PR c++/61339 - add mismatch between struct and class [-Wmismatched-tags] to non-bugs
[gcc.git] / gcc / function.c
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2019 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 /* This file handles the generation of rtl code from tree structure
21 at the level of the function as a whole.
22 It creates the rtl expressions for parameters and auto variables
23 and has full responsibility for allocating stack slots.
24
25 `expand_function_start' is called at the beginning of a function,
26 before the function body is parsed, and `expand_function_end' is
27 called after parsing the body.
28
29 Call `assign_stack_local' to allocate a stack slot for a local variable.
30 This is usually done during the RTL generation for the function body,
31 but it can also be done in the reload pass when a pseudo-register does
32 not get a hard register. */
33
34 #include "config.h"
35 #include "system.h"
36 #include "coretypes.h"
37 #include "backend.h"
38 #include "target.h"
39 #include "rtl.h"
40 #include "tree.h"
41 #include "gimple-expr.h"
42 #include "cfghooks.h"
43 #include "df.h"
44 #include "memmodel.h"
45 #include "tm_p.h"
46 #include "stringpool.h"
47 #include "expmed.h"
48 #include "optabs.h"
49 #include "regs.h"
50 #include "emit-rtl.h"
51 #include "recog.h"
52 #include "rtl-error.h"
53 #include "alias.h"
54 #include "fold-const.h"
55 #include "stor-layout.h"
56 #include "varasm.h"
57 #include "except.h"
58 #include "dojump.h"
59 #include "explow.h"
60 #include "calls.h"
61 #include "expr.h"
62 #include "optabs-tree.h"
63 #include "output.h"
64 #include "langhooks.h"
65 #include "common/common-target.h"
66 #include "gimplify.h"
67 #include "tree-pass.h"
68 #include "cfgrtl.h"
69 #include "cfganal.h"
70 #include "cfgbuild.h"
71 #include "cfgcleanup.h"
72 #include "cfgexpand.h"
73 #include "shrink-wrap.h"
74 #include "toplev.h"
75 #include "rtl-iter.h"
76 #include "tree-dfa.h"
77 #include "tree-ssa.h"
78 #include "stringpool.h"
79 #include "attribs.h"
80 #include "gimple.h"
81 #include "options.h"
82
83 /* So we can assign to cfun in this file. */
84 #undef cfun
85
86 #ifndef STACK_ALIGNMENT_NEEDED
87 #define STACK_ALIGNMENT_NEEDED 1
88 #endif
89
90 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
91
92 /* Round a value to the lowest integer less than it that is a multiple of
93 the required alignment. Avoid using division in case the value is
94 negative. Assume the alignment is a power of two. */
95 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
96
97 /* Similar, but round to the next highest integer that meets the
98 alignment. */
99 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
100
101 /* Nonzero once virtual register instantiation has been done.
102 assign_stack_local uses frame_pointer_rtx when this is nonzero.
103 calls.c:emit_library_call_value_1 uses it to set up
104 post-instantiation libcalls. */
105 int virtuals_instantiated;
106
107 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
108 static GTY(()) int funcdef_no;
109
110 /* These variables hold pointers to functions to create and destroy
111 target specific, per-function data structures. */
112 struct machine_function * (*init_machine_status) (void);
113
114 /* The currently compiled function. */
115 struct function *cfun = 0;
116
117 /* These hashes record the prologue and epilogue insns. */
118
119 struct insn_cache_hasher : ggc_cache_ptr_hash<rtx_def>
120 {
121 static hashval_t hash (rtx x) { return htab_hash_pointer (x); }
122 static bool equal (rtx a, rtx b) { return a == b; }
123 };
124
125 static GTY((cache))
126 hash_table<insn_cache_hasher> *prologue_insn_hash;
127 static GTY((cache))
128 hash_table<insn_cache_hasher> *epilogue_insn_hash;
129 \f
130
131 hash_table<used_type_hasher> *types_used_by_vars_hash = NULL;
132 vec<tree, va_gc> *types_used_by_cur_var_decl;
133
134 /* Forward declarations. */
135
136 static struct temp_slot *find_temp_slot_from_address (rtx);
137 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
138 static void pad_below (struct args_size *, machine_mode, tree);
139 static void reorder_blocks_1 (rtx_insn *, tree, vec<tree> *);
140 static int all_blocks (tree, tree *);
141 static tree *get_block_vector (tree, int *);
142 extern tree debug_find_var_in_block_tree (tree, tree);
143 /* We always define `record_insns' even if it's not used so that we
144 can always export `prologue_epilogue_contains'. */
145 static void record_insns (rtx_insn *, rtx, hash_table<insn_cache_hasher> **)
146 ATTRIBUTE_UNUSED;
147 static bool contains (const rtx_insn *, hash_table<insn_cache_hasher> *);
148 static void prepare_function_start (void);
149 static void do_clobber_return_reg (rtx, void *);
150 static void do_use_return_reg (rtx, void *);
151
152 \f
153 /* Stack of nested functions. */
154 /* Keep track of the cfun stack. */
155
156 static vec<function *> function_context_stack;
157
158 /* Save the current context for compilation of a nested function.
159 This is called from language-specific code. */
160
161 void
162 push_function_context (void)
163 {
164 if (cfun == 0)
165 allocate_struct_function (NULL, false);
166
167 function_context_stack.safe_push (cfun);
168 set_cfun (NULL);
169 }
170
171 /* Restore the last saved context, at the end of a nested function.
172 This function is called from language-specific code. */
173
174 void
175 pop_function_context (void)
176 {
177 struct function *p = function_context_stack.pop ();
178 set_cfun (p);
179 current_function_decl = p->decl;
180
181 /* Reset variables that have known state during rtx generation. */
182 virtuals_instantiated = 0;
183 generating_concat_p = 1;
184 }
185
186 /* Clear out all parts of the state in F that can safely be discarded
187 after the function has been parsed, but not compiled, to let
188 garbage collection reclaim the memory. */
189
190 void
191 free_after_parsing (struct function *f)
192 {
193 f->language = 0;
194 }
195
196 /* Clear out all parts of the state in F that can safely be discarded
197 after the function has been compiled, to let garbage collection
198 reclaim the memory. */
199
200 void
201 free_after_compilation (struct function *f)
202 {
203 prologue_insn_hash = NULL;
204 epilogue_insn_hash = NULL;
205
206 free (crtl->emit.regno_pointer_align);
207
208 memset (crtl, 0, sizeof (struct rtl_data));
209 f->eh = NULL;
210 f->machine = NULL;
211 f->cfg = NULL;
212 f->curr_properties &= ~PROP_cfg;
213
214 regno_reg_rtx = NULL;
215 }
216 \f
217 /* Return size needed for stack frame based on slots so far allocated.
218 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
219 the caller may have to do that. */
220
221 poly_int64
222 get_frame_size (void)
223 {
224 if (FRAME_GROWS_DOWNWARD)
225 return -frame_offset;
226 else
227 return frame_offset;
228 }
229
230 /* Issue an error message and return TRUE if frame OFFSET overflows in
231 the signed target pointer arithmetics for function FUNC. Otherwise
232 return FALSE. */
233
234 bool
235 frame_offset_overflow (poly_int64 offset, tree func)
236 {
237 poly_uint64 size = FRAME_GROWS_DOWNWARD ? -offset : offset;
238 unsigned HOST_WIDE_INT limit
239 = ((HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (Pmode) - 1))
240 /* Leave room for the fixed part of the frame. */
241 - 64 * UNITS_PER_WORD);
242
243 if (!coeffs_in_range_p (size, 0U, limit))
244 {
245 unsigned HOST_WIDE_INT hwisize;
246 if (size.is_constant (&hwisize))
247 error_at (DECL_SOURCE_LOCATION (func),
248 "total size of local objects %wu exceeds maximum %wu",
249 hwisize, limit);
250 else
251 error_at (DECL_SOURCE_LOCATION (func),
252 "total size of local objects exceeds maximum %wu",
253 limit);
254 return true;
255 }
256
257 return false;
258 }
259
260 /* Return the minimum spill slot alignment for a register of mode MODE. */
261
262 unsigned int
263 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED)
264 {
265 return STACK_SLOT_ALIGNMENT (NULL_TREE, mode, GET_MODE_ALIGNMENT (mode));
266 }
267
268 /* Return stack slot alignment in bits for TYPE and MODE. */
269
270 static unsigned int
271 get_stack_local_alignment (tree type, machine_mode mode)
272 {
273 unsigned int alignment;
274
275 if (mode == BLKmode)
276 alignment = BIGGEST_ALIGNMENT;
277 else
278 alignment = GET_MODE_ALIGNMENT (mode);
279
280 /* Allow the frond-end to (possibly) increase the alignment of this
281 stack slot. */
282 if (! type)
283 type = lang_hooks.types.type_for_mode (mode, 0);
284
285 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
286 }
287
288 /* Determine whether it is possible to fit a stack slot of size SIZE and
289 alignment ALIGNMENT into an area in the stack frame that starts at
290 frame offset START and has a length of LENGTH. If so, store the frame
291 offset to be used for the stack slot in *POFFSET and return true;
292 return false otherwise. This function will extend the frame size when
293 given a start/length pair that lies at the end of the frame. */
294
295 static bool
296 try_fit_stack_local (poly_int64 start, poly_int64 length,
297 poly_int64 size, unsigned int alignment,
298 poly_int64_pod *poffset)
299 {
300 poly_int64 this_frame_offset;
301 int frame_off, frame_alignment, frame_phase;
302
303 /* Calculate how many bytes the start of local variables is off from
304 stack alignment. */
305 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
306 frame_off = targetm.starting_frame_offset () % frame_alignment;
307 frame_phase = frame_off ? frame_alignment - frame_off : 0;
308
309 /* Round the frame offset to the specified alignment. */
310
311 if (FRAME_GROWS_DOWNWARD)
312 this_frame_offset
313 = (aligned_lower_bound (start + length - size - frame_phase, alignment)
314 + frame_phase);
315 else
316 this_frame_offset
317 = aligned_upper_bound (start - frame_phase, alignment) + frame_phase;
318
319 /* See if it fits. If this space is at the edge of the frame,
320 consider extending the frame to make it fit. Our caller relies on
321 this when allocating a new slot. */
322 if (maybe_lt (this_frame_offset, start))
323 {
324 if (known_eq (frame_offset, start))
325 frame_offset = this_frame_offset;
326 else
327 return false;
328 }
329 else if (maybe_gt (this_frame_offset + size, start + length))
330 {
331 if (known_eq (frame_offset, start + length))
332 frame_offset = this_frame_offset + size;
333 else
334 return false;
335 }
336
337 *poffset = this_frame_offset;
338 return true;
339 }
340
341 /* Create a new frame_space structure describing free space in the stack
342 frame beginning at START and ending at END, and chain it into the
343 function's frame_space_list. */
344
345 static void
346 add_frame_space (poly_int64 start, poly_int64 end)
347 {
348 struct frame_space *space = ggc_alloc<frame_space> ();
349 space->next = crtl->frame_space_list;
350 crtl->frame_space_list = space;
351 space->start = start;
352 space->length = end - start;
353 }
354
355 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
356 with machine mode MODE.
357
358 ALIGN controls the amount of alignment for the address of the slot:
359 0 means according to MODE,
360 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
361 -2 means use BITS_PER_UNIT,
362 positive specifies alignment boundary in bits.
363
364 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
365 alignment and ASLK_RECORD_PAD bit set if we should remember
366 extra space we allocated for alignment purposes. When we are
367 called from assign_stack_temp_for_type, it is not set so we don't
368 track the same stack slot in two independent lists.
369
370 We do not round to stack_boundary here. */
371
372 rtx
373 assign_stack_local_1 (machine_mode mode, poly_int64 size,
374 int align, int kind)
375 {
376 rtx x, addr;
377 poly_int64 bigend_correction = 0;
378 poly_int64 slot_offset = 0, old_frame_offset;
379 unsigned int alignment, alignment_in_bits;
380
381 if (align == 0)
382 {
383 alignment = get_stack_local_alignment (NULL, mode);
384 alignment /= BITS_PER_UNIT;
385 }
386 else if (align == -1)
387 {
388 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
389 size = aligned_upper_bound (size, alignment);
390 }
391 else if (align == -2)
392 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
393 else
394 alignment = align / BITS_PER_UNIT;
395
396 alignment_in_bits = alignment * BITS_PER_UNIT;
397
398 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
399 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
400 {
401 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
402 alignment = MAX_SUPPORTED_STACK_ALIGNMENT / BITS_PER_UNIT;
403 }
404
405 if (SUPPORTS_STACK_ALIGNMENT)
406 {
407 if (crtl->stack_alignment_estimated < alignment_in_bits)
408 {
409 if (!crtl->stack_realign_processed)
410 crtl->stack_alignment_estimated = alignment_in_bits;
411 else
412 {
413 /* If stack is realigned and stack alignment value
414 hasn't been finalized, it is OK not to increase
415 stack_alignment_estimated. The bigger alignment
416 requirement is recorded in stack_alignment_needed
417 below. */
418 gcc_assert (!crtl->stack_realign_finalized);
419 if (!crtl->stack_realign_needed)
420 {
421 /* It is OK to reduce the alignment as long as the
422 requested size is 0 or the estimated stack
423 alignment >= mode alignment. */
424 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
425 || known_eq (size, 0)
426 || (crtl->stack_alignment_estimated
427 >= GET_MODE_ALIGNMENT (mode)));
428 alignment_in_bits = crtl->stack_alignment_estimated;
429 alignment = alignment_in_bits / BITS_PER_UNIT;
430 }
431 }
432 }
433 }
434
435 if (crtl->stack_alignment_needed < alignment_in_bits)
436 crtl->stack_alignment_needed = alignment_in_bits;
437 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
438 crtl->max_used_stack_slot_alignment = alignment_in_bits;
439
440 if (mode != BLKmode || maybe_ne (size, 0))
441 {
442 if (kind & ASLK_RECORD_PAD)
443 {
444 struct frame_space **psp;
445
446 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
447 {
448 struct frame_space *space = *psp;
449 if (!try_fit_stack_local (space->start, space->length, size,
450 alignment, &slot_offset))
451 continue;
452 *psp = space->next;
453 if (known_gt (slot_offset, space->start))
454 add_frame_space (space->start, slot_offset);
455 if (known_lt (slot_offset + size, space->start + space->length))
456 add_frame_space (slot_offset + size,
457 space->start + space->length);
458 goto found_space;
459 }
460 }
461 }
462 else if (!STACK_ALIGNMENT_NEEDED)
463 {
464 slot_offset = frame_offset;
465 goto found_space;
466 }
467
468 old_frame_offset = frame_offset;
469
470 if (FRAME_GROWS_DOWNWARD)
471 {
472 frame_offset -= size;
473 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
474
475 if (kind & ASLK_RECORD_PAD)
476 {
477 if (known_gt (slot_offset, frame_offset))
478 add_frame_space (frame_offset, slot_offset);
479 if (known_lt (slot_offset + size, old_frame_offset))
480 add_frame_space (slot_offset + size, old_frame_offset);
481 }
482 }
483 else
484 {
485 frame_offset += size;
486 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
487
488 if (kind & ASLK_RECORD_PAD)
489 {
490 if (known_gt (slot_offset, old_frame_offset))
491 add_frame_space (old_frame_offset, slot_offset);
492 if (known_lt (slot_offset + size, frame_offset))
493 add_frame_space (slot_offset + size, frame_offset);
494 }
495 }
496
497 found_space:
498 /* On a big-endian machine, if we are allocating more space than we will use,
499 use the least significant bytes of those that are allocated. */
500 if (mode != BLKmode)
501 {
502 /* The slot size can sometimes be smaller than the mode size;
503 e.g. the rs6000 port allocates slots with a vector mode
504 that have the size of only one element. However, the slot
505 size must always be ordered wrt to the mode size, in the
506 same way as for a subreg. */
507 gcc_checking_assert (ordered_p (GET_MODE_SIZE (mode), size));
508 if (BYTES_BIG_ENDIAN && maybe_lt (GET_MODE_SIZE (mode), size))
509 bigend_correction = size - GET_MODE_SIZE (mode);
510 }
511
512 /* If we have already instantiated virtual registers, return the actual
513 address relative to the frame pointer. */
514 if (virtuals_instantiated)
515 addr = plus_constant (Pmode, frame_pointer_rtx,
516 trunc_int_for_mode
517 (slot_offset + bigend_correction
518 + targetm.starting_frame_offset (), Pmode));
519 else
520 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
521 trunc_int_for_mode
522 (slot_offset + bigend_correction,
523 Pmode));
524
525 x = gen_rtx_MEM (mode, addr);
526 set_mem_align (x, alignment_in_bits);
527 MEM_NOTRAP_P (x) = 1;
528
529 vec_safe_push (stack_slot_list, x);
530
531 if (frame_offset_overflow (frame_offset, current_function_decl))
532 frame_offset = 0;
533
534 return x;
535 }
536
537 /* Wrap up assign_stack_local_1 with last parameter as false. */
538
539 rtx
540 assign_stack_local (machine_mode mode, poly_int64 size, int align)
541 {
542 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
543 }
544 \f
545 /* In order to evaluate some expressions, such as function calls returning
546 structures in memory, we need to temporarily allocate stack locations.
547 We record each allocated temporary in the following structure.
548
549 Associated with each temporary slot is a nesting level. When we pop up
550 one level, all temporaries associated with the previous level are freed.
551 Normally, all temporaries are freed after the execution of the statement
552 in which they were created. However, if we are inside a ({...}) grouping,
553 the result may be in a temporary and hence must be preserved. If the
554 result could be in a temporary, we preserve it if we can determine which
555 one it is in. If we cannot determine which temporary may contain the
556 result, all temporaries are preserved. A temporary is preserved by
557 pretending it was allocated at the previous nesting level. */
558
559 class GTY(()) temp_slot {
560 public:
561 /* Points to next temporary slot. */
562 struct temp_slot *next;
563 /* Points to previous temporary slot. */
564 struct temp_slot *prev;
565 /* The rtx to used to reference the slot. */
566 rtx slot;
567 /* The size, in units, of the slot. */
568 poly_int64 size;
569 /* The type of the object in the slot, or zero if it doesn't correspond
570 to a type. We use this to determine whether a slot can be reused.
571 It can be reused if objects of the type of the new slot will always
572 conflict with objects of the type of the old slot. */
573 tree type;
574 /* The alignment (in bits) of the slot. */
575 unsigned int align;
576 /* Nonzero if this temporary is currently in use. */
577 char in_use;
578 /* Nesting level at which this slot is being used. */
579 int level;
580 /* The offset of the slot from the frame_pointer, including extra space
581 for alignment. This info is for combine_temp_slots. */
582 poly_int64 base_offset;
583 /* The size of the slot, including extra space for alignment. This
584 info is for combine_temp_slots. */
585 poly_int64 full_size;
586 };
587
588 /* Entry for the below hash table. */
589 struct GTY((for_user)) temp_slot_address_entry {
590 hashval_t hash;
591 rtx address;
592 struct temp_slot *temp_slot;
593 };
594
595 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
596 {
597 static hashval_t hash (temp_slot_address_entry *);
598 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
599 };
600
601 /* A table of addresses that represent a stack slot. The table is a mapping
602 from address RTXen to a temp slot. */
603 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
604 static size_t n_temp_slots_in_use;
605
606 /* Removes temporary slot TEMP from LIST. */
607
608 static void
609 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
610 {
611 if (temp->next)
612 temp->next->prev = temp->prev;
613 if (temp->prev)
614 temp->prev->next = temp->next;
615 else
616 *list = temp->next;
617
618 temp->prev = temp->next = NULL;
619 }
620
621 /* Inserts temporary slot TEMP to LIST. */
622
623 static void
624 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
625 {
626 temp->next = *list;
627 if (*list)
628 (*list)->prev = temp;
629 temp->prev = NULL;
630 *list = temp;
631 }
632
633 /* Returns the list of used temp slots at LEVEL. */
634
635 static struct temp_slot **
636 temp_slots_at_level (int level)
637 {
638 if (level >= (int) vec_safe_length (used_temp_slots))
639 vec_safe_grow_cleared (used_temp_slots, level + 1);
640
641 return &(*used_temp_slots)[level];
642 }
643
644 /* Returns the maximal temporary slot level. */
645
646 static int
647 max_slot_level (void)
648 {
649 if (!used_temp_slots)
650 return -1;
651
652 return used_temp_slots->length () - 1;
653 }
654
655 /* Moves temporary slot TEMP to LEVEL. */
656
657 static void
658 move_slot_to_level (struct temp_slot *temp, int level)
659 {
660 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
661 insert_slot_to_list (temp, temp_slots_at_level (level));
662 temp->level = level;
663 }
664
665 /* Make temporary slot TEMP available. */
666
667 static void
668 make_slot_available (struct temp_slot *temp)
669 {
670 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
671 insert_slot_to_list (temp, &avail_temp_slots);
672 temp->in_use = 0;
673 temp->level = -1;
674 n_temp_slots_in_use--;
675 }
676
677 /* Compute the hash value for an address -> temp slot mapping.
678 The value is cached on the mapping entry. */
679 static hashval_t
680 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
681 {
682 int do_not_record = 0;
683 return hash_rtx (t->address, GET_MODE (t->address),
684 &do_not_record, NULL, false);
685 }
686
687 /* Return the hash value for an address -> temp slot mapping. */
688 hashval_t
689 temp_address_hasher::hash (temp_slot_address_entry *t)
690 {
691 return t->hash;
692 }
693
694 /* Compare two address -> temp slot mapping entries. */
695 bool
696 temp_address_hasher::equal (temp_slot_address_entry *t1,
697 temp_slot_address_entry *t2)
698 {
699 return exp_equiv_p (t1->address, t2->address, 0, true);
700 }
701
702 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
703 static void
704 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
705 {
706 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
707 t->address = address;
708 t->temp_slot = temp_slot;
709 t->hash = temp_slot_address_compute_hash (t);
710 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
711 }
712
713 /* Remove an address -> temp slot mapping entry if the temp slot is
714 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
715 int
716 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
717 {
718 const struct temp_slot_address_entry *t = *slot;
719 if (! t->temp_slot->in_use)
720 temp_slot_address_table->clear_slot (slot);
721 return 1;
722 }
723
724 /* Remove all mappings of addresses to unused temp slots. */
725 static void
726 remove_unused_temp_slot_addresses (void)
727 {
728 /* Use quicker clearing if there aren't any active temp slots. */
729 if (n_temp_slots_in_use)
730 temp_slot_address_table->traverse
731 <void *, remove_unused_temp_slot_addresses_1> (NULL);
732 else
733 temp_slot_address_table->empty ();
734 }
735
736 /* Find the temp slot corresponding to the object at address X. */
737
738 static struct temp_slot *
739 find_temp_slot_from_address (rtx x)
740 {
741 struct temp_slot *p;
742 struct temp_slot_address_entry tmp, *t;
743
744 /* First try the easy way:
745 See if X exists in the address -> temp slot mapping. */
746 tmp.address = x;
747 tmp.temp_slot = NULL;
748 tmp.hash = temp_slot_address_compute_hash (&tmp);
749 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
750 if (t)
751 return t->temp_slot;
752
753 /* If we have a sum involving a register, see if it points to a temp
754 slot. */
755 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
756 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
757 return p;
758 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
759 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
760 return p;
761
762 /* Last resort: Address is a virtual stack var address. */
763 poly_int64 offset;
764 if (strip_offset (x, &offset) == virtual_stack_vars_rtx)
765 {
766 int i;
767 for (i = max_slot_level (); i >= 0; i--)
768 for (p = *temp_slots_at_level (i); p; p = p->next)
769 if (known_in_range_p (offset, p->base_offset, p->full_size))
770 return p;
771 }
772
773 return NULL;
774 }
775 \f
776 /* Allocate a temporary stack slot and record it for possible later
777 reuse.
778
779 MODE is the machine mode to be given to the returned rtx.
780
781 SIZE is the size in units of the space required. We do no rounding here
782 since assign_stack_local will do any required rounding.
783
784 TYPE is the type that will be used for the stack slot. */
785
786 rtx
787 assign_stack_temp_for_type (machine_mode mode, poly_int64 size, tree type)
788 {
789 unsigned int align;
790 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
791 rtx slot;
792
793 gcc_assert (known_size_p (size));
794
795 align = get_stack_local_alignment (type, mode);
796
797 /* Try to find an available, already-allocated temporary of the proper
798 mode which meets the size and alignment requirements. Choose the
799 smallest one with the closest alignment.
800
801 If assign_stack_temp is called outside of the tree->rtl expansion,
802 we cannot reuse the stack slots (that may still refer to
803 VIRTUAL_STACK_VARS_REGNUM). */
804 if (!virtuals_instantiated)
805 {
806 for (p = avail_temp_slots; p; p = p->next)
807 {
808 if (p->align >= align
809 && known_ge (p->size, size)
810 && GET_MODE (p->slot) == mode
811 && objects_must_conflict_p (p->type, type)
812 && (best_p == 0
813 || (known_eq (best_p->size, p->size)
814 ? best_p->align > p->align
815 : known_ge (best_p->size, p->size))))
816 {
817 if (p->align == align && known_eq (p->size, size))
818 {
819 selected = p;
820 cut_slot_from_list (selected, &avail_temp_slots);
821 best_p = 0;
822 break;
823 }
824 best_p = p;
825 }
826 }
827 }
828
829 /* Make our best, if any, the one to use. */
830 if (best_p)
831 {
832 selected = best_p;
833 cut_slot_from_list (selected, &avail_temp_slots);
834
835 /* If there are enough aligned bytes left over, make them into a new
836 temp_slot so that the extra bytes don't get wasted. Do this only
837 for BLKmode slots, so that we can be sure of the alignment. */
838 if (GET_MODE (best_p->slot) == BLKmode)
839 {
840 int alignment = best_p->align / BITS_PER_UNIT;
841 poly_int64 rounded_size = aligned_upper_bound (size, alignment);
842
843 if (known_ge (best_p->size - rounded_size, alignment))
844 {
845 p = ggc_alloc<temp_slot> ();
846 p->in_use = 0;
847 p->size = best_p->size - rounded_size;
848 p->base_offset = best_p->base_offset + rounded_size;
849 p->full_size = best_p->full_size - rounded_size;
850 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
851 p->align = best_p->align;
852 p->type = best_p->type;
853 insert_slot_to_list (p, &avail_temp_slots);
854
855 vec_safe_push (stack_slot_list, p->slot);
856
857 best_p->size = rounded_size;
858 best_p->full_size = rounded_size;
859 }
860 }
861 }
862
863 /* If we still didn't find one, make a new temporary. */
864 if (selected == 0)
865 {
866 poly_int64 frame_offset_old = frame_offset;
867
868 p = ggc_alloc<temp_slot> ();
869
870 /* We are passing an explicit alignment request to assign_stack_local.
