gcc/tree-affine.c

   1 /* Operations with affine combinations of trees.
   2    Copyright (C) 2005, 2007 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it
   7 under the terms of the GNU General Public License as published by the
   8 Free Software Foundation; either version 3, or (at your option) any
   9 later version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT
  12 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #include "config.h"
  21 #include "system.h"
  22 #include "coretypes.h"
  23 #include "tm.h"
  24 #include "tree.h"
  25 #include "rtl.h"
  26 #include "tm_p.h"
  27 #include "hard-reg-set.h"
  28 #include "output.h"
  29 #include "diagnostic.h"
  30 #include "tree-dump.h"
  31 #include "pointer-set.h"
  32 #include "tree-affine.h"
  33 #include "tree-gimple.h"
  34 #include "flags.h"
  35
  36 /* Extends CST as appropriate for the affine combinations COMB.  */
  37
  38 double_int
  39 double_int_ext_for_comb (double_int cst, aff_tree *comb)
  40 {
  41   return double_int_sext (cst, TYPE_PRECISION (comb->type));
  42 }
  43
  44 /* Initializes affine combination COMB so that its value is zero in TYPE.  */
  45
  46 static void
  47 aff_combination_zero (aff_tree *comb, tree type)
  48 {
  49   comb->type = type;
  50   comb->offset = double_int_zero;
  51   comb->n = 0;
  52   comb->rest = NULL_TREE;
  53 }
  54
  55 /* Sets COMB to CST.  */
  56
  57 void
  58 aff_combination_const (aff_tree *comb, tree type, double_int cst)
  59 {
  60   aff_combination_zero (comb, type);
  61   comb->offset = double_int_ext_for_comb (cst, comb);
  62 }
  63
  64 /* Sets COMB to single element ELT.  */
  65
  66 void
  67 aff_combination_elt (aff_tree *comb, tree type, tree elt)
  68 {
  69   aff_combination_zero (comb, type);
  70
  71   comb->n = 1;
  72   comb->elts[0].val = elt;
  73   comb->elts[0].coef = double_int_one;
  74 }
  75
  76 /* Scales COMB by SCALE.  */
  77
  78 void
  79 aff_combination_scale (aff_tree *comb, double_int scale)
  80 {
  81   unsigned i, j;
  82
  83   scale = double_int_ext_for_comb (scale, comb);
  84   if (double_int_one_p (scale))
  85     return;
  86
  87   if (double_int_zero_p (scale))
  88     {
  89       aff_combination_zero (comb, comb->type);
  90       return;
  91     }
  92
  93   comb->offset
  94     = double_int_ext_for_comb (double_int_mul (scale, comb->offset), comb);
  95   for (i = 0, j = 0; i < comb->n; i++)
  96     {
  97       double_int new_coef;
  98
  99       new_coef
 100         = double_int_ext_for_comb (double_int_mul (scale, comb->elts[i].coef),
 101                                    comb);
 102       /* A coefficient may become zero due to overflow.  Remove the zero
 103          elements.  */
 104       if (double_int_zero_p (new_coef))
 105         continue;
 106       comb->elts[j].coef = new_coef;
 107       comb->elts[j].val = comb->elts[i].val;
 108       j++;
 109     }
 110   comb->n = j;
 111
 112   if (comb->rest)
 113     {
 114       tree type = comb->type;
 115       if (POINTER_TYPE_P (type))
 116         type = sizetype;
 117       if (comb->n < MAX_AFF_ELTS)
 118         {
 119           comb->elts[comb->n].coef = scale;
 120           comb->elts[comb->n].val = comb->rest;
 121           comb->rest = NULL_TREE;
 122           comb->n++;
 123         }
 124       else
 125         comb->rest = fold_build2 (MULT_EXPR, type, comb->rest,
 126                                   double_int_to_tree (type, scale));
 127     }
 128 }
 129
 130 /* Adds ELT * SCALE to COMB.  */
 131
 132 void
 133 aff_combination_add_elt (aff_tree *comb, tree elt, double_int scale)
 134 {
 135   unsigned i;
 136   tree type;
 137
 138   scale = double_int_ext_for_comb (scale, comb);
