core: fix various processing issues

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

@@ -5,6 +5,7 @@ import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.AttrNode;
 import jadx.core.dex.attributes.nodes.IgnoreEdgeAttr;
 import jadx.core.dex.attributes.nodes.LoopInfo;
+import jadx.core.utils.EmptyBitSet;
 import jadx.core.utils.InsnUtils;
 
 import java.util.ArrayList;
@@ -24,7 +25,7 @@ public class BlockNode extends AttrNode implements IBlock {
 	private List<BlockNode> cleanSuccessors;
 
 	// all dominators
-	private BitSet doms;
+	private BitSet doms = EmptyBitSet.EMPTY;
 	// dominance frontier
 	private BitSet domFrontier;
 	// immediate dominator

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

@@ -126,9 +126,11 @@ public class MethodNode extends LineAttrNode implements ILoadable {
 				list.add(resultArg);
 			}
 			insnNode.getRegisterArgs(list);
-			for (int i = 0, listSize = list.size(); i < listSize; i++) {
+			int argsCount = list.size();
+			for (int i = 0; i < argsCount; i++) {
 				if (list.get(i).getRegNum() >= regsCount) {
-					throw new JadxRuntimeException("Incorrect register number in instruction: " + insnNode);
+					throw new JadxRuntimeException("Incorrect register number in instruction: " + insnNode
+							+ ", expected to be less than " + regsCount);
 				}
 			}
 		}

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

@@ -106,13 +106,17 @@ public class ConstInlineVisitor extends AbstractVisitor {
 				continue;
 			}
 			LiteralArg litArg;
+			ArgType argType = arg.getType();
+			if (argType.isObject() && literal != 0) {
+				argType = ArgType.NARROW_NUMBERS;
+			}
 			if (use.size() == 1 || arg.isTypeImmutable()) {
 				// arg used only in one place
-				litArg = InsnArg.lit(literal, arg.getType());
+				litArg = InsnArg.lit(literal, argType);
 			} else if (useInsn.getType() == InsnType.MOVE
 					&& !useInsn.getResult().getType().isTypeKnown()) {
 				// save type for 'move' instructions (hard to find type in chains of 'move')
-				litArg = InsnArg.lit(literal, arg.getType());
+				litArg = InsnArg.lit(literal, argType);
 			} else {
 				// in most cases type not equal arg.getType()
 				// just set unknown type and run type fixer

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

@@ -912,7 +912,11 @@ public class RegionMaker {
 		handler.setHandlerRegion(makeRegion(start, stack));
 
 		ExcHandlerAttr excHandlerAttr = start.get(AType.EXC_HANDLER);
-		handler.getHandlerRegion().addAttr(excHandlerAttr);
+		if (excHandlerAttr == null) {
+			LOG.warn("Missing exception handler attribute for start block");
+		} else {
+			handler.getHandlerRegion().addAttr(excHandlerAttr);
+		}
 	}
 
 	static boolean isEqualPaths(BlockNode b1, BlockNode b2) {

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

@@ -88,8 +88,10 @@ public class PostTypeInference {
 			case CHECK_CAST: {
 				ArgType castType = (ArgType) ((IndexInsnNode) insn).getIndex();
 				RegisterArg result = insn.getResult();
+				ArgType resultType = result.getType();
 				// don't override generic types of same base class
-				boolean skip = castType.isObject() && castType.getObject().equals(result.getType().getObject());
+				boolean skip = castType.isObject() && resultType.isObject()
+						&& castType.getObject().equals(resultType.getObject());
 				if (!skip) {
 					// workaround for compiler bug (see TestDuplicateCast)
 					result.getSVar().setType(castType);

jadx-gui/src/main/java/jadx/gui/settings/JadxSettings.java

@@ -18,7 +18,7 @@ public class JadxSettings extends JadxCLIArgs {
 	private static final Font DEFAULT_FONT = new JLabel().getFont();
 
 	static final Set<String> SKIP_FIELDS = new HashSet<String>(Arrays.asList(
-			"files", "input", "outputDir", "printHelp"
+			"files", "input", "outputDir", "verbose", "printHelp"
 	));
 
 	private String lastOpenFilePath = USER_HOME;