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03e7853581
This used to be a minor optimization on ix86 where registers are scarce and the calling convention not very efficient, but this platform is not relevant enough anymore to warrant all this dirt in the code for the sake of saving 1 or 2% of performance. Modern platforms don't use this at all since their calling convention already defaults to using several registers so better get rid of this once for all.
585 lines
19 KiB
C
585 lines
19 KiB
C
/*
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* Elastic Binary Trees - macros and structures for operations on 64bit nodes.
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* Version 6.0.6
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* (C) 2002-2011 - Willy Tarreau <w@1wt.eu>
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*
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* This library is free software; you can redistribute it and/or
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* modify it under the terms of the GNU Lesser General Public
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* License as published by the Free Software Foundation, version 2.1
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* exclusively.
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*
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* This library is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* Lesser General Public License for more details.
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*
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* You should have received a copy of the GNU Lesser General Public
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* License along with this library; if not, write to the Free Software
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* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
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*/
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#ifndef _EB64TREE_H
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#define _EB64TREE_H
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#include "ebtree.h"
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/* Return the structure of type <type> whose member <member> points to <ptr> */
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#define eb64_entry(ptr, type, member) container_of(ptr, type, member)
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#define EB64_ROOT EB_ROOT
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#define EB64_TREE_HEAD EB_TREE_HEAD
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/* These types may sometimes already be defined */
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typedef unsigned long long u64;
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typedef signed long long s64;
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/* This structure carries a node, a leaf, and a key. It must start with the
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* eb_node so that it can be cast into an eb_node. We could also have put some
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* sort of transparent union here to reduce the indirection level, but the fact
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* is, the end user is not meant to manipulate internals, so this is pointless.
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*/
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struct eb64_node {
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struct eb_node node; /* the tree node, must be at the beginning */
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u64 key;
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};
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/*
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* Exported functions and macros.
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* Many of them are always inlined because they are extremely small, and
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* are generally called at most once or twice in a program.
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*/
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/* Return leftmost node in the tree, or NULL if none */
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static inline struct eb64_node *eb64_first(struct eb_root *root)
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{
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return eb64_entry(eb_first(root), struct eb64_node, node);
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}
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/* Return rightmost node in the tree, or NULL if none */
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static inline struct eb64_node *eb64_last(struct eb_root *root)
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{
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return eb64_entry(eb_last(root), struct eb64_node, node);
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}
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/* Return next node in the tree, or NULL if none */
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static inline struct eb64_node *eb64_next(struct eb64_node *eb64)
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{
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return eb64_entry(eb_next(&eb64->node), struct eb64_node, node);
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}
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/* Return previous node in the tree, or NULL if none */
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static inline struct eb64_node *eb64_prev(struct eb64_node *eb64)
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{
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return eb64_entry(eb_prev(&eb64->node), struct eb64_node, node);
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}
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/* Return next leaf node within a duplicate sub-tree, or NULL if none. */
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static inline struct eb64_node *eb64_next_dup(struct eb64_node *eb64)
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{
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return eb64_entry(eb_next_dup(&eb64->node), struct eb64_node, node);
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}
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/* Return previous leaf node within a duplicate sub-tree, or NULL if none. */
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static inline struct eb64_node *eb64_prev_dup(struct eb64_node *eb64)
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{
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return eb64_entry(eb_prev_dup(&eb64->node), struct eb64_node, node);
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}
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/* Return next node in the tree, skipping duplicates, or NULL if none */
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static inline struct eb64_node *eb64_next_unique(struct eb64_node *eb64)
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{
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return eb64_entry(eb_next_unique(&eb64->node), struct eb64_node, node);
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}
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/* Return previous node in the tree, skipping duplicates, or NULL if none */
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static inline struct eb64_node *eb64_prev_unique(struct eb64_node *eb64)
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{
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return eb64_entry(eb_prev_unique(&eb64->node), struct eb64_node, node);
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}
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/* Delete node from the tree if it was linked in. Mark the node unused. Note
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* that this function relies on a non-inlined generic function: eb_delete.
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*/
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static inline void eb64_delete(struct eb64_node *eb64)
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{
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eb_delete(&eb64->node);
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}
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/*
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* The following functions are not inlined by default. They are declared
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* in eb64tree.c, which simply relies on their inline version.