 139   if (double_int_zero_p (scale))
 140     return;
 141
 142   for (i = 0; i < comb->n; i++)
 143     if (operand_equal_p (comb->elts[i].val, elt, 0))
 144       {
 145         double_int new_coef;
 146
 147         new_coef = double_int_add (comb->elts[i].coef, scale);
 148         new_coef = double_int_ext_for_comb (new_coef, comb);
 149         if (!double_int_zero_p (new_coef))
 150           {
 151             comb->elts[i].coef = new_coef;
 152             return;
 153           }
 154
 155         comb->n--;
 156         comb->elts[i] = comb->elts[comb->n];
 157
 158         if (comb->rest)
 159           {
 160             gcc_assert (comb->n == MAX_AFF_ELTS - 1);
 161             comb->elts[comb->n].coef = double_int_one;
 162             comb->elts[comb->n].val = comb->rest;
 163             comb->rest = NULL_TREE;
 164             comb->n++;
 165           }
 166         return;
 167       }
 168   if (comb->n < MAX_AFF_ELTS)
 169     {
 170       comb->elts[comb->n].coef = scale;
 171       comb->elts[comb->n].val = elt;
 172       comb->n++;
 173       return;
 174     }
 175
 176   type = comb->type;
 177   if (POINTER_TYPE_P (type))
 178     type = sizetype;
 179
 180   if (double_int_one_p (scale))
 181     elt = fold_convert (type, elt);
 182   else
 183     elt = fold_build2 (MULT_EXPR, type,
 184                        fold_convert (type, elt),
 185                        double_int_to_tree (type, scale));
 186
 187   if (comb->rest)
 188     comb->rest = fold_build2 (PLUS_EXPR, type, comb->rest,
 189                               elt);
 190   else
 191     comb->rest = elt;
 192 }
 193
 194 /* Adds CST to C.  */
 195
 196 static void
 197 aff_combination_add_cst (aff_tree *c, double_int cst)
 198 {
 199   c->offset = double_int_ext_for_comb (double_int_add (c->offset, cst), c);
 200 }
 201
 202 /* Adds COMB2 to COMB1.  */
 203
 204 void
 205 aff_combination_add (aff_tree *comb1, aff_tree *comb2)
 206 {
 207   unsigned i;
 208
 209   aff_combination_add_cst (comb1, comb2->offset);
 210   for (i = 0; i < comb2->n; i++)
 211     aff_combination_add_elt (comb1, comb2->elts[i].val, comb2->elts[i].coef);
 212   if (comb2->rest)
 213     aff_combination_add_elt (comb1, comb2->rest, double_int_one);
 214 }
 215
 216 /* Converts affine combination COMB to TYPE.  */
 217
 218 void
 219 aff_combination_convert (aff_tree *comb, tree type)
 220 {
 221   unsigned i, j;
 222   tree comb_type = comb->type;
 223
 224   if  (TYPE_PRECISION (type) > TYPE_PRECISION (comb_type))
 225     {
 226       tree val = fold_convert (type, aff_combination_to_tree (comb));
 227       tree_to_aff_combination (val, type, comb);
 228       return;
 229     }
 230
 231   comb->type = type;
 232   if (comb->rest && !POINTER_TYPE_P (type))
 233     comb->rest = fold_convert (type, comb->rest);
 234
 235   if (TYPE_PRECISION (type) == TYPE_PRECISION (comb_type))
 236     return;
 237
 238   comb->offset = double_int_ext_for_comb (comb->offset, comb);
 239   for (i = j = 0; i < comb->n; i++)
 240     {
 241       double_int new_coef = double_int_ext_for_comb (comb->elts[i].coef, comb);
 242       if (double_int_zero_p (new_coef))
 243         continue;
 244       comb->elts[j].coef = new_coef;
 245       comb->elts[j].val = fold_convert (type, comb->elts[i].val);
 246       j++;
 247     }
 248
 249   comb->n = j;
 250   if (comb->n < MAX_AFF_ELTS && comb->rest)
 251     {
 252       comb->elts[comb->n].coef = double_int_one;
 253       comb->elts[comb->n].val = comb->rest;
 254       comb->rest = NULL_TREE;
 255       comb->n++;
 256     }
 257 }
 258
 259 /* Splits EXPR into an affine combination of parts.  */
 260
 261 void
 262 tree_to_aff_combination (tree expr, tree type, aff_tree *comb)
