1 /* Data flow functions for trees. 2 Copyright (C) 2001-2018 Free Software Foundation, Inc. 3 Contributed by Diego Novillo <dnovillo@redhat.com> 4 5 This file is part of GCC. 6 7 GCC is free software; you can redistribute it and/or modify 8 it under the terms of the GNU General Public License as published by 9 the Free Software Foundation; either version 3, or (at your option) 10 any later version. 11 12 GCC is distributed in the hope that it will be useful, 13 but WITHOUT ANY WARRANTY; without even the implied warranty of 14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 GNU General Public License for more details. 16 17 You should have received a copy of the GNU General Public License 18 along with GCC; see the file COPYING3. If not see 19 <http://www.gnu.org/licenses/>. */ 20 21 #include "config.h" 22 #include "system.h" 23 #include "coretypes.h" 24 #include "backend.h" 25 #include "rtl.h" 26 #include "tree.h" 27 #include "gimple.h" 28 #include "tree-pass.h" 29 #include "ssa.h" 30 #include "tree-pretty-print.h" 31 #include "fold-const.h" 32 #include "stor-layout.h" 33 #include "langhooks.h" 34 #include "gimple-iterator.h" 35 #include "gimple-walk.h" 36 #include "tree-dfa.h" 37 38 /* Build and maintain data flow information for trees. */ 39 40 /* Counters used to display DFA and SSA statistics. */ 41 struct dfa_stats_d 42 { 43 long num_defs; 44 long num_uses; 45 long num_phis; 46 long num_phi_args; 47 size_t max_num_phi_args; 48 long num_vdefs; 49 long num_vuses; 50 }; 51 52 53 /* Local functions. */ 54 static void collect_dfa_stats (struct dfa_stats_d *); 55 56 57 /*--------------------------------------------------------------------------- 58 Dataflow analysis (DFA) routines 59 ---------------------------------------------------------------------------*/ 60 61 /* Renumber all of the gimple stmt uids. */ 62 63 void 64 renumber_gimple_stmt_uids (void) 65 { 66 basic_block bb; 67 68 set_gimple_stmt_max_uid (cfun, 0); 69 FOR_ALL_BB_FN (bb, cfun) 70 { 71 gimple_stmt_iterator bsi; 72 for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) 73 { 74 gimple *stmt = gsi_stmt (bsi); 75 gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun)); 76 } 77 for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) 78 { 79 gimple *stmt = gsi_stmt (bsi); 80 gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun)); 81 } 82 } 83 } 84 85 /* Like renumber_gimple_stmt_uids, but only do work on the basic blocks 86 in BLOCKS, of which there are N_BLOCKS. Also renumbers PHIs. */ 87 88 void 89 renumber_gimple_stmt_uids_in_blocks (basic_block *blocks, int n_blocks) 90 { 91 int i; 92 93 set_gimple_stmt_max_uid (cfun, 0); 94 for (i = 0; i < n_blocks; i++) 95 { 96 basic_block bb = blocks[i]; 97 gimple_stmt_iterator bsi; 98 for (bsi = gsi_start_phis (bb); !gsi_end_p (bsi); gsi_next (&bsi)) 99 { 100 gimple *stmt = gsi_stmt (bsi); 101 gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun)); 102 } 103 for (bsi = gsi_start_bb (bb); !gsi_end_p (bsi); gsi_next (&bsi)) 104 { 105 gimple *stmt = gsi_stmt (bsi); 106 gimple_set_uid (stmt, inc_gimple_stmt_max_uid (cfun)); 107 } 108 } 109 } 110 111 112 113 /*--------------------------------------------------------------------------- 114 Debugging functions 115 ---------------------------------------------------------------------------*/ 116 117 /* Dump variable VAR and its may-aliases to FILE. */ 118 119 void 120 dump_variable (FILE *file, tree var) 121 { 122 if (TREE_CODE (var) == SSA_NAME) 123 { 124 if (POINTER_TYPE_P (TREE_TYPE (var))) 125 dump_points_to_info_for (file, var); 126 var = SSA_NAME_VAR (var); 127 } 128 129 if (var == NULL_TREE) 130 { 131 fprintf (file, "<nil>"); 132 return; 133 } 134 135 print_generic_expr (file, var, dump_flags); 136 137 fprintf (file, ", UID D.