Use more bucket functions.
[libfirm] / heuristical.c
index 4fb18ce..2f3e38d 100644 (file)
@@ -2,6 +2,7 @@
 #include "assert.h"
 #include "error.h"
 
+#include "bucket.h"
 #include "heuristical.h"
 #include "html_dumper.h"
 #include "kaps.h"
@@ -17,16 +18,40 @@ static pbqp_node **node_buckets[4];
 static pbqp_node **reduced_bucket = NULL;
 static int         buckets_filled = 0;
 
+static void insert_into_edge_bucket(pbqp_edge *edge)
+{
+       if (edge_bucket_contains(edge_bucket, edge)) {
+               /* Edge is already inserted. */
+               return;
+       }
+
+       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_bucket_init(&node_buckets[i]);
+       }
+}
+
+static void free_buckets(void)
+{
+       int i;
 
        for (i = 0; i < 4; ++i) {
-               node_buckets[i] = NEW_ARR_F(pbqp_node *, 0);
+               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)
@@ -50,9 +75,7 @@ static void fill_node_buckets(pbqp *pbqp)
                        arity = 3;
                }
 
-               node->bucket_index = ARR_LEN(node_buckets[arity]);
-
-               ARR_APP1(pbqp_node *, node_buckets[arity], node);
+               node_bucket_insert(&node_buckets[arity], node);
        }
 
        buckets_filled = 1;
@@ -95,10 +118,25 @@ 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 += min;
-
-                       // TODO add to edge_list if inf
+                       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);
+
+                       if (min == INF_COSTS) {
+                               unsigned edge_index;
+                               unsigned edge_len = ARR_LEN(src_node->edges);
+
+                               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);
+                                       }
+                               }
+                       }
                }
        }
 }
@@ -139,19 +177,37 @@ 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 += min;
-
-                       // TODO add to edge_list if inf
+                       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);
+
+                       if (min == INF_COSTS) {
+                               unsigned edge_index;
+                               unsigned edge_len = ARR_LEN(tgt_node->edges);
+
+                               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    arity;
+       unsigned    old_arity;
+       unsigned    old_bucket_len;
+       unsigned    old_bucket_index;
+       pbqp_node **old_bucket;
+       pbqp_node  *other;
 
        if (!buckets_filled) return;
 
@@ -159,31 +215,36 @@ static void reorder_node(pbqp_node *node)
 
        arity = ARR_LEN(node->edges);
 
-       /* Equal bucket as before */
+       /* Same bucket as before */
        if (arity > 2) return;
 
        /* Assume node lost one incident edge. */
-       old_arity = arity + 1;
+       old_arity        = arity + 1;
+       old_bucket       = node_buckets[old_arity];
+       old_bucket_len   = node_bucket_get_length(old_bucket);
+       old_bucket_index = node->bucket_index;
+
+       if (old_bucket_len <= old_bucket_index || old_bucket[old_bucket_index]
+                       != node) {
+               unsigned bucket_len = node_bucket_get_length(node_buckets[arity]);
 
-       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. */
+               assert(old_bucket_index < bucket_len);
+               assert(node_buckets[arity][old_bucket_index] == node);
                return;
        }
 
-       old_bucket_len = ARR_LEN(node_buckets[old_arity]);
-       assert (node_buckets[old_arity][node->bucket_index] == node);
+       assert(old_bucket[old_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);
+       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);
+       node->bucket_index = node_bucket_get_length(node_buckets[arity]);
+       ARR_APP1(pbqp_node*, node_buckets[arity], node);
 }
 
 static void simplify_edge(pbqp *pbqp, pbqp_edge *edge)
@@ -204,7 +265,11 @@ 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);
@@ -238,12 +303,12 @@ 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<br>\n", pbqp->dump_file);
                }
+
+               delete_edge(edge);
+               reorder_node(src_node);
+               reorder_node(tgt_node);
        }
 }
 
@@ -279,7 +344,7 @@ 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);
                }
@@ -289,14 +354,14 @@ void solve_pbqp_heuristical(pbqp *pbqp)
        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");
+               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 {
                        break;
                }
@@ -308,13 +373,14 @@ void solve_pbqp_heuristical(pbqp *pbqp)
        }
 
