private void addBreakLabel(Edge exitEdge, BlockNode exit, InsnNode breakInsn) {
BlockNode outBlock = BlockUtils.getNextBlock(exitEdge.getTarget());
if (outBlock == null) {
return;
}
List<LoopInfo> exitLoop = mth.getAllLoopsForBlock(outBlock);
if (!exitLoop.isEmpty()) {
return;
}
List<LoopInfo> inLoops = mth.getAllLoopsForBlock(exitEdge.getSource());
if (inLoops.size() < 2) {
return;
}
// search for parent loop
LoopInfo parentLoop = null;
for (LoopInfo loop : inLoops) {
if (loop.getParentLoop() == null) {
parentLoop = loop;
break;
}
}
if (parentLoop == null) {
return;
}
if (parentLoop.getEnd() != exit && !parentLoop.getExitNodes().contains(exit)) {
LoopLabelAttr labelAttr = new LoopLabelAttr(parentLoop);
breakInsn.addAttr(labelAttr);
parentLoop.getStart().addAttr(labelAttr);
}
}
private void processExcHandler(ExceptionHandler handler, Set<BlockNode> exits) {
BlockNode start = handler.getHandlerBlock();
if (start == null) {
return;
}
RegionStack stack = new RegionStack(mth);
BlockNode dom;
if (handler.isFinally()) {
SplitterBlockAttr splitterAttr = start.get(AType.SPLITTER_BLOCK);
if (splitterAttr == null) {
return;
}
dom = splitterAttr.getBlock();
} else {
dom = start;
stack.addExits(exits);
}
BitSet domFrontier = dom.getDomFrontier();
List<BlockNode> handlerExits = BlockUtils.bitSetToBlocks(mth, domFrontier);
boolean inLoop = mth.getLoopForBlock(start) != null;
for (BlockNode exit : handlerExits) {
if ((!inLoop || BlockUtils.isPathExists(start, exit))
&& RegionUtils.isRegionContainsBlock(mth.getRegion(), exit)) {
stack.addExit(exit);
}
}
handler.setHandlerRegion(makeRegion(start, stack));
ExcHandlerAttr excHandlerAttr = start.get(AType.EXC_HANDLER);
if (excHandlerAttr == null) {
LOG.warn("Missing exception handler attribute for start block");
} else {
handler.getHandlerRegion().addAttr(excHandlerAttr);
}
}
protected MethodNode getMethod(ClassNode cls, String method) {
for (MethodNode mth : cls.getMethods()) {
if (mth.getName().equals(method)) {
return mth;
}
}
fail("Method not found " + method + " in class " + cls);
return null;
}
public DebugInfoParser(MethodNode mth, int debugOffset, InsnNode[] insnByOffset) {
this.mth = mth;
this.dex = mth.dex();
this.section = dex.openSection(debugOffset);
int regsCount = mth.getRegsCount();
this.locals = new LocalVar[regsCount];
this.activeRegisters = new InsnArg[regsCount];
this.insnByOffset = insnByOffset;
}
private static void checkCode(ClassNode cls) {
assertTrue(
"Inconsistent cls: " + cls,
!cls.contains(AFlag.INCONSISTENT_CODE) && !cls.contains(AType.JADX_ERROR));
for (MethodNode mthNode : cls.getMethods()) {
assertTrue(
"Inconsistent method: " + mthNode,
!mthNode.contains(AFlag.INCONSISTENT_CODE) && !mthNode.contains(AType.JADX_ERROR));
}
assertThat(cls.getCode().toString(), not(containsString("inconsistent")));
}
private boolean inExceptionHandlerBlocks(BlockNode loopEnd) {
if (mth.getExceptionHandlersCount() == 0) {
return false;
}
for (ExceptionHandler eh : mth.getExceptionHandlers()) {
if (eh.getBlocks().contains(loopEnd)) {
return true;
}
}
return false;
}
