Java tutorial
/** License information: * Component: checkedcoverage-core * Package: pku.sei.checkedcoverage.slicing * Class: Slicer * Filename: checkedcoverage-core/src/main/java/de/unisb/cs/st/checkedcoverage/slicing/Slicer.java * * This file is part of the checkedcoverage tool, developed by Clemens Hammacher at Saarland University. * See http://www.st.cs.uni-saarland.de/checkedcoverage/ for more information. * * This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License. * To view a copy of this license, visit http://creativecommons.org/licenses/by-sa/3.0/ or send a * letter to Creative Commons, 171 Second Street, Suite 300, San Francisco, California, 94105, USA. */ package pku.sei.checkedcoverage.slicing; import static org.objectweb.asm.Opcodes.INVOKESTATIC; import java.io.File; import java.io.IOException; import java.io.PrintStream; import java.io.PrintWriter; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.Iterator; import java.util.List; import java.util.Locale; import java.util.Set; import java.util.TreeMap; import java.util.TreeSet; import org.apache.commons.cli.CommandLine; import org.apache.commons.cli.CommandLineParser; import org.apache.commons.cli.GnuParser; import org.apache.commons.cli.HelpFormatter; import org.apache.commons.cli.OptionBuilder; import org.apache.commons.cli.Options; import org.apache.commons.cli.ParseException; import org.objectweb.asm.Opcodes; import de.hammacher.util.maps.IntegerMap; import pku.sei.checkedcoverage.common.classRepresentation.AbstractInstructionInstance; import pku.sei.checkedcoverage.common.classRepresentation.Instruction; import pku.sei.checkedcoverage.common.classRepresentation.InstructionInstanceFactory; import pku.sei.checkedcoverage.common.classRepresentation.InstructionInstanceInfo; import pku.sei.checkedcoverage.common.classRepresentation.InstructionType; import pku.sei.checkedcoverage.common.classRepresentation.LocalVariable; import pku.sei.checkedcoverage.common.classRepresentation.ReadMethod; import pku.sei.checkedcoverage.common.classRepresentation.instructions.AbstractInstruction; import pku.sei.checkedcoverage.common.classRepresentation.instructions.FieldInstruction; import pku.sei.checkedcoverage.common.classRepresentation.instructions.MethodInvocationInstruction; import pku.sei.checkedcoverage.common.classRepresentation.instructions.VarInstruction; import pku.sei.checkedcoverage.common.progress.ConsoleProgressMonitor; import pku.sei.checkedcoverage.common.progress.ProgressMonitor; import pku.sei.checkedcoverage.coverage.utils.Utils; import pku.sei.checkedcoverage.dependenceAnalysis.DataDependenceType; import pku.sei.checkedcoverage.dependenceAnalysis.DependencesExtractor; import pku.sei.checkedcoverage.dependenceAnalysis.DependencesVisitorAdapter; import pku.sei.checkedcoverage.dependenceAnalysis.VisitorCapability; import pku.sei.checkedcoverage.slicing.SlicingCriterion.SlicingCriterionInstance; import pku.sei.checkedcoverage.traceResult.PrintUniqueUntracedMethods; import pku.sei.checkedcoverage.traceResult.ThreadId; import pku.sei.checkedcoverage.traceResult.TraceResult; import pku.sei.checkedcoverage.traceResult.UntracedCallVisitor; import pku.sei.checkedcoverage.variables.Variable; /** * This is the new slicer implementation, built on top of the {@link DependencesExtractor}. * * There still exists another implementation {@link DirectSlicer} which is more performant and * should yield the same result. Nevertheless it is less maintained, so be alert. * * @author Clemens Hammacher */ public class Slicer { private static class SlicerInstance extends AbstractInstructionInstance { public boolean onDynamicSlice = false; // these variables are used to resolve which data dependences to follow: public boolean allDataInteresting = false; public boolean onlyIfAfterCriterion = false; public Variable