scala.tools.nsc.transform

# SpecializeTypes

#### abstract class SpecializeTypes extends SubComponent with InfoTransform with TypingTransformers

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.

Linear Supertypes
TypingTransformers, InfoTransform, Transform, SubComponent, AnyRef, Any
Known Subclasses
specializeTypes
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2. By inheritance

Inherited

1. SpecializeTypes
2. TypingTransformers
3. InfoTransform
4. Transform
5. SubComponent
6. AnyRef
7. Any

Implicitly

1. by any2stringadd
2. by any2stringfmt
3. by any2ArrowAssoc
4. by any2Ensuring

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### Instance Constructors

1. #### new SpecializeTypes()

### Type Members

1. #### case class Abstract (t: Global.Symbol) extends SpecializedInfo with Product with Serializable

   Symbol is a specialized abstract method, either specialized or original.

2. #### class Duplicator extends Duplicators

   This duplicator additionally performs casts of expressions if that is allowed by the `casts` map.

3. #### case class Forward (t: Global.Symbol) extends SpecializedInfo with Product with Serializable

   Symbol is a method that should be forwarded to 't'

4. #### case class Implementation (target: Global.Symbol) extends SpecializedInfo with Product with Serializable

   Symbol is a specialized method whose body should be the target's method body.

5. #### class ImplementationAdapter extends Global.TreeSymSubstituter

   A tree symbol substituter that substitutes on type skolems.

6. #### case class NormalizedMember (target: Global.Symbol) extends SpecializedInfo with Product with Serializable

   Symbol is a normalized member obtained by specializing 'target'.

7. #### case class Overload (sym: Global.Symbol, env: TypeEnv) extends Product with Serializable

8. #### class Phase extends InfoTransform.Phase

   The phase defined by this transform

9. #### case class SpecialOverload (original: Global.Symbol, env: TypeEnv) extends SpecializedInfo with Product with Serializable

   Symbol is a special overloaded method of 'original', in the environment env.

10. #### case class SpecialOverride (target: Global.Symbol) extends SpecializedInfo with Product with Serializable

    Symbol is a specialized override paired with `target`.

11. #### class SpecializationDuplicator extends Duplicator

    Introduced to fix SI-7343: Phase ordering problem between Duplicators and Specialization.

12. #### class SpecializationPhase extends Phase

13. #### class SpecializationTransformer extends Global.Transformer

14. #### case class SpecializedAccessor (target: Global.Symbol) extends SpecializedInfo with Product with Serializable

    Symbol is a specialized accessor for the `target` field.

15. #### abstract class SpecializedInfo extends AnyRef

16. #### case class SpecializedInnerClass (target: Global.Symbol, env: TypeEnv) extends SpecializedInfo with Product with Serializable

    A specialized inner class that specializes original inner class `target` on a type parameter of the enclosing class, in the typeenv `env`.

17. #### abstract class StdPhase extends GlobalPhase

    A standard phase template

18. #### type TypeEnv = Map[Global.Symbol, Global.Type]

19. #### abstract class TypingTransformer extends Global.Transformer

    Definition Classes
      TypingTransformers

### Abstract Value Members

1. #### abstract val global: Global

   Definition Classes
     TypingTransformers

2. #### abstract val runsAfter: List[String]

   List of phase names, this phase should run after

   List of phase names, this phase should run after

   Definition Classes
     SubComponent

3. #### abstract val runsRightAfter: Option[String]

   Phase name this phase will attach itself to, not allowing any phase to come between it and the phase name declared

   Phase name this phase will attach itself to, not allowing any phase to come between it and the phase name declared

   Definition Classes
     SubComponent

### Concrete Value Members

1. #### final def !=(arg0: AnyRef): Boolean

   Definition Classes
     AnyRef

2. #### final def !=(arg0: Any): Boolean

   Definition Classes
     Any

3. #### final def ##(): Int

   Definition Classes
     AnyRef → Any

4. #### def +(other: String): String

   Implicit information
     This member is added by an implicit conversion from SpecializeTypes to StringAdd performed by method any2stringadd in scala.Predef.
   Definition Classes
     StringAdd

5. #### def ->[B](y: B): (SpecializeTypes, B)

   Implicit information
     This member is added by an implicit conversion from SpecializeTypes to ArrowAssoc[SpecializeTypes] performed by method any2ArrowAssoc in scala.Predef.
   Definition Classes
     ArrowAssoc
   Annotations
     @inline()

6. #### final def ==(arg0: AnyRef): Boolean

   Definition Classes
     AnyRef

7. #### final def ==(arg0: Any): Boolean

   Definition Classes
     Any

8. #### object TypeEnv

9. #### object UnifyError extends Throwable with ControlThrowable with Product with Serializable

10. #### def addConcreteSpecMethod(m: Global.Symbol): Unit

    Add method m to the set of symbols for which we need an implementation tree in the tree transformer.

