Allow clicking on branch arrows to scroll target into view

encounter · encounter · Dec 21, 2025 · Dec 18, 2025 · Dec 18, 2025 · Dec 18, 2025
commit f139e7425d1b20c077516d7988395ae1b23d73db
diff --git a/objdiff-cli/src/views/function_diff.rs b/objdiff-cli/src/views/function_diff.rs
@@ -539,6 +539,7 @@ impl FunctionDiffUi {
                     DiffText::Opcode(mnemonic, _op) => format!("{mnemonic} "),
                     DiffText::Argument(arg) => arg.to_string(),
                     DiffText::BranchDest(addr) => format!("{addr:x}"),
+                    DiffText::BranchArrow(_) => " ~> ".to_string(),
                     DiffText::Symbol(sym) => {
                         sym.demangled_name.as_ref().unwrap_or(&sym.name).clone()
                     }

diff --git a/objdiff-core/src/diff/display.rs b/objdiff-core/src/diff/display.rs
@@ -37,6 +37,8 @@ pub enum DiffText<'a> {
     Argument(InstructionArgValue<'a>),
     /// Branch destination
     BranchDest(u64),
+    /// Branch source/destination arrow, scrolls to a specific row when clicked
+    BranchArrow(u32),
     /// Symbol name
     Symbol(&'a Symbol),
     /// Relocation addend
@@ -185,7 +187,13 @@ pub fn display_row(
         pad_to: 5,
     })?;
     if let Some(branch) = &ins_row.branch_from {
-        cb(DiffTextSegment::basic(" ~> ", DiffTextColor::Rotating(branch.branch_idx as u8)))?;
+        // Pick the first branch source if there are multiple.
+        let ins_idx = branch.ins_idx[0];
+        cb(DiffTextSegment {
+            text: DiffText::BranchArrow(ins_idx),
+            color: DiffTextColor::Rotating(branch.branch_idx as u8),
+            pad_to: 0,
+        })?;
     } else {
         cb(DiffTextSegment::spacing(4))?;
     }
@@ -307,7 +315,11 @@ pub fn display_row(
         cb(DiffTextSegment::basic(">", base_color))?;
     }
     if let Some(branch) = &ins_row.branch_to {
-        cb(DiffTextSegment::basic(" ~>", DiffTextColor::Rotating(branch.branch_idx as u8)))?;
+        cb(DiffTextSegment {
+            text: DiffText::BranchArrow(branch.ins_idx),
+            color: DiffTextColor::Rotating(branch.branch_idx as u8),
+            pad_to: 0,
+        })?;
     }
     cb(EOL_SEGMENT)?;
     Ok(())

diff --git a/objdiff-gui/src/views/column_layout.rs b/objdiff-gui/src/views/column_layout.rs
@@ -34,19 +34,23 @@ pub fn render_table(
     num_columns: usize,
     row_height: f32,
     total_rows: usize,
+    scroll_to_row: Option<usize>,
     mut add_contents: impl FnMut(&mut TableRow, usize),
 ) {
     ui.style_mut().interaction.selectable_labels = false;
     let column_width = available_width / num_columns as f32;
     let available_height = ui.available_height();
-    let table = TableBuilder::new(ui)
+    let mut table = TableBuilder::new(ui)
         .striped(false)
         .cell_layout(Layout::left_to_right(Align::Min))
         .columns(Column::exact(column_width).clip(true), num_columns)
         .resizable(false)
         .auto_shrink([false, false])
         .min_scrolled_height(available_height)
         .sense(Sense::click());
+    if let Some(row) = scroll_to_row {
+        table = table.scroll_to_row(row, Some(Align::Center));
+    }
     table.body(|body| {
         body.rows(row_height, total_rows, |mut row| {
             row.set_hovered(false); // Disable hover effect

