1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2018 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 #include "gimple.h"
83 #include "options.h"
84
85 /* So we can assign to cfun in this file. */
86 #undef cfun
87
88 #ifndef STACK_ALIGNMENT_NEEDED
89 #define STACK_ALIGNMENT_NEEDED 1
90 #endif
91
92 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
93
94 /* Round a value to the lowest integer less than it that is a multiple of
95 the required alignment. Avoid using division in case the value is
96 negative. Assume the alignment is a power of two. */
97 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
98
99 /* Similar, but round to the next highest integer that meets the
100 alignment. */
101 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
102
103 /* Nonzero once virtual register instantiation has been done.
104 assign_stack_local uses frame_pointer_rtx when this is nonzero.
105 calls.c:emit_library_call_value_1 uses it to set up
106 post-instantiation libcalls. */
107 int virtuals_instantiated;
108
109 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
110 static GTY(()) int funcdef_no;
111
112 /* These variables hold pointers to functions to create and destroy
113 target specific, per-function data structures. */
114 struct machine_function * (*init_machine_status) (void);
115
116 /* The currently compiled function. */
117 struct function *cfun = 0;
118
119 /* These hashes record the prologue and epilogue insns. */
120
121 struct insn_cache_hasher : ggc_cache_ptr_hash<rtx_def>
122 {
hashinsn_cache_hasher123 static hashval_t hash (rtx x) { return htab_hash_pointer (x); }
equalinsn_cache_hasher124 static bool equal (rtx a, rtx b) { return a == b; }
125 };
126
127 static GTY((cache))
128 hash_table<insn_cache_hasher> *prologue_insn_hash;
129 static GTY((cache))
130 hash_table<insn_cache_hasher> *epilogue_insn_hash;
131
132
133 hash_table<used_type_hasher> *types_used_by_vars_hash = NULL;
134 vec<tree, va_gc> *types_used_by_cur_var_decl;
135
136 /* Forward declarations. */
137
138 static struct temp_slot *find_temp_slot_from_address (rtx);
139 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
140 static void pad_below (struct args_size *, machine_mode, tree);
141 static void reorder_blocks_1 (rtx_insn *, tree, vec<tree> *);
142 static int all_blocks (tree, tree *);
143 static tree *get_block_vector (tree, int *);
144 extern tree debug_find_var_in_block_tree (tree, tree);
145 /* We always define `record_insns' even if it's not used so that we
146 can always export `prologue_epilogue_contains'. */
147 static void record_insns (rtx_insn *, rtx, hash_table<insn_cache_hasher> **)
148 ATTRIBUTE_UNUSED;
149 static bool contains (const rtx_insn *, hash_table<insn_cache_hasher> *);
150 static void prepare_function_start (void);
151 static void do_clobber_return_reg (rtx, void *);
152 static void do_use_return_reg (rtx, void *);
153
154
155 /* Stack of nested functions. */
156 /* Keep track of the cfun stack. */
157
158 static vec<function *> function_context_stack;
159
160 /* Save the current context for compilation of a nested function.
161 This is called from language-specific code. */
162
163 void
push_function_context(void)164 push_function_context (void)
165 {
166 if (cfun == 0)
167 allocate_struct_function (NULL, false);
168
169 function_context_stack.safe_push (cfun);
170 set_cfun (NULL);
171 }
172
173 /* Restore the last saved context, at the end of a nested function.
174 This function is called from language-specific code. */
175
176 void
pop_function_context(void)177 pop_function_context (void)
178 {
179 struct function *p = function_context_stack.pop ();
180 set_cfun (p);
181 current_function_decl = p->decl;
182
183 /* Reset variables that have known state during rtx generation. */
184 virtuals_instantiated = 0;
185 generating_concat_p = 1;
186 }
187
188 /* Clear out all parts of the state in F that can safely be discarded
189 after the function has been parsed, but not compiled, to let
190 garbage collection reclaim the memory. */
191
192 void
free_after_parsing(struct function * f)193 free_after_parsing (struct function *f)
194 {
195 f->language = 0;
196 }
197
198 /* Clear out all parts of the state in F that can safely be discarded
199 after the function has been compiled, to let garbage collection
200 reclaim the memory. */
201
202 void
free_after_compilation(struct function * f)203 free_after_compilation (struct function *f)
204 {
205 prologue_insn_hash = NULL;
206 epilogue_insn_hash = NULL;
207
208 free (crtl->emit.regno_pointer_align);
209
210 memset (crtl, 0, sizeof (struct rtl_data));
211 f->eh = NULL;
212 f->machine = NULL;
213 f->cfg = NULL;
214 f->curr_properties &= ~PROP_cfg;
215
216 regno_reg_rtx = NULL;
217 }
218
219 /* Return size needed for stack frame based on slots so far allocated.
220 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
221 the caller may have to do that. */
222
223 poly_int64
get_frame_size(void)224 get_frame_size (void)
225 {
226 if (FRAME_GROWS_DOWNWARD)
227 return -frame_offset;
228 else
229 return frame_offset;
230 }
231
232 /* Issue an error message and return TRUE if frame OFFSET overflows in
233 the signed target pointer arithmetics for function FUNC. Otherwise
234 return FALSE. */
235
236 bool
frame_offset_overflow(poly_int64 offset,tree func)237 frame_offset_overflow (poly_int64 offset, tree func)
238 {
239 poly_uint64 size = FRAME_GROWS_DOWNWARD ? -offset : offset;
240 unsigned HOST_WIDE_INT limit
241 = ((HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (Pmode) - 1))
242 /* Leave room for the fixed part of the frame. */
243 - 64 * UNITS_PER_WORD);
244
245 if (!coeffs_in_range_p (size, 0U, limit))
246 {
247 error_at (DECL_SOURCE_LOCATION (func),
248 "total size of local objects too large");
249 return true;
250 }
251
252 return false;
253 }
254
255 /* Return the minimum spill slot alignment for a register of mode MODE. */
256
257 unsigned int
spill_slot_alignment(machine_mode mode ATTRIBUTE_UNUSED)258 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED)
259 {
260 return STACK_SLOT_ALIGNMENT (NULL_TREE, mode, GET_MODE_ALIGNMENT (mode));
261 }
262
263 /* Return stack slot alignment in bits for TYPE and MODE. */
264
265 static unsigned int
get_stack_local_alignment(tree type,machine_mode mode)266 get_stack_local_alignment (tree type, machine_mode mode)
267 {
268 unsigned int alignment;
269
270 if (mode == BLKmode)
271 alignment = BIGGEST_ALIGNMENT;
272 else
273 alignment = GET_MODE_ALIGNMENT (mode);
274
275 /* Allow the frond-end to (possibly) increase the alignment of this
276 stack slot. */
277 if (! type)
278 type = lang_hooks.types.type_for_mode (mode, 0);
279
280 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
281 }
282
283 /* Determine whether it is possible to fit a stack slot of size SIZE and
284 alignment ALIGNMENT into an area in the stack frame that starts at
285 frame offset START and has a length of LENGTH. If so, store the frame
286 offset to be used for the stack slot in *POFFSET and return true;
287 return false otherwise. This function will extend the frame size when
288 given a start/length pair that lies at the end of the frame. */
289
290 static bool
try_fit_stack_local(poly_int64 start,poly_int64 length,poly_int64 size,unsigned int alignment,poly_int64_pod * poffset)291 try_fit_stack_local (poly_int64 start, poly_int64 length,
292 poly_int64 size, unsigned int alignment,
293 poly_int64_pod *poffset)
294 {
295 poly_int64 this_frame_offset;
296 int frame_off, frame_alignment, frame_phase;
297
298 /* Calculate how many bytes the start of local variables is off from
299 stack alignment. */
300 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
301 frame_off = targetm.starting_frame_offset () % frame_alignment;
302 frame_phase = frame_off ? frame_alignment - frame_off : 0;
303
304 /* Round the frame offset to the specified alignment. */
305
306 if (FRAME_GROWS_DOWNWARD)
307 this_frame_offset
308 = (aligned_lower_bound (start + length - size - frame_phase, alignment)
309 + frame_phase);
310 else
311 this_frame_offset
312 = aligned_upper_bound (start - frame_phase, alignment) + frame_phase;
313
314 /* See if it fits. If this space is at the edge of the frame,
315 consider extending the frame to make it fit. Our caller relies on
316 this when allocating a new slot. */
317 if (maybe_lt (this_frame_offset, start))
318 {
319 if (known_eq (frame_offset, start))
320 frame_offset = this_frame_offset;
321 else
322 return false;
323 }
324 else if (maybe_gt (this_frame_offset + size, start + length))
325 {
326 if (known_eq (frame_offset, start + length))
327 frame_offset = this_frame_offset + size;
328 else
329 return false;
330 }
331
332 *poffset = this_frame_offset;
333 return true;
334 }
335
336 /* Create a new frame_space structure describing free space in the stack
337 frame beginning at START and ending at END, and chain it into the
338 function's frame_space_list. */
339
340 static void
add_frame_space(poly_int64 start,poly_int64 end)341 add_frame_space (poly_int64 start, poly_int64 end)
342 {
343 struct frame_space *space = ggc_alloc<frame_space> ();
344 space->next = crtl->frame_space_list;
345 crtl->frame_space_list = space;
346 space->start = start;
347 space->length = end - start;
348 }
349
350 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
351 with machine mode MODE.
352
353 ALIGN controls the amount of alignment for the address of the slot:
354 0 means according to MODE,
355 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
356 -2 means use BITS_PER_UNIT,
357 positive specifies alignment boundary in bits.
358
359 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
360 alignment and ASLK_RECORD_PAD bit set if we should remember
361 extra space we allocated for alignment purposes. When we are
362 called from assign_stack_temp_for_type, it is not set so we don't
363 track the same stack slot in two independent lists.
364
365 We do not round to stack_boundary here. */
366
367 rtx
assign_stack_local_1(machine_mode mode,poly_int64 size,int align,int kind)368 assign_stack_local_1 (machine_mode mode, poly_int64 size,
369 int align, int kind)
370 {
371 rtx x, addr;
372 poly_int64 bigend_correction = 0;
373 poly_int64 slot_offset = 0, old_frame_offset;
374 unsigned int alignment, alignment_in_bits;
375
376 if (align == 0)
377 {
378 alignment = get_stack_local_alignment (NULL, mode);
379 alignment /= BITS_PER_UNIT;
380 }
381 else if (align == -1)
382 {
383 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
384 size = aligned_upper_bound (size, alignment);
385 }
386 else if (align == -2)
387 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
388 else
389 alignment = align / BITS_PER_UNIT;
390
391 alignment_in_bits = alignment * BITS_PER_UNIT;
392
393 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
394 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
395 {
396 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
397 alignment = alignment_in_bits / BITS_PER_UNIT;
398 }
399
400 if (SUPPORTS_STACK_ALIGNMENT)
401 {
402 if (crtl->stack_alignment_estimated < alignment_in_bits)
403 {
404 if (!crtl->stack_realign_processed)
405 crtl->stack_alignment_estimated = alignment_in_bits;
406 else
407 {
408 /* If stack is realigned and stack alignment value
409 hasn't been finalized, it is OK not to increase
410 stack_alignment_estimated. The bigger alignment
411 requirement is recorded in stack_alignment_needed
412 below. */
413 gcc_assert (!crtl->stack_realign_finalized);
414 if (!crtl->stack_realign_needed)
415 {
416 /* It is OK to reduce the alignment as long as the
417 requested size is 0 or the estimated stack
418 alignment >= mode alignment. */
419 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
420 || known_eq (size, 0)
421 || (crtl->stack_alignment_estimated
422 >= GET_MODE_ALIGNMENT (mode)));
423 alignment_in_bits = crtl->stack_alignment_estimated;
424 alignment = alignment_in_bits / BITS_PER_UNIT;
425 }
426 }
427 }
428 }
429
430 if (crtl->stack_alignment_needed < alignment_in_bits)
431 crtl->stack_alignment_needed = alignment_in_bits;
432 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
433 crtl->max_used_stack_slot_alignment = alignment_in_bits;
434
435 if (mode != BLKmode || maybe_ne (size, 0))
436 {
437 if (kind & ASLK_RECORD_PAD)
438 {
439 struct frame_space **psp;
440
441 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
442 {
443 struct frame_space *space = *psp;
444 if (!try_fit_stack_local (space->start, space->length, size,
445 alignment, &slot_offset))
446 continue;
447 *psp = space->next;
448 if (known_gt (slot_offset, space->start))
449 add_frame_space (space->start, slot_offset);
450 if (known_lt (slot_offset + size, space->start + space->length))
451 add_frame_space (slot_offset + size,
452 space->start + space->length);
453 goto found_space;
454 }
455 }
456 }
457 else if (!STACK_ALIGNMENT_NEEDED)
458 {
459 slot_offset = frame_offset;
460 goto found_space;
461 }
462
463 old_frame_offset = frame_offset;
464
465 if (FRAME_GROWS_DOWNWARD)
466 {
467 frame_offset -= size;
468 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
469
470 if (kind & ASLK_RECORD_PAD)
471 {
472 if (known_gt (slot_offset, frame_offset))
473 add_frame_space (frame_offset, slot_offset);
474 if (known_lt (slot_offset + size, old_frame_offset))
475 add_frame_space (slot_offset + size, old_frame_offset);
476 }
477 }
478 else
479 {
480 frame_offset += size;
481 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
482
483 if (kind & ASLK_RECORD_PAD)
484 {
485 if (known_gt (slot_offset, old_frame_offset))
486 add_frame_space (old_frame_offset, slot_offset);
487 if (known_lt (slot_offset + size, frame_offset))
488 add_frame_space (slot_offset + size, frame_offset);
489 }
490 }
491
492 found_space:
493 /* On a big-endian machine, if we are allocating more space than we will use,
494 use the least significant bytes of those that are allocated. */
495 if (mode != BLKmode)
496 {
497 /* The slot size can sometimes be smaller than the mode size;
498 e.g. the rs6000 port allocates slots with a vector mode
499 that have the size of only one element. However, the slot
500 size must always be ordered wrt to the mode size, in the
501 same way as for a subreg. */
502 gcc_checking_assert (ordered_p (GET_MODE_SIZE (mode), size));
503 if (BYTES_BIG_ENDIAN && maybe_lt (GET_MODE_SIZE (mode), size))
504 bigend_correction = size - GET_MODE_SIZE (mode);
505 }
506
507 /* If we have already instantiated virtual registers, return the actual
508 address relative to the frame pointer. */
509 if (virtuals_instantiated)
510 addr = plus_constant (Pmode, frame_pointer_rtx,
511 trunc_int_for_mode
512 (slot_offset + bigend_correction
513 + targetm.starting_frame_offset (), Pmode));
514 else
515 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
516 trunc_int_for_mode
517 (slot_offset + bigend_correction,
518 Pmode));
519
520 x = gen_rtx_MEM (mode, addr);
521 set_mem_align (x, alignment_in_bits);
522 MEM_NOTRAP_P (x) = 1;
523
524 vec_safe_push (stack_slot_list, x);
525
526 if (frame_offset_overflow (frame_offset, current_function_decl))
527 frame_offset = 0;
528
529 return x;
530 }
531
532 /* Wrap up assign_stack_local_1 with last parameter as false. */
533
534 rtx
assign_stack_local(machine_mode mode,poly_int64 size,int align)535 assign_stack_local (machine_mode mode, poly_int64 size, int align)
536 {
537 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
538 }
539
540 /* In order to evaluate some expressions, such as function calls returning
541 structures in memory, we need to temporarily allocate stack locations.
542 We record each allocated temporary in the following structure.
543
544 Associated with each temporary slot is a nesting level. When we pop up
545 one level, all temporaries associated with the previous level are freed.
546 Normally, all temporaries are freed after the execution of the statement
547 in which they were created. However, if we are inside a ({...}) grouping,
548 the result may be in a temporary and hence must be preserved. If the
549 result could be in a temporary, we preserve it if we can determine which
550 one it is in. If we cannot determine which temporary may contain the
551 result, all temporaries are preserved. A temporary is preserved by
552 pretending it was allocated at the previous nesting level. */
553
554 struct GTY(()) temp_slot {
555 /* Points to next temporary slot. */
556 struct temp_slot *next;
557 /* Points to previous temporary slot. */
558 struct temp_slot *prev;
559 /* The rtx to used to reference the slot. */
560 rtx slot;
561 /* The size, in units, of the slot. */
562 poly_int64 size;
563 /* The type of the object in the slot, or zero if it doesn't correspond
564 to a type. We use this to determine whether a slot can be reused.
565 It can be reused if objects of the type of the new slot will always
566 conflict with objects of the type of the old slot. */
567 tree type;
568 /* The alignment (in bits) of the slot. */
569 unsigned int align;
570 /* Nonzero if this temporary is currently in use. */
571 char in_use;
572 /* Nesting level at which this slot is being used. */
573 int level;
574 /* The offset of the slot from the frame_pointer, including extra space
575 for alignment. This info is for combine_temp_slots. */
576 poly_int64 base_offset;
577 /* The size of the slot, including extra space for alignment. This
578 info is for combine_temp_slots. */
579 poly_int64 full_size;
580 };
581
582 /* Entry for the below hash table. */
583 struct GTY((for_user)) temp_slot_address_entry {
584 hashval_t hash;
585 rtx address;
586 struct temp_slot *temp_slot;
587 };
588
589 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
590 {
591 static hashval_t hash (temp_slot_address_entry *);
592 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
593 };
594
595 /* A table of addresses that represent a stack slot. The table is a mapping
596 from address RTXen to a temp slot. */
597 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
598 static size_t n_temp_slots_in_use;
599
600 /* Removes temporary slot TEMP from LIST. */
601
602 static void
cut_slot_from_list(struct temp_slot * temp,struct temp_slot ** list)603 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
604 {
605 if (temp->next)
606 temp->next->prev = temp->prev;
607 if (temp->prev)
608 temp->prev->next = temp->next;
609 else
610 *list = temp->next;
611
612 temp->prev = temp->next = NULL;
613 }
614
615 /* Inserts temporary slot TEMP to LIST. */
616
617 static void
insert_slot_to_list(struct temp_slot * temp,struct temp_slot ** list)618 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
619 {
620 temp->next = *list;
621 if (*list)
622 (*list)->prev = temp;
623 temp->prev = NULL;
624 *list = temp;
625 }
626
627 /* Returns the list of used temp slots at LEVEL. */
628
629 static struct temp_slot **
temp_slots_at_level(int level)630 temp_slots_at_level (int level)
631 {
632 if (level >= (int) vec_safe_length (used_temp_slots))
633 vec_safe_grow_cleared (used_temp_slots, level + 1);
634
635 return &(*used_temp_slots)[level];
636 }
637
638 /* Returns the maximal temporary slot level. */
639
640 static int
max_slot_level(void)641 max_slot_level (void)
642 {
643 if (!used_temp_slots)
644 return -1;
645
646 return used_temp_slots->length () - 1;
647 }
648
649 /* Moves temporary slot TEMP to LEVEL. */
650
651 static void
move_slot_to_level(struct temp_slot * temp,int level)652 move_slot_to_level (struct temp_slot *temp, int level)
653 {
654 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
655 insert_slot_to_list (temp, temp_slots_at_level (level));
656 temp->level = level;
657 }
658
659 /* Make temporary slot TEMP available. */
660
661 static void
make_slot_available(struct temp_slot * temp)662 make_slot_available (struct temp_slot *temp)
663 {
664 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
665 insert_slot_to_list (temp, &avail_temp_slots);
666 temp->in_use = 0;
667 temp->level = -1;
668 n_temp_slots_in_use--;
669 }
670
671 /* Compute the hash value for an address -> temp slot mapping.
672 The value is cached on the mapping entry. */
673 static hashval_t
temp_slot_address_compute_hash(struct temp_slot_address_entry * t)674 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
675 {
676 int do_not_record = 0;
677 return hash_rtx (t->address, GET_MODE (t->address),
678 &do_not_record, NULL, false);
679 }
680
681 /* Return the hash value for an address -> temp slot mapping. */
682 hashval_t
hash(temp_slot_address_entry * t)683 temp_address_hasher::hash (temp_slot_address_entry *t)
684 {
685 return t->hash;
686 }
687
688 /* Compare two address -> temp slot mapping entries. */
689 bool
equal(temp_slot_address_entry * t1,temp_slot_address_entry * t2)690 temp_address_hasher::equal (temp_slot_address_entry *t1,
691 temp_slot_address_entry *t2)
692 {
693 return exp_equiv_p (t1->address, t2->address, 0, true);
694 }
695
696 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
697 static void
insert_temp_slot_address(rtx address,struct temp_slot * temp_slot)698 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
699 {
700 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
701 t->address = address;
702 t->temp_slot = temp_slot;
703 t->hash = temp_slot_address_compute_hash (t);
704 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
705 }
706
707 /* Remove an address -> temp slot mapping entry if the temp slot is
708 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
709 int
remove_unused_temp_slot_addresses_1(temp_slot_address_entry ** slot,void *)710 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
711 {
712 const struct temp_slot_address_entry *t = *slot;
713 if (! t->temp_slot->in_use)
714 temp_slot_address_table->clear_slot (slot);
715 return 1;
716 }
717
718 /* Remove all mappings of addresses to unused temp slots. */
719 static void
remove_unused_temp_slot_addresses(void)720 remove_unused_temp_slot_addresses (void)
721 {
722 /* Use quicker clearing if there aren't any active temp slots. */
723 if (n_temp_slots_in_use)
724 temp_slot_address_table->traverse
725 <void *, remove_unused_temp_slot_addresses_1> (NULL);
726 else
727 temp_slot_address_table->empty ();
728 }
729
730 /* Find the temp slot corresponding to the object at address X. */
731
732 static struct temp_slot *
find_temp_slot_from_address(rtx x)733 find_temp_slot_from_address (rtx x)
734 {
735 struct temp_slot *p;
736 struct temp_slot_address_entry tmp, *t;
737
738 /* First try the easy way:
739 See if X exists in the address -> temp slot mapping. */
740 tmp.address = x;
741 tmp.temp_slot = NULL;
742 tmp.hash = temp_slot_address_compute_hash (&tmp);
743 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
744 if (t)
745 return t->temp_slot;
746
747 /* If we have a sum involving a register, see if it points to a temp
748 slot. */
749 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
750 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
751 return p;
752 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
753 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
754 return p;
755
756 /* Last resort: Address is a virtual stack var address. */
757 poly_int64 offset;
758 if (strip_offset (x, &offset) == virtual_stack_vars_rtx)
759 {
760 int i;
761 for (i = max_slot_level (); i >= 0; i--)
762 for (p = *temp_slots_at_level (i); p; p = p->next)
763 if (known_in_range_p (offset, p->base_offset, p->full_size))
764 return p;
765 }
766
767 return NULL;
768 }
769
770 /* Allocate a temporary stack slot and record it for possible later
771 reuse.
772
773 MODE is the machine mode to be given to the returned rtx.
774
775 SIZE is the size in units of the space required. We do no rounding here
776 since assign_stack_local will do any required rounding.
777
778 TYPE is the type that will be used for the stack slot. */
779
780 rtx
assign_stack_temp_for_type(machine_mode mode,poly_int64 size,tree type)781 assign_stack_temp_for_type (machine_mode mode, poly_int64 size, tree type)
782 {
783 unsigned int align;
784 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
785 rtx slot;
786
787 gcc_assert (known_size_p (size));
788
789 align = get_stack_local_alignment (type, mode);
790
791 /* Try to find an available, already-allocated temporary of the proper
792 mode which meets the size and alignment requirements. Choose the
793 smallest one with the closest alignment.
794
795 If assign_stack_temp is called outside of the tree->rtl expansion,
796 we cannot reuse the stack slots (that may still refer to
797 VIRTUAL_STACK_VARS_REGNUM). */
798 if (!virtuals_instantiated)
799 {
800 for (p = avail_temp_slots; p; p = p->next)
801 {
802 if (p->align >= align
803 && known_ge (p->size, size)
804 && GET_MODE (p->slot) == mode
805 && objects_must_conflict_p (p->type, type)
806 && (best_p == 0
807 || (known_eq (best_p->size, p->size)
808 ? best_p->align > p->align
809 : known_ge (best_p->size, p->size))))
810 {
811 if (p->align == align && known_eq (p->size, size))
812 {
813 selected = p;
814 cut_slot_from_list (selected, &avail_temp_slots);
815 best_p = 0;
816 break;
817 }
818 best_p = p;
819 }
820 }
821 }
822
823 /* Make our best, if any, the one to use. */
824 if (best_p)
825 {
826 selected = best_p;
827 cut_slot_from_list (selected, &avail_temp_slots);
828
829 /* If there are enough aligned bytes left over, make them into a new
830 temp_slot so that the extra bytes don't get wasted. Do this only
831 for BLKmode slots, so that we can be sure of the alignment. */
832 if (GET_MODE (best_p->slot) == BLKmode)
833 {
834 int alignment = best_p->align / BITS_PER_UNIT;
835 poly_int64 rounded_size = aligned_upper_bound (size, alignment);
836
837 if (known_ge (best_p->size - rounded_size, alignment))
838 {
839 p = ggc_alloc<temp_slot> ();
840 p->in_use = 0;
841 p->size = best_p->size - rounded_size;
842 p->base_offset = best_p->base_offset + rounded_size;
843 p->full_size = best_p->full_size - rounded_size;
844 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
845 p->align = best_p->align;
846 p->type = best_p->type;
847 insert_slot_to_list (p, &avail_temp_slots);
848
849 vec_safe_push (stack_slot_list, p->slot);
850
851 best_p->size = rounded_size;
852 best_p->full_size = rounded_size;
853 }
854 }
855 }
856
857 /* If we still didn't find one, make a new temporary. */
858 if (selected == 0)
859 {
860 poly_int64 frame_offset_old = frame_offset;
861
862 p = ggc_alloc<temp_slot> ();
863
864 /* We are passing an explicit alignment request to assign_stack_local.
865 One side effect of that is assign_stack_local will not round SIZE
866 to ensure the frame offset remains suitably aligned.
867
868 So for requests which depended on the rounding of SIZE, we go ahead
869 and round it now. We also make sure ALIGNMENT is at least
870 BIGGEST_ALIGNMENT. */
871 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
872 p->slot = assign_stack_local_1 (mode,
873 (mode == BLKmode
874 ? aligned_upper_bound (size,
875 (int) align
876 / BITS_PER_UNIT)
877 : size),
878 align, 0);
879
880 p->align = align;
881
882 /* The following slot size computation is necessary because we don't
883 know the actual size of the temporary slot until assign_stack_local
884 has performed all the frame alignment and size rounding for the
885 requested temporary. Note that extra space added for alignment
886 can be either above or below this stack slot depending on which
887 way the frame grows. We include the extra space if and only if it
888 is above this slot. */
889 if (FRAME_GROWS_DOWNWARD)
890 p->size = frame_offset_old - frame_offset;
891 else
892 p->size = size;
893
894 /* Now define the fields used by combine_temp_slots. */
895 if (FRAME_GROWS_DOWNWARD)
896 {
897 p->base_offset = frame_offset;
898 p->full_size = frame_offset_old - frame_offset;
899 }
900 else
901 {
902 p->base_offset = frame_offset_old;
903 p->full_size = frame_offset - frame_offset_old;
904 }
905
906 selected = p;
907 }
908
909 p = selected;
910 p->in_use = 1;
911 p->type = type;
912 p->level = temp_slot_level;
913 n_temp_slots_in_use++;
914
915 pp = temp_slots_at_level (p->level);
916 insert_slot_to_list (p, pp);
917 insert_temp_slot_address (XEXP (p->slot, 0), p);
918
919 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
920 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
921 vec_safe_push (stack_slot_list, slot);
922
923 /* If we know the alias set for the memory that will be used, use
924 it. If there's no TYPE, then we don't know anything about the
925 alias set for the memory. */
926 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
927 set_mem_align (slot, align);
928
929 /* If a type is specified, set the relevant flags. */
930 if (type != 0)
931 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
932 MEM_NOTRAP_P (slot) = 1;
933
934 return slot;
935 }
936
937 /* Allocate a temporary stack slot and record it for possible later
938 reuse. First two arguments are same as in preceding function. */
939
940 rtx
assign_stack_temp(machine_mode mode,poly_int64 size)941 assign_stack_temp (machine_mode mode, poly_int64 size)
942 {
943 return assign_stack_temp_for_type (mode, size, NULL_TREE);
944 }
945
946 /* Assign a temporary.
