Use function_arg_info for TARGET_ARG_PARTIAL_BYTES
[gcc.git] / gcc / function.c
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2019 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20 /* This file handles the generation of rtl code from tree structure
21 at the level of the function as a whole.
22 It creates the rtl expressions for parameters and auto variables
23 and has full responsibility for allocating stack slots.
24
25 `expand_function_start' is called at the beginning of a function,
26 before the function body is parsed, and `expand_function_end' is
27 called after parsing the body.
28
29 Call `assign_stack_local' to allocate a stack slot for a local variable.
30 This is usually done during the RTL generation for the function body,
31 but it can also be done in the reload pass when a pseudo-register does
32 not get a hard register. */
33
34 #include "config.h"
35 #include "system.h"
36 #include "coretypes.h"
37 #include "backend.h"
38 #include "target.h"
39 #include "rtl.h"
40 #include "tree.h"
41 #include "gimple-expr.h"
42 #include "cfghooks.h"
43 #include "df.h"
44 #include "memmodel.h"
45 #include "tm_p.h"
46 #include "stringpool.h"
47 #include "expmed.h"
48 #include "optabs.h"
49 #include "regs.h"
50 #include "emit-rtl.h"
51 #include "recog.h"
52 #include "rtl-error.h"
53 #include "alias.h"
54 #include "fold-const.h"
55 #include "stor-layout.h"
56 #include "varasm.h"
57 #include "except.h"
58 #include "dojump.h"
59 #include "explow.h"
60 #include "calls.h"
61 #include "expr.h"
62 #include "optabs-tree.h"
63 #include "output.h"
64 #include "langhooks.h"
65 #include "common/common-target.h"
66 #include "gimplify.h"
67 #include "tree-pass.h"
68 #include "cfgrtl.h"
69 #include "cfganal.h"
70 #include "cfgbuild.h"
71 #include "cfgcleanup.h"
72 #include "cfgexpand.h"
73 #include "shrink-wrap.h"
74 #include "toplev.h"
75 #include "rtl-iter.h"
76 #include "tree-dfa.h"
77 #include "tree-ssa.h"
78 #include "stringpool.h"
79 #include "attribs.h"
80 #include "gimple.h"
81 #include "options.h"
82
83 /* So we can assign to cfun in this file. */
84 #undef cfun
85
86 #ifndef STACK_ALIGNMENT_NEEDED
87 #define STACK_ALIGNMENT_NEEDED 1
88 #endif
89
90 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
91
92 /* Round a value to the lowest integer less than it that is a multiple of
93 the required alignment. Avoid using division in case the value is
94 negative. Assume the alignment is a power of two. */
95 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
96
97 /* Similar, but round to the next highest integer that meets the
98 alignment. */
99 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
100
101 /* Nonzero once virtual register instantiation has been done.
102 assign_stack_local uses frame_pointer_rtx when this is nonzero.
103 calls.c:emit_library_call_value_1 uses it to set up
104 post-instantiation libcalls. */
105 int virtuals_instantiated;
106
107 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
108 static GTY(()) int funcdef_no;
109
110 /* These variables hold pointers to functions to create and destroy
111 target specific, per-function data structures. */
112 struct machine_function * (*init_machine_status) (void);
113
114 /* The currently compiled function. */
115 struct function *cfun = 0;
116
117 /* These hashes record the prologue and epilogue insns. */
118
119 struct insn_cache_hasher : ggc_cache_ptr_hash<rtx_def>
120 {
121 static hashval_t hash (rtx x) { return htab_hash_pointer (x); }
122 static bool equal (rtx a, rtx b) { return a == b; }
123 };
124
125 static GTY((cache))
126 hash_table<insn_cache_hasher> *prologue_insn_hash;
127 static GTY((cache))
128 hash_table<insn_cache_hasher> *epilogue_insn_hash;
129 \f
130
131 hash_table<used_type_hasher> *types_used_by_vars_hash = NULL;
132 vec<tree, va_gc> *types_used_by_cur_var_decl;
133
134 /* Forward declarations. */
135
136 static class temp_slot *find_temp_slot_from_address (rtx);
137 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
138 static void pad_below (struct args_size *, machine_mode, tree);
139 static void reorder_blocks_1 (rtx_insn *, tree, vec<tree> *);
140 static int all_blocks (tree, tree *);
141 static tree *get_block_vector (tree, int *);
142 extern tree debug_find_var_in_block_tree (tree, tree);
143 /* We always define `record_insns' even if it's not used so that we
144 can always export `prologue_epilogue_contains'. */
145 static void record_insns (rtx_insn *, rtx, hash_table<insn_cache_hasher> **)
146 ATTRIBUTE_UNUSED;
147 static bool contains (const rtx_insn *, hash_table<insn_cache_hasher> *);
148 static void prepare_function_start (void);
149 static void do_clobber_return_reg (rtx, void *);
150 static void do_use_return_reg (rtx, void *);
151
152 \f
153 /* Stack of nested functions. */
154 /* Keep track of the cfun stack. */
155
156 static vec<function *> function_context_stack;
157
158 /* Save the current context for compilation of a nested function.
159 This is called from language-specific code. */
160
161 void
162 push_function_context (void)
163 {
164 if (cfun == 0)
165 allocate_struct_function (NULL, false);
166
167 function_context_stack.safe_push (cfun);
168 set_cfun (NULL);
169 }
170
171 /* Restore the last saved context, at the end of a nested function.
172 This function is called from language-specific code. */
173
174 void
175 pop_function_context (void)
176 {
177 struct function *p = function_context_stack.pop ();
178 set_cfun (p);
179 current_function_decl = p->decl;
180
181 /* Reset variables that have known state during rtx generation. */
182 virtuals_instantiated = 0;
183 generating_concat_p = 1;
184 }
185
186 /* Clear out all parts of the state in F that can safely be discarded
187 after the function has been parsed, but not compiled, to let
188 garbage collection reclaim the memory. */
189
190 void
191 free_after_parsing (struct function *f)
192 {
193 f->language = 0;
194 }
195
196 /* Clear out all parts of the state in F that can safely be discarded
197 after the function has been compiled, to let garbage collection
198 reclaim the memory. */
199
200 void
201 free_after_compilation (struct function *f)
202 {
203 prologue_insn_hash = NULL;
204 epilogue_insn_hash = NULL;
205
206 free (crtl->emit.regno_pointer_align);
207
208 memset (crtl, 0, sizeof (struct rtl_data));
209 f->eh = NULL;
210 f->machine = NULL;
211 f->cfg = NULL;
212 f->curr_properties &= ~PROP_cfg;
213
214 regno_reg_rtx = NULL;
215 }
216 \f
217 /* Return size needed for stack frame based on slots so far allocated.
218 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
219 the caller may have to do that. */
220
221 poly_int64
222 get_frame_size (void)
223 {
224 if (FRAME_GROWS_DOWNWARD)
225 return -frame_offset;
226 else
227 return frame_offset;
228 }
229
230 /* Issue an error message and return TRUE if frame OFFSET overflows in
231 the signed target pointer arithmetics for function FUNC. Otherwise
232 return FALSE. */
233
234 bool
235 frame_offset_overflow (poly_int64 offset, tree func)
236 {
237 poly_uint64 size = FRAME_GROWS_DOWNWARD ? -offset : offset;
238 unsigned HOST_WIDE_INT limit
239 = ((HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (Pmode) - 1))
240 /* Leave room for the fixed part of the frame. */
241 - 64 * UNITS_PER_WORD);
242
243 if (!coeffs_in_range_p (size, 0U, limit))
244 {
245 unsigned HOST_WIDE_INT hwisize;
246 if (size.is_constant (&hwisize))
247 error_at (DECL_SOURCE_LOCATION (func),
248 "total size of local objects %wu exceeds maximum %wu",
249 hwisize, limit);
250 else
251 error_at (DECL_SOURCE_LOCATION (func),
252 "total size of local objects exceeds maximum %wu",
253 limit);
254 return true;
255 }
256
257 return false;
258 }
259
260 /* Return the minimum spill slot alignment for a register of mode MODE. */
261
262 unsigned int
263 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED)
264 {
265 return STACK_SLOT_ALIGNMENT (NULL_TREE, mode, GET_MODE_ALIGNMENT (mode));
266 }
267
268 /* Return stack slot alignment in bits for TYPE and MODE. */
269
270 static unsigned int
271 get_stack_local_alignment (tree type, machine_mode mode)
272 {
273 unsigned int alignment;
274
275 if (mode == BLKmode)
276 alignment = BIGGEST_ALIGNMENT;
277 else
278 alignment = GET_MODE_ALIGNMENT (mode);
279
280 /* Allow the frond-end to (possibly) increase the alignment of this
281 stack slot. */
282 if (! type)
283 type = lang_hooks.types.type_for_mode (mode, 0);
284
285 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
286 }
287
288 /* Determine whether it is possible to fit a stack slot of size SIZE and
289 alignment ALIGNMENT into an area in the stack frame that starts at
290 frame offset START and has a length of LENGTH. If so, store the frame
291 offset to be used for the stack slot in *POFFSET and return true;
292 return false otherwise. This function will extend the frame size when
293 given a start/length pair that lies at the end of the frame. */
294
295 static bool
296 try_fit_stack_local (poly_int64 start, poly_int64 length,
297 poly_int64 size, unsigned int alignment,
298 poly_int64_pod *poffset)
299 {
300 poly_int64 this_frame_offset;
301 int frame_off, frame_alignment, frame_phase;
302
303 /* Calculate how many bytes the start of local variables is off from
304 stack alignment. */
305 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
306 frame_off = targetm.starting_frame_offset () % frame_alignment;
307 frame_phase = frame_off ? frame_alignment - frame_off : 0;
308
309 /* Round the frame offset to the specified alignment. */
310
311 if (FRAME_GROWS_DOWNWARD)
312 this_frame_offset
313 = (aligned_lower_bound (start + length - size - frame_phase, alignment)
314 + frame_phase);
315 else
316 this_frame_offset
317 = aligned_upper_bound (start - frame_phase, alignment) + frame_phase;
318
319 /* See if it fits. If this space is at the edge of the frame,
320 consider extending the frame to make it fit. Our caller relies on
321 this when allocating a new slot. */
322 if (maybe_lt (this_frame_offset, start))
323 {
324 if (known_eq (frame_offset, start))
325 frame_offset = this_frame_offset;
326 else
327 return false;
328 }
329 else if (maybe_gt (this_frame_offset + size, start + length))
330 {
331 if (known_eq (frame_offset, start + length))
332 frame_offset = this_frame_offset + size;
333 else
334 return false;
335 }
336
337 *poffset = this_frame_offset;
338 return true;
339 }
340
341 /* Create a new frame_space structure describing free space in the stack
342 frame beginning at START and ending at END, and chain it into the
343 function's frame_space_list. */
344
345 static void
346 add_frame_space (poly_int64 start, poly_int64 end)
347 {
348 class frame_space *space = ggc_alloc<frame_space> ();
349 space->next = crtl->frame_space_list;
350 crtl->frame_space_list = space;
351 space->start = start;
352 space->length = end - start;
353 }
354
355 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
356 with machine mode MODE.
357
358 ALIGN controls the amount of alignment for the address of the slot:
359 0 means according to MODE,
360 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
361 -2 means use BITS_PER_UNIT,
362 positive specifies alignment boundary in bits.
363
364 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
365 alignment and ASLK_RECORD_PAD bit set if we should remember
366 extra space we allocated for alignment purposes. When we are
367 called from assign_stack_temp_for_type, it is not set so we don't
368 track the same stack slot in two independent lists.