%u", (unsigned) DECL_UID (var)); 138 if (DECL_PT_UID (var) != DECL_UID (var)) 139 fprintf (file, ", PT-UID D.%u", (unsigned) DECL_PT_UID (var)); 140 141 fprintf (file, ", "); 142 print_generic_expr (file, TREE_TYPE (var), dump_flags); 143 144 if (TREE_ADDRESSABLE (var)) 145 fprintf (file, ", is addressable"); 146 147 if (is_global_var (var)) 148 fprintf (file, ", is global"); 149 150 if (TREE_THIS_VOLATILE (var)) 151 fprintf (file, ", is volatile"); 152 153 if (cfun && ssa_default_def (cfun, var)) 154 { 155 fprintf (file, ", default def: "); 156 print_generic_expr (file, ssa_default_def (cfun, var), dump_flags); 157 } 158 159 if (DECL_INITIAL (var)) 160 { 161 fprintf (file, ", initial: "); 162 print_generic_expr (file, DECL_INITIAL (var), dump_flags); 163 } 164 165 fprintf (file, "\n"); 166 } 167 168 169 /* Dump variable VAR and its may-aliases to stderr. */ 170 171 DEBUG_FUNCTION void 172 debug_variable (tree var) 173 { 174 dump_variable (stderr, var); 175 } 176 177 178 /* Dump various DFA statistics to FILE. */ 179 180 void 181 dump_dfa_stats (FILE *file) 182 { 183 struct dfa_stats_d dfa_stats; 184 185 unsigned long size, total = 0; 186 const char * const fmt_str = "%-30s%-13s%12s\n"; 187 const char * const fmt_str_1 = "%-30s%13lu%11lu%c\n"; 188 const char * const fmt_str_3 = "%-43s%11lu%c\n"; 189 const char *funcname 190 = lang_hooks.decl_printable_name (current_function_decl, 2); 191 192 collect_dfa_stats (&dfa_stats); 193 194 fprintf (file, "\nDFA Statistics for %s\n\n", funcname); 195 196 fprintf (file, "---------------------------------------------------------\n"); 197 fprintf (file, fmt_str, "", " Number of ", "Memory"); 198 fprintf (file, fmt_str, "", " instances ", "used "); 199 fprintf (file, "---------------------------------------------------------\n"); 200 201 size = dfa_stats.num_uses * sizeof (tree *); 202 total += size; 203 fprintf (file, fmt_str_1, "USE operands", dfa_stats.num_uses, 204 SCALE (size), LABEL (size)); 205 206 size = dfa_stats.num_defs * sizeof (tree *); 207 total += size; 208 fprintf (file, fmt_str_1, "DEF operands", dfa_stats.num_defs, 209 SCALE (size), LABEL (size)); 210 211 size = dfa_stats.num_vuses * sizeof (tree *); 212 total += size; 213 fprintf (file, fmt_str_1, "VUSE operands", dfa_stats.num_vuses, 214 SCALE (size), LABEL (size)); 215 216 size = dfa_stats.num_vdefs * sizeof (tree *); 217 total += size; 218 fprintf (file, fmt_str_1, "VDEF operands", dfa_stats.num_vdefs, 219 SCALE (size), LABEL (size)); 220 221 size = dfa_stats.num_phis * sizeof (struct gphi); 222 total += size; 223 fprintf (file, fmt_str_1, "PHI nodes", dfa_stats.num_phis, 224 SCALE (size), LABEL (size)); 225 226 size = dfa_stats.num_phi_args * sizeof (struct phi_arg_d); 227 total += size; 228 fprintf (file, fmt_str_1, "PHI arguments", dfa_stats.num_phi_args, 229 SCALE (size), LABEL (size)); 230 231 fprintf (file, "---------------------------------------------------------\n"); 232 fprintf (file, fmt_str_3, "Total memory used by DFA/SSA data", SCALE (total), 233 LABEL (total)); 234 fprintf (file, "---------------------------------------------------------\n"); 235 fprintf (file, "\n"); 236 237 if (dfa_stats.num_phis) 238 fprintf (file, "Average number of arguments per PHI node: %.1f (max: %ld)\n", 239 (float) dfa_stats.num_phi_args / (float) dfa_stats.num_phis, 240 (long) dfa_stats.max_num_phi_args); 241 242 fprintf (file, "\n"); 243 } 244 245 246 /* Dump DFA statistics on