1 | /* Data flow functions for trees. |
2 | Copyright (C) 2001-2023 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 | #include "gimple-range.h" |
38 | |
39 | /* Build and maintain data flow information for trees. */ |
40 | |
41 | /* Counters used to display DFA and SSA statistics. */ |
42 | struct dfa_stats_d |
43 | { |
44 | long num_defs; |
45 | long num_uses; |
46 | long num_phis; |
47 | long num_phi_args; |
48 | size_t max_num_phi_args; |
49 | long num_vdefs; |
50 | long num_vuses; |
51 | }; |
52 | |
53 | |
54 | /* Local functions. */ |
55 | static void collect_dfa_stats (struct dfa_stats_d *); |
56 | |
57 | |
58 | /*--------------------------------------------------------------------------- |
59 | Dataflow analysis (DFA) routines |
60 | ---------------------------------------------------------------------------*/ |
61 | |
62 | /* Renumber the gimple stmt uids in one block. The caller is responsible |
63 | of calling set_gimple_stmt_max_uid (fun, 0) at some point. */ |
64 | |
65 | void |
66 | renumber_gimple_stmt_uids_in_block (struct function *fun, basic_block bb) |
67 | { |
68 | gimple_stmt_iterator bsi; |
69 | for (bsi = gsi_start_phis (bb); !gsi_end_p (i: bsi); gsi_next (i: &bsi)) |
70 | { |
71 | gimple *stmt = gsi_stmt (i: bsi); |
72 | gimple_set_uid (g: stmt, uid: inc_gimple_stmt_max_uid (fn: fun)); |
73 | } |
74 | for (bsi = gsi_start_bb (bb); !gsi_end_p (i: bsi); gsi_next (i: &bsi)) |
75 | { |
76 | gimple *stmt = gsi_stmt (i: bsi); |
77 | gimple_set_uid (g: stmt, uid: inc_gimple_stmt_max_uid (fn: fun)); |
78 | } |
79 | } |
80 | |
81 | /* Renumber all of the gimple stmt uids. */ |
82 | |
83 | void |
84 | renumber_gimple_stmt_uids (struct function *fun) |
85 | { |
86 | basic_block bb; |
87 | |
88 | set_gimple_stmt_max_uid (fn: fun, maxid: 0); |
89 | FOR_ALL_BB_FN (bb, fun) |
90 | renumber_gimple_stmt_uids_in_block (fun, bb); |
91 | } |
92 | |
93 | /* Like renumber_gimple_stmt_uids, but only do work on the basic blocks |
94 | in BLOCKS, of which there are N_BLOCKS. Also renumbers PHIs. */ |
95 | |
96 | void |
97 | renumber_gimple_stmt_uids_in_blocks (basic_block *blocks, int n_blocks) |
98 | { |
99 | int i; |
100 | |
101 | set_gimple_stmt_max_uid (cfun, maxid: 0); |
102 | for (i = 0; i < n_blocks; i++) |
103 | renumber_gimple_stmt_uids_in_block (cfun, bb: blocks[i]); |
104 | } |
105 | |
106 | |
107 | |
108 | /*--------------------------------------------------------------------------- |
109 | Debugging functions |
110 | ---------------------------------------------------------------------------*/ |
111 | |
112 | /* Dump variable VAR and its may-aliases to FILE. */ |
113 | |
114 | void |
115 | dump_variable (FILE *file, tree var) |
116 | { |
117 | if (TREE_CODE (var) == SSA_NAME) |
118 | { |
119 | if (POINTER_TYPE_P (TREE_TYPE (var))) |
120 | dump_points_to_info_for (file, var); |
121 | var = SSA_NAME_VAR (var); |
122 | } |
123 | |
124 | if (var == NULL_TREE) |
125 | { |
126 | fprintf (stream: file, format: "<nil>" ); |
127 | return; |
128 | } |
129 | |
130 | print_generic_expr (file, var, dump_flags); |
131 | |
132 | fprintf (stream: file, format: ", UID D.%u" , (unsigned) DECL_UID (var)); |
133 | if (DECL_PT_UID (var) != DECL_UID (var)) |
134 | fprintf (stream: file, format: ", PT-UID D.%u" , (unsigned) DECL_PT_UID (var)); |
135 | |
136 | fprintf (stream: file, format: ", " ); |
137 | print_generic_expr (file, TREE_TYPE (var), dump_flags); |
138 | |
139 | if (TREE_ADDRESSABLE (var)) |
140 | fprintf (stream: file, format: ", is addressable" ); |
141 | |
142 | if (is_global_var (t: var)) |
143 | fprintf (stream: file, format: ", is global" ); |
144 | |
145 | if (TREE_THIS_VOLATILE (var)) |
146 | fprintf (stream: file, format: ", is volatile" ); |
147 | |
148 | if (cfun && ssa_default_def (cfun, var)) |
149 | { |
150 | fprintf (stream: file, format: ", default def: " ); |
151 | print_generic_expr (file, ssa_default_def (cfun, var), dump_flags); |
152 | } |
153 | |
154 | if (DECL_INITIAL (var)) |
155 | { |
156 | fprintf (stream: file, format: ", initial: " ); |
157 | print_generic_expr (file, DECL_INITIAL (var), dump_flags); |
