Xref for function variables in disassembly view (#2297)

src/core/Cutter.cpp

@@ -28,6 +28,7 @@ Q_GLOBAL_STATIC(CutterCore, uniqueInstance)
 
 namespace RJsonKey {
     R_JSON_KEY(addr);
+    R_JSON_KEY(addrs);
     R_JSON_KEY(addr_end);
     R_JSON_KEY(arrow);
     R_JSON_KEY(baddr);
@@ -476,6 +477,18 @@ QJsonDocument CutterCore::cmdj(const char *str)
     return doc;
 }
 
+QJsonDocument CutterCore::cmdjAt(const char *str, RVA address)
+{
+    QJsonDocument res;
+    RVA oldOffset = getOffset();
+    seekSilent(address);
+
+    res = cmdj(str);
+
+    seekSilent(oldOffset);
+    return res;
+}
+
 QString CutterCore::cmdTask(const QString &str)
 {
     R2Task task(str);
@@ -3459,6 +3472,37 @@ BlockStatistics CutterCore::getBlockStatistics(unsigned int blocksCount)
     return blockStats;
 }
 
+QList<XrefDescription> CutterCore::getXRefsForVariable(QString variableName, bool findWrites, RVA offset)
+{
+    QList<XrefDescription> xrefList = QList<XrefDescription>();
+    QJsonArray xrefsArray;
+    if (findWrites) {
+        xrefsArray = cmdjAt("afvWj", offset).array();
+    } else {
+        xrefsArray = cmdjAt("afvRj", offset).array();
+    }
+    for (const QJsonValue &value : xrefsArray) {
+        QJsonObject xrefObject = value.toObject();
+        QString name = xrefObject[RJsonKey::name].toString();
+        if (name == variableName) {
+            QJsonArray addressArray = xrefObject[RJsonKey::addrs].toArray();
+            for (const QJsonValue &address : addressArray) {
+                XrefDescription xref;
+                RVA addr = address.toVariant().toULongLong();
+                xref.from = addr;
+                xref.to = addr;
+                if (findWrites) {
+                    xref.from_str = RAddressString(addr);
+                } else {
+                    xref.to_str = RAddressString(addr);
+                }
+                xrefList << xref;
+            }
+        }
+    }
+    return xrefList;
+}
+
 QList<XrefDescription> CutterCore::getXRefs(RVA addr, bool to, bool whole_function,
                                             const QString &filterType)
 {

src/core/Cutter.h

@@ -109,6 +109,7 @@ public:
     
     QJsonDocument cmdj(const char *str);
     QJsonDocument cmdj(const QString &str) { return cmdj(str.toUtf8().constData()); }
+    QJsonDocument cmdjAt(const char *str, RVA address);
     QStringList cmdList(const char *str) { return cmd(str).split(QLatin1Char('\n'), CUTTER_QT_SKIP_EMPTY_PARTS); }
     QStringList cmdList(const QString &str) { return cmdList(str.toUtf8().constData()); }
     QString cmdTask(const QString &str);
@@ -567,7 +568,17 @@ public:
     QList<QJsonObject> getRegisterRefs(int depth = 6);
     QVector<RegisterRefValueDescription> getRegisterRefValues();
     QList<VariableDescription> getVariables(RVA at);
-
+    /**
+     * @brief Fetches all the writes or reads to the specified local variable 'variableName'
+     * in the function in which the specified offset is a part of.
+     * @param variableName Name of the local variable.
+     * @param findWrites If this is true, then locations at which modification happen to the specified
+     * local variable is fetched. Else, the locations at which the local is variable is read is fetched.
+     * @param offset An offset in the function in which the specified local variable exist.
+     * @return A list of XrefDescriptions that contains details of all the writes or reads that happen to the
+     * variable 'variableName'.
+     */
+    QList<XrefDescription> getXRefsForVariable(QString variableName, bool findWrites, RVA offset);
     QList<XrefDescription> getXRefs(RVA addr, bool to, bool whole_function,
                                     const QString &filterType = QString());
 

src/dialogs/XrefsDialog.cpp

@@ -138,12 +138,14 @@ void XrefsDialog::updateLabels(QString name)
     ui->label_xFrom->setText(tr("X-Refs from %1:").arg(name));
 }
 