871 One side effect of that is assign_stack_local will not round SIZE
872 to ensure the frame offset remains suitably aligned.
873
874 So for requests which depended on the rounding of SIZE, we go ahead
875 and round it now. We also make sure ALIGNMENT is at least
876 BIGGEST_ALIGNMENT. */
877 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
878 p->slot = assign_stack_local_1 (mode,
879 (mode == BLKmode
880 ? aligned_upper_bound (size,
881 (int) align
882 / BITS_PER_UNIT)
883 : size),
884 align, 0);
885
886 p->align = align;
887
888 /* The following slot size computation is necessary because we don't
889 know the actual size of the temporary slot until assign_stack_local
890 has performed all the frame alignment and size rounding for the
891 requested temporary. Note that extra space added for alignment
892 can be either above or below this stack slot depending on which
893 way the frame grows. We include the extra space if and only if it
894 is above this slot. */
895 if (FRAME_GROWS_DOWNWARD)
896 p->size = frame_offset_old - frame_offset;
897 else
898 p->size = size;
899
900 /* Now define the fields used by combine_temp_slots. */
901 if (FRAME_GROWS_DOWNWARD)
902 {
903 p->base_offset = frame_offset;
904 p->full_size = frame_offset_old - frame_offset;
905 }
906 else
907 {
908 p->base_offset = frame_offset_old;
909 p->full_size = frame_offset - frame_offset_old;
910 }
911
912 selected = p;
913 }
914
915 p = selected;
916 p->in_use = 1;
917 p->type = type;
918 p->level = temp_slot_level;
919 n_temp_slots_in_use++;
920
921 pp = temp_slots_at_level (p->level);
922 insert_slot_to_list (p, pp);
923 insert_temp_slot_address (XEXP (p->slot, 0), p);
924
925 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
926 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
927 vec_safe_push (stack_slot_list, slot);
928
929 /* If we know the alias set for the memory that will be used, use
930 it. If there's no TYPE, then we don't know anything about the
931 alias set for the memory. */
932 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
933 set_mem_align (slot, align);
934
935 /* If a type is specified, set the relevant flags. */
936 if (type != 0)
937 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
938 MEM_NOTRAP_P (slot) = 1;
939
940 return slot;
941 }
942
943 /* Allocate a temporary stack slot and record it for possible later
944 reuse. First two arguments are same as in preceding function. */
945
946 rtx
947 assign_stack_temp (machine_mode mode, poly_int64 size)
948 {
949 return assign_stack_temp_for_type (mode, size, NULL_TREE);
950 }
951 \f
952 /* Assign a temporary.
953 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
954 and so that should be used in error messages. In either case, we
955 allocate of the given type.
956 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
957 it is 0 if a register is OK.
958 DONT_PROMOTE is 1 if we should not promote values in register
959 to wider modes. */
960
961 rtx
962 assign_temp (tree type_or_decl, int memory_required,
963 int dont_promote ATTRIBUTE_UNUSED)
964 {
965 tree type, decl;
966 machine_mode mode;
967 #ifdef PROMOTE_MODE
968 int unsignedp;
969 #endif
970
971 if (DECL_P (type_or_decl))
972 decl = type_or_decl, type = TREE_TYPE (decl);
973 else
974 decl = NULL, type = type_or_decl;
975
976 mode = TYPE_MODE (type);
977 #ifdef PROMOTE_MODE
978 unsignedp = TYPE_UNSIGNED (type);
979 #endif
980
981 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
982 end. See also create_tmp_var for the gimplification-time check. */
983 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
984
985 if (mode == BLKmode || memory_required)
986 {
987 poly_int64 size;
988 rtx tmp;
989
990 /* Unfortunately, we don't yet know how to allocate variable-sized
991 temporaries. However, sometimes we can find a fixed upper limit on
992 the size, so try that instead. */
993 if (!poly_int_tree_p (TYPE_SIZE_UNIT (type), &size))
994 size = max_int_size_in_bytes (type);
995
996 /* Zero sized arrays are a GNU C extension. Set size to 1 to avoid
997 problems with allocating the stack space. */
998 if (known_eq (size, 0))
999 size = 1;
1000
1001 /* The size of the temporary may be too large to fit into an integer. */
1002 /* ??? Not sure this should happen except for user silliness, so limit
1003 this to things that aren't compiler-generated temporaries. The
1004 rest of the time we'll die in assign_stack_temp_for_type. */
1005 if (decl
1006 && !known_size_p (size)
1007 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1008 {
1009 error ("size of variable %q+D is too large", decl);
1010 size = 1;
1011 }
1012
1013 tmp = assign_stack_temp_for_type (mode, size, type);
1014 return tmp;
1015 }
1016
1017 #ifdef PROMOTE_MODE
1018 if (! dont_promote)
1019 mode = promote_mode (type, mode, &unsignedp);
1020 #endif
1021
1022 return gen_reg_rtx (mode);
1023 }
1024 \f
1025 /* Combine temporary stack slots which are adjacent on the stack.
1026
1027 This allows for better use of already allocated stack space. This is only
1028 done for BLKmode slots because we can be sure that we won't have alignment
1029 problems in this case. */
1030
1031 static void
1032 combine_temp_slots (void)
1033 {
1034 struct temp_slot *p, *q, *next, *next_q;
1035 int num_slots;
1036
1037 /* We can't combine slots, because the information about which slot
1038 is in which alias set will be lost. */
1039 if (flag_strict_aliasing)
1040 return;
1041
1042 /* If there are a lot of temp slots, don't do anything unless
1043 high levels of optimization. */
1044 if (! flag_expensive_optimizations)
1045 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1046 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1047 return;
1048
1049 for (p = avail_temp_slots; p; p = next)
1050 {
1051 int delete_p = 0;
1052
1053 next = p->next;
1054
1055 if (GET_MODE (p->slot) != BLKmode)
1056 continue;
1057
1058 for (q = p->next; q; q = next_q)
1059 {
1060 int delete_q = 0;
1061
1062 next_q = q->next;
1063
1064 if (GET_MODE (q->slot) != BLKmode)
1065 continue;
1066
1067 if (known_eq (p->base_offset + p->full_size, q->base_offset))
1068 {
1069 /* Q comes after P; combine Q into P. */
1070 p->size += q->size;
1071 p->full_size += q->full_size;
1072 delete_q = 1;
1073 }
1074 else if (known_eq (q->base_offset + q->full_size, p->base_offset))
1075 {
1076 /* P comes after Q; combine P into Q. */
1077 q->size += p->size;
1078 q->full_size += p->full_size;
1079 delete_p = 1;
1080 break;
1081 }
1082 if (delete_q)
1083 cut_slot_from_list (q, &avail_temp_slots);
1084 }
1085
1086 /* Either delete P or advance past it. */
1087 if (delete_p)
1088 cut_slot_from_list (p, &avail_temp_slots);
1089 }
1090 }
1091 \f
1092 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1093 slot that previously was known by OLD_RTX. */
1094
1095 void
1096 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1097 {
1098 struct temp_slot *p;
1099
1100 if (rtx_equal_p (old_rtx, new_rtx))
1101 return;
1102
1103 p = find_temp_slot_from_address (old_rtx);
1104
1105 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1106 NEW_RTX is a register, see if one operand of the PLUS is a
1107 temporary location. If so, NEW_RTX points into it. Otherwise,
1108 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1109 in common between them. If so, try a recursive call on those
1110 values. */
1111 if (p == 0)
1112 {
1113 if (GET_CODE (old_rtx) != PLUS)
1114 return;
1115
1116 if (REG_P (new_rtx))
1117 {
1118 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1119 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1120 return;
1121 }
1122 else if (GET_CODE (new_rtx) != PLUS)
1123 return;
1124
1125 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1126 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1127 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1128 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1129 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1130 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1131 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1132 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1133
1134 return;
1135 }
1136
1137 /* Otherwise add an alias for the temp's address. */
1138 insert_temp_slot_address (new_rtx, p);
1139 }
1140
1141 /* If X could be a reference to a temporary slot, mark that slot as
1142 belonging to the to one level higher than the current level. If X
1143 matched one of our slots, just mark that one. Otherwise, we can't
1144 easily predict which it is, so upgrade all of them.
1145
1146 This is called when an ({...}) construct occurs and a statement
1147 returns a value in memory. */
1148
1149 void
1150 preserve_temp_slots (rtx x)
1151 {
1152 struct temp_slot *p = 0, *next;
1153
1154 if (x == 0)
1155 return;
1156
1157 /* If X is a register that is being used as a pointer, see if we have
1158 a temporary slot we know it points to. */
1159 if (REG_P (x) && REG_POINTER (x))
1160 p = find_temp_slot_from_address (x);
1161
1162 /* If X is not in memory or is at a constant address, it cannot be in
1163 a temporary slot. */
1164 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1165 return;
1166
1167 /* First see if we can find a match. */
1168 if (p == 0)
1169 p = find_temp_slot_from_address (XEXP (x, 0));
1170
1171 if (p != 0)
1172 {
1173 if (p->level == temp_slot_level)
1174 move_slot_to_level (p, temp_slot_level - 1);
1175 return;
1176 }
1177
1178 /* Otherwise, preserve all non-kept slots at this level. */
1179 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1180 {
1181 next = p->next;
1182 move_slot_to_level (p, temp_slot_level - 1);
1183 }
1184 }
1185
1186 /* Free all temporaries used so far. This is normally called at the
1187 end of generating code for a statement. */
1188
1189 void
1190 free_temp_slots (void)
1191 {
1192 struct temp_slot *p, *next;
1193 bool some_available = false;
1194
1195 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1196 {
1197 next = p->next;
1198 make_slot_available (p);
1199 some_available = true;
1200 }
1201
1202 if (some_available)
1203 {
1204 remove_unused_temp_slot_addresses ();
1205 combine_temp_slots ();
1206 }
1207 }
1208
1209 /* Push deeper into the nesting level for stack temporaries. */
1210
1211 void
1212 push_temp_slots (void)
1213 {
1214 temp_slot_level++;
1215 }
1216
1217 /* Pop a temporary nesting level. All slots in use in the current level
1218 are freed. */
1219
1220 void
1221 pop_temp_slots (void)
1222 {
1223 free_temp_slots ();
1224 temp_slot_level--;
1225 }
1226
1227 /* Initialize temporary slots. */
1228
1229 void
1230 init_temp_slots (void)
1231 {
1232 /* We have not allocated any temporaries yet. */
1233 avail_temp_slots = 0;
1234 vec_alloc (used_temp_slots, 0);
1235 temp_slot_level = 0;
1236 n_temp_slots_in_use = 0;
1237
1238 /* Set up the table to map addresses to temp slots. */
1239 if (! temp_slot_address_table)
1240 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1241 else
1242 temp_slot_address_table->empty ();
1243 }
1244 \f
1245 /* Functions and data structures to keep track of the values hard regs
1246 had at the start of the function. */
1247
1248 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1249 and has_hard_reg_initial_val.. */
1250 struct GTY(()) initial_value_pair {
1251 rtx hard_reg;
1252 rtx pseudo;
1253 };
1254 /* ??? This could be a VEC but there is currently no way to define an
1255 opaque VEC type. This could be worked around by defining struct
1256 initial_value_pair in function.h. */
1257 struct GTY(()) initial_value_struct {
1258 int num_entries;
1259 int max_entries;
1260 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1261 };
1262
1263 /* If a pseudo represents an initial hard reg (or expression), return
1264 it, else return NULL_RTX. */
1265
1266 rtx
1267 get_hard_reg_initial_reg (rtx reg)
1268 {
1269 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1270 int i;
1271
1272 if (ivs == 0)
1273 return NULL_RTX;
1274
1275 for (i = 0; i < ivs->num_entries; i++)
1276 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1277 return ivs->entries[i].hard_reg;
1278
1279 return NULL_RTX;
1280 }
1281
1282 /* Make sure that there's a pseudo register of mode MODE that stores the
1283 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1284
1285 rtx
1286 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1287 {
1288 struct initial_value_struct *ivs;
1289 rtx rv;
1290
1291 rv = has_hard_reg_initial_val (mode, regno);
1292 if (rv)
1293 return rv;
1294
1295 ivs = crtl->hard_reg_initial_vals;
1296 if (ivs == 0)
1297 {
1298 ivs = ggc_alloc<initial_value_struct> ();
1299 ivs->num_entries = 0;
1300 ivs->max_entries = 5;
1301 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1302 crtl->hard_reg_initial_vals = ivs;
1303 }
1304
1305 if (ivs->num_entries >= ivs->max_entries)
1306 {
1307 ivs->max_entries += 5;
1308 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1309 ivs->max_entries);
1310 }
1311
1312 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1313 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1314
1315 return ivs->entries[ivs->num_entries++].pseudo;
1316 }
1317
1318 /* See if get_hard_reg_initial_val has been used to create a pseudo
1319 for the initial value of hard register REGNO in mode MODE. Return
1320 the associated pseudo if so, otherwise return NULL. */
1321
1322 rtx
1323 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1324 {
1325 struct initial_value_struct *ivs;
1326 int i;
1327
1328 ivs = crtl->hard_reg_initial_vals;
1329 if (ivs != 0)
1330 for (i = 0; i < ivs->num_entries; i++)
1331 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1332 && REGNO (ivs->entries[i].hard_reg) == regno)
1333 return ivs->entries[i].pseudo;
1334
1335 return NULL_RTX;
1336 }
1337
1338 unsigned int
1339 emit_initial_value_sets (void)
1340 {
1341 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1342 int i;
1343 rtx_insn *seq;
1344
1345 if (ivs == 0)
1346 return 0;
1347
1348 start_sequence ();
1349 for (i = 0; i < ivs->num_entries; i++)
1350 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1351 seq = get_insns ();
1352 end_sequence ();
1353
1354 emit_insn_at_entry (seq);
1355 return 0;
1356 }
1357
1358 /* Return the hardreg-pseudoreg initial values pair entry I and
1359 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1360 bool
1361 initial_value_entry (int i, rtx *hreg, rtx *preg)
1362 {
1363 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1364 if (!ivs || i >= ivs->num_entries)
1365 return false;
1366
1367 *hreg = ivs->entries[i].hard_reg;
1368 *preg = ivs->entries[i].pseudo;
1369 return true;
1370 }
1371 \f
1372 /* These routines are responsible for converting virtual register references
1373 to the actual hard register references once RTL generation is complete.
1374
1375 The following four variables are used for communication between the
1376 routines. They contain the offsets of the virtual registers from their
1377 respective hard registers. */
1378
1379 static poly_int64 in_arg_offset;
1380 static poly_int64 var_offset;
1381 static poly_int64 dynamic_offset;
1382 static poly_int64 out_arg_offset;
1383 static poly_int64 cfa_offset;
1384
1385 /* In most machines, the stack pointer register is equivalent to the bottom
1386 of the stack. */
1387
1388 #ifndef STACK_POINTER_OFFSET
1389 #define STACK_POINTER_OFFSET 0
1390 #endif
1391
1392 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1393 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1394 #endif
1395
1396 /* If not defined, pick an appropriate default for the offset of dynamically
1397 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1398 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1399
1400 #ifndef STACK_DYNAMIC_OFFSET
1401
1402 /* The bottom of the stack points to the actual arguments. If
1403 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1404 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1405 stack space for register parameters is not pushed by the caller, but
1406 rather part of the fixed stack areas and hence not included in
1407 `crtl->outgoing_args_size'. Nevertheless, we must allow
1408 for it when allocating stack dynamic objects. */
1409
1410 #ifdef INCOMING_REG_PARM_STACK_SPACE
1411 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1412 ((ACCUMULATE_OUTGOING_ARGS \
1413 ? (crtl->outgoing_args_size \
1414 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1415 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1416 : 0) + (STACK_POINTER_OFFSET))
1417 #else
1418 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1419 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : poly_int64 (0)) \
1420 + (STACK_POINTER_OFFSET))
1421 #endif
1422 #endif
1423
1424 \f
1425 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1426 is a virtual register, return the equivalent hard register and set the
1427 offset indirectly through the pointer. Otherwise, return 0. */
1428
1429 static rtx
1430 instantiate_new_reg (rtx x, poly_int64_pod *poffset)
1431 {
1432 rtx new_rtx;
1433 poly_int64 offset;
1434
1435 if (x == virtual_incoming_args_rtx)
1436 {
1437 if (stack_realign_drap)
1438 {
1439 /* Replace virtual_incoming_args_rtx with internal arg
1440 pointer if DRAP is used to realign stack. */
1441 new_rtx = crtl->args.internal_arg_pointer;
1442 offset = 0;
1443 }
1444 else
1445 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1446 }
1447 else if (x == virtual_stack_vars_rtx)
1448 new_rtx = frame_pointer_rtx, offset = var_offset;
1449 else if (x == virtual_stack_dynamic_rtx)
1450 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1451 else if (x == virtual_outgoing_args_rtx)
1452 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1453 else if (x == virtual_cfa_rtx)
1454 {
1455 #ifdef FRAME_POINTER_CFA_OFFSET
1456 new_rtx = frame_pointer_rtx;
1457 #else
1458 new_rtx = arg_pointer_rtx;
1459 #endif
1460 offset = cfa_offset;
1461 }
1462 else if (x == virtual_preferred_stack_boundary_rtx)
1463 {
1464 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1465 offset = 0;
1466 }
1467 else
1468 return NULL_RTX;
1469
1470 *poffset = offset;
1471 return new_rtx;
1472 }
1473
1474 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1475 registers present inside of *LOC. The expression is simplified,
1476 as much as possible, but is not to be considered "valid" in any sense
1477 implied by the target. Return true if any change is made. */
1478
1479 static bool
1480 instantiate_virtual_regs_in_rtx (rtx *loc)
1481 {
1482 if (!*loc)
1483 return false;
1484 bool changed = false;
1485 subrtx_ptr_iterator::array_type array;
1486 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1487 {
1488 rtx *loc = *iter;
1489 if (rtx x = *loc)
1490 {
1491 rtx new_rtx;
1492 poly_int64 offset;
1493 switch (GET_CODE (x))
1494 {
1495 case REG:
1496 new_rtx = instantiate_new_reg (x, &offset);
1497 if (new_rtx)
1498 {
1499 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1500 changed = true;
1501 }
1502 iter.skip_subrtxes ();
1503 break;
1504
1505 case PLUS:
1506 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1507 if (new_rtx)
1508 {
1509 XEXP (x, 0) = new_rtx;
1510 *loc = plus_constant (GET_MODE (x), x, offset, true);
1511 changed = true;
1512 iter.skip_subrtxes ();
1513 break;
1514 }
1515
1516 /* FIXME -- from old code */
1517 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1518 we can commute the PLUS and SUBREG because pointers into the
1519 frame are well-behaved. */
1520 break;
1521
1522 default:
1523 break;
1524 }
1525 }
1526 }
1527 return changed;
1528 }
1529
1530 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1531 matches the predicate for insn CODE operand OPERAND. */
1532
1533 static int
1534 safe_insn_predicate (int code, int operand, rtx x)
1535 {
1536 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1537 }
1538
1539 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1540 registers present inside of insn. The result will be a valid insn. */
1541
1542 static void
1543 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1544 {
1545 poly_int64 offset;
1546 int insn_code, i;
1547 bool any_change = false;
1548 rtx set, new_rtx, x;
1549 rtx_insn *seq;
1550
1551 /* There are some special cases to be handled first. */
1552 set = single_set (insn);
1553 if (set)
1554 {
1555 /* We're allowed to assign to a virtual register. This is interpreted
1556 to mean that the underlying register gets assigned the inverse
1557 transformation. This is used, for example, in the handling of
1558 non-local gotos. */
1559 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1560 if (new_rtx)
1561 {
1562 start_sequence ();
1563
1564 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1565 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1566 gen_int_mode (-offset, GET_MODE (new_rtx)));
1567 x = force_operand (x, new_rtx);
1568 if (x != new_rtx)
1569 emit_move_insn (new_rtx, x);
1570
1571 seq = get_insns ();
1572 end_sequence ();
1573
1574 emit_insn_before (seq, insn);
1575 delete_insn (insn);
1576 return;
1577 }
1578
1579 /* Handle a straight copy from a virtual register by generating a
1580 new add insn. The difference between this and falling through
1581 to the generic case is avoiding a new pseudo and eliminating a
1582 move insn in the initial rtl stream. */
1583 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1584 if (new_rtx
1585 && maybe_ne (offset, 0)
1586 && REG_P (SET_DEST (set))
1587 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1588 {
1589 start_sequence ();
1590
1591 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1592 gen_int_mode (offset,
1593 GET_MODE (SET_DEST (set))),
1594 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1595 if (x != SET_DEST (set))
1596 emit_move_insn (SET_DEST (set), x);
1597
1598 seq = get_insns ();
1599 end_sequence ();
1600
1601 emit_insn_before (seq, insn);
1602 delete_insn (insn);
1603 return;
1604 }
1605
1606 extract_insn (insn);
1607 insn_code = INSN_CODE (insn);
1608
1609 /* Handle a plus involving a virtual register by determining if the
1610 operands remain valid if they're modified in place. */
1611 poly_int64 delta;
1612 if (GET_CODE (SET_SRC (set)) == PLUS
1613 && recog_data.n_operands >= 3
1614 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1615 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1616 && poly_int_rtx_p (recog_data.operand[2], &delta)
1617 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1618 {
1619 offset += delta;
1620
1621 /* If the sum is zero, then replace with a plain move. */
1622 if (known_eq (offset, 0)
1623 && REG_P (SET_DEST (set))
1624 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1625 {
1626 start_sequence ();
1627 emit_move_insn (SET_DEST (set), new_rtx);
1628 seq = get_insns ();
1629 end_sequence ();
1630
1631 emit_insn_before (seq, insn);
1632 delete_insn (insn);
1633 return;
1634 }
1635
1636 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1637
1638 /* Using validate_change and apply_change_group here leaves
1639 recog_data in an invalid state. Since we know exactly what
1640 we want to check, do those two by hand. */
1641 if (safe_insn_predicate (insn_code, 1, new_rtx)
1642 && safe_insn_predicate (insn_code, 2, x))
1643 {
1644 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1645 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1646 any_change = true;
1647
1648 /* Fall through into the regular operand fixup loop in
1649 order to take care of operands other than 1 and 2. */
1650 }
1651 }
1652 }
1653 else
1654 {
1655 extract_insn (insn);
1656 insn_code = INSN_CODE (insn);
1657 }
1658
1659 /* In the general case, we expect virtual registers to appear only in
1660 operands, and then only as either bare registers or inside memories. */
1661 for (i = 0; i < recog_data.n_operands; ++i)
1662 {
1663 x = recog_data.operand[i];
1664 switch (GET_CODE (x))
1665 {
1666 case MEM:
1667 {
1668 rtx addr = XEXP (x, 0);
1669
1670 if (!instantiate_virtual_regs_in_rtx (&addr))
1671 continue;
1672
1673 start_sequence ();
1674 x = replace_equiv_address (x, addr, true);
1675 /* It may happen that the address with the virtual reg
1676 was valid (e.g. based on the virtual stack reg, which might
1677 be acceptable to the predicates with all offsets), whereas
1678 the address now isn't anymore, for instance when the address
1679 is still offsetted, but the base reg isn't virtual-stack-reg
1680 anymore. Below we would do a force_reg on the whole operand,
1681 but this insn might actually only accept memory. Hence,
1682 before doing that last resort, try to reload the address into
1683 a register, so this operand stays a MEM. */
1684 if (!safe_insn_predicate (insn_code, i, x))
1685 {
1686 addr = force_reg (GET_MODE (addr), addr);
1687 x = replace_equiv_address (x, addr, true);
1688 }
1689 seq = get_insns ();
1690 end_sequence ();
1691 if (seq)
1692 emit_insn_before (seq, insn);
1693 }
1694 break;
1695
1696 case REG:
1697 new_rtx = instantiate_new_reg (x, &offset);
1698 if (new_rtx == NULL)
1699 continue;
1700 if (known_eq (offset, 0))
1701 x = new_rtx;
1702 else
1703 {
1704 start_sequence ();
1705
1706 /* Careful, special mode predicates may have stuff in
1707 insn_data[insn_code].operand[i].mode that isn't useful
1708 to us for computing a new value. */
1709 /* ??? Recognize address_operand and/or "p" constraints
1710 to see if (plus new offset) is a valid before we put
1711 this through expand_simple_binop. */
1712 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1713 gen_int_mode (offset, GET_MODE (x)),
1714 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1715 seq = get_insns ();
1716 end_sequence ();
1717 emit_insn_before (seq, insn);
1718 }
1719 break;
1720
1721 case SUBREG:
1722 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1723 if (new_rtx == NULL)
1724 continue;
1725 if (maybe_ne (offset, 0))
1726 {
1727 start_sequence ();
1728 new_rtx = expand_simple_binop
1729 (GET_MODE (new_rtx), PLUS, new_rtx,
1730 gen_int_mode (offset, GET_MODE (new_rtx)),
1731 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1732 seq = get_insns ();
1733 end_sequence ();
1734 emit_insn_before (seq, insn);
1735 }
1736 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1737 GET_MODE (new_rtx), SUBREG_BYTE (x));
1738 gcc_assert (x);
1739 break;
1740
1741 default:
1742 continue;
1743 }
1744
1745 /* At this point, X contains the new value for the operand.
