core: fix some 'try/catch/finally' cases

jadx-core/src/main/java/jadx/core/codegen/ClassGen.java

@@ -264,8 +264,10 @@ public class ClassGen {
 			try {
 				addMethod(code, mth);
 			} catch (Exception e) {
-				String msg = ErrorsCounter.methodError(mth, "Method generation error", e);
-				code.startLine("/* " + msg + CodeWriter.NL + Utils.getStackTrace(e) + " */");
+				code.newLine().add("/*");
+				code.newLine().add(ErrorsCounter.methodError(mth, "Method generation error", e));
+				code.newLine().add(Utils.getStackTrace(e));
+				code.newLine().add("*/");
 			}
 		}
 	}

jadx-core/src/main/java/jadx/core/codegen/InsnGen.java

@@ -510,7 +510,18 @@ public class InsnGen {
 			case NEW_INSTANCE:
 				// only fallback - make new instance in constructor invoke
 				fallbackOnlyInsn(insn);
-				code.add("new " + insn.getResult().getType());
+				code.add("new ").add(insn.getResult().getType().toString());
+				break;
+
+			case PHI:
+			case MERGE:
+				fallbackOnlyInsn(insn);
+				code.add(insn.getType().toString()).add("(");
+				for (InsnArg insnArg : insn.getArguments()) {
+					addArg(code, insnArg);
+					code.add(' ');
+				}
+				code.add(")");
 				break;
 
 			default:

jadx-core/src/main/java/jadx/core/codegen/MethodGen.java

@@ -167,7 +167,7 @@ public class MethodGen {
 				if (cause != null) {
 					code.newLine();
 					code.add("/*");
-					code.startLine("Error: ").add(Utils.getStackTrace(cause));
+					code.newLine().add("Error: ").add(Utils.getStackTrace(cause));
 					code.add("*/");
 				}
 			}

jadx-core/src/main/java/jadx/core/dex/instructions/InsnType.java

@@ -65,6 +65,9 @@ public enum InsnType {
 	ONE_ARG,
 	PHI,
 
+	// merge all arguments in one
+	MERGE,
+
 	// TODO: now multidimensional arrays created using Array.newInstance function
 	NEW_MULTIDIM_ARRAY
 }

jadx-core/src/main/java/jadx/core/dex/instructions/args/RegisterArg.java

@@ -77,8 +77,14 @@ public class RegisterArg extends InsnArg implements Named {
 	}
 
 	public RegisterArg duplicate() {
-		RegisterArg dup = new RegisterArg(getRegNum(), getType());
-		dup.setSVar(sVar);
+		return duplicate(getRegNum(), sVar);
+	}
+
+	public RegisterArg duplicate(int regNum, SSAVar sVar) {
+		RegisterArg dup = new RegisterArg(regNum, getType());
+		if (sVar != null) {
+			dup.setSVar(sVar);
+		}
 		dup.copyAttributesFrom(this);
 		return dup;
 	}

jadx-core/src/main/java/jadx/core/dex/nodes/MethodNode.java

@@ -554,9 +554,8 @@ public class MethodNode extends LineAttrNode implements ILoadable {
 		return debugInfoOffset;
 	}
 
-	public SSAVar makeNewSVar(int regNum, int[] versions, @NotNull RegisterArg arg) {
-		SSAVar var = new SSAVar(regNum, versions[regNum], arg);
-		versions[regNum]++;
+	public SSAVar makeNewSVar(int regNum, int version, @NotNull RegisterArg assignArg) {
+		SSAVar var = new SSAVar(regNum, version, assignArg);
 		if (sVars.isEmpty()) {
 			sVars = new ArrayList<SSAVar>();
 		}
@@ -564,6 +563,17 @@ public class MethodNode extends LineAttrNode implements ILoadable {
 		return var;
 	}
 
