abstract class TailCalls extends SubComponent with Transform
Perform tail recursive call elimination.
- Source
- TailCalls.scala
- Version
1.0
- Alphabetic
- By Inheritance
- TailCalls
- Transform
- SubComponent
- AnyRef
- Any
- by any2stringadd
- by StringFormat
- by Ensuring
- by ArrowAssoc
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Instance Constructors
- new TailCalls()
Type Members
- abstract class StdPhase extends GlobalPhase
A standard phase template
A standard phase template
- Definition Classes
- SubComponent
- class Phase extends StdPhase
The phase defined by this transform
- class TailCallElimination extends Global.Transformer
A Tail Call Transformer
A Tail Call Transformer
- 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.
- class TailPosLabelsTraverser extends Global.Traverser
Abstract Value Members
- abstract val global: Global
The global environment; overridden by instantiation in Global.
The global environment; overridden by instantiation in Global.
- Definition Classes
- SubComponent
- abstract val runsAfter: List[String]
Names of phases that must run before this phase.
Names of phases that must run before this phase.
- Definition Classes
- SubComponent
- abstract val runsRightAfter: Option[String]
Name of the phase that this phase must follow immediately.
Name of the phase that this phase must follow immediately.
- Definition Classes
- SubComponent
Concrete Value Members
- final def !=(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def ##(): Int
- Definition Classes
- AnyRef → Any
- def +(other: String): String
- def ->[B](y: B): (TailCalls, B)
- final def ==(arg0: Any): Boolean
- Definition Classes
- AnyRef → Any
- final def afterOwnPhase[T](op: => T): T
- Definition Classes
- SubComponent
- Annotations
- @inline()
- final def asInstanceOf[T0]: T0
- Definition Classes
- Any
- final def beforeOwnPhase[T](op: => T): T
- Definition Classes
- SubComponent
- Annotations
- @inline()
- def clone(): AnyRef
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.CloneNotSupportedException]) @native()
- def enabled: Boolean
Is this component enabled? Default is true.
Is this component enabled? Default is true.
- Definition Classes
- SubComponent
- def ensuring(cond: (TailCalls) => Boolean, msg: => Any): TailCalls
- def ensuring(cond: (TailCalls) => Boolean): TailCalls
- def ensuring(cond: Boolean, msg: => Any): TailCalls
- def ensuring(cond: Boolean): TailCalls
- final def eq(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def equals(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef → Any
- def finalize(): Unit
- Attributes
- protected[java.lang]
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.Throwable])
- def formatted(fmtstr: String): String
- final def getClass(): Class[_ <: AnyRef]
- Definition Classes
- AnyRef → Any
- Annotations
- @native()
- 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
- val initial: Boolean
True if this phase runs before all other phases.
True if this phase runs before all other phases. Usually,
parser
.- Definition Classes
- SubComponent
- val internal: Boolean
True if this phase is not provided by a plug-in.
True if this phase is not provided by a plug-in.
- Definition Classes
- SubComponent
- final def isInstanceOf[T0]: Boolean
- Definition Classes
- Any
- final def ne(arg0: AnyRef): Boolean
- Definition Classes
- AnyRef
- def newPhase(prev: nsc.Phase): StdPhase
Create a new phase which applies transformer
Create a new phase which applies transformer
- Definition Classes
- TailCalls → Transform → SubComponent
- def newTransformer(unit: Global.CompilationUnit): Global.Transformer
The transformer factory
- final def notify(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- final def notifyAll(): Unit
- Definition Classes
- AnyRef
- Annotations
- @native()
- 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
- val phaseName: String
The name of the phase
The name of the phase
- Definition Classes
- TailCalls → SubComponent
- def phaseNewFlags: Long
New flags defined by the phase which are not valid before
New flags defined by the phase which are not valid before
- Definition Classes
- SubComponent
- 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
- val requires: List[String]
Names of phases required by this component.
Names of phases required by this component. Default is
Nil
.- Definition Classes
- SubComponent
- val runsBefore: List[String]
Names of phases that must run after this phase.
Names of phases that must run after this phase. Default is
Nil
.- Definition Classes
- SubComponent
- final def synchronized[T0](arg0: => T0): T0
- Definition Classes
- AnyRef
- val terminal: Boolean
True if this phase runs after all other phases.
True if this phase runs after all other phases. Usually,
terminal
.- Definition Classes
- SubComponent
- def toString(): String
- Definition Classes
- AnyRef → Any
- final def wait(): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long, arg1: Int): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException])
- final def wait(arg0: Long): Unit
- Definition Classes
- AnyRef
- Annotations
- @throws(classOf[java.lang.InterruptedException]) @native()
Deprecated Value Members
- def →[B](y: B): (TailCalls, B)
- Implicit
- This member is added by an implicit conversion from TailCalls toArrowAssoc[TailCalls] performed by method ArrowAssoc in scala.Predef.
- Definition Classes
- ArrowAssoc
- Annotations
- @deprecated
- Deprecated
(Since version 2.13.0) Use
->
instead. If you still wish to display it as one character, consider using a font with programming ligatures such as Fira Code.
The Scala compiler and reflection APIs.