From c1efa5e66158d6dc816523a908a030731a0ec330 Mon Sep 17 00:00:00 2001
From: Igor Sysoev <igor@sysoev.ru>
Date: Fri, 20 Jan 2017 16:10:48 +0300
Subject: [PATCH] A small rbtree insert fixup optimization.
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Thanks to 洪志道 (Hong Zhi Dao).
---
 nxt/nxt_rbtree.c | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/nxt/nxt_rbtree.c b/nxt/nxt_rbtree.c
index 24cb4e6f..852317d4 100644
--- a/nxt/nxt_rbtree.c
+++ b/nxt/nxt_rbtree.c
@@ -135,8 +135,12 @@ nxt_rbtree_insert_fixup(nxt_rbtree_node_t *node)
                 grandparent = parent->parent;
                 grandparent->color = NXT_RBTREE_RED;
                 nxt_rbtree_right_rotate(grandparent);
-
-                continue;
+                /*
+                 * nxt_rbtree_right_rotate() does not change node->parent
+                 * color which is now black, so testing color is not required
+                 * to return from function.
+                 */
+                return;
             }
 
         } else {
@@ -156,7 +160,8 @@ nxt_rbtree_insert_fixup(nxt_rbtree_node_t *node)
                 grandparent->color = NXT_RBTREE_RED;
                 nxt_rbtree_left_rotate(grandparent);
 
-                continue;
+                /* See the comment in the symmetric branch above. */
+                return;
             }
         }
 
-- 
2.47.3