Short/Byte/Char/Int scrutinees will now be comp...

Short/Byte/Char/Int scrutinees will now be compiled into switches if all
cases are literals. (There remain many things which can prevent switch
creation.)

4 files changed, 7 insertions, 5 deletions

diff --git a/src/compiler/scala/tools/nsc/ast/TreeDSL.scala b/src/compiler/scala/tools/nsc/ast/TreeDSL.scala
index 3922e3fd40..1866fee719 100644
--- a/src/compiler/scala/tools/nsc/ast/TreeDSL.scala
+++ b/src/compiler/scala/tools/nsc/ast/TreeDSL.scala
@@ -43,7 +43,7 @@ trait TreeDSL {
       if (f isDefinedAt x) Some(f(x)) else None
 
     // Applies a function to a value and then returns the value.
-    def applyAndReturn[T](f: T => Unit)(x: T): T = { f(x) ; x }
+    def returning[T](f: T => Unit)(x: T): T = { f(x) ; x }
 
     // strip bindings to find what lies beneath
     final def unbind(x: Tree): Tree = x match {
diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index 941777c030..f0ef7b215b 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -170,7 +170,7 @@ trait ParallelMatching extends ast.TreeDSL {
         }
       }
 
-      applyAndReturn[Tree](resetTraverser traverse _)(lxtt transform tree)
+      returning[Tree](resetTraverser traverse _)(lxtt transform tree)
     }
 
     final def isReached(bx: Int)        = labels contains bx
@@ -366,7 +366,7 @@ trait ParallelMatching extends ast.TreeDSL {
 
       // tests
       def isDefined = sym ne NoSymbol
-      def isSimple  = tpe.isChar || tpe.isInt
+      def isSimple  = tpe.isByte || tpe.isShort || tpe.isChar || tpe.isInt
 
       // sequences
       def seqType   = tpe.widen baseType SeqClass
diff --git a/src/compiler/scala/tools/nsc/matching/PatternNodes.scala b/src/compiler/scala/tools/nsc/matching/PatternNodes.scala
index 45b63463e9..1278f417e5 100644
--- a/src/compiler/scala/tools/nsc/matching/PatternNodes.scala
+++ b/src/compiler/scala/tools/nsc/matching/PatternNodes.scala
@@ -93,6 +93,8 @@ trait PatternNodes extends ast.TreeDSL
 
       // These tests for final classes can inspect the typeSymbol
       private def is(s: Symbol) = tpe.typeSymbol eq s
+      def      isByte = is(ByteClass)
+      def     isShort = is(ShortClass)
       def       isInt = is(IntClass)
       def      isChar = is(CharClass)
       def   isBoolean = is(BooleanClass)
diff --git a/src/compiler/scala/tools/nsc/typechecker/Unapplies.scala b/src/compiler/scala/tools/nsc/typechecker/Unapplies.scala
index 7944e940ef..b586298560 100644
--- a/src/compiler/scala/tools/nsc/typechecker/Unapplies.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/Unapplies.scala
@@ -94,10 +94,10 @@ trait Unapplies extends ast.TreeDSL
   }
 
   def copyUntyped[T <: Tree](tree: T): T =
-    applyAndReturn[T](UnTyper traverse _)(tree.duplicate)
+    returning[T](UnTyper traverse _)(tree.duplicate)
 
   def copyUntypedInvariant(td: TypeDef): TypeDef =
-    applyAndReturn[TypeDef](UnTyper traverse _)(
+    returning[TypeDef](UnTyper traverse _)(
       treeCopy.TypeDef(td, td.mods &~ (COVARIANT | CONTRAVARIANT), td.name,
                        td.tparams, td.rhs).duplicate
     )