core: fixed types for arguments from overloaded methods

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

@@ -523,7 +523,29 @@ public class InsnGen {
 				break;
 		}
 		code.add(callMth.getName());
-		addArgs(code, insn, k);
+		if (callMthNode != null && callMthNode.isArgsOverload()) {
+			int argsCount = insn.getArgsCount();
+			List<ArgType> originalType = callMth.getArgumentsTypes();
+			int origPos = 0;
+
+			code.add('(');
+			for (int i = k; i < argsCount; i++) {
+				InsnArg arg = insn.getArg(i);
+				ArgType origType = originalType.get(origPos);
+				if (!arg.getType().equals(origType)) {
+					code.add('(').add(useType(origType)).add(')').add(arg(arg));
+				} else {
+					code.add(arg(arg));
+				}
+				if (i < argsCount - 1) {
+					code.add(", ");
+				}
+				origPos++;
+			}
+			code.add(')');
+		} else {
+			addArgs(code, insn, k);
+		}
 	}
 
 	private void inlineMethod(MethodNode callMthNode, InvokeNode insn, CodeWriter code) throws CodegenException {
@@ -566,11 +588,14 @@ public class InsnGen {
 	}
 
 	private void addArgs(CodeWriter code, InsnNode insn, int k) throws CodegenException {
+		int argsCount = insn.getArgsCount();
 		code.add('(');
-		for (int i = k; i < insn.getArgsCount(); i++) {
-			code.add(arg(insn, i));
-			if (i < insn.getArgsCount() - 1)
+		if (k < argsCount) {
+			code.add(arg(insn, k));
+			for (int i = k + 1; i < argsCount; i++) {
 				code.add(", ");
+				code.add(arg(insn, i));
+			}
 		}
 		code.add(')');
 	}

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

@@ -455,8 +455,23 @@ public class MethodNode extends LineAttrNode implements ILoadable {
 		return exceptionHandlers;
 	}
 
-	public boolean isMethodOverloaded() {
-		// TODO
+	/**
+	 * Return true if exists method with same name and arguments count
+	 */
+	public boolean isArgsOverload() {
+		int argsCount = mthInfo.getArgumentsTypes().size();
+		if (argsCount == 0) {
+			return false;
+		}
+
+		String name = getName();
+		List<MethodNode> methods = parentClass.getMethods();
+		for (MethodNode method : methods) {
+			if (this != method
+					&& method.getName().equals(name)
+					&& method.mthInfo.getArgumentsTypes().size() == argsCount)
+				return true;
+		}
 		return false;
 	}
 

jadx-core/src/main/java/jadx/core/dex/visitors/typeresolver/FinishTypeResolver.java

@@ -19,11 +19,11 @@ public class FinishTypeResolver extends AbstractVisitor {
 		int i = 0;
 		do {
 			change = false;
-			for (BlockNode block : mth.getBasicBlocks())
+			for (BlockNode block : mth.getBasicBlocks()) {
 				for (InsnNode insn : block.getInstructions())
-					if (PostTypeResolver.visit(insn))
+					if (PostTypeResolver.visit(mth, insn))
 						change = true;
-
+			}
 			i++;
 			if (i > 1000)
 				break;

jadx-core/src/main/java/jadx/core/dex/visitors/typeresolver/finish/PostTypeResolver.java

 package jadx.core.dex.visitors.typeresolver.finish;
 
+import jadx.core.dex.info.MethodInfo;
 import jadx.core.dex.instructions.IfNode;
+import jadx.core.dex.instructions.InvokeNode;
 import jadx.core.dex.instructions.args.ArgType;
 import jadx.core.dex.instructions.args.InsnArg;
 import jadx.core.dex.instructions.args.LiteralArg;
 import jadx.core.dex.instructions.args.RegisterArg;
 import jadx.core.dex.nodes.InsnNode;
+import jadx.core.dex.nodes.MethodNode;
+
+import java.util.List;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public class PostTypeResolver {
+	private static final Logger LOG = LoggerFactory.getLogger(PostTypeResolver.class);
 
