Package edu.umd.cs.findbugs.ba.vna

Class ValueNumberCache

java.lang.Object

edu.umd.cs.findbugs.ba.vna.ValueNumberCache

public class ValueNumberCache
extends Object

A cache mapping instructions and input values to the output values they produce. We must always produce the same output given identical input, or else value number analysis will not terminate.

Author:

David Hovemeyer

See Also:

• ValueNumberAnalysis

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	ValueNumberCache.Entry	An entry in the cache.

Constructor Summary

Constructors

Constructor	Description
ValueNumberCache()

Method Summary

Modifier and Type	Method	Description
void	addOutputValues(ValueNumberCache.Entry entry, ValueNumber[] outputValueList)	Add output values for given entry.
ValueNumber[]	lookupOutputValues(ValueNumberCache.Entry entry)	Look up cached output values for given entry.

Methods inherited from class java.lang.Object

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

Constructor Details

ValueNumberCache

public ValueNumberCache()

Method Details

lookupOutputValues

public ValueNumber[] lookupOutputValues(ValueNumberCache.Entry entry)

Look up cached output values for given entry.

Parameters:

entry - the entry

Returns:

the list of output values, or null if there is no matching entry in the cache

addOutputValues

public void addOutputValues(ValueNumberCache.Entry entry,
 ValueNumber[] outputValueList)

Add output values for given entry. Assumes that lookupOutputValues() has determined that the entry is not in the cache.

Parameters:

entry - the entry

outputValueList - the list of output values produced by the entry's instruction and input values