From 2a0af0f9bd33a4031ddc15c4be57d377dd849ae5 Mon Sep 17 00:00:00 2001
From: Francesco Cozzuto <heibyob@gmail.com>
Date: Wed, 8 Dec 2021 18:15:59 +0100
Subject: [PATCH] minor buffer object optimization

---
 samples/bytetree.noja  | 87 ++++++++++++++++++++++++++++++++++++++++++
 samples/tree.noja      |  2 +-
 src/objects/o_buffer.c | 18 ++++++---
 3 files changed, 101 insertions(+), 6 deletions(-)
 create mode 100644 samples/bytetree.noja

diff --git a/samples/bytetree.noja b/samples/bytetree.noja
new file mode 100644
index 0000000..3880317
--- /dev/null
+++ b/samples/bytetree.noja
@@ -0,0 +1,87 @@
+
+fun newBytetree(leaf_size)
+{
+	if leaf_size == none:
+		leaf_size = 64;
+
+	return { root: none, size: 0, leaf_size: leaf_size };
+}
+
+fun makeBufferIntoTree(buffer)
+{
+	nleafs = 1.0 * count(data) / tree.leaf_size;
+	assert(type(nleafs) == type(0.0));
+
+	print('nleafs = ', nleafs, '\n');
+
+	leafs = [];
+
+	# Make a big buffer and then split it
+	# into `nleafs` slices, then store the
+	# slices into the `leafs` array.
+	leafs_buffer = newBuffer(nleafs * tree.leaf_size);
+	while count(leafs) < nleafs:
+		leafs[count(leafs)] = 
+			sliceBuffer(leafs_buffer, i * tree.leaf_size, tree.leaf_size);
+	
+	nodes = leafs;
+	while count(nodes) > 1:
+		{
+			temp = [];
+
+			npairs = count(nodes) / 2;
+
+			while count(temp) < npairs:
+				temp[count(temp)] = {
+					left : nodes[count(temp) * 2],
+					right: nodes[count(temp) * 2 + 1]
+				};
+			
+			if npairs * 2 < count(nodes):
+				# There's an extra node we
+				# need to handle.
+				temp[count(temp)-1] = {
+					left: temp[count(temp)-1],
+					right: nodes[count(nodes)-1]
+				};
+		
+			nodes = temp;
+		}
+
+	assert(count(nodes) == 1);
+
+	return nodes[0];
+}
+
+fun insertIntoBytetree(tree, data, index)
+{
+	if index == none:
+		index = tree.size;
+
+	subtree = makeBufferIntoTree(data);
+
+	if tree.root == none:
+		{
+			tree.root = subtree;
+			return;
+		}
+
+	# Now find where to store this
+	# subtree.
+	current = tree.root;
+
+
+	rel_index = index;
+	while type(current) == type({}):
+		{
+			if rel_index < current.left_size:
+				current = current.left;
+			else
+				{
+					rel_index = rel_index - current.left_size;
+					current = current.right;
+				}
+		}
+
+	
+}
\ No newline at end of file
diff --git a/samples/tree.noja b/samples/tree.noja
index 8210df9..c18094c 100644
--- a/samples/tree.noja
+++ b/samples/tree.noja
@@ -36,7 +36,7 @@ fun locate(tree, index, path)
 	
 	path[count(path)] = cursor;
 
-	while cursor.is_leaf == false:
+	while not cursor.is_leaf:
 		{
 			if rindex < _count(cursor.left):
 				cursor = cursor.left;
diff --git a/src/objects/o_buffer.c b/src/objects/o_buffer.c
index ece8001..92f4302 100644
--- a/src/objects/o_buffer.c
+++ b/src/objects/o_buffer.c
@@ -111,15 +111,18 @@ Object *Object_SliceBuffer(Object *buffer, int offset, int length, Heap *heap, E
 			return NULL;
 		}
 
-	BufferSliceObject *slice = (BufferSliceObject*) Heap_Malloc(heap, &t_buffer_slice, error);
-
-	if(slice == NULL)
-		return NULL;
-
 	if(buffer->type == &t_buffer)
 		{
 			BufferObject *original = (BufferObject*) buffer;
 
+			if(offset == 0 && length == original->size)
+				return buffer;
+
+			BufferSliceObject *slice = (BufferSliceObject*) Heap_Malloc(heap, &t_buffer_slice, error);
+
+			if(slice == NULL)
+				return NULL;
+
 			if(offset < 0 || offset >= original->size)
 				{
 					Error_Report(error, 0, "offset out of range");
@@ -146,6 +149,11 @@ Object *Object_SliceBuffer(Object *buffer, int offset, int length, Heap *heap, E
 		{
 			assert(buffer->type == &t_buffer_slice);
 
+			BufferSliceObject *slice = (BufferSliceObject*) Heap_Malloc(heap, &t_buffer_slice, error);
+
+			if(slice == NULL)
+				return NULL;
+
 			BufferSliceObject *original = (BufferSliceObject*) buffer;
 
 			if(offset < 0 || offset >= original->length)