diff options
Diffstat (limited to 'src/vppinfra/fheap.c')
-rw-r--r-- | src/vppinfra/fheap.c | 473 |
1 files changed, 0 insertions, 473 deletions
diff --git a/src/vppinfra/fheap.c b/src/vppinfra/fheap.c deleted file mode 100644 index 034168e85ab..00000000000 --- a/src/vppinfra/fheap.c +++ /dev/null @@ -1,473 +0,0 @@ -/* - * Copyright (c) 2015 Cisco and/or its affiliates. - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at: - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ -#include <vppinfra/fheap.h> - -/* Fibonacci heaps. */ -always_inline fheap_node_t * -fheap_get_node (fheap_t * f, u32 i) -{ - return i != ~0 ? vec_elt_at_index (f->nodes, i) : 0; -} - -always_inline fheap_node_t * -fheap_get_root (fheap_t * f) -{ - return fheap_get_node (f, f->min_root); -} - -static void -fheap_validate (fheap_t * f) -{ - fheap_node_t *n, *m; - uword ni, si; - - if (!CLIB_DEBUG || !f->enable_validate) - return; - - vec_foreach_index (ni, f->nodes) - { - n = vec_elt_at_index (f->nodes, ni); - - if (!n->is_valid) - continue; - - /* Min root must have minimal key. */ - m = vec_elt_at_index (f->nodes, f->min_root); - ASSERT (n->key >= m->key); - - /* Min root must have no parent. */ - if (ni == f->min_root) - ASSERT (n->parent == ~0); - - /* Check sibling linkages. */ - if (n->next_sibling == ~0) - ASSERT (n->prev_sibling == ~0); - else if (n->prev_sibling == ~0) - ASSERT (n->next_sibling == ~0); - else - { - fheap_node_t *prev, *next; - u32 si = n->next_sibling, si_start = si; - do - { - m = vec_elt_at_index (f->nodes, si); - prev = vec_elt_at_index (f->nodes, m->prev_sibling); - next = vec_elt_at_index (f->nodes, m->next_sibling); - ASSERT (prev->next_sibling == si); - ASSERT (next->prev_sibling == si); - si = m->next_sibling; - } - while (si != si_start); - } - - /* Loop through all siblings. */ - { - u32 n_siblings = 0; - - foreach_fheap_node_sibling (f, si, n->next_sibling, ( - { - m = - vec_elt_at_index - (f->nodes, si); - /* All siblings must have same parent. */ - ASSERT (m->parent - == - n-> - parent); - n_siblings += 1;} - )); - - /* Either parent is non-empty or there are siblings present. */ - if (n->parent == ~0 && ni != f->min_root) - ASSERT (n_siblings > 0); - } - - /* Loop through all children. */ - { - u32 found_first_child = n->first_child == ~0; - u32 n_children = 0; - - foreach_fheap_node_sibling (f, si, n->first_child, ( - { - m = - vec_elt_at_index - (f->nodes, si); - /* Children must have larger keys than their parent. */ - ASSERT (m->key >= - n->key); - if - (!found_first_child) - found_first_child = - si == - n->first_child; - n_children += 1;} - )); - - /* Check that first child is present on list. */ - ASSERT (found_first_child); - - /* Make sure rank is correct. */ - ASSERT (n->rank == n_children); - } - } - - /* Increment serial number for each successful validate. - Failure can be used as condition for gdb breakpoints. */ - f->validate_serial++; -} - -always_inline void -fheap_node_add_sibling (fheap_t * f, u32 ni, u32 ni_to_add) -{ - fheap_node_t *n = vec_elt_at_index (f->nodes, ni); - fheap_node_t *n_to_add = vec_elt_at_index (f->nodes, ni_to_add); - fheap_node_t *n_next = fheap_get_node (f, n->next_sibling); - fheap_node_t *parent; - - /* Empty list? */ - if (n->next_sibling == ~0) - { - ASSERT (n->prev_sibling == ~0); - n->next_sibling = n->prev_sibling = ni_to_add; - n_to_add->next_sibling = n_to_add->prev_sibling = ni; - } - else - { - /* Add node after existing node. */ - n_to_add->prev_sibling = ni; - n_to_add->next_sibling = n->next_sibling; - - n->next_sibling = ni_to_add; - n_next->prev_sibling = ni_to_add; - } - - n_to_add->parent = n->parent; - parent = fheap_get_node (f, n->parent); - if (parent) - parent->rank += 1; -} - -void -fheap_add (fheap_t * f, u32 ni, u32 key) -{ - fheap_node_t *r, *n; - u32 ri; - - n = vec_elt_at_index (f->nodes, ni); - - clib_memset (n, 0, sizeof (n[0])); - n->parent = n->first_child = n->next_sibling = n->prev_sibling = ~0; - n->key = key; - - r = fheap_get_root (f); - ri = f->min_root; - if (!r) - { - /* No root? Add node as new root. */ - f->min_root = ni; - } - else - { - /* Add node as sibling of current root. */ - fheap_node_add_sibling (f, ri, ni); - - /* New node may become new root. */ - if (r->key > n->key) - f->min_root = ni; - } - - fheap_validate (f); -} - -always_inline u32 -fheap_node_remove_internal (fheap_t * f, u32 ni, u32 invalidate) -{ - fheap_node_t *n = vec_elt_at_index (f->nodes, ni); - u32 prev_ni = n->prev_sibling; - u32 next_ni = n->next_sibling; - u32 list_has_single_element = prev_ni == ni; - fheap_node_t *prev = fheap_get_node (f, prev_ni); - fheap_node_t *next = fheap_get_node (f, next_ni); - fheap_node_t *p = fheap_get_node (f, n->parent); - - if (p) - { - ASSERT (p->rank > 0); - p->rank -= 1; - p->first_child = list_has_single_element ? ~0 : next_ni; - } - - if (prev) - { - ASSERT (prev->next_sibling == ni); - prev->next_sibling = next_ni; - } - if (next) - { - ASSERT (next->prev_sibling == ni); - next->prev_sibling = prev_ni; - } - - n->prev_sibling = n->next_sibling = ni; - n->parent = ~0; - n->is_valid = invalidate == 0; - - return list_has_single_element ? ~0 : next_ni; -} - -always_inline u32 -fheap_node_remove (fheap_t * f, u32 ni) -{ - return fheap_node_remove_internal (f, ni, /* invalidate */ 0); -} - -always_inline u32 -fheap_node_remove_and_invalidate (fheap_t * f, u32 ni) -{ - return fheap_node_remove_internal (f, ni, /* invalidate */ 1); -} - -static void -fheap_link_root (fheap_t * f, u32 ni) -{ - fheap_node_t *n = vec_elt_at_index (f->nodes, ni); - fheap_node_t *r, *lo, *hi; - u32 ri, lo_i, hi_i, k; - - while (1) - { - k = n->rank; - vec_validate_init_empty (f->root_list_by_rank, k, ~0); - ri = f->root_list_by_rank[k]; - r = fheap_get_node (f, ri); - if (!r) - { - f->root_list_by_rank[k] = ni; - return; - } - - f->root_list_by_rank[k] = ~0; - - /* Sort n/r into lo/hi by their keys. */ - lo = r, lo_i = ri; - hi = n, hi_i = ni; - if (hi->key < lo->key) - { - u32 ti; - fheap_node_t *tn; - ti = lo_i, tn = lo; - lo = hi, lo_i = hi_i; - hi = tn, hi_i = ti; - } - - /* Remove larger key. */ - fheap_node_remove (f, hi_i); - - /* Add larger key as child of smaller one. */ - if (lo->first_child == ~0) - { - hi->parent = lo_i; - lo->first_child = hi_i; - lo->rank = 1; - } - else - fheap_node_add_sibling (f, lo->first_child, hi_i); - - /* Following Fredman & Trajan: "When making a root node X a child of another node in a linking step, - we unmark X". */ - hi->is_marked = 0; - - ni = lo_i; - n = lo; - } -} - -u32 -fheap_del_min (fheap_t * f, u32 * min_key) -{ - fheap_node_t *r = fheap_get_root (f); - u32 to_delete_min_ri = f->min_root; - u32 ri, ni; - - /* Empty