 263 {
 264   aff_tree tmp;
 265   enum tree_code code;
 266   tree cst, core, toffset;
 267   HOST_WIDE_INT bitpos, bitsize;
 268   enum machine_mode mode;
 269   int unsignedp, volatilep;
 270
 271   STRIP_NOPS (expr);
 272
 273   code = TREE_CODE (expr);
 274   switch (code)
 275     {
 276     case INTEGER_CST:
 277       aff_combination_const (comb, type, tree_to_double_int (expr));
 278       return;
 279
 280     case POINTER_PLUS_EXPR:
 281       tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb);
 282       tree_to_aff_combination (TREE_OPERAND (expr, 1), sizetype, &tmp);
 283       aff_combination_add (comb, &tmp);
 284       return;
 285
 286     case PLUS_EXPR:
 287     case MINUS_EXPR:
 288       tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb);
 289       tree_to_aff_combination (TREE_OPERAND (expr, 1), type, &tmp);
 290       if (code == MINUS_EXPR)
 291         aff_combination_scale (&tmp, double_int_minus_one);
 292       aff_combination_add (comb, &tmp);
 293       return;
 294
 295     case MULT_EXPR:
 296       cst = TREE_OPERAND (expr, 1);
 297       if (TREE_CODE (cst) != INTEGER_CST)
 298         break;
 299       tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb);
 300       aff_combination_scale (comb, tree_to_double_int (cst));
 301       return;
 302
 303     case NEGATE_EXPR:
 304       tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb);
 305       aff_combination_scale (comb, double_int_minus_one);
 306       return;
 307
 308     case BIT_NOT_EXPR:
 309       /* ~x = -x - 1 */
 310       tree_to_aff_combination (TREE_OPERAND (expr, 0), type, comb);
 311       aff_combination_scale (comb, double_int_minus_one);
 312       aff_combination_add_cst (comb, double_int_minus_one);
 313       return;
 314
 315     case ADDR_EXPR:
 316       core = get_inner_reference (TREE_OPERAND (expr, 0), &bitsize, &bitpos,
 317                                   &toffset, &mode, &unsignedp, &volatilep,
 318                                   false);
 319       if (bitpos % BITS_PER_UNIT != 0)
 320         break;
 321       aff_combination_const (comb, type,
 322                              uhwi_to_double_int (bitpos / BITS_PER_UNIT));
 323       core = build_fold_addr_expr (core);
 324       if (TREE_CODE (core) == ADDR_EXPR)
 325         aff_combination_add_elt (comb, core, double_int_one);
 326       else
 327         {
 328           tree_to_aff_combination (core, type, &tmp);
 329           aff_combination_add (comb, &tmp);
 330         }
 331       if (toffset)
 332         {
 333           tree_to_aff_combination (toffset, type, &tmp);
 334           aff_combination_add (comb, &tmp);
 335         }
 336       return;
 337
 338     default:
 339       break;
 340     }
 341
 342   aff_combination_elt (comb, type, expr);
 343 }
 344
 345 /* Creates EXPR + ELT * SCALE in TYPE.  EXPR is taken from affine
 346    combination COMB.  */
 347
 348 static tree
 349 add_elt_to_tree (tree expr, tree type, tree elt, double_int scale,
 350                  aff_tree *comb)
 351 {
 352   enum tree_code code;
 353   tree type1 = type;
 354   if (POINTER_TYPE_P (type))
 355     type1 = sizetype;
 356
 357   scale = double_int_ext_for_comb (scale, comb);
 358   elt = fold_convert (type1, elt);
 359
 360   if (double_int_one_p (scale))
 361     {
 362       if (!expr)
 363         return fold_convert (type, elt);
 364
 365       if (POINTER_TYPE_P (type))
 366         return fold_build2 (POINTER_PLUS_EXPR, type, expr, elt);
 367       return fold_build2 (PLUS_EXPR, type, expr, elt);
 368     }
 369
 370   if (double_int_minus_one_p (scale))
 371     {
 372       if (!expr)
 373         return fold_convert (type, fold_build1 (NEGATE_EXPR, type1, elt));
