nsz Git - libfirm/blob - ir/ana/vrp.c

   1 /*
   2  * Copyright (C) 1995-2009 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       analyze graph to provide value range information
  23  * @author      Jonas Fietz
  24  * @version     $Id$
  25  */
  26 #include "config.h"
  27
  28 #include "config.h"
  29 #include "irtypes.h"
  30 #include "vrp.h"
  31 #include "irouts.h"
  32 #include "irgraph_t.h"
  33 #include "irpass.h"
  34 #include "list.h"
  35 #include "irgwalk.h"
  36 #include "iredges.h"
  37 #include "tv.h"
  38 #include "irop.h"
  39
  40
  41 static char v;
  42 static void *VISITED = &v;
  43
  44 typedef struct worklist_t worklist_t;
  45 struct worklist_t {
  46          struct list_head nodes;
  47         ir_node *node;
  48 };
  49
  50 struct vrp_env_t {
  51         worklist_t *worklist;
  52 };
  53
  54 int update_vrp_data(ir_node *node)
  55 {
  56
  57         tarval *new_bits_set = get_tarval_bad();
  58         tarval *new_bits_not_set = get_tarval_bad();
  59         tarval *new_range_bottom = get_tarval_bad();
  60         tarval *new_range_top = get_tarval_bad();
  61         ir_node *new_bits_node = NULL;
  62         ir_node *new_range_node = NULL;
  63         enum range_types new_range_type = VRP_UNDEFINED;
  64         enum range_ops new_range_op = VRP_NONE;
  65         int something_changed = 0;
  66         tarval *tmp_tv, *tv;
  67         ir_node *left, *right, *pred, *bound;
  68         int overflow_top, overflow_bottom;
  69         tarval *new_top, *new_bottom;
  70
  71         pn_Cmp cmp;
  72
  73         node->vrp.valid = 1;
  74         /* TODO: Check if all predecessors have valid VRP information*/
  75
  76
  77         if (!mode_is_int(get_irn_mode(node))) {
  78                 return 0; /* we don't optimize for non-int-nodes*/
  79         }
  80
  81         switch (get_irn_opcode(node)) {
  82         case iro_Const:
  83                 tv = get_Const_tarval(node);
  84
  85                 new_bits_set = tv;
  86                 new_bits_not_set = tarval_not(tv);
  87                 new_range_bottom = tv;
  88                 new_range_top = tv;
  89                 new_range_type = VRP_RANGE;
  90                 break;
  91
  92         case iro_And:
  93                 left = get_And_left(node);
  94                 right = get_And_right(node);
  95
  96                 new_bits_set = tarval_and(left->vrp.bits_set, right->vrp.bits_set);
  97                 new_bits_not_set = tarval_or(left->vrp.bits_not_set, right->vrp.bits_not_set);
  98
  99                 tmp_tv = tarval_not(left->vrp.bits_set);
 100                 tmp_tv = tarval_eor(left->vrp.bits_not_set, tmp_tv);
 101                 /*check if one of the predecessors is completely determined*/
 102                 if (tarval_is_null(tmp_tv)) {
 103                         new_bits_node = right;
 104                 }
 105
 106                 tmp_tv = tarval_not(right->vrp.bits_set);
 107                 tmp_tv = tarval_eor(right->vrp.bits_not_set, tmp_tv);
 108                 if (tarval_is_null(tmp_tv)) {
 109                         new_bits_node = left;
 110                 }
 111                 break;
 112
 113         case iro_Add:
 114                 left = get_Add_left(node);
 115                 right = get_Add_right(node);
 116
 117
 118                 if (left->vrp.range_type == VRP_UNDEFINED || right->vrp.range_type ==
 119                                 VRP_UNDEFINED || left->vrp.range_type == VRP_VARYING ||
 120                                 right->vrp.range_type == VRP_VARYING) {
 121                         return 0;
 122                 }
 123
 124                 new_top = tarval_add(left->vrp.range_top, right->vrp.range_top);
 125                 overflow_top = tarval_carry();
 126                 new_bottom = tarval_add(left->vrp.range_bottom, right->vrp.range_bottom);
 127                 overflow_bottom = tarval_carry();
 128
 129                 if (!overflow_top && !overflow_bottom && left->vrp.range_type == VRP_RANGE
 130                                 &&right->vrp.range_type == VRP_RANGE) {
 131                         new_range_bottom = new_bottom;
 132                         new_range_top = new_top;
 133                         new_range_type = VRP_RANGE;
 134                 }
 135
 136                 if (overflow_top || overflow_bottom) {
