poly_int: SUBREG_BYTE
[gcc.git] / gcc / function.c
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2017 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-chkp.h"
77 #include "rtl-chkp.h"
78 #include "tree-dfa.h"
79 #include "tree-ssa.h"
80 #include "stringpool.h"
81 #include "attribs.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 HOST_WIDE_INT
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 (HOST_WIDE_INT offset, tree func)
236 {
237 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
238
239 if (size > (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 error_at (DECL_SOURCE_LOCATION (func),
244 "total size of local objects too large");
245 return TRUE;
246 }
247
248 return FALSE;
249 }
250
251 /* Return the minimum spill slot alignment for a register of mode MODE. */
252
253 unsigned int
254 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED)
255 {
256 return STACK_SLOT_ALIGNMENT (NULL_TREE, mode, GET_MODE_ALIGNMENT (mode));
257 }
258
259 /* Return stack slot alignment in bits for TYPE and MODE. */
260
261 static unsigned int
262 get_stack_local_alignment (tree type, machine_mode mode)
263 {
264 unsigned int alignment;
265
266 if (mode == BLKmode)
267 alignment = BIGGEST_ALIGNMENT;
268 else
269 alignment = GET_MODE_ALIGNMENT (mode);
270
271 /* Allow the frond-end to (possibly) increase the alignment of this
272 stack slot. */
273 if (! type)
274 type = lang_hooks.types.type_for_mode (mode, 0);
275
276 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
277 }
278
279 /* Determine whether it is possible to fit a stack slot of size SIZE and
280 alignment ALIGNMENT into an area in the stack frame that starts at
281 frame offset START and has a length of LENGTH. If so, store the frame
282 offset to be used for the stack slot in *POFFSET and return true;
283 return false otherwise. This function will extend the frame size when
284 given a start/length pair that lies at the end of the frame. */
285
286 static bool
287 try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
288 HOST_WIDE_INT size, unsigned int alignment,
289 HOST_WIDE_INT *poffset)
290 {
291 HOST_WIDE_INT this_frame_offset;
292 int frame_off, frame_alignment, frame_phase;
293
294 /* Calculate how many bytes the start of local variables is off from
295 stack alignment. */
296 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
297 frame_off = targetm.starting_frame_offset () % frame_alignment;
298 frame_phase = frame_off ? frame_alignment - frame_off : 0;
299
300 /* Round the frame offset to the specified alignment. */
301
302 /* We must be careful here, since FRAME_OFFSET might be negative and
303 division with a negative dividend isn't as well defined as we might
304 like. So we instead assume that ALIGNMENT is a power of two and
305 use logical operations which are unambiguous. */
306 if (FRAME_GROWS_DOWNWARD)
307 this_frame_offset
308 = (FLOOR_ROUND (start + length - size - frame_phase,
309 (unsigned HOST_WIDE_INT) alignment)
310 + frame_phase);
311 else
312 this_frame_offset
313 = (CEIL_ROUND (start - frame_phase,
314 (unsigned HOST_WIDE_INT) alignment)
315 + frame_phase);
316
317 /* See if it fits. If this space is at the edge of the frame,
318 consider extending the frame to make it fit. Our caller relies on
319 this when allocating a new slot. */
320 if (frame_offset == start && this_frame_offset < frame_offset)
321 frame_offset = this_frame_offset;
322 else if (this_frame_offset < start)
323 return false;
324 else if (start + length == frame_offset
325 && this_frame_offset + size > start + length)
326 frame_offset = this_frame_offset + size;
327 else if (this_frame_offset + size > start + length)
328 return false;
329
330 *poffset = this_frame_offset;
331 return true;
332 }
333
334 /* Create a new frame_space structure describing free space in the stack
335 frame beginning at START and ending at END, and chain it into the
336 function's frame_space_list. */
337
338 static void
339 add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
340 {
341 struct frame_space *space = ggc_alloc<frame_space> ();
342 space->next = crtl->frame_space_list;
343 crtl->frame_space_list = space;
344 space->start = start;
345 space->length = end - start;
346 }
347
348 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
349 with machine mode MODE.
350
351 ALIGN controls the amount of alignment for the address of the slot:
352 0 means according to MODE,
353 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
354 -2 means use BITS_PER_UNIT,
355 positive specifies alignment boundary in bits.
356
357 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
358 alignment and ASLK_RECORD_PAD bit set if we should remember
359 extra space we allocated for alignment purposes. When we are
360 called from assign_stack_temp_for_type, it is not set so we don't
361 track the same stack slot in two independent lists.
362
363 We do not round to stack_boundary here. */
364
365 rtx
366 assign_stack_local_1 (machine_mode mode, HOST_WIDE_INT size,
367 int align, int kind)
368 {
369 rtx x, addr;
370 int bigend_correction = 0;
371 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
372 unsigned int alignment, alignment_in_bits;
373
374 if (align == 0)
375 {
376 alignment = get_stack_local_alignment (NULL, mode);
377 alignment /= BITS_PER_UNIT;
378 }
379 else if (align == -1)
380 {
381 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
382 size = CEIL_ROUND (size, alignment);
383 }
384 else if (align == -2)
385 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
386 else
387 alignment = align / BITS_PER_UNIT;
388
389 alignment_in_bits = alignment * BITS_PER_UNIT;
390
391 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
392 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
393 {
394 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
395 alignment = alignment_in_bits / BITS_PER_UNIT;
396 }
397
398 if (SUPPORTS_STACK_ALIGNMENT)
399 {
400 if (crtl->stack_alignment_estimated < alignment_in_bits)
401 {
402 if (!crtl->stack_realign_processed)
403 crtl->stack_alignment_estimated = alignment_in_bits;
404 else
405 {
406 /* If stack is realigned and stack alignment value
407 hasn't been finalized, it is OK not to increase
408 stack_alignment_estimated. The bigger alignment
409 requirement is recorded in stack_alignment_needed
410 below. */
411 gcc_assert (!crtl->stack_realign_finalized);
412 if (!crtl->stack_realign_needed)
413 {
414 /* It is OK to reduce the alignment as long as the
415 requested size is 0 or the estimated stack
416 alignment >= mode alignment. */
417 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
418 || size == 0
419 || (crtl->stack_alignment_estimated
420 >= GET_MODE_ALIGNMENT (mode)));
421 alignment_in_bits = crtl->stack_alignment_estimated;
422 alignment = alignment_in_bits / BITS_PER_UNIT;
423 }
424 }
425 }
426 }
427
428 if (crtl->stack_alignment_needed < alignment_in_bits)
429 crtl->stack_alignment_needed = alignment_in_bits;
430 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
431 crtl->max_used_stack_slot_alignment = alignment_in_bits;
432
433 if (mode != BLKmode || size != 0)
434 {
435 if (kind & ASLK_RECORD_PAD)
436 {
437 struct frame_space **psp;
438
439 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
440 {
441 struct frame_space *space = *psp;
442 if (!try_fit_stack_local (space->start, space->length, size,
443 alignment, &slot_offset))
444 continue;
445 *psp = space->next;
446 if (slot_offset > space->start)
447 add_frame_space (space->start, slot_offset);
448 if (slot_offset + size < space->start + space->length)
449 add_frame_space (slot_offset + size,
450 space->start + space->length);
451 goto found_space;
452 }
453 }
454 }
455 else if (!STACK_ALIGNMENT_NEEDED)
456 {
457 slot_offset = frame_offset;
458 goto found_space;
459 }
460
461 old_frame_offset = frame_offset;
462
463 if (FRAME_GROWS_DOWNWARD)
464 {
465 frame_offset -= size;
466 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
467
468 if (kind & ASLK_RECORD_PAD)
469 {
470 if (slot_offset > frame_offset)
471 add_frame_space (frame_offset, slot_offset);
472 if (slot_offset + size < old_frame_offset)
473 add_frame_space (slot_offset + size, old_frame_offset);
474 }
475 }
476 else
477 {
478 frame_offset += size;
479 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
480
481 if (kind & ASLK_RECORD_PAD)
482 {
483 if (slot_offset > old_frame_offset)
484 add_frame_space (old_frame_offset, slot_offset);
485 if (slot_offset + size < frame_offset)
486 add_frame_space (slot_offset + size, frame_offset);
487 }
488 }
489
490 found_space:
491 /* On a big-endian machine, if we are allocating more space than we will use,
492 use the least significant bytes of those that are allocated. */
493 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
494 bigend_correction = size - GET_MODE_SIZE (mode);
495
496 /* If we have already instantiated virtual registers, return the actual
497 address relative to the frame pointer. */
498 if (virtuals_instantiated)
499 addr = plus_constant (Pmode, frame_pointer_rtx,
500 trunc_int_for_mode
501 (slot_offset + bigend_correction
502 + targetm.starting_frame_offset (), Pmode));
503 else
504 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
505 trunc_int_for_mode
506 (slot_offset + bigend_correction,
507 Pmode));
508
509 x = gen_rtx_MEM (mode, addr);
510 set_mem_align (x, alignment_in_bits);
511 MEM_NOTRAP_P (x) = 1;
512
513 vec_safe_push (stack_slot_list, x);
514
515 if (frame_offset_overflow (frame_offset, current_function_decl))
516 frame_offset = 0;
517
518 return x;
519 }
520
521 /* Wrap up assign_stack_local_1 with last parameter as false. */
522
523 rtx
524 assign_stack_local (machine_mode mode, HOST_WIDE_INT size, int align)
525 {
526 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
527 }
528 \f
529 /* In order to evaluate some expressions, such as function calls returning
530 structures in memory, we need to temporarily allocate stack locations.
531 We record each allocated temporary in the following structure.
532
533 Associated with each temporary slot is a nesting level. When we pop up
534 one level, all temporaries associated with the previous level are freed.
535 Normally, all temporaries are freed after the execution of the statement
536 in which they were created. However, if we are inside a ({...}) grouping,
537 the result may be in a temporary and hence must be preserved. If the
538 result could be in a temporary, we preserve it if we can determine which
539 one it is in. If we cannot determine which temporary may contain the
540 result, all temporaries are preserved. A temporary is preserved by
541 pretending it was allocated at the previous nesting level. */
542
543 struct GTY(()) temp_slot {
544 /* Points to next temporary slot. */
545 struct temp_slot *next;
546 /* Points to previous temporary slot. */
547 struct temp_slot *prev;
548 /* The rtx to used to reference the slot. */
549 rtx slot;
550 /* The size, in units, of the slot. */
551 HOST_WIDE_INT size;
552 /* The type of the object in the slot, or zero if it doesn't correspond
553 to a type. We use this to determine whether a slot can be reused.
554 It can be reused if objects of the type of the new slot will always
555 conflict with objects of the type of the old slot. */
556 tree type;
557 /* The alignment (in bits) of the slot. */
558 unsigned int align;
559 /* Nonzero if this temporary is currently in use. */
560 char in_use;
561 /* Nesting level at which this slot is being used. */
562 int level;
563 /* The offset of the slot from the frame_pointer, including extra space
564 for alignment. This info is for combine_temp_slots. */
565 HOST_WIDE_INT base_offset;
566 /* The size of the slot, including extra space for alignment. This
567 info is for combine_temp_slots. */
568 HOST_WIDE_INT full_size;
569 };
570
571 /* Entry for the below hash table. */
572 struct GTY((for_user)) temp_slot_address_entry {
573 hashval_t hash;
574 rtx address;
575 struct temp_slot *temp_slot;
576 };
577
578 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
579 {
580 static hashval_t hash (temp_slot_address_entry *);
581 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
582 };
583
584 /* A table of addresses that represent a stack slot. The table is a mapping
585 from address RTXen to a temp slot. */
586 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
587 static size_t n_temp_slots_in_use;
588
589 /* Removes temporary slot TEMP from LIST. */
590
591 static void
592 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
593 {
594 if (temp->next)
595 temp->next->prev = temp->prev;
596 if (temp->prev)
597 temp->prev->next = temp->next;
598 else
599 *list = temp->next;
600
601 temp->prev = temp->next = NULL;
602 }
603
604 /* Inserts temporary slot TEMP to LIST. */
605
606 static void
607 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
608 {
609 temp->next = *list;
610 if (*list)
611 (*list)->prev = temp;
612 temp->prev = NULL;
613 *list = temp;
614 }
615
616 /* Returns the list of used temp slots at LEVEL. */
617
618 static struct temp_slot **
619 temp_slots_at_level (int level)
620 {
621 if (level >= (int) vec_safe_length (used_temp_slots))
622 vec_safe_grow_cleared (used_temp_slots, level + 1);
623
624 return &(*used_temp_slots)[level];
625 }
626
627 /* Returns the maximal temporary slot level. */
628
629 static int
630 max_slot_level (void)
631 {
632 if (!used_temp_slots)
633 return -1;
634
635 return used_temp_slots->length () - 1;
636 }
637
638 /* Moves temporary slot TEMP to LEVEL. */
639
640 static void
641 move_slot_to_level (struct temp_slot *temp, int level)
642 {
643 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
644 insert_slot_to_list (temp, temp_slots_at_level (level));
645 temp->level = level;
646 }
647
648 /* Make temporary slot TEMP available. */
649
650 static void
651 make_slot_available (struct temp_slot *temp)
652 {
653 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
654 insert_slot_to_list (temp, &avail_temp_slots);
655 temp->in_use = 0;
656 temp->level = -1;
657 n_temp_slots_in_use--;
658 }
659
660 /* Compute the hash value for an address -> temp slot mapping.
661 The value is cached on the mapping entry. */
662 static hashval_t
663 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
664 {
665 int do_not_record = 0;
666 return hash_rtx (t->address, GET_MODE (t->address),
667 &do_not_record, NULL, false);
668 }
669
670 /* Return the hash value for an address -> temp slot mapping. */
671 hashval_t
672 temp_address_hasher::hash (temp_slot_address_entry *t)
673 {
674 return t->hash;
675 }
676
677 /* Compare two address -> temp slot mapping entries. */
678 bool
679 temp_address_hasher::equal (temp_slot_address_entry *t1,
680 temp_slot_address_entry *t2)
681 {
682 return exp_equiv_p (t1->address, t2->address, 0, true);
683 }
684
685 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
686 static void
687 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
688 {
689 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
690 t->address = address;
691 t->temp_slot = temp_slot;
692 t->hash = temp_slot_address_compute_hash (t);
693 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
694 }
695
696 /* Remove an address -> temp slot mapping entry if the temp slot is
697 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
698 int
699 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
700 {
701 const struct temp_slot_address_entry *t = *slot;
702 if (! t->temp_slot->in_use)
703 temp_slot_address_table->clear_slot (slot);
704 return 1;
705 }
706
707 /* Remove all mappings of addresses to unused temp slots. */
708 static void
709 remove_unused_temp_slot_addresses (void)
710 {
711 /* Use quicker clearing if there aren't any active temp slots. */
712 if (n_temp_slots_in_use)
713 temp_slot_address_table->traverse
714 <void *, remove_unused_temp_slot_addresses_1> (NULL);
715 else
716 temp_slot_address_table->empty ();
717 }
718
719 /* Find the temp slot corresponding to the object at address X. */
720
721 static struct temp_slot *
722 find_temp_slot_from_address (rtx x)
723 {
724 struct temp_slot *p;
725 struct temp_slot_address_entry tmp, *t;
726
727 /* First try the easy way:
728 See if X exists in the address -> temp slot mapping. */
729 tmp.address = x;
730 tmp.temp_slot = NULL;
731 tmp.hash = temp_slot_address_compute_hash (&tmp);
732 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
733 if (t)
734 return t->temp_slot;
735
736 /* If we have a sum involving a register, see if it points to a temp
737 slot. */
738 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
739 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
740 return p;
741 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
742 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
743 return p;
744
745 /* Last resort: Address is a virtual stack var address. */
746 if (GET_CODE (x) == PLUS
747 && XEXP (x, 0) == virtual_stack_vars_rtx
748 && CONST_INT_P (XEXP (x, 1)))
749 {
750 int i;
751 for (i = max_slot_level (); i >= 0; i--)
752 for (p = *temp_slots_at_level (i); p; p = p->next)
753 {
754 if (INTVAL (XEXP (x, 1)) >= p->base_offset
755 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
756 return p;
757 }
758 }
759
760 return NULL;
761 }
762 \f
763 /* Allocate a temporary stack slot and record it for possible later
764 reuse.
765
766 MODE is the machine mode to be given to the returned rtx.
767
768 SIZE is the size in units of the space required. We do no rounding here
769 since assign_stack_local will do any required rounding.
770
771 TYPE is the type that will be used for the stack slot. */
772
773 rtx
774 assign_stack_temp_for_type (machine_mode mode, HOST_WIDE_INT size,
775 tree type)
776 {
777 unsigned int align;
778 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
779 rtx slot;
780
781 /* If SIZE is -1 it means that somebody tried to allocate a temporary
782 of a variable size. */
783 gcc_assert (size != -1);
784
785 align = get_stack_local_alignment (type, mode);
786
787 /* Try to find an available, already-allocated temporary of the proper
788 mode which meets the size and alignment requirements. Choose the
789 smallest one with the closest alignment.
790
791 If assign_stack_temp is called outside of the tree->rtl expansion,
792 we cannot reuse the stack slots (that may still refer to
793 VIRTUAL_STACK_VARS_REGNUM). */
794 if (!virtuals_instantiated)
795 {
796 for (p = avail_temp_slots; p; p = p->next)
797 {
798 if (p->align >= align && p->size >= size
799 && GET_MODE (p->slot) == mode
800 && objects_must_conflict_p (p->type, type)
801 && (best_p == 0 || best_p->size > p->size
802 || (best_p->size == p->size && best_p->align > p->align)))
803 {
804 if (p->align == align && p->size == size)
805 {
806 selected = p;
807 cut_slot_from_list (selected, &avail_temp_slots);
808 best_p = 0;
809 break;
810 }
811 best_p = p;
812 }
813 }
814 }
815
816 /* Make our best, if any, the one to use. */
817 if (best_p)
818 {
819 selected = best_p;
820 cut_slot_from_list (selected, &avail_temp_slots);
821
822 /* If there are enough aligned bytes left over, make them into a new
823 temp_slot so that the extra bytes don't get wasted. Do this only
824 for BLKmode slots, so that we can be sure of the alignment. */
825 if (GET_MODE (best_p->slot) == BLKmode)
826 {
827 int alignment = best_p->align / BITS_PER_UNIT;
828 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
829
830 if (best_p->size - rounded_size >= alignment)
831 {
832 p = ggc_alloc<temp_slot> ();
833 p->in_use = 0;
834 p->size = best_p->size - rounded_size;
835 p->base_offset = best_p->base_offset + rounded_size;
836 p->full_size = best_p->full_size - rounded_size;
837 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
838 p->align = best_p->align;
839 p->type = best_p->type;
840 insert_slot_to_list (p, &avail_temp_slots);
841
842 vec_safe_push (stack_slot_list, p->slot);
843
844 best_p->size = rounded_size;
845 best_p->full_size = rounded_size;
846 }
847 }
848 }
849
850 /* If we still didn't find one, make a new temporary. */
851 if (selected == 0)
852 {
853 HOST_WIDE_INT frame_offset_old = frame_offset;
854
855 p = ggc_alloc<temp_slot> ();
856
857 /* We are passing an explicit alignment request to assign_stack_local.
858 One side effect of that is assign_stack_local will not round SIZE
859 to ensure the frame offset remains suitably aligned.
860
861 So for requests which depended on the rounding of SIZE, we go ahead
862 and round it now. We also make sure ALIGNMENT is at least
863 BIGGEST_ALIGNMENT. */
864 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
865 p->slot = assign_stack_local_1 (mode,
866 (mode == BLKmode
867 ? CEIL_ROUND (size,
868 (int) align
869 / BITS_PER_UNIT)
870 : size),
871 align, 0);
872
873 p->align = align;
874
875 /* The following slot size computation is necessary because we don't
876 know the actual size of the temporary slot until assign_stack_local
877 has performed all the frame alignment and size rounding for the
878 requested temporary. Note that extra space added for alignment
879 can be either above or below this stack slot depending on which
880 way the frame grows. We include the extra space if and only if it
881 is above this slot. */
882 if (FRAME_GROWS_DOWNWARD)
883 p->size = frame_offset_old - frame_offset;
884 else
885 p->size = size;
886
887 /* Now define the fields used by combine_temp_slots. */
888 if (FRAME_GROWS_DOWNWARD)
889 {
890 p->base_offset = frame_offset;
891 p->full_size = frame_offset_old - frame_offset;
892 }
893 else
894 {
895 p->base_offset = frame_offset_old;
896 p->full_size = frame_offset - frame_offset_old;
897 }
898
899 selected = p;
900 }
901
902 p = selected;
903 p->in_use = 1;
904 p->type = type;
905 p->level = temp_slot_level;
906 n_temp_slots_in_use++;
907
908 pp = temp_slots_at_level (p->level);
909 insert_slot_to_list (p, pp);
910 insert_temp_slot_address (XEXP (p->slot, 0), p);
911
912 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
913 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
914 vec_safe_push (stack_slot_list, slot);
915
916 /* If we know the alias set for the memory that will be used, use
917 it. If there's no TYPE, then we don't know anything about the
918 alias set for the memory. */
919 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
920 set_mem_align (slot, align);
921
922 /* If a type is specified, set the relevant flags. */
923 if (type != 0)
924 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
925 MEM_NOTRAP_P (slot) = 1;
926
927 return slot;
928 }
929
930 /* Allocate a temporary stack slot and record it for possible later
931 reuse. First two arguments are same as in preceding function. */
932
933 rtx
934 assign_stack_temp (machine_mode mode, HOST_WIDE_INT size)
935 {
936 return assign_stack_temp_for_type (mode, size, NULL_TREE);
937 }
938 \f
939 /* Assign a temporary.
940 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
941 and so that should be used in error messages. In either case, we
942 allocate of the given type.
943 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
944 it is 0 if a register is OK.
945 DONT_PROMOTE is 1 if we should not promote values in register
946 to wider modes. */
947
948 rtx
949 assign_temp (tree type_or_decl, int memory_required,
950 int dont_promote ATTRIBUTE_UNUSED)
951 {
952 tree type, decl;
953 machine_mode mode;
954 #ifdef PROMOTE_MODE
955 int unsignedp;
956 #endif
957
958 if (DECL_P (type_or_decl))
959 decl = type_or_decl, type = TREE_TYPE (decl);
960 else
961 decl = NULL, type = type_or_decl;
962
963 mode = TYPE_MODE (type);
964 #ifdef PROMOTE_MODE
965 unsignedp = TYPE_UNSIGNED (type);
966 #endif
967
968 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
969 end. See also create_tmp_var for the gimplification-time check. */
970 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
971
972 if (mode == BLKmode || memory_required)
973 {
974 HOST_WIDE_INT size = int_size_in_bytes (type);
975 rtx tmp;
976
977 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
978 problems with allocating the stack space. */
979 if (size == 0)
980 size = 1;
981
982 /* Unfortunately, we don't yet know how to allocate variable-sized
983 temporaries. However, sometimes we can find a fixed upper limit on
984 the size, so try that instead. */
985 else if (size == -1)
986 size = max_int_size_in_bytes (type);
987
988 /* The size of the temporary may be too large to fit into an integer. */
989 /* ??? Not sure this should happen except for user silliness, so limit
990 this to things that aren't compiler-generated temporaries. The
991 rest of the time we'll die in assign_stack_temp_for_type. */
992 if (decl && size == -1
993 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
994 {
995 error ("size of variable %q+D is too large", decl);
996 size = 1;
997 }
998
999 tmp = assign_stack_temp_for_type (mode, size, type);
1000 return tmp;
1001 }
1002
1003 #ifdef PROMOTE_MODE
1004 if (! dont_promote)
1005 mode = promote_mode (type, mode, &unsignedp);
1006 #endif
1007
1008 return gen_reg_rtx (mode);
1009 }
1010 \f
1011 /* Combine temporary stack slots which are adjacent on the stack.
1012
1013 This allows for better use of already allocated stack space. This is only
1014 done for BLKmode slots because we can be sure that we won't have alignment
1015 problems in this case. */
1016
1017 static void
1018 combine_temp_slots (void)
1019 {
1020 struct temp_slot *p, *q, *next, *next_q;
1021 int num_slots;
1022
1023 /* We can't combine slots, because the information about which slot
1024 is in which alias set will be lost. */
1025 if (flag_strict_aliasing)
1026 return;
1027
1028 /* If there are a lot of temp slots, don't do anything unless
1029 high levels of optimization. */
1030 if (! flag_expensive_optimizations)
1031 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1032 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1033 return;
1034
1035 for (p = avail_temp_slots; p; p = next)
1036 {
1037 int delete_p = 0;
1038
1039 next = p->next;
1040
1041 if (GET_MODE (p->slot) != BLKmode)
1042 continue;
1043
1044 for (q = p->next; q; q = next_q)
1045 {
1046 int delete_q = 0;
1047
1048 next_q = q->next;
1049
1050 if (GET_MODE (q->slot) != BLKmode)
1051 continue;
1052
1053 if (p->base_offset + p->full_size == q->base_offset)
1054 {
1055 /* Q comes after P; combine Q into P. */
1056 p->size += q->size;
1057 p->full_size += q->full_size;
1058 delete_q = 1;
1059 }
1060 else if (q->base_offset + q->full_size == p->base_offset)
1061 {
1062 /* P comes after Q; combine P into Q. */
1063 q->size += p->size;
1064 q->full_size += p->full_size;
1065 delete_p = 1;
1066 break;
1067 }
1068 if (delete_q)
1069 cut_slot_from_list (q, &avail_temp_slots);
1070 }
1071
1072 /* Either delete P or advance past it. */
1073 if (delete_p)
1074 cut_slot_from_list (p, &avail_temp_slots);
1075 }
1076 }
1077 \f
1078 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1079 slot that previously was known by OLD_RTX. */
1080
1081 void
1082 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1083 {
1084 struct temp_slot *p;
1085
1086 if (rtx_equal_p (old_rtx, new_rtx))
1087 return;
1088
1089 p = find_temp_slot_from_address (old_rtx);
1090
1091 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1092 NEW_RTX is a register, see if one operand of the PLUS is a
1093 temporary location. If so, NEW_RTX points into it. Otherwise,
1094 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1095 in common between them. If so, try a recursive call on those
1096 values. */
1097 if (p == 0)
1098 {
1099 if (GET_CODE (old_rtx) != PLUS)
1100 return;
1101
1102 if (REG_P (new_rtx))
1103 {
1104 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1105 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1106 return;
1107 }
1108 else if (GET_CODE (new_rtx) != PLUS)
1109 return;
1110
1111 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1112 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1113 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1114 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1115 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1116 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1117 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1118 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1119
1120 return;
1121 }
1122
1123 /* Otherwise add an alias for the temp's address. */
1124 insert_temp_slot_address (new_rtx, p);
1125 }
1126
1127 /* If X could be a reference to a temporary slot, mark that slot as
1128 belonging to the to one level higher than the current level. If X
1129 matched one of our slots, just mark that one. Otherwise, we can't
1130 easily predict which it is, so upgrade all of them.