 374
 375       if (POINTER_TYPE_P (type))
 376         {
 377           elt = fold_build1 (NEGATE_EXPR, type1, elt);
 378           return fold_build2 (POINTER_PLUS_EXPR, type, expr, elt);
 379         }
 380       return fold_build2 (MINUS_EXPR, type, expr, elt);
 381     }
 382
 383   if (!expr)
 384     return fold_convert (type,
 385                          fold_build2 (MULT_EXPR, type1, elt,
 386                                       double_int_to_tree (type1, scale)));
 387
 388   if (double_int_negative_p (scale))
 389     {
 390       code = MINUS_EXPR;
 391       scale = double_int_neg (scale);
 392     }
 393   else
 394     code = PLUS_EXPR;
 395
 396   elt = fold_build2 (MULT_EXPR, type1, elt,
 397                      double_int_to_tree (type1, scale));
 398   if (POINTER_TYPE_P (type))
 399     {
 400       if (code == MINUS_EXPR)
 401         elt = fold_build1 (NEGATE_EXPR, type1, elt);
 402       return fold_build2 (POINTER_PLUS_EXPR, type, expr, elt);
 403     }
 404   return fold_build2 (code, type, expr, elt);
 405 }
 406
 407 /* Makes tree from the affine combination COMB.  */
 408
 409 tree
 410 aff_combination_to_tree (aff_tree *comb)
 411 {
 412   tree type = comb->type;
 413   tree expr = comb->rest;
 414   unsigned i;
 415   double_int off, sgn;
 416   tree type1 = type;
 417   if (POINTER_TYPE_P (type))
 418     type1 = sizetype;
 419
 420   gcc_assert (comb->n == MAX_AFF_ELTS || comb->rest == NULL_TREE);
 421
 422   for (i = 0; i < comb->n; i++)
 423     expr = add_elt_to_tree (expr, type, comb->elts[i].val, comb->elts[i].coef,
 424                             comb);
 425
 426   /* Ensure that we get x - 1, not x + (-1) or x + 0xff..f if x is
 427      unsigned.  */
 428   if (double_int_negative_p (comb->offset))
 429     {
 430       off = double_int_neg (comb->offset);
 431       sgn = double_int_minus_one;
 432     }
 433   else
 434     {
 435       off = comb->offset;
 436       sgn = double_int_one;
 437     }
 438   return add_elt_to_tree (expr, type, double_int_to_tree (type1, off), sgn,
 439                           comb);
 440 }
 441
 442 /* Copies the tree elements of COMB to ensure that they are not shared.  */
 443
 444 void
 445 unshare_aff_combination (aff_tree *comb)
 446 {
 447   unsigned i;
 448
 449   for (i = 0; i < comb->n; i++)
 450     comb->elts[i].val = unshare_expr (comb->elts[i].val);
 451   if (comb->rest)
 452     comb->rest = unshare_expr (comb->rest);
 453 }
 454
 455 /* Remove M-th element from COMB.  */
 456
 457 void
 458 aff_combination_remove_elt (aff_tree *comb, unsigned m)
 459 {
 460   comb->n--;
 461   if (m <= comb->n)
 462     comb->elts[m] = comb->elts[comb->n];
 463   if (comb->rest)
 464     {
 465       comb->elts[comb->n].coef = double_int_one;
 466       comb->elts[comb->n].val = comb->rest;
 467       comb->rest = NULL_TREE;
 468       comb->n++;
 469     }
 470 }
 471
 472 /* Adds C * COEF * VAL to R.  VAL may be NULL, in that case only
 473    C * COEF is added to R.  */
 474
 475
 476 static void
 477 aff_combination_add_product (aff_tree *c, double_int coef, tree val,
 478                              aff_tree *r)
 479 {
 480   unsigned i;
 481   tree aval, type;
 482
 483   for (i = 0; i < c->n; i++)
 484     {
 485       aval = c->elts[i].val;
 486       if (val)
 487         {
 488           type = TREE_TYPE (aval);
 489           aval = fold_build2 (MULT_EXPR, type, aval,
 490                               fold_convert (type, val));
 491         }
 492
 493       aff_combination_add_elt (r, aval,
 494                                double_int_mul (coef, c->elts[i].coef));
 495     }
 496
 497   if (c->rest)
 498     {
 499       aval = c->rest;
 500       if (val)
 501         {
