harpoon.Analysis.DataFlow
Class LiveVars.BBVisitor

java.lang.Object
  harpoon.Analysis.BasicBlockInterfVisitor
      harpoon.Analysis.DataFlow.DataFlowBasicBlockVisitor
          harpoon.Analysis.DataFlow.BackwardDataFlowBasicBlockVisitor
              harpoon.Analysis.DataFlow.LiveVars.BBVisitor

Direct Known Subclasses:

LiveTemps

Enclosing class:

LiveVars

public abstract static class LiveVars.BBVisitor
extends BackwardDataFlowBasicBlockVisitor

Nested Class Summary

protected static class

LiveVars.BBVisitor.LiveVarInfo

Field Summary

protected BasicBlock.Factory

bbFact

Constructor Summary

	LiveVars.BBVisitor(BasicBlock.Factory bbFact) Constructs a new LiveVars for basicblocks.
protected	LiveVars.BBVisitor(BasicBlock.Factory bbFact, boolean ignore) Special ctor for use by subclasses so that the system won't break when calling abstract methods that require data that subclasses haven't initialized yet.
	LiveVars.BBVisitor(BasicBlock.Factory bbFact, SetFactory tempSetFact) Constructor for LiveVars that allows the user to pass in their own SetFactory for constructing sets of whatever variable types that are used in the analysis.

Method Summary

String	dump()
String	dump(boolean dumpInstrs)
protected abstract Set	findUniverse(Set blockSet) Constructs a Set of all of the referenced variables in blocks.
Set	getLiveOnEntry(BasicBlock b) Returns the Set of variables that are live on entry to b.
Set	getLiveOnExit(BasicBlock b) Returns the Set of variables that are live on exit from b.
protected void	initializeBBtoLVI(Set blockSet, SetFactory setFact)
protected abstract LiveVars.BBVisitor.LiveVarInfo	makeUseDef(BasicBlock bb, SetFactory sf) Initializes the USE/DEF information for bb and stores it in the returned LiveVarInfo.
boolean	merge(BasicBlockInterf child, BasicBlockInterf parent) Merge (Confluence) operator.
void	visit(BasicBlock b) Visit (Transfer) function.

Methods inherited from class harpoon.Analysis.DataFlow.BackwardDataFlowBasicBlockVisitor

addSuccessors

Methods inherited from class harpoon.Analysis.DataFlow.DataFlowBasicBlockVisitor

db, visit

Methods inherited from class harpoon.Analysis.BasicBlockInterfVisitor

visit

Methods inherited from class java.lang.Object

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

Field Detail

bbFact

protected BasicBlock.Factory bbFact

Constructor Detail

LiveVars.BBVisitor

protected LiveVars.BBVisitor(BasicBlock.Factory bbFact,
                             boolean ignore)

Special ctor for use by subclasses so that the system won't break when calling abstract methods that require data that subclasses haven't initialized yet.

LiveVars.BBVisitor

public LiveVars.BBVisitor(BasicBlock.Factory bbFact)

Constructs a new LiveVars for basicblocks.
requires: All of the statements in bbFact implement UseDefable
effects: constructs a new BasicBlockVisitor and initializes its internal datasets for analysis of the BasicBlocks in bbFact.

Parameters:

bbFact - BasicBlock.Factory containing BasicBlocks to be analyzed.

LiveVars.BBVisitor

public LiveVars.BBVisitor(BasicBlock.Factory bbFact,
                          SetFactory tempSetFact)

Constructor for LiveVars that allows the user to pass in their own SetFactory for constructing sets of whatever variable types that are used in the analysis.
requires:

1. All Temps in bbFact are members of the universe for tempSetFact.
2. All of the statements in bbFact implement UseDefable

effects: constructs a new BasicBlockVisitor and initializes its internal datasets for analysis of the BasicBlocks in bbFact.

Method Detail

initializeBBtoLVI

protected void initializeBBtoLVI(Set blockSet,
                                 SetFactory setFact)

findUniverse

protected abstract Set findUniverse(Set blockSet)

Constructs a Set of all of the referenced variables in blocks. For example, in some analyses this universe will be made up of all of the Temps referenced in blocks. However, for flexibility I have allowed users to define their own universe of values (such as Webs).

merge

public boolean merge(BasicBlockInterf child,
                     BasicBlockInterf parent)

Merge (Confluence) operator.
LVout(bb) = Union over (j elem Succ(bb)) of ( LVin(j) )
parent corresponds to 'bb' above, while child corresponds to a member of Succ('bb'). It is the responsibility of the DataFlow Equation Solver to run merge on all of the Succ('bb')
This method isn't meant to be called by application code; instead, look at one of the DataFlow Equation Solvers in the harpoon.Analysis.DataFlow package.
requires: child and parent are contained in this
effects: Updates the internal information associated with to to include information associated with from

Specified by:

merge in class DataFlowBasicBlockVisitor

See Also:

InstrSolver

visit

public void visit(BasicBlock b)

Visit (Transfer) function.
LVin(bb) = ( LVout(bb) - DEF(bb) ) union USE(bb)

Specified by:

visit in class DataFlowBasicBlockVisitor

makeUseDef

protected abstract LiveVars.BBVisitor.LiveVarInfo makeUseDef(BasicBlock bb,
                                                             SetFactory sf)

Initializes the USE/DEF information for bb and stores it in the returned LiveVarInfo. An example implementation would use Temps to make up their LiveVarInfos.

getLiveOnEntry

public Set getLiveOnEntry(BasicBlock b)

Returns the Set of variables that are live on entry to b.
requires: A DataFlow Solver has been run to completion on the graph of BasicBlocks containing b with this as the DataFlowBasicBlockVisitor.

getLiveOnExit

public Set getLiveOnExit(BasicBlock b)

Returns the Set of variables that are live on exit from b.
requires: A DataFlow Equation Solver has been run to completion on the graph of BasicBlocks containing b with this as the DataFlowBasicBlockVisitor.

dump

public String dump()

dump

public String dump(boolean dumpInstrs)