+	public int getNextSVarVersion(int regNum) {
+		int v = -1;
+		for (SSAVar sVar : sVars) {
+			if (sVar.getRegNum() == regNum) {
+				v = Math.max(v, sVar.getVersion());
+			}
+		}
+		v++;
+		return v;
+	}
+
 	public void removeSVar(SSAVar var) {
 		sVars.remove(var);
 	}

jadx-core/src/main/java/jadx/core/dex/visitors/ConstInlineVisitor.java

@@ -103,7 +103,9 @@ public class ConstInlineVisitor extends AbstractVisitor {
 		int replaceCount = 0;
 		for (RegisterArg arg : use) {
 			InsnNode useInsn = arg.getParentInsn();
-			if (useInsn == null || useInsn.getType() == InsnType.PHI) {
+			if (useInsn == null
+					|| useInsn.getType() == InsnType.PHI
+					|| useInsn.getType() == InsnType.MERGE) {
 				continue;
 			}
 			LiteralArg litArg;

jadx-core/src/main/java/jadx/core/dex/visitors/blocksmaker/BlockFinallyExtract.java

@@ -162,7 +162,7 @@ public class BlockFinallyExtract extends AbstractVisitor {
 			return false;
 		}
 
-		/* 'finally' extract confirmed, run remove steps */
+		// 'finally' extract confirmed, run remove steps
 
 		LiveVarAnalysis laBefore = null;
 		boolean runReMap = isReMapNeeded(removes);
@@ -191,7 +191,7 @@ public class BlockFinallyExtract extends AbstractVisitor {
 
 				RegisterArg resArg = me.getResult();
 				BlockNode succ = handlerBlock.getCleanSuccessors().get(0);
-				if (laAfter.isLive(succ.getId(), resArg.getRegNum())) {
+				if (laAfter.isLive(succ, resArg.getRegNum())) {
 					// kill variable
 					InsnNode kill = new InsnNode(InsnType.NOP, 0);
 					kill.setResult(resArg);
@@ -224,34 +224,59 @@ public class BlockFinallyExtract extends AbstractVisitor {
 		BitSet processed = new BitSet(mth.getRegsCount());
 		for (BlocksRemoveInfo removeInfo : removes) {
 			processed.clear();
-			BlockNode insertBlock = removeInfo.getStart().getSecond();
+			BlocksPair start = removeInfo.getStart();
+			BlockNode insertBlockBefore = start.getFirst();
+			BlockNode insertBlock = start.getSecond();
 			if (removeInfo.getRegMap().isEmpty() || insertBlock == null) {
 				continue;
 			}
 			for (Map.Entry<RegisterArg, RegisterArg> entry : removeInfo.getRegMap().entrySet()) {
-				RegisterArg from = entry.getKey();
-				int regNum = from.getRegNum();
-				if (!processed.get(regNum)) {
-					if (laBefore.isLive(insertBlock.getId(), regNum)) {
+				RegisterArg fromReg = entry.getKey();
+				RegisterArg toReg = entry.getValue();
+				int fromRegNum = fromReg.getRegNum();
+				int toRegNum = toReg.getRegNum();
+				if (!processed.get(fromRegNum)) {
+					boolean liveFromBefore = laBefore.isLive(insertBlockBefore, fromRegNum);
+					boolean liveFromAfter = laAfter.isLive(insertBlock, fromRegNum);
+					// boolean liveToBefore = laBefore.isLive(insertBlock, toRegNum);
+					boolean liveToAfter = laAfter.isLive(insertBlock, toRegNum);
+					if (liveToAfter && liveFromBefore) {
+						// merge 'to' and 'from' registers
+						InsnNode merge = new InsnNode(InsnType.MERGE, 2);
+						merge.setResult(toReg.duplicate());
+						merge.addArg(toReg.duplicate());
+						merge.addArg(fromReg.duplicate());
+						injectInsn(mth, insertBlock, merge);
+					} else if (liveFromBefore) {
 						// remap variable
-						RegisterArg to = entry.getValue();
 						InsnNode move = new InsnNode(InsnType.MOVE, 1);
-						move.setResult(to);
-						move.addArg(from);
-						insertBlock.getInstructions().add(move);
-					} else if (laAfter.isLive(insertBlock.getId(), regNum)) {
+						move.setResult(toReg.duplicate());
+						move.addArg(fromReg.duplicate());
+						injectInsn(mth, insertBlock, move);
+					} else if (liveFromAfter) {
 						// kill variable
 						InsnNode kill = new InsnNode(InsnType.NOP, 0);
-						kill.setResult(from);
+						kill.setResult(fromReg.duplicate());
 						kill.add(AFlag.REMOVE);
-						insertBlock.getInstructions().add(0, kill);
+						injectInsn(mth, insertBlock, kill);
 					}
-					processed.set(regNum);
+					processed.set(fromRegNum);
 				}
 			}
 		}
 	}
 
