src/main/java/com/android/tools/r8/graph/DexDebugEventBuilder.java - r8 - Git at Google

 // Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 package com.android.tools.r8.graph;

 import static com.android.tools.r8.utils.DexDebugUtils.verifySetPositionFramesFollowedByDefaultEvent;

 import com.android.tools.r8.dex.Constants;
 import com.android.tools.r8.graph.DexDebugEvent.Default;
 import com.android.tools.r8.graph.DexDebugEvent.StartLocal;
 import com.android.tools.r8.graph.DexDebugInfo.EventBasedDebugInfo;
 import com.android.tools.r8.ir.code.Argument;
 import com.android.tools.r8.ir.code.DebugLocalsChange;
 import com.android.tools.r8.ir.code.IRCode;
 import com.android.tools.r8.ir.code.Instruction;
 import com.android.tools.r8.ir.code.Position;
 import com.android.tools.r8.ir.code.Position.SourcePosition;
 import com.android.tools.r8.utils.InternalOptions;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMap.Entry;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceMaps;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceSortedMap;
 import java.util.ArrayList;
 import java.util.List;

 /**
  * Builder for constructing a list of debug events suitable for DexDebugInfo.
  *
  * This builder is intended to be very pedantic and ensure a well-formed structure of the resulting
  * event stream.
  */
 public class DexDebugEventBuilder {

   public static final int NO_PC_INFO = -1;
   private static final int NO_LINE_INFO = -1;

   private final AppView<?> appView;
   private final DexEncodedMethod method;
   private final DexItemFactory factory;
   private final InternalOptions options;

   // In order list of non-this argument locals.
   private ArrayList<DebugLocalInfo> arguments;

   // Mapping from register to the last known local in that register (See DBG_RESTART_LOCAL).
   private Int2ReferenceMap<DebugLocalInfo> lastKnownLocals;

   // Mapping from register to local for currently open/visible locals.
   private Int2ReferenceMap<DebugLocalInfo> pendingLocals = null;

   // Conservative pending-state of locals to avoid some equality checks on locals.
   // pendingLocalChanges == true ==> localsEqual(emittedLocals, pendingLocals).
   private boolean pendingLocalChanges = false;

   // State of pc, line, file and locals in the emitted event stream.
   private int emittedPc = NO_PC_INFO;
   private Position emittedPosition = Position.none();
   private Int2ReferenceMap<DebugLocalInfo> emittedLocals;
   private final boolean isComposing;

   // Emitted events.
   private final List<DexDebugEvent> events = new ArrayList<>();

   // Initial known line for the method.
   private int startLine = NO_LINE_INFO;

   public DexDebugEventBuilder(AppView<?> appView, IRCode code) {
     this.appView = appView;
     method = code.context().getDefinition();
     factory = appView.dexItemFactory();
     options = appView.options();
     isComposing =
         options.mappingComposeOptions().enableExperimentalMappingComposition
             && appView.appInfo().app().getProguardMap() != null;
   }

   /** Add events at pc for instruction. */
   public void add(int pc, int postPc, Instruction instruction, ProgramMethod context) {
     boolean isBlockEntry = instruction.getBlock().entry() == instruction;
     boolean isBlockExit = instruction.getBlock().exit() == instruction;

     // Initialize locals state on block entry.
     if (isBlockEntry) {
       updateBlockEntry(instruction);
     }
     assert pendingLocals != null;

     Position position = instruction.getPosition();
     boolean pcAdvancing = pc != postPc;

     // In debug mode check that all non-nop instructions have positions.
     assert instruction.verifyValidPositionInfo(options.debug);

     if (instruction.isArgument()) {
       startArgument(instruction.asArgument());
     } else if (instruction.isDebugLocalsChange()) {
       updateLocals(instruction.asDebugLocalsChange());
     } else if (pcAdvancing) {
       if (!position.isNone() && !position.equals(emittedPosition)) {
         if (options.debug
             || instruction.instructionInstanceCanThrow(appView, context)
             || isComposing) {
           emitDebugPosition(pc, position);
         }
       }
       if (emittedPc != pc) {
         emitLocalChanges(pc);
       }
     }

     if (isBlockExit) {
       // If this is the end of the block clear out the pending state.
       pendingLocals = null;
       pendingLocalChanges = false;
     }
   }