 137                         /* TODO Implement overflow handling*/
 138                         new_range_type = VRP_UNDEFINED;
 139                 }
 140                 break;
 141
 142         case iro_Sub:
 143                 left = get_Sub_left(node);
 144                 right = get_Sub_right(node);
 145
 146                 if (left->vrp.range_type == VRP_UNDEFINED || right->vrp.range_type ==
 147                                 VRP_UNDEFINED) {
 148                         return 0;
 149                 }
 150
 151                 new_top = tarval_sub(left->vrp.range_top, right->vrp.range_top, NULL);
 152                 overflow_top = tarval_carry();
 153                 new_bottom = tarval_sub(left->vrp.range_bottom, right->vrp.range_bottom, NULL);
 154                 overflow_bottom = tarval_carry();
 155
 156                 if (!overflow_top && !overflow_bottom && left->vrp.range_type == VRP_RANGE
 157                                 &&right->vrp.range_type == VRP_RANGE) {
 158                         new_range_bottom = new_bottom;
 159                         new_range_top = new_top;
 160                         new_range_type = VRP_RANGE;
 161                 }
 162
 163                 if (overflow_top || overflow_bottom) {
 164                         /* TODO Implement overflow handling*/
 165                 }
 166                 break;
 167
 168         case iro_Or:
 169                 left = get_Or_left(node);
 170                 right = get_Or_right(node);
 171
 172                 new_bits_set = tarval_or(left->vrp.bits_set, right->vrp.bits_set);
 173                 new_bits_not_set = tarval_and(left->vrp.bits_not_set, right->vrp.bits_not_set);
 174
 175                 tmp_tv = tarval_not(left->vrp.bits_set);
 176                 tmp_tv = tarval_eor(left->vrp.bits_not_set, tmp_tv);
 177                 /*check if one of the predecessors is completely determined*/
 178                 if (tarval_is_null(tmp_tv)) {
 179                         new_bits_node = right;
 180                 }
 181
 182                 tmp_tv = tarval_not(right->vrp.bits_set);
 183                 tmp_tv = tarval_eor(right->vrp.bits_not_set, tmp_tv);
 184                 if (tarval_is_null(tmp_tv)) {
 185                         new_bits_node = left;
 186                 }
 187                 break;
 188
 189         case iro_Rotl:
 190                 left = get_Rotl_left(node);
 191                 right = get_Rotl_right(node);
 192
 193                 /* We can only compute this if the right value is a constant*/
 194                 if (is_Const(right)) {
 195                         tarval *bits_set, *bits_not_set;
 196                         bits_set = tarval_rotl(left->vrp.bits_set, get_Const_tarval(right));
 197                         bits_not_set = tarval_rotl(left->vrp.bits_not_set, get_Const_tarval(right));
 198
 199                         new_bits_set = tarval_or(bits_set, node->vrp.bits_set);
 200                         new_bits_not_set = tarval_or(bits_not_set, node->vrp.bits_not_set);
 201                 }
 202                 break;
 203
 204         case iro_Shl:
 205                 left = get_Shl_left(node);
 206                 right = get_Shl_right(node);
 207
 208                 /* We can only compute this if the right value is a constant*/
 209                 if (is_Const(right)) {
 210                         tarval *bits_set, *bits_not_set;
 211                         ir_mode *m = get_tarval_mode(node->vrp.bits_not_set);
 212                         bits_set = tarval_shl(left->vrp.bits_set, get_Const_tarval(right));
 213                         bits_not_set = tarval_shl(left->vrp.bits_not_set, get_Const_tarval(right));
 214
 215                         new_bits_set = tarval_or(bits_set, node->vrp.bits_set);
 216                         new_bits_not_set = tarval_or(bits_not_set, node->vrp.bits_not_set);
 217
 218                         bits_not_set = tarval_not( tarval_shl(
 219                                                                                 get_mode_all_one(m),
 220                                                                                 get_Const_tarval(right)));
 221                         new_bits_not_set = tarval_or(bits_not_set, new_bits_not_set);
 222
 223                 }
 224                 break;
 225
 226         case iro_Shr:
 227                 left = get_Shr_left(node);
