harpoon.IR.Tree
Interface TreeDerivation

All Known Implementing Classes:

DerivationGenerator

public interface TreeDerivation

TreeDerivation provides a means to access type and derivation information for any Tree.Exp in a code representation.

Version:

$Id: TreeDerivation.java,v 1.2 2002/02/25 21:05:42 cananian Exp $

Author:

C. Scott Ananian <cananian@alumni.princeton.edu>

See Also:

Derivation, TypeMap

Method Summary

Derivation.DList	derivation(Exp exp) Returns the derivation of a given tree expression exp.
HClass	typeMap(Exp exp) Returns the type of a given tree expression exp.

Method Detail

typeMap

HClass typeMap(Exp exp)
               throws TypeMap.TypeNotKnownException

Returns the type of a given tree expression exp. If the type of the Tree.Exp is not known, throws TypeNotKnownException. If the Tree.Exp represents a derived pointer, null is returned, in which case the derivation() method must return a non-null value. HClass.Void is returned to indicate the type of a null pointer; as a special case, it is also returned to indicate the type of an opaque pointer value which does not correspond to a java object pointer or some derivation thereof and thus should not be traced during garbage collection.

Parameters:

exp - The tree expression to examine.

Returns:

the type of exp

Throws:

TypeMap.TypeNotKnownException - if the TreeDerivation does not have any information about exp.

See Also:

TypeMap

derivation

Derivation.DList derivation(Exp exp)
                            throws TypeMap.TypeNotKnownException

Returns the derivation of a given tree expression exp. If the derivation of the Tree.Exp is not known, throws TypeNotKnownException. If the Tree.Exp represents a non-derived base pointer, returns null, in which case the typeMap() method must return a non-null value.

Parameters:

exp - The tree expression to examine.

Returns:

the derivation of exp

Throws:

TypeMap.TypeNotKnownException - if the TreeDerivation does not have any information about exp.

See Also:

Derivation