1131
1132 This is called when an ({...}) construct occurs and a statement
1133 returns a value in memory. */
1134
1135 void
1136 preserve_temp_slots (rtx x)
1137 {
1138 struct temp_slot *p = 0, *next;
1139
1140 if (x == 0)
1141 return;
1142
1143 /* If X is a register that is being used as a pointer, see if we have
1144 a temporary slot we know it points to. */
1145 if (REG_P (x) && REG_POINTER (x))
1146 p = find_temp_slot_from_address (x);
1147
1148 /* If X is not in memory or is at a constant address, it cannot be in
1149 a temporary slot. */
1150 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1151 return;
1152
1153 /* First see if we can find a match. */
1154 if (p == 0)
1155 p = find_temp_slot_from_address (XEXP (x, 0));
1156
1157 if (p != 0)
1158 {
1159 if (p->level == temp_slot_level)
1160 move_slot_to_level (p, temp_slot_level - 1);
1161 return;
1162 }
1163
1164 /* Otherwise, preserve all non-kept slots at this level. */
1165 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1166 {
1167 next = p->next;
1168 move_slot_to_level (p, temp_slot_level - 1);
1169 }
1170 }
1171
1172 /* Free all temporaries used so far. This is normally called at the
1173 end of generating code for a statement. */
1174
1175 void
1176 free_temp_slots (void)
1177 {
1178 struct temp_slot *p, *next;
1179 bool some_available = false;
1180
1181 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1182 {
1183 next = p->next;
1184 make_slot_available (p);
1185 some_available = true;
1186 }
1187
1188 if (some_available)
1189 {
1190 remove_unused_temp_slot_addresses ();
1191 combine_temp_slots ();
1192 }
1193 }
1194
1195 /* Push deeper into the nesting level for stack temporaries. */
1196
1197 void
1198 push_temp_slots (void)
1199 {
1200 temp_slot_level++;
1201 }
1202
1203 /* Pop a temporary nesting level. All slots in use in the current level
1204 are freed. */
1205
1206 void
1207 pop_temp_slots (void)
1208 {
1209 free_temp_slots ();
1210 temp_slot_level--;
1211 }
1212
1213 /* Initialize temporary slots. */
1214
1215 void
1216 init_temp_slots (void)
1217 {
1218 /* We have not allocated any temporaries yet. */
1219 avail_temp_slots = 0;
1220 vec_alloc (used_temp_slots, 0);
1221 temp_slot_level = 0;
1222 n_temp_slots_in_use = 0;
1223
1224 /* Set up the table to map addresses to temp slots. */
1225 if (! temp_slot_address_table)
1226 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1227 else
1228 temp_slot_address_table->empty ();
1229 }
1230 \f
1231 /* Functions and data structures to keep track of the values hard regs
1232 had at the start of the function. */
1233
1234 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1235 and has_hard_reg_initial_val.. */
1236 struct GTY(()) initial_value_pair {
1237 rtx hard_reg;
1238 rtx pseudo;
1239 };
1240 /* ??? This could be a VEC but there is currently no way to define an
1241 opaque VEC type. This could be worked around by defining struct
1242 initial_value_pair in function.h. */
1243 struct GTY(()) initial_value_struct {
1244 int num_entries;
1245 int max_entries;
1246 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1247 };
1248
1249 /* If a pseudo represents an initial hard reg (or expression), return
1250 it, else return NULL_RTX. */
1251
1252 rtx
1253 get_hard_reg_initial_reg (rtx reg)
1254 {
1255 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1256 int i;
1257
1258 if (ivs == 0)
1259 return NULL_RTX;
1260
1261 for (i = 0; i < ivs->num_entries; i++)
1262 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1263 return ivs->entries[i].hard_reg;
1264
1265 return NULL_RTX;
1266 }
1267
1268 /* Make sure that there's a pseudo register of mode MODE that stores the
1269 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1270
1271 rtx
1272 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1273 {
1274 struct initial_value_struct *ivs;
1275 rtx rv;
1276
1277 rv = has_hard_reg_initial_val (mode, regno);
1278 if (rv)
1279 return rv;
1280
1281 ivs = crtl->hard_reg_initial_vals;
1282 if (ivs == 0)
1283 {
1284 ivs = ggc_alloc<initial_value_struct> ();
1285 ivs->num_entries = 0;
1286 ivs->max_entries = 5;
1287 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1288 crtl->hard_reg_initial_vals = ivs;
1289 }
1290
1291 if (ivs->num_entries >= ivs->max_entries)
1292 {
1293 ivs->max_entries += 5;
1294 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1295 ivs->max_entries);
1296 }
1297
1298 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1299 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1300
1301 return ivs->entries[ivs->num_entries++].pseudo;
1302 }
1303
1304 /* See if get_hard_reg_initial_val has been used to create a pseudo
1305 for the initial value of hard register REGNO in mode MODE. Return
1306 the associated pseudo if so, otherwise return NULL. */
1307
1308 rtx
1309 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1310 {
1311 struct initial_value_struct *ivs;
1312 int i;
1313
1314 ivs = crtl->hard_reg_initial_vals;
1315 if (ivs != 0)
1316 for (i = 0; i < ivs->num_entries; i++)
1317 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1318 && REGNO (ivs->entries[i].hard_reg) == regno)
1319 return ivs->entries[i].pseudo;
1320
1321 return NULL_RTX;
1322 }
1323
1324 unsigned int
1325 emit_initial_value_sets (void)
1326 {
1327 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1328 int i;
1329 rtx_insn *seq;
1330
1331 if (ivs == 0)
1332 return 0;
1333
1334 start_sequence ();
1335 for (i = 0; i < ivs->num_entries; i++)
1336 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1337 seq = get_insns ();
1338 end_sequence ();
1339
1340 emit_insn_at_entry (seq);
1341 return 0;
1342 }
1343
1344 /* Return the hardreg-pseudoreg initial values pair entry I and
1345 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1346 bool
1347 initial_value_entry (int i, rtx *hreg, rtx *preg)
1348 {
1349 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1350 if (!ivs || i >= ivs->num_entries)
1351 return false;
1352
1353 *hreg = ivs->entries[i].hard_reg;
1354 *preg = ivs->entries[i].pseudo;
1355 return true;
1356 }
1357 \f
1358 /* These routines are responsible for converting virtual register references
1359 to the actual hard register references once RTL generation is complete.
1360
1361 The following four variables are used for communication between the
1362 routines. They contain the offsets of the virtual registers from their
1363 respective hard registers. */
1364
1365 static int in_arg_offset;
1366 static int var_offset;
1367 static int dynamic_offset;
1368 static int out_arg_offset;
1369 static int cfa_offset;
1370
1371 /* In most machines, the stack pointer register is equivalent to the bottom
1372 of the stack. */
1373
1374 #ifndef STACK_POINTER_OFFSET
1375 #define STACK_POINTER_OFFSET 0
1376 #endif
1377
1378 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1379 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1380 #endif
1381
1382 /* If not defined, pick an appropriate default for the offset of dynamically
1383 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1384 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1385
1386 #ifndef STACK_DYNAMIC_OFFSET
1387
1388 /* The bottom of the stack points to the actual arguments. If
1389 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1390 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1391 stack space for register parameters is not pushed by the caller, but
1392 rather part of the fixed stack areas and hence not included in
1393 `crtl->outgoing_args_size'. Nevertheless, we must allow
1394 for it when allocating stack dynamic objects. */
1395
1396 #ifdef INCOMING_REG_PARM_STACK_SPACE
1397 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1398 ((ACCUMULATE_OUTGOING_ARGS \
1399 ? (crtl->outgoing_args_size \
1400 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1401 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1402 : 0) + (STACK_POINTER_OFFSET))
1403 #else
1404 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1405 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1406 + (STACK_POINTER_OFFSET))
1407 #endif
1408 #endif
1409
1410 \f
1411 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1412 is a virtual register, return the equivalent hard register and set the
1413 offset indirectly through the pointer. Otherwise, return 0. */
1414
1415 static rtx
1416 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1417 {
1418 rtx new_rtx;
1419 HOST_WIDE_INT offset;
1420
1421 if (x == virtual_incoming_args_rtx)
1422 {
1423 if (stack_realign_drap)
1424 {
1425 /* Replace virtual_incoming_args_rtx with internal arg
1426 pointer if DRAP is used to realign stack. */
1427 new_rtx = crtl->args.internal_arg_pointer;
1428 offset = 0;
1429 }
1430 else
1431 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1432 }
1433 else if (x == virtual_stack_vars_rtx)
1434 new_rtx = frame_pointer_rtx, offset = var_offset;
1435 else if (x == virtual_stack_dynamic_rtx)
1436 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1437 else if (x == virtual_outgoing_args_rtx)
1438 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1439 else if (x == virtual_cfa_rtx)
1440 {
1441 #ifdef FRAME_POINTER_CFA_OFFSET
1442 new_rtx = frame_pointer_rtx;
1443 #else
1444 new_rtx = arg_pointer_rtx;
1445 #endif
1446 offset = cfa_offset;
1447 }
1448 else if (x == virtual_preferred_stack_boundary_rtx)
1449 {
1450 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1451 offset = 0;
1452 }
1453 else
1454 return NULL_RTX;
1455
1456 *poffset = offset;
1457 return new_rtx;
1458 }
1459
1460 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1461 registers present inside of *LOC. The expression is simplified,
1462 as much as possible, but is not to be considered "valid" in any sense
1463 implied by the target. Return true if any change is made. */
1464
1465 static bool
1466 instantiate_virtual_regs_in_rtx (rtx *loc)
1467 {
1468 if (!*loc)
1469 return false;
1470 bool changed = false;
1471 subrtx_ptr_iterator::array_type array;
1472 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1473 {
1474 rtx *loc = *iter;
1475 if (rtx x = *loc)
1476 {
1477 rtx new_rtx;
1478 HOST_WIDE_INT offset;
1479 switch (GET_CODE (x))
1480 {
1481 case REG:
1482 new_rtx = instantiate_new_reg (x, &offset);
1483 if (new_rtx)
1484 {
1485 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1486 changed = true;
1487 }
1488 iter.skip_subrtxes ();
1489 break;
1490
1491 case PLUS:
1492 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1493 if (new_rtx)
1494 {
1495 XEXP (x, 0) = new_rtx;
1496 *loc = plus_constant (GET_MODE (x), x, offset, true);
1497 changed = true;
1498 iter.skip_subrtxes ();
1499 break;
1500 }
1501
1502 /* FIXME -- from old code */
1503 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1504 we can commute the PLUS and SUBREG because pointers into the
1505 frame are well-behaved. */
1506 break;
1507
1508 default:
1509 break;
1510 }
1511 }
1512 }
1513 return changed;
1514 }
1515
1516 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1517 matches the predicate for insn CODE operand OPERAND. */
1518
1519 static int
1520 safe_insn_predicate (int code, int operand, rtx x)
1521 {
1522 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1523 }
1524
1525 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1526 registers present inside of insn. The result will be a valid insn. */
1527
1528 static void
1529 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1530 {
1531 HOST_WIDE_INT offset;
1532 int insn_code, i;
1533 bool any_change = false;
1534 rtx set, new_rtx, x;
1535 rtx_insn *seq;
1536
1537 /* There are some special cases to be handled first. */
1538 set = single_set (insn);
1539 if (set)
1540 {
1541 /* We're allowed to assign to a virtual register. This is interpreted
1542 to mean that the underlying register gets assigned the inverse
1543 transformation. This is used, for example, in the handling of
1544 non-local gotos. */
1545 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1546 if (new_rtx)
1547 {
1548 start_sequence ();
1549
1550 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1551 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1552 gen_int_mode (-offset, GET_MODE (new_rtx)));
1553 x = force_operand (x, new_rtx);
1554 if (x != new_rtx)
1555 emit_move_insn (new_rtx, x);
1556
1557 seq = get_insns ();
1558 end_sequence ();
1559
1560 emit_insn_before (seq, insn);
1561 delete_insn (insn);
1562 return;
1563 }
1564
1565 /* Handle a straight copy from a virtual register by generating a
1566 new add insn. The difference between this and falling through
1567 to the generic case is avoiding a new pseudo and eliminating a
1568 move insn in the initial rtl stream. */
1569 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1570 if (new_rtx && offset != 0
1571 && REG_P (SET_DEST (set))
1572 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1573 {
1574 start_sequence ();
1575
1576 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1577 gen_int_mode (offset,
1578 GET_MODE (SET_DEST (set))),
1579 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1580 if (x != SET_DEST (set))
1581 emit_move_insn (SET_DEST (set), x);
1582
1583 seq = get_insns ();
1584 end_sequence ();
1585
1586 emit_insn_before (seq, insn);
1587 delete_insn (insn);
1588 return;
1589 }
1590
1591 extract_insn (insn);
1592 insn_code = INSN_CODE (insn);
1593
1594 /* Handle a plus involving a virtual register by determining if the
1595 operands remain valid if they're modified in place. */
1596 if (GET_CODE (SET_SRC (set)) == PLUS
1597 && recog_data.n_operands >= 3
1598 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1599 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1600 && CONST_INT_P (recog_data.operand[2])
1601 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1602 {
1603 offset += INTVAL (recog_data.operand[2]);
1604
1605 /* If the sum is zero, then replace with a plain move. */
1606 if (offset == 0
1607 && REG_P (SET_DEST (set))
1608 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1609 {
1610 start_sequence ();
1611 emit_move_insn (SET_DEST (set), new_rtx);
1612 seq = get_insns ();
1613 end_sequence ();
1614
1615 emit_insn_before (seq, insn);
1616 delete_insn (insn);
1617 return;
1618 }
1619
1620 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1621
1622 /* Using validate_change and apply_change_group here leaves
1623 recog_data in an invalid state. Since we know exactly what
1624 we want to check, do those two by hand. */
1625 if (safe_insn_predicate (insn_code, 1, new_rtx)
1626 && safe_insn_predicate (insn_code, 2, x))
1627 {
1628 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1629 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1630 any_change = true;
1631
1632 /* Fall through into the regular operand fixup loop in
1633 order to take care of operands other than 1 and 2. */
1634 }
1635 }
1636 }
1637 else
1638 {
1639 extract_insn (insn);
1640 insn_code = INSN_CODE (insn);
1641 }
1642
1643 /* In the general case, we expect virtual registers to appear only in
1644 operands, and then only as either bare registers or inside memories. */
1645 for (i = 0; i < recog_data.n_operands; ++i)
1646 {
1647 x = recog_data.operand[i];
1648 switch (GET_CODE (x))
1649 {
1650 case MEM:
1651 {
1652 rtx addr = XEXP (x, 0);
1653
1654 if (!instantiate_virtual_regs_in_rtx (&addr))
1655 continue;
1656
1657 start_sequence ();
1658 x = replace_equiv_address (x, addr, true);
1659 /* It may happen that the address with the virtual reg
1660 was valid (e.g. based on the virtual stack reg, which might
1661 be acceptable to the predicates with all offsets), whereas
1662 the address now isn't anymore, for instance when the address
1663 is still offsetted, but the base reg isn't virtual-stack-reg
1664 anymore. Below we would do a force_reg on the whole operand,
1665 but this insn might actually only accept memory. Hence,
1666 before doing that last resort, try to reload the address into
1667 a register, so this operand stays a MEM. */
1668 if (!safe_insn_predicate (insn_code, i, x))
1669 {
1670 addr = force_reg (GET_MODE (addr), addr);
1671 x = replace_equiv_address (x, addr, true);
1672 }
1673 seq = get_insns ();
1674 end_sequence ();
1675 if (seq)
1676 emit_insn_before (seq, insn);
1677 }
1678 break;
1679
1680 case REG:
1681 new_rtx = instantiate_new_reg (x, &offset);
1682 if (new_rtx == NULL)
1683 continue;
1684 if (offset == 0)
1685 x = new_rtx;
1686 else
1687 {
1688 start_sequence ();
1689
1690 /* Careful, special mode predicates may have stuff in
1691 insn_data[insn_code].operand[i].mode that isn't useful
1692 to us for computing a new value. */
1693 /* ??? Recognize address_operand and/or "p" constraints
1694 to see if (plus new offset) is a valid before we put
1695 this through expand_simple_binop. */
1696 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1697 gen_int_mode (offset, GET_MODE (x)),
1698 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1699 seq = get_insns ();
1700 end_sequence ();
1701 emit_insn_before (seq, insn);
1702 }
1703 break;
1704
1705 case SUBREG:
1706 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1707 if (new_rtx == NULL)
1708 continue;
1709 if (offset != 0)
1710 {
1711 start_sequence ();
1712 new_rtx = expand_simple_binop
1713 (GET_MODE (new_rtx), PLUS, new_rtx,
1714 gen_int_mode (offset, GET_MODE (new_rtx)),
1715 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1716 seq = get_insns ();
1717 end_sequence ();
1718 emit_insn_before (seq, insn);
1719 }
1720 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1721 GET_MODE (new_rtx), SUBREG_BYTE (x));
1722 gcc_assert (x);
1723 break;
1724
1725 default:
1726 continue;
1727 }
1728
1729 /* At this point, X contains the new value for the operand.
1730 Validate the new value vs the insn predicate. Note that
1731 asm insns will have insn_code -1 here. */
1732 if (!safe_insn_predicate (insn_code, i, x))
1733 {
1734 start_sequence ();
1735 if (REG_P (x))
1736 {
1737 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1738 x = copy_to_reg (x);
1739 }
1740 else
1741 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1742 seq = get_insns ();
1743 end_sequence ();
1744 if (seq)
1745 emit_insn_before (seq, insn);
1746 }
1747
1748 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1749 any_change = true;
1750 }
1751
1752 if (any_change)
1753 {
1754 /* Propagate operand changes into the duplicates. */
1755 for (i = 0; i < recog_data.n_dups; ++i)
1756 *recog_data.dup_loc[i]
1757 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1758
1759 /* Force re-recognition of the instruction for validation. */
1760 INSN_CODE (insn) = -1;
1761 }
1762
1763 if (asm_noperands (PATTERN (insn)) >= 0)
1764 {
1765 if (!check_asm_operands (PATTERN (insn)))
1766 {
1767 error_for_asm (insn, "impossible constraint in %<asm%>");
1768 /* For asm goto, instead of fixing up all the edges
1769 just clear the template and clear input operands
1770 (asm goto doesn't have any output operands). */
1771 if (JUMP_P (insn))
1772 {
1773 rtx asm_op = extract_asm_operands (PATTERN (insn));
1774 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1775 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1776 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1777 }
1778 else
1779 delete_insn (insn);
1780 }
1781 }
1782 else
1783 {
1784 if (recog_memoized (insn) < 0)
1785 fatal_insn_not_found (insn);
1786 }
1787 }
1788
1789 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1790 do any instantiation required. */
1791
1792 void
1793 instantiate_decl_rtl (rtx x)
1794 {
1795 rtx addr;
1796
1797 if (x == 0)
1798 return;
1799
1800 /* If this is a CONCAT, recurse for the pieces. */
1801 if (GET_CODE (x) == CONCAT)
1802 {
1803 instantiate_decl_rtl (XEXP (x, 0));
1804 instantiate_decl_rtl (XEXP (x, 1));
1805 return;
1806 }
1807
1808 /* If this is not a MEM, no need to do anything. Similarly if the
1809 address is a constant or a register that is not a virtual register. */
1810 if (!MEM_P (x))
1811 return;
1812
1813 addr = XEXP (x, 0);
1814 if (CONSTANT_P (addr)
1815 || (REG_P (addr)
1816 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1817 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1818 return;
1819
1820 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1821 }
1822
1823 /* Helper for instantiate_decls called via walk_tree: Process all decls
1824 in the given DECL_VALUE_EXPR. */
1825
1826 static tree
1827 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1828 {
1829 tree t = *tp;
1830 if (! EXPR_P (t))
1831 {
1832 *walk_subtrees = 0;
1833 if (DECL_P (t))
1834 {
1835 if (DECL_RTL_SET_P (t))
1836 instantiate_decl_rtl (DECL_RTL (t));
1837 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1838 && DECL_INCOMING_RTL (t))
1839 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1840 if ((VAR_P (t) || TREE_CODE (t) == RESULT_DECL)
1841 && DECL_HAS_VALUE_EXPR_P (t))
1842 {
1843 tree v = DECL_VALUE_EXPR (t);
1844 walk_tree (&v, instantiate_expr, NULL, NULL);
1845 }
1846 }
1847 }
1848 return NULL;
1849 }
1850
1851 /* Subroutine of instantiate_decls: Process all decls in the given
1852 BLOCK node and all its subblocks. */
1853
1854 static void
1855 instantiate_decls_1 (tree let)
1856 {
1857 tree t;
1858
1859 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1860 {
1861 if (DECL_RTL_SET_P (t))
1862 instantiate_decl_rtl (DECL_RTL (t));
1863 if (VAR_P (t) && DECL_HAS_VALUE_EXPR_P (t))
1864 {
1865 tree v = DECL_VALUE_EXPR (t);
1866 walk_tree (&v, instantiate_expr, NULL, NULL);
1867 }
1868 }
1869
1870 /* Process all subblocks. */
1871 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1872 instantiate_decls_1 (t);
1873 }
1874
1875 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1876 all virtual registers in their DECL_RTL's. */
1877
1878 static void
1879 instantiate_decls (tree fndecl)
1880 {
1881 tree decl;
1882 unsigned ix;
1883
1884 /* Process all parameters of the function. */
1885 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1886 {
1887 instantiate_decl_rtl (DECL_RTL (decl));
1888 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1889 if (DECL_HAS_VALUE_EXPR_P (decl))
1890 {
1891 tree v = DECL_VALUE_EXPR (decl);
1892 walk_tree (&v, instantiate_expr, NULL, NULL);
1893 }
1894 }
1895
1896 if ((decl = DECL_RESULT (fndecl))
1897 && TREE_CODE (decl) == RESULT_DECL)
1898 {
1899 if (DECL_RTL_SET_P (decl))
1900 instantiate_decl_rtl (DECL_RTL (decl));
1901 if (DECL_HAS_VALUE_EXPR_P (decl))
1902 {
1903 tree v = DECL_VALUE_EXPR (decl);
1904 walk_tree (&v, instantiate_expr, NULL, NULL);
1905 }
1906 }
1907
1908 /* Process the saved static chain if it exists. */
1909 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1910 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1911 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1912
1913 /* Now process all variables defined in the function or its subblocks. */
1914 if (DECL_INITIAL (fndecl))
1915 instantiate_decls_1 (DECL_INITIAL (fndecl));
1916
1917 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1918 if (DECL_RTL_SET_P (decl))
1919 instantiate_decl_rtl (DECL_RTL (decl));
1920 vec_free (cfun->local_decls);
1921 }
1922
1923 /* Pass through the INSNS of function FNDECL and convert virtual register
1924 references to hard register references. */
1925
1926 static unsigned int
1927 instantiate_virtual_regs (void)
1928 {
1929 rtx_insn *insn;
1930
1931 /* Compute the offsets to use for this function. */
1932 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1933 var_offset = targetm.starting_frame_offset ();
1934 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1935 out_arg_offset = STACK_POINTER_OFFSET;
1936 #ifdef FRAME_POINTER_CFA_OFFSET
1937 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1938 #else
1939 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1940 #endif
1941
1942 /* Initialize recognition, indicating that volatile is OK. */
1943 init_recog ();
1944
1945 /* Scan through all the insns, instantiating every virtual register still
1946 present. */
1947 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1948 if (INSN_P (insn))
1949 {
1950 /* These patterns in the instruction stream can never be recognized.