+void XrefsDialog::updateLabelsForVariables(QString name)
+{
+    ui->label_xTo->setText(tr("Writes to %1").arg(name));
+    ui->label_xFrom->setText(tr("Reads from %1").arg(name));
+}
+
 void XrefsDialog::fillRefsForAddress(RVA addr, QString name, bool whole_function)
 {
-    TempConfig tempConfig;
-    tempConfig.set("scr.html", false);
-    tempConfig.set("scr.color", COLOR_MODE_DISABLED);
-
     setWindowTitle(tr("X-Refs for %1").arg(name));
     updateLabels(name);
 
@@ -160,6 +162,27 @@ void XrefsDialog::fillRefsForAddress(RVA addr, QString name, bool whole_function
     }
 }
 
+void XrefsDialog::fillRefsForVariable(QString nameOfVariable, RVA offset)
+{
+    setWindowTitle(tr("X-Refs for %1").arg(nameOfVariable));
+    updateLabelsForVariables(nameOfVariable);
+
+    // Initialize Model
+    toModel.readForVariable(nameOfVariable, true, offset);
+    fromModel.readForVariable(nameOfVariable, false, offset);
+    // Hide irrelevant column 1: which shows type
+    ui->fromTreeWidget->hideColumn(XrefModel::Columns::TYPE);
+    ui->toTreeWidget->hideColumn(XrefModel::Columns::TYPE);
+    // Adjust columns to content
+    qhelpers::adjustColumns(ui->fromTreeWidget, fromModel.columnCount(), 0);
+    qhelpers::adjustColumns(ui->toTreeWidget, toModel.columnCount(), 0);
+
+    // Automatically select the first line
+    if (!qhelpers::selectFirstItem(ui->toTreeWidget)) {
+        qhelpers::selectFirstItem(ui->fromTreeWidget);
+    }
+}
+
 QString XrefModel::xrefTypeString(const QString &type)
 {
     if (type == "CODE") {
@@ -188,6 +211,14 @@ void XrefModel::readForOffset(RVA offset, bool to, bool whole_function)
     endResetModel();
 }
 
+void XrefModel::readForVariable(QString nameOfVariable, bool write, RVA offset)
+{
+    beginResetModel();
+    this->to = write;
+    xrefs = Core()->getXRefsForVariable(nameOfVariable, write, offset);
+    endResetModel();
+}
+
 int XrefModel::rowCount(const QModelIndex &parent) const
 {
     Q_UNUSED(parent)

src/dialogs/XrefsDialog.h

@@ -19,7 +19,7 @@ public:
 
     XrefModel(QObject *parent = nullptr);
     void readForOffset(RVA offset, bool to, bool whole_function);
-
+    void readForVariable(QString nameOfVariable, bool write, RVA offset);
     int rowCount(const QModelIndex &parent = QModelIndex()) const override;
     int columnCount(const QModelIndex &parent = QModelIndex()) const override;
 
@@ -48,6 +48,13 @@ public:
     ~XrefsDialog();
 
     void fillRefsForAddress(RVA addr, QString name, bool whole_function);
+    /**
+     * @brief Initializes toModel and fromModel with the details about the references to the specified
+     * local variable 'nameOfVariable'.
+     * @param nameOfVarible Name of the local variable for which the references are being initialized.
+     * @param offset An offset in the function in which the specified local variable exist.
+     */
+    void fillRefsForVariable(QString nameOfVariable, RVA offset);
 
 private slots:
     QString normalizeAddr(const QString &addr) const;
@@ -69,6 +76,7 @@ private:
     std::unique_ptr<Ui::XrefsDialog> ui;
 
     void updateLabels(QString name);
+    void updateLabelsForVariables(QString name);
     void updatePreview(RVA addr);
 };
 

src/menus/DisassemblyContextMenu.cpp

@@ -39,6 +39,7 @@ DisassemblyContextMenu::DisassemblyContextMenu(QWidget *parent, MainWindow *main
         actionRenameUsedHere(this),
         actionSetFunctionVarTypes(this),
         actionXRefs(this),
+        actionXRefsForVariables(this),
         actionDisplayOptions(this),
         actionDeleteComment(this),
         actionDeleteFlag(this),
@@ -142,6 +143,10 @@ DisassemblyContextMenu::DisassemblyContextMenu(QWidget *parent, MainWindow *main
                SLOT(on_actionXRefs_triggered()), getXRefSequence());
     addAction(&actionXRefs);
 
