1 /* A pass for lowering trees to RTL.
2 Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
3 Free Software Foundation, Inc.
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 "tm.h"
25 #include "tree.h"
26 #include "rtl.h"
27 #include "tm_p.h"
28 #include "basic-block.h"
29 #include "function.h"
30 #include "expr.h"
31 #include "langhooks.h"
32 #include "tree-flow.h"
33 #include "timevar.h"
34 #include "tree-dump.h"
35 #include "tree-pass.h"
36 #include "except.h"
37 #include "flags.h"
38 #include "diagnostic.h"
39 #include "tree-pretty-print.h"
40 #include "gimple-pretty-print.h"
41 #include "toplev.h"
42 #include "debug.h"
43 #include "params.h"
44 #include "tree-inline.h"
45 #include "value-prof.h"
46 #include "target.h"
47 #include "ssaexpand.h"
48 #include "bitmap.h"
49 #include "sbitmap.h"
50 #include "insn-attr.h" /* For INSN_SCHEDULING. */
51
52 /* This variable holds information helping the rewriting of SSA trees
53 into RTL. */
54 struct ssaexpand SA;
55
56 /* This variable holds the currently expanded gimple statement for purposes
57 of comminucating the profile info to the builtin expanders. */
58 gimple currently_expanding_gimple_stmt;
59
60 static rtx expand_debug_expr (tree);
61
62 /* Return an expression tree corresponding to the RHS of GIMPLE
63 statement STMT. */
64
65 tree
gimple_assign_rhs_to_tree(gimple stmt)66 gimple_assign_rhs_to_tree (gimple stmt)
67 {
68 tree t;
69 enum gimple_rhs_class grhs_class;
70
71 grhs_class = get_gimple_rhs_class (gimple_expr_code (stmt));
72
73 if (grhs_class == GIMPLE_TERNARY_RHS)
74 t = build3 (gimple_assign_rhs_code (stmt),
75 TREE_TYPE (gimple_assign_lhs (stmt)),
76 gimple_assign_rhs1 (stmt),
77 gimple_assign_rhs2 (stmt),
78 gimple_assign_rhs3 (stmt));
79 else if (grhs_class == GIMPLE_BINARY_RHS)
80 t = build2 (gimple_assign_rhs_code (stmt),
81 TREE_TYPE (gimple_assign_lhs (stmt)),
82 gimple_assign_rhs1 (stmt),
83 gimple_assign_rhs2 (stmt));
84 else if (grhs_class == GIMPLE_UNARY_RHS)
85 t = build1 (gimple_assign_rhs_code (stmt),
86 TREE_TYPE (gimple_assign_lhs (stmt)),
87 gimple_assign_rhs1 (stmt));
88 else if (grhs_class == GIMPLE_SINGLE_RHS)
89 {
90 t = gimple_assign_rhs1 (stmt);
91 /* Avoid modifying this tree in place below. */
92 if ((gimple_has_location (stmt) && CAN_HAVE_LOCATION_P (t)
93 && gimple_location (stmt) != EXPR_LOCATION (t))
94 || (gimple_block (stmt)
95 && currently_expanding_to_rtl
96 && EXPR_P (t)
97 && gimple_block (stmt) != TREE_BLOCK (t)))
98 t = copy_node (t);
99 }
100 else
101 gcc_unreachable ();
102
103 if (gimple_has_location (stmt) && CAN_HAVE_LOCATION_P (t))
104 SET_EXPR_LOCATION (t, gimple_location (stmt));
105 if (gimple_block (stmt) && currently_expanding_to_rtl && EXPR_P (t))
106 TREE_BLOCK (t) = gimple_block (stmt);
107
108 return t;
109 }
110
111
112 #ifndef STACK_ALIGNMENT_NEEDED
113 #define STACK_ALIGNMENT_NEEDED 1
114 #endif
115
116 #define SSAVAR(x) (TREE_CODE (x) == SSA_NAME ? SSA_NAME_VAR (x) : x)
117
118 /* Associate declaration T with storage space X. If T is no
119 SSA name this is exactly SET_DECL_RTL, otherwise make the
120 partition of T associated with X. */
121 static inline void
set_rtl(tree t,rtx x)122 set_rtl (tree t, rtx x)
123 {
124 if (TREE_CODE (t) == SSA_NAME)
125 {
126 SA.partition_to_pseudo[var_to_partition (SA.map, t)] = x;
127 if (x && !MEM_P (x))
128 set_reg_attrs_for_decl_rtl (SSA_NAME_VAR (t), x);
129 /* For the benefit of debug information at -O0 (where vartracking
130 doesn't run) record the place also in the base DECL if it's
131 a normal variable (not a parameter). */
132 if (x && x != pc_rtx && TREE_CODE (SSA_NAME_VAR (t)) == VAR_DECL)
133 {
134 tree var = SSA_NAME_VAR (t);
135 /* If we don't yet have something recorded, just record it now. */
136 if (!DECL_RTL_SET_P (var))
137 SET_DECL_RTL (var, x);
138 /* If we have it set already to "multiple places" don't
139 change this. */
140 else if (DECL_RTL (var) == pc_rtx)
141 ;
142 /* If we have something recorded and it's not the same place
143 as we want to record now, we have multiple partitions for the
144 same base variable, with different places. We can't just
145 randomly chose one, hence we have to say that we don't know.
146 This only happens with optimization, and there var-tracking
147 will figure out the right thing. */
148 else if (DECL_RTL (var) != x)
149 SET_DECL_RTL (var, pc_rtx);
150 }
151 }
152 else
153 SET_DECL_RTL (t, x);
154 }
155
156 /* This structure holds data relevant to one variable that will be
157 placed in a stack slot. */
158 struct stack_var
159 {
160 /* The Variable. */
161 tree decl;
162
163 /* Initially, the size of the variable. Later, the size of the partition,
164 if this variable becomes it's partition's representative. */
165 HOST_WIDE_INT size;
166
167 /* The *byte* alignment required for this variable. Or as, with the
168 size, the alignment for this partition. */
169 unsigned int alignb;
170
171 /* The partition representative. */
172 size_t representative;
173
174 /* The next stack variable in the partition, or EOC. */
175 size_t next;
176
177 /* The numbers of conflicting stack variables. */
178 bitmap conflicts;
179 };
180
181 #define EOC ((size_t)-1)
182
183 /* We have an array of such objects while deciding allocation. */
184 static struct stack_var *stack_vars;
185 static size_t stack_vars_alloc;
186 static size_t stack_vars_num;
187 static struct pointer_map_t *decl_to_stack_part;
188
189 /* An array of indices such that stack_vars[stack_vars_sorted[i]].size
190 is non-decreasing. */
191 static size_t *stack_vars_sorted;
192
193 /* The phase of the stack frame. This is the known misalignment of
194 virtual_stack_vars_rtx from PREFERRED_STACK_BOUNDARY. That is,
195 (frame_offset+frame_phase) % PREFERRED_STACK_BOUNDARY == 0. */
196 static int frame_phase;
197
198 /* Used during expand_used_vars to remember if we saw any decls for
199 which we'd like to enable stack smashing protection. */
200 static bool has_protected_decls;
201
202 /* Used during expand_used_vars. Remember if we say a character buffer
203 smaller than our cutoff threshold. Used for -Wstack-protector. */
204 static bool has_short_buffer;
205
206 /* Compute the byte alignment to use for DECL. Ignore alignment
207 we can't do with expected alignment of the stack boundary. */
208
209 static unsigned int
align_local_variable(tree decl)210 align_local_variable (tree decl)
211 {
212 unsigned int align = LOCAL_DECL_ALIGNMENT (decl);
213 DECL_ALIGN (decl) = align;
214 return align / BITS_PER_UNIT;
215 }
216
217 /* Allocate SIZE bytes at byte alignment ALIGN from the stack frame.
218 Return the frame offset. */
219
220 static HOST_WIDE_INT
alloc_stack_frame_space(HOST_WIDE_INT size,unsigned HOST_WIDE_INT align)221 alloc_stack_frame_space (HOST_WIDE_INT size, unsigned HOST_WIDE_INT align)
222 {
223 HOST_WIDE_INT offset, new_frame_offset;
224
225 new_frame_offset = frame_offset;
226 if (FRAME_GROWS_DOWNWARD)
227 {
228 new_frame_offset -= size + frame_phase;
229 new_frame_offset &= -align;
230 new_frame_offset += frame_phase;
231 offset = new_frame_offset;
232 }
233 else
234 {
235 new_frame_offset -= frame_phase;
236 new_frame_offset += align - 1;
237 new_frame_offset &= -align;
238 new_frame_offset += frame_phase;
239 offset = new_frame_offset;
240 new_frame_offset += size;
241 }
242 frame_offset = new_frame_offset;
243
244 if (frame_offset_overflow (frame_offset, cfun->decl))
245 frame_offset = offset = 0;
246
247 return offset;
248 }
249
250 /* Accumulate DECL into STACK_VARS. */
251
252 static void
add_stack_var(tree decl)253 add_stack_var (tree decl)
254 {
255 struct stack_var *v;
256
257 if (stack_vars_num >= stack_vars_alloc)
258 {
259 if (stack_vars_alloc)
260 stack_vars_alloc = stack_vars_alloc * 3 / 2;
261 else
262 stack_vars_alloc = 32;
263 stack_vars
264 = XRESIZEVEC (struct stack_var, stack_vars, stack_vars_alloc);
265 }
266 if (!decl_to_stack_part)
267 decl_to_stack_part = pointer_map_create ();
268
269 v = &stack_vars[stack_vars_num];
270 * (size_t *)pointer_map_insert (decl_to_stack_part, decl) = stack_vars_num;
271
272 v->decl = decl;
273 v->size = tree_low_cst (DECL_SIZE_UNIT (SSAVAR (decl)), 1);
274 /* Ensure that all variables have size, so that &a != &b for any two
275 variables that are simultaneously live. */
276 if (v->size == 0)
277 v->size = 1;
278 v->alignb = align_local_variable (SSAVAR (decl));
279 /* An alignment of zero can mightily confuse us later. */
280 gcc_assert (v->alignb != 0);
281
282 /* All variables are initially in their own partition. */
283 v->representative = stack_vars_num;
284 v->next = EOC;
285
286 /* All variables initially conflict with no other. */
287 v->conflicts = NULL;
288
289 /* Ensure that this decl doesn't get put onto the list twice. */
290 set_rtl (decl, pc_rtx);
291
292 stack_vars_num++;
293 }
294
295 /* Make the decls associated with luid's X and Y conflict. */
296
297 static void
add_stack_var_conflict(size_t x,size_t y)298 add_stack_var_conflict (size_t x, size_t y)
299 {
300 struct stack_var *a = &stack_vars[x];
301 struct stack_var *b = &stack_vars[y];
302 if (!a->conflicts)
303 a->conflicts = BITMAP_ALLOC (NULL);
304 if (!b->conflicts)
305 b->conflicts = BITMAP_ALLOC (NULL);
306 bitmap_set_bit (a->conflicts, y);
307 bitmap_set_bit (b->conflicts, x);
308 }
309
310 /* Check whether the decls associated with luid's X and Y conflict. */
311
312 static bool
stack_var_conflict_p(size_t x,size_t y)313 stack_var_conflict_p (size_t x, size_t y)
314 {
315 struct stack_var *a = &stack_vars[x];
316 struct stack_var *b = &stack_vars[y];
317 if (x == y)
318 return false;
319 /* Partitions containing an SSA name result from gimple registers
320 with things like unsupported modes. They are top-level and
321 hence conflict with everything else. */
322 if (TREE_CODE (a->decl) == SSA_NAME || TREE_CODE (b->decl) == SSA_NAME)
323 return true;
324
325 if (!a->conflicts || !b->conflicts)
326 return false;
327 return bitmap_bit_p (a->conflicts, y);
328 }
329
330 /* Returns true if TYPE is or contains a union type. */
331
332 static bool
aggregate_contains_union_type(tree type)333 aggregate_contains_union_type (tree type)
334 {
335 tree field;
336
337 if (TREE_CODE (type) == UNION_TYPE
338 || TREE_CODE (type) == QUAL_UNION_TYPE)
339 return true;
340 if (TREE_CODE (type) == ARRAY_TYPE)
341 return aggregate_contains_union_type (TREE_TYPE (type));
342 if (TREE_CODE (type) != RECORD_TYPE)
343 return false;
344
345 for (field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
346 if (TREE_CODE (field) == FIELD_DECL)
347 if (aggregate_contains_union_type (TREE_TYPE (field)))
348 return true;
349
350 return false;
351 }
352
353 /* A subroutine of expand_used_vars. If two variables X and Y have alias
354 sets that do not conflict, then do add a conflict for these variables
355 in the interference graph. We also need to make sure to add conflicts
356 for union containing structures. Else RTL alias analysis comes along
357 and due to type based aliasing rules decides that for two overlapping
358 union temporaries { short s; int i; } accesses to the same mem through
359 different types may not alias and happily reorders stores across
360 life-time boundaries of the temporaries (See PR25654). */
361
362 static void
add_alias_set_conflicts(void)363 add_alias_set_conflicts (void)
364 {
365 size_t i, j, n = stack_vars_num;
366
367 for (i = 0; i < n; ++i)
368 {
369 tree type_i = TREE_TYPE (stack_vars[i].decl);
370 bool aggr_i = AGGREGATE_TYPE_P (type_i);
371 bool contains_union;
372
373 contains_union = aggregate_contains_union_type (type_i);
374 for (j = 0; j < i; ++j)
375 {
376 tree type_j = TREE_TYPE (stack_vars[j].decl);
377 bool aggr_j = AGGREGATE_TYPE_P (type_j);
378 if (aggr_i != aggr_j
379 /* Either the objects conflict by means of type based
380 aliasing rules, or we need to add a conflict. */
381 || !objects_must_conflict_p (type_i, type_j)
382 /* In case the types do not conflict ensure that access
383 to elements will conflict. In case of unions we have
384 to be careful as type based aliasing rules may say
385 access to the same memory does not conflict. So play
386 safe and add a conflict in this case when
387 -fstrict-aliasing is used. */
388 || (contains_union && flag_strict_aliasing))
389 add_stack_var_conflict (i, j);
390 }
391 }
392 }
393
394 /* Callback for walk_stmt_ops. If OP is a decl touched by add_stack_var
395 enter its partition number into bitmap DATA. */
396
397 static bool
visit_op(gimple stmt ATTRIBUTE_UNUSED,tree op,void * data)398 visit_op (gimple stmt ATTRIBUTE_UNUSED, tree op, void *data)
399 {
400 bitmap active = (bitmap)data;
401 op = get_base_address (op);
402 if (op
403 && DECL_P (op)
404 && DECL_RTL_IF_SET (op) == pc_rtx)
405 {
406 size_t *v = (size_t *) pointer_map_contains (decl_to_stack_part, op);
407 if (v)
408 bitmap_set_bit (active, *v);
409 }
410 return false;
411 }
412
413 /* Callback for walk_stmt_ops. If OP is a decl touched by add_stack_var
414 record conflicts between it and all currently active other partitions
415 from bitmap DATA. */
416
417 static bool
visit_conflict(gimple stmt ATTRIBUTE_UNUSED,tree op,void * data)418 visit_conflict (gimple stmt ATTRIBUTE_UNUSED, tree op, void *data)
419 {
420 bitmap active = (bitmap)data;
421 op = get_base_address (op);
422 if (op
423 && DECL_P (op)
424 && DECL_RTL_IF_SET (op) == pc_rtx)
425 {
426 size_t *v =
427 (size_t *) pointer_map_contains (decl_to_stack_part, op);
428 if (v && bitmap_set_bit (active, *v))
429 {
430 size_t num = *v;
431 bitmap_iterator bi;
432 unsigned i;
433 gcc_assert (num < stack_vars_num);
434 EXECUTE_IF_SET_IN_BITMAP (active, 0, i, bi)
435 add_stack_var_conflict (num, i);
436 }
437 }
438 return false;
439 }
440
441 /* Helper routine for add_scope_conflicts, calculating the active partitions
442 at the end of BB, leaving the result in WORK. We're called to generate
443 conflicts when FOR_CONFLICT is true, otherwise we're just tracking
444 liveness. */
445
446 static void
add_scope_conflicts_1(basic_block bb,bitmap work,bool for_conflict)447 add_scope_conflicts_1 (basic_block bb, bitmap work, bool for_conflict)
448 {
449 edge e;
450 edge_iterator ei;
451 gimple_stmt_iterator gsi;
452 bool (*visit)(gimple, tree, void *);
453
454 bitmap_clear (work);
455 FOR_EACH_EDGE (e, ei, bb->preds)
456 bitmap_ior_into (work, (bitmap)e->src->aux);
457
458 visit = visit_op;
459
460 for (gsi = gsi_start_phis (bb); !gsi_end_p (gsi); gsi_next (&gsi))
461 {
462 gimple stmt = gsi_stmt (gsi);
463 walk_stmt_load_store_addr_ops (stmt, work, NULL, NULL, visit);
464 }
465 for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi); gsi_next (&gsi))
466 {
467 gimple stmt = gsi_stmt (gsi);
468
469 if (gimple_clobber_p (stmt))
470 {
471 tree lhs = gimple_assign_lhs (stmt);
472 size_t *v;
473 /* Nested function lowering might introduce LHSs
474 that are COMPONENT_REFs. */
475 if (TREE_CODE (lhs) != VAR_DECL)
476 continue;
477 if (DECL_RTL_IF_SET (lhs) == pc_rtx
478 && (v = (size_t *)
479 pointer_map_contains (decl_to_stack_part, lhs)))
480 bitmap_clear_bit (work, *v);
481 }
482 else if (!is_gimple_debug (stmt))
483 {
484 if (for_conflict
485 && visit == visit_op)
486 {
487 /* If this is the first real instruction in this BB we need
488 to add conflicts for everything live at this point now.
489 Unlike classical liveness for named objects we can't
490 rely on seeing a def/use of the names we're interested in.
491 There might merely be indirect loads/stores. We'd not add any
492 conflicts for such partitions. */
493 bitmap_iterator bi;
494 unsigned i;
495 EXECUTE_IF_SET_IN_BITMAP (work, 0, i, bi)
496 {
497 unsigned j;
498 bitmap_iterator bj;
499 EXECUTE_IF_SET_IN_BITMAP (work, i + 1, j, bj)
500 add_stack_var_conflict (i, j);
501 }
502 visit = visit_conflict;
503 }
504 walk_stmt_load_store_addr_ops (stmt, work, visit, visit, visit);
505 }
506 }
507 }
508
509 /* Generate stack partition conflicts between all partitions that are
510 simultaneously live. */
511
512 static void
add_scope_conflicts(void)513 add_scope_conflicts (void)
514 {
515 basic_block bb;
516 bool changed;
517 bitmap work = BITMAP_ALLOC (NULL);
518
519 /* We approximate the live range of a stack variable by taking the first
520 mention of its name as starting point(s), and by the end-of-scope
521 death clobber added by gimplify as ending point(s) of the range.
522 This overapproximates in the case we for instance moved an address-taken
523 operation upward, without also moving a dereference to it upwards.
524 But it's conservatively correct as a variable never can hold values
525 before its name is mentioned at least once.
526
527 We then do a mostly classical bitmap liveness algorithm. */
528
529 FOR_ALL_BB (bb)
530 bb->aux = BITMAP_ALLOC (NULL);
531
532 changed = true;
533 while (changed)
534 {
535 changed = false;
536 FOR_EACH_BB (bb)
537 {
538 bitmap active = (bitmap)bb->aux;
539 add_scope_conflicts_1 (bb, work, false);
540 if (bitmap_ior_into (active, work))
541 changed = true;
542 }
543 }
544
545 FOR_EACH_BB (bb)
546 add_scope_conflicts_1 (bb, work, true);
547
548 BITMAP_FREE (work);
549 FOR_ALL_BB (bb)
550 BITMAP_FREE (bb->aux);
551 }
552
553 /* A subroutine of partition_stack_vars. A comparison function for qsort,
554 sorting an array of indices by the properties of the object. */
555
556 static int
stack_var_cmp(const void * a,const void * b)557 stack_var_cmp (const void *a, const void *b)
558 {
559 size_t ia = *(const size_t *)a;
560 size_t ib = *(const size_t *)b;
561 unsigned int aligna = stack_vars[ia].alignb;
562 unsigned int alignb = stack_vars[ib].alignb;
563 HOST_WIDE_INT sizea = stack_vars[ia].size;
564 HOST_WIDE_INT sizeb = stack_vars[ib].size;
565 tree decla = stack_vars[ia].decl;
566 tree declb = stack_vars[ib].decl;
567 bool largea, largeb;
568 unsigned int uida, uidb;
569
570 /* Primary compare on "large" alignment. Large comes first. */
571 largea = (aligna * BITS_PER_UNIT > MAX_SUPPORTED_STACK_ALIGNMENT);
572 largeb = (alignb * BITS_PER_UNIT > MAX_SUPPORTED_STACK_ALIGNMENT);
573 if (largea != largeb)
574 return (int)largeb - (int)largea;
575
576 /* Secondary compare on size, decreasing */
577 if (sizea > sizeb)
578 return -1;
579 if (sizea < sizeb)
580 return 1;
581
582 /* Tertiary compare on true alignment, decreasing. */
583 if (aligna < alignb)
584 return -1;
585 if (aligna > alignb)
586 return 1;
587
588 /* Final compare on ID for sort stability, increasing.
589 Two SSA names are compared by their version, SSA names come before
590 non-SSA names, and two normal decls are compared by their DECL_UID. */
591 if (TREE_CODE (decla) == SSA_NAME)
592 {
593 if (TREE_CODE (declb) == SSA_NAME)
594 uida = SSA_NAME_VERSION (decla), uidb = SSA_NAME_VERSION (declb);
595 else
596 return -1;
597 }
598 else if (TREE_CODE (declb) == SSA_NAME)
599 return 1;
600 else
601 uida = DECL_UID (decla), uidb = DECL_UID (declb);
602 if (uida < uidb)
603 return 1;
604 if (uida > uidb)
605 return -1;
606 return 0;
607 }
608
609
610 /* If the points-to solution *PI points to variables that are in a partition
611 together with other variables add all partition members to the pointed-to
612 variables bitmap. */
613
614 static void
add_partitioned_vars_to_ptset(struct pt_solution * pt,struct pointer_map_t * decls_to_partitions,struct pointer_set_t * visited,bitmap temp)615 add_partitioned_vars_to_ptset (struct pt_solution *pt,
616 struct pointer_map_t *decls_to_partitions,
617 struct pointer_set_t *visited, bitmap temp)
618 {
619 bitmap_iterator bi;
620 unsigned i;
621 bitmap *part;
622
623 if (pt->anything
624 || pt->vars == NULL
625 /* The pointed-to vars bitmap is shared, it is enough to
626 visit it once. */
627 || pointer_set_insert(visited, pt->vars))
628 return;
629
630 bitmap_clear (temp);
631
632 /* By using a temporary bitmap to store all members of the partitions
633 we have to add we make sure to visit each of the partitions only
634 once. */
635 EXECUTE_IF_SET_IN_BITMAP (pt->vars, 0, i, bi)
636 if ((!temp
637 || !bitmap_bit_p (temp, i))
638 && (part = (bitmap *) pointer_map_contains (decls_to_partitions,
639 (void *)(size_t) i)))
640 bitmap_ior_into (temp, *part);
641 if (!bitmap_empty_p (temp))
642 bitmap_ior_into (pt->vars, temp);
643 }
644
645 /* Update points-to sets based on partition info, so we can use them on RTL.