1951 Fortunately, they shouldn't contain virtual registers either. */
1952 if (GET_CODE (PATTERN (insn)) == USE
1953 || GET_CODE (PATTERN (insn)) == CLOBBER
1954 || GET_CODE (PATTERN (insn)) == ASM_INPUT
1955 || DEBUG_MARKER_INSN_P (insn))
1956 continue;
1957 else if (DEBUG_BIND_INSN_P (insn))
1958 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn));
1959 else
1960 instantiate_virtual_regs_in_insn (insn);
1961
1962 if (insn->deleted ())
1963 continue;
1964
1965 instantiate_virtual_regs_in_rtx (&REG_NOTES (insn));
1966
1967 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1968 if (CALL_P (insn))
1969 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1970 }
1971
1972 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1973 instantiate_decls (current_function_decl);
1974
1975 targetm.instantiate_decls ();
1976
1977 /* Indicate that, from now on, assign_stack_local should use
1978 frame_pointer_rtx. */
1979 virtuals_instantiated = 1;
1980
1981 return 0;
1982 }
1983
1984 namespace {
1985
1986 const pass_data pass_data_instantiate_virtual_regs =
1987 {
1988 RTL_PASS, /* type */
1989 "vregs", /* name */
1990 OPTGROUP_NONE, /* optinfo_flags */
1991 TV_NONE, /* tv_id */
1992 0, /* properties_required */
1993 0, /* properties_provided */
1994 0, /* properties_destroyed */
1995 0, /* todo_flags_start */
1996 0, /* todo_flags_finish */
1997 };
1998
1999 class pass_instantiate_virtual_regs : public rtl_opt_pass
2000 {
2001 public:
2002 pass_instantiate_virtual_regs (gcc::context *ctxt)
2003 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2004 {}
2005
2006 /* opt_pass methods: */
2007 virtual unsigned int execute (function *)
2008 {
2009 return instantiate_virtual_regs ();
2010 }
2011
2012 }; // class pass_instantiate_virtual_regs
2013
2014 } // anon namespace
2015
2016 rtl_opt_pass *
2017 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2018 {
2019 return new pass_instantiate_virtual_regs (ctxt);
2020 }
2021
2022 \f
2023 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2024 This means a type for which function calls must pass an address to the
2025 function or get an address back from the function.
2026 EXP may be a type node or an expression (whose type is tested). */
2027
2028 int
2029 aggregate_value_p (const_tree exp, const_tree fntype)
2030 {
2031 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2032 int i, regno, nregs;
2033 rtx reg;
2034
2035 if (fntype)
2036 switch (TREE_CODE (fntype))
2037 {
2038 case CALL_EXPR:
2039 {
2040 tree fndecl = get_callee_fndecl (fntype);
2041 if (fndecl)
2042 fntype = TREE_TYPE (fndecl);
2043 else if (CALL_EXPR_FN (fntype))
2044 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2045 else
2046 /* For internal functions, assume nothing needs to be
2047 returned in memory. */
2048 return 0;
2049 }
2050 break;
2051 case FUNCTION_DECL:
2052 fntype = TREE_TYPE (fntype);
2053 break;
2054 case FUNCTION_TYPE:
2055 case METHOD_TYPE:
2056 break;
2057 case IDENTIFIER_NODE:
2058 fntype = NULL_TREE;
2059 break;
2060 default:
2061 /* We don't expect other tree types here. */
2062 gcc_unreachable ();
2063 }
2064
2065 if (VOID_TYPE_P (type))
2066 return 0;
2067
2068 /* If a record should be passed the same as its first (and only) member
2069 don't pass it as an aggregate. */
2070 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2071 return aggregate_value_p (first_field (type), fntype);
2072
2073 /* If the front end has decided that this needs to be passed by
2074 reference, do so. */
2075 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2076 && DECL_BY_REFERENCE (exp))
2077 return 1;
2078
2079 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2080 if (fntype && TREE_ADDRESSABLE (fntype))
2081 return 1;
2082
2083 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2084 and thus can't be returned in registers. */
2085 if (TREE_ADDRESSABLE (type))
2086 return 1;
2087
2088 if (TYPE_EMPTY_P (type))
2089 return 0;
2090
2091 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2092 return 1;
2093
2094 if (targetm.calls.return_in_memory (type, fntype))
2095 return 1;
2096
2097 /* Make sure we have suitable call-clobbered regs to return
2098 the value in; if not, we must return it in memory. */
2099 reg = hard_function_value (type, 0, fntype, 0);
2100
2101 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2102 it is OK. */
2103 if (!REG_P (reg))
2104 return 0;
2105
2106 regno = REGNO (reg);
2107 nregs = hard_regno_nregs (regno, TYPE_MODE (type));
2108 for (i = 0; i < nregs; i++)
2109 if (! call_used_regs[regno + i])
2110 return 1;
2111
2112 return 0;
2113 }
2114 \f
2115 /* Return true if we should assign DECL a pseudo register; false if it
2116 should live on the local stack. */
2117
2118 bool
2119 use_register_for_decl (const_tree decl)
2120 {
2121 if (TREE_CODE (decl) == SSA_NAME)
2122 {
2123 /* We often try to use the SSA_NAME, instead of its underlying
2124 decl, to get type information and guide decisions, to avoid
2125 differences of behavior between anonymous and named
2126 variables, but in this one case we have to go for the actual
2127 variable if there is one. The main reason is that, at least
2128 at -O0, we want to place user variables on the stack, but we
2129 don't mind using pseudos for anonymous or ignored temps.
2130 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2131 should go in pseudos, whereas their corresponding variables
2132 might have to go on the stack. So, disregarding the decl
2133 here would negatively impact debug info at -O0, enable
2134 coalescing between SSA_NAMEs that ought to get different
2135 stack/pseudo assignments, and get the incoming argument
2136 processing thoroughly confused by PARM_DECLs expected to live
2137 in stack slots but assigned to pseudos. */
2138 if (!SSA_NAME_VAR (decl))
2139 return TYPE_MODE (TREE_TYPE (decl)) != BLKmode
2140 && !(flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)));
2141
2142 decl = SSA_NAME_VAR (decl);
2143 }
2144
2145 /* Honor volatile. */
2146 if (TREE_SIDE_EFFECTS (decl))
2147 return false;
2148
2149 /* Honor addressability. */
2150 if (TREE_ADDRESSABLE (decl))
2151 return false;
2152
2153 /* RESULT_DECLs are a bit special in that they're assigned without
2154 regard to use_register_for_decl, but we generally only store in
2155 them. If we coalesce their SSA NAMEs, we'd better return a
2156 result that matches the assignment in expand_function_start. */
2157 if (TREE_CODE (decl) == RESULT_DECL)
2158 {
2159 /* If it's not an aggregate, we're going to use a REG or a
2160 PARALLEL containing a REG. */
2161 if (!aggregate_value_p (decl, current_function_decl))
2162 return true;
2163
2164 /* If expand_function_start determines the return value, we'll
2165 use MEM if it's not by reference. */
2166 if (cfun->returns_pcc_struct
2167 || (targetm.calls.struct_value_rtx
2168 (TREE_TYPE (current_function_decl), 1)))
2169 return DECL_BY_REFERENCE (decl);
2170
2171 /* Otherwise, we're taking an extra all.function_result_decl
2172 argument. It's set up in assign_parms_augmented_arg_list,
2173 under the (negated) conditions above, and then it's used to
2174 set up the RESULT_DECL rtl in assign_params, after looping
2175 over all parameters. Now, if the RESULT_DECL is not by
2176 reference, we'll use a MEM either way. */
2177 if (!DECL_BY_REFERENCE (decl))
2178 return false;
2179
2180 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2181 the function_result_decl's assignment. Since it's a pointer,
2182 we can short-circuit a number of the tests below, and we must
2183 duplicat e them because we don't have the
2184 function_result_decl to test. */
2185 if (!targetm.calls.allocate_stack_slots_for_args ())
2186 return true;
2187 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2188 if (optimize)
2189 return true;
2190 /* We don't set DECL_REGISTER for the function_result_decl. */
2191 return false;
2192 }
2193
2194 /* Decl is implicitly addressible by bound stores and loads
2195 if it is an aggregate holding bounds. */
2196 if (chkp_function_instrumented_p (current_function_decl)
2197 && TREE_TYPE (decl)
2198 && !BOUNDED_P (decl)
2199 && chkp_type_has_pointer (TREE_TYPE (decl)))
2200 return false;
2201
2202 /* Only register-like things go in registers. */
2203 if (DECL_MODE (decl) == BLKmode)
2204 return false;
2205
2206 /* If -ffloat-store specified, don't put explicit float variables
2207 into registers. */
2208 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2209 propagates values across these stores, and it probably shouldn't. */
2210 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2211 return false;
2212
2213 if (!targetm.calls.allocate_stack_slots_for_args ())
2214 return true;
2215
2216 /* If we're not interested in tracking debugging information for
2217 this decl, then we can certainly put it in a register. */
2218 if (DECL_IGNORED_P (decl))
2219 return true;
2220
2221 if (optimize)
2222 return true;
2223
2224 if (!DECL_REGISTER (decl))
2225 return false;
2226
2227 /* When not optimizing, disregard register keyword for types that
2228 could have methods, otherwise the methods won't be callable from
2229 the debugger. */
2230 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl)))
2231 return false;
2232
2233 return true;
2234 }
2235
2236 /* Structures to communicate between the subroutines of assign_parms.
2237 The first holds data persistent across all parameters, the second
2238 is cleared out for each parameter. */
2239
2240 struct assign_parm_data_all
2241 {
2242 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2243 should become a job of the target or otherwise encapsulated. */
2244 CUMULATIVE_ARGS args_so_far_v;
2245 cumulative_args_t args_so_far;
2246 struct args_size stack_args_size;
2247 tree function_result_decl;
2248 tree orig_fnargs;
2249 rtx_insn *first_conversion_insn;
2250 rtx_insn *last_conversion_insn;
2251 HOST_WIDE_INT pretend_args_size;
2252 HOST_WIDE_INT extra_pretend_bytes;
2253 int reg_parm_stack_space;
2254 };
2255
2256 struct assign_parm_data_one
2257 {
2258 tree nominal_type;
2259 tree passed_type;
2260 rtx entry_parm;
2261 rtx stack_parm;
2262 machine_mode nominal_mode;
2263 machine_mode passed_mode;
2264 machine_mode promoted_mode;
2265 struct locate_and_pad_arg_data locate;
2266 int partial;
2267 BOOL_BITFIELD named_arg : 1;
2268 BOOL_BITFIELD passed_pointer : 1;
2269 BOOL_BITFIELD on_stack : 1;
2270 BOOL_BITFIELD loaded_in_reg : 1;
2271 };
2272
2273 struct bounds_parm_data
2274 {
2275 assign_parm_data_one parm_data;
2276 tree bounds_parm;
2277 tree ptr_parm;
2278 rtx ptr_entry;
2279 int bound_no;
2280 };
2281
2282 /* A subroutine of assign_parms. Initialize ALL. */
2283
2284 static void
2285 assign_parms_initialize_all (struct assign_parm_data_all *all)
2286 {
2287 tree fntype ATTRIBUTE_UNUSED;
2288
2289 memset (all, 0, sizeof (*all));
2290
2291 fntype = TREE_TYPE (current_function_decl);
2292
2293 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2294 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2295 #else
2296 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2297 current_function_decl, -1);
2298 #endif
2299 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2300
2301 #ifdef INCOMING_REG_PARM_STACK_SPACE
2302 all->reg_parm_stack_space
2303 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2304 #endif
2305 }
2306
2307 /* If ARGS contains entries with complex types, split the entry into two
2308 entries of the component type. Return a new list of substitutions are
2309 needed, else the old list. */
2310
2311 static void
2312 split_complex_args (vec<tree> *args)
2313 {
2314 unsigned i;
2315 tree p;
2316
2317 FOR_EACH_VEC_ELT (*args, i, p)
2318 {
2319 tree type = TREE_TYPE (p);
2320 if (TREE_CODE (type) == COMPLEX_TYPE
2321 && targetm.calls.split_complex_arg (type))
2322 {
2323 tree decl;
2324 tree subtype = TREE_TYPE (type);
2325 bool addressable = TREE_ADDRESSABLE (p);
2326
2327 /* Rewrite the PARM_DECL's type with its component. */
2328 p = copy_node (p);
2329 TREE_TYPE (p) = subtype;
2330 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2331 SET_DECL_MODE (p, VOIDmode);
2332 DECL_SIZE (p) = NULL;
2333 DECL_SIZE_UNIT (p) = NULL;
2334 /* If this arg must go in memory, put it in a pseudo here.
2335 We can't allow it to go in memory as per normal parms,
2336 because the usual place might not have the imag part
2337 adjacent to the real part. */
2338 DECL_ARTIFICIAL (p) = addressable;
2339 DECL_IGNORED_P (p) = addressable;
2340 TREE_ADDRESSABLE (p) = 0;
2341 layout_decl (p, 0);
2342 (*args)[i] = p;
2343
2344 /* Build a second synthetic decl. */
2345 decl = build_decl (EXPR_LOCATION (p),
2346 PARM_DECL, NULL_TREE, subtype);
2347 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2348 DECL_ARTIFICIAL (decl) = addressable;
2349 DECL_IGNORED_P (decl) = addressable;
2350 layout_decl (decl, 0);
2351 args->safe_insert (++i, decl);
2352 }
2353 }
2354 }
2355
2356 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2357 the hidden struct return argument, and (abi willing) complex args.
2358 Return the new parameter list. */
2359
2360 static vec<tree>
2361 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2362 {
2363 tree fndecl = current_function_decl;
2364 tree fntype = TREE_TYPE (fndecl);
2365 vec<tree> fnargs = vNULL;
2366 tree arg;
2367
2368 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2369 fnargs.safe_push (arg);
2370
2371 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2372
2373 /* If struct value address is treated as the first argument, make it so. */
2374 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2375 && ! cfun->returns_pcc_struct
2376 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2377 {
2378 tree type = build_pointer_type (TREE_TYPE (fntype));
2379 tree decl;
2380
2381 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2382 PARM_DECL, get_identifier (".result_ptr"), type);
2383 DECL_ARG_TYPE (decl) = type;
2384 DECL_ARTIFICIAL (decl) = 1;
2385 DECL_NAMELESS (decl) = 1;
2386 TREE_CONSTANT (decl) = 1;
2387 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2388 changes, the end of the RESULT_DECL handling block in
2389 use_register_for_decl must be adjusted to match. */
2390
2391 DECL_CHAIN (decl) = all->orig_fnargs;
2392 all->orig_fnargs = decl;
2393 fnargs.safe_insert (0, decl);
2394
2395 all->function_result_decl = decl;
2396
2397 /* If function is instrumented then bounds of the
2398 passed structure address is the second argument. */
2399 if (chkp_function_instrumented_p (fndecl))
2400 {
2401 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2402 PARM_DECL, get_identifier (".result_bnd"),
2403 pointer_bounds_type_node);
2404 DECL_ARG_TYPE (decl) = pointer_bounds_type_node;
2405 DECL_ARTIFICIAL (decl) = 1;
2406 DECL_NAMELESS (decl) = 1;
2407 TREE_CONSTANT (decl) = 1;
2408
2409 DECL_CHAIN (decl) = DECL_CHAIN (all->orig_fnargs);
2410 DECL_CHAIN (all->orig_fnargs) = decl;
2411 fnargs.safe_insert (1, decl);
2412 }
2413 }
2414
2415 /* If the target wants to split complex arguments into scalars, do so. */
2416 if (targetm.calls.split_complex_arg)
2417 split_complex_args (&fnargs);
2418
2419 return fnargs;
2420 }
2421
2422 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2423 data for the parameter. Incorporate ABI specifics such as pass-by-
2424 reference and type promotion. */
2425
2426 static void
2427 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2428 struct assign_parm_data_one *data)
2429 {
2430 tree nominal_type, passed_type;
2431 machine_mode nominal_mode, passed_mode, promoted_mode;
2432 int unsignedp;
2433
2434 memset (data, 0, sizeof (*data));
2435
2436 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2437 if (!cfun->stdarg)
2438 data->named_arg = 1; /* No variadic parms. */
2439 else if (DECL_CHAIN (parm))
2440 data->named_arg = 1; /* Not the last non-variadic parm. */
2441 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2442 data->named_arg = 1; /* Only variadic ones are unnamed. */
2443 else
2444 data->named_arg = 0; /* Treat as variadic. */
2445
2446 nominal_type = TREE_TYPE (parm);
2447 passed_type = DECL_ARG_TYPE (parm);
2448
2449 /* Look out for errors propagating this far. Also, if the parameter's
2450 type is void then its value doesn't matter. */
2451 if (TREE_TYPE (parm) == error_mark_node
2452 /* This can happen after weird syntax errors
2453 or if an enum type is defined among the parms. */
2454 || TREE_CODE (parm) != PARM_DECL
2455 || passed_type == NULL
2456 || VOID_TYPE_P (nominal_type))
2457 {
2458 nominal_type = passed_type = void_type_node;
2459 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2460 goto egress;
2461 }
2462
2463 /* Find mode of arg as it is passed, and mode of arg as it should be
2464 during execution of this function. */
2465 passed_mode = TYPE_MODE (passed_type);
2466 nominal_mode = TYPE_MODE (nominal_type);
2467
2468 /* If the parm is to be passed as a transparent union or record, use the
2469 type of the first field for the tests below. We have already verified
2470 that the modes are the same. */
2471 if ((TREE_CODE (passed_type) == UNION_TYPE
2472 || TREE_CODE (passed_type) == RECORD_TYPE)
2473 && TYPE_TRANSPARENT_AGGR (passed_type))
2474 passed_type = TREE_TYPE (first_field (passed_type));
2475
2476 /* See if this arg was passed by invisible reference. */
2477 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2478 passed_type, data->named_arg))
2479 {
2480 passed_type = nominal_type = build_pointer_type (passed_type);
2481 data->passed_pointer = true;
2482 passed_mode = nominal_mode = TYPE_MODE (nominal_type);
2483 }
2484
2485 /* Find mode as it is passed by the ABI. */
2486 unsignedp = TYPE_UNSIGNED (passed_type);
2487 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2488 TREE_TYPE (current_function_decl), 0);
2489
2490 egress:
2491 data->nominal_type = nominal_type;
2492 data->passed_type = passed_type;
2493 data->nominal_mode = nominal_mode;
2494 data->passed_mode = passed_mode;
2495 data->promoted_mode = promoted_mode;
2496 }
2497
2498 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2499
2500 static void
2501 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2502 struct assign_parm_data_one *data, bool no_rtl)
2503 {
2504 int varargs_pretend_bytes = 0;
2505
2506 targetm.calls.setup_incoming_varargs (all->args_so_far,
2507 data->promoted_mode,
2508 data->passed_type,
2509 &varargs_pretend_bytes, no_rtl);
2510
2511 /* If the back-end has requested extra stack space, record how much is
2512 needed. Do not change pretend_args_size otherwise since it may be
2513 nonzero from an earlier partial argument. */
2514 if (varargs_pretend_bytes > 0)
2515 all->pretend_args_size = varargs_pretend_bytes;
2516 }
2517
2518 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2519 the incoming location of the current parameter. */
2520
2521 static void
2522 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2523 struct assign_parm_data_one *data)
2524 {
2525 HOST_WIDE_INT pretend_bytes = 0;
2526 rtx entry_parm;
2527 bool in_regs;
2528
2529 if (data->promoted_mode == VOIDmode)
2530 {
2531 data->entry_parm = data->stack_parm = const0_rtx;
2532 return;
2533 }
2534
2535 targetm.calls.warn_parameter_passing_abi (all->args_so_far,
2536 data->passed_type);
2537
2538 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2539 data->promoted_mode,
2540 data->passed_type,
2541 data->named_arg);
2542
2543 if (entry_parm == 0)
2544 data->promoted_mode = data->passed_mode;
2545
2546 /* Determine parm's home in the stack, in case it arrives in the stack
2547 or we should pretend it did. Compute the stack position and rtx where
2548 the argument arrives and its size.
2549
2550 There is one complexity here: If this was a parameter that would
2551 have been passed in registers, but wasn't only because it is
2552 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2553 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2554 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2555 as it was the previous time. */
2556 in_regs = (entry_parm != 0) || POINTER_BOUNDS_TYPE_P (data->passed_type);
2557 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2558 in_regs = true;
2559 #endif
2560 if (!in_regs && !data->named_arg)
2561 {
2562 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2563 {
2564 rtx tem;
2565 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2566 data->promoted_mode,
2567 data->passed_type, true);
2568 in_regs = tem != NULL;
2569 }
2570 }
2571
2572 /* If this parameter was passed both in registers and in the stack, use
2573 the copy on the stack. */
2574 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2575 data->passed_type))
2576 entry_parm = 0;
2577
2578 if (entry_parm)
2579 {
2580 int partial;
2581
2582 partial = targetm.calls.arg_partial_bytes (all->args_so_far,
2583 data->promoted_mode,
2584 data->passed_type,
2585 data->named_arg);
2586 data->partial = partial;
2587
2588 /* The caller might already have allocated stack space for the
2589 register parameters. */
2590 if (partial != 0 && all->reg_parm_stack_space == 0)
2591 {
2592 /* Part of this argument is passed in registers and part
2593 is passed on the stack. Ask the prologue code to extend
2594 the stack part so that we can recreate the full value.
2595
2596 PRETEND_BYTES is the size of the registers we need to store.
2597 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2598 stack space that the prologue should allocate.
2599
2600 Internally, gcc assumes that the argument pointer is aligned
2601 to STACK_BOUNDARY bits. This is used both for alignment
2602 optimizations (see init_emit) and to locate arguments that are
2603 aligned to more than PARM_BOUNDARY bits. We must preserve this
2604 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2605 a stack boundary. */
2606
2607 /* We assume at most one partial arg, and it must be the first
2608 argument on the stack. */
2609 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2610
2611 pretend_bytes = partial;
2612 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2613
2614 /* We want to align relative to the actual stack pointer, so
2615 don't include this in the stack size until later. */
2616 all->extra_pretend_bytes = all->pretend_args_size;
2617 }
2618 }
2619
2620 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2621 all->reg_parm_stack_space,
2622 entry_parm ? data->partial : 0, current_function_decl,
2623 &all->stack_args_size, &data->locate);
2624
2625 /* Update parm_stack_boundary if this parameter is passed in the
2626 stack. */
2627 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2628 crtl->parm_stack_boundary = data->locate.boundary;
2629
2630 /* Adjust offsets to include the pretend args. */
2631 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2632 data->locate.slot_offset.constant += pretend_bytes;
2633 data->locate.offset.constant += pretend_bytes;
2634
2635 data->entry_parm = entry_parm;
2636 }
2637
2638 /* A subroutine of assign_parms. If there is actually space on the stack
2639 for this parm, count it in stack_args_size and return true. */
2640
2641 static bool
2642 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2643 struct assign_parm_data_one *data)
2644 {
2645 /* Bounds are never passed on the stack to keep compatibility
2646 with not instrumented code. */
2647 if (POINTER_BOUNDS_TYPE_P (data->passed_type))
2648 return false;
2649 /* Trivially true if we've no incoming register. */
2650 else if (data->entry_parm == NULL)
2651 ;
2652 /* Also true if we're partially in registers and partially not,
2653 since we've arranged to drop the entire argument on the stack. */
2654 else if (data->partial != 0)
2655 ;
2656 /* Also true if the target says that it's passed in both registers
2657 and on the stack. */
2658 else if (GET_CODE (data->entry_parm) == PARALLEL
2659 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2660 ;
2661 /* Also true if the target says that there's stack allocated for
2662 all register parameters. */
2663 else if (all->reg_parm_stack_space > 0)
2664 ;
2665 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2666 else
2667 return false;
2668
2669 all->stack_args_size.constant += data->locate.size.constant;
2670 if (data->locate.size.var)
2671 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2672
2673 return true;
2674 }
2675
2676 /* A subroutine of assign_parms. Given that this parameter is allocated
2677 stack space by the ABI, find it. */
2678
2679 static void
2680 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2681 {
2682 rtx offset_rtx, stack_parm;
2683 unsigned int align, boundary;
2684
2685 /* If we're passing this arg using a reg, make its stack home the
2686 aligned stack slot. */
2687 if (data->entry_parm)
2688 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2689 else
2690 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2691
2692 stack_parm = crtl->args.internal_arg_pointer;
2693 if (offset_rtx != const0_rtx)
2694 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2695 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2696
2697 if (!data->passed_pointer)
2698 {
2699 set_mem_attributes (stack_parm, parm, 1);
2700 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2701 while promoted mode's size is needed. */
2702 if (data->promoted_mode != BLKmode
2703 && data->promoted_mode != DECL_MODE (parm))
2704 {
2705 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2706 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2707 {
2708 poly_int64 offset = subreg_lowpart_offset (DECL_MODE (parm),
2709 data->promoted_mode);
2710 if (maybe_ne (offset, 0))
2711 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2712 }
2713 }
2714 }
2715
2716 boundary = data->locate.boundary;
2717 align = BITS_PER_UNIT;
2718
2719 /* If we're padding upward, we know that the alignment of the slot
2720 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2721 intentionally forcing upward padding. Otherwise we have to come
2722 up with a guess at the alignment based on OFFSET_RTX. */
2723 if (data->locate.where_pad != PAD_DOWNWARD || data->entry_parm)
2724 align = boundary;
2725 else if (CONST_INT_P (offset_rtx))
2726 {
2727 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2728 align = least_bit_hwi (align);
2729 }
2730 set_mem_align (stack_parm, align);
2731
2732 if (data->entry_parm)
2733 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2734
2735 data->stack_parm = stack_parm;
2736 }
2737
2738 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2739 always valid and contiguous. */
2740
2741 static void
2742 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2743 {
2744 rtx entry_parm = data->entry_parm;
2745 rtx stack_parm = data->stack_parm;
2746
2747 /* If this parm was passed part in regs and part in memory, pretend it
2748 arrived entirely in memory by pushing the register-part onto the stack.