-	public static boolean visit(InsnNode insn) {
+	public static boolean visit(MethodNode mth, InsnNode insn) {
 		switch (insn.getType()) {
 			case CONST:
-				if (insn.getArgsCount() > 0) {
-					RegisterArg res = insn.getResult();
-					LiteralArg litArg = (LiteralArg) insn.getArg(0);
-					if (res.getType().isObject()) {
-						long lit = litArg.getLiteral();
-						if (lit != 0) {
-							// incorrect literal value for object
-							ArgType type = (lit == 1 ? ArgType.BOOLEAN : ArgType.INT);
-							// can't merge with object -> force it
-							litArg.getTypedVar().forceSetType(type);
-							res.getTypedVar().forceSetType(type);
-							return true;
-						}
+				RegisterArg res = insn.getResult();
+				LiteralArg litArg = (LiteralArg) insn.getArg(0);
+				if (res.getType().isObject()) {
+					long lit = litArg.getLiteral();
+					if (lit != 0) {
+						// incorrect literal value for object
+						ArgType type = (lit == 1 ? ArgType.BOOLEAN : ArgType.INT);
+						// can't merge with object -> force it
+						litArg.getTypedVar().forceSetType(type);
+						res.getTypedVar().forceSetType(type);
+						return true;
 					}
-					// return litArg.getTypedVar().forceSetType(res.getType());
-					return litArg.merge(res);
 				}
-				break;
+				// return litArg.getTypedVar().forceSetType(res.getType());
+				return litArg.merge(res);
 
 			case MOVE: {
 				boolean change = false;
@@ -58,6 +64,27 @@ public class PostTypeResolver {
 				return change;
 			}
 
+			// check argument types for overloaded methods
+			case INVOKE: {
+				boolean change = false;
+				InvokeNode inv = (InvokeNode) insn;
+				MethodInfo callMth = inv.getCallMth();
+				MethodNode node = mth.dex().resolveMethod(callMth);
+				if (node != null && node.isArgsOverload()) {
+					List<ArgType> args = callMth.getArgumentsTypes();
+					int j = inv.getArgsCount() - 1;
+					for (int i = args.size() - 1; i >= 0; i--) {
+						ArgType argType = args.get(i);
+						InsnArg insnArg = inv.getArg(j--);
+						if (insnArg.isRegister() && !argType.equals(insnArg.getType())) {
+							insnArg.getTypedVar().forceSetType(argType);
+							change = true;
+						}
+					}
+				}
+				return change;
+			}
+
 			default:
 				break;
 		}

jadx-samples/src/main/java/jadx/samples/TestTypeResolver2.java

+package jadx.samples;
+
+/**
+ * Code example from
+ * <a href="http://stackoverflow.com/questions/2840183/is-there-any-java-decompiler-that-can-correctly-decompile-calls-to-overloaded-me">
+ * stackoverflow question</a>
+ */
+public class TestTypeResolver2 extends AbstractTest {
+
+	private static String result  = "";
+
+	public void testOverloadedMethods() {
+		Object s1 = "The";
+		Object s2 = "answer";
+		doPrint((Object) "You should know:");
+		for (int i = 0; i < 2; i++) {
+			doPrint(s1);
+			doPrint(s2);
+			s1 = "is";
+			s2 = new Integer(42);
+		}
+	}
+
+	private static void doPrint(String s1) {
+		// incorrect call
+		assertTrue(false);
+	}
+
+	private static void doPrint(Integer s1) {
+		// incorrect call
+		assertTrue(false);
+	}
+
+	private static void doPrint(Object s1) {
+		// correct call
+		result += s1 + " ";
+	}
+
+	@Override
+	public boolean testRun() throws Exception {
+		testOverloadedMethods();
+
+		assertEquals(result, "You should know: The answer is 42 ");
+		return true;
+	}
+
+	public static void main(String[] args) throws Exception {
+		(new TestTypeResolver2()).testRun();
+	}
+}