Package org.apache.sysds.hops.rewrite

Class RewriteRemoveDanglingParentReferences

java.lang.Object

org.apache.sysds.hops.rewrite.HopRewriteRule

org.apache.sysds.hops.rewrite.RewriteRemoveDanglingParentReferences

public class RewriteRemoveDanglingParentReferences
extends HopRewriteRule

This rewrite is a general-purpose cleanup pass that removes any dangling parent references in one pass through the hop DAG. These dangling references could have been introduced by rewrites that remove operators but miss a proper cleanup.

Constructor Summary

Constructors

Constructor	Description
RewriteRemoveDanglingParentReferences()

Method Summary

Modifier and Type	Method	Description
Hop	rewriteHopDAG(Hop root, ProgramRewriteStatus state)	Handle a predicate hop DAG with exactly one root.
ArrayList<Hop>	rewriteHopDAGs(ArrayList<Hop> roots, ProgramRewriteStatus state)	Handle a generic (last-level) hop DAG with multiple roots.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

RewriteRemoveDanglingParentReferences

public RewriteRemoveDanglingParentReferences()

Method Detail

rewriteHopDAGs

public ArrayList<Hop> rewriteHopDAGs(ArrayList<Hop> roots,
                                     ProgramRewriteStatus state)

Description copied from class: HopRewriteRule

Handle a generic (last-level) hop DAG with multiple roots.

Specified by:

rewriteHopDAGs in class HopRewriteRule

Parameters:

roots - high-level operator roots

state - program rewrite status

Returns:

list of high-level operators

rewriteHopDAG

public Hop rewriteHopDAG(Hop root,
                         ProgramRewriteStatus state)

Description copied from class: HopRewriteRule

Handle a predicate hop DAG with exactly one root.

Specified by:

rewriteHopDAG in class HopRewriteRule

Parameters:

root - high-level operator root

state - program rewrite status

Returns:

high-level operator