    Add method m to the set of symbols for which we need an implementation tree in the tree transformer.

    Note

      This field is part of the specializeTypes subcomponent, so any symbols that here are not garbage collected at the end of a compiler run!

11. #### final def afterOwnPhase[T](op: ⇒ T): T

    Definition Classes
      SubComponent
    Annotations
      @inline()

12. #### final def asInstanceOf[T0]: T0

    Definition Classes
      Any

13. #### final def beforeOwnPhase[T](op: ⇒ T): T

    Definition Classes
      SubComponent
    Annotations
      @inline()

14. #### def changesBaseClasses: Boolean

    This phase changes base classes.

    This phase changes base classes.

    Definition Classes
      SpecializeTypes → InfoTransform

15. #### def clone(): AnyRef

    Attributes
      protected[java.lang]
    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

16. #### def concreteTypes(sym: Global.Symbol): List[Global.Type]

    Return the types `sym` should be specialized at.

    Return the types `sym` should be specialized at. This may be some of the primitive types or AnyRef. AnyRef means that a new type parameter T will be generated later, known to be a subtype of AnyRef (T <: AnyRef). These are in a meaningful order for stability purposes.

17. #### def conflicting(env: TypeEnv): Boolean

    Is any type variable in `env` conflicting with any if its type bounds, when type bindings in `env` are taken into account?

    Is any type variable in `env` conflicting with any if its type bounds, when type bindings in `env` are taken into account?

    A conflicting type environment could still be satisfiable.

18. #### def emptyEnv: TypeEnv

19. #### def ensuring(cond: (SpecializeTypes) ⇒ Boolean, msg: ⇒ Any): SpecializeTypes

    Implicit information
      This member is added by an implicit conversion from SpecializeTypes to Ensuring[SpecializeTypes] performed by method any2Ensuring in scala.Predef.
    Definition Classes
      Ensuring

20. #### def ensuring(cond: (SpecializeTypes) ⇒ Boolean): SpecializeTypes

    Implicit information
      This member is added by an implicit conversion from SpecializeTypes to Ensuring[SpecializeTypes] performed by method any2Ensuring in scala.Predef.
    Definition Classes
      Ensuring

21. #### def ensuring(cond: Boolean, msg: ⇒ Any): SpecializeTypes

    Implicit information
      This member is added by an implicit conversion from SpecializeTypes to Ensuring[SpecializeTypes] performed by method any2Ensuring in scala.Predef.
    Definition Classes
      Ensuring

22. #### def ensuring(cond: Boolean): SpecializeTypes

    Implicit information
      This member is added by an implicit conversion from SpecializeTypes to Ensuring[SpecializeTypes] performed by method any2Ensuring in scala.Predef.
    Definition Classes
      Ensuring

23. #### final def eq(arg0: AnyRef): Boolean

    Definition Classes
      AnyRef

24. #### def equals(arg0: Any): Boolean

    Definition Classes
      AnyRef → Any

25. #### def finalize(): Unit

    Attributes
      protected[java.lang]
    Definition Classes
      AnyRef
    Annotations
      @throws( classOf[java.lang.Throwable] )

26. #### def formatted(fmtstr: String): String

    Implicit information
      This member is added by an implicit conversion from SpecializeTypes to StringFormat performed by method any2stringfmt in scala.Predef.
    Definition Classes
      StringFormat
    Annotations
      @inline()

27. #### def genericClass(sClass: Global.Symbol): Global.Symbol

    Returns the generic class that was specialized to 'sClass', or 'sClass' itself if sClass is not a specialized subclass.

28. #### final def getClass(): Class[_]

    Definition Classes
      AnyRef → Any

29. #### def hasSpecializedParams(clazz: Global.Symbol): Boolean

    Has `clazz` any type parameters that need be specialized?