   /** Build the resulting DexDebugInfo object. */
   public DexDebugInfo build() {
     assert pendingLocals == null;
     assert !pendingLocalChanges;
     if (startLine == NO_LINE_INFO) {
       return null;
     }
     DexString[] params = new DexString[method.getReference().getArity()];
     if (arguments != null) {
       assert params.length == arguments.size();
       for (int i = 0; i < arguments.size(); i++) {
         DebugLocalInfo local = arguments.get(i);
         params[i] = (local == null || local.signature != null) ? null : local.name;
       }
     }
     assert verifySetPositionFramesFollowedByDefaultEvent(events);
     return new EventBasedDebugInfo(startLine, params, events.toArray(DexDebugEvent.EMPTY_ARRAY));
   }

   private void updateBlockEntry(Instruction instruction) {
     assert pendingLocals == null;
     assert !pendingLocalChanges;
     Int2ReferenceMap<DebugLocalInfo> locals = instruction.getBlock().getLocalsAtEntry();
     if (locals == null) {
       pendingLocals = Int2ReferenceMaps.emptyMap();
     } else {
       pendingLocals = new Int2ReferenceOpenHashMap<>(locals);
       pendingLocalChanges = true;
     }
     if (emittedLocals == null) {
       initialize(locals);
     }
   }

   private void initialize(Int2ReferenceMap<DebugLocalInfo> locals) {
     assert arguments == null;
     assert emittedLocals == null;
     assert lastKnownLocals == null;
     assert startLine == NO_LINE_INFO;
     if (locals == null) {
       emittedLocals = Int2ReferenceMaps.emptyMap();
       lastKnownLocals = Int2ReferenceMaps.emptyMap();
       return;
     }
     // Implicitly open all unparameterized arguments.
     emittedLocals = new Int2ReferenceOpenHashMap<>();
     for (Entry<DebugLocalInfo> entry : locals.int2ReferenceEntrySet()) {
       if (entry.getValue().signature == null) {
         emittedLocals.put(entry.getIntKey(), entry.getValue());
       } else if (options.testing.emitDebugLocalStartBeforeDefaultEvent) {
         events.add(new StartLocal(entry.getIntKey(), entry.getValue()));
         emittedLocals.put(entry.getIntKey(), entry.getValue());
       }
     }
     lastKnownLocals = new Int2ReferenceOpenHashMap<>(emittedLocals);
   }

   private void startArgument(Argument argument) {
     if (arguments == null) {
       arguments = new ArrayList<>(method.getReference().getArity());
     }
     if (!argument.outValue().isThis()) {
       arguments.add(argument.getLocalInfo());
     }
   }

   private void updateLocals(DebugLocalsChange change) {
     pendingLocalChanges = true;
     change.apply(pendingLocals);
   }

   private boolean localsChanged() {
     if (!pendingLocalChanges) {
       return false;
     }
     pendingLocalChanges = !DebugLocalInfo.localsInfoMapsEqual(emittedLocals, pendingLocals);
     return pendingLocalChanges;
   }

   private void emitDebugPosition(int pc, Position position) {
     assert !position.equals(emittedPosition);
     if (startLine == NO_LINE_INFO) {
       assert emittedPosition.isNone();
       if (position.isSyntheticPosition() && !position.hasCallerPosition()) {
         // Ignore synthetic positions prior to any actual position.
         // We do need to preserve synthetic position establishing the stack frame for inlined
         // methods.
         return;
       }
       startLine = position.getLine();
       emittedPosition =
           SourcePosition.builder()
               .setLine(position.getLine())
               .setMethod(position.getOutermostCaller().getMethod())
               .build();
     }
     assert emittedPc != pc;
     int previousPc = emittedPc == NO_PC_INFO ? 0 : emittedPc;
     emitAdvancementEvents(previousPc, emittedPosition, pc, position, events, factory, false);
     emittedPc = pc;
     emittedPosition = position;
     if (localsChanged()) {
       emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
       assert DebugLocalInfo.localsInfoMapsEqual(emittedLocals, pendingLocals);
     }
     pendingLocalChanges = false;
   }

