EDU.purdue.cs.bloat.trans

Class SSAPRE

java.lang.Object

EDU.purdue.cs.bloat.trans.SSAPRE

public class SSAPRE
extends java.lang.Object

Perform partial redundancy elimination of a CFG in SSA form using the SSA-based algorithm described in:

     Fred Chow, Sun Chan, Robert Kennedy, Shin-Ming Liu, Raymond Lo,
     and Peng Tu, "A New Algorithm for Partial Redundancy Elimination
     based on SSA Form", Proc. PLDI '97: 273-286, 1997.
 

NOTE: The type for all occurrences of an inserted variable is the same as the type of the first occurrence of the expression the variable replaces. This type is guaranteed since we only group expression with equal types.

Field Summary

Fields

Modifier and Type	Field and Description
protected FlowGraph	cfg
protected EditorContext	context
static boolean	DEBUG
protected ResizeableArrayList[]	kills
protected boolean[]	killsSorted
protected int	nextValueNumber
static boolean	NO_ACCESS_PATHS
static boolean	NO_PRECISE
static boolean	NO_THREAD
protected java.util.HashMap	phiRelated
protected SideEffectChecker	sideEffects
protected EDU.purdue.cs.bloat.trans.SSAPRE.ExprWorklist	worklist

Constructor Summary

Constructors

Constructor and Description
SSAPRE(FlowGraph cfg, EditorContext context) Constructor.

Method Summary

Methods

Modifier and Type	Method and Description
void	transform() Performs SSA-based partial redundency elimination (PRE) on a control flow graph.

Methods inherited from class java.lang.Object

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

Field Detail

DEBUG

public static boolean DEBUG

NO_THREAD

public static boolean NO_THREAD

NO_PRECISE

public static boolean NO_PRECISE

NO_ACCESS_PATHS

public static boolean NO_ACCESS_PATHS

cfg

protected FlowGraph cfg

nextValueNumber

protected int nextValueNumber

context

protected EditorContext context

kills

protected ResizeableArrayList[] kills

killsSorted

protected boolean[] killsSorted

sideEffects

protected SideEffectChecker sideEffects

worklist

protected EDU.purdue.cs.bloat.trans.SSAPRE.ExprWorklist worklist

phiRelated

protected java.util.HashMap phiRelated

Constructor Detail

SSAPRE

public SSAPRE(FlowGraph cfg,
      EditorContext context)

Constructor.

Parameters:

cfg - Control flow graph on which to perform SSA-based PRE.

context - The EditorContext containing all the classes that BLOAT knows about.

Method Detail

transform

public void transform()

Performs SSA-based partial redundency elimination (PRE) on a control flow graph.