 228                 right = get_Shr_right(node);
 229
 230                 /* We can only compute this if the right value is a constant*/
 231                 if (is_Const(right)) {
 232                         tarval *bits_set, *bits_not_set;
 233                         ir_mode *m = get_tarval_mode(node->vrp.bits_not_set);
 234                         bits_set = tarval_shr(left->vrp.bits_set, get_Const_tarval(right));
 235                         bits_not_set = tarval_shr(left->vrp.bits_not_set, get_Const_tarval(right));
 236
 237                         new_bits_set = tarval_or(bits_set, node->vrp.bits_set);
 238                         new_bits_not_set = tarval_or(bits_not_set, node->vrp.bits_not_set);
 239
 240                         bits_not_set = tarval_not( tarval_shr(
 241                                                                                 get_mode_all_one(m),
 242                                                                                 get_Const_tarval(right)));
 243                         new_bits_not_set = tarval_or(bits_not_set, new_bits_not_set);
 244                 }
 245                 break;
 246
 247         case iro_Shrs:
 248                 left = get_Shrs_left(node);
 249                 right = get_Shrs_right(node);
 250
 251                 /* We can only compute this if the right value is a constant*/
 252                 if (is_Const(right)) {
 253                         tarval *bits_set, *bits_not_set;
 254                         ir_mode *m = get_tarval_mode(node->vrp.bits_not_set);
 255                         bits_set = tarval_shrs(left->vrp.bits_set, get_Const_tarval(right));
 256                         bits_not_set = tarval_shrs(left->vrp.bits_not_set, get_Const_tarval(right));
 257
 258                         new_bits_set = tarval_or(bits_set, node->vrp.bits_set);
 259                         new_bits_not_set = tarval_or(bits_not_set, node->vrp.bits_not_set);
 260
 261                         bits_not_set = tarval_not( tarval_shrs(
 262                                                                                 get_mode_all_one(m),
 263                                                                                 get_Const_tarval(right)));
 264                         new_bits_not_set = tarval_or(bits_not_set, new_bits_not_set);
 265                 }
 266                 break;
 267
 268         case iro_Eor:
 269                 left = get_Eor_left(node);
 270                 right = get_Eor_right(node);
 271
 272                 tarval *bits_set, *bits_not_set;
 273                 bits_not_set = tarval_or(
 274                                                         tarval_and(left->vrp.bits_set, right->vrp.bits_set),
 275                                                         tarval_and(left->vrp.bits_not_set,
 276                                                                 right->vrp.bits_not_set));
 277
 278                 bits_set = tarval_or(
 279                                                 tarval_and(left->vrp.bits_set, right->vrp.bits_not_set),
 280                                                 tarval_and(left->vrp.bits_not_set, right->vrp.bits_set));
 281
 282                 new_bits_set = tarval_or(bits_set, node->vrp.bits_set);
 283                 new_bits_not_set = tarval_or(bits_not_set, node->vrp.bits_not_set);
 284                 break;
 285
 286         case iro_Id:
 287                 pred = get_Id_pred(node);
 288                 new_bits_set = pred->vrp.bits_set;
 289                 new_bits_not_set = pred->vrp.bits_not_set;
 290                 new_range_top = pred->vrp.range_top;
 291                 new_range_bottom = pred->vrp.range_bottom;
 292                 new_range_type = pred->vrp.range_type;
 293                 break;
 294
 295         case iro_Not:
 296                 pred = get_Not_op(node);
 297                 new_bits_set = tarval_or(pred->vrp.bits_not_set, node->vrp.bits_set);
 298                 new_bits_not_set = tarval_or(pred->vrp.bits_set, node->vrp.bits_not_set);
 299                 break;
 300
 301         case iro_Conv:
 302                 pred = get_Conv_op(node);
 303                 ir_mode *old_mode = get_irn_mode(pred);
 304                 ir_mode *new_mode;
 305
 306                 if (!mode_is_int(old_mode))
 307                         return 0;
 308