+	private static void injectInsn(MethodNode mth, BlockNode insertBlock, InsnNode insn) {
+		insn.add(AFlag.SYNTHETIC);
+		if (insertBlock.getInstructions().isEmpty()) {
+			insertBlock.getInstructions().add(insn);
+		} else {
+			BlockNode succBlock = splitBlock(mth, insertBlock, 0);
+			BlockNode predBlock = succBlock.getPredecessors().get(0);
+			predBlock.getInstructions().add(insn);
+		}
+	}
+
 	private static boolean isReMapNeeded(List<BlocksRemoveInfo> removes) {
 		for (BlocksRemoveInfo removeInfo : removes) {
 			if (!removeInfo.getRegMap().isEmpty()) {
@@ -270,11 +295,41 @@ public class BlockFinallyExtract extends AbstractVisitor {
 		if (removeInfo == null) {
 			return null;
 		}
-		if (removeInfo.getOuts().size() != 1) {
-			LOG.debug("Unexpected finally block outs count: {}", removeInfo.getOuts());
-			return null;
+		Set<BlocksPair> outs = removeInfo.getOuts();
+		if (outs.size() == 1) {
+			return removeInfo;
 		}
-		return removeInfo;
+		// check if several 'return' blocks maps to one out
+		if (mergeReturns(mth, outs)) {
+			return removeInfo;
+		}
+		LOG.debug("Unexpected finally block outs count: {}", outs);
+		return null;
+	}
+
+	private static boolean mergeReturns(MethodNode mth, Set<BlocksPair> outs) {
+		Set<BlockNode> rightOuts = new HashSet<BlockNode>();
+		boolean allReturns = true;
+		for (BlocksPair outPair : outs) {
+			BlockNode first = outPair.getFirst();
+			if (!first.isReturnBlock()) {
+				allReturns = false;
+			}
+			rightOuts.add(outPair.getSecond());
+		}
+		if (!allReturns || rightOuts.size() != 1) {
+			return false;
+		}
+		Iterator<BlocksPair> it = outs.iterator();
+		while (it.hasNext()) {
+			BlocksPair out = it.next();
+			BlockNode returnBlock = out.getFirst();
+			if (!returnBlock.contains(AFlag.ORIG_RETURN)) {
+				markForRemove(mth, returnBlock);
+				it.remove();
+			}
+		}
+		return true;
 	}
 
 	private static BlocksRemoveInfo checkFromFirstBlock(BlockNode remBlock, BlockNode startBlock, BitSet bs) {
@@ -453,7 +508,7 @@ public class BlockFinallyExtract extends AbstractVisitor {
 			// change start block in removeInfo
 			removeInfo.getProcessed().remove(removeInfo.getStart());
 			BlocksPair newStart = new BlocksPair(remBlock, startBlock);
-			removeInfo.setStart(newStart);
+//			removeInfo.setStart(newStart);
 			removeInfo.getProcessed().add(newStart);
 		}
 		// split end block
@@ -529,6 +584,11 @@ public class BlockFinallyExtract extends AbstractVisitor {
 		return true;
 	}
 
+	/**
+	 * Split one block into connected 2 blocks with same connections.
+	 *
+	 * @return new successor block
+	 */
 	private static BlockNode splitBlock(MethodNode mth, BlockNode block, int splitIndex) {
 		BlockNode newBlock = BlockSplitter.startNewBlock(mth, -1);
 
