Fix try/catch/finally block processing

src/main/java/jadx/dex/trycatch/ExceptionHandler.java

@@ -2,7 +2,7 @@ package jadx.dex.trycatch;
 
 import jadx.Consts;
 import jadx.dex.info.ClassInfo;
-import jadx.dex.instructions.args.InsnArg;
+import jadx.dex.instructions.args.RegisterArg;
 import jadx.dex.nodes.BlockNode;
 import jadx.dex.nodes.IContainer;
 import jadx.utils.InsnUtils;
@@ -18,7 +18,9 @@ public class ExceptionHandler {
 	private BlockNode handleBlock;
 	private final List<BlockNode> blocks = new ArrayList<BlockNode>();
 	private IContainer handlerRegion;
-	private InsnArg arg;
+	private RegisterArg arg;
+
+	private TryCatchBlock tryBlock;
 
 	public ExceptionHandler(int addr, ClassInfo type) {
 		this.handleOffset = addr;
@@ -61,14 +63,22 @@ public class ExceptionHandler {
 		this.handlerRegion = handlerRegion;
 	}
 
-	public InsnArg getArg() {
+	public RegisterArg getArg() {
 		return arg;
 	}
 
-	public void setArg(InsnArg arg) {
+	public void setArg(RegisterArg arg) {
 		this.arg = arg;
 	}
 
+	public void setTryBlock(TryCatchBlock tryBlock) {
+		this.tryBlock = tryBlock;
+	}
+
+	public TryCatchBlock getTryBlock() {
+		return tryBlock;
+	}
+
 	@Override
 	public int hashCode() {
 		return (catchType == null ? 0 : 31 * catchType.hashCode()) + handleOffset;

src/main/java/jadx/dex/trycatch/TryCatchBlock.java

 package jadx.dex.trycatch;
 
 import jadx.dex.attributes.AttributeType;
+import jadx.dex.attributes.IAttribute;
 import jadx.dex.info.ClassInfo;
 import jadx.dex.nodes.BlockNode;
+import jadx.dex.nodes.IBlock;
 import jadx.dex.nodes.IContainer;
+import jadx.dex.nodes.InsnContainer;
 import jadx.dex.nodes.InsnNode;
 import jadx.dex.nodes.MethodNode;
+import jadx.dex.visitors.InstructionRemover;
 import jadx.utils.Utils;
 
 import java.util.ArrayList;
@@ -36,6 +40,7 @@ public class TryCatchBlock {
 		ExceptionHandler handler = new ExceptionHandler(addr, type);
 		handler = mth.addExceptionHandler(handler);
 		handlers.add(handler);
+		handler.setTryBlock(this);
 		return handler;
 	}
 
@@ -52,14 +57,29 @@ public class TryCatchBlock {
 	}
 
 	private void removeWholeBlock(MethodNode mth) {
+		if (finalBlock != null) {
+			// search catch attr
+			for (BlockNode block : mth.getBasicBlocks()) {
+				CatchAttr cb = (CatchAttr) block.getAttributes().get(AttributeType.CATCH_BLOCK);
+				if (cb == attr) {
+					for (ExceptionHandler eh : mth.getExceptionHandlers()) {
+						if (eh.getBlocks().contains(block)) {
+							TryCatchBlock tb = eh.getTryBlock();
+							tb.setFinalBlockFromInsns(mth, ((IBlock) finalBlock).getInstructions());
+						}
+					}
+				}
+			}
+			return;
+		}
+
 		// self destruction
 		for (InsnNode insn : insns)
-			insn.getAttributes().remove(AttributeType.CATCH_BLOCK);
+			insn.getAttributes().remove(attr);
 
 		insns.clear();
-		for (BlockNode block : mth.getBasicBlocks()) {
-			block.getAttributes().remove(AttributeType.CATCH_BLOCK);
-		}
+		for (BlockNode block : mth.getBasicBlocks())
+			block.getAttributes().remove(attr);
 	}
 
 	public void addInsn(InsnNode insn) {
@@ -92,11 +112,34 @@ public class TryCatchBlock {
 		this.finalBlock = finalBlock;
 	}
 