 309                 new_mode = get_irn_mode(node);
 310
 311                 /* The second and is needed if target type is smaller*/
 312                 bits_not_set = tarval_not(
 313                                                         tarval_convert_to(get_mode_all_one(old_mode),
 314                                                                 new_mode
 315                                                                 ));
 316                 bits_not_set = tarval_or(bits_not_set, tarval_convert_to(pred->vrp.bits_not_set, new_mode));
 317                 new_bits_not_set = tarval_or(bits_not_set, node->vrp.bits_not_set);
 318                 new_bits_set = tarval_and(
 319                                 tarval_not(bits_not_set), tarval_convert_to(pred->vrp.bits_set, new_mode));
 320
 321                 if (tarval_cmp(pred->vrp.range_top, get_mode_max(new_mode)) == pn_Cmp_Le) {
 322                         node->vrp.range_top = pred->vrp.range_top;
 323                 }
 324
 325                 if (tarval_cmp(pred->vrp.range_bottom, get_mode_min(new_mode)) == pn_Cmp_Ge) {
 326                         node->vrp.range_bottom = pred->vrp.range_bottom;
 327                 }
 328                 break;
 329
 330         case iro_Confirm:
 331                 cmp = get_Confirm_cmp(node);
 332                 bound = get_Confirm_bound(node);
 333
 334                 /** @todo: Handle non-Const bounds */
 335
 336                 if (cmp == pn_Cmp_Lg) {
 337                         /** @todo: Is there some way to preserve the information? */
 338                         new_range_type = VRP_ANTIRANGE;
 339                         if (is_Const(bound)) {
 340                                 new_range_top = get_Const_tarval(bound);
 341                                 new_range_bottom = get_Const_tarval(bound);
 342                         }
 343                 } else if (cmp == pn_Cmp_Le) {
 344                         if (node->vrp.range_type == VRP_UNDEFINED) {
 345                                 new_range_type = VRP_RANGE;
 346                                 if (is_Const(bound)) {
 347                                         new_range_top = get_Const_tarval(bound);
 348                                 }
 349                                 new_range_bottom = get_tarval_min(get_irn_mode(node));
 350                         } else if (node->vrp.range_type == VRP_RANGE) {
 351                                 if (is_Const(bound)) {
 352                                         if (tarval_cmp(node->vrp.range_top,
 353                                                                 get_Const_tarval(bound)) == pn_Cmp_Le) {
 354                                                 new_range_top = get_Const_tarval(bound);
 355                                         }
 356                                         new_range_bottom = get_tarval_min(get_irn_mode(node));
 357
 358                                 } else if (node->vrp.range_type == VRP_ANTIRANGE) {
 359                                         /** @todo: How do we manage not to get a never ending loop? */
 360                                 }
 361                         }
 362                 }
 363                 break;
 364
 365         case iro_Phi:
 366                 /* combine all ranges*/
 367
 368                 pred = get_Phi_pred(node,0);
 369                 new_range_top = pred->vrp.range_top;
 370                 new_range_bottom = pred->vrp.range_bottom;
 371                 new_range_type = pred->vrp.range_type;
 372                 new_bits_set = pred->vrp.bits_set;
 373                 new_bits_not_set = pred->vrp.bits_not_set;
 374
 375                 int num = get_Phi_n_preds(node);
 376                 pn_Cmp cmp;
 377                 int i;
 378
 379                 assert(num > 0);
 380
 381
 382                 for (i = 1; i < num; i++) {
 383                         pred = get_Phi_pred(node, i);
 384                         if (new_range_type == VRP_RANGE && pred->vrp.range_type ==
 385                                         VRP_RANGE) {
 386                                 cmp = tarval_cmp(new_range_top, pred->vrp.range_top);
 387                                 if (cmp == pn_Cmp_Lt) {
 388                                         new_range_top = pred->vrp.range_top;
 389                                 }
