--- /dev/null	Fri Dec 21 15:00:00 2018
+++ new/usr/src/tools/smatch/src/avl.h	Fri Dec 21 15:00:00 2018
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2010 Joseph Adams <joeyadams3.14159@gmail.com>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef CCAN_AVL_H
+#define CCAN_AVL_H
+
+#include <stdbool.h>
+#include <stddef.h>
+
+struct sm_state;
+
+typedef struct AvlNode       AvlNode;
+typedef struct AvlIter       AvlIter;
+
+struct stree {
+	AvlNode    *root;
+	struct stree *base_stree;
+	char *has_states;
+	size_t      count;
+	int stree_id;
+	int references;
+};
+
+void free_stree(struct stree **avl);
+	/* Free an stree tree. */
+
+struct sm_state *avl_lookup(const struct stree *avl, const struct sm_state *sm);
+	/* O(log n). Lookup a sm.  Return NULL if the sm is not present. */
+
+#define avl_member(avl, sm) (!!avl_lookup_node(avl, sm))
+	/* O(log n). See if a sm is present. */
+
+size_t stree_count(const struct stree *avl);
+	/* O(1). Return the number of elements in the tree. */
+
+bool avl_insert(struct stree **avl, const struct sm_state *sm);
+	/*
+	 * O(log n). Insert an sm or replace it if already present.
+	 *
+	 * Return false if the insertion replaced an existing sm.
+	 */
+
+bool avl_remove(struct stree **avl, const struct sm_state *sm);
+	/*
+	 * O(log n). Remove an sm (if present).
+	 *
+	 * Return true if it was removed.
+	 */
+
+bool avl_check_invariants(struct stree *avl);
+	/* For testing purposes.  This function will always return true :-) */
+
+
+/************************* Traversal *************************/
+
+#define avl_foreach(iter, avl)         avl_traverse(iter, avl, FORWARD)
+	/*
+	 * O(n). Traverse an stree tree in order.
+	 *
+	 * Example:
+	 *
+	 * AvlIter i;
+	 *
+	 * avl_foreach(i, avl)
+	 *     printf("%s -> %s\n", i.sm->name, i.sm->state->name);
+	 */
+
+#define FOR_EACH_SM(avl, _sm) {			\
+	AvlIter _i;				\
+	avl_foreach(_i, avl) {			\
+		_sm = _i.sm;
+
+#define END_FOR_EACH_SM(_sm) }}
+
+#define FOR_EACH_MY_SM(_owner, avl, _sm) {	\
+	AvlIter _i;				\
+	avl_foreach(_i, avl) {			\
+		_sm = _i.sm;			\
+		if (_sm->owner != _owner)	\
+			continue;		\
+
+#define avl_foreach_reverse(iter, avl) avl_traverse(iter, avl, BACKWARD)
+	/* O(n). Traverse an stree tree in reverse order. */
+
+typedef enum AvlDirection {FORWARD = 0, BACKWARD = 1} AvlDirection;
+
+struct AvlIter {
+	struct sm_state *sm;
+	AvlNode      *node;
+
+	/* private */
+	AvlNode      *stack[100];
+	int           stack_index;
+	AvlDirection  direction;
+};
+
+void avl_iter_begin(AvlIter *iter, struct stree *avl, AvlDirection dir);
+void avl_iter_next(AvlIter *iter);
+#define avl_traverse(iter, avl, direction)        \
+	for (avl_iter_begin(&(iter), avl, direction); \
+	     (iter).node != NULL;                     \
+	     avl_iter_next(&iter))
+
+
+/***************** Internal data structures ******************/
+
+struct AvlNode {
+	const struct sm_state *sm;
+
+	AvlNode    *lr[2];
+	int         balance; /* -1, 0, or 1 */
+};
+
+AvlNode *avl_lookup_node(const struct stree *avl, const struct sm_state *sm);
+	/* O(log n). Lookup an stree node by sm.  Return NULL if not present. */
+
+struct stree *clone_stree(struct stree *orig);
+
+void set_stree_id(struct stree **stree, int id);
+int get_stree_id(struct stree *stree);
+
+#endif