158 | } |
159 | |
160 | fprintf (stream: file, format: "\n" ); |
161 | } |
162 | |
163 | |
164 | /* Dump variable VAR and its may-aliases to stderr. */ |
165 | |
166 | DEBUG_FUNCTION void |
167 | debug_variable (tree var) |
168 | { |
169 | dump_variable (stderr, var); |
170 | } |
171 | |
172 | |
173 | /* Dump various DFA statistics to FILE. */ |
174 | |
175 | void |
176 | dump_dfa_stats (FILE *file) |
177 | { |
178 | struct dfa_stats_d dfa_stats; |
179 | |
180 | unsigned long size, total = 0; |
181 | const char * const fmt_str = "%-30s%-13s%12s\n" ; |
182 | const char * const fmt_str_1 = "%-30s%13lu" PRsa (11) "\n" ; |
183 | const char * const fmt_str_3 = "%-43s" PRsa (11) "\n" ; |
184 | const char *funcname |
185 | = lang_hooks.decl_printable_name (current_function_decl, 2); |
186 | |
187 | collect_dfa_stats (&dfa_stats); |
188 | |
189 | fprintf (stream: file, format: "\nDFA Statistics for %s\n\n" , funcname); |
190 | |
191 | fprintf (stream: file, format: "---------------------------------------------------------\n" ); |
192 | fprintf (stream: file, format: fmt_str, "" , " Number of " , "Memory" ); |
193 | fprintf (stream: file, format: fmt_str, "" , " instances " , "used " ); |
194 | fprintf (stream: file, format: "---------------------------------------------------------\n" ); |
195 | |
196 | size = dfa_stats.num_uses * sizeof (tree *); |
197 | total += size; |
198 | fprintf (stream: file, format: fmt_str_1, "USE operands" , dfa_stats.num_uses, |
199 | SIZE_AMOUNT (size)); |
200 | |
201 | size = dfa_stats.num_defs * sizeof (tree *); |
202 | total += size; |
203 | fprintf (stream: file, format: fmt_str_1, "DEF operands" , dfa_stats.num_defs, |
204 | SIZE_AMOUNT (size)); |
205 | |
206 | size = dfa_stats.num_vuses * sizeof (tree *); |
207 | total += size; |
208 | fprintf (stream: file, format: fmt_str_1, "VUSE operands" , dfa_stats.num_vuses, |
209 | SIZE_AMOUNT (size)); |
210 | |
211 | size = dfa_stats.num_vdefs * sizeof (tree *); |
212 | total += size; |
213 | fprintf (stream: file, format: fmt_str_1, "VDEF operands" , dfa_stats.num_vdefs, |
214 | SIZE_AMOUNT (size)); |
215 | |
216 | size = dfa_stats.num_phis * sizeof (struct gphi); |
217 | total += size; |
218 | fprintf (stream: file, format: fmt_str_1, "PHI nodes" , dfa_stats.num_phis, |
219 | SIZE_AMOUNT (size)); |
220 | |
221 | size = dfa_stats.num_phi_args * sizeof (struct phi_arg_d); |
222 | total += size; |
223 | fprintf (stream: file, format: fmt_str_1, "PHI arguments" , dfa_stats.num_phi_args, |
224 | SIZE_AMOUNT (size)); |
225 | |
226 | fprintf (stream: file, format: "---------------------------------------------------------\n" ); |
227 | fprintf (stream: file, format: fmt_str_3, "Total memory used by DFA/SSA data" , |
228 | SIZE_AMOUNT (total)); |
229 | fprintf (stream: file, format: "---------------------------------------------------------\n" ); |
230 | fprintf (stream: file, format: "\n" ); |
231 | |
232 | if (dfa_stats.num_phis) |
233 | fprintf (stream: file, format: "Average number of arguments per PHI node: %.1f (max: %ld)\n" , |
234 | (float) dfa_stats.num_phi_args / (float) dfa_stats.num_phis, |
235 | (long) dfa_stats.max_num_phi_args); |
236 | |
237 | fprintf (stream: file, format: "\n" ); |
238 | } |
239 | |
240 | |
241 | /* Dump DFA statistics on stderr. */ |
242 | |
243 | DEBUG_FUNCTION void |
244 | debug_dfa_stats (void) |
245 | { |
246 | dump_dfa_stats (stderr); |
247 | } |
248 | |
249 | |
250 | /* Collect DFA statistics and store them in the structure pointed to by |
251 | DFA_STATS_P. */ |
252 | |
253 | static void |
254 | collect_dfa_stats (struct dfa_stats_d *dfa_stats_p ATTRIBUTE_UNUSED) |
255 | { |
256 | basic_block bb; |
257 | |
258 | gcc_assert (dfa_stats_p); |
259 | |
260 | memset (s: (void *)dfa_stats_p, c: 0, n: sizeof (struct dfa_stats_d)); |
261 | |
262 | /* Walk all the statements in the function counting references. */ |
263 | FOR_EACH_BB_FN (bb, cfun) |
264 | { |
265 | for (gphi_iterator si = gsi_start_phis (bb); !gsi_end_p (i: si); |
266 | gsi_next (i: &si)) |
267 | { |
268 | gphi *phi = si.phi (); |
269 | dfa_stats_p->num_phis++; |
