/* Soot - a J*va Optimization Framework
* Copyright (C) 2003 Ondrej Lhotak
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
package soot.util;
import soot.*;
public final class SharedBitSetCache {
public SharedBitSetCache( Singletons.Global g ) {}
public static SharedBitSetCache v() { return G.v().soot_util_SharedBitSetCache(); }
public static final int size = 32749; // a nice prime about 32k
public BitVector[] cache = new BitVector[size];
public BitVector[] orAndAndNotCache = new BitVector[size];
public BitVector canonicalize( BitVector set ) {
int hash = set.hashCode();
if( hash < 0 ) hash = -hash;
hash %= size;
if( cache[hash] == null || !cache[hash].equals(set) ) {
return cache[hash] = set;
}
return cache[hash];
}
}