graph3.c revision 1.1
1/*	$NetBSD: graph3.c,v 1.1 2009/08/15 16:21:05 joerg Exp $	*/
2/*-
3 * Copyright (c) 2009 The NetBSD Foundation, Inc.
4 * All rights reserved.
5 *
6 * This code is derived from software contributed to The NetBSD Foundation
7 * by Joerg Sonnenberger.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 *
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in
17 *    the documentation and/or other materials provided with the
18 *    distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
26 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
27 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
28 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
29 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
30 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__RCSID("$NetBSD: graph3.c,v 1.1 2009/08/15 16:21:05 joerg Exp $");
36
37#include <err.h>
38#include <inttypes.h>
39#include <stdio.h>
40#include <stdlib.h>
41
42#include "nbperf.h"
43#include "graph3.h"
44
45static const uint32_t unused = 0xffffffffU;
46
47void
48graph3_setup(struct graph3 *graph, uint32_t v, uint32_t e)
49{
50	graph->v = v;
51	graph->e = e;
52
53	graph->verts = calloc(sizeof(struct vertex3), v);
54	graph->edges = calloc(sizeof(struct edge3), e);
55	graph->output_order = calloc(sizeof(uint32_t), e);
56
57	if (graph->verts == NULL || graph->edges == NULL ||
58	    graph->output_order == NULL)
59		err(1, "malloc failed");
60}
61
62void
63graph3_free(struct graph3 *graph)
64{
65	free(graph->verts);
66	free(graph->edges);
67	free(graph->output_order);
68
69	graph->verts = NULL;
70	graph->edges = NULL;
71	graph->output_order = NULL;
72}
73
74int
75graph3_hash(struct nbperf *nbperf, struct graph3 *graph)
76{
77	struct vertex3 *v;
78	uint32_t hashes[nbperf->hash_size];
79	size_t i;
80
81	for (i = 0; i < graph->e; ++i) {
82		(*nbperf->compute_hash)(nbperf,
83		    nbperf->keys[i], nbperf->keylens[i], hashes);
84		graph->edges[i].left = hashes[0] % graph->v;
85		graph->edges[i].middle = hashes[1] % graph->v;
86		graph->edges[i].right = hashes[2] % graph->v;
87		if (graph->edges[i].left == graph->edges[i].middle)
88			return -1;
89		if (graph->edges[i].left == graph->edges[i].right)
90			return -1;
91		if (graph->edges[i].middle == graph->edges[i].right)
92			return -1;
93	}
94
95	for (i = 0; i < graph->v; ++i) {
96		graph->verts[i].l_edge = unused;
97		graph->verts[i].m_edge = unused;
98		graph->verts[i].r_edge = unused;
99	}
100
101	for (i = 0; i < graph->e; ++i) {
102		v = &graph->verts[graph->edges[i].left];
103		if (v->l_edge != unused)
104			graph->edges[v->l_edge].l_prev = i;
105		graph->edges[i].l_next = v->l_edge;
106		graph->edges[i].l_prev = unused;
107		v->l_edge = i;
108
109		v = &graph->verts[graph->edges[i].middle];
110		if (v->m_edge != unused)
111			graph->edges[v->m_edge].m_prev = i;
112		graph->edges[i].m_next = v->m_edge;
113		graph->edges[i].m_prev = unused;
114		v->m_edge = i;
115
116		v = &graph->verts[graph->edges[i].right];
117		if (v->r_edge != unused)
118			graph->edges[v->r_edge].r_prev = i;
119		graph->edges[i].r_next = v->r_edge;
120		graph->edges[i].r_prev = unused;
121		v->r_edge = i;
122	}
123
124	return 0;
125}
126
127static void
128graph3_remove_vertex(struct graph3 *graph, struct vertex3 *v)
129{
130	struct edge3 *e;
131	struct vertex3 *vl, *vm, *vr;
132
133	if (v->l_edge != unused && v->m_edge != unused)
134		return;
135	if (v->l_edge != unused && v->r_edge != unused)
136		return;
137	if (v->m_edge != unused && v->r_edge != unused)
138		return;
139	if (v->l_edge == unused && v->m_edge == unused && v->r_edge == unused)
140		return;
141
142	if (v->l_edge != unused) {
143		e = &graph->edges[v->l_edge];
144		if (e->l_next != unused)
145			return;
146	} else if (v->m_edge != unused) {
147		e = &graph->edges[v->m_edge];
148		if (e->m_next != unused)
149			return;
150	} else {
151		if (v->r_edge == unused)
152			abort();
153		e = &graph->edges[v->r_edge];
154		if (e->r_next != unused)
155			return;
156	}
157
158	graph->output_order[--graph->output_index] = e - graph->edges;
159
160	vl = &graph->verts[e->left];
161	vm = &graph->verts[e->middle];
162	vr = &graph->verts[e->right];
163
164	if (e->l_prev == unused)
165		vl->l_edge = e->l_next;
166	else
167		graph->edges[e->l_prev].l_next = e->l_next;
168	if (e->l_next != unused)
169		graph->edges[e->l_next].l_prev = e->l_prev;
170
171	if (e->m_prev == unused)
172		vm->m_edge = e->m_next;
173	else
174		graph->edges[e->m_prev].m_next = e->m_next;
175	if (e->m_next != unused)
176		graph->edges[e->m_next].m_prev = e->m_prev;
177
178	if (e->r_prev == unused)
179		vr->r_edge = e->r_next;
180	else
181		graph->edges[e->r_prev].r_next = e->r_next;
182	if (e->r_next != unused)
183		graph->edges[e->r_next].r_prev = e->r_prev;
184}
185
186int
187graph3_output_order(struct graph3 *graph)
188{
189	struct edge3 *e;
190	size_t i;
191
192	graph->output_index = graph->e;
193
194	for (i = 0; i < graph->v; ++i)
195		graph3_remove_vertex(graph, &graph->verts[i]);
196
197	for (i = graph->e; i > 0 && i > graph->output_index;) {
198		--i;
199		e = &graph->edges[graph->output_order[i]];
200
201		graph3_remove_vertex(graph, &graph->verts[e->left]);
202		graph3_remove_vertex(graph, &graph->verts[e->middle]);
203		graph3_remove_vertex(graph, &graph->verts[e->right]);
204	}
205
206	if (graph->output_index != 0)
207		return -1;
208
209	return 0;
210}
211