scala.tools.nsc.backend.icode.BasicBlocks

# BasicBlock

###
Related Doc: package BasicBlocks

#### class BasicBlock extends ProgramPoint[ICodes.BasicBlock]

This class represents a basic block. Each basic block contains a list of instructions that are either executed all, or none. No jumps to/from the "middle" of the basic block are allowed (modulo exceptions).

Self Type
  ICodes.BasicBlock
Source
  BasicBlocks.scala

Linear Supertypes
ProgramPoint[ICodes.BasicBlock], AnyRef, Any
Known Subclasses
NoBasicBlock
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Inherited

1. BasicBlock
2. ProgramPoint
3. AnyRef
4. Any

Implicitly

1. by any2stringadd
2. by StringFormat
3. by Ensuring
4. by ArrowAssoc

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### Instance Constructors

1. #### new BasicBlock(label: Int, method: ICodes.IMethod)

### Value Members

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

   Test two objects for inequality.

   Test two objects for inequality.

   returns

     `true` if !(this == that), false otherwise.

   Definition Classes
     AnyRef → Any

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

   Equivalent to `x.hashCode` except for boxed numeric types and `null`.

   Equivalent to `x.hashCode` except for boxed numeric types and `null`. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For `null` returns a hashcode where `null.hashCode` throws a `NullPointerException`.

   returns

     a hash value consistent with ==

   Definition Classes
     AnyRef → Any

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

   Implicit information
     This member is added by an implicit conversion from ICodes.BasicBlock to any2stringadd[ICodes.BasicBlock] performed by method any2stringadd in scala.Predef.
   Definition Classes
     any2stringadd

4. #### def ->[B](y: B): (ICodes.BasicBlock, B)

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

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

   The expression `x == that` is equivalent to `if (x eq null) that eq null else x.equals(that)`.

   The expression `x == that` is equivalent to `if (x eq null) that eq null else x.equals(that)`.

   arg0

     the object to compare against this object for equality.

   returns

     `true` if the receiver object is equivalent to the argument; `false` otherwise.

   Definition Classes
     AnyRef → Any

6. #### def apply(n: Int): ICodes.Instruction

   Return the n-th instruction.

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

   Cast the receiver object to be of type `T0`.

   Cast the receiver object to be of type `T0`.

   Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression `1.asInstanceOf[String]` will throw a `ClassCastException` at runtime, while the expression `List(1).asInstanceOf[List[String]]` will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

   returns

     the receiver object.

   Definition Classes
     Any
   Exceptions thrown

     `ClassCastException` if the receiver object is not an instance of the erasure of type `T0`.

8. #### def blockContents: String

9. #### def clear(): Unit

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

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the `clone` method is platform dependent.

    returns

      a copy of the receiver object.

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

      not specified by SLS as a member of AnyRef

11. #### def close(): Unit

    Close the block

12. #### def closeWith(instr: ICodes.Instruction, pos: Global.Position): Unit

13. #### def closeWith(instr: ICodes.Instruction): Unit

    do nothing if block is already closed

14. #### def closed: Boolean

    Is this block closed?

15. #### def closed_=(b: Boolean): Unit

16. #### def code: ICodes.Code

17. #### def directSuccessors: List[ICodes.BasicBlock]

18. #### def emit(is: Seq[ICodes.Instruction]): Unit

19. #### def emit(instr: ICodes.Instruction, pos: Global.Position): Unit

    Emitting does not set touched to true.

    Emitting does not set touched to true. During code generation this is a hotspot and setting the flag for each emit is a waste. Caching should happen only after a block is closed, which sets the DIRTYSUCCS flag.

20. #### def emit(instr: ICodes.Instruction): Unit

    Add a new instruction at the end of the block, using the same source position as the last emitted instruction

21. #### def emitOnly(is: ICodes.Instruction*): Unit

    The semantics of this are a little odd but it's designed to work seamlessly with the existing code.

    The semantics of this are a little odd but it's designed to work seamlessly with the existing code. It emits each supplied instruction, then closes the block. The odd part is that if the instruction has pos == NoPosition, it calls the 1-arg emit, but otherwise it calls the 2-arg emit. This way I could retain existing behavior exactly by calling setPos on any instruction using the two arg version which I wanted to include in a call to emitOnly.