2749 In the special case of a DImode or DFmode that is split, we could put
2750 it together in a pseudoreg directly, but for now that's not worth
2751 bothering with. */
2752 if (data->partial != 0)
2753 {
2754 /* Handle calls that pass values in multiple non-contiguous
2755 locations. The Irix 6 ABI has examples of this. */
2756 if (GET_CODE (entry_parm) == PARALLEL)
2757 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2758 data->passed_type,
2759 int_size_in_bytes (data->passed_type));
2760 else
2761 {
2762 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2763 move_block_from_reg (REGNO (entry_parm),
2764 validize_mem (copy_rtx (stack_parm)),
2765 data->partial / UNITS_PER_WORD);
2766 }
2767
2768 entry_parm = stack_parm;
2769 }
2770
2771 /* If we didn't decide this parm came in a register, by default it came
2772 on the stack. */
2773 else if (entry_parm == NULL)
2774 entry_parm = stack_parm;
2775
2776 /* When an argument is passed in multiple locations, we can't make use
2777 of this information, but we can save some copying if the whole argument
2778 is passed in a single register. */
2779 else if (GET_CODE (entry_parm) == PARALLEL
2780 && data->nominal_mode != BLKmode
2781 && data->passed_mode != BLKmode)
2782 {
2783 size_t i, len = XVECLEN (entry_parm, 0);
2784
2785 for (i = 0; i < len; i++)
2786 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2787 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2788 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2789 == data->passed_mode)
2790 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2791 {
2792 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2793 break;
2794 }
2795 }
2796
2797 data->entry_parm = entry_parm;
2798 }
2799
2800 /* A subroutine of assign_parms. Reconstitute any values which were
2801 passed in multiple registers and would fit in a single register. */
2802
2803 static void
2804 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2805 {
2806 rtx entry_parm = data->entry_parm;
2807
2808 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2809 This can be done with register operations rather than on the
2810 stack, even if we will store the reconstituted parameter on the
2811 stack later. */
2812 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2813 {
2814 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2815 emit_group_store (parmreg, entry_parm, data->passed_type,
2816 GET_MODE_SIZE (GET_MODE (entry_parm)));
2817 entry_parm = parmreg;
2818 }
2819
2820 data->entry_parm = entry_parm;
2821 }
2822
2823 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2824 always valid and properly aligned. */
2825
2826 static void
2827 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2828 {
2829 rtx stack_parm = data->stack_parm;
2830
2831 /* If we can't trust the parm stack slot to be aligned enough for its
2832 ultimate type, don't use that slot after entry. We'll make another
2833 stack slot, if we need one. */
2834 if (stack_parm
2835 && ((STRICT_ALIGNMENT
2836 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2837 || (data->nominal_type
2838 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2839 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2840 stack_parm = NULL;
2841
2842 /* If parm was passed in memory, and we need to convert it on entry,
2843 don't store it back in that same slot. */
2844 else if (data->entry_parm == stack_parm
2845 && data->nominal_mode != BLKmode
2846 && data->nominal_mode != data->passed_mode)
2847 stack_parm = NULL;
2848
2849 /* If stack protection is in effect for this function, don't leave any
2850 pointers in their passed stack slots. */
2851 else if (crtl->stack_protect_guard
2852 && (flag_stack_protect == 2
2853 || data->passed_pointer
2854 || POINTER_TYPE_P (data->nominal_type)))
2855 stack_parm = NULL;
2856
2857 data->stack_parm = stack_parm;
2858 }
2859
2860 /* A subroutine of assign_parms. Return true if the current parameter
2861 should be stored as a BLKmode in the current frame. */
2862
2863 static bool
2864 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2865 {
2866 if (data->nominal_mode == BLKmode)
2867 return true;
2868 if (GET_MODE (data->entry_parm) == BLKmode)
2869 return true;
2870
2871 #ifdef BLOCK_REG_PADDING
2872 /* Only assign_parm_setup_block knows how to deal with register arguments
2873 that are padded at the least significant end. */
2874 if (REG_P (data->entry_parm)
2875 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2876 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2877 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2878 return true;
2879 #endif
2880
2881 return false;
2882 }
2883
2884 /* A subroutine of assign_parms. Arrange for the parameter to be
2885 present and valid in DATA->STACK_RTL. */
2886
2887 static void
2888 assign_parm_setup_block (struct assign_parm_data_all *all,
2889 tree parm, struct assign_parm_data_one *data)
2890 {
2891 rtx entry_parm = data->entry_parm;
2892 rtx stack_parm = data->stack_parm;
2893 rtx target_reg = NULL_RTX;
2894 bool in_conversion_seq = false;
2895 HOST_WIDE_INT size;
2896 HOST_WIDE_INT size_stored;
2897
2898 if (GET_CODE (entry_parm) == PARALLEL)
2899 entry_parm = emit_group_move_into_temps (entry_parm);
2900
2901 /* If we want the parameter in a pseudo, don't use a stack slot. */
2902 if (is_gimple_reg (parm) && use_register_for_decl (parm))
2903 {
2904 tree def = ssa_default_def (cfun, parm);
2905 gcc_assert (def);
2906 machine_mode mode = promote_ssa_mode (def, NULL);
2907 rtx reg = gen_reg_rtx (mode);
2908 if (GET_CODE (reg) != CONCAT)
2909 stack_parm = reg;
2910 else
2911 {
2912 target_reg = reg;
2913 /* Avoid allocating a stack slot, if there isn't one
2914 preallocated by the ABI. It might seem like we should
2915 always prefer a pseudo, but converting between
2916 floating-point and integer modes goes through the stack
2917 on various machines, so it's better to use the reserved
2918 stack slot than to risk wasting it and allocating more
2919 for the conversion. */
2920 if (stack_parm == NULL_RTX)
2921 {
2922 int save = generating_concat_p;
2923 generating_concat_p = 0;
2924 stack_parm = gen_reg_rtx (mode);
2925 generating_concat_p = save;
2926 }
2927 }
2928 data->stack_parm = NULL;
2929 }
2930
2931 size = int_size_in_bytes (data->passed_type);
2932 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2933 if (stack_parm == 0)
2934 {
2935 SET_DECL_ALIGN (parm, MAX (DECL_ALIGN (parm), BITS_PER_WORD));
2936 stack_parm = assign_stack_local (BLKmode, size_stored,
2937 DECL_ALIGN (parm));
2938 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2939 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2940 set_mem_attributes (stack_parm, parm, 1);
2941 }
2942
2943 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2944 calls that pass values in multiple non-contiguous locations. */
2945 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2946 {
2947 rtx mem;
2948
2949 /* Note that we will be storing an integral number of words.
2950 So we have to be careful to ensure that we allocate an
2951 integral number of words. We do this above when we call
2952 assign_stack_local if space was not allocated in the argument
2953 list. If it was, this will not work if PARM_BOUNDARY is not
2954 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2955 if it becomes a problem. Exception is when BLKmode arrives
2956 with arguments not conforming to word_mode. */
2957
2958 if (data->stack_parm == 0)
2959 ;
2960 else if (GET_CODE (entry_parm) == PARALLEL)
2961 ;
2962 else
2963 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2964
2965 mem = validize_mem (copy_rtx (stack_parm));
2966
2967 /* Handle values in multiple non-contiguous locations. */
2968 if (GET_CODE (entry_parm) == PARALLEL && !MEM_P (mem))
2969 emit_group_store (mem, entry_parm, data->passed_type, size);
2970 else if (GET_CODE (entry_parm) == PARALLEL)
2971 {
2972 push_to_sequence2 (all->first_conversion_insn,
2973 all->last_conversion_insn);
2974 emit_group_store (mem, entry_parm, data->passed_type, size);
2975 all->first_conversion_insn = get_insns ();
2976 all->last_conversion_insn = get_last_insn ();
2977 end_sequence ();
2978 in_conversion_seq = true;
2979 }
2980
2981 else if (size == 0)
2982 ;
2983
2984 /* If SIZE is that of a mode no bigger than a word, just use
2985 that mode's store operation. */
2986 else if (size <= UNITS_PER_WORD)
2987 {
2988 unsigned int bits = size * BITS_PER_UNIT;
2989 machine_mode mode = int_mode_for_size (bits, 0).else_blk ();
2990
2991 if (mode != BLKmode
2992 #ifdef BLOCK_REG_PADDING
2993 && (size == UNITS_PER_WORD
2994 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2995 != (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2996 #endif
2997 )
2998 {
2999 rtx reg;
3000
3001 /* We are really truncating a word_mode value containing
3002 SIZE bytes into a value of mode MODE. If such an
3003 operation requires no actual instructions, we can refer
3004 to the value directly in mode MODE, otherwise we must
3005 start with the register in word_mode and explicitly
3006 convert it. */
3007 if (targetm.truly_noop_truncation (size * BITS_PER_UNIT,
3008 BITS_PER_WORD))
3009 reg = gen_rtx_REG (mode, REGNO (entry_parm));
3010 else
3011 {
3012 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3013 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
3014 }
3015 emit_move_insn (change_address (mem, mode, 0), reg);
3016 }
3017
3018 #ifdef BLOCK_REG_PADDING
3019 /* Storing the register in memory as a full word, as
3020 move_block_from_reg below would do, and then using the
3021 MEM in a smaller mode, has the effect of shifting right
3022 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3023 shifting must be explicit. */
3024 else if (!MEM_P (mem))
3025 {
3026 rtx x;
3027
3028 /* If the assert below fails, we should have taken the
3029 mode != BLKmode path above, unless we have downward
3030 padding of smaller-than-word arguments on a machine
3031 with little-endian bytes, which would likely require
3032 additional changes to work correctly. */
3033 gcc_checking_assert (BYTES_BIG_ENDIAN
3034 && (BLOCK_REG_PADDING (mode,
3035 data->passed_type, 1)
3036 == PAD_UPWARD));
3037
3038 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3039
3040 x = gen_rtx_REG (word_mode, REGNO (entry_parm));
3041 x = expand_shift (RSHIFT_EXPR, word_mode, x, by,
3042 NULL_RTX, 1);
3043 x = force_reg (word_mode, x);
3044 x = gen_lowpart_SUBREG (GET_MODE (mem), x);
3045
3046 emit_move_insn (mem, x);
3047 }
3048 #endif
3049
3050 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3051 machine must be aligned to the left before storing
3052 to memory. Note that the previous test doesn't
3053 handle all cases (e.g. SIZE == 3). */
3054 else if (size != UNITS_PER_WORD
3055 #ifdef BLOCK_REG_PADDING
3056 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
3057 == PAD_DOWNWARD)
3058 #else
3059 && BYTES_BIG_ENDIAN
3060 #endif
3061 )
3062 {
3063 rtx tem, x;
3064 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3065 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3066
3067 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
3068 tem = change_address (mem, word_mode, 0);
3069 emit_move_insn (tem, x);
3070 }
3071 else
3072 move_block_from_reg (REGNO (entry_parm), mem,
3073 size_stored / UNITS_PER_WORD);
3074 }
3075 else if (!MEM_P (mem))
3076 {
3077 gcc_checking_assert (size > UNITS_PER_WORD);
3078 #ifdef BLOCK_REG_PADDING
3079 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem),
3080 data->passed_type, 0)
3081 == PAD_UPWARD);
3082 #endif
3083 emit_move_insn (mem, entry_parm);
3084 }
3085 else
3086 move_block_from_reg (REGNO (entry_parm), mem,
3087 size_stored / UNITS_PER_WORD);
3088 }
3089 else if (data->stack_parm == 0)
3090 {
3091 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3092 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
3093 BLOCK_OP_NORMAL);
3094 all->first_conversion_insn = get_insns ();
3095 all->last_conversion_insn = get_last_insn ();
3096 end_sequence ();
3097 in_conversion_seq = true;
3098 }
3099
3100 if (target_reg)
3101 {
3102 if (!in_conversion_seq)
3103 emit_move_insn (target_reg, stack_parm);
3104 else
3105 {
3106 push_to_sequence2 (all->first_conversion_insn,
3107 all->last_conversion_insn);
3108 emit_move_insn (target_reg, stack_parm);
3109 all->first_conversion_insn = get_insns ();
3110 all->last_conversion_insn = get_last_insn ();
3111 end_sequence ();
3112 }
3113 stack_parm = target_reg;
3114 }
3115
3116 data->stack_parm = stack_parm;
3117 set_parm_rtl (parm, stack_parm);
3118 }
3119
3120 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3121 parameter. Get it there. Perform all ABI specified conversions. */
3122
3123 static void
3124 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
3125 struct assign_parm_data_one *data)
3126 {
3127 rtx parmreg, validated_mem;
3128 rtx equiv_stack_parm;
3129 machine_mode promoted_nominal_mode;
3130 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
3131 bool did_conversion = false;
3132 bool need_conversion, moved;
3133 rtx rtl;
3134
3135 /* Store the parm in a pseudoregister during the function, but we may
3136 need to do it in a wider mode. Using 2 here makes the result
3137 consistent with promote_decl_mode and thus expand_expr_real_1. */
3138 promoted_nominal_mode
3139 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
3140 TREE_TYPE (current_function_decl), 2);
3141
3142 parmreg = gen_reg_rtx (promoted_nominal_mode);
3143 if (!DECL_ARTIFICIAL (parm))
3144 mark_user_reg (parmreg);
3145
3146 /* If this was an item that we received a pointer to,
3147 set rtl appropriately. */
3148 if (data->passed_pointer)
3149 {
3150 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
3151 set_mem_attributes (rtl, parm, 1);
3152 }
3153 else
3154 rtl = parmreg;
3155
3156 assign_parm_remove_parallels (data);
3157
3158 /* Copy the value into the register, thus bridging between
3159 assign_parm_find_data_types and expand_expr_real_1. */
3160
3161 equiv_stack_parm = data->stack_parm;
3162 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3163
3164 need_conversion = (data->nominal_mode != data->passed_mode
3165 || promoted_nominal_mode != data->promoted_mode);
3166 moved = false;
3167
3168 if (need_conversion
3169 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3170 && data->nominal_mode == data->passed_mode
3171 && data->nominal_mode == GET_MODE (data->entry_parm))
3172 {
3173 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3174 mode, by the caller. We now have to convert it to
3175 NOMINAL_MODE, if different. However, PARMREG may be in
3176 a different mode than NOMINAL_MODE if it is being stored
3177 promoted.
3178
3179 If ENTRY_PARM is a hard register, it might be in a register
3180 not valid for operating in its mode (e.g., an odd-numbered
3181 register for a DFmode). In that case, moves are the only
3182 thing valid, so we can't do a convert from there. This
3183 occurs when the calling sequence allow such misaligned
3184 usages.
3185
3186 In addition, the conversion may involve a call, which could
3187 clobber parameters which haven't been copied to pseudo
3188 registers yet.
3189
3190 First, we try to emit an insn which performs the necessary
3191 conversion. We verify that this insn does not clobber any
3192 hard registers. */
3193
3194 enum insn_code icode;
3195 rtx op0, op1;
3196
3197 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3198 unsignedp);
3199
3200 op0 = parmreg;
3201 op1 = validated_mem;
3202 if (icode != CODE_FOR_nothing
3203 && insn_operand_matches (icode, 0, op0)
3204 && insn_operand_matches (icode, 1, op1))
3205 {
3206 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3207 rtx_insn *insn, *insns;
3208 rtx t = op1;
3209 HARD_REG_SET hardregs;
3210
3211 start_sequence ();
3212 /* If op1 is a hard register that is likely spilled, first
3213 force it into a pseudo, otherwise combiner might extend
3214 its lifetime too much. */
3215 if (GET_CODE (t) == SUBREG)
3216 t = SUBREG_REG (t);
3217 if (REG_P (t)
3218 && HARD_REGISTER_P (t)
3219 && ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
3220 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
3221 {
3222 t = gen_reg_rtx (GET_MODE (op1));
3223 emit_move_insn (t, op1);
3224 }
3225 else
3226 t = op1;
3227 rtx_insn *pat = gen_extend_insn (op0, t, promoted_nominal_mode,
3228 data->passed_mode, unsignedp);
3229 emit_insn (pat);
3230 insns = get_insns ();
3231
3232 moved = true;
3233 CLEAR_HARD_REG_SET (hardregs);
3234 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3235 {
3236 if (INSN_P (insn))
3237 note_stores (PATTERN (insn), record_hard_reg_sets,
3238 &hardregs);
3239 if (!hard_reg_set_empty_p (hardregs))
3240 moved = false;
3241 }
3242
3243 end_sequence ();
3244
3245 if (moved)
3246 {
3247 emit_insn (insns);
3248 if (equiv_stack_parm != NULL_RTX)
3249 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3250 equiv_stack_parm);
3251 }
3252 }
3253 }
3254
3255 if (moved)
3256 /* Nothing to do. */
3257 ;
3258 else if (need_conversion)
3259 {
3260 /* We did not have an insn to convert directly, or the sequence
3261 generated appeared unsafe. We must first copy the parm to a
3262 pseudo reg, and save the conversion until after all
3263 parameters have been moved. */
3264
3265 int save_tree_used;
3266 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3267
3268 emit_move_insn (tempreg, validated_mem);
3269
3270 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3271 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3272
3273 if (partial_subreg_p (tempreg)
3274 && GET_MODE (tempreg) == data->nominal_mode
3275 && REG_P (SUBREG_REG (tempreg))
3276 && data->nominal_mode == data->passed_mode
3277 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm))
3278 {
3279 /* The argument is already sign/zero extended, so note it
3280 into the subreg. */
3281 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3282 SUBREG_PROMOTED_SET (tempreg, unsignedp);
3283 }
3284
3285 /* TREE_USED gets set erroneously during expand_assignment. */
3286 save_tree_used = TREE_USED (parm);
3287 SET_DECL_RTL (parm, rtl);
3288 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3289 SET_DECL_RTL (parm, NULL_RTX);
3290 TREE_USED (parm) = save_tree_used;
3291 all->first_conversion_insn = get_insns ();
3292 all->last_conversion_insn = get_last_insn ();
3293 end_sequence ();
3294
3295 did_conversion = true;
3296 }
3297 else
3298 emit_move_insn (parmreg, validated_mem);
3299
3300 /* If we were passed a pointer but the actual value can safely live
3301 in a register, retrieve it and use it directly. */
3302 if (data->passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3303 {
3304 /* We can't use nominal_mode, because it will have been set to
3305 Pmode above. We must use the actual mode of the parm. */
3306 if (use_register_for_decl (parm))
3307 {
3308 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3309 mark_user_reg (parmreg);
3310 }
3311 else
3312 {
3313 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3314 TYPE_MODE (TREE_TYPE (parm)),
3315 TYPE_ALIGN (TREE_TYPE (parm)));
3316 parmreg
3317 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3318 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3319 align);
3320 set_mem_attributes (parmreg, parm, 1);
3321 }
3322
3323 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3324 the debug info in case it is not legitimate. */
3325 if (GET_MODE (parmreg) != GET_MODE (rtl))
3326 {
3327 rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
3328 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3329
3330 push_to_sequence2 (all->first_conversion_insn,
3331 all->last_conversion_insn);
3332 emit_move_insn (tempreg, rtl);
3333 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3334 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
3335 tempreg);
3336 all->first_conversion_insn = get_insns ();
3337 all->last_conversion_insn = get_last_insn ();
3338 end_sequence ();
3339
3340 did_conversion = true;
3341 }
3342 else
3343 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
3344
3345 rtl = parmreg;
3346
3347 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3348 now the parm. */
3349 data->stack_parm = NULL;
3350 }
3351
3352 set_parm_rtl (parm, rtl);
3353
3354 /* Mark the register as eliminable if we did no conversion and it was
3355 copied from memory at a fixed offset, and the arg pointer was not
3356 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3357 offset formed an invalid address, such memory-equivalences as we
3358 make here would screw up life analysis for it. */
3359 if (data->nominal_mode == data->passed_mode
3360 && !did_conversion
3361 && data->stack_parm != 0
3362 && MEM_P (data->stack_parm)
3363 && data->locate.offset.var == 0
3364 && reg_mentioned_p (virtual_incoming_args_rtx,
3365 XEXP (data->stack_parm, 0)))
3366 {
3367 rtx_insn *linsn = get_last_insn ();
3368 rtx_insn *sinsn;
3369 rtx set;
3370
3371 /* Mark complex types separately. */
3372 if (GET_CODE (parmreg) == CONCAT)
3373 {
3374 scalar_mode submode = GET_MODE_INNER (GET_MODE (parmreg));
3375 int regnor = REGNO (XEXP (parmreg, 0));
3376 int regnoi = REGNO (XEXP (parmreg, 1));
3377 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3378 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3379 GET_MODE_SIZE (submode));
3380
3381 /* Scan backwards for the set of the real and
3382 imaginary parts. */
3383 for (sinsn = linsn; sinsn != 0;
3384 sinsn = prev_nonnote_insn (sinsn))
3385 {
3386 set = single_set (sinsn);
3387 if (set == 0)
3388 continue;
3389
3390 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3391 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3392 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3393 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3394 }
3395 }
3396 else
3397 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3398 }
3399
3400 /* For pointer data type, suggest pointer register. */
3401 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3402 mark_reg_pointer (parmreg,
3403 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3404 }
3405
3406 /* A subroutine of assign_parms. Allocate stack space to hold the current
3407 parameter. Get it there. Perform all ABI specified conversions. */
3408
3409 static void
3410 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3411 struct assign_parm_data_one *data)
3412 {
3413 /* Value must be stored in the stack slot STACK_PARM during function
3414 execution. */
3415 bool to_conversion = false;
3416
3417 assign_parm_remove_parallels (data);
3418
3419 if (data->promoted_mode != data->nominal_mode)
3420 {
3421 /* Conversion is required. */
3422 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3423
3424 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3425
3426 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3427 to_conversion = true;
3428
3429 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3430 TYPE_UNSIGNED (TREE_TYPE (parm)));
3431
3432 if (data->stack_parm)
3433 {
3434 poly_int64 offset
3435 = subreg_lowpart_offset (data->nominal_mode,
3436 GET_MODE (data->stack_parm));
3437 /* ??? This may need a big-endian conversion on sparc64. */
3438 data->stack_parm
3439 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3440 if (maybe_ne (offset, 0) && MEM_OFFSET_KNOWN_P (data->stack_parm))
3441 set_mem_offset (data->stack_parm,
3442 MEM_OFFSET (data->stack_parm) + offset);
3443 }
3444 }
3445
3446 if (data->entry_parm != data->stack_parm)
3447 {
3448 rtx src, dest;
3449
3450 if (data->stack_parm == 0)
3451 {
3452 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3453 GET_MODE (data->entry_parm),
3454 TYPE_ALIGN (data->passed_type));
3455 data->stack_parm
3456 = assign_stack_local (GET_MODE (data->entry_parm),
3457 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3458 align);
3459 set_mem_attributes (data->stack_parm, parm, 1);
3460 }
3461
3462 dest = validize_mem (copy_rtx (data->stack_parm));
3463 src = validize_mem (copy_rtx (data->entry_parm));
3464
3465 if (MEM_P (src))
3466 {
3467 /* Use a block move to handle potentially misaligned entry_parm. */
3468 if (!to_conversion)
3469 push_to_sequence2 (all->first_conversion_insn,
3470 all->last_conversion_insn);
3471 to_conversion = true;
3472
3473 emit_block_move (dest, src,
3474 GEN_INT (int_size_in_bytes (data->passed_type)),
3475 BLOCK_OP_NORMAL);
3476 }
3477 else
3478 {
3479 if (!REG_P (src))
3480 src = force_reg (GET_MODE (src), src);
3481 emit_move_insn (dest, src);
3482 }
3483 }
3484
3485 if (to_conversion)
3486 {
3487 all->first_conversion_insn = get_insns ();
3488 all->last_conversion_insn = get_last_insn ();
3489 end_sequence ();
3490 }
3491
3492 set_parm_rtl (parm, data->stack_parm);
3493 }
3494
3495 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3496 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3497
3498 static void
3499 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3500 vec<tree> fnargs)
3501 {
3502 tree parm;
3503 tree orig_fnargs = all->orig_fnargs;
3504 unsigned i = 0;
3505
3506 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3507 {
3508 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3509 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3510 {
3511 rtx tmp, real, imag;
3512 scalar_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3513
3514 real = DECL_RTL (fnargs[i]);
3515 imag = DECL_RTL (fnargs[i + 1]);
3516 if (inner != GET_MODE (real))
3517 {
3518 real = gen_lowpart_SUBREG (inner, real);
3519 imag = gen_lowpart_SUBREG (inner, imag);
3520 }
3521
3522 if (TREE_ADDRESSABLE (parm))
3523 {
3524 rtx rmem, imem;
3525 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3526 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3527 DECL_MODE (parm),
3528 TYPE_ALIGN (TREE_TYPE (parm)));
3529
3530 /* split_complex_arg put the real and imag parts in
3531 pseudos. Move them to memory. */
3532 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3533 set_mem_attributes (tmp, parm, 1);
3534 rmem = adjust_address_nv (tmp, inner, 0);
3535 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3536 push_to_sequence2 (all->first_conversion_insn,
3537 all->last_conversion_insn);
3538 emit_move_insn (rmem, real);
3539 emit_move_insn (imem, imag);
3540 all->first_conversion_insn = get_insns ();
3541 all->last_conversion_insn = get_last_insn ();
3542 end_sequence ();
3543 }
3544 else
3545 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3546 set_parm_rtl (parm, tmp);
3547
3548 real = DECL_INCOMING_RTL (fnargs[i]);
3549 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3550 if (inner != GET_MODE (real))
3551 {
3552 real = gen_lowpart_SUBREG (inner, real);
3553 imag = gen_lowpart_SUBREG (inner, imag);
3554 }
3555 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3556 set_decl_incoming_rtl (parm, tmp, false);
3557 i++;
3558 }
3559 }
3560 }
3561
3562 /* Load bounds of PARM from bounds table. */
3563 static void
3564 assign_parm_load_bounds (struct assign_parm_data_one *data,
3565 tree parm,
3566 rtx entry,
3567 unsigned bound_no)
3568 {
3569 bitmap_iterator bi;
3570 unsigned i, offs = 0;
3571 int bnd_no = -1;
3572 rtx slot = NULL, ptr = NULL;
3573
3574 if (parm)
3575 {
3576 bitmap slots;
3577 bitmap_obstack_initialize (NULL);
3578 slots = BITMAP_ALLOC (NULL);
3579 chkp_find_bound_slots (TREE_TYPE (parm), slots);
3580 EXECUTE_IF_SET_IN_BITMAP (slots, 0, i, bi)
3581 {
3582 if (bound_no)
3583 bound_no--;