270 | dfa_stats_p->num_phi_args += gimple_phi_num_args (gs: phi); |
271 | if (gimple_phi_num_args (gs: phi) > dfa_stats_p->max_num_phi_args) |
272 | dfa_stats_p->max_num_phi_args = gimple_phi_num_args (gs: phi); |
273 | } |
274 | |
275 | for (gimple_stmt_iterator si = gsi_start_bb (bb); !gsi_end_p (i: si); |
276 | gsi_next (i: &si)) |
277 | { |
278 | gimple *stmt = gsi_stmt (i: si); |
279 | dfa_stats_p->num_defs += NUM_SSA_OPERANDS (stmt, SSA_OP_DEF); |
280 | dfa_stats_p->num_uses += NUM_SSA_OPERANDS (stmt, SSA_OP_USE); |
281 | dfa_stats_p->num_vdefs += gimple_vdef (g: stmt) ? 1 : 0; |
282 | dfa_stats_p->num_vuses += gimple_vuse (g: stmt) ? 1 : 0; |
283 | } |
284 | } |
285 | } |
286 | |
287 | |
288 | /*--------------------------------------------------------------------------- |
289 | Miscellaneous helpers |
290 | ---------------------------------------------------------------------------*/ |
291 | |
292 | /* Lookup VAR UID in the default_defs hashtable and return the associated |
293 | variable. */ |
294 | |
295 | tree |
296 | ssa_default_def (struct function *fn, tree var) |
297 | { |
298 | struct tree_decl_minimal ind; |
299 | struct tree_ssa_name in; |
300 | gcc_assert (VAR_P (var) |
301 | || TREE_CODE (var) == PARM_DECL |
302 | || TREE_CODE (var) == RESULT_DECL); |
303 | |
304 | /* Always NULL_TREE for rtl function dumps. */ |
305 | if (!fn->gimple_df) |
306 | return NULL_TREE; |
307 | |
308 | in.var = (tree)&ind; |
309 | ind.uid = DECL_UID (var); |
310 | return DEFAULT_DEFS (fn)->find_with_hash (comparable: (tree)&in, DECL_UID (var)); |
311 | } |
312 | |
313 | /* Insert the pair VAR's UID, DEF into the default_defs hashtable |
314 | of function FN. */ |
315 | |
316 | void |
317 | set_ssa_default_def (struct function *fn, tree var, tree def) |
318 | { |
319 | struct tree_decl_minimal ind; |
320 | struct tree_ssa_name in; |
321 | |
322 | gcc_assert (VAR_P (var) |
323 | || TREE_CODE (var) == PARM_DECL |
324 | || TREE_CODE (var) == RESULT_DECL); |
325 | in.var = (tree)&ind; |
326 | ind.uid = DECL_UID (var); |
327 | if (!def) |
328 | { |
329 | tree *loc = DEFAULT_DEFS (fn)->find_slot_with_hash (comparable: (tree)&in, |
330 | DECL_UID (var), |
331 | insert: NO_INSERT); |
332 | if (loc) |
333 | { |
334 | SSA_NAME_IS_DEFAULT_DEF (*(tree *)loc) = false; |
335 | DEFAULT_DEFS (fn)->clear_slot (slot: loc); |
336 | } |
337 | return; |
338 | } |
339 | gcc_assert (TREE_CODE (def) == SSA_NAME && SSA_NAME_VAR (def) == var); |
340 | tree *loc = DEFAULT_DEFS (fn)->find_slot_with_hash (comparable: (tree)&in, |
341 | DECL_UID (var), insert: INSERT); |
342 | |
343 | /* Default definition might be changed by tail call optimization. */ |
344 | if (*loc) |
345 | SSA_NAME_IS_DEFAULT_DEF (*loc) = false; |
346 | |
347 | /* Mark DEF as the default definition for VAR. */ |
348 | *loc = def; |
349 | SSA_NAME_IS_DEFAULT_DEF (def) = true; |
350 | } |
351 | |
352 | /* Retrieve or create a default definition for VAR. */ |
353 | |
354 | tree |
355 | get_or_create_ssa_default_def (struct function *fn, tree var) |
356 | { |
357 | tree ddef = ssa_default_def (fn, var); |
358 | if (ddef == NULL_TREE) |
359 | { |
360 | ddef = make_ssa_name_fn (fn, var, gimple_build_nop ()); |
361 | set_ssa_default_def (fn, var, def: ddef); |
362 | } |
363 | return ddef; |
364 | } |
365 | |
366 | |
367 | /* If EXP is a handled component reference for a structure, return the |
368 | base variable. The access range is delimited by bit positions *POFFSET and |
369 | *POFFSET + *PMAX_SIZE. The access size is *PSIZE bits. If either |
370 | *PSIZE or *PMAX_SIZE is -1, they could not be determined. If *PSIZE |
371 | and *PMAX_SIZE are equal, the access is non-variable. If *PREVERSE is |
372 | true, the storage order of the reference is reversed. */ |
373 | |
374 | tree |
375 | get_ref_base_and_extent (tree exp, poly_int64 *poffset, |
376 | poly_int64 *psize, |
377 | poly_int64 *pmax_size, |
378 | bool *preverse) |
379 | { |
380 | poly_offset_int bitsize = -1; |
381 | poly_offset_int maxsize; |
382 | tree size_tree = NULL_TREE; |
383 | poly_offset_int bit_offset = 0; |
384 | bool seen_variable_array_ref = false; |