22. #### def ensuring(cond: (ICodes.BasicBlock) ⇒ Boolean, msg: ⇒ Any): ICodes.BasicBlock

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

23. #### def ensuring(cond: (ICodes.BasicBlock) ⇒ Boolean): ICodes.BasicBlock

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

24. #### def ensuring(cond: Boolean, msg: ⇒ Any): ICodes.BasicBlock

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

25. #### def ensuring(cond: Boolean): ICodes.BasicBlock

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

26. #### def enterIgnoreMode(): Unit

    Enter ignore mode: new 'emit'ted instructions will not be added to this basic block.

    Enter ignore mode: new 'emit'ted instructions will not be added to this basic block. It makes the generation of THROW and RETURNs easier.

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

    Tests whether the argument (`arg0`) is a reference to the receiver object (`this`).

    Tests whether the argument (`arg0`) is a reference to the receiver object (`this`).

    The `eq` method implements an equivalence relation on non-null instances of `AnyRef`, and has three additional properties:

    - It is consistent: for any non-null instances `x` and `y` of type `AnyRef`, multiple invocations of `x.eq(y)` consistently returns `true` or consistently returns `false`.
    - For any non-null instance `x` of type `AnyRef`, `x.eq(null)` and `null.eq(x)` returns `false`.
    - `null.eq(null)` returns `true`.

    When overriding the `equals` or `hashCode` methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (`o1 eq o2`), they should be equal to each other (`o1 == o2`) and they should hash to the same value (`o1.hashCode == o2.hashCode`).

    returns

      `true` if the argument is a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef

28. #### def equals(other: Any): Boolean

    The equality method for reference types.

    The equality method for reference types. Default implementation delegates to `eq`.

    See also `equals` in scala.Any.

    returns

      `true` if the receiver object is equivalent to the argument; `false` otherwise.

    Definition Classes
      BasicBlock → AnyRef → Any

29. #### def exceptionHandlerStart: Boolean

    Is this block the start block of an exception handler?

    Is this block the start block of an exception handler?

    Definition Classes
      BasicBlock → ProgramPoint

30. #### def exceptionHandlerStart_=(b: Boolean): Unit

31. #### def exceptionSuccessors: List[ICodes.BasicBlock]

32. #### def exceptionSuccessorsForBlock(block: ICodes.BasicBlock): List[ICodes.BasicBlock]

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

    Called by the garbage collector on the receiver object when there are no more references to the object.

    Called by the garbage collector on the receiver object when there are no more references to the object.

    The details of when and if the `finalize` method is invoked, as well as the interaction between `finalize` and non-local returns and exceptions, are all platform dependent.

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

      not specified by SLS as a member of AnyRef

34. #### def flagsString: String

35. #### final def foreach[U](f: (ICodes.Instruction) ⇒ U): Unit

    Apply a function to all the instructions of the block.

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

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

37. #### def fromList(is: List[ICodes.Instruction]): Unit

38. #### def fullString: String

39. #### def getArray: Array[ICodes.Instruction]

    return the underlying array of instructions

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

    A representation that corresponds to the dynamic class of the receiver object.

    A representation that corresponds to the dynamic class of the receiver object.

    The nature of the representation is platform dependent.

    returns

      a representation that corresponds to the dynamic class of the receiver object.

    Definition Classes
      AnyRef → Any
    Note

      not specified by SLS as a member of AnyRef

41. #### def hasFlag(flag: Int): Boolean

    Does this block have the given flag?

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

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in scala.Any.

    returns

      the hash code value for this object.

    Definition Classes
      BasicBlock → AnyRef → Any

43. #### def ignore: Boolean

    When set, the `emit` methods will be ignored.

44. #### def ignore_=(b: Boolean): Unit

45. #### def indexOf(inst: ICodes.Instruction): Int

    Return the index of inst.

    Return the index of inst. Uses reference equality. Returns -1 if not found.

46. #### final def isEmpty: Boolean

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

    Test whether the dynamic type of the receiver object is `T0`.

    Test whether the dynamic type of the receiver object is `T0`.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression `1.isInstanceOf[String]` will return `false`, while the expression `List(1).isInstanceOf[List[String]]` will return `true`. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

      `true` if the receiver object is an instance of erasure of type `T0`; `false` otherwise.

