X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=heuristical.c;h=23d04887db0bc0c9c0281d99333de7bece12bd54;hb=eb32c39340c33ad210747b1361f2d586198e93dc;hp=7605ffb580acf47e627893f143695cb7afb549c2;hpb=b3b7cacd85e6ac3ff0c7c6e223ce95e46eadb569;p=libfirm
diff --git a/heuristical.c b/heuristical.c
index 7605ffb58..23d04887d 100644
--- a/heuristical.c
+++ b/heuristical.c
@@ -2,6 +2,7 @@
#include "assert.h"
#include "error.h"
+#include "bucket.h"
#include "heuristical.h"
#include "html_dumper.h"
#include "kaps.h"
@@ -17,25 +18,45 @@ static pbqp_node **node_buckets[4];
static pbqp_node **reduced_bucket = NULL;
static int buckets_filled = 0;
-static num add(num x, num y)
+/* Forward declarations. */
+static void apply_Brute_Force(pbqp *pbqp);
+
+static void insert_into_edge_bucket(pbqp_edge *edge)
{
- if (x == INF_COSTS || y == INF_COSTS) return INF_COSTS;
+ if (edge_bucket_contains(edge_bucket, edge)) {
+ /* Edge is already inserted. */
+ return;
+ }
- return x + y;
+ edge_bucket_insert(&edge_bucket, edge);
}
static void init_buckets(void)
{
int i;
- edge_bucket = NEW_ARR_F(pbqp_edge *, 0);
- reduced_bucket = NEW_ARR_F(pbqp_node *, 0);
+ edge_bucket_init(&edge_bucket);
+ node_bucket_init(&reduced_bucket);
for (i = 0; i < 4; ++i) {
- node_buckets[i] = NEW_ARR_F(pbqp_node *, 0);
+ node_bucket_init(&node_buckets[i]);
}
}
+static void free_buckets(void)
+{
+ int i;
+
+ for (i = 0; i < 4; ++i) {
+ node_bucket_free(&node_buckets[i]);
+ }
+
+ edge_bucket_free(&edge_bucket);
+ node_bucket_free(&reduced_bucket);
+
+ buckets_filled = 0;
+}
+
static void fill_node_buckets(pbqp *pbqp)
{
unsigned node_index;
@@ -45,21 +66,19 @@ static void fill_node_buckets(pbqp *pbqp)
node_len = pbqp->num_nodes;
for (node_index = 0; node_index < node_len; ++node_index) {
- unsigned arity;
+ unsigned degree;
pbqp_node *node = get_node(pbqp, node_index);
if (!node) continue;
- arity = ARR_LEN(node->edges);
+ degree = pbqp_node_get_degree(node);
/* We have only one bucket for nodes with arity >= 3. */
- if (arity > 3) {
- arity = 3;
+ if (degree > 3) {
+ degree = 3;
}
- node->bucket_index = ARR_LEN(node_buckets[arity]);
-
- ARR_APP1(pbqp_node *, node_buckets[arity], node);
+ node_bucket_insert(&node_buckets[degree], node);
}
buckets_filled = 1;
@@ -102,11 +121,25 @@ static void normalize_towards_source(pbqp *pbqp, pbqp_edge *edge)
num min = pbqp_matrix_get_row_min(mat, src_index, tgt_vec);
if (min != 0) {
- pbqp_matrix_sub_row_value(mat, src_index, tgt_vec, min);
- src_vec->entries[src_index].data = add(
+ if (src_vec->entries[src_index].data == INF_COSTS) {
+ pbqp_matrix_set_row_value(mat, src_index, 0);
+ } else {
+ pbqp_matrix_sub_row_value(mat, src_index, tgt_vec, min);
+ }
+ src_vec->entries[src_index].data = pbqp_add(
src_vec->entries[src_index].data, min);
- // TODO add to edge_list if inf
+ if (min == INF_COSTS) {
+ unsigned edge_index;
+ unsigned edge_len = pbqp_node_get_degree(src_node);
+
+ for (edge_index = 0; edge_index < edge_len; ++edge_index) {
+ pbqp_edge *edge_candidate = src_node->edges[edge_index];
+ if (edge_candidate != edge) {
+ insert_into_edge_bucket(edge_candidate);
+ }
+ }
+ }
}
}
}