30. #### def hashCode(): Int

    SubComponent are added to a HashSet and two phases are the same if they have the same name

    SubComponent are added to a HashSet and two phases are the same if they have the same name

    Definition Classes
      SubComponent → AnyRef → Any

31. #### def illegalSpecializedInheritance(clazz: Global.Symbol): Boolean

32. #### val internal: Boolean

    Internal flag to tell external from internal phases

    Internal flag to tell external from internal phases

    Definition Classes
      SubComponent

33. #### final def isInstanceOf[T0]: Boolean

    Definition Classes
      Any

34. #### def isNormalizedMember(m: Global.Symbol): Boolean

35. #### def keepsTypeParams: Boolean

    Definition Classes
      SpecializeTypes → InfoTransform

36. #### final def ne(arg0: AnyRef): Boolean

    Definition Classes
      AnyRef

37. #### def newPhase(prev: nsc.Phase): StdPhase

    Just to mark uncheckable

    Just to mark uncheckable

    Definition Classes
      SpecializeTypes → InfoTransform → Transform → SubComponent

38. #### def newTransformer(unit: Global.CompilationUnit): Global.Transformer

    The transformer factory

    The transformer factory

    Attributes
      protected
    Definition Classes
      SpecializeTypes → Transform

39. #### def nonConflicting(env: TypeEnv): Boolean

40. #### final def notify(): Unit

    Definition Classes
      AnyRef

41. #### final def notifyAll(): Unit

    Definition Classes
      AnyRef

42. #### def originalClass(clazz: Global.Symbol): Global.Symbol

    Return the generic class corresponding to this specialized class.

43. #### def ownPhase: nsc.Phase

    The phase corresponding to this subcomponent in the current compiler run

    The phase corresponding to this subcomponent in the current compiler run

    Definition Classes
      SubComponent

44. #### val phaseName: String

    the name of the phase:

    the name of the phase:

    Definition Classes
      SpecializeTypes → SubComponent

45. #### def phaseNewFlags: Long

    The following flags may be set by this phase:

    The following flags may be set by this phase:

    Definition Classes
      SpecializeTypes → SubComponent

46. #### def phaseNextFlags: Long

    New flags defined by the phase which are not valid until immediately after it

    New flags defined by the phase which are not valid until immediately after it

    Definition Classes
      SubComponent

47. #### def printSpecStats(): Unit

48. #### def produceTypeParameters(syms: List[Global.Symbol], nowner: Global.Symbol, env: TypeEnv): collection.immutable.List[Global.Symbol]

    Produces the symbols from type parameters `syms` of the original owner, in the given type environment `env`.

    Produces the symbols from type parameters `syms` of the original owner, in the given type environment `env`. The new owner is `nowner`.

    Non-specialized type parameters are cloned into new ones. Type parameters specialized on AnyRef have preexisting symbols.

    For instance, a @specialized(AnyRef) T, will become T$sp <: AnyRef.

49. #### val runsBefore: List[String]

    List of phase names, this phase should run before

    List of phase names, this phase should run before

    Definition Classes
      SubComponent

50. #### def satisfiabilityConstraints(env: TypeEnv): Option[TypeEnv]

51. #### def satisfiable(env: TypeEnv, warnings: Boolean): Boolean

52. #### def satisfiable(env: TypeEnv): Boolean

    The type environment is sound w.

    The type environment is sound w.r.t. to all type bounds or only soft conflicts appear. An environment is sound if all bindings are within the bounds of the given type variable. A soft conflict is a binding that does not fall within the bounds, but whose bounds contain type variables that are @specialized, (that could become satisfiable).

53. #### lazy val specializableTypes: collection.immutable.List[Global.Type]

54. #### def specializeCalls(unit: Global.CompilationUnit): TypingTransformer { ... /* 7 definitions in type refinement */ }

55. #### def specializeClass(clazz: Global.Symbol, outerEnv: TypeEnv): List[Global.Symbol]

    Specialize 'clazz', in the environment `outerEnv`.

    Specialize 'clazz', in the environment `outerEnv`. The outer environment contains bindings for specialized types of enclosing classes.

    A class C is specialized w.r.t to its own specialized type params `stps`, by specializing its members, and creating a new class for each combination of `stps`.

56. #### val specializedClass: HashMap[(Global.Symbol, TypeEnv), Global.Symbol]

    For a given class and concrete type arguments, give its specialized class

57. #### def specializedParams(sym: Global.Symbol): List[Global.Symbol]

    Return specialized type parameters.

58. #### val specializedType: Global.TypeMap

59. #### def specializedTypeVars(tpe: Global.Type): Set[Global.Symbol]

    Return the set of @specialized type variables mentioned by the given type.