@@ -654,6 +714,53 @@ public class BlockFinallyExtract extends AbstractVisitor {
 			markForRemove(mth, mb);
 			edgeAttr.getBlocks().remove(mb);
 		}
+		mergeSyntheticPredecessors(mth, origReturnBlock);
+	}
+
+	private static void mergeSyntheticPredecessors(MethodNode mth, BlockNode block) {
+		List<BlockNode> preds = new ArrayList<BlockNode>(block.getPredecessors());
+		Iterator<BlockNode> it = preds.iterator();
+		while (it.hasNext()) {
+			BlockNode predBlock = it.next();
+			if (!predBlock.isSynthetic()) {
+				it.remove();
+			}
+		}
+		if (preds.size() < 2) {
+			return;
+		}
+		BlockNode commonBlock = null;
+		for (BlockNode predBlock : preds) {
+			List<BlockNode> successors = predBlock.getSuccessors();
+			if (successors.size() != 2) {
+				return;
+			}
+			BlockNode cmnBlk = BlockUtils.selectOtherSafe(block, successors);
+			if (commonBlock == null) {
+				commonBlock = cmnBlk;
+			} else if (cmnBlk != commonBlock) {
+				return;
+			}
+			if (!predBlock.contains(AType.IGNORE_EDGE)) {
+				return;
+			}
+		}
+		if (commonBlock == null) {
+			return;
+		}
+
+		// merge confirmed
+		BlockNode mergeBlock = null;
+		for (BlockNode predBlock : preds) {
+			if (mergeBlock == null) {
+				mergeBlock = predBlock;
+				continue;
+			}
+			for (BlockNode remPred : predBlock.getPredecessors()) {
+				connect(remPred, mergeBlock);
+			}
+			markForRemove(mth, predBlock);
+		}
 	}
 
 	private static BlockNode getFinallyOutBlock(List<BlockNode> exitBlocks) {

jadx-core/src/main/java/jadx/core/dex/visitors/regions/IfMakerHelper.java

@@ -24,7 +24,7 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import static jadx.core.dex.visitors.regions.RegionMaker.isEqualPaths;
-import static jadx.core.dex.visitors.regions.RegionMaker.isReturnBlocks;
+import static jadx.core.dex.visitors.regions.RegionMaker.isEqualReturnBlocks;
 import static jadx.core.utils.BlockUtils.getNextBlock;
 import static jadx.core.utils.BlockUtils.isPathExists;
 
@@ -277,7 +277,7 @@ public class IfMakerHelper {
 	}
 
 	private static boolean isSameBlocks(BlockNode first, BlockNode second) {
-		return first == second || isReturnBlocks(first, second);
+		return first == second || isEqualReturnBlocks(first, second);
 	}
 
 	static void confirmMerge(IfInfo info) {

jadx-core/src/main/java/jadx/core/dex/visitors/regions/ProcessVariables.java

@@ -256,17 +256,17 @@ public class ProcessVariables extends AbstractVisitor {
 				continue;
 			}
 			IRegion parent = region;
-			boolean declare = false;
+			boolean declared = false;
 			while (parent != null) {
 				if (canDeclareInRegion(u, region, regionsOrder)) {
 					declareVar(region, u.getArg());
-					declare = true;
+					declared = true;
 					break;
 				}
 				region = parent;
 				parent = region.getParent();
 			}
-			if (!declare) {
+			if (!declared) {
 				declareVar(mth.getRegion(), u.getArg());
 			}
 		}

jadx-core/src/main/java/jadx/core/dex/visitors/regions/RegionMaker.java

@@ -12,6 +12,8 @@ import jadx.core.dex.instructions.SwitchNode;
 import jadx.core.dex.instructions.args.InsnArg;
 import jadx.core.dex.nodes.BlockNode;
 import jadx.core.dex.nodes.Edge;
+import jadx.core.dex.nodes.IBlock;
+import jadx.core.dex.nodes.IContainer;
 import jadx.core.dex.nodes.IRegion;
 import jadx.core.dex.nodes.InsnNode;
 import jadx.core.dex.nodes.MethodNode;
@@ -899,7 +901,7 @@ public class RegionMaker {
 		}
 	}
 