heap? */ - if (!r) - return ~0; - - /* Root's children become siblings. Call this step a; see below. */ - if (r->first_child != ~0) - { - u32 ci, cni, rni; - fheap_node_t *c, *cn, *rn; - - /* Splice child & root circular lists together. */ - ci = r->first_child; - c = vec_elt_at_index (f->nodes, ci); - - cni = c->next_sibling; - rni = r->next_sibling; - cn = vec_elt_at_index (f->nodes, cni); - rn = vec_elt_at_index (f->nodes, rni); - - r->next_sibling = cni; - c->next_sibling = rni; - cn->prev_sibling = to_delete_min_ri; - rn->prev_sibling = ci; - } - - /* Remove min root. */ - ri = fheap_node_remove_and_invalidate (f, to_delete_min_ri); - - /* Find new min root from among siblings including the ones we've just added. */ - f->min_root = ~0; - if (ri != ~0) - { - u32 ri_last, ri_next, i, min_ds; - - r = fheap_get_node (f, ri); - ri_last = r->prev_sibling; - while (1) - { - /* Step a above can put children (with r->parent != ~0) on root list. */ - r->parent = ~0; - - ri_next = r->next_sibling; - fheap_link_root (f, ri); - if (ri == ri_last) - break; - ri = ri_next; - r = fheap_get_node (f, ri); - } - - min_ds = ~0; - vec_foreach_index (i, f->root_list_by_rank) - { - ni = f->root_list_by_rank[i]; - if (ni == ~0) - continue; - f->root_list_by_rank[i] = ~0; - r = fheap_get_node (f, ni); - if (r->key < min_ds) - { - f->min_root = ni; - min_ds = r->key; - ASSERT (r->parent == ~0); - } - } - } - - /* Return deleted min root. */ - r = vec_elt_at_index (f->nodes, to_delete_min_ri); - if (min_key) - *min_key = r->key; - - fheap_validate (f); - - return to_delete_min_ri; -} - -static void -fheap_mark_parent (fheap_t * f, u32 pi) -{ - fheap_node_t *p = vec_elt_at_index (f->nodes, pi); - - /* Parent is a root: do nothing. */ - if (p->parent == ~0) - return; - - /* If not marked, mark it. */ - if (!p->is_marked) - { - p->is_marked = 1; - return; - } - - /* Its a previously marked, non-root parent. - Cut edge to its parent and add to root list. */ - fheap_node_remove (f, pi); - fheap_node_add_sibling (f, f->min_root, pi); - - /* Unmark it since its now a root node. */ - p->is_marked = 0; - - /* "Cascading cuts": check parent. */ - if (p->parent != ~0) - fheap_mark_parent (f, p->parent); -} - -/* Set key to new smaller value. */ -void -fheap_decrease_key (fheap_t * f, u32 ni, u32 new_key) -{ - fheap_node_t *n = vec_elt_at_index (f->nodes, ni); - fheap_node_t *r = fheap_get_root (f); - - n->key = new_key; - - if (n->parent != ~0) - { - fheap_mark_parent (f, n->parent); - - /* Remove node and add to root list. */ - fheap_node_remove (f, ni); - fheap_node_add_sibling (f, f->min_root, ni); - } - - if (n->key < r->key) - f->min_root = ni; - - fheap_validate (f); -} - -void -fheap_del (fheap_t * f, u32 ni) -{ - fheap_node_t *n; - - n = vec_elt_at_index (f->nodes, ni); - - if (n->parent == ~0) - { - ASSERT (ni == f->min_root); - fheap_del_min (f, 0); - } - else - { - u32 ci; - - fheap_mark_parent (f, n->parent); - - /* Add children to root list. */ - foreach_fheap_node_sibling (f, ci, n->first_child, ( - { - fheap_node_remove - (f, ci); - fheap_node_add_sibling - (f, f->min_root, - ci);} - )); - - fheap_node_remove_and_invalidate (f, ni); - } - - fheap_validate (f); -} - -/* - * fd.io coding-style-patch-verification: ON - * - * Local Variables: - * eval: (c-set-style "gnu") - * End: - */ |