private static void renameVariables(MethodNode mth) {
int regsCount = mth.getRegsCount();
SSAVar[] vars = new SSAVar[regsCount];
int[] versions = new int[regsCount];
// init method arguments
for (RegisterArg arg : mth.getArguments(true)) {
int regNum = arg.getRegNum();
vars[regNum] = mth.makeNewSVar(regNum, versions, arg);
}
renameVar(mth, vars, versions, mth.getEnterBlock());
}
/** Select loop exit and construct LoopRegion */
private LoopRegion makeLoopRegion(IRegion curRegion, LoopInfo loop, List<BlockNode> exitBlocks) {
for (BlockNode block : exitBlocks) {
if (block.contains(AType.EXC_HANDLER)
|| block.getInstructions().size() != 1
|| block.getInstructions().get(0).getType() != InsnType.IF) {
continue;
}
List<LoopInfo> loops = block.getAll(AType.LOOP);
if (!loops.isEmpty() && loops.get(0) != loop) {
// skip nested loop condition
continue;
}
LoopRegion loopRegion = new LoopRegion(curRegion, loop, block, block == loop.getEnd());
boolean found;
if (block == loop.getStart()
|| block == loop.getEnd()
|| BlockUtils.isEmptySimplePath(loop.getStart(), block)) {
found = true;
} else if (block.getPredecessors().contains(loop.getStart())) {
loopRegion.setPreCondition(loop.getStart());
// if we can't merge pre-condition this is not correct header
found = loopRegion.checkPreCondition();
} else {
found = false;
}
if (found) {
List<LoopInfo> list = mth.getAllLoopsForBlock(block);
if (list.size() >= 2) {
// bad condition if successors going out of all loops
boolean allOuter = true;
for (BlockNode outerBlock : block.getCleanSuccessors()) {
List<LoopInfo> outLoopList = mth.getAllLoopsForBlock(outerBlock);
outLoopList.remove(loop);
if (!outLoopList.isEmpty()) {
// goes to outer loop
allOuter = false;
break;
}
}
if (allOuter) {
found = false;
}
}
}
if (found) {
return loopRegion;
}
}
// no exit found => endless loop
return null;
}
private static void placePhi(MethodNode mth, int regNum, LiveVarAnalysis la) {
List<BlockNode> blocks = mth.getBasicBlocks();
int blocksCount = blocks.size();
BitSet hasPhi = new BitSet(blocksCount);
BitSet processed = new BitSet(blocksCount);
Deque<BlockNode> workList = new LinkedList<BlockNode>();
BitSet assignBlocks = la.getAssignBlocks(regNum);
for (int id = assignBlocks.nextSetBit(0); id >= 0; id = assignBlocks.nextSetBit(id + 1)) {
processed.set(id);
workList.add(blocks.get(id));
}
while (!workList.isEmpty()) {
BlockNode block = workList.pop();
BitSet domFrontier = block.getDomFrontier();
for (int id = domFrontier.nextSetBit(0); id >= 0; id = domFrontier.nextSetBit(id + 1)) {
if (!hasPhi.get(id) && la.isLive(id, regNum)) {
BlockNode df = blocks.get(id);
addPhi(df, regNum);
hasPhi.set(id);
if (!processed.get(id)) {
processed.set(id);
workList.add(df);
}
}
}
}
}
@Override
public void visit(MethodNode mth) throws JadxException {
if (mth.isNoCode()) {
return;
}
process(mth);
}
private static boolean removePhiList(MethodNode mth, List<PhiInsn> insnToRemove) {
if (insnToRemove.isEmpty()) {
return false;
}
for (BlockNode block : mth.getBasicBlocks()) {
PhiListAttr phiList = block.get(AType.PHI_LIST);
if (phiList == null) {
continue;
}
