com.ibm.wala.cast.ir.ssa

Class AbstractSSAConversion

java.lang.Object

com.ibm.wala.cast.ir.ssa.AbstractSSAConversion

Direct Known Subclasses:

SSAConversion

public abstract class AbstractSSAConversion
extends java.lang.Object

Abstract core of traditional SSA conversion (Cytron et al.).

This implementation is abstract in the sense that it is designed to work over the instructions and CFG of a Domo IR, but it is abstract with respect to several integral portions of the traditional algorithm:

• The notion of uses and defs of a given instruction.
• Assignments (<def> := <use>) that are be copy-propagated away
• Which values are constants---i.e. have no definition.
• Any value numbers to be skipped during SSA construction
• Special initialization and exit block processing.

Field Summary

Fields

Modifier and Type	Field and Description
protected int[]	C
protected com.ibm.wala.ssa.SSACFG	CFG
protected com.ibm.wala.ssa.SSAOptions.DefaultValues	defaultValues
protected com.ibm.wala.util.graph.dominators.DominanceFrontiers<com.ibm.wala.ssa.ISSABasicBlock>	DF
protected com.ibm.wala.ssa.SSAInstruction[]	instructions
protected int[]	phiCounts
protected com.ibm.wala.util.collections.IntStack[]	S
protected com.ibm.wala.ssa.SymbolTable	symbolTable
protected int[]	valueMap

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	AbstractSSAConversion(com.ibm.wala.ssa.IR ir, com.ibm.wala.ssa.SSAOptions options)

Method Summary

Modifier and Type	Method and Description
protected void	fail(int v)
protected abstract int	getDef(com.ibm.wala.ssa.SSAInstruction inst, int index)
protected int	getDefaultValue(int valueNumber)
protected com.ibm.wala.ssa.SSAInstruction[]	getInstructions(com.ibm.wala.ssa.IR ir)
protected abstract int	getMaxValueNumber()
protected abstract int	getNextNewValueNumber()
protected abstract int	getNumberOfDefs(com.ibm.wala.ssa.SSAInstruction inst)
protected abstract int	getNumberOfUses(com.ibm.wala.ssa.SSAInstruction inst)
protected abstract com.ibm.wala.ssa.SSAPhiInstruction	getPhi(com.ibm.wala.ssa.SSACFG.BasicBlock B, int index)
protected abstract int	getUse(com.ibm.wala.ssa.SSAInstruction inst, int index)
protected boolean	hasDefaultValue(int valueNumber)
protected void	init()
protected abstract void	initializeVariables()
protected abstract boolean	isAssignInstruction(com.ibm.wala.ssa.SSAInstruction inst)
protected abstract boolean	isConstant(int valueNumber)
protected abstract boolean	isLive(com.ibm.wala.ssa.SSACFG.BasicBlock Y, int V)
protected java.util.Iterator<com.ibm.wala.ssa.SSAInstruction>	iterateInstructions(com.ibm.wala.ssa.IR ir)
protected void	perform()
protected abstract void	placeNewPhiAt(int value, com.ibm.wala.ssa.SSACFG.BasicBlock Y)
protected void	placePhiNodes()
protected abstract void	popAssignment(com.ibm.wala.ssa.SSAInstruction inst, int index)
protected abstract void	pushAssignment(com.ibm.wala.ssa.SSAInstruction inst, int index, int newRhs)
protected abstract void	repairExit()
protected abstract void	repairInstructionDefs(com.ibm.wala.ssa.SSAInstruction inst, int index, int[] newDefs, int[] newUses)
protected abstract void	repairInstructionUses(com.ibm.wala.ssa.SSAInstruction inst, int index, int[] newUses)
protected abstract com.ibm.wala.ssa.SSAPhiInstruction	repairPhiDefs(com.ibm.wala.ssa.SSAPhiInstruction phi, int[] newDefs)
protected abstract void	repairPhiUse(com.ibm.wala.ssa.SSACFG.BasicBlock BB, int phiIndex, int rvalIndex, int newRval)
protected abstract void	setPhi(com.ibm.wala.ssa.SSACFG.BasicBlock B, int index, com.ibm.wala.ssa.SSAPhiInstruction inst)
protected abstract boolean	skip(int vn)
protected boolean	skipRepair(com.ibm.wala.ssa.SSAInstruction inst, int index)
protected int	top(int v)