3584 else
3585 {
3586 bnd_no = i;
3587 break;
3588 }
3589 }
3590 BITMAP_FREE (slots);
3591 bitmap_obstack_release (NULL);
3592 }
3593
3594 /* We may have bounds not associated with any pointer. */
3595 if (bnd_no != -1)
3596 offs = bnd_no * POINTER_SIZE / BITS_PER_UNIT;
3597
3598 /* Find associated pointer. */
3599 if (bnd_no == -1)
3600 {
3601 /* If bounds are not associated with any bounds,
3602 then it is passed in a register or special slot. */
3603 gcc_assert (data->entry_parm);
3604 ptr = const0_rtx;
3605 }
3606 else if (MEM_P (entry))
3607 slot = adjust_address (entry, Pmode, offs);
3608 else if (REG_P (entry))
3609 ptr = gen_rtx_REG (Pmode, REGNO (entry) + bnd_no);
3610 else if (GET_CODE (entry) == PARALLEL)
3611 ptr = chkp_get_value_with_offs (entry, GEN_INT (offs));
3612 else
3613 gcc_unreachable ();
3614 data->entry_parm = targetm.calls.load_bounds_for_arg (slot, ptr,
3615 data->entry_parm);
3616 }
3617
3618 /* Assign RTL expressions to the function's bounds parameters BNDARGS. */
3619
3620 static void
3621 assign_bounds (vec<bounds_parm_data> &bndargs,
3622 struct assign_parm_data_all &all,
3623 bool assign_regs, bool assign_special,
3624 bool assign_bt)
3625 {
3626 unsigned i, pass;
3627 bounds_parm_data *pbdata;
3628
3629 if (!bndargs.exists ())
3630 return;
3631
3632 /* We make few passes to store input bounds. Firstly handle bounds
3633 passed in registers. After that we load bounds passed in special
3634 slots. Finally we load bounds from Bounds Table. */
3635 for (pass = 0; pass < 3; pass++)
3636 FOR_EACH_VEC_ELT (bndargs, i, pbdata)
3637 {
3638 /* Pass 0 => regs only. */
3639 if (pass == 0
3640 && (!assign_regs
3641 ||(!pbdata->parm_data.entry_parm
3642 || GET_CODE (pbdata->parm_data.entry_parm) != REG)))
3643 continue;
3644 /* Pass 1 => slots only. */
3645 else if (pass == 1
3646 && (!assign_special
3647 || (!pbdata->parm_data.entry_parm
3648 || GET_CODE (pbdata->parm_data.entry_parm) == REG)))
3649 continue;
3650 /* Pass 2 => BT only. */
3651 else if (pass == 2
3652 && (!assign_bt
3653 || pbdata->parm_data.entry_parm))
3654 continue;
3655
3656 if (!pbdata->parm_data.entry_parm
3657 || GET_CODE (pbdata->parm_data.entry_parm) != REG)
3658 assign_parm_load_bounds (&pbdata->parm_data, pbdata->ptr_parm,
3659 pbdata->ptr_entry, pbdata->bound_no);
3660
3661 set_decl_incoming_rtl (pbdata->bounds_parm,
3662 pbdata->parm_data.entry_parm, false);
3663
3664 if (assign_parm_setup_block_p (&pbdata->parm_data))
3665 assign_parm_setup_block (&all, pbdata->bounds_parm,
3666 &pbdata->parm_data);
3667 else if (pbdata->parm_data.passed_pointer
3668 || use_register_for_decl (pbdata->bounds_parm))
3669 assign_parm_setup_reg (&all, pbdata->bounds_parm,
3670 &pbdata->parm_data);
3671 else
3672 assign_parm_setup_stack (&all, pbdata->bounds_parm,
3673 &pbdata->parm_data);
3674 }
3675 }
3676
3677 /* Assign RTL expressions to the function's parameters. This may involve
3678 copying them into registers and using those registers as the DECL_RTL. */
3679
3680 static void
3681 assign_parms (tree fndecl)
3682 {
3683 struct assign_parm_data_all all;
3684 tree parm;
3685 vec<tree> fnargs;
3686 unsigned i, bound_no = 0;
3687 tree last_arg = NULL;
3688 rtx last_arg_entry = NULL;
3689 vec<bounds_parm_data> bndargs = vNULL;
3690 bounds_parm_data bdata;
3691
3692 crtl->args.internal_arg_pointer
3693 = targetm.calls.internal_arg_pointer ();
3694
3695 assign_parms_initialize_all (&all);
3696 fnargs = assign_parms_augmented_arg_list (&all);
3697
3698 FOR_EACH_VEC_ELT (fnargs, i, parm)
3699 {
3700 struct assign_parm_data_one data;
3701
3702 /* Extract the type of PARM; adjust it according to ABI. */
3703 assign_parm_find_data_types (&all, parm, &data);
3704
3705 /* Early out for errors and void parameters. */
3706 if (data.passed_mode == VOIDmode)
3707 {
3708 SET_DECL_RTL (parm, const0_rtx);
3709 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3710 continue;
3711 }
3712
3713 /* Estimate stack alignment from parameter alignment. */
3714 if (SUPPORTS_STACK_ALIGNMENT)
3715 {
3716 unsigned int align
3717 = targetm.calls.function_arg_boundary (data.promoted_mode,
3718 data.passed_type);
3719 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3720 align);
3721 if (TYPE_ALIGN (data.nominal_type) > align)
3722 align = MINIMUM_ALIGNMENT (data.nominal_type,
3723 TYPE_MODE (data.nominal_type),
3724 TYPE_ALIGN (data.nominal_type));
3725 if (crtl->stack_alignment_estimated < align)
3726 {
3727 gcc_assert (!crtl->stack_realign_processed);
3728 crtl->stack_alignment_estimated = align;
3729 }
3730 }
3731
3732 /* Find out where the parameter arrives in this function. */
3733 assign_parm_find_entry_rtl (&all, &data);
3734
3735 /* Find out where stack space for this parameter might be. */
3736 if (assign_parm_is_stack_parm (&all, &data))
3737 {
3738 assign_parm_find_stack_rtl (parm, &data);
3739 assign_parm_adjust_entry_rtl (&data);
3740 }
3741 if (!POINTER_BOUNDS_TYPE_P (data.passed_type))
3742 {
3743 /* Remember where last non bounds arg was passed in case
3744 we have to load associated bounds for it from Bounds
3745 Table. */
3746 last_arg = parm;
3747 last_arg_entry = data.entry_parm;
3748 bound_no = 0;
3749 }
3750 /* Record permanently how this parm was passed. */
3751 if (data.passed_pointer)
3752 {
3753 rtx incoming_rtl
3754 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3755 data.entry_parm);
3756 set_decl_incoming_rtl (parm, incoming_rtl, true);
3757 }
3758 else
3759 set_decl_incoming_rtl (parm, data.entry_parm, false);
3760
3761 assign_parm_adjust_stack_rtl (&data);
3762
3763 /* Bounds should be loaded in the particular order to
3764 have registers allocated correctly. Collect info about
3765 input bounds and load them later. */
3766 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3767 {
3768 /* Expect bounds in instrumented functions only. */
3769 gcc_assert (chkp_function_instrumented_p (fndecl));
3770
3771 bdata.parm_data = data;
3772 bdata.bounds_parm = parm;
3773 bdata.ptr_parm = last_arg;
3774 bdata.ptr_entry = last_arg_entry;
3775 bdata.bound_no = bound_no;
3776 bndargs.safe_push (bdata);
3777 }
3778 else
3779 {
3780 if (assign_parm_setup_block_p (&data))
3781 assign_parm_setup_block (&all, parm, &data);
3782 else if (data.passed_pointer || use_register_for_decl (parm))
3783 assign_parm_setup_reg (&all, parm, &data);
3784 else
3785 assign_parm_setup_stack (&all, parm, &data);
3786 }
3787
3788 if (cfun->stdarg && !DECL_CHAIN (parm))
3789 {
3790 int pretend_bytes = 0;
3791
3792 assign_parms_setup_varargs (&all, &data, false);
3793
3794 if (chkp_function_instrumented_p (fndecl))
3795 {
3796 /* We expect this is the last parm. Otherwise it is wrong
3797 to assign bounds right now. */
3798 gcc_assert (i == (fnargs.length () - 1));
3799 assign_bounds (bndargs, all, true, false, false);
3800 targetm.calls.setup_incoming_vararg_bounds (all.args_so_far,
3801 data.promoted_mode,
3802 data.passed_type,
3803 &pretend_bytes,
3804 false);
3805 assign_bounds (bndargs, all, false, true, true);
3806 bndargs.release ();
3807 }
3808 }
3809
3810 /* Update info on where next arg arrives in registers. */
3811 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3812 data.passed_type, data.named_arg);
3813
3814 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3815 bound_no++;
3816 }
3817
3818 assign_bounds (bndargs, all, true, true, true);
3819 bndargs.release ();
3820
3821 if (targetm.calls.split_complex_arg)
3822 assign_parms_unsplit_complex (&all, fnargs);
3823
3824 fnargs.release ();
3825
3826 /* Output all parameter conversion instructions (possibly including calls)
3827 now that all parameters have been copied out of hard registers. */
3828 emit_insn (all.first_conversion_insn);
3829
3830 /* Estimate reload stack alignment from scalar return mode. */
3831 if (SUPPORTS_STACK_ALIGNMENT)
3832 {
3833 if (DECL_RESULT (fndecl))
3834 {
3835 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3836 machine_mode mode = TYPE_MODE (type);
3837
3838 if (mode != BLKmode
3839 && mode != VOIDmode
3840 && !AGGREGATE_TYPE_P (type))
3841 {
3842 unsigned int align = GET_MODE_ALIGNMENT (mode);
3843 if (crtl->stack_alignment_estimated < align)
3844 {
3845 gcc_assert (!crtl->stack_realign_processed);
3846 crtl->stack_alignment_estimated = align;
3847 }
3848 }
3849 }
3850 }
3851
3852 /* If we are receiving a struct value address as the first argument, set up
3853 the RTL for the function result. As this might require code to convert
3854 the transmitted address to Pmode, we do this here to ensure that possible
3855 preliminary conversions of the address have been emitted already. */
3856 if (all.function_result_decl)
3857 {
3858 tree result = DECL_RESULT (current_function_decl);
3859 rtx addr = DECL_RTL (all.function_result_decl);
3860 rtx x;
3861
3862 if (DECL_BY_REFERENCE (result))
3863 {
3864 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3865 x = addr;
3866 }
3867 else
3868 {
3869 SET_DECL_VALUE_EXPR (result,
3870 build1 (INDIRECT_REF, TREE_TYPE (result),
3871 all.function_result_decl));
3872 addr = convert_memory_address (Pmode, addr);
3873 x = gen_rtx_MEM (DECL_MODE (result), addr);
3874 set_mem_attributes (x, result, 1);
3875 }
3876
3877 DECL_HAS_VALUE_EXPR_P (result) = 1;
3878
3879 set_parm_rtl (result, x);
3880 }
3881
3882 /* We have aligned all the args, so add space for the pretend args. */
3883 crtl->args.pretend_args_size = all.pretend_args_size;
3884 all.stack_args_size.constant += all.extra_pretend_bytes;
3885 crtl->args.size = all.stack_args_size.constant;
3886
3887 /* Adjust function incoming argument size for alignment and
3888 minimum length. */
3889
3890 crtl->args.size = MAX (crtl->args.size, all.reg_parm_stack_space);
3891 crtl->args.size = CEIL_ROUND (crtl->args.size,
3892 PARM_BOUNDARY / BITS_PER_UNIT);
3893
3894 if (ARGS_GROW_DOWNWARD)
3895 {
3896 crtl->args.arg_offset_rtx
3897 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3898 : expand_expr (size_diffop (all.stack_args_size.var,
3899 size_int (-all.stack_args_size.constant)),
3900 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3901 }
3902 else
3903 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3904
3905 /* See how many bytes, if any, of its args a function should try to pop
3906 on return. */
3907
3908 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3909 TREE_TYPE (fndecl),
3910 crtl->args.size);
3911
3912 /* For stdarg.h function, save info about
3913 regs and stack space used by the named args. */
3914
3915 crtl->args.info = all.args_so_far_v;
3916
3917 /* Set the rtx used for the function return value. Put this in its
3918 own variable so any optimizers that need this information don't have
3919 to include tree.h. Do this here so it gets done when an inlined
3920 function gets output. */
3921
3922 crtl->return_rtx
3923 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3924 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3925
3926 /* If scalar return value was computed in a pseudo-reg, or was a named
3927 return value that got dumped to the stack, copy that to the hard
3928 return register. */
3929 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3930 {
3931 tree decl_result = DECL_RESULT (fndecl);
3932 rtx decl_rtl = DECL_RTL (decl_result);
3933
3934 if (REG_P (decl_rtl)
3935 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3936 : DECL_REGISTER (decl_result))
3937 {
3938 rtx real_decl_rtl;
3939
3940 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3941 fndecl, true);
3942 if (chkp_function_instrumented_p (fndecl))
3943 crtl->return_bnd
3944 = targetm.calls.chkp_function_value_bounds (TREE_TYPE (decl_result),
3945 fndecl, true);
3946 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3947 /* The delay slot scheduler assumes that crtl->return_rtx
3948 holds the hard register containing the return value, not a
3949 temporary pseudo. */
3950 crtl->return_rtx = real_decl_rtl;
3951 }
3952 }
3953 }
3954
3955 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3956 For all seen types, gimplify their sizes. */
3957
3958 static tree
3959 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3960 {
3961 tree t = *tp;
3962
3963 *walk_subtrees = 0;
3964 if (TYPE_P (t))
3965 {
3966 if (POINTER_TYPE_P (t))
3967 *walk_subtrees = 1;
3968 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3969 && !TYPE_SIZES_GIMPLIFIED (t))
3970 {
3971 gimplify_type_sizes (t, (gimple_seq *) data);
3972 *walk_subtrees = 1;
3973 }
3974 }
3975
3976 return NULL;
3977 }
3978
3979 /* Gimplify the parameter list for current_function_decl. This involves
3980 evaluating SAVE_EXPRs of variable sized parameters and generating code
3981 to implement callee-copies reference parameters. Returns a sequence of
3982 statements to add to the beginning of the function. */
3983
3984 gimple_seq
3985 gimplify_parameters (void)
3986 {
3987 struct assign_parm_data_all all;
3988 tree parm;
3989 gimple_seq stmts = NULL;
3990 vec<tree> fnargs;
3991 unsigned i;
3992
3993 assign_parms_initialize_all (&all);
3994 fnargs = assign_parms_augmented_arg_list (&all);
3995
3996 FOR_EACH_VEC_ELT (fnargs, i, parm)
3997 {
3998 struct assign_parm_data_one data;
3999
4000 /* Extract the type of PARM; adjust it according to ABI. */
4001 assign_parm_find_data_types (&all, parm, &data);
4002
4003 /* Early out for errors and void parameters. */
4004 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
4005 continue;
4006
4007 /* Update info on where next arg arrives in registers. */
4008 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
4009 data.passed_type, data.named_arg);
4010
4011 /* ??? Once upon a time variable_size stuffed parameter list
4012 SAVE_EXPRs (amongst others) onto a pending sizes list. This
4013 turned out to be less than manageable in the gimple world.
4014 Now we have to hunt them down ourselves. */
4015 walk_tree_without_duplicates (&data.passed_type,
4016 gimplify_parm_type, &stmts);
4017
4018 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
4019 {
4020 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
4021 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
4022 }
4023
4024 if (data.passed_pointer)
4025 {
4026 tree type = TREE_TYPE (data.passed_type);
4027 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
4028 type, data.named_arg))
4029 {
4030 tree local, t;
4031
4032 /* For constant-sized objects, this is trivial; for
4033 variable-sized objects, we have to play games. */
4034 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
4035 && !(flag_stack_check == GENERIC_STACK_CHECK
4036 && compare_tree_int (DECL_SIZE_UNIT (parm),
4037 STACK_CHECK_MAX_VAR_SIZE) > 0))
4038 {
4039 local = create_tmp_var (type, get_name (parm));
4040 DECL_IGNORED_P (local) = 0;
4041 /* If PARM was addressable, move that flag over
4042 to the local copy, as its address will be taken,
4043 not the PARMs. Keep the parms address taken
4044 as we'll query that flag during gimplification. */
4045 if (TREE_ADDRESSABLE (parm))
4046 TREE_ADDRESSABLE (local) = 1;
4047 else if (TREE_CODE (type) == COMPLEX_TYPE
4048 || TREE_CODE (type) == VECTOR_TYPE)
4049 DECL_GIMPLE_REG_P (local) = 1;
4050 }
4051 else
4052 {
4053 tree ptr_type, addr;
4054
4055 ptr_type = build_pointer_type (type);
4056 addr = create_tmp_reg (ptr_type, get_name (parm));
4057 DECL_IGNORED_P (addr) = 0;
4058 local = build_fold_indirect_ref (addr);
4059
4060 t = build_alloca_call_expr (DECL_SIZE_UNIT (parm),
4061 DECL_ALIGN (parm),
4062 max_int_size_in_bytes (type));
4063 /* The call has been built for a variable-sized object. */
4064 CALL_ALLOCA_FOR_VAR_P (t) = 1;
4065 t = fold_convert (ptr_type, t);
4066 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
4067 gimplify_and_add (t, &stmts);
4068 }
4069
4070 gimplify_assign (local, parm, &stmts);
4071
4072 SET_DECL_VALUE_EXPR (parm, local);
4073 DECL_HAS_VALUE_EXPR_P (parm) = 1;
4074 }
4075 }
4076 }
4077
4078 fnargs.release ();
4079
4080 return stmts;
4081 }
4082 \f
4083 /* Compute the size and offset from the start of the stacked arguments for a
4084 parm passed in mode PASSED_MODE and with type TYPE.
4085
4086 INITIAL_OFFSET_PTR points to the current offset into the stacked
4087 arguments.
4088
4089 The starting offset and size for this parm are returned in
4090 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
4091 nonzero, the offset is that of stack slot, which is returned in
4092 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
4093 padding required from the initial offset ptr to the stack slot.
4094
4095 IN_REGS is nonzero if the argument will be passed in registers. It will
4096 never be set if REG_PARM_STACK_SPACE is not defined.
4097
4098 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
4099 for arguments which are passed in registers.
4100
4101 FNDECL is the function in which the argument was defined.
4102
4103 There are two types of rounding that are done. The first, controlled by
4104 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
4105 argument list to be aligned to the specific boundary (in bits). This
4106 rounding affects the initial and starting offsets, but not the argument
4107 size.
4108
4109 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4110 optionally rounds the size of the parm to PARM_BOUNDARY. The
4111 initial offset is not affected by this rounding, while the size always
4112 is and the starting offset may be. */
4113
4114 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
4115 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
4116 callers pass in the total size of args so far as
4117 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
4118
4119 void
4120 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
4121 int reg_parm_stack_space, int partial,
4122 tree fndecl ATTRIBUTE_UNUSED,
4123 struct args_size *initial_offset_ptr,
4124 struct locate_and_pad_arg_data *locate)
4125 {
4126 tree sizetree;
4127 pad_direction where_pad;
4128 unsigned int boundary, round_boundary;
4129 int part_size_in_regs;
4130
4131 /* If we have found a stack parm before we reach the end of the
4132 area reserved for registers, skip that area. */
4133 if (! in_regs)
4134 {
4135 if (reg_parm_stack_space > 0)
4136 {
4137 if (initial_offset_ptr->var)
4138 {
4139 initial_offset_ptr->var
4140 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4141 ssize_int (reg_parm_stack_space));
4142 initial_offset_ptr->constant = 0;
4143 }
4144 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4145 initial_offset_ptr->constant = reg_parm_stack_space;
4146 }
4147 }
4148
4149 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
4150
4151 sizetree = (type
4152 ? arg_size_in_bytes (type)
4153 : size_int (GET_MODE_SIZE (passed_mode)));
4154 where_pad = targetm.calls.function_arg_padding (passed_mode, type);
4155 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
4156 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
4157 type);
4158 locate->where_pad = where_pad;
4159
4160 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4161 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
4162 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
4163
4164 locate->boundary = boundary;
4165
4166 if (SUPPORTS_STACK_ALIGNMENT)
4167 {
4168 /* stack_alignment_estimated can't change after stack has been
4169 realigned. */
4170 if (crtl->stack_alignment_estimated < boundary)
4171 {
4172 if (!crtl->stack_realign_processed)
4173 crtl->stack_alignment_estimated = boundary;
4174 else
4175 {
4176 /* If stack is realigned and stack alignment value
4177 hasn't been finalized, it is OK not to increase
4178 stack_alignment_estimated. The bigger alignment
4179 requirement is recorded in stack_alignment_needed
4180 below. */
4181 gcc_assert (!crtl->stack_realign_finalized
4182 && crtl->stack_realign_needed);
4183 }
4184 }
4185 }
4186
4187 /* Remember if the outgoing parameter requires extra alignment on the
4188 calling function side. */
4189 if (crtl->stack_alignment_needed < boundary)
4190 crtl->stack_alignment_needed = boundary;
4191 if (crtl->preferred_stack_boundary < boundary)
4192 crtl->preferred_stack_boundary = boundary;
4193
4194 if (ARGS_GROW_DOWNWARD)
4195 {
4196 locate->slot_offset.constant = -initial_offset_ptr->constant;
4197 if (initial_offset_ptr->var)
4198 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4199 initial_offset_ptr->var);
4200
4201 {
4202 tree s2 = sizetree;
4203 if (where_pad != PAD_NONE
4204 && (!tree_fits_uhwi_p (sizetree)
4205 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4206 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4207 SUB_PARM_SIZE (locate->slot_offset, s2);
4208 }
4209
4210 locate->slot_offset.constant += part_size_in_regs;
4211
4212 if (!in_regs || reg_parm_stack_space > 0)
4213 pad_to_arg_alignment (&locate->slot_offset, boundary,
4214 &locate->alignment_pad);
4215
4216 locate->size.constant = (-initial_offset_ptr->constant
4217 - locate->slot_offset.constant);
4218 if (initial_offset_ptr->var)
4219 locate->size.var = size_binop (MINUS_EXPR,
4220 size_binop (MINUS_EXPR,
4221 ssize_int (0),
4222 initial_offset_ptr->var),
4223 locate->slot_offset.var);
4224
4225 /* Pad_below needs the pre-rounded size to know how much to pad
4226 below. */
4227 locate->offset = locate->slot_offset;
4228 if (where_pad == PAD_DOWNWARD)
4229 pad_below (&locate->offset, passed_mode, sizetree);
4230
4231 }
4232 else
4233 {
4234 if (!in_regs || reg_parm_stack_space > 0)
4235 pad_to_arg_alignment (initial_offset_ptr, boundary,
4236 &locate->alignment_pad);
4237 locate->slot_offset = *initial_offset_ptr;
4238
4239 #ifdef PUSH_ROUNDING
4240 if (passed_mode != BLKmode)
4241 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4242 #endif
4243
4244 /* Pad_below needs the pre-rounded size to know how much to pad below
4245 so this must be done before rounding up. */
4246 locate->offset = locate->slot_offset;
4247 if (where_pad == PAD_DOWNWARD)
4248 pad_below (&locate->offset, passed_mode, sizetree);
4249
4250 if (where_pad != PAD_NONE
4251 && (!tree_fits_uhwi_p (sizetree)
4252 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4253 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4254
4255 ADD_PARM_SIZE (locate->size, sizetree);
4256
4257 locate->size.constant -= part_size_in_regs;
4258 }
4259
4260 locate->offset.constant
4261 += targetm.calls.function_arg_offset (passed_mode, type);
4262 }
4263
4264 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4265 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4266
4267 static void
4268 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4269 struct args_size *alignment_pad)
4270 {
4271 tree save_var = NULL_TREE;
4272 HOST_WIDE_INT save_constant = 0;
4273 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4274 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
4275
4276 #ifdef SPARC_STACK_BOUNDARY_HACK
4277 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4278 the real alignment of %sp. However, when it does this, the
4279 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4280 if (SPARC_STACK_BOUNDARY_HACK)
4281 sp_offset = 0;
4282 #endif
4283
4284 if (boundary > PARM_BOUNDARY)
4285 {
4286 save_var = offset_ptr->var;
4287 save_constant = offset_ptr->constant;
4288 }
4289
4290 alignment_pad->var = NULL_TREE;
4291 alignment_pad->constant = 0;
4292
4293 if (boundary > BITS_PER_UNIT)
4294 {
4295 if (offset_ptr->var)
4296 {
4297 tree sp_offset_tree = ssize_int (sp_offset);
4298 tree offset = size_binop (PLUS_EXPR,
4299 ARGS_SIZE_TREE (*offset_ptr),
4300 sp_offset_tree);
4301 tree rounded;
4302 if (ARGS_GROW_DOWNWARD)
4303 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4304 else
4305 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4306
4307 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4308 /* ARGS_SIZE_TREE includes constant term. */
4309 offset_ptr->constant = 0;
4310 if (boundary > PARM_BOUNDARY)
4311 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4312 save_var);
4313 }
4314 else
4315 {
4316 offset_ptr->constant = -sp_offset +
4317 (ARGS_GROW_DOWNWARD
4318 ? FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes)
4319 : CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes));
4320
4321 if (boundary > PARM_BOUNDARY)
4322 alignment_pad->constant = offset_ptr->constant - save_constant;
4323 }
4324 }
4325 }
4326
4327 static void
4328 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4329 {
4330 unsigned int align = PARM_BOUNDARY / BITS_PER_UNIT;
4331 if (passed_mode != BLKmode)
4332 offset_ptr->constant += -GET_MODE_SIZE (passed_mode) & (align - 1);
4333 else
4334 {
4335 if (TREE_CODE (sizetree) != INTEGER_CST
4336 || (TREE_INT_CST_LOW (sizetree) & (align - 1)) != 0)
4337 {
4338 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4339 tree s2 = round_up (sizetree, align);
4340 /* Add it in. */
4341 ADD_PARM_SIZE (*offset_ptr, s2);
4342 SUB_PARM_SIZE (*offset_ptr, sizetree);
4343 }
4344 }
4345 }
4346 \f
4347
4348 /* True if register REGNO was alive at a place where `setjmp' was
4349 called and was set more than once or is an argument. Such regs may
4350 be clobbered by `longjmp'. */
4351
4352 static bool
4353 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4354 {
4355 /* There appear to be cases where some local vars never reach the
4356 backend but have bogus regnos. */
4357 if (regno >= max_reg_num ())
4358 return false;
4359
4360 return ((REG_N_SETS (regno) > 1
4361 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4362 regno))
4363 && REGNO_REG_SET_P (setjmp_crosses, regno));
4364 }
4365
4366 /* Walk the tree of blocks describing the binding levels within a
4367 function and warn about variables the might be killed by setjmp or
4368 vfork. This is done after calling flow_analysis before register
4369 allocation since that will clobber the pseudo-regs to hard
4370 regs. */
4371
4372 static void
4373 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4374 {
4375 tree decl, sub;
4376
4377 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4378 {
4379 if (VAR_P (decl)
4380 && DECL_RTL_SET_P (decl)
4381 && REG_P (DECL_RTL (decl))
4382 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4383 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4384 " %<longjmp%> or %<vfork%>", decl);
4385 }
4386
4387 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4388 setjmp_vars_warning (setjmp_crosses, sub);
4389 }
4390
4391 /* Do the appropriate part of setjmp_vars_warning
4392 but for arguments instead of local variables. */
4393
4394 static void
4395 setjmp_args_warning (bitmap setjmp_crosses)
4396 {
4397 tree decl;
4398 for (decl = DECL_ARGUMENTS (current_function_decl);
4399 decl; decl = DECL_CHAIN (decl))
4400 if (DECL_RTL (decl) != 0
4401 && REG_P (DECL_RTL (decl))
4402 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4403 warning (OPT_Wclobbered,
4404 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4405 decl);
4406 }
4407
4408 /* Generate warning messages for variables live across setjmp. */
4409
4410 void
4411 generate_setjmp_warnings (void)
4412 {
4413 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4414
4415 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4416 || bitmap_empty_p (setjmp_crosses))
4417 return;
4418
4419 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4420 setjmp_args_warning (setjmp_crosses);
4421 }
4422
4423 \f
4424 /* Reverse the order of elements in the fragment chain T of blocks,
4425 and return the new head of the chain (old last element).
