From 67d1b7dcd15918be38f8949b63b8f5e1a4281514 Mon Sep 17 00:00:00 2001
From: Maxime Coste <frrrwww@gmail.com>
Date: Thu, 12 Nov 2015 13:59:36 +0000
Subject: [PATCH] Faster BufferIterator::operator++/--

---
 src/buffer.hh     |  2 +-
 src/buffer.inl.hh | 17 +++++------------
 2 files changed, 6 insertions(+), 13 deletions(-)

diff --git a/src/buffer.hh b/src/buffer.hh
index 819fd8c9..72c65e5c 100644
--- a/src/buffer.hh
+++ b/src/buffer.hh
@@ -58,7 +58,7 @@ private:
     SafePtr<const Buffer> m_buffer;
     ByteCoord m_coord;
     ByteCount m_line_length;
-    LineCount m_line_count;
+    LineCount m_last_line;
 };
 
 using BufferLines = Vector<StringDataPtr, MemoryDomain::BufferContent>;
diff --git a/src/buffer.inl.hh b/src/buffer.inl.hh
index 499d63f2..887b3e09 100644
--- a/src/buffer.inl.hh
+++ b/src/buffer.inl.hh
@@ -108,7 +108,7 @@ inline ByteCoord Buffer::end_coord() const
 inline BufferIterator::BufferIterator(const Buffer& buffer, ByteCoord coord)
     : m_buffer(&buffer), m_coord(coord),
       m_line_length((*m_buffer)[m_coord.line].length()),
-      m_line_count(buffer.line_count())
+      m_last_line(buffer.line_count()-1)
 {
     kak_assert(m_buffer and m_buffer->is_valid(m_coord));
 }
@@ -193,11 +193,7 @@ inline BufferIterator& BufferIterator::operator-=(ByteCount size)
 
 inline BufferIterator& BufferIterator::operator++()
 {
-    if (m_coord.column < m_line_length - 1)
-        ++m_coord.column;
-    else if (m_coord.line == m_line_count - 1)
-        m_coord.column = m_line_length;
-    else
+    if (++m_coord.column == m_line_length and m_coord.line != m_last_line)
     {
         ++m_coord.line;
         m_coord.column = 0;
@@ -208,13 +204,10 @@ inline BufferIterator& BufferIterator::operator++()
 
 inline BufferIterator& BufferIterator::operator--()
 {
-    if (m_coord.column == 0)
+    if (m_coord.column == 0 and m_coord.line > 0)
     {
-        if (m_coord.line > 0)
-        {
-            m_line_length = m_buffer->line_storage(--m_coord.line)->length;
-            m_coord.column = m_line_length - 1;
-        }
+        m_line_length = m_buffer->line_storage(--m_coord.line)->length;
+        m_coord.column = m_line_length - 1;
     }
     else
        --m_coord.column;