coins.ssa
Class SsaGraph

java.lang.Object
  coins.ssa.SsaGraph

All Implemented Interfaces:

LocalTransformer, Transformer

class SsaGraph

extends java.lang.Object

implements LocalTransformer

SSA graph

This class defined the object of the SSA graph. Ths SSA graph has nodes which have the value or operator and labeled by the variable that defined by the value or operation. The edge of the node of the SSA graph is from the node that value is used to the node that value is defined.

Reference:
Bowen Alpern and Mark N. Wegman and F. Kenneth Zadeck, "Detecting Equality of Variables in Programs," Proceedings of the Fifteenth Annual ACM Symposium on Principles of Programming Language, pp. 1-11, January, 1988.

Field Summary

java.lang.String	optName The name of the optimizer which uses SSA graph
static java.lang.String	symName The prefix of the new symbol
static int	THR The threshold of the debug print

Constructor Summary

SsaGraph(SsaEnvironment e, SsaSymTab symtab, java.lang.String opt)
Constructor

Method Summary

(package private) SsaGraphNode	appendNode(LirNode node, BasicBlk blk, int numOfParents) Append a new node to the SSA graph.
boolean	doIt(Data data, ImList args) Transform the DATA component.
boolean	doIt(Function function, ImList args) Make the SSA graph and optimize with the graph.
java.lang.String	name() Return the name of the transforming engine.
(package private) BiList	nodeList() Return the list of the node of the SSA graph.
(package private) void	printGraph(java.lang.String filename) Print the node as graphviz format.
(package private) void	setSymbol(Symbol s, SsaGraphNode node) Register again the symbol `s' as a value of the node and put it to the map.
java.lang.String	subject() Return brief description of the tranformation.

Methods inherited from class java.lang.Object

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

Field Detail

symName

public static final java.lang.String symName

The prefix of the new symbol

See Also:

Constant Field Values

optName

public final java.lang.String optName

The name of the optimizer which uses SSA graph

THR

public static final int THR

The threshold of the debug print

See Also:

Constant Field Values

Constructor Detail

SsaGraph

public SsaGraph(SsaEnvironment e,
                SsaSymTab symtab,
                java.lang.String opt)

Constructor

Parameters:

e - The environment of the SSA module

symtab - The current symbol table of the SSA module

opt - The name of the optimizer which uses the SSA graph

Method Detail

doIt

public boolean doIt(Data data,
                    ImList args)

Description copied from interface: LocalTransformer

Transform the DATA component.

Specified by:

doIt in interface LocalTransformer

Parameters:

data - DATA to be transformed.

args - list of optional arguments.

Returns:

true if transformation suceeded.

name

public java.lang.String name()

Description copied from interface: Transformer

Return the name of the transforming engine. Used for trace tag name.

Specified by:

name in interface Transformer

Returns:

the name of the transforming engine.

subject

public java.lang.String subject()

Description copied from interface: Transformer

Return brief description of the tranformation.

Specified by:

subject in interface Transformer

Returns:

brief description of the tranformation.

doIt

public boolean doIt(Function function,
                    ImList args)

Make the SSA graph and optimize with the graph.

Specified by:

doIt in interface LocalTransformer

Parameters:

function - the current function

args - The list of options

Returns:

true if transformation suceeded.

appendNode

SsaGraphNode appendNode(LirNode node,
                        BasicBlk blk,
                        int numOfParents)

Append a new node to the SSA graph.

Parameters:

node - The LIR node which append into the graph

blk - The basic block which the LIR node belongs to

numOfParents - The number of references of the node

Returns:

A new node of the SSA graph

nodeList

BiList nodeList()

Return the list of the node of the SSA graph.

Returns:

The list of the node of the SSA graph

setSymbol

void setSymbol(Symbol s,
               SsaGraphNode node)

Register again the symbol `s' as a value of the node and put it to the map. If the map already has `s', then remove the old one and register again.

Parameters:

s - The symbol to register

node - The node of the SSA graph which has `s'

printGraph

void printGraph(java.lang.String filename)

Print the node as graphviz format.

Parameters:

filename - The file name for output