Bug 548982 - [GTK] Optimize bulk inserting items to Tree

Change-Id: I1b6c19d043cc42ac244926129eef2ba71ef174ad
Signed-off-by: Alexandr Miloslavskiy <alexandr.miloslavskiy@syntevo.com>

5 files changed, 57 insertions, 10 deletions

diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
index dfab9f7cd9..e0326b8506 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os.c
@@ -11008,6 +11008,16 @@ fail:
 }
 #endif
 
+#ifndef NO__1gtk_1tree_1store_1prepend
+JNIEXPORT void JNICALL GTK_NATIVE(_1gtk_1tree_1store_1prepend)
+	(JNIEnv *env, jclass that, jlong arg0, jlong arg1, jlong arg2)
+{
+	GTK_NATIVE_ENTER(env, that, _1gtk_1tree_1store_1prepend_FUNC);
+	gtk_tree_store_prepend((GtkTreeStore *)arg0, (GtkTreeIter *)arg1, (GtkTreeIter *)arg2);
+	GTK_NATIVE_EXIT(env, that, _1gtk_1tree_1store_1prepend_FUNC);
+}
+#endif
+
 #ifndef NO__1gtk_1tree_1store_1remove
 JNIEXPORT void JNICALL GTK_NATIVE(_1gtk_1tree_1store_1remove)
 	(JNIEnv *env, jclass that, jlong arg0, jlong arg1)
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
index 8589c73125..3512668735 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.c
@@ -875,6 +875,7 @@ char * GTK_nativeFunctionNames[] = {
 	"_1gtk_1tree_1store_1clear",
 	"_1gtk_1tree_1store_1insert",
 	"_1gtk_1tree_1store_1newv",
+	"_1gtk_1tree_1store_1prepend",
 	"_1gtk_1tree_1store_1remove",
 	"_1gtk_1tree_1store_1set__JJIII",
 	"_1gtk_1tree_1store_1set__JJIJI",
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
index 73994032b7..642bc88848 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/library/os_stats.h
@@ -873,6 +873,7 @@ typedef enum {
 	_1gtk_1tree_1store_1clear_FUNC,
 	_1gtk_1tree_1store_1insert_FUNC,
 	_1gtk_1tree_1store_1newv_FUNC,
+	_1gtk_1tree_1store_1prepend_FUNC,
 	_1gtk_1tree_1store_1remove_FUNC,
 	_1gtk_1tree_1store_1set__JJIII_FUNC,
 	_1gtk_1tree_1store_1set__JJIJI_FUNC,
diff --git a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
index eae8f49f1e..5b811b8691 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT PI/gtk/org/eclipse/swt/internal/gtk/GTK.java
@@ -7565,6 +7565,20 @@ public class GTK extends OS {
 	/**
 	 * @param store cast=(GtkTreeStore *)
 	 * @param iter cast=(GtkTreeIter *)
+	 * @param parent cast=(GtkTreeIter *)
+	 */
+	public static final native void _gtk_tree_store_prepend(long store, long iter, long parent);
+	public static final void gtk_tree_store_prepend(long store, long iter, long parent) {
+		lock.lock();
+		try {
+			_gtk_tree_store_prepend(store, iter, parent);
+		} finally {
+			lock.unlock();
+		}
+	}
+	/**
+	 * @param store cast=(GtkTreeStore *)
+	 * @param iter cast=(GtkTreeIter *)
 	 */
 	public static final native void _gtk_tree_store_remove(long store, long iter);
 	public static final void gtk_tree_store_remove(long store, long iter) {
diff --git a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java
index 0ef25d72fa..77975e12c4 100644
--- a/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java
+++ b/bundles/org.eclipse.swt/Eclipse SWT/gtk/org/eclipse/swt/widgets/Tree.java
@@ -890,21 +890,42 @@ void createItem (TreeColumn column, int index) {
 	}
 }
 
+/*
+ * NOTE: the fastest way to bulk-insert items is to insert every item
+ * at index 0 (insert in reverse to preserve order).
+ */
 void createItem (TreeItem item, long parentIter, int index) {
-	int count = GTK.gtk_tree_model_iter_n_children (modelHandle, parentIter);
-	if (index == -1) index = count;
-	if (!(0 <= index && index <= count)) error (SWT.ERROR_INVALID_RANGE);
-	item.handle = OS.g_malloc (GTK.GtkTreeIter_sizeof ());
-	if (item.handle == 0) error(SWT.ERROR_NO_HANDLES);
 	/*
-	* Feature in GTK.  It is much faster to append to a tree store
-	* than to insert at the end using gtk_tree_store_insert().
-	*/
-	if (index == count) {
+	 * Try to achieve maximum possible performance in bulk insert scenarios.
+	 * Even a single call to 'gtk_tree_model_iter_n_children' already
+	 * reduces performance 3x, so try to avoid any unneeded API calls.
+	 */
+	if (index == 0) {
+		item.handle = OS.g_malloc (GTK.GtkTreeIter_sizeof ());
+		if (item.handle == 0) error(SWT.ERROR_NO_HANDLES);
+		GTK.gtk_tree_store_prepend (modelHandle, item.handle, parentIter);
+	} else if (index == -1) {
+		item.handle = OS.g_malloc (GTK.GtkTreeIter_sizeof ());
+		if (item.handle == 0) error(SWT.ERROR_NO_HANDLES);
 		GTK.gtk_tree_store_append (modelHandle, item.handle, parentIter);
 	} else {
-		GTK.gtk_tree_store_insert (modelHandle, item.handle, parentIter, index);
+		int count = GTK.gtk_tree_model_iter_n_children (modelHandle, parentIter);
+		if (!(0 <= index && index <= count)) error (SWT.ERROR_INVALID_RANGE);
+
+		item.handle = OS.g_malloc (GTK.GtkTreeIter_sizeof ());
+		if (item.handle == 0) error(SWT.ERROR_NO_HANDLES);
+
+		/*
+		 * Feature in GTK.  It is much faster to append to a tree store
+		 * than to insert at the end using gtk_tree_store_insert().
+		 */
+		if (index == count) {
+			GTK.gtk_tree_store_append (modelHandle, item.handle, parentIter);
+		} else {
+			GTK.gtk_tree_store_insert (modelHandle, item.handle, parentIter, index);
+		}
 	}
+
 	int id = getId (item.handle, false);
 	items [id] = item;
 	modelChanged = true;