Packages

•  package root

  The Scala compiler and reflection APIs.

  The Scala compiler and reflection APIs.

  Definition Classes

  root

•  package scala

  Definition Classes

  root

•  package tools

  Definition Classes

  scala

•  package nsc

  Definition Classes

  tools

•  package transform

  Definition Classes

  nsc

•  abstract class SpecializeTypes extends SubComponent with InfoTransform with TypingTransformers

  Specialize code on types.

  Specialize code on types.

  Make sure you've read the thesis:

  Iulian Dragos: Compiling Scala for Performance (chapter 4)

  There are some things worth noting, (possibly) not mentioned there: 0) Make sure you understand the meaning of various SpecializedInfo descriptors defined below.

  1) Specializing traits by introducing bridges in specialized methods of the specialized trait may introduce problems during mixin composition. Concretely, it may cause cyclic calls and result in a stack overflow. See ticket #4351. This was solved by introducing an Abstract specialized info descriptor. Instead of generating a bridge in the trait, an abstract method is generated.

  2) Specialized private members sometimes have to be switched to protected. In some cases, even this is not enough. Example:

  class A[@specialized T](protected val d: T) {
    def foo(that: A[T]) = that.d
  }

  Specialization will generate a specialized class and a specialized method:

  class A$mcI$sp(protected val d: Int) extends A[Int] {
    def foo(that: A[Int]) = foo$mcI$sp(that)
    def foo(that: A[Int]) = that.d
  }

  Above, A$mcI$sp cannot access d, so the method cannot be typechecked.

  Definition Classes

  transform

•  class SpecializationTransformer extends TypingTransformer

  Definition Classes

  SpecializeTypes

• CollectMethodBodies

scala.tools.nsc.transform.SpecializeTypes.SpecializationTransformer

CollectMethodBodies