646 The bitmaps representing stack partitions will be saved until expand,
647 where partitioned decls used as bases in memory expressions will be
648 rewritten. */
649
650 static void
update_alias_info_with_stack_vars(void)651 update_alias_info_with_stack_vars (void)
652 {
653 struct pointer_map_t *decls_to_partitions = NULL;
654 size_t i, j;
655 tree var = NULL_TREE;
656
657 for (i = 0; i < stack_vars_num; i++)
658 {
659 bitmap part = NULL;
660 tree name;
661 struct ptr_info_def *pi;
662
663 /* Not interested in partitions with single variable. */
664 if (stack_vars[i].representative != i
665 || stack_vars[i].next == EOC)
666 continue;
667
668 if (!decls_to_partitions)
669 {
670 decls_to_partitions = pointer_map_create ();
671 cfun->gimple_df->decls_to_pointers = pointer_map_create ();
672 }
673
674 /* Create an SSA_NAME that points to the partition for use
675 as base during alias-oracle queries on RTL for bases that
676 have been partitioned. */
677 if (var == NULL_TREE)
678 var = create_tmp_var (ptr_type_node, NULL);
679 name = make_ssa_name (var, NULL);
680
681 /* Create bitmaps representing partitions. They will be used for
682 points-to sets later, so use GGC alloc. */
683 part = BITMAP_GGC_ALLOC ();
684 for (j = i; j != EOC; j = stack_vars[j].next)
685 {
686 tree decl = stack_vars[j].decl;
687 unsigned int uid = DECL_PT_UID (decl);
688 /* We should never end up partitioning SSA names (though they
689 may end up on the stack). Neither should we allocate stack
690 space to something that is unused and thus unreferenced, except
691 for -O0 where we are preserving even unreferenced variables. */
692 gcc_assert (DECL_P (decl)
693 && (!optimize
694 || referenced_var_lookup (cfun, DECL_UID (decl))));
695 bitmap_set_bit (part, uid);
696 *((bitmap *) pointer_map_insert (decls_to_partitions,
697 (void *)(size_t) uid)) = part;
698 *((tree *) pointer_map_insert (cfun->gimple_df->decls_to_pointers,
699 decl)) = name;
700 if (TREE_ADDRESSABLE (decl))
701 TREE_ADDRESSABLE (name) = 1;
702 }
703
704 /* Make the SSA name point to all partition members. */
705 pi = get_ptr_info (name);
706 pt_solution_set (&pi->pt, part, false);
707 }
708
709 /* Make all points-to sets that contain one member of a partition
710 contain all members of the partition. */
711 if (decls_to_partitions)
712 {
713 unsigned i;
714 struct pointer_set_t *visited = pointer_set_create ();
715 bitmap temp = BITMAP_ALLOC (NULL);
716
717 for (i = 1; i < num_ssa_names; i++)
718 {
719 tree name = ssa_name (i);
720 struct ptr_info_def *pi;
721
722 if (name
723 && POINTER_TYPE_P (TREE_TYPE (name))
724 && ((pi = SSA_NAME_PTR_INFO (name)) != NULL))
725 add_partitioned_vars_to_ptset (&pi->pt, decls_to_partitions,
726 visited, temp);
727 }
728
729 add_partitioned_vars_to_ptset (&cfun->gimple_df->escaped,
730 decls_to_partitions, visited, temp);
731
732 pointer_set_destroy (visited);
733 pointer_map_destroy (decls_to_partitions);
734 BITMAP_FREE (temp);
735 }
736 }
737
738 /* A subroutine of partition_stack_vars. The UNION portion of a UNION/FIND
739 partitioning algorithm. Partitions A and B are known to be non-conflicting.
740 Merge them into a single partition A. */
741
742 static void
union_stack_vars(size_t a,size_t b)743 union_stack_vars (size_t a, size_t b)
744 {
745 struct stack_var *vb = &stack_vars[b];
746 bitmap_iterator bi;
747 unsigned u;
748
749 gcc_assert (stack_vars[b].next == EOC);
750 /* Add B to A's partition. */
751 stack_vars[b].next = stack_vars[a].next;
752 stack_vars[b].representative = a;
753 stack_vars[a].next = b;
754
755 /* Update the required alignment of partition A to account for B. */
756 if (stack_vars[a].alignb < stack_vars[b].alignb)
757 stack_vars[a].alignb = stack_vars[b].alignb;
758
759 /* Update the interference graph and merge the conflicts. */
760 if (vb->conflicts)
761 {
762 EXECUTE_IF_SET_IN_BITMAP (vb->conflicts, 0, u, bi)
763 add_stack_var_conflict (a, stack_vars[u].representative);
764 BITMAP_FREE (vb->conflicts);
765 }
766 }
767
768 /* A subroutine of expand_used_vars. Binpack the variables into
769 partitions constrained by the interference graph. The overall
770 algorithm used is as follows:
771
772 Sort the objects by size in descending order.
773 For each object A {
774 S = size(A)
775 O = 0
776 loop {
777 Look for the largest non-conflicting object B with size <= S.
778 UNION (A, B)
779 }
780 }
781 */
782
783 static void
partition_stack_vars(void)784 partition_stack_vars (void)
785 {
786 size_t si, sj, n = stack_vars_num;
787
788 stack_vars_sorted = XNEWVEC (size_t, stack_vars_num);
789 for (si = 0; si < n; ++si)
790 stack_vars_sorted[si] = si;
791
792 if (n == 1)
793 return;
794
795 qsort (stack_vars_sorted, n, sizeof (size_t), stack_var_cmp);
796
797 for (si = 0; si < n; ++si)
798 {
799 size_t i = stack_vars_sorted[si];
800 unsigned int ialign = stack_vars[i].alignb;
801
802 /* Ignore objects that aren't partition representatives. If we
803 see a var that is not a partition representative, it must
804 have been merged earlier. */
805 if (stack_vars[i].representative != i)
806 continue;
807
808 for (sj = si + 1; sj < n; ++sj)
809 {
810 size_t j = stack_vars_sorted[sj];
811 unsigned int jalign = stack_vars[j].alignb;
812
813 /* Ignore objects that aren't partition representatives. */
814 if (stack_vars[j].representative != j)
815 continue;
816
817 /* Ignore conflicting objects. */
818 if (stack_var_conflict_p (i, j))
819 continue;
820
821 /* Do not mix objects of "small" (supported) alignment
822 and "large" (unsupported) alignment. */
823 if ((ialign * BITS_PER_UNIT <= MAX_SUPPORTED_STACK_ALIGNMENT)
824 != (jalign * BITS_PER_UNIT <= MAX_SUPPORTED_STACK_ALIGNMENT))
825 continue;
826
827 /* UNION the objects, placing J at OFFSET. */
828 union_stack_vars (i, j);
829 }
830 }
831
832 update_alias_info_with_stack_vars ();
833 }
834
835 /* A debugging aid for expand_used_vars. Dump the generated partitions. */
836
837 static void
dump_stack_var_partition(void)838 dump_stack_var_partition (void)
839 {
840 size_t si, i, j, n = stack_vars_num;
841
842 for (si = 0; si < n; ++si)
843 {
844 i = stack_vars_sorted[si];
845
846 /* Skip variables that aren't partition representatives, for now. */
847 if (stack_vars[i].representative != i)
848 continue;
849
850 fprintf (dump_file, "Partition %lu: size " HOST_WIDE_INT_PRINT_DEC
851 " align %u\n", (unsigned long) i, stack_vars[i].size,
852 stack_vars[i].alignb);
853
854 for (j = i; j != EOC; j = stack_vars[j].next)
855 {
856 fputc ('\t', dump_file);
857 print_generic_expr (dump_file, stack_vars[j].decl, dump_flags);
858 }
859 fputc ('\n', dump_file);
860 }
861 }
862
863 /* Assign rtl to DECL at BASE + OFFSET. */
864
865 static void
expand_one_stack_var_at(tree decl,rtx base,unsigned base_align,HOST_WIDE_INT offset)866 expand_one_stack_var_at (tree decl, rtx base, unsigned base_align,
867 HOST_WIDE_INT offset)
868 {
869 unsigned align;
870 rtx x;
871
872 /* If this fails, we've overflowed the stack frame. Error nicely? */
873 gcc_assert (offset == trunc_int_for_mode (offset, Pmode));
874
875 x = plus_constant (base, offset);
876 x = gen_rtx_MEM (DECL_MODE (SSAVAR (decl)), x);
877
878 if (TREE_CODE (decl) != SSA_NAME)
879 {
880 /* Set alignment we actually gave this decl if it isn't an SSA name.
881 If it is we generate stack slots only accidentally so it isn't as
882 important, we'll simply use the alignment that is already set. */
883 if (base == virtual_stack_vars_rtx)
884 offset -= frame_phase;
885 align = offset & -offset;
886 align *= BITS_PER_UNIT;
887 if (align == 0 || align > base_align)
888 align = base_align;
889
890 /* One would think that we could assert that we're not decreasing
891 alignment here, but (at least) the i386 port does exactly this
892 via the MINIMUM_ALIGNMENT hook. */
893
894 DECL_ALIGN (decl) = align;
895 DECL_USER_ALIGN (decl) = 0;
896 }
897
898 set_mem_attributes (x, SSAVAR (decl), true);
899 set_rtl (decl, x);
900 }
901
902 /* A subroutine of expand_used_vars. Give each partition representative
903 a unique location within the stack frame. Update each partition member
904 with that location. */
905
906 static void
expand_stack_vars(bool (* pred)(tree))907 expand_stack_vars (bool (*pred) (tree))
908 {
909 size_t si, i, j, n = stack_vars_num;
910 HOST_WIDE_INT large_size = 0, large_alloc = 0;
911 rtx large_base = NULL;
912 unsigned large_align = 0;
913 tree decl;
914
915 /* Determine if there are any variables requiring "large" alignment.
916 Since these are dynamically allocated, we only process these if
917 no predicate involved. */
918 large_align = stack_vars[stack_vars_sorted[0]].alignb * BITS_PER_UNIT;
919 if (pred == NULL && large_align > MAX_SUPPORTED_STACK_ALIGNMENT)
920 {
921 /* Find the total size of these variables. */
922 for (si = 0; si < n; ++si)
923 {
924 unsigned alignb;
925
926 i = stack_vars_sorted[si];
927 alignb = stack_vars[i].alignb;
928
929 /* Stop when we get to the first decl with "small" alignment. */
930 if (alignb * BITS_PER_UNIT <= MAX_SUPPORTED_STACK_ALIGNMENT)
931 break;
932
933 /* Skip variables that aren't partition representatives. */
934 if (stack_vars[i].representative != i)
935 continue;
936
937 /* Skip variables that have already had rtl assigned. See also
938 add_stack_var where we perpetrate this pc_rtx hack. */
939 decl = stack_vars[i].decl;
940 if ((TREE_CODE (decl) == SSA_NAME
941 ? SA.partition_to_pseudo[var_to_partition (SA.map, decl)]
942 : DECL_RTL (decl)) != pc_rtx)
943 continue;
944
945 large_size += alignb - 1;
946 large_size &= -(HOST_WIDE_INT)alignb;
947 large_size += stack_vars[i].size;
948 }
949
950 /* If there were any, allocate space. */
951 if (large_size > 0)
952 large_base = allocate_dynamic_stack_space (GEN_INT (large_size), 0,
953 large_align, true);
954 }
955
956 for (si = 0; si < n; ++si)
957 {
958 rtx base;
959 unsigned base_align, alignb;
960 HOST_WIDE_INT offset;
961
962 i = stack_vars_sorted[si];
963
964 /* Skip variables that aren't partition representatives, for now. */
965 if (stack_vars[i].representative != i)
966 continue;
967
968 /* Skip variables that have already had rtl assigned. See also
969 add_stack_var where we perpetrate this pc_rtx hack. */
970 decl = stack_vars[i].decl;
971 if ((TREE_CODE (decl) == SSA_NAME
972 ? SA.partition_to_pseudo[var_to_partition (SA.map, decl)]
973 : DECL_RTL (decl)) != pc_rtx)
974 continue;
975
976 /* Check the predicate to see whether this variable should be
977 allocated in this pass. */
978 if (pred && !pred (decl))
979 continue;
980
981 alignb = stack_vars[i].alignb;
982 if (alignb * BITS_PER_UNIT <= MAX_SUPPORTED_STACK_ALIGNMENT)
983 {
984 offset = alloc_stack_frame_space (stack_vars[i].size, alignb);
985 base = virtual_stack_vars_rtx;
986 base_align = crtl->max_used_stack_slot_alignment;
987 }
988 else
989 {
990 /* Large alignment is only processed in the last pass. */
991 if (pred)
992 continue;
993 gcc_assert (large_base != NULL);
994
995 large_alloc += alignb - 1;
996 large_alloc &= -(HOST_WIDE_INT)alignb;
997 offset = large_alloc;
998 large_alloc += stack_vars[i].size;
999
1000 base = large_base;
1001 base_align = large_align;
1002 }
1003
1004 /* Create rtl for each variable based on their location within the
1005 partition. */
1006 for (j = i; j != EOC; j = stack_vars[j].next)
1007 {
1008 expand_one_stack_var_at (stack_vars[j].decl,
1009 base, base_align,
1010 offset);
1011 }
1012 }
1013
1014 gcc_assert (large_alloc == large_size);
1015 }
1016
1017 /* Take into account all sizes of partitions and reset DECL_RTLs. */
1018 static HOST_WIDE_INT
account_stack_vars(void)1019 account_stack_vars (void)
1020 {
1021 size_t si, j, i, n = stack_vars_num;
1022 HOST_WIDE_INT size = 0;
1023
1024 for (si = 0; si < n; ++si)
1025 {
1026 i = stack_vars_sorted[si];
1027
1028 /* Skip variables that aren't partition representatives, for now. */
1029 if (stack_vars[i].representative != i)
1030 continue;
1031
1032 size += stack_vars[i].size;
1033 for (j = i; j != EOC; j = stack_vars[j].next)
1034 set_rtl (stack_vars[j].decl, NULL);
1035 }
1036 return size;
1037 }
1038
1039 /* A subroutine of expand_one_var. Called to immediately assign rtl
1040 to a variable to be allocated in the stack frame. */
1041
1042 static void
expand_one_stack_var(tree var)1043 expand_one_stack_var (tree var)
1044 {
1045 HOST_WIDE_INT size, offset;
1046 unsigned byte_align;
1047
1048 size = tree_low_cst (DECL_SIZE_UNIT (SSAVAR (var)), 1);
1049 byte_align = align_local_variable (SSAVAR (var));
1050
1051 /* We handle highly aligned variables in expand_stack_vars. */
1052 gcc_assert (byte_align * BITS_PER_UNIT <= MAX_SUPPORTED_STACK_ALIGNMENT);
1053
1054 offset = alloc_stack_frame_space (size, byte_align);
1055
1056 expand_one_stack_var_at (var, virtual_stack_vars_rtx,
1057 crtl->max_used_stack_slot_alignment, offset);
1058 }
1059
1060 /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL
1061 that will reside in a hard register. */
1062
1063 static void
expand_one_hard_reg_var(tree var)1064 expand_one_hard_reg_var (tree var)
1065 {
1066 rest_of_decl_compilation (var, 0, 0);
1067 }
1068
1069 /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL
1070 that will reside in a pseudo register. */
1071
1072 static void
expand_one_register_var(tree var)1073 expand_one_register_var (tree var)
1074 {
1075 tree decl = SSAVAR (var);
1076 tree type = TREE_TYPE (decl);
1077 enum machine_mode reg_mode = promote_decl_mode (decl, NULL);
1078 rtx x = gen_reg_rtx (reg_mode);
1079
1080 set_rtl (var, x);
1081
1082 /* Note if the object is a user variable. */
1083 if (!DECL_ARTIFICIAL (decl))
1084 mark_user_reg (x);
1085
1086 if (POINTER_TYPE_P (type))
1087 mark_reg_pointer (x, get_pointer_alignment (var));
1088 }
1089
1090 /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL that
1091 has some associated error, e.g. its type is error-mark. We just need
1092 to pick something that won't crash the rest of the compiler. */
1093
1094 static void
expand_one_error_var(tree var)1095 expand_one_error_var (tree var)
1096 {
1097 enum machine_mode mode = DECL_MODE (var);
1098 rtx x;
1099
1100 if (mode == BLKmode)
1101 x = gen_rtx_MEM (BLKmode, const0_rtx);
1102 else if (mode == VOIDmode)
1103 x = const0_rtx;
1104 else
1105 x = gen_reg_rtx (mode);
1106
1107 SET_DECL_RTL (var, x);
1108 }
1109
1110 /* A subroutine of expand_one_var. VAR is a variable that will be
1111 allocated to the local stack frame. Return true if we wish to
1112 add VAR to STACK_VARS so that it will be coalesced with other
1113 variables. Return false to allocate VAR immediately.
1114
1115 This function is used to reduce the number of variables considered
1116 for coalescing, which reduces the size of the quadratic problem. */
1117
1118 static bool
defer_stack_allocation(tree var,bool toplevel)1119 defer_stack_allocation (tree var, bool toplevel)
1120 {
1121 /* If stack protection is enabled, *all* stack variables must be deferred,
1122 so that we can re-order the strings to the top of the frame. */
1123 if (flag_stack_protect)
1124 return true;
1125
1126 /* We handle "large" alignment via dynamic allocation. We want to handle
1127 this extra complication in only one place, so defer them. */
1128 if (DECL_ALIGN (var) > MAX_SUPPORTED_STACK_ALIGNMENT)
1129 return true;
1130
1131 /* Variables in the outermost scope automatically conflict with
1132 every other variable. The only reason to want to defer them
1133 at all is that, after sorting, we can more efficiently pack
1134 small variables in the stack frame. Continue to defer at -O2. */
1135 if (toplevel && optimize < 2)
1136 return false;
1137
1138 /* Without optimization, *most* variables are allocated from the
1139 stack, which makes the quadratic problem large exactly when we
1140 want compilation to proceed as quickly as possible. On the
1141 other hand, we don't want the function's stack frame size to
1142 get completely out of hand. So we avoid adding scalars and
1143 "small" aggregates to the list at all. */
1144 if (optimize == 0 && tree_low_cst (DECL_SIZE_UNIT (var), 1) < 32)
1145 return false;
1146
1147 return true;
1148 }
1149
1150 /* A subroutine of expand_used_vars. Expand one variable according to
1151 its flavor. Variables to be placed on the stack are not actually
1152 expanded yet, merely recorded.
1153 When REALLY_EXPAND is false, only add stack values to be allocated.
1154 Return stack usage this variable is supposed to take.
1155 */
1156
1157 static HOST_WIDE_INT
expand_one_var(tree var,bool toplevel,bool really_expand)1158 expand_one_var (tree var, bool toplevel, bool really_expand)
1159 {
1160 unsigned int align = BITS_PER_UNIT;
1161 tree origvar = var;
1162
1163 var = SSAVAR (var);
1164
1165 if (TREE_TYPE (var) != error_mark_node && TREE_CODE (var) == VAR_DECL)
1166 {
1167 /* Because we don't know if VAR will be in register or on stack,
1168 we conservatively assume it will be on stack even if VAR is
1169 eventually put into register after RA pass. For non-automatic
1170 variables, which won't be on stack, we collect alignment of
1171 type and ignore user specified alignment. */
1172 if (TREE_STATIC (var) || DECL_EXTERNAL (var))
1173 align = MINIMUM_ALIGNMENT (TREE_TYPE (var),
1174 TYPE_MODE (TREE_TYPE (var)),
1175 TYPE_ALIGN (TREE_TYPE (var)));
1176 else if (DECL_HAS_VALUE_EXPR_P (var)
1177 || (DECL_RTL_SET_P (var) && MEM_P (DECL_RTL (var))))
1178 /* Don't consider debug only variables with DECL_HAS_VALUE_EXPR_P set
1179 or variables which were assigned a stack slot already by
1180 expand_one_stack_var_at - in the latter case DECL_ALIGN has been
1181 changed from the offset chosen to it. */
1182 align = crtl->stack_alignment_estimated;
1183 else
1184 align = MINIMUM_ALIGNMENT (var, DECL_MODE (var), DECL_ALIGN (var));
1185
1186 /* If the variable alignment is very large we'll dynamicaly allocate
1187 it, which means that in-frame portion is just a pointer. */
1188 if (align > MAX_SUPPORTED_STACK_ALIGNMENT)
1189 align = POINTER_SIZE;
1190 }
1191
1192 if (SUPPORTS_STACK_ALIGNMENT
1193 && crtl->stack_alignment_estimated < align)
1194 {
1195 /* stack_alignment_estimated shouldn't change after stack
1196 realign decision made */
1197 gcc_assert(!crtl->stack_realign_processed);
1198 crtl->stack_alignment_estimated = align;
1199 }
1200
1201 /* stack_alignment_needed > PREFERRED_STACK_BOUNDARY is permitted.
1202 So here we only make sure stack_alignment_needed >= align. */
1203 if (crtl->stack_alignment_needed < align)
1204 crtl->stack_alignment_needed = align;
1205 if (crtl->max_used_stack_slot_alignment < align)
1206 crtl->max_used_stack_slot_alignment = align;
1207
1208 if (TREE_CODE (origvar) == SSA_NAME)
1209 {
1210 gcc_assert (TREE_CODE (var) != VAR_DECL
1211 || (!DECL_EXTERNAL (var)
1212 && !DECL_HAS_VALUE_EXPR_P (var)
1213 && !TREE_STATIC (var)
1214 && TREE_TYPE (var) != error_mark_node
1215 && !DECL_HARD_REGISTER (var)
1216 && really_expand));
1217 }
1218 if (TREE_CODE (var) != VAR_DECL && TREE_CODE (origvar) != SSA_NAME)
1219 ;
1220 else if (DECL_EXTERNAL (var))
1221 ;
1222 else if (DECL_HAS_VALUE_EXPR_P (var))
1223 ;
1224 else if (TREE_STATIC (var))
1225 ;
1226 else if (TREE_CODE (origvar) != SSA_NAME && DECL_RTL_SET_P (var))
1227 ;
1228 else if (TREE_TYPE (var) == error_mark_node)
1229 {
1230 if (really_expand)
1231 expand_one_error_var (var);
1232 }
1233 else if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var))
1234 {
1235 if (really_expand)
1236 expand_one_hard_reg_var (var);
1237 }
1238 else if (use_register_for_decl (var))
1239 {
1240 if (really_expand)
1241 expand_one_register_var (origvar);
1242 }
1243 else if (!host_integerp (DECL_SIZE_UNIT (var), 1))
1244 {
1245 if (really_expand)
1246 {
1247 error ("size of variable %q+D is too large", var);
1248 expand_one_error_var (var);
1249 }
1250 }
1251 else if (defer_stack_allocation (var, toplevel))
1252 add_stack_var (origvar);
1253 else
1254 {
1255 if (really_expand)
1256 expand_one_stack_var (origvar);
1257 return tree_low_cst (DECL_SIZE_UNIT (var), 1);
1258 }
1259 return 0;
1260 }
1261
1262 /* A subroutine of expand_used_vars. Walk down through the BLOCK tree
1263 expanding variables. Those variables that can be put into registers
1264 are allocated pseudos; those that can't are put on the stack.
