nsz Git - libfirm/blob - heuristical_co.c

   1 /*
   2  * Copyright (C) 1995-2008 University of Karlsruhe.  All right reserved.
   3  *
   4  * This file is part of libFirm.
   5  *
   6  * This file may be distributed and/or modified under the terms of the
   7  * GNU General Public License version 2 as published by the Free Software
   8  * Foundation and appearing in the file LICENSE.GPL included in the
   9  * packaging of this file.
  10  *
  11  * Licensees holding valid libFirm Professional Edition licenses may use
  12  * this file in accordance with the libFirm Commercial License.
  13  * Agreement provided with the Software.
  14  *
  15  * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
  16  * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  17  * PURPOSE.
  18  */
  19
  20 /**
  21  * @file
  22  * @brief   Heuristic PBQP solver for SSA-based register allocation.
  23  * @date    18.09.2009
  24  * @author  Thomas Bersch
  25  * @version $Id$
  26  */
  27 #include "config.h"
  28
  29 #include "adt/array.h"
  30 #include "assert.h"
  31 #include "error.h"
  32
  33 #include "bucket.h"
  34 #include "heuristical_co.h"
  35 #include "optimal.h"
  36 #if     KAPS_DUMP
  37 #include "html_dumper.h"
  38 #endif
  39 #include "kaps.h"
  40 #include "matrix.h"
  41 #include "pbqp_edge.h"
  42 #include "pbqp_edge_t.h"
  43 #include "pbqp_node.h"
  44 #include "pbqp_node_t.h"
  45 #include "vector.h"
  46
  47 #include "plist.h"
  48 #include "timing.h"
  49
  50 static void merge_into_RN_node(pbqp *pbqp, plist_t *rpeo)
  51 {
  52         pbqp_node   *node         = NULL;
  53
  54         assert(pbqp);
  55
  56         /* We want to reduce the first node in reverse perfect elimination order. */
  57         do {
  58                 /* get first element from reverse perfect elimination order */
  59                 node = plist_first(rpeo)->data;
  60                 /* remove element from reverse perfect elimination order */
  61                 plist_erase(rpeo, plist_first(rpeo));
  62                 /* insert node at the end of rpeo so the rpeo already exits after pbqp solving */
  63                 plist_insert_back(rpeo, node);
  64         } while(node_is_reduced(node));
  65
  66         assert(node);
  67         assert(pbqp_node_get_degree(node) > 2);
  68
  69         /* Check whether we can merge a neighbor into the current node. */
  70         apply_RM(pbqp, node);
  71 }
  72
  73 static void apply_RN_co(pbqp *pbqp)
  74 {
  75         pbqp_node   *node;
  76         unsigned     min_index;
  77
  78         assert(pbqp);
  79
  80         node        = merged_node;
  81         merged_node = NULL;
  82         assert(node);
  83
  84         if (node_is_reduced(node))
  85                 return;
  86
  87 #if     KAPS_DUMP
  88         if (pbqp->dump_file) {
  89                 char     txt[100];
  90                 sprintf(txt, "RN-Reduction of Node n%d", node->index);
  91                 dump_section(pbqp->dump_file, 2, txt);
  92                 pbqp_dump_graph(pbqp);
  93         }
  94 #endif
  95
  96         min_index = get_local_minimal_alternative(pbqp, node);
  97
  98 #if     KAPS_DUMP
  99         if (pbqp->dump_file) {
 100                 fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
 101                                         node->index, min_index);
 102         }
 103 #endif
 104
 105 #if KAPS_STATISTIC
 106                 FILE *fh = fopen("solutions.pb", "a");
 107                 fprintf(fh, "[%u]", min_index);
 108                 fclose(fh);
 109                 pbqp->num_rn++;
 110 #endif
 111
 112         /* Now that we found the local minimum set all other costs to infinity. */
 113         select_alternative(node, min_index);
 114 }
 115
 116 static void apply_heuristic_reductions_co(pbqp *pbqp, plist_t *rpeo)
 117 {
 118         #if KAPS_TIMING
 119                 /* create timers */
 120                 ir_timer_t *t_edge = ir_timer_new();
 121                 ir_timer_t *t_r1   = ir_timer_new();
 122                 ir_timer_t *t_r2   = ir_timer_new();
 123                 ir_timer_t *t_rn   = ir_timer_new();
 124         #endif
 125
 126         for (;;) {
