static pbqp_edge **edge_bucket;
static pbqp_node **node_buckets[4];
-static pbqp_node **reduced_bucket;
+static pbqp_node **reduced_bucket = NULL;
+static int buckets_filled = 0;
static void init_buckets(void)
{
}
}
+static void free_buckets(void)
+{
+ int i;
+
+ for (i = 0; i < 4; ++i) {
+ DEL_ARR_F(node_buckets[i]);
+ }
+
+ DEL_ARR_F(edge_bucket);
+ DEL_ARR_F(reduced_bucket);
+
+ buckets_filled = 0;
+}
+
static void fill_node_buckets(pbqp *pbqp)
{
unsigned node_index;
ARR_APP1(pbqp_node *, node_buckets[arity], node);
}
+
+ buckets_filled = 1;
}
static void normalize_towards_source(pbqp *pbqp, pbqp_edge *edge)
assert(pbqp);
assert(edge);
- src_node = get_node(pbqp, edge->src);
- tgt_node = get_node(pbqp, edge->tgt);
+ src_node = edge->src;
+ tgt_node = edge->tgt;
assert(src_node);
assert(tgt_node);
if (min != 0) {
pbqp_matrix_sub_row_value(mat, src_index, tgt_vec, min);
- src_vec->entries[src_index].data += min;
+ src_vec->entries[src_index].data = pbqp_add(
+ src_vec->entries[src_index].data, min);
// TODO add to edge_list if inf
}
assert(pbqp);
assert(edge);
- src_node = get_node(pbqp, edge->src);
- tgt_node = get_node(pbqp, edge->tgt);
+ src_node = edge->src;
+ tgt_node = edge->tgt;
assert(src_node);
assert(tgt_node);
if (min != 0) {
pbqp_matrix_sub_col_value(mat, tgt_index, src_vec, min);
- tgt_vec->entries[tgt_index].data += min;
+ tgt_vec->entries[tgt_index].data = pbqp_add(
+ tgt_vec->entries[tgt_index].data, min);
// TODO add to edge_list if inf
}
}
}
+static void reorder_node(pbqp_node *node)
+{
+ unsigned arity;
+ unsigned old_arity;
+ unsigned old_bucket_len;
+ unsigned old_bucket_index;
+ pbqp_node **old_bucket;
+ pbqp_node *other;
+
+ if (!buckets_filled) return;
+
+ assert(node);
+
+ arity = ARR_LEN(node->edges);
+
+ /* Same bucket as before */
+ if (arity > 2) return;
+
+ /* Assume node lost one incident edge. */
+ old_arity = arity + 1;
+ old_bucket = node_buckets[old_arity];
+ old_bucket_len = ARR_LEN(old_bucket);
+ old_bucket_index = node->bucket_index;
+
+ if (old_bucket_len <= old_bucket_index ||
+ old_bucket[old_bucket_index] != node) {
+ /* Old arity is new arity, so we have nothing to do. */
+ assert(old_bucket_index < ARR_LEN(node_buckets[arity]) &&
+ node_buckets[arity][old_bucket_index] == node);
+ return;
+ }
+
+ assert(old_bucket[old_bucket_index] == node);
+
+ /* Delete node from old bucket... */
+ other = old_bucket[old_bucket_len - 1];
+ other->bucket_index = old_bucket_index;
+ old_bucket[old_bucket_index] = other;
+ ARR_SHRINKLEN(node_buckets[old_arity], old_bucket_len - 1);
+
+ /* ..and add to new one. */
+ node->bucket_index = ARR_LEN(node_buckets[arity]);
+ ARR_APP1(pbqp_node*, node_buckets[arity], node);
+}
+
static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
{
pbqp_matrix *mat;
assert(pbqp);
assert(edge);
- if(pbqp->dump_file) {
+ src_node = edge->src;
+ tgt_node = edge->tgt;
+ assert(src_node);
+ assert(tgt_node);
+
+ if (pbqp->dump_file) {
char txt[100];
- sprintf(txt, "Simplification of Edge n%d-n%d", edge->src, edge->tgt);
+ sprintf(txt, "Simplification of Edge n%d-n%d", src_node->index, tgt_node->index);
dump_section(pbqp->dump_file, 3, txt);
}
- src_node = get_node(pbqp, edge->src);
- tgt_node = get_node(pbqp, edge->tgt);
- assert(src_node);
- assert(tgt_node);
-
src_vec = src_node->costs;
tgt_vec = tgt_node->costs;