 390                                 cmp = tarval_cmp(new_range_bottom, pred->vrp.range_bottom);
 391                                 if (cmp == pn_Cmp_Gt) {
 392                                         new_range_bottom = pred->vrp.range_bottom;
 393                                 }
 394                         } else {
 395                                 new_range_type = VRP_VARYING;
 396                                 break;
 397                         }
 398                 }
 399
 400                 break;
 401
 402
 403         default:
 404                 /* unhandled, therefore never updated */
 405                 break;
 406         }
 407
 408
 409
 410         /* TODO: Check, if there can be information derived from any of these:
 411         is_Abs(node) is_Alloc(node) is_Anchor(node) is_Borrow(node) is_Bound(node)
 412         is_Break(node) is_Builtin(node) is_Call(node) is_CallBegin(node)
 413         is_Carry(node) is_Cast(node) is_Cmp(node) is_Cond(node)
 414         is_CopyB(node) is_Div(node) is_DivMod(node) is_Dummy(node)
 415         is_End(node) is_EndExcept(node) is_EndReg(node) is_Filter(node) is_Free(node)
 416         is_IJmp(node) is_InstOf(node) is_Jmp(node) is_Load(node) is_Minus(node)
 417         is_Mod(node) is_Mul(node) is_Mulh(node) is_Mux(node) is_NoMem(node)
 418         is_Pin(node) is_Proj(node) is_Quot(node)
 419         is_Raise(node) is_Return(node) is_Sel(node) is_Start(node) is_Store(node)
 420         is_SymConst(node) is_Sync(node) is_Tuple(node)
 421         */
 422
 423         /* Merge the newly calculated values with those that might already exist*/
 424
 425         if (new_bits_set != tarval_bad) {
 426                 new_bits_set = tarval_or(new_bits_set, node->vrp.bits_set);
 427                 if (tarval_cmp(new_bits_set, node->vrp.bits_set) != pn_Cmp_Eq) {
 428                         something_changed = 1;
 429                         node->vrp.bits_set = new_bits_set;
 430                 }
 431         }
 432
 433         if (new_bits_not_set != tarval_bad) {
 434                 new_bits_not_set = tarval_or(new_bits_not_set, node->vrp.bits_not_set);
 435
 436                 if (tarval_cmp(new_bits_not_set, node->vrp.bits_not_set) != pn_Cmp_Eq) {
 437                         something_changed = 1;
 438                         node->vrp.bits_not_set = new_bits_not_set;
 439                 }
 440         }
 441
 442         if (node->vrp.bits_node == NULL && new_bits_node != NULL) {
 443                 something_changed = 1;
 444                 node->vrp.bits_node = new_bits_node;
 445         }
 446
 447         if (node->vrp.range_type == VRP_UNDEFINED &&
 448                         new_range_type != VRP_UNDEFINED) {
 449                 something_changed = 1;
 450                 node->vrp.range_type = new_range_type;
 451                 node->vrp.range_bottom = new_range_bottom;
 452                 node->vrp.range_top = new_range_top;
 453                 node->vrp.range_op = new_range_op;
 454                 node->vrp.range_node = new_range_node;
 455
 456         } else if (node->vrp.range_type == VRP_RANGE) {
 457                 if (new_range_type == VRP_RANGE) {
 458                         if ((new_range_node == NULL && node->vrp.range_node == NULL) ||
 459                                         (new_range_node == node->vrp.range_node &&
 460                                          new_range_op == node->vrp.range_op)) {
 461                                 if (tarval_cmp(node->vrp.range_bottom, new_range_bottom) == pn_Cmp_Lt) {
 462                                         something_changed = 1;
 463                                         node->vrp.range_bottom = new_range_bottom;
 464                                 }
 465                                 if (tarval_cmp(node->vrp.range_top, new_range_top) == pn_Cmp_Gt) {
 466                                         something_changed = 1;
 467                                         node->vrp.range_top = new_range_top;
 468                                 }
 469                         }
 470
 471                         /* prefer the absolute value*/
 472                         if (new_range_node == NULL && node->vrp.range_node != NULL) {
 473                                 something_changed = 1;
 474                                 node->vrp.range_node = NULL;
 475                                 node->vrp.range_top = new_range_top;
