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 TailCalls extends SubComponent with Transform

    Perform tail recursive call elimination.

    Perform tail recursive call elimination.

    Definition Classes
    transform
    Version

    1.0

  • class TailCallElimination extends Global.Transformer

    A Tail Call Transformer

    A Tail Call Transformer

    Definition Classes
    TailCalls
    Version

    1.1 What it does: Finds method calls in tail-position and replaces them with jumps. A call is in a tail-position if it is the last instruction to be executed in the body of a method. This is done by recursing over the trees that may contain calls in tail-position (trees that can't contain such calls are not transformed). However, they are not that many. Self-recursive calls in tail-position are replaced by jumps to a label at the beginning of the method. As the JVM provides no way to jump from a method to another one, non-recursive calls in tail-position are not optimized. A method call is self-recursive if it calls the current method and the method is final (otherwise, it could be a call to an overridden method in a subclass). Furthermore, if the method has @specialized annotated type parameters, the recursive call must contain these parameters as type arguments. Recursive calls on a different instance are optimized. Since 'this' is not a local variable, a dummy local val is added and used as a label parameter. The backend knows to load the corresponding argument in the 'this' (local at index 0). This dummy local is never used and should be cleaned up by dead code elimination (when enabled). This phase has been moved before pattern matching to catch more of the common cases of tail recursive functions. This means that more cases should be taken into account (like nested function, and pattern cases). If a method contains self-recursive calls, a label is added to at the beginning of its body and the calls are replaced by jumps to that label. Assumes: Uncurry has been run already, and no multiple parameter lists exist.

  • ClonedTailContext
  • DefDefTailContext
  • EmptyTailContext
  • TailContext

sealed trait TailContext extends AnyRef

Source
TailCalls.scala
Linear Supertypes
AnyRef, Any
Known Subclasses
ClonedTailContext, DefDefTailContext, EmptyTailContext
Ordering
  1. Alphabetic
  2. By Inheritance
Inherited
  1. TailContext
  2. AnyRef
  3. Any
Implicitly
  1. by any2stringadd
  2. by StringFormat
  3. by Ensuring
  4. by ArrowAssoc
  1. Hide All
  2. Show All
Visibility
  1. Public
  2. All

Abstract Value Members

  1. abstract def label: Global.Symbol
  2. abstract def method: Global.Symbol
  3. abstract def methodPos: Global.Position
  4. abstract def tailLabels: Set[Global.Symbol]
  5. abstract def tailPos: Boolean
  6. abstract def tparams: List[Global.Symbol]

Concrete Value Members

  1. final def !=(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  2. final def ##(): Int
    Definition Classes
    AnyRef → Any
  3. def +(other: String): String
    Implicit
    This member is added by an implicit conversion from TailContext to any2stringadd[TailContext] performed by method any2stringadd in scala.Predef.
    Definition Classes
    any2stringadd
  4. def ->[B](y: B): (TailContext, B)
    Implicit
    This member is added by an implicit conversion from TailContext to ArrowAssoc[TailContext] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc
    Annotations
    @inline()
  5. final def ==(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  6. final def asInstanceOf[T0]: T0
    Definition Classes
    Any
  7. def clone(): AnyRef
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  8. def clonedTailContext(tailPos: Boolean): TailContext
    Attributes
    protected
  9. def enclosingType: Global.Type
  10. def ensuring(cond: (TailContext) ⇒ Boolean, msg: ⇒ Any): TailContext
    Implicit
    This member is added by an implicit conversion from TailContext to Ensuring[TailContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  11. def ensuring(cond: (TailContext) ⇒ Boolean): TailContext
    Implicit
    This member is added by an implicit conversion from TailContext to Ensuring[TailContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  12. def ensuring(cond: Boolean, msg: ⇒ Any): TailContext
    Implicit
    This member is added by an implicit conversion from TailContext to Ensuring[TailContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  13. def ensuring(cond: Boolean): TailContext
    Implicit
    This member is added by an implicit conversion from TailContext to Ensuring[TailContext] performed by method Ensuring in scala.Predef.
    Definition Classes
    Ensuring
  14. final def eq(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  15. def equals(arg0: Any): Boolean
    Definition Classes
    AnyRef → Any
  16. def finalize(): Unit
    Attributes
    protected[lang]
    Definition Classes
    AnyRef
    Annotations
    @throws( classOf[java.lang.Throwable] )
  17. final def getClass(): Class[_]
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  18. def hashCode(): Int
    Definition Classes
    AnyRef → Any
    Annotations
    @native()
  19. def isEligible: Boolean
  20. final def isInstanceOf[T0]: Boolean
    Definition Classes
    Any
  21. def isMandatory: Boolean
  22. def isTransformed: Boolean
  23. final def ne(arg0: AnyRef): Boolean
    Definition Classes
    AnyRef
  24. def newThis(pos: Global.Position): Global.TermSymbol
  25. final def noTailContext(): TailContext
  26. final def notify(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  27. final def notifyAll(): Unit
    Definition Classes
    AnyRef
    Annotations
    @native()
  28. final def synchronized[T0](arg0: ⇒ T0): T0
    Definition Classes
    AnyRef
  29. def toString(): String
    Definition Classes
    TailContext → AnyRef → Any
  30. final def wait(): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  31. final def wait(arg0: Long, arg1: Int): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... )
  32. final def wait(arg0: Long): Unit
    Definition Classes
    AnyRef
    Annotations
    @throws( ... ) @native()
  33. final def yesTailContext(): TailContext
  34. def →[B](y: B): (TailContext, B)
    Implicit
    This member is added by an implicit conversion from TailContext to ArrowAssoc[TailContext] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
    ArrowAssoc

Deprecated Value Members

  1. def formatted(fmtstr: String): String
    Implicit
    This member is added by an implicit conversion from TailContext to StringFormat[TailContext] performed by method StringFormat in scala.Predef.
    Definition Classes
    StringFormat
    Annotations
    @deprecated @inline()
    Deprecated

    (Since version 2.12.16) Use formatString.format(value) instead of value.formatted(formatString), or use the f"" string interpolator. In Java 15 and later, formatted resolves to the new method in String which has reversed parameters.

Inherited from AnyRef

Inherited from Any

Inherited by implicit conversion any2stringadd from TailContext to any2stringadd[TailContext]

Inherited by implicit conversion StringFormat from TailContext to StringFormat[TailContext]

Inherited by implicit conversion Ensuring from TailContext to Ensuring[TailContext]

Inherited by implicit conversion ArrowAssoc from TailContext to ArrowAssoc[TailContext]

Ungrouped