-	public void processTryCatchBlocks(MethodNode mth) {
+	public IRegion processTryCatchBlocks(MethodNode mth) {
 		Set<TryCatchBlock> tcs = new HashSet<TryCatchBlock>();
 		for (ExceptionHandler handler : mth.getExceptionHandlers()) {
 			tcs.add(handler.getTryBlock());
@@ -935,6 +937,40 @@ public class RegionMaker {
 				processExcHandler(handler, exits);
 			}
 		}
+		return processHandlersOutBlocks(mth, tcs);
+	}
+
+	/**
+	 * Search handlers successor blocks not included in any region.
+	 */
+	protected IRegion processHandlersOutBlocks(MethodNode mth, Set<TryCatchBlock> tcs) {
+		Set<IBlock> allRegionBlocks = new HashSet<IBlock>();
+		RegionUtils.getAllRegionBlocks(mth.getRegion(), allRegionBlocks);
+
+		Set<IBlock> succBlocks = new HashSet<IBlock>();
+		for (TryCatchBlock tc : tcs) {
+			for (ExceptionHandler handler : tc.getHandlers()) {
+				IContainer region = handler.getHandlerRegion();
+				if (region != null) {
+					IBlock lastBlock = RegionUtils.getLastBlock(region);
+					if (lastBlock instanceof BlockNode) {
+						succBlocks.addAll(((BlockNode) lastBlock).getSuccessors());
+					}
+					RegionUtils.getAllRegionBlocks(region, allRegionBlocks);
+				}
+			}
+		}
+		succBlocks.removeAll(allRegionBlocks);
+		if (succBlocks.isEmpty()) {
+			return null;
+		}
+		Region excOutRegion = new Region(mth.getRegion());
+		for (IBlock block : succBlocks) {
+			if (block instanceof BlockNode) {
+				excOutRegion.add(makeRegion((BlockNode) block, new RegionStack(mth)));
+			}
+		}
+		return excOutRegion;
 	}
 
 	private void processExcHandler(ExceptionHandler handler, Set<BlockNode> exits) {
@@ -980,7 +1016,7 @@ public class RegionMaker {
 		if (b1 == null || b2 == null) {
 			return false;
 		}
-		return isReturnBlocks(b1, b2) || isSyntheticPath(b1, b2);
+		return isEqualReturnBlocks(b1, b2) || isSyntheticPath(b1, b2);
 	}
 
 	private static boolean isSyntheticPath(BlockNode b1, BlockNode b2) {
@@ -989,7 +1025,7 @@ public class RegionMaker {
 		return (n1 != b1 || n2 != b2) && isEqualPaths(n1, n2);
 	}
 
-	public static boolean isReturnBlocks(BlockNode b1, BlockNode b2) {
+	public static boolean isEqualReturnBlocks(BlockNode b1, BlockNode b2) {
 		if (!b1.isReturnBlock() || !b2.isReturnBlock()) {
 			return false;
 		}

jadx-core/src/main/java/jadx/core/dex/visitors/regions/RegionMakerVisitor.java

@@ -49,7 +49,10 @@ public class RegionMakerVisitor extends AbstractVisitor {
 		mth.setRegion(rm.makeRegion(mth.getEnterBlock(), state));
 
 		if (!mth.isNoExceptionHandlers()) {
-			rm.processTryCatchBlocks(mth);
+			IRegion expOutBlock = rm.processTryCatchBlocks(mth);
+			if (expOutBlock != null) {
+				mth.getRegion().add(expOutBlock);
+			}
 		}
 
 		postProcessRegions(mth);

jadx-core/src/main/java/jadx/core/dex/visitors/ssa/EliminatePhiNodes.java

@@ -2,12 +2,17 @@ package jadx.core.dex.visitors.ssa;
 