@@ -147,52 +180,149 @@ static void normalize_towards_target(pbqp *pbqp, pbqp_edge *edge)
num min = pbqp_matrix_get_col_min(mat, tgt_index, src_vec);
if (min != 0) {
- pbqp_matrix_sub_col_value(mat, tgt_index, src_vec, min);
- tgt_vec->entries[tgt_index].data = add(
+ if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
+ pbqp_matrix_set_col_value(mat, tgt_index, 0);
+ } else {
+ pbqp_matrix_sub_col_value(mat, tgt_index, src_vec, min);
+ }
+ tgt_vec->entries[tgt_index].data = pbqp_add(
tgt_vec->entries[tgt_index].data, min);
- // TODO add to edge_list if inf
+ if (min == INF_COSTS) {
+ unsigned edge_index;
+ unsigned edge_len = pbqp_node_get_degree(tgt_node);
+
+ for (edge_index = 0; edge_index < edge_len; ++edge_index) {
+ pbqp_edge *edge_candidate = tgt_node->edges[edge_index];
+ if (edge_candidate != edge) {
+ insert_into_edge_bucket(edge_candidate);
+ }
+ }
+ }
}
}
}
static void reorder_node(pbqp_node *node)
{
- unsigned arity;
- unsigned old_arity;
- unsigned old_bucket_len;
+ unsigned degree = pbqp_node_get_degree(node);
+ /* Assume node lost one incident edge. */
+ unsigned old_degree = degree + 1;
if (!buckets_filled) return;
- assert(node);
-
- arity = ARR_LEN(node->edges);
-
- /* Equal bucket as before */
- if (arity > 2) return;
+ /* Same bucket as before */
+ if (degree > 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) {
+ if (!node_bucket_contains(node_buckets[old_degree], node)) {
/* Old arity is new arity, so we have nothing to do. */
+ assert(node_bucket_contains(node_buckets[degree], node));
return;
}
- 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][old_bucket_len - 1]->bucket_index
- = node->bucket_index;
- 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);
+ node_bucket_remove(&node_buckets[old_degree], node);
/* ..and add to new one. */
- node->bucket_index = ARR_LEN(node_buckets[arity]);
- ARR_APP1(pbqp_node *, node_buckets[arity], node);
+ node_bucket_insert(&node_buckets[degree], node);
+}
+
+static void check_melting_possibility(pbqp *pbqp, pbqp_edge *edge)
+{
+ pbqp_matrix *mat;
+ pbqp_node *src_node;
+ pbqp_node *tgt_node;
+ vector *src_vec;
+ vector *tgt_vec;
+ int src_len;
+ int tgt_len;
+ int src_index;
+ int tgt_index;
+
+ assert(pbqp);
+ assert(edge);
+
+ src_node = edge->src;
+ tgt_node = edge->tgt;
+ assert(src_node);
+ assert(tgt_node);
+
+ src_vec = src_node->costs;
+ tgt_vec = tgt_node->costs;
+ assert(src_vec);
+ assert(tgt_vec);
+
+ src_len = src_vec->len;
+ tgt_len = tgt_vec->len;
+ assert(src_len > 0);
+ assert(tgt_len > 0);
+
+ mat = edge->costs;
+ assert(mat);
+
+ if (src_len == 1 && tgt_len == 1) {
+ //panic("Something is wrong");
+ }
+
+ int allRowsOk = 1;
+ for (src_index = 0; src_index < src_len; ++src_index) {
+ int onlyOneZero = 0;
+ if (src_vec->entries[src_index].data == INF_COSTS) {
+ continue;
+ }
+ for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
+ if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
+ continue;
+ }
+ if (mat->entries[src_index * tgt_len + tgt_index] == 0) {
+ if (onlyOneZero) {
+ onlyOneZero = 0;
+ break;
+ } else {
+ onlyOneZero = 1;
+ continue;
+ }
+ }
+ if (mat->entries[src_index * tgt_len + tgt_index] == INF_COSTS) {
+ continue;