385 | |
386 | /* First get the final access size and the storage order from just the |
387 | outermost expression. */ |
388 | if (TREE_CODE (exp) == COMPONENT_REF) |
389 | size_tree = DECL_SIZE (TREE_OPERAND (exp, 1)); |
390 | else if (TREE_CODE (exp) == BIT_FIELD_REF) |
391 | size_tree = TREE_OPERAND (exp, 1); |
392 | else if (TREE_CODE (exp) == WITH_SIZE_EXPR) |
393 | { |
394 | size_tree = TREE_OPERAND (exp, 1); |
395 | exp = TREE_OPERAND (exp, 0); |
396 | } |
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 (t: size_tree)) |
407 | bitsize = wi::to_poly_offset (t: size_tree); |
408 | |
409 | *preverse = reverse_storage_order_for_component_p (t: 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 (t: this_offset)) |
431 | { |
432 | poly_offset_int woffset = (wi::to_poly_offset (t: 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 (field); |
451 | tree ssize = TYPE_SIZE (stype); |
452 | if (fsize == NULL |
453 | || !poly_int_tree_p (t: fsize) |
454 | || ssize == NULL |
455 | || !poly_int_tree_p (t: ssize)) |
456 | maxsize = -1; |
457 | else if (known_size_p (a: maxsize)) |
458 | { |
459 | poly_offset_int tem |
460 | = (wi::to_poly_offset (t: ssize) |
461 | - wi::to_poly_offset (t: fsize)); |
462 | tem -= woffset; |
463 | maxsize += tem; |
464 | } |
465 | } |
466 | /* An component ref with an adjacent field up in the |
467 | structure hierarchy constrains the size of any variable |
468 | array ref lower in the access hierarchy. */ |
469 | else |
470 | seen_variable_array_ref = false; |
471 | } |
472 | } |
473 | else |
474 | { |
475 | tree csize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
476 | /* We need to adjust maxsize to the whole structure bitsize. |
477 | But we can subtract any constant offset seen so far, |
478 | because that would get us out of the structure otherwise. */ |
479 | if (known_size_p (a: maxsize) |
480 | && csize |
481 | && poly_int_tree_p (t: csize)) |
482 | maxsize = wi::to_poly_offset (t: csize) - bit_offset; |
483 | else |
484 | maxsize = -1; |
485 | } |
486 | } |
487 | break; |
488 | |
489 | case ARRAY_REF: |
490 | case ARRAY_RANGE_REF: |
491 | { |
492 | tree index = TREE_OPERAND (exp, 1); |
493 | tree low_bound, unit_size; |
494 | |
495 | /* If the resulting bit-offset is constant, track it. */ |
496 | if (poly_int_tree_p (t: index) |
497 | && (low_bound = array_ref_low_bound (exp), |
498 | poly_int_tree_p (t: low_bound)) |
499 | && (unit_size = array_ref_element_size (exp), |
500 | TREE_CODE (unit_size) == INTEGER_CST)) |
501 | { |
502 | poly_offset_int woffset |
503 | = wi::sext (a: wi::to_poly_offset (t: index) |
504 | - wi::to_poly_offset (t: low_bound), |
505 | TYPE_PRECISION (sizetype)); |
506 | woffset *= wi::to_offset (t: unit_size); |
507 | woffset <<= LOG2_BITS_PER_UNIT; |
508 | bit_offset += woffset; |
509 | |
510 | /* An array ref with a constant index up in the structure |
511 | hierarchy will constrain the size of any variable array ref |
512 | lower in the access hierarchy. */ |
513 | seen_variable_array_ref = false; |
514 | } |
515 | else |
516 | { |
517 | tree asize = TYPE_SIZE (TREE_TYPE (TREE_OPERAND (exp, 0))); |
518 | /* We need to adjust maxsize to the whole array bitsize. |
519 | But we can subtract any constant offset seen so far, |
520 | because that would get us outside of the array otherwise. */ |
521 | if (known_size_p (a: maxsize) |
522 | && asize |
523 | && poly_int_tree_p (t: asize)) |
524 | maxsize = wi::to_poly_offset (t: asize) - bit_offset; |
525 | else |
526 | maxsize = -1; |
527 | |
528 | /* Remember that we have seen an array ref with a variable |
529 | index. */ |
530 | seen_variable_array_ref = true; |
531 | |
532 | value_range vr; |
533 | range_query *query; |
534 | query = get_range_query (cfun); |
535 | |
536 | if (TREE_CODE (index) == SSA_NAME |
537 | && (low_bound = array_ref_low_bound (exp), |
538 | poly_int_tree_p (t: low_bound)) |
539 | && (unit_size = array_ref_element_size (exp), |
540 | TREE_CODE (unit_size) == INTEGER_CST) |
541 | && query->range_of_expr (r&: vr, expr: index) |
542 | && !vr.varying_p () |
543 | && !vr.undefined_p ()) |