369
370 We do not round to stack_boundary here. */
371
372 rtx
373 assign_stack_local_1 (machine_mode mode, poly_int64 size,
374 int align, int kind)
375 {
376 rtx x, addr;
377 poly_int64 bigend_correction = 0;
378 poly_int64 slot_offset = 0, old_frame_offset;
379 unsigned int alignment, alignment_in_bits;
380
381 if (align == 0)
382 {
383 alignment = get_stack_local_alignment (NULL, mode);
384 alignment /= BITS_PER_UNIT;
385 }
386 else if (align == -1)
387 {
388 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
389 size = aligned_upper_bound (size, alignment);
390 }
391 else if (align == -2)
392 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
393 else
394 alignment = align / BITS_PER_UNIT;
395
396 alignment_in_bits = alignment * BITS_PER_UNIT;
397
398 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
399 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
400 {
401 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
402 alignment = MAX_SUPPORTED_STACK_ALIGNMENT / BITS_PER_UNIT;
403 }
404
405 if (SUPPORTS_STACK_ALIGNMENT)
406 {
407 if (crtl->stack_alignment_estimated < alignment_in_bits)
408 {
409 if (!crtl->stack_realign_processed)
410 crtl->stack_alignment_estimated = alignment_in_bits;
411 else
412 {
413 /* If stack is realigned and stack alignment value
414 hasn't been finalized, it is OK not to increase
415 stack_alignment_estimated. The bigger alignment
416 requirement is recorded in stack_alignment_needed
417 below. */
418 gcc_assert (!crtl->stack_realign_finalized);
419 if (!crtl->stack_realign_needed)
420 {
421 /* It is OK to reduce the alignment as long as the
422 requested size is 0 or the estimated stack
423 alignment >= mode alignment. */
424 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
425 || known_eq (size, 0)
426 || (crtl->stack_alignment_estimated
427 >= GET_MODE_ALIGNMENT (mode)));
428 alignment_in_bits = crtl->stack_alignment_estimated;
429 alignment = alignment_in_bits / BITS_PER_UNIT;
430 }
431 }
432 }
433 }
434
435 if (crtl->stack_alignment_needed < alignment_in_bits)
436 crtl->stack_alignment_needed = alignment_in_bits;
437 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
438 crtl->max_used_stack_slot_alignment = alignment_in_bits;
439
440 if (mode != BLKmode || maybe_ne (size, 0))
441 {
442 if (kind & ASLK_RECORD_PAD)
443 {
444 class frame_space **psp;
445
446 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
447 {
448 class frame_space *space = *psp;
449 if (!try_fit_stack_local (space->start, space->length, size,
450 alignment, &slot_offset))
451 continue;
452 *psp = space->next;
453 if (known_gt (slot_offset, space->start))
454 add_frame_space (space->start, slot_offset);
455 if (known_lt (slot_offset + size, space->start + space->length))
456 add_frame_space (slot_offset + size,
457 space->start + space->length);
458 goto found_space;
459 }
460 }
461 }
462 else if (!STACK_ALIGNMENT_NEEDED)
463 {
464 slot_offset = frame_offset;
465 goto found_space;
466 }
467
468 old_frame_offset = frame_offset;
469
470 if (FRAME_GROWS_DOWNWARD)
471 {
472 frame_offset -= size;
473 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
474
475 if (kind & ASLK_RECORD_PAD)
476 {
477 if (known_gt (slot_offset, frame_offset))
478 add_frame_space (frame_offset, slot_offset);
479 if (known_lt (slot_offset + size, old_frame_offset))
480 add_frame_space (slot_offset + size, old_frame_offset);
481 }
482 }
483 else
484 {
485 frame_offset += size;
486 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
487
488 if (kind & ASLK_RECORD_PAD)
489 {
490 if (known_gt (slot_offset, old_frame_offset))
491 add_frame_space (old_frame_offset, slot_offset);
492 if (known_lt (slot_offset + size, frame_offset))
493 add_frame_space (slot_offset + size, frame_offset);
494 }
495 }
496
497 found_space:
498 /* On a big-endian machine, if we are allocating more space than we will use,
499 use the least significant bytes of those that are allocated. */
500 if (mode != BLKmode)
501 {
502 /* The slot size can sometimes be smaller than the mode size;
503 e.g. the rs6000 port allocates slots with a vector mode
504 that have the size of only one element. However, the slot
505 size must always be ordered wrt to the mode size, in the
506 same way as for a subreg. */
507 gcc_checking_assert (ordered_p (GET_MODE_SIZE (mode), size));
508 if (BYTES_BIG_ENDIAN && maybe_lt (GET_MODE_SIZE (mode), size))
509 bigend_correction = size - GET_MODE_SIZE (mode);
510 }
511
512 /* If we have already instantiated virtual registers, return the actual
513 address relative to the frame pointer. */
514 if (virtuals_instantiated)
515 addr = plus_constant (Pmode, frame_pointer_rtx,
516 trunc_int_for_mode
517 (slot_offset + bigend_correction
518 + targetm.starting_frame_offset (), Pmode));
519 else
520 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
521 trunc_int_for_mode
522 (slot_offset + bigend_correction,
523 Pmode));
524
525 x = gen_rtx_MEM (mode, addr);
526 set_mem_align (x, alignment_in_bits);
527 MEM_NOTRAP_P (x) = 1;
528
529 vec_safe_push (stack_slot_list, x);
530
531 if (frame_offset_overflow (frame_offset, current_function_decl))
532 frame_offset = 0;
533
534 return x;
535 }
536
537 /* Wrap up assign_stack_local_1 with last parameter as false. */
538
539 rtx
540 assign_stack_local (machine_mode mode, poly_int64 size, int align)
541 {
542 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
543 }
544 \f
545 /* In order to evaluate some expressions, such as function calls returning
546 structures in memory, we need to temporarily allocate stack locations.
547 We record each allocated temporary in the following structure.
548
549 Associated with each temporary slot is a nesting level. When we pop up
550 one level, all temporaries associated with the previous level are freed.
551 Normally, all temporaries are freed after the execution of the statement
552 in which they were created. However, if we are inside a ({...}) grouping,
553 the result may be in a temporary and hence must be preserved. If the
554 result could be in a temporary, we preserve it if we can determine which
555 one it is in. If we cannot determine which temporary may contain the
556 result, all temporaries are preserved. A temporary is preserved by
557 pretending it was allocated at the previous nesting level. */
558
559 class GTY(()) temp_slot {
560 public:
561 /* Points to next temporary slot. */
562 class temp_slot *next;
563 /* Points to previous temporary slot. */
564 class temp_slot *prev;
565 /* The rtx to used to reference the slot. */
566 rtx slot;
567 /* The size, in units, of the slot. */
568 poly_int64 size;
569 /* The type of the object in the slot, or zero if it doesn't correspond
570 to a type. We use this to determine whether a slot can be reused.
571 It can be reused if objects of the type of the new slot will always
572 conflict with objects of the type of the old slot. */
573 tree type;
574 /* The alignment (in bits) of the slot. */
575 unsigned int align;
576 /* Nonzero if this temporary is currently in use. */
577 char in_use;
578 /* Nesting level at which this slot is being used. */
579 int level;
580 /* The offset of the slot from the frame_pointer, including extra space
581 for alignment. This info is for combine_temp_slots. */
582 poly_int64 base_offset;
583 /* The size of the slot, including extra space for alignment. This
584 info is for combine_temp_slots. */
585 poly_int64 full_size;
586 };
587
588 /* Entry for the below hash table. */
589 struct GTY((for_user)) temp_slot_address_entry {
590 hashval_t hash;
591 rtx address;
592 class temp_slot *temp_slot;
593 };
594
595 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
596 {
597 static hashval_t hash (temp_slot_address_entry *);
598 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
599 };
600
601 /* A table of addresses that represent a stack slot. The table is a mapping
602 from address RTXen to a temp slot. */
603 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
604 static size_t n_temp_slots_in_use;
605
606 /* Removes temporary slot TEMP from LIST. */
607
608 static void
609 cut_slot_from_list (class temp_slot *temp, class temp_slot **list)
610 {
611 if (temp->next)
612 temp->next->prev = temp->prev;
613 if (temp->prev)
614 temp->prev->next = temp->next;
615 else
616 *list = temp->next;
617
618 temp->prev = temp->next = NULL;
619 }
620
621 /* Inserts temporary slot TEMP to LIST. */
622
623 static void
624 insert_slot_to_list (class temp_slot *temp, class temp_slot **list)
625 {
626 temp->next = *list;
627 if (*list)
628 (*list)->prev = temp;
629 temp->prev = NULL;
630 *list = temp;
631 }
632
633 /* Returns the list of used temp slots at LEVEL. */
634
635 static class temp_slot **
636 temp_slots_at_level (int level)
637 {
638 if (level >= (int) vec_safe_length (used_temp_slots))
639 vec_safe_grow_cleared (used_temp_slots, level + 1);
640
641 return &(*used_temp_slots)[level];
642 }
643
644 /* Returns the maximal temporary slot level. */
645
646 static int
647 max_slot_level (void)
648 {
649 if (!used_temp_slots)
650 return -1;
651
652 return used_temp_slots->length () - 1;
653 }
654
655 /* Moves temporary slot TEMP to LEVEL. */
656
657 static void
658 move_slot_to_level (class temp_slot *temp, int level)
659 {
660 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
661 insert_slot_to_list (temp, temp_slots_at_level (level));
662 temp->level = level;
663 }
664
665 /* Make temporary slot TEMP available. */
666
667 static void
668 make_slot_available (class temp_slot *temp)
669 {
670 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
671 insert_slot_to_list (temp, &avail_temp_slots);
672 temp->in_use = 0;
673 temp->level = -1;
674 n_temp_slots_in_use--;
675 }
676
677 /* Compute the hash value for an address -> temp slot mapping.
678 The value is cached on the mapping entry. */
679 static hashval_t
680 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
681 {
682 int do_not_record = 0;
683 return hash_rtx (t->address, GET_MODE (t->address),
684 &do_not_record, NULL, false);
685 }
686
687 /* Return the hash value for an address -> temp slot mapping. */
688 hashval_t
689 temp_address_hasher::hash (temp_slot_address_entry *t)
690 {
691 return t->hash;
692 }
693
694 /* Compare two address -> temp slot mapping entries. */
695 bool
696 temp_address_hasher::equal (temp_slot_address_entry *t1,
697 temp_slot_address_entry *t2)
698 {
699 return exp_equiv_p (t1->address, t2->address, 0, true);
700 }
701
702 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
703 static void
704 insert_temp_slot_address (rtx address, class temp_slot *temp_slot)
705 {
706 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
707 t->address = copy_rtx (address);
708 t->temp_slot = temp_slot;
709 t->hash = temp_slot_address_compute_hash (t);
710 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
711 }
712
713 /* Remove an address -> temp slot mapping entry if the temp slot is
714 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
715 int
716 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
717 {
718 const struct temp_slot_address_entry *t = *slot;
719 if (! t->temp_slot->in_use)
720 temp_slot_address_table->clear_slot (slot);
721 return 1;
722 }
723
724 /* Remove all mappings of addresses to unused temp slots. */
725 static void
726 remove_unused_temp_slot_addresses (void)
727 {
728 /* Use quicker clearing if there aren't any active temp slots. */
729 if (n_temp_slots_in_use)
730 temp_slot_address_table->traverse
731 <void *, remove_unused_temp_slot_addresses_1> (NULL);
732 else
733 temp_slot_address_table->empty ();
734 }
735
736 /* Find the temp slot corresponding to the object at address X. */
737
738 static class temp_slot *
739 find_temp_slot_from_address (rtx x)
740 {
741 class temp_slot *p;
742 struct temp_slot_address_entry tmp, *t;
743
744 /* First try the easy way:
745 See if X exists in the address -> temp slot mapping. */
746 tmp.address = x;
747 tmp.temp_slot = NULL;
748 tmp.hash = temp_slot_address_compute_hash (&tmp);
749 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
750 if (t)
751 return t->temp_slot;
752
753 /* If we have a sum involving a register, see if it points to a temp
754 slot. */
755 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
756 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
757 return p;
758 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
759 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
760 return p;
761
762 /* Last resort: Address is a virtual stack var address. */
763 poly_int64 offset;
764 if (strip_offset (x, &offset) == virtual_stack_vars_rtx)
765 {
766 int i;
767 for (i = max_slot_level (); i >= 0; i--)
768 for (p = *temp_slots_at_level (i); p; p = p->next)
769 if (known_in_range_p (offset, p->base_offset, p->full_size))
770 return p;
771 }
772
773 return NULL;
774 }
775 \f
776 /* Allocate a temporary stack slot and record it for possible later
777 reuse.
778
779 MODE is the machine mode to be given to the returned rtx.
780
781 SIZE is the size in units of the space required. We do no rounding here
782 since assign_stack_local will do any required rounding.
783
784 TYPE is the type that will be used for the stack slot. */
785
786 rtx
787 assign_stack_temp_for_type (machine_mode mode, poly_int64 size, tree type)
788 {
789 unsigned int align;
790 class temp_slot *p, *best_p = 0, *selected = NULL, **pp;
791 rtx slot;
792
793 gcc_assert (known_size_p (size));
794
795 align = get_stack_local_alignment (type, mode);
796
797 /* Try to find an available, already-allocated temporary of the proper
798 mode which meets the size and alignment requirements. Choose the
799 smallest one with the closest alignment.
800
801 If assign_stack_temp is called outside of the tree->rtl expansion,
802 we cannot reuse the stack slots (that may still refer to
803 VIRTUAL_STACK_VARS_REGNUM). */
804 if (!virtuals_instantiated)
805 {
806 for (p = avail_temp_slots; p; p = p->next)
807 {
808 if (p->align >= align
809 && known_ge (p->size, size)
810 && GET_MODE (p->slot) == mode
811 && objects_must_conflict_p (p->type, type)
812 && (best_p == 0
813 || (known_eq (best_p->size, p->size)
814 ? best_p->align > p->align
815 : known_ge (best_p->size, p->size))))
816 {
817 if (p->align == align && known_eq (p->size, size))
818 {
819 selected = p;
820 cut_slot_from_list (selected, &avail_temp_slots);
821 best_p = 0;
822 break;
823 }
824 best_p = p;
825 }
826 }
827 }
828
829 /* Make our best, if any, the one to use. */
830 if (best_p)
831 {
832 selected = best_p;
833 cut_slot_from_list (selected, &avail_temp_slots);
834
835 /* If there are enough aligned bytes left over, make them into a new
836 temp_slot so that the extra bytes don't get wasted. Do this only
837 for BLKmode slots, so that we can be sure of the alignment. */
838 if (GET_MODE (best_p->slot) == BLKmode)
839 {
840 int alignment = best_p->align / BITS_PER_UNIT;
841 poly_int64 rounded_size = aligned_upper_bound (size, alignment);
842
843 if (known_ge (best_p->size - rounded_size, alignment))
844 {
845 p = ggc_alloc<temp_slot> ();
846 p->in_use = 0;
847 p->size = best_p->size - rounded_size;
848 p->base_offset = best_p->base_offset + rounded_size;
849 p->full_size = best_p->full_size - rounded_size;
850 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
851 p->align = best_p->align;
852 p->type = best_p->type;
853 insert_slot_to_list (p, &avail_temp_slots);
854
855 vec_safe_push (stack_slot_list, p->slot);
856
857 best_p->size = rounded_size;
858 best_p->full_size = rounded_size;
859 }
860 }
861 }
862
863 /* If we still didn't find one, make a new temporary. */
864 if (selected == 0)
865 {
866 poly_int64 frame_offset_old = frame_offset;
867
868 p = ggc_alloc<temp_slot> ();
869
870 /* We are passing an explicit alignment request to assign_stack_local.