947 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
948 and so that should be used in error messages. In either case, we
949 allocate of the given type.
950 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
951 it is 0 if a register is OK.
952 DONT_PROMOTE is 1 if we should not promote values in register
953 to wider modes. */
954
955 rtx
assign_temp(tree type_or_decl,int memory_required,int dont_promote ATTRIBUTE_UNUSED)956 assign_temp (tree type_or_decl, int memory_required,
957 int dont_promote ATTRIBUTE_UNUSED)
958 {
959 tree type, decl;
960 machine_mode mode;
961 #ifdef PROMOTE_MODE
962 int unsignedp;
963 #endif
964
965 if (DECL_P (type_or_decl))
966 decl = type_or_decl, type = TREE_TYPE (decl);
967 else
968 decl = NULL, type = type_or_decl;
969
970 mode = TYPE_MODE (type);
971 #ifdef PROMOTE_MODE
972 unsignedp = TYPE_UNSIGNED (type);
973 #endif
974
975 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
976 end. See also create_tmp_var for the gimplification-time check. */
977 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
978
979 if (mode == BLKmode || memory_required)
980 {
981 HOST_WIDE_INT size = int_size_in_bytes (type);
982 rtx tmp;
983
984 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
985 problems with allocating the stack space. */
986 if (size == 0)
987 size = 1;
988
989 /* Unfortunately, we don't yet know how to allocate variable-sized
990 temporaries. However, sometimes we can find a fixed upper limit on
991 the size, so try that instead. */
992 else if (size == -1)
993 size = max_int_size_in_bytes (type);
994
995 /* The size of the temporary may be too large to fit into an integer. */
996 /* ??? Not sure this should happen except for user silliness, so limit
997 this to things that aren't compiler-generated temporaries. The
998 rest of the time we'll die in assign_stack_temp_for_type. */
999 if (decl && size == -1
1000 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1001 {
1002 error ("size of variable %q+D is too large", decl);
1003 size = 1;
1004 }
1005
1006 tmp = assign_stack_temp_for_type (mode, size, type);
1007 return tmp;
1008 }
1009
1010 #ifdef PROMOTE_MODE
1011 if (! dont_promote)
1012 mode = promote_mode (type, mode, &unsignedp);
1013 #endif
1014
1015 return gen_reg_rtx (mode);
1016 }
1017
1018 /* Combine temporary stack slots which are adjacent on the stack.
1019
1020 This allows for better use of already allocated stack space. This is only
1021 done for BLKmode slots because we can be sure that we won't have alignment
1022 problems in this case. */
1023
1024 static void
combine_temp_slots(void)1025 combine_temp_slots (void)
1026 {
1027 struct temp_slot *p, *q, *next, *next_q;
1028 int num_slots;
1029
1030 /* We can't combine slots, because the information about which slot
1031 is in which alias set will be lost. */
1032 if (flag_strict_aliasing)
1033 return;
1034
1035 /* If there are a lot of temp slots, don't do anything unless
1036 high levels of optimization. */
1037 if (! flag_expensive_optimizations)
1038 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1039 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1040 return;
1041
1042 for (p = avail_temp_slots; p; p = next)
1043 {
1044 int delete_p = 0;
1045
1046 next = p->next;
1047
1048 if (GET_MODE (p->slot) != BLKmode)
1049 continue;
1050
1051 for (q = p->next; q; q = next_q)
1052 {
1053 int delete_q = 0;
1054
1055 next_q = q->next;
1056
1057 if (GET_MODE (q->slot) != BLKmode)
1058 continue;
1059
1060 if (known_eq (p->base_offset + p->full_size, q->base_offset))
1061 {
1062 /* Q comes after P; combine Q into P. */
1063 p->size += q->size;
1064 p->full_size += q->full_size;
1065 delete_q = 1;
1066 }
1067 else if (known_eq (q->base_offset + q->full_size, p->base_offset))
1068 {
1069 /* P comes after Q; combine P into Q. */
1070 q->size += p->size;
1071 q->full_size += p->full_size;
1072 delete_p = 1;
1073 break;
1074 }
1075 if (delete_q)
1076 cut_slot_from_list (q, &avail_temp_slots);
1077 }
1078
1079 /* Either delete P or advance past it. */
1080 if (delete_p)
1081 cut_slot_from_list (p, &avail_temp_slots);
1082 }
1083 }
1084
1085 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1086 slot that previously was known by OLD_RTX. */
1087
1088 void
update_temp_slot_address(rtx old_rtx,rtx new_rtx)1089 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1090 {
1091 struct temp_slot *p;
1092
1093 if (rtx_equal_p (old_rtx, new_rtx))
1094 return;
1095
1096 p = find_temp_slot_from_address (old_rtx);
1097
1098 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1099 NEW_RTX is a register, see if one operand of the PLUS is a
1100 temporary location. If so, NEW_RTX points into it. Otherwise,
1101 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1102 in common between them. If so, try a recursive call on those
1103 values. */
1104 if (p == 0)
1105 {
1106 if (GET_CODE (old_rtx) != PLUS)
1107 return;
1108
1109 if (REG_P (new_rtx))
1110 {
1111 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1112 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1113 return;
1114 }
1115 else if (GET_CODE (new_rtx) != PLUS)
1116 return;
1117
1118 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1119 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1120 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1121 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1122 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1123 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1124 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1125 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1126
1127 return;
1128 }
1129
1130 /* Otherwise add an alias for the temp's address. */
1131 insert_temp_slot_address (new_rtx, p);
1132 }
1133
1134 /* If X could be a reference to a temporary slot, mark that slot as
1135 belonging to the to one level higher than the current level. If X
1136 matched one of our slots, just mark that one. Otherwise, we can't
1137 easily predict which it is, so upgrade all of them.
1138
1139 This is called when an ({...}) construct occurs and a statement
1140 returns a value in memory. */
1141
1142 void
preserve_temp_slots(rtx x)1143 preserve_temp_slots (rtx x)
1144 {
1145 struct temp_slot *p = 0, *next;
1146
1147 if (x == 0)
1148 return;
1149
1150 /* If X is a register that is being used as a pointer, see if we have
1151 a temporary slot we know it points to. */
1152 if (REG_P (x) && REG_POINTER (x))
1153 p = find_temp_slot_from_address (x);
1154
1155 /* If X is not in memory or is at a constant address, it cannot be in
1156 a temporary slot. */
1157 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1158 return;
1159
1160 /* First see if we can find a match. */
1161 if (p == 0)
1162 p = find_temp_slot_from_address (XEXP (x, 0));
1163
1164 if (p != 0)
1165 {
1166 if (p->level == temp_slot_level)
1167 move_slot_to_level (p, temp_slot_level - 1);
1168 return;
1169 }
1170
1171 /* Otherwise, preserve all non-kept slots at this level. */
1172 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1173 {
1174 next = p->next;
1175 move_slot_to_level (p, temp_slot_level - 1);
1176 }
1177 }
1178
1179 /* Free all temporaries used so far. This is normally called at the
1180 end of generating code for a statement. */
1181
1182 void
free_temp_slots(void)1183 free_temp_slots (void)
1184 {
1185 struct temp_slot *p, *next;
1186 bool some_available = false;
1187
1188 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1189 {
1190 next = p->next;
1191 make_slot_available (p);
1192 some_available = true;
1193 }
1194
1195 if (some_available)
1196 {
1197 remove_unused_temp_slot_addresses ();
1198 combine_temp_slots ();
1199 }
1200 }
1201
1202 /* Push deeper into the nesting level for stack temporaries. */
1203
1204 void
push_temp_slots(void)1205 push_temp_slots (void)
1206 {
1207 temp_slot_level++;
1208 }
1209
1210 /* Pop a temporary nesting level. All slots in use in the current level
1211 are freed. */
1212
1213 void
pop_temp_slots(void)1214 pop_temp_slots (void)
1215 {
1216 free_temp_slots ();
1217 temp_slot_level--;
1218 }
1219
1220 /* Initialize temporary slots. */
1221
1222 void
init_temp_slots(void)1223 init_temp_slots (void)
1224 {
1225 /* We have not allocated any temporaries yet. */
1226 avail_temp_slots = 0;
1227 vec_alloc (used_temp_slots, 0);
1228 temp_slot_level = 0;
1229 n_temp_slots_in_use = 0;
1230
1231 /* Set up the table to map addresses to temp slots. */
1232 if (! temp_slot_address_table)
1233 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1234 else
1235 temp_slot_address_table->empty ();
1236 }
1237
1238 /* Functions and data structures to keep track of the values hard regs
1239 had at the start of the function. */
1240
1241 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1242 and has_hard_reg_initial_val.. */
1243 struct GTY(()) initial_value_pair {
1244 rtx hard_reg;
1245 rtx pseudo;
1246 };
1247 /* ??? This could be a VEC but there is currently no way to define an
1248 opaque VEC type. This could be worked around by defining struct
1249 initial_value_pair in function.h. */
1250 struct GTY(()) initial_value_struct {
1251 int num_entries;
1252 int max_entries;
1253 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1254 };
1255
1256 /* If a pseudo represents an initial hard reg (or expression), return
1257 it, else return NULL_RTX. */
1258
1259 rtx
get_hard_reg_initial_reg(rtx reg)1260 get_hard_reg_initial_reg (rtx reg)
1261 {
1262 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1263 int i;
1264
1265 if (ivs == 0)
1266 return NULL_RTX;
1267
1268 for (i = 0; i < ivs->num_entries; i++)
1269 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1270 return ivs->entries[i].hard_reg;
1271
1272 return NULL_RTX;
1273 }
1274
1275 /* Make sure that there's a pseudo register of mode MODE that stores the
1276 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1277
1278 rtx
get_hard_reg_initial_val(machine_mode mode,unsigned int regno)1279 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1280 {
1281 struct initial_value_struct *ivs;
1282 rtx rv;
1283
1284 rv = has_hard_reg_initial_val (mode, regno);
1285 if (rv)
1286 return rv;
1287
1288 ivs = crtl->hard_reg_initial_vals;
1289 if (ivs == 0)
1290 {
1291 ivs = ggc_alloc<initial_value_struct> ();
1292 ivs->num_entries = 0;
1293 ivs->max_entries = 5;
1294 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1295 crtl->hard_reg_initial_vals = ivs;
1296 }
1297
1298 if (ivs->num_entries >= ivs->max_entries)
1299 {
1300 ivs->max_entries += 5;
1301 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1302 ivs->max_entries);
1303 }
1304
1305 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1306 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1307
1308 return ivs->entries[ivs->num_entries++].pseudo;
1309 }
1310
1311 /* See if get_hard_reg_initial_val has been used to create a pseudo
1312 for the initial value of hard register REGNO in mode MODE. Return
1313 the associated pseudo if so, otherwise return NULL. */
1314
1315 rtx
has_hard_reg_initial_val(machine_mode mode,unsigned int regno)1316 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1317 {
1318 struct initial_value_struct *ivs;
1319 int i;
1320
1321 ivs = crtl->hard_reg_initial_vals;
1322 if (ivs != 0)
1323 for (i = 0; i < ivs->num_entries; i++)
1324 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1325 && REGNO (ivs->entries[i].hard_reg) == regno)
1326 return ivs->entries[i].pseudo;
1327
1328 return NULL_RTX;
1329 }
1330
1331 unsigned int
emit_initial_value_sets(void)1332 emit_initial_value_sets (void)
1333 {
1334 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1335 int i;
1336 rtx_insn *seq;
1337
1338 if (ivs == 0)
1339 return 0;
1340
1341 start_sequence ();
1342 for (i = 0; i < ivs->num_entries; i++)
1343 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1344 seq = get_insns ();
1345 end_sequence ();
1346
1347 emit_insn_at_entry (seq);
1348 return 0;
1349 }
1350
1351 /* Return the hardreg-pseudoreg initial values pair entry I and
1352 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1353 bool
initial_value_entry(int i,rtx * hreg,rtx * preg)1354 initial_value_entry (int i, rtx *hreg, rtx *preg)
1355 {
1356 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1357 if (!ivs || i >= ivs->num_entries)
1358 return false;
1359
1360 *hreg = ivs->entries[i].hard_reg;
1361 *preg = ivs->entries[i].pseudo;
1362 return true;
1363 }
1364
1365 /* These routines are responsible for converting virtual register references
1366 to the actual hard register references once RTL generation is complete.
1367
1368 The following four variables are used for communication between the
1369 routines. They contain the offsets of the virtual registers from their
1370 respective hard registers. */
1371
1372 static poly_int64 in_arg_offset;
1373 static poly_int64 var_offset;
1374 static poly_int64 dynamic_offset;
1375 static poly_int64 out_arg_offset;
1376 static poly_int64 cfa_offset;
1377
1378 /* In most machines, the stack pointer register is equivalent to the bottom
1379 of the stack. */
1380
1381 #ifndef STACK_POINTER_OFFSET
1382 #define STACK_POINTER_OFFSET 0
1383 #endif
1384
1385 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1386 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1387 #endif
1388
1389 /* If not defined, pick an appropriate default for the offset of dynamically
1390 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1391 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1392
1393 #ifndef STACK_DYNAMIC_OFFSET
1394
1395 /* The bottom of the stack points to the actual arguments. If
1396 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1397 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1398 stack space for register parameters is not pushed by the caller, but
1399 rather part of the fixed stack areas and hence not included in
1400 `crtl->outgoing_args_size'. Nevertheless, we must allow
1401 for it when allocating stack dynamic objects. */
1402
1403 #ifdef INCOMING_REG_PARM_STACK_SPACE
1404 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1405 ((ACCUMULATE_OUTGOING_ARGS \
1406 ? (crtl->outgoing_args_size \
1407 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1408 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1409 : 0) + (STACK_POINTER_OFFSET))
1410 #else
1411 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1412 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : poly_int64 (0)) \
1413 + (STACK_POINTER_OFFSET))
1414 #endif
1415 #endif
1416
1417
1418 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1419 is a virtual register, return the equivalent hard register and set the
1420 offset indirectly through the pointer. Otherwise, return 0. */
1421
1422 static rtx
instantiate_new_reg(rtx x,poly_int64_pod * poffset)1423 instantiate_new_reg (rtx x, poly_int64_pod *poffset)
1424 {
1425 rtx new_rtx;
1426 poly_int64 offset;
1427
1428 if (x == virtual_incoming_args_rtx)
1429 {
1430 if (stack_realign_drap)
1431 {
1432 /* Replace virtual_incoming_args_rtx with internal arg
1433 pointer if DRAP is used to realign stack. */
1434 new_rtx = crtl->args.internal_arg_pointer;
1435 offset = 0;
1436 }
1437 else
1438 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1439 }
1440 else if (x == virtual_stack_vars_rtx)
1441 new_rtx = frame_pointer_rtx, offset = var_offset;
1442 else if (x == virtual_stack_dynamic_rtx)
1443 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1444 else if (x == virtual_outgoing_args_rtx)
1445 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1446 else if (x == virtual_cfa_rtx)
1447 {
1448 #ifdef FRAME_POINTER_CFA_OFFSET
1449 new_rtx = frame_pointer_rtx;
1450 #else
1451 new_rtx = arg_pointer_rtx;
1452 #endif
1453 offset = cfa_offset;
1454 }
1455 else if (x == virtual_preferred_stack_boundary_rtx)
1456 {
1457 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1458 offset = 0;
1459 }
1460 else
1461 return NULL_RTX;
1462
1463 *poffset = offset;
1464 return new_rtx;
1465 }
1466
1467 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1468 registers present inside of *LOC. The expression is simplified,
1469 as much as possible, but is not to be considered "valid" in any sense
1470 implied by the target. Return true if any change is made. */
1471
1472 static bool
instantiate_virtual_regs_in_rtx(rtx * loc)1473 instantiate_virtual_regs_in_rtx (rtx *loc)
1474 {
1475 if (!*loc)
1476 return false;
1477 bool changed = false;
1478 subrtx_ptr_iterator::array_type array;
1479 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1480 {
1481 rtx *loc = *iter;
1482 if (rtx x = *loc)
1483 {
1484 rtx new_rtx;
1485 poly_int64 offset;
1486 switch (GET_CODE (x))
1487 {
1488 case REG:
1489 new_rtx = instantiate_new_reg (x, &offset);
1490 if (new_rtx)
1491 {
1492 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1493 changed = true;
1494 }
1495 iter.skip_subrtxes ();
1496 break;
1497
1498 case PLUS:
1499 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1500 if (new_rtx)
1501 {
1502 XEXP (x, 0) = new_rtx;
1503 *loc = plus_constant (GET_MODE (x), x, offset, true);
1504 changed = true;
1505 iter.skip_subrtxes ();
1506 break;
1507 }
1508
1509 /* FIXME -- from old code */
1510 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1511 we can commute the PLUS and SUBREG because pointers into the
1512 frame are well-behaved. */
1513 break;
1514
1515 default:
1516 break;
1517 }
1518 }
1519 }
1520 return changed;
1521 }
1522
1523 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1524 matches the predicate for insn CODE operand OPERAND. */
1525
1526 static int
safe_insn_predicate(int code,int operand,rtx x)1527 safe_insn_predicate (int code, int operand, rtx x)
1528 {
1529 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1530 }
1531
1532 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1533 registers present inside of insn. The result will be a valid insn. */
1534
1535 static void
instantiate_virtual_regs_in_insn(rtx_insn * insn)1536 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1537 {
1538 poly_int64 offset;
1539 int insn_code, i;
1540 bool any_change = false;
1541 rtx set, new_rtx, x;
1542 rtx_insn *seq;
1543
1544 /* There are some special cases to be handled first. */
1545 set = single_set (insn);
1546 if (set)
1547 {
1548 /* We're allowed to assign to a virtual register. This is interpreted
1549 to mean that the underlying register gets assigned the inverse
1550 transformation. This is used, for example, in the handling of
1551 non-local gotos. */
1552 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1553 if (new_rtx)
1554 {
1555 start_sequence ();
1556
1557 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1558 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1559 gen_int_mode (-offset, GET_MODE (new_rtx)));
1560 x = force_operand (x, new_rtx);
1561 if (x != new_rtx)
1562 emit_move_insn (new_rtx, x);
1563
1564 seq = get_insns ();
1565 end_sequence ();
1566
1567 emit_insn_before (seq, insn);
1568 delete_insn (insn);
1569 return;
1570 }
1571
1572 /* Handle a straight copy from a virtual register by generating a
1573 new add insn. The difference between this and falling through
1574 to the generic case is avoiding a new pseudo and eliminating a
1575 move insn in the initial rtl stream. */
1576 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1577 if (new_rtx
1578 && maybe_ne (offset, 0)
1579 && REG_P (SET_DEST (set))
1580 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1581 {
1582 start_sequence ();
1583
1584 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1585 gen_int_mode (offset,
1586 GET_MODE (SET_DEST (set))),
1587 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1588 if (x != SET_DEST (set))
1589 emit_move_insn (SET_DEST (set), x);
1590
1591 seq = get_insns ();
1592 end_sequence ();
1593
1594 emit_insn_before (seq, insn);
1595 delete_insn (insn);
1596 return;
1597 }
1598
1599 extract_insn (insn);
1600 insn_code = INSN_CODE (insn);
1601
1602 /* Handle a plus involving a virtual register by determining if the
1603 operands remain valid if they're modified in place. */
1604 poly_int64 delta;
1605 if (GET_CODE (SET_SRC (set)) == PLUS
1606 && recog_data.n_operands >= 3
1607 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1608 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1609 && poly_int_rtx_p (recog_data.operand[2], &delta)
1610 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1611 {
1612 offset += delta;
1613
1614 /* If the sum is zero, then replace with a plain move. */
1615 if (known_eq (offset, 0)
1616 && REG_P (SET_DEST (set))
1617 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1618 {
1619 start_sequence ();
1620 emit_move_insn (SET_DEST (set), new_rtx);
1621 seq = get_insns ();
1622 end_sequence ();
1623
1624 emit_insn_before (seq, insn);
1625 delete_insn (insn);
1626 return;
1627 }
1628
1629 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1630
1631 /* Using validate_change and apply_change_group here leaves
1632 recog_data in an invalid state. Since we know exactly what
1633 we want to check, do those two by hand. */
1634 if (safe_insn_predicate (insn_code, 1, new_rtx)
1635 && safe_insn_predicate (insn_code, 2, x))
1636 {
1637 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1638 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1639 any_change = true;
1640
1641 /* Fall through into the regular operand fixup loop in
1642 order to take care of operands other than 1 and 2. */
1643 }
1644 }
1645 }
1646 else
1647 {
1648 extract_insn (insn);
1649 insn_code = INSN_CODE (insn);
1650 }
1651
1652 /* In the general case, we expect virtual registers to appear only in
1653 operands, and then only as either bare registers or inside memories. */
1654 for (i = 0; i < recog_data.n_operands; ++i)
1655 {
1656 x = recog_data.operand[i];
1657 switch (GET_CODE (x))
1658 {
1659 case MEM:
1660 {
1661 rtx addr = XEXP (x, 0);
1662
1663 if (!instantiate_virtual_regs_in_rtx (&addr))
1664 continue;
1665
1666 start_sequence ();
1667 x = replace_equiv_address (x, addr, true);
1668 /* It may happen that the address with the virtual reg
1669 was valid (e.g. based on the virtual stack reg, which might
1670 be acceptable to the predicates with all offsets), whereas
1671 the address now isn't anymore, for instance when the address
1672 is still offsetted, but the base reg isn't virtual-stack-reg
1673 anymore. Below we would do a force_reg on the whole operand,
1674 but this insn might actually only accept memory. Hence,
1675 before doing that last resort, try to reload the address into
1676 a register, so this operand stays a MEM. */
1677 if (!safe_insn_predicate (insn_code, i, x))
1678 {
1679 addr = force_reg (GET_MODE (addr), addr);
1680 x = replace_equiv_address (x, addr, true);
1681 }
1682 seq = get_insns ();
1683 end_sequence ();
1684 if (seq)
1685 emit_insn_before (seq, insn);
1686 }
1687 break;
1688
1689 case REG:
1690 new_rtx = instantiate_new_reg (x, &offset);
1691 if (new_rtx == NULL)
1692 continue;
1693 if (known_eq (offset, 0))
1694 x = new_rtx;
1695 else
1696 {
1697 start_sequence ();
1698
1699 /* Careful, special mode predicates may have stuff in
1700 insn_data[insn_code].operand[i].mode that isn't useful
1701 to us for computing a new value. */
1702 /* ??? Recognize address_operand and/or "p" constraints
1703 to see if (plus new offset) is a valid before we put
1704 this through expand_simple_binop. */
1705 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1706 gen_int_mode (offset, GET_MODE (x)),
1707 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1708 seq = get_insns ();
1709 end_sequence ();
1710 emit_insn_before (seq, insn);
1711 }
1712 break;
1713
1714 case SUBREG:
1715 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1716 if (new_rtx == NULL)
1717 continue;
1718 if (maybe_ne (offset, 0))
1719 {
1720 start_sequence ();
1721 new_rtx = expand_simple_binop
1722 (GET_MODE (new_rtx), PLUS, new_rtx,
1723 gen_int_mode (offset, GET_MODE (new_rtx)),
1724 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1725 seq = get_insns ();
1726 end_sequence ();
1727 emit_insn_before (seq, insn);
1728 }
1729 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1730 GET_MODE (new_rtx), SUBREG_BYTE (x));
1731 gcc_assert (x);
1732 break;
1733
1734 default:
1735 continue;
1736 }
1737
1738 /* At this point, X contains the new value for the operand.
1739 Validate the new value vs the insn predicate. Note that
1740 asm insns will have insn_code -1 here. */
1741 if (!safe_insn_predicate (insn_code, i, x))
1742 {
1743 start_sequence ();
1744 if (REG_P (x))
1745 {
1746 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1747 x = copy_to_reg (x);
1748 }
1749 else
1750 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1751 seq = get_insns ();
1752 end_sequence ();
1753 if (seq)
1754 emit_insn_before (seq, insn);
1755 }
1756
1757 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1758 any_change = true;
1759 }
1760
1761 if (any_change)
1762 {
1763 /* Propagate operand changes into the duplicates. */
1764 for (i = 0; i < recog_data.n_dups; ++i)
1765 *recog_data.dup_loc[i]
1766 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1767
1768 /* Force re-recognition of the instruction for validation. */
1769 INSN_CODE (insn) = -1;
1770 }
1771
1772 if (asm_noperands (PATTERN (insn)) >= 0)
1773 {
1774 if (!check_asm_operands (PATTERN (insn)))
1775 {
1776 error_for_asm (insn, "impossible constraint in %<asm%>");
1777 /* For asm goto, instead of fixing up all the edges
1778 just clear the template and clear input operands
1779 (asm goto doesn't have any output operands). */
1780 if (JUMP_P (insn))
1781 {
1782 rtx asm_op = extract_asm_operands (PATTERN (insn));
1783 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1784 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1785 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1786 }
1787 else
1788 delete_insn (insn);
1789 }
1790 }
1791 else
1792 {
1793 if (recog_memoized (insn) < 0)
1794 fatal_insn_not_found (insn);
1795 }
1796 }
1797
1798 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1799 do any instantiation required. */
1800
1801 void
instantiate_decl_rtl(rtx x)1802 instantiate_decl_rtl (rtx x)
1803 {
1804 rtx addr;
1805
1806 if (x == 0)
1807 return;
1808
1809 /* If this is a CONCAT, recurse for the pieces. */
1810 if (GET_CODE (x) == CONCAT)
1811 {
1812 instantiate_decl_rtl (XEXP (x, 0));
1813 instantiate_decl_rtl (XEXP (x, 1));
1814 return;
1815 }
1816
1817 /* If this is not a MEM, no need to do anything. Similarly if the
1818 address is a constant or a register that is not a virtual register. */
1819 if (!MEM_P (x))
1820 return;
1821
1822 addr = XEXP (x, 0);
1823 if (CONSTANT_P (addr)
1824 || (REG_P (addr)
1825 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1826 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1827 return;
1828
1829 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1830 }
1831
1832 /* Helper for instantiate_decls called via walk_tree: Process all decls
1833 in the given DECL_VALUE_EXPR. */
1834
1835 static tree
instantiate_expr(tree * tp,int * walk_subtrees,void * data ATTRIBUTE_UNUSED)1836 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1837 {
1838 tree t = *tp;
1839 if (! EXPR_P (t))
1840 {
1841 *walk_subtrees = 0;
1842 if (DECL_P (t))
1843 {
1844 if (DECL_RTL_SET_P (t))
1845 instantiate_decl_rtl (DECL_RTL (t));
1846 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1847 && DECL_INCOMING_RTL (t))
1848 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1849 if ((VAR_P (t) || TREE_CODE (t) == RESULT_DECL)
1850 && DECL_HAS_VALUE_EXPR_P (t))
1851 {
1852 tree v = DECL_VALUE_EXPR (t);
1853 walk_tree (&v, instantiate_expr, NULL, NULL);
1854 }
1855 }
1856 }
1857 return NULL;
1858 }
1859
1860 /* Subroutine of instantiate_decls: Process all decls in the given
1861 BLOCK node and all its subblocks. */
1862
1863 static void
instantiate_decls_1(tree let)1864 instantiate_decls_1 (tree let)
1865 {
1866 tree t;
1867
1868 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1869 {
1870 if (DECL_RTL_SET_P (t))
1871 instantiate_decl_rtl (DECL_RTL (t));
1872 if (VAR_P (t) && DECL_HAS_VALUE_EXPR_P (t))
1873 {
1874 tree v = DECL_VALUE_EXPR (t);
1875 walk_tree (&v, instantiate_expr, NULL, NULL);
1876 }
1877 }
1878
1879 /* Process all subblocks. */
1880 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1881 instantiate_decls_1 (t);
1882 }
1883
1884 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1885 all virtual registers in their DECL_RTL's. */
1886
1887 static void
instantiate_decls(tree fndecl)1888 instantiate_decls (tree fndecl)
1889 {
1890 tree decl;
1891 unsigned ix;
1892
1893 /* Process all parameters of the function. */
1894 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1895 {
1896 instantiate_decl_rtl (DECL_RTL (decl));
1897 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1898 if (DECL_HAS_VALUE_EXPR_P (decl))
1899 {
1900 tree v = DECL_VALUE_EXPR (decl);
1901 walk_tree (&v, instantiate_expr, NULL, NULL);
1902 }
1903 }
1904
1905 if ((decl = DECL_RESULT (fndecl))
1906 && TREE_CODE (decl) == RESULT_DECL)
1907 {
1908 if (DECL_RTL_SET_P (decl))
1909 instantiate_decl_rtl (DECL_RTL (decl));
1910 if (DECL_HAS_VALUE_EXPR_P (decl))
1911 {
1912 tree v = DECL_VALUE_EXPR (decl);
1913 walk_tree (&v, instantiate_expr, NULL, NULL);
1914 }
1915 }
1916
1917 /* Process the saved static chain if it exists. */
1918 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1919 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1920 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1921
1922 /* Now process all variables defined in the function or its subblocks. */
1923 if (DECL_INITIAL (fndecl))
1924 instantiate_decls_1 (DECL_INITIAL (fndecl));
1925
1926 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1927 if (DECL_RTL_SET_P (decl))
1928 instantiate_decl_rtl (DECL_RTL (decl));
1929 vec_free (cfun->local_decls);
1930 }
1931
1932 /* Pass through the INSNS of function FNDECL and convert virtual register
1933 references to hard register references. */
1934
1935 static unsigned int
instantiate_virtual_regs(void)1936 instantiate_virtual_regs (void)
1937 {
1938 rtx_insn *insn;
1939
1940 /* Compute the offsets to use for this function. */
1941 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1942 var_offset = targetm.starting_frame_offset ();
1943 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1944 out_arg_offset = STACK_POINTER_OFFSET;
1945 #ifdef FRAME_POINTER_CFA_OFFSET
1946 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1947 #else
1948 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1949 #endif
1950
1951 /* Initialize recognition, indicating that volatile is OK. */
1952 init_recog ();
1953
1954 /* Scan through all the insns, instantiating every virtual register still
1955 present. */
1956 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1957 if (INSN_P (insn))
1958 {
1959 /* These patterns in the instruction stream can never be recognized.