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.nodes.PhiListAttr;
+import jadx.core.dex.instructions.InsnType;
 import jadx.core.dex.instructions.PhiInsn;
+import jadx.core.dex.instructions.args.RegisterArg;
+import jadx.core.dex.instructions.args.SSAVar;
 import jadx.core.dex.nodes.BlockNode;
 import jadx.core.dex.nodes.InsnNode;
 import jadx.core.dex.nodes.MethodNode;
 import jadx.core.dex.visitors.AbstractVisitor;
+import jadx.core.utils.BlockUtils;
 import jadx.core.utils.exceptions.JadxException;
+import jadx.core.utils.exceptions.JadxRuntimeException;
 
 import java.util.Iterator;
 import java.util.List;
@@ -23,6 +28,7 @@ public class EliminatePhiNodes extends AbstractVisitor {
 		if (mth.isNoCode()) {
 			return;
 		}
+		replaceMergeInstructions(mth);
 		removePhiInstructions(mth);
 	}
 
@@ -50,4 +56,75 @@ public class EliminatePhiNodes extends AbstractVisitor {
 		}
 		LOG.warn("Phi node not removed: {}, mth: {}", phiInsn, mth);
 	}
+
+	private void replaceMergeInstructions(MethodNode mth) {
+		for (BlockNode block : mth.getBasicBlocks()) {
+			List<InsnNode> insns = block.getInstructions();
+			if (insns.isEmpty()) {
+				continue;
+			}
+			InsnNode insn = insns.get(0);
+			if (insn.getType() == InsnType.MERGE) {
+				replaceMerge(mth, block, insn);
+			}
+		}
+	}
+
+	/**
+	 * Replace 'MERGE' with 'PHI' insn.
+	 */
+	private void replaceMerge(MethodNode mth, BlockNode block, InsnNode insn) {
+		if (insn.getArgsCount() != 2) {
+			throw new JadxRuntimeException("Unexpected count of arguments in merge insn: " + insn);
+		}
+		RegisterArg oldArg = (RegisterArg) insn.getArg(1);
+		RegisterArg newArg = (RegisterArg) insn.getArg(0);
+		int newRegNum = newArg.getRegNum();
+		if (oldArg.getRegNum() == newRegNum) {
+			throw new JadxRuntimeException("Unexpected register number in merge insn: " + insn);
+		}
+		SSAVar oldSVar = oldArg.getSVar();
+		RegisterArg assignArg = oldSVar.getAssign();
+
+		InsnNode assignParentInsn = assignArg.getParentInsn();
+		BlockNode assignBlock = BlockUtils.getBlockByInsn(mth, assignParentInsn);
+		if (assignBlock == null) {
+			throw new JadxRuntimeException("Unknown assign block for " + assignParentInsn);
+		}
+		BlockNode assignPred = null;
+		for (BlockNode pred : block.getPredecessors()) {
+			if (BlockUtils.isPathExists(assignBlock, pred)) {
+				assignPred = pred;
+				break;
+			}
+		}
+		if (assignPred == null) {
+			throw new JadxRuntimeException("Assign predecessor not found for " + assignBlock + " from " + block);
+		}
+
+		// all checks passed
+		RegisterArg newAssignArg = oldArg.duplicate(newRegNum, null);
+		SSAVar newSVar = mth.makeNewSVar(newRegNum, mth.getNextSVarVersion(newRegNum), newAssignArg);
+		newSVar.setName(oldSVar.getName());
+		newSVar.setType(assignArg.getType());
+
+		if (assignParentInsn != null) {
+			assignParentInsn.setResult(newAssignArg);
+		}
+		for (RegisterArg useArg : oldSVar.getUseList()) {
+			RegisterArg newUseArg = useArg.duplicate(newRegNum, newSVar);
+			InsnNode parentInsn = useArg.getParentInsn();
+			if (parentInsn != null) {
+				newSVar.use(newUseArg);
+				parentInsn.replaceArg(useArg, newUseArg);
+			}
+		}
+		block.getInstructions().remove(0);
+		PhiInsn phiInsn = SSATransform.addPhi(mth, block, newRegNum);
+		phiInsn.setResult(insn.getResult());
+
+		phiInsn.bindArg(newAssignArg.duplicate(), assignPred);
+		phiInsn.bindArg(newArg.duplicate(),
+				BlockUtils.selectOtherSafe(assignPred, block.getPredecessors()));
+	}
 }

jadx-core/src/main/java/jadx/core/dex/visitors/ssa/LiveVarAnalysis.java

@@ -10,7 +10,12 @@ import jadx.core.utils.exceptions.JadxRuntimeException;
 import java.util.BitSet;
 import java.util.List;
 