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*/
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struct eb64_node *eb64_lookup(struct eb_root *root, u64 x);
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struct eb64_node *eb64i_lookup(struct eb_root *root, s64 x);
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struct eb64_node *eb64_lookup_le(struct eb_root *root, u64 x);
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struct eb64_node *eb64_lookup_ge(struct eb_root *root, u64 x);
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struct eb64_node *eb64_insert(struct eb_root *root, struct eb64_node *new);
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struct eb64_node *eb64i_insert(struct eb_root *root, struct eb64_node *new);
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/*
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* The following functions are less likely to be used directly, because their
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* code is larger. The non-inlined version is preferred.
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*/
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/* Delete node from the tree if it was linked in. Mark the node unused. */
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static forceinline void __eb64_delete(struct eb64_node *eb64)
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{
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__eb_delete(&eb64->node);
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}
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/*
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* Find the first occurrence of a key in the tree <root>. If none can be
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* found, return NULL.
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*/
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static forceinline struct eb64_node *__eb64_lookup(struct eb_root *root, u64 x)
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{
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struct eb64_node *node;
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eb_troot_t *troot;
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u64 y;
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troot = root->b[EB_LEFT];
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if (unlikely(troot == NULL))
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return NULL;
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while (1) {
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if ((eb_gettag(troot) == EB_LEAF)) {
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node = container_of(eb_untag(troot, EB_LEAF),
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struct eb64_node, node.branches);
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if (node->key == x)
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return node;
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else
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return NULL;
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}
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node = container_of(eb_untag(troot, EB_NODE),
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struct eb64_node, node.branches);
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y = node->key ^ x;
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if (!y) {
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/* Either we found the node which holds the key, or
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* we have a dup tree. In the later case, we have to
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* walk it down left to get the first entry.
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*/
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if (node->node.bit < 0) {
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troot = node->node.branches.b[EB_LEFT];
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while (eb_gettag(troot) != EB_LEAF)
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troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT];
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node = container_of(eb_untag(troot, EB_LEAF),
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struct eb64_node, node.branches);
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}
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return node;
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}
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if ((y >> node->node.bit) >= EB_NODE_BRANCHES)
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return NULL; /* no more common bits */
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troot = node->node.branches.b[(x >> node->node.bit) & EB_NODE_BRANCH_MASK];
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}
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}
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/*
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* Find the first occurrence of a signed key in the tree <root>. If none can
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* be found, return NULL.
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*/
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static forceinline struct eb64_node *__eb64i_lookup(struct eb_root *root, s64 x)
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{
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struct eb64_node *node;
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eb_troot_t *troot;
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u64 key = x ^ (1ULL << 63);
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u64 y;
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troot = root->b[EB_LEFT];
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if (unlikely(troot == NULL))
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return NULL;
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while (1) {
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if ((eb_gettag(troot) == EB_LEAF)) {
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node = container_of(eb_untag(troot, EB_LEAF),
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struct eb64_node, node.branches);
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if (node->key == (u64)x)
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return node;
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else
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return NULL;
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}
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node = container_of(eb_untag(troot, EB_NODE),
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struct eb64_node, node.branches);
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y = node->key ^ x;
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if (!y) {
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/* Either we found the node which holds the key, or
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* we have a dup tree. In the later case, we have to
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* walk it down left to get the first entry.
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*/
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if (node->node.bit < 0) {
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troot = node->node.branches.b[EB_LEFT];
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while (eb_gettag(troot) != EB_LEAF)
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troot = (eb_untag(troot, EB_NODE))->b[EB_LEFT];
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node = container_of(eb_untag(troot, EB_LEAF),
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struct eb64_node, node.branches);
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}
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return node;
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}
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if ((y >> node->node.bit) >= EB_NODE_BRANCHES)
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return NULL; /* no more common bits */
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troot = node->node.branches.b[(key >> node->node.bit) & EB_NODE_BRANCH_MASK];
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}
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}
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/* Insert eb64_node <new> into subtree starting at node root <root>.
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* Only new->key needs be set with the key. The eb64_node is returned.
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* If root->b[EB_RGHT]==1, the tree may only contain unique keys.
