at.dms.kjc.flatgraph
Class GraphFlattener

java.lang.Object
  at.dms.util.Utils
      at.dms.kjc.flatgraph.GraphFlattener

All Implemented Interfaces:

DeepCloneable, Serializable

public class GraphFlattener
extends Utils

This class will create a graph of FlatNode that represents the underlying SIR graph of the application. It is basically the SIR graph without containers.

The constructed graph of FlatNodes, the Flat graph, will have one node for each SIROperator in the SIR graph (except when --sync is enabled), but there will exist no containers, FlatNodes directly connect to/from their downstream/upstream nodes.

Each SIROperator will be converted to a FlatNode: SIRFilter into a FlatNode with at most one input/one output, SIRSplitter into a multiple output/one input, SIRJoiner into multiple input/one output.

If --sync is enabled, it will attempt to coalesce multiple splitters or joiners into a single FlatNode.

Author:

mgordon

See Also:

Serialized Form

Field Summary

static LinkedList<FlatNode>	needsToBeSched Used by --sync (synch removal) to reschedule the flat graph
FlatNode	top the toplevel, entry, FlatNode of the constructed Flat graph

Fields inherited from class at.dms.util.Utils

EMPTY_LIST, getForLoopCallers

Constructor Summary

GraphFlattener(SIROperator toplevel)
Create a graph of FlatNodes that represents the SIR graph of the application rooted at toplevel.

Method Summary

static boolean	countMe(SIRFilter filter) Return true if this filter should be mapped to a tile, meaning it is not a predefined filter.
FlatNode	getFlatNode(SIROperator key) Given an SIROperator, key, return the FlatNode that was created to represent key, or null if one was not created.
static CType	getJoinerType(FlatNode joiner) Return the data type of items that flow through joiner.
static int	getMult(FlatNode node, boolean init, HashMap<FlatNode,Integer> initExecutionCounts, HashMap<FlatNode,Integer> steadyExecutionCounts) Return the multiplicity of node in the schedule determined by init.
int	getNumTiles() Returns the number of tiles that would be needed to execute this graph.
static CType	getOutputType(FlatNode node) Return the output type of the FlatNode node.

Methods inherited from class at.dms.util.Utils

asPercent, cellMathEquivalent, cMathEquivalent, cppMathEquivalent, deepClone, deepCloneInto, equalArrays, fail, getEnvironmentVariable, getExpression, hasPeeks, initArray, initArray, initLiteralArray, intArrayToList, isMathMethod, isUniform, kopi_assert, kopi_assert, makeCountdownForLoop, makeDotFileName, makeForLoop, makeForLoop, makeForLoop, makeForLoopFieldIndex, makeForLoopLocalIndex, nextPow2, passThruParens, peelMarkers, popBeforePeek, readFile, removeUnusedPops, replaceAll, setupDotFileName, simplifyMathMethod, splitQualifiedName, splitQualifiedName, toArray, toIntArray, toVector, voidToInt, writeFile

Methods inherited from class java.lang.Object

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

Field Detail

top

public FlatNode top

the toplevel, entry, FlatNode of the constructed Flat graph

needsToBeSched

public static LinkedList<FlatNode> needsToBeSched

Used by --sync (synch removal) to reschedule the flat graph

Constructor Detail

GraphFlattener

public GraphFlattener(SIROperator toplevel)

Create a graph of FlatNodes that represents the SIR graph of the application rooted at toplevel. If --sync is enabled, then try to coalesce multiple splitters or joiners into a single FlatNode.

Parameters:

toplevel - The toplevel SIR container of the application.

Method Detail

getNumTiles

public int getNumTiles()

Returns the number of tiles that would be needed to execute this graph. That is, just counts the filters, plus any joiners whose output is not connected to another joiner. This is used only for the SpaceDynamic and the original at.dms.kjc.raw backends.

Returns:

The number of tiles needed to map this graph to raw.

getFlatNode

public FlatNode getFlatNode(SIROperator key)

Given an SIROperator, key, return the FlatNode that was created to represent key, or null if one was not created.

Parameters:

key -

Returns:

the FlatNode that was created to represent key, or null if one was not created.

getOutputType

public static CType getOutputType(FlatNode node)

Return the output type of the FlatNode node.

Parameters:

node - The FlatNode in question.

Returns:

node's output type.

countMe

public static boolean countMe(SIRFilter filter)

Return true if this filter should be mapped to a tile, meaning it is not a predefined filter.

Parameters:

filter - The SIRFilter is question.

Returns:

true if this filter should be mapped to a tile, meaning it is not a predefined filter.

getJoinerType

public static CType getJoinerType(FlatNode joiner)

Return the data type of items that flow through joiner.

Parameters:

joiner - The joiner

Returns:

The CType of items that flow through joiner.

getMult

public static int getMult(FlatNode node,
                          boolean init,
                          HashMap<FlatNode,Integer> initExecutionCounts,
                          HashMap<FlatNode,Integer> steadyExecutionCounts)

Return the multiplicity of node in the schedule determined by init. If node does not appear in the schedule, return 0;

Parameters:

node -

init - If true use initExecutionCounts, else use steadyExecutionCounts

initExecutionCounts - HashMap of FlatNode->Integer for init multiplicities

steadyExecutionCounts - HashMap of FlatNode->Integer for steadyx multiplicities

Returns:

The multiplicity of node in init if init == true or steady of init == false, or -1 if the corresponding HashMap is null, or 0 if the node does not appear in the schedule for the stage.