org.apache.tuweni.progpow.KISS99Random Maven / Gradle / Ivy
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* Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE
* file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file
* to You under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the
* License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
* an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
* specific language governing permissions and limitations under the License.
*/
package org.apache.tuweni.progpow;
import org.apache.tuweni.units.bigints.UInt32;
final class KISS99Random {
private static final UInt32 FILTER = UInt32.valueOf(65535);
UInt32 z;
UInt32 w;
UInt32 jsr;
UInt32 jcong;
KISS99Random(UInt32 z, UInt32 w, UInt32 jsr, UInt32 jcong) {
this.z = z;
this.w = w;
this.jsr = jsr;
this.jcong = jcong;
}
UInt32 generate() {
z = (z.and(FILTER).multiply(UInt32.valueOf(36969))).add(z.shiftRight(16));
w = (w.and(FILTER).multiply(UInt32.valueOf(18000))).add(w.shiftRight(16));
UInt32 mwc = z.shiftLeft(16).add(w);
jsr = jsr.xor(jsr.shiftLeft(17));
jsr = jsr.xor(jsr.shiftRight(13));
jsr = jsr.xor(jsr.shiftLeft(5));
jcong = (jcong.multiply(UInt32.valueOf(69069))).add(UInt32.valueOf(1234567));
return mwc.xor(jcong).add(jsr);
}
}