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 com.android.tools.r8.dex.Constants;
 import com.android.tools.r8.graph.DexDebugEvent.StartLocal;
 import com.android.tools.r8.ir.code.Argument;
 import com.android.tools.r8.ir.code.DebugLocalsChange;
 import com.android.tools.r8.ir.code.DebugPosition;
 import com.android.tools.r8.ir.code.Instruction;
 import com.android.tools.r8.ir.code.MoveException;
 import it.unimi.dsi.fastutil.ints.Int2ReferenceAVLTreeMap;
 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 {

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

   private final DexEncodedMethod method;
   private final DexItemFactory factory;

   // 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 int emittedLine = NO_LINE_INFO;
   private DexString emittedFile = null;
   private Int2ReferenceMap<DebugLocalInfo> emittedLocals;

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

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

   public DexDebugEventBuilder(DexEncodedMethod method, DexItemFactory factory) {
     this.method = method;
     this.factory = factory;
   }

   // Public method for the DebugStripper.
   public void setPosition(int pc, int line) {
     emitDebugPosition(pc, line, null);
   }

   /** Add events at pc for instruction. */
   public void add(int pc, Instruction instruction) {
     // Initialize locals state on block entry.
     if (instruction.getBlock().entry() == instruction) {
       updateBlockEntry(instruction);
     }
     assert pendingLocals != null;

     if (instruction.isDebugPosition()) {
       emitDebugPosition(pc, instruction.asDebugPosition());
     } else if (instruction.isMoveException()) {
       MoveException move = instruction.asMoveException();
       if (move.getPosition() != null) {
         emitDebugPosition(pc, move.getPosition());
       }
     } else if (instruction.isArgument()) {
       startArgument(instruction.asArgument());
     } else if (instruction.isDebugLocalsChange()) {
       updateLocals(instruction.asDebugLocalsChange());
     } else if (instruction.getBlock().exit() == instruction) {
       // If this is the end of the block clear out the pending state.
       pendingLocals = null;
       pendingLocalChanges = false;
     } else {
       // For non-exit / pc-advancing instructions emit any pending changes.
       emitLocalChanges(pc);
     }
   }

   /** 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.method.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;
       }
     }
     return new DexDebugInfo(startLine, params, events.toArray(new DexDebugEvent[events.size()]));
   }

   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());
       }
     }
     lastKnownLocals = new Int2ReferenceOpenHashMap<>(emittedLocals);
   }

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

   private void updateLocals(DebugLocalsChange change) {
     pendingLocalChanges = true;
     for (Entry<DebugLocalInfo> end : change.getEnding().int2ReferenceEntrySet()) {
       assert pendingLocals.get(end.getIntKey()) == end.getValue();
       pendingLocals.remove(end.getIntKey());
     }
     for (Entry<DebugLocalInfo> start : change.getStarting().int2ReferenceEntrySet()) {
       assert !pendingLocals.containsKey(start.getIntKey());
       pendingLocals.put(start.getIntKey(), start.getValue());
     }
   }

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

   private void emitDebugPosition(int pc, DebugPosition position) {
     emitDebugPosition(pc, position.line, position.file);
   }

   private void emitDebugPosition(int pc, int line, DexString file) {
     // The position requires a pc change event and possible events for line, file and local changes.
     // Verify that we do not ever produce two subsequent positions at the same pc.
     assert emittedPc != pc;
     if (startLine == NO_LINE_INFO) {
       assert emittedLine == NO_LINE_INFO;
       startLine = line;
       emittedLine = line;
     }
     emitAdvancementEvents(emittedPc, emittedLine, emittedFile, pc, line, file, events, factory);
     emittedPc = pc;
     emittedLine = line;
     emittedFile = file;
     if (localsChanged()) {
       emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
       assert localsEqual(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()) {
       emitAdvancementEvents(
           emittedPc, emittedLine, emittedFile, pc, emittedLine, emittedFile, events, factory);
       emittedPc = pc;
       emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
       pendingLocalChanges = false;
       assert localsEqual(emittedLocals, pendingLocals);
     }
   }

   private static void emitAdvancementEvents(
       int previousPc,
       int previousLine,
       DexString previousFile,
       int nextPc,
       int nextLine,
       DexString nextFile,
       List<DexDebugEvent> events,
       DexItemFactory factory) {
     int pcDelta = previousPc == NO_PC_INFO ? nextPc : nextPc - previousPc;
     int lineDelta = nextLine == NO_LINE_INFO ? 0 : nextLine - previousLine;
     assert pcDelta >= 0;
     if (nextFile != previousFile) {
       events.add(factory.createSetFile(nextFile));
     }
     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;
     }
     if (pcDelta >= Constants.DBG_ADDRESS_RANGE) {
       events.add(factory.createAdvancePC(pcDelta));
       pcDelta = 0;
     }
     // TODO(herhut): Maybe only write this one if needed (would differ from DEX).
     int specialOpcode =
         0x0a + (lineDelta - Constants.DBG_LINE_BASE) + Constants.DBG_LINE_RANGE * pcDelta;
     assert specialOpcode >= 0x0a;
     assert specialOpcode <= 0xff;
     events.add(factory.createDefault(specialOpcode));
   }