stderr. */ 247 248 DEBUG_FUNCTION void 249 debug_dfa_stats (void) 250 { 251 dump_dfa_stats (stderr); 252 } 253 254 255 /* Collect DFA statistics and store them in the structure pointed to by 256 DFA_STATS_P. */ 257 258 static void 259 collect_dfa_stats (struct dfa_stats_d *dfa_stats_p ATTRIBUTE_UNUSED) 260 { 261 basic_block bb; 262 263 gcc_assert (dfa_stats_p); 264 265 memset ((void *)dfa_stats_p, 0, sizeof (struct dfa_stats_d)); 266 267 /* Walk all the statements in the function counting references. */ 268 FOR_EACH_BB_FN (bb, cfun) 269 { 270 for (gphi_iterator si = gsi_start_phis (bb); !gsi_end_p (si); 271 gsi_next (&si)) 272 { 273 gphi *phi = si.phi (); 274 dfa_stats_p->num_phis++; 275 dfa_stats_p->num_phi_args += gimple_phi_num_args (phi); 276 if (gimple_phi_num_args (phi) > dfa_stats_p->max_num_phi_args) 277 dfa_stats_p->max_num_phi_args = gimple_phi_num_args (phi); 278 } 279 280 for (gimple_stmt_iterator si = gsi_start_bb (bb); !gsi_end_p (si); 281 gsi_next (&si)) 282 { 283 gimple *stmt = gsi_stmt (si); 284 dfa_stats_p->num_defs += NUM_SSA_OPERANDS (stmt, SSA_OP_DEF); 285 dfa_stats_p->num_uses += NUM_SSA_OPERANDS (stmt, SSA_OP_USE); 286 dfa_stats_p->num_vdefs += gimple_vdef (stmt) ? 1 : 0; 287 dfa_stats_p->num_vuses += gimple_vuse (stmt) ? 1 : 0; 288 } 289 } 290 } 291 292 293 /*--------------------------------------------------------------------------- 294 Miscellaneous helpers 295 ---------------------------------------------------------------------------*/ 296 297 /* Lookup VAR UID in the default_defs hashtable and return the associated 298 variable. */ 299 300 tree 301 ssa_default_def (struct function *fn, tree var) 302 { 303 struct tree_decl_minimal ind; 304 struct tree_ssa_name in; 305 gcc_assert (VAR_P (var) 306 || TREE_CODE (var) == PARM_DECL 307 || TREE_CODE (var) == RESULT_DECL); 308 309 /* Always NULL_TREE for rtl function dumps. */ 310 if (!fn->gimple_df) 311 return NULL_TREE; 312 313 in.var = (tree)&ind; 314 ind.uid = DECL_UID (var); 315 return DEFAULT_DEFS (fn)->find_with_hash ((tree)&in, DECL_UID (var)); 316 } 317 318 /* Insert the pair VAR's UID, DEF into the default_defs hashtable 319 of function FN. */ 320 321 void 322 set_ssa_default_def (struct function *fn, tree var, tree def) 323 { 324 struct tree_decl_minimal ind; 325 struct tree_ssa_name in; 326 327 gcc_assert (VAR_P (var) 328 || TREE_CODE (var) == PARM_DECL 329 || TREE_CODE (var) == RESULT_DECL); 330 in.var = (tree)&ind; 331 ind.uid = DECL_UID (var); 332 if (!def) 333 { 334 tree *loc = DEFAULT_DEFS (fn)->find_slot_with_hash ((tree)&in, 335 DECL_UID (var), 336 NO_INSERT); 337 if (loc) 338 { 339 SSA_NAME_IS_DEFAULT_DEF (*(tree *)loc) = false; 340 DEFAULT_DEFS (fn)->clear_slot (loc); 341 } 342 return; 343 } 344 gcc_assert (TREE_CODE (def) == SSA_NAME && SSA_NAME_VAR (def) == var); 345 tree *loc = DEFAULT_DEFS (fn)->find_slot_with_hash ((tree)&in, 346 DECL_UID (var), INSERT); 347 348 /* Default definition might be changed by tail call optimization. */ 349 if (*loc) 350 SSA_NAME_IS_DEFAULT_DEF (*loc) = false; 351 352 /* Mark DEF as the default definition for VAR. */ 353 *loc = def; 354 SSA_NAME_IS_DEFAULT_DEF (def) = true; 355 } 356 357 /* Retrieve or create a default definition for VAR. */ 358 359 tree 360 get_or_create_ssa_default_def (struct function *fn, tree var) 361 { 362 tree ddef = ssa_default_def (fn, var); 363 if (ddef == NULL_TREE) 364 { 365 ddef = make_ssa_name_fn (fn, var, gimple_build_nop ()); 366 set_ssa_default_def (fn, var, ddef); 367 } 368 return ddef; 369 } 370 371 372 /* If EXP is a handled component reference for a structure, return the 373 base