+ }
+ onlyOneZero = 0;
+ break;
+ }
+ allRowsOk &= onlyOneZero;
+ }
+
+ int allColsOk = 1;
+ for (tgt_index = 0; tgt_index < tgt_len; ++tgt_index) {
+ int onlyOneZero = 0;
+ if (tgt_vec->entries[tgt_index].data == INF_COSTS) {
+ continue;
+ }
+ for (src_index = 0; src_index < src_len; ++src_index) {
+ if (src_vec->entries[src_index].data == INF_COSTS) {
+ continue;
+ }
+ if (mat->entries[src_index * tgt_len + tgt_index] == 0) {
+ if (onlyOneZero) {
+ onlyOneZero = 0;
+ break;
+ } else {
+ onlyOneZero = 1;
+ continue;
+ }
+ }
+ if (mat->entries[src_index * tgt_len + tgt_index] == INF_COSTS) {
+ continue;
+ }
+ onlyOneZero = 0;
+ break;
+ }
+ allColsOk &= onlyOneZero;
+ }
+
+ if (allRowsOk && allColsOk) {
+ panic("Hurray");
+ }
}
static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
@@ -213,7 +343,11 @@ static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
assert(src_node);
assert(tgt_node);
- if(pbqp->dump_file) {
+ /* If edge are already deleted, we have nothing to do. */
+ if (!is_connected(src_node, edge) || !is_connected(tgt_node, edge))
+ return;
+
+ if (pbqp->dump_file) {
char txt[100];
sprintf(txt, "Simplification of Edge n%d-n%d", src_node->index, tgt_node->index);
dump_section(pbqp->dump_file, 3, txt);
@@ -247,16 +381,18 @@ static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
if (pbqp_matrix_is_zero(mat, src_vec, tgt_vec)) {
if (pbqp->dump_file) {
- fputs("edge has been eliminated", pbqp->dump_file);
-
- delete_edge(edge);
- reorder_node(src_node);
- reorder_node(tgt_node);
+ fputs("edge has been eliminated
\n", pbqp->dump_file);
}
+
+ delete_edge(edge);
+ reorder_node(src_node);
+ reorder_node(tgt_node);
+ } else {
+ //check_melting_possibility(pbqp, edge);
}
}
-void solve_pbqp_heuristical(pbqp *pbqp)
+static void initial_simplify_edges(pbqp *pbqp)
{
unsigned node_index;
unsigned node_len;
@@ -282,7 +418,7 @@ void solve_pbqp_heuristical(pbqp *pbqp)
if (!node) continue;
edges = node->edges;
- edge_len = ARR_LEN(edges);
+ edge_len = pbqp_node_get_degree(node);
for (edge_index = 0; edge_index < edge_len; ++edge_index) {
pbqp_edge *edge = edges[edge_index];
@@ -293,62 +429,61 @@ void solve_pbqp_heuristical(pbqp *pbqp)
simplify_edge(pbqp, edge);
}
}
+}
- /* Put node into bucket representing their arity. */
- fill_node_buckets(pbqp);
-
- for (;;) {
- if (ARR_LEN(edge_bucket) > 0) {
- panic("Please implement edge simplification");
- } else if (ARR_LEN(node_buckets[1]) > 0) {
- applyRI(pbqp);
- } else if (ARR_LEN(node_buckets[2]) > 0) {
- panic("Please implement RII simplification");
- } else if (ARR_LEN(node_buckets[3]) > 0) {
- panic("Please implement RN simplification");
- } else {
- break;
- }
- }
+num determine_solution(FILE *file)
+{
+ unsigned node_index;
+ unsigned node_len;
+ num solution;
- if (pbqp->dump_file) {
- dump_section(pbqp->dump_file, 1, "4. Determine Solution/Minimum");
- dump_section(pbqp->dump_file, 2, "4.1. Trivial Solution");
+ if (file) {
+ dump_section(file, 1, "4. Determine Solution/Minimum");
+ dump_section(file, 2, "4.1. Trivial Solution");
}
/* Solve trivial nodes and calculate solution. */
- node_len = ARR_LEN(node_buckets[0]);