   private void emitLocalChanges(int pc) {
     // If pc advanced since the locals changed and locals indeed have changed, emit the changes.
     if (localsChanged()) {
       assert emittedPc != pc;
       int pcDelta = emittedPc == NO_PC_INFO ? pc : pc - emittedPc;
       assert pcDelta > 0 || emittedPc == NO_PC_INFO;
       if (pcDelta > 0) {
         events.add(factory.createAdvancePC(pcDelta));
       }
       emittedPc = pc;
       emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
       pendingLocalChanges = false;
       assert DebugLocalInfo.localsInfoMapsEqual(emittedLocals, pendingLocals);
     }
   }

   @SuppressWarnings("ReferenceEquality")
   public static void emitAdvancementEvents(
       int previousPc,
       Position previousPosition,
       int nextPc,
       Position nextPosition,
       List<DexDebugEvent> events,
       DexItemFactory factory,
       boolean optimizingLineNumbers) {
     assert previousPc >= 0;
     int pcDelta = nextPc - previousPc;
     assert !previousPosition.isNone() || nextPosition.isNone();
     assert nextPosition.isNone() || nextPosition.getLine() >= 0;
     int lineDelta = nextPosition.isNone() ? 0 : nextPosition.getLine() - previousPosition.getLine();
     assert pcDelta >= 0;
     if (nextPosition.getFile() != previousPosition.getFile()) {
       events.add(factory.createSetFile(nextPosition.getFile()));
     }
     // The LineNumberOptimizer maps new positions based on the outer most caller with
     // callerPosition == null.
     assert nextPosition.hasCallerPosition()
         || previousPosition.hasCallerPosition()
         || nextPosition.getMethod() == previousPosition.getMethod()
         || optimizingLineNumbers;
     boolean isNewPosition =
         nextPosition.getCallerPosition() != previousPosition.getCallerPosition()
             || nextPosition.getMethod() != previousPosition.getMethod();
     boolean isOutline = nextPosition.isOutline();
     boolean isOutlineCallerWithInfo =
         nextPosition.isOutlineCaller()
             && nextPosition.getOutlineCallee() != null
             && !nextPosition.getOutlinePositions().isEmpty();
     boolean isNoLongerOutlineCaller =
         previousPosition.isOutlineCaller() && !nextPosition.isOutlineCaller();
     if (isNewPosition || isOutline || isOutlineCallerWithInfo || isNoLongerOutlineCaller) {
       events.add(factory.createPositionFrame(nextPosition));
     }
     addDefaultEventWithAdvancePcIfNecessary(lineDelta, pcDelta, events, factory);
   }

   public static void addDefaultEventWithAdvancePcIfNecessary(
       int lineDelta, int pcDelta, List<DexDebugEvent> events, DexItemFactory factory) {
     if (lineDelta < Constants.DBG_LINE_BASE
         || lineDelta - Constants.DBG_LINE_BASE >= Constants.DBG_LINE_RANGE) {
       events.add(factory.createAdvanceLine(lineDelta));
       // TODO(herhut): To be super clever, encode only the part that is above limit.
       lineDelta = 0;
     }
     int specialOpcode = Default.computeSpecialOpcode(lineDelta, pcDelta);
     if (specialOpcode > Constants.DBG_LAST_SPECIAL) {
       events.add(factory.createAdvancePC(pcDelta));
       // TODO(herhut): To be super clever, encode only the part that is above limit.
       specialOpcode = Default.computeSpecialOpcode(lineDelta, 0);
     }
     assert specialOpcode >= Constants.DBG_FIRST_SPECIAL;
     assert specialOpcode <= Constants.DBG_LAST_SPECIAL;
     events.add(factory.createDefault(specialOpcode));
   }