 502           type = TREE_TYPE (aval);
 503           aval = fold_build2 (MULT_EXPR, type, aval,
 504                               fold_convert (type, val));
 505         }
 506
 507       aff_combination_add_elt (r, aval, coef);
 508     }
 509
 510   if (val)
 511     aff_combination_add_elt (r, val,
 512                              double_int_mul (coef, c->offset));
 513   else
 514     aff_combination_add_cst (r, double_int_mul (coef, c->offset));
 515 }
 516
 517 /* Multiplies C1 by C2, storing the result to R  */
 518
 519 void
 520 aff_combination_mult (aff_tree *c1, aff_tree *c2, aff_tree *r)
 521 {
 522   unsigned i;
 523   gcc_assert (TYPE_PRECISION (c1->type) == TYPE_PRECISION (c2->type));
 524
 525   aff_combination_zero (r, c1->type);
 526
 527   for (i = 0; i < c2->n; i++)
 528     aff_combination_add_product (c1, c2->elts[i].coef, c2->elts[i].val, r);
 529   if (c2->rest)
 530     aff_combination_add_product (c1, double_int_one, c2->rest, r);
 531   aff_combination_add_product (c1, c2->offset, NULL, r);
 532 }
 533
 534 /* Returns the element of COMB whose value is VAL, or NULL if no such
 535    element exists.  If IDX is not NULL, it is set to the index of VAL in
 536    COMB.  */
 537
 538 static struct aff_comb_elt *
 539 aff_combination_find_elt (aff_tree *comb, tree val, unsigned *idx)
 540 {
 541   unsigned i;
 542
 543   for (i = 0; i < comb->n; i++)
 544     if (operand_equal_p (comb->elts[i].val, val, 0))
 545       {
 546         if (idx)
 547           *idx = i;
 548
 549         return &comb->elts[i];
 550       }
 551
 552   return NULL;
 553 }
 554
 555 /* Element of the cache that maps ssa name NAME to its expanded form
 556    as an affine expression EXPANSION.  */
 557
 558 struct name_expansion
 559 {
 560   aff_tree expansion;
 561
 562   /* True if the expansion for the name is just being generated.  */
 563   unsigned in_progress : 1;
 564 };
 565
 566 /* Expands SSA names in COMB recursively.  CACHE is used to cache the
 567    results.  */
 568
 569 void
 570 aff_combination_expand (aff_tree *comb, struct pointer_map_t **cache)
 571 {
 572   unsigned i;
 573   aff_tree to_add, current, curre;
 574   tree e, def, rhs;
 575   double_int scale;
 576   void **slot;
 577   struct name_expansion *exp;
 578
 579   aff_combination_zero (&to_add, comb->type);
 580   for (i = 0; i < comb->n; i++)
 581     {
 582       tree type, name;
 583       e = comb->elts[i].val;
 584       type = TREE_TYPE (e);
 585       name = e;
 586       /* Look through some conversions.  */
 587       if (TREE_CODE (e) == NOP_EXPR
 588           && (TYPE_PRECISION (type)
 589               >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (e, 0)))))
 590         name = TREE_OPERAND (e, 0);
 591       if (TREE_CODE (name) != SSA_NAME)
 592         continue;
 593       def = SSA_NAME_DEF_STMT (name);
 594       if (TREE_CODE (def) != GIMPLE_MODIFY_STMT
 595           || GIMPLE_STMT_OPERAND (def, 0) != name)
 596         continue;
 597
 598       rhs = GIMPLE_STMT_OPERAND (def, 1);
 599       if (TREE_CODE (rhs) != SSA_NAME
 600           && !EXPR_P (rhs)
 601           && !is_gimple_min_invariant (rhs))
 602         continue;
 603
 604       /* We do not know whether the reference retains its value at the
 605          place where the expansion is used.  */
 606       if (REFERENCE_CLASS_P (rhs))
 607         continue;
 608
 609       if (!*cache)
 610         *cache = pointer_map_create ();
 611       slot = pointer_map_insert (*cache, e);
 612       exp = *slot;
 613
 614       if (!exp)
 615         {
 616           exp = XNEW (struct name_expansion);
 617           exp->in_progress = 1;
 618           *slot = exp;
 619           if (e != name)
 620             {