Methods inherited from class java.lang.Object

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

Field Detail

CFG

protected final com.ibm.wala.ssa.SSACFG CFG

DF

protected final com.ibm.wala.util.graph.dominators.DominanceFrontiers<com.ibm.wala.ssa.ISSABasicBlock> DF

phiCounts

protected final int[] phiCounts

instructions

protected final com.ibm.wala.ssa.SSAInstruction[] instructions

symbolTable

protected final com.ibm.wala.ssa.SymbolTable symbolTable

defaultValues

protected final com.ibm.wala.ssa.SSAOptions.DefaultValues defaultValues

S

protected com.ibm.wala.util.collections.IntStack[] S

C

protected int[] C

valueMap

protected int[] valueMap

Constructor Detail

AbstractSSAConversion

protected AbstractSSAConversion(com.ibm.wala.ssa.IR ir,
                                com.ibm.wala.ssa.SSAOptions options)

Method Detail

getNumberOfDefs

protected abstract int getNumberOfDefs(com.ibm.wala.ssa.SSAInstruction inst)

getDef

protected abstract int getDef(com.ibm.wala.ssa.SSAInstruction inst,
                              int index)

getNumberOfUses

protected abstract int getNumberOfUses(com.ibm.wala.ssa.SSAInstruction inst)

getUse

protected abstract int getUse(com.ibm.wala.ssa.SSAInstruction inst,
                              int index)

isAssignInstruction

protected abstract boolean isAssignInstruction(com.ibm.wala.ssa.SSAInstruction inst)

getMaxValueNumber

protected abstract int getMaxValueNumber()

isLive

protected abstract boolean isLive(com.ibm.wala.ssa.SSACFG.BasicBlock Y,
                                  int V)

skip

protected abstract boolean skip(int vn)

isConstant

protected abstract boolean isConstant(int valueNumber)

getNextNewValueNumber

protected abstract int getNextNewValueNumber()

initializeVariables

protected abstract void initializeVariables()

repairExit

protected abstract void repairExit()

placeNewPhiAt

protected abstract void placeNewPhiAt(int value,
                                      com.ibm.wala.ssa.SSACFG.BasicBlock Y)

getPhi

protected abstract com.ibm.wala.ssa.SSAPhiInstruction getPhi(com.ibm.wala.ssa.SSACFG.BasicBlock B,
                                                             int index)

setPhi

protected abstract void setPhi(com.ibm.wala.ssa.SSACFG.BasicBlock B,
                               int index,
                               com.ibm.wala.ssa.SSAPhiInstruction inst)

repairPhiDefs

protected abstract com.ibm.wala.ssa.SSAPhiInstruction repairPhiDefs(com.ibm.wala.ssa.SSAPhiInstruction phi,
                                                                    int[] newDefs)

repairPhiUse

protected abstract void repairPhiUse(com.ibm.wala.ssa.SSACFG.BasicBlock BB,
                                     int phiIndex,
                                     int rvalIndex,
                                     int newRval)

repairInstructionUses

protected abstract void repairInstructionUses(com.ibm.wala.ssa.SSAInstruction inst,
                                              int index,
                                              int[] newUses)

repairInstructionDefs

protected abstract void repairInstructionDefs(com.ibm.wala.ssa.SSAInstruction inst,
                                              int index,
                                              int[] newDefs,
                                              int[] newUses)

pushAssignment

protected abstract void pushAssignment(com.ibm.wala.ssa.SSAInstruction inst,
                                       int index,
                                       int newRhs)

popAssignment

protected abstract void popAssignment(com.ibm.wala.ssa.SSAInstruction inst,
                                      int index)

perform

protected void perform()

getInstructions

protected com.ibm.wala.ssa.SSAInstruction[] getInstructions(com.ibm.wala.ssa.IR ir)

iterateInstructions

protected final java.util.Iterator<com.ibm.wala.ssa.SSAInstruction> iterateInstructions(com.ibm.wala.ssa.IR ir)

init

protected void init()

placePhiNodes

protected void placePhiNodes()

skipRepair

protected boolean skipRepair(com.ibm.wala.ssa.SSAInstruction inst,
                             int index)

fail

protected void fail(int v)

hasDefaultValue

protected boolean hasDefaultValue(int valueNumber)

getDefaultValue

protected int getDefaultValue(int valueNumber)

top

protected int top(int v)