4426 In addition to that clear BLOCK_SAME_RANGE flags when needed
4427 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4428 its super fragment origin. */
4429
4430 static tree
4431 block_fragments_nreverse (tree t)
4432 {
4433 tree prev = 0, block, next, prev_super = 0;
4434 tree super = BLOCK_SUPERCONTEXT (t);
4435 if (BLOCK_FRAGMENT_ORIGIN (super))
4436 super = BLOCK_FRAGMENT_ORIGIN (super);
4437 for (block = t; block; block = next)
4438 {
4439 next = BLOCK_FRAGMENT_CHAIN (block);
4440 BLOCK_FRAGMENT_CHAIN (block) = prev;
4441 if ((prev && !BLOCK_SAME_RANGE (prev))
4442 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4443 != prev_super))
4444 BLOCK_SAME_RANGE (block) = 0;
4445 prev_super = BLOCK_SUPERCONTEXT (block);
4446 BLOCK_SUPERCONTEXT (block) = super;
4447 prev = block;
4448 }
4449 t = BLOCK_FRAGMENT_ORIGIN (t);
4450 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4451 != prev_super)
4452 BLOCK_SAME_RANGE (t) = 0;
4453 BLOCK_SUPERCONTEXT (t) = super;
4454 return prev;
4455 }
4456
4457 /* Reverse the order of elements in the chain T of blocks,
4458 and return the new head of the chain (old last element).
4459 Also do the same on subblocks and reverse the order of elements
4460 in BLOCK_FRAGMENT_CHAIN as well. */
4461
4462 static tree
4463 blocks_nreverse_all (tree t)
4464 {
4465 tree prev = 0, block, next;
4466 for (block = t; block; block = next)
4467 {
4468 next = BLOCK_CHAIN (block);
4469 BLOCK_CHAIN (block) = prev;
4470 if (BLOCK_FRAGMENT_CHAIN (block)
4471 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4472 {
4473 BLOCK_FRAGMENT_CHAIN (block)
4474 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4475 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4476 BLOCK_SAME_RANGE (block) = 0;
4477 }
4478 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4479 prev = block;
4480 }
4481 return prev;
4482 }
4483
4484
4485 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4486 and create duplicate blocks. */
4487 /* ??? Need an option to either create block fragments or to create
4488 abstract origin duplicates of a source block. It really depends
4489 on what optimization has been performed. */
4490
4491 void
4492 reorder_blocks (void)
4493 {
4494 tree block = DECL_INITIAL (current_function_decl);
4495
4496 if (block == NULL_TREE)
4497 return;
4498
4499 auto_vec<tree, 10> block_stack;
4500
4501 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4502 clear_block_marks (block);
4503
4504 /* Prune the old trees away, so that they don't get in the way. */
4505 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4506 BLOCK_CHAIN (block) = NULL_TREE;
4507
4508 /* Recreate the block tree from the note nesting. */
4509 reorder_blocks_1 (get_insns (), block, &block_stack);
4510 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4511 }
4512
4513 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4514
4515 void
4516 clear_block_marks (tree block)
4517 {
4518 while (block)
4519 {
4520 TREE_ASM_WRITTEN (block) = 0;
4521 clear_block_marks (BLOCK_SUBBLOCKS (block));
4522 block = BLOCK_CHAIN (block);
4523 }
4524 }
4525
4526 static void
4527 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4528 vec<tree> *p_block_stack)
4529 {
4530 rtx_insn *insn;
4531 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4532
4533 for (insn = insns; insn; insn = NEXT_INSN (insn))
4534 {
4535 if (NOTE_P (insn))
4536 {
4537 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4538 {
4539 tree block = NOTE_BLOCK (insn);
4540 tree origin;
4541
4542 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4543 origin = block;
4544
4545 if (prev_end)
4546 BLOCK_SAME_RANGE (prev_end) = 0;
4547 prev_end = NULL_TREE;
4548
4549 /* If we have seen this block before, that means it now
4550 spans multiple address regions. Create a new fragment. */
4551 if (TREE_ASM_WRITTEN (block))
4552 {
4553 tree new_block = copy_node (block);
4554
4555 BLOCK_SAME_RANGE (new_block) = 0;
4556 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4557 BLOCK_FRAGMENT_CHAIN (new_block)
4558 = BLOCK_FRAGMENT_CHAIN (origin);
4559 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4560
4561 NOTE_BLOCK (insn) = new_block;
4562 block = new_block;
4563 }
4564
4565 if (prev_beg == current_block && prev_beg)
4566 BLOCK_SAME_RANGE (block) = 1;
4567
4568 prev_beg = origin;
4569
4570 BLOCK_SUBBLOCKS (block) = 0;
4571 TREE_ASM_WRITTEN (block) = 1;
4572 /* When there's only one block for the entire function,
4573 current_block == block and we mustn't do this, it
4574 will cause infinite recursion. */
4575 if (block != current_block)
4576 {
4577 tree super;
4578 if (block != origin)
4579 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4580 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4581 (origin))
4582 == current_block);
4583 if (p_block_stack->is_empty ())
4584 super = current_block;
4585 else
4586 {
4587 super = p_block_stack->last ();
4588 gcc_assert (super == current_block
4589 || BLOCK_FRAGMENT_ORIGIN (super)
4590 == current_block);
4591 }
4592 BLOCK_SUPERCONTEXT (block) = super;
4593 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4594 BLOCK_SUBBLOCKS (current_block) = block;
4595 current_block = origin;
4596 }
4597 p_block_stack->safe_push (block);
4598 }
4599 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4600 {
4601 NOTE_BLOCK (insn) = p_block_stack->pop ();
4602 current_block = BLOCK_SUPERCONTEXT (current_block);
4603 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4604 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4605 prev_beg = NULL_TREE;
4606 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4607 ? NOTE_BLOCK (insn) : NULL_TREE;
4608 }
4609 }
4610 else
4611 {
4612 prev_beg = NULL_TREE;
4613 if (prev_end)
4614 BLOCK_SAME_RANGE (prev_end) = 0;
4615 prev_end = NULL_TREE;
4616 }
4617 }
4618 }
4619
4620 /* Reverse the order of elements in the chain T of blocks,
4621 and return the new head of the chain (old last element). */
4622
4623 tree
4624 blocks_nreverse (tree t)
4625 {
4626 tree prev = 0, block, next;
4627 for (block = t; block; block = next)
4628 {
4629 next = BLOCK_CHAIN (block);
4630 BLOCK_CHAIN (block) = prev;
4631 prev = block;
4632 }
4633 return prev;
4634 }
4635
4636 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4637 by modifying the last node in chain 1 to point to chain 2. */
4638
4639 tree
4640 block_chainon (tree op1, tree op2)
4641 {
4642 tree t1;
4643
4644 if (!op1)
4645 return op2;
4646 if (!op2)
4647 return op1;
4648
4649 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4650 continue;
4651 BLOCK_CHAIN (t1) = op2;
4652
4653 #ifdef ENABLE_TREE_CHECKING
4654 {
4655 tree t2;
4656 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4657 gcc_assert (t2 != t1);
4658 }
4659 #endif
4660
4661 return op1;
4662 }
4663
4664 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4665 non-NULL, list them all into VECTOR, in a depth-first preorder
4666 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4667 blocks. */
4668
4669 static int
4670 all_blocks (tree block, tree *vector)
4671 {
4672 int n_blocks = 0;
4673
4674 while (block)
4675 {
4676 TREE_ASM_WRITTEN (block) = 0;
4677
4678 /* Record this block. */
4679 if (vector)
4680 vector[n_blocks] = block;
4681
4682 ++n_blocks;
4683
4684 /* Record the subblocks, and their subblocks... */
4685 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4686 vector ? vector + n_blocks : 0);
4687 block = BLOCK_CHAIN (block);
4688 }
4689
4690 return n_blocks;
4691 }
4692
4693 /* Return a vector containing all the blocks rooted at BLOCK. The
4694 number of elements in the vector is stored in N_BLOCKS_P. The
4695 vector is dynamically allocated; it is the caller's responsibility
4696 to call `free' on the pointer returned. */
4697
4698 static tree *
4699 get_block_vector (tree block, int *n_blocks_p)
4700 {
4701 tree *block_vector;
4702
4703 *n_blocks_p = all_blocks (block, NULL);
4704 block_vector = XNEWVEC (tree, *n_blocks_p);
4705 all_blocks (block, block_vector);
4706
4707 return block_vector;
4708 }
4709
4710 static GTY(()) int next_block_index = 2;
4711
4712 /* Set BLOCK_NUMBER for all the blocks in FN. */
4713
4714 void
4715 number_blocks (tree fn)
4716 {
4717 int i;
4718 int n_blocks;
4719 tree *block_vector;
4720
4721 /* For XCOFF debugging output, we start numbering the blocks
4722 from 1 within each function, rather than keeping a running
4723 count. */
4724 #if defined (XCOFF_DEBUGGING_INFO)
4725 if (write_symbols == XCOFF_DEBUG)
4726 next_block_index = 1;
4727 #endif
4728
4729 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4730
4731 /* The top-level BLOCK isn't numbered at all. */
4732 for (i = 1; i < n_blocks; ++i)
4733 /* We number the blocks from two. */
4734 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4735
4736 free (block_vector);
4737
4738 return;
4739 }
4740
4741 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4742
4743 DEBUG_FUNCTION tree
4744 debug_find_var_in_block_tree (tree var, tree block)
4745 {
4746 tree t;
4747
4748 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4749 if (t == var)
4750 return block;
4751
4752 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4753 {
4754 tree ret = debug_find_var_in_block_tree (var, t);
4755 if (ret)
4756 return ret;
4757 }
4758
4759 return NULL_TREE;
4760 }
4761 \f
4762 /* Keep track of whether we're in a dummy function context. If we are,
4763 we don't want to invoke the set_current_function hook, because we'll
4764 get into trouble if the hook calls target_reinit () recursively or
4765 when the initial initialization is not yet complete. */
4766
4767 static bool in_dummy_function;
4768
4769 /* Invoke the target hook when setting cfun. Update the optimization options
4770 if the function uses different options than the default. */
4771
4772 static void
4773 invoke_set_current_function_hook (tree fndecl)
4774 {
4775 if (!in_dummy_function)
4776 {
4777 tree opts = ((fndecl)
4778 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4779 : optimization_default_node);
4780
4781 if (!opts)
4782 opts = optimization_default_node;
4783
4784 /* Change optimization options if needed. */
4785 if (optimization_current_node != opts)
4786 {
4787 optimization_current_node = opts;
4788 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4789 }
4790
4791 targetm.set_current_function (fndecl);
4792 this_fn_optabs = this_target_optabs;
4793
4794 if (opts != optimization_default_node)
4795 {
4796 init_tree_optimization_optabs (opts);
4797 if (TREE_OPTIMIZATION_OPTABS (opts))
4798 this_fn_optabs = (struct target_optabs *)
4799 TREE_OPTIMIZATION_OPTABS (opts);
4800 }
4801 }
4802 }
4803
4804 /* cfun should never be set directly; use this function. */
4805
4806 void
4807 set_cfun (struct function *new_cfun, bool force)
4808 {
4809 if (cfun != new_cfun || force)
4810 {
4811 cfun = new_cfun;
4812 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4813 redirect_edge_var_map_empty ();
4814 }
4815 }
4816
4817 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4818
4819 static vec<function *> cfun_stack;
4820
4821 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4822 current_function_decl accordingly. */
4823
4824 void
4825 push_cfun (struct function *new_cfun)
4826 {
4827 gcc_assert ((!cfun && !current_function_decl)
4828 || (cfun && current_function_decl == cfun->decl));
4829 cfun_stack.safe_push (cfun);
4830 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4831 set_cfun (new_cfun);
4832 }
4833
4834 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4835
4836 void
4837 pop_cfun (void)
4838 {
4839 struct function *new_cfun = cfun_stack.pop ();
4840 /* When in_dummy_function, we do have a cfun but current_function_decl is
4841 NULL. We also allow pushing NULL cfun and subsequently changing
4842 current_function_decl to something else and have both restored by
4843 pop_cfun. */
4844 gcc_checking_assert (in_dummy_function
4845 || !cfun
4846 || current_function_decl == cfun->decl);
4847 set_cfun (new_cfun);
4848 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4849 }
4850
4851 /* Return value of funcdef and increase it. */
4852 int
4853 get_next_funcdef_no (void)
4854 {
4855 return funcdef_no++;
4856 }
4857
4858 /* Return value of funcdef. */
4859 int
4860 get_last_funcdef_no (void)
4861 {
4862 return funcdef_no;
4863 }
4864
4865 /* Allocate a function structure for FNDECL and set its contents
4866 to the defaults. Set cfun to the newly-allocated object.
4867 Some of the helper functions invoked during initialization assume
4868 that cfun has already been set. Therefore, assign the new object
4869 directly into cfun and invoke the back end hook explicitly at the
4870 very end, rather than initializing a temporary and calling set_cfun
4871 on it.
4872
4873 ABSTRACT_P is true if this is a function that will never be seen by
4874 the middle-end. Such functions are front-end concepts (like C++
4875 function templates) that do not correspond directly to functions
4876 placed in object files. */
4877
4878 void
4879 allocate_struct_function (tree fndecl, bool abstract_p)
4880 {
4881 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4882
4883 cfun = ggc_cleared_alloc<function> ();
4884
4885 init_eh_for_function ();
4886
4887 if (init_machine_status)
4888 cfun->machine = (*init_machine_status) ();
4889
4890 #ifdef OVERRIDE_ABI_FORMAT
4891 OVERRIDE_ABI_FORMAT (fndecl);
4892 #endif
4893
4894 if (fndecl != NULL_TREE)
4895 {
4896 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4897 cfun->decl = fndecl;
4898 current_function_funcdef_no = get_next_funcdef_no ();
4899 }
4900
4901 invoke_set_current_function_hook (fndecl);
4902
4903 if (fndecl != NULL_TREE)
4904 {
4905 tree result = DECL_RESULT (fndecl);
4906
4907 if (!abstract_p)
4908 {
4909 /* Now that we have activated any function-specific attributes
4910 that might affect layout, particularly vector modes, relayout
4911 each of the parameters and the result. */
4912 relayout_decl (result);
4913 for (tree parm = DECL_ARGUMENTS (fndecl); parm;
4914 parm = DECL_CHAIN (parm))
4915 relayout_decl (parm);
4916
4917 /* Similarly relayout the function decl. */
4918 targetm.target_option.relayout_function (fndecl);
4919 }
4920
4921 if (!abstract_p && aggregate_value_p (result, fndecl))
4922 {
4923 #ifdef PCC_STATIC_STRUCT_RETURN
4924 cfun->returns_pcc_struct = 1;
4925 #endif
4926 cfun->returns_struct = 1;
4927 }
4928
4929 cfun->stdarg = stdarg_p (fntype);
4930
4931 /* Assume all registers in stdarg functions need to be saved. */
4932 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4933 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4934
4935 /* ??? This could be set on a per-function basis by the front-end
4936 but is this worth the hassle? */
4937 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4938 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4939
4940 if (!profile_flag && !flag_instrument_function_entry_exit)
4941 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4942 }
4943
4944 /* Don't enable begin stmt markers if var-tracking at assignments is
4945 disabled. The markers make little sense without the variable
4946 binding annotations among them. */
4947 cfun->debug_nonbind_markers = lang_hooks.emits_begin_stmt
4948 && MAY_HAVE_DEBUG_MARKER_STMTS;
4949 }
4950
4951 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4952 instead of just setting it. */
4953
4954 void
4955 push_struct_function (tree fndecl)
4956 {
4957 /* When in_dummy_function we might be in the middle of a pop_cfun and
4958 current_function_decl and cfun may not match. */
4959 gcc_assert (in_dummy_function
4960 || (!cfun && !current_function_decl)
4961 || (cfun && current_function_decl == cfun->decl));
4962 cfun_stack.safe_push (cfun);
4963 current_function_decl = fndecl;
4964 allocate_struct_function (fndecl, false);
4965 }
4966
4967 /* Reset crtl and other non-struct-function variables to defaults as
4968 appropriate for emitting rtl at the start of a function. */
4969
4970 static void
4971 prepare_function_start (void)
4972 {
4973 gcc_assert (!get_last_insn ());
4974 init_temp_slots ();
4975 init_emit ();
4976 init_varasm_status ();
4977 init_expr ();
4978 default_rtl_profile ();
4979
4980 if (flag_stack_usage_info)
4981 {
4982 cfun->su = ggc_cleared_alloc<stack_usage> ();
4983 cfun->su->static_stack_size = -1;
4984 }
4985
4986 cse_not_expected = ! optimize;
4987
4988 /* Caller save not needed yet. */
4989 caller_save_needed = 0;
4990
4991 /* We haven't done register allocation yet. */
4992 reg_renumber = 0;
4993
4994 /* Indicate that we have not instantiated virtual registers yet. */
4995 virtuals_instantiated = 0;
4996
4997 /* Indicate that we want CONCATs now. */
4998 generating_concat_p = 1;
4999
5000 /* Indicate we have no need of a frame pointer yet. */
5001 frame_pointer_needed = 0;
5002 }
5003
5004 void
5005 push_dummy_function (bool with_decl)
5006 {
5007 tree fn_decl, fn_type, fn_result_decl;
5008
5009 gcc_assert (!in_dummy_function);
5010 in_dummy_function = true;
5011
5012 if (with_decl)
5013 {
5014 fn_type = build_function_type_list (void_type_node, NULL_TREE);
5015 fn_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
5016 fn_type);
5017 fn_result_decl = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
5018 NULL_TREE, void_type_node);
5019 DECL_RESULT (fn_decl) = fn_result_decl;
5020 }
5021 else
5022 fn_decl = NULL_TREE;
5023
5024 push_struct_function (fn_decl);
5025 }
5026
5027 /* Initialize the rtl expansion mechanism so that we can do simple things
5028 like generate sequences. This is used to provide a context during global
5029 initialization of some passes. You must call expand_dummy_function_end
5030 to exit this context. */
5031
5032 void
5033 init_dummy_function_start (void)
5034 {
5035 push_dummy_function (false);
5036 prepare_function_start ();
5037 }
5038
5039 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5040 and initialize static variables for generating RTL for the statements
5041 of the function. */
5042
5043 void
5044 init_function_start (tree subr)
5045 {
5046 /* Initialize backend, if needed. */
5047 initialize_rtl ();
5048
5049 prepare_function_start ();
5050 decide_function_section (subr);
5051
5052 /* Warn if this value is an aggregate type,
5053 regardless of which calling convention we are using for it. */
5054 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5055 warning (OPT_Waggregate_return, "function returns an aggregate");
5056 }
5057
5058 /* Expand code to verify the stack_protect_guard. This is invoked at
5059 the end of a function to be protected. */
5060
5061 void
5062 stack_protect_epilogue (void)
5063 {
5064 tree guard_decl = targetm.stack_protect_guard ();
5065 rtx_code_label *label = gen_label_rtx ();
5066 rtx x, y;
5067 rtx_insn *seq;
5068
5069 x = expand_normal (crtl->stack_protect_guard);
5070 if (guard_decl)
5071 y = expand_normal (guard_decl);
5072 else
5073 y = const0_rtx;
5074
5075 /* Allow the target to compare Y with X without leaking either into
5076 a register. */
5077 if (targetm.have_stack_protect_test ()
5078 && ((seq = targetm.gen_stack_protect_test (x, y, label)) != NULL_RTX))
5079 emit_insn (seq);
5080 else
5081 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
5082
5083 /* The noreturn predictor has been moved to the tree level. The rtl-level
5084 predictors estimate this branch about 20%, which isn't enough to get
5085 things moved out of line. Since this is the only extant case of adding
5086 a noreturn function at the rtl level, it doesn't seem worth doing ought
5087 except adding the prediction by hand. */
5088 rtx_insn *tmp = get_last_insn ();
5089 if (JUMP_P (tmp))
5090 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
5091
5092 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
5093 free_temp_slots ();
5094 emit_label (label);
5095 }
5096 \f
5097 /* Start the RTL for a new function, and set variables used for
5098 emitting RTL.
5099 SUBR is the FUNCTION_DECL node.
5100 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5101 the function's parameters, which must be run at any return statement. */
5102
5103 void
5104 expand_function_start (tree subr)
5105 {
5106 /* Make sure volatile mem refs aren't considered
5107 valid operands of arithmetic insns. */
5108 init_recog_no_volatile ();
5109
5110 crtl->profile
5111 = (profile_flag
5112 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5113
5114 crtl->limit_stack
5115 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
5116
5117 /* Make the label for return statements to jump to. Do not special
5118 case machines with special return instructions -- they will be
5119 handled later during jump, ifcvt, or epilogue creation. */
5120 return_label = gen_label_rtx ();
5121
5122 /* Initialize rtx used to return the value. */
5123 /* Do this before assign_parms so that we copy the struct value address
5124 before any library calls that assign parms might generate. */
5125
5126 /* Decide whether to return the value in memory or in a register. */
5127 tree res = DECL_RESULT (subr);
5128 if (aggregate_value_p (res, subr))
5129 {
5130 /* Returning something that won't go in a register. */
5131 rtx value_address = 0;
5132
5133 #ifdef PCC_STATIC_STRUCT_RETURN
5134 if (cfun->returns_pcc_struct)
5135 {
5136 int size = int_size_in_bytes (TREE_TYPE (res));
5137 value_address = assemble_static_space (size);
5138 }
5139 else
5140 #endif
5141 {
5142 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
5143 /* Expect to be passed the address of a place to store the value.