   @SuppressWarnings("ReferenceEquality")
   private static void emitLocalChangeEvents(
       Int2ReferenceMap<DebugLocalInfo> previousLocals,
       Int2ReferenceMap<DebugLocalInfo> nextLocals,
       Int2ReferenceMap<DebugLocalInfo> lastKnownLocals,
       List<DexDebugEvent> events,
       DexItemFactory factory) {
     Int2ReferenceSortedMap<DebugLocalInfo> ending =
         DebugLocalInfo.endingLocals(previousLocals, nextLocals);
     Int2ReferenceSortedMap<DebugLocalInfo> starting =
         DebugLocalInfo.startingLocals(previousLocals, nextLocals);
     assert !ending.isEmpty() || !starting.isEmpty();
     for (Entry<DebugLocalInfo> end : ending.int2ReferenceEntrySet()) {
       int register = end.getIntKey();
       if (!starting.containsKey(register)) {
         previousLocals.remove(register);
         events.add(factory.createEndLocal(register));
       }
     }
     for (Entry<DebugLocalInfo> start : starting.int2ReferenceEntrySet()) {
       int register = start.getIntKey();
       DebugLocalInfo local = start.getValue();
       previousLocals.put(register, local);
       if (lastKnownLocals.get(register) == local) {
         events.add(factory.createRestartLocal(register));
       } else {
         events.add(new StartLocal(register, local));
         lastKnownLocals.put(register, local);
       }
     }
   }
 }
	// Copyright (c) 2017, the R8 project authors. Please see the AUTHORS file
	// for details. All rights reserved. Use of this source code is governed by a
	// BSD-style license that can be found in the LICENSE file.
	package com.android.tools.r8.graph;

	import static com.android.tools.r8.utils.DexDebugUtils.verifySetPositionFramesFollowedByDefaultEvent;

	import com.android.tools.r8.dex.Constants;
	import com.android.tools.r8.graph.DexDebugEvent.Default;
	import com.android.tools.r8.graph.DexDebugEvent.StartLocal;
	import com.android.tools.r8.graph.DexDebugInfo.EventBasedDebugInfo;
	import com.android.tools.r8.ir.code.Argument;
	import com.android.tools.r8.ir.code.DebugLocalsChange;
	import com.android.tools.r8.ir.code.IRCode;
	import com.android.tools.r8.ir.code.Instruction;
	import com.android.tools.r8.ir.code.Position;
	import com.android.tools.r8.ir.code.Position.SourcePosition;
	import com.android.tools.r8.utils.InternalOptions;
	import it.unimi.dsi.fastutil.ints.Int2ReferenceMap;
	import it.unimi.dsi.fastutil.ints.Int2ReferenceMap.Entry;
	import it.unimi.dsi.fastutil.ints.Int2ReferenceMaps;
	import it.unimi.dsi.fastutil.ints.Int2ReferenceOpenHashMap;
	import it.unimi.dsi.fastutil.ints.Int2ReferenceSortedMap;
	import java.util.ArrayList;
	import java.util.List;

	/**
	* Builder for constructing a list of debug events suitable for DexDebugInfo.
	*
	* This builder is intended to be very pedantic and ensure a well-formed structure of the resulting
	* event stream.
	*/
	public class DexDebugEventBuilder {

	public static final int NO_PC_INFO = -1;
	private static final int NO_LINE_INFO = -1;

	private final AppView<?> appView;
	private final DexEncodedMethod method;
	private final DexItemFactory factory;
	private final InternalOptions options;

	// In order list of non-this argument locals.
	private ArrayList<DebugLocalInfo> arguments;

	// Mapping from register to the last known local in that register (See DBG_RESTART_LOCAL).
	private Int2ReferenceMap<DebugLocalInfo> lastKnownLocals;