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*/
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static forceinline struct eb64_node *
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__eb64_insert(struct eb_root *root, struct eb64_node *new) {
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struct eb64_node *old;
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unsigned int side;
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eb_troot_t *troot;
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u64 newkey; /* caching the key saves approximately one cycle */
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eb_troot_t *root_right;
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int old_node_bit;
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side = EB_LEFT;
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troot = root->b[EB_LEFT];
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root_right = root->b[EB_RGHT];
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if (unlikely(troot == NULL)) {
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/* Tree is empty, insert the leaf part below the left branch */
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root->b[EB_LEFT] = eb_dotag(&new->node.branches, EB_LEAF);
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new->node.leaf_p = eb_dotag(root, EB_LEFT);
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new->node.node_p = NULL; /* node part unused */
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return new;
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}
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/* The tree descent is fairly easy :
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* - first, check if we have reached a leaf node
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* - second, check if we have gone too far
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* - third, reiterate
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* Everywhere, we use <new> for the node node we are inserting, <root>
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* for the node we attach it to, and <old> for the node we are
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* displacing below <new>. <troot> will always point to the future node
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* (tagged with its type). <side> carries the side the node <new> is
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* attached to below its parent, which is also where previous node
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* was attached. <newkey> carries the key being inserted.
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*/
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newkey = new->key;
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while (1) {
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if (unlikely(eb_gettag(troot) == EB_LEAF)) {
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eb_troot_t *new_left, *new_rght;
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eb_troot_t *new_leaf, *old_leaf;
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old = container_of(eb_untag(troot, EB_LEAF),
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struct eb64_node, node.branches);
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new_left = eb_dotag(&new->node.branches, EB_LEFT);
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new_rght = eb_dotag(&new->node.branches, EB_RGHT);
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new_leaf = eb_dotag(&new->node.branches, EB_LEAF);
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old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
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new->node.node_p = old->node.leaf_p;
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/* Right here, we have 3 possibilities :
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- the tree does not contain the key, and we have
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new->key < old->key. We insert new above old, on
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the left ;
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- the tree does not contain the key, and we have
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new->key > old->key. We insert new above old, on
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the right ;
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- the tree does contain the key, which implies it
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is alone. We add the new key next to it as a
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first duplicate.
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The last two cases can easily be partially merged.
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*/
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if (new->key < old->key) {
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new->node.leaf_p = new_left;
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old->node.leaf_p = new_rght;
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new->node.branches.b[EB_LEFT] = new_leaf;
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new->node.branches.b[EB_RGHT] = old_leaf;
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} else {
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/* we may refuse to duplicate this key if the tree is
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* tagged as containing only unique keys.
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*/
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if ((new->key == old->key) && eb_gettag(root_right))
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return old;
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/* new->key >= old->key, new goes the right */
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old->node.leaf_p = new_left;
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new->node.leaf_p = new_rght;
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new->node.branches.b[EB_LEFT] = old_leaf;
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new->node.branches.b[EB_RGHT] = new_leaf;
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if (new->key == old->key) {
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new->node.bit = -1;
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root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
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return new;
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}
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}
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break;
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}
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/* OK we're walking down this link */
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old = container_of(eb_untag(troot, EB_NODE),
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struct eb64_node, node.branches);
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old_node_bit = old->node.bit;
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/* Stop going down when we don't have common bits anymore. We
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* also stop in front of a duplicates tree because it means we
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* have to insert above.
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*/
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if ((old_node_bit < 0) || /* we're above a duplicate tree, stop here */
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(((new->key ^ old->key) >> old_node_bit) >= EB_NODE_BRANCHES)) {
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/* The tree did not contain the key, so we insert <new> before the node
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* <old>, and set ->bit to designate the lowest bit position in <new>
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* which applies to ->branches.b[].
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*/
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eb_troot_t *new_left, *new_rght;
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eb_troot_t *new_leaf, *old_node;
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new_left = eb_dotag(&new->node.branches, EB_LEFT);
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new_rght = eb_dotag(&new->node.branches, EB_RGHT);
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new_leaf = eb_dotag(&new->node.branches, EB_LEAF);
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old_node = eb_dotag(&old->node.branches, EB_NODE);
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new->node.node_p = old->node.node_p;
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if (new->key < old->key) {
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new->node.leaf_p = new_left;
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old->node.node_p = new_rght;
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new->node.branches.b[EB_LEFT] = new_leaf;
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new->node.branches.b[EB_RGHT] = old_node;
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}
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else if (new->key > old->key) {
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old->node.node_p = new_left;
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new->node.leaf_p = new_rght;
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new->node.branches.b[EB_LEFT] = old_node;
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new->node.branches.b[EB_RGHT] = new_leaf;
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}
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else {
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struct eb_node *ret;
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ret = eb_insert_dup(&old->node, &new->node);
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return container_of(ret, struct eb64_node, node);
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}
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break;
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}
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/* walk down */
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root = &old->node.branches;
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#if BITS_PER_LONG >= 64
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side = (newkey >> old_node_bit) & EB_NODE_BRANCH_MASK;
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#else
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side = newkey;
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side >>= old_node_bit;
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if (old_node_bit >= 32) {
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side = newkey >> 32;
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side >>= old_node_bit & 0x1F;
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}
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side &= EB_NODE_BRANCH_MASK;
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#endif
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troot = root->b[side];
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}
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/* Ok, now we are inserting <new> between <root> and <old>. <old>'s
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* parent is already set to <new>, and the <root>'s branch is still in
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* <side>. Update the root's leaf till we have it. Note that we can also
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* find the side by checking the side of new->node.node_p.
