small opts, fixed #1270, if target is Literal, ...

small opts, fixed #1270, if target is Literal, generate Literal instead
of jump (no sharing)

3 files changed, 28 insertions, 12 deletions

diff --git a/src/compiler/scala/tools/nsc/matching/CodeFactory.scala b/src/compiler/scala/tools/nsc/matching/CodeFactory.scala
index b037f20551..ce19ae5446 100644
--- a/src/compiler/scala/tools/nsc/matching/CodeFactory.scala
+++ b/src/compiler/scala/tools/nsc/matching/CodeFactory.scala
@@ -23,7 +23,13 @@ trait CodeFactory {
   import posAssigner.atPos         // for filling in tree positions
 
 
-  final def typedValDef(x:Symbol, rhs:Tree) = typed{ValDef(x, typed(rhs,x.tpe))}
+  final def typedValDef(x:Symbol, rhs:Tree) = {
+    //Console.println("1"+x.tpe)
+    x.tpe match {
+      case WildcardType => rhs.setType(null); val rhs1 = typed(rhs); x setInfo rhs1.tpe; typed{ValDef(x, rhs)}
+      case _ => typed{ValDef(x, typed(rhs, x.tpe))}
+    }
+  }
 
   final def mk_(tpe:Type) = Ident(nme.WILDCARD) setType tpe
 
@@ -81,7 +87,7 @@ trait CodeFactory {
     var result = defaultBody
     var i = condition.length - 1
     while (i >= 0) {
-      result = If(condition(i), body(i), result)
+      result = makeIf(condition(i), body(i), result)
       i -= 1
     }
     result
@@ -107,9 +113,10 @@ trait CodeFactory {
       Not(Select(Ident(vsym), nme.isEmpty))
   }
 
-  final def makeIf(cond: Tree, thenp: Tree, elsep: Tree) = cond match {
-    case Literal(Constant(true)) => thenp
-    case Literal(Constant(false)) => elsep
+  final def makeIf(cond: Tree, thenp: Tree, elsep: Tree) = (cond,thenp,elsep) match {
+    case (Literal(Constant(true)),  _, _) => thenp
+    case (Literal(Constant(false)), _, _) => elsep
+    case (_, Literal(Constant(true)), Literal(Constant(false))) => cond
     case _ => If(cond, thenp, elsep)
   }
 
diff --git a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
index af1d2dfca4..0485a0d959 100644
--- a/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
+++ b/src/compiler/scala/tools/nsc/matching/ParallelMatching.scala
@@ -499,7 +499,7 @@ trait ParallelMatching  {
       val succ = repToTree(srep, handleOuter)
       val fail = repToTree(frep, handleOuter)
       try {
-        typed{ If(cond2, succ, fail) }
+        typed{ makeIf(cond2, succ, fail) }
       } catch {
         case e =>
           Console.println("failed to type-check If")
@@ -815,17 +815,19 @@ object Rep {
         }
       }
       val body  = targets(bx)
-      val label = theOwner.newLabel(body.pos, "body%"+bx).setInfo(new MethodType(argts.toList, resultType/*body.tpe*/))
+      // bug: typer is not able to digest a body of type Nothing being assigned result type Unit
+      val tpe = if(body.tpe.typeSymbol eq definitions.AllClass) body.tpe else resultType
+      val label = theOwner.newLabel(body.pos, "body%"+bx).setInfo(new MethodType(argts.toList, tpe))
       //Console.println("label.tpe"+label.tpe)
 
       labels(bx) = label
 
-      if(body.isInstanceOf[Throw]) {
-        return squeezedBlock(vdefs.reverse, body.duplicate setType resultType)
+      if(body.isInstanceOf[Throw] || body.isInstanceOf[Literal]) {
+        return squeezedBlock(vdefs.reverse, body.duplicate setType tpe)
       }
       //Console.println("- !isReached returning LabelDef "+label)
       //Console.println("- !      and vdefs "+vdefs)
-      return Block(vdefs, LabelDef(label, vrev.reverse, body setType resultType))
+      return squeezedBlock(vdefs, LabelDef(label, vrev.reverse, body setType tpe))
     }
 
     //Console.println("-  isReached before, jump to "+labels(bx))
@@ -851,7 +853,8 @@ object Rep {
           }
         }
     }
-    if(targets(bx).isInstanceOf[Throw]) {
+    val body = targets(bx)
+    if(body.isInstanceOf[Throw] || body.isInstanceOf[Literal]) {
       val vdefs = new ListBuffer[Tree]
       val it = vss(bx).elements; while(it.hasNext) {
         val v = it.next
@@ -860,7 +863,7 @@ object Rep {
           vdefs  += typedValDef(v, substv)
         }
       }
-      return squeezedBlock(vdefs.toList, targets(bx).duplicate setType resultType)
+      return squeezedBlock(vdefs.toList, body.duplicate setType resultType)
     }
 
 
diff --git a/src/compiler/scala/tools/nsc/matching/PatternMatchers.scala b/src/compiler/scala/tools/nsc/matching/PatternMatchers.scala
index 5538799b5e..8b44b773ad 100644
--- a/src/compiler/scala/tools/nsc/matching/PatternMatchers.scala
+++ b/src/compiler/scala/tools/nsc/matching/PatternMatchers.scala
@@ -133,6 +133,11 @@ trait PatternMatchers { self: transform.ExplicitOuter with PatternNodes with Par
           case null => // ignore
             return
 
+          case a:AssertionError =>
+            cunit.error(cases.head.pos, "assertion failed while compiling this case")
+            a.printStackTrace()
+            throw FatalError("died in parallel match algorithm" )
+
           case _:AbstractMethodError =>
             cunit.error(cases.head.pos, "please recompile matcher component (explicitouter,patternmattcher, parallelmatching,codefactory)")
             throw FatalError("died in parallel match algorithm" )
@@ -255,6 +260,7 @@ trait PatternMatchers { self: transform.ExplicitOuter with PatternNodes with Par
              //Console.println(app.symbol)
              //Console.println(fn.symbol)
              if(!xs.isEmpty) {
+               assert(false)
                return CantHandleApply // System.exit(-1); // this should never happen
              }
              null