871 One side effect of that is assign_stack_local will not round SIZE
872 to ensure the frame offset remains suitably aligned.
873
874 So for requests which depended on the rounding of SIZE, we go ahead
875 and round it now. We also make sure ALIGNMENT is at least
876 BIGGEST_ALIGNMENT. */
877 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
878 p->slot = assign_stack_local_1 (mode,
879 (mode == BLKmode
880 ? aligned_upper_bound (size,
881 (int) align
882 / BITS_PER_UNIT)
883 : size),
884 align, 0);
885
886 p->align = align;
887
888 /* The following slot size computation is necessary because we don't
889 know the actual size of the temporary slot until assign_stack_local
890 has performed all the frame alignment and size rounding for the
891 requested temporary. Note that extra space added for alignment
892 can be either above or below this stack slot depending on which
893 way the frame grows. We include the extra space if and only if it
894 is above this slot. */
895 if (FRAME_GROWS_DOWNWARD)
896 p->size = frame_offset_old - frame_offset;
897 else
898 p->size = size;
899
900 /* Now define the fields used by combine_temp_slots. */
901 if (FRAME_GROWS_DOWNWARD)
902 {
903 p->base_offset = frame_offset;
904 p->full_size = frame_offset_old - frame_offset;
905 }
906 else
907 {
908 p->base_offset = frame_offset_old;
909 p->full_size = frame_offset - frame_offset_old;
910 }
911
912 selected = p;
913 }
914
915 p = selected;
916 p->in_use = 1;
917 p->type = type;
918 p->level = temp_slot_level;
919 n_temp_slots_in_use++;
920
921 pp = temp_slots_at_level (p->level);
922 insert_slot_to_list (p, pp);
923 insert_temp_slot_address (XEXP (p->slot, 0), p);
924
925 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
926 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
927 vec_safe_push (stack_slot_list, slot);
928
929 /* If we know the alias set for the memory that will be used, use
930 it. If there's no TYPE, then we don't know anything about the
931 alias set for the memory. */
932 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
933 set_mem_align (slot, align);
934
935 /* If a type is specified, set the relevant flags. */
936 if (type != 0)
937 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
938 MEM_NOTRAP_P (slot) = 1;
939
940 return slot;
941 }
942
943 /* Allocate a temporary stack slot and record it for possible later
944 reuse. First two arguments are same as in preceding function. */
945
946 rtx
947 assign_stack_temp (machine_mode mode, poly_int64 size)
948 {
949 return assign_stack_temp_for_type (mode, size, NULL_TREE);
950 }
951 \f
952 /* Assign a temporary.
953 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
954 and so that should be used in error messages. In either case, we
955 allocate of the given type.
956 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
957 it is 0 if a register is OK.
958 DONT_PROMOTE is 1 if we should not promote values in register
959 to wider modes. */
960
961 rtx
962 assign_temp (tree type_or_decl, int memory_required,
963 int dont_promote ATTRIBUTE_UNUSED)
964 {
965 tree type, decl;
966 machine_mode mode;
967 #ifdef PROMOTE_MODE
968 int unsignedp;
969 #endif
970
971 if (DECL_P (type_or_decl))
972 decl = type_or_decl, type = TREE_TYPE (decl);
973 else
974 decl = NULL, type = type_or_decl;
975
976 mode = TYPE_MODE (type);
977 #ifdef PROMOTE_MODE
978 unsignedp = TYPE_UNSIGNED (type);
979 #endif
980
981 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
982 end. See also create_tmp_var for the gimplification-time check. */
983 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
984
985 if (mode == BLKmode || memory_required)
986 {
987 poly_int64 size;
988 rtx tmp;
989
990 /* Unfortunately, we don't yet know how to allocate variable-sized
991 temporaries. However, sometimes we can find a fixed upper limit on
992 the size, so try that instead. */
993 if (!poly_int_tree_p (TYPE_SIZE_UNIT (type), &size))
994 size = max_int_size_in_bytes (type);
995
996 /* Zero sized arrays are a GNU C extension. Set size to 1 to avoid
997 problems with allocating the stack space. */
998 if (known_eq (size, 0))
999 size = 1;
1000
1001 /* The size of the temporary may be too large to fit into an integer. */
1002 /* ??? Not sure this should happen except for user silliness, so limit
1003 this to things that aren't compiler-generated temporaries. The
1004 rest of the time we'll die in assign_stack_temp_for_type. */
1005 if (decl
1006 && !known_size_p (size)
1007 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1008 {
1009 error ("size of variable %q+D is too large", decl);
1010 size = 1;
1011 }
1012
1013 tmp = assign_stack_temp_for_type (mode, size, type);
1014 return tmp;
1015 }
1016
1017 #ifdef PROMOTE_MODE
1018 if (! dont_promote)
1019 mode = promote_mode (type, mode, &unsignedp);
1020 #endif
1021
1022 return gen_reg_rtx (mode);
1023 }
1024 \f
1025 /* Combine temporary stack slots which are adjacent on the stack.
1026
1027 This allows for better use of already allocated stack space. This is only
1028 done for BLKmode slots because we can be sure that we won't have alignment
1029 problems in this case. */
1030
1031 static void
1032 combine_temp_slots (void)
1033 {
1034 class temp_slot *p, *q, *next, *next_q;
1035 int num_slots;
1036
1037 /* We can't combine slots, because the information about which slot
1038 is in which alias set will be lost. */
1039 if (flag_strict_aliasing)
1040 return;
1041
1042 /* If there are a lot of temp slots, don't do anything unless
1043 high levels of optimization. */
1044 if (! flag_expensive_optimizations)
1045 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1046 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1047 return;
1048
1049 for (p = avail_temp_slots; p; p = next)
1050 {
1051 int delete_p = 0;
1052
1053 next = p->next;
1054
1055 if (GET_MODE (p->slot) != BLKmode)
1056 continue;
1057
1058 for (q = p->next; q; q = next_q)
1059 {
1060 int delete_q = 0;
1061
1062 next_q = q->next;
1063
1064 if (GET_MODE (q->slot) != BLKmode)
1065 continue;
1066
1067 if (known_eq (p->base_offset + p->full_size, q->base_offset))
1068 {
1069 /* Q comes after P; combine Q into P. */
1070 p->size += q->size;
1071 p->full_size += q->full_size;
1072 delete_q = 1;
1073 }
1074 else if (known_eq (q->base_offset + q->full_size, p->base_offset))
1075 {
1076 /* P comes after Q; combine P into Q. */
1077 q->size += p->size;
1078 q->full_size += p->full_size;
1079 delete_p = 1;
1080 break;
1081 }
1082 if (delete_q)
1083 cut_slot_from_list (q, &avail_temp_slots);
1084 }
1085
1086 /* Either delete P or advance past it. */
1087 if (delete_p)
1088 cut_slot_from_list (p, &avail_temp_slots);
1089 }
1090 }
1091 \f
1092 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1093 slot that previously was known by OLD_RTX. */
1094
1095 void
1096 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1097 {
1098 class temp_slot *p;
1099
1100 if (rtx_equal_p (old_rtx, new_rtx))
1101 return;
1102
1103 p = find_temp_slot_from_address (old_rtx);
1104
1105 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1106 NEW_RTX is a register, see if one operand of the PLUS is a
1107 temporary location. If so, NEW_RTX points into it. Otherwise,
1108 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1109 in common between them. If so, try a recursive call on those
1110 values. */
1111 if (p == 0)
1112 {
1113 if (GET_CODE (old_rtx) != PLUS)
1114 return;
1115
1116 if (REG_P (new_rtx))
1117 {
1118 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1119 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1120 return;
1121 }
1122 else if (GET_CODE (new_rtx) != PLUS)
1123 return;
1124
1125 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1126 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1127 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1128 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1129 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1130 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1131 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1132 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1133
1134 return;
1135 }
1136
1137 /* Otherwise add an alias for the temp's address. */
1138 insert_temp_slot_address (new_rtx, p);
1139 }
1140
1141 /* If X could be a reference to a temporary slot, mark that slot as
1142 belonging to the to one level higher than the current level. If X
1143 matched one of our slots, just mark that one. Otherwise, we can't
1144 easily predict which it is, so upgrade all of them.
1145
1146 This is called when an ({...}) construct occurs and a statement
1147 returns a value in memory. */
1148
1149 void
1150 preserve_temp_slots (rtx x)
1151 {
1152 class temp_slot *p = 0, *next;
1153
1154 if (x == 0)
1155 return;
1156
1157 /* If X is a register that is being used as a pointer, see if we have
1158 a temporary slot we know it points to. */
1159 if (REG_P (x) && REG_POINTER (x))
1160 p = find_temp_slot_from_address (x);
1161
1162 /* If X is not in memory or is at a constant address, it cannot be in
1163 a temporary slot. */
1164 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1165 return;
1166
1167 /* First see if we can find a match. */
1168 if (p == 0)
1169 p = find_temp_slot_from_address (XEXP (x, 0));
1170
1171 if (p != 0)
1172 {
1173 if (p->level == temp_slot_level)
1174 move_slot_to_level (p, temp_slot_level - 1);
1175 return;
1176 }
1177
1178 /* Otherwise, preserve all non-kept slots at this level. */
1179 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1180 {
1181 next = p->next;
1182 move_slot_to_level (p, temp_slot_level - 1);
1183 }
1184 }
1185
1186 /* Free all temporaries used so far. This is normally called at the
1187 end of generating code for a statement. */
1188
1189 void
1190 free_temp_slots (void)
1191 {
1192 class temp_slot *p, *next;
1193 bool some_available = false;
1194
1195 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1196 {
1197 next = p->next;
1198 make_slot_available (p);
1199 some_available = true;
1200 }
1201
1202 if (some_available)
1203 {
1204 remove_unused_temp_slot_addresses ();
1205 combine_temp_slots ();
1206 }
1207 }
1208
1209 /* Push deeper into the nesting level for stack temporaries. */
1210
1211 void
1212 push_temp_slots (void)
1213 {
1214 temp_slot_level++;
1215 }
1216
1217 /* Pop a temporary nesting level. All slots in use in the current level
1218 are freed. */
1219
1220 void
1221 pop_temp_slots (void)
1222 {
1223 free_temp_slots ();
1224 temp_slot_level--;
1225 }
1226
1227 /* Initialize temporary slots. */
1228
1229 void
1230 init_temp_slots (void)
1231 {
1232 /* We have not allocated any temporaries yet. */
1233 avail_temp_slots = 0;
1234 vec_alloc (used_temp_slots, 0);
1235 temp_slot_level = 0;
1236 n_temp_slots_in_use = 0;
1237
1238 /* Set up the table to map addresses to temp slots. */
1239 if (! temp_slot_address_table)
1240 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1241 else
1242 temp_slot_address_table->empty ();
1243 }
1244 \f
1245 /* Functions and data structures to keep track of the values hard regs
1246 had at the start of the function. */
1247
1248 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1249 and has_hard_reg_initial_val.. */
1250 struct GTY(()) initial_value_pair {
1251 rtx hard_reg;
1252 rtx pseudo;
1253 };
1254 /* ??? This could be a VEC but there is currently no way to define an
1255 opaque VEC type. This could be worked around by defining struct
1256 initial_value_pair in function.h. */
1257 struct GTY(()) initial_value_struct {
1258 int num_entries;
1259 int max_entries;
1260 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1261 };
1262
1263 /* If a pseudo represents an initial hard reg (or expression), return
1264 it, else return NULL_RTX. */
1265
1266 rtx
1267 get_hard_reg_initial_reg (rtx reg)
1268 {
1269 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1270 int i;
1271
1272 if (ivs == 0)
1273 return NULL_RTX;
1274
1275 for (i = 0; i < ivs->num_entries; i++)
1276 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1277 return ivs->entries[i].hard_reg;
1278
1279 return NULL_RTX;
1280 }
1281
1282 /* Make sure that there's a pseudo register of mode MODE that stores the
1283 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1284
1285 rtx
1286 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1287 {
1288 struct initial_value_struct *ivs;
1289 rtx rv;
1290
1291 rv = has_hard_reg_initial_val (mode, regno);
1292 if (rv)
1293 return rv;
1294
1295 ivs = crtl->hard_reg_initial_vals;
1296 if (ivs == 0)
1297 {
1298 ivs = ggc_alloc<initial_value_struct> ();
1299 ivs->num_entries = 0;
1300 ivs->max_entries = 5;
1301 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1302 crtl->hard_reg_initial_vals = ivs;
1303 }
1304
1305 if (ivs->num_entries >= ivs->max_entries)
1306 {
1307 ivs->max_entries += 5;
1308 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1309 ivs->max_entries);
1310 }
1311
1312 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1313 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1314
1315 return ivs->entries[ivs->num_entries++].pseudo;
1316 }
1317
1318 /* See if get_hard_reg_initial_val has been used to create a pseudo
1319 for the initial value of hard register REGNO in mode MODE. Return
1320 the associated pseudo if so, otherwise return NULL. */
1321
1322 rtx
1323 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1324 {
1325 struct initial_value_struct *ivs;
1326 int i;
1327
1328 ivs = crtl->hard_reg_initial_vals;
1329 if (ivs != 0)
1330 for (i = 0; i < ivs->num_entries; i++)
1331 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1332 && REGNO (ivs->entries[i].hard_reg) == regno)
1333 return ivs->entries[i].pseudo;
1334
1335 return NULL_RTX;
1336 }
1337
1338 unsigned int
1339 emit_initial_value_sets (void)
1340 {
1341 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1342 int i;
1343 rtx_insn *seq;
1344
1345 if (ivs == 0)
1346 return 0;
1347
1348 start_sequence ();
1349 for (i = 0; i < ivs->num_entries; i++)
1350 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1351 seq = get_insns ();
1352 end_sequence ();
1353
1354 emit_insn_at_entry (seq);
1355 return 0;
1356 }
1357
1358 /* Return the hardreg-pseudoreg initial values pair entry I and
1359 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1360 bool
1361 initial_value_entry (int i, rtx *hreg, rtx *preg)
1362 {
1363 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1364 if (!ivs || i >= ivs->num_entries)
1365 return false;
1366
1367 *hreg = ivs->entries[i].hard_reg;
1368 *preg = ivs->entries[i].pseudo;
1369 return true;
1370 }
1371 \f
1372 /* These routines are responsible for converting virtual register references
1373 to the actual hard register references once RTL generation is complete.
