly, pt, matchFailGenOverride, unchecked = suppression.suppressExhaustive).getOrElse{
if (requireSwitch) reporter.warning(scrut.pos, "could not emit switch for @switch annotated match")
if (casesNoSubstOnly nonEmpty) {
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala b/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala
index ef50e083a1..d35aad964d 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/PatternMatching.scala
@@ -12,7 +12,7 @@ import scala.language.postfixOps
import scala.tools.nsc.transform.TypingTransformers
import scala.tools.nsc.transform.Transform
import scala.reflect.internal.util.Statistics
-import scala.reflect.internal.Types
+import scala.reflect.internal.{Mode, Types}
import scala.reflect.internal.util.Position
/** Translate pattern matching.
@@ -198,33 +198,57 @@ trait Interface extends ast.TreeDSL {
}
class Substitution(val from: List[Symbol], val to: List[Tree]) {
- import global.{Transformer, Ident, NoType}
+ import global.{Transformer, Ident, NoType, TypeTree, SingleType}
// We must explicitly type the trees that we replace inside some other tree, since the latter may already have been typed,
// and will thus not be retyped. This means we might end up with untyped subtrees inside bigger, typed trees.
def apply(tree: Tree): Tree = {
// according to -Ystatistics 10% of translateMatch's time is spent in this method...
// since about half of the typedSubst's end up being no-ops, the check below shaves off 5% of the time spent in typedSubst
- if (!tree.exists { case i@Ident(_) => from contains i.symbol case _ => false}) tree
- else (new Transformer {
+ val toIdents = to.forall(_.isInstanceOf[Ident])
+ val containsSym = tree.exists {
+ case i@Ident(_) => from contains i.symbol
+ case tt: TypeTree => tt.tpe.exists {
+ case SingleType(_, sym) =>
+ (from contains sym) && {
+ if (!toIdents) global.devWarning(s"Unexpected substitution of non-Ident into TypeTree `$tt`, subst= $this")
+ true
+ }
+ case _ => false
+ }
+ case _ => false
+ }
+ val toSyms = to.map(_.symbol)
+ object substIdentsForTrees extends Transformer {
private def typedIfOrigTyped(to: Tree, origTp: Type): Tree =
if (origTp == null || origTp == NoType) to
// important: only type when actually substing and when original tree was typed
// (don't need to use origTp as the expected type, though, and can't always do this anyway due to unknown type params stemming from polymorphic extractors)
else typer.typed(to)
+ def typedStable(t: Tree) = typer.typed(t.shallowDuplicate, Mode.MonoQualifierModes | Mode.TYPEPATmode)
+ lazy val toTypes: List[Type] = to map (tree => typedStable(tree).tpe)
+
override def transform(tree: Tree): Tree = {
def subst(from: List[Symbol], to: List[Tree]): Tree =
if (from.isEmpty) tree
- else if (tree.symbol == from.head) typedIfOrigTyped(to.head.shallowDuplicate.setPos(tree.pos), tree.tpe)
+ else if (tree.symbol == from.head) typedIfOrigTyped(typedStable(to.head).setPos(tree.pos), tree.tpe)
else subst(from.tail, to.tail)
- tree match {
+ val tree1 = tree match {
case Ident(_) => subst(from, to)
case _ => super.transform(tree)
}
+ tree1.modifyType(_.substituteTypes(from, toTypes))
}
- }).transform(tree)
+ }
+ if (containsSym) {
+ if (to.forall(_.isInstanceOf[Ident]))
+ tree.duplicate.substituteSymbols(from, to.map(_.symbol)) // SI-7459 catches `case t => new t.Foo`
+ else
+ substIdentsForTrees.transform(tree)
+ }
+ else tree
}
diff --git a/src/compiler/scala/tools/nsc/transform/patmat/Solving.scala b/src/compiler/scala/tools/nsc/transform/patmat/Solving.scala
index 1ba13c0617..27217f0dc2 100644
--- a/src/compiler/scala/tools/nsc/transform/patmat/Solving.scala
+++ b/src/compiler/scala/tools/nsc/transform/patmat/Solving.scala
@@ -288,7 +288,7 @@ trait Solving extends Logic {
val NoTseitinModel: TseitinModel = null
// returns all solutions, if any (TODO: better infinite recursion backstop -- detect fixpoint??)
- def findAllModelsFor(solvable: Solvable): List[Model] = {
+ def findAllModelsFor(solvable: Solvable): List[Solution] = {
debug.patmat("find all models for\n"+ cnfString(solvable.cnf))
// we must take all vars from non simplified formula
@@ -305,54 +305,12 @@ trait Solving extends Logic {
relevantLits.map(lit => -lit)
}
- /**
- * The DPLL procedure only returns a minimal mapping from literal to value
- * such that the CNF formula is satisfied.
- * E.g. for:
- * `(a \/ b)`
- * The DPLL procedure will find either {a = true} or {b = true}
- * as solution.
- *
- * The expansion step will amend both solutions with the unassigned variable
- * i.e., {a = true} will be expanded to {a = true, b = true} and {a = true, b = false}.
