Devirtualize Type.exists

OlivierBlanvillain · OlivierBlanvillain · commit bb7c2daadcde · 2018-08-03T11:10:25.000+02:00
diff --git a/compiler/src/dotty/tools/dotc/core/Types.scala b/compiler/src/dotty/tools/dotc/core/Types.scala
@@ -134,7 +134,7 @@ object Types {
     }
 
     /** Is this type different from NoType? */
-    def exists: Boolean = true
+    final def exists: Boolean = this.ne(NoType)
 
     /** This type, if it exists, otherwise `that` type */
     def orElse(that: => Type) = if (exists) this else that
@@ -3766,7 +3766,6 @@ object Types {
 
   /** Sentinel for "missing type" */
   @sharable case object NoType extends CachedGroundType {
-    override def exists = false
     override def computeHash(bs: Binders) = hashSeed
   }
 

Original file line number	Diff line number	Diff line change
`@@ -134,7 +134,7 @@ object Types {`
`134`	`134`	`}`
`135`	`135`
`136`	`136`	`/** Is this type different from NoType? */`
`137`		`- def exists: Boolean = true`
	`137`	`+ final def exists: Boolean = this.ne(NoType)`
`138`	`138`
`139`	`139`	/** This type, if it exists, otherwise `that` type */
`140`	`140`	`def orElse(that: => Type) = if (exists) this else that`
`@@ -3766,7 +3766,6 @@ object Types {`
`3766`	`3766`
`3767`	`3767`	`/** Sentinel for "missing type" */`
`3768`	`3768`	`@sharable case object NoType extends CachedGroundType {`
`3769`		`- override def exists = false`
`3770`	`3769`	`override def computeHash(bs: Binders) = hashSeed`
`3771`	`3770`	`}`
`3772`	`3771`