+ node_len = node_bucket_get_length(node_buckets[0]);
for (node_index = 0; node_index < node_len; ++node_index) {
pbqp_node *node = node_buckets[0][node_index];
assert(node);
node->solution = vector_get_min_index(node->costs);
- pbqp->solution = add(pbqp->solution,
+ solution = pbqp_add(solution,
node->costs->entries[node->solution].data);
- if (pbqp->dump_file) {
- fprintf(pbqp->dump_file, "node n%d is set to %d
\n", node->index, node->solution);
- dump_node(pbqp, node);
+ if (file) {
+ fprintf(file, "node n%d is set to %d
\n", node->index, node->solution);
+ dump_node(file, node);
}
}
+ if (file) {
+ dump_section(file, 2, "Minimum");
+ fprintf(file, "Minimum is equal to %lld.", solution);
+ }
+
+ return solution;
+}
+
+static void back_propagate(pbqp *pbqp)
+{
+ unsigned node_index;
+ unsigned node_len = node_bucket_get_length(reduced_bucket);
+
+ assert(pbqp);
if (pbqp->dump_file) {
- dump_section(pbqp->dump_file, 2, "Minimum");
- fprintf(pbqp->dump_file, "Minimum is equal to %d.", pbqp->solution);
dump_section(pbqp->dump_file, 2, "Back Propagation");
}
- /* Solve reduced nodes. */
- node_len = ARR_LEN(reduced_bucket);
for (node_index = node_len; node_index > 0; --node_index) {
pbqp_node *node = reduced_bucket[node_index - 1];
- assert(node);
- switch (ARR_LEN(node->edges)) {
+ switch (pbqp_node_get_degree(node)) {
case 1:
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");
@@ -357,11 +492,51 @@ void solve_pbqp_heuristical(pbqp *pbqp)
}
}
-void applyRI(pbqp *pbqp)
+static void apply_heuristic_reductions(pbqp *pbqp)
+{
+ for (;;) {
+ if (edge_bucket_get_length(edge_bucket) > 0) {
+ apply_edge(pbqp);
+ } else if (node_bucket_get_length(node_buckets[1]) > 0) {
+ apply_RI(pbqp);
+ } else if (node_bucket_get_length(node_buckets[2]) > 0) {
+ apply_RII(pbqp);
+ } else if (node_bucket_get_length(node_buckets[3]) > 0) {
+ apply_RN(pbqp);
+ } else {
+ return;
+ }
+ }
+}
+
+void solve_pbqp_heuristical(pbqp *pbqp)
+{
+ /* Reduce nodes degree ... */
+ initial_simplify_edges(pbqp);
+
+ /* ... and put node into bucket representing their degree. */
+ fill_node_buckets(pbqp);
+
+ apply_heuristic_reductions(pbqp);
+
+ pbqp->solution = determine_solution(pbqp->dump_file);
+
+ /* Solve reduced nodes. */
+ back_propagate(pbqp);
+
+ free_buckets();
+}
+
+void apply_edge(pbqp *pbqp)
{
- pbqp_node **bucket = node_buckets[1];
- unsigned bucket_len = ARR_LEN(bucket);
- pbqp_node *node = bucket[bucket_len - 1];
+ pbqp_edge *edge = edge_bucket_pop(&edge_bucket);
+
+ simplify_edge(pbqp, edge);
+}
+
+void apply_RI(pbqp *pbqp)
+{
+ pbqp_node *node = node_bucket_pop(&node_buckets[1]);
pbqp_edge *edge = node->edges[0];
pbqp_matrix *mat = edge->costs;
int is_src = edge->src == node;
@@ -375,13 +550,13 @@ void applyRI(pbqp *pbqp)
if (pbqp->dump_file) {
char txt[100];
- sprintf(txt, "RI-Reduktion of Node n%d", node->index);
+ sprintf(txt, "RI-Reduction of Node n%d", node->index);
dump_section(pbqp->dump_file, 2, txt);
pbqp_dump_graph(pbqp);
fputs("
\nBefore reduction:
\n", pbqp->dump_file);
- dump_node(pbqp, node);
- dump_node(pbqp, other_node);
- dump_edge(pbqp, edge);
+ dump_node(pbqp->dump_file, node);
+ dump_node(pbqp->dump_file, other_node);