1374
1375 The following four variables are used for communication between the
1376 routines. They contain the offsets of the virtual registers from their
1377 respective hard registers. */
1378
1379 static poly_int64 in_arg_offset;
1380 static poly_int64 var_offset;
1381 static poly_int64 dynamic_offset;
1382 static poly_int64 out_arg_offset;
1383 static poly_int64 cfa_offset;
1384
1385 /* In most machines, the stack pointer register is equivalent to the bottom
1386 of the stack. */
1387
1388 #ifndef STACK_POINTER_OFFSET
1389 #define STACK_POINTER_OFFSET 0
1390 #endif
1391
1392 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1393 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1394 #endif
1395
1396 /* If not defined, pick an appropriate default for the offset of dynamically
1397 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1398 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1399
1400 #ifndef STACK_DYNAMIC_OFFSET
1401
1402 /* The bottom of the stack points to the actual arguments. If
1403 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1404 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1405 stack space for register parameters is not pushed by the caller, but
1406 rather part of the fixed stack areas and hence not included in
1407 `crtl->outgoing_args_size'. Nevertheless, we must allow
1408 for it when allocating stack dynamic objects. */
1409
1410 #ifdef INCOMING_REG_PARM_STACK_SPACE
1411 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1412 ((ACCUMULATE_OUTGOING_ARGS \
1413 ? (crtl->outgoing_args_size \
1414 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1415 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1416 : 0) + (STACK_POINTER_OFFSET))
1417 #else
1418 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1419 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : poly_int64 (0)) \
1420 + (STACK_POINTER_OFFSET))
1421 #endif
1422 #endif
1423
1424 \f
1425 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1426 is a virtual register, return the equivalent hard register and set the
1427 offset indirectly through the pointer. Otherwise, return 0. */
1428
1429 static rtx
1430 instantiate_new_reg (rtx x, poly_int64_pod *poffset)
1431 {
1432 rtx new_rtx;
1433 poly_int64 offset;
1434
1435 if (x == virtual_incoming_args_rtx)
1436 {
1437 if (stack_realign_drap)
1438 {
1439 /* Replace virtual_incoming_args_rtx with internal arg
1440 pointer if DRAP is used to realign stack. */
1441 new_rtx = crtl->args.internal_arg_pointer;
1442 offset = 0;
1443 }
1444 else
1445 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1446 }
1447 else if (x == virtual_stack_vars_rtx)
1448 new_rtx = frame_pointer_rtx, offset = var_offset;
1449 else if (x == virtual_stack_dynamic_rtx)
1450 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1451 else if (x == virtual_outgoing_args_rtx)
1452 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1453 else if (x == virtual_cfa_rtx)
1454 {
1455 #ifdef FRAME_POINTER_CFA_OFFSET
1456 new_rtx = frame_pointer_rtx;
1457 #else
1458 new_rtx = arg_pointer_rtx;
1459 #endif
1460 offset = cfa_offset;
1461 }
1462 else if (x == virtual_preferred_stack_boundary_rtx)
1463 {
1464 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1465 offset = 0;
1466 }
1467 else
1468 return NULL_RTX;
1469
1470 *poffset = offset;
1471 return new_rtx;
1472 }
1473
1474 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1475 registers present inside of *LOC. The expression is simplified,
1476 as much as possible, but is not to be considered "valid" in any sense
1477 implied by the target. Return true if any change is made. */
1478
1479 static bool
1480 instantiate_virtual_regs_in_rtx (rtx *loc)
1481 {
1482 if (!*loc)
1483 return false;
1484 bool changed = false;
1485 subrtx_ptr_iterator::array_type array;
1486 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1487 {
1488 rtx *loc = *iter;
1489 if (rtx x = *loc)
1490 {
1491 rtx new_rtx;
1492 poly_int64 offset;
1493 switch (GET_CODE (x))
1494 {
1495 case REG:
1496 new_rtx = instantiate_new_reg (x, &offset);
1497 if (new_rtx)
1498 {
1499 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1500 changed = true;
1501 }
1502 iter.skip_subrtxes ();
1503 break;
1504
1505 case PLUS:
1506 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1507 if (new_rtx)
1508 {
1509 XEXP (x, 0) = new_rtx;
1510 *loc = plus_constant (GET_MODE (x), x, offset, true);
1511 changed = true;
1512 iter.skip_subrtxes ();
1513 break;
1514 }
1515
1516 /* FIXME -- from old code */
1517 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1518 we can commute the PLUS and SUBREG because pointers into the
1519 frame are well-behaved. */
1520 break;
1521
1522 default:
1523 break;
1524 }
1525 }
1526 }
1527 return changed;
1528 }
1529
1530 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1531 matches the predicate for insn CODE operand OPERAND. */
1532
1533 static int
1534 safe_insn_predicate (int code, int operand, rtx x)
1535 {
1536 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1537 }
1538
1539 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1540 registers present inside of insn. The result will be a valid insn. */
1541
1542 static void
1543 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1544 {
1545 poly_int64 offset;
1546 int insn_code, i;
1547 bool any_change = false;
1548 rtx set, new_rtx, x;
1549 rtx_insn *seq;
1550
1551 /* There are some special cases to be handled first. */
1552 set = single_set (insn);
1553 if (set)
1554 {
1555 /* We're allowed to assign to a virtual register. This is interpreted
1556 to mean that the underlying register gets assigned the inverse
1557 transformation. This is used, for example, in the handling of
1558 non-local gotos. */
1559 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1560 if (new_rtx)
1561 {
1562 start_sequence ();
1563
1564 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1565 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1566 gen_int_mode (-offset, GET_MODE (new_rtx)));
1567 x = force_operand (x, new_rtx);
1568 if (x != new_rtx)
1569 emit_move_insn (new_rtx, x);
1570
1571 seq = get_insns ();
1572 end_sequence ();
1573
1574 emit_insn_before (seq, insn);
1575 delete_insn (insn);
1576 return;
1577 }
1578
1579 /* Handle a straight copy from a virtual register by generating a
1580 new add insn. The difference between this and falling through
1581 to the generic case is avoiding a new pseudo and eliminating a
1582 move insn in the initial rtl stream. */
1583 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1584 if (new_rtx
1585 && maybe_ne (offset, 0)
1586 && REG_P (SET_DEST (set))
1587 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1588 {
1589 start_sequence ();
1590
1591 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1592 gen_int_mode (offset,
1593 GET_MODE (SET_DEST (set))),
1594 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1595 if (x != SET_DEST (set))
1596 emit_move_insn (SET_DEST (set), x);
1597
1598 seq = get_insns ();
1599 end_sequence ();
1600
1601 emit_insn_before (seq, insn);
1602 delete_insn (insn);
1603 return;
1604 }
1605
1606 extract_insn (insn);
1607 insn_code = INSN_CODE (insn);
1608
1609 /* Handle a plus involving a virtual register by determining if the
1610 operands remain valid if they're modified in place. */
1611 poly_int64 delta;
1612 if (GET_CODE (SET_SRC (set)) == PLUS
1613 && recog_data.n_operands >= 3
1614 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1615 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1616 && poly_int_rtx_p (recog_data.operand[2], &delta)
1617 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1618 {
1619 offset += delta;
1620
1621 /* If the sum is zero, then replace with a plain move. */
1622 if (known_eq (offset, 0)
1623 && REG_P (SET_DEST (set))
1624 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1625 {
1626 start_sequence ();
1627 emit_move_insn (SET_DEST (set), new_rtx);
1628 seq = get_insns ();
1629 end_sequence ();
1630
1631 emit_insn_before (seq, insn);
1632 delete_insn (insn);
1633 return;
1634 }
1635
1636 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1637
1638 /* Using validate_change and apply_change_group here leaves
1639 recog_data in an invalid state. Since we know exactly what
1640 we want to check, do those two by hand. */
1641 if (safe_insn_predicate (insn_code, 1, new_rtx)
1642 && safe_insn_predicate (insn_code, 2, x))
1643 {
1644 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1645 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1646 any_change = true;
1647
1648 /* Fall through into the regular operand fixup loop in
1649 order to take care of operands other than 1 and 2. */
1650 }
1651 }
1652 }
1653 else
1654 {
1655 extract_insn (insn);
1656 insn_code = INSN_CODE (insn);
1657 }
1658
1659 /* In the general case, we expect virtual registers to appear only in
1660 operands, and then only as either bare registers or inside memories. */
1661 for (i = 0; i < recog_data.n_operands; ++i)
1662 {
1663 x = recog_data.operand[i];
1664 switch (GET_CODE (x))
1665 {
1666 case MEM:
1667 {
1668 rtx addr = XEXP (x, 0);
1669
1670 if (!instantiate_virtual_regs_in_rtx (&addr))
1671 continue;
1672
1673 start_sequence ();
1674 x = replace_equiv_address (x, addr, true);
1675 /* It may happen that the address with the virtual reg
1676 was valid (e.g. based on the virtual stack reg, which might
1677 be acceptable to the predicates with all offsets), whereas
1678 the address now isn't anymore, for instance when the address
1679 is still offsetted, but the base reg isn't virtual-stack-reg
1680 anymore. Below we would do a force_reg on the whole operand,
1681 but this insn might actually only accept memory. Hence,
1682 before doing that last resort, try to reload the address into
1683 a register, so this operand stays a MEM. */
1684 if (!safe_insn_predicate (insn_code, i, x))
1685 {
1686 addr = force_reg (GET_MODE (addr), addr);
1687 x = replace_equiv_address (x, addr, true);
1688 }
1689 seq = get_insns ();
1690 end_sequence ();
1691 if (seq)
1692 emit_insn_before (seq, insn);
1693 }
1694 break;
1695
1696 case REG:
1697 new_rtx = instantiate_new_reg (x, &offset);
1698 if (new_rtx == NULL)
1699 continue;
1700 if (known_eq (offset, 0))
1701 x = new_rtx;
1702 else
1703 {
1704 start_sequence ();
1705
1706 /* Careful, special mode predicates may have stuff in
1707 insn_data[insn_code].operand[i].mode that isn't useful
1708 to us for computing a new value. */
1709 /* ??? Recognize address_operand and/or "p" constraints
1710 to see if (plus new offset) is a valid before we put
1711 this through expand_simple_binop. */
1712 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1713 gen_int_mode (offset, GET_MODE (x)),
1714 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1715 seq = get_insns ();
1716 end_sequence ();
1717 emit_insn_before (seq, insn);
1718 }
1719 break;
1720
1721 case SUBREG:
1722 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1723 if (new_rtx == NULL)
1724 continue;
1725 if (maybe_ne (offset, 0))
1726 {
1727 start_sequence ();
1728 new_rtx = expand_simple_binop
1729 (GET_MODE (new_rtx), PLUS, new_rtx,
1730 gen_int_mode (offset, GET_MODE (new_rtx)),
1731 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1732 seq = get_insns ();
1733 end_sequence ();
1734 emit_insn_before (seq, insn);
1735 }
1736 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1737 GET_MODE (new_rtx), SUBREG_BYTE (x));
1738 gcc_assert (x);
1739 break;
1740
1741 default:
1742 continue;
1743 }
1744
1745 /* At this point, X contains the new value for the operand.