1746 Validate the new value vs the insn predicate. Note that
1747 asm insns will have insn_code -1 here. */
1748 if (!safe_insn_predicate (insn_code, i, x))
1749 {
1750 start_sequence ();
1751 if (REG_P (x))
1752 {
1753 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1754 x = copy_to_reg (x);
1755 }
1756 else
1757 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1758 seq = get_insns ();
1759 end_sequence ();
1760 if (seq)
1761 emit_insn_before (seq, insn);
1762 }
1763
1764 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1765 any_change = true;
1766 }
1767
1768 if (any_change)
1769 {
1770 /* Propagate operand changes into the duplicates. */
1771 for (i = 0; i < recog_data.n_dups; ++i)
1772 *recog_data.dup_loc[i]
1773 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1774
1775 /* Force re-recognition of the instruction for validation. */
1776 INSN_CODE (insn) = -1;
1777 }
1778
1779 if (asm_noperands (PATTERN (insn)) >= 0)
1780 {
1781 if (!check_asm_operands (PATTERN (insn)))
1782 {
1783 error_for_asm (insn, "impossible constraint in %<asm%>");
1784 /* For asm goto, instead of fixing up all the edges
1785 just clear the template and clear input operands
1786 (asm goto doesn't have any output operands). */
1787 if (JUMP_P (insn))
1788 {
1789 rtx asm_op = extract_asm_operands (PATTERN (insn));
1790 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1791 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1792 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1793 }
1794 else
1795 delete_insn (insn);
1796 }
1797 }
1798 else
1799 {
1800 if (recog_memoized (insn) < 0)
1801 fatal_insn_not_found (insn);
1802 }
1803 }
1804
1805 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1806 do any instantiation required. */
1807
1808 void
1809 instantiate_decl_rtl (rtx x)
1810 {
1811 rtx addr;
1812
1813 if (x == 0)
1814 return;
1815
1816 /* If this is a CONCAT, recurse for the pieces. */
1817 if (GET_CODE (x) == CONCAT)
1818 {
1819 instantiate_decl_rtl (XEXP (x, 0));
1820 instantiate_decl_rtl (XEXP (x, 1));
1821 return;
1822 }
1823
1824 /* If this is not a MEM, no need to do anything. Similarly if the
1825 address is a constant or a register that is not a virtual register. */
1826 if (!MEM_P (x))
1827 return;
1828
1829 addr = XEXP (x, 0);
1830 if (CONSTANT_P (addr)
1831 || (REG_P (addr)
1832 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1833 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1834 return;
1835
1836 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1837 }
1838
1839 /* Helper for instantiate_decls called via walk_tree: Process all decls
1840 in the given DECL_VALUE_EXPR. */
1841
1842 static tree
1843 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1844 {
1845 tree t = *tp;
1846 if (! EXPR_P (t))
1847 {
1848 *walk_subtrees = 0;
1849 if (DECL_P (t))
1850 {
1851 if (DECL_RTL_SET_P (t))
1852 instantiate_decl_rtl (DECL_RTL (t));
1853 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1854 && DECL_INCOMING_RTL (t))
1855 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1856 if ((VAR_P (t) || TREE_CODE (t) == RESULT_DECL)
1857 && DECL_HAS_VALUE_EXPR_P (t))
1858 {
1859 tree v = DECL_VALUE_EXPR (t);
1860 walk_tree (&v, instantiate_expr, NULL, NULL);
1861 }
1862 }
1863 }
1864 return NULL;
1865 }
1866
1867 /* Subroutine of instantiate_decls: Process all decls in the given
1868 BLOCK node and all its subblocks. */
1869
1870 static void
1871 instantiate_decls_1 (tree let)
1872 {
1873 tree t;
1874
1875 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1876 {
1877 if (DECL_RTL_SET_P (t))
1878 instantiate_decl_rtl (DECL_RTL (t));
1879 if (VAR_P (t) && DECL_HAS_VALUE_EXPR_P (t))
1880 {
1881 tree v = DECL_VALUE_EXPR (t);
1882 walk_tree (&v, instantiate_expr, NULL, NULL);
1883 }
1884 }
1885
1886 /* Process all subblocks. */
1887 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1888 instantiate_decls_1 (t);
1889 }
1890
1891 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1892 all virtual registers in their DECL_RTL's. */
1893
1894 static void
1895 instantiate_decls (tree fndecl)
1896 {
1897 tree decl;
1898 unsigned ix;
1899
1900 /* Process all parameters of the function. */
1901 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1902 {
1903 instantiate_decl_rtl (DECL_RTL (decl));
1904 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1905 if (DECL_HAS_VALUE_EXPR_P (decl))
1906 {
1907 tree v = DECL_VALUE_EXPR (decl);
1908 walk_tree (&v, instantiate_expr, NULL, NULL);
1909 }
1910 }
1911
1912 if ((decl = DECL_RESULT (fndecl))
1913 && TREE_CODE (decl) == RESULT_DECL)
1914 {
1915 if (DECL_RTL_SET_P (decl))
1916 instantiate_decl_rtl (DECL_RTL (decl));
1917 if (DECL_HAS_VALUE_EXPR_P (decl))
1918 {
1919 tree v = DECL_VALUE_EXPR (decl);
1920 walk_tree (&v, instantiate_expr, NULL, NULL);
1921 }
1922 }
1923
1924 /* Process the saved static chain if it exists. */
1925 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1926 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1927 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1928
1929 /* Now process all variables defined in the function or its subblocks. */
1930 if (DECL_INITIAL (fndecl))
1931 instantiate_decls_1 (DECL_INITIAL (fndecl));
1932
1933 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1934 if (DECL_RTL_SET_P (decl))
1935 instantiate_decl_rtl (DECL_RTL (decl));
1936 vec_free (cfun->local_decls);
1937 }
1938
1939 /* Pass through the INSNS of function FNDECL and convert virtual register
1940 references to hard register references. */
1941
1942 static unsigned int
1943 instantiate_virtual_regs (void)
1944 {
1945 rtx_insn *insn;
1946
1947 /* Compute the offsets to use for this function. */
1948 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1949 var_offset = targetm.starting_frame_offset ();
1950 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1951 out_arg_offset = STACK_POINTER_OFFSET;
1952 #ifdef FRAME_POINTER_CFA_OFFSET
1953 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1954 #else
1955 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1956 #endif
1957
1958 /* Initialize recognition, indicating that volatile is OK. */
1959 init_recog ();
1960
1961 /* Scan through all the insns, instantiating every virtual register still
1962 present. */
1963 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1964 if (INSN_P (insn))
1965 {
1966 /* These patterns in the instruction stream can never be recognized.
1967 Fortunately, they shouldn't contain virtual registers either. */
1968 if (GET_CODE (PATTERN (insn)) == USE
1969 || GET_CODE (PATTERN (insn)) == CLOBBER
1970 || GET_CODE (PATTERN (insn)) == ASM_INPUT
1971 || DEBUG_MARKER_INSN_P (insn))
1972 continue;
1973 else if (DEBUG_BIND_INSN_P (insn))
1974 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn));
1975 else
1976 instantiate_virtual_regs_in_insn (insn);
1977
1978 if (insn->deleted ())
1979 continue;
1980
1981 instantiate_virtual_regs_in_rtx (&REG_NOTES (insn));
1982
1983 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1984 if (CALL_P (insn))
1985 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1986 }
1987
1988 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1989 instantiate_decls (current_function_decl);
1990
1991 targetm.instantiate_decls ();
1992
1993 /* Indicate that, from now on, assign_stack_local should use
1994 frame_pointer_rtx. */
1995 virtuals_instantiated = 1;
1996
1997 return 0;
1998 }
1999
2000 namespace {
2001
2002 const pass_data pass_data_instantiate_virtual_regs =
2003 {
2004 RTL_PASS, /* type */
2005 "vregs", /* name */
2006 OPTGROUP_NONE, /* optinfo_flags */
2007 TV_NONE, /* tv_id */
2008 0, /* properties_required */
2009 0, /* properties_provided */
2010 0, /* properties_destroyed */
2011 0, /* todo_flags_start */
2012 0, /* todo_flags_finish */
2013 };
2014
2015 class pass_instantiate_virtual_regs : public rtl_opt_pass
2016 {
2017 public:
2018 pass_instantiate_virtual_regs (gcc::context *ctxt)
2019 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2020 {}
2021
2022 /* opt_pass methods: */
2023 virtual unsigned int execute (function *)
2024 {
2025 return instantiate_virtual_regs ();
2026 }
2027
2028 }; // class pass_instantiate_virtual_regs
2029
2030 } // anon namespace
2031
2032 rtl_opt_pass *
2033 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2034 {
2035 return new pass_instantiate_virtual_regs (ctxt);
2036 }
2037
2038 \f
2039 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2040 This means a type for which function calls must pass an address to the
2041 function or get an address back from the function.
2042 EXP may be a type node or an expression (whose type is tested). */
2043
2044 int
2045 aggregate_value_p (const_tree exp, const_tree fntype)
2046 {
2047 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2048 int i, regno, nregs;
2049 rtx reg;
2050
2051 if (fntype)
2052 switch (TREE_CODE (fntype))
2053 {
2054 case CALL_EXPR:
2055 {
2056 tree fndecl = get_callee_fndecl (fntype);
2057 if (fndecl)
2058 fntype = TREE_TYPE (fndecl);
2059 else if (CALL_EXPR_FN (fntype))
2060 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2061 else
2062 /* For internal functions, assume nothing needs to be
2063 returned in memory. */
2064 return 0;
2065 }
2066 break;
2067 case FUNCTION_DECL:
2068 fntype = TREE_TYPE (fntype);
2069 break;
2070 case FUNCTION_TYPE:
2071 case METHOD_TYPE:
2072 break;
2073 case IDENTIFIER_NODE:
2074 fntype = NULL_TREE;
2075 break;
2076 default:
2077 /* We don't expect other tree types here. */
2078 gcc_unreachable ();
2079 }
2080
2081 if (VOID_TYPE_P (type))
2082 return 0;
2083
2084 /* If a record should be passed the same as its first (and only) member
2085 don't pass it as an aggregate. */
2086 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2087 return aggregate_value_p (first_field (type), fntype);
2088
2089 /* If the front end has decided that this needs to be passed by
2090 reference, do so. */
2091 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2092 && DECL_BY_REFERENCE (exp))
2093 return 1;
2094
2095 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2096 if (fntype && TREE_ADDRESSABLE (fntype))
2097 return 1;
2098
2099 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2100 and thus can't be returned in registers. */
2101 if (TREE_ADDRESSABLE (type))
2102 return 1;
2103
2104 if (TYPE_EMPTY_P (type))
2105 return 0;
2106
2107 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2108 return 1;
2109
2110 if (targetm.calls.return_in_memory (type, fntype))
2111 return 1;
2112
2113 /* Make sure we have suitable call-clobbered regs to return
2114 the value in; if not, we must return it in memory. */
2115 reg = hard_function_value (type, 0, fntype, 0);
2116
2117 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2118 it is OK. */
2119 if (!REG_P (reg))
2120 return 0;
2121
2122 regno = REGNO (reg);
2123 nregs = hard_regno_nregs (regno, TYPE_MODE (type));
2124 for (i = 0; i < nregs; i++)
2125 if (! call_used_regs[regno + i])
2126 return 1;
2127
2128 return 0;
2129 }
2130 \f
2131 /* Return true if we should assign DECL a pseudo register; false if it
2132 should live on the local stack. */
2133
2134 bool
2135 use_register_for_decl (const_tree decl)
2136 {
2137 if (TREE_CODE (decl) == SSA_NAME)
2138 {
2139 /* We often try to use the SSA_NAME, instead of its underlying
2140 decl, to get type information and guide decisions, to avoid
2141 differences of behavior between anonymous and named
2142 variables, but in this one case we have to go for the actual
2143 variable if there is one. The main reason is that, at least
2144 at -O0, we want to place user variables on the stack, but we
2145 don't mind using pseudos for anonymous or ignored temps.
2146 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2147 should go in pseudos, whereas their corresponding variables
2148 might have to go on the stack. So, disregarding the decl
2149 here would negatively impact debug info at -O0, enable
2150 coalescing between SSA_NAMEs that ought to get different
2151 stack/pseudo assignments, and get the incoming argument
2152 processing thoroughly confused by PARM_DECLs expected to live
2153 in stack slots but assigned to pseudos. */
2154 if (!SSA_NAME_VAR (decl))
2155 return TYPE_MODE (TREE_TYPE (decl)) != BLKmode
2156 && !(flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)));
2157
2158 decl = SSA_NAME_VAR (decl);
2159 }
2160
2161 /* Honor volatile. */
2162 if (TREE_SIDE_EFFECTS (decl))
2163 return false;
2164
2165 /* Honor addressability. */
2166 if (TREE_ADDRESSABLE (decl))
2167 return false;
2168
2169 /* RESULT_DECLs are a bit special in that they're assigned without
2170 regard to use_register_for_decl, but we generally only store in
2171 them. If we coalesce their SSA NAMEs, we'd better return a
2172 result that matches the assignment in expand_function_start. */
2173 if (TREE_CODE (decl) == RESULT_DECL)
2174 {
2175 /* If it's not an aggregate, we're going to use a REG or a
2176 PARALLEL containing a REG. */
2177 if (!aggregate_value_p (decl, current_function_decl))
2178 return true;
2179
2180 /* If expand_function_start determines the return value, we'll
2181 use MEM if it's not by reference. */
2182 if (cfun->returns_pcc_struct
2183 || (targetm.calls.struct_value_rtx
2184 (TREE_TYPE (current_function_decl), 1)))
2185 return DECL_BY_REFERENCE (decl);
2186
2187 /* Otherwise, we're taking an extra all.function_result_decl
2188 argument. It's set up in assign_parms_augmented_arg_list,
2189 under the (negated) conditions above, and then it's used to
2190 set up the RESULT_DECL rtl in assign_params, after looping
2191 over all parameters. Now, if the RESULT_DECL is not by
2192 reference, we'll use a MEM either way. */
2193 if (!DECL_BY_REFERENCE (decl))
2194 return false;
2195
2196 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2197 the function_result_decl's assignment. Since it's a pointer,
2198 we can short-circuit a number of the tests below, and we must
2199 duplicat e them because we don't have the
2200 function_result_decl to test. */
2201 if (!targetm.calls.allocate_stack_slots_for_args ())
2202 return true;
2203 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2204 if (optimize)
2205 return true;
2206 /* We don't set DECL_REGISTER for the function_result_decl. */
2207 return false;
2208 }
2209
2210 /* Only register-like things go in registers. */
2211 if (DECL_MODE (decl) == BLKmode)
2212 return false;
2213
2214 /* If -ffloat-store specified, don't put explicit float variables
2215 into registers. */
2216 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2217 propagates values across these stores, and it probably shouldn't. */
2218 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2219 return false;
2220
2221 if (!targetm.calls.allocate_stack_slots_for_args ())
2222 return true;
2223
2224 /* If we're not interested in tracking debugging information for
2225 this decl, then we can certainly put it in a register. */
2226 if (DECL_IGNORED_P (decl))
2227 return true;
2228
2229 if (optimize)
2230 return true;
2231
2232 if (!DECL_REGISTER (decl))
2233 return false;
2234
2235 /* When not optimizing, disregard register keyword for types that
2236 could have methods, otherwise the methods won't be callable from
2237 the debugger. */
2238 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl)))
2239 return false;
2240
2241 return true;
2242 }
2243
2244 /* Structures to communicate between the subroutines of assign_parms.
2245 The first holds data persistent across all parameters, the second
2246 is cleared out for each parameter. */
2247
2248 struct assign_parm_data_all
2249 {
2250 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2251 should become a job of the target or otherwise encapsulated. */
2252 CUMULATIVE_ARGS args_so_far_v;
2253 cumulative_args_t args_so_far;
2254 struct args_size stack_args_size;
2255 tree function_result_decl;
2256 tree orig_fnargs;
2257 rtx_insn *first_conversion_insn;
2258 rtx_insn *last_conversion_insn;
2259 HOST_WIDE_INT pretend_args_size;
2260 HOST_WIDE_INT extra_pretend_bytes;
2261 int reg_parm_stack_space;
2262 };
2263
2264 struct assign_parm_data_one
2265 {
2266 tree nominal_type;
2267 tree passed_type;
2268 rtx entry_parm;
2269 rtx stack_parm;
2270 machine_mode nominal_mode;
2271 machine_mode passed_mode;
2272 machine_mode promoted_mode;
2273 struct locate_and_pad_arg_data locate;
2274 int partial;
2275 BOOL_BITFIELD named_arg : 1;
2276 BOOL_BITFIELD passed_pointer : 1;
2277 BOOL_BITFIELD on_stack : 1;
2278 BOOL_BITFIELD loaded_in_reg : 1;
2279 };
2280
2281 /* A subroutine of assign_parms. Initialize ALL. */
2282
2283 static void
2284 assign_parms_initialize_all (struct assign_parm_data_all *all)
2285 {
2286 tree fntype ATTRIBUTE_UNUSED;
2287
2288 memset (all, 0, sizeof (*all));
2289
2290 fntype = TREE_TYPE (current_function_decl);
2291
2292 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2293 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2294 #else
2295 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2296 current_function_decl, -1);
2297 #endif
2298 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2299
2300 #ifdef INCOMING_REG_PARM_STACK_SPACE
2301 all->reg_parm_stack_space
2302 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2303 #endif
2304 }
2305
2306 /* If ARGS contains entries with complex types, split the entry into two
2307 entries of the component type. Return a new list of substitutions are
2308 needed, else the old list. */
2309
2310 static void
2311 split_complex_args (vec<tree> *args)
2312 {
2313 unsigned i;
2314 tree p;
2315
2316 FOR_EACH_VEC_ELT (*args, i, p)
2317 {
2318 tree type = TREE_TYPE (p);
2319 if (TREE_CODE (type) == COMPLEX_TYPE
2320 && targetm.calls.split_complex_arg (type))
2321 {
2322 tree decl;
2323 tree subtype = TREE_TYPE (type);
2324 bool addressable = TREE_ADDRESSABLE (p);
2325
2326 /* Rewrite the PARM_DECL's type with its component. */
2327 p = copy_node (p);
2328 TREE_TYPE (p) = subtype;
2329 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2330 SET_DECL_MODE (p, VOIDmode);
2331 DECL_SIZE (p) = NULL;
2332 DECL_SIZE_UNIT (p) = NULL;
2333 /* If this arg must go in memory, put it in a pseudo here.
2334 We can't allow it to go in memory as per normal parms,
2335 because the usual place might not have the imag part
2336 adjacent to the real part. */
2337 DECL_ARTIFICIAL (p) = addressable;
2338 DECL_IGNORED_P (p) = addressable;
2339 TREE_ADDRESSABLE (p) = 0;
2340 layout_decl (p, 0);
2341 (*args)[i] = p;
2342
2343 /* Build a second synthetic decl. */
2344 decl = build_decl (EXPR_LOCATION (p),
2345 PARM_DECL, NULL_TREE, subtype);
2346 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2347 DECL_ARTIFICIAL (decl) = addressable;
2348 DECL_IGNORED_P (decl) = addressable;
2349 layout_decl (decl, 0);
2350 args->safe_insert (++i, decl);
2351 }
2352 }
2353 }
2354
2355 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2356 the hidden struct return argument, and (abi willing) complex args.
2357 Return the new parameter list. */
2358
2359 static vec<tree>
2360 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2361 {
2362 tree fndecl = current_function_decl;
2363 tree fntype = TREE_TYPE (fndecl);
2364 vec<tree> fnargs = vNULL;
2365 tree arg;
2366
2367 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2368 fnargs.safe_push (arg);
2369
2370 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2371
2372 /* If struct value address is treated as the first argument, make it so. */
2373 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2374 && ! cfun->returns_pcc_struct
2375 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2376 {
2377 tree type = build_pointer_type (TREE_TYPE (fntype));
2378 tree decl;
2379
2380 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2381 PARM_DECL, get_identifier (".result_ptr"), type);
2382 DECL_ARG_TYPE (decl) = type;
2383 DECL_ARTIFICIAL (decl) = 1;
2384 DECL_NAMELESS (decl) = 1;
2385 TREE_CONSTANT (decl) = 1;
2386 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2387 changes, the end of the RESULT_DECL handling block in
2388 use_register_for_decl must be adjusted to match. */
2389
2390 DECL_CHAIN (decl) = all->orig_fnargs;
2391 all->orig_fnargs = decl;
2392 fnargs.safe_insert (0, decl);
2393
2394 all->function_result_decl = decl;
2395 }
2396
2397 /* If the target wants to split complex arguments into scalars, do so. */
2398 if (targetm.calls.split_complex_arg)
2399 split_complex_args (&fnargs);
2400
2401 return fnargs;
2402 }
2403
2404 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2405 data for the parameter. Incorporate ABI specifics such as pass-by-
2406 reference and type promotion. */
2407
2408 static void
2409 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2410 struct assign_parm_data_one *data)
2411 {
2412 tree nominal_type, passed_type;
2413 machine_mode nominal_mode, passed_mode, promoted_mode;
2414 int unsignedp;
2415
2416 memset (data, 0, sizeof (*data));
2417
2418 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2419 if (!cfun->stdarg)
2420 data->named_arg = 1; /* No variadic parms. */
2421 else if (DECL_CHAIN (parm))
2422 data->named_arg = 1; /* Not the last non-variadic parm. */
2423 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2424 data->named_arg = 1; /* Only variadic ones are unnamed. */
2425 else
2426 data->named_arg = 0; /* Treat as variadic. */
2427
2428 nominal_type = TREE_TYPE (parm);
2429 passed_type = DECL_ARG_TYPE (parm);
2430
2431 /* Look out for errors propagating this far. Also, if the parameter's
2432 type is void then its value doesn't matter. */
2433 if (TREE_TYPE (parm) == error_mark_node
2434 /* This can happen after weird syntax errors
2435 or if an enum type is defined among the parms. */
2436 || TREE_CODE (parm) != PARM_DECL
2437 || passed_type == NULL
2438 || VOID_TYPE_P (nominal_type))
2439 {
2440 nominal_type = passed_type = void_type_node;
2441 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2442 goto egress;
2443 }
2444
2445 /* Find mode of arg as it is passed, and mode of arg as it should be
2446 during execution of this function. */
2447 passed_mode = TYPE_MODE (passed_type);
2448 nominal_mode = TYPE_MODE (nominal_type);
2449
2450 /* If the parm is to be passed as a transparent union or record, use the
2451 type of the first field for the tests below. We have already verified
2452 that the modes are the same. */
2453 if ((TREE_CODE (passed_type) == UNION_TYPE
2454 || TREE_CODE (passed_type) == RECORD_TYPE)
2455 && TYPE_TRANSPARENT_AGGR (passed_type))
2456 passed_type = TREE_TYPE (first_field (passed_type));
2457
2458 /* See if this arg was passed by invisible reference. */
2459 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2460 passed_type, data->named_arg))
2461 {
2462 passed_type = nominal_type = build_pointer_type (passed_type);
2463 data->passed_pointer = true;
2464 passed_mode = nominal_mode = TYPE_MODE (nominal_type);
2465 }
2466
2467 /* Find mode as it is passed by the ABI. */
2468 unsignedp = TYPE_UNSIGNED (passed_type);
2469 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2470 TREE_TYPE (current_function_decl), 0);
2471
2472 egress:
2473 data->nominal_type = nominal_type;
2474 data->passed_type = passed_type;
2475 data->nominal_mode = nominal_mode;
2476 data->passed_mode = passed_mode;
2477 data->promoted_mode = promoted_mode;
2478 }
2479
2480 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2481
2482 static void
2483 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2484 struct assign_parm_data_one *data, bool no_rtl)
2485 {
2486 int varargs_pretend_bytes = 0;
2487
2488 targetm.calls.setup_incoming_varargs (all->args_so_far,
2489 data->promoted_mode,
2490 data->passed_type,
2491 &varargs_pretend_bytes, no_rtl);
2492
2493 /* If the back-end has requested extra stack space, record how much is
2494 needed. Do not change pretend_args_size otherwise since it may be
2495 nonzero from an earlier partial argument. */
2496 if (varargs_pretend_bytes > 0)
2497 all->pretend_args_size = varargs_pretend_bytes;
2498 }
2499
2500 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2501 the incoming location of the current parameter. */
2502
2503 static void
2504 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2505 struct assign_parm_data_one *data)
2506 {
2507 HOST_WIDE_INT pretend_bytes = 0;
2508 rtx entry_parm;
2509 bool in_regs;
2510
2511 if (data->promoted_mode == VOIDmode)
2512 {
2513 data->entry_parm = data->stack_parm = const0_rtx;
2514 return;
2515 }
2516
2517 targetm.calls.warn_parameter_passing_abi (all->args_so_far,
2518 data->passed_type);
2519
2520 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2521 data->promoted_mode,
2522 data->passed_type,
2523 data->named_arg);
2524
2525 if (entry_parm == 0)
2526 data->promoted_mode = data->passed_mode;
2527
2528 /* Determine parm's home in the stack, in case it arrives in the stack
2529 or we should pretend it did. Compute the stack position and rtx where
2530 the argument arrives and its size.
2531
2532 There is one complexity here: If this was a parameter that would
2533 have been passed in registers, but wasn't only because it is
2534 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2535 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2536 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2537 as it was the previous time. */
2538 in_regs = (entry_parm != 0);
2539 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2540 in_regs = true;
2541 #endif
2542 if (!in_regs && !data->named_arg)
2543 {
2544 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2545 {
2546 rtx tem;
2547 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2548 data->promoted_mode,
2549 data->passed_type, true);
2550 in_regs = tem != NULL;
2551 }
2552 }
2553
2554 /* If this parameter was passed both in registers and in the stack, use
2555 the copy on the stack. */
2556 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2557 data->passed_type))
2558 entry_parm = 0;
2559
2560 if (entry_parm)
2561 {
2562 int partial;
2563
2564 partial = targetm.calls.arg_partial_bytes (all->args_so_far,
2565 data->promoted_mode,
2566 data->passed_type,
2567 data->named_arg);
2568 data->partial = partial;
2569
2570 /* The caller might already have allocated stack space for the
2571 register parameters. */
2572 if (partial != 0 && all->reg_parm_stack_space == 0)
2573 {
2574 /* Part of this argument is passed in registers and part
2575 is passed on the stack. Ask the prologue code to extend
2576 the stack part so that we can recreate the full value.