diff --git a/objdiff-gui/src/views/diff.rs b/objdiff-gui/src/views/diff.rs
@@ -93,6 +93,7 @@ fn get_asm_text(
                     InstructionArgValue::Opaque(v) => v.into_owned(),
                 },
                 DiffText::BranchDest(addr) => format!("{addr:x}"),
+                DiffText::BranchArrow(_) => " ~> ".to_string(),
                 DiffText::Symbol(sym) => sym.demangled_name.as_ref().unwrap_or(&sym.name).clone(),
                 DiffText::Addend(addend) => match addend.cmp(&0i64) {
                     Ordering::Greater => format!("+{addend:#x}"),
@@ -498,6 +499,7 @@ pub fn diff_view_ui(
                 2,
                 appearance.code_font.size,
                 instructions_len,
+                state.function_state.scroll_to_row,
                 |row, column| {
                     if column == 0 {
                         if let Some(action) = asm_col_ui(
@@ -560,6 +562,7 @@ pub fn diff_view_ui(
                 2,
                 appearance.code_font.size,
                 total_rows,
+                None,
                 |row, column| {
                     let i = row.index();
                     let row_offset = i as u64 * BYTES_PER_ROW as u64;
@@ -690,6 +693,7 @@ fn diff_col_ui(
                     1,
                     appearance.code_font.size,
                     total_rows,
+                    None,
                     |row, _column| {
                         let i = row.index();
                         let row_offset = i as u64 * BYTES_PER_ROW as u64;
@@ -713,6 +717,7 @@ fn diff_col_ui(
                     1,
                     appearance.code_font.size,
                     symbol_diff.instruction_rows.len(),
+                    state.function_state.scroll_to_row,
                     |row, column| {
                         if let Some(action) = asm_col_ui(
                             row,

diff --git a/objdiff-gui/src/views/function_diff.rs b/objdiff-gui/src/views/function_diff.rs
@@ -24,6 +24,7 @@ use crate::views::{
 pub struct FunctionViewState {
     left_highlight: HighlightKind,
     right_highlight: HighlightKind,
+    pub scroll_to_row: Option<usize>,
 }
 
 impl FunctionViewState {
@@ -143,6 +144,7 @@ fn diff_text_ui(
     response_cb: impl Fn(Response) -> Response,
 ) -> Option<DiffViewAction> {
     let highlight_kind = HighlightKind::from(&segment.text);
+    let mut branch_to_ins_idx = None;
     let label_text = match segment.text {
         DiffText::Basic(text) => text.to_string(),
         DiffText::Line(num) => format!("{num} "),
@@ -154,6 +156,10 @@ fn diff_text_ui(
             InstructionArgValue::Opaque(v) => v.into_owned(),
         },
         DiffText::BranchDest(addr) => format!("{addr:x}"),
+        DiffText::BranchArrow(ins_idx) => {
+            branch_to_ins_idx = Some(ins_idx);
+            " ~> ".to_string()
+        }
         DiffText::Symbol(sym) => sym.demangled_name.as_ref().unwrap_or(&sym.name).clone(),
         DiffText::Addend(addend) => match addend.cmp(&0i64) {
             Ordering::Greater => format!("+{addend:#x}"),
@@ -191,7 +197,11 @@ fn diff_text_ui(
     response = response_cb(response);
     let mut ret = None;
     if response.clicked() {
-        ret = Some(DiffViewAction::SetDiffHighlight(column, highlight_kind));
+        if let Some(ins_idx) = branch_to_ins_idx {
+            ret = Some(DiffViewAction::ScrollToRow(ins_idx as usize));
+        } else {
+            ret = Some(DiffViewAction::SetDiffHighlight(column, highlight_kind));
+        }
     }
     if len < segment.pad_to as usize {
         ui.add_space((segment.pad_to as usize - len) as f32 * space_width);

diff --git a/objdiff-gui/src/views/symbol_diff.rs b/objdiff-gui/src/views/symbol_diff.rs
@@ -81,6 +81,8 @@ pub enum DiffViewAction {
     SetShowMappedSymbols(bool),
     /// Set the show_data_flow flag
     SetShowDataFlow(bool),
+    // Scrolls a row of the function view table into view.
+    ScrollToRow(usize),
 }
 
 #[derive(Debug, Clone, Default, Eq, PartialEq)]
@@ -193,8 +195,9 @@ impl DiffViewState {
             ctx.open_url(OpenUrl::new_tab(result.scratch_url));
         }
 
-        // Clear the autoscroll flag so that it doesn't scroll continuously.
+        // Clear the scroll flags to prevent it from scrolling continuously.
         self.symbol_state.autoscroll_to_highlighted_symbols = false;
+        self.function_state.scroll_to_row = None;
 
         let Some(action) = action else {
             return;
@@ -362,6 +365,9 @@ impl DiffViewState {
                 };
                 state.config.diff_obj_config.show_data_flow = value;
             }
+            DiffViewAction::ScrollToRow(row) => {
+                self.function_state.scroll_to_row = Some(row);
+            }
         }
     }