1960 Fortunately, they shouldn't contain virtual registers either. */
1961 if (GET_CODE (PATTERN (insn)) == USE
1962 || GET_CODE (PATTERN (insn)) == CLOBBER
1963 || GET_CODE (PATTERN (insn)) == ASM_INPUT
1964 || DEBUG_MARKER_INSN_P (insn))
1965 continue;
1966 else if (DEBUG_BIND_INSN_P (insn))
1967 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn));
1968 else
1969 instantiate_virtual_regs_in_insn (insn);
1970
1971 if (insn->deleted ())
1972 continue;
1973
1974 instantiate_virtual_regs_in_rtx (®_NOTES (insn));
1975
1976 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1977 if (CALL_P (insn))
1978 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1979 }
1980
1981 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1982 instantiate_decls (current_function_decl);
1983
1984 targetm.instantiate_decls ();
1985
1986 /* Indicate that, from now on, assign_stack_local should use
1987 frame_pointer_rtx. */
1988 virtuals_instantiated = 1;
1989
1990 return 0;
1991 }
1992
1993 namespace {
1994
1995 const pass_data pass_data_instantiate_virtual_regs =
1996 {
1997 RTL_PASS, /* type */
1998 "vregs", /* name */
1999 OPTGROUP_NONE, /* optinfo_flags */
2000 TV_NONE, /* tv_id */
2001 0, /* properties_required */
2002 0, /* properties_provided */
2003 0, /* properties_destroyed */
2004 0, /* todo_flags_start */
2005 0, /* todo_flags_finish */
2006 };
2007
2008 class pass_instantiate_virtual_regs : public rtl_opt_pass
2009 {
2010 public:
pass_instantiate_virtual_regs(gcc::context * ctxt)2011 pass_instantiate_virtual_regs (gcc::context *ctxt)
2012 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2013 {}
2014
2015 /* opt_pass methods: */
execute(function *)2016 virtual unsigned int execute (function *)
2017 {
2018 return instantiate_virtual_regs ();
2019 }
2020
2021 }; // class pass_instantiate_virtual_regs
2022
2023 } // anon namespace
2024
2025 rtl_opt_pass *
make_pass_instantiate_virtual_regs(gcc::context * ctxt)2026 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2027 {
2028 return new pass_instantiate_virtual_regs (ctxt);
2029 }
2030
2031
2032 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2033 This means a type for which function calls must pass an address to the
2034 function or get an address back from the function.
2035 EXP may be a type node or an expression (whose type is tested). */
2036
2037 int
aggregate_value_p(const_tree exp,const_tree fntype)2038 aggregate_value_p (const_tree exp, const_tree fntype)
2039 {
2040 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2041 int i, regno, nregs;
2042 rtx reg;
2043
2044 if (fntype)
2045 switch (TREE_CODE (fntype))
2046 {
2047 case CALL_EXPR:
2048 {
2049 tree fndecl = get_callee_fndecl (fntype);
2050 if (fndecl)
2051 fntype = TREE_TYPE (fndecl);
2052 else if (CALL_EXPR_FN (fntype))
2053 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2054 else
2055 /* For internal functions, assume nothing needs to be
2056 returned in memory. */
2057 return 0;
2058 }
2059 break;
2060 case FUNCTION_DECL:
2061 fntype = TREE_TYPE (fntype);
2062 break;
2063 case FUNCTION_TYPE:
2064 case METHOD_TYPE:
2065 break;
2066 case IDENTIFIER_NODE:
2067 fntype = NULL_TREE;
2068 break;
2069 default:
2070 /* We don't expect other tree types here. */
2071 gcc_unreachable ();
2072 }
2073
2074 if (VOID_TYPE_P (type))
2075 return 0;
2076
2077 /* If a record should be passed the same as its first (and only) member
2078 don't pass it as an aggregate. */
2079 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2080 return aggregate_value_p (first_field (type), fntype);
2081
2082 /* If the front end has decided that this needs to be passed by
2083 reference, do so. */
2084 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2085 && DECL_BY_REFERENCE (exp))
2086 return 1;
2087
2088 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2089 if (fntype && TREE_ADDRESSABLE (fntype))
2090 return 1;
2091
2092 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2093 and thus can't be returned in registers. */
2094 if (TREE_ADDRESSABLE (type))
2095 return 1;
2096
2097 if (TYPE_EMPTY_P (type))
2098 return 0;
2099
2100 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2101 return 1;
2102
2103 if (targetm.calls.return_in_memory (type, fntype))
2104 return 1;
2105
2106 /* Make sure we have suitable call-clobbered regs to return
2107 the value in; if not, we must return it in memory. */
2108 reg = hard_function_value (type, 0, fntype, 0);
2109
2110 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2111 it is OK. */
2112 if (!REG_P (reg))
2113 return 0;
2114
2115 regno = REGNO (reg);
2116 nregs = hard_regno_nregs (regno, TYPE_MODE (type));
2117 for (i = 0; i < nregs; i++)
2118 if (! call_used_regs[regno + i])
2119 return 1;
2120
2121 return 0;
2122 }
2123
2124 /* Return true if we should assign DECL a pseudo register; false if it
2125 should live on the local stack. */
2126
2127 bool
use_register_for_decl(const_tree decl)2128 use_register_for_decl (const_tree decl)
2129 {
2130 if (TREE_CODE (decl) == SSA_NAME)
2131 {
2132 /* We often try to use the SSA_NAME, instead of its underlying
2133 decl, to get type information and guide decisions, to avoid
2134 differences of behavior between anonymous and named
2135 variables, but in this one case we have to go for the actual
2136 variable if there is one. The main reason is that, at least
2137 at -O0, we want to place user variables on the stack, but we
2138 don't mind using pseudos for anonymous or ignored temps.
2139 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2140 should go in pseudos, whereas their corresponding variables
2141 might have to go on the stack. So, disregarding the decl
2142 here would negatively impact debug info at -O0, enable
2143 coalescing between SSA_NAMEs that ought to get different
2144 stack/pseudo assignments, and get the incoming argument
2145 processing thoroughly confused by PARM_DECLs expected to live
2146 in stack slots but assigned to pseudos. */
2147 if (!SSA_NAME_VAR (decl))
2148 return TYPE_MODE (TREE_TYPE (decl)) != BLKmode
2149 && !(flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)));
2150
2151 decl = SSA_NAME_VAR (decl);
2152 }
2153
2154 /* Honor volatile. */
2155 if (TREE_SIDE_EFFECTS (decl))
2156 return false;
2157
2158 /* Honor addressability. */
2159 if (TREE_ADDRESSABLE (decl))
2160 return false;
2161
2162 /* RESULT_DECLs are a bit special in that they're assigned without
2163 regard to use_register_for_decl, but we generally only store in
2164 them. If we coalesce their SSA NAMEs, we'd better return a
2165 result that matches the assignment in expand_function_start. */
2166 if (TREE_CODE (decl) == RESULT_DECL)
2167 {
2168 /* If it's not an aggregate, we're going to use a REG or a
2169 PARALLEL containing a REG. */
2170 if (!aggregate_value_p (decl, current_function_decl))
2171 return true;
2172
2173 /* If expand_function_start determines the return value, we'll
2174 use MEM if it's not by reference. */
2175 if (cfun->returns_pcc_struct
2176 || (targetm.calls.struct_value_rtx
2177 (TREE_TYPE (current_function_decl), 1)))
2178 return DECL_BY_REFERENCE (decl);
2179
2180 /* Otherwise, we're taking an extra all.function_result_decl
2181 argument. It's set up in assign_parms_augmented_arg_list,
2182 under the (negated) conditions above, and then it's used to
2183 set up the RESULT_DECL rtl in assign_params, after looping
2184 over all parameters. Now, if the RESULT_DECL is not by
2185 reference, we'll use a MEM either way. */
2186 if (!DECL_BY_REFERENCE (decl))
2187 return false;
2188
2189 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2190 the function_result_decl's assignment. Since it's a pointer,
2191 we can short-circuit a number of the tests below, and we must
2192 duplicat e them because we don't have the
2193 function_result_decl to test. */
2194 if (!targetm.calls.allocate_stack_slots_for_args ())
2195 return true;
2196 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2197 if (optimize)
2198 return true;
2199 /* We don't set DECL_REGISTER for the function_result_decl. */
2200 return false;
2201 }
2202
2203 /* Decl is implicitly addressible by bound stores and loads
2204 if it is an aggregate holding bounds. */
2205 if (chkp_function_instrumented_p (current_function_decl)
2206 && TREE_TYPE (decl)
2207 && !BOUNDED_P (decl)
2208 && chkp_type_has_pointer (TREE_TYPE (decl)))
2209 return false;
2210
2211 /* Only register-like things go in registers. */
2212 if (DECL_MODE (decl) == BLKmode)
2213 return false;
2214
2215 /* If -ffloat-store specified, don't put explicit float variables
2216 into registers. */
2217 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2218 propagates values across these stores, and it probably shouldn't. */
2219 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2220 return false;
2221
2222 if (!targetm.calls.allocate_stack_slots_for_args ())
2223 return true;
2224
2225 /* If we're not interested in tracking debugging information for
2226 this decl, then we can certainly put it in a register. */
2227 if (DECL_IGNORED_P (decl))
2228 return true;
2229
2230 if (optimize)
2231 return true;
2232
2233 if (!DECL_REGISTER (decl))
2234 return false;
2235
2236 /* When not optimizing, disregard register keyword for types that
2237 could have methods, otherwise the methods won't be callable from
2238 the debugger. */
2239 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl)))
2240 return false;
2241
2242 return true;
2243 }
2244
2245 /* Structures to communicate between the subroutines of assign_parms.
2246 The first holds data persistent across all parameters, the second
2247 is cleared out for each parameter. */
2248
2249 struct assign_parm_data_all
2250 {
2251 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2252 should become a job of the target or otherwise encapsulated. */
2253 CUMULATIVE_ARGS args_so_far_v;
2254 cumulative_args_t args_so_far;
2255 struct args_size stack_args_size;
2256 tree function_result_decl;
2257 tree orig_fnargs;
2258 rtx_insn *first_conversion_insn;
2259 rtx_insn *last_conversion_insn;
2260 HOST_WIDE_INT pretend_args_size;
2261 HOST_WIDE_INT extra_pretend_bytes;
2262 int reg_parm_stack_space;
2263 };
2264
2265 struct assign_parm_data_one
2266 {
2267 tree nominal_type;
2268 tree passed_type;
2269 rtx entry_parm;
2270 rtx stack_parm;
2271 machine_mode nominal_mode;
2272 machine_mode passed_mode;
2273 machine_mode promoted_mode;
2274 struct locate_and_pad_arg_data locate;
2275 int partial;
2276 BOOL_BITFIELD named_arg : 1;
2277 BOOL_BITFIELD passed_pointer : 1;
2278 BOOL_BITFIELD on_stack : 1;
2279 BOOL_BITFIELD loaded_in_reg : 1;
2280 };
2281
2282 struct bounds_parm_data
2283 {
2284 assign_parm_data_one parm_data;
2285 tree bounds_parm;
2286 tree ptr_parm;
2287 rtx ptr_entry;
2288 int bound_no;
2289 };
2290
2291 /* A subroutine of assign_parms. Initialize ALL. */
2292
2293 static void
assign_parms_initialize_all(struct assign_parm_data_all * all)2294 assign_parms_initialize_all (struct assign_parm_data_all *all)
2295 {
2296 tree fntype ATTRIBUTE_UNUSED;
2297
2298 memset (all, 0, sizeof (*all));
2299
2300 fntype = TREE_TYPE (current_function_decl);
2301
2302 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2303 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2304 #else
2305 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2306 current_function_decl, -1);
2307 #endif
2308 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2309
2310 #ifdef INCOMING_REG_PARM_STACK_SPACE
2311 all->reg_parm_stack_space
2312 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2313 #endif
2314 }
2315
2316 /* If ARGS contains entries with complex types, split the entry into two
2317 entries of the component type. Return a new list of substitutions are
2318 needed, else the old list. */
2319
2320 static void
split_complex_args(vec<tree> * args)2321 split_complex_args (vec<tree> *args)
2322 {
2323 unsigned i;
2324 tree p;
2325
2326 FOR_EACH_VEC_ELT (*args, i, p)
2327 {
2328 tree type = TREE_TYPE (p);
2329 if (TREE_CODE (type) == COMPLEX_TYPE
2330 && targetm.calls.split_complex_arg (type))
2331 {
2332 tree decl;
2333 tree subtype = TREE_TYPE (type);
2334 bool addressable = TREE_ADDRESSABLE (p);
2335
2336 /* Rewrite the PARM_DECL's type with its component. */
2337 p = copy_node (p);
2338 TREE_TYPE (p) = subtype;
2339 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2340 SET_DECL_MODE (p, VOIDmode);
2341 DECL_SIZE (p) = NULL;
2342 DECL_SIZE_UNIT (p) = NULL;
2343 /* If this arg must go in memory, put it in a pseudo here.
2344 We can't allow it to go in memory as per normal parms,
2345 because the usual place might not have the imag part
2346 adjacent to the real part. */
2347 DECL_ARTIFICIAL (p) = addressable;
2348 DECL_IGNORED_P (p) = addressable;
2349 TREE_ADDRESSABLE (p) = 0;
2350 layout_decl (p, 0);
2351 (*args)[i] = p;
2352
2353 /* Build a second synthetic decl. */
2354 decl = build_decl (EXPR_LOCATION (p),
2355 PARM_DECL, NULL_TREE, subtype);
2356 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2357 DECL_ARTIFICIAL (decl) = addressable;
2358 DECL_IGNORED_P (decl) = addressable;
2359 layout_decl (decl, 0);
2360 args->safe_insert (++i, decl);
2361 }
2362 }
2363 }
2364
2365 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2366 the hidden struct return argument, and (abi willing) complex args.
2367 Return the new parameter list. */
2368
2369 static vec<tree>
assign_parms_augmented_arg_list(struct assign_parm_data_all * all)2370 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2371 {
2372 tree fndecl = current_function_decl;
2373 tree fntype = TREE_TYPE (fndecl);
2374 vec<tree> fnargs = vNULL;
2375 tree arg;
2376
2377 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2378 fnargs.safe_push (arg);
2379
2380 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2381
2382 /* If struct value address is treated as the first argument, make it so. */
2383 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2384 && ! cfun->returns_pcc_struct
2385 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2386 {
2387 tree type = build_pointer_type (TREE_TYPE (fntype));
2388 tree decl;
2389
2390 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2391 PARM_DECL, get_identifier (".result_ptr"), type);
2392 DECL_ARG_TYPE (decl) = type;
2393 DECL_ARTIFICIAL (decl) = 1;
2394 DECL_NAMELESS (decl) = 1;
2395 TREE_CONSTANT (decl) = 1;
2396 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2397 changes, the end of the RESULT_DECL handling block in
2398 use_register_for_decl must be adjusted to match. */
2399
2400 DECL_CHAIN (decl) = all->orig_fnargs;
2401 all->orig_fnargs = decl;
2402 fnargs.safe_insert (0, decl);
2403
2404 all->function_result_decl = decl;
2405
2406 /* If function is instrumented then bounds of the
2407 passed structure address is the second argument. */
2408 if (chkp_function_instrumented_p (fndecl))
2409 {
2410 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2411 PARM_DECL, get_identifier (".result_bnd"),
2412 pointer_bounds_type_node);
2413 DECL_ARG_TYPE (decl) = pointer_bounds_type_node;
2414 DECL_ARTIFICIAL (decl) = 1;
2415 DECL_NAMELESS (decl) = 1;
2416 TREE_CONSTANT (decl) = 1;
2417
2418 DECL_CHAIN (decl) = DECL_CHAIN (all->orig_fnargs);
2419 DECL_CHAIN (all->orig_fnargs) = decl;
2420 fnargs.safe_insert (1, decl);
2421 }
2422 }
2423
2424 /* If the target wants to split complex arguments into scalars, do so. */
2425 if (targetm.calls.split_complex_arg)
2426 split_complex_args (&fnargs);
2427
2428 return fnargs;
2429 }
2430
2431 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2432 data for the parameter. Incorporate ABI specifics such as pass-by-
2433 reference and type promotion. */
2434
2435 static void
assign_parm_find_data_types(struct assign_parm_data_all * all,tree parm,struct assign_parm_data_one * data)2436 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2437 struct assign_parm_data_one *data)
2438 {
2439 tree nominal_type, passed_type;
2440 machine_mode nominal_mode, passed_mode, promoted_mode;
2441 int unsignedp;
2442
2443 memset (data, 0, sizeof (*data));
2444
2445 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2446 if (!cfun->stdarg)
2447 data->named_arg = 1; /* No variadic parms. */
2448 else if (DECL_CHAIN (parm))
2449 data->named_arg = 1; /* Not the last non-variadic parm. */
2450 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2451 data->named_arg = 1; /* Only variadic ones are unnamed. */
2452 else
2453 data->named_arg = 0; /* Treat as variadic. */
2454
2455 nominal_type = TREE_TYPE (parm);
2456 passed_type = DECL_ARG_TYPE (parm);
2457
2458 /* Look out for errors propagating this far. Also, if the parameter's
2459 type is void then its value doesn't matter. */
2460 if (TREE_TYPE (parm) == error_mark_node
2461 /* This can happen after weird syntax errors
2462 or if an enum type is defined among the parms. */
2463 || TREE_CODE (parm) != PARM_DECL
2464 || passed_type == NULL
2465 || VOID_TYPE_P (nominal_type))
2466 {
2467 nominal_type = passed_type = void_type_node;
2468 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2469 goto egress;
2470 }
2471
2472 /* Find mode of arg as it is passed, and mode of arg as it should be
2473 during execution of this function. */
2474 passed_mode = TYPE_MODE (passed_type);
2475 nominal_mode = TYPE_MODE (nominal_type);
2476
2477 /* If the parm is to be passed as a transparent union or record, use the
2478 type of the first field for the tests below. We have already verified
2479 that the modes are the same. */
2480 if (RECORD_OR_UNION_TYPE_P (passed_type)
2481 && TYPE_TRANSPARENT_AGGR (passed_type))
2482 passed_type = TREE_TYPE (first_field (passed_type));
2483
2484 /* See if this arg was passed by invisible reference. */
2485 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2486 passed_type, data->named_arg))
2487 {
2488 passed_type = nominal_type = build_pointer_type (passed_type);
2489 data->passed_pointer = true;
2490 passed_mode = nominal_mode = TYPE_MODE (nominal_type);
2491 }
2492
2493 /* Find mode as it is passed by the ABI. */
2494 unsignedp = TYPE_UNSIGNED (passed_type);
2495 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2496 TREE_TYPE (current_function_decl), 0);
2497
2498 egress:
2499 data->nominal_type = nominal_type;
2500 data->passed_type = passed_type;
2501 data->nominal_mode = nominal_mode;
2502 data->passed_mode = passed_mode;
2503 data->promoted_mode = promoted_mode;
2504 }
2505
2506 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2507
2508 static void
assign_parms_setup_varargs(struct assign_parm_data_all * all,struct assign_parm_data_one * data,bool no_rtl)2509 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2510 struct assign_parm_data_one *data, bool no_rtl)
2511 {
2512 int varargs_pretend_bytes = 0;
2513
2514 targetm.calls.setup_incoming_varargs (all->args_so_far,
2515 data->promoted_mode,
2516 data->passed_type,
2517 &varargs_pretend_bytes, no_rtl);
2518
2519 /* If the back-end has requested extra stack space, record how much is
2520 needed. Do not change pretend_args_size otherwise since it may be
2521 nonzero from an earlier partial argument. */
2522 if (varargs_pretend_bytes > 0)
2523 all->pretend_args_size = varargs_pretend_bytes;
2524 }
2525
2526 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2527 the incoming location of the current parameter. */
2528
2529 static void
assign_parm_find_entry_rtl(struct assign_parm_data_all * all,struct assign_parm_data_one * data)2530 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2531 struct assign_parm_data_one *data)
2532 {
2533 HOST_WIDE_INT pretend_bytes = 0;
2534 rtx entry_parm;
2535 bool in_regs;
2536
2537 if (data->promoted_mode == VOIDmode)
2538 {
2539 data->entry_parm = data->stack_parm = const0_rtx;
2540 return;
2541 }
2542
2543 targetm.calls.warn_parameter_passing_abi (all->args_so_far,
2544 data->passed_type);
2545
2546 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2547 data->promoted_mode,
2548 data->passed_type,
2549 data->named_arg);
2550
2551 if (entry_parm == 0)
2552 data->promoted_mode = data->passed_mode;
2553
2554 /* Determine parm's home in the stack, in case it arrives in the stack
2555 or we should pretend it did. Compute the stack position and rtx where
2556 the argument arrives and its size.
2557
2558 There is one complexity here: If this was a parameter that would
2559 have been passed in registers, but wasn't only because it is
2560 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2561 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2562 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2563 as it was the previous time. */
2564 in_regs = (entry_parm != 0) || POINTER_BOUNDS_TYPE_P (data->passed_type);
2565 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2566 in_regs = true;
2567 #endif
2568 if (!in_regs && !data->named_arg)
2569 {
2570 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2571 {
2572 rtx tem;
2573 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2574 data->promoted_mode,
2575 data->passed_type, true);
2576 in_regs = tem != NULL;
2577 }
2578 }
2579
2580 /* If this parameter was passed both in registers and in the stack, use
2581 the copy on the stack. */
2582 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2583 data->passed_type))
2584 entry_parm = 0;
2585
2586 if (entry_parm)
2587 {
2588 int partial;
2589
2590 partial = targetm.calls.arg_partial_bytes (all->args_so_far,
2591 data->promoted_mode,
2592 data->passed_type,
2593 data->named_arg);
2594 data->partial = partial;
2595
2596 /* The caller might already have allocated stack space for the
2597 register parameters. */
2598 if (partial != 0 && all->reg_parm_stack_space == 0)
2599 {
2600 /* Part of this argument is passed in registers and part
2601 is passed on the stack. Ask the prologue code to extend
2602 the stack part so that we can recreate the full value.
2603
2604 PRETEND_BYTES is the size of the registers we need to store.
2605 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2606 stack space that the prologue should allocate.