variable. The access range is delimited by bit positions *POFFSET and 374 *POFFSET + *PMAX_SIZE. The access size is *PSIZE bits. If either 375 *PSIZE or *PMAX_SIZE is -1, they could not be determined. If *PSIZE 376 and *PMAX_SIZE are equal, the access is non-variable. If *PREVERSE is 377 true, the storage order of the reference is reversed. */ 378 379 tree 380 get_ref_base_and_extent (tree exp, poly_int64_pod *poffset, 381 poly_int64_pod *psize, 382 poly_int64_pod *pmax_size, 383 bool *preverse) 384 { 385 poly_offset_int bitsize = -1; 386 poly_offset_int maxsize; 387 tree size_tree = NULL_TREE; 388 poly_offset_int bit_offset = 0; 389 bool seen_variable_array_ref = false; 390 391 /* First get the final access size and the storage order from just the 392 outermost expression. */ 393 if (TREE_CODE (exp) == COMPONENT_REF) 394 size_tree = DECL_SIZE (TREE_OPERAND (exp, 1)); 395 else if (TREE_CODE (exp) == BIT_FIELD_REF) 396 size_tree = TREE_OPERAND (exp, 1); 397 else if (!VOID_TYPE_P (TREE_TYPE (exp))) 398 { 399 machine_mode mode = TYPE_MODE (TREE_TYPE (exp)); 400 if (mode == BLKmode) 401 size_tree = TYPE_SIZE (TREE_TYPE (exp)); 402 else 403 bitsize = GET_MODE_BITSIZE (mode); 404 } 405 if (size_tree != NULL_TREE 406 && poly_int_tree_p (size_tree)) 407 bitsize = wi::to_poly_offset (size_tree); 408 409 *preverse = reverse_storage_order_for_component_p (exp); 410 411 /* Initially, maxsize is the same as the accessed element size. 412 In the following it will only grow (or become -1). */ 413 maxsize = bitsize; 414 415 /* Compute cumulative bit-offset for nested component-refs and array-refs, 416 and find the ultimate containing object. */ 417 while (1) 418 { 419 switch (TREE_CODE (exp)) 420 { 421 case BIT_FIELD_REF: 422 bit_offset += wi::to_poly_offset (TREE_OPERAND (exp, 2)); 423 break; 424 425 case COMPONENT_REF: 426 { 427 tree field = TREE_OPERAND (exp, 1); 428 tree this_offset = component_ref_field_offset (exp); 429 430 if (this_offset && poly_int_tree_p (this_offset)) 431 { 432 poly_offset_int woffset = (wi::to_poly_offset (this_offset) 433 << LOG2_BITS_PER_UNIT); 434 woffset += wi::to_offset (DECL_FIELD_BIT_OFFSET (field)); 435 bit_offset += woffset; 436 437 /* If we had seen a variable array ref already and we just 438 referenced the last field of a struct or a union member 439 then we have to adjust maxsize by the padding at the end 440 of our field. */ 441 if (seen_variable_array_ref) 442 { 443 tree stype = TREE_TYPE (TREE_OPERAND (exp, 0)); 444 tree next = DECL_CHAIN (field); 445 while (next && TREE_CODE (next) != FIELD_DECL) 446 next = DECL_CHAIN (next); 447 if (!next 448 || TREE_CODE (stype) != RECORD_TYPE) 449 { 450 tree fsize = DECL_SIZE_UNIT (field); 451 tree ssize = TYPE_SIZE_UNIT (stype); 452 if (fsize == NULL 453 || !poly_int_tree_p (fsize) 454 || ssize == NULL 455 || !poly_int_tree_p (ssize)) 456 maxsize = -1; 457 else if (known_size_p (maxsize)) 458 { 459 poly_offset_int tem 460 = (wi::to_poly_offset (ssize) 461 - wi::to_poly_offset (fsize)); 462 tem <<= LOG2_BITS_PER_UNIT; 463 tem -= woffset; 464 maxsize += tem; 465 } 466 } 467 /* An component ref with an adjacent field up in the 468 structure hierarchy constrains the size of any variable 469 array ref lower in the access hierarchy. */ 470 else 471 seen_variable_array_ref = false; 472 } 473 } 474 else 475 { 476 tree csize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0))); 477 /* We need to adjust maxsize to the whole structure bitsize. 