core: fix inline in 'move' instruction

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

@@ -24,10 +24,6 @@ public class InsnNode extends LineAttrNode {
 	protected int offset;
 	protected int insnHashCode = super.hashCode();
 
-	protected InsnNode(InsnType type) {
-		this(type, 1);
-	}
-
 	public InsnNode(InsnType type, int argsCount) {
 		this.insnType = type;
 		this.offset = -1;
@@ -155,8 +151,10 @@ public class InsnNode extends LineAttrNode {
 			case STR_CONCAT:
 			case MOVE_EXCEPTION:
 				return true;
+
+			default:
+				return false;
 		}
-		return false;
 	}
 
 	@Override

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

@@ -16,6 +16,11 @@ import jadx.core.utils.exceptions.JadxException;
 import java.util.Iterator;
 import java.util.List;
 
+/**
+ * Prepare instructions for code generation pass,
+ * most of this modification breaks register dependencies,
+ * so this pass must be just before CodeGen.
+ */
 public class PrepareForCodeGen extends AbstractVisitor {
 
 	@Override
@@ -26,7 +31,8 @@ public class PrepareForCodeGen extends AbstractVisitor {
 		}
 		for (BlockNode block : blocks) {
 			removeInstructions(block);
-			removeBrackets(block);
+			checkInline(block);
+			removeParenthesis(block);
 			modifyArith(block);
 		}
 	}
@@ -52,12 +58,31 @@ public class PrepareForCodeGen extends AbstractVisitor {
 		}
 	}
 
-	private static void removeBrackets(BlockNode block) {
+	private static void checkInline(BlockNode block) {
+		List<InsnNode> list = block.getInstructions();
+		for (int i = 0; i < list.size(); i++) {
+			InsnNode insn = list.get(i);
+			// replace 'move' with inner wrapped instruction
+			if (insn.getType() == InsnType.MOVE
+					&& insn.getArg(0).isInsnWrap()
+					&& !insn.getAttributes().contains(AttributeFlag.DECLARE_VAR)) {
+				InsnNode wrapInsn = ((InsnWrapArg)insn.getArg(0)).getWrapInsn();
+				wrapInsn.setResult(insn.getResult());
+				list.set(i, wrapInsn);
+			}
+		}
+	}
+
+	private static void removeParenthesis(BlockNode block) {
 		for (InsnNode insn : block.getInstructions()) {
 			checkInsn(insn);
 		}
 	}
 
+	/**
+	 * Remove parenthesis for wrapped insn  in arith '+' or '-'
+	 * ('(a + b) +c' => 'a + b + c')
+	 */
 	private static void checkInsn(InsnNode insn) {
 		if (insn.getType() == InsnType.ARITH) {
 			ArithNode arith = (ArithNode) insn;
@@ -82,6 +107,10 @@ public class PrepareForCodeGen extends AbstractVisitor {
 		}
 	}
 
+	/**
+	 * Replace arithmetic operation with short form
+	 * ('a = a + 2' => 'a += 2')
+	 */
 	private static void modifyArith(BlockNode block) {
 		List<InsnNode> list = block.getInstructions();
 		for (int i = 0; i < list.size(); i++) {

jadx-core/src/test/java/jadx/tests/internal/TestArgInline.java

@@ -3,6 +3,8 @@ package jadx.tests.internal;
 import jadx.api.InternalJadxTest;
 import jadx.core.dex.nodes.ClassNode;
 
+import org.junit.Test;
+
 import static org.hamcrest.CoreMatchers.containsString;
 import static org.hamcrest.CoreMatchers.not;
 import static org.junit.Assert.assertThat;
@@ -19,12 +21,13 @@ public class TestArgInline extends InternalJadxTest {
 		}
 	}
 
-	//@Test
+	@Test
 	public void test() {
 		ClassNode cls = getClassNode(TestCls.class);
 		String code = cls.getCode().toString();
 		System.out.println(code);
-		assertThat(code, not(containsString("a = a + 1;")));
+
 		assertThat(code, containsString("a++;"));
+		assertThat(code, not(containsString("a = a + 1;")));
 	}
 }