interestingVariable = null; public Set<Variable> moreInterestingVariables = null; public Set<SlicerInstance> predecessors; // only set on labels and GOTOs public int criterionDistance; public SlicerInstance(AbstractInstruction instr, long occurenceNumber, int stackDepth, long instanceNr, InstructionInstanceInfo additionalInfo) { super(instr, occurenceNumber, stackDepth, instanceNr, additionalInfo); this.criterionDistance = Integer.MAX_VALUE; } } private static class SlicerInstanceFactory implements InstructionInstanceFactory<SlicerInstance> { public static final SlicerInstanceFactory instance = new SlicerInstanceFactory(); public SlicerInstance createInstructionInstance(AbstractInstruction instruction, long occurenceNumber, int stackDepth, long instanceNr, InstructionInstanceInfo additionalInfo) { return new SlicerInstance(instruction, occurenceNumber, stackDepth, instanceNr, additionalInfo); } } private final TraceResult trace; private final List<ProgressMonitor> progressMonitors = new ArrayList<ProgressMonitor>(1); private final List<SliceVisitor> sliceVisitors = new ArrayList<SliceVisitor>(1); private final List<UntracedCallVisitor> untracedCallVisitors = new ArrayList<UntracedCallVisitor>(1); private static HashMap<String, HashSet<Instruction>> checkedMap = new HashMap<String, HashSet<Instruction>>(); public Slicer(TraceResult trace) { this.trace = trace; } private static void clean() { checkedMap.clear(); } public static TreeSet<Integer> sliceUnchecked(String crit) { TreeSet<Integer> sliced = new TreeSet<Integer>(); File traceFile = new File(Utils.trace_file); String slicingCriterionString = crit; Long threadId = null; TraceResult trace = null; try { trace = TraceResult.readFrom(traceFile); } catch (IOException e) { System.err.format("Could not read the trace file \"%s\": %s%n", traceFile, e); System.exit(-1); } List<SlicingCriterion> sc = null; try { sc = SlicingCriterion.parseAll(slicingCriterionString, trace.getReadClasses()); } catch (IllegalArgumentException e) { System.err.println("Error parsing slicing criterion: " + e.getMessage()); System.exit(-1); } List<ThreadId> threads = trace.getThreads(); if (threads.size() == 0) { System.err.println("The trace file contains no tracing information."); System.exit(-1); } ThreadId tracing = null; for (ThreadId t : threads) { if (threadId == null) { if ("main".equals(t.getThreadName()) && (tracing == null || t.getJavaThreadId() < tracing.getJavaThreadId())) tracing = t; } else if (t.getJavaThreadId() == threadId.longValue()) { tracing = t; } } if (tracing == null) { System.err.println(threadId == null ? "Couldn't find the main thread." : "The thread you specified was not found."); System.exit(-1); } Slicer slicer = new Slicer(trace); boolean multithreaded = Runtime.getRuntime().availableProcessors() > 1; SliceInstructionsCollector collector = new SliceInstructionsCollector(); slicer.addSliceVisitor(collector); try { slicer.process(tracing, sc, multithreaded); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } Set<Instruction> slice = collector.getDynamicSlice(); Instruction[] sliceArray = slice.toArray(new Instruction[slice.size()]); Arrays.sort(sliceArray); for (Instruction insn : sliceArray) { String className = insn.getMethod().getReadClass().getName(); if (className.startsWith(Utils.focused_package)) { sliced.add(insn.getLineNumber()); // System.out.println(insn.getLineNumber()); } } return sliced; } public static void slice(String crit) { File traceFile = new File(Utils.trace_file); String slicingCriterionString = crit; Long threadId = null; TraceResult trace = null; System.out.println("\n\nSlice computation phase:"); System.out.println("Starting calculating the slice for trace file:" + Utils.trace_file); try { trace = TraceResult.readFrom(traceFile); } catch (IOException e) { System.err.format("Could not read