478 But we can subtract any constant offset seen so far, 479 because that would get us out of the structure otherwise. */ 480 if (known_size_p (maxsize) 481 && csize 482 && poly_int_tree_p (csize)) 483 maxsize = wi::to_poly_offset (csize) - bit_offset; 484 else 485 maxsize = -1; 486 } 487 } 488 break; 489 490 case ARRAY_REF: 491 case ARRAY_RANGE_REF: 492 { 493 tree index = TREE_OPERAND (exp, 1); 494 tree low_bound, unit_size; 495 496 /* If the resulting bit-offset is constant, track it. */ 497 if (poly_int_tree_p (index) 498 && (low_bound = array_ref_low_bound (exp), 499 poly_int_tree_p (low_bound)) 500 && (unit_size = array_ref_element_size (exp), 501 TREE_CODE (unit_size) == INTEGER_CST)) 502 { 503 poly_offset_int woffset 504 = wi::sext (wi::to_poly_offset (index) 505 - wi::to_poly_offset (low_bound), 506 TYPE_PRECISION (TREE_TYPE (index))); 507 woffset *= wi::to_offset (unit_size); 508 woffset <<= LOG2_BITS_PER_UNIT; 509 bit_offset += woffset; 510 511 /* An array ref with a constant index up in the structure 512 hierarchy will constrain the size of any variable array ref 513 lower in the access hierarchy. */ 514 seen_variable_array_ref = false; 515 } 516 else 517 { 518 tree asize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0))); 519 /* We need to adjust maxsize to the whole array bitsize. 520 But we can subtract any constant offset seen so far, 521 because that would get us outside of the array otherwise. */ 522 if (known_size_p (maxsize) 523 && asize 524 && poly_int_tree_p (asize)) 525 maxsize = wi::to_poly_offset (asize) - bit_offset; 526 else 527 maxsize = -1; 528 529 /* Remember that we have seen an array ref with a variable 530 index. */ 531 seen_variable_array_ref = true; 532 } 533 } 534 break; 535 536 case REALPART_EXPR: 537 break; 538 539 case IMAGPART_EXPR: 540 bit_offset += bitsize; 541 break; 542 543 case VIEW_CONVERT_EXPR: 544 break; 545 546 case TARGET_MEM_REF: 547 /* Via the variable index or index2 we can reach the 548 whole object. Still hand back the decl here. */ 549 if (TREE_CODE (TMR_BASE (exp)) == ADDR_EXPR 550 && (TMR_INDEX (exp) || TMR_INDEX2 (exp))) 551 { 552 exp = TREE_OPERAND (TMR_BASE (exp), 0); 553 bit_offset = 0; 554 maxsize = -1; 555 goto done; 556 } 557 /* Fallthru. */ 558 case MEM_REF: 559 /* We need to deal with variable arrays ending structures such as 560 struct { int length; int a[1]; } x; x.a[d] 561 struct { struct { int a; int b; } a[1]; } x; x.a[d].a 562 struct { struct { int a[1]; } a[1]; } x; x.a[0][d], x.a[d][0] 563 struct { int len; union { int a[1]; struct X x; } u; } x; x.u.a[d] 564 where we do not know maxsize for variable index accesses to 565 the array. The simplest way to conservatively deal with this 566 is to punt in the case that offset + maxsize reaches the 567 base type boundary. This needs to include possible trailing 568 padding that is there for alignment purposes. */ 569 if (seen_variable_array_ref 570 && known_size_p (maxsize) 571 && (TYPE_SIZE (TREE_TYPE (exp)) == NULL_TREE 572 || !poly_int_tree_p (TYPE_SIZE (TREE_TYPE (exp))) 573 || (maybe_eq 574 (bit_offset + maxsize, 575 wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (exp))))))) 576 maxsize = -1; 577 578 /* Hand back the decl for MEM[&decl, off]. */ 579 if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR) 580 { 581 if (integer_zerop (TREE_OPERAND (exp, 1))) 582 exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); 583 else 584 { 585 poly_offset_int off = mem_ref_offset (exp); 586 off <<= LOG2_BITS_PER_UNIT; 587 off += bit_offset; 588 poly_int64 off_hwi; 589 if (off.to_shwi (&off_hwi)) 590 { 591 bit_offset = off_hwi; 592 exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); 593 } 594 } 595 } 596 goto done; 597 598 default: 599 goto