1746 Validate the new value vs the insn predicate. Note that
1747 asm insns will have insn_code -1 here. */
1748 if (!safe_insn_predicate (insn_code, i, x))
1749 {
1750 start_sequence ();
1751 if (REG_P (x))
1752 {
1753 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1754 x = copy_to_reg (x);
1755 }
1756 else
1757 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1758 seq = get_insns ();
1759 end_sequence ();
1760 if (seq)
1761 emit_insn_before (seq, insn);
1762 }
1763
1764 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1765 any_change = true;
1766 }
1767
1768 if (any_change)
1769 {
1770 /* Propagate operand changes into the duplicates. */
1771 for (i = 0; i < recog_data.n_dups; ++i)
1772 *recog_data.dup_loc[i]
1773 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1774
1775 /* Force re-recognition of the instruction for validation. */
1776 INSN_CODE (insn) = -1;
1777 }
1778
1779 if (asm_noperands (PATTERN (insn)) >= 0)
1780 {
1781 if (!check_asm_operands (PATTERN (insn)))
1782 {
1783 error_for_asm (insn, "impossible constraint in %<asm%>");
1784 /* For asm goto, instead of fixing up all the edges
1785 just clear the template and clear input operands
1786 (asm goto doesn't have any output operands). */
1787 if (JUMP_P (insn))
1788 {
1789 rtx asm_op = extract_asm_operands (PATTERN (insn));
1790 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1791 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1792 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1793 }
1794 else
1795 delete_insn (insn);
1796 }
1797 }
1798 else
1799 {
1800 if (recog_memoized (insn) < 0)
1801 fatal_insn_not_found (insn);
1802 }
1803 }
1804
1805 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1806 do any instantiation required. */
1807
1808 void
1809 instantiate_decl_rtl (rtx x)
1810 {
1811 rtx addr;
1812
1813 if (x == 0)
1814 return;
1815
1816 /* If this is a CONCAT, recurse for the pieces. */
1817 if (GET_CODE (x) == CONCAT)
1818 {
1819 instantiate_decl_rtl (XEXP (x, 0));
1820 instantiate_decl_rtl (XEXP (x, 1));
1821 return;
1822 }
1823
1824 /* If this is not a MEM, no need to do anything. Similarly if the
1825 address is a constant or a register that is not a virtual register. */
1826 if (!MEM_P (x))
1827 return;
1828
1829 addr = XEXP (x, 0);
1830 if (CONSTANT_P (addr)
1831 || (REG_P (addr)
1832 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1833 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1834 return;
1835
1836 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1837 }
1838
1839 /* Helper for instantiate_decls called via walk_tree: Process all decls
1840 in the given DECL_VALUE_EXPR. */
1841
1842 static tree
1843 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1844 {
1845 tree t = *tp;
1846 if (! EXPR_P (t))
1847 {
1848 *walk_subtrees = 0;
1849 if (DECL_P (t))
1850 {
1851 if (DECL_RTL_SET_P (t))
1852 instantiate_decl_rtl (DECL_RTL (t));
1853 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1854 && DECL_INCOMING_RTL (t))
1855 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1856 if ((VAR_P (t) || TREE_CODE (t) == RESULT_DECL)
1857 && DECL_HAS_VALUE_EXPR_P (t))
1858 {
1859 tree v = DECL_VALUE_EXPR (t);
1860 walk_tree (&v, instantiate_expr, NULL, NULL);
1861 }
1862 }
1863 }
1864 return NULL;
1865 }
1866
1867 /* Subroutine of instantiate_decls: Process all decls in the given
1868 BLOCK node and all its subblocks. */
1869
1870 static void
1871 instantiate_decls_1 (tree let)
1872 {
1873 tree t;
1874
1875 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1876 {
1877 if (DECL_RTL_SET_P (t))
1878 instantiate_decl_rtl (DECL_RTL (t));
1879 if (VAR_P (t) && DECL_HAS_VALUE_EXPR_P (t))
1880 {
1881 tree v = DECL_VALUE_EXPR (t);
1882 walk_tree (&v, instantiate_expr, NULL, NULL);
1883 }
1884 }
1885
1886 /* Process all subblocks. */
1887 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1888 instantiate_decls_1 (t);
1889 }
1890
1891 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1892 all virtual registers in their DECL_RTL's. */
1893
1894 static void
1895 instantiate_decls (tree fndecl)
1896 {
1897 tree decl;
1898 unsigned ix;
1899
1900 /* Process all parameters of the function. */
1901 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1902 {
1903 instantiate_decl_rtl (DECL_RTL (decl));
1904 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1905 if (DECL_HAS_VALUE_EXPR_P (decl))
1906 {
1907 tree v = DECL_VALUE_EXPR (decl);
1908 walk_tree (&v, instantiate_expr, NULL, NULL);
1909 }
1910 }
1911
1912 if ((decl = DECL_RESULT (fndecl))
1913 && TREE_CODE (decl) == RESULT_DECL)
1914 {
1915 if (DECL_RTL_SET_P (decl))
1916 instantiate_decl_rtl (DECL_RTL (decl));
1917 if (DECL_HAS_VALUE_EXPR_P (decl))
1918 {
1919 tree v = DECL_VALUE_EXPR (decl);
1920 walk_tree (&v, instantiate_expr, NULL, NULL);
1921 }
1922 }
1923
1924 /* Process the saved static chain if it exists. */
1925 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1926 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1927 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1928
1929 /* Now process all variables defined in the function or its subblocks. */
1930 if (DECL_INITIAL (fndecl))
1931 instantiate_decls_1 (DECL_INITIAL (fndecl));
1932
1933 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1934 if (DECL_RTL_SET_P (decl))
1935 instantiate_decl_rtl (DECL_RTL (decl));
1936 vec_free (cfun->local_decls);
1937 }
1938
1939 /* Pass through the INSNS of function FNDECL and convert virtual register
1940 references to hard register references. */
1941
1942 static unsigned int
1943 instantiate_virtual_regs (void)
1944 {
1945 rtx_insn *insn;
1946
1947 /* Compute the offsets to use for this function. */
1948 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1949 var_offset = targetm.starting_frame_offset ();
1950 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1951 out_arg_offset = STACK_POINTER_OFFSET;
1952 #ifdef FRAME_POINTER_CFA_OFFSET
1953 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1954 #else
1955 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1956 #endif
1957
1958 /* Initialize recognition, indicating that volatile is OK. */
1959 init_recog ();
1960
1961 /* Scan through all the insns, instantiating every virtual register still
1962 present. */
1963 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1964 if (INSN_P (insn))
1965 {
1966 /* These patterns in the instruction stream can never be recognized.
1967 Fortunately, they shouldn't contain virtual registers either. */
1968 if (GET_CODE (PATTERN (insn)) == USE
1969 || GET_CODE (PATTERN (insn)) == CLOBBER
1970 || GET_CODE (PATTERN (insn)) == ASM_INPUT
1971 || DEBUG_MARKER_INSN_P (insn))
1972 continue;
1973 else if (DEBUG_BIND_INSN_P (insn))
1974 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn));
1975 else
1976 instantiate_virtual_regs_in_insn (insn);
1977
1978 if (insn->deleted ())
1979 continue;
1980
1981 instantiate_virtual_regs_in_rtx (&REG_NOTES (insn));
1982
1983 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1984 if (CALL_P (insn))
1985 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1986 }
1987
1988 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1989 instantiate_decls (current_function_decl);
1990
1991 targetm.instantiate_decls ();
1992
1993 /* Indicate that, from now on, assign_stack_local should use
1994 frame_pointer_rtx. */
1995 virtuals_instantiated = 1;
1996
1997 return 0;
1998 }
1999
2000 namespace {
2001
2002 const pass_data pass_data_instantiate_virtual_regs =
2003 {
2004 RTL_PASS, /* type */
2005 "vregs", /* name */
2006 OPTGROUP_NONE, /* optinfo_flags */
2007 TV_NONE, /* tv_id */
2008 0, /* properties_required */
2009 0, /* properties_provided */
2010 0, /* properties_destroyed */
2011 0, /* todo_flags_start */
2012 0, /* todo_flags_finish */
2013 };
2014
2015 class pass_instantiate_virtual_regs : public rtl_opt_pass
2016 {
2017 public:
2018 pass_instantiate_virtual_regs (gcc::context *ctxt)
2019 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2020 {}
2021
2022 /* opt_pass methods: */
2023 virtual unsigned int execute (function *)
2024 {
2025 return instantiate_virtual_regs ();
2026 }
2027
2028 }; // class pass_instantiate_virtual_regs
2029
2030 } // anon namespace
2031
2032 rtl_opt_pass *
2033 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2034 {
2035 return new pass_instantiate_virtual_regs (ctxt);
2036 }
2037
2038 \f
2039 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2040 This means a type for which function calls must pass an address to the
2041 function or get an address back from the function.
2042 EXP may be a type node or an expression (whose type is tested). */
2043
2044 int
2045 aggregate_value_p (const_tree exp, const_tree fntype)
2046 {
2047 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2048 int i, regno, nregs;
2049 rtx reg;
2050
2051 if (fntype)
2052 switch (TREE_CODE (fntype))
2053 {
2054 case CALL_EXPR:
2055 {
2056 tree fndecl = get_callee_fndecl (fntype);
2057 if (fndecl)
2058 fntype = TREE_TYPE (fndecl);
2059 else if (CALL_EXPR_FN (fntype))
2060 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2061 else
2062 /* For internal functions, assume nothing needs to be
2063 returned in memory. */
2064 return 0;
2065 }
2066 break;
2067 case FUNCTION_DECL:
2068 fntype = TREE_TYPE (fntype);
2069 break;
2070 case FUNCTION_TYPE:
2071 case METHOD_TYPE:
2072 break;
2073 case IDENTIFIER_NODE:
2074 fntype = NULL_TREE;
2075 break;
2076 default:
2077 /* We don't expect other tree types here. */
2078 gcc_unreachable ();
2079 }
2080
2081 if (VOID_TYPE_P (type))
2082 return 0;
2083
2084 /* If a record should be passed the same as its first (and only) member
2085 don't pass it as an aggregate. */
2086 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2087 return aggregate_value_p (first_field (type), fntype);
2088
2089 /* If the front end has decided that this needs to be passed by
2090 reference, do so. */
2091 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2092 && DECL_BY_REFERENCE (exp))
2093 return 1;
2094
2095 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2096 if (fntype && TREE_ADDRESSABLE (fntype))
2097 return 1;
2098
2099 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2100 and thus can't be returned in registers. */
2101 if (TREE_ADDRESSABLE (type))
2102 return 1;
2103
2104 if (TYPE_EMPTY_P (type))
2105 return 0;
2106
2107 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2108 return 1;
2109
2110 if (targetm.calls.return_in_memory (type, fntype))
2111 return 1;
2112
2113 /* Make sure we have suitable call-clobbered regs to return
2114 the value in; if not, we must return it in memory. */
2115 reg = hard_function_value (type, 0, fntype, 0);
2116
2117 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2118 it is OK. */
2119 if (!REG_P (reg))
2120 return 0;
2121
2122 regno = REGNO (reg);
2123 nregs = hard_regno_nregs (regno, TYPE_MODE (type));
2124 for (i = 0; i < nregs; i++)
2125 if (! call_used_regs[regno + i])
2126 return 1;
2127
2128 return 0;
2129 }
2130 \f
2131 /* Return true if we should assign DECL a pseudo register; false if it
2132 should live on the local stack. */
2133
2134 bool
2135 use_register_for_decl (const_tree decl)
2136 {
2137 if (TREE_CODE (decl) == SSA_NAME)
2138 {
2139 /* We often try to use the SSA_NAME, instead of its underlying
2140 decl, to get type information and guide decisions, to avoid
2141 differences of behavior between anonymous and named
2142 variables, but in this one case we have to go for the actual
2143 variable if there is one. The main reason is that, at least
2144 at -O0, we want to place user variables on the stack, but we
2145 don't mind using pseudos for anonymous or ignored temps.