	// Mapping from register to local for currently open/visible locals.
	private Int2ReferenceMap<DebugLocalInfo> pendingLocals = null;

	// Conservative pending-state of locals to avoid some equality checks on locals.
	// pendingLocalChanges == true ==> localsEqual(emittedLocals, pendingLocals).
	private boolean pendingLocalChanges = false;

	// State of pc, line, file and locals in the emitted event stream.
	private int emittedPc = NO_PC_INFO;
	private Position emittedPosition = Position.none();
	private Int2ReferenceMap<DebugLocalInfo> emittedLocals;
	private final boolean isComposing;

	// Emitted events.
	private final List<DexDebugEvent> events = new ArrayList<>();

	// Initial known line for the method.
	private int startLine = NO_LINE_INFO;

	public DexDebugEventBuilder(AppView<?> appView, IRCode code) {
	this.appView = appView;
	method = code.context().getDefinition();
	factory = appView.dexItemFactory();
	options = appView.options();
	isComposing =
	options.mappingComposeOptions().enableExperimentalMappingComposition
	&& appView.appInfo().app().getProguardMap() != null;
	}

	/** Add events at pc for instruction. */
	public void add(int pc, int postPc, Instruction instruction, ProgramMethod context) {
	boolean isBlockEntry = instruction.getBlock().entry() == instruction;
	boolean isBlockExit = instruction.getBlock().exit() == instruction;

	// Initialize locals state on block entry.
	if (isBlockEntry) {
	updateBlockEntry(instruction);
	}
	assert pendingLocals != null;

	Position position = instruction.getPosition();
	boolean pcAdvancing = pc != postPc;

	// In debug mode check that all non-nop instructions have positions.
	assert instruction.verifyValidPositionInfo(options.debug);

	if (instruction.isArgument()) {
	startArgument(instruction.asArgument());
	} else if (instruction.isDebugLocalsChange()) {
	updateLocals(instruction.asDebugLocalsChange());
	} else if (pcAdvancing) {
	if (!position.isNone() && !position.equals(emittedPosition)) {
	if (options.debug
	\|\| instruction.instructionInstanceCanThrow(appView, context)
	\|\| isComposing) {
	emitDebugPosition(pc, position);
	}
	}
	if (emittedPc != pc) {
	emitLocalChanges(pc);
	}
	}

	if (isBlockExit) {
	// If this is the end of the block clear out the pending state.
	pendingLocals = null;
	pendingLocalChanges = false;
	}
	}

	/** Build the resulting DexDebugInfo object. */
	public DexDebugInfo build() {
	assert pendingLocals == null;
	assert !pendingLocalChanges;
	if (startLine == NO_LINE_INFO) {
	return null;
	}
	DexString[] params = new DexString[method.getReference().getArity()];
	if (arguments != null) {
	assert params.length == arguments.size();
	for (int i = 0; i < arguments.size(); i++) {
	DebugLocalInfo local = arguments.get(i);
	params[i] = (local == null \|\| local.signature != null) ? null : local.name;
	}
	}
	assert verifySetPositionFramesFollowedByDefaultEvent(events);
	return new EventBasedDebugInfo(startLine, params, events.toArray(DexDebugEvent.EMPTY_ARRAY));
	}

	private void updateBlockEntry(Instruction instruction) {
	assert pendingLocals == null;
	assert !pendingLocalChanges;
	Int2ReferenceMap<DebugLocalInfo> locals = instruction.getBlock().getLocalsAtEntry();
	if (locals == null) {
	pendingLocals = Int2ReferenceMaps.emptyMap();
	} else {
	pendingLocals = new Int2ReferenceOpenHashMap<>(locals);
	pendingLocalChanges = true;
	}
	if (emittedLocals == null) {
	initialize(locals);
	}
	}