 476                                 node->vrp.range_bottom = new_range_bottom;
 477                         }
 478                 }
 479
 480                 if (new_range_type == VRP_ANTIRANGE) {
 481                         /* if they are overlapping, cut the range.*/
 482                         /* TODO: Maybe we can preserve more information here*/
 483                         if (new_range_node == NULL && node->vrp.range_node == NULL) {
 484                                 if (tarval_cmp(node->vrp.range_bottom, new_range_top) == pn_Cmp_Gt &&
 485                                                 tarval_cmp(node->vrp.range_bottom, new_range_bottom) == pn_Cmp_Gt) {
 486                                         something_changed = 1;
 487                                         node->vrp.range_bottom = new_range_top;
 488
 489                                 } else if (tarval_cmp(node->vrp.range_top, new_range_bottom) == pn_Cmp_Gt &&
 490                                                 tarval_cmp(node->vrp.range_top, new_range_top) == pn_Cmp_Lt) {
 491                                         something_changed = 1;
 492                                         node->vrp.range_top = new_range_bottom;
 493                                 }
 494
 495                                 /* We can not handle the case where the anti range is in the*/
 496                                 /* range*/
 497                         }
 498
 499                         /* prefer the absolute value*/
 500                         if (new_range_node == NULL && node->vrp.range_node != NULL) {
 501                                 something_changed = 1;
 502                                 node->vrp.range_node = NULL;
 503                                 node->vrp.range_top = new_range_top;
 504                                 node->vrp.range_bottom = new_range_bottom;
 505                         }
 506                 }
 507         } else if (node->vrp.range_type == VRP_ANTIRANGE) {
 508                 if (new_range_type == VRP_ANTIRANGE) {
 509                         if ((new_range_node == NULL && node->vrp.range_node == NULL) ||
 510                                         (new_range_node == node->vrp.range_node &&
 511                                          new_range_op == node->vrp.range_op)) {
 512                                 if (tarval_cmp(node->vrp.range_bottom, new_range_bottom) == pn_Cmp_Gt) {
 513                                         something_changed = 1;
 514                                         node->vrp.range_bottom = new_range_bottom;
 515                                 }
 516                                 if (tarval_cmp(node->vrp.range_top, new_range_top) == pn_Cmp_Lt) {
 517                                         something_changed = 1;
 518                                         node->vrp.range_top = new_range_top;
 519                                 }
 520                         }
 521
 522                         /* prefer the absolute value*/
 523                         if (new_range_node == NULL && node->vrp.range_node != NULL) {
 524                                 something_changed = 1;
 525                                 node->vrp.range_node = NULL;
 526                                 node->vrp.range_top = new_range_top;
 527                                 node->vrp.range_bottom = new_range_bottom;
 528                         }
 529                 }
 530
 531                 if (new_range_type == VRP_RANGE) {
 532                         if ((new_range_node == NULL && node->vrp.range_node == NULL) ||
 533                                         (new_range_node == node->vrp.range_node &&
 534                                          new_range_op == node->vrp.range_op)) {
 535                                 if (tarval_cmp(node->vrp.range_bottom, new_range_top) == pn_Cmp_Gt) {
 536                                         something_changed = 1;
 537                                         node->vrp.range_bottom = new_range_top;
 538                                 }
 539                                 if (tarval_cmp(node->vrp.range_top, new_range_bottom) == pn_Cmp_Lt) {
 540                                         something_changed = 1;
 541                                         node->vrp.range_top = new_range_bottom;
 542                                 }
 543                         }