        /* 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 += 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);
@@ -323,12 +389,12 @@ void solve_pbqp_heuristical(pbqp *pbqp)
 
        if (pbqp->dump_file) {
                dump_section(pbqp->dump_file, 2, "Minimum");
-               fprintf(pbqp->dump_file, "Minimum is equal to %d.", pbqp->solution);
+               fprintf(pbqp->dump_file, "Minimum is equal to %lld.", pbqp->solution);
                dump_section(pbqp->dump_file, 2, "Back Propagation");
        }
 
        /* Solve reduced nodes. */
-       node_len = ARR_LEN(reduced_bucket);
+       node_len = node_bucket_get_length(reduced_bucket);
        for (node_index = node_len; node_index > 0; --node_index) {
                pbqp_node *node = reduced_bucket[node_index - 1];
                assert(node);
@@ -338,20 +404,27 @@ void solve_pbqp_heuristical(pbqp *pbqp)
                                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 apply_edge(pbqp *pbqp)
+{
+       pbqp_edge *edge = edge_bucket_pop(&edge_bucket);
+
+       simplify_edge(pbqp, edge);
 }
 
-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_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;
@@ -365,7 +438,7 @@ 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("<br>\nBefore reduction:<br>\n", pbqp->dump_file);
@@ -388,20 +461,15 @@ void applyRI(pbqp *pbqp)
                dump_node(pbqp, 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;
@@ -421,6 +489,8 @@ void applyRII(pbqp *pbqp)
        unsigned     row_len;
        unsigned     node_len;
 
+       assert(pbqp);
+
        if (src_is_src) {
                src_node = src_edge->tgt;
        } else {
@@ -450,6 +520,19 @@ 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("<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;
 
@@ -457,9 +540,9 @@ 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);
 
@@ -479,12 +562,21 @@ 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 {
@@ -492,16 +584,110 @@ 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("<br>\nAfter reduction:<br>\n", pbqp->dump_file);
+               dump_edge(pbqp, edge);
+       }
 
        /* Edge has changed so we simplify it. */
        simplify_edge(pbqp, edge);
 }
 
+void apply_RN(pbqp *pbqp)
+{
+       pbqp_node  **bucket       = node_buckets[3];
+       unsigned     bucket_len   = node_bucket_get_length(bucket);
+       unsigned     bucket_index;
+       pbqp_node   *node         = NULL;
+       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);
+
+       /* Search for node with maximum degree. */
+       for (bucket_index = 0; bucket_index < bucket_len; ++bucket_index) {
+               pbqp_node *candidate = bucket[bucket_index];
+               unsigned   degree    = ARR_LEN(candidate->edges);
+
+               if (degree > max_degree) {
+                       node = candidate;
+                       max_degree = degree;
+               }
+       }
+       assert(node);
+       node_vec = node->costs;
+       node_len = node_vec->len;
+
+       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);
+       }
+
+       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;
+               }
+       }
+
+       if (pbqp->dump_file) {
+               fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
+                                       node->index, min_index);
+               fprintf(pbqp->dump_file, "Minimal cost of RN reduction: %lld<br>\n",
+                                                       min);
+       }
+
+       node->solution = min_index;
+
+       /* Now that we found the local minimum set all other costs to infinity. */
+       for (node_index = 0; node_index < node_len; ++node_index) {
+               if (node_index != min_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]);
+       }
+}
+
 void back_propagate_RI(pbqp *pbqp, pbqp_node *node)
 {
        pbqp_edge   *edge;
@@ -534,6 +720,82 @@ 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<br>\n", node->index, node->solution);
+       }
+
+       obstack_free(&pbqp->obstack, vec);
+}
+
 int node_is_reduced(pbqp_node *node)
 {
        if (!reduced_bucket) return 0;
@@ -541,8 +803,5 @@ int node_is_reduced(pbqp_node *node)
        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;
+       return node_bucket_contains(reduced_bucket, node);
 }