2577
2578 PRETEND_BYTES is the size of the registers we need to store.
2579 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2580 stack space that the prologue should allocate.
2581
2582 Internally, gcc assumes that the argument pointer is aligned
2583 to STACK_BOUNDARY bits. This is used both for alignment
2584 optimizations (see init_emit) and to locate arguments that are
2585 aligned to more than PARM_BOUNDARY bits. We must preserve this
2586 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2587 a stack boundary. */
2588
2589 /* We assume at most one partial arg, and it must be the first
2590 argument on the stack. */
2591 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2592
2593 pretend_bytes = partial;
2594 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2595
2596 /* We want to align relative to the actual stack pointer, so
2597 don't include this in the stack size until later. */
2598 all->extra_pretend_bytes = all->pretend_args_size;
2599 }
2600 }
2601
2602 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2603 all->reg_parm_stack_space,
2604 entry_parm ? data->partial : 0, current_function_decl,
2605 &all->stack_args_size, &data->locate);
2606
2607 /* Update parm_stack_boundary if this parameter is passed in the
2608 stack. */
2609 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2610 crtl->parm_stack_boundary = data->locate.boundary;
2611
2612 /* Adjust offsets to include the pretend args. */
2613 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2614 data->locate.slot_offset.constant += pretend_bytes;
2615 data->locate.offset.constant += pretend_bytes;
2616
2617 data->entry_parm = entry_parm;
2618 }
2619
2620 /* A subroutine of assign_parms. If there is actually space on the stack
2621 for this parm, count it in stack_args_size and return true. */
2622
2623 static bool
2624 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2625 struct assign_parm_data_one *data)
2626 {
2627 /* Trivially true if we've no incoming register. */
2628 if (data->entry_parm == NULL)
2629 ;
2630 /* Also true if we're partially in registers and partially not,
2631 since we've arranged to drop the entire argument on the stack. */
2632 else if (data->partial != 0)
2633 ;
2634 /* Also true if the target says that it's passed in both registers
2635 and on the stack. */
2636 else if (GET_CODE (data->entry_parm) == PARALLEL
2637 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2638 ;
2639 /* Also true if the target says that there's stack allocated for
2640 all register parameters. */
2641 else if (all->reg_parm_stack_space > 0)
2642 ;
2643 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2644 else
2645 return false;
2646
2647 all->stack_args_size.constant += data->locate.size.constant;
2648 if (data->locate.size.var)
2649 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2650
2651 return true;
2652 }
2653
2654 /* A subroutine of assign_parms. Given that this parameter is allocated
2655 stack space by the ABI, find it. */
2656
2657 static void
2658 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2659 {
2660 rtx offset_rtx, stack_parm;
2661 unsigned int align, boundary;
2662
2663 /* If we're passing this arg using a reg, make its stack home the
2664 aligned stack slot. */
2665 if (data->entry_parm)
2666 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2667 else
2668 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2669
2670 stack_parm = crtl->args.internal_arg_pointer;
2671 if (offset_rtx != const0_rtx)
2672 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2673 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2674
2675 if (!data->passed_pointer)
2676 {
2677 set_mem_attributes (stack_parm, parm, 1);
2678 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2679 while promoted mode's size is needed. */
2680 if (data->promoted_mode != BLKmode
2681 && data->promoted_mode != DECL_MODE (parm))
2682 {
2683 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2684 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2685 {
2686 poly_int64 offset = subreg_lowpart_offset (DECL_MODE (parm),
2687 data->promoted_mode);
2688 if (maybe_ne (offset, 0))
2689 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2690 }
2691 }
2692 }
2693
2694 boundary = data->locate.boundary;
2695 align = BITS_PER_UNIT;
2696
2697 /* If we're padding upward, we know that the alignment of the slot
2698 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2699 intentionally forcing upward padding. Otherwise we have to come
2700 up with a guess at the alignment based on OFFSET_RTX. */
2701 poly_int64 offset;
2702 if (data->locate.where_pad != PAD_DOWNWARD || data->entry_parm)
2703 align = boundary;
2704 else if (poly_int_rtx_p (offset_rtx, &offset))
2705 {
2706 align = least_bit_hwi (boundary);
2707 unsigned int offset_align = known_alignment (offset) * BITS_PER_UNIT;
2708 if (offset_align != 0)
2709 align = MIN (align, offset_align);
2710 }
2711 set_mem_align (stack_parm, align);
2712
2713 if (data->entry_parm)
2714 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2715
2716 data->stack_parm = stack_parm;
2717 }
2718
2719 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2720 always valid and contiguous. */
2721
2722 static void
2723 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2724 {
2725 rtx entry_parm = data->entry_parm;
2726 rtx stack_parm = data->stack_parm;
2727
2728 /* If this parm was passed part in regs and part in memory, pretend it
2729 arrived entirely in memory by pushing the register-part onto the stack.
2730 In the special case of a DImode or DFmode that is split, we could put
2731 it together in a pseudoreg directly, but for now that's not worth
2732 bothering with. */
2733 if (data->partial != 0)
2734 {
2735 /* Handle calls that pass values in multiple non-contiguous
2736 locations. The Irix 6 ABI has examples of this. */
2737 if (GET_CODE (entry_parm) == PARALLEL)
2738 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2739 data->passed_type,
2740 int_size_in_bytes (data->passed_type));
2741 else
2742 {
2743 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2744 move_block_from_reg (REGNO (entry_parm),
2745 validize_mem (copy_rtx (stack_parm)),
2746 data->partial / UNITS_PER_WORD);
2747 }
2748
2749 entry_parm = stack_parm;
2750 }
2751
2752 /* If we didn't decide this parm came in a register, by default it came
2753 on the stack. */
2754 else if (entry_parm == NULL)
2755 entry_parm = stack_parm;
2756
2757 /* When an argument is passed in multiple locations, we can't make use
2758 of this information, but we can save some copying if the whole argument
2759 is passed in a single register. */
2760 else if (GET_CODE (entry_parm) == PARALLEL
2761 && data->nominal_mode != BLKmode
2762 && data->passed_mode != BLKmode)
2763 {
2764 size_t i, len = XVECLEN (entry_parm, 0);
2765
2766 for (i = 0; i < len; i++)
2767 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2768 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2769 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2770 == data->passed_mode)
2771 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2772 {
2773 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2774 break;
2775 }
2776 }
2777
2778 data->entry_parm = entry_parm;
2779 }
2780
2781 /* A subroutine of assign_parms. Reconstitute any values which were
2782 passed in multiple registers and would fit in a single register. */
2783
2784 static void
2785 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2786 {
2787 rtx entry_parm = data->entry_parm;
2788
2789 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2790 This can be done with register operations rather than on the
2791 stack, even if we will store the reconstituted parameter on the
2792 stack later. */
2793 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2794 {
2795 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2796 emit_group_store (parmreg, entry_parm, data->passed_type,
2797 GET_MODE_SIZE (GET_MODE (entry_parm)));
2798 entry_parm = parmreg;
2799 }
2800
2801 data->entry_parm = entry_parm;
2802 }
2803
2804 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2805 always valid and properly aligned. */
2806
2807 static void
2808 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2809 {
2810 rtx stack_parm = data->stack_parm;
2811
2812 /* If we can't trust the parm stack slot to be aligned enough for its
2813 ultimate type, don't use that slot after entry. We'll make another
2814 stack slot, if we need one. */
2815 if (stack_parm
2816 && ((STRICT_ALIGNMENT
2817 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2818 || (data->nominal_type
2819 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2820 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2821 stack_parm = NULL;
2822
2823 /* If parm was passed in memory, and we need to convert it on entry,
2824 don't store it back in that same slot. */
2825 else if (data->entry_parm == stack_parm
2826 && data->nominal_mode != BLKmode
2827 && data->nominal_mode != data->passed_mode)
2828 stack_parm = NULL;
2829
2830 /* If stack protection is in effect for this function, don't leave any
2831 pointers in their passed stack slots. */
2832 else if (crtl->stack_protect_guard
2833 && (flag_stack_protect == 2
2834 || data->passed_pointer
2835 || POINTER_TYPE_P (data->nominal_type)))
2836 stack_parm = NULL;
2837
2838 data->stack_parm = stack_parm;
2839 }
2840
2841 /* A subroutine of assign_parms. Return true if the current parameter
2842 should be stored as a BLKmode in the current frame. */
2843
2844 static bool
2845 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2846 {
2847 if (data->nominal_mode == BLKmode)
2848 return true;
2849 if (GET_MODE (data->entry_parm) == BLKmode)
2850 return true;
2851
2852 #ifdef BLOCK_REG_PADDING
2853 /* Only assign_parm_setup_block knows how to deal with register arguments
2854 that are padded at the least significant end. */
2855 if (REG_P (data->entry_parm)
2856 && known_lt (GET_MODE_SIZE (data->promoted_mode), UNITS_PER_WORD)
2857 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2858 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2859 return true;
2860 #endif
2861
2862 return false;
2863 }
2864
2865 /* A subroutine of assign_parms. Arrange for the parameter to be
2866 present and valid in DATA->STACK_RTL. */
2867
2868 static void
2869 assign_parm_setup_block (struct assign_parm_data_all *all,
2870 tree parm, struct assign_parm_data_one *data)
2871 {
2872 rtx entry_parm = data->entry_parm;
2873 rtx stack_parm = data->stack_parm;
2874 rtx target_reg = NULL_RTX;
2875 bool in_conversion_seq = false;
2876 HOST_WIDE_INT size;
2877 HOST_WIDE_INT size_stored;
2878
2879 if (GET_CODE (entry_parm) == PARALLEL)
2880 entry_parm = emit_group_move_into_temps (entry_parm);
2881
2882 /* If we want the parameter in a pseudo, don't use a stack slot. */
2883 if (is_gimple_reg (parm) && use_register_for_decl (parm))
2884 {
2885 tree def = ssa_default_def (cfun, parm);
2886 gcc_assert (def);
2887 machine_mode mode = promote_ssa_mode (def, NULL);
2888 rtx reg = gen_reg_rtx (mode);
2889 if (GET_CODE (reg) != CONCAT)
2890 stack_parm = reg;
2891 else
2892 {
2893 target_reg = reg;
2894 /* Avoid allocating a stack slot, if there isn't one
2895 preallocated by the ABI. It might seem like we should
2896 always prefer a pseudo, but converting between
2897 floating-point and integer modes goes through the stack
2898 on various machines, so it's better to use the reserved
2899 stack slot than to risk wasting it and allocating more
2900 for the conversion. */
2901 if (stack_parm == NULL_RTX)
2902 {
2903 int save = generating_concat_p;
2904 generating_concat_p = 0;
2905 stack_parm = gen_reg_rtx (mode);
2906 generating_concat_p = save;
2907 }
2908 }
2909 data->stack_parm = NULL;
2910 }
2911
2912 size = int_size_in_bytes (data->passed_type);
2913 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2914 if (stack_parm == 0)
2915 {
2916 HOST_WIDE_INT parm_align
2917 = (STRICT_ALIGNMENT
2918 ? MAX (DECL_ALIGN (parm), BITS_PER_WORD) : DECL_ALIGN (parm));
2919
2920 SET_DECL_ALIGN (parm, parm_align);
2921 if (DECL_ALIGN (parm) > MAX_SUPPORTED_STACK_ALIGNMENT)
2922 {
2923 rtx allocsize = gen_int_mode (size_stored, Pmode);
2924 get_dynamic_stack_size (&allocsize, 0, DECL_ALIGN (parm), NULL);
2925 stack_parm = assign_stack_local (BLKmode, UINTVAL (allocsize),
2926 MAX_SUPPORTED_STACK_ALIGNMENT);
2927 rtx addr = align_dynamic_address (XEXP (stack_parm, 0),
2928 DECL_ALIGN (parm));
2929 mark_reg_pointer (addr, DECL_ALIGN (parm));
2930 stack_parm = gen_rtx_MEM (GET_MODE (stack_parm), addr);
2931 MEM_NOTRAP_P (stack_parm) = 1;
2932 }
2933 else
2934 stack_parm = assign_stack_local (BLKmode, size_stored,
2935 DECL_ALIGN (parm));
2936 if (known_eq (GET_MODE_SIZE (GET_MODE (entry_parm)), size))
2937 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2938 set_mem_attributes (stack_parm, parm, 1);
2939 }
2940
2941 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2942 calls that pass values in multiple non-contiguous locations. */
2943 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2944 {
2945 rtx mem;
2946
2947 /* Note that we will be storing an integral number of words.
2948 So we have to be careful to ensure that we allocate an
2949 integral number of words. We do this above when we call
2950 assign_stack_local if space was not allocated in the argument
2951 list. If it was, this will not work if PARM_BOUNDARY is not
2952 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2953 if it becomes a problem. Exception is when BLKmode arrives
2954 with arguments not conforming to word_mode. */
2955
2956 if (data->stack_parm == 0)
2957 ;
2958 else if (GET_CODE (entry_parm) == PARALLEL)
2959 ;
2960 else
2961 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2962
2963 mem = validize_mem (copy_rtx (stack_parm));
2964
2965 /* Handle values in multiple non-contiguous locations. */
2966 if (GET_CODE (entry_parm) == PARALLEL && !MEM_P (mem))
2967 emit_group_store (mem, entry_parm, data->passed_type, size);
2968 else if (GET_CODE (entry_parm) == PARALLEL)
2969 {
2970 push_to_sequence2 (all->first_conversion_insn,
2971 all->last_conversion_insn);
2972 emit_group_store (mem, entry_parm, data->passed_type, size);
2973 all->first_conversion_insn = get_insns ();
2974 all->last_conversion_insn = get_last_insn ();
2975 end_sequence ();
2976 in_conversion_seq = true;
2977 }
2978
2979 else if (size == 0)
2980 ;
2981
2982 /* If SIZE is that of a mode no bigger than a word, just use
2983 that mode's store operation. */
2984 else if (size <= UNITS_PER_WORD)
2985 {
2986 unsigned int bits = size * BITS_PER_UNIT;
2987 machine_mode mode = int_mode_for_size (bits, 0).else_blk ();
2988
2989 if (mode != BLKmode
2990 #ifdef BLOCK_REG_PADDING
2991 && (size == UNITS_PER_WORD
2992 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2993 != (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2994 #endif
2995 )
2996 {
2997 rtx reg;
2998
2999 /* We are really truncating a word_mode value containing
3000 SIZE bytes into a value of mode MODE. If such an
3001 operation requires no actual instructions, we can refer
3002 to the value directly in mode MODE, otherwise we must
3003 start with the register in word_mode and explicitly
3004 convert it. */
3005 if (targetm.truly_noop_truncation (size * BITS_PER_UNIT,
3006 BITS_PER_WORD))
3007 reg = gen_rtx_REG (mode, REGNO (entry_parm));
3008 else
3009 {
3010 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3011 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
3012 }
3013 emit_move_insn (change_address (mem, mode, 0), reg);
3014 }
3015
3016 #ifdef BLOCK_REG_PADDING
3017 /* Storing the register in memory as a full word, as
3018 move_block_from_reg below would do, and then using the
3019 MEM in a smaller mode, has the effect of shifting right
3020 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3021 shifting must be explicit. */
3022 else if (!MEM_P (mem))
3023 {
3024 rtx x;
3025
3026 /* If the assert below fails, we should have taken the
3027 mode != BLKmode path above, unless we have downward
3028 padding of smaller-than-word arguments on a machine
3029 with little-endian bytes, which would likely require
3030 additional changes to work correctly. */
3031 gcc_checking_assert (BYTES_BIG_ENDIAN
3032 && (BLOCK_REG_PADDING (mode,
3033 data->passed_type, 1)
3034 == PAD_UPWARD));
3035
3036 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3037
3038 x = gen_rtx_REG (word_mode, REGNO (entry_parm));
3039 x = expand_shift (RSHIFT_EXPR, word_mode, x, by,
3040 NULL_RTX, 1);
3041 x = force_reg (word_mode, x);
3042 x = gen_lowpart_SUBREG (GET_MODE (mem), x);
3043
3044 emit_move_insn (mem, x);
3045 }
3046 #endif
3047
3048 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3049 machine must be aligned to the left before storing
3050 to memory. Note that the previous test doesn't
3051 handle all cases (e.g. SIZE == 3). */
3052 else if (size != UNITS_PER_WORD
3053 #ifdef BLOCK_REG_PADDING
3054 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
3055 == PAD_DOWNWARD)
3056 #else
3057 && BYTES_BIG_ENDIAN
3058 #endif
3059 )
3060 {
3061 rtx tem, x;
3062 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3063 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3064
3065 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
3066 tem = change_address (mem, word_mode, 0);
3067 emit_move_insn (tem, x);
3068 }
3069 else
3070 move_block_from_reg (REGNO (entry_parm), mem,
3071 size_stored / UNITS_PER_WORD);
3072 }
3073 else if (!MEM_P (mem))
3074 {
3075 gcc_checking_assert (size > UNITS_PER_WORD);
3076 #ifdef BLOCK_REG_PADDING
3077 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem),
3078 data->passed_type, 0)
3079 == PAD_UPWARD);
3080 #endif
3081 emit_move_insn (mem, entry_parm);
3082 }
3083 else
3084 move_block_from_reg (REGNO (entry_parm), mem,
3085 size_stored / UNITS_PER_WORD);
3086 }
3087 else if (data->stack_parm == 0)
3088 {
3089 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3090 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
3091 BLOCK_OP_NORMAL);
3092 all->first_conversion_insn = get_insns ();
3093 all->last_conversion_insn = get_last_insn ();
3094 end_sequence ();
3095 in_conversion_seq = true;
3096 }
3097
3098 if (target_reg)
3099 {
3100 if (!in_conversion_seq)
3101 emit_move_insn (target_reg, stack_parm);
3102 else
3103 {
3104 push_to_sequence2 (all->first_conversion_insn,
3105 all->last_conversion_insn);
3106 emit_move_insn (target_reg, stack_parm);
3107 all->first_conversion_insn = get_insns ();
3108 all->last_conversion_insn = get_last_insn ();
3109 end_sequence ();
3110 }
3111 stack_parm = target_reg;
3112 }
3113
3114 data->stack_parm = stack_parm;
3115 set_parm_rtl (parm, stack_parm);
3116 }
3117
3118 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3119 parameter. Get it there. Perform all ABI specified conversions. */
3120
3121 static void
3122 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
3123 struct assign_parm_data_one *data)
3124 {
3125 rtx parmreg, validated_mem;
3126 rtx equiv_stack_parm;
3127 machine_mode promoted_nominal_mode;
3128 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
3129 bool did_conversion = false;
3130 bool need_conversion, moved;
3131 rtx rtl;
3132
3133 /* Store the parm in a pseudoregister during the function, but we may
3134 need to do it in a wider mode. Using 2 here makes the result
3135 consistent with promote_decl_mode and thus expand_expr_real_1. */
3136 promoted_nominal_mode
3137 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
3138 TREE_TYPE (current_function_decl), 2);
3139
3140 parmreg = gen_reg_rtx (promoted_nominal_mode);
3141 if (!DECL_ARTIFICIAL (parm))
3142 mark_user_reg (parmreg);
3143
3144 /* If this was an item that we received a pointer to,
3145 set rtl appropriately. */
3146 if (data->passed_pointer)
3147 {
3148 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
3149 set_mem_attributes (rtl, parm, 1);
3150 }
3151 else
3152 rtl = parmreg;
3153
3154 assign_parm_remove_parallels (data);
3155
3156 /* Copy the value into the register, thus bridging between
3157 assign_parm_find_data_types and expand_expr_real_1. */
3158
3159 equiv_stack_parm = data->stack_parm;
3160 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3161
3162 need_conversion = (data->nominal_mode != data->passed_mode
3163 || promoted_nominal_mode != data->promoted_mode);
3164 moved = false;
3165
3166 if (need_conversion
3167 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3168 && data->nominal_mode == data->passed_mode
3169 && data->nominal_mode == GET_MODE (data->entry_parm))
3170 {
3171 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3172 mode, by the caller. We now have to convert it to
3173 NOMINAL_MODE, if different. However, PARMREG may be in
3174 a different mode than NOMINAL_MODE if it is being stored
3175 promoted.
3176
3177 If ENTRY_PARM is a hard register, it might be in a register
3178 not valid for operating in its mode (e.g., an odd-numbered
3179 register for a DFmode). In that case, moves are the only
3180 thing valid, so we can't do a convert from there. This
3181 occurs when the calling sequence allow such misaligned
3182 usages.
3183
3184 In addition, the conversion may involve a call, which could
3185 clobber parameters which haven't been copied to pseudo
3186 registers yet.