5144 If it is passed as an argument, assign_parms will take care of
5145 it. */
5146 if (sv)
5147 {
5148 value_address = gen_reg_rtx (Pmode);
5149 emit_move_insn (value_address, sv);
5150 }
5151 }
5152 if (value_address)
5153 {
5154 rtx x = value_address;
5155 if (!DECL_BY_REFERENCE (res))
5156 {
5157 x = gen_rtx_MEM (DECL_MODE (res), x);
5158 set_mem_attributes (x, res, 1);
5159 }
5160 set_parm_rtl (res, x);
5161 }
5162 }
5163 else if (DECL_MODE (res) == VOIDmode)
5164 /* If return mode is void, this decl rtl should not be used. */
5165 set_parm_rtl (res, NULL_RTX);
5166 else
5167 {
5168 /* Compute the return values into a pseudo reg, which we will copy
5169 into the true return register after the cleanups are done. */
5170 tree return_type = TREE_TYPE (res);
5171
5172 /* If we may coalesce this result, make sure it has the expected mode
5173 in case it was promoted. But we need not bother about BLKmode. */
5174 machine_mode promoted_mode
5175 = flag_tree_coalesce_vars && is_gimple_reg (res)
5176 ? promote_ssa_mode (ssa_default_def (cfun, res), NULL)
5177 : BLKmode;
5178
5179 if (promoted_mode != BLKmode)
5180 set_parm_rtl (res, gen_reg_rtx (promoted_mode));
5181 else if (TYPE_MODE (return_type) != BLKmode
5182 && targetm.calls.return_in_msb (return_type))
5183 /* expand_function_end will insert the appropriate padding in
5184 this case. Use the return value's natural (unpadded) mode
5185 within the function proper. */
5186 set_parm_rtl (res, gen_reg_rtx (TYPE_MODE (return_type)));
5187 else
5188 {
5189 /* In order to figure out what mode to use for the pseudo, we
5190 figure out what the mode of the eventual return register will
5191 actually be, and use that. */
5192 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
5193
5194 /* Structures that are returned in registers are not
5195 aggregate_value_p, so we may see a PARALLEL or a REG. */
5196 if (REG_P (hard_reg))
5197 set_parm_rtl (res, gen_reg_rtx (GET_MODE (hard_reg)));
5198 else
5199 {
5200 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5201 set_parm_rtl (res, gen_group_rtx (hard_reg));
5202 }
5203 }
5204
5205 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5206 result to the real return register(s). */
5207 DECL_REGISTER (res) = 1;
5208
5209 if (chkp_function_instrumented_p (current_function_decl))
5210 {
5211 tree return_type = TREE_TYPE (res);
5212 rtx bounds = targetm.calls.chkp_function_value_bounds (return_type,
5213 subr, 1);
5214 SET_DECL_BOUNDS_RTL (res, bounds);
5215 }
5216 }
5217
5218 /* Initialize rtx for parameters and local variables.
5219 In some cases this requires emitting insns. */
5220 assign_parms (subr);
5221
5222 /* If function gets a static chain arg, store it. */
5223 if (cfun->static_chain_decl)
5224 {
5225 tree parm = cfun->static_chain_decl;
5226 rtx local, chain;
5227 rtx_insn *insn;
5228 int unsignedp;
5229
5230 local = gen_reg_rtx (promote_decl_mode (parm, &unsignedp));
5231 chain = targetm.calls.static_chain (current_function_decl, true);
5232
5233 set_decl_incoming_rtl (parm, chain, false);
5234 set_parm_rtl (parm, local);
5235 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5236
5237 if (GET_MODE (local) != GET_MODE (chain))
5238 {
5239 convert_move (local, chain, unsignedp);
5240 insn = get_last_insn ();
5241 }
5242 else
5243 insn = emit_move_insn (local, chain);
5244
5245 /* Mark the register as eliminable, similar to parameters. */
5246 if (MEM_P (chain)
5247 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
5248 set_dst_reg_note (insn, REG_EQUIV, chain, local);
5249
5250 /* If we aren't optimizing, save the static chain onto the stack. */
5251 if (!optimize)
5252 {
5253 tree saved_static_chain_decl
5254 = build_decl (DECL_SOURCE_LOCATION (parm), VAR_DECL,
5255 DECL_NAME (parm), TREE_TYPE (parm));
5256 rtx saved_static_chain_rtx
5257 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5258 SET_DECL_RTL (saved_static_chain_decl, saved_static_chain_rtx);
5259 emit_move_insn (saved_static_chain_rtx, chain);
5260 SET_DECL_VALUE_EXPR (parm, saved_static_chain_decl);
5261 DECL_HAS_VALUE_EXPR_P (parm) = 1;
5262 }
5263 }
5264
5265 /* The following was moved from init_function_start.
5266 The move was supposed to make sdb output more accurate. */
5267 /* Indicate the beginning of the function body,
5268 as opposed to parm setup. */
5269 emit_note (NOTE_INSN_FUNCTION_BEG);
5270
5271 gcc_assert (NOTE_P (get_last_insn ()));
5272
5273 parm_birth_insn = get_last_insn ();
5274
5275 /* If the function receives a non-local goto, then store the
5276 bits we need to restore the frame pointer. */
5277 if (cfun->nonlocal_goto_save_area)
5278 {
5279 tree t_save;
5280 rtx r_save;
5281
5282 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5283 gcc_assert (DECL_RTL_SET_P (var));
5284
5285 t_save = build4 (ARRAY_REF,
5286 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
5287 cfun->nonlocal_goto_save_area,
5288 integer_zero_node, NULL_TREE, NULL_TREE);
5289 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
5290 gcc_assert (GET_MODE (r_save) == Pmode);
5291
5292 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
5293 update_nonlocal_goto_save_area ();
5294 }
5295
5296 if (crtl->profile)
5297 {
5298 #ifdef PROFILE_HOOK
5299 PROFILE_HOOK (current_function_funcdef_no);
5300 #endif
5301 }
5302
5303 /* If we are doing generic stack checking, the probe should go here. */
5304 if (flag_stack_check == GENERIC_STACK_CHECK)
5305 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
5306 }
5307 \f
5308 void
5309 pop_dummy_function (void)
5310 {
5311 pop_cfun ();
5312 in_dummy_function = false;
5313 }
5314
5315 /* Undo the effects of init_dummy_function_start. */
5316 void
5317 expand_dummy_function_end (void)
5318 {
5319 gcc_assert (in_dummy_function);
5320
5321 /* End any sequences that failed to be closed due to syntax errors. */
5322 while (in_sequence_p ())
5323 end_sequence ();
5324
5325 /* Outside function body, can't compute type's actual size
5326 until next function's body starts. */
5327
5328 free_after_parsing (cfun);
5329 free_after_compilation (cfun);
5330 pop_dummy_function ();
5331 }
5332
5333 /* Helper for diddle_return_value. */
5334
5335 void
5336 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5337 {
5338 if (! outgoing)
5339 return;
5340
5341 if (REG_P (outgoing))
5342 (*doit) (outgoing, arg);
5343 else if (GET_CODE (outgoing) == PARALLEL)
5344 {
5345 int i;
5346
5347 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5348 {
5349 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5350
5351 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5352 (*doit) (x, arg);
5353 }
5354 }
5355 }
5356
5357 /* Call DOIT for each hard register used as a return value from
5358 the current function. */
5359
5360 void
5361 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5362 {
5363 diddle_return_value_1 (doit, arg, crtl->return_bnd);
5364 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5365 }
5366
5367 static void
5368 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5369 {
5370 emit_clobber (reg);
5371 }
5372
5373 void
5374 clobber_return_register (void)
5375 {
5376 diddle_return_value (do_clobber_return_reg, NULL);
5377
5378 /* In case we do use pseudo to return value, clobber it too. */
5379 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5380 {
5381 tree decl_result = DECL_RESULT (current_function_decl);
5382 rtx decl_rtl = DECL_RTL (decl_result);
5383 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
5384 {
5385 do_clobber_return_reg (decl_rtl, NULL);
5386 }
5387 }
5388 }
5389
5390 static void
5391 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5392 {
5393 emit_use (reg);
5394 }
5395
5396 static void
5397 use_return_register (void)
5398 {
5399 diddle_return_value (do_use_return_reg, NULL);
5400 }
5401
5402 /* Set the location of the insn chain starting at INSN to LOC. */
5403
5404 static void
5405 set_insn_locations (rtx_insn *insn, int loc)
5406 {
5407 while (insn != NULL)
5408 {
5409 if (INSN_P (insn))
5410 INSN_LOCATION (insn) = loc;
5411 insn = NEXT_INSN (insn);
5412 }
5413 }
5414
5415 /* Generate RTL for the end of the current function. */
5416
5417 void
5418 expand_function_end (void)
5419 {
5420 /* If arg_pointer_save_area was referenced only from a nested
5421 function, we will not have initialized it yet. Do that now. */
5422 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
5423 get_arg_pointer_save_area ();
5424
5425 /* If we are doing generic stack checking and this function makes calls,
5426 do a stack probe at the start of the function to ensure we have enough
5427 space for another stack frame. */
5428 if (flag_stack_check == GENERIC_STACK_CHECK)
5429 {
5430 rtx_insn *insn, *seq;
5431
5432 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5433 if (CALL_P (insn))
5434 {
5435 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
5436 start_sequence ();
5437 if (STACK_CHECK_MOVING_SP)
5438 anti_adjust_stack_and_probe (max_frame_size, true);
5439 else
5440 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
5441 seq = get_insns ();
5442 end_sequence ();
5443 set_insn_locations (seq, prologue_location);
5444 emit_insn_before (seq, stack_check_probe_note);
5445 break;
5446 }
5447 }
5448
5449 /* End any sequences that failed to be closed due to syntax errors. */
5450 while (in_sequence_p ())
5451 end_sequence ();
5452
5453 clear_pending_stack_adjust ();
5454 do_pending_stack_adjust ();
5455
5456 /* Output a linenumber for the end of the function.
5457 SDB depended on this. */
5458 set_curr_insn_location (input_location);
5459
5460 /* Before the return label (if any), clobber the return
5461 registers so that they are not propagated live to the rest of
5462 the function. This can only happen with functions that drop
5463 through; if there had been a return statement, there would
5464 have either been a return rtx, or a jump to the return label.
5465
5466 We delay actual code generation after the current_function_value_rtx
5467 is computed. */
5468 rtx_insn *clobber_after = get_last_insn ();
5469
5470 /* Output the label for the actual return from the function. */
5471 emit_label (return_label);
5472
5473 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
5474 {
5475 /* Let except.c know where it should emit the call to unregister
5476 the function context for sjlj exceptions. */
5477 if (flag_exceptions)
5478 sjlj_emit_function_exit_after (get_last_insn ());
5479 }
5480 else
5481 {
5482 /* We want to ensure that instructions that may trap are not
5483 moved into the epilogue by scheduling, because we don't
5484 always emit unwind information for the epilogue. */
5485 if (cfun->can_throw_non_call_exceptions)
5486 emit_insn (gen_blockage ());
5487 }
5488
5489 /* If this is an implementation of throw, do what's necessary to
5490 communicate between __builtin_eh_return and the epilogue. */
5491 expand_eh_return ();
5492
5493 /* If scalar return value was computed in a pseudo-reg, or was a named
5494 return value that got dumped to the stack, copy that to the hard
5495 return register. */
5496 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5497 {
5498 tree decl_result = DECL_RESULT (current_function_decl);
5499 rtx decl_rtl = DECL_RTL (decl_result);
5500
5501 if (REG_P (decl_rtl)
5502 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5503 : DECL_REGISTER (decl_result))
5504 {
5505 rtx real_decl_rtl = crtl->return_rtx;
5506 complex_mode cmode;
5507
5508 /* This should be set in assign_parms. */
5509 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5510
5511 /* If this is a BLKmode structure being returned in registers,
5512 then use the mode computed in expand_return. Note that if
5513 decl_rtl is memory, then its mode may have been changed,
5514 but that crtl->return_rtx has not. */
5515 if (GET_MODE (real_decl_rtl) == BLKmode)
5516 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5517
5518 /* If a non-BLKmode return value should be padded at the least
5519 significant end of the register, shift it left by the appropriate
5520 amount. BLKmode results are handled using the group load/store
5521 machinery. */
5522 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5523 && REG_P (real_decl_rtl)
5524 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5525 {
5526 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5527 REGNO (real_decl_rtl)),
5528 decl_rtl);
5529 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5530 }
5531 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5532 {
5533 /* If expand_function_start has created a PARALLEL for decl_rtl,
5534 move the result to the real return registers. Otherwise, do
5535 a group load from decl_rtl for a named return. */
5536 if (GET_CODE (decl_rtl) == PARALLEL)
5537 emit_group_move (real_decl_rtl, decl_rtl);
5538 else
5539 emit_group_load (real_decl_rtl, decl_rtl,
5540 TREE_TYPE (decl_result),
5541 int_size_in_bytes (TREE_TYPE (decl_result)));
5542 }
5543 /* In the case of complex integer modes smaller than a word, we'll
5544 need to generate some non-trivial bitfield insertions. Do that
5545 on a pseudo and not the hard register. */
5546 else if (GET_CODE (decl_rtl) == CONCAT
5547 && is_complex_int_mode (GET_MODE (decl_rtl), &cmode)
5548 && GET_MODE_BITSIZE (cmode) <= BITS_PER_WORD)
5549 {
5550 int old_generating_concat_p;
5551 rtx tmp;
5552
5553 old_generating_concat_p = generating_concat_p;
5554 generating_concat_p = 0;
5555 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5556 generating_concat_p = old_generating_concat_p;
5557
5558 emit_move_insn (tmp, decl_rtl);
5559 emit_move_insn (real_decl_rtl, tmp);
5560 }
5561 /* If a named return value dumped decl_return to memory, then
5562 we may need to re-do the PROMOTE_MODE signed/unsigned
5563 extension. */
5564 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5565 {
5566 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5567 promote_function_mode (TREE_TYPE (decl_result),
5568 GET_MODE (decl_rtl), &unsignedp,
5569 TREE_TYPE (current_function_decl), 1);
5570
5571 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5572 }
5573 else
5574 emit_move_insn (real_decl_rtl, decl_rtl);
5575 }
5576 }
5577
5578 /* If returning a structure, arrange to return the address of the value
5579 in a place where debuggers expect to find it.
5580
5581 If returning a structure PCC style,
5582 the caller also depends on this value.
5583 And cfun->returns_pcc_struct is not necessarily set. */
5584 if ((cfun->returns_struct || cfun->returns_pcc_struct)
5585 && !targetm.calls.omit_struct_return_reg)
5586 {
5587 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5588 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5589 rtx outgoing;
5590
5591 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5592 type = TREE_TYPE (type);
5593 else
5594 value_address = XEXP (value_address, 0);
5595
5596 outgoing = targetm.calls.function_value (build_pointer_type (type),
5597 current_function_decl, true);
5598
5599 /* Mark this as a function return value so integrate will delete the
5600 assignment and USE below when inlining this function. */
5601 REG_FUNCTION_VALUE_P (outgoing) = 1;
5602
5603 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5604 scalar_int_mode mode = as_a <scalar_int_mode> (GET_MODE (outgoing));
5605 value_address = convert_memory_address (mode, value_address);
5606
5607 emit_move_insn (outgoing, value_address);
5608
5609 /* Show return register used to hold result (in this case the address
5610 of the result. */
5611 crtl->return_rtx = outgoing;
5612 }
5613
5614 /* Emit the actual code to clobber return register. Don't emit
5615 it if clobber_after is a barrier, then the previous basic block
5616 certainly doesn't fall thru into the exit block. */
5617 if (!BARRIER_P (clobber_after))
5618 {
5619 start_sequence ();
5620 clobber_return_register ();
5621 rtx_insn *seq = get_insns ();
5622 end_sequence ();
5623
5624 emit_insn_after (seq, clobber_after);
5625 }
5626
5627 /* Output the label for the naked return from the function. */
5628 if (naked_return_label)
5629 emit_label (naked_return_label);
5630
5631 /* @@@ This is a kludge. We want to ensure that instructions that
5632 may trap are not moved into the epilogue by scheduling, because
5633 we don't always emit unwind information for the epilogue. */
5634 if (cfun->can_throw_non_call_exceptions
5635 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5636 emit_insn (gen_blockage ());
5637
5638 /* If stack protection is enabled for this function, check the guard. */
5639 if (crtl->stack_protect_guard && targetm.stack_protect_runtime_enabled_p ())
5640 stack_protect_epilogue ();
5641
5642 /* If we had calls to alloca, and this machine needs
5643 an accurate stack pointer to exit the function,
5644 insert some code to save and restore the stack pointer. */
5645 if (! EXIT_IGNORE_STACK
5646 && cfun->calls_alloca)
5647 {
5648 rtx tem = 0;
5649
5650 start_sequence ();
5651 emit_stack_save (SAVE_FUNCTION, &tem);
5652 rtx_insn *seq = get_insns ();
5653 end_sequence ();
5654 emit_insn_before (seq, parm_birth_insn);
5655
5656 emit_stack_restore (SAVE_FUNCTION, tem);
5657 }
5658
5659 /* ??? This should no longer be necessary since stupid is no longer with
5660 us, but there are some parts of the compiler (eg reload_combine, and
5661 sh mach_dep_reorg) that still try and compute their own lifetime info
5662 instead of using the general framework. */
5663 use_return_register ();
5664 }
5665
5666 rtx
5667 get_arg_pointer_save_area (void)
5668 {
5669 rtx ret = arg_pointer_save_area;
5670
5671 if (! ret)
5672 {
5673 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5674 arg_pointer_save_area = ret;
5675 }
5676
5677 if (! crtl->arg_pointer_save_area_init)
5678 {
5679 /* Save the arg pointer at the beginning of the function. The
5680 generated stack slot may not be a valid memory address, so we
5681 have to check it and fix it if necessary. */
5682 start_sequence ();
5683 emit_move_insn (validize_mem (copy_rtx (ret)),
5684 crtl->args.internal_arg_pointer);
5685 rtx_insn *seq = get_insns ();
5686 end_sequence ();
5687
5688 push_topmost_sequence ();
5689 emit_insn_after (seq, entry_of_function ());
5690 pop_topmost_sequence ();
5691
5692 crtl->arg_pointer_save_area_init = true;
5693 }
5694
5695 return ret;
5696 }
5697 \f
5698
5699 /* If debugging dumps are requested, dump information about how the
5700 target handled -fstack-check=clash for the prologue.
5701
5702 PROBES describes what if any probes were emitted.
5703
5704 RESIDUALS indicates if the prologue had any residual allocation
5705 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5706
5707 void
5708 dump_stack_clash_frame_info (enum stack_clash_probes probes, bool residuals)
5709 {
5710 if (!dump_file)
5711 return;
5712
5713 switch (probes)
5714 {
5715 case NO_PROBE_NO_FRAME:
5716 fprintf (dump_file,
5717 "Stack clash no probe no stack adjustment in prologue.\n");
5718 break;
5719 case NO_PROBE_SMALL_FRAME:
5720 fprintf (dump_file,
5721 "Stack clash no probe small stack adjustment in prologue.\n");
5722 break;
5723 case PROBE_INLINE:
5724 fprintf (dump_file, "Stack clash inline probes in prologue.\n");
5725 break;
5726 case PROBE_LOOP:
5727 fprintf (dump_file, "Stack clash probe loop in prologue.\n");
5728 break;
5729 }
5730
5731 if (residuals)
5732 fprintf (dump_file, "Stack clash residual allocation in prologue.\n");
5733 else
5734 fprintf (dump_file, "Stack clash no residual allocation in prologue.\n");
5735
5736 if (frame_pointer_needed)
5737 fprintf (dump_file, "Stack clash frame pointer needed.\n");
5738 else
5739 fprintf (dump_file, "Stack clash no frame pointer needed.\n");
5740
5741 if (TREE_THIS_VOLATILE (cfun->decl))
5742 fprintf (dump_file,
5743 "Stack clash noreturn prologue, assuming no implicit"
5744 " probes in caller.\n");
5745 else
5746 fprintf (dump_file,
5747 "Stack clash not noreturn prologue.\n");
5748 }
5749
5750 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5751 for the first time. */
5752
5753 static void
5754 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5755 {
5756 rtx_insn *tmp;
5757 hash_table<insn_cache_hasher> *hash = *hashp;
5758
5759 if (hash == NULL)
5760 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5761
5762 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5763 {
5764 rtx *slot = hash->find_slot (tmp, INSERT);
5765 gcc_assert (*slot == NULL);
5766 *slot = tmp;
5767 }
5768 }
5769
5770 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5771 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5772 insn, then record COPY as well. */
5773
5774 void
5775 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5776 {
5777 hash_table<insn_cache_hasher> *hash;
5778 rtx *slot;
5779
5780 hash = epilogue_insn_hash;
5781 if (!hash || !hash->find (insn))
5782 {
5783 hash = prologue_insn_hash;
5784 if (!hash || !hash->find (insn))
5785 return;
5786 }
5787
5788 slot = hash->find_slot (copy, INSERT);
5789 gcc_assert (*slot == NULL);
5790 *slot = copy;
5791 }
5792
5793 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5794 we can be running after reorg, SEQUENCE rtl is possible. */
5795
5796 static bool
5797 contains (const rtx_insn *insn, hash_table<insn_cache_hasher> *hash)
5798 {
5799 if (hash == NULL)
5800 return false;
5801
5802 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5803 {
5804 rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn));
5805 int i;
5806 for (i = seq->len () - 1; i >= 0; i--)
5807 if (hash->find (seq->element (i)))
5808 return true;
5809 return false;
5810 }
5811
5812 return hash->find (const_cast<rtx_insn *> (insn)) != NULL;
5813 }
5814
5815 int
5816 prologue_contains (const rtx_insn *insn)
5817 {
5818 return contains (insn, prologue_insn_hash);
5819 }
5820
5821 int
5822 epilogue_contains (const rtx_insn *insn)
5823 {
5824 return contains (insn, epilogue_insn_hash);
5825 }
5826
5827 int
5828 prologue_epilogue_contains (const rtx_insn *insn)
5829 {
5830 if (contains (insn, prologue_insn_hash))
5831 return 1;
5832 if (contains (insn, epilogue_insn_hash))
5833 return 1;
5834 return 0;
5835 }
5836
5837 void
5838 record_prologue_seq (rtx_insn *seq)
5839 {
5840 record_insns (seq, NULL, &prologue_insn_hash);
5841 }
5842
5843 void
5844 record_epilogue_seq (rtx_insn *seq)
5845 {
5846 record_insns (seq, NULL, &epilogue_insn_hash);
5847 }
5848
5849 /* Set JUMP_LABEL for a return insn. */
5850
5851 void
5852 set_return_jump_label (rtx_insn *returnjump)
5853 {
5854 rtx pat = PATTERN (returnjump);
5855 if (GET_CODE (pat) == PARALLEL)
5856 pat = XVECEXP (pat, 0, 0);
5857 if (ANY_RETURN_P (pat))
5858 JUMP_LABEL (returnjump) = pat;
5859 else
5860 JUMP_LABEL (returnjump) = ret_rtx;
5861 }
5862
5863 /* Return a sequence to be used as the split prologue for the current
5864 function, or NULL. */
5865
5866 static rtx_insn *
5867 make_split_prologue_seq (void)
5868 {
5869 if (!flag_split_stack
5870 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl)))
5871 return NULL;
5872
5873 start_sequence ();
5874 emit_insn (targetm.gen_split_stack_prologue ());
5875 rtx_insn *seq = get_insns ();
5876 end_sequence ();
5877
5878 record_insns (seq, NULL, &prologue_insn_hash);
5879 set_insn_locations (seq, prologue_location);
5880
5881 return seq;
5882 }
5883
5884 /* Return a sequence to be used as the prologue for the current function,
5885 or NULL. */
5886
5887 static rtx_insn *
5888 make_prologue_seq (void)
5889 {
5890 if (!targetm.have_prologue ())
5891 return NULL;
5892
5893 start_sequence ();
5894 rtx_insn *seq = targetm.gen_prologue ();
5895 emit_insn (seq);
5896
5897 /* Insert an explicit USE for the frame pointer
5898 if the profiling is on and the frame pointer is required. */
5899 if (crtl->profile && frame_pointer_needed)
5900 emit_use (hard_frame_pointer_rtx);
5901
5902 /* Retain a map of the prologue insns. */
5903 record_insns (seq, NULL, &prologue_insn_hash);
5904 emit_note (NOTE_INSN_PROLOGUE_END);
5905
5906 /* Ensure that instructions are not moved into the prologue when
5907 profiling is on. The call to the profiling routine can be
5908 emitted within the live range of a call-clobbered register. */
5909 if (!targetm.profile_before_prologue () && crtl->profile)
5910 emit_insn (gen_blockage ());
5911
5912 seq = get_insns ();
5913 end_sequence ();
5914 set_insn_locations (seq, prologue_location);
5915
5916 return seq;
5917 }
5918
5919 /* Return a sequence to be used as the epilogue for the current function,
5920 or NULL. */
5921
5922 static rtx_insn *
5923 make_epilogue_seq (void)
5924 {
5925 if (!targetm.have_epilogue ())
5926 return NULL;
5927
5928 start_sequence ();
5929 emit_note (NOTE_INSN_EPILOGUE_BEG);
5930 rtx_insn *seq = targetm.gen_epilogue ();
5931 if (seq)
5932 emit_jump_insn (seq);
5933
5934 /* Retain a map of the epilogue insns. */
5935 record_insns (seq, NULL, &epilogue_insn_hash);
5936 set_insn_locations (seq, epilogue_location);
5937
5938 seq = get_insns ();
5939 rtx_insn *returnjump = get_last_insn ();
5940 end_sequence ();
5941
5942 if (JUMP_P (returnjump))
5943 set_return_jump_label (returnjump);
5944
5945 return seq;
5946 }
5947
5948
5949 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5950 this into place with notes indicating where the prologue ends and where
5951 the epilogue begins. Update the basic block information when possible.
5952
5953 Notes on epilogue placement:
5954 There are several kinds of edges to the exit block:
5955 * a single fallthru edge from LAST_BB
5956 * possibly, edges from blocks containing sibcalls
5957 * possibly, fake edges from infinite loops
5958
5959 The epilogue is always emitted on the fallthru edge from the last basic
5960 block in the function, LAST_BB, into the exit block.
5961
5962 If LAST_BB is empty except for a label, it is the target of every
5963 other basic block in the function that ends in a return. If a
5964 target has a return or simple_return pattern (possibly with
5965 conditional variants), these basic blocks can be changed so that a
5966 return insn is emitted into them, and their target is adjusted to
5967 the real exit block.