- */
- def expandUnassigned(unassigned: List[Int], model: TseitinModel): List[TseitinModel] = {
- // the number of solutions is doubled for every unassigned variable
- val expandedModels = 1 << unassigned.size
- var current = mutable.ArrayBuffer[TseitinModel]()
- var next = mutable.ArrayBuffer[TseitinModel]()
- current.sizeHint(expandedModels)
- next.sizeHint(expandedModels)
-
- current += model
-
- // we use double buffering:
- // read from `current` and create a two models for each model in `next`
- for {
- s <- unassigned
- } {
- for {
- model <- current
- } {
- def force(l: Lit) = model + l
-
- next += force(Lit(s))
- next += force(Lit(-s))
- }
-
- val tmp = current
- current = next
- next = tmp
-
- next.clear()
- }
-
- current.toList
+ final case class TseitinSolution(model: TseitinModel, unassigned: List[Int]) {
+ def projectToSolution(symForVar: Map[Int, Sym]) = Solution(projectToModel(model, symForVar), unassigned map symForVar)
}
-
def findAllModels(clauses: Array[Clause],
- models: List[TseitinModel],
- recursionDepthAllowed: Int = global.settings.YpatmatExhaustdepth.value): List[TseitinModel]=
+ models: List[TseitinSolution],
+ recursionDepthAllowed: Int = global.settings.YpatmatExhaustdepth.value): List[TseitinSolution]=
if (recursionDepthAllowed == 0) {
val maxDPLLdepth = global.settings.YpatmatExhaustdepth.value
reportWarning("(Exhaustivity analysis reached max recursion depth, not all missing cases are reported. " +
@@ -368,17 +326,15 @@ trait Solving extends Logic {
val unassigned: List[Int] = (relevantVars -- model.map(lit => lit.variable)).toList
debug.patmat("unassigned "+ unassigned +" in "+ model)
- val forced = expandUnassigned(unassigned, model)
- debug.patmat("forced "+ forced)
+ val solution = TseitinSolution(model, unassigned)
val negated = negateModel(model)
- findAllModels(clauses :+ negated, forced ++ models, recursionDepthAllowed - 1)
+ findAllModels(clauses :+ negated, solution :: models, recursionDepthAllowed - 1)
}
else models
}
- val tseitinModels: List[TseitinModel] = findAllModels(solvable.cnf, Nil)
- val models: List[Model] = tseitinModels.map(projectToModel(_, solvable.symbolMapping.symForVar))
- models
+ val tseitinSolutions = findAllModels(solvable.cnf, Nil)
+ tseitinSolutions.map(_.projectToSolution(solvable.symbolMapping.symForVar))
}
private def withLit(res: TseitinModel, l: Lit): TseitinModel = {
diff --git a/src/compiler/scala/tools/nsc/typechecker/Typers.scala b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
index bc879eefcf..e6fa9a0142 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Typers.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Typers.scala
@@ -3281,6 +3281,22 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper
}
handleOverloaded
+ case _ if isPolymorphicSignature(fun.symbol) =>
+ // Mimic's Java's treatment of polymorphic signatures as described in
+ // https://docs.oracle.com/javase/specs/jls/se8/html/jls-15.html#jls-15.12.3
+ //
+ // One can think of these methods as being infinitely overloaded. We create
+ // a ficticious new cloned method symbol for each call site that takes on a signature
+ // governed by a) the argument types and b) the expected type
+ val args1 = typedArgs(args, forArgMode(fun, mode))
+ val pts = args1.map(_.tpe.deconst)
+ val clone = fun.symbol.cloneSymbol
+ val cloneParams = pts map (pt => clone.newValueParameter(currentUnit.freshTermName()).setInfo(pt))
+ val resultType = if (isFullyDefined(pt)) pt else ObjectTpe
+ clone.modifyInfo(mt => copyMethodType(mt, cloneParams, resultType))
+ val fun1 = fun.setSymbol(clone).setType(clone.info)
+ doTypedApply(tree, fun1, args1, mode, resultType).setType(resultType)
+
case mt @ MethodType(params, _) =>
val paramTypes = mt.paramTypes
// repeat vararg as often as needed, remove by-name
@@ -3776,8 +3792,12 @@ trait Typers extends Adaptations with Tags with TypersTracking with PatternTyper
case TypeRef(pre, sym, args) =>
if (sym.isAliasType && containsLocal(tp) && (tp.dealias ne tp)) apply(tp.dealias)
else {
- if (pre.isVolatile)
- InferTypeWithVolatileTypeSelectionError(tree, pre)
+ if (pre.isVolatile) pre match {
+ case SingleType(_, sym) if sym.isSynthetic && isPastTyper =>
+ debuglog(s"ignoring volatility of prefix in pattern matcher generated inferred type: $tp") // See pos/t7459c.scala
+ case _ =>
+ InferTypeWithVolatileTypeSelectionError(tree, pre)
+ }
mapOver(tp)
}
case _ =>