544 | { |
545 | wide_int min = vr.lower_bound (); |
546 | wide_int max = vr.upper_bound (); |
547 | poly_offset_int lbound = wi::to_poly_offset (t: low_bound); |
548 | /* Try to constrain maxsize with range information. */ |
549 | offset_int omax |
550 | = offset_int::from (x: max, TYPE_SIGN (TREE_TYPE (index))); |
551 | if (known_lt (lbound, omax)) |
552 | { |
553 | poly_offset_int rmaxsize; |
554 | rmaxsize = (omax - lbound + 1) |
555 | * wi::to_offset (t: unit_size) << LOG2_BITS_PER_UNIT; |
556 | if (!known_size_p (a: maxsize) |
557 | || known_lt (rmaxsize, maxsize)) |
558 | { |
559 | /* If we know an upper bound below the declared |
560 | one this is no longer variable. */ |
561 | if (known_size_p (a: maxsize)) |
562 | seen_variable_array_ref = false; |
563 | maxsize = rmaxsize; |
564 | } |
565 | } |
566 | /* Try to adjust bit_offset with range information. */ |
567 | offset_int omin |
568 | = offset_int::from (x: min, TYPE_SIGN (TREE_TYPE (index))); |
569 | if (known_le (lbound, omin)) |
570 | { |
571 | poly_offset_int woffset |
572 | = wi::sext (a: omin - lbound, |
573 | TYPE_PRECISION (sizetype)); |
574 | woffset *= wi::to_offset (t: unit_size); |
575 | woffset <<= LOG2_BITS_PER_UNIT; |
576 | bit_offset += woffset; |
577 | if (known_size_p (a: maxsize)) |
578 | maxsize -= woffset; |
579 | } |
580 | } |
581 | } |
582 | } |
583 | break; |
584 | |
585 | case REALPART_EXPR: |
586 | break; |
587 | |
588 | case IMAGPART_EXPR: |
589 | bit_offset += bitsize; |
590 | break; |
591 | |
592 | case VIEW_CONVERT_EXPR: |
593 | break; |
594 | |
595 | case TARGET_MEM_REF: |
596 | /* Via the variable index or index2 we can reach the |
597 | whole object. Still hand back the decl here. */ |
598 | if (TREE_CODE (TMR_BASE (exp)) == ADDR_EXPR |
599 | && (TMR_INDEX (exp) || TMR_INDEX2 (exp))) |
600 | { |
601 | exp = TREE_OPERAND (TMR_BASE (exp), 0); |
602 | bit_offset = 0; |
603 | maxsize = -1; |
604 | goto done; |
605 | } |
606 | /* Fallthru. */ |
607 | case MEM_REF: |
608 | /* We need to deal with variable arrays ending structures such as |
609 | struct { int length; int a[1]; } x; x.a[d] |
610 | struct { struct { int a; int b; } a[1]; } x; x.a[d].a |
611 | struct { struct { int a[1]; } a[1]; } x; x.a[0][d], x.a[d][0] |
612 | struct { int len; union { int a[1]; struct X x; } u; } x; x.u.a[d] |
613 | where we do not know maxsize for variable index accesses to |
614 | the array. The simplest way to conservatively deal with this |
615 | is to punt in the case that offset + maxsize reaches the |
616 | base type boundary. This needs to include possible trailing |
617 | padding that is there for alignment purposes. */ |
618 | if (seen_variable_array_ref |
619 | && known_size_p (a: maxsize) |
620 | && (TYPE_SIZE (TREE_TYPE (exp)) == NULL_TREE |
621 | || !poly_int_tree_p (TYPE_SIZE (TREE_TYPE (exp))) |
622 | || (maybe_eq |
623 | (a: bit_offset + maxsize, |
624 | b: wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (exp))))))) |
625 | maxsize = -1; |
626 | |
627 | /* Hand back the decl for MEM[&decl, off]. */ |
628 | if (TREE_CODE (TREE_OPERAND (exp, 0)) == ADDR_EXPR) |
629 | { |
630 | if (integer_zerop (TREE_OPERAND (exp, 1))) |
631 | exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); |
632 | else |
633 | { |
634 | poly_offset_int off = mem_ref_offset (exp); |
635 | off <<= LOG2_BITS_PER_UNIT; |
636 | off += bit_offset; |
637 | poly_int64 off_hwi; |
638 | if (off.to_shwi (r: &off_hwi)) |
639 | { |
640 | bit_offset = off_hwi; |
641 | exp = TREE_OPERAND (TREE_OPERAND (exp, 0), 0); |
642 | } |
643 | } |
644 | } |
645 | goto done; |
646 | |
647 | default: |
648 | goto done; |
649 | } |
650 | |
651 | exp = TREE_OPERAND (exp, 0); |
652 | } |
653 | |
654 | done: |
655 | if (!bitsize.to_shwi (r: psize) || maybe_lt (a: *psize, b: 0)) |
656 | { |
657 | *poffset = 0; |
658 | *psize = -1; |
659 | *pmax_size = -1; |
660 | |
661 | return exp; |
662 | } |
663 | |
664 | /* ??? Due to negative offsets in ARRAY_REF we can end up with |
665 | negative bit_offset here. We might want to store a zero offset |
666 | in this case. */ |
667 | if (!bit_offset.to_shwi (r: poffset)) |