assert(src_vec);
if (pbqp_matrix_is_zero(mat, src_vec, tgt_vec)) {
if (pbqp->dump_file) {
- fputs("edge has been eliminated", pbqp->dump_file);
-
- delete_edge(pbqp, edge);
+ fputs("edge has been eliminated<br>\n", pbqp->dump_file);
}
- }
-}
-
-static void reorder_node(pbqp_node *node)
-{
- unsigned arity;
- unsigned old_arity;
- unsigned old_bucket_len;
-
- assert(node);
-
- arity = ARR_LEN(node->edges);
-
- /* Equal bucket as before */
- if (arity > 2) return;
-
- /* Assume node lost one incident edge. */
- old_arity = arity + 1;
- if (ARR_LEN(node_buckets[old_arity]) <= (int)node->bucket_index
- || node_buckets[old_arity][node->bucket_index] != node) {
- /* Old arity is new arity, so we have nothing to do. */
- return;
+ delete_edge(edge);
+ reorder_node(src_node);
+ reorder_node(tgt_node);
}
-
- old_bucket_len = ARR_LEN(node_buckets[old_arity]);
- assert (node_buckets[old_arity][node->bucket_index] == node);
-
- /* Delete node from old bucket... */
- node_buckets[old_arity][node->bucket_index]
- = node_buckets[old_arity][old_bucket_len - 1];
- ARR_SHRINKLEN(node_buckets[old_arity], (int)old_bucket_len - 1);
-
- /* ..and add to new one. */
- node->bucket_index = ARR_LEN(node_buckets[arity]);
- ARR_APP1(pbqp_node *, node_buckets[arity], node);
}
void solve_pbqp_heuristical(pbqp *pbqp)
pbqp_edge *edge = edges[edge_index];
/* Simplify only once per edge. */
- if (node_index != edge->src) continue;
+ if (node != edge->src) continue;
simplify_edge(pbqp, edge);
}
if (ARR_LEN(edge_bucket) > 0) {
panic("Please implement edge simplification");
} else if (ARR_LEN(node_buckets[1]) > 0) {
- applyRI(pbqp);
+ apply_RI(pbqp);
} else if (ARR_LEN(node_buckets[2]) > 0) {
- panic("Please implement RII simplification");
+ apply_RII(pbqp);
} else if (ARR_LEN(node_buckets[3]) > 0) {
panic("Please implement RN simplification");
} else {
assert(node);
node->solution = vector_get_min_index(node->costs);
- pbqp->solution += node->costs->entries[node->solution].data;
+ pbqp->solution = pbqp_add(pbqp->solution,
+ node->costs->entries[node->solution].data);
if (pbqp->dump_file) {
fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
- dump_node(pbqp, node->index);
+ dump_node(pbqp, node);
}
}
back_propagate_RI(pbqp, node);
break;
case 2:
- panic("Please implement back propagation for RII");
+ back_propagate_RII(pbqp, node);
break;
default:
panic("Only nodes with degree one or two should be in this bucket");
break;
}
}
+
+ free_buckets();
}
-void applyRI(pbqp *pbqp)
+void apply_RI(pbqp *pbqp)
{
pbqp_node **bucket = node_buckets[1];
unsigned bucket_len = ARR_LEN(bucket);
pbqp_node *node = bucket[bucket_len - 1];
pbqp_edge *edge = node->edges[0];
pbqp_matrix *mat = edge->costs;
- int is_src = get_node(pbqp, edge->src) == node;
- unsigned my_index;
- unsigned other_index;
+ int is_src = edge->src == node;
+ pbqp_node *other_node;
if (is_src) {
- my_index = edge->src;
- other_index = edge->tgt;
+ other_node = edge->tgt;
} else {
- my_index = edge->tgt;
- other_index = edge->src;
+ other_node = edge->src;
}
if (pbqp->dump_file) {
char txt[100];
- sprintf(txt, "RI-Reduktion of Node n%d", my_index);
+ sprintf(txt, "RI-Reduktion of Node n%d", node->index);
dump_section(pbqp->dump_file, 2, txt);
pbqp_dump_graph(pbqp);
fputs("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
- dump_node(pbqp, my_index);
