Eliminate needless Options.

Many of our core types have dedicated sentinels which serve
perfectly to communicate "no value", even more perfectly than
None. Saving a billion allocations is gravy.

1 files changed, 7 insertions, 8 deletions

diff --git a/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala b/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
index fb927d15d3..fa7279f6ef 100644
--- a/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
+++ b/src/compiler/scala/tools/nsc/symtab/classfile/ClassfileParser.scala
@@ -39,7 +39,7 @@ abstract class ClassfileParser {
   protected var isScala: Boolean = _        // does class file describe a scala class?
   protected var isScalaAnnot: Boolean = _   // does class file describe a scala class with its pickled info in an annotation?
   protected var isScalaRaw: Boolean = _     // this class file is a scala class with no pickled info
-  protected var busy: Option[Symbol] = None // lock to detect recursive reads
+  protected var busy: Symbol = _            // lock to detect recursive reads
   protected var currentClass: Name = _      // JVM name of the current class
   protected var classTParams = Map[Name,Symbol]()
   protected var srcfile0 : Option[AbstractFile] = None
@@ -90,16 +90,15 @@ abstract class ClassfileParser {
     case e: RuntimeException        => handleError(e)
   }
   @inline private def pushBusy[T](sym: Symbol)(body: => T): T = {
-    busy match {
-      case Some(`sym`)  => throw new IOException(s"unsatisfiable cyclic dependency in '$sym'")
-      case Some(sym1)   => throw new IOException(s"illegal class file dependency between '$sym' and '$sym1'")
-      case _            => ()
-    }
+    if (busy eq sym)
+      throw new IOException(s"unsatisfiable cyclic dependency in '$sym'")
+    else if ((busy ne null) && (busy ne NoSymbol))
+      throw new IOException(s"illegal class file dependency between '$sym' and '$busy'")
 
-    busy = Some(sym)
+    busy = sym
     try body
     catch parseErrorHandler
-    finally busy = None
+    finally busy = NoSymbol
   }
   @inline private def raiseLoaderLevel[T](body: => T): T = {
     loaders.parentsLevel += 1