2607
2608 Internally, gcc assumes that the argument pointer is aligned
2609 to STACK_BOUNDARY bits. This is used both for alignment
2610 optimizations (see init_emit) and to locate arguments that are
2611 aligned to more than PARM_BOUNDARY bits. We must preserve this
2612 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2613 a stack boundary. */
2614
2615 /* We assume at most one partial arg, and it must be the first
2616 argument on the stack. */
2617 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2618
2619 pretend_bytes = partial;
2620 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2621
2622 /* We want to align relative to the actual stack pointer, so
2623 don't include this in the stack size until later. */
2624 all->extra_pretend_bytes = all->pretend_args_size;
2625 }
2626 }
2627
2628 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2629 all->reg_parm_stack_space,
2630 entry_parm ? data->partial : 0, current_function_decl,
2631 &all->stack_args_size, &data->locate);
2632
2633 /* Update parm_stack_boundary if this parameter is passed in the
2634 stack. */
2635 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2636 crtl->parm_stack_boundary = data->locate.boundary;
2637
2638 /* Adjust offsets to include the pretend args. */
2639 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2640 data->locate.slot_offset.constant += pretend_bytes;
2641 data->locate.offset.constant += pretend_bytes;
2642
2643 data->entry_parm = entry_parm;
2644 }
2645
2646 /* A subroutine of assign_parms. If there is actually space on the stack
2647 for this parm, count it in stack_args_size and return true. */
2648
2649 static bool
assign_parm_is_stack_parm(struct assign_parm_data_all * all,struct assign_parm_data_one * data)2650 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2651 struct assign_parm_data_one *data)
2652 {
2653 /* Bounds are never passed on the stack to keep compatibility
2654 with not instrumented code. */
2655 if (POINTER_BOUNDS_TYPE_P (data->passed_type))
2656 return false;
2657 /* Trivially true if we've no incoming register. */
2658 else if (data->entry_parm == NULL)
2659 ;
2660 /* Also true if we're partially in registers and partially not,
2661 since we've arranged to drop the entire argument on the stack. */
2662 else if (data->partial != 0)
2663 ;
2664 /* Also true if the target says that it's passed in both registers
2665 and on the stack. */
2666 else if (GET_CODE (data->entry_parm) == PARALLEL
2667 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2668 ;
2669 /* Also true if the target says that there's stack allocated for
2670 all register parameters. */
2671 else if (all->reg_parm_stack_space > 0)
2672 ;
2673 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2674 else
2675 return false;
2676
2677 all->stack_args_size.constant += data->locate.size.constant;
2678 if (data->locate.size.var)
2679 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2680
2681 return true;
2682 }
2683
2684 /* A subroutine of assign_parms. Given that this parameter is allocated
2685 stack space by the ABI, find it. */
2686
2687 static void
assign_parm_find_stack_rtl(tree parm,struct assign_parm_data_one * data)2688 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2689 {
2690 rtx offset_rtx, stack_parm;
2691 unsigned int align, boundary;
2692
2693 /* If we're passing this arg using a reg, make its stack home the
2694 aligned stack slot. */
2695 if (data->entry_parm)
2696 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2697 else
2698 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2699
2700 stack_parm = crtl->args.internal_arg_pointer;
2701 if (offset_rtx != const0_rtx)
2702 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2703 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2704
2705 if (!data->passed_pointer)
2706 {
2707 set_mem_attributes (stack_parm, parm, 1);
2708 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2709 while promoted mode's size is needed. */
2710 if (data->promoted_mode != BLKmode
2711 && data->promoted_mode != DECL_MODE (parm))
2712 {
2713 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2714 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2715 {
2716 poly_int64 offset = subreg_lowpart_offset (DECL_MODE (parm),
2717 data->promoted_mode);
2718 if (maybe_ne (offset, 0))
2719 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2720 }
2721 }
2722 }
2723
2724 boundary = data->locate.boundary;
2725 align = BITS_PER_UNIT;
2726
2727 /* If we're padding upward, we know that the alignment of the slot
2728 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2729 intentionally forcing upward padding. Otherwise we have to come
2730 up with a guess at the alignment based on OFFSET_RTX. */
2731 poly_int64 offset;
2732 if (data->locate.where_pad != PAD_DOWNWARD || data->entry_parm)
2733 align = boundary;
2734 else if (poly_int_rtx_p (offset_rtx, &offset))
2735 {
2736 align = least_bit_hwi (boundary);
2737 unsigned int offset_align = known_alignment (offset) * BITS_PER_UNIT;
2738 if (offset_align != 0)
2739 align = MIN (align, offset_align);
2740 }
2741 set_mem_align (stack_parm, align);
2742
2743 if (data->entry_parm)
2744 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2745
2746 data->stack_parm = stack_parm;
2747 }
2748
2749 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2750 always valid and contiguous. */
2751
2752 static void
assign_parm_adjust_entry_rtl(struct assign_parm_data_one * data)2753 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2754 {
2755 rtx entry_parm = data->entry_parm;
2756 rtx stack_parm = data->stack_parm;
2757
2758 /* If this parm was passed part in regs and part in memory, pretend it
2759 arrived entirely in memory by pushing the register-part onto the stack.
2760 In the special case of a DImode or DFmode that is split, we could put
2761 it together in a pseudoreg directly, but for now that's not worth
2762 bothering with. */
2763 if (data->partial != 0)
2764 {
2765 /* Handle calls that pass values in multiple non-contiguous
2766 locations. The Irix 6 ABI has examples of this. */
2767 if (GET_CODE (entry_parm) == PARALLEL)
2768 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2769 data->passed_type,
2770 int_size_in_bytes (data->passed_type));
2771 else
2772 {
2773 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2774 move_block_from_reg (REGNO (entry_parm),
2775 validize_mem (copy_rtx (stack_parm)),
2776 data->partial / UNITS_PER_WORD);
2777 }
2778
2779 entry_parm = stack_parm;
2780 }
2781
2782 /* If we didn't decide this parm came in a register, by default it came
2783 on the stack. */
2784 else if (entry_parm == NULL)
2785 entry_parm = stack_parm;
2786
2787 /* When an argument is passed in multiple locations, we can't make use
2788 of this information, but we can save some copying if the whole argument
2789 is passed in a single register. */
2790 else if (GET_CODE (entry_parm) == PARALLEL
2791 && data->nominal_mode != BLKmode
2792 && data->passed_mode != BLKmode)
2793 {
2794 size_t i, len = XVECLEN (entry_parm, 0);
2795
2796 for (i = 0; i < len; i++)
2797 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2798 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2799 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2800 == data->passed_mode)
2801 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2802 {
2803 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2804 break;
2805 }
2806 }
2807
2808 data->entry_parm = entry_parm;
2809 }
2810
2811 /* A subroutine of assign_parms. Reconstitute any values which were
2812 passed in multiple registers and would fit in a single register. */
2813
2814 static void
assign_parm_remove_parallels(struct assign_parm_data_one * data)2815 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2816 {
2817 rtx entry_parm = data->entry_parm;
2818
2819 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2820 This can be done with register operations rather than on the
2821 stack, even if we will store the reconstituted parameter on the
2822 stack later. */
2823 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2824 {
2825 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2826 emit_group_store (parmreg, entry_parm, data->passed_type,
2827 GET_MODE_SIZE (GET_MODE (entry_parm)));
2828 entry_parm = parmreg;
2829 }
2830
2831 data->entry_parm = entry_parm;
2832 }
2833
2834 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2835 always valid and properly aligned. */
2836
2837 static void
assign_parm_adjust_stack_rtl(struct assign_parm_data_one * data)2838 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2839 {
2840 rtx stack_parm = data->stack_parm;
2841
2842 /* If we can't trust the parm stack slot to be aligned enough for its
2843 ultimate type, don't use that slot after entry. We'll make another
2844 stack slot, if we need one. */
2845 if (stack_parm
2846 && ((STRICT_ALIGNMENT
2847 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2848 || (data->nominal_type
2849 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2850 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2851 stack_parm = NULL;
2852
2853 /* If parm was passed in memory, and we need to convert it on entry,
2854 don't store it back in that same slot. */
2855 else if (data->entry_parm == stack_parm
2856 && data->nominal_mode != BLKmode
2857 && data->nominal_mode != data->passed_mode)
2858 stack_parm = NULL;
2859
2860 /* If stack protection is in effect for this function, don't leave any
2861 pointers in their passed stack slots. */
2862 else if (crtl->stack_protect_guard
2863 && (flag_stack_protect == 2
2864 || data->passed_pointer
2865 || POINTER_TYPE_P (data->nominal_type)))
2866 stack_parm = NULL;
2867
2868 data->stack_parm = stack_parm;
2869 }
2870
2871 /* A subroutine of assign_parms. Return true if the current parameter
2872 should be stored as a BLKmode in the current frame. */
2873
2874 static bool
assign_parm_setup_block_p(struct assign_parm_data_one * data)2875 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2876 {
2877 if (data->nominal_mode == BLKmode)
2878 return true;
2879 if (GET_MODE (data->entry_parm) == BLKmode)
2880 return true;
2881
2882 #ifdef BLOCK_REG_PADDING
2883 /* Only assign_parm_setup_block knows how to deal with register arguments
2884 that are padded at the least significant end. */
2885 if (REG_P (data->entry_parm)
2886 && known_lt (GET_MODE_SIZE (data->promoted_mode), UNITS_PER_WORD)
2887 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2888 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2889 return true;
2890 #endif
2891
2892 return false;
2893 }
2894
2895 /* A subroutine of assign_parms. Arrange for the parameter to be
2896 present and valid in DATA->STACK_RTL. */
2897
2898 static void
assign_parm_setup_block(struct assign_parm_data_all * all,tree parm,struct assign_parm_data_one * data)2899 assign_parm_setup_block (struct assign_parm_data_all *all,
2900 tree parm, struct assign_parm_data_one *data)
2901 {
2902 rtx entry_parm = data->entry_parm;
2903 rtx stack_parm = data->stack_parm;
2904 rtx target_reg = NULL_RTX;
2905 bool in_conversion_seq = false;
2906 HOST_WIDE_INT size;
2907 HOST_WIDE_INT size_stored;
2908
2909 if (GET_CODE (entry_parm) == PARALLEL)
2910 entry_parm = emit_group_move_into_temps (entry_parm);
2911
2912 /* If we want the parameter in a pseudo, don't use a stack slot. */
2913 if (is_gimple_reg (parm) && use_register_for_decl (parm))
2914 {
2915 tree def = ssa_default_def (cfun, parm);
2916 gcc_assert (def);
2917 machine_mode mode = promote_ssa_mode (def, NULL);
2918 rtx reg = gen_reg_rtx (mode);
2919 if (GET_CODE (reg) != CONCAT)
2920 stack_parm = reg;
2921 else
2922 {
2923 target_reg = reg;
2924 /* Avoid allocating a stack slot, if there isn't one
2925 preallocated by the ABI. It might seem like we should
2926 always prefer a pseudo, but converting between
2927 floating-point and integer modes goes through the stack
2928 on various machines, so it's better to use the reserved
2929 stack slot than to risk wasting it and allocating more
2930 for the conversion. */
2931 if (stack_parm == NULL_RTX)
2932 {
2933 int save = generating_concat_p;
2934 generating_concat_p = 0;
2935 stack_parm = gen_reg_rtx (mode);
2936 generating_concat_p = save;
2937 }
2938 }
2939 data->stack_parm = NULL;
2940 }
2941
2942 size = int_size_in_bytes (data->passed_type);
2943 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2944 if (stack_parm == 0)
2945 {
2946 SET_DECL_ALIGN (parm, MAX (DECL_ALIGN (parm), BITS_PER_WORD));
2947 stack_parm = assign_stack_local (BLKmode, size_stored,
2948 DECL_ALIGN (parm));
2949 if (known_eq (GET_MODE_SIZE (GET_MODE (entry_parm)), size))
2950 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2951 set_mem_attributes (stack_parm, parm, 1);
2952 }
2953
2954 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2955 calls that pass values in multiple non-contiguous locations. */
2956 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2957 {
2958 rtx mem;
2959
2960 /* Note that we will be storing an integral number of words.
2961 So we have to be careful to ensure that we allocate an
2962 integral number of words. We do this above when we call
2963 assign_stack_local if space was not allocated in the argument
2964 list. If it was, this will not work if PARM_BOUNDARY is not
2965 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2966 if it becomes a problem. Exception is when BLKmode arrives
2967 with arguments not conforming to word_mode. */
2968
2969 if (data->stack_parm == 0)
2970 ;
2971 else if (GET_CODE (entry_parm) == PARALLEL)
2972 ;
2973 else
2974 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2975
2976 mem = validize_mem (copy_rtx (stack_parm));
2977
2978 /* Handle values in multiple non-contiguous locations. */
2979 if (GET_CODE (entry_parm) == PARALLEL && !MEM_P (mem))
2980 emit_group_store (mem, entry_parm, data->passed_type, size);
2981 else if (GET_CODE (entry_parm) == PARALLEL)
2982 {
2983 push_to_sequence2 (all->first_conversion_insn,
2984 all->last_conversion_insn);
2985 emit_group_store (mem, entry_parm, data->passed_type, size);
2986 all->first_conversion_insn = get_insns ();
2987 all->last_conversion_insn = get_last_insn ();
2988 end_sequence ();
2989 in_conversion_seq = true;
2990 }
2991
2992 else if (size == 0)
2993 ;
2994
2995 /* If SIZE is that of a mode no bigger than a word, just use
2996 that mode's store operation. */
2997 else if (size <= UNITS_PER_WORD)
2998 {
2999 unsigned int bits = size * BITS_PER_UNIT;
3000 machine_mode mode = int_mode_for_size (bits, 0).else_blk ();
3001
3002 if (mode != BLKmode
3003 #ifdef BLOCK_REG_PADDING
3004 && (size == UNITS_PER_WORD
3005 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
3006 != (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
3007 #endif
3008 )
3009 {
3010 rtx reg;
3011
3012 /* We are really truncating a word_mode value containing
3013 SIZE bytes into a value of mode MODE. If such an
3014 operation requires no actual instructions, we can refer
3015 to the value directly in mode MODE, otherwise we must
3016 start with the register in word_mode and explicitly
3017 convert it. */
3018 if (targetm.truly_noop_truncation (size * BITS_PER_UNIT,
3019 BITS_PER_WORD))
3020 reg = gen_rtx_REG (mode, REGNO (entry_parm));
3021 else
3022 {
3023 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3024 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
3025 }
3026 emit_move_insn (change_address (mem, mode, 0), reg);
3027 }
3028
3029 #ifdef BLOCK_REG_PADDING
3030 /* Storing the register in memory as a full word, as
3031 move_block_from_reg below would do, and then using the
3032 MEM in a smaller mode, has the effect of shifting right
3033 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3034 shifting must be explicit. */
3035 else if (!MEM_P (mem))
3036 {
3037 rtx x;
3038
3039 /* If the assert below fails, we should have taken the
3040 mode != BLKmode path above, unless we have downward
3041 padding of smaller-than-word arguments on a machine
3042 with little-endian bytes, which would likely require
3043 additional changes to work correctly. */
3044 gcc_checking_assert (BYTES_BIG_ENDIAN
3045 && (BLOCK_REG_PADDING (mode,
3046 data->passed_type, 1)
3047 == PAD_UPWARD));
3048
3049 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3050
3051 x = gen_rtx_REG (word_mode, REGNO (entry_parm));
3052 x = expand_shift (RSHIFT_EXPR, word_mode, x, by,
3053 NULL_RTX, 1);
3054 x = force_reg (word_mode, x);
3055 x = gen_lowpart_SUBREG (GET_MODE (mem), x);
3056
3057 emit_move_insn (mem, x);
3058 }
3059 #endif
3060
3061 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3062 machine must be aligned to the left before storing
3063 to memory. Note that the previous test doesn't
3064 handle all cases (e.g. SIZE == 3). */
3065 else if (size != UNITS_PER_WORD
3066 #ifdef BLOCK_REG_PADDING
3067 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
3068 == PAD_DOWNWARD)
3069 #else
3070 && BYTES_BIG_ENDIAN
3071 #endif
3072 )
3073 {
3074 rtx tem, x;
3075 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3076 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3077
3078 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
3079 tem = change_address (mem, word_mode, 0);
3080 emit_move_insn (tem, x);
3081 }
3082 else
3083 move_block_from_reg (REGNO (entry_parm), mem,
3084 size_stored / UNITS_PER_WORD);
3085 }
3086 else if (!MEM_P (mem))
3087 {
3088 gcc_checking_assert (size > UNITS_PER_WORD);
3089 #ifdef BLOCK_REG_PADDING
3090 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem),
3091 data->passed_type, 0)
3092 == PAD_UPWARD);
3093 #endif
3094 emit_move_insn (mem, entry_parm);
3095 }
3096 else
3097 move_block_from_reg (REGNO (entry_parm), mem,
3098 size_stored / UNITS_PER_WORD);
3099 }
3100 else if (data->stack_parm == 0 && !TYPE_EMPTY_P (data->passed_type))
3101 {
3102 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3103 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
3104 BLOCK_OP_NORMAL);
3105 all->first_conversion_insn = get_insns ();
3106 all->last_conversion_insn = get_last_insn ();
3107 end_sequence ();
3108 in_conversion_seq = true;
3109 }
3110
3111 if (target_reg)
3112 {
3113 if (!in_conversion_seq)
3114 emit_move_insn (target_reg, stack_parm);
3115 else
3116 {
3117 push_to_sequence2 (all->first_conversion_insn,
3118 all->last_conversion_insn);
3119 emit_move_insn (target_reg, stack_parm);
3120 all->first_conversion_insn = get_insns ();
3121 all->last_conversion_insn = get_last_insn ();
3122 end_sequence ();
3123 }
3124 stack_parm = target_reg;
3125 }
3126
3127 data->stack_parm = stack_parm;
3128 set_parm_rtl (parm, stack_parm);
3129 }
3130
3131 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3132 parameter. Get it there. Perform all ABI specified conversions. */
3133
3134 static void
assign_parm_setup_reg(struct assign_parm_data_all * all,tree parm,struct assign_parm_data_one * data)3135 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
3136 struct assign_parm_data_one *data)
3137 {
3138 rtx parmreg, validated_mem;
3139 rtx equiv_stack_parm;
3140 machine_mode promoted_nominal_mode;
3141 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
3142 bool did_conversion = false;
3143 bool need_conversion, moved;
3144 rtx rtl;
3145
3146 /* Store the parm in a pseudoregister during the function, but we may
3147 need to do it in a wider mode. Using 2 here makes the result
3148 consistent with promote_decl_mode and thus expand_expr_real_1. */
3149 promoted_nominal_mode
3150 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
3151 TREE_TYPE (current_function_decl), 2);
3152
3153 parmreg = gen_reg_rtx (promoted_nominal_mode);
3154 if (!DECL_ARTIFICIAL (parm))
3155 mark_user_reg (parmreg);
3156
3157 /* If this was an item that we received a pointer to,
3158 set rtl appropriately. */
3159 if (data->passed_pointer)
3160 {
3161 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
3162 set_mem_attributes (rtl, parm, 1);
3163 }
3164 else
3165 rtl = parmreg;
3166
3167 assign_parm_remove_parallels (data);
3168
3169 /* Copy the value into the register, thus bridging between
3170 assign_parm_find_data_types and expand_expr_real_1. */
3171
3172 equiv_stack_parm = data->stack_parm;
3173 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3174
3175 need_conversion = (data->nominal_mode != data->passed_mode
3176 || promoted_nominal_mode != data->promoted_mode);
3177 moved = false;
3178
3179 if (need_conversion
3180 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3181 && data->nominal_mode == data->passed_mode
3182 && data->nominal_mode == GET_MODE (data->entry_parm))
3183 {
3184 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3185 mode, by the caller. We now have to convert it to
3186 NOMINAL_MODE, if different. However, PARMREG may be in
3187 a different mode than NOMINAL_MODE if it is being stored
3188 promoted.
3189
3190 If ENTRY_PARM is a hard register, it might be in a register
3191 not valid for operating in its mode (e.g., an odd-numbered
3192 register for a DFmode). In that case, moves are the only
3193 thing valid, so we can't do a convert from there. This
3194 occurs when the calling sequence allow such misaligned
3195 usages.
3196
3197 In addition, the conversion may involve a call, which could
3198 clobber parameters which haven't been copied to pseudo
3199 registers yet.
3200
3201 First, we try to emit an insn which performs the necessary
3202 conversion. We verify that this insn does not clobber any
3203 hard registers. */
3204
3205 enum insn_code icode;
3206 rtx op0, op1;
3207
3208 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3209 unsignedp);
3210
3211 op0 = parmreg;
3212 op1 = validated_mem;
3213 if (icode != CODE_FOR_nothing
3214 && insn_operand_matches (icode, 0, op0)
3215 && insn_operand_matches (icode, 1, op1))
3216 {
3217 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3218 rtx_insn *insn, *insns;
3219 rtx t = op1;
3220 HARD_REG_SET hardregs;
3221
3222 start_sequence ();
3223 /* If op1 is a hard register that is likely spilled, first
3224 force it into a pseudo, otherwise combiner might extend
3225 its lifetime too much. */
3226 if (GET_CODE (t) == SUBREG)
3227 t = SUBREG_REG (t);
3228 if (REG_P (t)
3229 && HARD_REGISTER_P (t)
3230 && ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
3231 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
3232 {
3233 t = gen_reg_rtx (GET_MODE (op1));
3234 emit_move_insn (t, op1);
3235 }
3236 else
3237 t = op1;
3238 rtx_insn *pat = gen_extend_insn (op0, t, promoted_nominal_mode,
3239 data->passed_mode, unsignedp);
3240 emit_insn (pat);
3241 insns = get_insns ();
3242
3243 moved = true;
3244 CLEAR_HARD_REG_SET (hardregs);
3245 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3246 {
3247 if (INSN_P (insn))
3248 note_stores (PATTERN (insn), record_hard_reg_sets,
3249 &hardregs);
3250 if (!hard_reg_set_empty_p (hardregs))
3251 moved = false;
3252 }
3253
3254 end_sequence ();
3255
3256 if (moved)
3257 {
3258 emit_insn (insns);
3259 if (equiv_stack_parm != NULL_RTX)
3260 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3261 equiv_stack_parm);
3262 }
3263 }
3264 }
3265
3266 if (moved)
3267 /* Nothing to do. */
3268 ;
3269 else if (need_conversion)
3270 {
3271 /* We did not have an insn to convert directly, or the sequence
3272 generated appeared unsafe. We must first copy the parm to a
3273 pseudo reg, and save the conversion until after all
3274 parameters have been moved. */
3275
3276 int save_tree_used;
3277 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3278
3279 emit_move_insn (tempreg, validated_mem);
3280
3281 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3282 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3283
3284 if (partial_subreg_p (tempreg)
3285 && GET_MODE (tempreg) == data->nominal_mode
3286 && REG_P (SUBREG_REG (tempreg))
3287 && data->nominal_mode == data->passed_mode
3288 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm))
3289 {
3290 /* The argument is already sign/zero extended, so note it
3291 into the subreg. */
3292 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3293 SUBREG_PROMOTED_SET (tempreg, unsignedp);
3294 }
3295
3296 /* TREE_USED gets set erroneously during expand_assignment. */
3297 save_tree_used = TREE_USED (parm);
3298 SET_DECL_RTL (parm, rtl);
3299 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3300 SET_DECL_RTL (parm, NULL_RTX);
3301 TREE_USED (parm) = save_tree_used;
3302 all->first_conversion_insn = get_insns ();
3303 all->last_conversion_insn = get_last_insn ();
3304 end_sequence ();
3305
3306 did_conversion = true;
3307 }
3308 else
3309 emit_move_insn (parmreg, validated_mem);
3310
3311 /* If we were passed a pointer but the actual value can safely live
3312 in a register, retrieve it and use it directly. */
3313 if (data->passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3314 {
3315 /* We can't use nominal_mode, because it will have been set to
3316 Pmode above. We must use the actual mode of the parm. */
3317 if (use_register_for_decl (parm))
3318 {
3319 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3320 mark_user_reg (parmreg);
3321 }
3322 else
3323 {
3324 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3325 TYPE_MODE (TREE_TYPE (parm)),
3326 TYPE_ALIGN (TREE_TYPE (parm)));
3327 parmreg
3328 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3329 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3330 align);
3331 set_mem_attributes (parmreg, parm, 1);
3332 }
3333
3334 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3335 the debug info in case it is not legitimate. */
3336 if (GET_MODE (parmreg) != GET_MODE (rtl))
3337 {
3338 rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
3339 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3340
3341 push_to_sequence2 (all->first_conversion_insn,
3342 all->last_conversion_insn);
3343 emit_move_insn (tempreg, rtl);
3344 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3345 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
3346 tempreg);
3347 all->first_conversion_insn = get_insns ();