List<PhiInsn> list = phiList.getList();
for (PhiInsn phiInsn : insnToRemove) {
if (list.remove(phiInsn)) {
for (InsnArg arg : phiInsn.getArguments()) {
SSAVar sVar = ((RegisterArg) arg).getSVar();
if (sVar != null) {
sVar.setUsedInPhi(null);
}
}
InstructionRemover.remove(mth, block, phiInsn);
}
}
if (list.isEmpty()) {
block.remove(AType.PHI_LIST);
}
}
insnToRemove.clear();
return true;
}
private static void renameVar(MethodNode mth, SSAVar[] vars, int[] vers, BlockNode block) {
SSAVar[] inputVars = Arrays.copyOf(vars, vars.length);
for (InsnNode insn : block.getInstructions()) {
if (insn.getType() != InsnType.PHI) {
for (InsnArg arg : insn.getArguments()) {
if (!arg.isRegister()) {
continue;
}
RegisterArg reg = (RegisterArg) arg;
int regNum = reg.getRegNum();
SSAVar var = vars[regNum];
if (var == null) {
throw new JadxRuntimeException(
"Not initialized variable reg: "
+ regNum
+ ", insn: "
+ insn
+ ", block:"
+ block
+ ", method: "
+ mth);
}
var.use(reg);
}
}
RegisterArg result = insn.getResult();
if (result != null) {
int regNum = result.getRegNum();
vars[regNum] = mth.makeNewSVar(regNum, vers, result);
}
}
for (BlockNode s : block.getSuccessors()) {
PhiListAttr phiList = s.get(AType.PHI_LIST);
if (phiList == null) {
continue;
}
int j = s.getPredecessors().indexOf(block);
if (j == -1) {
throw new JadxRuntimeException("Can't find predecessor for " + block + " " + s);
}
for (PhiInsn phiInsn : phiList.getList()) {
if (j >= phiInsn.getArgsCount()) {
continue;
}
int regNum = phiInsn.getResult().getRegNum();
SSAVar var = vars[regNum];
if (var == null) {
continue;
}
var.use(phiInsn.getArg(j));
var.setUsedInPhi(phiInsn);
}
}
for (BlockNode domOn : block.getDominatesOn()) {
renameVar(mth, vars, vers, domOn);
}
System.arraycopy(inputVars, 0, vars, 0, vars.length);
}
private static void process(MethodNode mth) {
LiveVarAnalysis la = new LiveVarAnalysis(mth);
la.runAnalysis();
int regsCount = mth.getRegsCount();
for (int i = 0; i < regsCount; i++) {
placePhi(mth, i, la);
}
renameVariables(mth);
fixLastTryCatchAssign(mth);
if (removeUselessPhi(mth)) {
renameVariables(mth);
}
}
private static boolean removeUselessPhi(MethodNode mth) {
List<PhiInsn> insnToRemove = new ArrayList<PhiInsn>();
for (SSAVar var : mth.getSVars()) {
// phi result not used
if (var.getUseCount() == 0) {
InsnNode assignInsn = var.getAssign().getParentInsn();
if (assignInsn != null && assignInsn.getType() == InsnType.PHI) {
insnToRemove.add((PhiInsn) assignInsn);
}
}
}
for (BlockNode block : mth.getBasicBlocks()) {
PhiListAttr phiList = block.get(AType.PHI_LIST);
if (phiList == null) {
continue;
}
for (PhiInsn phi : phiList.getList()) {
removePhiWithSameArgs(phi, insnToRemove);
}
}
return removePhiList(mth, insnToRemove);
}
private static void fixLastTryCatchAssign(MethodNode mth) {
for (BlockNode block : mth.getBasicBlocks()) {
PhiListAttr phiList = block.get(AType.PHI_LIST);
if (phiList == null || !block.contains(AType.EXC_HANDLER)) {
continue;
}
for (PhiInsn phi : phiList.getList()) {
for (int i = 0; i < phi.getArgsCount(); i++) {
RegisterArg arg = phi.getArg(i);