1265
1266 TOPLEVEL is true if this is the outermost BLOCK. */
1267
1268 static void
expand_used_vars_for_block(tree block,bool toplevel)1269 expand_used_vars_for_block (tree block, bool toplevel)
1270 {
1271 tree t;
1272
1273 /* Expand all variables at this level. */
1274 for (t = BLOCK_VARS (block); t ; t = DECL_CHAIN (t))
1275 if (TREE_USED (t)
1276 && ((TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != RESULT_DECL)
1277 || !DECL_NONSHAREABLE (t)))
1278 expand_one_var (t, toplevel, true);
1279
1280 /* Expand all variables at containing levels. */
1281 for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t))
1282 expand_used_vars_for_block (t, false);
1283 }
1284
1285 /* A subroutine of expand_used_vars. Walk down through the BLOCK tree
1286 and clear TREE_USED on all local variables. */
1287
1288 static void
clear_tree_used(tree block)1289 clear_tree_used (tree block)
1290 {
1291 tree t;
1292
1293 for (t = BLOCK_VARS (block); t ; t = DECL_CHAIN (t))
1294 /* if (!TREE_STATIC (t) && !DECL_EXTERNAL (t)) */
1295 if ((TREE_CODE (t) != VAR_DECL && TREE_CODE (t) != RESULT_DECL)
1296 || !DECL_NONSHAREABLE (t))
1297 TREE_USED (t) = 0;
1298
1299 for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t))
1300 clear_tree_used (t);
1301 }
1302
1303 /* Examine TYPE and determine a bit mask of the following features. */
1304
1305 #define SPCT_HAS_LARGE_CHAR_ARRAY 1
1306 #define SPCT_HAS_SMALL_CHAR_ARRAY 2
1307 #define SPCT_HAS_ARRAY 4
1308 #define SPCT_HAS_AGGREGATE 8
1309
1310 static unsigned int
stack_protect_classify_type(tree type)1311 stack_protect_classify_type (tree type)
1312 {
1313 unsigned int ret = 0;
1314 tree t;
1315
1316 switch (TREE_CODE (type))
1317 {
1318 case ARRAY_TYPE:
1319 t = TYPE_MAIN_VARIANT (TREE_TYPE (type));
1320 if (t == char_type_node
1321 || t == signed_char_type_node
1322 || t == unsigned_char_type_node)
1323 {
1324 unsigned HOST_WIDE_INT max = PARAM_VALUE (PARAM_SSP_BUFFER_SIZE);
1325 unsigned HOST_WIDE_INT len;
1326
1327 if (!TYPE_SIZE_UNIT (type)
1328 || !host_integerp (TYPE_SIZE_UNIT (type), 1))
1329 len = max;
1330 else
1331 len = tree_low_cst (TYPE_SIZE_UNIT (type), 1);
1332
1333 if (len < max)
1334 ret = SPCT_HAS_SMALL_CHAR_ARRAY | SPCT_HAS_ARRAY;
1335 else
1336 ret = SPCT_HAS_LARGE_CHAR_ARRAY | SPCT_HAS_ARRAY;
1337 }
1338 else
1339 ret = SPCT_HAS_ARRAY;
1340 break;
1341
1342 case UNION_TYPE:
1343 case QUAL_UNION_TYPE:
1344 case RECORD_TYPE:
1345 ret = SPCT_HAS_AGGREGATE;
1346 for (t = TYPE_FIELDS (type); t ; t = TREE_CHAIN (t))
1347 if (TREE_CODE (t) == FIELD_DECL)
1348 ret |= stack_protect_classify_type (TREE_TYPE (t));
1349 break;
1350
1351 default:
1352 break;
1353 }
1354
1355 return ret;
1356 }
1357
1358 /* Return nonzero if DECL should be segregated into the "vulnerable" upper
1359 part of the local stack frame. Remember if we ever return nonzero for
1360 any variable in this function. The return value is the phase number in
1361 which the variable should be allocated. */
1362
1363 static int
stack_protect_decl_phase(tree decl)1364 stack_protect_decl_phase (tree decl)
1365 {
1366 unsigned int bits = stack_protect_classify_type (TREE_TYPE (decl));
1367 int ret = 0;
1368
1369 if (bits & SPCT_HAS_SMALL_CHAR_ARRAY)
1370 has_short_buffer = true;
1371
1372 if (flag_stack_protect == 2)
1373 {
1374 if ((bits & (SPCT_HAS_SMALL_CHAR_ARRAY | SPCT_HAS_LARGE_CHAR_ARRAY))
1375 && !(bits & SPCT_HAS_AGGREGATE))
1376 ret = 1;
1377 else if (bits & SPCT_HAS_ARRAY)
1378 ret = 2;
1379 }
1380 else
1381 ret = (bits & SPCT_HAS_LARGE_CHAR_ARRAY) != 0;
1382
1383 if (ret)
1384 has_protected_decls = true;
1385
1386 return ret;
1387 }
1388
1389 /* Two helper routines that check for phase 1 and phase 2. These are used
1390 as callbacks for expand_stack_vars. */
1391
1392 static bool
stack_protect_decl_phase_1(tree decl)1393 stack_protect_decl_phase_1 (tree decl)
1394 {
1395 return stack_protect_decl_phase (decl) == 1;
1396 }
1397
1398 static bool
stack_protect_decl_phase_2(tree decl)1399 stack_protect_decl_phase_2 (tree decl)
1400 {
1401 return stack_protect_decl_phase (decl) == 2;
1402 }
1403
1404 /* Ensure that variables in different stack protection phases conflict
1405 so that they are not merged and share the same stack slot. */
1406
1407 static void
add_stack_protection_conflicts(void)1408 add_stack_protection_conflicts (void)
1409 {
1410 size_t i, j, n = stack_vars_num;
1411 unsigned char *phase;
1412
1413 phase = XNEWVEC (unsigned char, n);
1414 for (i = 0; i < n; ++i)
1415 phase[i] = stack_protect_decl_phase (stack_vars[i].decl);
1416
1417 for (i = 0; i < n; ++i)
1418 {
1419 unsigned char ph_i = phase[i];
1420 for (j = 0; j < i; ++j)
1421 if (ph_i != phase[j])
1422 add_stack_var_conflict (i, j);
1423 }
1424
1425 XDELETEVEC (phase);
1426 }
1427
1428 /* Create a decl for the guard at the top of the stack frame. */
1429
1430 static void
create_stack_guard(void)1431 create_stack_guard (void)
1432 {
1433 tree guard = build_decl (DECL_SOURCE_LOCATION (current_function_decl),
1434 VAR_DECL, NULL, ptr_type_node);
1435 TREE_THIS_VOLATILE (guard) = 1;
1436 TREE_USED (guard) = 1;
1437 expand_one_stack_var (guard);
1438 crtl->stack_protect_guard = guard;
1439 }
1440
1441 /* Prepare for expanding variables. */
1442 static void
init_vars_expansion(void)1443 init_vars_expansion (void)
1444 {
1445 tree t;
1446 unsigned ix;
1447 /* Set TREE_USED on all variables in the local_decls. */
1448 FOR_EACH_LOCAL_DECL (cfun, ix, t)
1449 TREE_USED (t) = 1;
1450
1451 /* Clear TREE_USED on all variables associated with a block scope. */
1452 clear_tree_used (DECL_INITIAL (current_function_decl));
1453
1454 /* Initialize local stack smashing state. */
1455 has_protected_decls = false;
1456 has_short_buffer = false;
1457 }
1458
1459 /* Free up stack variable graph data. */
1460 static void
fini_vars_expansion(void)1461 fini_vars_expansion (void)
1462 {
1463 size_t i, n = stack_vars_num;
1464 for (i = 0; i < n; i++)
1465 BITMAP_FREE (stack_vars[i].conflicts);
1466 XDELETEVEC (stack_vars);
1467 XDELETEVEC (stack_vars_sorted);
1468 stack_vars = NULL;
1469 stack_vars_alloc = stack_vars_num = 0;
1470 pointer_map_destroy (decl_to_stack_part);
1471 decl_to_stack_part = NULL;
1472 }
1473
1474 /* Make a fair guess for the size of the stack frame of the function
1475 in NODE. This doesn't have to be exact, the result is only used in
1476 the inline heuristics. So we don't want to run the full stack var
1477 packing algorithm (which is quadratic in the number of stack vars).
1478 Instead, we calculate the total size of all stack vars. This turns
1479 out to be a pretty fair estimate -- packing of stack vars doesn't
1480 happen very often. */
1481
1482 HOST_WIDE_INT
estimated_stack_frame_size(struct cgraph_node * node)1483 estimated_stack_frame_size (struct cgraph_node *node)
1484 {
1485 HOST_WIDE_INT size = 0;
1486 size_t i;
1487 tree var;
1488 tree old_cur_fun_decl = current_function_decl;
1489 referenced_var_iterator rvi;
1490 struct function *fn = DECL_STRUCT_FUNCTION (node->decl);
1491
1492 current_function_decl = node->decl;
1493 push_cfun (fn);
1494
1495 gcc_checking_assert (gimple_referenced_vars (fn));
1496 FOR_EACH_REFERENCED_VAR (fn, var, rvi)
1497 size += expand_one_var (var, true, false);
1498
1499 if (stack_vars_num > 0)
1500 {
1501 /* Fake sorting the stack vars for account_stack_vars (). */
1502 stack_vars_sorted = XNEWVEC (size_t, stack_vars_num);
1503 for (i = 0; i < stack_vars_num; ++i)
1504 stack_vars_sorted[i] = i;
1505 size += account_stack_vars ();
1506 fini_vars_expansion ();
1507 }
1508 pop_cfun ();
1509 current_function_decl = old_cur_fun_decl;
1510 return size;
1511 }
1512
1513 /* Expand all variables used in the function. */
1514
1515 static void
expand_used_vars(void)1516 expand_used_vars (void)
1517 {
1518 tree var, outer_block = DECL_INITIAL (current_function_decl);
1519 VEC(tree,heap) *maybe_local_decls = NULL;
1520 unsigned i;
1521 unsigned len;
1522
1523 /* Compute the phase of the stack frame for this function. */
1524 {
1525 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1526 int off = STARTING_FRAME_OFFSET % align;
1527 frame_phase = off ? align - off : 0;
1528 }
1529
1530 init_vars_expansion ();
1531
1532 for (i = 0; i < SA.map->num_partitions; i++)
1533 {
1534 tree var = partition_to_var (SA.map, i);
1535
1536 gcc_assert (is_gimple_reg (var));
1537 if (TREE_CODE (SSA_NAME_VAR (var)) == VAR_DECL)
1538 expand_one_var (var, true, true);
1539 else
1540 {
1541 /* This is a PARM_DECL or RESULT_DECL. For those partitions that
1542 contain the default def (representing the parm or result itself)
1543 we don't do anything here. But those which don't contain the
1544 default def (representing a temporary based on the parm/result)
1545 we need to allocate space just like for normal VAR_DECLs. */
1546 if (!bitmap_bit_p (SA.partition_has_default_def, i))
1547 {
1548 expand_one_var (var, true, true);
1549 gcc_assert (SA.partition_to_pseudo[i]);
1550 }
1551 }
1552 }
1553
1554 /* At this point all variables on the local_decls with TREE_USED
1555 set are not associated with any block scope. Lay them out. */
1556
1557 len = VEC_length (tree, cfun->local_decls);
1558 FOR_EACH_LOCAL_DECL (cfun, i, var)
1559 {
1560 bool expand_now = false;
1561
1562 /* Expanded above already. */
1563 if (is_gimple_reg (var))
1564 {
1565 TREE_USED (var) = 0;
1566 goto next;
1567 }
1568 /* We didn't set a block for static or extern because it's hard
1569 to tell the difference between a global variable (re)declared
1570 in a local scope, and one that's really declared there to
1571 begin with. And it doesn't really matter much, since we're
1572 not giving them stack space. Expand them now. */
1573 else if (TREE_STATIC (var) || DECL_EXTERNAL (var))
1574 expand_now = true;
1575
1576 /* If the variable is not associated with any block, then it
1577 was created by the optimizers, and could be live anywhere
1578 in the function. */
1579 else if (TREE_USED (var))
1580 expand_now = true;
1581
1582 /* Finally, mark all variables on the list as used. We'll use
1583 this in a moment when we expand those associated with scopes. */
1584 TREE_USED (var) = 1;
1585
1586 if (expand_now)
1587 expand_one_var (var, true, true);
1588
1589 next:
1590 if (DECL_ARTIFICIAL (var) && !DECL_IGNORED_P (var))
1591 {
1592 rtx rtl = DECL_RTL_IF_SET (var);
1593
1594 /* Keep artificial non-ignored vars in cfun->local_decls
1595 chain until instantiate_decls. */
1596 if (rtl && (MEM_P (rtl) || GET_CODE (rtl) == CONCAT))
1597 add_local_decl (cfun, var);
1598 else if (rtl == NULL_RTX)
1599 /* If rtl isn't set yet, which can happen e.g. with
1600 -fstack-protector, retry before returning from this
1601 function. */
1602 VEC_safe_push (tree, heap, maybe_local_decls, var);
1603 }
1604 }
1605
1606 /* We duplicated some of the decls in CFUN->LOCAL_DECLS.
1607
1608 +-----------------+-----------------+
1609 | ...processed... | ...duplicates...|
1610 +-----------------+-----------------+
1611 ^
1612 +-- LEN points here.
1613
1614 We just want the duplicates, as those are the artificial
1615 non-ignored vars that we want to keep until instantiate_decls.
1616 Move them down and truncate the array. */
1617 if (!VEC_empty (tree, cfun->local_decls))
1618 VEC_block_remove (tree, cfun->local_decls, 0, len);
1619
1620 /* At this point, all variables within the block tree with TREE_USED
1621 set are actually used by the optimized function. Lay them out. */
1622 expand_used_vars_for_block (outer_block, true);
1623
1624 if (stack_vars_num > 0)
1625 {
1626 add_scope_conflicts ();
1627 /* Due to the way alias sets work, no variables with non-conflicting
1628 alias sets may be assigned the same address. Add conflicts to
1629 reflect this. */
1630 add_alias_set_conflicts ();
1631
1632 /* If stack protection is enabled, we don't share space between
1633 vulnerable data and non-vulnerable data. */
1634 if (flag_stack_protect)
1635 add_stack_protection_conflicts ();
1636
1637 /* Now that we have collected all stack variables, and have computed a
1638 minimal interference graph, attempt to save some stack space. */
1639 partition_stack_vars ();
1640 if (dump_file)
1641 dump_stack_var_partition ();
1642 }
1643
1644 /* There are several conditions under which we should create a
1645 stack guard: protect-all, alloca used, protected decls present. */
1646 if (flag_stack_protect == 2
1647 || (flag_stack_protect
1648 && (cfun->calls_alloca || has_protected_decls)))
1649 create_stack_guard ();
1650
1651 /* Assign rtl to each variable based on these partitions. */
1652 if (stack_vars_num > 0)
1653 {
1654 /* Reorder decls to be protected by iterating over the variables
1655 array multiple times, and allocating out of each phase in turn. */
1656 /* ??? We could probably integrate this into the qsort we did
1657 earlier, such that we naturally see these variables first,
1658 and thus naturally allocate things in the right order. */
1659 if (has_protected_decls)
1660 {
1661 /* Phase 1 contains only character arrays. */
1662 expand_stack_vars (stack_protect_decl_phase_1);
1663
1664 /* Phase 2 contains other kinds of arrays. */
1665 if (flag_stack_protect == 2)
1666 expand_stack_vars (stack_protect_decl_phase_2);
1667 }
1668
1669 expand_stack_vars (NULL);
1670
1671 fini_vars_expansion ();
1672 }
1673
1674 /* If there were any artificial non-ignored vars without rtl
1675 found earlier, see if deferred stack allocation hasn't assigned
1676 rtl to them. */
1677 FOR_EACH_VEC_ELT_REVERSE (tree, maybe_local_decls, i, var)
1678 {
1679 rtx rtl = DECL_RTL_IF_SET (var);
1680
1681 /* Keep artificial non-ignored vars in cfun->local_decls
1682 chain until instantiate_decls. */
1683 if (rtl && (MEM_P (rtl) || GET_CODE (rtl) == CONCAT))
1684 add_local_decl (cfun, var);
1685 }
1686 VEC_free (tree, heap, maybe_local_decls);
1687
1688 /* If the target requires that FRAME_OFFSET be aligned, do it. */
1689 if (STACK_ALIGNMENT_NEEDED)
1690 {
1691 HOST_WIDE_INT align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1692 if (!FRAME_GROWS_DOWNWARD)
1693 frame_offset += align - 1;
1694 frame_offset &= -align;
1695 }
1696 }
1697
1698
1699 /* If we need to produce a detailed dump, print the tree representation
1700 for STMT to the dump file. SINCE is the last RTX after which the RTL
1701 generated for STMT should have been appended. */
1702
1703 static void
maybe_dump_rtl_for_gimple_stmt(gimple stmt,rtx since)1704 maybe_dump_rtl_for_gimple_stmt (gimple stmt, rtx since)
1705 {
1706 if (dump_file && (dump_flags & TDF_DETAILS))
1707 {
1708 fprintf (dump_file, "\n;; ");
1709 print_gimple_stmt (dump_file, stmt, 0,
1710 TDF_SLIM | (dump_flags & TDF_LINENO));
1711 fprintf (dump_file, "\n");
1712
1713 print_rtl (dump_file, since ? NEXT_INSN (since) : since);
1714 }
1715 }
1716
1717 /* Maps the blocks that do not contain tree labels to rtx labels. */
1718
1719 static struct pointer_map_t *lab_rtx_for_bb;
1720
1721 /* Returns the label_rtx expression for a label starting basic block BB. */
1722
1723 static rtx
label_rtx_for_bb(basic_block bb ATTRIBUTE_UNUSED)1724 label_rtx_for_bb (basic_block bb ATTRIBUTE_UNUSED)
1725 {
1726 gimple_stmt_iterator gsi;
1727 tree lab;
1728 gimple lab_stmt;
1729 void **elt;
1730
1731 if (bb->flags & BB_RTL)
1732 return block_label (bb);
1733
1734 elt = pointer_map_contains (lab_rtx_for_bb, bb);
1735 if (elt)
1736 return (rtx) *elt;
1737
1738 /* Find the tree label if it is present. */
1739
1740 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1741 {
1742 lab_stmt = gsi_stmt (gsi);
1743 if (gimple_code (lab_stmt) != GIMPLE_LABEL)
1744 break;
1745
1746 lab = gimple_label_label (lab_stmt);
1747 if (DECL_NONLOCAL (lab))
1748 break;
1749
1750 return label_rtx (lab);
1751 }
1752
1753 elt = pointer_map_insert (lab_rtx_for_bb, bb);
1754 *elt = gen_label_rtx ();
1755 return (rtx) *elt;
1756 }
1757
1758
1759 /* A subroutine of expand_gimple_cond. Given E, a fallthrough edge
1760 of a basic block where we just expanded the conditional at the end,
1761 possibly clean up the CFG and instruction sequence. LAST is the
1762 last instruction before the just emitted jump sequence. */
1763
1764 static void
maybe_cleanup_end_of_block(edge e,rtx last)1765 maybe_cleanup_end_of_block (edge e, rtx last)
1766 {
1767 /* Special case: when jumpif decides that the condition is
1768 trivial it emits an unconditional jump (and the necessary
1769 barrier). But we still have two edges, the fallthru one is
1770 wrong. purge_dead_edges would clean this up later. Unfortunately
1771 we have to insert insns (and split edges) before
1772 find_many_sub_basic_blocks and hence before purge_dead_edges.
1773 But splitting edges might create new blocks which depend on the
1774 fact that if there are two edges there's no barrier. So the
1775 barrier would get lost and verify_flow_info would ICE. Instead
1776 of auditing all edge splitters to care for the barrier (which
1777 normally isn't there in a cleaned CFG), fix it here. */
1778 if (BARRIER_P (get_last_insn ()))
1779 {
1780 rtx insn;
1781 remove_edge (e);
1782 /* Now, we have a single successor block, if we have insns to
1783 insert on the remaining edge we potentially will insert
1784 it at the end of this block (if the dest block isn't feasible)
1785 in order to avoid splitting the edge. This insertion will take
1786 place in front of the last jump. But we might have emitted
1787 multiple jumps (conditional and one unconditional) to the
1788 same destination. Inserting in front of the last one then
1789 is a problem. See PR 40021. We fix this by deleting all
1790 jumps except the last unconditional one. */
1791 insn = PREV_INSN (get_last_insn ());
1792 /* Make sure we have an unconditional jump. Otherwise we're
1793 confused. */
1794 gcc_assert (JUMP_P (insn) && !any_condjump_p (insn));
1795 for (insn = PREV_INSN (insn); insn != last;)
1796 {
1797 insn = PREV_INSN (insn);
1798 if (JUMP_P (NEXT_INSN (insn)))
1799 {
1800 if (!any_condjump_p (NEXT_INSN (insn)))
1801 {
1802 gcc_assert (BARRIER_P (NEXT_INSN (NEXT_INSN (insn))));
1803 delete_insn (NEXT_INSN (NEXT_INSN (insn)));
1804 }
1805 delete_insn (NEXT_INSN (insn));
1806 }
1807 }
1808 }
1809 }
1810
1811 /* A subroutine of expand_gimple_basic_block. Expand one GIMPLE_COND.
1812 Returns a new basic block if we've terminated the current basic
1813 block and created a new one. */
1814
1815 static basic_block
expand_gimple_cond(basic_block bb,gimple stmt)1816 expand_gimple_cond (basic_block bb, gimple stmt)
1817 {
1818 basic_block new_bb, dest;
1819 edge new_edge;
1820 edge true_edge;
1821 edge false_edge;
1822 rtx last2, last;
1823 enum tree_code code;
1824 tree op0, op1;
1825
1826 code = gimple_cond_code (stmt);
1827 op0 = gimple_cond_lhs (stmt);
1828 op1 = gimple_cond_rhs (stmt);
1829 /* We're sometimes presented with such code:
1830 D.123_1 = x < y;
1831 if (D.123_1 != 0)
1832 ...
