fix(gui): improve smali disasm method param write (#1739)

jadx-gui/src/main/java/jadx/gui/device/debugger/smali/Smali.java

@@ -13,6 +13,8 @@ import java.util.Map.Entry;
 
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import jadx.api.ICodeInfo;
 import jadx.api.plugins.input.data.AccessFlags;
@@ -46,6 +48,7 @@ import jadx.core.dex.instructions.args.RegisterArg;
 import jadx.core.dex.nodes.ClassNode;
 import jadx.core.dex.nodes.InsnNode;
 import jadx.core.dex.nodes.MethodNode;
+import jadx.core.utils.Utils;
 import jadx.core.utils.exceptions.JadxRuntimeException;
 
 import static jadx.api.plugins.input.data.AccessFlagsScope.FIELD;
@@ -67,6 +70,7 @@ import static jadx.api.plugins.input.insns.Opcode.SPARSE_SWITCH;
 import static jadx.api.plugins.input.insns.Opcode.SPARSE_SWITCH_PAYLOAD;
 
 public class Smali {
+	private static final Logger LOG = LoggerFactory.getLogger(Smali.class);
 
 	private static SmaliInsnDecoder insnDecoder = null;
 
@@ -219,7 +223,15 @@ public class Smali {
 						writeFields(smali, clsData, fields, colWidths);
 						fields.clear();
 					}
-					writeMethod(smali, cls.getMethods().get(mthIndex[0]++), m, line);
+					try {
+						writeMethod(smali, cls.getMethods().get(mthIndex[0]++), m, line);
+					} catch (Throwable e) {
+						IMethodRef methodRef = m.getMethodRef();
+						String mthFullName = methodRef.getParentClassType() + "->" + methodRef.getName();
+						smali.setIndent(0);
+						smali.startLine("Failed to write method: " + mthFullName + "\n" + Utils.getStackTrace(e));
+						LOG.error("Failed to write smali code for method: {}", mthFullName, e);
+					}
 					line.reset();
 				});
 
@@ -451,48 +463,45 @@ public class Smali {
 		if (types.isEmpty()) {
 			return false;
 		}
-		int paramCount = 0;
-		int paramStart = 0;
-		int regNum = line.smaliMthNode.getParamRegStart();
-		if (!hasStaticFlag(mth.getAccessFlags())) {
-			line.addRegName(regNum, "p0");
-			line.smaliMthNode.setParamReg(regNum, "p0");
-			regNum += 1;
-			paramStart = 1;
-		}
+		ILocalVar[] params = new ILocalVar[codeReader.getRegistersCount()];
 		IDebugInfo dbgInfo = codeReader.getDebugInfo();
 		if (dbgInfo != null) {
 			for (ILocalVar var : dbgInfo.getLocalVars()) {
-				if (var.getRegNum() == regNum) {
-					int i = writeParamInfo(smali, line, regNum, paramStart, var.getName(), var.getType());
-					regNum += i;
-					paramStart += i;
-					paramCount++;
+				// collect only method parameters
+				if (var.getStartOffset() <= 0) {
+					params[var.getRegNum()] = var;
 				}
 			}
 		}
-		for (; paramCount < types.size(); paramCount++) {
-			int i = writeParamInfo(smali, line, regNum, paramStart, "", types.get(paramCount));
-			regNum += i;
-			paramStart += i;
-		}
-		return true;
-	}
-
-	private static int writeParamInfo(SmaliWriter smali, LineInfo line,
-			int regNum, int paramNum, String dbgInfoName, String type) {
-		smali.startLine(String.format(".param p%d, \"%s\":%s", paramNum, dbgInfoName, type));
-		String pName = "p" + paramNum;
-		line.addRegName(regNum, pName);
-		line.smaliMthNode.setParamReg(regNum, pName);
-		if (isWideType(type)) {
+		int paramStart = 0;
+		int regNum = line.smaliMthNode.getParamRegStart();
+		if (!hasStaticFlag(mth.getAccessFlags())) {
+			// add 'this' register
+			line.addRegName(regNum, "p0");
+			line.smaliMthNode.setParamReg(regNum, "p0");
 			regNum++;
-			dbgInfoName = "p" + (paramNum + 1);
-			line.addRegName(regNum, dbgInfoName);
-			line.smaliMthNode.setParamReg(regNum, dbgInfoName);
-			return 2;
+			paramStart++;
+		}
+		for (String paramType : types) {
+			String name;
+			String type;
+			ILocalVar param = params[regNum];
+			if (param != null) {
+				name = Utils.getOrElse(param.getName(), "");
+				type = Utils.getOrElse(param.getSignature(), paramType);
+			} else {
+				name = "";
+				type = paramType;
+			}
+			String varName = "p" + paramStart;
+			smali.startLine(String.format(".param %s, \"%s\" # %s", varName, name, type));
+			line.addRegName(regNum, varName);
+			line.smaliMthNode.setParamReg(regNum, varName);
+			int regSize = isWideType(paramType) ? 2 : 1;
+			regNum += regSize;
+			paramStart += regSize;
 		}
-		return 1;
+		return true;
 	}
 