3187
3188 First, we try to emit an insn which performs the necessary
3189 conversion. We verify that this insn does not clobber any
3190 hard registers. */
3191
3192 enum insn_code icode;
3193 rtx op0, op1;
3194
3195 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3196 unsignedp);
3197
3198 op0 = parmreg;
3199 op1 = validated_mem;
3200 if (icode != CODE_FOR_nothing
3201 && insn_operand_matches (icode, 0, op0)
3202 && insn_operand_matches (icode, 1, op1))
3203 {
3204 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3205 rtx_insn *insn, *insns;
3206 rtx t = op1;
3207 HARD_REG_SET hardregs;
3208
3209 start_sequence ();
3210 /* If op1 is a hard register that is likely spilled, first
3211 force it into a pseudo, otherwise combiner might extend
3212 its lifetime too much. */
3213 if (GET_CODE (t) == SUBREG)
3214 t = SUBREG_REG (t);
3215 if (REG_P (t)
3216 && HARD_REGISTER_P (t)
3217 && ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
3218 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
3219 {
3220 t = gen_reg_rtx (GET_MODE (op1));
3221 emit_move_insn (t, op1);
3222 }
3223 else
3224 t = op1;
3225 rtx_insn *pat = gen_extend_insn (op0, t, promoted_nominal_mode,
3226 data->passed_mode, unsignedp);
3227 emit_insn (pat);
3228 insns = get_insns ();
3229
3230 moved = true;
3231 CLEAR_HARD_REG_SET (hardregs);
3232 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3233 {
3234 if (INSN_P (insn))
3235 note_stores (PATTERN (insn), record_hard_reg_sets,
3236 &hardregs);
3237 if (!hard_reg_set_empty_p (hardregs))
3238 moved = false;
3239 }
3240
3241 end_sequence ();
3242
3243 if (moved)
3244 {
3245 emit_insn (insns);
3246 if (equiv_stack_parm != NULL_RTX)
3247 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3248 equiv_stack_parm);
3249 }
3250 }
3251 }
3252
3253 if (moved)
3254 /* Nothing to do. */
3255 ;
3256 else if (need_conversion)
3257 {
3258 /* We did not have an insn to convert directly, or the sequence
3259 generated appeared unsafe. We must first copy the parm to a
3260 pseudo reg, and save the conversion until after all
3261 parameters have been moved. */
3262
3263 int save_tree_used;
3264 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3265
3266 emit_move_insn (tempreg, validated_mem);
3267
3268 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3269 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3270
3271 if (partial_subreg_p (tempreg)
3272 && GET_MODE (tempreg) == data->nominal_mode
3273 && REG_P (SUBREG_REG (tempreg))
3274 && data->nominal_mode == data->passed_mode
3275 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm))
3276 {
3277 /* The argument is already sign/zero extended, so note it
3278 into the subreg. */
3279 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3280 SUBREG_PROMOTED_SET (tempreg, unsignedp);
3281 }
3282
3283 /* TREE_USED gets set erroneously during expand_assignment. */
3284 save_tree_used = TREE_USED (parm);
3285 SET_DECL_RTL (parm, rtl);
3286 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3287 SET_DECL_RTL (parm, NULL_RTX);
3288 TREE_USED (parm) = save_tree_used;
3289 all->first_conversion_insn = get_insns ();
3290 all->last_conversion_insn = get_last_insn ();
3291 end_sequence ();
3292
3293 did_conversion = true;
3294 }
3295 else
3296 emit_move_insn (parmreg, validated_mem);
3297
3298 /* If we were passed a pointer but the actual value can safely live
3299 in a register, retrieve it and use it directly. */
3300 if (data->passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3301 {
3302 /* We can't use nominal_mode, because it will have been set to
3303 Pmode above. We must use the actual mode of the parm. */
3304 if (use_register_for_decl (parm))
3305 {
3306 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3307 mark_user_reg (parmreg);
3308 }
3309 else
3310 {
3311 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3312 TYPE_MODE (TREE_TYPE (parm)),
3313 TYPE_ALIGN (TREE_TYPE (parm)));
3314 parmreg
3315 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3316 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3317 align);
3318 set_mem_attributes (parmreg, parm, 1);
3319 }
3320
3321 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3322 the debug info in case it is not legitimate. */
3323 if (GET_MODE (parmreg) != GET_MODE (rtl))
3324 {
3325 rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
3326 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3327
3328 push_to_sequence2 (all->first_conversion_insn,
3329 all->last_conversion_insn);
3330 emit_move_insn (tempreg, rtl);
3331 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3332 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
3333 tempreg);
3334 all->first_conversion_insn = get_insns ();
3335 all->last_conversion_insn = get_last_insn ();
3336 end_sequence ();
3337
3338 did_conversion = true;
3339 }
3340 else
3341 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
3342
3343 rtl = parmreg;
3344
3345 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3346 now the parm. */
3347 data->stack_parm = NULL;
3348 }
3349
3350 set_parm_rtl (parm, rtl);
3351
3352 /* Mark the register as eliminable if we did no conversion and it was
3353 copied from memory at a fixed offset, and the arg pointer was not
3354 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3355 offset formed an invalid address, such memory-equivalences as we
3356 make here would screw up life analysis for it. */
3357 if (data->nominal_mode == data->passed_mode
3358 && !did_conversion
3359 && data->stack_parm != 0
3360 && MEM_P (data->stack_parm)
3361 && data->locate.offset.var == 0
3362 && reg_mentioned_p (virtual_incoming_args_rtx,
3363 XEXP (data->stack_parm, 0)))
3364 {
3365 rtx_insn *linsn = get_last_insn ();
3366 rtx_insn *sinsn;
3367 rtx set;
3368
3369 /* Mark complex types separately. */
3370 if (GET_CODE (parmreg) == CONCAT)
3371 {
3372 scalar_mode submode = GET_MODE_INNER (GET_MODE (parmreg));
3373 int regnor = REGNO (XEXP (parmreg, 0));
3374 int regnoi = REGNO (XEXP (parmreg, 1));
3375 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3376 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3377 GET_MODE_SIZE (submode));
3378
3379 /* Scan backwards for the set of the real and
3380 imaginary parts. */
3381 for (sinsn = linsn; sinsn != 0;
3382 sinsn = prev_nonnote_insn (sinsn))
3383 {
3384 set = single_set (sinsn);
3385 if (set == 0)
3386 continue;
3387
3388 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3389 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3390 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3391 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3392 }
3393 }
3394 else
3395 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3396 }
3397
3398 /* For pointer data type, suggest pointer register. */
3399 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3400 mark_reg_pointer (parmreg,
3401 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3402 }
3403
3404 /* A subroutine of assign_parms. Allocate stack space to hold the current
3405 parameter. Get it there. Perform all ABI specified conversions. */
3406
3407 static void
3408 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3409 struct assign_parm_data_one *data)
3410 {
3411 /* Value must be stored in the stack slot STACK_PARM during function
3412 execution. */
3413 bool to_conversion = false;
3414
3415 assign_parm_remove_parallels (data);
3416
3417 if (data->promoted_mode != data->nominal_mode)
3418 {
3419 /* Conversion is required. */
3420 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3421
3422 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3423
3424 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3425 to_conversion = true;
3426
3427 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3428 TYPE_UNSIGNED (TREE_TYPE (parm)));
3429
3430 if (data->stack_parm)
3431 {
3432 poly_int64 offset
3433 = subreg_lowpart_offset (data->nominal_mode,
3434 GET_MODE (data->stack_parm));
3435 /* ??? This may need a big-endian conversion on sparc64. */
3436 data->stack_parm
3437 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3438 if (maybe_ne (offset, 0) && MEM_OFFSET_KNOWN_P (data->stack_parm))
3439 set_mem_offset (data->stack_parm,
3440 MEM_OFFSET (data->stack_parm) + offset);
3441 }
3442 }
3443
3444 if (data->entry_parm != data->stack_parm)
3445 {
3446 rtx src, dest;
3447
3448 if (data->stack_parm == 0)
3449 {
3450 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3451 GET_MODE (data->entry_parm),
3452 TYPE_ALIGN (data->passed_type));
3453 data->stack_parm
3454 = assign_stack_local (GET_MODE (data->entry_parm),
3455 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3456 align);
3457 set_mem_attributes (data->stack_parm, parm, 1);
3458 }
3459
3460 dest = validize_mem (copy_rtx (data->stack_parm));
3461 src = validize_mem (copy_rtx (data->entry_parm));
3462
3463 if (MEM_P (src))
3464 {
3465 /* Use a block move to handle potentially misaligned entry_parm. */
3466 if (!to_conversion)
3467 push_to_sequence2 (all->first_conversion_insn,
3468 all->last_conversion_insn);
3469 to_conversion = true;
3470
3471 emit_block_move (dest, src,
3472 GEN_INT (int_size_in_bytes (data->passed_type)),
3473 BLOCK_OP_NORMAL);
3474 }
3475 else
3476 {
3477 if (!REG_P (src))
3478 src = force_reg (GET_MODE (src), src);
3479 emit_move_insn (dest, src);
3480 }
3481 }
3482
3483 if (to_conversion)
3484 {
3485 all->first_conversion_insn = get_insns ();
3486 all->last_conversion_insn = get_last_insn ();
3487 end_sequence ();
3488 }
3489
3490 set_parm_rtl (parm, data->stack_parm);
3491 }
3492
3493 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3494 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3495
3496 static void
3497 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3498 vec<tree> fnargs)
3499 {
3500 tree parm;
3501 tree orig_fnargs = all->orig_fnargs;
3502 unsigned i = 0;
3503
3504 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3505 {
3506 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3507 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3508 {
3509 rtx tmp, real, imag;
3510 scalar_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3511
3512 real = DECL_RTL (fnargs[i]);
3513 imag = DECL_RTL (fnargs[i + 1]);
3514 if (inner != GET_MODE (real))
3515 {
3516 real = gen_lowpart_SUBREG (inner, real);
3517 imag = gen_lowpart_SUBREG (inner, imag);
3518 }
3519
3520 if (TREE_ADDRESSABLE (parm))
3521 {
3522 rtx rmem, imem;
3523 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3524 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3525 DECL_MODE (parm),
3526 TYPE_ALIGN (TREE_TYPE (parm)));
3527
3528 /* split_complex_arg put the real and imag parts in
3529 pseudos. Move them to memory. */
3530 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3531 set_mem_attributes (tmp, parm, 1);
3532 rmem = adjust_address_nv (tmp, inner, 0);
3533 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3534 push_to_sequence2 (all->first_conversion_insn,
3535 all->last_conversion_insn);
3536 emit_move_insn (rmem, real);
3537 emit_move_insn (imem, imag);
3538 all->first_conversion_insn = get_insns ();
3539 all->last_conversion_insn = get_last_insn ();
3540 end_sequence ();
3541 }
3542 else
3543 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3544 set_parm_rtl (parm, tmp);
3545
3546 real = DECL_INCOMING_RTL (fnargs[i]);
3547 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3548 if (inner != GET_MODE (real))
3549 {
3550 real = gen_lowpart_SUBREG (inner, real);
3551 imag = gen_lowpart_SUBREG (inner, imag);
3552 }
3553 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3554 set_decl_incoming_rtl (parm, tmp, false);
3555 i++;
3556 }
3557 }
3558 }
3559
3560 /* Assign RTL expressions to the function's parameters. This may involve
3561 copying them into registers and using those registers as the DECL_RTL. */
3562
3563 static void
3564 assign_parms (tree fndecl)
3565 {
3566 struct assign_parm_data_all all;
3567 tree parm;
3568 vec<tree> fnargs;
3569 unsigned i;
3570
3571 crtl->args.internal_arg_pointer
3572 = targetm.calls.internal_arg_pointer ();
3573
3574 assign_parms_initialize_all (&all);
3575 fnargs = assign_parms_augmented_arg_list (&all);
3576
3577 FOR_EACH_VEC_ELT (fnargs, i, parm)
3578 {
3579 struct assign_parm_data_one data;
3580
3581 /* Extract the type of PARM; adjust it according to ABI. */
3582 assign_parm_find_data_types (&all, parm, &data);
3583
3584 /* Early out for errors and void parameters. */
3585 if (data.passed_mode == VOIDmode)
3586 {
3587 SET_DECL_RTL (parm, const0_rtx);
3588 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3589 continue;
3590 }
3591
3592 /* Estimate stack alignment from parameter alignment. */
3593 if (SUPPORTS_STACK_ALIGNMENT)
3594 {
3595 unsigned int align
3596 = targetm.calls.function_arg_boundary (data.promoted_mode,
3597 data.passed_type);
3598 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3599 align);
3600 if (TYPE_ALIGN (data.nominal_type) > align)
3601 align = MINIMUM_ALIGNMENT (data.nominal_type,
3602 TYPE_MODE (data.nominal_type),
3603 TYPE_ALIGN (data.nominal_type));
3604 if (crtl->stack_alignment_estimated < align)
3605 {
3606 gcc_assert (!crtl->stack_realign_processed);
3607 crtl->stack_alignment_estimated = align;
3608 }
3609 }
3610
3611 /* Find out where the parameter arrives in this function. */
3612 assign_parm_find_entry_rtl (&all, &data);
3613
3614 /* Find out where stack space for this parameter might be. */
3615 if (assign_parm_is_stack_parm (&all, &data))
3616 {
3617 assign_parm_find_stack_rtl (parm, &data);
3618 assign_parm_adjust_entry_rtl (&data);
3619 }
3620 /* Record permanently how this parm was passed. */
3621 if (data.passed_pointer)
3622 {
3623 rtx incoming_rtl
3624 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3625 data.entry_parm);
3626 set_decl_incoming_rtl (parm, incoming_rtl, true);
3627 }
3628 else
3629 set_decl_incoming_rtl (parm, data.entry_parm, false);
3630
3631 assign_parm_adjust_stack_rtl (&data);
3632
3633 if (assign_parm_setup_block_p (&data))
3634 assign_parm_setup_block (&all, parm, &data);
3635 else if (data.passed_pointer || use_register_for_decl (parm))
3636 assign_parm_setup_reg (&all, parm, &data);
3637 else
3638 assign_parm_setup_stack (&all, parm, &data);
3639
3640 if (cfun->stdarg && !DECL_CHAIN (parm))
3641 assign_parms_setup_varargs (&all, &data, false);
3642
3643 /* Update info on where next arg arrives in registers. */
3644 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3645 data.passed_type, data.named_arg);
3646 }
3647
3648 if (targetm.calls.split_complex_arg)
3649 assign_parms_unsplit_complex (&all, fnargs);
3650
3651 fnargs.release ();
3652
3653 /* Output all parameter conversion instructions (possibly including calls)
3654 now that all parameters have been copied out of hard registers. */
3655 emit_insn (all.first_conversion_insn);
3656
3657 /* Estimate reload stack alignment from scalar return mode. */
3658 if (SUPPORTS_STACK_ALIGNMENT)
3659 {
3660 if (DECL_RESULT (fndecl))
3661 {
3662 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3663 machine_mode mode = TYPE_MODE (type);
3664
3665 if (mode != BLKmode
3666 && mode != VOIDmode
3667 && !AGGREGATE_TYPE_P (type))
3668 {
3669 unsigned int align = GET_MODE_ALIGNMENT (mode);
3670 if (crtl->stack_alignment_estimated < align)
3671 {
3672 gcc_assert (!crtl->stack_realign_processed);
3673 crtl->stack_alignment_estimated = align;
3674 }
3675 }
3676 }
3677 }
3678
3679 /* If we are receiving a struct value address as the first argument, set up
3680 the RTL for the function result. As this might require code to convert
3681 the transmitted address to Pmode, we do this here to ensure that possible
3682 preliminary conversions of the address have been emitted already. */
3683 if (all.function_result_decl)
3684 {
3685 tree result = DECL_RESULT (current_function_decl);
3686 rtx addr = DECL_RTL (all.function_result_decl);
3687 rtx x;
3688
3689 if (DECL_BY_REFERENCE (result))
3690 {
3691 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3692 x = addr;
3693 }
3694 else
3695 {
3696 SET_DECL_VALUE_EXPR (result,
3697 build1 (INDIRECT_REF, TREE_TYPE (result),
3698 all.function_result_decl));
3699 addr = convert_memory_address (Pmode, addr);
3700 x = gen_rtx_MEM (DECL_MODE (result), addr);
3701 set_mem_attributes (x, result, 1);
3702 }
3703
3704 DECL_HAS_VALUE_EXPR_P (result) = 1;
3705
3706 set_parm_rtl (result, x);
3707 }
3708
3709 /* We have aligned all the args, so add space for the pretend args. */
3710 crtl->args.pretend_args_size = all.pretend_args_size;
3711 all.stack_args_size.constant += all.extra_pretend_bytes;
3712 crtl->args.size = all.stack_args_size.constant;
3713
3714 /* Adjust function incoming argument size for alignment and
3715 minimum length. */
3716
3717 crtl->args.size = upper_bound (crtl->args.size, all.reg_parm_stack_space);
3718 crtl->args.size = aligned_upper_bound (crtl->args.size,
3719 PARM_BOUNDARY / BITS_PER_UNIT);
3720
3721 if (ARGS_GROW_DOWNWARD)
3722 {
3723 crtl->args.arg_offset_rtx
3724 = (all.stack_args_size.var == 0
3725 ? gen_int_mode (-all.stack_args_size.constant, Pmode)
3726 : expand_expr (size_diffop (all.stack_args_size.var,
3727 size_int (-all.stack_args_size.constant)),
3728 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3729 }
3730 else
3731 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3732
3733 /* See how many bytes, if any, of its args a function should try to pop
3734 on return. */
3735
3736 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3737 TREE_TYPE (fndecl),
3738 crtl->args.size);
3739
3740 /* For stdarg.h function, save info about
3741 regs and stack space used by the named args. */
3742
3743 crtl->args.info = all.args_so_far_v;
3744
3745 /* Set the rtx used for the function return value. Put this in its
3746 own variable so any optimizers that need this information don't have
3747 to include tree.h. Do this here so it gets done when an inlined
3748 function gets output. */
3749
3750 crtl->return_rtx
3751 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3752 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3753
3754 /* If scalar return value was computed in a pseudo-reg, or was a named
3755 return value that got dumped to the stack, copy that to the hard
3756 return register. */
3757 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3758 {
3759 tree decl_result = DECL_RESULT (fndecl);
3760 rtx decl_rtl = DECL_RTL (decl_result);
3761
3762 if (REG_P (decl_rtl)
3763 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3764 : DECL_REGISTER (decl_result))
3765 {
3766 rtx real_decl_rtl;
3767
3768 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3769 fndecl, true);
3770 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3771 /* The delay slot scheduler assumes that crtl->return_rtx
3772 holds the hard register containing the return value, not a
3773 temporary pseudo. */
3774 crtl->return_rtx = real_decl_rtl;
3775 }
3776 }
3777 }
3778
3779 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3780 For all seen types, gimplify their sizes. */
3781
3782 static tree
3783 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3784 {
3785 tree t = *tp;
3786
3787 *walk_subtrees = 0;
3788 if (TYPE_P (t))
3789 {
3790 if (POINTER_TYPE_P (t))
3791 *walk_subtrees = 1;
3792 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3793 && !TYPE_SIZES_GIMPLIFIED (t))
3794 {
3795 gimplify_type_sizes (t, (gimple_seq *) data);
3796 *walk_subtrees = 1;
3797 }
3798 }
3799
3800 return NULL;
3801 }
3802
3803 /* Gimplify the parameter list for current_function_decl. This involves
3804 evaluating SAVE_EXPRs of variable sized parameters and generating code
3805 to implement callee-copies reference parameters. Returns a sequence of
3806 statements to add to the beginning of the function. */
3807
3808 gimple_seq
3809 gimplify_parameters (gimple_seq *cleanup)
3810 {
3811 struct assign_parm_data_all all;
3812 tree parm;
3813 gimple_seq stmts = NULL;
3814 vec<tree> fnargs;
3815 unsigned i;
3816
3817 assign_parms_initialize_all (&all);
3818 fnargs = assign_parms_augmented_arg_list (&all);
3819
3820 FOR_EACH_VEC_ELT (fnargs, i, parm)
3821 {
3822 struct assign_parm_data_one data;
3823
3824 /* Extract the type of PARM; adjust it according to ABI. */
3825 assign_parm_find_data_types (&all, parm, &data);
3826
3827 /* Early out for errors and void parameters. */
3828 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3829 continue;
3830
3831 /* Update info on where next arg arrives in registers. */
3832 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3833 data.passed_type, data.named_arg);
3834
3835 /* ??? Once upon a time variable_size stuffed parameter list
3836 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3837 turned out to be less than manageable in the gimple world.
3838 Now we have to hunt them down ourselves. */
3839 walk_tree_without_duplicates (&data.passed_type,
3840 gimplify_parm_type, &stmts);
3841
3842 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3843 {
3844 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3845 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3846 }
3847
3848 if (data.passed_pointer)
3849 {
3850 tree type = TREE_TYPE (data.passed_type);
3851 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
3852 type, data.named_arg))
3853 {
3854 tree local, t;
3855
3856 /* For constant-sized objects, this is trivial; for
3857 variable-sized objects, we have to play games. */
3858 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3859 && !(flag_stack_check == GENERIC_STACK_CHECK
3860 && compare_tree_int (DECL_SIZE_UNIT (parm),
3861 STACK_CHECK_MAX_VAR_SIZE) > 0))
3862 {
3863 local = create_tmp_var (type, get_name (parm));
3864 DECL_IGNORED_P (local) = 0;
3865 /* If PARM was addressable, move that flag over
3866 to the local copy, as its address will be taken,
3867 not the PARMs. Keep the parms address taken
3868 as we'll query that flag during gimplification. */
3869 if (TREE_ADDRESSABLE (parm))
3870 TREE_ADDRESSABLE (local) = 1;
3871 else if (TREE_CODE (type) == COMPLEX_TYPE
3872 || TREE_CODE (type) == VECTOR_TYPE)
3873 DECL_GIMPLE_REG_P (local) = 1;
3874
3875 if (!is_gimple_reg (local)
3876 && flag_stack_reuse != SR_NONE)
3877 {
3878 tree clobber = build_constructor (type, NULL);
3879 gimple *clobber_stmt;
3880 TREE_THIS_VOLATILE (clobber) = 1;
3881 clobber_stmt = gimple_build_assign (local, clobber);
3882 gimple_seq_add_stmt (cleanup, clobber_stmt);
3883 }
3884 }
3885 else
3886 {
3887 tree ptr_type, addr;
3888
3889 ptr_type = build_pointer_type (type);
3890 addr = create_tmp_reg (ptr_type, get_name (parm));
3891 DECL_IGNORED_P (addr) = 0;
3892 local = build_fold_indirect_ref (addr);
3893
3894 t = build_alloca_call_expr (DECL_SIZE_UNIT (parm),
3895 DECL_ALIGN (parm),
3896 max_int_size_in_bytes (type));
3897 /* The call has been built for a variable-sized object. */
3898 CALL_ALLOCA_FOR_VAR_P (t) = 1;
3899 t = fold_convert (ptr_type, t);
3900 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3901 gimplify_and_add (t, &stmts);
3902 }
3903
3904 gimplify_assign (local, parm, &stmts);
3905
3906 SET_DECL_VALUE_EXPR (parm, local);
3907 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3908 }
3909 }
3910 }
3911
3912 fnargs.release ();
3913
3914 return stmts;
3915 }
3916 \f
3917 /* Compute the size and offset from the start of the stacked arguments for a
3918 parm passed in mode PASSED_MODE and with type TYPE.
3919
3920 INITIAL_OFFSET_PTR points to the current offset into the stacked
3921 arguments.
3922
3923 The starting offset and size for this parm are returned in
3924 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3925 nonzero, the offset is that of stack slot, which is returned in
3926 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3927 padding required from the initial offset ptr to the stack slot.
3928
3929 IN_REGS is nonzero if the argument will be passed in registers. It will
3930 never be set if REG_PARM_STACK_SPACE is not defined.
3931
3932 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3933 for arguments which are passed in registers.
3934
3935 FNDECL is the function in which the argument was defined.
3936
3937 There are two types of rounding that are done. The first, controlled by
3938 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3939 argument list to be aligned to the specific boundary (in bits). This
3940 rounding affects the initial and starting offsets, but not the argument
3941 size.
3942
3943 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3944 optionally rounds the size of the parm to PARM_BOUNDARY. The
3945 initial offset is not affected by this rounding, while the size always
3946 is and the starting offset may be. */
3947
3948 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3949 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3950 callers pass in the total size of args so far as
3951 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3952
3953 void
3954 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
3955 int reg_parm_stack_space, int partial,
3956 tree fndecl ATTRIBUTE_UNUSED,
3957 struct args_size *initial_offset_ptr,
3958 struct locate_and_pad_arg_data *locate)
3959 {
3960 tree sizetree;
3961 pad_direction where_pad;
3962 unsigned int boundary, round_boundary;
3963 int part_size_in_regs;
3964
3965 /* If we have found a stack parm before we reach the end of the
3966 area reserved for registers, skip that area. */
3967 if (! in_regs)
3968 {
3969 if (reg_parm_stack_space > 0)
3970 {
3971 if (initial_offset_ptr->var
3972 || !ordered_p (initial_offset_ptr->constant,
3973 reg_parm_stack_space))
3974 {
3975 initial_offset_ptr->var
3976 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3977 ssize_int (reg_parm_stack_space));
3978 initial_offset_ptr->constant = 0;
3979 }
3980 else
3981 initial_offset_ptr->constant
3982 = ordered_max (initial_offset_ptr->constant,
3983 reg_parm_stack_space);
3984 }
3985 }
3986
3987 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3988
3989 sizetree = (type
3990 ? arg_size_in_bytes (type)
3991 : size_int (GET_MODE_SIZE (passed_mode)));
3992 where_pad = targetm.calls.function_arg_padding (passed_mode, type);
3993 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
3994 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
3995 type);
3996 locate->where_pad = where_pad;
3997
3998 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3999 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
4000 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
4001
4002 locate->boundary = boundary;
4003
4004 if (SUPPORTS_STACK_ALIGNMENT)
4005 {
4006 /* stack_alignment_estimated can't change after stack has been
4007 realigned. */
4008 if (crtl->stack_alignment_estimated < boundary)
4009 {
4010 if (!crtl->stack_realign_processed)
4011 crtl->stack_alignment_estimated = boundary;
4012 else
4013 {
4014 /* If stack is realigned and stack alignment value
4015 hasn't been finalized, it is OK not to increase
4016 stack_alignment_estimated. The bigger alignment
4017 requirement is recorded in stack_alignment_needed
4018 below. */
4019 gcc_assert (!crtl->stack_realign_finalized
4020 && crtl->stack_realign_needed);
4021 }
4022 }
4023 }
4024
4025 if (ARGS_GROW_DOWNWARD)
4026 {
4027 locate->slot_offset.constant = -initial_offset_ptr->constant;
4028 if (initial_offset_ptr->var)
4029 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4030 initial_offset_ptr->var);
4031
4032 {
4033 tree s2 = sizetree;
4034 if (where_pad != PAD_NONE
4035 && (!tree_fits_uhwi_p (sizetree)
4036 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4037 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4038 SUB_PARM_SIZE (locate->slot_offset, s2);
4039 }
4040
4041 locate->slot_offset.constant += part_size_in_regs;
4042
4043 if (!in_regs || reg_parm_stack_space > 0)
4044 pad_to_arg_alignment (&locate->slot_offset, boundary,
4045 &locate->alignment_pad);
4046
4047 locate->size.constant = (-initial_offset_ptr->constant
4048 - locate->slot_offset.constant);
4049 if (initial_offset_ptr->var)
4050 locate->size.var = size_binop (MINUS_EXPR,
4051 size_binop (MINUS_EXPR,
4052 ssize_int (0),
4053 initial_offset_ptr->var),
4054 locate->slot_offset.var);
4055
4056 /* Pad_below needs the pre-rounded size to know how much to pad
4057 below. */
4058 locate->offset = locate->slot_offset;
4059 if (where_pad == PAD_DOWNWARD)
4060 pad_below (&locate->offset, passed_mode, sizetree);
4061
4062 }
4063 else
4064 {
4065 if (!in_regs || reg_parm_stack_space > 0)
4066 pad_to_arg_alignment (initial_offset_ptr, boundary,
4067 &locate->alignment_pad);
4068 locate->slot_offset = *initial_offset_ptr;
4069
4070 #ifdef PUSH_ROUNDING
4071 if (passed_mode != BLKmode)
4072 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4073 #endif
4074
4075 /* Pad_below needs the pre-rounded size to know how much to pad below
4076 so this must be done before rounding up. */
4077 locate->offset = locate->slot_offset;
4078 if (where_pad == PAD_DOWNWARD)
4079 pad_below (&locate->offset, passed_mode, sizetree);
4080
4081 if (where_pad != PAD_NONE
4082 && (!tree_fits_uhwi_p (sizetree)
4083 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4084 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4085
4086 ADD_PARM_SIZE (locate->size, sizetree);
4087
4088 locate->size.constant -= part_size_in_regs;
4089 }
4090
4091 locate->offset.constant
4092 += targetm.calls.function_arg_offset (passed_mode, type);
4093 }
4094
4095 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4096 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4097
4098 static void
4099 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4100 struct args_size *alignment_pad)
4101 {
4102 tree save_var = NULL_TREE;
4103 poly_int64 save_constant = 0;
4104 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4105 poly_int64 sp_offset = STACK_POINTER_OFFSET;
4106
4107 #ifdef SPARC_STACK_BOUNDARY_HACK
4108 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4109 the real alignment of %sp. However, when it does this, the
4110 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4111 if (SPARC_STACK_BOUNDARY_HACK)
4112 sp_offset = 0;
4113 #endif
4114
4115 if (boundary > PARM_BOUNDARY)
4116 {
4117 save_var = offset_ptr->var;
4118 save_constant = offset_ptr->constant;
4119 }
4120
4121 alignment_pad->var = NULL_TREE;
4122 alignment_pad->constant = 0;
4123
4124 if (boundary > BITS_PER_UNIT)
4125 {
4126 int misalign;
4127 if (offset_ptr->var
4128 || !known_misalignment (offset_ptr->constant + sp_offset,
4129 boundary_in_bytes, &misalign))
4130 {
4131 tree sp_offset_tree = ssize_int (sp_offset);
4132 tree offset = size_binop (PLUS_EXPR,
4133 ARGS_SIZE_TREE (*offset_ptr),
4134 sp_offset_tree);
4135 tree rounded;
4136 if (ARGS_GROW_DOWNWARD)
4137 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4138 else
4139 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4140
4141 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4142 /* ARGS_SIZE_TREE includes constant term. */
4143 offset_ptr->constant = 0;
4144 if (boundary > PARM_BOUNDARY)
4145 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4146 save_var);
4147 }
4148 else
4149 {
4150 if (ARGS_GROW_DOWNWARD)
4151 offset_ptr->constant -= misalign;
4152 else
4153 offset_ptr->constant += -misalign & (boundary_in_bytes - 1);
4154
4155 if (boundary > PARM_BOUNDARY)
4156 alignment_pad->constant = offset_ptr->constant - save_constant;
4157 }
4158 }
4159 }
4160
4161 static void
4162 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4163 {
4164 unsigned int align = PARM_BOUNDARY / BITS_PER_UNIT;
4165 int misalign;
4166 if (passed_mode != BLKmode
4167 && known_misalignment (GET_MODE_SIZE (passed_mode), align, &misalign))
4168 offset_ptr->constant += -misalign & (align - 1);
4169 else
4170 {
4171 if (TREE_CODE (sizetree) != INTEGER_CST
4172 || (TREE_INT_CST_LOW (sizetree) & (align - 1)) != 0)
4173 {
4174 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4175 tree s2 = round_up (sizetree, align);
4176 /* Add it in. */
4177 ADD_PARM_SIZE (*offset_ptr, s2);
4178 SUB_PARM_SIZE (*offset_ptr, sizetree);
4179 }
4180 }
4181 }
4182 \f
4183
4184 /* True if register REGNO was alive at a place where `setjmp' was
4185 called and was set more than once or is an argument. Such regs may
4186 be clobbered by `longjmp'. */
4187
4188 static bool
4189 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4190 {
4191 /* There appear to be cases where some local vars never reach the
4192 backend but have bogus regnos. */
4193 if (regno >= max_reg_num ())
4194 return false;
4195
4196 return ((REG_N_SETS (regno) > 1
4197 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4198 regno))
4199 && REGNO_REG_SET_P (setjmp_crosses, regno));
4200 }
4201
4202 /* Walk the tree of blocks describing the binding levels within a
4203 function and warn about variables the might be killed by setjmp or
4204 vfork. This is done after calling flow_analysis before register
4205 allocation since that will clobber the pseudo-regs to hard
4206 regs. */
4207
4208 static void
4209 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4210 {
4211 tree decl, sub;
4212
4213 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4214 {
4215 if (VAR_P (decl)
4216 && DECL_RTL_SET_P (decl)
4217 && REG_P (DECL_RTL (decl))
4218 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4219 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4220 " %<longjmp%> or %<vfork%>", decl);
4221 }
4222
4223 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4224 setjmp_vars_warning (setjmp_crosses, sub);
4225 }
4226
4227 /* Do the appropriate part of setjmp_vars_warning
4228 but for arguments instead of local variables. */
4229
4230 static void
4231 setjmp_args_warning (bitmap setjmp_crosses)
4232 {
4233 tree decl;
4234 for (decl = DECL_ARGUMENTS (current_function_decl);
4235 decl; decl = DECL_CHAIN (decl))
4236 if (DECL_RTL (decl) != 0
4237 && REG_P (DECL_RTL (decl))
4238 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4239 warning (OPT_Wclobbered,
4240 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4241 decl);
4242 }
4243
4244 /* Generate warning messages for variables live across setjmp. */
4245
4246 void
4247 generate_setjmp_warnings (void)
4248 {
4249 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4250
4251 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4252 || bitmap_empty_p (setjmp_crosses))
4253 return;
4254
4255 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4256 setjmp_args_warning (setjmp_crosses);
4257 }
4258
4259 \f
4260 /* Reverse the order of elements in the fragment chain T of blocks,
4261 and return the new head of the chain (old last element).