1833 This would expand to two comparisons which then later might
1834 be cleaned up by combine. But some pattern matchers like if-conversion
1835 work better when there's only one compare, so make up for this
1836 here as special exception if TER would have made the same change. */
1837 if (gimple_cond_single_var_p (stmt)
1838 && SA.values
1839 && TREE_CODE (op0) == SSA_NAME
1840 && bitmap_bit_p (SA.values, SSA_NAME_VERSION (op0)))
1841 {
1842 gimple second = SSA_NAME_DEF_STMT (op0);
1843 if (gimple_code (second) == GIMPLE_ASSIGN)
1844 {
1845 enum tree_code code2 = gimple_assign_rhs_code (second);
1846 if (TREE_CODE_CLASS (code2) == tcc_comparison)
1847 {
1848 code = code2;
1849 op0 = gimple_assign_rhs1 (second);
1850 op1 = gimple_assign_rhs2 (second);
1851 }
1852 /* If jumps are cheap turn some more codes into
1853 jumpy sequences. */
1854 else if (BRANCH_COST (optimize_insn_for_speed_p (), false) < 4)
1855 {
1856 if ((code2 == BIT_AND_EXPR
1857 && TYPE_PRECISION (TREE_TYPE (op0)) == 1
1858 && TREE_CODE (gimple_assign_rhs2 (second)) != INTEGER_CST)
1859 || code2 == TRUTH_AND_EXPR)
1860 {
1861 code = TRUTH_ANDIF_EXPR;
1862 op0 = gimple_assign_rhs1 (second);
1863 op1 = gimple_assign_rhs2 (second);
1864 }
1865 else if (code2 == BIT_IOR_EXPR || code2 == TRUTH_OR_EXPR)
1866 {
1867 code = TRUTH_ORIF_EXPR;
1868 op0 = gimple_assign_rhs1 (second);
1869 op1 = gimple_assign_rhs2 (second);
1870 }
1871 }
1872 }
1873 }
1874
1875 last2 = last = get_last_insn ();
1876
1877 extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
1878 set_curr_insn_source_location (gimple_location (stmt));
1879 set_curr_insn_block (gimple_block (stmt));
1880
1881 /* These flags have no purpose in RTL land. */
1882 true_edge->flags &= ~EDGE_TRUE_VALUE;
1883 false_edge->flags &= ~EDGE_FALSE_VALUE;
1884
1885 /* We can either have a pure conditional jump with one fallthru edge or
1886 two-way jump that needs to be decomposed into two basic blocks. */
1887 if (false_edge->dest == bb->next_bb)
1888 {
1889 jumpif_1 (code, op0, op1, label_rtx_for_bb (true_edge->dest),
1890 true_edge->probability);
1891 maybe_dump_rtl_for_gimple_stmt (stmt, last);
1892 if (true_edge->goto_locus)
1893 {
1894 set_curr_insn_source_location (true_edge->goto_locus);
1895 set_curr_insn_block (true_edge->goto_block);
1896 true_edge->goto_locus = curr_insn_locator ();
1897 }
1898 true_edge->goto_block = NULL;
1899 false_edge->flags |= EDGE_FALLTHRU;
1900 maybe_cleanup_end_of_block (false_edge, last);
1901 return NULL;
1902 }
1903 if (true_edge->dest == bb->next_bb)
1904 {
1905 jumpifnot_1 (code, op0, op1, label_rtx_for_bb (false_edge->dest),
1906 false_edge->probability);
1907 maybe_dump_rtl_for_gimple_stmt (stmt, last);
1908 if (false_edge->goto_locus)
1909 {
1910 set_curr_insn_source_location (false_edge->goto_locus);
1911 set_curr_insn_block (false_edge->goto_block);
1912 false_edge->goto_locus = curr_insn_locator ();
1913 }
1914 false_edge->goto_block = NULL;
1915 true_edge->flags |= EDGE_FALLTHRU;
1916 maybe_cleanup_end_of_block (true_edge, last);
1917 return NULL;
1918 }
1919
1920 jumpif_1 (code, op0, op1, label_rtx_for_bb (true_edge->dest),
1921 true_edge->probability);
1922 last = get_last_insn ();
1923 if (false_edge->goto_locus)
1924 {
1925 set_curr_insn_source_location (false_edge->goto_locus);
1926 set_curr_insn_block (false_edge->goto_block);
1927 false_edge->goto_locus = curr_insn_locator ();
1928 }
1929 false_edge->goto_block = NULL;
1930 emit_jump (label_rtx_for_bb (false_edge->dest));
1931
1932 BB_END (bb) = last;
1933 if (BARRIER_P (BB_END (bb)))
1934 BB_END (bb) = PREV_INSN (BB_END (bb));
1935 update_bb_for_insn (bb);
1936
1937 new_bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb);
1938 dest = false_edge->dest;
1939 redirect_edge_succ (false_edge, new_bb);
1940 false_edge->flags |= EDGE_FALLTHRU;
1941 new_bb->count = false_edge->count;
1942 new_bb->frequency = EDGE_FREQUENCY (false_edge);
1943 new_edge = make_edge (new_bb, dest, 0);
1944 new_edge->probability = REG_BR_PROB_BASE;
1945 new_edge->count = new_bb->count;
1946 if (BARRIER_P (BB_END (new_bb)))
1947 BB_END (new_bb) = PREV_INSN (BB_END (new_bb));
1948 update_bb_for_insn (new_bb);
1949
1950 maybe_dump_rtl_for_gimple_stmt (stmt, last2);
1951
1952 if (true_edge->goto_locus)
1953 {
1954 set_curr_insn_source_location (true_edge->goto_locus);
1955 set_curr_insn_block (true_edge->goto_block);
1956 true_edge->goto_locus = curr_insn_locator ();
1957 }
1958 true_edge->goto_block = NULL;
1959
1960 return new_bb;
1961 }
1962
1963 /* Mark all calls that can have a transaction restart. */
1964
1965 static void
mark_transaction_restart_calls(gimple stmt)1966 mark_transaction_restart_calls (gimple stmt)
1967 {
1968 struct tm_restart_node dummy;
1969 void **slot;
1970
1971 if (!cfun->gimple_df->tm_restart)
1972 return;
1973
1974 dummy.stmt = stmt;
1975 slot = htab_find_slot (cfun->gimple_df->tm_restart, &dummy, NO_INSERT);
1976 if (slot)
1977 {
1978 struct tm_restart_node *n = (struct tm_restart_node *) *slot;
1979 tree list = n->label_or_list;
1980 rtx insn;
1981
1982 for (insn = next_real_insn (get_last_insn ());
1983 !CALL_P (insn);
1984 insn = next_real_insn (insn))
1985 continue;
1986
1987 if (TREE_CODE (list) == LABEL_DECL)
1988 add_reg_note (insn, REG_TM, label_rtx (list));
1989 else
1990 for (; list ; list = TREE_CHAIN (list))
1991 add_reg_note (insn, REG_TM, label_rtx (TREE_VALUE (list)));
1992 }
1993 }
1994
1995 /* A subroutine of expand_gimple_stmt_1, expanding one GIMPLE_CALL
1996 statement STMT. */
1997
1998 static void
expand_call_stmt(gimple stmt)1999 expand_call_stmt (gimple stmt)
2000 {
2001 tree exp, decl, lhs;
2002 bool builtin_p;
2003 size_t i;
2004
2005 if (gimple_call_internal_p (stmt))
2006 {
2007 expand_internal_call (stmt);
2008 return;
2009 }
2010
2011 exp = build_vl_exp (CALL_EXPR, gimple_call_num_args (stmt) + 3);
2012
2013 CALL_EXPR_FN (exp) = gimple_call_fn (stmt);
2014 decl = gimple_call_fndecl (stmt);
2015 builtin_p = decl && DECL_BUILT_IN (decl);
2016
2017 /* If this is not a builtin function, the function type through which the
2018 call is made may be different from the type of the function. */
2019 if (!builtin_p)
2020 CALL_EXPR_FN (exp)
2021 = fold_convert (build_pointer_type (gimple_call_fntype (stmt)),
2022 CALL_EXPR_FN (exp));
2023
2024 TREE_TYPE (exp) = gimple_call_return_type (stmt);
2025 CALL_EXPR_STATIC_CHAIN (exp) = gimple_call_chain (stmt);
2026
2027 for (i = 0; i < gimple_call_num_args (stmt); i++)
2028 {
2029 tree arg = gimple_call_arg (stmt, i);
2030 gimple def;
2031 /* TER addresses into arguments of builtin functions so we have a
2032 chance to infer more correct alignment information. See PR39954. */
2033 if (builtin_p
2034 && TREE_CODE (arg) == SSA_NAME
2035 && (def = get_gimple_for_ssa_name (arg))
2036 && gimple_assign_rhs_code (def) == ADDR_EXPR)
2037 arg = gimple_assign_rhs1 (def);
2038 CALL_EXPR_ARG (exp, i) = arg;
2039 }
2040
2041 if (gimple_has_side_effects (stmt))
2042 TREE_SIDE_EFFECTS (exp) = 1;
2043
2044 if (gimple_call_nothrow_p (stmt))
2045 TREE_NOTHROW (exp) = 1;
2046
2047 CALL_EXPR_TAILCALL (exp) = gimple_call_tail_p (stmt);
2048 CALL_EXPR_RETURN_SLOT_OPT (exp) = gimple_call_return_slot_opt_p (stmt);
2049 if (decl
2050 && DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2051 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2052 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2053 CALL_ALLOCA_FOR_VAR_P (exp) = gimple_call_alloca_for_var_p (stmt);
2054 else
2055 CALL_FROM_THUNK_P (exp) = gimple_call_from_thunk_p (stmt);
2056 CALL_EXPR_VA_ARG_PACK (exp) = gimple_call_va_arg_pack_p (stmt);
2057 SET_EXPR_LOCATION (exp, gimple_location (stmt));
2058 TREE_BLOCK (exp) = gimple_block (stmt);
2059
2060 /* Ensure RTL is created for debug args. */
2061 if (decl && DECL_HAS_DEBUG_ARGS_P (decl))
2062 {
2063 VEC(tree, gc) **debug_args = decl_debug_args_lookup (decl);
2064 unsigned int ix;
2065 tree dtemp;
2066
2067 if (debug_args)
2068 for (ix = 1; VEC_iterate (tree, *debug_args, ix, dtemp); ix += 2)
2069 {
2070 gcc_assert (TREE_CODE (dtemp) == DEBUG_EXPR_DECL);
2071 expand_debug_expr (dtemp);
2072 }
2073 }
2074
2075 lhs = gimple_call_lhs (stmt);
2076 if (lhs)
2077 expand_assignment (lhs, exp, false);
2078 else
2079 expand_expr_real_1 (exp, const0_rtx, VOIDmode, EXPAND_NORMAL, NULL);
2080
2081 mark_transaction_restart_calls (stmt);
2082 }
2083
2084 /* A subroutine of expand_gimple_stmt, expanding one gimple statement
2085 STMT that doesn't require special handling for outgoing edges. That
2086 is no tailcalls and no GIMPLE_COND. */
2087
2088 static void
expand_gimple_stmt_1(gimple stmt)2089 expand_gimple_stmt_1 (gimple stmt)
2090 {
2091 tree op0;
2092
2093 set_curr_insn_source_location (gimple_location (stmt));
2094 set_curr_insn_block (gimple_block (stmt));
2095
2096 switch (gimple_code (stmt))
2097 {
2098 case GIMPLE_GOTO:
2099 op0 = gimple_goto_dest (stmt);
2100 if (TREE_CODE (op0) == LABEL_DECL)
2101 expand_goto (op0);
2102 else
2103 expand_computed_goto (op0);
2104 break;
2105 case GIMPLE_LABEL:
2106 expand_label (gimple_label_label (stmt));
2107 break;
2108 case GIMPLE_NOP:
2109 case GIMPLE_PREDICT:
2110 break;
2111 case GIMPLE_SWITCH:
2112 expand_case (stmt);
2113 break;
2114 case GIMPLE_ASM:
2115 expand_asm_stmt (stmt);
2116 break;
2117 case GIMPLE_CALL:
2118 expand_call_stmt (stmt);
2119 break;
2120
2121 case GIMPLE_RETURN:
2122 op0 = gimple_return_retval (stmt);
2123
2124 if (op0 && op0 != error_mark_node)
2125 {
2126 tree result = DECL_RESULT (current_function_decl);
2127
2128 /* If we are not returning the current function's RESULT_DECL,
2129 build an assignment to it. */
2130 if (op0 != result)
2131 {
2132 /* I believe that a function's RESULT_DECL is unique. */
2133 gcc_assert (TREE_CODE (op0) != RESULT_DECL);
2134
2135 /* ??? We'd like to use simply expand_assignment here,
2136 but this fails if the value is of BLKmode but the return
2137 decl is a register. expand_return has special handling
2138 for this combination, which eventually should move
2139 to common code. See comments there. Until then, let's
2140 build a modify expression :-/ */
2141 op0 = build2 (MODIFY_EXPR, TREE_TYPE (result),
2142 result, op0);
2143 }
2144 }
2145 if (!op0)
2146 expand_null_return ();
2147 else
2148 expand_return (op0);
2149 break;
2150
2151 case GIMPLE_ASSIGN:
2152 {
2153 tree lhs = gimple_assign_lhs (stmt);
2154
2155 /* Tree expand used to fiddle with |= and &= of two bitfield
2156 COMPONENT_REFs here. This can't happen with gimple, the LHS
2157 of binary assigns must be a gimple reg. */
2158
2159 if (TREE_CODE (lhs) != SSA_NAME
2160 || get_gimple_rhs_class (gimple_expr_code (stmt))
2161 == GIMPLE_SINGLE_RHS)
2162 {
2163 tree rhs = gimple_assign_rhs1 (stmt);
2164 gcc_assert (get_gimple_rhs_class (gimple_expr_code (stmt))
2165 == GIMPLE_SINGLE_RHS);
2166 if (gimple_has_location (stmt) && CAN_HAVE_LOCATION_P (rhs))
2167 SET_EXPR_LOCATION (rhs, gimple_location (stmt));
2168 if (TREE_CLOBBER_P (rhs))
2169 /* This is a clobber to mark the going out of scope for
2170 this LHS. */
2171 ;
2172 else
2173 expand_assignment (lhs, rhs,
2174 gimple_assign_nontemporal_move_p (stmt));
2175 }
2176 else
2177 {
2178 rtx target, temp;
2179 bool nontemporal = gimple_assign_nontemporal_move_p (stmt);
2180 struct separate_ops ops;
2181 bool promoted = false;
2182
2183 target = expand_expr (lhs, NULL_RTX, VOIDmode, EXPAND_WRITE);
2184 if (GET_CODE (target) == SUBREG && SUBREG_PROMOTED_VAR_P (target))
2185 promoted = true;
2186
2187 ops.code = gimple_assign_rhs_code (stmt);
2188 ops.type = TREE_TYPE (lhs);
2189 switch (get_gimple_rhs_class (gimple_expr_code (stmt)))
2190 {
2191 case GIMPLE_TERNARY_RHS:
2192 ops.op2 = gimple_assign_rhs3 (stmt);
2193 /* Fallthru */
2194 case GIMPLE_BINARY_RHS:
2195 ops.op1 = gimple_assign_rhs2 (stmt);
2196 /* Fallthru */
2197 case GIMPLE_UNARY_RHS:
2198 ops.op0 = gimple_assign_rhs1 (stmt);
2199 break;
2200 default:
2201 gcc_unreachable ();
2202 }
2203 ops.location = gimple_location (stmt);
2204
2205 /* If we want to use a nontemporal store, force the value to
2206 register first. If we store into a promoted register,
2207 don't directly expand to target. */
2208 temp = nontemporal || promoted ? NULL_RTX : target;
2209 temp = expand_expr_real_2 (&ops, temp, GET_MODE (target),
2210 EXPAND_NORMAL);
2211
2212 if (temp == target)
2213 ;
2214 else if (promoted)
2215 {
2216 int unsignedp = SUBREG_PROMOTED_UNSIGNED_P (target);
2217 /* If TEMP is a VOIDmode constant, use convert_modes to make
2218 sure that we properly convert it. */
2219 if (CONSTANT_P (temp) && GET_MODE (temp) == VOIDmode)
2220 {
2221 temp = convert_modes (GET_MODE (target),
2222 TYPE_MODE (ops.type),
2223 temp, unsignedp);
2224 temp = convert_modes (GET_MODE (SUBREG_REG (target)),
2225 GET_MODE (target), temp, unsignedp);
2226 }
2227
2228 convert_move (SUBREG_REG (target), temp, unsignedp);
2229 }
2230 else if (nontemporal && emit_storent_insn (target, temp))
2231 ;
2232 else
2233 {
2234 temp = force_operand (temp, target);
2235 if (temp != target)
2236 emit_move_insn (target, temp);
2237 }
2238 }
2239 }
2240 break;
2241
2242 default:
2243 gcc_unreachable ();
2244 }
2245 }
2246
2247 /* Expand one gimple statement STMT and return the last RTL instruction
2248 before any of the newly generated ones.
2249
2250 In addition to generating the necessary RTL instructions this also
2251 sets REG_EH_REGION notes if necessary and sets the current source
2252 location for diagnostics. */
2253
2254 static rtx
expand_gimple_stmt(gimple stmt)2255 expand_gimple_stmt (gimple stmt)
2256 {
2257 location_t saved_location = input_location;
2258 rtx last = get_last_insn ();
2259 int lp_nr;
2260
2261 gcc_assert (cfun);
2262
2263 /* We need to save and restore the current source location so that errors
2264 discovered during expansion are emitted with the right location. But
2265 it would be better if the diagnostic routines used the source location
2266 embedded in the tree nodes rather than globals. */
2267 if (gimple_has_location (stmt))
2268 input_location = gimple_location (stmt);
2269
2270 expand_gimple_stmt_1 (stmt);
2271
2272 /* Free any temporaries used to evaluate this statement. */
2273 free_temp_slots ();
2274
2275 input_location = saved_location;
2276
2277 /* Mark all insns that may trap. */
2278 lp_nr = lookup_stmt_eh_lp (stmt);
2279 if (lp_nr)
2280 {
2281 rtx insn;
2282 for (insn = next_real_insn (last); insn;
2283 insn = next_real_insn (insn))
2284 {
2285 if (! find_reg_note (insn, REG_EH_REGION, NULL_RTX)
2286 /* If we want exceptions for non-call insns, any
2287 may_trap_p instruction may throw. */
2288 && GET_CODE (PATTERN (insn)) != CLOBBER
2289 && GET_CODE (PATTERN (insn)) != USE
2290 && insn_could_throw_p (insn))
2291 make_reg_eh_region_note (insn, 0, lp_nr);
2292 }
2293 }
2294
2295 return last;
2296 }
2297
2298 /* A subroutine of expand_gimple_basic_block. Expand one GIMPLE_CALL
2299 that has CALL_EXPR_TAILCALL set. Returns non-null if we actually
2300 generated a tail call (something that might be denied by the ABI
2301 rules governing the call; see calls.c).
2302
2303 Sets CAN_FALLTHRU if we generated a *conditional* tail call, and
2304 can still reach the rest of BB. The case here is __builtin_sqrt,
2305 where the NaN result goes through the external function (with a
2306 tailcall) and the normal result happens via a sqrt instruction. */
2307
2308 static basic_block
expand_gimple_tailcall(basic_block bb,gimple stmt,bool * can_fallthru)2309 expand_gimple_tailcall (basic_block bb, gimple stmt, bool *can_fallthru)
2310 {
2311 rtx last2, last;
2312 edge e;
2313 edge_iterator ei;
2314 int probability;
2315 gcov_type count;
2316
2317 last2 = last = expand_gimple_stmt (stmt);
2318
2319 for (last = NEXT_INSN (last); last; last = NEXT_INSN (last))
2320 if (CALL_P (last) && SIBLING_CALL_P (last))
2321 goto found;
2322
2323 maybe_dump_rtl_for_gimple_stmt (stmt, last2);
2324
2325 *can_fallthru = true;
2326 return NULL;
2327
2328 found:
2329 /* ??? Wouldn't it be better to just reset any pending stack adjust?
