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 apply_RN_co(pbqp *pbqp, plist_t *rpeo)
  51 {
  52         pbqp_node   *node         = NULL;
  53         unsigned     min_index    = 0;
  54
  55         assert(pbqp);
  56
  57         /* We want to reduce the first node in reverse perfect elimination order. */
  58         do {
  59                 /* get first element from reverse perfect elimination order */
  60                 node = plist_first(rpeo)->data;
  61                 /* remove element from reverse perfect elimination order */
  62                 plist_erase(rpeo, plist_first(rpeo));
  63                 /* insert node at the end of rpeo so the rpeo already exits after pbqp solving */
  64                 plist_insert_back(rpeo, node);
  65         } while(node_is_reduced(node));
  66
  67         assert(node);
  68         assert(pbqp_node_get_degree(node) > 2);
  69
  70 #if     KAPS_DUMP
  71         if (pbqp->dump_file) {
  72                 char     txt[100];
  73                 sprintf(txt, "RN-Reduction of Node n%d", node->index);
  74                 dump_section(pbqp->dump_file, 2, txt);
  75                 pbqp_dump_graph(pbqp);
  76         }
  77 #endif
  78
  79         min_index = get_local_minimal_alternative(pbqp, node);
  80
  81 #if     KAPS_DUMP
  82         if (pbqp->dump_file) {
  83                 fprintf(pbqp->dump_file, "node n%d is set to %d<br><br>\n",
  84                                         node->index, min_index);
  85         }
  86 #endif
  87
  88 #if KAPS_STATISTIC
  89         if (dump == 0) {
  90                 FILE *fh = fopen("solutions.pb", "a");
  91                 fprintf(fh, "[%u]", min_index);
  92                 fclose(fh);
  93                 pbqp->num_rn++;
  94         }
  95 #endif
  96
  97         /* Now that we found the local minimum set all other costs to infinity. */
  98         select_alternative(node, min_index);
  99 }
 100
 101 static void apply_heuristic_reductions_co(pbqp *pbqp, plist_t *rpeo)
 102 {
 103         #if KAPS_TIMING
 104                 /* create timers */
 105                 ir_timer_t *t_edge = ir_timer_register("be_pbqp_edges", "pbqp reduce independent edges");
 106                 ir_timer_t *t_r0 = ir_timer_register("be_pbqp_r0", "pbqp R0 reductions");
 107                 ir_timer_t *t_r1 = ir_timer_register("be_pbqp_r1", "pbqp R1 reductions");
 108                 ir_timer_t *t_r2 = ir_timer_register("be_pbqp_r2", "pbqp R2 reductions");
 109                 ir_timer_t *t_rn = ir_timer_register("be_pbqp_rN", "pbqp RN reductions");
 110
 111                 /* reset timers */
 112                 ir_timer_reset(t_edge);
 113                 ir_timer_reset(t_r0);
 114                 ir_timer_reset(t_r1);
 115                 ir_timer_reset(t_r2);
 116                 ir_timer_reset(t_rn);
 117         #endif
 118
 119         for (;;) {
 120                 if (edge_bucket_get_length(edge_bucket) > 0) {
 121                         #if KAPS_TIMING
 122                                 ir_timer_start(t_r0);
 123                         #endif
 124
 125                         apply_edge(pbqp);
 126
 127                         #if KAPS_TIMING
 128                                 ir_timer_stop(t_r0);
 129                         #endif
 130                 } else if (node_bucket_get_length(node_buckets[1]) > 0) {
 131                         #if KAPS_TIMING
 132                                 ir_timer_start(t_r1);
 133                         #endif
 134
 135                         apply_RI(pbqp);
 136
 137                         #if KAPS_TIMING
 138                                 ir_timer_stop(t_r1);
 139                         #endif
 140                 } else if (node_bucket_get_length(node_buckets[2]) > 0) {
 141                         #if KAPS_TIMING
 142                                 ir_timer_start(t_r2);
 143                         #endif
 144
 145                         apply_RII(pbqp);
 146
 147                         #if KAPS_TIMING
 148                                 ir_timer_stop(t_r2);
 149                         #endif
 150                 } else if (node_bucket_get_length(node_buckets[3]) > 0) {
 151                         #if KAPS_TIMING
 152                                 ir_timer_start(t_rn);
 153                         #endif
 154
 155                         apply_RN_co(pbqp, rpeo);
 156
 157                         #if KAPS_TIMING
 158                                 ir_timer_stop(t_rn);
 159                         #endif
 160                 } else {
 161                         #if KAPS_TIMING
 162                                 printf("%-20s: %8.3lf msec\n", ir_timer_get_description(t_edge), (double)ir_timer_elapsed_usec(t_edge) / 1000.0);
 163                                 printf("%-20s: %8.3lf msec\n", ir_timer_get_description(t_r0), (double)ir_timer_elapsed_usec(t_r0) / 1000.0);
 164                                 printf("%-20s: %8.3lf msec\n", ir_timer_get_description(t_r1), (double)ir_timer_elapsed_usec(t_r1) / 1000.0);
 165                                 printf("%-20s: %8.3lf msec\n", ir_timer_get_description(t_r2), (double)ir_timer_elapsed_usec(t_r2) / 1000.0);
 166                                 printf("%-20s: %8.3lf msec\n", ir_timer_get_description(t_rn), (double)ir_timer_elapsed_usec(t_rn) / 1000.0);
 167                         #endif
 168
 169                         return;
 170                 }
 171         }
 172 }
 173
 174 void solve_pbqp_heuristical_co(pbqp *pbqp, plist_t *rpeo)
 175 {
 176         /* Reduce nodes degree ... */
 177         initial_simplify_edges(pbqp);
 178
 179         /* ... and put node into bucket representing their degree. */
 180         fill_node_buckets(pbqp);
 181
 182         #if KAPS_STATISTIC
 183                 FILE *fh = fopen("solutions.pb", "a");
 184                 fprintf(fh, "Solution");
 185                 fclose(fh);
 186         #endif
 187
 188         apply_heuristic_reductions_co(pbqp, rpeo);
 189
 190         pbqp->solution = determine_solution(pbqp);
 191
 192         #if KAPS_STATISTIC
 193                 fh = fopen("solutions.pb", "a");
 194                 fprintf(fh, ": %lld RE:%u R0:%u R1:%u R2:%u RN/BF:%u\n", pbqp->solution,
 195                                         pbqp->num_edges, pbqp->num_r0, pbqp->num_r1, pbqp->num_r2,
 196                                         pbqp->num_rn);
 197                 fclose(fh);
 198         #endif
 199
 200         /* Solve reduced nodes. */
 201         back_propagate(pbqp);
 202
 203         free_buckets();
 204 }