+ dump_edge(pbqp->dump_file, edge);
}
if (is_src) {
@@ -395,23 +570,18 @@ void applyRI(pbqp *pbqp)
if (pbqp->dump_file) {
fputs("
\nAfter reduction:
\n", pbqp->dump_file);
- dump_node(pbqp, other_node);
+ dump_node(pbqp->dump_file, other_node);
}
- /* Remove node from bucket... */
- ARR_SHRINKLEN(bucket, (int)bucket_len - 1);
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);
+ /* Add node to back propagation list. */
+ node_bucket_insert(&reduced_bucket, node);
}
-void applyRII(pbqp *pbqp)
+void apply_RII(pbqp *pbqp)
{
- pbqp_node **bucket = node_buckets[1];
- unsigned bucket_len = ARR_LEN(bucket);
- pbqp_node *node = bucket[bucket_len - 1];
+ pbqp_node *node = node_bucket_pop(&node_buckets[2]);
pbqp_edge *src_edge = node->edges[0];
pbqp_edge *tgt_edge = node->edges[1];
int src_is_src = src_edge->src == node;
@@ -431,6 +601,8 @@ void applyRII(pbqp *pbqp)
unsigned row_len;
unsigned node_len;
+ assert(pbqp);
+
if (src_is_src) {
src_node = src_edge->tgt;
} else {
@@ -460,6 +632,19 @@ void applyRII(pbqp *pbqp)
tgt_is_src = tgt_edge->src == node;
}
+ if (pbqp->dump_file) {
+ char txt[100];
+ sprintf(txt, "RII-Reduction of Node n%d", node->index);
+ dump_section(pbqp->dump_file, 2, txt);
+ pbqp_dump_graph(pbqp);
+ fputs("
\nBefore reduction:
\n", pbqp->dump_file);
+ dump_node(pbqp->dump_file, src_node);
+ dump_edge(pbqp->dump_file, src_edge);
+ dump_node(pbqp->dump_file, node);
+ dump_edge(pbqp->dump_file, tgt_edge);
+ dump_node(pbqp->dump_file, tgt_node);
+ }
+
src_mat = src_edge->costs;
tgt_mat = tgt_edge->costs;
@@ -467,9 +652,9 @@ void applyRII(pbqp *pbqp)
tgt_vec = tgt_node->costs;
node_vec = node->costs;
- row_len = ARR_LEN(src_vec);
- col_len = ARR_LEN(tgt_vec);
- node_len = ARR_LEN(node_vec);
+ row_len = src_vec->len;
+ col_len = tgt_vec->len;
+ node_len = node_vec->len;
mat = pbqp_matrix_alloc(pbqp, row_len, col_len);
@@ -489,12 +674,21 @@ void applyRII(pbqp *pbqp)
vector_add_matrix_row(vec, tgt_mat, col_index);
}
- mat->entries[row_index * col_len + col_index] = vector_get_min_index(vec);
+ 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);
+
+ /* Add node to back propagation list. */
+ node_bucket_insert(&reduced_bucket, node);
+
if (edge == NULL) {
edge = alloc_edge(pbqp, src_node->index, tgt_node->index, mat);
} else {
@@ -502,16 +696,271 @@ void applyRII(pbqp *pbqp)
/* Free local matrix. */
obstack_free(&pbqp->obstack, mat);
+
+ reorder_node(src_node);
+ reorder_node(tgt_node);
}
- /* Disconnect node. */
- disconnect_edge(src_node, src_edge);
- disconnect_edge(tgt_node, tgt_edge);
+ if (pbqp->dump_file) {
+ fputs("
\nAfter reduction:
\n", pbqp->dump_file);
+ dump_edge(pbqp->dump_file, edge);
+ }
/* Edge has changed so we simplify it. */
simplify_edge(pbqp, edge);
}
+static void select_alternative(pbqp_node *node, unsigned selected_index)
+{
+ unsigned edge_index;
+ unsigned node_index;
+ unsigned node_len;
+ vector *node_vec;
+ unsigned max_degree = pbqp_node_get_degree(node);
+
+ assert(selected_index < max_degree);
+ assert(node);
+ node->solution = selected_index;
+ node_vec = node->costs;
+ node_len = node_vec->len;
+
+ /* Set all other costs to infinity. */
+ for (node_index = 0; node_index < node_len; ++node_index) {