3348 all->last_conversion_insn = get_last_insn ();
3349 end_sequence ();
3350
3351 did_conversion = true;
3352 }
3353 else
3354 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
3355
3356 rtl = parmreg;
3357
3358 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3359 now the parm. */
3360 data->stack_parm = NULL;
3361 }
3362
3363 set_parm_rtl (parm, rtl);
3364
3365 /* Mark the register as eliminable if we did no conversion and it was
3366 copied from memory at a fixed offset, and the arg pointer was not
3367 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3368 offset formed an invalid address, such memory-equivalences as we
3369 make here would screw up life analysis for it. */
3370 if (data->nominal_mode == data->passed_mode
3371 && !did_conversion
3372 && data->stack_parm != 0
3373 && MEM_P (data->stack_parm)
3374 && data->locate.offset.var == 0
3375 && reg_mentioned_p (virtual_incoming_args_rtx,
3376 XEXP (data->stack_parm, 0)))
3377 {
3378 rtx_insn *linsn = get_last_insn ();
3379 rtx_insn *sinsn;
3380 rtx set;
3381
3382 /* Mark complex types separately. */
3383 if (GET_CODE (parmreg) == CONCAT)
3384 {
3385 scalar_mode submode = GET_MODE_INNER (GET_MODE (parmreg));
3386 int regnor = REGNO (XEXP (parmreg, 0));
3387 int regnoi = REGNO (XEXP (parmreg, 1));
3388 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3389 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3390 GET_MODE_SIZE (submode));
3391
3392 /* Scan backwards for the set of the real and
3393 imaginary parts. */
3394 for (sinsn = linsn; sinsn != 0;
3395 sinsn = prev_nonnote_insn (sinsn))
3396 {
3397 set = single_set (sinsn);
3398 if (set == 0)
3399 continue;
3400
3401 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3402 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3403 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3404 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3405 }
3406 }
3407 else
3408 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3409 }
3410
3411 /* For pointer data type, suggest pointer register. */
3412 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3413 mark_reg_pointer (parmreg,
3414 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3415 }
3416
3417 /* A subroutine of assign_parms. Allocate stack space to hold the current
3418 parameter. Get it there. Perform all ABI specified conversions. */
3419
3420 static void
assign_parm_setup_stack(struct assign_parm_data_all * all,tree parm,struct assign_parm_data_one * data)3421 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3422 struct assign_parm_data_one *data)
3423 {
3424 /* Value must be stored in the stack slot STACK_PARM during function
3425 execution. */
3426 bool to_conversion = false;
3427
3428 assign_parm_remove_parallels (data);
3429
3430 if (data->promoted_mode != data->nominal_mode)
3431 {
3432 /* Conversion is required. */
3433 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3434
3435 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3436
3437 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3438 to_conversion = true;
3439
3440 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3441 TYPE_UNSIGNED (TREE_TYPE (parm)));
3442
3443 if (data->stack_parm)
3444 {
3445 poly_int64 offset
3446 = subreg_lowpart_offset (data->nominal_mode,
3447 GET_MODE (data->stack_parm));
3448 /* ??? This may need a big-endian conversion on sparc64. */
3449 data->stack_parm
3450 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3451 if (maybe_ne (offset, 0) && MEM_OFFSET_KNOWN_P (data->stack_parm))
3452 set_mem_offset (data->stack_parm,
3453 MEM_OFFSET (data->stack_parm) + offset);
3454 }
3455 }
3456
3457 if (data->entry_parm != data->stack_parm)
3458 {
3459 rtx src, dest;
3460
3461 if (data->stack_parm == 0)
3462 {
3463 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3464 GET_MODE (data->entry_parm),
3465 TYPE_ALIGN (data->passed_type));
3466 data->stack_parm
3467 = assign_stack_local (GET_MODE (data->entry_parm),
3468 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3469 align);
3470 set_mem_attributes (data->stack_parm, parm, 1);
3471 }
3472
3473 dest = validize_mem (copy_rtx (data->stack_parm));
3474 src = validize_mem (copy_rtx (data->entry_parm));
3475
3476 if (TYPE_EMPTY_P (data->passed_type))
3477 /* Empty types don't really need to be copied. */;
3478 else if (MEM_P (src))
3479 {
3480 /* Use a block move to handle potentially misaligned entry_parm. */
3481 if (!to_conversion)
3482 push_to_sequence2 (all->first_conversion_insn,
3483 all->last_conversion_insn);
3484 to_conversion = true;
3485
3486 emit_block_move (dest, src,
3487 GEN_INT (int_size_in_bytes (data->passed_type)),
3488 BLOCK_OP_NORMAL);
3489 }
3490 else
3491 {
3492 if (!REG_P (src))
3493 src = force_reg (GET_MODE (src), src);
3494 emit_move_insn (dest, src);
3495 }
3496 }
3497
3498 if (to_conversion)
3499 {
3500 all->first_conversion_insn = get_insns ();
3501 all->last_conversion_insn = get_last_insn ();
3502 end_sequence ();
3503 }
3504
3505 set_parm_rtl (parm, data->stack_parm);
3506 }
3507
3508 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3509 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3510
3511 static void
assign_parms_unsplit_complex(struct assign_parm_data_all * all,vec<tree> fnargs)3512 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3513 vec<tree> fnargs)
3514 {
3515 tree parm;
3516 tree orig_fnargs = all->orig_fnargs;
3517 unsigned i = 0;
3518
3519 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3520 {
3521 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3522 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3523 {
3524 rtx tmp, real, imag;
3525 scalar_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3526
3527 real = DECL_RTL (fnargs[i]);
3528 imag = DECL_RTL (fnargs[i + 1]);
3529 if (inner != GET_MODE (real))
3530 {
3531 real = gen_lowpart_SUBREG (inner, real);
3532 imag = gen_lowpart_SUBREG (inner, imag);
3533 }
3534
3535 if (TREE_ADDRESSABLE (parm))
3536 {
3537 rtx rmem, imem;
3538 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3539 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3540 DECL_MODE (parm),
3541 TYPE_ALIGN (TREE_TYPE (parm)));
3542
3543 /* split_complex_arg put the real and imag parts in
3544 pseudos. Move them to memory. */
3545 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3546 set_mem_attributes (tmp, parm, 1);
3547 rmem = adjust_address_nv (tmp, inner, 0);
3548 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3549 push_to_sequence2 (all->first_conversion_insn,
3550 all->last_conversion_insn);
3551 emit_move_insn (rmem, real);
3552 emit_move_insn (imem, imag);
3553 all->first_conversion_insn = get_insns ();
3554 all->last_conversion_insn = get_last_insn ();
3555 end_sequence ();
3556 }
3557 else
3558 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3559 set_parm_rtl (parm, tmp);
3560
3561 real = DECL_INCOMING_RTL (fnargs[i]);
3562 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3563 if (inner != GET_MODE (real))
3564 {
3565 real = gen_lowpart_SUBREG (inner, real);
3566 imag = gen_lowpart_SUBREG (inner, imag);
3567 }
3568 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3569 set_decl_incoming_rtl (parm, tmp, false);
3570 i++;
3571 }
3572 }
3573 }
3574
3575 /* Load bounds of PARM from bounds table. */
3576 static void
assign_parm_load_bounds(struct assign_parm_data_one * data,tree parm,rtx entry,unsigned bound_no)3577 assign_parm_load_bounds (struct assign_parm_data_one *data,
3578 tree parm,
3579 rtx entry,
3580 unsigned bound_no)
3581 {
3582 bitmap_iterator bi;
3583 unsigned i, offs = 0;
3584 int bnd_no = -1;
3585 rtx slot = NULL, ptr = NULL;
3586
3587 if (parm)
3588 {
3589 bitmap slots;
3590 bitmap_obstack_initialize (NULL);
3591 slots = BITMAP_ALLOC (NULL);
3592 chkp_find_bound_slots (TREE_TYPE (parm), slots);
3593 EXECUTE_IF_SET_IN_BITMAP (slots, 0, i, bi)
3594 {
3595 if (bound_no)
3596 bound_no--;
3597 else
3598 {
3599 bnd_no = i;
3600 break;
3601 }
3602 }
3603 BITMAP_FREE (slots);
3604 bitmap_obstack_release (NULL);
3605 }
3606
3607 /* We may have bounds not associated with any pointer. */
3608 if (bnd_no != -1)
3609 offs = bnd_no * POINTER_SIZE / BITS_PER_UNIT;
3610
3611 /* Find associated pointer. */
3612 if (bnd_no == -1)
3613 {
3614 /* If bounds are not associated with any bounds,
3615 then it is passed in a register or special slot. */
3616 gcc_assert (data->entry_parm);
3617 ptr = const0_rtx;
3618 }
3619 else if (MEM_P (entry))
3620 slot = adjust_address (entry, Pmode, offs);
3621 else if (REG_P (entry))
3622 ptr = gen_rtx_REG (Pmode, REGNO (entry) + bnd_no);
3623 else if (GET_CODE (entry) == PARALLEL)
3624 ptr = chkp_get_value_with_offs (entry, GEN_INT (offs));
3625 else
3626 gcc_unreachable ();
3627 data->entry_parm = targetm.calls.load_bounds_for_arg (slot, ptr,
3628 data->entry_parm);
3629 }
3630
3631 /* Assign RTL expressions to the function's bounds parameters BNDARGS. */
3632
3633 static void
assign_bounds(vec<bounds_parm_data> & bndargs,struct assign_parm_data_all & all,bool assign_regs,bool assign_special,bool assign_bt)3634 assign_bounds (vec<bounds_parm_data> &bndargs,
3635 struct assign_parm_data_all &all,
3636 bool assign_regs, bool assign_special,
3637 bool assign_bt)
3638 {
3639 unsigned i, pass;
3640 bounds_parm_data *pbdata;
3641
3642 if (!bndargs.exists ())
3643 return;
3644
3645 /* We make few passes to store input bounds. Firstly handle bounds
3646 passed in registers. After that we load bounds passed in special
3647 slots. Finally we load bounds from Bounds Table. */
3648 for (pass = 0; pass < 3; pass++)
3649 FOR_EACH_VEC_ELT (bndargs, i, pbdata)
3650 {
3651 /* Pass 0 => regs only. */
3652 if (pass == 0
3653 && (!assign_regs
3654 ||(!pbdata->parm_data.entry_parm
3655 || GET_CODE (pbdata->parm_data.entry_parm) != REG)))
3656 continue;
3657 /* Pass 1 => slots only. */
3658 else if (pass == 1
3659 && (!assign_special
3660 || (!pbdata->parm_data.entry_parm
3661 || GET_CODE (pbdata->parm_data.entry_parm) == REG)))
3662 continue;
3663 /* Pass 2 => BT only. */
3664 else if (pass == 2
3665 && (!assign_bt
3666 || pbdata->parm_data.entry_parm))
3667 continue;
3668
3669 if (!pbdata->parm_data.entry_parm
3670 || GET_CODE (pbdata->parm_data.entry_parm) != REG)
3671 assign_parm_load_bounds (&pbdata->parm_data, pbdata->ptr_parm,
3672 pbdata->ptr_entry, pbdata->bound_no);
3673
3674 set_decl_incoming_rtl (pbdata->bounds_parm,
3675 pbdata->parm_data.entry_parm, false);
3676
3677 if (assign_parm_setup_block_p (&pbdata->parm_data))
3678 assign_parm_setup_block (&all, pbdata->bounds_parm,
3679 &pbdata->parm_data);
3680 else if (pbdata->parm_data.passed_pointer
3681 || use_register_for_decl (pbdata->bounds_parm))
3682 assign_parm_setup_reg (&all, pbdata->bounds_parm,
3683 &pbdata->parm_data);
3684 else
3685 assign_parm_setup_stack (&all, pbdata->bounds_parm,
3686 &pbdata->parm_data);
3687 }
3688 }
3689
3690 /* Assign RTL expressions to the function's parameters. This may involve
3691 copying them into registers and using those registers as the DECL_RTL. */
3692
3693 static void
assign_parms(tree fndecl)3694 assign_parms (tree fndecl)
3695 {
3696 struct assign_parm_data_all all;
3697 tree parm;
3698 vec<tree> fnargs;
3699 unsigned i, bound_no = 0;
3700 tree last_arg = NULL;
3701 rtx last_arg_entry = NULL;
3702 vec<bounds_parm_data> bndargs = vNULL;
3703 bounds_parm_data bdata;
3704
3705 crtl->args.internal_arg_pointer
3706 = targetm.calls.internal_arg_pointer ();
3707
3708 assign_parms_initialize_all (&all);
3709 fnargs = assign_parms_augmented_arg_list (&all);
3710
3711 FOR_EACH_VEC_ELT (fnargs, i, parm)
3712 {
3713 struct assign_parm_data_one data;
3714
3715 /* Extract the type of PARM; adjust it according to ABI. */
3716 assign_parm_find_data_types (&all, parm, &data);
3717
3718 /* Early out for errors and void parameters. */
3719 if (data.passed_mode == VOIDmode)
3720 {
3721 SET_DECL_RTL (parm, const0_rtx);
3722 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3723 continue;
3724 }
3725
3726 /* Estimate stack alignment from parameter alignment. */
3727 if (SUPPORTS_STACK_ALIGNMENT)
3728 {
3729 unsigned int align
3730 = targetm.calls.function_arg_boundary (data.promoted_mode,
3731 data.passed_type);
3732 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3733 align);
3734 if (TYPE_ALIGN (data.nominal_type) > align)
3735 align = MINIMUM_ALIGNMENT (data.nominal_type,
3736 TYPE_MODE (data.nominal_type),
3737 TYPE_ALIGN (data.nominal_type));
3738 if (crtl->stack_alignment_estimated < align)
3739 {
3740 gcc_assert (!crtl->stack_realign_processed);
3741 crtl->stack_alignment_estimated = align;
3742 }
3743 }
3744
3745 /* Find out where the parameter arrives in this function. */
3746 assign_parm_find_entry_rtl (&all, &data);
3747
3748 /* Find out where stack space for this parameter might be. */
3749 if (assign_parm_is_stack_parm (&all, &data))
3750 {
3751 assign_parm_find_stack_rtl (parm, &data);
3752 assign_parm_adjust_entry_rtl (&data);
3753 /* For arguments that occupy no space in the parameter
3754 passing area, have non-zero size and have address taken,
3755 force creation of a stack slot so that they have distinct
3756 address from other parameters. */
3757 if (TYPE_EMPTY_P (data.passed_type)
3758 && TREE_ADDRESSABLE (parm)
3759 && data.entry_parm == data.stack_parm
3760 && MEM_P (data.entry_parm)
3761 && int_size_in_bytes (data.passed_type))
3762 data.stack_parm = NULL_RTX;
3763 }
3764 if (!POINTER_BOUNDS_TYPE_P (data.passed_type))
3765 {
3766 /* Remember where last non bounds arg was passed in case
3767 we have to load associated bounds for it from Bounds
3768 Table. */
3769 last_arg = parm;
3770 last_arg_entry = data.entry_parm;
3771 bound_no = 0;
3772 }
3773 /* Record permanently how this parm was passed. */
3774 if (data.passed_pointer)
3775 {
3776 rtx incoming_rtl
3777 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3778 data.entry_parm);
3779 set_decl_incoming_rtl (parm, incoming_rtl, true);
3780 }
3781 else
3782 set_decl_incoming_rtl (parm, data.entry_parm, false);
3783
3784 assign_parm_adjust_stack_rtl (&data);
3785
3786 /* Bounds should be loaded in the particular order to
3787 have registers allocated correctly. Collect info about
3788 input bounds and load them later. */
3789 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3790 {
3791 /* Expect bounds in instrumented functions only. */
3792 gcc_assert (chkp_function_instrumented_p (fndecl));
3793
3794 bdata.parm_data = data;
3795 bdata.bounds_parm = parm;
3796 bdata.ptr_parm = last_arg;
3797 bdata.ptr_entry = last_arg_entry;
3798 bdata.bound_no = bound_no;
3799 bndargs.safe_push (bdata);
3800 }
3801 else
3802 {
3803 if (assign_parm_setup_block_p (&data))
3804 assign_parm_setup_block (&all, parm, &data);
3805 else if (data.passed_pointer || use_register_for_decl (parm))
3806 assign_parm_setup_reg (&all, parm, &data);
3807 else
3808 assign_parm_setup_stack (&all, parm, &data);
3809 }
3810
3811 if (cfun->stdarg && !DECL_CHAIN (parm))
3812 {
3813 int pretend_bytes = 0;
3814
3815 assign_parms_setup_varargs (&all, &data, false);
3816
3817 if (chkp_function_instrumented_p (fndecl))
3818 {
3819 /* We expect this is the last parm. Otherwise it is wrong
3820 to assign bounds right now. */
3821 gcc_assert (i == (fnargs.length () - 1));
3822 assign_bounds (bndargs, all, true, false, false);
3823 targetm.calls.setup_incoming_vararg_bounds (all.args_so_far,
3824 data.promoted_mode,
3825 data.passed_type,
3826 &pretend_bytes,
3827 false);
3828 assign_bounds (bndargs, all, false, true, true);
3829 bndargs.release ();
3830 }
3831 }
3832
3833 /* Update info on where next arg arrives in registers. */
3834 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3835 data.passed_type, data.named_arg);
3836
3837 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3838 bound_no++;
3839 }
3840
3841 assign_bounds (bndargs, all, true, true, true);
3842 bndargs.release ();
3843
3844 if (targetm.calls.split_complex_arg)
3845 assign_parms_unsplit_complex (&all, fnargs);
3846
3847 fnargs.release ();
3848
3849 /* Output all parameter conversion instructions (possibly including calls)
3850 now that all parameters have been copied out of hard registers. */
3851 emit_insn (all.first_conversion_insn);
3852
3853 /* Estimate reload stack alignment from scalar return mode. */
3854 if (SUPPORTS_STACK_ALIGNMENT)
3855 {
3856 if (DECL_RESULT (fndecl))
3857 {
3858 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3859 machine_mode mode = TYPE_MODE (type);
3860
3861 if (mode != BLKmode
3862 && mode != VOIDmode
3863 && !AGGREGATE_TYPE_P (type))
3864 {
3865 unsigned int align = GET_MODE_ALIGNMENT (mode);
3866 if (crtl->stack_alignment_estimated < align)
3867 {
3868 gcc_assert (!crtl->stack_realign_processed);
3869 crtl->stack_alignment_estimated = align;
3870 }
3871 }
3872 }
3873 }
3874
3875 /* If we are receiving a struct value address as the first argument, set up
3876 the RTL for the function result. As this might require code to convert
3877 the transmitted address to Pmode, we do this here to ensure that possible
3878 preliminary conversions of the address have been emitted already. */
3879 if (all.function_result_decl)
3880 {
3881 tree result = DECL_RESULT (current_function_decl);
3882 rtx addr = DECL_RTL (all.function_result_decl);
3883 rtx x;
3884
3885 if (DECL_BY_REFERENCE (result))
3886 {
3887 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3888 x = addr;
3889 }
3890 else
3891 {
3892 SET_DECL_VALUE_EXPR (result,
3893 build1 (INDIRECT_REF, TREE_TYPE (result),
3894 all.function_result_decl));
3895 addr = convert_memory_address (Pmode, addr);
3896 x = gen_rtx_MEM (DECL_MODE (result), addr);
3897 set_mem_attributes (x, result, 1);
3898 }
3899
3900 DECL_HAS_VALUE_EXPR_P (result) = 1;
3901
3902 set_parm_rtl (result, x);
3903 }
3904
3905 /* We have aligned all the args, so add space for the pretend args. */
3906 crtl->args.pretend_args_size = all.pretend_args_size;
3907 all.stack_args_size.constant += all.extra_pretend_bytes;
3908 crtl->args.size = all.stack_args_size.constant;
3909
3910 /* Adjust function incoming argument size for alignment and
3911 minimum length. */
3912
3913 crtl->args.size = upper_bound (crtl->args.size, all.reg_parm_stack_space);
3914 crtl->args.size = aligned_upper_bound (crtl->args.size,
3915 PARM_BOUNDARY / BITS_PER_UNIT);
3916
3917 if (ARGS_GROW_DOWNWARD)
3918 {
3919 crtl->args.arg_offset_rtx
3920 = (all.stack_args_size.var == 0
3921 ? gen_int_mode (-all.stack_args_size.constant, Pmode)
3922 : expand_expr (size_diffop (all.stack_args_size.var,
3923 size_int (-all.stack_args_size.constant)),
3924 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3925 }
3926 else
3927 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3928
3929 /* See how many bytes, if any, of its args a function should try to pop
3930 on return. */
3931
3932 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3933 TREE_TYPE (fndecl),
3934 crtl->args.size);
3935
3936 /* For stdarg.h function, save info about
3937 regs and stack space used by the named args. */
3938
3939 crtl->args.info = all.args_so_far_v;
3940
3941 /* Set the rtx used for the function return value. Put this in its
3942 own variable so any optimizers that need this information don't have
3943 to include tree.h. Do this here so it gets done when an inlined
3944 function gets output. */
3945
3946 crtl->return_rtx
3947 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3948 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3949
3950 /* If scalar return value was computed in a pseudo-reg, or was a named
3951 return value that got dumped to the stack, copy that to the hard
3952 return register. */
3953 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3954 {
3955 tree decl_result = DECL_RESULT (fndecl);
3956 rtx decl_rtl = DECL_RTL (decl_result);
3957
3958 if (REG_P (decl_rtl)
3959 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3960 : DECL_REGISTER (decl_result))
3961 {
3962 rtx real_decl_rtl;
3963
3964 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3965 fndecl, true);
3966 if (chkp_function_instrumented_p (fndecl))
3967 crtl->return_bnd
3968 = targetm.calls.chkp_function_value_bounds (TREE_TYPE (decl_result),
3969 fndecl, true);
3970 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3971 /* The delay slot scheduler assumes that crtl->return_rtx
3972 holds the hard register containing the return value, not a
3973 temporary pseudo. */
3974 crtl->return_rtx = real_decl_rtl;
3975 }
3976 }
3977 }
3978
3979 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3980 For all seen types, gimplify their sizes. */
3981
3982 static tree
gimplify_parm_type(tree * tp,int * walk_subtrees,void * data)3983 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3984 {
3985 tree t = *tp;
3986
3987 *walk_subtrees = 0;
3988 if (TYPE_P (t))
3989 {
3990 if (POINTER_TYPE_P (t))
3991 *walk_subtrees = 1;
3992 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3993 && !TYPE_SIZES_GIMPLIFIED (t))
3994 {
3995 gimplify_type_sizes (t, (gimple_seq *) data);
3996 *walk_subtrees = 1;
3997 }
3998 }
3999
4000 return NULL;
4001 }
4002
4003 /* Gimplify the parameter list for current_function_decl. This involves
4004 evaluating SAVE_EXPRs of variable sized parameters and generating code
4005 to implement callee-copies reference parameters. Returns a sequence of
4006 statements to add to the beginning of the function. */
4007
4008 gimple_seq
gimplify_parameters(gimple_seq * cleanup)4009 gimplify_parameters (gimple_seq *cleanup)
4010 {
4011 struct assign_parm_data_all all;
4012 tree parm;
4013 gimple_seq stmts = NULL;
4014 vec<tree> fnargs;
4015 unsigned i;
4016
4017 assign_parms_initialize_all (&all);
4018 fnargs = assign_parms_augmented_arg_list (&all);
4019
4020 FOR_EACH_VEC_ELT (fnargs, i, parm)
4021 {
4022 struct assign_parm_data_one data;
4023
4024 /* Extract the type of PARM; adjust it according to ABI. */
4025 assign_parm_find_data_types (&all, parm, &data);
4026
4027 /* Early out for errors and void parameters. */
4028 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
4029 continue;
4030
4031 /* Update info on where next arg arrives in registers. */
4032 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
4033 data.passed_type, data.named_arg);
4034
4035 /* ??? Once upon a time variable_size stuffed parameter list
4036 SAVE_EXPRs (amongst others) onto a pending sizes list. This
4037 turned out to be less than manageable in the gimple world.
4038 Now we have to hunt them down ourselves. */
4039 walk_tree_without_duplicates (&data.passed_type,
4040 gimplify_parm_type, &stmts);
4041
4042 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
4043 {
4044 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
4045 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
4046 }
4047
4048 if (data.passed_pointer)
4049 {
4050 tree type = TREE_TYPE (data.passed_type);
4051 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
4052 type, data.named_arg))
4053 {
4054 tree local, t;
4055
4056 /* For constant-sized objects, this is trivial; for
4057 variable-sized objects, we have to play games. */
4058 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
4059 && !(flag_stack_check == GENERIC_STACK_CHECK
4060 && compare_tree_int (DECL_SIZE_UNIT (parm),
4061 STACK_CHECK_MAX_VAR_SIZE) > 0))
4062 {
4063 local = create_tmp_var (type, get_name (parm));
4064 DECL_IGNORED_P (local) = 0;
4065 /* If PARM was addressable, move that flag over
4066 to the local copy, as its address will be taken,
4067 not the PARMs. Keep the parms address taken
4068 as we'll query that flag during gimplification. */
4069 if (TREE_ADDRESSABLE (parm))
4070 TREE_ADDRESSABLE (local) = 1;
4071 else if (TREE_CODE (type) == COMPLEX_TYPE
4072 || TREE_CODE (type) == VECTOR_TYPE)
4073 DECL_GIMPLE_REG_P (local) = 1;
4074
4075 if (!is_gimple_reg (local)
4076 && flag_stack_reuse != SR_NONE)
4077 {
4078 tree clobber = build_constructor (type, NULL);
4079 gimple *clobber_stmt;
4080 TREE_THIS_VOLATILE (clobber) = 1;
4081 clobber_stmt = gimple_build_assign (local, clobber);
4082 gimple_seq_add_stmt (cleanup, clobber_stmt);
4083 }
4084 }
4085 else
4086 {
4087 tree ptr_type, addr;
4088
4089 ptr_type = build_pointer_type (type);
4090 addr = create_tmp_reg (ptr_type, get_name (parm));
4091 DECL_IGNORED_P (addr) = 0;
4092 local = build_fold_indirect_ref (addr);
4093
4094 t = build_alloca_call_expr (DECL_SIZE_UNIT (parm),
4095 DECL_ALIGN (parm),
4096 max_int_size_in_bytes (type));
4097 /* The call has been built for a variable-sized object. */
4098 CALL_ALLOCA_FOR_VAR_P (t) = 1;
4099 t = fold_convert (ptr_type, t);
4100 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
4101 gimplify_and_add (t, &stmts);
4102 }
4103
4104 gimplify_assign (local, parm, &stmts);
4105
4106 SET_DECL_VALUE_EXPR (parm, local);
4107 DECL_HAS_VALUE_EXPR_P (parm) = 1;
4108 }
4109 }
4110 }
4111
4112 fnargs.release ();
4113
4114 return stmts;
4115 }
4116
4117 /* Compute the size and offset from the start of the stacked arguments for a
4118 parm passed in mode PASSED_MODE and with type TYPE.
4119
4120 INITIAL_OFFSET_PTR points to the current offset into the stacked
4121 arguments.
4122
4123 The starting offset and size for this parm are returned in
4124 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
4125 nonzero, the offset is that of stack slot, which is returned in
4126 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
4127 padding required from the initial offset ptr to the stack slot.
4128
4129 IN_REGS is nonzero if the argument will be passed in registers. It will
4130 never be set if REG_PARM_STACK_SPACE is not defined.
4131
4132 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
4133 for arguments which are passed in registers.
4134
4135 FNDECL is the function in which the argument was defined.
4136
4137 There are two types of rounding that are done. The first, controlled by
4138 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
4139 argument list to be aligned to the specific boundary (in bits). This
4140 rounding affects the initial and starting offsets, but not the argument
4141 size.