   public static void emitLocalChangeEvents(
       Int2ReferenceMap<DebugLocalInfo> previousLocals,
       Int2ReferenceMap<DebugLocalInfo> nextLocals,
       Int2ReferenceMap<DebugLocalInfo> lastKnownLocals,
       List<DexDebugEvent> events,
       DexItemFactory factory) {
     Int2ReferenceSortedMap<DebugLocalInfo> ending = new Int2ReferenceAVLTreeMap<>();
     Int2ReferenceSortedMap<DebugLocalInfo> starting = new Int2ReferenceAVLTreeMap<>();
     for (Entry<DebugLocalInfo> entry : previousLocals.int2ReferenceEntrySet()) {
       int register = entry.getIntKey();
       DebugLocalInfo local = entry.getValue();
       if (nextLocals.get(register) != local) {
         ending.put(register, local);
       }
     }
     for (Entry<DebugLocalInfo> entry : nextLocals.int2ReferenceEntrySet()) {
       int register = entry.getIntKey();
       DebugLocalInfo local = entry.getValue();
       if (previousLocals.get(register) != local) {
         starting.put(register, local);
       }
     }
     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);
       }
     }
   }

   private static boolean localsEqual(
       Int2ReferenceMap<DebugLocalInfo> locals1, Int2ReferenceMap<DebugLocalInfo> locals2) {
     if (locals1 == locals2) {
       return true;
     }
     if (locals1.size() != locals2.size()) {
       return false;
     }
     for (Int2ReferenceMap.Entry<DebugLocalInfo> entry : locals1.int2ReferenceEntrySet()) {
       if (locals2.get(entry.getIntKey()) != entry.getValue()) {
         return false;
       }
     }
     return true;
   }
 }
	// 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 com.android.tools.r8.dex.Constants;
	import com.android.tools.r8.graph.DexDebugEvent.StartLocal;
	import com.android.tools.r8.ir.code.Argument;
	import com.android.tools.r8.ir.code.DebugLocalsChange;
	import com.android.tools.r8.ir.code.DebugPosition;
	import com.android.tools.r8.ir.code.Instruction;
	import com.android.tools.r8.ir.code.MoveException;
	import it.unimi.dsi.fastutil.ints.Int2ReferenceAVLTreeMap;
	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 {

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

	private final DexEncodedMethod method;
	private final DexItemFactory factory;

	// 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 int emittedLine = NO_LINE_INFO;
	private DexString emittedFile = null;
	private Int2ReferenceMap<DebugLocalInfo> emittedLocals;

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

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

	public DexDebugEventBuilder(DexEncodedMethod method, DexItemFactory factory) {
	this.method = method;
	this.factory = factory;
	}

	// Public method for the DebugStripper.
	public void setPosition(int pc, int line) {
	emitDebugPosition(pc, line, null);
	}

	/** Add events at pc for instruction. */
	public void add(int pc, Instruction instruction) {
	// Initialize locals state on block entry.
	if (instruction.getBlock().entry() == instruction) {
	updateBlockEntry(instruction);
	}
	assert pendingLocals != null;

	if (instruction.isDebugPosition()) {
	emitDebugPosition(pc, instruction.asDebugPosition());
	} else if (instruction.isMoveException()) {
	MoveException move = instruction.asMoveException();
	if (move.getPosition() != null) {
	emitDebugPosition(pc, move.getPosition());
	}
	} else if (instruction.isArgument()) {
	startArgument(instruction.asArgument());
	} else if (instruction.isDebugLocalsChange()) {
	updateLocals(instruction.asDebugLocalsChange());
	} else if (instruction.getBlock().exit() == instruction) {
	// If this is the end of the block clear out the pending state.
	pendingLocals = null;
	pendingLocalChanges = false;
	} else {
	// For non-exit / pc-advancing instructions emit any pending changes.
	emitLocalChanges(pc);
	}
	}

	/** 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.method.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;
	}
	}
	return new DexDebugInfo(startLine, params, events.toArray(new DexDebugEvent[events.size()]));
	}

	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());
	}
	}
	lastKnownLocals = new Int2ReferenceOpenHashMap<>(emittedLocals);
	}