5968
5969 Notes on shrink wrapping: We implement a fairly conservative
5970 version of shrink-wrapping rather than the textbook one. We only
5971 generate a single prologue and a single epilogue. This is
5972 sufficient to catch a number of interesting cases involving early
5973 exits.
5974
5975 First, we identify the blocks that require the prologue to occur before
5976 them. These are the ones that modify a call-saved register, or reference
5977 any of the stack or frame pointer registers. To simplify things, we then
5978 mark everything reachable from these blocks as also requiring a prologue.
5979 This takes care of loops automatically, and avoids the need to examine
5980 whether MEMs reference the frame, since it is sufficient to check for
5981 occurrences of the stack or frame pointer.
5982
5983 We then compute the set of blocks for which the need for a prologue
5984 is anticipatable (borrowing terminology from the shrink-wrapping
5985 description in Muchnick's book). These are the blocks which either
5986 require a prologue themselves, or those that have only successors
5987 where the prologue is anticipatable. The prologue needs to be
5988 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5989 is not. For the moment, we ensure that only one such edge exists.
5990
5991 The epilogue is placed as described above, but we make a
5992 distinction between inserting return and simple_return patterns
5993 when modifying other blocks that end in a return. Blocks that end
5994 in a sibcall omit the sibcall_epilogue if the block is not in
5995 ANTIC. */
5996
5997 void
5998 thread_prologue_and_epilogue_insns (void)
5999 {
6000 df_analyze ();
6001
6002 /* Can't deal with multiple successors of the entry block at the
6003 moment. Function should always have at least one entry
6004 point. */
6005 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
6006
6007 edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
6008 edge orig_entry_edge = entry_edge;
6009
6010 rtx_insn *split_prologue_seq = make_split_prologue_seq ();
6011 rtx_insn *prologue_seq = make_prologue_seq ();
6012 rtx_insn *epilogue_seq = make_epilogue_seq ();
6013
6014 /* Try to perform a kind of shrink-wrapping, making sure the
6015 prologue/epilogue is emitted only around those parts of the
6016 function that require it. */
6017 try_shrink_wrapping (&entry_edge, prologue_seq);
6018
6019 /* If the target can handle splitting the prologue/epilogue into separate
6020 components, try to shrink-wrap these components separately. */
6021 try_shrink_wrapping_separate (entry_edge->dest);
6022
6023 /* If that did anything for any component we now need the generate the
6024 "main" prologue again. Because some targets require some of these
6025 to be called in a specific order (i386 requires the split prologue
6026 to be first, for example), we create all three sequences again here.
6027 If this does not work for some target, that target should not enable
6028 separate shrink-wrapping. */
6029 if (crtl->shrink_wrapped_separate)
6030 {
6031 split_prologue_seq = make_split_prologue_seq ();
6032 prologue_seq = make_prologue_seq ();
6033 epilogue_seq = make_epilogue_seq ();
6034 }
6035
6036 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
6037
6038 /* A small fib -- epilogue is not yet completed, but we wish to re-use
6039 this marker for the splits of EH_RETURN patterns, and nothing else
6040 uses the flag in the meantime. */
6041 epilogue_completed = 1;
6042
6043 /* Find non-fallthru edges that end with EH_RETURN instructions. On
6044 some targets, these get split to a special version of the epilogue
6045 code. In order to be able to properly annotate these with unwind
6046 info, try to split them now. If we get a valid split, drop an
6047 EPILOGUE_BEG note and mark the insns as epilogue insns. */
6048 edge e;
6049 edge_iterator ei;
6050 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6051 {
6052 rtx_insn *prev, *last, *trial;
6053
6054 if (e->flags & EDGE_FALLTHRU)
6055 continue;
6056 last = BB_END (e->src);
6057 if (!eh_returnjump_p (last))
6058 continue;
6059
6060 prev = PREV_INSN (last);
6061 trial = try_split (PATTERN (last), last, 1);
6062 if (trial == last)
6063 continue;
6064
6065 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
6066 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
6067 }
6068
6069 edge exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6070
6071 if (exit_fallthru_edge)
6072 {
6073 if (epilogue_seq)
6074 {
6075 insert_insn_on_edge (epilogue_seq, exit_fallthru_edge);
6076 commit_edge_insertions ();
6077
6078 /* The epilogue insns we inserted may cause the exit edge to no longer
6079 be fallthru. */
6080 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6081 {
6082 if (((e->flags & EDGE_FALLTHRU) != 0)
6083 && returnjump_p (BB_END (e->src)))
6084 e->flags &= ~EDGE_FALLTHRU;
6085 }
6086 }
6087 else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
6088 {
6089 /* We have a fall-through edge to the exit block, the source is not
6090 at the end of the function, and there will be an assembler epilogue
6091 at the end of the function.
6092 We can't use force_nonfallthru here, because that would try to
6093 use return. Inserting a jump 'by hand' is extremely messy, so
6094 we take advantage of cfg_layout_finalize using
6095 fixup_fallthru_exit_predecessor. */
6096 cfg_layout_initialize (0);
6097 basic_block cur_bb;
6098 FOR_EACH_BB_FN (cur_bb, cfun)
6099 if (cur_bb->index >= NUM_FIXED_BLOCKS
6100 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
6101 cur_bb->aux = cur_bb->next_bb;
6102 cfg_layout_finalize ();
6103 }
6104 }
6105
6106 /* Insert the prologue. */
6107
6108 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
6109
6110 if (split_prologue_seq || prologue_seq)
6111 {
6112 rtx_insn *split_prologue_insn = split_prologue_seq;
6113 if (split_prologue_seq)
6114 {
6115 while (split_prologue_insn && !NONDEBUG_INSN_P (split_prologue_insn))
6116 split_prologue_insn = NEXT_INSN (split_prologue_insn);
6117 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
6118 }
6119
6120 rtx_insn *prologue_insn = prologue_seq;
6121 if (prologue_seq)
6122 {
6123 while (prologue_insn && !NONDEBUG_INSN_P (prologue_insn))
6124 prologue_insn = NEXT_INSN (prologue_insn);
6125 insert_insn_on_edge (prologue_seq, entry_edge);
6126 }
6127
6128 commit_edge_insertions ();
6129
6130 /* Look for basic blocks within the prologue insns. */
6131 if (split_prologue_insn
6132 && BLOCK_FOR_INSN (split_prologue_insn) == NULL)
6133 split_prologue_insn = NULL;
6134 if (prologue_insn
6135 && BLOCK_FOR_INSN (prologue_insn) == NULL)
6136 prologue_insn = NULL;
6137 if (split_prologue_insn || prologue_insn)
6138 {
6139 auto_sbitmap blocks (last_basic_block_for_fn (cfun));
6140 bitmap_clear (blocks);
6141 if (split_prologue_insn)
6142 bitmap_set_bit (blocks,
6143 BLOCK_FOR_INSN (split_prologue_insn)->index);
6144 if (prologue_insn)
6145 bitmap_set_bit (blocks, BLOCK_FOR_INSN (prologue_insn)->index);
6146 find_many_sub_basic_blocks (blocks);
6147 }
6148 }
6149
6150 default_rtl_profile ();
6151
6152 /* Emit sibling epilogues before any sibling call sites. */
6153 for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6154 (e = ei_safe_edge (ei));
6155 ei_next (&ei))
6156 {
6157 /* Skip those already handled, the ones that run without prologue. */
6158 if (e->flags & EDGE_IGNORE)
6159 {
6160 e->flags &= ~EDGE_IGNORE;
6161 continue;
6162 }
6163
6164 rtx_insn *insn = BB_END (e->src);
6165
6166 if (!(CALL_P (insn) && SIBLING_CALL_P (insn)))
6167 continue;
6168
6169 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6170 {
6171 start_sequence ();
6172 emit_note (NOTE_INSN_EPILOGUE_BEG);
6173 emit_insn (ep_seq);
6174 rtx_insn *seq = get_insns ();
6175 end_sequence ();
6176
6177 /* Retain a map of the epilogue insns. Used in life analysis to
6178 avoid getting rid of sibcall epilogue insns. Do this before we
6179 actually emit the sequence. */
6180 record_insns (seq, NULL, &epilogue_insn_hash);
6181 set_insn_locations (seq, epilogue_location);
6182
6183 emit_insn_before (seq, insn);
6184 }
6185 }
6186
6187 if (epilogue_seq)
6188 {
6189 rtx_insn *insn, *next;
6190
6191 /* Similarly, move any line notes that appear after the epilogue.
6192 There is no need, however, to be quite so anal about the existence
6193 of such a note. Also possibly move
6194 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6195 info generation. */
6196 for (insn = epilogue_seq; insn; insn = next)
6197 {
6198 next = NEXT_INSN (insn);
6199 if (NOTE_P (insn)
6200 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6201 reorder_insns (insn, insn, PREV_INSN (epilogue_seq));
6202 }
6203 }
6204
6205 /* Threading the prologue and epilogue changes the artificial refs
6206 in the entry and exit blocks. */
6207 epilogue_completed = 1;
6208 df_update_entry_exit_and_calls ();
6209 }
6210
6211 /* Reposition the prologue-end and epilogue-begin notes after
6212 instruction scheduling. */
6213
6214 void
6215 reposition_prologue_and_epilogue_notes (void)
6216 {
6217 if (!targetm.have_prologue ()
6218 && !targetm.have_epilogue ()
6219 && !targetm.have_sibcall_epilogue ())
6220 return;
6221
6222 /* Since the hash table is created on demand, the fact that it is
6223 non-null is a signal that it is non-empty. */
6224 if (prologue_insn_hash != NULL)
6225 {
6226 size_t len = prologue_insn_hash->elements ();
6227 rtx_insn *insn, *last = NULL, *note = NULL;
6228
6229 /* Scan from the beginning until we reach the last prologue insn. */
6230 /* ??? While we do have the CFG intact, there are two problems:
6231 (1) The prologue can contain loops (typically probing the stack),
6232 which means that the end of the prologue isn't in the first bb.
6233 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6234 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6235 {
6236 if (NOTE_P (insn))
6237 {
6238 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6239 note = insn;
6240 }
6241 else if (contains (insn, prologue_insn_hash))
6242 {
6243 last = insn;
6244 if (--len == 0)
6245 break;
6246 }
6247 }
6248
6249 if (last)
6250 {
6251 if (note == NULL)
6252 {
6253 /* Scan forward looking for the PROLOGUE_END note. It should
6254 be right at the beginning of the block, possibly with other
6255 insn notes that got moved there. */
6256 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6257 {
6258 if (NOTE_P (note)
6259 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6260 break;
6261 }
6262 }
6263
6264 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6265 if (LABEL_P (last))
6266 last = NEXT_INSN (last);
6267 reorder_insns (note, note, last);
6268 }
6269 }
6270
6271 if (epilogue_insn_hash != NULL)
6272 {
6273 edge_iterator ei;
6274 edge e;
6275
6276 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6277 {
6278 rtx_insn *insn, *first = NULL, *note = NULL;
6279 basic_block bb = e->src;
6280
6281 /* Scan from the beginning until we reach the first epilogue insn. */
6282 FOR_BB_INSNS (bb, insn)
6283 {
6284 if (NOTE_P (insn))
6285 {
6286 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6287 {
6288 note = insn;
6289 if (first != NULL)
6290 break;
6291 }
6292 }
6293 else if (first == NULL && contains (insn, epilogue_insn_hash))
6294 {
6295 first = insn;
6296 if (note != NULL)
6297 break;
6298 }
6299 }
6300
6301 if (note)
6302 {
6303 /* If the function has a single basic block, and no real
6304 epilogue insns (e.g. sibcall with no cleanup), the
6305 epilogue note can get scheduled before the prologue
6306 note. If we have frame related prologue insns, having
6307 them scanned during the epilogue will result in a crash.
6308 In this case re-order the epilogue note to just before
6309 the last insn in the block. */
6310 if (first == NULL)
6311 first = BB_END (bb);
6312
6313 if (PREV_INSN (first) != note)
6314 reorder_insns (note, note, PREV_INSN (first));
6315 }
6316 }
6317 }
6318 }
6319
6320 /* Returns the name of function declared by FNDECL. */
6321 const char *
6322 fndecl_name (tree fndecl)
6323 {
6324 if (fndecl == NULL)
6325 return "(nofn)";
6326 return lang_hooks.decl_printable_name (fndecl, 1);
6327 }
6328
6329 /* Returns the name of function FN. */
6330 const char *
6331 function_name (struct function *fn)
6332 {
6333 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6334 return fndecl_name (fndecl);
6335 }
6336
6337 /* Returns the name of the current function. */
6338 const char *
6339 current_function_name (void)
6340 {
6341 return function_name (cfun);
6342 }
6343 \f
6344
6345 static unsigned int
6346 rest_of_handle_check_leaf_regs (void)
6347 {
6348 #ifdef LEAF_REGISTERS
6349 crtl->uses_only_leaf_regs
6350 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6351 #endif
6352 return 0;
6353 }
6354
6355 /* Insert a TYPE into the used types hash table of CFUN. */
6356
6357 static void
6358 used_types_insert_helper (tree type, struct function *func)
6359 {
6360 if (type != NULL && func != NULL)
6361 {
6362 if (func->used_types_hash == NULL)
6363 func->used_types_hash = hash_set<tree>::create_ggc (37);
6364
6365 func->used_types_hash->add (type);
6366 }
6367 }
6368
6369 /* Given a type, insert it into the used hash table in cfun. */
6370 void
6371 used_types_insert (tree t)
6372 {
6373 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6374 if (TYPE_NAME (t))
6375 break;
6376 else
6377 t = TREE_TYPE (t);
6378 if (TREE_CODE (t) == ERROR_MARK)
6379 return;
6380 if (TYPE_NAME (t) == NULL_TREE
6381 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6382 t = TYPE_MAIN_VARIANT (t);
6383 if (debug_info_level > DINFO_LEVEL_NONE)
6384 {
6385 if (cfun)
6386 used_types_insert_helper (t, cfun);
6387 else
6388 {
6389 /* So this might be a type referenced by a global variable.
6390 Record that type so that we can later decide to emit its
6391 debug information. */
6392 vec_safe_push (types_used_by_cur_var_decl, t);
6393 }
6394 }
6395 }
6396
6397 /* Helper to Hash a struct types_used_by_vars_entry. */
6398
6399 static hashval_t
6400 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6401 {
6402 gcc_assert (entry && entry->var_decl && entry->type);
6403
6404 return iterative_hash_object (entry->type,
6405 iterative_hash_object (entry->var_decl, 0));
6406 }
6407
6408 /* Hash function of the types_used_by_vars_entry hash table. */
6409
6410 hashval_t
6411 used_type_hasher::hash (types_used_by_vars_entry *entry)
6412 {
6413 return hash_types_used_by_vars_entry (entry);
6414 }
6415
6416 /*Equality function of the types_used_by_vars_entry hash table. */
6417
6418 bool
6419 used_type_hasher::equal (types_used_by_vars_entry *e1,
6420 types_used_by_vars_entry *e2)
6421 {
6422 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6423 }
6424
6425 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6426
6427 void
6428 types_used_by_var_decl_insert (tree type, tree var_decl)
6429 {
6430 if (type != NULL && var_decl != NULL)
6431 {
6432 types_used_by_vars_entry **slot;
6433 struct types_used_by_vars_entry e;
6434 e.var_decl = var_decl;
6435 e.type = type;
6436 if (types_used_by_vars_hash == NULL)
6437 types_used_by_vars_hash
6438 = hash_table<used_type_hasher>::create_ggc (37);
6439
6440 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6441 if (*slot == NULL)
6442 {
6443 struct types_used_by_vars_entry *entry;
6444 entry = ggc_alloc<types_used_by_vars_entry> ();
6445 entry->type = type;
6446 entry->var_decl = var_decl;
6447 *slot = entry;
6448 }
6449 }
6450 }
6451
6452 namespace {
6453
6454 const pass_data pass_data_leaf_regs =
6455 {
6456 RTL_PASS, /* type */
6457 "*leaf_regs", /* name */
6458 OPTGROUP_NONE, /* optinfo_flags */
6459 TV_NONE, /* tv_id */
6460 0, /* properties_required */
6461 0, /* properties_provided */
6462 0, /* properties_destroyed */
6463 0, /* todo_flags_start */
6464 0, /* todo_flags_finish */
6465 };
6466
6467 class pass_leaf_regs : public rtl_opt_pass
6468 {
6469 public:
6470 pass_leaf_regs (gcc::context *ctxt)
6471 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6472 {}
6473
6474 /* opt_pass methods: */
6475 virtual unsigned int execute (function *)
6476 {
6477 return rest_of_handle_check_leaf_regs ();
6478 }
6479
6480 }; // class pass_leaf_regs
6481
6482 } // anon namespace
6483
6484 rtl_opt_pass *
6485 make_pass_leaf_regs (gcc::context *ctxt)
6486 {
6487 return new pass_leaf_regs (ctxt);
6488 }
6489
6490 static unsigned int
6491 rest_of_handle_thread_prologue_and_epilogue (void)
6492 {
6493 /* prepare_shrink_wrap is sensitive to the block structure of the control
6494 flow graph, so clean it up first. */
6495 if (optimize)
6496 cleanup_cfg (0);
6497
6498 /* On some machines, the prologue and epilogue code, or parts thereof,
6499 can be represented as RTL. Doing so lets us schedule insns between
6500 it and the rest of the code and also allows delayed branch
6501 scheduling to operate in the epilogue. */
6502 thread_prologue_and_epilogue_insns ();
6503
6504 /* Some non-cold blocks may now be only reachable from cold blocks.
6505 Fix that up. */
6506 fixup_partitions ();
6507
6508 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6509 see PR57320. */
6510 cleanup_cfg (optimize ? CLEANUP_EXPENSIVE : 0);
6511
6512 /* The stack usage info is finalized during prologue expansion. */
6513 if (flag_stack_usage_info)
6514 output_stack_usage ();
6515
6516 return 0;
6517 }
6518
6519 namespace {
6520
6521 const pass_data pass_data_thread_prologue_and_epilogue =
6522 {
6523 RTL_PASS, /* type */
6524 "pro_and_epilogue", /* name */
6525 OPTGROUP_NONE, /* optinfo_flags */
6526 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6527 0, /* properties_required */
6528 0, /* properties_provided */
6529 0, /* properties_destroyed */
6530 0, /* todo_flags_start */
6531 ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
6532 };
6533
6534 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6535 {
6536 public:
6537 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6538 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6539 {}
6540
6541 /* opt_pass methods: */
6542 virtual unsigned int execute (function *)
6543 {
6544 return rest_of_handle_thread_prologue_and_epilogue ();
6545 }
6546
6547 }; // class pass_thread_prologue_and_epilogue
6548
6549 } // anon namespace
6550
6551 rtl_opt_pass *
6552 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6553 {
6554 return new pass_thread_prologue_and_epilogue (ctxt);
6555 }
6556 \f
6557
6558 /* This mini-pass fixes fall-out from SSA in asm statements that have
6559 in-out constraints. Say you start with
6560
6561 orig = inout;
6562 asm ("": "+mr" (inout));
6563 use (orig);
6564
6565 which is transformed very early to use explicit output and match operands:
6566
6567 orig = inout;
6568 asm ("": "=mr" (inout) : "0" (inout));
6569 use (orig);
6570
6571 Or, after SSA and copyprop,
6572
6573 asm ("": "=mr" (inout_2) : "0" (inout_1));
6574 use (inout_1);
6575
6576 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6577 they represent two separate values, so they will get different pseudo
6578 registers during expansion. Then, since the two operands need to match
6579 per the constraints, but use different pseudo registers, reload can
6580 only register a reload for these operands. But reloads can only be
6581 satisfied by hardregs, not by memory, so we need a register for this
6582 reload, just because we are presented with non-matching operands.
6583 So, even though we allow memory for this operand, no memory can be
6584 used for it, just because the two operands don't match. This can
6585 cause reload failures on register-starved targets.
6586
6587 So it's a symptom of reload not being able to use memory for reloads
6588 or, alternatively it's also a symptom of both operands not coming into
6589 reload as matching (in which case the pseudo could go to memory just
6590 fine, as the alternative allows it, and no reload would be necessary).
6591 We fix the latter problem here, by transforming
6592
6593 asm ("": "=mr" (inout_2) : "0" (inout_1));
6594
6595 back to
6596
6597 inout_2 = inout_1;
6598 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6599
6600 static void
6601 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
6602 {
6603 int i;
6604 bool changed = false;
6605 rtx op = SET_SRC (p_sets[0]);
6606 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6607 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6608 bool *output_matched = XALLOCAVEC (bool, noutputs);
6609
6610 memset (output_matched, 0, noutputs * sizeof (bool));
6611 for (i = 0; i < ninputs; i++)
6612 {
6613 rtx input, output;
6614 rtx_insn *insns;
6615 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6616 char *end;
6617 int match, j;
6618
6619 if (*constraint == '%')
6620 constraint++;
6621
6622 match = strtoul (constraint, &end, 10);
6623 if (end == constraint)
6624 continue;
6625
6626 gcc_assert (match < noutputs);
6627 output = SET_DEST (p_sets[match]);
6628 input = RTVEC_ELT (inputs, i);
6629 /* Only do the transformation for pseudos. */
6630 if (! REG_P (output)
6631 || rtx_equal_p (output, input)
6632 || (GET_MODE (input) != VOIDmode
6633 && GET_MODE (input) != GET_MODE (output)))
6634 continue;
6635
6636 /* We can't do anything if the output is also used as input,
6637 as we're going to overwrite it. */
6638 for (j = 0; j < ninputs; j++)
6639 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6640 break;
6641 if (j != ninputs)
6642 continue;
6643
6644 /* Avoid changing the same input several times. For
6645 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6646 only change in once (to out1), rather than changing it
6647 first to out1 and afterwards to out2. */
6648 if (i > 0)
6649 {
6650 for (j = 0; j < noutputs; j++)
6651 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6652 break;
6653 if (j != noutputs)
6654 continue;
6655 }
6656 output_matched[match] = true;
6657
6658 start_sequence ();
6659 emit_move_insn (output, input);
6660 insns = get_insns ();
6661 end_sequence ();
6662 emit_insn_before (insns, insn);
6663
6664 /* Now replace all mentions of the input with output. We can't
6665 just replace the occurrence in inputs[i], as the register might
6666 also be used in some other input (or even in an address of an
6667 output), which would mean possibly increasing the number of
6668 inputs by one (namely 'output' in addition), which might pose
6669 a too complicated problem for reload to solve. E.g. this situation:
6670
6671 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6672
6673 Here 'input' is used in two occurrences as input (once for the
6674 input operand, once for the address in the second output operand).
6675 If we would replace only the occurrence of the input operand (to
6676 make the matching) we would be left with this:
6677
6678 output = input
6679 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6680
6681 Now we suddenly have two different input values (containing the same
6682 value, but different pseudos) where we formerly had only one.
6683 With more complicated asms this might lead to reload failures
6684 which wouldn't have happen without this pass. So, iterate over
6685 all operands and replace all occurrences of the register used. */
6686 for (j = 0; j < noutputs; j++)
6687 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6688 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6689 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6690 input, output);
6691 for (j = 0; j < ninputs; j++)
6692 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6693 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6694 input, output);
6695
6696 changed = true;
6697 }
6698
6699 if (changed)
6700 df_insn_rescan (insn);
6701 }
6702
6703 /* Add the decl D to the local_decls list of FUN. */
6704
6705 void
6706 add_local_decl (struct function *fun, tree d)
6707 {
6708 gcc_assert (VAR_P (d));
6709 vec_safe_push (fun->local_decls, d);
6710 }
6711
6712 namespace {
6713
6714 const pass_data pass_data_match_asm_constraints =
6715 {
6716 RTL_PASS, /* type */
6717 "asmcons", /* name */
6718 OPTGROUP_NONE, /* optinfo_flags */
6719 TV_NONE, /* tv_id */
6720 0, /* properties_required */
6721 0, /* properties_provided */
6722 0, /* properties_destroyed */
6723 0, /* todo_flags_start */
6724 0, /* todo_flags_finish */
6725 };
6726
6727 class pass_match_asm_constraints : public rtl_opt_pass
6728 {
6729 public:
6730 pass_match_asm_constraints (gcc::context *ctxt)
6731 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6732 {}
6733
6734 /* opt_pass methods: */
6735 virtual unsigned int execute (function *);
6736
6737 }; // class pass_match_asm_constraints
6738
6739 unsigned
6740 pass_match_asm_constraints::execute (function *fun)
6741 {
6742 basic_block bb;
6743 rtx_insn *insn;
6744 rtx pat, *p_sets;
6745 int noutputs;
6746
6747 if (!crtl->has_asm_statement)
6748 return 0;
6749
6750 df_set_flags (DF_DEFER_INSN_RESCAN);
6751 FOR_EACH_BB_FN (bb, fun)
6752 {
6753 FOR_BB_INSNS (bb, insn)
6754 {
6755 if (!INSN_P (insn))
6756 continue;
6757
6758 pat = PATTERN (insn);
6759 if (GET_CODE (pat) == PARALLEL)
6760 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6761 else if (GET_CODE (pat) == SET)
6762 p_sets = &PATTERN (insn), noutputs = 1;
6763 else
6764 continue;
6765
6766 if (GET_CODE (*p_sets) == SET
6767 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6768 match_asm_constraints_1 (insn, p_sets, noutputs);
6769 }
6770 }
6771
6772 return TODO_df_finish;
6773 }
6774
6775 } // anon namespace
6776
6777 rtl_opt_pass *
6778 make_pass_match_asm_constraints (gcc::context *ctxt)
6779 {
6780 return new pass_match_asm_constraints (ctxt);
6781 }
6782
6783
6784 #include "gt-function.h"