668 | { |
669 | *poffset = 0; |
670 | *pmax_size = -1; |
671 | |
672 | return exp; |
673 | } |
674 | |
675 | /* In case of a decl or constant base object we can do better. */ |
676 | |
677 | if (DECL_P (exp)) |
678 | { |
679 | if (VAR_P (exp) |
680 | && ((flag_unconstrained_commons && DECL_COMMON (exp)) |
681 | || (DECL_EXTERNAL (exp) && seen_variable_array_ref))) |
682 | { |
683 | tree sz_tree = TYPE_SIZE (TREE_TYPE (exp)); |
684 | /* If size is unknown, or we have read to the end, assume there |
685 | may be more to the structure than we are told. */ |
686 | if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE |
687 | || (seen_variable_array_ref |
688 | && (sz_tree == NULL_TREE |
689 | || !poly_int_tree_p (t: sz_tree) |
690 | || maybe_eq (a: bit_offset + maxsize, |
691 | b: wi::to_poly_offset (t: sz_tree))))) |
692 | maxsize = -1; |
693 | } |
694 | /* If maxsize is unknown adjust it according to the size of the |
695 | base decl. */ |
696 | else if (!known_size_p (a: maxsize) |
697 | && DECL_SIZE (exp) |
698 | && poly_int_tree_p (DECL_SIZE (exp))) |
699 | maxsize = wi::to_poly_offset (DECL_SIZE (exp)) - bit_offset; |
700 | } |
701 | else if (CONSTANT_CLASS_P (exp)) |
702 | { |
703 | /* If maxsize is unknown adjust it according to the size of the |
704 | base type constant. */ |
705 | if (!known_size_p (a: maxsize) |
706 | && TYPE_SIZE (TREE_TYPE (exp)) |
707 | && poly_int_tree_p (TYPE_SIZE (TREE_TYPE (exp)))) |
708 | maxsize = (wi::to_poly_offset (TYPE_SIZE (TREE_TYPE (exp))) |
709 | - bit_offset); |
710 | } |
711 | |
712 | if (!maxsize.to_shwi (r: pmax_size) |
713 | || maybe_lt (a: *pmax_size, b: 0) |
714 | || !endpoint_representable_p (pos: *poffset, size: *pmax_size)) |
715 | *pmax_size = -1; |
716 | |
717 | /* Punt if *POFFSET + *PSIZE overflows in HOST_WIDE_INT, the callers don't |
718 | check for such overflows individually and assume it works. */ |
719 | if (!endpoint_representable_p (pos: *poffset, size: *psize)) |
720 | { |
721 | *poffset = 0; |
722 | *psize = -1; |
723 | *pmax_size = -1; |
724 | |
725 | return exp; |
726 | } |
727 | |
728 | return exp; |
729 | } |
730 | |
731 | /* Like get_ref_base_and_extent, but for cases in which we only care |
732 | about constant-width accesses at constant offsets. Return null |
733 | if the access is anything else. */ |
734 | |
735 | tree |
736 | get_ref_base_and_extent_hwi (tree exp, HOST_WIDE_INT *poffset, |
737 | HOST_WIDE_INT *psize, bool *preverse) |
738 | { |
739 | poly_int64 offset, size, max_size; |
740 | HOST_WIDE_INT const_offset, const_size; |
741 | bool reverse; |
742 | tree decl = get_ref_base_and_extent (exp, poffset: &offset, psize: &size, pmax_size: &max_size, |
743 | preverse: &reverse); |
744 | if (!offset.is_constant (const_value: &const_offset) |
745 | || !size.is_constant (const_value: &const_size) |
746 | || const_offset < 0 |
747 | || !known_size_p (a: max_size) |
748 | || maybe_ne (a: max_size, b: const_size)) |
749 | return NULL_TREE; |
750 | |
751 | *poffset = const_offset; |
752 | *psize = const_size; |
753 | *preverse = reverse; |
754 | return decl; |
755 | } |
756 | |
757 | /* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that |
758 | denotes the starting address of the memory access EXP. |
759 | Returns NULL_TREE if the offset is not constant or any component |
760 | is not BITS_PER_UNIT-aligned. |
761 | VALUEIZE if non-NULL is used to valueize SSA names. It should return |
762 | its argument or a constant if the argument is known to be constant. */ |
763 | |
764 | tree |
765 | get_addr_base_and_unit_offset_1 (tree exp, poly_int64 *poffset, |
766 | tree (*valueize) (tree)) |
767 | { |
768 | poly_int64 byte_offset = 0; |
769 | |
770 | /* Compute cumulative byte-offset for nested component-refs and array-refs, |
771 | and find the ultimate containing object. */ |
772 | while (1) |
773 | { |
774 | switch (TREE_CODE (exp)) |
775 | { |
776 | case BIT_FIELD_REF: |
777 | { |
778 | poly_int64 this_byte_offset; |
779 | poly_uint64 this_bit_offset; |
780 | if (!poly_int_tree_p (TREE_OPERAND (exp, 2), value: &this_bit_offset) |