+	public void setFinalBlockFromInsns(MethodNode mth, List<InsnNode> insns) {
+		InsnContainer cont = new InsnContainer();
+		List<InsnNode> finalBlockInsns = new ArrayList<InsnNode>(insns);
+		cont.setInstructions(finalBlockInsns);
+		setFinalBlock(cont);
+
+		InstructionRemover.unbindInsnList(finalBlockInsns);
+
+		// remove these instructions from other handlers
+		for (ExceptionHandler h : getHandlers()) {
+			for (BlockNode ehb : h.getBlocks())
+				ehb.getInstructions().removeAll(finalBlockInsns);
+		}
+		// remove from blocks with this catch
+		for (BlockNode b : mth.getBasicBlocks()) {
+			IAttribute ca = b.getAttributes().get(AttributeType.CATCH_BLOCK);
+			if (attr == ca)
+				b.getInstructions().removeAll(finalBlockInsns);
+		}
+	}
+
 	public void merge(MethodNode mth, TryCatchBlock tryBlock) {
 		for (InsnNode insn : tryBlock.getInsns())
 			this.addInsn(insn);
 
 		this.handlers.addAll(tryBlock.getHandlers());
+		for (ExceptionHandler eh : handlers)
+			eh.setTryBlock(this);
 
 		// clear
 		tryBlock.handlers.clear();

src/main/java/jadx/dex/visitors/ModVisitor.java

@@ -2,7 +2,6 @@ package jadx.dex.visitors;
 
 import jadx.Consts;
 import jadx.dex.attributes.AttributeType;
-import jadx.dex.attributes.IAttribute;
 import jadx.dex.info.MethodInfo;
 import jadx.dex.instructions.IndexInsnNode;
 import jadx.dex.instructions.InsnType;
@@ -12,7 +11,6 @@ import jadx.dex.instructions.args.RegisterArg;
 import jadx.dex.instructions.mods.ConstructorInsn;
 import jadx.dex.nodes.BlockNode;
 import jadx.dex.nodes.FieldNode;
-import jadx.dex.nodes.InsnContainer;
 import jadx.dex.nodes.InsnNode;
 import jadx.dex.nodes.MethodNode;
 import jadx.dex.trycatch.ExcHandlerAttr;
@@ -21,7 +19,6 @@ import jadx.dex.trycatch.TryCatchBlock;
 import jadx.utils.BlockUtils;
 import jadx.utils.exceptions.JadxRuntimeException;
 
-import java.util.ArrayList;
 import java.util.List;
 
 import org.slf4j.Logger;
@@ -195,24 +192,8 @@ public class ModVisitor extends AbstractVisitor {
 
 				// move not removed instructions to 'finally' block
 				if (size != 0) {
-					InsnContainer cont = new InsnContainer();
-					List<InsnNode> finalBlockInsns = new ArrayList<InsnNode>(insns);
-					cont.setInstructions(finalBlockInsns);
-					tryBlock.setFinalBlock(cont);
-
-					InstructionRemover.unbindInsnList(finalBlockInsns);
-
-					// remove these instructions from other handlers
-					for (ExceptionHandler h : tryBlock.getHandlers()) {
-						for (BlockNode ehb : h.getBlocks())
-							ehb.getInstructions().removeAll(finalBlockInsns);
-					}
-					// remove from blocks with this catch
-					for (BlockNode b : mth.getBasicBlocks()) {
-						IAttribute ca = b.getAttributes().get(AttributeType.CATCH_BLOCK);
-						if (tryBlock.getCatchAttr() == ca)
-							b.getInstructions().removeAll(finalBlockInsns);
-					}
+					// TODO: support instructions from several blocks
+					tryBlock.setFinalBlockFromInsns(mth, insns);
 					size = insns.size();
 				}
 			}

src/samples/java/jadx/samples/TestTryCatch.java

@@ -118,6 +118,31 @@ public class TestTryCatch extends AbstractTest {
 		}
 	}
 
+	private boolean test8(Object obj) {
+		this.mDiscovering = false;
+		try {
+			exc(obj);
+		} catch (Exception e) {
+			e.toString();
+		} finally {
+			mDiscovering = true;
+		}
+		return mDiscovering;
+	}
+
+	private boolean test8a(Object obj) {
+		this.mDiscovering = false;
+		try {
+			exc(obj);
+		} catch (Exception e) {
+			e.toString();
+		} finally {
+			if (!mDiscovering)
+				mDiscovering = true;
+		}
+		return mDiscovering;
+	}
+
 	private static boolean testSynchronize(Object obj) throws InterruptedException {
 		synchronized (obj) {
 			if (obj instanceof String)
@@ -127,6 +152,7 @@ public class TestTryCatch extends AbstractTest {
 		return true;
 	}
 
+	// TODO: remove 'synchronized(TestTryCatch.class)' block in decompiled version
 	private synchronized static boolean testSynchronize2(Object obj) throws InterruptedException {
 		return obj.toString() != null;
 	}
@@ -159,6 +185,12 @@ public class TestTryCatch extends AbstractTest {
 
 		assertTrue(testSynchronize2("str"));
 		assertTrue(testSynchronize3());
+
+		assertTrue(test8("a"));
+		assertTrue(test8(null));
+
+		assertTrue(test8a("a"));
+		assertTrue(test8a(null));
 		return true;
 	}