2330 Any instructions emitted here are about to be deleted. */
2331 do_pending_stack_adjust ();
2332
2333 /* Remove any non-eh, non-abnormal edges that don't go to exit. */
2334 /* ??? I.e. the fallthrough edge. HOWEVER! If there were to be
2335 EH or abnormal edges, we shouldn't have created a tail call in
2336 the first place. So it seems to me we should just be removing
2337 all edges here, or redirecting the existing fallthru edge to
2338 the exit block. */
2339
2340 probability = 0;
2341 count = 0;
2342
2343 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
2344 {
2345 if (!(e->flags & (EDGE_ABNORMAL | EDGE_EH)))
2346 {
2347 if (e->dest != EXIT_BLOCK_PTR)
2348 {
2349 e->dest->count -= e->count;
2350 e->dest->frequency -= EDGE_FREQUENCY (e);
2351 if (e->dest->count < 0)
2352 e->dest->count = 0;
2353 if (e->dest->frequency < 0)
2354 e->dest->frequency = 0;
2355 }
2356 count += e->count;
2357 probability += e->probability;
2358 remove_edge (e);
2359 }
2360 else
2361 ei_next (&ei);
2362 }
2363
2364 /* This is somewhat ugly: the call_expr expander often emits instructions
2365 after the sibcall (to perform the function return). These confuse the
2366 find_many_sub_basic_blocks code, so we need to get rid of these. */
2367 last = NEXT_INSN (last);
2368 gcc_assert (BARRIER_P (last));
2369
2370 *can_fallthru = false;
2371 while (NEXT_INSN (last))
2372 {
2373 /* For instance an sqrt builtin expander expands if with
2374 sibcall in the then and label for `else`. */
2375 if (LABEL_P (NEXT_INSN (last)))
2376 {
2377 *can_fallthru = true;
2378 break;
2379 }
2380 delete_insn (NEXT_INSN (last));
2381 }
2382
2383 e = make_edge (bb, EXIT_BLOCK_PTR, EDGE_ABNORMAL | EDGE_SIBCALL);
2384 e->probability += probability;
2385 e->count += count;
2386 BB_END (bb) = last;
2387 update_bb_for_insn (bb);
2388
2389 if (NEXT_INSN (last))
2390 {
2391 bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb);
2392
2393 last = BB_END (bb);
2394 if (BARRIER_P (last))
2395 BB_END (bb) = PREV_INSN (last);
2396 }
2397
2398 maybe_dump_rtl_for_gimple_stmt (stmt, last2);
2399
2400 return bb;
2401 }
2402
2403 /* Return the difference between the floor and the truncated result of
2404 a signed division by OP1 with remainder MOD. */
2405 static rtx
floor_sdiv_adjust(enum machine_mode mode,rtx mod,rtx op1)2406 floor_sdiv_adjust (enum machine_mode mode, rtx mod, rtx op1)
2407 {
2408 /* (mod != 0 ? (op1 / mod < 0 ? -1 : 0) : 0) */
2409 return gen_rtx_IF_THEN_ELSE
2410 (mode, gen_rtx_NE (BImode, mod, const0_rtx),
2411 gen_rtx_IF_THEN_ELSE
2412 (mode, gen_rtx_LT (BImode,
2413 gen_rtx_DIV (mode, op1, mod),
2414 const0_rtx),
2415 constm1_rtx, const0_rtx),
2416 const0_rtx);
2417 }
2418
2419 /* Return the difference between the ceil and the truncated result of
2420 a signed division by OP1 with remainder MOD. */
2421 static rtx
ceil_sdiv_adjust(enum machine_mode mode,rtx mod,rtx op1)2422 ceil_sdiv_adjust (enum machine_mode mode, rtx mod, rtx op1)
2423 {
2424 /* (mod != 0 ? (op1 / mod > 0 ? 1 : 0) : 0) */
2425 return gen_rtx_IF_THEN_ELSE
2426 (mode, gen_rtx_NE (BImode, mod, const0_rtx),
2427 gen_rtx_IF_THEN_ELSE
2428 (mode, gen_rtx_GT (BImode,
2429 gen_rtx_DIV (mode, op1, mod),
2430 const0_rtx),
2431 const1_rtx, const0_rtx),
2432 const0_rtx);
2433 }
2434
2435 /* Return the difference between the ceil and the truncated result of
2436 an unsigned division by OP1 with remainder MOD. */
2437 static rtx
ceil_udiv_adjust(enum machine_mode mode,rtx mod,rtx op1 ATTRIBUTE_UNUSED)2438 ceil_udiv_adjust (enum machine_mode mode, rtx mod, rtx op1 ATTRIBUTE_UNUSED)
2439 {
2440 /* (mod != 0 ? 1 : 0) */
2441 return gen_rtx_IF_THEN_ELSE
2442 (mode, gen_rtx_NE (BImode, mod, const0_rtx),
2443 const1_rtx, const0_rtx);
2444 }
2445
2446 /* Return the difference between the rounded and the truncated result
2447 of a signed division by OP1 with remainder MOD. Halfway cases are
2448 rounded away from zero, rather than to the nearest even number. */
2449 static rtx
round_sdiv_adjust(enum machine_mode mode,rtx mod,rtx op1)2450 round_sdiv_adjust (enum machine_mode mode, rtx mod, rtx op1)
2451 {
2452 /* (abs (mod) >= abs (op1) - abs (mod)
2453 ? (op1 / mod > 0 ? 1 : -1)
2454 : 0) */
2455 return gen_rtx_IF_THEN_ELSE
2456 (mode, gen_rtx_GE (BImode, gen_rtx_ABS (mode, mod),
2457 gen_rtx_MINUS (mode,
2458 gen_rtx_ABS (mode, op1),
2459 gen_rtx_ABS (mode, mod))),
2460 gen_rtx_IF_THEN_ELSE
2461 (mode, gen_rtx_GT (BImode,
2462 gen_rtx_DIV (mode, op1, mod),
2463 const0_rtx),
2464 const1_rtx, constm1_rtx),
2465 const0_rtx);
2466 }
2467
2468 /* Return the difference between the rounded and the truncated result
2469 of a unsigned division by OP1 with remainder MOD. Halfway cases
2470 are rounded away from zero, rather than to the nearest even
2471 number. */
2472 static rtx
round_udiv_adjust(enum machine_mode mode,rtx mod,rtx op1)2473 round_udiv_adjust (enum machine_mode mode, rtx mod, rtx op1)
2474 {
2475 /* (mod >= op1 - mod ? 1 : 0) */
2476 return gen_rtx_IF_THEN_ELSE
2477 (mode, gen_rtx_GE (BImode, mod,
2478 gen_rtx_MINUS (mode, op1, mod)),
2479 const1_rtx, const0_rtx);
2480 }
2481
2482 /* Convert X to MODE, that must be Pmode or ptr_mode, without emitting
2483 any rtl. */
2484
2485 static rtx
convert_debug_memory_address(enum machine_mode mode,rtx x,addr_space_t as)2486 convert_debug_memory_address (enum machine_mode mode, rtx x,
2487 addr_space_t as)
2488 {
2489 enum machine_mode xmode = GET_MODE (x);
2490
2491 #ifndef POINTERS_EXTEND_UNSIGNED
2492 gcc_assert (mode == Pmode
2493 || mode == targetm.addr_space.address_mode (as));
2494 gcc_assert (xmode == mode || xmode == VOIDmode);
2495 #else
2496 rtx temp;
2497
2498 gcc_assert (targetm.addr_space.valid_pointer_mode (mode, as));
2499
2500 if (GET_MODE (x) == mode || GET_MODE (x) == VOIDmode)
2501 return x;
2502
2503 if (GET_MODE_PRECISION (mode) < GET_MODE_PRECISION (xmode))
2504 x = simplify_gen_subreg (mode, x, xmode,
2505 subreg_lowpart_offset
2506 (mode, xmode));
2507 else if (POINTERS_EXTEND_UNSIGNED > 0)
2508 x = gen_rtx_ZERO_EXTEND (mode, x);
2509 else if (!POINTERS_EXTEND_UNSIGNED)
2510 x = gen_rtx_SIGN_EXTEND (mode, x);
2511 else
2512 {
2513 switch (GET_CODE (x))
2514 {
2515 case SUBREG:
2516 if ((SUBREG_PROMOTED_VAR_P (x)
2517 || (REG_P (SUBREG_REG (x)) && REG_POINTER (SUBREG_REG (x)))
2518 || (GET_CODE (SUBREG_REG (x)) == PLUS
2519 && REG_P (XEXP (SUBREG_REG (x), 0))
2520 && REG_POINTER (XEXP (SUBREG_REG (x), 0))
2521 && CONST_INT_P (XEXP (SUBREG_REG (x), 1))))
2522 && GET_MODE (SUBREG_REG (x)) == mode)
2523 return SUBREG_REG (x);
2524 break;
2525 case LABEL_REF:
2526 temp = gen_rtx_LABEL_REF (mode, XEXP (x, 0));
2527 LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x);
2528 return temp;
2529 case SYMBOL_REF:
2530 temp = shallow_copy_rtx (x);
2531 PUT_MODE (temp, mode);
2532 return temp;
2533 case CONST:
2534 temp = convert_debug_memory_address (mode, XEXP (x, 0), as);
2535 if (temp)
2536 temp = gen_rtx_CONST (mode, temp);
2537 return temp;
2538 case PLUS:
2539 case MINUS:
2540 if (CONST_INT_P (XEXP (x, 1)))
2541 {
2542 temp = convert_debug_memory_address (mode, XEXP (x, 0), as);
2543 if (temp)
2544 return gen_rtx_fmt_ee (GET_CODE (x), mode, temp, XEXP (x, 1));
2545 }
2546 break;
2547 default:
2548 break;
2549 }
2550 /* Don't know how to express ptr_extend as operation in debug info. */
2551 return NULL;
2552 }
2553 #endif /* POINTERS_EXTEND_UNSIGNED */
2554
2555 return x;
2556 }
2557
2558 /* Return an RTX equivalent to the value of the parameter DECL. */
2559
2560 static rtx
expand_debug_parm_decl(tree decl)2561 expand_debug_parm_decl (tree decl)
2562 {
2563 rtx incoming = DECL_INCOMING_RTL (decl);
2564
2565 if (incoming
2566 && GET_MODE (incoming) != BLKmode
2567 && ((REG_P (incoming) && HARD_REGISTER_P (incoming))
2568 || (MEM_P (incoming)
2569 && REG_P (XEXP (incoming, 0))
2570 && HARD_REGISTER_P (XEXP (incoming, 0)))))
2571 {
2572 rtx rtl = gen_rtx_ENTRY_VALUE (GET_MODE (incoming));
2573
2574 #ifdef HAVE_window_save
2575 /* DECL_INCOMING_RTL uses the INCOMING_REGNO of parameter registers.
2576 If the target machine has an explicit window save instruction, the
2577 actual entry value is the corresponding OUTGOING_REGNO instead. */
2578 if (REG_P (incoming)
2579 && OUTGOING_REGNO (REGNO (incoming)) != REGNO (incoming))
2580 incoming
2581 = gen_rtx_REG_offset (incoming, GET_MODE (incoming),
2582 OUTGOING_REGNO (REGNO (incoming)), 0);
2583 else if (MEM_P (incoming))
2584 {
2585 rtx reg = XEXP (incoming, 0);
2586 if (OUTGOING_REGNO (REGNO (reg)) != REGNO (reg))
2587 {
2588 reg = gen_raw_REG (GET_MODE (reg), OUTGOING_REGNO (REGNO (reg)));
2589 incoming = replace_equiv_address_nv (incoming, reg);
2590 }
2591 else
2592 incoming = copy_rtx (incoming);
2593 }
2594 #endif
2595
2596 ENTRY_VALUE_EXP (rtl) = incoming;
2597 return rtl;
2598 }
2599
2600 if (incoming
2601 && GET_MODE (incoming) != BLKmode
2602 && !TREE_ADDRESSABLE (decl)
2603 && MEM_P (incoming)
2604 && (XEXP (incoming, 0) == virtual_incoming_args_rtx
2605 || (GET_CODE (XEXP (incoming, 0)) == PLUS
2606 && XEXP (XEXP (incoming, 0), 0) == virtual_incoming_args_rtx
2607 && CONST_INT_P (XEXP (XEXP (incoming, 0), 1)))))
2608 return copy_rtx (incoming);
2609
2610 return NULL_RTX;
2611 }
2612
2613 /* Return an RTX equivalent to the value of the tree expression EXP. */
2614
2615 static rtx
expand_debug_expr(tree exp)2616 expand_debug_expr (tree exp)
2617 {
2618 rtx op0 = NULL_RTX, op1 = NULL_RTX, op2 = NULL_RTX;
2619 enum machine_mode mode = TYPE_MODE (TREE_TYPE (exp));
2620 enum machine_mode inner_mode = VOIDmode;
2621 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (exp));
2622 addr_space_t as;
2623
2624 switch (TREE_CODE_CLASS (TREE_CODE (exp)))
2625 {
2626 case tcc_expression:
2627 switch (TREE_CODE (exp))
2628 {
2629 case COND_EXPR:
2630 case DOT_PROD_EXPR:
2631 case WIDEN_MULT_PLUS_EXPR:
2632 case WIDEN_MULT_MINUS_EXPR:
2633 case FMA_EXPR:
2634 goto ternary;
2635
2636 case TRUTH_ANDIF_EXPR:
2637 case TRUTH_ORIF_EXPR:
2638 case TRUTH_AND_EXPR:
2639 case TRUTH_OR_EXPR:
2640 case TRUTH_XOR_EXPR:
2641 goto binary;
2642
2643 case TRUTH_NOT_EXPR:
2644 goto unary;
2645
2646 default:
2647 break;
2648 }
2649 break;
2650
2651 ternary:
2652 op2 = expand_debug_expr (TREE_OPERAND (exp, 2));
2653 if (!op2)
2654 return NULL_RTX;
2655 /* Fall through. */
2656
2657 binary:
2658 case tcc_binary:
2659 case tcc_comparison:
2660 op1 = expand_debug_expr (TREE_OPERAND (exp, 1));
2661 if (!op1)
2662 return NULL_RTX;
2663 /* Fall through. */
2664
2665 unary:
2666 case tcc_unary:
2667 inner_mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
2668 op0 = expand_debug_expr (TREE_OPERAND (exp, 0));
2669 if (!op0)
2670 return NULL_RTX;
2671 break;
2672
2673 case tcc_type:
2674 case tcc_statement:
2675 gcc_unreachable ();
2676
2677 case tcc_constant:
2678 case tcc_exceptional:
2679 case tcc_declaration:
2680 case tcc_reference:
2681 case tcc_vl_exp:
2682 break;
2683 }
2684
2685 switch (TREE_CODE (exp))
2686 {
2687 case STRING_CST:
2688 if (!lookup_constant_def (exp))
2689 {
2690 if (strlen (TREE_STRING_POINTER (exp)) + 1
2691 != (size_t) TREE_STRING_LENGTH (exp))
2692 return NULL_RTX;
2693 op0 = gen_rtx_CONST_STRING (Pmode, TREE_STRING_POINTER (exp));
2694 op0 = gen_rtx_MEM (BLKmode, op0);
2695 set_mem_attributes (op0, exp, 0);
2696 return op0;
2697 }
2698 /* Fall through... */
2699
2700 case INTEGER_CST:
2701 case REAL_CST:
2702 case FIXED_CST:
2703 op0 = expand_expr (exp, NULL_RTX, mode, EXPAND_INITIALIZER);
2704 return op0;
2705
2706 case COMPLEX_CST:
2707 gcc_assert (COMPLEX_MODE_P (mode));
2708 op0 = expand_debug_expr (TREE_REALPART (exp));
2709 op1 = expand_debug_expr (TREE_IMAGPART (exp));
2710 return gen_rtx_CONCAT (mode, op0, op1);
2711
2712 case DEBUG_EXPR_DECL:
2713 op0 = DECL_RTL_IF_SET (exp);
2714
2715 if (op0)
2716 return op0;
2717
2718 op0 = gen_rtx_DEBUG_EXPR (mode);
2719 DEBUG_EXPR_TREE_DECL (op0) = exp;
2720 SET_DECL_RTL (exp, op0);
2721
2722 return op0;
2723
2724 case VAR_DECL:
2725 case PARM_DECL:
2726 case FUNCTION_DECL:
2727 case LABEL_DECL:
2728 case CONST_DECL:
2729 case RESULT_DECL:
2730 op0 = DECL_RTL_IF_SET (exp);
2731
2732 /* This decl was probably optimized away. */
2733 if (!op0)
2734 {
2735 if (TREE_CODE (exp) != VAR_DECL
2736 || DECL_EXTERNAL (exp)
2737 || !TREE_STATIC (exp)
2738 || !DECL_NAME (exp)
2739 || DECL_HARD_REGISTER (exp)
2740 || DECL_IN_CONSTANT_POOL (exp)
2741 || mode == VOIDmode)
2742 return NULL;
2743
2744 op0 = make_decl_rtl_for_debug (exp);
2745 if (!MEM_P (op0)
2746 || GET_CODE (XEXP (op0, 0)) != SYMBOL_REF
2747 || SYMBOL_REF_DECL (XEXP (op0, 0)) != exp)
2748 return NULL;
2749 }
2750 else
2751 op0 = copy_rtx (op0);
2752
2753 if (GET_MODE (op0) == BLKmode
2754 /* If op0 is not BLKmode, but BLKmode is, adjust_mode
2755 below would ICE. While it is likely a FE bug,
2756 try to be robust here. See PR43166. */
2757 || mode == BLKmode
2758 || (mode == VOIDmode && GET_MODE (op0) != VOIDmode))
2759 {
2760 gcc_assert (MEM_P (op0));
2761 op0 = adjust_address_nv (op0, mode, 0);
2762 return op0;
2763 }
2764
2765 /* Fall through. */
2766
2767 adjust_mode:
2768 case PAREN_EXPR:
2769 case NOP_EXPR:
2770 case CONVERT_EXPR:
2771 {
2772 inner_mode = GET_MODE (op0);
2773
2774 if (mode == inner_mode)
2775 return op0;
2776
2777 if (inner_mode == VOIDmode)
2778 {
2779 if (TREE_CODE (exp) == SSA_NAME)
2780 inner_mode = TYPE_MODE (TREE_TYPE (exp));
2781 else
2782 inner_mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
2783 if (mode == inner_mode)
2784 return op0;
2785 }
2786
2787 if (FLOAT_MODE_P (mode) && FLOAT_MODE_P (inner_mode))
2788 {
2789 if (GET_MODE_BITSIZE (mode) == GET_MODE_BITSIZE (inner_mode))
2790 op0 = simplify_gen_subreg (mode, op0, inner_mode, 0);
2791 else if (GET_MODE_BITSIZE (mode) < GET_MODE_BITSIZE (inner_mode))
2792 op0 = simplify_gen_unary (FLOAT_TRUNCATE, mode, op0, inner_mode);
2793 else
2794 op0 = simplify_gen_unary (FLOAT_EXTEND, mode, op0, inner_mode);
2795 }
2796 else if (FLOAT_MODE_P (mode))
2797 {
2798 gcc_assert (TREE_CODE (exp) != SSA_NAME);
2799 if (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0))))
2800 op0 = simplify_gen_unary (UNSIGNED_FLOAT, mode, op0, inner_mode);
2801 else
2802 op0 = simplify_gen_unary (FLOAT, mode, op0, inner_mode);
2803 }
2804 else if (FLOAT_MODE_P (inner_mode))
2805 {
2806 if (unsignedp)
2807 op0 = simplify_gen_unary (UNSIGNED_FIX, mode, op0, inner_mode);
2808 else
2809 op0 = simplify_gen_unary (FIX, mode, op0, inner_mode);
2810 }
2811 else if (CONSTANT_P (op0)
2812 || GET_MODE_PRECISION (mode) <= GET_MODE_PRECISION (inner_mode))
2813 op0 = simplify_gen_subreg (mode, op0, inner_mode,
2814 subreg_lowpart_offset (mode,
2815 inner_mode));
2816 else if (TREE_CODE_CLASS (TREE_CODE (exp)) == tcc_unary
2817 ? TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0)))
2818 : unsignedp)
2819 op0 = simplify_gen_unary (ZERO_EXTEND, mode, op0, inner_mode);
2820 else
2821 op0 = simplify_gen_unary (SIGN_EXTEND, mode, op0, inner_mode);
2822
2823 return op0;
2824 }
2825
2826 case MEM_REF:
2827 if (!is_gimple_mem_ref_addr (TREE_OPERAND (exp, 0)))
2828 {
2829 tree newexp = fold_binary (MEM_REF, TREE_TYPE (exp),
2830 TREE_OPERAND (exp, 0),
2831 TREE_OPERAND (exp, 1));
2832 if (newexp)
2833 return expand_debug_expr (newexp);
2834 }
2835 /* FALLTHROUGH */
2836 case INDIRECT_REF:
2837 op0 = expand_debug_expr (TREE_OPERAND (exp, 0));
2838 if (!op0)
2839 return NULL;
2840
2841 if (TREE_CODE (exp) == MEM_REF)
2842 {
2843 if (GET_CODE (op0) == DEBUG_IMPLICIT_PTR
2844 || (GET_CODE (op0) == PLUS
2845 && GET_CODE (XEXP (op0, 0)) == DEBUG_IMPLICIT_PTR))
2846 /* (mem (debug_implicit_ptr)) might confuse aliasing.