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

	private void updateLocals(DebugLocalsChange change) {
	pendingLocalChanges = true;
	for (Entry<DebugLocalInfo> end : change.getEnding().int2ReferenceEntrySet()) {
	assert pendingLocals.get(end.getIntKey()) == end.getValue();
	pendingLocals.remove(end.getIntKey());
	}
	for (Entry<DebugLocalInfo> start : change.getStarting().int2ReferenceEntrySet()) {
	assert !pendingLocals.containsKey(start.getIntKey());
	pendingLocals.put(start.getIntKey(), start.getValue());
	}
	}

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

	private void emitDebugPosition(int pc, DebugPosition position) {
	emitDebugPosition(pc, position.line, position.file);
	}

	private void emitDebugPosition(int pc, int line, DexString file) {
	// The position requires a pc change event and possible events for line, file and local changes.
	// Verify that we do not ever produce two subsequent positions at the same pc.
	assert emittedPc != pc;
	if (startLine == NO_LINE_INFO) {
	assert emittedLine == NO_LINE_INFO;
	startLine = line;
	emittedLine = line;
	}
	emitAdvancementEvents(emittedPc, emittedLine, emittedFile, pc, line, file, events, factory);
	emittedPc = pc;
	emittedLine = line;
	emittedFile = file;
	if (localsChanged()) {
	emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
	assert localsEqual(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()) {
	emitAdvancementEvents(
	emittedPc, emittedLine, emittedFile, pc, emittedLine, emittedFile, events, factory);
	emittedPc = pc;
	emitLocalChangeEvents(emittedLocals, pendingLocals, lastKnownLocals, events, factory);
	pendingLocalChanges = false;
	assert localsEqual(emittedLocals, pendingLocals);
	}
	}

	private static void emitAdvancementEvents(
	int previousPc,
	int previousLine,
	DexString previousFile,
	int nextPc,
	int nextLine,
	DexString nextFile,
	List<DexDebugEvent> events,
	DexItemFactory factory) {
	int pcDelta = previousPc == NO_PC_INFO ? nextPc : nextPc - previousPc;
	int lineDelta = nextLine == NO_LINE_INFO ? 0 : nextLine - previousLine;
	assert pcDelta >= 0;
	if (nextFile != previousFile) {
	events.add(factory.createSetFile(nextFile));
	}
	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;
	}
	if (pcDelta >= Constants.DBG_ADDRESS_RANGE) {
	events.add(factory.createAdvancePC(pcDelta));
	pcDelta = 0;
	}
	// TODO(herhut): Maybe only write this one if needed (would differ from DEX).
	int specialOpcode =
	0x0a + (lineDelta - Constants.DBG_LINE_BASE) + Constants.DBG_LINE_RANGE * pcDelta;
	assert specialOpcode >= 0x0a;
	assert specialOpcode <= 0xff;
	events.add(factory.createDefault(specialOpcode));
	}

	public static void emitLocalChangeEvents(
	Int2ReferenceMap<DebugLocalInfo> previousLocals,
	Int2ReferenceMap<DebugLocalInfo> nextLocals,
	Int2ReferenceMap<DebugLocalInfo> lastKnownLocals,
	List<DexDebugEvent> events,
	DexItemFactory factory) {
	Int2ReferenceSortedMap<DebugLocalInfo> ending = new Int2ReferenceAVLTreeMap<>();
	Int2ReferenceSortedMap<DebugLocalInfo> starting = new Int2ReferenceAVLTreeMap<>();
	for (Entry<DebugLocalInfo> entry : previousLocals.int2ReferenceEntrySet()) {
	int register = entry.getIntKey();
	DebugLocalInfo local = entry.getValue();
	if (nextLocals.get(register) != local) {
	ending.put(register, local);
	}
	}
	for (Entry<DebugLocalInfo> entry : nextLocals.int2ReferenceEntrySet()) {
	int register = entry.getIntKey();
	DebugLocalInfo local = entry.getValue();
	if (previousLocals.get(register) != local) {
	starting.put(register, local);
	}
	}
	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);
	}
	}
	}

	private static boolean localsEqual(
	Int2ReferenceMap<DebugLocalInfo> locals1, Int2ReferenceMap<DebugLocalInfo> locals2) {
	if (locals1 == locals2) {
	return true;
	}
	if (locals1.size() != locals2.size()) {
	return false;
	}
	for (Int2ReferenceMap.Entry<DebugLocalInfo> entry : locals1.int2ReferenceEntrySet()) {
	if (locals2.get(entry.getIntKey()) != entry.getValue()) {
	return false;
	}
	}
	return true;
	}
	}