4142
4143 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4144 optionally rounds the size of the parm to PARM_BOUNDARY. The
4145 initial offset is not affected by this rounding, while the size always
4146 is and the starting offset may be. */
4147
4148 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
4149 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
4150 callers pass in the total size of args so far as
4151 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
4152
4153 void
locate_and_pad_parm(machine_mode passed_mode,tree type,int in_regs,int reg_parm_stack_space,int partial,tree fndecl ATTRIBUTE_UNUSED,struct args_size * initial_offset_ptr,struct locate_and_pad_arg_data * locate)4154 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
4155 int reg_parm_stack_space, int partial,
4156 tree fndecl ATTRIBUTE_UNUSED,
4157 struct args_size *initial_offset_ptr,
4158 struct locate_and_pad_arg_data *locate)
4159 {
4160 tree sizetree;
4161 pad_direction where_pad;
4162 unsigned int boundary, round_boundary;
4163 int part_size_in_regs;
4164
4165 /* If we have found a stack parm before we reach the end of the
4166 area reserved for registers, skip that area. */
4167 if (! in_regs)
4168 {
4169 if (reg_parm_stack_space > 0)
4170 {
4171 if (initial_offset_ptr->var
4172 || !ordered_p (initial_offset_ptr->constant,
4173 reg_parm_stack_space))
4174 {
4175 initial_offset_ptr->var
4176 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4177 ssize_int (reg_parm_stack_space));
4178 initial_offset_ptr->constant = 0;
4179 }
4180 else
4181 initial_offset_ptr->constant
4182 = ordered_max (initial_offset_ptr->constant,
4183 reg_parm_stack_space);
4184 }
4185 }
4186
4187 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
4188
4189 sizetree = (type
4190 ? arg_size_in_bytes (type)
4191 : size_int (GET_MODE_SIZE (passed_mode)));
4192 where_pad = targetm.calls.function_arg_padding (passed_mode, type);
4193 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
4194 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
4195 type);
4196 locate->where_pad = where_pad;
4197
4198 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4199 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
4200 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
4201
4202 locate->boundary = boundary;
4203
4204 if (SUPPORTS_STACK_ALIGNMENT)
4205 {
4206 /* stack_alignment_estimated can't change after stack has been
4207 realigned. */
4208 if (crtl->stack_alignment_estimated < boundary)
4209 {
4210 if (!crtl->stack_realign_processed)
4211 crtl->stack_alignment_estimated = boundary;
4212 else
4213 {
4214 /* If stack is realigned and stack alignment value
4215 hasn't been finalized, it is OK not to increase
4216 stack_alignment_estimated. The bigger alignment
4217 requirement is recorded in stack_alignment_needed
4218 below. */
4219 gcc_assert (!crtl->stack_realign_finalized
4220 && crtl->stack_realign_needed);
4221 }
4222 }
4223 }
4224
4225 /* Remember if the outgoing parameter requires extra alignment on the
4226 calling function side. */
4227 if (crtl->stack_alignment_needed < boundary)
4228 crtl->stack_alignment_needed = boundary;
4229 if (crtl->preferred_stack_boundary < boundary)
4230 crtl->preferred_stack_boundary = boundary;
4231
4232 if (ARGS_GROW_DOWNWARD)
4233 {
4234 locate->slot_offset.constant = -initial_offset_ptr->constant;
4235 if (initial_offset_ptr->var)
4236 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4237 initial_offset_ptr->var);
4238
4239 {
4240 tree s2 = sizetree;
4241 if (where_pad != PAD_NONE
4242 && (!tree_fits_uhwi_p (sizetree)
4243 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4244 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4245 SUB_PARM_SIZE (locate->slot_offset, s2);
4246 }
4247
4248 locate->slot_offset.constant += part_size_in_regs;
4249
4250 if (!in_regs || reg_parm_stack_space > 0)
4251 pad_to_arg_alignment (&locate->slot_offset, boundary,
4252 &locate->alignment_pad);
4253
4254 locate->size.constant = (-initial_offset_ptr->constant
4255 - locate->slot_offset.constant);
4256 if (initial_offset_ptr->var)
4257 locate->size.var = size_binop (MINUS_EXPR,
4258 size_binop (MINUS_EXPR,
4259 ssize_int (0),
4260 initial_offset_ptr->var),
4261 locate->slot_offset.var);
4262
4263 /* Pad_below needs the pre-rounded size to know how much to pad
4264 below. */
4265 locate->offset = locate->slot_offset;
4266 if (where_pad == PAD_DOWNWARD)
4267 pad_below (&locate->offset, passed_mode, sizetree);
4268
4269 }
4270 else
4271 {
4272 if (!in_regs || reg_parm_stack_space > 0)
4273 pad_to_arg_alignment (initial_offset_ptr, boundary,
4274 &locate->alignment_pad);
4275 locate->slot_offset = *initial_offset_ptr;
4276
4277 #ifdef PUSH_ROUNDING
4278 if (passed_mode != BLKmode)
4279 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4280 #endif
4281
4282 /* Pad_below needs the pre-rounded size to know how much to pad below
4283 so this must be done before rounding up. */
4284 locate->offset = locate->slot_offset;
4285 if (where_pad == PAD_DOWNWARD)
4286 pad_below (&locate->offset, passed_mode, sizetree);
4287
4288 if (where_pad != PAD_NONE
4289 && (!tree_fits_uhwi_p (sizetree)
4290 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4291 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4292
4293 ADD_PARM_SIZE (locate->size, sizetree);
4294
4295 locate->size.constant -= part_size_in_regs;
4296 }
4297
4298 locate->offset.constant
4299 += targetm.calls.function_arg_offset (passed_mode, type);
4300 }
4301
4302 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4303 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4304
4305 static void
pad_to_arg_alignment(struct args_size * offset_ptr,int boundary,struct args_size * alignment_pad)4306 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4307 struct args_size *alignment_pad)
4308 {
4309 tree save_var = NULL_TREE;
4310 poly_int64 save_constant = 0;
4311 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4312 poly_int64 sp_offset = STACK_POINTER_OFFSET;
4313
4314 #ifdef SPARC_STACK_BOUNDARY_HACK
4315 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4316 the real alignment of %sp. However, when it does this, the
4317 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4318 if (SPARC_STACK_BOUNDARY_HACK)
4319 sp_offset = 0;
4320 #endif
4321
4322 if (boundary > PARM_BOUNDARY)
4323 {
4324 save_var = offset_ptr->var;
4325 save_constant = offset_ptr->constant;
4326 }
4327
4328 alignment_pad->var = NULL_TREE;
4329 alignment_pad->constant = 0;
4330
4331 if (boundary > BITS_PER_UNIT)
4332 {
4333 int misalign;
4334 if (offset_ptr->var
4335 || !known_misalignment (offset_ptr->constant + sp_offset,
4336 boundary_in_bytes, &misalign))
4337 {
4338 tree sp_offset_tree = ssize_int (sp_offset);
4339 tree offset = size_binop (PLUS_EXPR,
4340 ARGS_SIZE_TREE (*offset_ptr),
4341 sp_offset_tree);
4342 tree rounded;
4343 if (ARGS_GROW_DOWNWARD)
4344 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4345 else
4346 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4347
4348 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4349 /* ARGS_SIZE_TREE includes constant term. */
4350 offset_ptr->constant = 0;
4351 if (boundary > PARM_BOUNDARY)
4352 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4353 save_var);
4354 }
4355 else
4356 {
4357 if (ARGS_GROW_DOWNWARD)
4358 offset_ptr->constant -= misalign;
4359 else
4360 offset_ptr->constant += -misalign & (boundary_in_bytes - 1);
4361
4362 if (boundary > PARM_BOUNDARY)
4363 alignment_pad->constant = offset_ptr->constant - save_constant;
4364 }
4365 }
4366 }
4367
4368 static void
pad_below(struct args_size * offset_ptr,machine_mode passed_mode,tree sizetree)4369 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4370 {
4371 unsigned int align = PARM_BOUNDARY / BITS_PER_UNIT;
4372 int misalign;
4373 if (passed_mode != BLKmode
4374 && known_misalignment (GET_MODE_SIZE (passed_mode), align, &misalign))
4375 offset_ptr->constant += -misalign & (align - 1);
4376 else
4377 {
4378 if (TREE_CODE (sizetree) != INTEGER_CST
4379 || (TREE_INT_CST_LOW (sizetree) & (align - 1)) != 0)
4380 {
4381 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4382 tree s2 = round_up (sizetree, align);
4383 /* Add it in. */
4384 ADD_PARM_SIZE (*offset_ptr, s2);
4385 SUB_PARM_SIZE (*offset_ptr, sizetree);
4386 }
4387 }
4388 }
4389
4390
4391 /* True if register REGNO was alive at a place where `setjmp' was
4392 called and was set more than once or is an argument. Such regs may
4393 be clobbered by `longjmp'. */
4394
4395 static bool
regno_clobbered_at_setjmp(bitmap setjmp_crosses,int regno)4396 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4397 {
4398 /* There appear to be cases where some local vars never reach the
4399 backend but have bogus regnos. */
4400 if (regno >= max_reg_num ())
4401 return false;
4402
4403 return ((REG_N_SETS (regno) > 1
4404 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4405 regno))
4406 && REGNO_REG_SET_P (setjmp_crosses, regno));
4407 }
4408
4409 /* Walk the tree of blocks describing the binding levels within a
4410 function and warn about variables the might be killed by setjmp or
4411 vfork. This is done after calling flow_analysis before register
4412 allocation since that will clobber the pseudo-regs to hard
4413 regs. */
4414
4415 static void
setjmp_vars_warning(bitmap setjmp_crosses,tree block)4416 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4417 {
4418 tree decl, sub;
4419
4420 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4421 {
4422 if (VAR_P (decl)
4423 && DECL_RTL_SET_P (decl)
4424 && REG_P (DECL_RTL (decl))
4425 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4426 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4427 " %<longjmp%> or %<vfork%>", decl);
4428 }
4429
4430 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4431 setjmp_vars_warning (setjmp_crosses, sub);
4432 }
4433
4434 /* Do the appropriate part of setjmp_vars_warning
4435 but for arguments instead of local variables. */
4436
4437 static void
setjmp_args_warning(bitmap setjmp_crosses)4438 setjmp_args_warning (bitmap setjmp_crosses)
4439 {
4440 tree decl;
4441 for (decl = DECL_ARGUMENTS (current_function_decl);
4442 decl; decl = DECL_CHAIN (decl))
4443 if (DECL_RTL (decl) != 0
4444 && REG_P (DECL_RTL (decl))
4445 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4446 warning (OPT_Wclobbered,
4447 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4448 decl);
4449 }
4450
4451 /* Generate warning messages for variables live across setjmp. */
4452
4453 void
generate_setjmp_warnings(void)4454 generate_setjmp_warnings (void)
4455 {
4456 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4457
4458 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4459 || bitmap_empty_p (setjmp_crosses))
4460 return;
4461
4462 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4463 setjmp_args_warning (setjmp_crosses);
4464 }
4465
4466
4467 /* Reverse the order of elements in the fragment chain T of blocks,
4468 and return the new head of the chain (old last element).
4469 In addition to that clear BLOCK_SAME_RANGE flags when needed
4470 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4471 its super fragment origin. */
4472
4473 static tree
block_fragments_nreverse(tree t)4474 block_fragments_nreverse (tree t)
4475 {
4476 tree prev = 0, block, next, prev_super = 0;
4477 tree super = BLOCK_SUPERCONTEXT (t);
4478 if (BLOCK_FRAGMENT_ORIGIN (super))
4479 super = BLOCK_FRAGMENT_ORIGIN (super);
4480 for (block = t; block; block = next)
4481 {
4482 next = BLOCK_FRAGMENT_CHAIN (block);
4483 BLOCK_FRAGMENT_CHAIN (block) = prev;
4484 if ((prev && !BLOCK_SAME_RANGE (prev))
4485 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4486 != prev_super))
4487 BLOCK_SAME_RANGE (block) = 0;
4488 prev_super = BLOCK_SUPERCONTEXT (block);
4489 BLOCK_SUPERCONTEXT (block) = super;
4490 prev = block;
4491 }
4492 t = BLOCK_FRAGMENT_ORIGIN (t);
4493 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4494 != prev_super)
4495 BLOCK_SAME_RANGE (t) = 0;
4496 BLOCK_SUPERCONTEXT (t) = super;
4497 return prev;
4498 }
4499
4500 /* Reverse the order of elements in the chain T of blocks,
4501 and return the new head of the chain (old last element).
4502 Also do the same on subblocks and reverse the order of elements
4503 in BLOCK_FRAGMENT_CHAIN as well. */
4504
4505 static tree
blocks_nreverse_all(tree t)4506 blocks_nreverse_all (tree t)
4507 {
4508 tree prev = 0, block, next;
4509 for (block = t; block; block = next)
4510 {
4511 next = BLOCK_CHAIN (block);
4512 BLOCK_CHAIN (block) = prev;
4513 if (BLOCK_FRAGMENT_CHAIN (block)
4514 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4515 {
4516 BLOCK_FRAGMENT_CHAIN (block)
4517 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4518 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4519 BLOCK_SAME_RANGE (block) = 0;
4520 }
4521 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4522 prev = block;
4523 }
4524 return prev;
4525 }
4526
4527
4528 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4529 and create duplicate blocks. */
4530 /* ??? Need an option to either create block fragments or to create
4531 abstract origin duplicates of a source block. It really depends
4532 on what optimization has been performed. */
4533
4534 void
reorder_blocks(void)4535 reorder_blocks (void)
4536 {
4537 tree block = DECL_INITIAL (current_function_decl);
4538
4539 if (block == NULL_TREE)
4540 return;
4541
4542 auto_vec<tree, 10> block_stack;
4543
4544 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4545 clear_block_marks (block);
4546
4547 /* Prune the old trees away, so that they don't get in the way. */
4548 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4549 BLOCK_CHAIN (block) = NULL_TREE;
4550
4551 /* Recreate the block tree from the note nesting. */
4552 reorder_blocks_1 (get_insns (), block, &block_stack);
4553 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4554 }
4555
4556 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4557
4558 void
clear_block_marks(tree block)4559 clear_block_marks (tree block)
4560 {
4561 while (block)
4562 {
4563 TREE_ASM_WRITTEN (block) = 0;
4564 clear_block_marks (BLOCK_SUBBLOCKS (block));
4565 block = BLOCK_CHAIN (block);
4566 }
4567 }
4568
4569 static void
reorder_blocks_1(rtx_insn * insns,tree current_block,vec<tree> * p_block_stack)4570 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4571 vec<tree> *p_block_stack)
4572 {
4573 rtx_insn *insn;
4574 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4575
4576 for (insn = insns; insn; insn = NEXT_INSN (insn))
4577 {
4578 if (NOTE_P (insn))
4579 {
4580 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4581 {
4582 tree block = NOTE_BLOCK (insn);
4583 tree origin;
4584
4585 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4586 origin = block;
4587
4588 if (prev_end)
4589 BLOCK_SAME_RANGE (prev_end) = 0;
4590 prev_end = NULL_TREE;
4591
4592 /* If we have seen this block before, that means it now
4593 spans multiple address regions. Create a new fragment. */
4594 if (TREE_ASM_WRITTEN (block))
4595 {
4596 tree new_block = copy_node (block);
4597
4598 BLOCK_SAME_RANGE (new_block) = 0;
4599 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4600 BLOCK_FRAGMENT_CHAIN (new_block)
4601 = BLOCK_FRAGMENT_CHAIN (origin);
4602 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4603
4604 NOTE_BLOCK (insn) = new_block;
4605 block = new_block;
4606 }
4607
4608 if (prev_beg == current_block && prev_beg)
4609 BLOCK_SAME_RANGE (block) = 1;
4610
4611 prev_beg = origin;
4612
4613 BLOCK_SUBBLOCKS (block) = 0;
4614 TREE_ASM_WRITTEN (block) = 1;
4615 /* When there's only one block for the entire function,
4616 current_block == block and we mustn't do this, it
4617 will cause infinite recursion. */
4618 if (block != current_block)
4619 {
4620 tree super;
4621 if (block != origin)
4622 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4623 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4624 (origin))
4625 == current_block);
4626 if (p_block_stack->is_empty ())
4627 super = current_block;
4628 else
4629 {
4630 super = p_block_stack->last ();
4631 gcc_assert (super == current_block
4632 || BLOCK_FRAGMENT_ORIGIN (super)
4633 == current_block);
4634 }
4635 BLOCK_SUPERCONTEXT (block) = super;
4636 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4637 BLOCK_SUBBLOCKS (current_block) = block;
4638 current_block = origin;
4639 }
4640 p_block_stack->safe_push (block);
4641 }
4642 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4643 {
4644 NOTE_BLOCK (insn) = p_block_stack->pop ();
4645 current_block = BLOCK_SUPERCONTEXT (current_block);
4646 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4647 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4648 prev_beg = NULL_TREE;
4649 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4650 ? NOTE_BLOCK (insn) : NULL_TREE;
4651 }
4652 }
4653 else
4654 {
4655 prev_beg = NULL_TREE;
4656 if (prev_end)
4657 BLOCK_SAME_RANGE (prev_end) = 0;
4658 prev_end = NULL_TREE;
4659 }
4660 }
4661 }
4662
4663 /* Reverse the order of elements in the chain T of blocks,
4664 and return the new head of the chain (old last element). */
4665
4666 tree
blocks_nreverse(tree t)4667 blocks_nreverse (tree t)
4668 {
4669 tree prev = 0, block, next;
4670 for (block = t; block; block = next)
4671 {
4672 next = BLOCK_CHAIN (block);
4673 BLOCK_CHAIN (block) = prev;
4674 prev = block;
4675 }
4676 return prev;
4677 }
4678
4679 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4680 by modifying the last node in chain 1 to point to chain 2. */
4681
4682 tree
block_chainon(tree op1,tree op2)4683 block_chainon (tree op1, tree op2)
4684 {
4685 tree t1;
4686
4687 if (!op1)
4688 return op2;
4689 if (!op2)
4690 return op1;
4691
4692 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4693 continue;
4694 BLOCK_CHAIN (t1) = op2;
4695
4696 #ifdef ENABLE_TREE_CHECKING
4697 {
4698 tree t2;
4699 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4700 gcc_assert (t2 != t1);
4701 }
4702 #endif
4703
4704 return op1;
4705 }
4706
4707 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4708 non-NULL, list them all into VECTOR, in a depth-first preorder
4709 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4710 blocks. */
4711
4712 static int
all_blocks(tree block,tree * vector)4713 all_blocks (tree block, tree *vector)
4714 {
4715 int n_blocks = 0;
4716
4717 while (block)
4718 {
4719 TREE_ASM_WRITTEN (block) = 0;
4720
4721 /* Record this block. */
4722 if (vector)
4723 vector[n_blocks] = block;
4724
4725 ++n_blocks;
4726
4727 /* Record the subblocks, and their subblocks... */
4728 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4729 vector ? vector + n_blocks : 0);
4730 block = BLOCK_CHAIN (block);
4731 }
4732
4733 return n_blocks;
4734 }
4735
4736 /* Return a vector containing all the blocks rooted at BLOCK. The
4737 number of elements in the vector is stored in N_BLOCKS_P. The
4738 vector is dynamically allocated; it is the caller's responsibility
4739 to call `free' on the pointer returned. */
4740
4741 static tree *
get_block_vector(tree block,int * n_blocks_p)4742 get_block_vector (tree block, int *n_blocks_p)
4743 {
4744 tree *block_vector;
4745
4746 *n_blocks_p = all_blocks (block, NULL);
4747 block_vector = XNEWVEC (tree, *n_blocks_p);
4748 all_blocks (block, block_vector);
4749
4750 return block_vector;
4751 }
4752
4753 static GTY(()) int next_block_index = 2;
4754
4755 /* Set BLOCK_NUMBER for all the blocks in FN. */
4756
4757 void
number_blocks(tree fn)4758 number_blocks (tree fn)
4759 {
4760 int i;
4761 int n_blocks;
4762 tree *block_vector;
4763
4764 /* For XCOFF debugging output, we start numbering the blocks
4765 from 1 within each function, rather than keeping a running
4766 count. */
4767 #if defined (XCOFF_DEBUGGING_INFO)
4768 if (write_symbols == XCOFF_DEBUG)
4769 next_block_index = 1;
4770 #endif
4771
4772 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4773
4774 /* The top-level BLOCK isn't numbered at all. */
4775 for (i = 1; i < n_blocks; ++i)
4776 /* We number the blocks from two. */
4777 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4778
4779 free (block_vector);
4780
4781 return;
4782 }
4783
4784 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4785
4786 DEBUG_FUNCTION tree
debug_find_var_in_block_tree(tree var,tree block)4787 debug_find_var_in_block_tree (tree var, tree block)
4788 {
4789 tree t;
4790
4791 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4792 if (t == var)
4793 return block;
4794
4795 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4796 {
4797 tree ret = debug_find_var_in_block_tree (var, t);
4798 if (ret)
4799 return ret;
4800 }
4801
4802 return NULL_TREE;
4803 }
4804
4805 /* Keep track of whether we're in a dummy function context. If we are,
4806 we don't want to invoke the set_current_function hook, because we'll
4807 get into trouble if the hook calls target_reinit () recursively or
4808 when the initial initialization is not yet complete. */
4809
4810 static bool in_dummy_function;
4811
4812 /* Invoke the target hook when setting cfun. Update the optimization options
4813 if the function uses different options than the default. */
4814
4815 static void
invoke_set_current_function_hook(tree fndecl)4816 invoke_set_current_function_hook (tree fndecl)
4817 {
4818 if (!in_dummy_function)
4819 {
4820 tree opts = ((fndecl)
4821 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4822 : optimization_default_node);
4823
4824 if (!opts)
4825 opts = optimization_default_node;
4826
4827 /* Change optimization options if needed. */
4828 if (optimization_current_node != opts)
4829 {
4830 optimization_current_node = opts;
4831 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4832 }
4833
4834 targetm.set_current_function (fndecl);
4835 this_fn_optabs = this_target_optabs;
4836
4837 if (opts != optimization_default_node)
4838 {
4839 init_tree_optimization_optabs (opts);
4840 if (TREE_OPTIMIZATION_OPTABS (opts))
4841 this_fn_optabs = (struct target_optabs *)
4842 TREE_OPTIMIZATION_OPTABS (opts);
4843 }
4844 }
4845 }
4846
4847 /* cfun should never be set directly; use this function. */
4848
4849 void
set_cfun(struct function * new_cfun,bool force)4850 set_cfun (struct function *new_cfun, bool force)
4851 {
4852 if (cfun != new_cfun || force)
4853 {
4854 cfun = new_cfun;
4855 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4856 redirect_edge_var_map_empty ();
4857 }
4858 }
4859
4860 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4861
4862 static vec<function *> cfun_stack;
4863
4864 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4865 current_function_decl accordingly. */
4866
4867 void
push_cfun(struct function * new_cfun)4868 push_cfun (struct function *new_cfun)
4869 {
4870 gcc_assert ((!cfun && !current_function_decl)
4871 || (cfun && current_function_decl == cfun->decl));
4872 cfun_stack.safe_push (cfun);
4873 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4874 set_cfun (new_cfun);
4875 }
4876
4877 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4878
4879 void
pop_cfun(void)4880 pop_cfun (void)
4881 {
4882 struct function *new_cfun = cfun_stack.pop ();
4883 /* When in_dummy_function, we do have a cfun but current_function_decl is
4884 NULL. We also allow pushing NULL cfun and subsequently changing
4885 current_function_decl to something else and have both restored by
4886 pop_cfun. */
4887 gcc_checking_assert (in_dummy_function
4888 || !cfun
4889 || current_function_decl == cfun->decl);
4890 set_cfun (new_cfun);
4891 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4892 }
4893
4894 /* Return value of funcdef and increase it. */
4895 int
get_next_funcdef_no(void)4896 get_next_funcdef_no (void)
4897 {
4898 return funcdef_no++;
4899 }
4900
4901 /* Return value of funcdef. */
4902 int
get_last_funcdef_no(void)4903 get_last_funcdef_no (void)
4904 {
4905 return funcdef_no;
4906 }
4907
4908 /* Allocate a function structure for FNDECL and set its contents
4909 to the defaults. Set cfun to the newly-allocated object.
4910 Some of the helper functions invoked during initialization assume
4911 that cfun has already been set. Therefore, assign the new object
4912 directly into cfun and invoke the back end hook explicitly at the
4913 very end, rather than initializing a temporary and calling set_cfun
4914 on it.
4915
4916 ABSTRACT_P is true if this is a function that will never be seen by
4917 the middle-end. Such functions are front-end concepts (like C++
4918 function templates) that do not correspond directly to functions
4919 placed in object files. */
4920
4921 void
allocate_struct_function(tree fndecl,bool abstract_p)4922 allocate_struct_function (tree fndecl, bool abstract_p)
4923 {
4924 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4925
4926 cfun = ggc_cleared_alloc<function> ();
4927
4928 init_eh_for_function ();
4929
4930 if (init_machine_status)
4931 cfun->machine = (*init_machine_status) ();
4932
4933 #ifdef OVERRIDE_ABI_FORMAT
4934 OVERRIDE_ABI_FORMAT (fndecl);
4935 #endif
4936
4937 if (fndecl != NULL_TREE)
4938 {
4939 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4940 cfun->decl = fndecl;
4941 current_function_funcdef_no = get_next_funcdef_no ();
4942 }
4943
4944 invoke_set_current_function_hook (fndecl);
4945
4946 if (fndecl != NULL_TREE)
4947 {
4948 tree result = DECL_RESULT (fndecl);
4949
4950 if (!abstract_p)
4951 {
4952 /* Now that we have activated any function-specific attributes
4953 that might affect layout, particularly vector modes, relayout
4954 each of the parameters and the result. */
4955 relayout_decl (result);
4956 for (tree parm = DECL_ARGUMENTS (fndecl); parm;
4957 parm = DECL_CHAIN (parm))
4958 relayout_decl (parm);
4959
4960 /* Similarly relayout the function decl. */
4961 targetm.target_option.relayout_function (fndecl);
4962 }
4963
4964 if (!abstract_p && aggregate_value_p (result, fndecl))
4965 {
4966 #ifdef PCC_STATIC_STRUCT_RETURN
4967 cfun->returns_pcc_struct = 1;
4968 #endif
4969 cfun->returns_struct = 1;
4970 }
4971
4972 cfun->stdarg = stdarg_p (fntype);
4973
4974 /* Assume all registers in stdarg functions need to be saved. */
4975 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4976 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4977
4978 /* ??? This could be set on a per-function basis by the front-end
4979 but is this worth the hassle? */
4980 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4981 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4982
4983 if (!profile_flag && !flag_instrument_function_entry_exit)
4984 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4985 }
4986
4987 /* Don't enable begin stmt markers if var-tracking at assignments is
4988 disabled. The markers make little sense without the variable
4989 binding annotations among them. */
4990 cfun->debug_nonbind_markers = lang_hooks.emits_begin_stmt
4991 && MAY_HAVE_DEBUG_MARKER_STMTS;
4992 }
4993
4994 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4995 instead of just setting it. */
4996
4997 void
push_struct_function(tree fndecl)4998 push_struct_function (tree fndecl)
4999 {
5000 /* When in_dummy_function we might be in the middle of a pop_cfun and
5001 current_function_decl and cfun may not match. */
5002 gcc_assert (in_dummy_function
5003 || (!cfun && !current_function_decl)
5004 || (cfun && current_function_decl == cfun->decl));
5005 cfun_stack.safe_push (cfun);
5006 current_function_decl = fndecl;
5007 allocate_struct_function (fndecl, false);
5008 }
5009
5010 /* Reset crtl and other non-struct-function variables to defaults as
5011 appropriate for emitting rtl at the start of a function. */
5012
5013 static void
prepare_function_start(void)5014 prepare_function_start (void)
5015 {
5016 gcc_assert (!get_last_insn ());
5017 init_temp_slots ();
5018 init_emit ();
5019 init_varasm_status ();
5020 init_expr ();
5021 default_rtl_profile ();
5022
5023 if (flag_stack_usage_info)
5024 {
5025 cfun->su = ggc_cleared_alloc<stack_usage> ();
5026 cfun->su->static_stack_size = -1;
5027 }
5028
5029 cse_not_expected = ! optimize;
5030
5031 /* Caller save not needed yet. */
5032 caller_save_needed = 0;
5033
5034 /* We haven't done register allocation yet. */
5035 reg_renumber = 0;
5036
5037 /* Indicate that we have not instantiated virtual registers yet. */
5038 virtuals_instantiated = 0;
5039
5040 /* Indicate that we want CONCATs now. */
5041 generating_concat_p = 1;
5042
5043 /* Indicate we have no need of a frame pointer yet. */
5044 frame_pointer_needed = 0;
5045 }
5046
5047 void
push_dummy_function(bool with_decl)5048 push_dummy_function (bool with_decl)
5049 {
5050 tree fn_decl, fn_type, fn_result_decl;
5051
5052 gcc_assert (!in_dummy_function);
5053 in_dummy_function = true;
5054
5055 if (with_decl)
5056 {
5057 fn_type = build_function_type_list (void_type_node, NULL_TREE);
5058 fn_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
5059 fn_type);
5060 fn_result_decl = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
5061 NULL_TREE, void_type_node);
5062 DECL_RESULT (fn_decl) = fn_result_decl;
5063 }
5064 else
5065 fn_decl = NULL_TREE;
5066
5067 push_struct_function (fn_decl);
5068 }
5069
5070 /* Initialize the rtl expansion mechanism so that we can do simple things
5071 like generate sequences. This is used to provide a context during global
5072 initialization of some passes. You must call expand_dummy_function_end
5073 to exit this context. */
5074
5075 void
init_dummy_function_start(void)5076 init_dummy_function_start (void)
5077 {
5078 push_dummy_function (false);
5079 prepare_function_start ();
5080 }
5081
5082 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5083 and initialize static variables for generating RTL for the statements
5084 of the function. */
5085
5086 void
init_function_start(tree subr)5087 init_function_start (tree subr)
5088 {
5089 /* Initialize backend, if needed. */
5090 initialize_rtl ();
5091
5092 prepare_function_start ();
5093 decide_function_section (subr);
5094
5095 /* Warn if this value is an aggregate type,
5096 regardless of which calling convention we are using for it. */
5097 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5098 warning (OPT_Waggregate_return, "function returns an aggregate");
5099 }
5100
5101 /* Expand code to verify the stack_protect_guard. This is invoked at
5102 the end of a function to be protected. */
5103
5104 void
stack_protect_epilogue(void)5105 stack_protect_epilogue (void)
5106 {
5107 tree guard_decl = targetm.stack_protect_guard ();
5108 rtx_code_label *label = gen_label_rtx ();
5109 rtx x, y;
5110 rtx_insn *seq;
5111
5112 x = expand_normal (crtl->stack_protect_guard);
5113 if (guard_decl)
5114 y = expand_normal (guard_decl);
5115 else
5116 y = const0_rtx;
5117
5118 /* Allow the target to compare Y with X without leaking either into
5119 a register. */
5120 if (targetm.have_stack_protect_test ()
5121 && ((seq = targetm.gen_stack_protect_test (x, y, label)) != NULL_RTX))
5122 emit_insn (seq);
5123 else
5124 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
5125
5126 /* The noreturn predictor has been moved to the tree level. The rtl-level
5127 predictors estimate this branch about 20%, which isn't enough to get
5128 things moved out of line. Since this is the only extant case of adding
5129 a noreturn function at the rtl level, it doesn't seem worth doing ought
5130 except adding the prediction by hand. */
5131 rtx_insn *tmp = get_last_insn ();
5132 if (JUMP_P (tmp))
5133 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
5134
5135 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
5136 free_temp_slots ();
5137 emit_label (label);
5138 }
5139
5140 /* Start the RTL for a new function, and set variables used for
5141 emitting RTL.
5142 SUBR is the FUNCTION_DECL node.
5143 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5144 the function's parameters, which must be run at any return statement. */
5145
5146 void
expand_function_start(tree subr)5147 expand_function_start (tree subr)
5148 {
5149 /* Make sure volatile mem refs aren't considered
5150 valid operands of arithmetic insns. */
5151 init_recog_no_volatile ();
5152
5153 crtl->profile
5154 = (profile_flag
5155 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5156
5157 crtl->limit_stack
5158 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
5159
5160 /* Make the label for return statements to jump to. Do not special
5161 case machines with special return instructions -- they will be
5162 handled later during jump, ifcvt, or epilogue creation. */
5163 return_label = gen_label_rtx ();
5164
5165 /* Initialize rtx used to return the value. */
5166 /* Do this before assign_parms so that we copy the struct value address
5167 before any library calls that assign parms might generate. */
5168
5169 /* Decide whether to return the value in memory or in a register. */
5170 tree res = DECL_RESULT (subr);
5171 if (aggregate_value_p (res, subr))
5172 {
5173 /* Returning something that won't go in a register. */
5174 rtx value_address = 0;
5175
5176 #ifdef PCC_STATIC_STRUCT_RETURN
5177 if (cfun->returns_pcc_struct)
5178 {
5179 int size = int_size_in_bytes (TREE_TYPE (res));
5180 value_address = assemble_static_space (size);
5181 }
5182 else
5183 #endif
5184 {
5185 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
5186 /* Expect to be passed the address of a place to store the value.