2847 Instead just use get_inner_reference. */
2848 goto component_ref;
2849
2850 op1 = expand_debug_expr (TREE_OPERAND (exp, 1));
2851 if (!op1 || !CONST_INT_P (op1))
2852 return NULL;
2853
2854 op0 = plus_constant (op0, INTVAL (op1));
2855 }
2856
2857 if (POINTER_TYPE_P (TREE_TYPE (exp)))
2858 as = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)));
2859 else
2860 as = ADDR_SPACE_GENERIC;
2861
2862 op0 = convert_debug_memory_address (targetm.addr_space.address_mode (as),
2863 op0, as);
2864 if (op0 == NULL_RTX)
2865 return NULL;
2866
2867 op0 = gen_rtx_MEM (mode, op0);
2868 set_mem_attributes (op0, exp, 0);
2869 if (TREE_CODE (exp) == MEM_REF
2870 && !is_gimple_mem_ref_addr (TREE_OPERAND (exp, 0)))
2871 set_mem_expr (op0, NULL_TREE);
2872 set_mem_addr_space (op0, as);
2873
2874 return op0;
2875
2876 case TARGET_MEM_REF:
2877 if (TREE_CODE (TMR_BASE (exp)) == ADDR_EXPR
2878 && !DECL_RTL_SET_P (TREE_OPERAND (TMR_BASE (exp), 0)))
2879 return NULL;
2880
2881 op0 = expand_debug_expr
2882 (tree_mem_ref_addr (build_pointer_type (TREE_TYPE (exp)), exp));
2883 if (!op0)
2884 return NULL;
2885
2886 if (POINTER_TYPE_P (TREE_TYPE (exp)))
2887 as = TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)));
2888 else
2889 as = ADDR_SPACE_GENERIC;
2890
2891 op0 = convert_debug_memory_address (targetm.addr_space.address_mode (as),
2892 op0, as);
2893 if (op0 == NULL_RTX)
2894 return NULL;
2895
2896 op0 = gen_rtx_MEM (mode, op0);
2897
2898 set_mem_attributes (op0, exp, 0);
2899 set_mem_addr_space (op0, as);
2900
2901 return op0;
2902
2903 component_ref:
2904 case ARRAY_REF:
2905 case ARRAY_RANGE_REF:
2906 case COMPONENT_REF:
2907 case BIT_FIELD_REF:
2908 case REALPART_EXPR:
2909 case IMAGPART_EXPR:
2910 case VIEW_CONVERT_EXPR:
2911 {
2912 enum machine_mode mode1;
2913 HOST_WIDE_INT bitsize, bitpos;
2914 tree offset;
2915 int volatilep = 0;
2916 tree tem = get_inner_reference (exp, &bitsize, &bitpos, &offset,
2917 &mode1, &unsignedp, &volatilep, false);
2918 rtx orig_op0;
2919
2920 if (bitsize == 0)
2921 return NULL;
2922
2923 orig_op0 = op0 = expand_debug_expr (tem);
2924
2925 if (!op0)
2926 return NULL;
2927
2928 if (offset)
2929 {
2930 enum machine_mode addrmode, offmode;
2931
2932 if (!MEM_P (op0))
2933 return NULL;
2934
2935 op0 = XEXP (op0, 0);
2936 addrmode = GET_MODE (op0);
2937 if (addrmode == VOIDmode)
2938 addrmode = Pmode;
2939
2940 op1 = expand_debug_expr (offset);
2941 if (!op1)
2942 return NULL;
2943
2944 offmode = GET_MODE (op1);
2945 if (offmode == VOIDmode)
2946 offmode = TYPE_MODE (TREE_TYPE (offset));
2947
2948 if (addrmode != offmode)
2949 op1 = simplify_gen_subreg (addrmode, op1, offmode,
2950 subreg_lowpart_offset (addrmode,
2951 offmode));
2952
2953 /* Don't use offset_address here, we don't need a
2954 recognizable address, and we don't want to generate
2955 code. */
2956 op0 = gen_rtx_MEM (mode, simplify_gen_binary (PLUS, addrmode,
2957 op0, op1));
2958 }
2959
2960 if (MEM_P (op0))
2961 {
2962 if (mode1 == VOIDmode)
2963 /* Bitfield. */
2964 mode1 = smallest_mode_for_size (bitsize, MODE_INT);
2965 if (bitpos >= BITS_PER_UNIT)
2966 {
2967 op0 = adjust_address_nv (op0, mode1, bitpos / BITS_PER_UNIT);
2968 bitpos %= BITS_PER_UNIT;
2969 }
2970 else if (bitpos < 0)
2971 {
2972 HOST_WIDE_INT units
2973 = (-bitpos + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
2974 op0 = adjust_address_nv (op0, mode1, units);
2975 bitpos += units * BITS_PER_UNIT;
2976 }
2977 else if (bitpos == 0 && bitsize == GET_MODE_BITSIZE (mode))
2978 op0 = adjust_address_nv (op0, mode, 0);
2979 else if (GET_MODE (op0) != mode1)
2980 op0 = adjust_address_nv (op0, mode1, 0);
2981 else
2982 op0 = copy_rtx (op0);
2983 if (op0 == orig_op0)
2984 op0 = shallow_copy_rtx (op0);
2985 set_mem_attributes (op0, exp, 0);
2986 }
2987
2988 if (bitpos == 0 && mode == GET_MODE (op0))
2989 return op0;
2990
2991 if (bitpos < 0)
2992 return NULL;
2993
2994 if (GET_MODE (op0) == BLKmode)
2995 return NULL;
2996
2997 if ((bitpos % BITS_PER_UNIT) == 0
2998 && bitsize == GET_MODE_BITSIZE (mode1))
2999 {
3000 enum machine_mode opmode = GET_MODE (op0);
3001
3002 if (opmode == VOIDmode)
3003 opmode = TYPE_MODE (TREE_TYPE (tem));
3004
3005 /* This condition may hold if we're expanding the address
3006 right past the end of an array that turned out not to
3007 be addressable (i.e., the address was only computed in
3008 debug stmts). The gen_subreg below would rightfully
3009 crash, and the address doesn't really exist, so just
3010 drop it. */
3011 if (bitpos >= GET_MODE_BITSIZE (opmode))
3012 return NULL;
3013
3014 if ((bitpos % GET_MODE_BITSIZE (mode)) == 0)
3015 return simplify_gen_subreg (mode, op0, opmode,
3016 bitpos / BITS_PER_UNIT);
3017 }
3018
3019 return simplify_gen_ternary (SCALAR_INT_MODE_P (GET_MODE (op0))
3020 && TYPE_UNSIGNED (TREE_TYPE (exp))
3021 ? SIGN_EXTRACT
3022 : ZERO_EXTRACT, mode,
3023 GET_MODE (op0) != VOIDmode
3024 ? GET_MODE (op0)
3025 : TYPE_MODE (TREE_TYPE (tem)),
3026 op0, GEN_INT (bitsize), GEN_INT (bitpos));
3027 }
3028
3029 case ABS_EXPR:
3030 return simplify_gen_unary (ABS, mode, op0, mode);
3031
3032 case NEGATE_EXPR:
3033 return simplify_gen_unary (NEG, mode, op0, mode);
3034
3035 case BIT_NOT_EXPR:
3036 return simplify_gen_unary (NOT, mode, op0, mode);
3037
3038 case FLOAT_EXPR:
3039 return simplify_gen_unary (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp,
3040 0)))
3041 ? UNSIGNED_FLOAT : FLOAT, mode, op0,
3042 inner_mode);
3043
3044 case FIX_TRUNC_EXPR:
3045 return simplify_gen_unary (unsignedp ? UNSIGNED_FIX : FIX, mode, op0,
3046 inner_mode);
3047
3048 case POINTER_PLUS_EXPR:
3049 /* For the rare target where pointers are not the same size as
3050 size_t, we need to check for mis-matched modes and correct
3051 the addend. */
3052 if (op0 && op1
3053 && GET_MODE (op0) != VOIDmode && GET_MODE (op1) != VOIDmode
3054 && GET_MODE (op0) != GET_MODE (op1))
3055 {
3056 if (GET_MODE_BITSIZE (GET_MODE (op0)) < GET_MODE_BITSIZE (GET_MODE (op1)))
3057 op1 = simplify_gen_unary (TRUNCATE, GET_MODE (op0), op1,
3058 GET_MODE (op1));
3059 else
3060 /* We always sign-extend, regardless of the signedness of
3061 the operand, because the operand is always unsigned
3062 here even if the original C expression is signed. */
3063 op1 = simplify_gen_unary (SIGN_EXTEND, GET_MODE (op0), op1,
3064 GET_MODE (op1));
3065 }
3066 /* Fall through. */
3067 case PLUS_EXPR:
3068 return simplify_gen_binary (PLUS, mode, op0, op1);
3069
3070 case MINUS_EXPR:
3071 return simplify_gen_binary (MINUS, mode, op0, op1);
3072
3073 case MULT_EXPR:
3074 return simplify_gen_binary (MULT, mode, op0, op1);
3075
3076 case RDIV_EXPR:
3077 case TRUNC_DIV_EXPR:
3078 case EXACT_DIV_EXPR:
3079 if (unsignedp)
3080 return simplify_gen_binary (UDIV, mode, op0, op1);
3081 else
3082 return simplify_gen_binary (DIV, mode, op0, op1);
3083
3084 case TRUNC_MOD_EXPR:
3085 return simplify_gen_binary (unsignedp ? UMOD : MOD, mode, op0, op1);
3086
3087 case FLOOR_DIV_EXPR:
3088 if (unsignedp)
3089 return simplify_gen_binary (UDIV, mode, op0, op1);
3090 else
3091 {
3092 rtx div = simplify_gen_binary (DIV, mode, op0, op1);
3093 rtx mod = simplify_gen_binary (MOD, mode, op0, op1);
3094 rtx adj = floor_sdiv_adjust (mode, mod, op1);
3095 return simplify_gen_binary (PLUS, mode, div, adj);
3096 }
3097
3098 case FLOOR_MOD_EXPR:
3099 if (unsignedp)
3100 return simplify_gen_binary (UMOD, mode, op0, op1);
3101 else
3102 {
3103 rtx mod = simplify_gen_binary (MOD, mode, op0, op1);
3104 rtx adj = floor_sdiv_adjust (mode, mod, op1);
3105 adj = simplify_gen_unary (NEG, mode,
3106 simplify_gen_binary (MULT, mode, adj, op1),
3107 mode);
3108 return simplify_gen_binary (PLUS, mode, mod, adj);
3109 }
3110
3111 case CEIL_DIV_EXPR:
3112 if (unsignedp)
3113 {
3114 rtx div = simplify_gen_binary (UDIV, mode, op0, op1);
3115 rtx mod = simplify_gen_binary (UMOD, mode, op0, op1);
3116 rtx adj = ceil_udiv_adjust (mode, mod, op1);
3117 return simplify_gen_binary (PLUS, mode, div, adj);
3118 }
3119 else
3120 {
3121 rtx div = simplify_gen_binary (DIV, mode, op0, op1);
3122 rtx mod = simplify_gen_binary (MOD, mode, op0, op1);
3123 rtx adj = ceil_sdiv_adjust (mode, mod, op1);
3124 return simplify_gen_binary (PLUS, mode, div, adj);
3125 }
3126
3127 case CEIL_MOD_EXPR:
3128 if (unsignedp)
3129 {
3130 rtx mod = simplify_gen_binary (UMOD, mode, op0, op1);
3131 rtx adj = ceil_udiv_adjust (mode, mod, op1);
3132 adj = simplify_gen_unary (NEG, mode,
3133 simplify_gen_binary (MULT, mode, adj, op1),
3134 mode);
3135 return simplify_gen_binary (PLUS, mode, mod, adj);
3136 }
3137 else
3138 {
3139 rtx mod = simplify_gen_binary (MOD, mode, op0, op1);
3140 rtx adj = ceil_sdiv_adjust (mode, mod, op1);
3141 adj = simplify_gen_unary (NEG, mode,
3142 simplify_gen_binary (MULT, mode, adj, op1),
3143 mode);
3144 return simplify_gen_binary (PLUS, mode, mod, adj);
3145 }
3146
3147 case ROUND_DIV_EXPR:
3148 if (unsignedp)
3149 {
3150 rtx div = simplify_gen_binary (UDIV, mode, op0, op1);
3151 rtx mod = simplify_gen_binary (UMOD, mode, op0, op1);
3152 rtx adj = round_udiv_adjust (mode, mod, op1);
3153 return simplify_gen_binary (PLUS, mode, div, adj);
3154 }
3155 else
3156 {
3157 rtx div = simplify_gen_binary (DIV, mode, op0, op1);
3158 rtx mod = simplify_gen_binary (MOD, mode, op0, op1);
3159 rtx adj = round_sdiv_adjust (mode, mod, op1);
3160 return simplify_gen_binary (PLUS, mode, div, adj);
3161 }
3162
3163 case ROUND_MOD_EXPR:
3164 if (unsignedp)
3165 {
3166 rtx mod = simplify_gen_binary (UMOD, mode, op0, op1);
3167 rtx adj = round_udiv_adjust (mode, mod, op1);
3168 adj = simplify_gen_unary (NEG, mode,
3169 simplify_gen_binary (MULT, mode, adj, op1),
3170 mode);
3171 return simplify_gen_binary (PLUS, mode, mod, adj);
3172 }
3173 else
3174 {
3175 rtx mod = simplify_gen_binary (MOD, mode, op0, op1);
3176 rtx adj = round_sdiv_adjust (mode, mod, op1);
3177 adj = simplify_gen_unary (NEG, mode,
3178 simplify_gen_binary (MULT, mode, adj, op1),
3179 mode);
3180 return simplify_gen_binary (PLUS, mode, mod, adj);
3181 }
3182
3183 case LSHIFT_EXPR:
3184 return simplify_gen_binary (ASHIFT, mode, op0, op1);
3185
3186 case RSHIFT_EXPR:
3187 if (unsignedp)
3188 return simplify_gen_binary (LSHIFTRT, mode, op0, op1);
3189 else
3190 return simplify_gen_binary (ASHIFTRT, mode, op0, op1);
3191
3192 case LROTATE_EXPR:
3193 return simplify_gen_binary (ROTATE, mode, op0, op1);
3194
3195 case RROTATE_EXPR:
3196 return simplify_gen_binary (ROTATERT, mode, op0, op1);
3197
3198 case MIN_EXPR:
3199 return simplify_gen_binary (unsignedp ? UMIN : SMIN, mode, op0, op1);
3200
3201 case MAX_EXPR:
3202 return simplify_gen_binary (unsignedp ? UMAX : SMAX, mode, op0, op1);
3203
3204 case BIT_AND_EXPR:
3205 case TRUTH_AND_EXPR:
3206 return simplify_gen_binary (AND, mode, op0, op1);
3207
3208 case BIT_IOR_EXPR:
3209 case TRUTH_OR_EXPR:
3210 return simplify_gen_binary (IOR, mode, op0, op1);
3211
3212 case BIT_XOR_EXPR:
3213 case TRUTH_XOR_EXPR:
3214 return simplify_gen_binary (XOR, mode, op0, op1);
3215
3216 case TRUTH_ANDIF_EXPR:
3217 return gen_rtx_IF_THEN_ELSE (mode, op0, op1, const0_rtx);
3218
3219 case TRUTH_ORIF_EXPR:
3220 return gen_rtx_IF_THEN_ELSE (mode, op0, const_true_rtx, op1);
3221
3222 case TRUTH_NOT_EXPR:
3223 return simplify_gen_relational (EQ, mode, inner_mode, op0, const0_rtx);
3224
3225 case LT_EXPR:
3226 return simplify_gen_relational (unsignedp ? LTU : LT, mode, inner_mode,
3227 op0, op1);
3228
3229 case LE_EXPR:
3230 return simplify_gen_relational (unsignedp ? LEU : LE, mode, inner_mode,
3231 op0, op1);
3232
3233 case GT_EXPR:
3234 return simplify_gen_relational (unsignedp ? GTU : GT, mode, inner_mode,
3235 op0, op1);
3236
3237 case GE_EXPR:
3238 return simplify_gen_relational (unsignedp ? GEU : GE, mode, inner_mode,
3239 op0, op1);
3240
3241 case EQ_EXPR:
3242 return simplify_gen_relational (EQ, mode, inner_mode, op0, op1);
3243
3244 case NE_EXPR:
3245 return simplify_gen_relational (NE, mode, inner_mode, op0, op1);
3246
3247 case UNORDERED_EXPR:
3248 return simplify_gen_relational (UNORDERED, mode, inner_mode, op0, op1);
3249
3250 case ORDERED_EXPR:
3251 return simplify_gen_relational (ORDERED, mode, inner_mode, op0, op1);
3252
3253 case UNLT_EXPR:
3254 return simplify_gen_relational (UNLT, mode, inner_mode, op0, op1);
3255
3256 case UNLE_EXPR:
3257 return simplify_gen_relational (UNLE, mode, inner_mode, op0, op1);
3258
3259 case UNGT_EXPR:
3260 return simplify_gen_relational (UNGT, mode, inner_mode, op0, op1);
3261
3262 case UNGE_EXPR:
3263 return simplify_gen_relational (UNGE, mode, inner_mode, op0, op1);
3264
3265 case UNEQ_EXPR:
3266 return simplify_gen_relational (UNEQ, mode, inner_mode, op0, op1);
3267
3268 case LTGT_EXPR:
3269 return simplify_gen_relational (LTGT, mode, inner_mode, op0, op1);
3270
3271 case COND_EXPR:
3272 return gen_rtx_IF_THEN_ELSE (mode, op0, op1, op2);
3273
3274 case COMPLEX_EXPR:
3275 gcc_assert (COMPLEX_MODE_P (mode));
3276 if (GET_MODE (op0) == VOIDmode)
3277 op0 = gen_rtx_CONST (GET_MODE_INNER (mode), op0);
3278 if (GET_MODE (op1) == VOIDmode)
3279 op1 = gen_rtx_CONST (GET_MODE_INNER (mode), op1);
3280 return gen_rtx_CONCAT (mode, op0, op1);
3281
3282 case CONJ_EXPR:
3283 if (GET_CODE (op0) == CONCAT)
3284 return gen_rtx_CONCAT (mode, XEXP (op0, 0),
3285 simplify_gen_unary (NEG, GET_MODE_INNER (mode),
3286 XEXP (op0, 1),
3287 GET_MODE_INNER (mode)));
3288 else
3289 {
3290 enum machine_mode imode = GET_MODE_INNER (mode);
3291 rtx re, im;
3292
3293 if (MEM_P (op0))
3294 {
3295 re = adjust_address_nv (op0, imode, 0);
3296 im = adjust_address_nv (op0, imode, GET_MODE_SIZE (imode));
3297 }
3298 else
3299 {
3300 enum machine_mode ifmode = int_mode_for_mode (mode);
3301 enum machine_mode ihmode = int_mode_for_mode (imode);
3302 rtx halfsize;
3303 if (ifmode == BLKmode || ihmode == BLKmode)
3304 return NULL;
3305 halfsize = GEN_INT (GET_MODE_BITSIZE (ihmode));
3306 re = op0;
3307 if (mode != ifmode)
3308 re = gen_rtx_SUBREG (ifmode, re, 0);
3309 re = gen_rtx_ZERO_EXTRACT (ihmode, re, halfsize, const0_rtx);
3310 if (imode != ihmode)
3311 re = gen_rtx_SUBREG (imode, re, 0);
3312 im = copy_rtx (op0);
3313 if (mode != ifmode)
3314 im = gen_rtx_SUBREG (ifmode, im, 0);
3315 im = gen_rtx_ZERO_EXTRACT (ihmode, im, halfsize, halfsize);
3316 if (imode != ihmode)
3317 im = gen_rtx_SUBREG (imode, im, 0);
3318 }
3319 im = gen_rtx_NEG (imode, im);
3320 return gen_rtx_CONCAT (mode, re, im);
3321 }
3322
3323 case ADDR_EXPR:
3324 op0 = expand_debug_expr (TREE_OPERAND (exp, 0));
3325 if (!op0 || !MEM_P (op0))
3326 {
3327 if ((TREE_CODE (TREE_OPERAND (exp, 0)) == VAR_DECL
3328 || TREE_CODE (TREE_OPERAND (exp, 0)) == PARM_DECL
3329 || TREE_CODE (TREE_OPERAND (exp, 0)) == RESULT_DECL)
3330 && (!TREE_ADDRESSABLE (TREE_OPERAND (exp, 0))
3331 || target_for_debug_bind (TREE_OPERAND (exp, 0))))
3332 return gen_rtx_DEBUG_IMPLICIT_PTR (mode, TREE_OPERAND (exp, 0));
3333
3334 if (handled_component_p (TREE_OPERAND (exp, 0)))
3335 {
3336 HOST_WIDE_INT bitoffset, bitsize, maxsize;
3337 tree decl
3338 = get_ref_base_and_extent (TREE_OPERAND (exp, 0),
3339 &bitoffset, &bitsize, &maxsize);
3340 if ((TREE_CODE (decl) == VAR_DECL
3341 || TREE_CODE (decl) == PARM_DECL
3342 || TREE_CODE (decl) == RESULT_DECL)
3343 && (!TREE_ADDRESSABLE (decl)
3344 || target_for_debug_bind (decl))
3345 && (bitoffset % BITS_PER_UNIT) == 0
3346 && bitsize > 0
3347 && bitsize == maxsize)
3348 return plus_constant (gen_rtx_DEBUG_IMPLICIT_PTR (mode, decl),
3349 bitoffset / BITS_PER_UNIT);
3350 }
3351
3352 return NULL;
3353 }
3354
3355 as = TYPE_ADDR_SPACE (TREE_TYPE (exp));
3356 op0 = convert_debug_memory_address (mode, XEXP (op0, 0), as);
3357
3358 return op0;
3359
3360 case VECTOR_CST:
3361 exp = build_constructor_from_list (TREE_TYPE (exp),
3362 TREE_VECTOR_CST_ELTS (exp));
3363 /* Fall through. */
3364
3365 case CONSTRUCTOR:
3366 if (TREE_CLOBBER_P (exp))
3367 return NULL;
3368 else if (TREE_CODE (TREE_TYPE (exp)) == VECTOR_TYPE)
3369 {
3370 unsigned i;
3371 tree val;
3372
3373 op0 = gen_rtx_CONCATN
3374 (mode, rtvec_alloc (TYPE_VECTOR_SUBPARTS (TREE_TYPE (exp))));
3375
3376 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), i, val)
3377 {
3378 op1 = expand_debug_expr (val);
3379 if (!op1)
3380 return NULL;
3381 XVECEXP (op0, 0, i) = op1;
3382 }
3383
3384 if (i < TYPE_VECTOR_SUBPARTS (TREE_TYPE (exp)))
3385 {
3386 op1 = expand_debug_expr
3387 (build_zero_cst (TREE_TYPE (TREE_TYPE (exp))));
3388
3389 if (!op1)
3390 return NULL;
3391
3392 for (; i < TYPE_VECTOR_SUBPARTS (TREE_TYPE (exp)); i++)
3393 XVECEXP (op0, 0, i) = op1;
3394 }
3395
3396 return op0;
3397 }
3398 else
3399 goto flag_unsupported;
3400
3401 case CALL_EXPR:
3402 /* ??? Maybe handle some builtins? */
3403 return NULL;
3404
3405 case SSA_NAME:
3406 {
3407 gimple g = get_gimple_for_ssa_name (exp);
3408 if (g)
3409 {
3410 op0 = expand_debug_expr (gimple_assign_rhs_to_tree (g));
3411 if (!op0)
3412 return NULL;
3413 }
3414 else
3415 {
3416 int part = var_to_partition (SA.map, exp);
3417
3418 if (part == NO_PARTITION)
3419 {
3420 /* If this is a reference to an incoming value of parameter
3421 that is never used in the code or where the incoming
3422 value is never used in the code, use PARM_DECL's
3423 DECL_RTL if set. */
3424 if (SSA_NAME_IS_DEFAULT_DEF (exp)
3425 && TREE_CODE (SSA_NAME_VAR (exp)) == PARM_DECL)
3426 {
3427 op0 = expand_debug_parm_decl (SSA_NAME_VAR (exp));
3428 if (op0)
3429 goto adjust_mode;
3430 op0 = expand_debug_expr (SSA_NAME_VAR (exp));
3431 if (op0)
3432 goto adjust_mode;
3433 }
3434 return NULL;
3435 }
3436
3437 gcc_assert (part >= 0 && (unsigned)part < SA.map->num_partitions);
3438
3439 op0 = copy_rtx (SA.partition_to_pseudo[part]);
3440 }
3441 goto adjust_mode;
3442 }
3443
3444 case ERROR_MARK:
3445 return NULL;
3446
3447 /* Vector stuff. For most of the codes we don't have rtl codes. */
3448 case REALIGN_LOAD_EXPR:
3449 case REDUC_MAX_EXPR:
3450 case REDUC_MIN_EXPR:
3451 case REDUC_PLUS_EXPR:
3452 case VEC_COND_EXPR:
3453 case VEC_LSHIFT_EXPR:
3454 case VEC_PACK_FIX_TRUNC_EXPR:
3455 case VEC_PACK_SAT_EXPR:
3456 case VEC_PACK_TRUNC_EXPR:
3457 case VEC_RSHIFT_EXPR:
3458 case VEC_UNPACK_FLOAT_HI_EXPR:
3459 case VEC_UNPACK_FLOAT_LO_EXPR:
3460 case VEC_UNPACK_HI_EXPR:
3461 case VEC_UNPACK_LO_EXPR:
3462 case VEC_WIDEN_MULT_HI_EXPR:
3463 case VEC_WIDEN_MULT_LO_EXPR:
3464 case VEC_WIDEN_LSHIFT_HI_EXPR:
3465 case VEC_WIDEN_LSHIFT_LO_EXPR:
3466 case VEC_PERM_EXPR:
3467 return NULL;
3468
3469 /* Misc codes. */
3470 case ADDR_SPACE_CONVERT_EXPR:
3471 case FIXED_CONVERT_EXPR:
3472 case OBJ_TYPE_REF:
3473 case WITH_SIZE_EXPR:
3474 return NULL;
3475
3476 case DOT_PROD_EXPR:
3477 if (SCALAR_INT_MODE_P (GET_MODE (op0))
3478 && SCALAR_INT_MODE_P (mode))
3479 {
3480 op0
3481 = simplify_gen_unary (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp,
3482 0)))
3483 ? ZERO_EXTEND : SIGN_EXTEND, mode, op0,
3484 inner_mode);
3485 op1
3486 = simplify_gen_unary (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp,
3487 1)))
3488 ? ZERO_EXTEND : SIGN_EXTEND, mode, op1,
3489 inner_mode);
3490 op0 = simplify_gen_binary (MULT, mode, op0, op1);
3491 return simplify_gen_binary (PLUS, mode, op0, op2);
3492 }
3493 return NULL;
3494
3495 case WIDEN_MULT_EXPR:
3496 case WIDEN_MULT_PLUS_EXPR:
3497 case WIDEN_MULT_MINUS_EXPR:
3498 if (SCALAR_INT_MODE_P (GET_MODE (op0))
3499 && SCALAR_INT_MODE_P (mode))
3500 {
3501 inner_mode = GET_MODE (op0);
3502 if (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0))))
3503 op0 = simplify_gen_unary (ZERO_EXTEND, mode, op0, inner_mode);
3504 else
3505 op0 = simplify_gen_unary (SIGN_EXTEND, mode, op0, inner_mode);
3506 if (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 1))))
3507 op1 = simplify_gen_unary (ZERO_EXTEND, mode, op1, inner_mode);
3508 else
3509 op1 = simplify_gen_unary (SIGN_EXTEND, mode, op1, inner_mode);
3510 op0 = simplify_gen_binary (MULT, mode, op0, op1);
3511 if (TREE_CODE (exp) == WIDEN_MULT_EXPR)
3512 return op0;
3513 else if (TREE_CODE (exp) == WIDEN_MULT_PLUS_EXPR)
3514 return simplify_gen_binary (PLUS, mode, op0, op2);
3515 else
3516 return simplify_gen_binary (MINUS, mode, op2, op0);
3517 }
3518 return NULL;
3519
3520 case WIDEN_SUM_EXPR:
3521 case WIDEN_LSHIFT_EXPR:
3522 if (SCALAR_INT_MODE_P (GET_MODE (op0))
3523 && SCALAR_INT_MODE_P (mode))
3524 {
3525 op0
3526 = simplify_gen_unary (TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp,
3527 0)))
3528 ? ZERO_EXTEND : SIGN_EXTEND, mode, op0,
3529 inner_mode);
3530 return simplify_gen_binary (TREE_CODE (exp) == WIDEN_LSHIFT_EXPR
3531 ? ASHIFT : PLUS, mode, op0, op1);
3532 }
3533 return NULL;
3534
3535 case FMA_EXPR:
3536 return simplify_gen_ternary (FMA, mode, inner_mode, op0, op1, op2);
3537
3538 default:
3539 flag_unsupported:
3540 #ifdef ENABLE_CHECKING
3541 debug_tree (exp);
3542 gcc_unreachable ();
3543 #else
3544 return NULL;
3545 #endif
3546 }
3547 }
3548
3549 /* Return an RTX equivalent to the source bind value of the tree expression
3550 EXP. */
3551
3552 static rtx
expand_debug_source_expr(tree exp)3553 expand_debug_source_expr (tree exp)
3554 {
3555 rtx op0 = NULL_RTX;
3556 enum machine_mode mode = VOIDmode, inner_mode;
3557
3558 switch (TREE_CODE (exp))
3559 {
3560 case PARM_DECL:
3561 {
3562 mode = DECL_MODE (exp);
3563 op0 = expand_debug_parm_decl (exp);
3564 if (op0)
3565 break;
3566 /* See if this isn't an argument that has been completely
3567 optimized out. */
3568 if (!DECL_RTL_SET_P (exp)
3569 && !DECL_INCOMING_RTL (exp)
3570 && DECL_ABSTRACT_ORIGIN (current_function_decl))
3571 {
3572 tree aexp = exp;
3573 if (DECL_ABSTRACT_ORIGIN (exp))
3574 aexp = DECL_ABSTRACT_ORIGIN (exp);
3575 if (DECL_CONTEXT (aexp)
3576 == DECL_ABSTRACT_ORIGIN (current_function_decl))
3577 {
3578 VEC(tree, gc) **debug_args;
3579 unsigned int ix;
3580 tree ddecl;
3581 #ifdef ENABLE_CHECKING
3582 tree parm;
3583 for (parm = DECL_ARGUMENTS (current_function_decl);
3584 parm; parm = DECL_CHAIN (parm))
3585 gcc_assert (parm != exp
3586 && DECL_ABSTRACT_ORIGIN (parm) != aexp);
3587 #endif
3588 debug_args = decl_debug_args_lookup (current_function_decl);
3589 if (debug_args != NULL)
3590 {
3591 for (ix = 0; VEC_iterate (tree, *debug_args, ix, ddecl);
3592 ix += 2)
3593 if (ddecl == aexp)
3594 return gen_rtx_DEBUG_PARAMETER_REF (mode, aexp);
3595 }
3596 }
3597 }
3598 break;
3599 }
3600 default:
3601 break;
3602 }
3603
3604 if (op0 == NULL_RTX)
3605 return NULL_RTX;
3606
3607 inner_mode = GET_MODE (op0);
3608 if (mode == inner_mode)
3609 return op0;
3610
3611 if (FLOAT_MODE_P (mode) && FLOAT_MODE_P (inner_mode))
3612 {
3613 if (GET_MODE_BITSIZE (mode) == GET_MODE_BITSIZE (inner_mode))
3614 op0 = simplify_gen_subreg (mode, op0, inner_mode, 0);
3615 else if (GET_MODE_BITSIZE (mode) < GET_MODE_BITSIZE (inner_mode))
3616 op0 = simplify_gen_unary (FLOAT_TRUNCATE, mode, op0, inner_mode);
3617 else
3618 op0 = simplify_gen_unary (FLOAT_EXTEND, mode, op0, inner_mode);
3619 }
3620 else if (FLOAT_MODE_P (mode))
3621 gcc_unreachable ();
3622 else if (FLOAT_MODE_P (inner_mode))
3623 {
3624 if (TYPE_UNSIGNED (TREE_TYPE (exp)))
3625 op0 = simplify_gen_unary (UNSIGNED_FIX, mode, op0, inner_mode);
3626 else
3627 op0 = simplify_gen_unary (FIX, mode, op0, inner_mode);
3628 }
3629 else if (CONSTANT_P (op0)
3630 || GET_MODE_BITSIZE (mode) <= GET_MODE_BITSIZE (inner_mode))
3631 op0 = simplify_gen_subreg (mode, op0, inner_mode,
3632 subreg_lowpart_offset (mode, inner_mode));
3633 else if (TYPE_UNSIGNED (TREE_TYPE (exp)))
3634 op0 = simplify_gen_unary (ZERO_EXTEND, mode, op0, inner_mode);
3635 else
3636 op0 = simplify_gen_unary (SIGN_EXTEND, mode, op0, inner_mode);
3637
3638 return op0;
3639 }
3640
3641 /* Ensure INSN_VAR_LOCATION_LOC (insn) doesn't have unbound complexity.