781 | || !multiple_p (a: this_bit_offset, BITS_PER_UNIT, |
782 | multiple: &this_byte_offset)) |
783 | return NULL_TREE; |
784 | byte_offset += this_byte_offset; |
785 | } |
786 | break; |
787 | |
788 | case COMPONENT_REF: |
789 | { |
790 | tree field = TREE_OPERAND (exp, 1); |
791 | tree this_offset = component_ref_field_offset (exp); |
792 | poly_int64 hthis_offset; |
793 | |
794 | if (!this_offset |
795 | || !poly_int_tree_p (t: this_offset, value: &hthis_offset) |
796 | || (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) |
797 | % BITS_PER_UNIT)) |
798 | return NULL_TREE; |
799 | |
800 | hthis_offset += (TREE_INT_CST_LOW (DECL_FIELD_BIT_OFFSET (field)) |
801 | / BITS_PER_UNIT); |
802 | byte_offset += hthis_offset; |
803 | } |
804 | break; |
805 | |
806 | case ARRAY_REF: |
807 | case ARRAY_RANGE_REF: |
808 | { |
809 | tree index = TREE_OPERAND (exp, 1); |
810 | tree low_bound, unit_size; |
811 | |
812 | if (valueize |
813 | && TREE_CODE (index) == SSA_NAME) |
814 | index = (*valueize) (index); |
815 | if (!poly_int_tree_p (t: index)) |
816 | return NULL_TREE; |
817 | low_bound = array_ref_low_bound (exp); |
818 | if (valueize |
819 | && TREE_CODE (low_bound) == SSA_NAME) |
820 | low_bound = (*valueize) (low_bound); |
821 | if (!poly_int_tree_p (t: low_bound)) |
822 | return NULL_TREE; |
823 | unit_size = array_ref_element_size (exp); |
824 | if (TREE_CODE (unit_size) != INTEGER_CST) |
825 | return NULL_TREE; |
826 | |
827 | /* If the resulting bit-offset is constant, track it. */ |
828 | poly_offset_int woffset |
829 | = wi::sext (a: wi::to_poly_offset (t: index) |
830 | - wi::to_poly_offset (t: low_bound), |
831 | TYPE_PRECISION (sizetype)); |
832 | woffset *= wi::to_offset (t: unit_size); |
833 | byte_offset += woffset.force_shwi (); |
834 | } |
835 | break; |
836 | |
837 | case REALPART_EXPR: |
838 | break; |
839 | |
840 | case IMAGPART_EXPR: |
841 | byte_offset += TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (exp))); |
842 | break; |
843 | |
844 | case VIEW_CONVERT_EXPR: |
845 | break; |
846 | |
847 | case MEM_REF: |
848 | { |
849 | tree base = TREE_OPERAND (exp, 0); |
850 | if (valueize |
851 | && TREE_CODE (base) == SSA_NAME) |
852 | base = (*valueize) (base); |
853 | |
854 | /* Hand back the decl for MEM[&decl, off]. */ |
855 | if (TREE_CODE (base) == ADDR_EXPR) |
856 | { |
857 | if (!integer_zerop (TREE_OPERAND (exp, 1))) |
858 | { |
859 | poly_offset_int off = mem_ref_offset (exp); |
860 | byte_offset += off.force_shwi (); |
861 | } |
862 | exp = TREE_OPERAND (base, 0); |
863 | } |
864 | goto done; |
865 | } |
866 | |
867 | case TARGET_MEM_REF: |
868 | { |
869 | tree base = TREE_OPERAND (exp, 0); |
870 | if (valueize |
871 | && TREE_CODE (base) == SSA_NAME) |
872 | base = (*valueize) (base); |
873 | |
874 | /* Hand back the decl for MEM[&decl, off]. */ |
875 | if (TREE_CODE (base) == ADDR_EXPR) |
876 | { |
877 | if (TMR_INDEX (exp) || TMR_INDEX2 (exp)) |
878 | return NULL_TREE; |
879 | if (!integer_zerop (TMR_OFFSET (exp))) |
880 | { |
881 | poly_offset_int off = mem_ref_offset (exp); |
882 | byte_offset += off.force_shwi (); |
883 | } |
884 | exp = TREE_OPERAND (base, 0); |
885 | } |
886 | goto done; |
887 | } |
888 | |
889 | default: |
890 | goto done; |
891 | } |
892 | |
893 | exp = TREE_OPERAND (exp, 0); |
894 | } |
895 | done: |
896 | |
897 | *poffset = byte_offset; |
898 | return exp; |
899 | } |
900 | |
901 | /* Returns the base object and a constant BITS_PER_UNIT offset in *POFFSET that |
902 | denotes the starting address of the memory access EXP. |
903 | Returns NULL_TREE if the offset is not constant or any component |
904 | is not BITS_PER_UNIT-aligned. */ |
905 | |
906 | tree |
907 | get_addr_base_and_unit_offset (tree exp, poly_int64 *poffset) |
908 | { |
909 | return get_addr_base_and_unit_offset_1 (exp, poffset, NULL); |
910 | } |
911 | |
912 | /* Returns true if STMT references an SSA_NAME that has |
913 | SSA_NAME_OCCURS_IN_ABNORMAL_PHI set, otherwise false. */ |
914 | |
915 | bool |
916 | stmt_references_abnormal_ssa_name (gimple *stmt) |
917 | { |
918 | ssa_op_iter oi; |
919 | use_operand_p use_p; |
920 | |
