fix: improve error reporting for instruction decode failure (#1046)

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

@@ -16,6 +16,7 @@ import jadx.core.Jadx;
 import jadx.core.dex.attributes.AFlag;
 import jadx.core.dex.attributes.AType;
 import jadx.core.dex.attributes.annotations.MethodParameters;
+import jadx.core.dex.attributes.nodes.JadxError;
 import jadx.core.dex.attributes.nodes.JumpInfo;
 import jadx.core.dex.attributes.nodes.MethodOverrideAttr;
 import jadx.core.dex.info.AccessInfo;
@@ -323,6 +324,12 @@ public class MethodGen {
 			if (insn == null) {
 				continue;
 			}
+			if (insn.contains(AType.JADX_ERROR)) {
+				for (JadxError error : insn.getAll(AType.JADX_ERROR)) {
+					code.startLine("// ").add(error.getError());
+				}
+				continue;
+			}
 			if (option != BLOCK_DUMP && needLabel(insn, prevInsn)) {
 				code.decIndent();
 				code.startLine(getLabelName(insn.getOffset()) + ':');

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

@@ -9,6 +9,8 @@ import jadx.api.plugins.input.insns.InsnData;
 import jadx.api.plugins.input.insns.custom.IArrayPayload;
 import jadx.api.plugins.input.insns.custom.ISwitchPayload;
 import jadx.core.Consts;
+import jadx.core.dex.attributes.AType;
+import jadx.core.dex.attributes.nodes.JadxError;
 import jadx.core.dex.info.FieldInfo;
 import jadx.core.dex.info.MethodInfo;
 import jadx.core.dex.instructions.args.ArgType;
@@ -40,11 +42,12 @@ public class InsnDecoder {
 			try {
 				rawInsn.decode();
 				insn = decode(rawInsn);
-				insn.setOffset(offset);
 			} catch (Exception e) {
-				LOG.error("Failed to decode insn: " + rawInsn + ", method: " + method, e);
+				method.addError("Failed to decode insn: " + rawInsn + ", method: " + method, e);
 				insn = new InsnNode(InsnType.NOP, 0);
+				insn.addAttr(AType.JADX_ERROR, new JadxError("decode failed: " + e.getMessage(), e));
 			}
+			insn.setOffset(offset);
 			instructions[offset] = insn;
 		});
 		return instructions;

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

@@ -182,6 +182,17 @@ public class Utils {
 			}
 			prevElement = stackTraceElement;
 		}
+		// stop condition not found -> just cut tail to any jadx class
+		for (int i = length - 1; i >= 0; i--) {
+			String clsName = stackTrace[i].getClassName();
+			if (clsName.startsWith("jadx.")) {
+				if (clsName.startsWith("jadx.tests.")) {
+					continue;
+				}
+				th.setStackTrace(Arrays.copyOfRange(stackTrace, 0, i));
+				return;
+			}
+		}
 	}
 
 	public static <T, R> List<R> collectionMap(Collection<T> list, Function<T, R> mapFunc) {