5187 If it is passed as an argument, assign_parms will take care of
5188 it. */
5189 if (sv)
5190 {
5191 value_address = gen_reg_rtx (Pmode);
5192 emit_move_insn (value_address, sv);
5193 }
5194 }
5195 if (value_address)
5196 {
5197 rtx x = value_address;
5198 if (!DECL_BY_REFERENCE (res))
5199 {
5200 x = gen_rtx_MEM (DECL_MODE (res), x);
5201 set_mem_attributes (x, res, 1);
5202 }
5203 set_parm_rtl (res, x);
5204 }
5205 }
5206 else if (DECL_MODE (res) == VOIDmode)
5207 /* If return mode is void, this decl rtl should not be used. */
5208 set_parm_rtl (res, NULL_RTX);
5209 else
5210 {
5211 /* Compute the return values into a pseudo reg, which we will copy
5212 into the true return register after the cleanups are done. */
5213 tree return_type = TREE_TYPE (res);
5214
5215 /* If we may coalesce this result, make sure it has the expected mode
5216 in case it was promoted. But we need not bother about BLKmode. */
5217 machine_mode promoted_mode
5218 = flag_tree_coalesce_vars && is_gimple_reg (res)
5219 ? promote_ssa_mode (ssa_default_def (cfun, res), NULL)
5220 : BLKmode;
5221
5222 if (promoted_mode != BLKmode)
5223 set_parm_rtl (res, gen_reg_rtx (promoted_mode));
5224 else if (TYPE_MODE (return_type) != BLKmode
5225 && targetm.calls.return_in_msb (return_type))
5226 /* expand_function_end will insert the appropriate padding in
5227 this case. Use the return value's natural (unpadded) mode
5228 within the function proper. */
5229 set_parm_rtl (res, gen_reg_rtx (TYPE_MODE (return_type)));
5230 else
5231 {
5232 /* In order to figure out what mode to use for the pseudo, we
5233 figure out what the mode of the eventual return register will
5234 actually be, and use that. */
5235 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
5236
5237 /* Structures that are returned in registers are not
5238 aggregate_value_p, so we may see a PARALLEL or a REG. */
5239 if (REG_P (hard_reg))
5240 set_parm_rtl (res, gen_reg_rtx (GET_MODE (hard_reg)));
5241 else
5242 {
5243 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5244 set_parm_rtl (res, gen_group_rtx (hard_reg));
5245 }
5246 }
5247
5248 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5249 result to the real return register(s). */
5250 DECL_REGISTER (res) = 1;
5251
5252 if (chkp_function_instrumented_p (current_function_decl))
5253 {
5254 tree return_type = TREE_TYPE (res);
5255 rtx bounds = targetm.calls.chkp_function_value_bounds (return_type,
5256 subr, 1);
5257 SET_DECL_BOUNDS_RTL (res, bounds);
5258 }
5259 }
5260
5261 /* Initialize rtx for parameters and local variables.
5262 In some cases this requires emitting insns. */
5263 assign_parms (subr);
5264
5265 /* If function gets a static chain arg, store it. */
5266 if (cfun->static_chain_decl)
5267 {
5268 tree parm = cfun->static_chain_decl;
5269 rtx local, chain;
5270 rtx_insn *insn;
5271 int unsignedp;
5272
5273 local = gen_reg_rtx (promote_decl_mode (parm, &unsignedp));
5274 chain = targetm.calls.static_chain (current_function_decl, true);
5275
5276 set_decl_incoming_rtl (parm, chain, false);
5277 set_parm_rtl (parm, local);
5278 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5279
5280 if (GET_MODE (local) != GET_MODE (chain))
5281 {
5282 convert_move (local, chain, unsignedp);
5283 insn = get_last_insn ();
5284 }
5285 else
5286 insn = emit_move_insn (local, chain);
5287
5288 /* Mark the register as eliminable, similar to parameters. */
5289 if (MEM_P (chain)
5290 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
5291 set_dst_reg_note (insn, REG_EQUIV, chain, local);
5292
5293 /* If we aren't optimizing, save the static chain onto the stack. */
5294 if (!optimize)
5295 {
5296 tree saved_static_chain_decl
5297 = build_decl (DECL_SOURCE_LOCATION (parm), VAR_DECL,
5298 DECL_NAME (parm), TREE_TYPE (parm));
5299 rtx saved_static_chain_rtx
5300 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5301 SET_DECL_RTL (saved_static_chain_decl, saved_static_chain_rtx);
5302 emit_move_insn (saved_static_chain_rtx, chain);
5303 SET_DECL_VALUE_EXPR (parm, saved_static_chain_decl);
5304 DECL_HAS_VALUE_EXPR_P (parm) = 1;
5305 }
5306 }
5307
5308 /* The following was moved from init_function_start.
5309 The move was supposed to make sdb output more accurate. */
5310 /* Indicate the beginning of the function body,
5311 as opposed to parm setup. */
5312 emit_note (NOTE_INSN_FUNCTION_BEG);
5313
5314 gcc_assert (NOTE_P (get_last_insn ()));
5315
5316 parm_birth_insn = get_last_insn ();
5317
5318 /* If the function receives a non-local goto, then store the
5319 bits we need to restore the frame pointer. */
5320 if (cfun->nonlocal_goto_save_area)
5321 {
5322 tree t_save;
5323 rtx r_save;
5324
5325 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5326 gcc_assert (DECL_RTL_SET_P (var));
5327
5328 t_save = build4 (ARRAY_REF,
5329 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
5330 cfun->nonlocal_goto_save_area,
5331 integer_zero_node, NULL_TREE, NULL_TREE);
5332 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
5333 gcc_assert (GET_MODE (r_save) == Pmode);
5334
5335 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
5336 update_nonlocal_goto_save_area ();
5337 }
5338
5339 if (crtl->profile)
5340 {
5341 #ifdef PROFILE_HOOK
5342 PROFILE_HOOK (current_function_funcdef_no);
5343 #endif
5344 }
5345
5346 /* If we are doing generic stack checking, the probe should go here. */
5347 if (flag_stack_check == GENERIC_STACK_CHECK)
5348 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
5349 }
5350
5351 void
pop_dummy_function(void)5352 pop_dummy_function (void)
5353 {
5354 pop_cfun ();
5355 in_dummy_function = false;
5356 }
5357
5358 /* Undo the effects of init_dummy_function_start. */
5359 void
expand_dummy_function_end(void)5360 expand_dummy_function_end (void)
5361 {
5362 gcc_assert (in_dummy_function);
5363
5364 /* End any sequences that failed to be closed due to syntax errors. */
5365 while (in_sequence_p ())
5366 end_sequence ();
5367
5368 /* Outside function body, can't compute type's actual size
5369 until next function's body starts. */
5370
5371 free_after_parsing (cfun);
5372 free_after_compilation (cfun);
5373 pop_dummy_function ();
5374 }
5375
5376 /* Helper for diddle_return_value. */
5377
5378 void
diddle_return_value_1(void (* doit)(rtx,void *),void * arg,rtx outgoing)5379 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5380 {
5381 if (! outgoing)
5382 return;
5383
5384 if (REG_P (outgoing))
5385 (*doit) (outgoing, arg);
5386 else if (GET_CODE (outgoing) == PARALLEL)
5387 {
5388 int i;
5389
5390 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5391 {
5392 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5393
5394 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5395 (*doit) (x, arg);
5396 }
5397 }
5398 }
5399
5400 /* Call DOIT for each hard register used as a return value from
5401 the current function. */
5402
5403 void
diddle_return_value(void (* doit)(rtx,void *),void * arg)5404 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5405 {
5406 diddle_return_value_1 (doit, arg, crtl->return_bnd);
5407 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5408 }
5409
5410 static void
do_clobber_return_reg(rtx reg,void * arg ATTRIBUTE_UNUSED)5411 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5412 {
5413 emit_clobber (reg);
5414 }
5415
5416 void
clobber_return_register(void)5417 clobber_return_register (void)
5418 {
5419 diddle_return_value (do_clobber_return_reg, NULL);
5420
5421 /* In case we do use pseudo to return value, clobber it too. */
5422 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5423 {
5424 tree decl_result = DECL_RESULT (current_function_decl);
5425 rtx decl_rtl = DECL_RTL (decl_result);
5426 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
5427 {
5428 do_clobber_return_reg (decl_rtl, NULL);
5429 }
5430 }
5431 }
5432
5433 static void
do_use_return_reg(rtx reg,void * arg ATTRIBUTE_UNUSED)5434 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5435 {
5436 emit_use (reg);
5437 }
5438
5439 static void
use_return_register(void)5440 use_return_register (void)
5441 {
5442 diddle_return_value (do_use_return_reg, NULL);
5443 }
5444
5445 /* Set the location of the insn chain starting at INSN to LOC. */
5446
5447 static void
set_insn_locations(rtx_insn * insn,int loc)5448 set_insn_locations (rtx_insn *insn, int loc)
5449 {
5450 while (insn != NULL)
5451 {
5452 if (INSN_P (insn))
5453 INSN_LOCATION (insn) = loc;
5454 insn = NEXT_INSN (insn);
5455 }
5456 }
5457
5458 /* Generate RTL for the end of the current function. */
5459
5460 void
expand_function_end(void)5461 expand_function_end (void)
5462 {
5463 /* If arg_pointer_save_area was referenced only from a nested
5464 function, we will not have initialized it yet. Do that now. */
5465 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
5466 get_arg_pointer_save_area ();
5467
5468 /* If we are doing generic stack checking and this function makes calls,
5469 do a stack probe at the start of the function to ensure we have enough
5470 space for another stack frame. */
5471 if (flag_stack_check == GENERIC_STACK_CHECK)
5472 {
5473 rtx_insn *insn, *seq;
5474
5475 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5476 if (CALL_P (insn))
5477 {
5478 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
5479 start_sequence ();
5480 if (STACK_CHECK_MOVING_SP)
5481 anti_adjust_stack_and_probe (max_frame_size, true);
5482 else
5483 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
5484 seq = get_insns ();
5485 end_sequence ();
5486 set_insn_locations (seq, prologue_location);
5487 emit_insn_before (seq, stack_check_probe_note);
5488 break;
5489 }
5490 }
5491
5492 /* End any sequences that failed to be closed due to syntax errors. */
5493 while (in_sequence_p ())
5494 end_sequence ();
5495
5496 clear_pending_stack_adjust ();
5497 do_pending_stack_adjust ();
5498
5499 /* Output a linenumber for the end of the function.
5500 SDB depended on this. */
5501 set_curr_insn_location (input_location);
5502
5503 /* Before the return label (if any), clobber the return
5504 registers so that they are not propagated live to the rest of
5505 the function. This can only happen with functions that drop
5506 through; if there had been a return statement, there would
5507 have either been a return rtx, or a jump to the return label.
5508
5509 We delay actual code generation after the current_function_value_rtx
5510 is computed. */
5511 rtx_insn *clobber_after = get_last_insn ();
5512
5513 /* Output the label for the actual return from the function. */
5514 emit_label (return_label);
5515
5516 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
5517 {
5518 /* Let except.c know where it should emit the call to unregister
5519 the function context for sjlj exceptions. */
5520 if (flag_exceptions)
5521 sjlj_emit_function_exit_after (get_last_insn ());
5522 }
5523 else
5524 {
5525 /* We want to ensure that instructions that may trap are not
5526 moved into the epilogue by scheduling, because we don't
5527 always emit unwind information for the epilogue. */
5528 if (cfun->can_throw_non_call_exceptions)
5529 emit_insn (gen_blockage ());
5530 }
5531
5532 /* If this is an implementation of throw, do what's necessary to
5533 communicate between __builtin_eh_return and the epilogue. */
5534 expand_eh_return ();
5535
5536 /* If scalar return value was computed in a pseudo-reg, or was a named
5537 return value that got dumped to the stack, copy that to the hard
5538 return register. */
5539 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5540 {
5541 tree decl_result = DECL_RESULT (current_function_decl);
5542 rtx decl_rtl = DECL_RTL (decl_result);
5543
5544 if (REG_P (decl_rtl)
5545 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5546 : DECL_REGISTER (decl_result))
5547 {
5548 rtx real_decl_rtl = crtl->return_rtx;
5549 complex_mode cmode;
5550
5551 /* This should be set in assign_parms. */
5552 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5553
5554 /* If this is a BLKmode structure being returned in registers,
5555 then use the mode computed in expand_return. Note that if
5556 decl_rtl is memory, then its mode may have been changed,
5557 but that crtl->return_rtx has not. */
5558 if (GET_MODE (real_decl_rtl) == BLKmode)
5559 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5560
5561 /* If a non-BLKmode return value should be padded at the least
5562 significant end of the register, shift it left by the appropriate
5563 amount. BLKmode results are handled using the group load/store
5564 machinery. */
5565 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5566 && REG_P (real_decl_rtl)
5567 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5568 {
5569 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5570 REGNO (real_decl_rtl)),
5571 decl_rtl);
5572 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5573 }
5574 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5575 {
5576 /* If expand_function_start has created a PARALLEL for decl_rtl,
5577 move the result to the real return registers. Otherwise, do
5578 a group load from decl_rtl for a named return. */
5579 if (GET_CODE (decl_rtl) == PARALLEL)
5580 emit_group_move (real_decl_rtl, decl_rtl);
5581 else
5582 emit_group_load (real_decl_rtl, decl_rtl,
5583 TREE_TYPE (decl_result),
5584 int_size_in_bytes (TREE_TYPE (decl_result)));
5585 }
5586 /* In the case of complex integer modes smaller than a word, we'll
5587 need to generate some non-trivial bitfield insertions. Do that
5588 on a pseudo and not the hard register. */
5589 else if (GET_CODE (decl_rtl) == CONCAT
5590 && is_complex_int_mode (GET_MODE (decl_rtl), &cmode)
5591 && GET_MODE_BITSIZE (cmode) <= BITS_PER_WORD)
5592 {
5593 int old_generating_concat_p;
5594 rtx tmp;
5595
5596 old_generating_concat_p = generating_concat_p;
5597 generating_concat_p = 0;
5598 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5599 generating_concat_p = old_generating_concat_p;
5600
5601 emit_move_insn (tmp, decl_rtl);
5602 emit_move_insn (real_decl_rtl, tmp);
5603 }
5604 /* If a named return value dumped decl_return to memory, then
5605 we may need to re-do the PROMOTE_MODE signed/unsigned
5606 extension. */
5607 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5608 {
5609 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5610 promote_function_mode (TREE_TYPE (decl_result),
5611 GET_MODE (decl_rtl), &unsignedp,
5612 TREE_TYPE (current_function_decl), 1);
5613
5614 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5615 }
5616 else
5617 emit_move_insn (real_decl_rtl, decl_rtl);
5618 }
5619 }
5620
5621 /* If returning a structure, arrange to return the address of the value
5622 in a place where debuggers expect to find it.
5623
5624 If returning a structure PCC style,
5625 the caller also depends on this value.
5626 And cfun->returns_pcc_struct is not necessarily set. */
5627 if ((cfun->returns_struct || cfun->returns_pcc_struct)
5628 && !targetm.calls.omit_struct_return_reg)
5629 {
5630 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5631 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5632 rtx outgoing;
5633
5634 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5635 type = TREE_TYPE (type);
5636 else
5637 value_address = XEXP (value_address, 0);
5638
5639 outgoing = targetm.calls.function_value (build_pointer_type (type),
5640 current_function_decl, true);
5641
5642 /* Mark this as a function return value so integrate will delete the
5643 assignment and USE below when inlining this function. */
5644 REG_FUNCTION_VALUE_P (outgoing) = 1;
5645
5646 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5647 scalar_int_mode mode = as_a <scalar_int_mode> (GET_MODE (outgoing));
5648 value_address = convert_memory_address (mode, value_address);
5649
5650 emit_move_insn (outgoing, value_address);
5651
5652 /* Show return register used to hold result (in this case the address
5653 of the result. */
5654 crtl->return_rtx = outgoing;
5655 }
5656
5657 /* Emit the actual code to clobber return register. Don't emit
5658 it if clobber_after is a barrier, then the previous basic block
5659 certainly doesn't fall thru into the exit block. */
5660 if (!BARRIER_P (clobber_after))
5661 {
5662 start_sequence ();
5663 clobber_return_register ();
5664 rtx_insn *seq = get_insns ();
5665 end_sequence ();
5666
5667 emit_insn_after (seq, clobber_after);
5668 }
5669
5670 /* Output the label for the naked return from the function. */
5671 if (naked_return_label)
5672 emit_label (naked_return_label);
5673
5674 /* @@@ This is a kludge. We want to ensure that instructions that
5675 may trap are not moved into the epilogue by scheduling, because
5676 we don't always emit unwind information for the epilogue. */
5677 if (cfun->can_throw_non_call_exceptions
5678 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5679 emit_insn (gen_blockage ());
5680
5681 /* If stack protection is enabled for this function, check the guard. */
5682 if (crtl->stack_protect_guard && targetm.stack_protect_runtime_enabled_p ())
5683 stack_protect_epilogue ();
5684
5685 /* If we had calls to alloca, and this machine needs
5686 an accurate stack pointer to exit the function,
5687 insert some code to save and restore the stack pointer. */
5688 if (! EXIT_IGNORE_STACK
5689 && cfun->calls_alloca)
5690 {
5691 rtx tem = 0;
5692
5693 start_sequence ();
5694 emit_stack_save (SAVE_FUNCTION, &tem);
5695 rtx_insn *seq = get_insns ();
5696 end_sequence ();
5697 emit_insn_before (seq, parm_birth_insn);
5698
5699 emit_stack_restore (SAVE_FUNCTION, tem);
5700 }
5701
5702 /* ??? This should no longer be necessary since stupid is no longer with
5703 us, but there are some parts of the compiler (eg reload_combine, and
5704 sh mach_dep_reorg) that still try and compute their own lifetime info
5705 instead of using the general framework. */
5706 use_return_register ();
5707 }
5708
5709 rtx
get_arg_pointer_save_area(void)5710 get_arg_pointer_save_area (void)
5711 {
5712 rtx ret = arg_pointer_save_area;
5713
5714 if (! ret)
5715 {
5716 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5717 arg_pointer_save_area = ret;
5718 }
5719
5720 if (! crtl->arg_pointer_save_area_init)
5721 {
5722 /* Save the arg pointer at the beginning of the function. The
5723 generated stack slot may not be a valid memory address, so we
5724 have to check it and fix it if necessary. */
5725 start_sequence ();
5726 emit_move_insn (validize_mem (copy_rtx (ret)),
5727 crtl->args.internal_arg_pointer);
5728 rtx_insn *seq = get_insns ();
5729 end_sequence ();
5730
5731 push_topmost_sequence ();
5732 emit_insn_after (seq, entry_of_function ());
5733 pop_topmost_sequence ();
5734
5735 crtl->arg_pointer_save_area_init = true;
5736 }
5737
5738 return ret;
5739 }
5740
5741
5742 /* If debugging dumps are requested, dump information about how the
5743 target handled -fstack-check=clash for the prologue.
5744
5745 PROBES describes what if any probes were emitted.
5746
5747 RESIDUALS indicates if the prologue had any residual allocation
5748 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5749
5750 void
dump_stack_clash_frame_info(enum stack_clash_probes probes,bool residuals)5751 dump_stack_clash_frame_info (enum stack_clash_probes probes, bool residuals)
5752 {
5753 if (!dump_file)
5754 return;
5755
5756 switch (probes)
5757 {
5758 case NO_PROBE_NO_FRAME:
5759 fprintf (dump_file,
5760 "Stack clash no probe no stack adjustment in prologue.\n");
5761 break;
5762 case NO_PROBE_SMALL_FRAME:
5763 fprintf (dump_file,
5764 "Stack clash no probe small stack adjustment in prologue.\n");
5765 break;
5766 case PROBE_INLINE:
5767 fprintf (dump_file, "Stack clash inline probes in prologue.\n");
5768 break;
5769 case PROBE_LOOP:
5770 fprintf (dump_file, "Stack clash probe loop in prologue.\n");
5771 break;
5772 }
5773
5774 if (residuals)
5775 fprintf (dump_file, "Stack clash residual allocation in prologue.\n");
5776 else
5777 fprintf (dump_file, "Stack clash no residual allocation in prologue.\n");
5778
5779 if (frame_pointer_needed)
5780 fprintf (dump_file, "Stack clash frame pointer needed.\n");
5781 else
5782 fprintf (dump_file, "Stack clash no frame pointer needed.\n");
5783
5784 if (TREE_THIS_VOLATILE (cfun->decl))
5785 fprintf (dump_file,
5786 "Stack clash noreturn prologue, assuming no implicit"
5787 " probes in caller.\n");
5788 else
5789 fprintf (dump_file,
5790 "Stack clash not noreturn prologue.\n");
5791 }
5792
5793 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5794 for the first time. */
5795
5796 static void
record_insns(rtx_insn * insns,rtx end,hash_table<insn_cache_hasher> ** hashp)5797 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5798 {
5799 rtx_insn *tmp;
5800 hash_table<insn_cache_hasher> *hash = *hashp;
5801
5802 if (hash == NULL)
5803 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5804
5805 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5806 {
5807 rtx *slot = hash->find_slot (tmp, INSERT);
5808 gcc_assert (*slot == NULL);
5809 *slot = tmp;
5810 }
5811 }
5812
5813 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5814 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5815 insn, then record COPY as well. */
5816
5817 void
maybe_copy_prologue_epilogue_insn(rtx insn,rtx copy)5818 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5819 {
5820 hash_table<insn_cache_hasher> *hash;
5821 rtx *slot;
5822
5823 hash = epilogue_insn_hash;
5824 if (!hash || !hash->find (insn))
5825 {
5826 hash = prologue_insn_hash;
5827 if (!hash || !hash->find (insn))
5828 return;
5829 }
5830
5831 slot = hash->find_slot (copy, INSERT);
5832 gcc_assert (*slot == NULL);
5833 *slot = copy;
5834 }
5835
5836 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5837 we can be running after reorg, SEQUENCE rtl is possible. */
5838
5839 static bool
contains(const rtx_insn * insn,hash_table<insn_cache_hasher> * hash)5840 contains (const rtx_insn *insn, hash_table<insn_cache_hasher> *hash)
5841 {
5842 if (hash == NULL)
5843 return false;
5844
5845 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5846 {
5847 rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn));
5848 int i;
5849 for (i = seq->len () - 1; i >= 0; i--)
5850 if (hash->find (seq->element (i)))
5851 return true;
5852 return false;
5853 }
5854
5855 return hash->find (const_cast<rtx_insn *> (insn)) != NULL;
5856 }
5857
5858 int
prologue_contains(const rtx_insn * insn)5859 prologue_contains (const rtx_insn *insn)
5860 {
5861 return contains (insn, prologue_insn_hash);
5862 }
5863
5864 int
epilogue_contains(const rtx_insn * insn)5865 epilogue_contains (const rtx_insn *insn)
5866 {
5867 return contains (insn, epilogue_insn_hash);
5868 }
5869
5870 int
prologue_epilogue_contains(const rtx_insn * insn)5871 prologue_epilogue_contains (const rtx_insn *insn)
5872 {
5873 if (contains (insn, prologue_insn_hash))
5874 return 1;
5875 if (contains (insn, epilogue_insn_hash))
5876 return 1;
5877 return 0;
5878 }
5879
5880 void
record_prologue_seq(rtx_insn * seq)5881 record_prologue_seq (rtx_insn *seq)
5882 {
5883 record_insns (seq, NULL, &prologue_insn_hash);
5884 }
5885
5886 void
record_epilogue_seq(rtx_insn * seq)5887 record_epilogue_seq (rtx_insn *seq)
5888 {
5889 record_insns (seq, NULL, &epilogue_insn_hash);
5890 }
5891
5892 /* Set JUMP_LABEL for a return insn. */
5893
5894 void
set_return_jump_label(rtx_insn * returnjump)5895 set_return_jump_label (rtx_insn *returnjump)
5896 {
5897 rtx pat = PATTERN (returnjump);
5898 if (GET_CODE (pat) == PARALLEL)
5899 pat = XVECEXP (pat, 0, 0);
5900 if (ANY_RETURN_P (pat))
5901 JUMP_LABEL (returnjump) = pat;
5902 else
5903 JUMP_LABEL (returnjump) = ret_rtx;
5904 }
5905
5906 /* Return a sequence to be used as the split prologue for the current
5907 function, or NULL. */
5908
5909 static rtx_insn *
make_split_prologue_seq(void)5910 make_split_prologue_seq (void)
5911 {
5912 if (!flag_split_stack
5913 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl)))
5914 return NULL;
5915
5916 start_sequence ();
5917 emit_insn (targetm.gen_split_stack_prologue ());
5918 rtx_insn *seq = get_insns ();
5919 end_sequence ();
5920
5921 record_insns (seq, NULL, &prologue_insn_hash);
5922 set_insn_locations (seq, prologue_location);
5923
5924 return seq;
5925 }
5926
5927 /* Return a sequence to be used as the prologue for the current function,
5928 or NULL. */
5929
5930 static rtx_insn *
make_prologue_seq(void)5931 make_prologue_seq (void)
5932 {
5933 if (!targetm.have_prologue ())
5934 return NULL;
5935
5936 start_sequence ();
5937 rtx_insn *seq = targetm.gen_prologue ();
5938 emit_insn (seq);
5939
5940 /* Insert an explicit USE for the frame pointer
5941 if the profiling is on and the frame pointer is required. */
5942 if (crtl->profile && frame_pointer_needed)
5943 emit_use (hard_frame_pointer_rtx);
5944
5945 /* Retain a map of the prologue insns. */
5946 record_insns (seq, NULL, &prologue_insn_hash);
5947 emit_note (NOTE_INSN_PROLOGUE_END);
5948
5949 /* Ensure that instructions are not moved into the prologue when
5950 profiling is on. The call to the profiling routine can be
5951 emitted within the live range of a call-clobbered register. */
5952 if (!targetm.profile_before_prologue () && crtl->profile)
5953 emit_insn (gen_blockage ());
5954
5955 seq = get_insns ();
5956 end_sequence ();
5957 set_insn_locations (seq, prologue_location);
5958
5959 return seq;
5960 }
5961
5962 /* Return a sequence to be used as the epilogue for the current function,
5963 or NULL. */
5964
5965 static rtx_insn *
make_epilogue_seq(void)5966 make_epilogue_seq (void)
5967 {
5968 if (!targetm.have_epilogue ())
5969 return NULL;
5970
5971 start_sequence ();
5972 emit_note (NOTE_INSN_EPILOGUE_BEG);
5973 rtx_insn *seq = targetm.gen_epilogue ();
5974 if (seq)
5975 emit_jump_insn (seq);
5976
5977 /* Retain a map of the epilogue insns. */
5978 record_insns (seq, NULL, &epilogue_insn_hash);
5979 set_insn_locations (seq, epilogue_location);
5980
5981 seq = get_insns ();
5982 rtx_insn *returnjump = get_last_insn ();
5983 end_sequence ();
5984
5985 if (JUMP_P (returnjump))
5986 set_return_jump_label (returnjump);
5987
5988 return seq;
5989 }
5990
5991
5992 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5993 this into place with notes indicating where the prologue ends and where
5994 the epilogue begins. Update the basic block information when possible.