4262 In addition to that clear BLOCK_SAME_RANGE flags when needed
4263 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4264 its super fragment origin. */
4265
4266 static tree
4267 block_fragments_nreverse (tree t)
4268 {
4269 tree prev = 0, block, next, prev_super = 0;
4270 tree super = BLOCK_SUPERCONTEXT (t);
4271 if (BLOCK_FRAGMENT_ORIGIN (super))
4272 super = BLOCK_FRAGMENT_ORIGIN (super);
4273 for (block = t; block; block = next)
4274 {
4275 next = BLOCK_FRAGMENT_CHAIN (block);
4276 BLOCK_FRAGMENT_CHAIN (block) = prev;
4277 if ((prev && !BLOCK_SAME_RANGE (prev))
4278 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4279 != prev_super))
4280 BLOCK_SAME_RANGE (block) = 0;
4281 prev_super = BLOCK_SUPERCONTEXT (block);
4282 BLOCK_SUPERCONTEXT (block) = super;
4283 prev = block;
4284 }
4285 t = BLOCK_FRAGMENT_ORIGIN (t);
4286 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4287 != prev_super)
4288 BLOCK_SAME_RANGE (t) = 0;
4289 BLOCK_SUPERCONTEXT (t) = super;
4290 return prev;
4291 }
4292
4293 /* Reverse the order of elements in the chain T of blocks,
4294 and return the new head of the chain (old last element).
4295 Also do the same on subblocks and reverse the order of elements
4296 in BLOCK_FRAGMENT_CHAIN as well. */
4297
4298 static tree
4299 blocks_nreverse_all (tree t)
4300 {
4301 tree prev = 0, block, next;
4302 for (block = t; block; block = next)
4303 {
4304 next = BLOCK_CHAIN (block);
4305 BLOCK_CHAIN (block) = prev;
4306 if (BLOCK_FRAGMENT_CHAIN (block)
4307 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4308 {
4309 BLOCK_FRAGMENT_CHAIN (block)
4310 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4311 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4312 BLOCK_SAME_RANGE (block) = 0;
4313 }
4314 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4315 prev = block;
4316 }
4317 return prev;
4318 }
4319
4320
4321 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4322 and create duplicate blocks. */
4323 /* ??? Need an option to either create block fragments or to create
4324 abstract origin duplicates of a source block. It really depends
4325 on what optimization has been performed. */
4326
4327 void
4328 reorder_blocks (void)
4329 {
4330 tree block = DECL_INITIAL (current_function_decl);
4331
4332 if (block == NULL_TREE)
4333 return;
4334
4335 auto_vec<tree, 10> block_stack;
4336
4337 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4338 clear_block_marks (block);
4339
4340 /* Prune the old trees away, so that they don't get in the way. */
4341 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4342 BLOCK_CHAIN (block) = NULL_TREE;
4343
4344 /* Recreate the block tree from the note nesting. */
4345 reorder_blocks_1 (get_insns (), block, &block_stack);
4346 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4347 }
4348
4349 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4350
4351 void
4352 clear_block_marks (tree block)
4353 {
4354 while (block)
4355 {
4356 TREE_ASM_WRITTEN (block) = 0;
4357 clear_block_marks (BLOCK_SUBBLOCKS (block));
4358 block = BLOCK_CHAIN (block);
4359 }
4360 }
4361
4362 static void
4363 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4364 vec<tree> *p_block_stack)
4365 {
4366 rtx_insn *insn;
4367 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4368
4369 for (insn = insns; insn; insn = NEXT_INSN (insn))
4370 {
4371 if (NOTE_P (insn))
4372 {
4373 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4374 {
4375 tree block = NOTE_BLOCK (insn);
4376 tree origin;
4377
4378 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4379 origin = block;
4380
4381 if (prev_end)
4382 BLOCK_SAME_RANGE (prev_end) = 0;
4383 prev_end = NULL_TREE;
4384
4385 /* If we have seen this block before, that means it now
4386 spans multiple address regions. Create a new fragment. */
4387 if (TREE_ASM_WRITTEN (block))
4388 {
4389 tree new_block = copy_node (block);
4390
4391 BLOCK_SAME_RANGE (new_block) = 0;
4392 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4393 BLOCK_FRAGMENT_CHAIN (new_block)
4394 = BLOCK_FRAGMENT_CHAIN (origin);
4395 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4396
4397 NOTE_BLOCK (insn) = new_block;
4398 block = new_block;
4399 }
4400
4401 if (prev_beg == current_block && prev_beg)
4402 BLOCK_SAME_RANGE (block) = 1;
4403
4404 prev_beg = origin;
4405
4406 BLOCK_SUBBLOCKS (block) = 0;
4407 TREE_ASM_WRITTEN (block) = 1;
4408 /* When there's only one block for the entire function,
4409 current_block == block and we mustn't do this, it
4410 will cause infinite recursion. */
4411 if (block != current_block)
4412 {
4413 tree super;
4414 if (block != origin)
4415 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4416 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4417 (origin))
4418 == current_block);
4419 if (p_block_stack->is_empty ())
4420 super = current_block;
4421 else
4422 {
4423 super = p_block_stack->last ();
4424 gcc_assert (super == current_block
4425 || BLOCK_FRAGMENT_ORIGIN (super)
4426 == current_block);
4427 }
4428 BLOCK_SUPERCONTEXT (block) = super;
4429 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4430 BLOCK_SUBBLOCKS (current_block) = block;
4431 current_block = origin;
4432 }
4433 p_block_stack->safe_push (block);
4434 }
4435 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4436 {
4437 NOTE_BLOCK (insn) = p_block_stack->pop ();
4438 current_block = BLOCK_SUPERCONTEXT (current_block);
4439 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4440 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4441 prev_beg = NULL_TREE;
4442 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4443 ? NOTE_BLOCK (insn) : NULL_TREE;
4444 }
4445 }
4446 else
4447 {
4448 prev_beg = NULL_TREE;
4449 if (prev_end)
4450 BLOCK_SAME_RANGE (prev_end) = 0;
4451 prev_end = NULL_TREE;
4452 }
4453 }
4454 }
4455
4456 /* Reverse the order of elements in the chain T of blocks,
4457 and return the new head of the chain (old last element). */
4458
4459 tree
4460 blocks_nreverse (tree t)
4461 {
4462 tree prev = 0, block, next;
4463 for (block = t; block; block = next)
4464 {
4465 next = BLOCK_CHAIN (block);
4466 BLOCK_CHAIN (block) = prev;
4467 prev = block;
4468 }
4469 return prev;
4470 }
4471
4472 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4473 by modifying the last node in chain 1 to point to chain 2. */
4474
4475 tree
4476 block_chainon (tree op1, tree op2)
4477 {
4478 tree t1;
4479
4480 if (!op1)
4481 return op2;
4482 if (!op2)
4483 return op1;
4484
4485 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4486 continue;
4487 BLOCK_CHAIN (t1) = op2;
4488
4489 #ifdef ENABLE_TREE_CHECKING
4490 {
4491 tree t2;
4492 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4493 gcc_assert (t2 != t1);
4494 }
4495 #endif
4496
4497 return op1;
4498 }
4499
4500 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4501 non-NULL, list them all into VECTOR, in a depth-first preorder
4502 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4503 blocks. */
4504
4505 static int
4506 all_blocks (tree block, tree *vector)
4507 {
4508 int n_blocks = 0;
4509
4510 while (block)
4511 {
4512 TREE_ASM_WRITTEN (block) = 0;
4513
4514 /* Record this block. */
4515 if (vector)
4516 vector[n_blocks] = block;
4517
4518 ++n_blocks;
4519
4520 /* Record the subblocks, and their subblocks... */
4521 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4522 vector ? vector + n_blocks : 0);
4523 block = BLOCK_CHAIN (block);
4524 }
4525
4526 return n_blocks;
4527 }
4528
4529 /* Return a vector containing all the blocks rooted at BLOCK. The
4530 number of elements in the vector is stored in N_BLOCKS_P. The
4531 vector is dynamically allocated; it is the caller's responsibility
4532 to call `free' on the pointer returned. */
4533
4534 static tree *
4535 get_block_vector (tree block, int *n_blocks_p)
4536 {
4537 tree *block_vector;
4538
4539 *n_blocks_p = all_blocks (block, NULL);
4540 block_vector = XNEWVEC (tree, *n_blocks_p);
4541 all_blocks (block, block_vector);
4542
4543 return block_vector;
4544 }
4545
4546 static GTY(()) int next_block_index = 2;
4547
4548 /* Set BLOCK_NUMBER for all the blocks in FN. */
4549
4550 void
4551 number_blocks (tree fn)
4552 {
4553 int i;
4554 int n_blocks;
4555 tree *block_vector;
4556
4557 /* For XCOFF debugging output, we start numbering the blocks
4558 from 1 within each function, rather than keeping a running
4559 count. */
4560 #if defined (XCOFF_DEBUGGING_INFO)
4561 if (write_symbols == XCOFF_DEBUG)
4562 next_block_index = 1;
4563 #endif
4564
4565 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4566
4567 /* The top-level BLOCK isn't numbered at all. */
4568 for (i = 1; i < n_blocks; ++i)
4569 /* We number the blocks from two. */
4570 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4571
4572 free (block_vector);
4573
4574 return;
4575 }
4576
4577 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4578
4579 DEBUG_FUNCTION tree
4580 debug_find_var_in_block_tree (tree var, tree block)
4581 {
4582 tree t;
4583
4584 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4585 if (t == var)
4586 return block;
4587
4588 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4589 {
4590 tree ret = debug_find_var_in_block_tree (var, t);
4591 if (ret)
4592 return ret;
4593 }
4594
4595 return NULL_TREE;
4596 }
4597 \f
4598 /* Keep track of whether we're in a dummy function context. If we are,
4599 we don't want to invoke the set_current_function hook, because we'll
4600 get into trouble if the hook calls target_reinit () recursively or
4601 when the initial initialization is not yet complete. */
4602
4603 static bool in_dummy_function;
4604
4605 /* Invoke the target hook when setting cfun. Update the optimization options
4606 if the function uses different options than the default. */
4607
4608 static void
4609 invoke_set_current_function_hook (tree fndecl)
4610 {
4611 if (!in_dummy_function)
4612 {
4613 tree opts = ((fndecl)
4614 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4615 : optimization_default_node);
4616
4617 if (!opts)
4618 opts = optimization_default_node;
4619
4620 /* Change optimization options if needed. */
4621 if (optimization_current_node != opts)
4622 {
4623 optimization_current_node = opts;
4624 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4625 }
4626
4627 targetm.set_current_function (fndecl);
4628 this_fn_optabs = this_target_optabs;
4629
4630 /* Initialize global alignment variables after op. */
4631 parse_alignment_opts ();
4632
4633 if (opts != optimization_default_node)
4634 {
4635 init_tree_optimization_optabs (opts);
4636 if (TREE_OPTIMIZATION_OPTABS (opts))
4637 this_fn_optabs = (struct target_optabs *)
4638 TREE_OPTIMIZATION_OPTABS (opts);
4639 }
4640 }
4641 }
4642
4643 /* cfun should never be set directly; use this function. */
4644
4645 void
4646 set_cfun (struct function *new_cfun, bool force)
4647 {
4648 if (cfun != new_cfun || force)
4649 {
4650 cfun = new_cfun;
4651 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4652 redirect_edge_var_map_empty ();
4653 }
4654 }
4655
4656 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4657
4658 static vec<function *> cfun_stack;
4659
4660 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4661 current_function_decl accordingly. */
4662
4663 void
4664 push_cfun (struct function *new_cfun)
4665 {
4666 gcc_assert ((!cfun && !current_function_decl)
4667 || (cfun && current_function_decl == cfun->decl));
4668 cfun_stack.safe_push (cfun);
4669 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4670 set_cfun (new_cfun);
4671 }
4672
4673 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4674
4675 void
4676 pop_cfun (void)
4677 {
4678 struct function *new_cfun = cfun_stack.pop ();
4679 /* When in_dummy_function, we do have a cfun but current_function_decl is
4680 NULL. We also allow pushing NULL cfun and subsequently changing
4681 current_function_decl to something else and have both restored by
4682 pop_cfun. */
4683 gcc_checking_assert (in_dummy_function
4684 || !cfun
4685 || current_function_decl == cfun->decl);
4686 set_cfun (new_cfun);
4687 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4688 }
4689
4690 /* Return value of funcdef and increase it. */
4691 int
4692 get_next_funcdef_no (void)
4693 {
4694 return funcdef_no++;
4695 }
4696
4697 /* Return value of funcdef. */
4698 int
4699 get_last_funcdef_no (void)
4700 {
4701 return funcdef_no;
4702 }
4703
4704 /* Allocate a function structure for FNDECL and set its contents
4705 to the defaults. Set cfun to the newly-allocated object.
4706 Some of the helper functions invoked during initialization assume
4707 that cfun has already been set. Therefore, assign the new object
4708 directly into cfun and invoke the back end hook explicitly at the
4709 very end, rather than initializing a temporary and calling set_cfun
4710 on it.
4711
4712 ABSTRACT_P is true if this is a function that will never be seen by
4713 the middle-end. Such functions are front-end concepts (like C++
4714 function templates) that do not correspond directly to functions
4715 placed in object files. */
4716
4717 void
4718 allocate_struct_function (tree fndecl, bool abstract_p)
4719 {
4720 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4721
4722 cfun = ggc_cleared_alloc<function> ();
4723
4724 init_eh_for_function ();
4725
4726 if (init_machine_status)
4727 cfun->machine = (*init_machine_status) ();
4728
4729 #ifdef OVERRIDE_ABI_FORMAT
4730 OVERRIDE_ABI_FORMAT (fndecl);
4731 #endif
4732
4733 if (fndecl != NULL_TREE)
4734 {
4735 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4736 cfun->decl = fndecl;
4737 current_function_funcdef_no = get_next_funcdef_no ();
4738 }
4739
4740 invoke_set_current_function_hook (fndecl);
4741
4742 if (fndecl != NULL_TREE)
4743 {
4744 tree result = DECL_RESULT (fndecl);
4745
4746 if (!abstract_p)
4747 {
4748 /* Now that we have activated any function-specific attributes
4749 that might affect layout, particularly vector modes, relayout
4750 each of the parameters and the result. */
4751 relayout_decl (result);
4752 for (tree parm = DECL_ARGUMENTS (fndecl); parm;
4753 parm = DECL_CHAIN (parm))
4754 relayout_decl (parm);
4755
4756 /* Similarly relayout the function decl. */
4757 targetm.target_option.relayout_function (fndecl);
4758 }
4759
4760 if (!abstract_p && aggregate_value_p (result, fndecl))
4761 {
4762 #ifdef PCC_STATIC_STRUCT_RETURN
4763 cfun->returns_pcc_struct = 1;
4764 #endif
4765 cfun->returns_struct = 1;
4766 }
4767
4768 cfun->stdarg = stdarg_p (fntype);
4769
4770 /* Assume all registers in stdarg functions need to be saved. */
4771 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4772 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4773
4774 /* ??? This could be set on a per-function basis by the front-end
4775 but is this worth the hassle? */
4776 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4777 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4778
4779 if (!profile_flag && !flag_instrument_function_entry_exit)
4780 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4781 }
4782
4783 /* Don't enable begin stmt markers if var-tracking at assignments is
4784 disabled. The markers make little sense without the variable
4785 binding annotations among them. */
4786 cfun->debug_nonbind_markers = lang_hooks.emits_begin_stmt
4787 && MAY_HAVE_DEBUG_MARKER_STMTS;
4788 }
4789
4790 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4791 instead of just setting it. */
4792
4793 void
4794 push_struct_function (tree fndecl)
4795 {
4796 /* When in_dummy_function we might be in the middle of a pop_cfun and
4797 current_function_decl and cfun may not match. */
4798 gcc_assert (in_dummy_function
4799 || (!cfun && !current_function_decl)
4800 || (cfun && current_function_decl == cfun->decl));
4801 cfun_stack.safe_push (cfun);
4802 current_function_decl = fndecl;
4803 allocate_struct_function (fndecl, false);
4804 }
4805
4806 /* Reset crtl and other non-struct-function variables to defaults as
4807 appropriate for emitting rtl at the start of a function. */
4808
4809 static void
4810 prepare_function_start (void)
4811 {
4812 gcc_assert (!get_last_insn ());
4813 init_temp_slots ();
4814 init_emit ();
4815 init_varasm_status ();
4816 init_expr ();
4817 default_rtl_profile ();
4818
4819 if (flag_stack_usage_info)
4820 {
4821 cfun->su = ggc_cleared_alloc<stack_usage> ();
4822 cfun->su->static_stack_size = -1;
4823 }
4824
4825 cse_not_expected = ! optimize;
4826
4827 /* Caller save not needed yet. */
4828 caller_save_needed = 0;
4829
4830 /* We haven't done register allocation yet. */
4831 reg_renumber = 0;
4832
4833 /* Indicate that we have not instantiated virtual registers yet. */
4834 virtuals_instantiated = 0;
4835
4836 /* Indicate that we want CONCATs now. */
4837 generating_concat_p = 1;
4838
4839 /* Indicate we have no need of a frame pointer yet. */
4840 frame_pointer_needed = 0;
4841 }
4842
4843 void
4844 push_dummy_function (bool with_decl)
4845 {
4846 tree fn_decl, fn_type, fn_result_decl;
4847
4848 gcc_assert (!in_dummy_function);
4849 in_dummy_function = true;
4850
4851 if (with_decl)
4852 {
4853 fn_type = build_function_type_list (void_type_node, NULL_TREE);
4854 fn_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
4855 fn_type);
4856 fn_result_decl = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
4857 NULL_TREE, void_type_node);
4858 DECL_RESULT (fn_decl) = fn_result_decl;
4859 }
4860 else
4861 fn_decl = NULL_TREE;
4862
4863 push_struct_function (fn_decl);
4864 }
4865
4866 /* Initialize the rtl expansion mechanism so that we can do simple things
4867 like generate sequences. This is used to provide a context during global
4868 initialization of some passes. You must call expand_dummy_function_end
4869 to exit this context. */
4870
4871 void
4872 init_dummy_function_start (void)
4873 {
4874 push_dummy_function (false);
4875 prepare_function_start ();
4876 }
4877
4878 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4879 and initialize static variables for generating RTL for the statements
4880 of the function. */
4881
4882 void
4883 init_function_start (tree subr)
4884 {
4885 /* Initialize backend, if needed. */
4886 initialize_rtl ();
4887
4888 prepare_function_start ();
4889 decide_function_section (subr);
4890
4891 /* Warn if this value is an aggregate type,
4892 regardless of which calling convention we are using for it. */
4893 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4894 warning (OPT_Waggregate_return, "function returns an aggregate");
4895 }
4896
4897 /* Expand code to verify the stack_protect_guard. This is invoked at
4898 the end of a function to be protected. */
4899
4900 void
4901 stack_protect_epilogue (void)
4902 {
4903 tree guard_decl = crtl->stack_protect_guard_decl;
4904 rtx_code_label *label = gen_label_rtx ();
4905 rtx x, y;
4906 rtx_insn *seq = NULL;
4907
4908 x = expand_normal (crtl->stack_protect_guard);
4909
4910 if (targetm.have_stack_protect_combined_test () && guard_decl)
4911 {
4912 gcc_assert (DECL_P (guard_decl));
4913 y = DECL_RTL (guard_decl);
4914 /* Allow the target to compute address of Y and compare it with X without
4915 leaking Y into a register. This combined address + compare pattern
4916 allows the target to prevent spilling of any intermediate results by
4917 splitting it after register allocator. */
4918 seq = targetm.gen_stack_protect_combined_test (x, y, label);
4919 }
4920 else
4921 {
4922 if (guard_decl)
4923 y = expand_normal (guard_decl);
4924 else
4925 y = const0_rtx;
4926
4927 /* Allow the target to compare Y with X without leaking either into
4928 a register. */
4929 if (targetm.have_stack_protect_test ())
4930 seq = targetm.gen_stack_protect_test (x, y, label);
4931 }
4932
4933 if (seq)
4934 emit_insn (seq);
4935 else
4936 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4937
4938 /* The noreturn predictor has been moved to the tree level. The rtl-level
4939 predictors estimate this branch about 20%, which isn't enough to get
4940 things moved out of line. Since this is the only extant case of adding
4941 a noreturn function at the rtl level, it doesn't seem worth doing ought
4942 except adding the prediction by hand. */
4943 rtx_insn *tmp = get_last_insn ();
4944 if (JUMP_P (tmp))
4945 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4946
4947 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
4948 free_temp_slots ();
4949 emit_label (label);
4950 }
4951 \f
4952 /* Start the RTL for a new function, and set variables used for
4953 emitting RTL.
4954 SUBR is the FUNCTION_DECL node.
4955 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4956 the function's parameters, which must be run at any return statement. */
4957
4958 void
4959 expand_function_start (tree subr)
4960 {
4961 /* Make sure volatile mem refs aren't considered
4962 valid operands of arithmetic insns. */
4963 init_recog_no_volatile ();
4964
4965 crtl->profile
4966 = (profile_flag
4967 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4968
4969 crtl->limit_stack
4970 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4971
4972 /* Make the label for return statements to jump to. Do not special
4973 case machines with special return instructions -- they will be
4974 handled later during jump, ifcvt, or epilogue creation. */
4975 return_label = gen_label_rtx ();
4976
4977 /* Initialize rtx used to return the value. */
4978 /* Do this before assign_parms so that we copy the struct value address
4979 before any library calls that assign parms might generate. */
4980
4981 /* Decide whether to return the value in memory or in a register. */
4982 tree res = DECL_RESULT (subr);
4983 if (aggregate_value_p (res, subr))
4984 {
4985 /* Returning something that won't go in a register. */
4986 rtx value_address = 0;
4987
4988 #ifdef PCC_STATIC_STRUCT_RETURN
4989 if (cfun->returns_pcc_struct)
4990 {
4991 int size = int_size_in_bytes (TREE_TYPE (res));
4992 value_address = assemble_static_space (size);
4993 }
4994 else
4995 #endif
4996 {
4997 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4998 /* Expect to be passed the address of a place to store the value.