- dump_node(pbqp, other_index);
+ dump_node(pbqp, node);
+ dump_node(pbqp, other_node);
dump_edge(pbqp, edge);
}
if (is_src) {
- pbqp_node *tgt_node = get_node(pbqp, edge->tgt);
pbqp_matrix_add_to_all_cols(mat, node->costs);
normalize_towards_target(pbqp, edge);
- disconnect_edge(tgt_node, edge);
} else {
- pbqp_node *src_node = get_node(pbqp, edge->src);
pbqp_matrix_add_to_all_rows(mat, node->costs);
- dump_edge(pbqp, edge);
normalize_towards_source(pbqp, edge);
- disconnect_edge(src_node, edge);
}
+ disconnect_edge(other_node, edge);
if (pbqp->dump_file) {
fputs("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
- dump_node(pbqp, other_index);
+ dump_node(pbqp, other_node);
}
/* Remove node from bucket... */
ARR_SHRINKLEN(bucket, (int)bucket_len - 1);
- reorder_node(get_node(pbqp, other_index));
+ reorder_node(other_node);
/* ...and add it to back propagation list. */
+ node->bucket_index = ARR_LEN(reduced_bucket);
ARR_APP1(pbqp_node *, reduced_bucket, node);
}
+void apply_RII(pbqp *pbqp)
+{
+ pbqp_node **bucket = node_buckets[2];
+ unsigned bucket_len = ARR_LEN(bucket);
+ pbqp_node *node = bucket[bucket_len - 1];
+ pbqp_edge *src_edge = node->edges[0];
+ pbqp_edge *tgt_edge = node->edges[1];
+ int src_is_src = src_edge->src == node;
+ int tgt_is_src = tgt_edge->src == node;
+ pbqp_matrix *src_mat;
+ pbqp_matrix *tgt_mat;
+ pbqp_node *src_node;
+ pbqp_node *tgt_node;
+ pbqp_matrix *mat;
+ vector *vec;
+ vector *node_vec;
+ vector *src_vec;
+ vector *tgt_vec;
+ unsigned col_index;
+ unsigned col_len;
+ unsigned row_index;
+ unsigned row_len;
+ unsigned node_len;
+
+ assert(pbqp);
+
+ if (src_is_src) {
+ src_node = src_edge->tgt;
+ } else {
+ src_node = src_edge->src;
+ }
+
+ if (tgt_is_src) {
+ tgt_node = tgt_edge->tgt;
+ } else {
+ tgt_node = tgt_edge->src;
+ }
+
+ /* Swap nodes if necessary. */
+ if (tgt_node->index < src_node->index) {
+ pbqp_node *tmp_node;
+ pbqp_edge *tmp_edge;
+
+ tmp_node = src_node;
+ src_node = tgt_node;
+ tgt_node = tmp_node;
+
+ tmp_edge = src_edge;
+ src_edge = tgt_edge;
+ tgt_edge = tmp_edge;
+
+ src_is_src = src_edge->src == node;
+ tgt_is_src = tgt_edge->src == node;
+ }
+
+ if (pbqp->dump_file) {
+ char txt[100];
+ sprintf(txt, "RII-Reduktion of Node n%d", node->index);
+ dump_section(pbqp->dump_file, 2, txt);
+ pbqp_dump_graph(pbqp);
+ fputs("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
+ dump_node(pbqp, src_node);
+ dump_edge(pbqp, src_edge);
+ dump_node(pbqp, node);
+ dump_edge(pbqp, tgt_edge);
+ dump_node(pbqp, tgt_node);
+ }
+
+ src_mat = src_edge->costs;
+ tgt_mat = tgt_edge->costs;
+
+ src_vec = src_node->costs;
+ tgt_vec = tgt_node->costs;
+ node_vec = node->costs;
+
+ row_len = src_vec->len;
+ col_len = tgt_vec->len;
+ node_len = node_vec->len;
+
+ mat = pbqp_matrix_alloc(pbqp, row_len, col_len);
+
+ for (row_index = 0; row_index < row_len; ++row_index) {
+ for (col_index = 0; col_index < col_len; ++col_index) {
+ vec = vector_copy(pbqp, node_vec);
+
+ if (src_is_src) {
+ vector_add_matrix_col(vec, src_mat, row_index);
+ } else {
+ vector_add_matrix_row(vec, src_mat, row_index);
+ }
+
+ if (tgt_is_src) {
+ vector_add_matrix_col(vec, tgt_mat, col_index);
+ } else {
+ vector_add_matrix_row(vec, tgt_mat, col_index);
+ }
+
+ mat->entries[row_index * col_len + col_index] = vector_get_min(vec);
+
+ obstack_free(&pbqp->obstack, vec);
