Do not fetch a node index if we have a perfectly fine pointer already at hand.
[libfirm] / heuristical.c
index cad3e8c..7605ffb 100644 (file)
 
 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 num add(num x, num y)
+{
+       if (x == INF_COSTS || y == INF_COSTS) return INF_COSTS;
+
+       return x + y;
+}
 
 static void init_buckets(void)
 {
@@ -53,6 +61,8 @@ static void fill_node_buckets(pbqp *pbqp)
 
                ARR_APP1(pbqp_node *, node_buckets[arity], node);
        }
+
+       buckets_filled = 1;
 }
 
 static void normalize_towards_source(pbqp *pbqp, pbqp_edge *edge)
@@ -93,7 +103,8 @@ static void normalize_towards_source(pbqp *pbqp, pbqp_edge *edge)
 
                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 = add(
+                                       src_vec->entries[src_index].data, min);
 
                        // TODO add to edge_list if inf
                }
@@ -137,13 +148,53 @@ static void normalize_towards_target(pbqp *pbqp, pbqp_edge *edge)
 
                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 = 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;
+
+       if (!buckets_filled) return;
+
+       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;
+       }
+
+       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);
+
+       /* ..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;
@@ -199,45 +250,12 @@ static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
                        fputs("edge has been eliminated", pbqp->dump_file);
 
                        delete_edge(edge);
+                       reorder_node(src_node);
+                       reorder_node(tgt_node);
                }
        }
 }
 
-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;
-       }
-
-       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)
 {
        unsigned node_index;
@@ -270,7 +288,7 @@ void solve_pbqp_heuristical(pbqp *pbqp)
                        pbqp_edge *edge = edges[edge_index];
 
                        /* Simplify only once per edge. */
-                       if (node_index != edge->src->index) continue;
+                       if (node != edge->src) continue;
 
                        simplify_edge(pbqp, edge);
                }
@@ -305,7 +323,8 @@ void solve_pbqp_heuristical(pbqp *pbqp)
                assert(node);
 
                node->solution = vector_get_min_index(node->costs);
-               pbqp->solution += node->costs->entries[node->solution].data;
+               pbqp->solution = 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);
@@ -384,9 +403,115 @@ void applyRI(pbqp *pbqp)
        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 applyRII(pbqp *pbqp)
+{
+       pbqp_node  **bucket     = node_buckets[1];
+       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;
+
+       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;
+
+       src_vec  = src_node->costs;
+       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);
+
+       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_index(vec);
+               }
+       }
+
+       pbqp_edge *edge = get_edge(pbqp, src_node->index, tgt_node->index);
+
+       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);
+       }
+
+       /* Disconnect node. */
+       disconnect_edge(src_node, src_edge);
+       disconnect_edge(tgt_node, tgt_edge);
+
+       /* Edge has changed so we simplify it. */
+       simplify_edge(pbqp, edge);
+}
+
 void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
 {
        pbqp_edge   *edge;
@@ -418,3 +543,16 @@ void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
                fprintf(pbqp->dump_file, "node n%d is set to %d<br>\n", node->index, node->solution);
        }
 }
+
+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;
+}