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-rw-r--r--gnu/egcs/libiberty/splay-tree.c370
1 files changed, 0 insertions, 370 deletions
diff --git a/gnu/egcs/libiberty/splay-tree.c b/gnu/egcs/libiberty/splay-tree.c
deleted file mode 100644
index 22ea07d84ad..00000000000
--- a/gnu/egcs/libiberty/splay-tree.c
+++ /dev/null
@@ -1,370 +0,0 @@
-/* A splay-tree datatype.
- Copyright (C) 1998, 1999 Free Software Foundation, Inc.
- Contributed by Mark Mitchell (mark@markmitchell.com).
-
-This file is part of GNU CC.
-
-GNU CC is free software; you can redistribute it and/or modify it
-under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2, or (at your option)
-any later version.
-
-GNU CC is distributed in the hope that it will be useful, but
-WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
-General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with GNU CC; see the file COPYING. If not, write to
-the Free Software Foundation, 59 Temple Place - Suite 330,
-Boston, MA 02111-1307, USA. */
-
-/* For an easily readable description of splay-trees, see:
-
- Lewis, Harry R. and Denenberg, Larry. Data Structures and Their
- Algorithms. Harper-Collins, Inc. 1991. */
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h>
-#endif
-
-#include "libiberty.h"
-#include "splay-tree.h"
-
-static void splay_tree_delete_helper PARAMS((splay_tree,
- splay_tree_node));
-static void splay_tree_splay PARAMS((splay_tree,
- splay_tree_key));
-static splay_tree_node splay_tree_splay_helper
- PARAMS((splay_tree,
- splay_tree_key,
- splay_tree_node*,
- splay_tree_node*,
- splay_tree_node*));
-static int splay_tree_foreach_helper PARAMS((splay_tree,
- splay_tree_node,
- splay_tree_foreach_fn,
- void*));
-
-/* Deallocate NODE (a member of SP), and all its sub-trees. */
-
-static void
-splay_tree_delete_helper (sp, node)
- splay_tree sp;
- splay_tree_node node;
-{
- if (!node)
- return;
-
- splay_tree_delete_helper (sp, node->left);
- splay_tree_delete_helper (sp, node->right);
-
- if (sp->delete_key)
- (*sp->delete_key)(node->key);
- if (sp->delete_value)
- (*sp->delete_value)(node->value);
-
- free ((char*) node);
-}
-
-/* Help splay SP around KEY. PARENT and GRANDPARENT are the parent
- and grandparent, respectively, of NODE. */
-
-static splay_tree_node
-splay_tree_splay_helper (sp, key, node, parent, grandparent)
- splay_tree sp;
- splay_tree_key key;
- splay_tree_node *node;
- splay_tree_node *parent;
- splay_tree_node *grandparent;
-{
- splay_tree_node *next;
- splay_tree_node n;
- int comparison;
-
- n = *node;
-
- if (!n)
- return *parent;
-
- comparison = (*sp->comp) (key, n->key);
-
- if (comparison == 0)
- /* We've found the target. */
- next = 0;
- else if (comparison < 0)
- /* The target is to the left. */
- next = &n->left;
- else
- /* The target is to the right. */
- next = &n->right;
-
- if (next)
- {
- /* Continue down the tree. */
- n = splay_tree_splay_helper (sp, key, next, node, parent);
-
- /* The recursive call will change the place to which NODE
- points. */
- if (*node != n)
- return n;
- }
-
- if (!parent)
- /* NODE is the root. We are done. */
- return n;
-
- /* First, handle the case where there is no grandparent (i.e.,
- *PARENT is the root of the tree.) */
- if (!grandparent)
- {
- if (n == (*parent)->left)
- {
- *node = n->right;
- n->right = *parent;
- }
- else
- {
- *node = n->left;
- n->left = *parent;
- }
- *parent = n;
- return n;
- }
-
- /* Next handle the cases where both N and *PARENT are left children,
- or where both are right children. */
- if (n == (*parent)->left && *parent == (*grandparent)->left)
- {
- splay_tree_node p = *parent;
-
- (*grandparent)->left = p->right;
- p->right = *grandparent;
- p->left = n->right;
- n->right = p;
- *grandparent = n;
- return n;
- }
- else if (n == (*parent)->right && *parent == (*grandparent)->right)
- {
- splay_tree_node p = *parent;
-
- (*grandparent)->right = p->left;
- p->left = *grandparent;
- p->right = n->left;
- n->left = p;
- *grandparent = n;
- return n;
- }
-
- /* Finally, deal with the case where N is a left child, but *PARENT
- is a right child, or vice versa. */
- if (n == (*parent)->left)
- {
- (*parent)->left = n->right;
- n->right = *parent;
- (*grandparent)->right = n->left;
- n->left = *grandparent;