done; 600 } 601 602 exp = TREE_OPERAND (exp, 0); 603 } 604 605 done: 606 if (!bitsize.to_shwi (psize) || maybe_lt (*psize, 0)) 607 { 608 *poffset = 0; 609 *psize = -1; 610 *pmax_size = -1; 611 612 return exp; 613 } 614 615 /* ??? Due to negative offsets in ARRAY_REF we can end up with 616 negative bit_offset here. We might want to store a zero offset 617 in this case. */ 618 if (!bit_offset.to_shwi (poffset)) 619 { 620 *poffset = 0; 621 *pmax_size = -1; 622 623 return exp; 624 } 625 626 /* In case of a decl or constant base object we can do better. */ 627 628 if (DECL_P (exp)) 629 { 630 if (VAR_P (exp) 631 && ((flag_unconstrained_commons && DECL_COMMON (exp)) 632 || (DECL_EXTERNAL (exp) && seen_variable_array_ref))) 633 { 634 tree sz_tree = TYPE_SIZE (TREE_TYPE (exp)); 635 /* If size is unknown, or we have read to the end, assume there 636 may be more to the structure than we are told. */ 637 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE 638 || (seen_variable_array_ref 639 && (sz_tree == NULL_TREE 640 || !poly_int_tree_p (sz_tree) 641 || maybe_eq (bit_offset + maxsize, 642 wi::to_poly_offset (sz_tree))))) 643 maxsize = -1; 644 } 645 /* If maxsize is unknown adjust it according to the size of the 646 base decl. */ 647 else if (!known_size_p (maxsize) 648 && DECL_SIZE (exp) 649 && poly_int_tree_p (DECL_SIZE (exp))) 650 maxsize = wi::to_poly_offset (DECL_SIZE (exp)) - bit_offset; 651 } 652 else if (CONSTANT_CLASS_P (exp)) 653 { 654 /* If maxsize is unknown adjust it according to the size of the 655 base type constant. */ 656 if (!known_size_p (maxsize) 657 && TYPE_SIZE (TREE_TYPE (exp)) 658 && poly_int_tree_p (TYPE_SIZE (TREE_TYPE (exp)))) 659 maxsize = (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (exp))) 660 - bit_offset); 661 } 662 663 if (!maxsize.to_shwi (pmax_size) 664 || maybe_lt (*pmax_size, 0) 665 || !endpoint_representable_p (*poffset, *pmax_size)) 666 *pmax_size = -1; 667 668 /* Punt if *POFFSET + *PSIZE overflows in HOST_WIDE_INT, the callers don't 669 check for such overflows individually and assume it works. */ 670 if (!endpoint_representable_p (*poffset, *psize)) 671 { 672 *poffset = 0; 673 *psize = -1; 674 *pmax_size = -1; 675 676 return exp; 677 } 678 679 return exp; 680 } 681 682 /* Like get_ref_base_and_extent, but for cases in which we only care 683 about constant-width accesses at constant offsets. Return null 684 if the access is anything else. */ 685 686 tree 687 get_ref_base_and_extent_hwi (tree exp, HOST_WIDE_INT *poffset, 688 HOST_WIDE_INT *psize, bool *preverse) 689 { 690 poly_int64 offset, size, max_size; 691 HOST_WIDE_INT const_offset, const_size; 692 bool reverse; 693 tree decl = get_ref_base_and_extent (exp, &offset, &size, &max_size, 694 &reverse); 695 if (!offset.is_constant (&const_offset) 696 || !size.is_constant (&const_size) 697 || const_offset < 0 698 || !known_size_p (max_size) 699 || maybe_ne (max_size, const_size)) 700 return NULL_TREE; 701 702 *poffset = const_offset; 703 *psize = const_size; 704 *preverse = reverse; 705 return decl; 706 } 707 708 /* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that 709 denotes the starting address of the memory access EXP. 710 Returns NULL_TREE if the offset is not constant or any component 711 is not BITS_PER_UNIT-aligned. 