the trace file \"%s\": %s%n", traceFile, e); System.exit(-1); } List<SlicingCriterion> sc = null; try { sc = SlicingCriterion.parseAll(slicingCriterionString, trace.getReadClasses()); } catch (IllegalArgumentException e) { System.err.println("Error parsing slicing criterion: " + e.getMessage()); System.exit(-1); } List<ThreadId> threads = trace.getThreads(); if (threads.size() == 0) { System.err.println("The trace file contains no tracing information."); System.exit(-1); } ThreadId tracing = null; for (ThreadId t : threads) { if (threadId == null) { if ("main".equals(t.getThreadName()) && (tracing == null || t.getJavaThreadId() < tracing.getJavaThreadId())) tracing = t; } else if (t.getJavaThreadId() == threadId.longValue()) { tracing = t; } } if (tracing == null) { System.err.println(threadId == null ? "Couldn't find the main thread." : "The thread you specified was not found."); System.exit(-1); } Slicer slicer = new Slicer(trace); boolean multithreaded = Runtime.getRuntime().availableProcessors() > 1; SliceInstructionsCollector collector = new SliceInstructionsCollector(); slicer.addSliceVisitor(collector); try { slicer.process(tracing, sc, multithreaded); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } Set<Instruction> slice = collector.getDynamicSlice(); Instruction[] sliceArray = slice.toArray(new Instruction[slice.size()]); Arrays.sort(sliceArray); System.out.println("The dynamic slice for criterion " + sc + ":"); for (Instruction insn : sliceArray) { String className = insn.getMethod().getReadClass().getName(); if (className.startsWith(Utils.focused_package)) { if (!checkedMap.containsKey(className)) { checkedMap.put(className, new HashSet<Instruction>()); } checkedMap.get(className).add(insn); // System.out.println(insn.getLineNumber()); } } } /** * calculate the slice, using Utils.trace_file as trace result file. * focuses the classes defined in Utils.focused_package. */ public static void calc() { clean(); String slicingCriterionString = TraceResult.getCriterion(); slice(slicingCriterionString); } /** * get checked lines by trace file and focused classes. * @param file_name * @param focusedClasses * @return a hashmap contains all checked lines with key is class name and value is set of lines. * @throws InterruptedException */ public static HashMap<String, HashSet<Instruction>> getCheckedLines() { if (checkedMap.isEmpty()) calc(); return checkedMap; } public static void printCheckedLines(HashMap<String, TreeSet<Integer>> checkedLines) { Iterator<String> it = checkedLines.keySet().iterator(); while (it.hasNext()) { String key = it.next(); System.out.println("checked lines in:" + key); TreeSet<Integer> value = checkedLines.get(key); for (Integer line : value) { System.out.println(line); } } } public static void printUncheckedLines(HashMap<String, TreeSet<Integer>> checkedLines) { Iterator<String> it = checkedLines.keySet().iterator(); while (it.hasNext()) { String key = it.next(); System.out.println("checked lines in:" + key); TreeSet<Integer> value = checkedLines.get(key); for (Integer line : value) { System.out.println(line); } } } /** * get unchecked map, based on covered map and checked map. * @return */ public static HashMap<String, HashSet<Instruction>> getUncheckedMap() { HashMap<String, HashSet<Instruction>> uncheckedMap = new HashMap<String, HashSet<Instruction>>(); HashMap<String, HashSet<Instruction>> covered = TraceResult.getCoveredInsts(); HashMap<String, HashSet<Instruction>> checked = getCheckedLines(); Iterator<String> keys = covered.keySet().iterator(); while (keys.hasNext()) { String key = keys.next(); HashSet<Instruction> unchecked = new HashSet<Instruction>(covered.get(key)); unchecked.removeAll(checked.get(key)); uncheckedMap.put(key, unchecked); } return uncheckedMap; } /** * select the last location that was not checked, and