 127                 if (edge_bucket_get_length(edge_bucket) > 0) {
 128                         #if KAPS_TIMING
 129                                 ir_timer_start(t_edge);
 130                         #endif
 131
 132                         apply_edge(pbqp);
 133
 134                         #if KAPS_TIMING
 135                                 ir_timer_stop(t_edge);
 136                         #endif
 137                 } else if (node_bucket_get_length(node_buckets[1]) > 0) {
 138                         #if KAPS_TIMING
 139                                 ir_timer_start(t_r1);
 140                         #endif
 141
 142                         apply_RI(pbqp);
 143
 144                         #if KAPS_TIMING
 145                                 ir_timer_stop(t_r1);
 146                         #endif
 147                 } else if (node_bucket_get_length(node_buckets[2]) > 0) {
 148                         #if KAPS_TIMING
 149                                 ir_timer_start(t_r2);
 150                         #endif
 151
 152                         apply_RII(pbqp);
 153
 154                         #if KAPS_TIMING
 155                                 ir_timer_stop(t_r2);
 156                         #endif
 157                 } else if (merged_node != NULL) {
 158                         #if KAPS_TIMING
 159                                 ir_timer_start(t_rn);
 160                         #endif
 161
 162                         apply_RN_co(pbqp);
 163
 164                         #if KAPS_TIMING
 165                                 ir_timer_stop(t_rn);
 166                         #endif
 167                 } else if (node_bucket_get_length(node_buckets[3]) > 0) {
 168                         #if KAPS_TIMING
 169                                 ir_timer_start(t_rn);
 170                         #endif
 171
 172                         merge_into_RN_node(pbqp, rpeo);
 173
 174                         #if KAPS_TIMING
 175                                 ir_timer_stop(t_rn);
 176                         #endif
 177                 } else {
 178                         #if KAPS_TIMING
 179                                 printf("PBQP RE reductions:           %10.3lf msec\n", (double)ir_timer_elapsed_usec(t_edge) / 1000.0);
 180                                 printf("PBQP R1 reductions:           %10.3lf msec\n", (double)ir_timer_elapsed_usec(t_r1) / 1000.0);
 181                                 printf("PBQP R2 reductions:           %10.3lf msec\n", (double)ir_timer_elapsed_usec(t_r2) / 1000.0);
 182                                 printf("PBQP RN reductions:           %10.3lf msec\n", (double)ir_timer_elapsed_usec(t_rn) / 1000.0);
 183                         #endif
 184
 185                         return;
 186                 }
 187         }
 188 }
 189
 190 void solve_pbqp_heuristical_co(pbqp *pbqp, plist_t *rpeo)
 191 {
 192         /* Reduce nodes degree ... */
 193         initial_simplify_edges(pbqp);
 194
 195         /* ... and put node into bucket representing their degree. */
 196         fill_node_buckets(pbqp);
 197
 198         #if KAPS_STATISTIC
 199                 FILE *fh = fopen("solutions.pb", "a");
 200                 fprintf(fh, "Solution");
 201                 fclose(fh);
 202         #endif
 203
 204         apply_heuristic_reductions_co(pbqp, rpeo);
 205
 206         pbqp->solution = determine_solution(pbqp);
 207
 208         #if KAPS_STATISTIC
 209                 fh = fopen("solutions.pb", "a");
 210                 #if KAPS_USE_UNSIGNED
 211                         fprintf(fh, ": %u RE:%u R0:%u R1:%u R2:%u RM:%u RN/BF:%u\n", pbqp->solution,
 212                                         pbqp->num_edges, pbqp->num_r0, pbqp->num_r1, pbqp->num_r2,
 213                                         pbqp->num_rm, pbqp->num_rn);
 214                 #else
 215                         fprintf(fh, ": %lld RE:%u R0:%u R1:%u R2:%u RM:%u RN/BF:%u\n", pbqp->solution,
 216                                         pbqp->num_edges, pbqp->num_r0, pbqp->num_r1, pbqp->num_r2,
 217                 #endif
 218                 fclose(fh);
 219         #endif
 220
 221         /* Solve reduced nodes. */
 222         back_propagate(pbqp);
 223
 224         free_buckets();
 225 }