2146 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2147 should go in pseudos, whereas their corresponding variables
2148 might have to go on the stack. So, disregarding the decl
2149 here would negatively impact debug info at -O0, enable
2150 coalescing between SSA_NAMEs that ought to get different
2151 stack/pseudo assignments, and get the incoming argument
2152 processing thoroughly confused by PARM_DECLs expected to live
2153 in stack slots but assigned to pseudos. */
2154 if (!SSA_NAME_VAR (decl))
2155 return TYPE_MODE (TREE_TYPE (decl)) != BLKmode
2156 && !(flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)));
2157
2158 decl = SSA_NAME_VAR (decl);
2159 }
2160
2161 /* Honor volatile. */
2162 if (TREE_SIDE_EFFECTS (decl))
2163 return false;
2164
2165 /* Honor addressability. */
2166 if (TREE_ADDRESSABLE (decl))
2167 return false;
2168
2169 /* RESULT_DECLs are a bit special in that they're assigned without
2170 regard to use_register_for_decl, but we generally only store in
2171 them. If we coalesce their SSA NAMEs, we'd better return a
2172 result that matches the assignment in expand_function_start. */
2173 if (TREE_CODE (decl) == RESULT_DECL)
2174 {
2175 /* If it's not an aggregate, we're going to use a REG or a
2176 PARALLEL containing a REG. */
2177 if (!aggregate_value_p (decl, current_function_decl))
2178 return true;
2179
2180 /* If expand_function_start determines the return value, we'll
2181 use MEM if it's not by reference. */
2182 if (cfun->returns_pcc_struct
2183 || (targetm.calls.struct_value_rtx
2184 (TREE_TYPE (current_function_decl), 1)))
2185 return DECL_BY_REFERENCE (decl);
2186
2187 /* Otherwise, we're taking an extra all.function_result_decl
2188 argument. It's set up in assign_parms_augmented_arg_list,
2189 under the (negated) conditions above, and then it's used to
2190 set up the RESULT_DECL rtl in assign_params, after looping
2191 over all parameters. Now, if the RESULT_DECL is not by
2192 reference, we'll use a MEM either way. */
2193 if (!DECL_BY_REFERENCE (decl))
2194 return false;
2195
2196 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2197 the function_result_decl's assignment. Since it's a pointer,
2198 we can short-circuit a number of the tests below, and we must
2199 duplicat e them because we don't have the
2200 function_result_decl to test. */
2201 if (!targetm.calls.allocate_stack_slots_for_args ())
2202 return true;
2203 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2204 if (optimize)
2205 return true;
2206 /* We don't set DECL_REGISTER for the function_result_decl. */
2207 return false;
2208 }
2209
2210 /* Only register-like things go in registers. */
2211 if (DECL_MODE (decl) == BLKmode)
2212 return false;
2213
2214 /* If -ffloat-store specified, don't put explicit float variables
2215 into registers. */
2216 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2217 propagates values across these stores, and it probably shouldn't. */
2218 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2219 return false;
2220
2221 if (!targetm.calls.allocate_stack_slots_for_args ())
2222 return true;
2223
2224 /* If we're not interested in tracking debugging information for
2225 this decl, then we can certainly put it in a register. */
2226 if (DECL_IGNORED_P (decl))
2227 return true;
2228
2229 if (optimize)
2230 return true;
2231
2232 if (!DECL_REGISTER (decl))
2233 return false;
2234
2235 /* When not optimizing, disregard register keyword for types that
2236 could have methods, otherwise the methods won't be callable from
2237 the debugger. */
2238 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl)))
2239 return false;
2240
2241 return true;
2242 }
2243
2244 /* Structures to communicate between the subroutines of assign_parms.
2245 The first holds data persistent across all parameters, the second
2246 is cleared out for each parameter. */
2247
2248 struct assign_parm_data_all
2249 {
2250 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2251 should become a job of the target or otherwise encapsulated. */
2252 CUMULATIVE_ARGS args_so_far_v;
2253 cumulative_args_t args_so_far;
2254 struct args_size stack_args_size;
2255 tree function_result_decl;
2256 tree orig_fnargs;
2257 rtx_insn *first_conversion_insn;
2258 rtx_insn *last_conversion_insn;
2259 HOST_WIDE_INT pretend_args_size;
2260 HOST_WIDE_INT extra_pretend_bytes;
2261 int reg_parm_stack_space;
2262 };
2263
2264 struct assign_parm_data_one
2265 {
2266 tree nominal_type;
2267 tree passed_type;
2268 rtx entry_parm;
2269 rtx stack_parm;
2270 machine_mode nominal_mode;
2271 machine_mode passed_mode;
2272 machine_mode promoted_mode;
2273 struct locate_and_pad_arg_data locate;
2274 int partial;
2275 BOOL_BITFIELD named_arg : 1;
2276 BOOL_BITFIELD passed_pointer : 1;
2277 };
2278
2279 /* A subroutine of assign_parms. Initialize ALL. */
2280
2281 static void
2282 assign_parms_initialize_all (struct assign_parm_data_all *all)
2283 {
2284 tree fntype ATTRIBUTE_UNUSED;
2285
2286 memset (all, 0, sizeof (*all));
2287
2288 fntype = TREE_TYPE (current_function_decl);
2289
2290 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2291 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2292 #else
2293 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2294 current_function_decl, -1);
2295 #endif
2296 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2297
2298 #ifdef INCOMING_REG_PARM_STACK_SPACE
2299 all->reg_parm_stack_space
2300 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2301 #endif
2302 }
2303
2304 /* If ARGS contains entries with complex types, split the entry into two
2305 entries of the component type. Return a new list of substitutions are
2306 needed, else the old list. */
2307
2308 static void
2309 split_complex_args (vec<tree> *args)
2310 {
2311 unsigned i;
2312 tree p;
2313
2314 FOR_EACH_VEC_ELT (*args, i, p)
2315 {
2316 tree type = TREE_TYPE (p);
2317 if (TREE_CODE (type) == COMPLEX_TYPE
2318 && targetm.calls.split_complex_arg (type))
2319 {
2320 tree decl;
2321 tree subtype = TREE_TYPE (type);
2322 bool addressable = TREE_ADDRESSABLE (p);
2323
2324 /* Rewrite the PARM_DECL's type with its component. */
2325 p = copy_node (p);
2326 TREE_TYPE (p) = subtype;
2327 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2328 SET_DECL_MODE (p, VOIDmode);
2329 DECL_SIZE (p) = NULL;
2330 DECL_SIZE_UNIT (p) = NULL;
2331 /* If this arg must go in memory, put it in a pseudo here.
2332 We can't allow it to go in memory as per normal parms,
2333 because the usual place might not have the imag part
2334 adjacent to the real part. */
2335 DECL_ARTIFICIAL (p) = addressable;
2336 DECL_IGNORED_P (p) = addressable;
2337 TREE_ADDRESSABLE (p) = 0;
2338 layout_decl (p, 0);
2339 (*args)[i] = p;
2340
2341 /* Build a second synthetic decl. */
2342 decl = build_decl (EXPR_LOCATION (p),
2343 PARM_DECL, NULL_TREE, subtype);
2344 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2345 DECL_ARTIFICIAL (decl) = addressable;
2346 DECL_IGNORED_P (decl) = addressable;
2347 layout_decl (decl, 0);
2348 args->safe_insert (++i, decl);
2349 }
2350 }
2351 }
2352
2353 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2354 the hidden struct return argument, and (abi willing) complex args.
2355 Return the new parameter list. */
2356
2357 static vec<tree>
2358 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2359 {
2360 tree fndecl = current_function_decl;
2361 tree fntype = TREE_TYPE (fndecl);
2362 vec<tree> fnargs = vNULL;
2363 tree arg;
2364
2365 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2366 fnargs.safe_push (arg);
2367
2368 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2369
2370 /* If struct value address is treated as the first argument, make it so. */
2371 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2372 && ! cfun->returns_pcc_struct
2373 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2374 {
2375 tree type = build_pointer_type (TREE_TYPE (fntype));
2376 tree decl;
2377
2378 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2379 PARM_DECL, get_identifier (".result_ptr"), type);
2380 DECL_ARG_TYPE (decl) = type;
2381 DECL_ARTIFICIAL (decl) = 1;
2382 DECL_NAMELESS (decl) = 1;
2383 TREE_CONSTANT (decl) = 1;
2384 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2385 changes, the end of the RESULT_DECL handling block in
2386 use_register_for_decl must be adjusted to match. */
2387
2388 DECL_CHAIN (decl) = all->orig_fnargs;
2389 all->orig_fnargs = decl;
2390 fnargs.safe_insert (0, decl);
2391
2392 all->function_result_decl = decl;
2393 }
2394
2395 /* If the target wants to split complex arguments into scalars, do so. */
2396 if (targetm.calls.split_complex_arg)
2397 split_complex_args (&fnargs);
2398
2399 return fnargs;
2400 }
2401
2402 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2403 data for the parameter. Incorporate ABI specifics such as pass-by-
2404 reference and type promotion. */
2405
2406 static void
2407 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2408 struct assign_parm_data_one *data)
2409 {
2410 tree nominal_type, passed_type;
2411 machine_mode nominal_mode, passed_mode, promoted_mode;
2412 int unsignedp;
2413
2414 memset (data, 0, sizeof (*data));
2415
2416 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2417 if (!cfun->stdarg)
2418 data->named_arg = 1; /* No variadic parms. */
2419 else if (DECL_CHAIN (parm))
2420 data->named_arg = 1; /* Not the last non-variadic parm. */
2421 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2422 data->named_arg = 1; /* Only variadic ones are unnamed. */
2423 else
2424 data->named_arg = 0; /* Treat as variadic. */
2425
2426 nominal_type = TREE_TYPE (parm);
2427 passed_type = DECL_ARG_TYPE (parm);
2428
2429 /* Look out for errors propagating this far. Also, if the parameter's
2430 type is void then its value doesn't matter. */
2431 if (TREE_TYPE (parm) == error_mark_node
2432 /* This can happen after weird syntax errors
2433 or if an enum type is defined among the parms. */
2434 || TREE_CODE (parm) != PARM_DECL
2435 || passed_type == NULL
2436 || VOID_TYPE_P (nominal_type))
2437 {
2438 nominal_type = passed_type = void_type_node;
2439 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2440 goto egress;
2441 }
2442
2443 /* Find mode of arg as it is passed, and mode of arg as it should be
2444 during execution of this function. */
2445 passed_mode = TYPE_MODE (passed_type);
2446 nominal_mode = TYPE_MODE (nominal_type);
2447
2448 /* If the parm is to be passed as a transparent union or record, use the
2449 type of the first field for the tests below. We have already verified
2450 that the modes are the same. */
2451 if ((TREE_CODE (passed_type) == UNION_TYPE
2452 || TREE_CODE (passed_type) == RECORD_TYPE)
2453 && TYPE_TRANSPARENT_AGGR (passed_type))
2454 passed_type = TREE_TYPE (first_field (passed_type));
2455
2456 /* See if this arg was passed by invisible reference. */
2457 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2458 passed_type, data->named_arg))
2459 {
2460 passed_type = nominal_type = build_pointer_type (passed_type);
2461 data->passed_pointer = true;
2462 passed_mode = nominal_mode = TYPE_MODE (nominal_type);
2463 }
2464
2465 /* Find mode as it is passed by the ABI. */
2466 unsignedp = TYPE_UNSIGNED (passed_type);
2467 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2468 TREE_TYPE (current_function_decl), 0);
2469
2470 egress:
2471 data->nominal_type = nominal_type;
2472 data->passed_type = passed_type;
2473 data->nominal_mode = nominal_mode;
2474 data->passed_mode = passed_mode;
2475 data->promoted_mode = promoted_mode;
2476 }
2477
2478 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2479
2480 static void
2481 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2482 struct assign_parm_data_one *data, bool no_rtl)
2483 {
2484 int varargs_pretend_bytes = 0;
2485
2486 targetm.calls.setup_incoming_varargs (all->args_so_far,
2487 data->promoted_mode,
2488 data->passed_type,
2489 &varargs_pretend_bytes, no_rtl);
2490
2491 /* If the back-end has requested extra stack space, record how much is
2492 needed. Do not change pretend_args_size otherwise since it may be
2493 nonzero from an earlier partial argument. */
2494 if (varargs_pretend_bytes > 0)
2495 all->pretend_args_size = varargs_pretend_bytes;
2496 }
2497
2498 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2499 the incoming location of the current parameter. */
2500
2501 static void
2502 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2503 struct assign_parm_data_one *data)
2504 {
2505 HOST_WIDE_INT pretend_bytes = 0;
2506 rtx entry_parm;
2507 bool in_regs;
2508
2509 if (data->promoted_mode == VOIDmode)
2510 {
2511 data->entry_parm = data->stack_parm = const0_rtx;
2512 return;
2513 }
2514
2515 targetm.calls.warn_parameter_passing_abi (all->args_so_far,
2516 data->passed_type);
2517
2518 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2519 data->promoted_mode,
2520 data->passed_type,
2521 data->named_arg);
2522
2523 if (entry_parm == 0)
2524 data->promoted_mode = data->passed_mode;
2525
2526 /* Determine parm's home in the stack, in case it arrives in the stack
2527 or we should pretend it did. Compute the stack position and rtx where
2528 the argument arrives and its size.
2529
2530 There is one complexity here: If this was a parameter that would
2531 have been passed in registers, but wasn't only because it is
2532 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2533 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2534 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2535 as it was the previous time. */
2536 in_regs = (entry_parm != 0);
2537 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2538 in_regs = true;
2539 #endif
2540 if (!in_regs && !data->named_arg)
2541 {
2542 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2543 {
2544 rtx tem;
2545 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2546 data->promoted_mode,
2547 data->passed_type, true);
2548 in_regs = tem != NULL;
2549 }
2550 }
2551
2552 /* If this parameter was passed both in registers and in the stack, use
2553 the copy on the stack. */
2554 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2555 data->passed_type))
2556 entry_parm = 0;
2557
2558 if (entry_parm)
2559 {
2560 int partial;
2561
2562 function_arg_info arg (data->passed_type, data->promoted_mode,
2563 data->named_arg);
2564 partial = targetm.calls.arg_partial_bytes (all->args_so_far, arg);
2565 data->partial = partial;
2566
2567 /* The caller might already have allocated stack space for the
2568 register parameters. */
2569 if (partial != 0 && all->reg_parm_stack_space == 0)
2570 {
2571 /* Part of this argument is passed in registers and part
2572 is passed on the stack. Ask the prologue code to extend
2573 the stack part so that we can recreate the full value.