712 VALUEIZE if non-NULL is used to valueize SSA names. It should return 713 its argument or a constant if the argument is known to be constant. */ 714 715 tree 716 get_addr_base_and_unit_offset_1 (tree exp, poly_int64_pod *poffset, 717 tree (*valueize) (tree)) 718 { 719 poly_int64 byte_offset = 0; 720 721 /* Compute cumulative byte-offset for nested component-refs and array-refs, 722 and find the ultimate containing object. */ 723 while (1) 724 { 725 switch (TREE_CODE (exp)) 726 { 727 case BIT_FIELD_REF: 728 { 729 poly_int64 this_byte_offset; 730 poly_uint64 this_bit_offset; 731 if (!poly_int_tree_p (TREE_OPERAND (exp, 2), &this_bit_offset) 732 || !multiple_p (this_bit_offset, BITS_PER_UNIT, 733 &this_byte_offset)) 734 return NULL_TREE; 735 byte_offset += this_byte_offset; 736 } 737 break; 738 739 case COMPONENT_REF: 740 { 741 tree field = TREE_OPERAND (exp, 1); 742 tree this_offset = component_ref_field_offset (exp); 743 poly_int64 hthis_offset; 744 745 if (!this_offset 746 || !poly_int_tree_p (this_offset, &hthis_offset) 747 || (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) 748 % BITS_PER_UNIT)) 749 return NULL_TREE; 750 751 hthis_offset += (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) 752 / BITS_PER_UNIT); 753 byte_offset += hthis_offset; 754 } 755 break; 756 757 case ARRAY_REF: 758 case ARRAY_RANGE_REF: 759 { 760 tree index = TREE_OPERAND (exp, 1); 761 tree low_bound, unit_size; 762 763 if (valueize 764 && TREE_CODE (index) == SSA_NAME) 765 index = (*valueize) (index); 766 767 /* If the resulting bit-offset is constant, track it. */ 768 if (poly_int_tree_p (index) 769 && (low_bound = array_ref_low_bound (exp), 770 poly_int_tree_p (low_bound)) 771 && (unit_size = array_ref_element_size (exp), 772 TREE_CODE (unit_size) == INTEGER_CST)) 773 { 774 poly_offset_int woffset 775 = wi::sext (wi::to_poly_offset (index) 776 - wi::to_poly_offset (low_bound), 777 TYPE_PRECISION (TREE_TYPE (index))); 778 woffset *= wi::to_offset (unit_size); 779 byte_offset += woffset.force_shwi (); 780 } 781 else 782 return NULL_TREE; 783 } 784 break; 785 786 case REALPART_EXPR: 787 break; 788 789 case IMAGPART_EXPR: 790 byte_offset += TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (exp))); 791 break; 792 793 case VIEW_CONVERT_EXPR: 794 break; 795 796 case MEM_REF: 797 { 798 tree base = TREE_OPERAND (exp, 0); 799 if (valueize 800 && TREE_CODE (base) == SSA_NAME) 801 base = (*valueize) (base); 802 803 /* Hand back the decl for MEM[&decl, off]. */ 804 if (TREE_CODE (base) == ADDR_EXPR) 805 { 806 if (!integer_zerop (TREE_OPERAND (exp, 1))) 807 { 808 poly_offset_int off = mem_ref_offset (exp); 809 byte_offset += off.force_shwi (); 810 } 811 exp = TREE_OPERAND (base, 0); 812 } 813 goto done; 814 } 815 816 case TARGET_MEM_REF: 817 { 818 tree base = TREE_OPERAND (exp, 0); 819 if (valueize 820 && TREE_CODE (base) == SSA_NAME) 821 base = (*valueize) (base); 822 823 /* Hand back the decl for MEM[&decl, off]. */ 824 if (TREE_CODE (base) == ADDR_EXPR) 825 { 826 if (TMR_INDEX (exp) || TMR_INDEX2 (exp)) 827 return NULL_TREE; 828 if (!integer_zerop (TMR_OFFSET (exp))) 829 { 830 poly_offset_int off = mem_ref_offset (exp); 831 byte_offset += off.force_shwi (); 832 } 833 exp = TREE_OPERAND (base, 0); 834 } 835 goto done; 836 } 837 838 default: 839 goto done; 840 } 841 842 exp = TREE_OPERAND (exp, 0); 843 } 844 done: 845 846 *poffset = byte_offset; 847 return exp; 848 } 849 850 /* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that 851 denotes the starting address of the memory access EXP. 852 Returns NULL_TREE if the offset is not constant or any component 853 is not BITS_PER_UNIT-aligned. */ 854 855 tree 856 get_addr_base_and_unit_offset (tree exp, poly_int64_pod *poffset) 857 { 858 return get_addr_base_and_unit_offset_1 (exp, poffset, NULL); 859 } 860 861 /* Returns true if STMT references an SSA_NAME that has 862 SSA_NAME_OCCURS_IN_ABNORMAL_PHI set, otherwise false. */ 