	private void initialize(Int2ReferenceMap<DebugLocalInfo> locals) {
	assert arguments == null;
	assert emittedLocals == null;
	assert lastKnownLocals == null;
	assert startLine == NO_LINE_INFO;
	if (locals == null) {
	emittedLocals = Int2ReferenceMaps.emptyMap();
	lastKnownLocals = Int2ReferenceMaps.emptyMap();
	return;
	}
	// Implicitly open all unparameterized arguments.
	emittedLocals = new Int2ReferenceOpenHashMap<>();
	for (Entry<DebugLocalInfo> entry : locals.int2ReferenceEntrySet()) {
	if (entry.getValue().signature == null) {
	emittedLocals.put(entry.getIntKey(), entry.getValue());
	} else if (options.testing.emitDebugLocalStartBeforeDefaultEvent) {
	events.add(new StartLocal(entry.getIntKey(), entry.getValue()));
	emittedLocals.put(entry.getIntKey(), entry.getValue());
	}
	}
	lastKnownLocals = new Int2ReferenceOpenHashMap<>(emittedLocals);
	}

	private void startArgument(Argument argument) {
	if (arguments == null) {
	arguments = new ArrayList<>(method.getReference().getArity());
	}
	if (!argument.outValue().isThis()) {
	arguments.add(argument.getLocalInfo());
	}
	}

	private void updateLocals(DebugLocalsChange change) {
	pendingLocalChanges = true;
	change.apply(pendingLocals);
	}

	private boolean localsChanged() {
	if (!pendingLocalChanges) {
	return false;
	}
	pendingLocalChanges = !DebugLocalInfo.localsInfoMapsEqual(emittedLocals, pendingLocals);
	return pendingLocalChanges;
	}

	private void emitDebugPosition(int pc, Position position) {
	assert !position.equals(emittedPosition);
	if (startLine == NO_LINE_INFO) {
	assert emittedPosition.isNone();
	if (position.isSyntheticPosition() && !position.hasCallerPosition()) {
	// Ignore synthetic positions prior to any actual position.
	// We do need to preserve synthetic position establishing the stack frame for inlined
	// methods.
	return;
	}
	startLine = position.getLine();
	emittedPosition =
	SourcePosition.builder()
	.setLine(position.getLine())
	.setMethod(position.getOutermostCaller().getMethod())
	.build();
	}
	assert emittedPc != pc;
	int previousPc = emittedPc == NO_PC_INFO ? 0 : emittedPc;
	emitAdvancementEvents(previousPc, emittedPosition, pc, position, events, factory, false);
	emittedPc = pc;
	emittedPosition = position;
	if (localsChanged()) {
	emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
	assert DebugLocalInfo.localsInfoMapsEqual(emittedLocals, pendingLocals);
	}
	pendingLocalChanges = false;
	}

	private void emitLocalChanges(int pc) {
	// If pc advanced since the locals changed and locals indeed have changed, emit the changes.
	if (localsChanged()) {
	assert emittedPc != pc;
	int pcDelta = emittedPc == NO_PC_INFO ? pc : pc - emittedPc;
	assert pcDelta > 0 \|\| emittedPc == NO_PC_INFO;
	if (pcDelta > 0) {
	events.add(factory.createAdvancePC(pcDelta));
	}
	emittedPc = pc;
	emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
	pendingLocalChanges = false;
	assert DebugLocalInfo.localsInfoMapsEqual(emittedLocals, pendingLocals);
	}
	}