4999 If it is passed as an argument, assign_parms will take care of
5000 it. */
5001 if (sv)
5002 {
5003 value_address = gen_reg_rtx (Pmode);
5004 emit_move_insn (value_address, sv);
5005 }
5006 }
5007 if (value_address)
5008 {
5009 rtx x = value_address;
5010 if (!DECL_BY_REFERENCE (res))
5011 {
5012 x = gen_rtx_MEM (DECL_MODE (res), x);
5013 set_mem_attributes (x, res, 1);
5014 }
5015 set_parm_rtl (res, x);
5016 }
5017 }
5018 else if (DECL_MODE (res) == VOIDmode)
5019 /* If return mode is void, this decl rtl should not be used. */
5020 set_parm_rtl (res, NULL_RTX);
5021 else
5022 {
5023 /* Compute the return values into a pseudo reg, which we will copy
5024 into the true return register after the cleanups are done. */
5025 tree return_type = TREE_TYPE (res);
5026
5027 /* If we may coalesce this result, make sure it has the expected mode
5028 in case it was promoted. But we need not bother about BLKmode. */
5029 machine_mode promoted_mode
5030 = flag_tree_coalesce_vars && is_gimple_reg (res)
5031 ? promote_ssa_mode (ssa_default_def (cfun, res), NULL)
5032 : BLKmode;
5033
5034 if (promoted_mode != BLKmode)
5035 set_parm_rtl (res, gen_reg_rtx (promoted_mode));
5036 else if (TYPE_MODE (return_type) != BLKmode
5037 && targetm.calls.return_in_msb (return_type))
5038 /* expand_function_end will insert the appropriate padding in
5039 this case. Use the return value's natural (unpadded) mode
5040 within the function proper. */
5041 set_parm_rtl (res, gen_reg_rtx (TYPE_MODE (return_type)));
5042 else
5043 {
5044 /* In order to figure out what mode to use for the pseudo, we
5045 figure out what the mode of the eventual return register will
5046 actually be, and use that. */
5047 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
5048
5049 /* Structures that are returned in registers are not
5050 aggregate_value_p, so we may see a PARALLEL or a REG. */
5051 if (REG_P (hard_reg))
5052 set_parm_rtl (res, gen_reg_rtx (GET_MODE (hard_reg)));
5053 else
5054 {
5055 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5056 set_parm_rtl (res, gen_group_rtx (hard_reg));
5057 }
5058 }
5059
5060 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5061 result to the real return register(s). */
5062 DECL_REGISTER (res) = 1;
5063 }
5064
5065 /* Initialize rtx for parameters and local variables.
5066 In some cases this requires emitting insns. */
5067 assign_parms (subr);
5068
5069 /* If function gets a static chain arg, store it. */
5070 if (cfun->static_chain_decl)
5071 {
5072 tree parm = cfun->static_chain_decl;
5073 rtx local, chain;
5074 rtx_insn *insn;
5075 int unsignedp;
5076
5077 local = gen_reg_rtx (promote_decl_mode (parm, &unsignedp));
5078 chain = targetm.calls.static_chain (current_function_decl, true);
5079
5080 set_decl_incoming_rtl (parm, chain, false);
5081 set_parm_rtl (parm, local);
5082 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5083
5084 if (GET_MODE (local) != GET_MODE (chain))
5085 {
5086 convert_move (local, chain, unsignedp);
5087 insn = get_last_insn ();
5088 }
5089 else
5090 insn = emit_move_insn (local, chain);
5091
5092 /* Mark the register as eliminable, similar to parameters. */
5093 if (MEM_P (chain)
5094 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
5095 set_dst_reg_note (insn, REG_EQUIV, chain, local);
5096
5097 /* If we aren't optimizing, save the static chain onto the stack. */
5098 if (!optimize)
5099 {
5100 tree saved_static_chain_decl
5101 = build_decl (DECL_SOURCE_LOCATION (parm), VAR_DECL,
5102 DECL_NAME (parm), TREE_TYPE (parm));
5103 rtx saved_static_chain_rtx
5104 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5105 SET_DECL_RTL (saved_static_chain_decl, saved_static_chain_rtx);
5106 emit_move_insn (saved_static_chain_rtx, chain);
5107 SET_DECL_VALUE_EXPR (parm, saved_static_chain_decl);
5108 DECL_HAS_VALUE_EXPR_P (parm) = 1;
5109 }
5110 }
5111
5112 /* The following was moved from init_function_start.
5113 The move was supposed to make sdb output more accurate. */
5114 /* Indicate the beginning of the function body,
5115 as opposed to parm setup. */
5116 emit_note (NOTE_INSN_FUNCTION_BEG);
5117
5118 gcc_assert (NOTE_P (get_last_insn ()));
5119
5120 parm_birth_insn = get_last_insn ();
5121
5122 /* If the function receives a non-local goto, then store the
5123 bits we need to restore the frame pointer. */
5124 if (cfun->nonlocal_goto_save_area)
5125 {
5126 tree t_save;
5127 rtx r_save;
5128
5129 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5130 gcc_assert (DECL_RTL_SET_P (var));
5131
5132 t_save = build4 (ARRAY_REF,
5133 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
5134 cfun->nonlocal_goto_save_area,
5135 integer_zero_node, NULL_TREE, NULL_TREE);
5136 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
5137 gcc_assert (GET_MODE (r_save) == Pmode);
5138
5139 emit_move_insn (r_save, hard_frame_pointer_rtx);
5140 update_nonlocal_goto_save_area ();
5141 }
5142
5143 if (crtl->profile)
5144 {
5145 #ifdef PROFILE_HOOK
5146 PROFILE_HOOK (current_function_funcdef_no);
5147 #endif
5148 }
5149
5150 /* If we are doing generic stack checking, the probe should go here. */
5151 if (flag_stack_check == GENERIC_STACK_CHECK)
5152 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
5153 }
5154 \f
5155 void
5156 pop_dummy_function (void)
5157 {
5158 pop_cfun ();
5159 in_dummy_function = false;
5160 }
5161
5162 /* Undo the effects of init_dummy_function_start. */
5163 void
5164 expand_dummy_function_end (void)
5165 {
5166 gcc_assert (in_dummy_function);
5167
5168 /* End any sequences that failed to be closed due to syntax errors. */
5169 while (in_sequence_p ())
5170 end_sequence ();
5171
5172 /* Outside function body, can't compute type's actual size
5173 until next function's body starts. */
5174
5175 free_after_parsing (cfun);
5176 free_after_compilation (cfun);
5177 pop_dummy_function ();
5178 }
5179
5180 /* Helper for diddle_return_value. */
5181
5182 void
5183 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5184 {
5185 if (! outgoing)
5186 return;
5187
5188 if (REG_P (outgoing))
5189 (*doit) (outgoing, arg);
5190 else if (GET_CODE (outgoing) == PARALLEL)
5191 {
5192 int i;
5193
5194 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5195 {
5196 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5197
5198 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5199 (*doit) (x, arg);
5200 }
5201 }
5202 }
5203
5204 /* Call DOIT for each hard register used as a return value from
5205 the current function. */
5206
5207 void
5208 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5209 {
5210 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5211 }
5212
5213 static void
5214 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5215 {
5216 emit_clobber (reg);
5217 }
5218
5219 void
5220 clobber_return_register (void)
5221 {
5222 diddle_return_value (do_clobber_return_reg, NULL);
5223
5224 /* In case we do use pseudo to return value, clobber it too. */
5225 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5226 {
5227 tree decl_result = DECL_RESULT (current_function_decl);
5228 rtx decl_rtl = DECL_RTL (decl_result);
5229 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
5230 {
5231 do_clobber_return_reg (decl_rtl, NULL);
5232 }
5233 }
5234 }
5235
5236 static void
5237 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5238 {
5239 emit_use (reg);
5240 }
5241
5242 static void
5243 use_return_register (void)
5244 {
5245 diddle_return_value (do_use_return_reg, NULL);
5246 }
5247
5248 /* Generate RTL for the end of the current function. */
5249
5250 void
5251 expand_function_end (void)
5252 {
5253 /* If arg_pointer_save_area was referenced only from a nested
5254 function, we will not have initialized it yet. Do that now. */
5255 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
5256 get_arg_pointer_save_area ();
5257
5258 /* If we are doing generic stack checking and this function makes calls,
5259 do a stack probe at the start of the function to ensure we have enough
5260 space for another stack frame. */
5261 if (flag_stack_check == GENERIC_STACK_CHECK)
5262 {
5263 rtx_insn *insn, *seq;
5264
5265 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5266 if (CALL_P (insn))
5267 {
5268 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
5269 start_sequence ();
5270 if (STACK_CHECK_MOVING_SP)
5271 anti_adjust_stack_and_probe (max_frame_size, true);
5272 else
5273 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
5274 seq = get_insns ();
5275 end_sequence ();
5276 set_insn_locations (seq, prologue_location);
5277 emit_insn_before (seq, stack_check_probe_note);
5278 break;
5279 }
5280 }
5281
5282 /* End any sequences that failed to be closed due to syntax errors. */
5283 while (in_sequence_p ())
5284 end_sequence ();
5285
5286 clear_pending_stack_adjust ();
5287 do_pending_stack_adjust ();
5288
5289 /* Output a linenumber for the end of the function.
5290 SDB depended on this. */
5291 set_curr_insn_location (input_location);
5292
5293 /* Before the return label (if any), clobber the return
5294 registers so that they are not propagated live to the rest of
5295 the function. This can only happen with functions that drop
5296 through; if there had been a return statement, there would
5297 have either been a return rtx, or a jump to the return label.
5298
5299 We delay actual code generation after the current_function_value_rtx
5300 is computed. */
5301 rtx_insn *clobber_after = get_last_insn ();
5302
5303 /* Output the label for the actual return from the function. */
5304 emit_label (return_label);
5305
5306 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
5307 {
5308 /* Let except.c know where it should emit the call to unregister
5309 the function context for sjlj exceptions. */
5310 if (flag_exceptions)
5311 sjlj_emit_function_exit_after (get_last_insn ());
5312 }
5313
5314 /* If this is an implementation of throw, do what's necessary to
5315 communicate between __builtin_eh_return and the epilogue. */
5316 expand_eh_return ();
5317
5318 /* If stack protection is enabled for this function, check the guard. */
5319 if (crtl->stack_protect_guard
5320 && targetm.stack_protect_runtime_enabled_p ()
5321 && naked_return_label == NULL_RTX)
5322 stack_protect_epilogue ();
5323
5324 /* If scalar return value was computed in a pseudo-reg, or was a named
5325 return value that got dumped to the stack, copy that to the hard
5326 return register. */
5327 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5328 {
5329 tree decl_result = DECL_RESULT (current_function_decl);
5330 rtx decl_rtl = DECL_RTL (decl_result);
5331
5332 if (REG_P (decl_rtl)
5333 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5334 : DECL_REGISTER (decl_result))
5335 {
5336 rtx real_decl_rtl = crtl->return_rtx;
5337 complex_mode cmode;
5338
5339 /* This should be set in assign_parms. */
5340 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5341
5342 /* If this is a BLKmode structure being returned in registers,
5343 then use the mode computed in expand_return. Note that if
5344 decl_rtl is memory, then its mode may have been changed,
5345 but that crtl->return_rtx has not. */
5346 if (GET_MODE (real_decl_rtl) == BLKmode)
5347 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5348
5349 /* If a non-BLKmode return value should be padded at the least
5350 significant end of the register, shift it left by the appropriate
5351 amount. BLKmode results are handled using the group load/store
5352 machinery. */
5353 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5354 && REG_P (real_decl_rtl)
5355 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5356 {
5357 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5358 REGNO (real_decl_rtl)),
5359 decl_rtl);
5360 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5361 }
5362 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5363 {
5364 /* If expand_function_start has created a PARALLEL for decl_rtl,
5365 move the result to the real return registers. Otherwise, do
5366 a group load from decl_rtl for a named return. */
5367 if (GET_CODE (decl_rtl) == PARALLEL)
5368 emit_group_move (real_decl_rtl, decl_rtl);
5369 else
5370 emit_group_load (real_decl_rtl, decl_rtl,
5371 TREE_TYPE (decl_result),
5372 int_size_in_bytes (TREE_TYPE (decl_result)));
5373 }
5374 /* In the case of complex integer modes smaller than a word, we'll
5375 need to generate some non-trivial bitfield insertions. Do that
5376 on a pseudo and not the hard register. */
5377 else if (GET_CODE (decl_rtl) == CONCAT
5378 && is_complex_int_mode (GET_MODE (decl_rtl), &cmode)
5379 && GET_MODE_BITSIZE (cmode) <= BITS_PER_WORD)
5380 {
5381 int old_generating_concat_p;
5382 rtx tmp;
5383
5384 old_generating_concat_p = generating_concat_p;
5385 generating_concat_p = 0;
5386 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5387 generating_concat_p = old_generating_concat_p;
5388
5389 emit_move_insn (tmp, decl_rtl);
5390 emit_move_insn (real_decl_rtl, tmp);
5391 }
5392 /* If a named return value dumped decl_return to memory, then
5393 we may need to re-do the PROMOTE_MODE signed/unsigned
5394 extension. */
5395 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5396 {
5397 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5398 promote_function_mode (TREE_TYPE (decl_result),
5399 GET_MODE (decl_rtl), &unsignedp,
5400 TREE_TYPE (current_function_decl), 1);
5401
5402 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5403 }
5404 else
5405 emit_move_insn (real_decl_rtl, decl_rtl);
5406 }
5407 }
5408
5409 /* If returning a structure, arrange to return the address of the value
5410 in a place where debuggers expect to find it.
5411
5412 If returning a structure PCC style,
5413 the caller also depends on this value.
5414 And cfun->returns_pcc_struct is not necessarily set. */
5415 if ((cfun->returns_struct || cfun->returns_pcc_struct)
5416 && !targetm.calls.omit_struct_return_reg)
5417 {
5418 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5419 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5420 rtx outgoing;
5421
5422 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5423 type = TREE_TYPE (type);
5424 else
5425 value_address = XEXP (value_address, 0);
5426
5427 outgoing = targetm.calls.function_value (build_pointer_type (type),
5428 current_function_decl, true);
5429
5430 /* Mark this as a function return value so integrate will delete the
5431 assignment and USE below when inlining this function. */
5432 REG_FUNCTION_VALUE_P (outgoing) = 1;
5433
5434 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5435 scalar_int_mode mode = as_a <scalar_int_mode> (GET_MODE (outgoing));
5436 value_address = convert_memory_address (mode, value_address);
5437
5438 emit_move_insn (outgoing, value_address);
5439
5440 /* Show return register used to hold result (in this case the address
5441 of the result. */
5442 crtl->return_rtx = outgoing;
5443 }
5444
5445 /* Emit the actual code to clobber return register. Don't emit
5446 it if clobber_after is a barrier, then the previous basic block
5447 certainly doesn't fall thru into the exit block. */
5448 if (!BARRIER_P (clobber_after))
5449 {
5450 start_sequence ();
5451 clobber_return_register ();
5452 rtx_insn *seq = get_insns ();
5453 end_sequence ();
5454
5455 emit_insn_after (seq, clobber_after);
5456 }
5457
5458 /* Output the label for the naked return from the function. */
5459 if (naked_return_label)
5460 emit_label (naked_return_label);
5461
5462 /* @@@ This is a kludge. We want to ensure that instructions that
5463 may trap are not moved into the epilogue by scheduling, because
5464 we don't always emit unwind information for the epilogue. */
5465 if (cfun->can_throw_non_call_exceptions
5466 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5467 emit_insn (gen_blockage ());
5468
5469 /* If stack protection is enabled for this function, check the guard. */
5470 if (crtl->stack_protect_guard
5471 && targetm.stack_protect_runtime_enabled_p ()
5472 && naked_return_label)
5473 stack_protect_epilogue ();
5474
5475 /* If we had calls to alloca, and this machine needs
5476 an accurate stack pointer to exit the function,
5477 insert some code to save and restore the stack pointer. */
5478 if (! EXIT_IGNORE_STACK
5479 && cfun->calls_alloca)
5480 {
5481 rtx tem = 0;
5482
5483 start_sequence ();
5484 emit_stack_save (SAVE_FUNCTION, &tem);
5485 rtx_insn *seq = get_insns ();
5486 end_sequence ();
5487 emit_insn_before (seq, parm_birth_insn);
5488
5489 emit_stack_restore (SAVE_FUNCTION, tem);
5490 }
5491
5492 /* ??? This should no longer be necessary since stupid is no longer with
5493 us, but there are some parts of the compiler (eg reload_combine, and
5494 sh mach_dep_reorg) that still try and compute their own lifetime info
5495 instead of using the general framework. */
5496 use_return_register ();
5497 }
5498
5499 rtx
5500 get_arg_pointer_save_area (void)
5501 {
5502 rtx ret = arg_pointer_save_area;
5503
5504 if (! ret)
5505 {
5506 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5507 arg_pointer_save_area = ret;
5508 }
5509
5510 if (! crtl->arg_pointer_save_area_init)
5511 {
5512 /* Save the arg pointer at the beginning of the function. The
5513 generated stack slot may not be a valid memory address, so we
5514 have to check it and fix it if necessary. */
5515 start_sequence ();
5516 emit_move_insn (validize_mem (copy_rtx (ret)),
5517 crtl->args.internal_arg_pointer);
5518 rtx_insn *seq = get_insns ();
5519 end_sequence ();
5520
5521 push_topmost_sequence ();
5522 emit_insn_after (seq, entry_of_function ());
5523 pop_topmost_sequence ();
5524
5525 crtl->arg_pointer_save_area_init = true;
5526 }
5527
5528 return ret;
5529 }
5530 \f
5531
5532 /* If debugging dumps are requested, dump information about how the
5533 target handled -fstack-check=clash for the prologue.
5534
5535 PROBES describes what if any probes were emitted.
5536
5537 RESIDUALS indicates if the prologue had any residual allocation
5538 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5539
5540 void
5541 dump_stack_clash_frame_info (enum stack_clash_probes probes, bool residuals)
5542 {
5543 if (!dump_file)
5544 return;
5545
5546 switch (probes)
5547 {
5548 case NO_PROBE_NO_FRAME:
5549 fprintf (dump_file,
5550 "Stack clash no probe no stack adjustment in prologue.\n");
5551 break;
5552 case NO_PROBE_SMALL_FRAME:
5553 fprintf (dump_file,
5554 "Stack clash no probe small stack adjustment in prologue.\n");
5555 break;
5556 case PROBE_INLINE:
5557 fprintf (dump_file, "Stack clash inline probes in prologue.\n");
5558 break;
5559 case PROBE_LOOP:
5560 fprintf (dump_file, "Stack clash probe loop in prologue.\n");
5561 break;
5562 }
5563
5564 if (residuals)
5565 fprintf (dump_file, "Stack clash residual allocation in prologue.\n");
5566 else
5567 fprintf (dump_file, "Stack clash no residual allocation in prologue.\n");
5568
5569 if (frame_pointer_needed)
5570 fprintf (dump_file, "Stack clash frame pointer needed.\n");
5571 else
5572 fprintf (dump_file, "Stack clash no frame pointer needed.\n");
5573
5574 if (TREE_THIS_VOLATILE (cfun->decl))
5575 fprintf (dump_file,
5576 "Stack clash noreturn prologue, assuming no implicit"
5577 " probes in caller.\n");
5578 else
5579 fprintf (dump_file,
5580 "Stack clash not noreturn prologue.\n");
5581 }
5582
5583 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5584 for the first time. */
5585
5586 static void
5587 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5588 {
5589 rtx_insn *tmp;
5590 hash_table<insn_cache_hasher> *hash = *hashp;
5591
5592 if (hash == NULL)
5593 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5594
5595 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5596 {
5597 rtx *slot = hash->find_slot (tmp, INSERT);
5598 gcc_assert (*slot == NULL);
5599 *slot = tmp;
5600 }
5601 }
5602
5603 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5604 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5605 insn, then record COPY as well. */
5606
5607 void
5608 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5609 {
5610 hash_table<insn_cache_hasher> *hash;
5611 rtx *slot;
5612
5613 hash = epilogue_insn_hash;
5614 if (!hash || !hash->find (insn))
5615 {
5616 hash = prologue_insn_hash;
5617 if (!hash || !hash->find (insn))
5618 return;
5619 }
5620
5621 slot = hash->find_slot (copy, INSERT);
5622 gcc_assert (*slot == NULL);
5623 *slot = copy;
5624 }
5625
5626 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5627 we can be running after reorg, SEQUENCE rtl is possible. */
5628
5629 static bool
5630 contains (const rtx_insn *insn, hash_table<insn_cache_hasher> *hash)
5631 {
5632 if (hash == NULL)
5633 return false;
5634
5635 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5636 {
5637 rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn));
5638 int i;
5639 for (i = seq->len () - 1; i >= 0; i--)
5640 if (hash->find (seq->element (i)))
5641 return true;
5642 return false;
5643 }
5644
5645 return hash->find (const_cast<rtx_insn *> (insn)) != NULL;
5646 }
5647
5648 int
5649 prologue_contains (const rtx_insn *insn)
5650 {
5651 return contains (insn, prologue_insn_hash);
5652 }
5653
5654 int
5655 epilogue_contains (const rtx_insn *insn)
5656 {
5657 return contains (insn, epilogue_insn_hash);
5658 }
5659
5660 int
5661 prologue_epilogue_contains (const rtx_insn *insn)
5662 {
5663 if (contains (insn, prologue_insn_hash))
5664 return 1;
5665 if (contains (insn, epilogue_insn_hash))
5666 return 1;
5667 return 0;
5668 }
5669
5670 void
5671 record_prologue_seq (rtx_insn *seq)
5672 {
5673 record_insns (seq, NULL, &prologue_insn_hash);
5674 }
5675
5676 void
5677 record_epilogue_seq (rtx_insn *seq)
5678 {
5679 record_insns (seq, NULL, &epilogue_insn_hash);
5680 }
5681
5682 /* Set JUMP_LABEL for a return insn. */
5683
5684 void
5685 set_return_jump_label (rtx_insn *returnjump)
5686 {
5687 rtx pat = PATTERN (returnjump);
5688 if (GET_CODE (pat) == PARALLEL)
5689 pat = XVECEXP (pat, 0, 0);
5690 if (ANY_RETURN_P (pat))
5691 JUMP_LABEL (returnjump) = pat;
5692 else
5693 JUMP_LABEL (returnjump) = ret_rtx;
5694 }
5695
5696 /* Return a sequence to be used as the split prologue for the current
5697 function, or NULL. */
5698
5699 static rtx_insn *
5700 make_split_prologue_seq (void)
5701 {
5702 if (!flag_split_stack
5703 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl)))
5704 return NULL;
5705
5706 start_sequence ();
5707 emit_insn (targetm.gen_split_stack_prologue ());
5708 rtx_insn *seq = get_insns ();
5709 end_sequence ();
5710
5711 record_insns (seq, NULL, &prologue_insn_hash);
5712 set_insn_locations (seq, prologue_location);
5713
5714 return seq;
5715 }
5716
5717 /* Return a sequence to be used as the prologue for the current function,
5718 or NULL. */
5719
5720 static rtx_insn *
5721 make_prologue_seq (void)
5722 {
5723 if (!targetm.have_prologue ())
5724 return NULL;
5725
5726 start_sequence ();
5727 rtx_insn *seq = targetm.gen_prologue ();
5728 emit_insn (seq);
5729
5730 /* Insert an explicit USE for the frame pointer
5731 if the profiling is on and the frame pointer is required. */
5732 if (crtl->profile && frame_pointer_needed)
5733 emit_use (hard_frame_pointer_rtx);
5734
5735 /* Retain a map of the prologue insns. */
5736 record_insns (seq, NULL, &prologue_insn_hash);
5737 emit_note (NOTE_INSN_PROLOGUE_END);
5738
5739 /* Ensure that instructions are not moved into the prologue when
5740 profiling is on. The call to the profiling routine can be
5741 emitted within the live range of a call-clobbered register. */
5742 if (!targetm.profile_before_prologue () && crtl->profile)
5743 emit_insn (gen_blockage ());
5744
5745 seq = get_insns ();
5746 end_sequence ();
5747 set_insn_locations (seq, prologue_location);
5748
5749 return seq;
5750 }
5751
5752 /* Return a sequence to be used as the epilogue for the current function,
5753 or NULL. */
5754
5755 static rtx_insn *
5756 make_epilogue_seq (void)
5757 {
5758 if (!targetm.have_epilogue ())
5759 return NULL;
5760
5761 start_sequence ();
5762 emit_note (NOTE_INSN_EPILOGUE_BEG);
5763 rtx_insn *seq = targetm.gen_epilogue ();
5764 if (seq)
5765 emit_jump_insn (seq);
5766
5767 /* Retain a map of the epilogue insns. */
5768 record_insns (seq, NULL, &epilogue_insn_hash);
5769 set_insn_locations (seq, epilogue_location);
5770
5771 seq = get_insns ();
5772 rtx_insn *returnjump = get_last_insn ();
5773 end_sequence ();
5774
5775 if (JUMP_P (returnjump))
5776 set_return_jump_label (returnjump);
5777
5778 return seq;
5779 }
5780
5781
5782 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5783 this into place with notes indicating where the prologue ends and where
5784 the epilogue begins. Update the basic block information when possible.
5785
5786 Notes on epilogue placement:
5787 There are several kinds of edges to the exit block:
5788 * a single fallthru edge from LAST_BB
5789 * possibly, edges from blocks containing sibcalls
5790 * possibly, fake edges from infinite loops
5791
5792 The epilogue is always emitted on the fallthru edge from the last basic
5793 block in the function, LAST_BB, into the exit block.
5794
5795 If LAST_BB is empty except for a label, it is the target of every
5796 other basic block in the function that ends in a return. If a
5797 target has a return or simple_return pattern (possibly with
5798 conditional variants), these basic blocks can be changed so that a
5799 return insn is emitted into them, and their target is adjusted to
5800 the real exit block.
5801
5802 Notes on shrink wrapping: We implement a fairly conservative
5803 version of shrink-wrapping rather than the textbook one. We only
5804 generate a single prologue and a single epilogue. This is
5805 sufficient to catch a number of interesting cases involving early
5806 exits.
5807
5808 First, we identify the blocks that require the prologue to occur before
5809 them. These are the ones that modify a call-saved register, or reference
5810 any of the stack or frame pointer registers. To simplify things, we then
5811 mark everything reachable from these blocks as also requiring a prologue.