5995
5996 Notes on epilogue placement:
5997 There are several kinds of edges to the exit block:
5998 * a single fallthru edge from LAST_BB
5999 * possibly, edges from blocks containing sibcalls
6000 * possibly, fake edges from infinite loops
6001
6002 The epilogue is always emitted on the fallthru edge from the last basic
6003 block in the function, LAST_BB, into the exit block.
6004
6005 If LAST_BB is empty except for a label, it is the target of every
6006 other basic block in the function that ends in a return. If a
6007 target has a return or simple_return pattern (possibly with
6008 conditional variants), these basic blocks can be changed so that a
6009 return insn is emitted into them, and their target is adjusted to
6010 the real exit block.
6011
6012 Notes on shrink wrapping: We implement a fairly conservative
6013 version of shrink-wrapping rather than the textbook one. We only
6014 generate a single prologue and a single epilogue. This is
6015 sufficient to catch a number of interesting cases involving early
6016 exits.
6017
6018 First, we identify the blocks that require the prologue to occur before
6019 them. These are the ones that modify a call-saved register, or reference
6020 any of the stack or frame pointer registers. To simplify things, we then
6021 mark everything reachable from these blocks as also requiring a prologue.
6022 This takes care of loops automatically, and avoids the need to examine
6023 whether MEMs reference the frame, since it is sufficient to check for
6024 occurrences of the stack or frame pointer.
6025
6026 We then compute the set of blocks for which the need for a prologue
6027 is anticipatable (borrowing terminology from the shrink-wrapping
6028 description in Muchnick's book). These are the blocks which either
6029 require a prologue themselves, or those that have only successors
6030 where the prologue is anticipatable. The prologue needs to be
6031 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
6032 is not. For the moment, we ensure that only one such edge exists.
6033
6034 The epilogue is placed as described above, but we make a
6035 distinction between inserting return and simple_return patterns
6036 when modifying other blocks that end in a return. Blocks that end
6037 in a sibcall omit the sibcall_epilogue if the block is not in
6038 ANTIC. */
6039
6040 void
thread_prologue_and_epilogue_insns(void)6041 thread_prologue_and_epilogue_insns (void)
6042 {
6043 df_analyze ();
6044
6045 /* Can't deal with multiple successors of the entry block at the
6046 moment. Function should always have at least one entry
6047 point. */
6048 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
6049
6050 edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
6051 edge orig_entry_edge = entry_edge;
6052
6053 rtx_insn *split_prologue_seq = make_split_prologue_seq ();
6054 rtx_insn *prologue_seq = make_prologue_seq ();
6055 rtx_insn *epilogue_seq = make_epilogue_seq ();
6056
6057 /* Try to perform a kind of shrink-wrapping, making sure the
6058 prologue/epilogue is emitted only around those parts of the
6059 function that require it. */
6060 try_shrink_wrapping (&entry_edge, prologue_seq);
6061
6062 /* If the target can handle splitting the prologue/epilogue into separate
6063 components, try to shrink-wrap these components separately. */
6064 try_shrink_wrapping_separate (entry_edge->dest);
6065
6066 /* If that did anything for any component we now need the generate the
6067 "main" prologue again. Because some targets require some of these
6068 to be called in a specific order (i386 requires the split prologue
6069 to be first, for example), we create all three sequences again here.
6070 If this does not work for some target, that target should not enable
6071 separate shrink-wrapping. */
6072 if (crtl->shrink_wrapped_separate)
6073 {
6074 split_prologue_seq = make_split_prologue_seq ();
6075 prologue_seq = make_prologue_seq ();
6076 epilogue_seq = make_epilogue_seq ();
6077 }
6078
6079 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
6080
6081 /* A small fib -- epilogue is not yet completed, but we wish to re-use
6082 this marker for the splits of EH_RETURN patterns, and nothing else
6083 uses the flag in the meantime. */
6084 epilogue_completed = 1;
6085
6086 /* Find non-fallthru edges that end with EH_RETURN instructions. On
6087 some targets, these get split to a special version of the epilogue
6088 code. In order to be able to properly annotate these with unwind
6089 info, try to split them now. If we get a valid split, drop an
6090 EPILOGUE_BEG note and mark the insns as epilogue insns. */
6091 edge e;
6092 edge_iterator ei;
6093 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6094 {
6095 rtx_insn *prev, *last, *trial;
6096
6097 if (e->flags & EDGE_FALLTHRU)
6098 continue;
6099 last = BB_END (e->src);
6100 if (!eh_returnjump_p (last))
6101 continue;
6102
6103 prev = PREV_INSN (last);
6104 trial = try_split (PATTERN (last), last, 1);
6105 if (trial == last)
6106 continue;
6107
6108 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
6109 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
6110 }
6111
6112 edge exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6113
6114 if (exit_fallthru_edge)
6115 {
6116 if (epilogue_seq)
6117 {
6118 insert_insn_on_edge (epilogue_seq, exit_fallthru_edge);
6119 commit_edge_insertions ();
6120
6121 /* The epilogue insns we inserted may cause the exit edge to no longer
6122 be fallthru. */
6123 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6124 {
6125 if (((e->flags & EDGE_FALLTHRU) != 0)
6126 && returnjump_p (BB_END (e->src)))
6127 e->flags &= ~EDGE_FALLTHRU;
6128 }
6129 }
6130 else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
6131 {
6132 /* We have a fall-through edge to the exit block, the source is not
6133 at the end of the function, and there will be an assembler epilogue
6134 at the end of the function.
6135 We can't use force_nonfallthru here, because that would try to
6136 use return. Inserting a jump 'by hand' is extremely messy, so
6137 we take advantage of cfg_layout_finalize using
6138 fixup_fallthru_exit_predecessor. */
6139 cfg_layout_initialize (0);
6140 basic_block cur_bb;
6141 FOR_EACH_BB_FN (cur_bb, cfun)
6142 if (cur_bb->index >= NUM_FIXED_BLOCKS
6143 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
6144 cur_bb->aux = cur_bb->next_bb;
6145 cfg_layout_finalize ();
6146 }
6147 }
6148
6149 /* Insert the prologue. */
6150
6151 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
6152
6153 if (split_prologue_seq || prologue_seq)
6154 {
6155 rtx_insn *split_prologue_insn = split_prologue_seq;
6156 if (split_prologue_seq)
6157 {
6158 while (split_prologue_insn && !NONDEBUG_INSN_P (split_prologue_insn))
6159 split_prologue_insn = NEXT_INSN (split_prologue_insn);
6160 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
6161 }
6162
6163 rtx_insn *prologue_insn = prologue_seq;
6164 if (prologue_seq)
6165 {
6166 while (prologue_insn && !NONDEBUG_INSN_P (prologue_insn))
6167 prologue_insn = NEXT_INSN (prologue_insn);
6168 insert_insn_on_edge (prologue_seq, entry_edge);
6169 }
6170
6171 commit_edge_insertions ();
6172
6173 /* Look for basic blocks within the prologue insns. */
6174 if (split_prologue_insn
6175 && BLOCK_FOR_INSN (split_prologue_insn) == NULL)
6176 split_prologue_insn = NULL;
6177 if (prologue_insn
6178 && BLOCK_FOR_INSN (prologue_insn) == NULL)
6179 prologue_insn = NULL;
6180 if (split_prologue_insn || prologue_insn)
6181 {
6182 auto_sbitmap blocks (last_basic_block_for_fn (cfun));
6183 bitmap_clear (blocks);
6184 if (split_prologue_insn)
6185 bitmap_set_bit (blocks,
6186 BLOCK_FOR_INSN (split_prologue_insn)->index);
6187 if (prologue_insn)
6188 bitmap_set_bit (blocks, BLOCK_FOR_INSN (prologue_insn)->index);
6189 find_many_sub_basic_blocks (blocks);
6190 }
6191 }
6192
6193 default_rtl_profile ();
6194
6195 /* Emit sibling epilogues before any sibling call sites. */
6196 for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6197 (e = ei_safe_edge (ei));
6198 ei_next (&ei))
6199 {
6200 /* Skip those already handled, the ones that run without prologue. */
6201 if (e->flags & EDGE_IGNORE)
6202 {
6203 e->flags &= ~EDGE_IGNORE;
6204 continue;
6205 }
6206
6207 rtx_insn *insn = BB_END (e->src);
6208
6209 if (!(CALL_P (insn) && SIBLING_CALL_P (insn)))
6210 continue;
6211
6212 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6213 {
6214 start_sequence ();
6215 emit_note (NOTE_INSN_EPILOGUE_BEG);
6216 emit_insn (ep_seq);
6217 rtx_insn *seq = get_insns ();
6218 end_sequence ();
6219
6220 /* Retain a map of the epilogue insns. Used in life analysis to
6221 avoid getting rid of sibcall epilogue insns. Do this before we
6222 actually emit the sequence. */
6223 record_insns (seq, NULL, &epilogue_insn_hash);
6224 set_insn_locations (seq, epilogue_location);
6225
6226 emit_insn_before (seq, insn);
6227 }
6228 }
6229
6230 if (epilogue_seq)
6231 {
6232 rtx_insn *insn, *next;
6233
6234 /* Similarly, move any line notes that appear after the epilogue.
6235 There is no need, however, to be quite so anal about the existence
6236 of such a note. Also possibly move
6237 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6238 info generation. */
6239 for (insn = epilogue_seq; insn; insn = next)
6240 {
6241 next = NEXT_INSN (insn);
6242 if (NOTE_P (insn)
6243 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6244 reorder_insns (insn, insn, PREV_INSN (epilogue_seq));
6245 }
6246 }
6247
6248 /* Threading the prologue and epilogue changes the artificial refs
6249 in the entry and exit blocks. */
6250 epilogue_completed = 1;
6251 df_update_entry_exit_and_calls ();
6252 }
6253
6254 /* Reposition the prologue-end and epilogue-begin notes after
6255 instruction scheduling. */
6256
6257 void
reposition_prologue_and_epilogue_notes(void)6258 reposition_prologue_and_epilogue_notes (void)
6259 {
6260 if (!targetm.have_prologue ()
6261 && !targetm.have_epilogue ()
6262 && !targetm.have_sibcall_epilogue ())
6263 return;
6264
6265 /* Since the hash table is created on demand, the fact that it is
6266 non-null is a signal that it is non-empty. */
6267 if (prologue_insn_hash != NULL)
6268 {
6269 size_t len = prologue_insn_hash->elements ();
6270 rtx_insn *insn, *last = NULL, *note = NULL;
6271
6272 /* Scan from the beginning until we reach the last prologue insn. */
6273 /* ??? While we do have the CFG intact, there are two problems:
6274 (1) The prologue can contain loops (typically probing the stack),
6275 which means that the end of the prologue isn't in the first bb.
6276 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6277 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6278 {
6279 if (NOTE_P (insn))
6280 {
6281 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6282 note = insn;
6283 }
6284 else if (contains (insn, prologue_insn_hash))
6285 {
6286 last = insn;
6287 if (--len == 0)
6288 break;
6289 }
6290 }
6291
6292 if (last)
6293 {
6294 if (note == NULL)
6295 {
6296 /* Scan forward looking for the PROLOGUE_END note. It should
6297 be right at the beginning of the block, possibly with other
6298 insn notes that got moved there. */
6299 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6300 {
6301 if (NOTE_P (note)
6302 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6303 break;
6304 }
6305 }
6306
6307 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6308 if (LABEL_P (last))
6309 last = NEXT_INSN (last);
6310 reorder_insns (note, note, last);
6311 }
6312 }
6313
6314 if (epilogue_insn_hash != NULL)
6315 {
6316 edge_iterator ei;
6317 edge e;
6318
6319 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6320 {
6321 rtx_insn *insn, *first = NULL, *note = NULL;
6322 basic_block bb = e->src;
6323
6324 /* Scan from the beginning until we reach the first epilogue insn. */
6325 FOR_BB_INSNS (bb, insn)
6326 {
6327 if (NOTE_P (insn))
6328 {
6329 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6330 {
6331 note = insn;
6332 if (first != NULL)
6333 break;
6334 }
6335 }
6336 else if (first == NULL && contains (insn, epilogue_insn_hash))
6337 {
6338 first = insn;
6339 if (note != NULL)
6340 break;
6341 }
6342 }
6343
6344 if (note)
6345 {
6346 /* If the function has a single basic block, and no real
6347 epilogue insns (e.g. sibcall with no cleanup), the
6348 epilogue note can get scheduled before the prologue
6349 note. If we have frame related prologue insns, having
6350 them scanned during the epilogue will result in a crash.
6351 In this case re-order the epilogue note to just before
6352 the last insn in the block. */
6353 if (first == NULL)
6354 first = BB_END (bb);
6355
6356 if (PREV_INSN (first) != note)
6357 reorder_insns (note, note, PREV_INSN (first));
6358 }
6359 }
6360 }
6361 }
6362
6363 /* Returns the name of function declared by FNDECL. */
6364 const char *
fndecl_name(tree fndecl)6365 fndecl_name (tree fndecl)
6366 {
6367 if (fndecl == NULL)
6368 return "(nofn)";
6369 return lang_hooks.decl_printable_name (fndecl, 1);
6370 }
6371
6372 /* Returns the name of function FN. */
6373 const char *
function_name(struct function * fn)6374 function_name (struct function *fn)
6375 {
6376 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6377 return fndecl_name (fndecl);
6378 }
6379
6380 /* Returns the name of the current function. */
6381 const char *
current_function_name(void)6382 current_function_name (void)
6383 {
6384 return function_name (cfun);
6385 }
6386
6387
6388 static unsigned int
rest_of_handle_check_leaf_regs(void)6389 rest_of_handle_check_leaf_regs (void)
6390 {
6391 #ifdef LEAF_REGISTERS
6392 crtl->uses_only_leaf_regs
6393 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6394 #endif
6395 return 0;
6396 }
6397
6398 /* Insert a TYPE into the used types hash table of CFUN. */
6399
6400 static void
used_types_insert_helper(tree type,struct function * func)6401 used_types_insert_helper (tree type, struct function *func)
6402 {
6403 if (type != NULL && func != NULL)
6404 {
6405 if (func->used_types_hash == NULL)
6406 func->used_types_hash = hash_set<tree>::create_ggc (37);
6407
6408 func->used_types_hash->add (type);
6409 }
6410 }
6411
6412 /* Given a type, insert it into the used hash table in cfun. */
6413 void
used_types_insert(tree t)6414 used_types_insert (tree t)
6415 {
6416 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6417 if (TYPE_NAME (t))
6418 break;
6419 else
6420 t = TREE_TYPE (t);
6421 if (TREE_CODE (t) == ERROR_MARK)
6422 return;
6423 if (TYPE_NAME (t) == NULL_TREE
6424 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6425 t = TYPE_MAIN_VARIANT (t);
6426 if (debug_info_level > DINFO_LEVEL_NONE)
6427 {
6428 if (cfun)
6429 used_types_insert_helper (t, cfun);
6430 else
6431 {
6432 /* So this might be a type referenced by a global variable.
6433 Record that type so that we can later decide to emit its
6434 debug information. */
6435 vec_safe_push (types_used_by_cur_var_decl, t);
6436 }
6437 }
6438 }
6439
6440 /* Helper to Hash a struct types_used_by_vars_entry. */
6441
6442 static hashval_t
hash_types_used_by_vars_entry(const struct types_used_by_vars_entry * entry)6443 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6444 {
6445 gcc_assert (entry && entry->var_decl && entry->type);
6446
6447 return iterative_hash_object (entry->type,
6448 iterative_hash_object (entry->var_decl, 0));
6449 }
6450
6451 /* Hash function of the types_used_by_vars_entry hash table. */
6452
6453 hashval_t
hash(types_used_by_vars_entry * entry)6454 used_type_hasher::hash (types_used_by_vars_entry *entry)
6455 {
6456 return hash_types_used_by_vars_entry (entry);
6457 }
6458
6459 /*Equality function of the types_used_by_vars_entry hash table. */
6460
6461 bool
equal(types_used_by_vars_entry * e1,types_used_by_vars_entry * e2)6462 used_type_hasher::equal (types_used_by_vars_entry *e1,
6463 types_used_by_vars_entry *e2)
6464 {
6465 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6466 }
6467
6468 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6469
6470 void
types_used_by_var_decl_insert(tree type,tree var_decl)6471 types_used_by_var_decl_insert (tree type, tree var_decl)
6472 {
6473 if (type != NULL && var_decl != NULL)
6474 {
6475 types_used_by_vars_entry **slot;
6476 struct types_used_by_vars_entry e;
6477 e.var_decl = var_decl;
6478 e.type = type;
6479 if (types_used_by_vars_hash == NULL)
6480 types_used_by_vars_hash
6481 = hash_table<used_type_hasher>::create_ggc (37);
6482
6483 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6484 if (*slot == NULL)
6485 {
6486 struct types_used_by_vars_entry *entry;
6487 entry = ggc_alloc<types_used_by_vars_entry> ();
6488 entry->type = type;
6489 entry->var_decl = var_decl;
6490 *slot = entry;
6491 }
6492 }
6493 }
6494
6495 namespace {
6496
6497 const pass_data pass_data_leaf_regs =
6498 {
6499 RTL_PASS, /* type */
6500 "*leaf_regs", /* name */
6501 OPTGROUP_NONE, /* optinfo_flags */
6502 TV_NONE, /* tv_id */
6503 0, /* properties_required */
6504 0, /* properties_provided */
6505 0, /* properties_destroyed */
6506 0, /* todo_flags_start */
6507 0, /* todo_flags_finish */
6508 };
6509
6510 class pass_leaf_regs : public rtl_opt_pass
6511 {
6512 public:
pass_leaf_regs(gcc::context * ctxt)6513 pass_leaf_regs (gcc::context *ctxt)
6514 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6515 {}
6516
6517 /* opt_pass methods: */
execute(function *)6518 virtual unsigned int execute (function *)
6519 {
6520 return rest_of_handle_check_leaf_regs ();
6521 }
6522
6523 }; // class pass_leaf_regs
6524
6525 } // anon namespace
6526
6527 rtl_opt_pass *
make_pass_leaf_regs(gcc::context * ctxt)6528 make_pass_leaf_regs (gcc::context *ctxt)
6529 {
6530 return new pass_leaf_regs (ctxt);
6531 }
6532
6533 static unsigned int
rest_of_handle_thread_prologue_and_epilogue(void)6534 rest_of_handle_thread_prologue_and_epilogue (void)
6535 {
6536 /* prepare_shrink_wrap is sensitive to the block structure of the control
6537 flow graph, so clean it up first. */
6538 if (optimize)
6539 cleanup_cfg (0);
6540
6541 /* On some machines, the prologue and epilogue code, or parts thereof,
6542 can be represented as RTL. Doing so lets us schedule insns between
6543 it and the rest of the code and also allows delayed branch
6544 scheduling to operate in the epilogue. */
6545 thread_prologue_and_epilogue_insns ();
6546
6547 /* Some non-cold blocks may now be only reachable from cold blocks.
6548 Fix that up. */
6549 fixup_partitions ();
6550
6551 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6552 see PR57320. */
6553 cleanup_cfg (optimize ? CLEANUP_EXPENSIVE : 0);
6554
6555 /* The stack usage info is finalized during prologue expansion. */
6556 if (flag_stack_usage_info)
6557 output_stack_usage ();
6558
6559 return 0;
6560 }
6561
6562 namespace {
6563
6564 const pass_data pass_data_thread_prologue_and_epilogue =
6565 {
6566 RTL_PASS, /* type */
6567 "pro_and_epilogue", /* name */
6568 OPTGROUP_NONE, /* optinfo_flags */
6569 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6570 0, /* properties_required */
6571 0, /* properties_provided */
6572 0, /* properties_destroyed */
6573 0, /* todo_flags_start */
6574 ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
6575 };
6576
6577 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6578 {
6579 public:
pass_thread_prologue_and_epilogue(gcc::context * ctxt)6580 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6581 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6582 {}
6583
6584 /* opt_pass methods: */
execute(function *)6585 virtual unsigned int execute (function *)
6586 {
6587 return rest_of_handle_thread_prologue_and_epilogue ();
6588 }
6589
6590 }; // class pass_thread_prologue_and_epilogue
6591
6592 } // anon namespace
6593
6594 rtl_opt_pass *
make_pass_thread_prologue_and_epilogue(gcc::context * ctxt)6595 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6596 {
6597 return new pass_thread_prologue_and_epilogue (ctxt);
6598 }
6599
6600
6601 /* This mini-pass fixes fall-out from SSA in asm statements that have
6602 in-out constraints. Say you start with
6603
6604 orig = inout;
6605 asm ("": "+mr" (inout));
6606 use (orig);
6607
6608 which is transformed very early to use explicit output and match operands:
6609
6610 orig = inout;
6611 asm ("": "=mr" (inout) : "0" (inout));
6612 use (orig);
6613
6614 Or, after SSA and copyprop,
6615
6616 asm ("": "=mr" (inout_2) : "0" (inout_1));
6617 use (inout_1);
6618
6619 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6620 they represent two separate values, so they will get different pseudo
6621 registers during expansion. Then, since the two operands need to match
6622 per the constraints, but use different pseudo registers, reload can
6623 only register a reload for these operands. But reloads can only be
6624 satisfied by hardregs, not by memory, so we need a register for this
6625 reload, just because we are presented with non-matching operands.
6626 So, even though we allow memory for this operand, no memory can be
6627 used for it, just because the two operands don't match. This can
6628 cause reload failures on register-starved targets.
6629
6630 So it's a symptom of reload not being able to use memory for reloads
6631 or, alternatively it's also a symptom of both operands not coming into
6632 reload as matching (in which case the pseudo could go to memory just
6633 fine, as the alternative allows it, and no reload would be necessary).
6634 We fix the latter problem here, by transforming
6635
6636 asm ("": "=mr" (inout_2) : "0" (inout_1));
6637
6638 back to
6639
6640 inout_2 = inout_1;
6641 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6642
6643 static void
match_asm_constraints_1(rtx_insn * insn,rtx * p_sets,int noutputs)6644 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
6645 {
6646 int i;
6647 bool changed = false;
6648 rtx op = SET_SRC (p_sets[0]);
6649 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6650 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6651 bool *output_matched = XALLOCAVEC (bool, noutputs);
6652
6653 memset (output_matched, 0, noutputs * sizeof (bool));
6654 for (i = 0; i < ninputs; i++)
6655 {
6656 rtx input, output;
6657 rtx_insn *insns;
6658 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6659 char *end;
6660 int match, j;
6661
6662 if (*constraint == '%')
6663 constraint++;
6664
6665 match = strtoul (constraint, &end, 10);
6666 if (end == constraint)
6667 continue;
6668
6669 gcc_assert (match < noutputs);
6670 output = SET_DEST (p_sets[match]);
6671 input = RTVEC_ELT (inputs, i);
6672 /* Only do the transformation for pseudos. */
6673 if (! REG_P (output)
6674 || rtx_equal_p (output, input)
6675 || !(REG_P (input) || SUBREG_P (input)
6676 || MEM_P (input) || CONSTANT_P (input))
6677 || !general_operand (input, GET_MODE (output)))
6678 continue;
6679
6680 /* We can't do anything if the output is also used as input,
6681 as we're going to overwrite it. */
6682 for (j = 0; j < ninputs; j++)
6683 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6684 break;
6685 if (j != ninputs)
6686 continue;
6687
6688 /* Avoid changing the same input several times. For
6689 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6690 only change in once (to out1), rather than changing it
6691 first to out1 and afterwards to out2. */
6692 if (i > 0)
6693 {
6694 for (j = 0; j < noutputs; j++)
6695 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6696 break;
6697 if (j != noutputs)
6698 continue;
6699 }
6700 output_matched[match] = true;
6701
6702 start_sequence ();
6703 emit_move_insn (output, copy_rtx (input));
6704 insns = get_insns ();
6705 end_sequence ();
6706 emit_insn_before (insns, insn);
6707
6708 /* Now replace all mentions of the input with output. We can't
6709 just replace the occurrence in inputs[i], as the register might
6710 also be used in some other input (or even in an address of an
6711 output), which would mean possibly increasing the number of
6712 inputs by one (namely 'output' in addition), which might pose
6713 a too complicated problem for reload to solve. E.g. this situation:
6714
6715 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6716
6717 Here 'input' is used in two occurrences as input (once for the
6718 input operand, once for the address in the second output operand).
6719 If we would replace only the occurrence of the input operand (to
6720 make the matching) we would be left with this:
6721
6722 output = input
6723 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6724
6725 Now we suddenly have two different input values (containing the same
6726 value, but different pseudos) where we formerly had only one.
6727 With more complicated asms this might lead to reload failures
6728 which wouldn't have happen without this pass. So, iterate over
6729 all operands and replace all occurrences of the register used. */
6730 for (j = 0; j < noutputs; j++)
6731 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6732 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6733 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6734 input, output);
6735 for (j = 0; j < ninputs; j++)
6736 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6737 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6738 input, output);
6739
6740 changed = true;
6741 }
6742
6743 if (changed)
6744 df_insn_rescan (insn);
6745 }
6746
6747 /* Add the decl D to the local_decls list of FUN. */
6748
6749 void
add_local_decl(struct function * fun,tree d)6750 add_local_decl (struct function *fun, tree d)
6751 {
6752 gcc_assert (VAR_P (d));
6753 vec_safe_push (fun->local_decls, d);
6754 }
6755
6756 namespace {
6757
6758 const pass_data pass_data_match_asm_constraints =
6759 {
6760 RTL_PASS, /* type */
6761 "asmcons", /* name */
6762 OPTGROUP_NONE, /* optinfo_flags */
6763 TV_NONE, /* tv_id */
6764 0, /* properties_required */
6765 0, /* properties_provided */
6766 0, /* properties_destroyed */
6767 0, /* todo_flags_start */
6768 0, /* todo_flags_finish */
6769 };
6770
6771 class pass_match_asm_constraints : public rtl_opt_pass
6772 {
6773 public:
pass_match_asm_constraints(gcc::context * ctxt)6774 pass_match_asm_constraints (gcc::context *ctxt)
6775 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6776 {}
6777
6778 /* opt_pass methods: */
6779 virtual unsigned int execute (function *);
6780
6781 }; // class pass_match_asm_constraints
6782
6783 unsigned
execute(function * fun)6784 pass_match_asm_constraints::execute (function *fun)
6785 {
6786 basic_block bb;
6787 rtx_insn *insn;
6788 rtx pat, *p_sets;
6789 int noutputs;
6790
6791 if (!crtl->has_asm_statement)
6792 return 0;
6793
6794 df_set_flags (DF_DEFER_INSN_RESCAN);
6795 FOR_EACH_BB_FN (bb, fun)
6796 {
6797 FOR_BB_INSNS (bb, insn)
6798 {
6799 if (!INSN_P (insn))
6800 continue;
6801
6802 pat = PATTERN (insn);
6803 if (GET_CODE (pat) == PARALLEL)
6804 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6805 else if (GET_CODE (pat) == SET)
6806 p_sets = &PATTERN (insn), noutputs = 1;
6807 else
6808 continue;
6809
6810 if (GET_CODE (*p_sets) == SET
6811 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6812 match_asm_constraints_1 (insn, p_sets, noutputs);
6813 }
6814 }
6815
6816 return TODO_df_finish;
6817 }
6818
6819 } // anon namespace
6820
6821 rtl_opt_pass *
make_pass_match_asm_constraints(gcc::context * ctxt)6822 make_pass_match_asm_constraints (gcc::context *ctxt)
6823 {
6824 return new pass_match_asm_constraints (ctxt);
6825 }
6826
6827
6828 #include "gt-function.h"
6829