863 864 bool 865 stmt_references_abnormal_ssa_name (gimple *stmt) 866 { 867 ssa_op_iter oi; 868 use_operand_p use_p; 869 870 FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE) 871 { 872 if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p))) 873 return true; 874 } 875 876 return false; 877 } 878 879 /* If STMT takes any abnormal PHI values as input, replace them with 880 local copies. */ 881 882 void 883 replace_abnormal_ssa_names (gimple *stmt) 884 { 885 ssa_op_iter oi; 886 use_operand_p use_p; 887 888 FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE) 889 { 890 tree op = USE_FROM_PTR (use_p); 891 if (TREE_CODE (op) == SSA_NAME && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op)) 892 { 893 gimple_stmt_iterator gsi = gsi_for_stmt (stmt); 894 tree new_name = make_ssa_name (TREE_TYPE (op)); 895 gassign *assign = gimple_build_assign (new_name, op); 896 gsi_insert_before (&gsi, assign, GSI_SAME_STMT); 897 SET_USE (use_p, new_name); 898 } 899 } 900 } 901 902 /* Pair of tree and a sorting index, for dump_enumerated_decls. */ 903 struct GTY(()) numbered_tree 904 { 905 tree t; 906 int num; 907 }; 908 909 910 /* Compare two declarations references by their DECL_UID / sequence number. 911 Called via qsort. */ 912 913 static int 914 compare_decls_by_uid (const void *pa, const void *pb) 915 { 916 const numbered_tree *nt_a = ((const numbered_tree *)pa); 917 const numbered_tree *nt_b = ((const numbered_tree *)pb); 918 919 if (DECL_UID (nt_a->t) != DECL_UID (nt_b->t)) 920 return DECL_UID (nt_a->t) - DECL_UID (nt_b->t); 921 return nt_a->num - nt_b->num; 922 } 923 924 /* Called via walk_gimple_stmt / walk_gimple_op by dump_enumerated_decls. */ 925 static tree 926 dump_enumerated_decls_push (tree *tp, int *walk_subtrees, void *data) 927 { 928 struct walk_stmt_info *wi = (struct walk_stmt_info *) data; 929 vec<numbered_tree> *list = (vec<numbered_tree> *) wi->info; 930 numbered_tree nt; 931 932 if (!DECL_P (*tp)) 933 return NULL_TREE; 934 nt.t = *tp; 935 nt.num = list->length (); 936 list->safe_push (nt); 937 *walk_subtrees = 0; 938 return NULL_TREE; 939 } 940 941 /* Find all the declarations used by the current function, sort them by uid, 942 and emit the sorted list. Each declaration is tagged with a sequence 943 number indicating when it was found during statement / tree walking, 944 so that TDF_NOUID comparisons of anonymous declarations are still 945 meaningful. Where a declaration was encountered more than once, we 946 emit only the sequence number of the first encounter. 947 FILE is the dump file where to output the list and FLAGS is as in 948 print_generic_expr. */ 949 void 950 dump_enumerated_decls (FILE *file, dump_flags_t flags) 951 { 952 basic_block bb; 953 struct walk_stmt_info wi; 954 auto_vec<numbered_tree, 40> decl_list; 955 956 memset (&wi, '\0', sizeof (wi)); 957 wi.info = (void *) &decl_list; 958 FOR_EACH_BB_FN (bb, cfun) 959 { 960 gimple_stmt_iterator gsi; 961 962 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) 963 if (!is_gimple_debug (gsi_stmt (gsi))) 964 walk_gimple_stmt (&gsi, NULL, dump_enumerated_decls_push, &wi); 965 } 966 decl_list.qsort (compare_decls_by_uid); 967 if (decl_list.length ()) 968 { 969 unsigned ix; 970 numbered_tree *ntp; 971 tree last = NULL_TREE; 972 973 fprintf (file, "Declarations used by %s, sorted by DECL_UID:\n", 974 current_function_name ()); 975 FOR_EACH_VEC_ELT (decl_list, ix, ntp) 976 { 977 if (ntp->t == last) 978 continue; 979 fprintf (file, "%d: ", ntp->num); 980 print_generic_decl (file, ntp->t, flags); 981 fprintf (file, "\n"); 982 last = ntp->t; 983 } 984 } 985 } 986