3642 Allow 4 levels of rtl nesting for most rtl codes, and if we see anything
3643 deeper than that, create DEBUG_EXPRs and emit DEBUG_INSNs before INSN. */
3644
3645 static void
avoid_complex_debug_insns(rtx insn,rtx * exp_p,int depth)3646 avoid_complex_debug_insns (rtx insn, rtx *exp_p, int depth)
3647 {
3648 rtx exp = *exp_p;
3649 const char *format_ptr;
3650 int i, j;
3651
3652 if (exp == NULL_RTX)
3653 return;
3654
3655 if ((OBJECT_P (exp) && !MEM_P (exp)) || GET_CODE (exp) == CLOBBER)
3656 return;
3657
3658 if (depth == 4)
3659 {
3660 /* Create DEBUG_EXPR (and DEBUG_EXPR_DECL). */
3661 rtx dval = make_debug_expr_from_rtl (exp);
3662
3663 /* Emit a debug bind insn before INSN. */
3664 rtx bind = gen_rtx_VAR_LOCATION (GET_MODE (exp),
3665 DEBUG_EXPR_TREE_DECL (dval), exp,
3666 VAR_INIT_STATUS_INITIALIZED);
3667
3668 emit_debug_insn_before (bind, insn);
3669 *exp_p = dval;
3670 return;
3671 }
3672
3673 format_ptr = GET_RTX_FORMAT (GET_CODE (exp));
3674 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (exp)); i++)
3675 switch (*format_ptr++)
3676 {
3677 case 'e':
3678 avoid_complex_debug_insns (insn, &XEXP (exp, i), depth + 1);
3679 break;
3680
3681 case 'E':
3682 case 'V':
3683 for (j = 0; j < XVECLEN (exp, i); j++)
3684 avoid_complex_debug_insns (insn, &XVECEXP (exp, i, j), depth + 1);
3685 break;
3686
3687 default:
3688 break;
3689 }
3690 }
3691
3692 /* Expand the _LOCs in debug insns. We run this after expanding all
3693 regular insns, so that any variables referenced in the function
3694 will have their DECL_RTLs set. */
3695
3696 static void
expand_debug_locations(void)3697 expand_debug_locations (void)
3698 {
3699 rtx insn;
3700 rtx last = get_last_insn ();
3701 int save_strict_alias = flag_strict_aliasing;
3702
3703 /* New alias sets while setting up memory attributes cause
3704 -fcompare-debug failures, even though it doesn't bring about any
3705 codegen changes. */
3706 flag_strict_aliasing = 0;
3707
3708 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3709 if (DEBUG_INSN_P (insn))
3710 {
3711 tree value = (tree)INSN_VAR_LOCATION_LOC (insn);
3712 rtx val, prev_insn, insn2;
3713 enum machine_mode mode;
3714
3715 if (value == NULL_TREE)
3716 val = NULL_RTX;
3717 else
3718 {
3719 if (INSN_VAR_LOCATION_STATUS (insn)
3720 == VAR_INIT_STATUS_UNINITIALIZED)
3721 val = expand_debug_source_expr (value);
3722 else
3723 val = expand_debug_expr (value);
3724 gcc_assert (last == get_last_insn ());
3725 }
3726
3727 if (!val)
3728 val = gen_rtx_UNKNOWN_VAR_LOC ();
3729 else
3730 {
3731 mode = GET_MODE (INSN_VAR_LOCATION (insn));
3732
3733 gcc_assert (mode == GET_MODE (val)
3734 || (GET_MODE (val) == VOIDmode
3735 && (CONST_INT_P (val)
3736 || GET_CODE (val) == CONST_FIXED
3737 || GET_CODE (val) == CONST_DOUBLE
3738 || GET_CODE (val) == LABEL_REF)));
3739 }
3740
3741 INSN_VAR_LOCATION_LOC (insn) = val;
3742 prev_insn = PREV_INSN (insn);
3743 for (insn2 = insn; insn2 != prev_insn; insn2 = PREV_INSN (insn2))
3744 avoid_complex_debug_insns (insn2, &INSN_VAR_LOCATION_LOC (insn2), 0);
3745 }
3746
3747 flag_strict_aliasing = save_strict_alias;
3748 }
3749
3750 /* Expand basic block BB from GIMPLE trees to RTL. */
3751
3752 static basic_block
expand_gimple_basic_block(basic_block bb)3753 expand_gimple_basic_block (basic_block bb)
3754 {
3755 gimple_stmt_iterator gsi;
3756 gimple_seq stmts;
3757 gimple stmt = NULL;
3758 rtx note, last;
3759 edge e;
3760 edge_iterator ei;
3761 void **elt;
3762
3763 if (dump_file)
3764 fprintf (dump_file, "\n;; Generating RTL for gimple basic block %d\n",
3765 bb->index);
3766
3767 /* Note that since we are now transitioning from GIMPLE to RTL, we
3768 cannot use the gsi_*_bb() routines because they expect the basic
3769 block to be in GIMPLE, instead of RTL. Therefore, we need to
3770 access the BB sequence directly. */
3771 stmts = bb_seq (bb);
3772 bb->il.gimple = NULL;
3773 rtl_profile_for_bb (bb);
3774 init_rtl_bb_info (bb);
3775 bb->flags |= BB_RTL;
3776
3777 /* Remove the RETURN_EXPR if we may fall though to the exit
3778 instead. */
3779 gsi = gsi_last (stmts);
3780 if (!gsi_end_p (gsi)
3781 && gimple_code (gsi_stmt (gsi)) == GIMPLE_RETURN)
3782 {
3783 gimple ret_stmt = gsi_stmt (gsi);
3784
3785 gcc_assert (single_succ_p (bb));
3786 gcc_assert (single_succ (bb) == EXIT_BLOCK_PTR);
3787
3788 if (bb->next_bb == EXIT_BLOCK_PTR
3789 && !gimple_return_retval (ret_stmt))
3790 {
3791 gsi_remove (&gsi, false);
3792 single_succ_edge (bb)->flags |= EDGE_FALLTHRU;
3793 }
3794 }
3795
3796 gsi = gsi_start (stmts);
3797 if (!gsi_end_p (gsi))
3798 {
3799 stmt = gsi_stmt (gsi);
3800 if (gimple_code (stmt) != GIMPLE_LABEL)
3801 stmt = NULL;
3802 }
3803
3804 elt = pointer_map_contains (lab_rtx_for_bb, bb);
3805
3806 if (stmt || elt)
3807 {
3808 last = get_last_insn ();
3809
3810 if (stmt)
3811 {
3812 expand_gimple_stmt (stmt);
3813 gsi_next (&gsi);
3814 }
3815
3816 if (elt)
3817 emit_label ((rtx) *elt);
3818
3819 /* Java emits line number notes in the top of labels.
3820 ??? Make this go away once line number notes are obsoleted. */
3821 BB_HEAD (bb) = NEXT_INSN (last);
3822 if (NOTE_P (BB_HEAD (bb)))
3823 BB_HEAD (bb) = NEXT_INSN (BB_HEAD (bb));
3824 note = emit_note_after (NOTE_INSN_BASIC_BLOCK, BB_HEAD (bb));
3825
3826 maybe_dump_rtl_for_gimple_stmt (stmt, last);
3827 }
3828 else
3829 note = BB_HEAD (bb) = emit_note (NOTE_INSN_BASIC_BLOCK);
3830
3831 NOTE_BASIC_BLOCK (note) = bb;
3832
3833 for (; !gsi_end_p (gsi); gsi_next (&gsi))
3834 {
3835 basic_block new_bb;
3836
3837 stmt = gsi_stmt (gsi);
3838
3839 /* If this statement is a non-debug one, and we generate debug
3840 insns, then this one might be the last real use of a TERed
3841 SSA_NAME, but where there are still some debug uses further
3842 down. Expanding the current SSA name in such further debug
3843 uses by their RHS might lead to wrong debug info, as coalescing
3844 might make the operands of such RHS be placed into the same
3845 pseudo as something else. Like so:
3846 a_1 = a_0 + 1; // Assume a_1 is TERed and a_0 is dead
3847 use(a_1);
3848 a_2 = ...
3849 #DEBUG ... => a_1
3850 As a_0 and a_2 don't overlap in lifetime, assume they are coalesced.
3851 If we now would expand a_1 by it's RHS (a_0 + 1) in the debug use,
3852 the write to a_2 would actually have clobbered the place which
3853 formerly held a_0.
3854
3855 So, instead of that, we recognize the situation, and generate
3856 debug temporaries at the last real use of TERed SSA names:
3857 a_1 = a_0 + 1;
3858 #DEBUG #D1 => a_1
3859 use(a_1);
3860 a_2 = ...
3861 #DEBUG ... => #D1
3862 */
3863 if (MAY_HAVE_DEBUG_INSNS
3864 && SA.values
3865 && !is_gimple_debug (stmt))
3866 {
3867 ssa_op_iter iter;
3868 tree op;
3869 gimple def;
3870
3871 location_t sloc = get_curr_insn_source_location ();
3872 tree sblock = get_curr_insn_block ();
3873
3874 /* Look for SSA names that have their last use here (TERed
3875 names always have only one real use). */
3876 FOR_EACH_SSA_TREE_OPERAND (op, stmt, iter, SSA_OP_USE)
3877 if ((def = get_gimple_for_ssa_name (op)))
3878 {
3879 imm_use_iterator imm_iter;
3880 use_operand_p use_p;
3881 bool have_debug_uses = false;
3882
3883 FOR_EACH_IMM_USE_FAST (use_p, imm_iter, op)
3884 {
3885 if (gimple_debug_bind_p (USE_STMT (use_p)))
3886 {
3887 have_debug_uses = true;
3888 break;
3889 }
3890 }
3891
3892 if (have_debug_uses)
3893 {
3894 /* OP is a TERed SSA name, with DEF it's defining
3895 statement, and where OP is used in further debug
3896 instructions. Generate a debug temporary, and
3897 replace all uses of OP in debug insns with that
3898 temporary. */
3899 gimple debugstmt;
3900 tree value = gimple_assign_rhs_to_tree (def);
3901 tree vexpr = make_node (DEBUG_EXPR_DECL);
3902 rtx val;
3903 enum machine_mode mode;
3904
3905 set_curr_insn_source_location (gimple_location (def));
3906 set_curr_insn_block (gimple_block (def));
3907
3908 DECL_ARTIFICIAL (vexpr) = 1;
3909 TREE_TYPE (vexpr) = TREE_TYPE (value);
3910 if (DECL_P (value))
3911 mode = DECL_MODE (value);
3912 else
3913 mode = TYPE_MODE (TREE_TYPE (value));
3914 DECL_MODE (vexpr) = mode;
3915
3916 val = gen_rtx_VAR_LOCATION
3917 (mode, vexpr, (rtx)value, VAR_INIT_STATUS_INITIALIZED);
3918
3919 emit_debug_insn (val);
3920
3921 FOR_EACH_IMM_USE_STMT (debugstmt, imm_iter, op)
3922 {
3923 if (!gimple_debug_bind_p (debugstmt))
3924 continue;
3925
3926 FOR_EACH_IMM_USE_ON_STMT (use_p, imm_iter)
3927 SET_USE (use_p, vexpr);
3928
3929 update_stmt (debugstmt);
3930 }
3931 }
3932 }
3933 set_curr_insn_source_location (sloc);
3934 set_curr_insn_block (sblock);
3935 }
3936
3937 currently_expanding_gimple_stmt = stmt;
3938
3939 /* Expand this statement, then evaluate the resulting RTL and
3940 fixup the CFG accordingly. */
3941 if (gimple_code (stmt) == GIMPLE_COND)
3942 {
3943 new_bb = expand_gimple_cond (bb, stmt);
3944 if (new_bb)
3945 return new_bb;
3946 }
3947 else if (gimple_debug_bind_p (stmt))
3948 {
3949 location_t sloc = get_curr_insn_source_location ();
3950 tree sblock = get_curr_insn_block ();
3951 gimple_stmt_iterator nsi = gsi;
3952
3953 for (;;)
3954 {
3955 tree var = gimple_debug_bind_get_var (stmt);
3956 tree value;
3957 rtx val;
3958 enum machine_mode mode;
3959
3960 if (TREE_CODE (var) != DEBUG_EXPR_DECL
3961 && TREE_CODE (var) != LABEL_DECL
3962 && !target_for_debug_bind (var))
3963 goto delink_debug_stmt;
3964
3965 if (gimple_debug_bind_has_value_p (stmt))
3966 value = gimple_debug_bind_get_value (stmt);
3967 else
3968 value = NULL_TREE;
3969
3970 last = get_last_insn ();
3971
3972 set_curr_insn_source_location (gimple_location (stmt));
3973 set_curr_insn_block (gimple_block (stmt));
3974
3975 if (DECL_P (var))
3976 mode = DECL_MODE (var);
3977 else
3978 mode = TYPE_MODE (TREE_TYPE (var));
3979
3980 val = gen_rtx_VAR_LOCATION
3981 (mode, var, (rtx)value, VAR_INIT_STATUS_INITIALIZED);
3982
3983 emit_debug_insn (val);
3984
3985 if (dump_file && (dump_flags & TDF_DETAILS))
3986 {
3987 /* We can't dump the insn with a TREE where an RTX
3988 is expected. */
3989 PAT_VAR_LOCATION_LOC (val) = const0_rtx;
3990 maybe_dump_rtl_for_gimple_stmt (stmt, last);
3991 PAT_VAR_LOCATION_LOC (val) = (rtx)value;
3992 }
3993
3994 delink_debug_stmt:
3995 /* In order not to generate too many debug temporaries,
3996 we delink all uses of debug statements we already expanded.
3997 Therefore debug statements between definition and real
3998 use of TERed SSA names will continue to use the SSA name,
3999 and not be replaced with debug temps. */
4000 delink_stmt_imm_use (stmt);
4001
4002 gsi = nsi;
4003 gsi_next (&nsi);
4004 if (gsi_end_p (nsi))
4005 break;
4006 stmt = gsi_stmt (nsi);
4007 if (!gimple_debug_bind_p (stmt))
4008 break;
4009 }
4010
4011 set_curr_insn_source_location (sloc);
4012 set_curr_insn_block (sblock);
4013 }
4014 else if (gimple_debug_source_bind_p (stmt))
4015 {
4016 location_t sloc = get_curr_insn_source_location ();
4017 tree sblock = get_curr_insn_block ();
4018 tree var = gimple_debug_source_bind_get_var (stmt);
4019 tree value = gimple_debug_source_bind_get_value (stmt);
4020 rtx val;
4021 enum machine_mode mode;
4022
4023 last = get_last_insn ();
4024
4025 set_curr_insn_source_location (gimple_location (stmt));
4026 set_curr_insn_block (gimple_block (stmt));
4027
4028 mode = DECL_MODE (var);
4029
4030 val = gen_rtx_VAR_LOCATION (mode, var, (rtx)value,
4031 VAR_INIT_STATUS_UNINITIALIZED);
4032
4033 emit_debug_insn (val);
4034
4035 if (dump_file && (dump_flags & TDF_DETAILS))
4036 {
4037 /* We can't dump the insn with a TREE where an RTX
4038 is expected. */
4039 PAT_VAR_LOCATION_LOC (val) = const0_rtx;
4040 maybe_dump_rtl_for_gimple_stmt (stmt, last);
4041 PAT_VAR_LOCATION_LOC (val) = (rtx)value;
4042 }
4043
4044 set_curr_insn_source_location (sloc);
4045 set_curr_insn_block (sblock);
4046 }
4047 else
4048 {
4049 if (is_gimple_call (stmt) && gimple_call_tail_p (stmt))
4050 {
4051 bool can_fallthru;
4052 new_bb = expand_gimple_tailcall (bb, stmt, &can_fallthru);
4053 if (new_bb)
4054 {
4055 if (can_fallthru)
4056 bb = new_bb;
4057 else
4058 return new_bb;
4059 }
4060 }
4061 else
4062 {
4063 def_operand_p def_p;
4064 def_p = SINGLE_SSA_DEF_OPERAND (stmt, SSA_OP_DEF);
4065
4066 if (def_p != NULL)
4067 {
4068 /* Ignore this stmt if it is in the list of
4069 replaceable expressions. */
4070 if (SA.values
4071 && bitmap_bit_p (SA.values,
4072 SSA_NAME_VERSION (DEF_FROM_PTR (def_p))))
4073 continue;
4074 }
4075 last = expand_gimple_stmt (stmt);
4076 maybe_dump_rtl_for_gimple_stmt (stmt, last);
4077 }
4078 }
4079 }
4080
4081 currently_expanding_gimple_stmt = NULL;
4082
4083 /* Expand implicit goto and convert goto_locus. */
4084 FOR_EACH_EDGE (e, ei, bb->succs)
4085 {
4086 if (e->goto_locus && e->goto_block)
4087 {
4088 set_curr_insn_source_location (e->goto_locus);
4089 set_curr_insn_block (e->goto_block);
4090 e->goto_locus = curr_insn_locator ();
4091 }
4092 e->goto_block = NULL;
4093 if ((e->flags & EDGE_FALLTHRU) && e->dest != bb->next_bb)
4094 {
4095 emit_jump (label_rtx_for_bb (e->dest));
4096 e->flags &= ~EDGE_FALLTHRU;
4097 }
4098 }
4099
4100 /* Expanded RTL can create a jump in the last instruction of block.
4101 This later might be assumed to be a jump to successor and break edge insertion.
4102 We need to insert dummy move to prevent this. PR41440. */
4103 if (single_succ_p (bb)
4104 && (single_succ_edge (bb)->flags & EDGE_FALLTHRU)
4105 && (last = get_last_insn ())
4106 && JUMP_P (last))
4107 {
4108 rtx dummy = gen_reg_rtx (SImode);
4109 emit_insn_after_noloc (gen_move_insn (dummy, dummy), last, NULL);
4110 }
4111
4112 do_pending_stack_adjust ();
4113
4114 /* Find the block tail. The last insn in the block is the insn
4115 before a barrier and/or table jump insn. */
4116 last = get_last_insn ();
4117 if (BARRIER_P (last))
4118 last = PREV_INSN (last);
4119 if (JUMP_TABLE_DATA_P (last))
4120 last = PREV_INSN (PREV_INSN (last));
4121 BB_END (bb) = last;
4122
4123 update_bb_for_insn (bb);
4124
4125 return bb;
4126 }
4127
4128
4129 /* Create a basic block for initialization code. */
4130
4131 static basic_block
construct_init_block(void)4132 construct_init_block (void)
4133 {
4134 basic_block init_block, first_block;
4135 edge e = NULL;
4136 int flags;
4137
4138 /* Multiple entry points not supported yet. */
4139 gcc_assert (EDGE_COUNT (ENTRY_BLOCK_PTR->succs) == 1);
4140 init_rtl_bb_info (ENTRY_BLOCK_PTR);
4141 init_rtl_bb_info (EXIT_BLOCK_PTR);
4142 ENTRY_BLOCK_PTR->flags |= BB_RTL;
4143 EXIT_BLOCK_PTR->flags |= BB_RTL;
4144
4145 e = EDGE_SUCC (ENTRY_BLOCK_PTR, 0);
4146
4147 /* When entry edge points to first basic block, we don't need jump,
4148 otherwise we have to jump into proper target. */
4149 if (e && e->dest != ENTRY_BLOCK_PTR->next_bb)
4150 {
4151 tree label = gimple_block_label (e->dest);
4152
4153 emit_jump (label_rtx (label));
4154 flags = 0;
4155 }
4156 else
4157 flags = EDGE_FALLTHRU;
4158
4159 init_block = create_basic_block (NEXT_INSN (get_insns ()),
4160 get_last_insn (),
4161 ENTRY_BLOCK_PTR);
4162 init_block->frequency = ENTRY_BLOCK_PTR->frequency;
4163 init_block->count = ENTRY_BLOCK_PTR->count;
4164 if (e)
4165 {
4166 first_block = e->dest;
4167 redirect_edge_succ (e, init_block);
4168 e = make_edge (init_block, first_block, flags);
4169 }
4170 else
4171 e = make_edge (init_block, EXIT_BLOCK_PTR, EDGE_FALLTHRU);
4172 e->probability = REG_BR_PROB_BASE;
4173 e->count = ENTRY_BLOCK_PTR->count;
4174
4175 update_bb_for_insn (init_block);
4176 return init_block;
4177 }
4178
4179 /* For each lexical block, set BLOCK_NUMBER to the depth at which it is
4180 found in the block tree. */
4181
4182 static void
set_block_levels(tree block,int level)4183 set_block_levels (tree block, int level)
4184 {
4185 while (block)
4186 {
4187 BLOCK_NUMBER (block) = level;
4188 set_block_levels (BLOCK_SUBBLOCKS (block), level + 1);
4189 block = BLOCK_CHAIN (block);
4190 }
4191 }
4192
4193 /* Create a block containing landing pads and similar stuff. */
4194
4195 static void
construct_exit_block(void)4196 construct_exit_block (void)
4197 {
4198 rtx head = get_last_insn ();
4199 rtx end;
4200 basic_block exit_block;
4201 edge e, e2;
4202 unsigned ix;
4203 edge_iterator ei;
4204 rtx orig_end = BB_END (EXIT_BLOCK_PTR->prev_bb);
4205
4206 rtl_profile_for_bb (EXIT_BLOCK_PTR);
4207
4208 /* Make sure the locus is set to the end of the function, so that
4209 epilogue line numbers and warnings are set properly. */
4210 if (cfun->function_end_locus != UNKNOWN_LOCATION)
4211 input_location = cfun->function_end_locus;
4212
4213 /* The following insns belong to the top scope. */
4214 set_curr_insn_block (DECL_INITIAL (current_function_decl));
4215
4216 /* Generate rtl for function exit. */
4217 expand_function_end ();
4218
4219 end = get_last_insn ();
4220 if (head == end)
4221 return;
4222 /* While emitting the function end we could move end of the last basic block.