 621               /* In principle this is a generally valid folding, but
 622                  it is not unconditionally an optimization, so do it
 623                  here and not in fold_unary.  */
 624               /* Convert (T1)(X *+- CST) into (T1)X *+- (T1)CST if T1 is wider
 625                  than the type of X and overflow for the type of X is
 626                  undefined.  */
 627               if (INTEGRAL_TYPE_P (type)
 628                   && INTEGRAL_TYPE_P (TREE_TYPE (rhs))
 629                   && TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (rhs))
 630                   && TYPE_PRECISION (type) > TYPE_PRECISION (TREE_TYPE (rhs))
 631                   && (TREE_CODE (rhs) == PLUS_EXPR
 632                       || TREE_CODE (rhs) == MINUS_EXPR
 633                       || TREE_CODE (rhs) == MULT_EXPR)
 634                   && TREE_CODE (TREE_OPERAND (rhs, 1)) == INTEGER_CST)
 635                 {
 636                   rhs = fold_build2 (TREE_CODE (rhs), type,
 637                                      fold_convert (type, TREE_OPERAND (rhs, 0)),
 638                                      fold_convert (type, TREE_OPERAND (rhs, 1)));
 639                 }
 640               else
 641                 rhs = fold_convert (type, rhs);
 642             }
 643           tree_to_aff_combination_expand (rhs, comb->type, &current, cache);
 644           exp->expansion = current;
 645           exp->in_progress = 0;
 646         }
 647       else
 648         {
 649           /* Since we follow the definitions in the SSA form, we should not
 650              enter a cycle unless we pass through a phi node.  */
 651           gcc_assert (!exp->in_progress);
 652           current = exp->expansion;
 653         }
 654
 655       /* Accumulate the new terms to TO_ADD, so that we do not modify
 656          COMB while traversing it; include the term -coef * E, to remove
 657          it from COMB.  */
 658       scale = comb->elts[i].coef;
 659       aff_combination_zero (&curre, comb->type);
 660       aff_combination_add_elt (&curre, e, double_int_neg (scale));
 661       aff_combination_scale (&current, scale);
 662       aff_combination_add (&to_add, &current);
 663       aff_combination_add (&to_add, &curre);
 664     }
 665   aff_combination_add (comb, &to_add);
 666 }
 667
 668 /* Similar to tree_to_aff_combination, but follows SSA name definitions
 669    and expands them recursively.  CACHE is used to cache the expansions
 670    of the ssa names, to avoid exponential time complexity for cases
 671    like
 672
 673    a1 = a0 + a0;
 674    a2 = a1 + a1;
 675    a3 = a2 + a2;
 676    ...  */
 677
 678 void
 679 tree_to_aff_combination_expand (tree expr, tree type, aff_tree *comb,
 680                                 struct pointer_map_t **cache)
 681 {
 682   tree_to_aff_combination (expr, type, comb);
 683   aff_combination_expand (comb, cache);
 684 }
 685
 686 /* Frees memory occupied by struct name_expansion in *VALUE.  Callback for
 687    pointer_map_traverse.  */
 688
 689 static bool
 690 free_name_expansion (const void *key ATTRIBUTE_UNUSED, void **value,
 691                      void *data ATTRIBUTE_UNUSED)
 692 {
 693   struct name_expansion *exp = *value;
 694
 695   free (exp);
 696   return true;
 697 }
 698
 699 /* Frees memory allocated for the CACHE used by
 700    tree_to_aff_combination_expand.  */
 701
 702 void
 703 free_affine_expand_cache (struct pointer_map_t **cache)
 704 {
 705   if (!*cache)
 706     return;
 707
 708   pointer_map_traverse (*cache, free_name_expansion, NULL);
 709   pointer_map_destroy (*cache);
 710   *cache = NULL;
 711 }
 712
 713 /* If VAL != CST * DIV for any constant CST, returns false.