create new slice criterion for it. * remove the relative lines from unchecked lines, until all location are sliced. * @return the new created slice location for every class. */ public static HashMap<String, TreeSet<Long>> sliceForUnchecked() { System.out.println("Trying to add checks"); HashMap<String, TreeSet<Long>> sliceCreated = new HashMap<String, TreeSet<Long>>(); HashMap<String, HashSet<Instruction>> uncheckedMap = getUncheckedMap(); Iterator<String> it = uncheckedMap.keySet().iterator(); List<String> cris = new ArrayList<String>(); int crisNr = 0; while (it.hasNext()) { String key = it.next(); sliceCreated.put(key, new TreeSet<Long>()); HashSet<Instruction> insts = uncheckedMap.get(key); TreeSet<Integer> unchecked = new TreeSet<Integer>(); HashMap<Integer, String> critInfoMap = new HashMap<Integer, String>(); HashMap<Integer, HashSet<String>> varsMap = new HashMap<Integer, HashSet<String>>(); for (Instruction inst : insts) { if (inst.getType().equals(InstructionType.FIELD) || inst.getType().equals(InstructionType.VAR)) { unchecked.add(inst.getLineNumber()); if (!critInfoMap.containsKey(inst.getLineNumber())) { critInfoMap.put(inst.getLineNumber(), inst.getMethod().getReadClass().getName() + "." + inst.getMethod().getName()); } if (!varsMap.containsKey(inst.getLineNumber())) { varsMap.put(inst.getLineNumber(), new HashSet<String>()); } if (inst.getType().equals(InstructionType.FIELD)) { FieldInstruction fieldinst = (FieldInstruction) inst; varsMap.get(inst.getLineNumber()).add(fieldinst.getFieldName()); } else if (inst.getType().equals(InstructionType.VAR)) { VarInstruction varinst = (VarInstruction) inst; if (varinst.getOpcode() == Opcodes.DSTORE || varinst.getOpcode() == Opcodes.ASTORE || varinst.getOpcode() == Opcodes.LSTORE || varinst.getOpcode() == Opcodes.ISTORE || varinst.getOpcode() == Opcodes.FSTORE || varinst.getOpcode() == Opcodes.RET) { String varname = inst.getMethod().getLocalVariables()[varinst.getLocalVarIndex()] .getName(); varsMap.get(inst.getLineNumber()).add(varname); } } } } while (!unchecked.isEmpty()) { int last = unchecked.last(); String cri = critInfoMap.get(last) + ":" + last + ":*"; cris.add(cri); System.out.println(++crisNr + " new check(s) added!" + cri); unchecked.removeAll(sliceUnchecked(cri)); sliceCreated.get(key).add((long) last); unchecked.remove(last); } } System.out.println("Done!"); return sliceCreated; } public static void main(String[] args) { sliceForUnchecked(); } public static void previousMain(String[] args) throws InterruptedException { Options options = createOptions(); CommandLineParser parser = new GnuParser(); CommandLine cmdLine; try { cmdLine = parser.parse(options, args, true); } catch (ParseException e) { System.err.println("Error parsing the command line arguments: " + e.getMessage()); return; } if (cmdLine.hasOption('h')) { printHelp(options, System.out); System.exit(0); } String[] additionalArgs = cmdLine.getArgs(); if (additionalArgs.length != 2) { printHelp(options, System.err); System.exit(-1); } File traceFile = new File(additionalArgs[0]); String slicingCriterionString = additionalArgs[1]; Long threadId = null; if (cmdLine.hasOption('t')) { try { threadId = Long.parseLong(cmdLine.getOptionValue('t')); } catch (NumberFormatException e) { System.err.println("Illegal thread id: " + cmdLine.getOptionValue('t')); System.exit(-1); } } TraceResult trace; try { trace = TraceResult.readFrom(traceFile); } catch (IOException e) { System.err.format("Could not read the trace file \"%s\": %s%n", traceFile, e); System.exit(-1); return; } List<SlicingCriterion> sc = null; try { sc = SlicingCriterion.parseAll(slicingCriterionString, trace.getReadClasses()); } catch (IllegalArgumentException e) { System.err.println("Error parsing slicing criterion: " + e.getMessage()); System.exit(-1); return; } List<ThreadId> threads = trace.getThreads(); if (threads.size() == 0) { System.err.println("The trace file contains no tracing information."); System.exit(-1); } ThreadId tracing = null; for (ThreadId t : threads) { if (threadId == null) { if ("main".equals(t.getThreadName()) && (tracing == null || t.getJavaThreadId() < tracing.getJavaThreadId())) tracing = t; } else if (t.getJavaThreadId() == threadId.longValue()) { tracing = t; } } if (tracing == null) { System.err.println(threadId == null ? "Couldn't find the main thread." : "The thread you specified was not found."); System.exit(-1); return; } long startTime = System.nanoTime(); Slicer slicer = new Slicer(trace); if (cmdLine.hasOption("progress")) slicer.addProgressMonitor(new ConsoleProgressMonitor()); boolean multithreaded; if (cmdLine.hasOption("multithreaded")) { String multithreadedStr = cmdLine.getOptionValue("multithreaded"); multithreaded = ("1".equals(multithreadedStr) || "true".equals(multithreadedStr)); } else { multithreaded = Runtime.getRuntime().availableProcessors() > 1; } boolean warnUntracedMethods = cmdLine.hasOption("warn-untraced"); SliceInstructionsCollector collector = new SliceInstructionsCollector(); slicer.addSliceVisitor(collector); if (warnUntracedMethods) slicer.addUntracedCallVisitor(new PrintUniqueUntracedMethods()); slicer.process(tracing, sc, multithreaded); Set<Instruction> slice = collector.getDynamicSlice(); long endTime = System.nanoTime(); Instruction[] sliceArray = slice.toArray(new Instruction[slice.size()]); Arrays.sort(sliceArray); System.out.println("The dynamic slice for criterion " + sc + ":"); for (Instruction insn : sliceArray) { System.out.format((Locale) null, "%s.%s:%d %s%n", insn.getMethod().getReadClass().getName(), insn.getMethod().getName(), insn.getLineNumber(), insn.toString()); } System.out.format((Locale) null, "%nSlice consists of %d bytecode instructions.%n", sliceArray.length); System.out.format((Locale) null, "Computation took %.2f seconds.%n", 1e-9 * (endTime - startTime)); } public void addProgressMonitor(ProgressMonitor progressMonitor) { this.progressMonitors.add(progressMonitor); } public void addSliceVisitor(SliceVisitor sliceVisitor) { this.sliceVisitors.add(sliceVisitor); } public void addUntracedCallVisitor(UntracedCallVisitor untracedCallVisitor) { this.untracedCallVisitors.add(untracedCallVisitor); } public void process(ThreadId threadId, final List<SlicingCriterion> sc, boolean multithreaded) throws InterruptedException { DependencesExtractor<SlicerInstance> depExtractor = DependencesExtractor.forTrace(this.trace, SlicerInstanceFactory.instance); for (ProgressMonitor mon : this.progressMonitors) depExtractor.addProgressMonitor(mon); VisitorCapability[] capabilities = { VisitorCapability.CONTROL_DEPENDENCES, VisitorCapability.DATA_DEPENDENCES_READ_AFTER_WRITE, VisitorCapability.INSTRUCTION_EXECUTIONS, VisitorCapability.METHOD_ENTRY_LEAVE, VisitorCapability.CONTROL_DEPENDENCES }; if (this.untracedCallVisitors.size() > 0) capabilities[capabilities.length - 1] = VisitorCapability.UNTRACED_METHOD_CALLS; final List<SliceVisitor> sliceVisitors0 = Slicer.this.sliceVisitors; final List<UntracedCallVisitor> untracedCallVisitors0 = Slicer.this.untracedCallVisitors; depExtractor.registerVisitor(new DependencesVisitorAdapter<SlicerInstance>() { private final List<SlicingCriterionInstance> slicingCritInst = instantiateSlicingCriteria(sc); @SuppressWarnings("unchecked") private IntegerMap<Object>[] interestingLocalVariables = (IntegerMap<Object>[]) new IntegerMap<?