	@SuppressWarnings("ReferenceEquality")
	public static void emitAdvancementEvents(
	int previousPc,
	Position previousPosition,
	int nextPc,
	Position nextPosition,
	List<DexDebugEvent> events,
	DexItemFactory factory,
	boolean optimizingLineNumbers) {
	assert previousPc >= 0;
	int pcDelta = nextPc - previousPc;
	assert !previousPosition.isNone() \|\| nextPosition.isNone();
	assert nextPosition.isNone() \|\| nextPosition.getLine() >= 0;
	int lineDelta = nextPosition.isNone() ? 0 : nextPosition.getLine() - previousPosition.getLine();
	assert pcDelta >= 0;
	if (nextPosition.getFile() != previousPosition.getFile()) {
	events.add(factory.createSetFile(nextPosition.getFile()));
	}
	// The LineNumberOptimizer maps new positions based on the outer most caller with
	// callerPosition == null.
	assert nextPosition.hasCallerPosition()
	\|\| previousPosition.hasCallerPosition()
	\|\| nextPosition.getMethod() == previousPosition.getMethod()
	\|\| optimizingLineNumbers;
	boolean isNewPosition =
	nextPosition.getCallerPosition() != previousPosition.getCallerPosition()
	\|\| nextPosition.getMethod() != previousPosition.getMethod();
	boolean isOutline = nextPosition.isOutline();
	boolean isOutlineCallerWithInfo =
	nextPosition.isOutlineCaller()
	&& nextPosition.getOutlineCallee() != null
	&& !nextPosition.getOutlinePositions().isEmpty();
	boolean isNoLongerOutlineCaller =
	previousPosition.isOutlineCaller() && !nextPosition.isOutlineCaller();
	if (isNewPosition \|\| isOutline \|\| isOutlineCallerWithInfo \|\| isNoLongerOutlineCaller) {
	events.add(factory.createPositionFrame(nextPosition));
	}
	addDefaultEventWithAdvancePcIfNecessary(lineDelta, pcDelta, events, factory);
	}

	public static void addDefaultEventWithAdvancePcIfNecessary(
	int lineDelta, int pcDelta, List<DexDebugEvent> events, DexItemFactory factory) {
	if (lineDelta < Constants.DBG_LINE_BASE
	\|\| lineDelta - Constants.DBG_LINE_BASE >= Constants.DBG_LINE_RANGE) {
	events.add(factory.createAdvanceLine(lineDelta));
	// TODO(herhut): To be super clever, encode only the part that is above limit.
	lineDelta = 0;
	}
	int specialOpcode = Default.computeSpecialOpcode(lineDelta, pcDelta);
	if (specialOpcode > Constants.DBG_LAST_SPECIAL) {
	events.add(factory.createAdvancePC(pcDelta));
	// TODO(herhut): To be super clever, encode only the part that is above limit.
	specialOpcode = Default.computeSpecialOpcode(lineDelta, 0);
	}
	assert specialOpcode >= Constants.DBG_FIRST_SPECIAL;
	assert specialOpcode <= Constants.DBG_LAST_SPECIAL;
	events.add(factory.createDefault(specialOpcode));
	}

	@SuppressWarnings("ReferenceEquality")
	private static void emitLocalChangeEvents(
	Int2ReferenceMap<DebugLocalInfo> previousLocals,
	Int2ReferenceMap<DebugLocalInfo> nextLocals,
	Int2ReferenceMap<DebugLocalInfo> lastKnownLocals,
	List<DexDebugEvent> events,
	DexItemFactory factory) {
	Int2ReferenceSortedMap<DebugLocalInfo> ending =
	DebugLocalInfo.endingLocals(previousLocals, nextLocals);
	Int2ReferenceSortedMap<DebugLocalInfo> starting =
	DebugLocalInfo.startingLocals(previousLocals, nextLocals);
	assert !ending.isEmpty() \|\| !starting.isEmpty();
	for (Entry<DebugLocalInfo> end : ending.int2ReferenceEntrySet()) {
	int register = end.getIntKey();
	if (!starting.containsKey(register)) {
	previousLocals.remove(register);
	events.add(factory.createEndLocal(register));
	}
	}
	for (Entry<DebugLocalInfo> start : starting.int2ReferenceEntrySet()) {
	int register = start.getIntKey();
	DebugLocalInfo local = start.getValue();
	previousLocals.put(register, local);
	if (lastKnownLocals.get(register) == local) {
	events.add(factory.createRestartLocal(register));
	} else {
	events.add(new StartLocal(register, local));
	lastKnownLocals.put(register, local);
	}
	}
	}
	}