2574
2575 PRETEND_BYTES is the size of the registers we need to store.
2576 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2577 stack space that the prologue should allocate.
2578
2579 Internally, gcc assumes that the argument pointer is aligned
2580 to STACK_BOUNDARY bits. This is used both for alignment
2581 optimizations (see init_emit) and to locate arguments that are
2582 aligned to more than PARM_BOUNDARY bits. We must preserve this
2583 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2584 a stack boundary. */
2585
2586 /* We assume at most one partial arg, and it must be the first
2587 argument on the stack. */
2588 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2589
2590 pretend_bytes = partial;
2591 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2592
2593 /* We want to align relative to the actual stack pointer, so
2594 don't include this in the stack size until later. */
2595 all->extra_pretend_bytes = all->pretend_args_size;
2596 }
2597 }
2598
2599 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2600 all->reg_parm_stack_space,
2601 entry_parm ? data->partial : 0, current_function_decl,
2602 &all->stack_args_size, &data->locate);
2603
2604 /* Update parm_stack_boundary if this parameter is passed in the
2605 stack. */
2606 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2607 crtl->parm_stack_boundary = data->locate.boundary;
2608
2609 /* Adjust offsets to include the pretend args. */
2610 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2611 data->locate.slot_offset.constant += pretend_bytes;
2612 data->locate.offset.constant += pretend_bytes;
2613
2614 data->entry_parm = entry_parm;
2615 }
2616
2617 /* A subroutine of assign_parms. If there is actually space on the stack
2618 for this parm, count it in stack_args_size and return true. */
2619
2620 static bool
2621 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2622 struct assign_parm_data_one *data)
2623 {
2624 /* Trivially true if we've no incoming register. */
2625 if (data->entry_parm == NULL)
2626 ;
2627 /* Also true if we're partially in registers and partially not,
2628 since we've arranged to drop the entire argument on the stack. */
2629 else if (data->partial != 0)
2630 ;
2631 /* Also true if the target says that it's passed in both registers
2632 and on the stack. */
2633 else if (GET_CODE (data->entry_parm) == PARALLEL
2634 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2635 ;
2636 /* Also true if the target says that there's stack allocated for
2637 all register parameters. */
2638 else if (all->reg_parm_stack_space > 0)
2639 ;
2640 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2641 else
2642 return false;
2643
2644 all->stack_args_size.constant += data->locate.size.constant;
2645 if (data->locate.size.var)
2646 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2647
2648 return true;
2649 }
2650
2651 /* A subroutine of assign_parms. Given that this parameter is allocated
2652 stack space by the ABI, find it. */
2653
2654 static void
2655 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2656 {
2657 rtx offset_rtx, stack_parm;
2658 unsigned int align, boundary;
2659
2660 /* If we're passing this arg using a reg, make its stack home the
2661 aligned stack slot. */
2662 if (data->entry_parm)
2663 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2664 else
2665 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2666
2667 stack_parm = crtl->args.internal_arg_pointer;
2668 if (offset_rtx != const0_rtx)
2669 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2670 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2671
2672 if (!data->passed_pointer)
2673 {
2674 set_mem_attributes (stack_parm, parm, 1);
2675 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2676 while promoted mode's size is needed. */
2677 if (data->promoted_mode != BLKmode
2678 && data->promoted_mode != DECL_MODE (parm))
2679 {
2680 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2681 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2682 {
2683 poly_int64 offset = subreg_lowpart_offset (DECL_MODE (parm),
2684 data->promoted_mode);
2685 if (maybe_ne (offset, 0))
2686 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2687 }
2688 }
2689 }
2690
2691 boundary = data->locate.boundary;
2692 align = BITS_PER_UNIT;
2693
2694 /* If we're padding upward, we know that the alignment of the slot
2695 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2696 intentionally forcing upward padding. Otherwise we have to come
2697 up with a guess at the alignment based on OFFSET_RTX. */
2698 poly_int64 offset;
2699 if (data->locate.where_pad == PAD_NONE || data->entry_parm)
2700 align = boundary;
2701 else if (data->locate.where_pad == PAD_UPWARD)
2702 {
2703 align = boundary;
2704 /* If the argument offset is actually more aligned than the nominal
2705 stack slot boundary, take advantage of that excess alignment.
2706 Don't make any assumptions if STACK_POINTER_OFFSET is in use. */
2707 if (poly_int_rtx_p (offset_rtx, &offset)
2708 && STACK_POINTER_OFFSET == 0)
2709 {
2710 unsigned int offset_align = known_alignment (offset) * BITS_PER_UNIT;
2711 if (offset_align == 0 || offset_align > STACK_BOUNDARY)
2712 offset_align = STACK_BOUNDARY;
2713 align = MAX (align, offset_align);
2714 }
2715 }
2716 else if (poly_int_rtx_p (offset_rtx, &offset))
2717 {
2718 align = least_bit_hwi (boundary);
2719 unsigned int offset_align = known_alignment (offset) * BITS_PER_UNIT;
2720 if (offset_align != 0)
2721 align = MIN (align, offset_align);
2722 }
2723 set_mem_align (stack_parm, align);
2724
2725 if (data->entry_parm)
2726 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2727
2728 data->stack_parm = stack_parm;
2729 }
2730
2731 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2732 always valid and contiguous. */
2733
2734 static void
2735 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2736 {
2737 rtx entry_parm = data->entry_parm;
2738 rtx stack_parm = data->stack_parm;
2739
2740 /* If this parm was passed part in regs and part in memory, pretend it
2741 arrived entirely in memory by pushing the register-part onto the stack.
2742 In the special case of a DImode or DFmode that is split, we could put
2743 it together in a pseudoreg directly, but for now that's not worth
2744 bothering with. */
2745 if (data->partial != 0)
2746 {
2747 /* Handle calls that pass values in multiple non-contiguous
2748 locations. The Irix 6 ABI has examples of this. */
2749 if (GET_CODE (entry_parm) == PARALLEL)
2750 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2751 data->passed_type,
2752 int_size_in_bytes (data->passed_type));
2753 else
2754 {
2755 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2756 move_block_from_reg (REGNO (entry_parm),
2757 validize_mem (copy_rtx (stack_parm)),
2758 data->partial / UNITS_PER_WORD);
2759 }
2760
2761 entry_parm = stack_parm;
2762 }
2763
2764 /* If we didn't decide this parm came in a register, by default it came
2765 on the stack. */
2766 else if (entry_parm == NULL)
2767 entry_parm = stack_parm;
2768
2769 /* When an argument is passed in multiple locations, we can't make use
2770 of this information, but we can save some copying if the whole argument
2771 is passed in a single register. */
2772 else if (GET_CODE (entry_parm) == PARALLEL
2773 && data->nominal_mode != BLKmode
2774 && data->passed_mode != BLKmode)
2775 {
2776 size_t i, len = XVECLEN (entry_parm, 0);
2777
2778 for (i = 0; i < len; i++)
2779 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2780 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2781 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2782 == data->passed_mode)
2783 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2784 {
2785 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2786 break;
2787 }
2788 }
2789
2790 data->entry_parm = entry_parm;
2791 }
2792
2793 /* A subroutine of assign_parms. Reconstitute any values which were
2794 passed in multiple registers and would fit in a single register. */
2795
2796 static void
2797 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2798 {
2799 rtx entry_parm = data->entry_parm;
2800
2801 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2802 This can be done with register operations rather than on the
2803 stack, even if we will store the reconstituted parameter on the
2804 stack later. */
2805 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2806 {
2807 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2808 emit_group_store (parmreg, entry_parm, data->passed_type,
2809 GET_MODE_SIZE (GET_MODE (entry_parm)));
2810 entry_parm = parmreg;
2811 }
2812
2813 data->entry_parm = entry_parm;
2814 }
2815
2816 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2817 always valid and properly aligned. */
2818
2819 static void
2820 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2821 {
2822 rtx stack_parm = data->stack_parm;
2823
2824 /* If we can't trust the parm stack slot to be aligned enough for its
2825 ultimate type, don't use that slot after entry. We'll make another
2826 stack slot, if we need one. */
2827 if (stack_parm
2828 && ((GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm)
2829 && targetm.slow_unaligned_access (data->nominal_mode,
2830 MEM_ALIGN (stack_parm)))
2831 || (data->nominal_type
2832 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2833 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2834 stack_parm = NULL;
2835
2836 /* If parm was passed in memory, and we need to convert it on entry,
2837 don't store it back in that same slot. */
2838 else if (data->entry_parm == stack_parm
2839 && data->nominal_mode != BLKmode
2840 && data->nominal_mode != data->passed_mode)
2841 stack_parm = NULL;
2842
2843 /* If stack protection is in effect for this function, don't leave any
2844 pointers in their passed stack slots. */
2845 else if (crtl->stack_protect_guard
2846 && (flag_stack_protect == 2
2847 || data->passed_pointer
2848 || POINTER_TYPE_P (data->nominal_type)))
2849 stack_parm = NULL;
2850
2851 data->stack_parm = stack_parm;
2852 }
2853
2854 /* A subroutine of assign_parms. Return true if the current parameter
2855 should be stored as a BLKmode in the current frame. */
2856
2857 static bool
2858 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2859 {
2860 if (data->nominal_mode == BLKmode)
2861 return true;
2862 if (GET_MODE (data->entry_parm) == BLKmode)
2863 return true;
2864
2865 #ifdef BLOCK_REG_PADDING
2866 /* Only assign_parm_setup_block knows how to deal with register arguments
2867 that are padded at the least significant end. */
2868 if (REG_P (data->entry_parm)
2869 && known_lt (GET_MODE_SIZE (data->promoted_mode), UNITS_PER_WORD)
2870 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2871 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2872 return true;
2873 #endif
2874
2875 return false;
2876 }
2877
2878 /* A subroutine of assign_parms. Arrange for the parameter to be
2879 present and valid in DATA->STACK_RTL. */
2880
2881 static void
2882 assign_parm_setup_block (struct assign_parm_data_all *all,
2883 tree parm, struct assign_parm_data_one *data)
2884 {
2885 rtx entry_parm = data->entry_parm;
2886 rtx stack_parm = data->stack_parm;
2887 rtx target_reg = NULL_RTX;
2888 bool in_conversion_seq = false;
2889 HOST_WIDE_INT size;
2890 HOST_WIDE_INT size_stored;
2891
2892 if (GET_CODE (entry_parm) == PARALLEL)
2893 entry_parm = emit_group_move_into_temps (entry_parm);
2894
2895 /* If we want the parameter in a pseudo, don't use a stack slot. */
2896 if (is_gimple_reg (parm) && use_register_for_decl (parm))
2897 {
2898 tree def = ssa_default_def (cfun, parm);
2899 gcc_assert (def);
2900 machine_mode mode = promote_ssa_mode (def, NULL);
2901 rtx reg = gen_reg_rtx (mode);
2902 if (GET_CODE (reg) != CONCAT)
2903 stack_parm = reg;
2904 else
2905 {
2906 target_reg = reg;
2907 /* Avoid allocating a stack slot, if there isn't one
2908 preallocated by the ABI. It might seem like we should
2909 always prefer a pseudo, but converting between
2910 floating-point and integer modes goes through the stack
2911 on various machines, so it's better to use the reserved
2912 stack slot than to risk wasting it and allocating more
2913 for the conversion. */
2914 if (stack_parm == NULL_RTX)
2915 {
2916 int save = generating_concat_p;
2917 generating_concat_p = 0;
2918 stack_parm = gen_reg_rtx (mode);
2919 generating_concat_p = save;
2920 }
2921 }
2922 data->stack_parm = NULL;
2923 }
2924
2925 size = int_size_in_bytes (data->passed_type);
2926 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2927 if (stack_parm == 0)
2928 {
2929 HOST_WIDE_INT parm_align
2930 = (STRICT_ALIGNMENT
2931 ? MAX (DECL_ALIGN (parm), BITS_PER_WORD) : DECL_ALIGN (parm));
2932
2933 SET_DECL_ALIGN (parm, parm_align);
2934 if (DECL_ALIGN (parm) > MAX_SUPPORTED_STACK_ALIGNMENT)
2935 {
2936 rtx allocsize = gen_int_mode (size_stored, Pmode);
2937 get_dynamic_stack_size (&allocsize, 0, DECL_ALIGN (parm), NULL);
2938 stack_parm = assign_stack_local (BLKmode, UINTVAL (allocsize),
2939 MAX_SUPPORTED_STACK_ALIGNMENT);
2940 rtx addr = align_dynamic_address (XEXP (stack_parm, 0),
2941 DECL_ALIGN (parm));
2942 mark_reg_pointer (addr, DECL_ALIGN (parm));
2943 stack_parm = gen_rtx_MEM (GET_MODE (stack_parm), addr);
2944 MEM_NOTRAP_P (stack_parm) = 1;
2945 }
2946 else
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)
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
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 enum insn_code icode;
3145 rtx rtl;
3146
3147 /* Store the parm in a pseudoregister during the function, but we may
3148 need to do it in a wider mode. Using 2 here makes the result
3149 consistent with promote_decl_mode and thus expand_expr_real_1. */
3150 promoted_nominal_mode
3151 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
3152 TREE_TYPE (current_function_decl), 2);
3153
3154 parmreg = gen_reg_rtx (promoted_nominal_mode);
3155 if (!DECL_ARTIFICIAL (parm))
3156 mark_user_reg (parmreg);
3157
3158 /* If this was an item that we received a pointer to,
3159 set rtl appropriately. */
3160 if (data->passed_pointer)
3161 {
3162 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
3163 set_mem_attributes (rtl, parm, 1);
3164 }
3165 else
3166 rtl = parmreg;
3167
3168 assign_parm_remove_parallels (data);
3169
3170 /* Copy the value into the register, thus bridging between
3171 assign_parm_find_data_types and expand_expr_real_1. */
3172
3173 equiv_stack_parm = data->stack_parm;
3174 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3175
3176 need_conversion = (data->nominal_mode != data->passed_mode
3177 || promoted_nominal_mode != data->promoted_mode);
3178 moved = false;
3179
3180 if (need_conversion
3181 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3182 && data->nominal_mode == data->passed_mode
3183 && data->nominal_mode == GET_MODE (data->entry_parm))
3184 {
3185 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3186 mode, by the caller. We now have to convert it to
3187 NOMINAL_MODE, if different. However, PARMREG may be in
3188 a different mode than NOMINAL_MODE if it is being stored
3189 promoted.