+ if (node_index != selected_index) {
+ node_vec->entries[node_index].data = INF_COSTS;
+ }
+ }
+
+ /* Add all incident edges to edge bucket, since they are now independent. */
+ for (edge_index = 0; edge_index < max_degree; ++edge_index) {
+ insert_into_edge_bucket(node->edges[edge_index]);
+ }
+}
+
+static pbqp_node *get_node_with_max_degree(void)
+{
+ pbqp_node **bucket = node_buckets[3];
+ unsigned bucket_len = node_bucket_get_length(bucket);
+ unsigned bucket_index;
+ unsigned max_degree = 0;
+ pbqp_node *result = NULL;
+
+ for (bucket_index = 0; bucket_index < bucket_len; ++bucket_index) {
+ pbqp_node *candidate = bucket[bucket_index];
+ unsigned degree = pbqp_node_get_degree(candidate);
+
+ if (degree > max_degree) {
+ result = candidate;
+ max_degree = degree;
+ }
+ }
+
+ return result;
+}
+
+static unsigned get_local_minimal_alternative(pbqp *pbqp, pbqp_node *node)
+{
+ pbqp_edge *edge;
+ vector *node_vec;
+ vector *vec;
+ pbqp_matrix *mat;
+ unsigned edge_index;
+ unsigned max_degree = 0;
+ unsigned node_index;
+ unsigned node_len;
+ unsigned min_index = 0;
+ num min = INF_COSTS;
+ int is_src;
+
+ assert(pbqp);
+ assert(node);
+ node_vec = node->costs;
+ node_len = node_vec->len;
+
+ for (node_index = 0; node_index < node_len; ++node_index) {
+ num value = node_vec->entries[node_index].data;
+
+ for (edge_index = 0; edge_index < max_degree; ++edge_index) {
+ edge = node->edges[edge_index];
+ mat = edge->costs;
+ is_src = edge->src == node;
+
+ if (is_src) {
+ vec = vector_copy(pbqp, edge->tgt->costs);
+ vector_add_matrix_row(vec, mat, node_index);
+ } else {
+ vec = vector_copy(pbqp, edge->src->costs);
+ vector_add_matrix_col(vec, mat, node_index);
+ }
+
+ value = pbqp_add(value, vector_get_min(vec));
+
+ obstack_free(&pbqp->obstack, vec);
+ }
+
+ if (value < min) {
+ min = value;
+ min_index = node_index;
+ }
+ }
+
+ return min_index;
+}
+
+void apply_RN(pbqp *pbqp)
+{
+ pbqp_node *node = NULL;
+ unsigned min_index = 0;
+
+ assert(pbqp);
+
+ /* We want to reduce a node with maximum degree. */
+ node = get_node_with_max_degree();
+ assert(node);
+
+ if (pbqp->dump_file) {
+ char txt[100];
+ sprintf(txt, "RN-Reduction of Node n%d", node->index);
+ dump_section(pbqp->dump_file, 2, txt);
+ pbqp_dump_graph(pbqp);
+ }
+
+ min_index = get_local_minimal_alternative(pbqp, node);
+
+ if (pbqp->dump_file) {
+ fprintf(pbqp->dump_file, "node n%d is set to %d
\n",
+ node->index, min_index);
+ }
+
+ /* Now that we found the local minimum set all other costs to infinity. */
+ select_alternative(node, min_index);
+}
+
+static void apply_brute_force_reductions(pbqp *pbqp)
+{
+ for (;;) {
+ if (edge_bucket_get_length(edge_bucket) > 0) {
+ apply_edge(pbqp);
+ } else if (node_bucket_get_length(node_buckets[1]) > 0) {
+ apply_RI(pbqp);
+ } else if (node_bucket_get_length(node_buckets[2]) > 0) {
+ apply_RII(pbqp);
+ } else if (node_bucket_get_length(node_buckets[3]) > 0) {
+ apply_Brute_Force(pbqp);
+ } else {
+ return;
+ }
+ }
+}
+
+static unsigned get_minimal_alternative(pbqp *pbqp, pbqp_node *node)
+{
+ vector *node_vec;
+ unsigned node_index;
+ unsigned node_len;
+ unsigned min_index = 0;