    Definition Classes
      Any

48. #### def iterator: Iterator[ICodes.Instruction]

    Return an iterator over the instructions in this basic block.

49. #### def killIf(cond: Boolean): Unit

    if cond is true, closes this block, entersIgnoreMode, and removes the block from its list of blocks.

    if cond is true, closes this block, entersIgnoreMode, and removes the block from its list of blocks. Used to allow a block to be started and then cancelled when it is discovered to be unreachable.

50. #### def killUnless(cond: Boolean): Unit

    Same as killIf but with the logic of the condition reversed

51. #### val label: Int

52. #### def lastInstruction: ICodes.Instruction

    Return the last instruction of this basic block.

53. #### def length: Int

    The number of instructions in this basic block so far.

54. #### def loopHeader: Boolean

    Is this block the head of a while?

55. #### def loopHeader_=(b: Boolean): Unit

56. #### val method: ICodes.IMethod

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

    Equivalent to `!(this eq that)`.

    Equivalent to `!(this eq that)`.

    returns

      `true` if the argument is not a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef

58. #### final def nonEmpty: Boolean

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

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

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

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

61. #### def open(): Unit

62. #### def predContents: String

63. #### def predecessors: List[ICodes.BasicBlock]

    Returns the predecessors of this block.

    Returns the predecessors of this block.

    Definition Classes
      BasicBlock → ProgramPoint

64. #### var preds: List[ICodes.BasicBlock]

    Cached predecessors.

65. #### def removeInstructionsAt(positions: Int*): Unit

    Removes instructions found at the given positions.

66. #### def removeLastInstruction(): Unit

    Remove the last instruction of this basic block.

    Remove the last instruction of this basic block. It is fast for an open block, but slower when the block is closed.

67. #### def replaceInstruction(oldInstr: ICodes.Instruction, is: List[ICodes.Instruction]): Boolean

    Replaces `oldInstr` with `is`.

    Replaces `oldInstr` with `is`. It does not update the position field in the newly inserted instructions, so it behaves differently than the one-instruction versions of this function.

68. #### def replaceInstruction(oldInstr: ICodes.Instruction, newInstr: ICodes.Instruction): Boolean

    Replace the given instruction with the new one.

    Replace the given instruction with the new one. Returns `true` if it actually changed something. The replacing instruction is given the nsc.util.Position of the instruction it replaces.

69. #### def replaceInstruction(pos: Int, instr: ICodes.Instruction): Boolean

    Replace the instruction at the given position.

    Replace the instruction at the given position. Used by labels when they are anchored. The replacing instruction is given the nsc.util.Position of the instruction it replaces.

70. #### def size: Int

71. #### def subst(map: Map[ICodes.Instruction, ICodes.Instruction]): Unit

    Replaces all instructions found in the map.

72. #### def succContents: String

73. #### def successors: List[ICodes.BasicBlock]

    Definition Classes
      BasicBlock → ProgramPoint

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

    Definition Classes
      AnyRef

75. #### def take(n: Int): Seq[ICodes.Instruction]

76. #### def toList: List[ICodes.Instruction]

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

    Creates a String representation of this object.

    Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.

    returns

      a String representation of the object.

    Definition Classes
      BasicBlock → AnyRef → Any

78. #### def touched: Boolean

    Has this basic block been modified since the last call to 'successors'?

79. #### def touched_=(b: Boolean): Unit

80. #### val varsInScope: Set[ICodes.Local]

    Local variables that are in scope at entry of this basic block.

    Local variables that are in scope at entry of this basic block. Used for debugging information.

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

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

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

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

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

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

84. #### def →[B](y: B): (ICodes.BasicBlock, B)

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

### Inherited from ProgramPoint[ICodes.BasicBlock]

### Inherited from AnyRef

### Inherited from Any

### Inherited by implicit conversion any2stringadd from ICodes.BasicBlock to any2stringadd[ICodes.BasicBlock]

### Inherited by implicit conversion StringFormat from ICodes.BasicBlock to StringFormat[ICodes.BasicBlock]

### Inherited by implicit conversion Ensuring from ICodes.BasicBlock to Ensuring[ICodes.BasicBlock]

### Inherited by implicit conversion ArrowAssoc from ICodes.BasicBlock to ArrowAssoc[ICodes.BasicBlock]

### Ungrouped