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*/
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/* We need the common higher bits between new->key and old->key.
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* What differences are there between new->key and the node here ?
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* NOTE that bit(new) is always < bit(root) because highest
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* bit of new->key and old->key are identical here (otherwise they
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* would sit on different branches).
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*/
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// note that if EB_NODE_BITS > 1, we should check that it's still >= 0
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new->node.bit = fls64(new->key ^ old->key) - EB_NODE_BITS;
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root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
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return new;
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}
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/* Insert eb64_node <new> into subtree starting at node root <root>, using
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* signed keys. Only new->key needs be set with the key. The eb64_node
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* is returned. If root->b[EB_RGHT]==1, the tree may only contain unique keys.
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*/
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static forceinline struct eb64_node *
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__eb64i_insert(struct eb_root *root, struct eb64_node *new) {
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struct eb64_node *old;
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unsigned int side;
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eb_troot_t *troot;
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u64 newkey; /* caching the key saves approximately one cycle */
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eb_troot_t *root_right;
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int old_node_bit;
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side = EB_LEFT;
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troot = root->b[EB_LEFT];
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root_right = root->b[EB_RGHT];
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if (unlikely(troot == NULL)) {
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/* Tree is empty, insert the leaf part below the left branch */
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root->b[EB_LEFT] = eb_dotag(&new->node.branches, EB_LEAF);
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new->node.leaf_p = eb_dotag(root, EB_LEFT);
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new->node.node_p = NULL; /* node part unused */
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return new;
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}
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/* The tree descent is fairly easy :
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* - first, check if we have reached a leaf node
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* - second, check if we have gone too far
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* - third, reiterate
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* Everywhere, we use <new> for the node node we are inserting, <root>
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* for the node we attach it to, and <old> for the node we are
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* displacing below <new>. <troot> will always point to the future node
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* (tagged with its type). <side> carries the side the node <new> is
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* attached to below its parent, which is also where previous node
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* was attached. <newkey> carries a high bit shift of the key being
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* inserted in order to have negative keys stored before positive
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* ones.
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*/
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newkey = new->key ^ (1ULL << 63);
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while (1) {
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if (unlikely(eb_gettag(troot) == EB_LEAF)) {
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eb_troot_t *new_left, *new_rght;
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eb_troot_t *new_leaf, *old_leaf;
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old = container_of(eb_untag(troot, EB_LEAF),
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struct eb64_node, node.branches);
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new_left = eb_dotag(&new->node.branches, EB_LEFT);
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new_rght = eb_dotag(&new->node.branches, EB_RGHT);
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new_leaf = eb_dotag(&new->node.branches, EB_LEAF);
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old_leaf = eb_dotag(&old->node.branches, EB_LEAF);
|
|
|
|
new->node.node_p = old->node.leaf_p;
|
|
|
|
/* Right here, we have 3 possibilities :
|
|
- the tree does not contain the key, and we have
|
|
new->key < old->key. We insert new above old, on
|
|
the left ;
|
|
|
|
- the tree does not contain the key, and we have
|
|
new->key > old->key. We insert new above old, on
|
|
the right ;
|
|
|
|
- the tree does contain the key, which implies it
|
|
is alone. We add the new key next to it as a
|
|
first duplicate.
|
|
|
|
The last two cases can easily be partially merged.
|
|
*/
|
|
|
|
if ((s64)new->key < (s64)old->key) {
|
|
new->node.leaf_p = new_left;
|
|
old->node.leaf_p = new_rght;
|
|
new->node.branches.b[EB_LEFT] = new_leaf;
|
|
new->node.branches.b[EB_RGHT] = old_leaf;
|
|
} else {
|
|
/* we may refuse to duplicate this key if the tree is
|
|
* tagged as containing only unique keys.