>[0]; private long[] critOccurenceNumbers = new long[2]; // 0 if not in a criterion private final SliceVisitor[] sliceVisitorsArray = sliceVisitors0 .toArray(new SliceVisitor[sliceVisitors0.size()]); private final UntracedCallVisitor[] untracedCallsVisitorsArray = untracedCallVisitors0 .toArray(new UntracedCallVisitor[untracedCallVisitors0.size()]); private ReadMethod enteredMethod; private List<SlicingCriterionInstance> instantiateSlicingCriteria(List<SlicingCriterion> criteria) { if (criteria.isEmpty()) return Collections.emptyList(); else if (criteria.size() == 1) return Collections.singletonList(criteria.get(0).getInstance()); else { List<SlicingCriterionInstance> instances = new ArrayList<SlicingCriterionInstance>( criteria.size()); for (SlicingCriterion crit : criteria) instances.add(crit.getInstance()); return instances; } } @Override public void visitInstructionExecution(SlicerInstance instance) { int stackDepth = instance.getStackDepth(); if (this.critOccurenceNumbers.length <= stackDepth) { long[] newCritOccurenceNumbers = new long[2 * Math.max(this.critOccurenceNumbers.length, stackDepth)]; System.arraycopy(this.critOccurenceNumbers, 0, newCritOccurenceNumbers, 0, this.critOccurenceNumbers.length); this.critOccurenceNumbers = newCritOccurenceNumbers; } Instruction instruction = instance.getInstruction(); for (SlicingCriterionInstance crit : this.slicingCritInst) { if (crit.matches(instance)) { this.critOccurenceNumbers[stackDepth] = crit.getOccurenceNumber(); assert (this.critOccurenceNumbers[stackDepth] > 0); // for each criterion, there are three cases: // - track all data read in this line // - track a given set of local variables // - track the control dependences of this instruction // only in the last case, the instructions from that line are added to the dynamic slice if (crit.matchAllData()) { instance.allDataInteresting = true; instance.onlyIfAfterCriterion = true; instance.onDynamicSlice = true; // it's not really on the dynamic slice, but we have to set this instance.criterionDistance = 0; } else { if (crit.hasLocalVariables()) { if (this.interestingLocalVariables.length <= stackDepth) { @SuppressWarnings("unchecked") IntegerMap<Object>[] newInterestingLocalVariables = (IntegerMap<Object>[]) new IntegerMap<?>[Math .max(stackDepth + 1, this.interestingLocalVariables.length * 3 / 2)]; System.arraycopy(this.interestingLocalVariables, 0, newInterestingLocalVariables, 0, this.interestingLocalVariables.length); this.interestingLocalVariables = newInterestingLocalVariables; } List<LocalVariable> localVariables = crit.getLocalVariables(); if (this.interestingLocalVariables[stackDepth] == null) this.interestingLocalVariables[stackDepth] = new IntegerMap<Object>( localVariables.size() * 4 / 3 + 1); for (LocalVariable i : localVariables) this.interestingLocalVariables[stackDepth].put(i.getIndex(), null); } else { Instruction insn = instruction; if (insn.getType() != InstructionType.LABEL) for (SliceVisitor vis : this.sliceVisitorsArray) vis.visitMatchedInstance(instance); instance.onDynamicSlice = true; instance.criterionDistance = 0; } } } else if (this.critOccurenceNumbers[stackDepth] != 0) { this.critOccurenceNumbers[stackDepth] = 0; } } if (this.interestingLocalVariables.length > stackDepth && this.interestingLocalVariables[stackDepth] != null) { switch (instruction.getOpcode()) { case Opcodes.ISTORE: case Opcodes.ASTORE: case Opcodes.LSTORE: case Opcodes.FSTORE: case Opcodes.DSTORE: VarInstruction varInsn = (VarInstruction) instruction; if (this.interestingLocalVariables[stackDepth].containsKey(varInsn.getLocalVarIndex())) { this.interestingLocalVariables[stackDepth].remove(varInsn.getLocalVarIndex()); if (this.interestingLocalVariables[stackDepth].isEmpty()) this.interestingLocalVariables[stackDepth] = null; for (SliceVisitor vis : this.sliceVisitorsArray) vis.visitMatchedInstance(instance); instance.onDynamicSlice = true; // and we want to know where the data comes from... instance.allDataInteresting = true; instance.criterionDistance = 0; } break; case Opcodes.INVOKEINTERFACE: case Opcodes.INVOKESPECIAL: case Opcodes.INVOKESTATIC: case Opcodes.INVOKEVIRTUAL: if (this.enteredMethod != null) { MethodInvocationInstruction mtdInvInsn = (MethodInvocationInstruction) instruction; int paramCount = instruction.getOpcode() == INVOKESTATIC ? 