+    initAction(&actionXRefsForVariables, tr("X-Refs for local variables"),
+                SLOT(on_actionXRefsForVariables_triggered()), QKeySequence({Qt::SHIFT + Qt::Key_X}));
+    addAction(&actionXRefsForVariables);
+
     initAction(&actionDisplayOptions, tr("Show Options"),
                SLOT(on_actionDisplayOptions_triggered()), getDisplayOptionsSequence());
 
@@ -165,6 +170,8 @@ DisassemblyContextMenu::DisassemblyContextMenu(QWidget *parent, MainWindow *main
 
     connect(this, &DisassemblyContextMenu::aboutToShow,
             this, &DisassemblyContextMenu::aboutToShowSlot);
+    connect(this, &DisassemblyContextMenu::aboutToHide,
+            this, &DisassemblyContextMenu::aboutToHideSlot);
 }
 
 DisassemblyContextMenu::~DisassemblyContextMenu()
@@ -559,6 +566,17 @@ void DisassemblyContextMenu::aboutToShowSlot()
             pluginAction->setData(QVariant::fromValue(offset));
         }
     }
+
+    bool isLocalVar = isHighlightedWordLocalVar();
+    actionXRefsForVariables.setVisible(isLocalVar);
+    if (isLocalVar) {
+        actionXRefsForVariables.setText(tr("X-Refs for %1").arg(curHighlightedWord));
+    }
+}
+
+void DisassemblyContextMenu::aboutToHideSlot()
+{
+    actionXRefsForVariables.setVisible(true);
 }
 
 QKeySequence DisassemblyContextMenu::getCopySequence() const
@@ -880,6 +898,15 @@ void DisassemblyContextMenu::on_actionXRefs_triggered()
     dialog.exec();
 }
 
+void DisassemblyContextMenu::on_actionXRefsForVariables_triggered()
+{
+    if (isHighlightedWordLocalVar()) {
+        XrefsDialog dialog(mainWindow, nullptr);
+        dialog.fillRefsForVariable(curHighlightedWord, offset);
+        dialog.exec();
+    }
+}
+
 void DisassemblyContextMenu::on_actionDisplayOptions_triggered()
 {
     PreferencesDialog dialog(this->window());
@@ -1081,3 +1108,14 @@ void DisassemblyContextMenu::initAction(QAction *action, QString name,
     action->setShortcuts(keySequenceList);
     action->setShortcutContext(Qt::WidgetWithChildrenShortcut);
 }
+
+bool DisassemblyContextMenu::isHighlightedWordLocalVar()
+{
+    QList<VariableDescription> variables = Core()->getVariables(offset);
+    for (const VariableDescription &var : variables) {
+        if (var.name == curHighlightedWord) {
+            return true;
+        }
+    }
+    return false;
+}

src/menus/DisassemblyContextMenu.h

@@ -29,6 +29,7 @@ public slots:
 
 private slots:
     void aboutToShowSlot();
+    void aboutToHideSlot();
 
     void on_actionEditFunction_triggered();
     void on_actionEditInstruction_triggered();
@@ -46,6 +47,7 @@ private slots:
     void on_actionRenameUsedHere_triggered();
     void on_actionSetFunctionVarTypes_triggered();
     void on_actionXRefs_triggered();
+    void on_actionXRefsForVariables_triggered();
     void on_actionDisplayOptions_triggered();
 
     void on_actionDeleteComment_triggered();
@@ -131,6 +133,7 @@ private:
     QAction actionRenameUsedHere;
     QAction actionSetFunctionVarTypes;
     QAction actionXRefs;
+    QAction actionXRefsForVariables;
     QAction actionDisplayOptions;
 
     QAction actionDeleteComment;
@@ -203,6 +206,13 @@ private:
     void addBreakpointMenu();
     void addDebugMenu();
 
+    /**
+     * @brief Checks if the currently highlighted word in the disassembly widget
+     * is a local variable or function paramter.
+     * @return Return true if the highlighted word is the name of a local variable or function parameter,
+     * return false otherwise.
+     */
+    bool isHighlightedWordLocalVar();
     struct ThingUsedHere {
         QString name;
         RVA offset;