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 public class LiveVarAnalysis {
+	private static final Logger LOG = LoggerFactory.getLogger(LiveVarAnalysis.class);
+
 	private final MethodNode mth;
 
 	private BitSet[] uses;
@@ -37,9 +42,17 @@ public class LiveVarAnalysis {
 	}
 
 	public boolean isLive(int blockId, int regNum) {
+		if (blockId >= liveIn.length) {
+			LOG.warn("LiveVarAnalysis: out of bounds block: {}, max: {}", blockId, liveIn.length);
+			return false;
+		}
 		return liveIn[blockId].get(regNum);
 	}
 
+	public boolean isLive(BlockNode block, int regNum) {
+		return isLive(block.getId(), regNum);
+	}
+
 	private void fillBasicBlockInfo() {
 		for (BlockNode block : mth.getBasicBlocks()) {
 			int blockId = block.getId();

jadx-core/src/main/java/jadx/core/dex/visitors/ssa/SSATransform.java

@@ -93,7 +93,7 @@ public class SSATransform extends AbstractVisitor {
 		}
 	}
 
-	private static void addPhi(MethodNode mth, BlockNode block, int regNum) {
+	public static PhiInsn addPhi(MethodNode mth, BlockNode block, int regNum) {
 		PhiListAttr phiList = block.get(AType.PHI_LIST);
 		if (phiList == null) {
 			phiList = new PhiListAttr();
@@ -112,6 +112,7 @@ public class SSATransform extends AbstractVisitor {
 		phiList.getList().add(phiInsn);
 		phiInsn.setOffset(block.getStartOffset());
 		block.getInstructions().add(0, phiInsn);
+		return phiInsn;
 	}
 
 	private static void renameVariables(MethodNode mth) {
@@ -124,13 +125,18 @@ public class SSATransform extends AbstractVisitor {
 		// init method arguments
 		for (RegisterArg arg : mth.getArguments(true)) {
 			int regNum = arg.getRegNum();
-			vars[regNum] = mth.makeNewSVar(regNum, versions, arg);
+			vars[regNum] = newSSAVar(mth, versions, arg, regNum);
 		}
 		BlockNode enterBlock = mth.getEnterBlock();
 		initPhiInEnterBlock(vars, enterBlock);
 		renameVar(mth, vars, versions, enterBlock);
 	}
 
+	private static SSAVar newSSAVar(MethodNode mth, int[] versions, RegisterArg arg, int regNum) {
+		int version = versions[regNum]++;
+		return mth.makeNewSVar(regNum, version, arg);
+	}
+
 	private static void initPhiInEnterBlock(SSAVar[] vars, BlockNode enterBlock) {
 		PhiListAttr phiList = enterBlock.get(AType.PHI_LIST);
 		if (phiList != null) {
@@ -168,7 +174,7 @@ public class SSATransform extends AbstractVisitor {
 			RegisterArg result = insn.getResult();
 			if (result != null) {
 				int regNum = result.getRegNum();
-				vars[regNum] = mth.makeNewSVar(regNum, vers, result);
+				vars[regNum] = newSSAVar(mth, vers, result, regNum);
 			}
 		}
 		for (BlockNode s : block.getSuccessors()) {

jadx-core/src/main/java/jadx/core/dex/visitors/typeinference/PostTypeInference.java

@@ -3,7 +3,6 @@ package jadx.core.dex.visitors.typeinference;
 import jadx.core.dex.info.MethodInfo;
 import jadx.core.dex.instructions.IndexInsnNode;
 import jadx.core.dex.instructions.InvokeNode;
-import jadx.core.dex.instructions.PhiInsn;
 import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.instructions.args.InsnArg;
 import jadx.core.dex.instructions.args.LiteralArg;
@@ -101,11 +100,11 @@ public class PostTypeInference {
 				return true;
 			}
 