|
|
*/
|
|
if ((new->key == old->key) && eb_gettag(root_right))
|
|
return old;
|
|
|
|
/* new->key >= old->key, new goes the right */
|
|
old->node.leaf_p = new_left;
|
|
new->node.leaf_p = new_rght;
|
|
new->node.branches.b[EB_LEFT] = old_leaf;
|
|
new->node.branches.b[EB_RGHT] = new_leaf;
|
|
|
|
if (new->key == old->key) {
|
|
new->node.bit = -1;
|
|
root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
|
|
return new;
|
|
}
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* OK we're walking down this link */
|
|
old = container_of(eb_untag(troot, EB_NODE),
|
|
struct eb64_node, node.branches);
|
|
old_node_bit = old->node.bit;
|
|
|
|
/* Stop going down when we don't have common bits anymore. We
|
|
* also stop in front of a duplicates tree because it means we
|
|
* have to insert above.
|
|
*/
|
|
|
|
if ((old_node_bit < 0) || /* we're above a duplicate tree, stop here */
|
|
(((new->key ^ old->key) >> old_node_bit) >= EB_NODE_BRANCHES)) {
|
|
/* The tree did not contain the key, so we insert <new> before the node
|
|
* <old>, and set ->bit to designate the lowest bit position in <new>
|
|
* which applies to ->branches.b[].
|
|
*/
|
|
eb_troot_t *new_left, *new_rght;
|
|
eb_troot_t *new_leaf, *old_node;
|
|
|
|
new_left = eb_dotag(&new->node.branches, EB_LEFT);
|
|
new_rght = eb_dotag(&new->node.branches, EB_RGHT);
|
|
new_leaf = eb_dotag(&new->node.branches, EB_LEAF);
|
|
old_node = eb_dotag(&old->node.branches, EB_NODE);
|
|
|
|
new->node.node_p = old->node.node_p;
|
|
|
|
if ((s64)new->key < (s64)old->key) {
|
|
new->node.leaf_p = new_left;
|
|
old->node.node_p = new_rght;
|
|
new->node.branches.b[EB_LEFT] = new_leaf;
|
|
new->node.branches.b[EB_RGHT] = old_node;
|
|
}
|
|
else if ((s64)new->key > (s64)old->key) {
|
|
old->node.node_p = new_left;
|
|
new->node.leaf_p = new_rght;
|
|
new->node.branches.b[EB_LEFT] = old_node;
|
|
new->node.branches.b[EB_RGHT] = new_leaf;
|
|
}
|
|
else {
|
|
struct eb_node *ret;
|
|
ret = eb_insert_dup(&old->node, &new->node);
|
|
return container_of(ret, struct eb64_node, node);
|
|
}
|
|
break;
|
|
}
|
|
|
|
/* walk down */
|
|
root = &old->node.branches;
|
|
#if BITS_PER_LONG >= 64
|
|
side = (newkey >> old_node_bit) & EB_NODE_BRANCH_MASK;
|
|
#else
|
|
side = newkey;
|
|
side >>= old_node_bit;
|
|
if (old_node_bit >= 32) {
|
|
side = newkey >> 32;
|
|
side >>= old_node_bit & 0x1F;
|
|
}
|
|
side &= EB_NODE_BRANCH_MASK;
|
|
#endif
|
|
troot = root->b[side];
|
|
}
|
|
|
|
/* Ok, now we are inserting <new> between <root> and <old>. <old>'s
|
|
* parent is already set to <new>, and the <root>'s branch is still in
|
|
* <side>. Update the root's leaf till we have it. Note that we can also
|
|
* find the side by checking the side of new->node.node_p.
|
|
*/
|
|
|
|
/* We need the common higher bits between new->key and old->key.
|
|
* What differences are there between new->key and the node here ?
|
|
* NOTE that bit(new) is always < bit(root) because highest
|
|
* bit of new->key and old->key are identical here (otherwise they
|
|
* would sit on different branches).
|
|
*/
|
|
// note that if EB_NODE_BITS > 1, we should check that it's still >= 0
|
|
new->node.bit = fls64(new->key ^ old->key) - EB_NODE_BITS;
|
|
root->b[side] = eb_dotag(&new->node.branches, EB_NODE);
|
|
|
|
return new;
|
|
}
|
|
|
|
#endif /* _EB64_TREE_H */
|