+ }
+ }
+
+ pbqp_edge *edge = get_edge(pbqp, src_node->index, tgt_node->index);
+
+ /* Disconnect node. */
+ disconnect_edge(src_node, src_edge);
+ disconnect_edge(tgt_node, tgt_edge);
+
+ /* Remove node from bucket... */
+ ARR_SHRINKLEN(bucket, (int)bucket_len - 1);
+
+ /* ...and add it to back propagation list. */
+ node->bucket_index = ARR_LEN(reduced_bucket);
+ ARR_APP1(pbqp_node *, reduced_bucket, node);
+
+ if (edge == NULL) {
+ edge = alloc_edge(pbqp, src_node->index, tgt_node->index, mat);
+ } else {
+ pbqp_matrix_add(edge->costs, mat);
+
+ /* Free local matrix. */
+ obstack_free(&pbqp->obstack, mat);
+
+ reorder_node(src_node);
+ reorder_node(tgt_node);
+ }
+
+ if (pbqp->dump_file) {
+ fputs("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
+ dump_edge(pbqp, edge);
+ }
+
+ /* Edge has changed so we simplify it. */
+ simplify_edge(pbqp, edge);
+}
+
void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
{
pbqp_edge *edge;
edge = node->edges[0];
mat = edge->costs;
- is_src = get_node(pbqp, edge->src) == node;
+ is_src = edge->src == node;
vec = node->costs;
if (is_src) {
- other = get_node(pbqp, edge->tgt);
+ other = edge->tgt;
assert(other);
vector_add_matrix_col(vec, mat, other->solution);
} else {
- other = get_node(pbqp, edge->src);
+ other = edge->src;
assert(other);
vector_add_matrix_row(vec, mat, other->solution);
}
fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
}
}
+
+void back_propagate_RII(pbqp *pbqp, pbqp_node *node)
+{
+ pbqp_edge *src_edge = node->edges[0];
+ pbqp_edge *tgt_edge = node->edges[1];
+ int src_is_src = src_edge->src == node;
+ int tgt_is_src = tgt_edge->src == node;
+ pbqp_matrix *src_mat;
+ pbqp_matrix *tgt_mat;
+ pbqp_node *src_node;
+ pbqp_node *tgt_node;
+ vector *vec;
+ vector *node_vec;
+ unsigned col_index;
+ unsigned row_index;
+
+ assert(pbqp);
+
+ if (src_is_src) {
+ src_node = src_edge->tgt;
+ } else {
+ src_node = src_edge->src;
+ }
+
+ if (tgt_is_src) {
+ tgt_node = tgt_edge->tgt;
+ } else {
+ tgt_node = tgt_edge->src;
+ }
+
+ /* Swap nodes if necessary. */
+ if (tgt_node->index < src_node->index) {
+ pbqp_node *tmp_node;
+ pbqp_edge *tmp_edge;
+
+ tmp_node = src_node;
+ src_node = tgt_node;
+ tgt_node = tmp_node;
+
+ tmp_edge = src_edge;
+ src_edge = tgt_edge;
+ tgt_edge = tmp_edge;
+
+ src_is_src = src_edge->src == node;
+ tgt_is_src = tgt_edge->src == node;
+ }
+
+ src_mat = src_edge->costs;
+ tgt_mat = tgt_edge->costs;
+
+ node_vec = node->costs;
+
+ row_index = src_node->solution;
+ col_index = tgt_node->solution;
+
+ vec = vector_copy(pbqp, node_vec);
+
+ if (src_is_src) {
+ vector_add_matrix_col(vec, src_mat, row_index);
+ } else {
+ vector_add_matrix_row(vec, src_mat, row_index);
+ }
+
+ if (tgt_is_src) {
+ vector_add_matrix_col(vec, tgt_mat, col_index);
+ } else {
+ vector_add_matrix_row(vec, tgt_mat, col_index);
+ }
+
+ node->solution = vector_get_min_index(vec);
+ if (pbqp->dump_file) {
+ fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
+ }
+
+ obstack_free(&pbqp->obstack, vec);
+}
+
+int node_is_reduced(pbqp_node *node)
+{
+ if (!reduced_bucket) return 0;
+
+ assert(node);
+ if (ARR_LEN(node->edges) == 0) return 1;
+
+ unsigned bucket_length = ARR_LEN(reduced_bucket);
+ unsigned bucket_index = node->bucket_index;
+
+ return bucket_index < bucket_length && reduced_bucket[bucket_index] == node;
+}