4223 */
4224 BB_END (EXIT_BLOCK_PTR->prev_bb) = orig_end;
4225 while (NEXT_INSN (head) && NOTE_P (NEXT_INSN (head)))
4226 head = NEXT_INSN (head);
4227 exit_block = create_basic_block (NEXT_INSN (head), end,
4228 EXIT_BLOCK_PTR->prev_bb);
4229 exit_block->frequency = EXIT_BLOCK_PTR->frequency;
4230 exit_block->count = EXIT_BLOCK_PTR->count;
4231
4232 ix = 0;
4233 while (ix < EDGE_COUNT (EXIT_BLOCK_PTR->preds))
4234 {
4235 e = EDGE_PRED (EXIT_BLOCK_PTR, ix);
4236 if (!(e->flags & EDGE_ABNORMAL))
4237 redirect_edge_succ (e, exit_block);
4238 else
4239 ix++;
4240 }
4241
4242 e = make_edge (exit_block, EXIT_BLOCK_PTR, EDGE_FALLTHRU);
4243 e->probability = REG_BR_PROB_BASE;
4244 e->count = EXIT_BLOCK_PTR->count;
4245 FOR_EACH_EDGE (e2, ei, EXIT_BLOCK_PTR->preds)
4246 if (e2 != e)
4247 {
4248 e->count -= e2->count;
4249 exit_block->count -= e2->count;
4250 exit_block->frequency -= EDGE_FREQUENCY (e2);
4251 }
4252 if (e->count < 0)
4253 e->count = 0;
4254 if (exit_block->count < 0)
4255 exit_block->count = 0;
4256 if (exit_block->frequency < 0)
4257 exit_block->frequency = 0;
4258 update_bb_for_insn (exit_block);
4259 }
4260
4261 /* Helper function for discover_nonconstant_array_refs.
4262 Look for ARRAY_REF nodes with non-constant indexes and mark them
4263 addressable. */
4264
4265 static tree
discover_nonconstant_array_refs_r(tree * tp,int * walk_subtrees,void * data ATTRIBUTE_UNUSED)4266 discover_nonconstant_array_refs_r (tree * tp, int *walk_subtrees,
4267 void *data ATTRIBUTE_UNUSED)
4268 {
4269 tree t = *tp;
4270
4271 if (IS_TYPE_OR_DECL_P (t))
4272 *walk_subtrees = 0;
4273 else if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4274 {
4275 while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4276 && is_gimple_min_invariant (TREE_OPERAND (t, 1))
4277 && (!TREE_OPERAND (t, 2)
4278 || is_gimple_min_invariant (TREE_OPERAND (t, 2))))
4279 || (TREE_CODE (t) == COMPONENT_REF
4280 && (!TREE_OPERAND (t,2)
4281 || is_gimple_min_invariant (TREE_OPERAND (t, 2))))
4282 || TREE_CODE (t) == BIT_FIELD_REF
4283 || TREE_CODE (t) == REALPART_EXPR
4284 || TREE_CODE (t) == IMAGPART_EXPR
4285 || TREE_CODE (t) == VIEW_CONVERT_EXPR
4286 || CONVERT_EXPR_P (t))
4287 t = TREE_OPERAND (t, 0);
4288
4289 if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF)
4290 {
4291 t = get_base_address (t);
4292 if (t && DECL_P (t)
4293 && DECL_MODE (t) != BLKmode)
4294 TREE_ADDRESSABLE (t) = 1;
4295 }
4296
4297 *walk_subtrees = 0;
4298 }
4299
4300 return NULL_TREE;
4301 }
4302
4303 /* RTL expansion is not able to compile array references with variable
4304 offsets for arrays stored in single register. Discover such
4305 expressions and mark variables as addressable to avoid this
4306 scenario. */
4307
4308 static void
discover_nonconstant_array_refs(void)4309 discover_nonconstant_array_refs (void)
4310 {
4311 basic_block bb;
4312 gimple_stmt_iterator gsi;
4313
4314 FOR_EACH_BB (bb)
4315 for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
4316 {
4317 gimple stmt = gsi_stmt (gsi);
4318 if (!is_gimple_debug (stmt))
4319 walk_gimple_op (stmt, discover_nonconstant_array_refs_r, NULL);
4320 }
4321 }
4322
4323 /* This function sets crtl->args.internal_arg_pointer to a virtual
4324 register if DRAP is needed. Local register allocator will replace
4325 virtual_incoming_args_rtx with the virtual register. */
4326
4327 static void
expand_stack_alignment(void)4328 expand_stack_alignment (void)
4329 {
4330 rtx drap_rtx;
4331 unsigned int preferred_stack_boundary;
4332
4333 if (! SUPPORTS_STACK_ALIGNMENT)
4334 return;
4335
4336 if (cfun->calls_alloca
4337 || cfun->has_nonlocal_label
4338 || crtl->has_nonlocal_goto)
4339 crtl->need_drap = true;
4340
4341 /* Call update_stack_boundary here again to update incoming stack
4342 boundary. It may set incoming stack alignment to a different
4343 value after RTL expansion. TARGET_FUNCTION_OK_FOR_SIBCALL may
4344 use the minimum incoming stack alignment to check if it is OK
4345 to perform sibcall optimization since sibcall optimization will
4346 only align the outgoing stack to incoming stack boundary. */
4347 if (targetm.calls.update_stack_boundary)
4348 targetm.calls.update_stack_boundary ();
4349
4350 /* The incoming stack frame has to be aligned at least at
4351 parm_stack_boundary. */
4352 gcc_assert (crtl->parm_stack_boundary <= INCOMING_STACK_BOUNDARY);
4353
4354 /* Update crtl->stack_alignment_estimated and use it later to align
4355 stack. We check PREFERRED_STACK_BOUNDARY if there may be non-call
4356 exceptions since callgraph doesn't collect incoming stack alignment
4357 in this case. */
4358 if (cfun->can_throw_non_call_exceptions
4359 && PREFERRED_STACK_BOUNDARY > crtl->preferred_stack_boundary)
4360 preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
4361 else
4362 preferred_stack_boundary = crtl->preferred_stack_boundary;
4363 if (preferred_stack_boundary > crtl->stack_alignment_estimated)
4364 crtl->stack_alignment_estimated = preferred_stack_boundary;
4365 if (preferred_stack_boundary > crtl->stack_alignment_needed)
4366 crtl->stack_alignment_needed = preferred_stack_boundary;
4367
4368 gcc_assert (crtl->stack_alignment_needed
4369 <= crtl->stack_alignment_estimated);
4370
4371 crtl->stack_realign_needed
4372 = INCOMING_STACK_BOUNDARY < crtl->stack_alignment_estimated;
4373 crtl->stack_realign_tried = crtl->stack_realign_needed;
4374
4375 crtl->stack_realign_processed = true;
4376
4377 /* Target has to redefine TARGET_GET_DRAP_RTX to support stack
4378 alignment. */
4379 gcc_assert (targetm.calls.get_drap_rtx != NULL);
4380 drap_rtx = targetm.calls.get_drap_rtx ();
4381
4382 /* stack_realign_drap and drap_rtx must match. */
4383 gcc_assert ((stack_realign_drap != 0) == (drap_rtx != NULL));
4384
4385 /* Do nothing if NULL is returned, which means DRAP is not needed. */
4386 if (NULL != drap_rtx)
4387 {
4388 crtl->args.internal_arg_pointer = drap_rtx;
4389
4390 /* Call fixup_tail_calls to clean up REG_EQUIV note if DRAP is
4391 needed. */
4392 fixup_tail_calls ();
4393 }
4394 }
4395
4396 /* Translate the intermediate representation contained in the CFG
4397 from GIMPLE trees to RTL.
4398
4399 We do conversion per basic block and preserve/update the tree CFG.
4400 This implies we have to do some magic as the CFG can simultaneously
4401 consist of basic blocks containing RTL and GIMPLE trees. This can
4402 confuse the CFG hooks, so be careful to not manipulate CFG during
4403 the expansion. */
4404
4405 static unsigned int
gimple_expand_cfg(void)4406 gimple_expand_cfg (void)
4407 {
4408 basic_block bb, init_block;
4409 sbitmap blocks;
4410 edge_iterator ei;
4411 edge e;
4412 rtx var_seq;
4413 unsigned i;
4414
4415 timevar_push (TV_OUT_OF_SSA);
4416 rewrite_out_of_ssa (&SA);
4417 timevar_pop (TV_OUT_OF_SSA);
4418 SA.partition_to_pseudo = (rtx *)xcalloc (SA.map->num_partitions,
4419 sizeof (rtx));
4420
4421 /* Some backends want to know that we are expanding to RTL. */
4422 currently_expanding_to_rtl = 1;
4423
4424 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
4425
4426 insn_locators_alloc ();
4427 if (!DECL_IS_BUILTIN (current_function_decl))
4428 {
4429 /* Eventually, all FEs should explicitly set function_start_locus. */
4430 if (cfun->function_start_locus == UNKNOWN_LOCATION)
4431 set_curr_insn_source_location
4432 (DECL_SOURCE_LOCATION (current_function_decl));
4433 else
4434 set_curr_insn_source_location (cfun->function_start_locus);
4435 }
4436 else
4437 set_curr_insn_source_location (UNKNOWN_LOCATION);
4438 set_curr_insn_block (DECL_INITIAL (current_function_decl));
4439 prologue_locator = curr_insn_locator ();
4440
4441 #ifdef INSN_SCHEDULING
4442 init_sched_attrs ();
4443 #endif
4444
4445 /* Make sure first insn is a note even if we don't want linenums.
4446 This makes sure the first insn will never be deleted.
4447 Also, final expects a note to appear there. */
4448 emit_note (NOTE_INSN_DELETED);
4449
4450 /* Mark arrays indexed with non-constant indices with TREE_ADDRESSABLE. */
4451 discover_nonconstant_array_refs ();
4452
4453 targetm.expand_to_rtl_hook ();
4454 crtl->stack_alignment_needed = STACK_BOUNDARY;
4455 crtl->max_used_stack_slot_alignment = STACK_BOUNDARY;
4456 crtl->stack_alignment_estimated = 0;
4457 crtl->preferred_stack_boundary = STACK_BOUNDARY;
4458 cfun->cfg->max_jumptable_ents = 0;
4459
4460 /* Resovle the function section. Some targets, like ARM EABI rely on knowledge
4461 of the function section at exapnsion time to predict distance of calls. */
4462 resolve_unique_section (current_function_decl, 0, flag_function_sections);
4463
4464 /* Expand the variables recorded during gimple lowering. */
4465 timevar_push (TV_VAR_EXPAND);
4466 start_sequence ();
4467
4468 expand_used_vars ();
4469
4470 var_seq = get_insns ();
4471 end_sequence ();
4472 timevar_pop (TV_VAR_EXPAND);
4473
4474 /* Honor stack protection warnings. */
4475 if (warn_stack_protect)
4476 {
4477 if (cfun->calls_alloca)
4478 warning (OPT_Wstack_protector,
4479 "stack protector not protecting local variables: "
4480 "variable length buffer");
4481 if (has_short_buffer && !crtl->stack_protect_guard)
4482 warning (OPT_Wstack_protector,
4483 "stack protector not protecting function: "
4484 "all local arrays are less than %d bytes long",
4485 (int) PARAM_VALUE (PARAM_SSP_BUFFER_SIZE));
4486 }
4487
4488 /* Set up parameters and prepare for return, for the function. */
4489 expand_function_start (current_function_decl);
4490
4491 /* If we emitted any instructions for setting up the variables,
4492 emit them before the FUNCTION_START note. */
4493 if (var_seq)
4494 {
4495 emit_insn_before (var_seq, parm_birth_insn);
4496
4497 /* In expand_function_end we'll insert the alloca save/restore
4498 before parm_birth_insn. We've just insertted an alloca call.
4499 Adjust the pointer to match. */
4500 parm_birth_insn = var_seq;
4501 }
4502
4503 /* Now that we also have the parameter RTXs, copy them over to our
4504 partitions. */
4505 for (i = 0; i < SA.map->num_partitions; i++)
4506 {
4507 tree var = SSA_NAME_VAR (partition_to_var (SA.map, i));
4508
4509 if (TREE_CODE (var) != VAR_DECL
4510 && !SA.partition_to_pseudo[i])
4511 SA.partition_to_pseudo[i] = DECL_RTL_IF_SET (var);
4512 gcc_assert (SA.partition_to_pseudo[i]);
4513
4514 /* If this decl was marked as living in multiple places, reset
4515 this now to NULL. */
4516 if (DECL_RTL_IF_SET (var) == pc_rtx)
4517 SET_DECL_RTL (var, NULL);
4518
4519 /* Some RTL parts really want to look at DECL_RTL(x) when x
4520 was a decl marked in REG_ATTR or MEM_ATTR. We could use
4521 SET_DECL_RTL here making this available, but that would mean
4522 to select one of the potentially many RTLs for one DECL. Instead
4523 of doing that we simply reset the MEM_EXPR of the RTL in question,
4524 then nobody can get at it and hence nobody can call DECL_RTL on it. */
4525 if (!DECL_RTL_SET_P (var))
4526 {
4527 if (MEM_P (SA.partition_to_pseudo[i]))
4528 set_mem_expr (SA.partition_to_pseudo[i], NULL);
4529 }
4530 }
4531
4532 /* If we have a class containing differently aligned pointers
4533 we need to merge those into the corresponding RTL pointer
4534 alignment. */
4535 for (i = 1; i < num_ssa_names; i++)
4536 {
4537 tree name = ssa_name (i);
4538 int part;
4539 rtx r;
4540
4541 if (!name
4542 || !POINTER_TYPE_P (TREE_TYPE (name))
4543 /* We might have generated new SSA names in
4544 update_alias_info_with_stack_vars. They will have a NULL
4545 defining statements, and won't be part of the partitioning,
4546 so ignore those. */
4547 || !SSA_NAME_DEF_STMT (name))
4548 continue;
4549 part = var_to_partition (SA.map, name);
4550 if (part == NO_PARTITION)
4551 continue;
4552 r = SA.partition_to_pseudo[part];
4553 if (REG_P (r))
4554 mark_reg_pointer (r, get_pointer_alignment (name));
4555 }
4556
4557 /* If this function is `main', emit a call to `__main'
4558 to run global initializers, etc. */
4559 if (DECL_NAME (current_function_decl)
4560 && MAIN_NAME_P (DECL_NAME (current_function_decl))
4561 && DECL_FILE_SCOPE_P (current_function_decl))
4562 expand_main_function ();
4563
4564 /* Initialize the stack_protect_guard field. This must happen after the
4565 call to __main (if any) so that the external decl is initialized. */
4566 if (crtl->stack_protect_guard)
4567 stack_protect_prologue ();
4568
4569 expand_phi_nodes (&SA);
4570
4571 /* Register rtl specific functions for cfg. */
4572 rtl_register_cfg_hooks ();
4573
4574 init_block = construct_init_block ();
4575
4576 /* Clear EDGE_EXECUTABLE on the entry edge(s). It is cleaned from the
4577 remaining edges later. */
4578 FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs)
4579 e->flags &= ~EDGE_EXECUTABLE;
4580
4581 lab_rtx_for_bb = pointer_map_create ();
4582 FOR_BB_BETWEEN (bb, init_block->next_bb, EXIT_BLOCK_PTR, next_bb)
4583 bb = expand_gimple_basic_block (bb);
4584
4585 if (MAY_HAVE_DEBUG_INSNS)
4586 expand_debug_locations ();
4587
4588 execute_free_datastructures ();
4589 timevar_push (TV_OUT_OF_SSA);
4590 finish_out_of_ssa (&SA);
4591 timevar_pop (TV_OUT_OF_SSA);
4592
4593 timevar_push (TV_POST_EXPAND);
4594 /* We are no longer in SSA form. */
4595 cfun->gimple_df->in_ssa_p = false;
4596
4597 /* Expansion is used by optimization passes too, set maybe_hot_insn_p
4598 conservatively to true until they are all profile aware. */
4599 pointer_map_destroy (lab_rtx_for_bb);
4600 free_histograms ();
4601
4602 construct_exit_block ();
4603 set_curr_insn_block (DECL_INITIAL (current_function_decl));
4604 insn_locators_finalize ();
4605
4606 /* Zap the tree EH table. */
4607 set_eh_throw_stmt_table (cfun, NULL);
4608
4609 /* We need JUMP_LABEL be set in order to redirect jumps, and hence
4610 split edges which edge insertions might do. */
4611 rebuild_jump_labels (get_insns ());
4612
4613 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb)
4614 {
4615 edge e;
4616 edge_iterator ei;
4617 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
4618 {
4619 if (e->insns.r)
4620 {
4621 rebuild_jump_labels_chain (e->insns.r);
4622 /* Avoid putting insns before parm_birth_insn. */
4623 if (e->src == ENTRY_BLOCK_PTR
4624 && single_succ_p (ENTRY_BLOCK_PTR)
4625 && parm_birth_insn)
4626 {
4627 rtx insns = e->insns.r;
4628 e->insns.r = NULL_RTX;
4629 emit_insn_after_noloc (insns, parm_birth_insn, e->dest);
4630 }
4631 else
4632 commit_one_edge_insertion (e);
4633 }
4634 else
4635 ei_next (&ei);
4636 }
4637 }
4638
4639 /* We're done expanding trees to RTL. */
4640 currently_expanding_to_rtl = 0;
4641
4642 FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb)
4643 {
4644 edge e;
4645 edge_iterator ei;
4646 for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
4647 {
4648 /* Clear EDGE_EXECUTABLE. This flag is never used in the backend. */
4649 e->flags &= ~EDGE_EXECUTABLE;
4650
4651 /* At the moment not all abnormal edges match the RTL
4652 representation. It is safe to remove them here as
4653 find_many_sub_basic_blocks will rediscover them.
4654 In the future we should get this fixed properly. */
4655 if ((e->flags & EDGE_ABNORMAL)
4656 && !(e->flags & EDGE_SIBCALL))
4657 remove_edge (e);
4658 else
4659 ei_next (&ei);
4660 }
4661 }
4662
4663 blocks = sbitmap_alloc (last_basic_block);
4664 sbitmap_ones (blocks);
4665 find_many_sub_basic_blocks (blocks);
4666 sbitmap_free (blocks);
4667 purge_all_dead_edges ();
4668
4669 compact_blocks ();
4670
4671 expand_stack_alignment ();
4672
4673 #ifdef ENABLE_CHECKING
4674 verify_flow_info ();
4675 #endif
4676
4677 /* There's no need to defer outputting this function any more; we
4678 know we want to output it. */
4679 DECL_DEFER_OUTPUT (current_function_decl) = 0;
4680
4681 /* Now that we're done expanding trees to RTL, we shouldn't have any
4682 more CONCATs anywhere. */
4683 generating_concat_p = 0;
4684
4685 if (dump_file)
4686 {
4687 fprintf (dump_file,
4688 "\n\n;;\n;; Full RTL generated for this function:\n;;\n");
4689 /* And the pass manager will dump RTL for us. */
4690 }
4691
4692 /* If we're emitting a nested function, make sure its parent gets
4693 emitted as well. Doing otherwise confuses debug info. */
4694 {
4695 tree parent;
4696 for (parent = DECL_CONTEXT (current_function_decl);
4697 parent != NULL_TREE;
4698 parent = get_containing_scope (parent))
4699 if (TREE_CODE (parent) == FUNCTION_DECL)
4700 TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (parent)) = 1;
4701 }
4702
4703 /* We are now committed to emitting code for this function. Do any
4704 preparation, such as emitting abstract debug info for the inline
4705 before it gets mangled by optimization. */
4706 if (cgraph_function_possibly_inlined_p (current_function_decl))
4707 (*debug_hooks->outlining_inline_function) (current_function_decl);
4708
4709 TREE_ASM_WRITTEN (current_function_decl) = 1;
4710
4711 /* After expanding, the return labels are no longer needed. */
4712 return_label = NULL;
4713 naked_return_label = NULL;
4714
4715 /* After expanding, the tm_restart map is no longer needed. */
4716 if (cfun->gimple_df->tm_restart)
4717 {
4718 htab_delete (cfun->gimple_df->tm_restart);
4719 cfun->gimple_df->tm_restart = NULL;
4720 }
4721
4722 /* Tag the blocks with a depth number so that change_scope can find
4723 the common parent easily. */
4724 set_block_levels (DECL_INITIAL (cfun->decl), 0);
4725 default_rtl_profile ();
4726 timevar_pop (TV_POST_EXPAND);
4727 return 0;
4728 }
4729
4730 struct rtl_opt_pass pass_expand =
4731 {
4732 {
4733 RTL_PASS,
4734 "expand", /* name */
4735 NULL, /* gate */
4736 gimple_expand_cfg, /* execute */
4737 NULL, /* sub */
4738 NULL, /* next */
4739 0, /* static_pass_number */
4740 TV_EXPAND, /* tv_id */
4741 PROP_ssa | PROP_gimple_leh | PROP_cfg
4742 | PROP_gimple_lcx, /* properties_required */
4743 PROP_rtl, /* properties_provided */
4744 PROP_ssa | PROP_trees, /* properties_destroyed */
4745 TODO_verify_ssa | TODO_verify_flow
4746 | TODO_verify_stmts, /* todo_flags_start */
4747 TODO_ggc_collect /* todo_flags_finish */
4748 }
4749 };
4750