0 : 1; for (int param = mtdInvInsn.getParameterCount() - 1; param >= 0; --param) paramCount += mtdInvInsn.parameterIsLong(param) ? 2 : 1; boolean enteredMethodMatches = this.enteredMethod.getName() .equals(mtdInvInsn.getInvokedMethodName()) && this.enteredMethod.getDesc().equals(mtdInvInsn.getInvokedMethodDesc()); if (enteredMethodMatches) { boolean localVarsMatched = false; for (int varNr = 0; varNr < paramCount; ++varNr) { if (this.interestingLocalVariables[stackDepth].containsKey(varNr)) { this.interestingLocalVariables[stackDepth].remove(varNr); if (this.interestingLocalVariables[stackDepth].isEmpty()) this.interestingLocalVariables[stackDepth] = null; localVarsMatched = true; instance.onDynamicSlice = true; // and we want to know where the data comes from... // TODO instance.allDataInteresting = true; instance.criterionDistance = 0; } } if (localVarsMatched) for (SliceVisitor vis : this.sliceVisitorsArray) vis.visitMatchedInstance(instance); } } } } this.enteredMethod = null; } @Override public void visitControlDependence(SlicerInstance from, SlicerInstance to) { if (from.onDynamicSlice) { Instruction insn = to.getInstruction(); if (insn.getType() == InstructionType.LABEL || insn.getOpcode() == Opcodes.GOTO) { if (to.predecessors == null) to.predecessors = Collections.singleton(from); else { if (to.predecessors.size() == 1) to.predecessors = new HashSet<SlicerInstance>(to.predecessors); to.predecessors.add(from); } if (from.criterionDistance < to.criterionDistance) to.criterionDistance = from.criterionDistance; } else if (from.predecessors != null) { assert (!from.predecessors.isEmpty()); for (SlicerInstance pred : from.predecessors) { int distance = pred.criterionDistance + 1; delegateControlSliceDependence(pred, to, distance); if (distance < to.criterionDistance) to.criterionDistance = distance; } } else { int distance = from.criterionDistance + 1; delegateControlSliceDependence(from, to, distance); if (distance < to.criterionDistance) to.criterionDistance = distance; } to.onDynamicSlice = true; } } private void delegateControlSliceDependence(SlicerInstance from, SlicerInstance to, int distance) { for (SliceVisitor vis : this.sliceVisitorsArray) vis.visitSliceDependence(from, to, null, distance); // since "to" controls the execution of "from", we want to track all data dependences of "to" // to find out why it took this decision // exception: method invocations; here we only want to track why the method was executed, // but not the data that it consumed // important to check that "from" comes from inside the method which is called by "from" boolean calledMethodDependence = false; if (to.getInstruction().getType() == InstructionType.METHODINVOCATION) { MethodInvocationInstruction mtdInv = (MethodInvocationInstruction) to.getInstruction(); ReadMethod calledMethod = from.getInstruction().getMethod(); if (mtdInv.getInvokedMethodName().equals(calledMethod.getName()) && mtdInv.getInvokedMethodDesc().equals(calledMethod.getDesc())) { calledMethodDependence = true; } } if (!calledMethodDependence) { to.allDataInteresting = true; } } @Override public void visitDataDependence(SlicerInstance from, SlicerInstance to, Collection<? extends Variable> fromVars, Variable toVar, DataDependenceType type) throws InterruptedException { assert type == DataDependenceType.READ_AFTER_WRITE; if (from.onDynamicSlice && // from must definitively be on the dynamic slice ((from.allDataInteresting && (!from.onlyIfAfterCriterion || this.critOccurenceNumbers[to.getStackDepth()] == 0)) || // and either we want to track all data dependencies (from.interestingVariable != null && ( // or (if the interestingVariable is