[PATCH 02/27] score: Add red-black tree append/prepend

[Sebastian Huber]

These functions are a faster alternative to _RBTree_Insert_inline() if
it is known that the new node is the maximum/minimum node.

Update #4531.
---
 cpukit/include/rtems/score/rbtreeimpl.h | 26 +++++++++++
 cpukit/score/src/rbtreeappend.c         | 58 +++++++++++++++++++++++++
 cpukit/score/src/rbtreeprepend.c        | 58 +++++++++++++++++++++++++
 spec/build/cpukit/librtemscpu.yml       |  2 +
 4 files changed, 144 insertions(+)
 create mode 100644 cpukit/score/src/rbtreeappend.c
 create mode 100644 cpukit/score/src/rbtreeprepend.c

diff --git a/cpukit/include/rtems/score/rbtreeimpl.h b/cpukit/include/rtems/score/rbtreeimpl.h
index 597c24d771..0867240d59 100644
--- a/cpukit/include/rtems/score/rbtreeimpl.h
+++ b/cpukit/include/rtems/score/rbtreeimpl.h
@@ -30,6 +30,32 @@ extern "C" {
  * @{
  */
 
+/**
+ * @brief Appends the node to the red-black tree.
+ *
+ * The appended node is the new maximum node of the tree.  The caller shall
+ * ensure that the appended node is indeed the maximum node with respect to the
+ * tree order.
+ *
+ * @param[in, out] the_rbtree is the red-black tree control.
+ *
+ * @param the_node[out] is the node to append.
+ */
+void _RBTree_Append( RBTree_Control *the_rbtree, RBTree_Node *the_node );
+
+/**
+ * @brief Prepends the node to the red-black tree.
+ *
+ * The prepended node is the new minimum node of the tree.  The caller shall
+ * ensure that the prepended node is indeed the minimum node with respect to the
+ * tree order.
+ *
+ * @param[in, out] the_rbtree is the red-black tree control.
+ *
+ * @param the_node[out] is the node to prepend.
+ */
+void _RBTree_Prepend( RBTree_Control *the_rbtree, RBTree_Node *the_node );
+
 /**
  * @brief Red-black tree visitor.
  *
diff --git a/cpukit/score/src/rbtreeappend.c b/cpukit/score/src/rbtreeappend.c
new file mode 100644
index 0000000000..e36f6bc805
--- /dev/null
+++ b/cpukit/score/src/rbtreeappend.c
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSScoreRBTree
+ *
+ * @brief This source file contains the implementation of
+ *   _RBTree_Append().
+ */
+
+/*
+ * Copyright (C) 2021 embedded brains GmbH (http://www.embedded-brains.de)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/score/rbtreeimpl.h>
+
+void _RBTree_Append( RBTree_Control *the_rbtree, RBTree_Node *the_node )
+{
+  RBTree_Node **link;
+  RBTree_Node  *parent;
+
+  link = _RBTree_Root_reference( the_rbtree );
+  parent = NULL;
+
+  while ( *link != NULL ) {
+    parent = *link;
+    link = _RBTree_Right_reference( parent );
+  }
+
+  _RBTree_Add_child( the_node, parent, link );
+  _RBTree_Insert_color( the_rbtree, the_node );
+}
diff --git a/cpukit/score/src/rbtreeprepend.c b/cpukit/score/src/rbtreeprepend.c
new file mode 100644
index 0000000000..f154f51d36
--- /dev/null
+++ b/cpukit/score/src/rbtreeprepend.c
@@ -0,0 +1,58 @@
+/* SPDX-License-Identifier: BSD-2-Clause */
+
+/**
+ * @file
+ *
+ * @ingroup RTEMSScoreRBTree
+ *
+ * @brief This source file contains the implementation of
+ *   _RBTree_Prepend().
+ */
+
+/*
+ * Copyright (C) 2021 embedded brains GmbH (http://www.embedded-brains.de)
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <rtems/score/rbtreeimpl.h>
+
+void _RBTree_Prepend( RBTree_Control *the_rbtree, RBTree_Node *the_node )
+{
+  RBTree_Node **link;
+  RBTree_Node  *parent;
+
+  link = _RBTree_Root_reference( the_rbtree );
+  parent = NULL;
+
+  while ( *link != NULL ) {
+    parent = *link;
+    link = _RBTree_Left_reference( parent );
+  }
+
+  _RBTree_Add_child( the_node, parent, link );
+  _RBTree_Insert_color( the_rbtree, the_node );
+}
diff --git a/spec/build/cpukit/librtemscpu.yml b/spec/build/cpukit/librtemscpu.yml
index 063917b410..819c479191 100644
--- a/spec/build/cpukit/librtemscpu.yml
+++ b/spec/build/cpukit/librtemscpu.yml
@@ -1475,6 +1475,7 @@ source:
 - cpukit/score/src/pheapwalk.c
 - cpukit/score/src/processormaskcopy.c
 - cpukit/score/src/profilingisrentryexit.c
+- cpukit/score/src/rbtreeappend.c
 - cpukit/score/src/rbtreeextract.c
 - cpukit/score/src/rbtreeinsert.c
 - cpukit/score/src/rbtreeiterate.c
@@ -1482,6 +1483,7 @@ source:
 - cpukit/score/src/rbtreemin.c
 - cpukit/score/src/rbtreenext.c
 - cpukit/score/src/rbtreepostorder.c
+- cpukit/score/src/rbtreeprepend.c
 - cpukit/score/src/rbtreeprev.c
 - cpukit/score/src/rbtreereplace.c
 - cpukit/score/src/sched.c
-- 
2.26.2