+ num min = INF_COSTS;
+
+ assert(pbqp);
+ assert(node);
+ node_vec = node->costs;
+ node_len = node_vec->len;
+
+ for (node_index = 0; node_index < node_len; ++node_index) {
+ num value;
+
+ /* Some node buckets and the edge bucket should be empty. */
+ assert(node_bucket_get_length(node_buckets[1]) == 0);
+ assert(node_bucket_get_length(node_buckets[2]) == 0);
+ assert(edge_bucket_get_length(edge_bucket) == 0);
+
+ /* Save current PBQP state. */
+ pbqp_node_bucket *bucket_deg0 = node_bucket_deep_copy(node_buckets[0]);
+ pbqp_node_bucket *bucket_deg3 = node_bucket_deep_copy(node_buckets[3]);
+ pbqp_node_bucket *bucket_red = node_bucket_deep_copy(reduced_bucket);
+
+ /* Select alternative and solve PBQP recursively. */
+ select_alternative(node, node_index);
+ apply_brute_force_reductions(pbqp);
+
+ value = determine_solution(pbqp->dump_file);
+
+ if (value < min) {
+ min = value;
+ min_index = node_index;
+ }
+
+ /* Some node buckets and the edge bucket should still be empty. */
+ assert(node_bucket_get_length(node_buckets[1]) == 0);
+ assert(node_bucket_get_length(node_buckets[2]) == 0);
+ assert(edge_bucket_get_length(edge_bucket) == 0);
+
+ /* Clear modified buckets... */
+ node_bucket_clear(&node_buckets[0]);
+ node_bucket_clear(&node_buckets[3]);
+ node_bucket_clear(&reduced_bucket);
+
+ /* ... and restore old PBQP state. */
+ node_bucket_copy(&node_buckets[0], bucket_deg0);
+ node_bucket_copy(&node_buckets[3], bucket_deg3);
+ node_bucket_copy(&reduced_bucket, bucket_red);
+
+ /* Free copies. */
+ node_bucket_free(bucket_deg0);
+ node_bucket_free(bucket_deg3);
+ node_bucket_free(bucket_red);
+ }
+
+ return min_index;
+}
+
+void apply_Brute_Force(pbqp *pbqp)
+{
+ pbqp_node *node = NULL;
+ unsigned min_index = 0;
+
+ assert(pbqp);
+
+ /* We want to reduce a node with maximum degree. */
+ node = get_node_with_max_degree();
+ assert(node);
+
+ if (pbqp->dump_file) {
+ char txt[100];
+ sprintf(txt, "BF-Reduction of Node n%d", node->index);
+ dump_section(pbqp->dump_file, 2, txt);
+ pbqp_dump_graph(pbqp);
+ }
+
+ min_index = get_minimal_alternative(pbqp, node);
+
+ if (pbqp->dump_file) {
+ fprintf(pbqp->dump_file, "node n%d is set to %d
\n",
+ node->index, min_index);
+ }
+
+ /* Now that we found the minimum set all other costs to infinity. */
+ select_alternative(node, min_index);
+}
+
+void solve_pbqp_brute_force(pbqp *pbqp)
+{
+ /* Reduce nodes degree ... */
+ initial_simplify_edges(pbqp);
+
+ /* ... and put node into bucket representing their degree. */
+ fill_node_buckets(pbqp);
+
+ apply_brute_force_reductions(pbqp);
+
+ pbqp->solution = determine_solution(pbqp->dump_file);
+
+ /* Solve reduced nodes. */
+ back_propagate(pbqp);
+
+ free_buckets();
+}
+
void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
{
pbqp_edge *edge;
@@ -544,15 +993,87 @@ void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
}
}
+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
\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;
+ if (pbqp_node_get_degree(node) == 0) return 1;
- return bucket_index < bucket_length && reduced_bucket[bucket_index] == node;
+ return node_bucket_contains(reduced_bucket, node);
}