set) ... from.interestingVariable.equals(toVar) || // the interestingVariable must be the one we are just visiting (from.moreInterestingVariables != null && from.moreInterestingVariables.contains(toVar)))))) { // or it must be in the set of more variables Instruction insn = to.getInstruction(); assert insn.getType() != InstructionType.LABEL; if (from.onlyIfAfterCriterion) { to.criterionDistance = 0; for (SliceVisitor vis : this.sliceVisitorsArray) vis.visitMatchedInstance(to); } else { int distance = from.criterionDistance + 1; if (distance < to.criterionDistance) to.criterionDistance = distance; for (SliceVisitor vis : this.sliceVisitorsArray) vis.visitSliceDependence(from, to, toVar, distance); } if (!fromVars.isEmpty()) { Iterator<? extends Variable> varIt = fromVars.iterator(); assert varIt .hasNext() : "Iterator of a non-empty collection should have at least one element"; Variable first = varIt.next(); if (to.interestingVariable == null || to.interestingVariable.equals(first)) { to.interestingVariable = first; first = varIt.hasNext() ? varIt.next() : null; } if (first != null) { if (to.moreInterestingVariables == null) to.moreInterestingVariables = new HashSet<Variable>(8); to.moreInterestingVariables.add(first); while (varIt.hasNext()) to.moreInterestingVariables.add(varIt.next()); } } to.onDynamicSlice = true; } } @Override public void visitMethodLeave(ReadMethod method, int stackDepth) throws InterruptedException { if (this.interestingLocalVariables.length > stackDepth && this.interestingLocalVariables[stackDepth] != null) { this.interestingLocalVariables[stackDepth] = null; } } @Override public void visitMethodEntry(ReadMethod method, int stackDepth) throws InterruptedException { if (this.interestingLocalVariables.length > stackDepth && this.interestingLocalVariables[stackDepth] != null) { this.enteredMethod = method; this.interestingLocalVariables[stackDepth] = null; } } @Override public void visitUntracedMethodCall(SlicerInstance instrInstance) throws InterruptedException { for (UntracedCallVisitor vis : this.untracedCallsVisitorsArray) vis.visitUntracedMethodCall(instrInstance); } }, capabilities); depExtractor.processBackwardTrace(threadId, multithreaded); } @SuppressWarnings("static-access") private static Options createOptions() { Options options = new Options(); options.addOption(OptionBuilder.isRequired(false).withArgName("threadid").hasArg(true) .withDescription("thread id to select for slicing (default: main thread)").withLongOpt("threadid") .create('t')); options.addOption(OptionBuilder.isRequired(false).hasArg(false) .withDescription("show progress while computing the dynamic slice").withLongOpt("progress") .create('p')); options.addOption(OptionBuilder.isRequired(false).hasArg(false).withDescription("print this help and exit") .withLongOpt("help").create('h')); options.addOption(OptionBuilder.isRequired(false).hasArg(true).withArgName("value").withDescription( "process the trace in a multithreaded way (pass 'true' or '1' to enable, anything else to disable). Default is true iff we have more than one processor") .withLongOpt("multithreaded").create('m')); options.addOption(OptionBuilder.isRequired(false).hasArg(false) .withDescription("warn once for each method which is called but not traced") .withLongOpt("warn-untraced").create('u')); return options; } private static void printHelp(Options options, PrintStream out) { out.println("Usage: " + Slicer.class.getSimpleName() + " [<options>] <file> <slicing criterion>"); out.println("where <file> is the input trace file"); out.println(" <slicing criterion> has the form <loc>[(<occ>)]:<var>[,<loc>[(<occ>)]:<var>]*"); out.println(" <options> may be one or more of"); HelpFormatter formatter = new HelpFormatter(); PrintWriter pw = new PrintWriter(out, true); formatter.printOptions(pw, 120, options, 5, 3); } }