InsnNode parentInsn = arg.getAssignInsn();
if (parentInsn != null
&& parentInsn.getResult() != null
&& parentInsn.contains(AFlag.TRY_LEAVE)) {
phi.removeArg(arg);
}
}
}
}
}
private boolean canInsertBreak(BlockNode exit) {
if (exit.contains(AFlag.RETURN) || BlockUtils.checkLastInsnType(exit, InsnType.BREAK)) {
return false;
}
List<BlockNode> simplePath = BlockUtils.buildSimplePath(exit);
if (!simplePath.isEmpty()) {
BlockNode lastBlock = simplePath.get(simplePath.size() - 1);
if (lastBlock.contains(AFlag.RETURN) || lastBlock.getSuccessors().isEmpty()) {
return false;
}
}
// check if there no outer switch (TODO: very expensive check)
Set<BlockNode> paths = BlockUtils.getAllPathsBlocks(mth.getEnterBlock(), exit);
for (BlockNode block : paths) {
if (BlockUtils.checkLastInsnType(block, InsnType.SWITCH)) {
return false;
}
}
return true;
}
public void processTryCatchBlocks(MethodNode mth) {
Set<TryCatchBlock> tcs = new HashSet<TryCatchBlock>();
for (ExceptionHandler handler : mth.getExceptionHandlers()) {
tcs.add(handler.getTryBlock());
}
for (TryCatchBlock tc : tcs) {
List<BlockNode> blocks = new ArrayList<BlockNode>(tc.getHandlersCount());
Set<BlockNode> splitters = new HashSet<BlockNode>();
for (ExceptionHandler handler : tc.getHandlers()) {
BlockNode handlerBlock = handler.getHandlerBlock();
if (handlerBlock != null) {
blocks.add(handlerBlock);
splitters.addAll(handlerBlock.getPredecessors());
} else {
LOG.debug(ErrorsCounter.formatErrorMsg(mth, "No exception handler block: " + handler));
}
}
Set<BlockNode> exits = new HashSet<BlockNode>();
for (BlockNode splitter : splitters) {
for (BlockNode handler : blocks) {
List<BlockNode> s = splitter.getSuccessors();
if (s.isEmpty()) {
LOG.debug(ErrorsCounter.formatErrorMsg(mth, "No successors for splitter: " + splitter));
continue;
}
BlockNode ss = s.get(0);
BlockNode cross = BlockUtils.getPathCross(mth, ss, handler);
if (cross != null && cross != ss && cross != handler) {
exits.add(cross);
}
}
}
for (ExceptionHandler handler : tc.getHandlers()) {
processExcHandler(handler, exits);
}
}
}
public RegionMaker(MethodNode mth) {
this.mth = mth;
if (Consts.DEBUG) {
this.processedBlocks = new BitSet(mth.getBasicBlocks().size());
}
}
private BlockNode processSwitch(
IRegion currentRegion, BlockNode block, SwitchNode insn, RegionStack stack) {
SwitchRegion sw = new SwitchRegion(currentRegion, block);
currentRegion.getSubBlocks().add(sw);
int len = insn.getTargets().length;
// sort by target
Map<Integer, List<Object>> casesMap = new LinkedHashMap<Integer, List<Object>>(len);
for (int i = 0; i < len; i++) {
Object key = insn.getKeys()[i];
int targ = insn.getTargets()[i];
List<Object> keys = casesMap.get(targ);
if (keys == null) {
keys = new ArrayList<Object>(2);
casesMap.put(targ, keys);
}
keys.add(key);
}
Map<BlockNode, List<Object>> blocksMap = new LinkedHashMap<BlockNode, List<Object>>(len);
for (Map.Entry<Integer, List<Object>> entry : casesMap.entrySet()) {
BlockNode c = getBlockByOffset(entry.getKey(), block.getSuccessors());
assert c != null;
blocksMap.put(c, entry.getValue());
}