    Return the set of @specialized type variables mentioned by the given type. It only counts type variables that appear:

    - naked
    - as arguments to type constructors in @specialized positions (arrays are considered as Array[@specialized T])

60. #### def specializedTypeVars(sym: Global.Symbol): Set[Global.Symbol]

61. #### def specializedTypeVars(tpes: List[Global.Type]): Set[Global.Symbol]

62. #### def specializesClass(sym: Global.Symbol): Global.Symbol

    If the symbol is the companion of a value class, the value class.

    If the symbol is the companion of a value class, the value class. Otherwise, AnyRef.

63. #### def splitParams(tps: List[Global.Symbol]): (collection.immutable.List[Global.Symbol], collection.immutable.List[Global.Symbol])

64. #### def survivingArgs(sym: Global.Symbol, args: List[Global.Type]): List[Global.Type]

    Given an original class symbol and a list of types its type parameters are instantiated at returns a list of type parameters that should remain in the TypeRef when instantiating a specialized type.

65. #### def survivingParams(params: List[Global.Symbol], env: TypeEnv): collection.immutable.List[Global.Symbol]

    Type parameters that survive when specializing in the specified environment.

66. #### final def synchronized[T0](arg0: ⇒ T0): T0

    Definition Classes
      AnyRef

67. #### def toString(): String

    Definition Classes
      AnyRef → Any

68. #### def transformInfo(sym: Global.Symbol, tpe: Global.Type): Global.Type

    Type transformation.

    Type transformation. It is applied to all symbols, compiled or loaded. If it is a 'no-specialization' run, it is applied only to loaded symbols.

    Definition Classes
      SpecializeTypes → InfoTransform

69. #### final def wait(): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

70. #### final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

71. #### final def wait(arg0: Long): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

72. #### def →[B](y: B): (SpecializeTypes, B)

    Implicit information
      This member is added by an implicit conversion from SpecializeTypes to ArrowAssoc[SpecializeTypes] performed by method any2ArrowAssoc in scala.Predef.
    Definition Classes
      ArrowAssoc

### Shadowed Implicit Value Members

1. #### val self: Any

   Implicit information
     This member is added by an implicit conversion from SpecializeTypes to StringAdd performed by method any2stringadd in scala.Predef.
   Shadowing
     This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
     To access this member you can use a type ascription:

         (specializeTypes: StringAdd).self

   Definition Classes
     StringAdd

2. #### val self: Any

   Implicit information
     This member is added by an implicit conversion from SpecializeTypes to StringFormat performed by method any2stringfmt in scala.Predef.
   Shadowing
     This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
     To access this member you can use a type ascription:

         (specializeTypes: StringFormat).self

   Definition Classes
     StringFormat

### Deprecated Value Members

1. #### def x: SpecializeTypes

   Implicit information
     This member is added by an implicit conversion from SpecializeTypes to ArrowAssoc[SpecializeTypes] performed by method any2ArrowAssoc in scala.Predef.
   Shadowing
     This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
     To access this member you can use a type ascription:

         (specializeTypes: ArrowAssoc[SpecializeTypes]).x

   Definition Classes
     ArrowAssoc
   Annotations
     @deprecated
   Deprecated

     (Since version 2.10.0) Use `leftOfArrow`instead``

2. #### def x: SpecializeTypes

   Implicit information
     This member is added by an implicit conversion from SpecializeTypes to Ensuring[SpecializeTypes] performed by method any2Ensuring in scala.Predef.
   Shadowing
     This implicitly inherited member is ambiguous. One or more implicitly inherited members have similar signatures, so calling this member may produce an ambiguous implicit conversion compiler error.
     To access this member you can use a type ascription:

         (specializeTypes: Ensuring[SpecializeTypes]).x

   Definition Classes
     Ensuring
   Annotations
     @deprecated
   Deprecated

     (Since version 2.10.0) Use `resultOfEnsuring`instead``

### Inherited from TypingTransformers

### Inherited from InfoTransform

### Inherited from Transform

### Inherited from SubComponent

### Inherited from AnyRef

### Inherited from Any

### Inherited by implicit conversion any2stringadd from SpecializeTypes to StringAdd

### Inherited by implicit conversion any2stringfmt from SpecializeTypes to StringFormat

### Inherited by implicit conversion any2ArrowAssoc from SpecializeTypes to ArrowAssoc[SpecializeTypes]

### Inherited by implicit conversion any2Ensuring from SpecializeTypes to Ensuring[SpecializeTypes]

### Ungrouped