Package org.jruby.ir.dataflow.analyses

Class LiveVariableNode

java.lang.Object

org.jruby.ir.dataflow.FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

org.jruby.ir.dataflow.analyses.LiveVariableNode

public class LiveVariableNode
extends FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

Field Summary

Fields

Modifier and Type	Field	Description
private BitSet	in
private BitSet	living
private BitSet	out
private int	setSize

Fields inherited from class org.jruby.ir.dataflow.FlowGraphNode

basicBlock, problem

Constructor Summary

Constructors

Constructor	Description
LiveVariableNode(LiveVariablesProblem prob, BasicBlock n)

Method Summary

Modifier and Type	Method	Description
private void	addDFVar(Variable v)
void	applyPreMeetHandler()	Initialize this data flow node to compute the new solution This is done before iteratively calling the MEET operator.
void	applyTransferFunction(Instr i)	Apply transfer function to the instruction
void	buildDataFlowVars(Instr i)	Builds the data-flow variables (or facts) for a particular instruction.
void	compute_MEET(org.jruby.dirgra.Edge e, LiveVariableNode pred)	"MEET" current solution of "IN/OUT" with "OUT/IN(pred)", where "pred" is a predecessor of the current node! The choice of "IN/OUT" is determined by the direction of data flow.
void	finalizeSolution()	Any required cleanup of state after applying transfer function
(package private) BitSet	getLiveInBitSet()
(package private) BitSet	getLiveOutBitSet()
void	init()	Initialize this data flow node for solving the current problem This is done after building dataflow variables for the problem.
void	initSolution()	Any setting up of state/initialization before applying transfer function
private void	makeOutExceptionVariablesLiving()	Collect variables live out of the exception target node.
private void	markAllVariablesLive(LiveVariablesProblem lvp, Collection<? extends Variable> variableList)
(package private) void	markDeadInstructions()
private void	markVariableLive(LiveVariablesProblem lvp, Variable x)
boolean	solutionChanged()	Did dataflow solution for this node change from last time?
String	toString()

Methods inherited from class org.jruby.ir.dataflow.FlowGraphNode

buildDataFlowVars, computeDataFlowInfo, computeDataFlowInfoBackward, computeDataFlowInfoForward, getBB, getCFG, getExceptionTargetNode, hasExceptionsRescued

Methods inherited from class java.lang.Object

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

Field Details

in

private BitSet in

out

private BitSet out

living

private BitSet living

setSize

private int setSize

Constructor Details

LiveVariableNode

public LiveVariableNode(LiveVariablesProblem prob,
 BasicBlock n)

Method Details

init

public void init()

Description copied from class: FlowGraphNode

Initialize this data flow node for solving the current problem This is done after building dataflow variables for the problem.

Overrides:

init in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

addDFVar

private void addDFVar(Variable v)

buildDataFlowVars

public void buildDataFlowVars(Instr i)

Description copied from class: FlowGraphNode

Builds the data-flow variables (or facts) for a particular instruction.

Specified by:

buildDataFlowVars in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

applyPreMeetHandler

public void applyPreMeetHandler()

Description copied from class: FlowGraphNode

Initialize this data flow node to compute the new solution This is done before iteratively calling the MEET operator.

Specified by:

applyPreMeetHandler in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

compute_MEET

public void compute_MEET(org.jruby.dirgra.Edge e,
 LiveVariableNode pred)

Description copied from class: FlowGraphNode

"MEET" current solution of "IN/OUT" with "OUT/IN(pred)", where "pred" is a predecessor of the current node! The choice of "IN/OUT" is determined by the direction of data flow.

Specified by:

compute_MEET in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

markAllVariablesLive

private void markAllVariablesLive(LiveVariablesProblem lvp,
 Collection<? extends Variable> variableList)

markVariableLive

private void markVariableLive(LiveVariablesProblem lvp,
 Variable x)

initSolution

public void initSolution()

Description copied from class: FlowGraphNode

Any setting up of state/initialization before applying transfer function

Overrides:

initSolution in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

applyTransferFunction

public void applyTransferFunction(Instr i)

Description copied from class: FlowGraphNode

Apply transfer function to the instruction

Specified by:

applyTransferFunction in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

solutionChanged

public boolean solutionChanged()

Description copied from class: FlowGraphNode

Did dataflow solution for this node change from last time?

Specified by:

solutionChanged in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

finalizeSolution

public void finalizeSolution()

Description copied from class: FlowGraphNode

Any required cleanup of state after applying transfer function

Overrides:

finalizeSolution in class FlowGraphNode<LiveVariablesProblem,LiveVariableNode>

makeOutExceptionVariablesLiving

private void makeOutExceptionVariablesLiving()

Collect variables live out of the exception target node. Since this instr. can directly jump to the rescue block (or scope exit) without executing the rest of the instructions in this bb, we have a control-flow edge from this instr. to that block. Since we dont want to add a control-flow edge from pretty much every instr. to the rescuer/exit BB, we are handling it implicitly here.

toString

public String toString()

Overrides:

toString in class Object

markDeadInstructions

void markDeadInstructions()

getLiveInBitSet

BitSet getLiveInBitSet()

getLiveOutBitSet

BitSet getLiveOutBitSet()