921 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE) |
922 | { |
923 | if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (USE_FROM_PTR (use_p))) |
924 | return true; |
925 | } |
926 | |
927 | return false; |
928 | } |
929 | |
930 | /* If STMT takes any abnormal PHI values as input, replace them with |
931 | local copies. */ |
932 | |
933 | void |
934 | replace_abnormal_ssa_names (gimple *stmt) |
935 | { |
936 | ssa_op_iter oi; |
937 | use_operand_p use_p; |
938 | |
939 | FOR_EACH_SSA_USE_OPERAND (use_p, stmt, oi, SSA_OP_USE) |
940 | { |
941 | tree op = USE_FROM_PTR (use_p); |
942 | if (TREE_CODE (op) == SSA_NAME && SSA_NAME_OCCURS_IN_ABNORMAL_PHI (op)) |
943 | { |
944 | gimple_stmt_iterator gsi = gsi_for_stmt (stmt); |
945 | tree new_name = make_ssa_name (TREE_TYPE (op)); |
946 | gassign *assign = gimple_build_assign (new_name, op); |
947 | gsi_insert_before (&gsi, assign, GSI_SAME_STMT); |
948 | SET_USE (use_p, new_name); |
949 | } |
950 | } |
951 | } |
952 | |
953 | /* Pair of tree and a sorting index, for dump_enumerated_decls. */ |
954 | struct GTY(()) numbered_tree |
955 | { |
956 | tree t; |
957 | int num; |
958 | }; |
959 | |
960 | |
961 | /* Compare two declarations references by their DECL_UID / sequence number. |
962 | Called via qsort. */ |
963 | |
964 | static int |
965 | compare_decls_by_uid (const void *pa, const void *pb) |
966 | { |
967 | const numbered_tree *nt_a = ((const numbered_tree *)pa); |
968 | const numbered_tree *nt_b = ((const numbered_tree *)pb); |
969 | |
970 | if (DECL_UID (nt_a->t) != DECL_UID (nt_b->t)) |
971 | return DECL_UID (nt_a->t) - DECL_UID (nt_b->t); |
972 | return nt_a->num - nt_b->num; |
973 | } |
974 | |
975 | /* Called via walk_gimple_stmt / walk_gimple_op by dump_enumerated_decls. */ |
976 | static tree |
977 | dump_enumerated_decls_push (tree *tp, int *walk_subtrees, void *data) |
978 | { |
979 | struct walk_stmt_info *wi = (struct walk_stmt_info *) data; |
980 | vec<numbered_tree> *list = (vec<numbered_tree> *) wi->info; |
981 | numbered_tree nt; |
982 | |
983 | if (!DECL_P (*tp)) |
984 | return NULL_TREE; |
985 | nt.t = *tp; |
986 | nt.num = list->length (); |
987 | list->safe_push (obj: nt); |
988 | *walk_subtrees = 0; |
989 | return NULL_TREE; |
990 | } |
991 | |
992 | /* Find all the declarations used by the current function, sort them by uid, |
993 | and emit the sorted list. Each declaration is tagged with a sequence |
994 | number indicating when it was found during statement / tree walking, |
995 | so that TDF_NOUID comparisons of anonymous declarations are still |
996 | meaningful. Where a declaration was encountered more than once, we |
997 | emit only the sequence number of the first encounter. |
998 | FILE is the dump file where to output the list and FLAGS is as in |
999 | print_generic_expr. */ |
1000 | void |
1001 | dump_enumerated_decls (FILE *file, dump_flags_t flags) |
1002 | { |
1003 | if (!cfun->cfg) |
1004 | return; |
1005 | |
1006 | basic_block bb; |
1007 | struct walk_stmt_info wi; |
1008 | auto_vec<numbered_tree, 40> decl_list; |
1009 | |
1010 | memset (s: &wi, c: '\0', n: sizeof (wi)); |
1011 | wi.info = (void *) &decl_list; |
1012 | FOR_EACH_BB_FN (bb, cfun) |
1013 | { |
1014 | gimple_stmt_iterator gsi; |
1015 | |
1016 | for (gsi = gsi_start_bb (bb); !gsi_end_p (i: gsi); gsi_next (i: &gsi)) |
1017 | if (!is_gimple_debug (gs: gsi_stmt (i: gsi))) |
1018 | walk_gimple_stmt (&gsi, NULL, dump_enumerated_decls_push, &wi); |
1019 | } |
1020 | decl_list.qsort (compare_decls_by_uid); |
1021 | if (decl_list.length ()) |
1022 | { |
1023 | unsigned ix; |
1024 | numbered_tree *ntp; |
1025 | tree last = NULL_TREE; |
1026 | |
1027 | fprintf (stream: file, format: "Declarations used by %s, sorted by DECL_UID:\n" , |
1028 | current_function_name ()); |
1029 | FOR_EACH_VEC_ELT (decl_list, ix, ntp) |
1030 | { |
1031 | if (ntp->t == last) |
1032 | continue; |
1033 | fprintf (stream: file, format: "%d: " , ntp->num); |
1034 | print_generic_decl (file, ntp->t, flags); |
1035 | fprintf (stream: file, format: "\n" ); |
1036 | last = ntp->t; |
1037 | } |
1038 | } |
1039 | } |
1040 | |