BlockNode defCase = getBlockByOffset(insn.getDefaultCaseOffset(), block.getSuccessors());
if (defCase != null) {
blocksMap.remove(defCase);
}
LoopInfo loop = mth.getLoopForBlock(block);
Map<BlockNode, BlockNode> fallThroughCases = new LinkedHashMap<BlockNode, BlockNode>();
List<BlockNode> basicBlocks = mth.getBasicBlocks();
BitSet outs = new BitSet(basicBlocks.size());
outs.or(block.getDomFrontier());
for (BlockNode s : block.getCleanSuccessors()) {
BitSet df = s.getDomFrontier();
// fall through case block
if (df.cardinality() > 1) {
if (df.cardinality() > 2) {
LOG.debug("Unexpected case pattern, block: {}, mth: {}", s, mth);
} else {
BlockNode first = basicBlocks.get(df.nextSetBit(0));
BlockNode second = basicBlocks.get(df.nextSetBit(first.getId() + 1));
if (second.getDomFrontier().get(first.getId())) {
fallThroughCases.put(s, second);
df = new BitSet(df.size());
df.set(first.getId());
} else if (first.getDomFrontier().get(second.getId())) {
fallThroughCases.put(s, first);
df = new BitSet(df.size());
df.set(second.getId());
}
}
}
outs.or(df);
}
outs.clear(block.getId());
if (loop != null) {
outs.clear(loop.getStart().getId());
}
stack.push(sw);
stack.addExits(BlockUtils.bitSetToBlocks(mth, outs));
// check cases order if fall through case exists
if (!fallThroughCases.isEmpty()) {
if (isBadCasesOrder(blocksMap, fallThroughCases)) {
LOG.debug("Fixing incorrect switch cases order, method: {}", mth);
blocksMap = reOrderSwitchCases(blocksMap, fallThroughCases);
if (isBadCasesOrder(blocksMap, fallThroughCases)) {
LOG.error("Can't fix incorrect switch cases order, method: {}", mth);
mth.add(AFlag.INCONSISTENT_CODE);
}
}
}
// filter 'out' block
if (outs.cardinality() > 1) {
// remove exception handlers
BlockUtils.cleanBitSet(mth, outs);
}
if (outs.cardinality() > 1) {
// filter loop start and successors of other blocks
for (int i = outs.nextSetBit(0); i >= 0; i = outs.nextSetBit(i + 1)) {
BlockNode b = basicBlocks.get(i);
outs.andNot(b.getDomFrontier());
if (b.contains(AFlag.LOOP_START)) {
outs.clear(b.getId());
} else {
for (BlockNode s : b.getCleanSuccessors()) {
outs.clear(s.getId());
}
}
}
}
if (loop != null && outs.cardinality() > 1) {
outs.clear(loop.getEnd().getId());
}
if (outs.cardinality() == 0) {
// one or several case blocks are empty,
// run expensive algorithm for find 'out' block
for (BlockNode maybeOut : block.getSuccessors()) {
boolean allReached = true;
for (BlockNode s : block.getSuccessors()) {
if (!isPathExists(s, maybeOut)) {
allReached = false;
break;
}
}
if (allReached) {
outs.set(maybeOut.getId());
break;
}
}
}
BlockNode out = null;
if (outs.cardinality() == 1) {
out = basicBlocks.get(outs.nextSetBit(0));
stack.addExit(out);
} else if (loop == null && outs.cardinality() > 1) {
LOG.warn("Can't detect out node for switch block: {} in {}", block, mth);
}
if (loop != null) {
// check if 'continue' must be inserted
BlockNode end = loop.getEnd();
if (out != end && out != null) {
insertContinueInSwitch(block, out, end);
}
}
if (!stack.containsExit(defCase)) {
sw.setDefaultCase(makeRegion(defCase, stack));
}
for (Entry<BlockNode, List<Object>> entry : blocksMap.entrySet()) {