- *grandparent = n;
- return n;
- }
- else
- {
- (*parent)->right = n->left;
- n->left = *parent;
- (*grandparent)->left = n->right;
- n->right = *grandparent;
- *grandparent = n;
- return n;
- }
-}
-
-/* Splay SP around KEY. */
-
-static void
-splay_tree_splay (sp, key)
- splay_tree sp;
- splay_tree_key key;
-{
- if (sp->root == 0)
- return;
-
- splay_tree_splay_helper (sp, key, &sp->root,
- /*grandparent=*/0, /*parent=*/0);
-}
-
-/* Call FN, passing it the DATA, for every node below NODE, all of
- which are from SP, following an in-order traversal. If FN every
- returns a non-zero value, the iteration ceases immediately, and the
- value is returned. Otherwise, this function returns 0. */
-
-static int
-splay_tree_foreach_helper (sp, node, fn, data)
- splay_tree sp;
- splay_tree_node node;
- splay_tree_foreach_fn fn;
- void* data;
-{
- int val;
-
- if (!node)
- return 0;
-
- val = splay_tree_foreach_helper (sp, node->left, fn, data);
- if (val)
- return val;
-
- val = (*fn)(node, data);
- if (val)
- return val;
-
- return splay_tree_foreach_helper (sp, node->right, fn, data);
-}
-
-/* Allocate a new splay tree, using COMPARE_FN to compare nodes,
- DELETE_KEY_FN to deallocate keys, and DELETE_VALUE_FN to deallocate
- values. */
-
-splay_tree
-splay_tree_new (compare_fn, delete_key_fn, delete_value_fn)
- splay_tree_compare_fn compare_fn;
- splay_tree_delete_key_fn delete_key_fn;
- splay_tree_delete_value_fn delete_value_fn;
-{
- splay_tree sp = (splay_tree) xmalloc (sizeof (struct splay_tree_s));
- sp->root = 0;
- sp->comp = compare_fn;
- sp->delete_key = delete_key_fn;
- sp->delete_value = delete_value_fn;
-
- return sp;
-}
-
-/* Deallocate SP. */
-
-void
-splay_tree_delete (sp)
- splay_tree sp;
-{
- splay_tree_delete_helper (sp, sp->root);
- free ((char*) sp);
-}
-
-/* Insert a new node (associating KEY with DATA) into SP. If a
- previous node with the indicated KEY exists, its data is replaced
- with the new value. Returns the new node. */
-
-splay_tree_node
-splay_tree_insert (sp, key, value)
- splay_tree sp;
- splay_tree_key key;
- splay_tree_value value;
-{
- int comparison = 0;
-
- splay_tree_splay (sp, key);
-
- if (sp->root)
- comparison = (*sp->comp)(sp->root->key, key);
-
- if (sp->root && comparison == 0)
- {
- /* If the root of the tree already has the indicated KEY, just
- replace the value with VALUE. */
- if (sp->delete_value)
- (*sp->delete_value)(sp->root->value);
- sp->root->value = value;
- }
- else
- {
- /* Create a new node, and insert it at the root. */
- splay_tree_node node;
-
- node = (splay_tree_node) xmalloc (sizeof (struct splay_tree_node_s));
- node->key = key;
- node->value = value;
-
- if (!sp->root)
- node->left = node->right = 0;
- else if (comparison < 0)
- {
- node->left = sp->root;
- node->right = node->left->right;
- node->left->right = 0;
- }
- else
- {
- node->right = sp->root;
- node->left = node->right->left;
- node->right->left = 0;
- }
-
- sp->root = node;
- }
-
- return sp->root;
-}
-
-/* Lookup KEY in SP, returning VALUE if present, and NULL
- otherwise. */
-
-splay_tree_node
-splay_tree_lookup (sp, key)
- splay_tree sp;
- splay_tree_key key;
-{
- splay_tree_splay (sp, key);
-
- if (sp->root && (*sp->comp)(sp->root->key, key) == 0)
- return sp->root;
- else
- return 0;
-}
-
-/* Call FN, passing it the DATA, for every node in SP, following an
- in-order traversal. If FN every returns a non-zero value, the
- iteration ceases immediately, and the value is returned.
- Otherwise, this function returns 0. */
-
-int
-splay_tree_foreach (sp, fn, data)
- splay_tree sp;
- splay_tree_foreach_fn fn;
- void *data;
-{
- return splay_tree_foreach_helper (sp, sp->root, fn, data);
-}
-
-/* Splay-tree comparison function, treating the keys as ints. */
-
-int
-splay_tree_compare_ints (k1, k2)
- splay_tree_key k1;
- splay_tree_key k2;
-{
- if ((int) k1 < (int) k2)
- return -1;
- else if ((int) k1 > (int) k2)
- return 1;
- else
- return 0;
-}
-
-/* Splay-tree comparison function, treating the keys as pointers. */
-
-int
-splay_tree_compare_pointers (k1, k2)
- splay_tree_key k1;
- splay_tree_key k2;
-{
- if ((char*) k1 < (char*) k2)
- return -1;
- else if ((char*) k1 > (char*) k2)
- return 1;
- else
- return 0;
-}
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