Eliminating duplication in zero creation.

paulp · paulp · commit fbb7865e137e · 2012-02-20T21:59:06.000-08:00
diff --git a/src/compiler/scala/reflect/internal/TreeGen.scala b/src/compiler/scala/reflect/internal/TreeGen.scala
@@ -250,20 +250,19 @@ abstract class TreeGen {
    *    var x: T = _
    *  which is appropriate to the given Type.
    */
-  def mkZero(tp: Type): Tree = {
-    val tree = tp.typeSymbol match {
-      case UnitClass    => Literal(Constant())
-      case BooleanClass => Literal(Constant(false))
-      case FloatClass   => Literal(Constant(0.0f))
-      case DoubleClass  => Literal(Constant(0.0d))
-      case ByteClass    => Literal(Constant(0.toByte))
-      case ShortClass   => Literal(Constant(0.toShort))
-      case IntClass     => Literal(Constant(0))
-      case LongClass    => Literal(Constant(0L))
-      case CharClass    => Literal(Constant(0.toChar))
-      case _            => Literal(Constant(null))
-    }
-    tree setType tp
+  def mkZero(tp: Type): Tree = Literal(mkConstantZero(tp)) setType tp
+
+  def mkConstantZero(tp: Type): Constant = tp.typeSymbol match {
+    case UnitClass    => Constant(())
+    case BooleanClass => Constant(false)
+    case FloatClass   => Constant(0.0f)
+    case DoubleClass  => Constant(0.0d)
+    case ByteClass    => Constant(0.toByte)
+    case ShortClass   => Constant(0.toShort)
+    case IntClass     => Constant(0)
+    case LongClass    => Constant(0L)
+    case CharClass    => Constant(0.toChar)
+    case _            => Constant(null)
   }
 
   def mkZeroContravariantAfterTyper(tp: Type): Tree = {
diff --git a/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala b/src/compiler/scala/tools/nsc/backend/icode/GenICode.scala
@@ -879,23 +879,19 @@ abstract class GenICode extends SubComponent  {
           } else if (sym.elisionLevel.exists (_ < settings.elidebelow.value || settings.noassertions.value)) {
             // XXX settings.noassertions.value temporarily retained to avoid
             // breakage until a reasonable interface is settled upon.
-            debuglog("Eliding call from " + tree.symbol.owner + " to " + sym + " based on its elision threshold of " + sym.elisionLevel.get)
-            val value = expectedType match {
-              case UNIT => ()
-              case BOOL => false
-              case BYTE => 0:Byte
-              case SHORT => 0:Short
-              case CHAR => '?'
-              case INT => 0
-              case LONG => 0L
-              case FLOAT => 0.0f
-              case DOUBLE => 0.0
-              case _ => null
+            debuglog("Eliding call from " + tree.symbol.owner + " to " + sym + 
+              " based on its elision threshold of " + sym.elisionLevel.get)
+            if (expectedType.isValueType) {
+              ctx.bb.emit(CONSTANT(global.gen.mkConstantZero(expectedType.toType)), tree.pos)
+              generatedType = expectedType
+            }
+            else {
+              ctx.bb.emit(CONSTANT(Constant(null)), tree.pos)
+              generatedType = NullReference
             }
-            ctx.bb.emit(CONSTANT(Constant(value)), tree.pos)
-            generatedType = if (expectedType.isInstanceOf[ValueTypeKind]) expectedType else NullReference
             ctx
-          } else {  // normal method call
+          }
+          else {  // normal method call
             debuglog("Gen CALL_METHOD with sym: " + sym + " isStaticSymbol: " + sym.isStaticMember);
             val invokeStyle =
               if (sym.isStaticMember)
diff --git a/test/files/run/elidable.check b/test/files/run/elidable.check
@@ -6,7 +6,7 @@ Good for me, I was not elided. C.f2
 false
 0
 0
-?
+0
 0
 0
 0.0
diff --git a/test/files/run/elidable.scala b/test/files/run/elidable.scala
@@ -59,7 +59,7 @@ object Test {
     println(f6())
     println(f7())
     println(f8())
-    println(f9())
+    println(f9().toInt)
     println(fa())
     println(fb())
     println(fc())

Original file line number	Diff line number	Diff line change
`@@ -6,7 +6,7 @@ Good for me, I was not elided. C.f2`
`6`	`6`	`false`
`7`	`7`	`0`
`8`	`8`	`0`
`9`		`-?`
	`9`	`+0`
`10`	`10`	`0`
`11`	`11`	`0`
`12`	`12`	`0.0`