 544
 545                         /* prefer the absolute value*/
 546                         if (new_range_node == NULL && node->vrp.range_node != NULL) {
 547                                 something_changed = 1;
 548                                 node->vrp.range_node = NULL;
 549                                 node->vrp.range_top = new_range_top;
 550                                 node->vrp.range_bottom = new_range_bottom;
 551                         }
 552                 }
 553         }
 554
 555         assert(tarval_is_null(
 556                                 tarval_and(node->vrp.bits_set, node->vrp.bits_not_set)));
 557
 558         return something_changed;
 559 }
 560
 561 void vrp_first_pass(ir_node *n, void *e)
 562 {
 563         ir_node *succ;
 564         worklist_t *tmp_entry;
 565         int i;
 566         struct vrp_env_t *env = e;
 567
 568         if (is_Block(n))
 569                 return;
 570
 571         set_irn_link(n, VISITED);
 572
 573         update_vrp_data(n);
 574
 575         for (i = get_irn_n_outs(n) - 1; i >=0; --i) {
 576                 succ =  get_irn_out(n, i);
 577                 if (get_irn_link(succ) == VISITED) {
 578                         /* we found a loop*/
 579
 580                         tmp_entry = XMALLOC(worklist_t);
 581                         tmp_entry->node = n;
 582                         list_add(&(tmp_entry->nodes), &(env->worklist->nodes));
 583
 584
 585                 }
 586         }
 587 }
 588
 589
 590 void set_vrp_data(ir_graph *irg)
 591 {
 592
 593         ir_node *succ;
 594         int i;
 595         worklist_t worklist;
 596         worklist_t *tmp_entry, *tmp_entry2;
 597         struct vrp_env_t env;
 598
 599         if (!irg) {
 600                 /* no graph, skip */
 601                 return;
 602         }
 603
 604         assure_irg_outs(irg); /* ensure that out edges are consistent*/
 605
 606 /*      edges_activate(irg);*/
 607
 608         INIT_LIST_HEAD(&worklist.nodes);
 609
 610         env.worklist = &worklist;
 611         irg_walk_graph(irg, NULL, vrp_first_pass, &env);
 612
 613
 614
 615         /* while there are entries in the worklist, continue*/
 616         while ( !list_empty(&worklist.nodes) ) {
 617
 618                 list_head *pos, *next;
 619                 list_for_each_safe(pos, next, &worklist.nodes) {
 620
 621                         tmp_entry = list_entry(pos, worklist_t, nodes);
 622
 623                         if (update_vrp_data(tmp_entry->node)) {
 624                                 /* if something changed, add successors to worklist*/
 625                                 for (i = get_irn_n_outs(tmp_entry->node) - 1; i >=0; --i) {
 626                                         succ =  get_irn_out(tmp_entry->node, i);
 627
 628                                         tmp_entry2 = XMALLOC(worklist_t);
 629                                         tmp_entry2->node = succ;
 630                                         list_add(&(tmp_entry2->nodes), &worklist.nodes);
 631                                 }
 632                         }
 633
 634                         list_del(pos);
 635                         xfree(tmp_entry);
 636                 }
 637         }
 638 }
 639
 640
 641 ir_graph_pass_t *set_vrp_pass(const char *name)
 642 {
 643         return def_graph_pass(name ? name : "set_vrp", set_vrp_data);
 644 }
 645
 646 pn_Cmp vrp_cmp(ir_node *left, ir_node *right)
 647 {
 648         if (!left->vrp.valid || !right->vrp.valid) {
 649                 return pn_Cmp_False;
 650         }
 651
 652         if (left->vrp.range_type == VRP_RANGE && right->vrp.range_type == VRP_RANGE) {
 653                 if (tarval_cmp(left->vrp.range_top, right->vrp.range_bottom) == pn_Cmp_Lt) {
 654                         return pn_Cmp_Lt;
 655                 }
 656                 if (tarval_cmp(left->vrp.range_bottom, right->vrp.range_top) == pn_Cmp_Gt) {
 657                         return pn_Cmp_Gt;
 658                 }
 659         }
 660
 661         if (!tarval_is_null(tarval_and(left->vrp.bits_set, right->vrp.bits_not_set)) ||
 662                         !tarval_is_null(tarval_and(left->vrp.bits_not_set, right->vrp.bits_set))) {
 663                 return pn_Cmp_Lg;
 664         }
 665         /* TODO: We can get way more information here*/
 666
 667         return pn_Cmp_False;
 668 }