 714    Otherwise, if VAL != 0 (and hence CST != 0), and *MULT_SET is true,
 715    additionally compares CST and MULT, and if they are different,
 716    returns false.  Finally, if neither of these two cases occur,
 717    true is returned, and if CST != 0, CST is stored to MULT and
 718    MULT_SET is set to true.  */
 719
 720 static bool
 721 double_int_constant_multiple_p (double_int val, double_int div,
 722                                 bool *mult_set, double_int *mult)
 723 {
 724   double_int rem, cst;
 725
 726   if (double_int_zero_p (val))
 727     return true;
 728
 729   if (double_int_zero_p (div))
 730     return false;
 731
 732   cst = double_int_sdivmod (val, div, FLOOR_DIV_EXPR, &rem);
 733   if (!double_int_zero_p (rem))
 734     return false;
 735
 736   if (*mult_set && !double_int_equal_p (*mult, cst))
 737     return false;
 738
 739   *mult_set = true;
 740   *mult = cst;
 741   return true;
 742 }
 743
 744 /* Returns true if VAL = X * DIV for some constant X.  If this is the case,
 745    X is stored to MULT.  */
 746
 747 bool
 748 aff_combination_constant_multiple_p (aff_tree *val, aff_tree *div,
 749                                      double_int *mult)
 750 {
 751   bool mult_set = false;
 752   unsigned i;
 753
 754   if (val->n == 0 && double_int_zero_p (val->offset))
 755     {
 756       *mult = double_int_zero;
 757       return true;
 758     }
 759   if (val->n != div->n)
 760     return false;
 761
 762   if (val->rest || div->rest)
 763     return false;
 764
 765   if (!double_int_constant_multiple_p (val->offset, div->offset,
 766                                        &mult_set, mult))
 767     return false;
 768
 769   for (i = 0; i < div->n; i++)
 770     {
 771       struct aff_comb_elt *elt
 772               = aff_combination_find_elt (val, div->elts[i].val, NULL);
 773       if (!elt)
 774         return false;
 775       if (!double_int_constant_multiple_p (elt->coef, div->elts[i].coef,
 776                                            &mult_set, mult))
 777         return false;
 778     }
 779
 780   gcc_assert (mult_set);
 781   return true;
 782 }
 783
 784 /* Prints the affine VAL to the FILE. */
 785
 786 void
 787 print_aff (FILE *file, aff_tree *val)
 788 {
 789   unsigned i;
 790   bool uns = TYPE_UNSIGNED (val->type);
 791   if (POINTER_TYPE_P (val->type))
 792     uns = false;
 793   fprintf (file, "{\n  type = ");
 794   print_generic_expr (file, val->type, TDF_VOPS|TDF_MEMSYMS);
 795   fprintf (file, "\n  offset = ");
 796   dump_double_int (file, val->offset, uns);
 797   if (val->n > 0)
 798     {
 799       fprintf (file, "\n  elements = {\n");
 800       for (i = 0; i < val->n; i++)
 801         {
 802           fprintf (file, "    [%d] = ", i);
 803           print_generic_expr (file, val->elts[i].val, TDF_VOPS|TDF_MEMSYMS);
 804
 805           fprintf (file, " * ");
 806           dump_double_int (file, val->elts[i].coef, uns);
 807           if (i != val->n - 1)
 808             fprintf (file, ", \n");
 809         }
 810       fprintf (file, "\n  }");
 811   }
 812   if (val->rest)
 813     {
 814       fprintf (file, "\n  rest = ");
 815       print_generic_expr (file, val->rest, TDF_VOPS|TDF_MEMSYMS);
 816     }
 817   fprintf (file, "\n}");
 818 }
 819
 820 /* Prints the affine VAL to the standard error, used for debugging.  */
 821
 822 void
 823 debug_aff (aff_tree *val)
 824 {
 825   print_aff (stderr, val);
 826   fprintf (stderr, "\n");
 827 }
 828
 829 /* Returns address of the reference REF in ADDR.  The size of the accessed
 830    location is stored to SIZE.  */
 831
 832 void
 833 get_inner_reference_aff (tree ref, aff_tree *addr, double_int *size)
 834 {
 835   HOST_WIDE_INT bitsize, bitpos;
 836   tree toff;
 837   enum machine_mode mode;
 838   int uns, vol;
 839   aff_tree tmp;
 840   tree base = get_inner_reference (ref, &bitsize, &bitpos, &toff, &mode,
 841                                    &uns, &vol, false);
 842   tree base_addr = build_fold_addr_expr (base);
 843
 844   /* ADDR = &BASE + TOFF + BITPOS / BITS_PER_UNIT.  */
 845
 846   tree_to_aff_combination (base_addr, sizetype, addr);
 847
 848   if (toff)
 849     {
 850       tree_to_aff_combination (toff, sizetype, &tmp);
 851       aff_combination_add (addr, &tmp);
 852     }
 853
 854   aff_combination_const (&tmp, sizetype,
 855                          shwi_to_double_int (bitpos / BITS_PER_UNIT));
 856   aff_combination_add (addr, &tmp);
 857
 858   *size = shwi_to_double_int ((bitsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT);
 859 }
 860