5812 This takes care of loops automatically, and avoids the need to examine
5813 whether MEMs reference the frame, since it is sufficient to check for
5814 occurrences of the stack or frame pointer.
5815
5816 We then compute the set of blocks for which the need for a prologue
5817 is anticipatable (borrowing terminology from the shrink-wrapping
5818 description in Muchnick's book). These are the blocks which either
5819 require a prologue themselves, or those that have only successors
5820 where the prologue is anticipatable. The prologue needs to be
5821 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5822 is not. For the moment, we ensure that only one such edge exists.
5823
5824 The epilogue is placed as described above, but we make a
5825 distinction between inserting return and simple_return patterns
5826 when modifying other blocks that end in a return. Blocks that end
5827 in a sibcall omit the sibcall_epilogue if the block is not in
5828 ANTIC. */
5829
5830 void
5831 thread_prologue_and_epilogue_insns (void)
5832 {
5833 df_analyze ();
5834
5835 /* Can't deal with multiple successors of the entry block at the
5836 moment. Function should always have at least one entry
5837 point. */
5838 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
5839
5840 edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5841 edge orig_entry_edge = entry_edge;
5842
5843 rtx_insn *split_prologue_seq = make_split_prologue_seq ();
5844 rtx_insn *prologue_seq = make_prologue_seq ();
5845 rtx_insn *epilogue_seq = make_epilogue_seq ();
5846
5847 /* Try to perform a kind of shrink-wrapping, making sure the
5848 prologue/epilogue is emitted only around those parts of the
5849 function that require it. */
5850 try_shrink_wrapping (&entry_edge, prologue_seq);
5851
5852 /* If the target can handle splitting the prologue/epilogue into separate
5853 components, try to shrink-wrap these components separately. */
5854 try_shrink_wrapping_separate (entry_edge->dest);
5855
5856 /* If that did anything for any component we now need the generate the
5857 "main" prologue again. Because some targets require some of these
5858 to be called in a specific order (i386 requires the split prologue
5859 to be first, for example), we create all three sequences again here.
5860 If this does not work for some target, that target should not enable
5861 separate shrink-wrapping. */
5862 if (crtl->shrink_wrapped_separate)
5863 {
5864 split_prologue_seq = make_split_prologue_seq ();
5865 prologue_seq = make_prologue_seq ();
5866 epilogue_seq = make_epilogue_seq ();
5867 }
5868
5869 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
5870
5871 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5872 this marker for the splits of EH_RETURN patterns, and nothing else
5873 uses the flag in the meantime. */
5874 epilogue_completed = 1;
5875
5876 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5877 some targets, these get split to a special version of the epilogue
5878 code. In order to be able to properly annotate these with unwind
5879 info, try to split them now. If we get a valid split, drop an
5880 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5881 edge e;
5882 edge_iterator ei;
5883 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5884 {
5885 rtx_insn *prev, *last, *trial;
5886
5887 if (e->flags & EDGE_FALLTHRU)
5888 continue;
5889 last = BB_END (e->src);
5890 if (!eh_returnjump_p (last))
5891 continue;
5892
5893 prev = PREV_INSN (last);
5894 trial = try_split (PATTERN (last), last, 1);
5895 if (trial == last)
5896 continue;
5897
5898 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5899 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5900 }
5901
5902 edge exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
5903
5904 if (exit_fallthru_edge)
5905 {
5906 if (epilogue_seq)
5907 {
5908 insert_insn_on_edge (epilogue_seq, exit_fallthru_edge);
5909 commit_edge_insertions ();
5910
5911 /* The epilogue insns we inserted may cause the exit edge to no longer
5912 be fallthru. */
5913 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5914 {
5915 if (((e->flags & EDGE_FALLTHRU) != 0)
5916 && returnjump_p (BB_END (e->src)))
5917 e->flags &= ~EDGE_FALLTHRU;
5918 }
5919 }
5920 else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
5921 {
5922 /* We have a fall-through edge to the exit block, the source is not
5923 at the end of the function, and there will be an assembler epilogue
5924 at the end of the function.
5925 We can't use force_nonfallthru here, because that would try to
5926 use return. Inserting a jump 'by hand' is extremely messy, so
5927 we take advantage of cfg_layout_finalize using
5928 fixup_fallthru_exit_predecessor. */
5929 cfg_layout_initialize (0);
5930 basic_block cur_bb;
5931 FOR_EACH_BB_FN (cur_bb, cfun)
5932 if (cur_bb->index >= NUM_FIXED_BLOCKS
5933 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5934 cur_bb->aux = cur_bb->next_bb;
5935 cfg_layout_finalize ();
5936 }
5937 }
5938
5939 /* Insert the prologue. */
5940
5941 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5942
5943 if (split_prologue_seq || prologue_seq)
5944 {
5945 rtx_insn *split_prologue_insn = split_prologue_seq;
5946 if (split_prologue_seq)
5947 {
5948 while (split_prologue_insn && !NONDEBUG_INSN_P (split_prologue_insn))
5949 split_prologue_insn = NEXT_INSN (split_prologue_insn);
5950 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
5951 }
5952
5953 rtx_insn *prologue_insn = prologue_seq;
5954 if (prologue_seq)
5955 {
5956 while (prologue_insn && !NONDEBUG_INSN_P (prologue_insn))
5957 prologue_insn = NEXT_INSN (prologue_insn);
5958 insert_insn_on_edge (prologue_seq, entry_edge);
5959 }
5960
5961 commit_edge_insertions ();
5962
5963 /* Look for basic blocks within the prologue insns. */
5964 if (split_prologue_insn
5965 && BLOCK_FOR_INSN (split_prologue_insn) == NULL)
5966 split_prologue_insn = NULL;
5967 if (prologue_insn
5968 && BLOCK_FOR_INSN (prologue_insn) == NULL)
5969 prologue_insn = NULL;
5970 if (split_prologue_insn || prologue_insn)
5971 {
5972 auto_sbitmap blocks (last_basic_block_for_fn (cfun));
5973 bitmap_clear (blocks);
5974 if (split_prologue_insn)
5975 bitmap_set_bit (blocks,
5976 BLOCK_FOR_INSN (split_prologue_insn)->index);
5977 if (prologue_insn)
5978 bitmap_set_bit (blocks, BLOCK_FOR_INSN (prologue_insn)->index);
5979 find_many_sub_basic_blocks (blocks);
5980 }
5981 }
5982
5983 default_rtl_profile ();
5984
5985 /* Emit sibling epilogues before any sibling call sites. */
5986 for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
5987 (e = ei_safe_edge (ei));
5988 ei_next (&ei))
5989 {
5990 /* Skip those already handled, the ones that run without prologue. */
5991 if (e->flags & EDGE_IGNORE)
5992 {
5993 e->flags &= ~EDGE_IGNORE;
5994 continue;
5995 }
5996
5997 rtx_insn *insn = BB_END (e->src);
5998
5999 if (!(CALL_P (insn) && SIBLING_CALL_P (insn)))
6000 continue;
6001
6002 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6003 {
6004 start_sequence ();
6005 emit_note (NOTE_INSN_EPILOGUE_BEG);
6006 emit_insn (ep_seq);
6007 rtx_insn *seq = get_insns ();
6008 end_sequence ();
6009
6010 /* Retain a map of the epilogue insns. Used in life analysis to
6011 avoid getting rid of sibcall epilogue insns. Do this before we
6012 actually emit the sequence. */
6013 record_insns (seq, NULL, &epilogue_insn_hash);
6014 set_insn_locations (seq, epilogue_location);
6015
6016 emit_insn_before (seq, insn);
6017 }
6018 }
6019
6020 if (epilogue_seq)
6021 {
6022 rtx_insn *insn, *next;
6023
6024 /* Similarly, move any line notes that appear after the epilogue.
6025 There is no need, however, to be quite so anal about the existence
6026 of such a note. Also possibly move
6027 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6028 info generation. */
6029 for (insn = epilogue_seq; insn; insn = next)
6030 {
6031 next = NEXT_INSN (insn);
6032 if (NOTE_P (insn)
6033 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6034 reorder_insns (insn, insn, PREV_INSN (epilogue_seq));
6035 }
6036 }
6037
6038 /* Threading the prologue and epilogue changes the artificial refs
6039 in the entry and exit blocks. */
6040 epilogue_completed = 1;
6041 df_update_entry_exit_and_calls ();
6042 }
6043
6044 /* Reposition the prologue-end and epilogue-begin notes after
6045 instruction scheduling. */
6046
6047 void
6048 reposition_prologue_and_epilogue_notes (void)
6049 {
6050 if (!targetm.have_prologue ()
6051 && !targetm.have_epilogue ()
6052 && !targetm.have_sibcall_epilogue ())
6053 return;
6054
6055 /* Since the hash table is created on demand, the fact that it is
6056 non-null is a signal that it is non-empty. */
6057 if (prologue_insn_hash != NULL)
6058 {
6059 size_t len = prologue_insn_hash->elements ();
6060 rtx_insn *insn, *last = NULL, *note = NULL;
6061
6062 /* Scan from the beginning until we reach the last prologue insn. */
6063 /* ??? While we do have the CFG intact, there are two problems:
6064 (1) The prologue can contain loops (typically probing the stack),
6065 which means that the end of the prologue isn't in the first bb.
6066 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6067 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6068 {
6069 if (NOTE_P (insn))
6070 {
6071 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6072 note = insn;
6073 }
6074 else if (contains (insn, prologue_insn_hash))
6075 {
6076 last = insn;
6077 if (--len == 0)
6078 break;
6079 }
6080 }
6081
6082 if (last)
6083 {
6084 if (note == NULL)
6085 {
6086 /* Scan forward looking for the PROLOGUE_END note. It should
6087 be right at the beginning of the block, possibly with other
6088 insn notes that got moved there. */
6089 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6090 {
6091 if (NOTE_P (note)
6092 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6093 break;
6094 }
6095 }
6096
6097 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6098 if (LABEL_P (last))
6099 last = NEXT_INSN (last);
6100 reorder_insns (note, note, last);
6101 }
6102 }
6103
6104 if (epilogue_insn_hash != NULL)
6105 {
6106 edge_iterator ei;
6107 edge e;
6108
6109 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6110 {
6111 rtx_insn *insn, *first = NULL, *note = NULL;
6112 basic_block bb = e->src;
6113
6114 /* Scan from the beginning until we reach the first epilogue insn. */
6115 FOR_BB_INSNS (bb, insn)
6116 {
6117 if (NOTE_P (insn))
6118 {
6119 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6120 {
6121 note = insn;
6122 if (first != NULL)
6123 break;
6124 }
6125 }
6126 else if (first == NULL && contains (insn, epilogue_insn_hash))
6127 {
6128 first = insn;
6129 if (note != NULL)
6130 break;
6131 }
6132 }
6133
6134 if (note)
6135 {
6136 /* If the function has a single basic block, and no real
6137 epilogue insns (e.g. sibcall with no cleanup), the
6138 epilogue note can get scheduled before the prologue
6139 note. If we have frame related prologue insns, having
6140 them scanned during the epilogue will result in a crash.
6141 In this case re-order the epilogue note to just before
6142 the last insn in the block. */
6143 if (first == NULL)
6144 first = BB_END (bb);
6145
6146 if (PREV_INSN (first) != note)
6147 reorder_insns (note, note, PREV_INSN (first));
6148 }
6149 }
6150 }
6151 }
6152
6153 /* Returns the name of function declared by FNDECL. */
6154 const char *
6155 fndecl_name (tree fndecl)
6156 {
6157 if (fndecl == NULL)
6158 return "(nofn)";
6159 return lang_hooks.decl_printable_name (fndecl, 1);
6160 }
6161
6162 /* Returns the name of function FN. */
6163 const char *
6164 function_name (struct function *fn)
6165 {
6166 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6167 return fndecl_name (fndecl);
6168 }
6169
6170 /* Returns the name of the current function. */
6171 const char *
6172 current_function_name (void)
6173 {
6174 return function_name (cfun);
6175 }
6176 \f
6177
6178 static unsigned int
6179 rest_of_handle_check_leaf_regs (void)
6180 {
6181 #ifdef LEAF_REGISTERS
6182 crtl->uses_only_leaf_regs
6183 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6184 #endif
6185 return 0;
6186 }
6187
6188 /* Insert a TYPE into the used types hash table of CFUN. */
6189
6190 static void
6191 used_types_insert_helper (tree type, struct function *func)
6192 {
6193 if (type != NULL && func != NULL)
6194 {
6195 if (func->used_types_hash == NULL)
6196 func->used_types_hash = hash_set<tree>::create_ggc (37);
6197
6198 func->used_types_hash->add (type);
6199 }
6200 }
6201
6202 /* Given a type, insert it into the used hash table in cfun. */
6203 void
6204 used_types_insert (tree t)
6205 {
6206 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6207 if (TYPE_NAME (t))
6208 break;
6209 else
6210 t = TREE_TYPE (t);
6211 if (TREE_CODE (t) == ERROR_MARK)
6212 return;
6213 if (TYPE_NAME (t) == NULL_TREE
6214 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6215 t = TYPE_MAIN_VARIANT (t);
6216 if (debug_info_level > DINFO_LEVEL_NONE)
6217 {
6218 if (cfun)
6219 used_types_insert_helper (t, cfun);
6220 else
6221 {
6222 /* So this might be a type referenced by a global variable.
6223 Record that type so that we can later decide to emit its
6224 debug information. */
6225 vec_safe_push (types_used_by_cur_var_decl, t);
6226 }
6227 }
6228 }
6229
6230 /* Helper to Hash a struct types_used_by_vars_entry. */
6231
6232 static hashval_t
6233 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6234 {
6235 gcc_assert (entry && entry->var_decl && entry->type);
6236
6237 return iterative_hash_object (entry->type,
6238 iterative_hash_object (entry->var_decl, 0));
6239 }
6240
6241 /* Hash function of the types_used_by_vars_entry hash table. */
6242
6243 hashval_t
6244 used_type_hasher::hash (types_used_by_vars_entry *entry)
6245 {
6246 return hash_types_used_by_vars_entry (entry);
6247 }
6248
6249 /*Equality function of the types_used_by_vars_entry hash table. */
6250
6251 bool
6252 used_type_hasher::equal (types_used_by_vars_entry *e1,
6253 types_used_by_vars_entry *e2)
6254 {
6255 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6256 }
6257
6258 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6259
6260 void
6261 types_used_by_var_decl_insert (tree type, tree var_decl)
6262 {
6263 if (type != NULL && var_decl != NULL)
6264 {
6265 types_used_by_vars_entry **slot;
6266 struct types_used_by_vars_entry e;
6267 e.var_decl = var_decl;
6268 e.type = type;
6269 if (types_used_by_vars_hash == NULL)
6270 types_used_by_vars_hash
6271 = hash_table<used_type_hasher>::create_ggc (37);
6272
6273 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6274 if (*slot == NULL)
6275 {
6276 struct types_used_by_vars_entry *entry;
6277 entry = ggc_alloc<types_used_by_vars_entry> ();
6278 entry->type = type;
6279 entry->var_decl = var_decl;
6280 *slot = entry;
6281 }
6282 }
6283 }
6284
6285 namespace {
6286
6287 const pass_data pass_data_leaf_regs =
6288 {
6289 RTL_PASS, /* type */
6290 "*leaf_regs", /* name */
6291 OPTGROUP_NONE, /* optinfo_flags */
6292 TV_NONE, /* tv_id */
6293 0, /* properties_required */
6294 0, /* properties_provided */
6295 0, /* properties_destroyed */
6296 0, /* todo_flags_start */
6297 0, /* todo_flags_finish */
6298 };
6299
6300 class pass_leaf_regs : public rtl_opt_pass
6301 {
6302 public:
6303 pass_leaf_regs (gcc::context *ctxt)
6304 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6305 {}
6306
6307 /* opt_pass methods: */
6308 virtual unsigned int execute (function *)
6309 {
6310 return rest_of_handle_check_leaf_regs ();
6311 }
6312
6313 }; // class pass_leaf_regs
6314
6315 } // anon namespace
6316
6317 rtl_opt_pass *
6318 make_pass_leaf_regs (gcc::context *ctxt)
6319 {
6320 return new pass_leaf_regs (ctxt);
6321 }
6322
6323 static unsigned int
6324 rest_of_handle_thread_prologue_and_epilogue (void)
6325 {
6326 /* prepare_shrink_wrap is sensitive to the block structure of the control
6327 flow graph, so clean it up first. */
6328 if (optimize)
6329 cleanup_cfg (0);
6330
6331 /* On some machines, the prologue and epilogue code, or parts thereof,
6332 can be represented as RTL. Doing so lets us schedule insns between
6333 it and the rest of the code and also allows delayed branch
6334 scheduling to operate in the epilogue. */
6335 thread_prologue_and_epilogue_insns ();
6336
6337 /* Some non-cold blocks may now be only reachable from cold blocks.
6338 Fix that up. */
6339 fixup_partitions ();
6340
6341 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6342 see PR57320. */
6343 cleanup_cfg (optimize ? CLEANUP_EXPENSIVE : 0);
6344
6345 /* The stack usage info is finalized during prologue expansion. */
6346 if (flag_stack_usage_info)
6347 output_stack_usage ();
6348
6349 return 0;
6350 }
6351
6352 namespace {
6353
6354 const pass_data pass_data_thread_prologue_and_epilogue =
6355 {
6356 RTL_PASS, /* type */
6357 "pro_and_epilogue", /* name */
6358 OPTGROUP_NONE, /* optinfo_flags */
6359 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6360 0, /* properties_required */
6361 0, /* properties_provided */
6362 0, /* properties_destroyed */
6363 0, /* todo_flags_start */
6364 ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
6365 };
6366
6367 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6368 {
6369 public:
6370 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6371 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6372 {}
6373
6374 /* opt_pass methods: */
6375 virtual unsigned int execute (function *)
6376 {
6377 return rest_of_handle_thread_prologue_and_epilogue ();
6378 }
6379
6380 }; // class pass_thread_prologue_and_epilogue
6381
6382 } // anon namespace
6383
6384 rtl_opt_pass *
6385 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6386 {
6387 return new pass_thread_prologue_and_epilogue (ctxt);
6388 }
6389 \f
6390
6391 /* If CONSTRAINT is a matching constraint, then return its number.
6392 Otherwise, return -1. */
6393
6394 static int
6395 matching_constraint_num (const char *constraint)
6396 {
6397 if (*constraint == '%')
6398 constraint++;
6399
6400 if (IN_RANGE (*constraint, '0', '9'))
6401 return strtoul (constraint, NULL, 10);
6402
6403 return -1;
6404 }
6405
6406 /* This mini-pass fixes fall-out from SSA in asm statements that have
6407 in-out constraints. Say you start with
6408
6409 orig = inout;
6410 asm ("": "+mr" (inout));
6411 use (orig);
6412
6413 which is transformed very early to use explicit output and match operands:
6414
6415 orig = inout;
6416 asm ("": "=mr" (inout) : "0" (inout));
6417 use (orig);
6418
6419 Or, after SSA and copyprop,
6420
6421 asm ("": "=mr" (inout_2) : "0" (inout_1));
6422 use (inout_1);
6423
6424 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6425 they represent two separate values, so they will get different pseudo
6426 registers during expansion. Then, since the two operands need to match
6427 per the constraints, but use different pseudo registers, reload can
6428 only register a reload for these operands. But reloads can only be
6429 satisfied by hardregs, not by memory, so we need a register for this
6430 reload, just because we are presented with non-matching operands.
6431 So, even though we allow memory for this operand, no memory can be
6432 used for it, just because the two operands don't match. This can
6433 cause reload failures on register-starved targets.
6434
6435 So it's a symptom of reload not being able to use memory for reloads
6436 or, alternatively it's also a symptom of both operands not coming into
6437 reload as matching (in which case the pseudo could go to memory just
6438 fine, as the alternative allows it, and no reload would be necessary).
6439 We fix the latter problem here, by transforming
6440
6441 asm ("": "=mr" (inout_2) : "0" (inout_1));
6442
6443 back to
6444
6445 inout_2 = inout_1;
6446 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6447
6448 static void
6449 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
6450 {
6451 int i;
6452 bool changed = false;
6453 rtx op = SET_SRC (p_sets[0]);
6454 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6455 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6456 bool *output_matched = XALLOCAVEC (bool, noutputs);
6457
6458 memset (output_matched, 0, noutputs * sizeof (bool));
6459 for (i = 0; i < ninputs; i++)
6460 {
6461 rtx input, output;
6462 rtx_insn *insns;
6463 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6464 int match, j;
6465
6466 match = matching_constraint_num (constraint);
6467 if (match < 0)
6468 continue;
6469
6470 gcc_assert (match < noutputs);
6471 output = SET_DEST (p_sets[match]);
6472 input = RTVEC_ELT (inputs, i);
6473 /* Only do the transformation for pseudos. */
6474 if (! REG_P (output)
6475 || rtx_equal_p (output, input)
6476 || !(REG_P (input) || SUBREG_P (input)
6477 || MEM_P (input) || CONSTANT_P (input))
6478 || !general_operand (input, GET_MODE (output)))
6479 continue;
6480
6481 /* We can't do anything if the output is also used as input,
6482 as we're going to overwrite it. */
6483 for (j = 0; j < ninputs; j++)
6484 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6485 break;
6486 if (j != ninputs)
6487 continue;
6488
6489 /* Avoid changing the same input several times. For
6490 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6491 only change it once (to out1), rather than changing it
6492 first to out1 and afterwards to out2. */
6493 if (i > 0)
6494 {
6495 for (j = 0; j < noutputs; j++)
6496 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6497 break;
6498 if (j != noutputs)
6499 continue;
6500 }
6501 output_matched[match] = true;
6502
6503 start_sequence ();
6504 emit_move_insn (output, copy_rtx (input));
6505 insns = get_insns ();
6506 end_sequence ();
6507 emit_insn_before (insns, insn);
6508
6509 constraint = ASM_OPERANDS_OUTPUT_CONSTRAINT(SET_SRC(p_sets[match]));
6510 bool early_clobber_p = strchr (constraint, '&') != NULL;
6511
6512 /* Now replace all mentions of the input with output. We can't
6513 just replace the occurrence in inputs[i], as the register might
6514 also be used in some other input (or even in an address of an
6515 output), which would mean possibly increasing the number of
6516 inputs by one (namely 'output' in addition), which might pose
6517 a too complicated problem for reload to solve. E.g. this situation:
6518
6519 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6520
6521 Here 'input' is used in two occurrences as input (once for the
6522 input operand, once for the address in the second output operand).
6523 If we would replace only the occurrence of the input operand (to
6524 make the matching) we would be left with this:
6525
6526 output = input
6527 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6528
6529 Now we suddenly have two different input values (containing the same
6530 value, but different pseudos) where we formerly had only one.
6531 With more complicated asms this might lead to reload failures
6532 which wouldn't have happen without this pass. So, iterate over
6533 all operands and replace all occurrences of the register used.
6534
6535 However, if one or more of the 'input' uses have a non-matching
6536 constraint and the matched output operand is an early clobber
6537 operand, then do not replace the input operand, since by definition
6538 it conflicts with the output operand and cannot share the same
6539 register. See PR89313 for details. */
6540
6541 for (j = 0; j < noutputs; j++)
6542 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6543 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6544 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6545 input, output);
6546 for (j = 0; j < ninputs; j++)
6547 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6548 {
6549 if (!early_clobber_p
6550 || match == matching_constraint_num
6551 (ASM_OPERANDS_INPUT_CONSTRAINT (op, j)))
6552 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6553 input, output);
6554 }
6555
6556 changed = true;
6557 }
6558
6559 if (changed)
6560 df_insn_rescan (insn);
6561 }
6562
6563 /* Add the decl D to the local_decls list of FUN. */
6564
6565 void
6566 add_local_decl (struct function *fun, tree d)
6567 {
6568 gcc_assert (VAR_P (d));
6569 vec_safe_push (fun->local_decls, d);
6570 }
6571
6572 namespace {
6573
6574 const pass_data pass_data_match_asm_constraints =
6575 {
6576 RTL_PASS, /* type */
6577 "asmcons", /* name */
6578 OPTGROUP_NONE, /* optinfo_flags */
6579 TV_NONE, /* tv_id */
6580 0, /* properties_required */
6581 0, /* properties_provided */
6582 0, /* properties_destroyed */
6583 0, /* todo_flags_start */
6584 0, /* todo_flags_finish */
6585 };
6586
6587 class pass_match_asm_constraints : public rtl_opt_pass
6588 {
6589 public:
6590 pass_match_asm_constraints (gcc::context *ctxt)
6591 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6592 {}
6593
6594 /* opt_pass methods: */
6595 virtual unsigned int execute (function *);
6596
6597 }; // class pass_match_asm_constraints
6598
6599 unsigned
6600 pass_match_asm_constraints::execute (function *fun)
6601 {
6602 basic_block bb;
6603 rtx_insn *insn;
6604 rtx pat, *p_sets;
6605 int noutputs;
6606
6607 if (!crtl->has_asm_statement)
6608 return 0;
6609
6610 df_set_flags (DF_DEFER_INSN_RESCAN);
6611 FOR_EACH_BB_FN (bb, fun)
6612 {
6613 FOR_BB_INSNS (bb, insn)
6614 {
6615 if (!INSN_P (insn))
6616 continue;
6617
6618 pat = PATTERN (insn);
6619 if (GET_CODE (pat) == PARALLEL)
6620 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6621 else if (GET_CODE (pat) == SET)
6622 p_sets = &PATTERN (insn), noutputs = 1;
6623 else
6624 continue;
6625
6626 if (GET_CODE (*p_sets) == SET
6627 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6628 match_asm_constraints_1 (insn, p_sets, noutputs);
6629 }
6630 }
6631
6632 return TODO_df_finish;
6633 }
6634
6635 } // anon namespace
6636
6637 rtl_opt_pass *
6638 make_pass_match_asm_constraints (gcc::context *ctxt)
6639 {
6640 return new pass_match_asm_constraints (ctxt);
6641 }
6642
6643
6644 #include "gt-function.h"