 	private static int getParamStartRegNum(IMethodData mth) {

jadx-gui/src/test/java/jadx/gui/device/debugger/smali/DbgSmaliTest.java

@@ -8,6 +8,8 @@ import org.slf4j.LoggerFactory;
 import jadx.core.dex.nodes.ClassNode;
 import jadx.tests.api.SmaliTest;
 
+import static org.assertj.core.api.Assertions.assertThat;
+
 class DbgSmaliTest extends SmaliTest {
 	private static final Logger LOG = LoggerFactory.getLogger(DbgSmaliTest.class);
 
@@ -17,10 +19,20 @@ class DbgSmaliTest extends SmaliTest {
 	}
 
 	@Test
-	void test() {
+	void testSwitch() {
 		disableCompilation();
 		ClassNode cls = getClassNodeFromSmali("switch", "SwitchTest");
 		Smali disasm = Smali.disassemble(cls);
 		LOG.debug("{}", disasm.getCode());
 	}
+
+	@Test
+	void testParams() {
+		disableCompilation();
+		ClassNode cls = getClassNodeFromSmali("params", "ParamsTest");
+		Smali disasm = Smali.disassemble(cls);
+		String code = disasm.getCode();
+		LOG.debug("{}", code);
+		assertThat(code).doesNotContain("Failed to write method");
+	}
 }

jadx-gui/src/test/smali/params.smali

+.class LParamsTest;
+.super Ljava/lang/Object;
+
+.method public test(Landroid/widget/AdapterView;Landroid/view/View;IJ)V
+    .registers 10
+    .param p2, "arg1"    # Landroid/view/View;
+    .param p3, "arg2"    # I
+    .param p4, "arg3"    # J
+    .annotation system Ldalvik/annotation/Signature;
+        value = {
+            "(",
+            "Landroid/widget/AdapterView",
+            "<*>;",
+            "Landroid/view/View;",
+            "IJ)V"
+        }
+    .end annotation
+
+    .prologue
+    .line 69
+    .local p1, "arg0":Landroid/widget/AdapterView;, "Landroid/widget/AdapterView<*>;"
+    iget-object v2, p0, LParamsTest;->this$0:Ltest/ColorListActivity;
+
+    .line 72
+    iget-object v2, v2, Ltest/ColorListActivity;->mSortedColorList:[Ljava/lang/String;
+
+    .line 75
+    aget-object v0, v2, p3
+
+    .line 80
+    .local v0, "colorString":Ljava/lang/String;
+    new-instance v1, Landroid/content/Intent;
+
+    .line 83
+    iget-object v2, p0, LParamsTest;->this$0:Ltest/ColorListActivity;
+
+    .line 86
+    const-class v3, Ltest/ColorItemActivity;
+
+    .line 89
+    invoke-direct {v1, v2, v3}, Landroid/content/Intent;-><init>(Landroid/content/Context;Ljava/lang/Class;)V
+
+    .line 94
+    .local v1, "intent":Landroid/content/Intent;
+    const-string v2, "colorString"
+
+    .line 97
+    invoke-virtual {v1, v2, v0}, Landroid/content/Intent;->putExtra(Ljava/lang/String;Ljava/lang/String;)Landroid/content/Intent;
+
+    .line 101
+    iget-object v2, p0, LParamsTest;->this$0:Ltest/ColorListActivity;
+
+    .line 104
+    invoke-virtual {v2, v1}, Ltest/ColorListActivity;->startActivity(Landroid/content/Intent;)V
+
+    .line 108
+    return-void
+.end method