2 * Copyright (C) 2014, United States Government, as represented by the
3 * Administrator of the National Aeronautics and Space Administration.
6 * The Java Pathfinder core (jpf-core) platform is licensed under the
7 * Apache License, Version 2.0 (the "License"); you may not use this file except
8 * in compliance with the License. You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0.
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
19 package gov.nasa.jpf.perturb;
21 import gov.nasa.jpf.Config;
22 import gov.nasa.jpf.vm.ChoiceGenerator;
23 import gov.nasa.jpf.vm.IntChoiceGenerator;
24 import gov.nasa.jpf.vm.StackFrame;
25 import gov.nasa.jpf.vm.choice.IntChoiceFromSet;
28 * simple +/- delta perturbation of integer operand values
30 public class IntOverUnder implements OperandPerturbator {
35 public IntOverUnder (Config conf, String keyPrefix) {
36 delta = conf.getInt(keyPrefix + ".delta", 0);
40 public IntOverUnder (int delta){
46 public ChoiceGenerator<?> createChoiceGenerator (String id, StackFrame frame, Object refObject){
47 int val = frame.peek(offset);
49 int[] values = new int[3];
51 values[0] = val + delta;
53 values[2] = val - delta;
55 // set offset from refObject
56 offset = (Integer)refObject;
58 return new IntChoiceFromSet(id, values);
62 public boolean perturb(ChoiceGenerator<?>cg, StackFrame frame) {
63 assert cg instanceof IntChoiceGenerator : "wrong choice generator type for IntOverUnder: " + cg.getClass().getName();
65 int val = ((IntChoiceGenerator)cg).getNextChoice();
66 frame.setOperand(offset, val, false);
67 return cg.hasMoreChoices();
71 public Class<? extends ChoiceGenerator<?>> getChoiceGeneratorType(){
72 return IntChoiceFromSet.class;