-			case PHI: {
-				PhiInsn phi = (PhiInsn) insn;
-				ArgType type = phi.getResult().getType();
+			case PHI:
+			case MERGE: {
+				ArgType type = insn.getResult().getType();
 				if (!type.isTypeKnown()) {
-					for (InsnArg arg : phi.getArguments()) {
+					for (InsnArg arg : insn.getArguments()) {
 						if (arg.getType().isTypeKnown()) {
 							type = arg.getType();
 							break;
@@ -113,11 +112,11 @@ public class PostTypeInference {
 					}
 				}
 				boolean changed = false;
-				if (updateType(phi.getResult(), type)) {
+				if (updateType(insn.getResult(), type)) {
 					changed = true;
 				}
-				for (int i = 0; i < phi.getArgsCount(); i++) {
-					RegisterArg arg = phi.getArg(i);
+				for (int i = 0; i < insn.getArgsCount(); i++) {
+					RegisterArg arg = (RegisterArg) insn.getArg(i);
 					if (updateType(arg, type)) {
 						changed = true;
 					}

jadx-core/src/main/java/jadx/core/utils/DebugUtils.java

@@ -36,7 +36,11 @@ public class DebugUtils {
 	private static final Logger LOG = LoggerFactory.getLogger(DebugUtils.class);
 
 	public static void dump(MethodNode mth) {
-		File out = new File("test-graph-tmp");
+		dump(mth, "");
+	}
+
+	public static void dump(MethodNode mth, String desc) {
+		File out = new File("test-graph" + desc + "-tmp");
 		DotGraphVisitor.dump(out).visit(mth);
 		DotGraphVisitor.dumpRaw(out).visit(mth);
 		DotGraphVisitor.dumpRegions(out).visit(mth);

jadx-core/src/main/java/jadx/core/utils/RegionUtils.java

@@ -72,6 +72,22 @@ public class RegionUtils {
 		}
 	}
 
+	public static IBlock getLastBlock(IContainer container) {
+		if (container instanceof IBlock) {
+			return (IBlock) container;
+		} else if (container instanceof IBranchRegion) {
+			return null;
+		} else if (container instanceof IRegion) {
+			List<IContainer> blocks = ((IRegion) container).getSubBlocks();
+			if (blocks.isEmpty()) {
+				return null;
+			}
+			return getLastBlock(blocks.get(blocks.size() - 1));
+		} else {
+			throw new JadxRuntimeException(unknownContainerType(container));
+		}
+	}
+
 	/**
 	 * Return true if last block in region has no successors
 	 */

jadx-core/src/test/java/jadx/tests/integration/trycatch/TestTryCatchFinally6.java

+package jadx.tests.integration.trycatch;
+
+import jadx.core.dex.nodes.ClassNode;
+import jadx.tests.api.IntegrationTest;
+
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+
+import org.junit.Test;
+
+import static jadx.tests.api.utils.JadxMatchers.containsLines;
+import static org.junit.Assert.assertThat;
+
+public class TestTryCatchFinally6 extends IntegrationTest {
+
+	public static class TestCls {
+		public static void test() throws IOException {
+			InputStream is = null;
+			try {
+				is = new FileInputStream("1.txt");
+			} finally {
+				if (is != null) {
+					is.close();
+				}
+			}
+		}
+	}
+
+	@Test
+	public void test() {
+		ClassNode cls = getClassNode(TestCls.class);
+		String code = cls.getCode().toString();
+
+		assertThat(code, containsLines(2,
+				"InputStream is = null;",
+				"try {",
+				indent(1) + "is = new FileInputStream(\"1.txt\");",
+				"} finally {",
+				indent(1) + "if (is != null) {",
+				indent(2) + "is.close();",
+				indent(1) + "}",
+				"}"
+		));
+	}
+}