BlockNode caseBlock = entry.getKey();
if (stack.containsExit(caseBlock)) {
// empty case block
sw.addCase(entry.getValue(), new Region(stack.peekRegion()));
} else {
BlockNode next = fallThroughCases.get(caseBlock);
stack.addExit(next);
Region caseRegion = makeRegion(caseBlock, stack);
stack.removeExit(next);
if (next != null) {
next.add(AFlag.FALL_THROUGH);
caseRegion.add(AFlag.FALL_THROUGH);
}
sw.addCase(entry.getValue(), caseRegion);
// 'break' instruction will be inserted in RegionMakerVisitor.PostRegionVisitor
}
}
stack.pop();
return out;
}
public void process() throws DecodeException {
int addr = 0;
int line = section.readUleb128();
int paramsCount = section.readUleb128();
List<RegisterArg> mthArgs = mth.getArguments(false);
assert paramsCount == mthArgs.size();
for (int i = 0; i < paramsCount; i++) {
int id = section.readUleb128() - 1;
if (id != DexNode.NO_INDEX) {
String name = dex.getString(id);
mthArgs.get(i).setName(name);
}
}
for (RegisterArg arg : mthArgs) {
int rn = arg.getRegNum();
locals[rn] = new LocalVar(arg);
activeRegisters[rn] = arg;
}
// process '0' instruction
addrChange(-1, 1, line);
setLine(addr, line);
int c = section.readByte() & 0xFF;
while (c != DBG_END_SEQUENCE) {
switch (c) {
case DBG_ADVANCE_PC:
{
int addrInc = section.readUleb128();
addr = addrChange(addr, addrInc, line);
setLine(addr, line);
break;
}
case DBG_ADVANCE_LINE:
{
line += section.readSleb128();
break;
}
case DBG_START_LOCAL:
{
int regNum = section.readUleb128();
int nameId = section.readUleb128() - 1;
int type = section.readUleb128() - 1;
LocalVar var = new LocalVar(dex, regNum, nameId, type, DexNode.NO_INDEX);
startVar(var, addr, line);
break;
}
case DBG_START_LOCAL_EXTENDED:
{
int regNum = section.readUleb128();
int nameId = section.readUleb128() - 1;
int type = section.readUleb128() - 1;
int sign = section.readUleb128() - 1;
LocalVar var = new LocalVar(dex, regNum, nameId, type, sign);
startVar(var, addr, line);
break;
}
case DBG_RESTART_LOCAL:
{
int regNum = section.readUleb128();
LocalVar var = locals[regNum];
if (var != null) {
var.end(addr, line);
setVar(var);
var.start(addr, line);
}
break;
}
case DBG_END_LOCAL:
{
int regNum = section.readUleb128();
LocalVar var = locals[regNum];
if (var != null) {
var.end(addr, line);
setVar(var);
}
break;
}
case DBG_SET_PROLOGUE_END:
case DBG_SET_EPILOGUE_BEGIN:
// do nothing
break;
case DBG_SET_FILE:
{
int idx = section.readUleb128() - 1;
if (idx != DexNode.NO_INDEX) {
String sourceFile = dex.getString(idx);
mth.addAttr(new SourceFileAttr(sourceFile));
}
break;
}
default:
{
if (c >= DBG_FIRST_SPECIAL) {
int adjustedOpcode = c - DBG_FIRST_SPECIAL;
int addrInc = adjustedOpcode / DBG_LINE_RANGE;
addr = addrChange(addr, addrInc, line);
line += DBG_LINE_BASE + (adjustedOpcode % DBG_LINE_RANGE);
setLine(addr, line);
} else {
throw new DecodeException("Unknown debug insn code: " + c);
}
break;
}
}
c = section.readByte() & 0xFF;
}
for (LocalVar var : locals) {
if (var != null && !var.isEnd()) {
var.end(addr, line);
setVar(var);
}
}
setSourceLines(addr, insnByOffset.length, line);
}