3190
3191 If ENTRY_PARM is a hard register, it might be in a register
3192 not valid for operating in its mode (e.g., an odd-numbered
3193 register for a DFmode). In that case, moves are the only
3194 thing valid, so we can't do a convert from there. This
3195 occurs when the calling sequence allow such misaligned
3196 usages.
3197
3198 In addition, the conversion may involve a call, which could
3199 clobber parameters which haven't been copied to pseudo
3200 registers yet.
3201
3202 First, we try to emit an insn which performs the necessary
3203 conversion. We verify that this insn does not clobber any
3204 hard registers. */
3205
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 if (MEM_P (data->entry_parm)
3309 && GET_MODE_ALIGNMENT (promoted_nominal_mode)
3310 > MEM_ALIGN (data->entry_parm)
3311 && (((icode = optab_handler (movmisalign_optab,
3312 promoted_nominal_mode))
3313 != CODE_FOR_nothing)
3314 || targetm.slow_unaligned_access (promoted_nominal_mode,
3315 MEM_ALIGN (data->entry_parm))))
3316 {
3317 if (icode != CODE_FOR_nothing)
3318 emit_insn (GEN_FCN (icode) (parmreg, validated_mem));
3319 else
3320 rtl = parmreg = extract_bit_field (validated_mem,
3321 GET_MODE_BITSIZE (promoted_nominal_mode), 0,
3322 unsignedp, parmreg,
3323 promoted_nominal_mode, VOIDmode, false, NULL);
3324 }
3325 else
3326 emit_move_insn (parmreg, validated_mem);
3327
3328 /* If we were passed a pointer but the actual value can safely live
3329 in a register, retrieve it and use it directly. */
3330 if (data->passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3331 {
3332 /* We can't use nominal_mode, because it will have been set to
3333 Pmode above. We must use the actual mode of the parm. */
3334 if (use_register_for_decl (parm))
3335 {
3336 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3337 mark_user_reg (parmreg);
3338 }
3339 else
3340 {
3341 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3342 TYPE_MODE (TREE_TYPE (parm)),
3343 TYPE_ALIGN (TREE_TYPE (parm)));
3344 parmreg
3345 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3346 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3347 align);
3348 set_mem_attributes (parmreg, parm, 1);
3349 }
3350
3351 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3352 the debug info in case it is not legitimate. */
3353 if (GET_MODE (parmreg) != GET_MODE (rtl))
3354 {
3355 rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
3356 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3357
3358 push_to_sequence2 (all->first_conversion_insn,
3359 all->last_conversion_insn);
3360 emit_move_insn (tempreg, rtl);
3361 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3362 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
3363 tempreg);
3364 all->first_conversion_insn = get_insns ();
3365 all->last_conversion_insn = get_last_insn ();
3366 end_sequence ();
3367
3368 did_conversion = true;
3369 }
3370 else
3371 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
3372
3373 rtl = parmreg;
3374
3375 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3376 now the parm. */
3377 data->stack_parm = NULL;
3378 }
3379
3380 set_parm_rtl (parm, rtl);
3381
3382 /* Mark the register as eliminable if we did no conversion and it was
3383 copied from memory at a fixed offset, and the arg pointer was not
3384 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3385 offset formed an invalid address, such memory-equivalences as we
3386 make here would screw up life analysis for it. */
3387 if (data->nominal_mode == data->passed_mode
3388 && !did_conversion
3389 && data->stack_parm != 0
3390 && MEM_P (data->stack_parm)
3391 && data->locate.offset.var == 0
3392 && reg_mentioned_p (virtual_incoming_args_rtx,
3393 XEXP (data->stack_parm, 0)))
3394 {
3395 rtx_insn *linsn = get_last_insn ();
3396 rtx_insn *sinsn;
3397 rtx set;
3398
3399 /* Mark complex types separately. */
3400 if (GET_CODE (parmreg) == CONCAT)
3401 {
3402 scalar_mode submode = GET_MODE_INNER (GET_MODE (parmreg));
3403 int regnor = REGNO (XEXP (parmreg, 0));
3404 int regnoi = REGNO (XEXP (parmreg, 1));
3405 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3406 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3407 GET_MODE_SIZE (submode));
3408
3409 /* Scan backwards for the set of the real and
3410 imaginary parts. */
3411 for (sinsn = linsn; sinsn != 0;
3412 sinsn = prev_nonnote_insn (sinsn))
3413 {
3414 set = single_set (sinsn);
3415 if (set == 0)
3416 continue;
3417
3418 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3419 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3420 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3421 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3422 }
3423 }
3424 else
3425 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3426 }
3427
3428 /* For pointer data type, suggest pointer register. */
3429 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3430 mark_reg_pointer (parmreg,
3431 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3432 }
3433
3434 /* A subroutine of assign_parms. Allocate stack space to hold the current
3435 parameter. Get it there. Perform all ABI specified conversions. */
3436
3437 static void
3438 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3439 struct assign_parm_data_one *data)
3440 {
3441 /* Value must be stored in the stack slot STACK_PARM during function
3442 execution. */
3443 bool to_conversion = false;
3444
3445 assign_parm_remove_parallels (data);
3446
3447 if (data->promoted_mode != data->nominal_mode)
3448 {
3449 /* Conversion is required. */
3450 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3451
3452 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3453
3454 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3455 to_conversion = true;
3456
3457 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3458 TYPE_UNSIGNED (TREE_TYPE (parm)));
3459
3460 if (data->stack_parm)
3461 {
3462 poly_int64 offset
3463 = subreg_lowpart_offset (data->nominal_mode,
3464 GET_MODE (data->stack_parm));
3465 /* ??? This may need a big-endian conversion on sparc64. */
3466 data->stack_parm
3467 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3468 if (maybe_ne (offset, 0) && MEM_OFFSET_KNOWN_P (data->stack_parm))
3469 set_mem_offset (data->stack_parm,
3470 MEM_OFFSET (data->stack_parm) + offset);
3471 }
3472 }
3473
3474 if (data->entry_parm != data->stack_parm)
3475 {
3476 rtx src, dest;
3477
3478 if (data->stack_parm == 0)
3479 {
3480 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3481 GET_MODE (data->entry_parm),
3482 TYPE_ALIGN (data->passed_type));
3483 data->stack_parm
3484 = assign_stack_local (GET_MODE (data->entry_parm),
3485 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3486 align);
3487 set_mem_attributes (data->stack_parm, parm, 1);
3488 }
3489
3490 dest = validize_mem (copy_rtx (data->stack_parm));
3491 src = validize_mem (copy_rtx (data->entry_parm));
3492
3493 if (MEM_P (src))
3494 {
3495 /* Use a block move to handle potentially misaligned entry_parm. */
3496 if (!to_conversion)
3497 push_to_sequence2 (all->first_conversion_insn,
3498 all->last_conversion_insn);
3499 to_conversion = true;
3500
3501 emit_block_move (dest, src,
3502 GEN_INT (int_size_in_bytes (data->passed_type)),
3503 BLOCK_OP_NORMAL);
3504 }
3505 else
3506 {
3507 if (!REG_P (src))
3508 src = force_reg (GET_MODE (src), src);
3509 emit_move_insn (dest, src);
3510 }
3511 }
3512
3513 if (to_conversion)
3514 {
3515 all->first_conversion_insn = get_insns ();
3516 all->last_conversion_insn = get_last_insn ();
3517 end_sequence ();
3518 }
3519
3520 set_parm_rtl (parm, data->stack_parm);
3521 }
3522
3523 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3524 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3525
3526 static void
3527 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3528 vec<tree> fnargs)
3529 {
3530 tree parm;
3531 tree orig_fnargs = all->orig_fnargs;
3532 unsigned i = 0;
3533
3534 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3535 {
3536 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3537 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3538 {
3539 rtx tmp, real, imag;
3540 scalar_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3541
3542 real = DECL_RTL (fnargs[i]);
3543 imag = DECL_RTL (fnargs[i + 1]);
3544 if (inner != GET_MODE (real))
3545 {
3546 real = gen_lowpart_SUBREG (inner, real);
3547 imag = gen_lowpart_SUBREG (inner, imag);
3548 }
3549
3550 if (TREE_ADDRESSABLE (parm))
3551 {
3552 rtx rmem, imem;
3553 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3554 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3555 DECL_MODE (parm),
3556 TYPE_ALIGN (TREE_TYPE (parm)));
3557
3558 /* split_complex_arg put the real and imag parts in
3559 pseudos. Move them to memory. */
3560 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3561 set_mem_attributes (tmp, parm, 1);
3562 rmem = adjust_address_nv (tmp, inner, 0);
3563 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3564 push_to_sequence2 (all->first_conversion_insn,
3565 all->last_conversion_insn);
3566 emit_move_insn (rmem, real);
3567 emit_move_insn (imem, imag);
3568 all->first_conversion_insn = get_insns ();
3569 all->last_conversion_insn = get_last_insn ();
3570 end_sequence ();
3571 }
3572 else
3573 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3574 set_parm_rtl (parm, tmp);
3575
3576 real = DECL_INCOMING_RTL (fnargs[i]);
3577 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3578 if (inner != GET_MODE (real))
3579 {
3580 real = gen_lowpart_SUBREG (inner, real);
3581 imag = gen_lowpart_SUBREG (inner, imag);
3582 }
3583 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3584 set_decl_incoming_rtl (parm, tmp, false);
3585 i++;
3586 }
3587 }
3588 }
3589
3590 /* Assign RTL expressions to the function's parameters. This may involve
3591 copying them into registers and using those registers as the DECL_RTL. */
3592
3593 static void
3594 assign_parms (tree fndecl)
3595 {
3596 struct assign_parm_data_all all;
3597 tree parm;
3598 vec<tree> fnargs;
3599 unsigned i;
3600
3601 crtl->args.internal_arg_pointer
3602 = targetm.calls.internal_arg_pointer ();
3603
3604 assign_parms_initialize_all (&all);
3605 fnargs = assign_parms_augmented_arg_list (&all);
3606
3607 FOR_EACH_VEC_ELT (fnargs, i, parm)
3608 {
3609 struct assign_parm_data_one data;
3610
3611 /* Extract the type of PARM; adjust it according to ABI. */
3612 assign_parm_find_data_types (&all, parm, &data);
3613
3614 /* Early out for errors and void parameters. */
3615 if (data.passed_mode == VOIDmode)
3616 {
3617 SET_DECL_RTL (parm, const0_rtx);
3618 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3619 continue;
3620 }
3621
3622 /* Estimate stack alignment from parameter alignment. */
3623 if (SUPPORTS_STACK_ALIGNMENT)
3624 {
3625 unsigned int align
3626 = targetm.calls.function_arg_boundary (data.promoted_mode,
3627 data.passed_type);
3628 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3629 align);
3630 if (TYPE_ALIGN (data.nominal_type) > align)
3631 align = MINIMUM_ALIGNMENT (data.nominal_type,
3632 TYPE_MODE (data.nominal_type),
3633 TYPE_ALIGN (data.nominal_type));
3634 if (crtl->stack_alignment_estimated < align)
3635 {
3636 gcc_assert (!crtl->stack_realign_processed);
3637 crtl->stack_alignment_estimated = align;
3638 }
3639 }
3640
3641 /* Find out where the parameter arrives in this function. */
3642 assign_parm_find_entry_rtl (&all, &data);
3643
3644 /* Find out where stack space for this parameter might be. */
3645 if (assign_parm_is_stack_parm (&all, &data))
3646 {
3647 assign_parm_find_stack_rtl (parm, &data);
3648 assign_parm_adjust_entry_rtl (&data);
3649 }
3650 /* Record permanently how this parm was passed. */
3651 if (data.passed_pointer)
3652 {
3653 rtx incoming_rtl
3654 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3655 data.entry_parm);
3656 set_decl_incoming_rtl (parm, incoming_rtl, true);
3657 }
3658 else
3659 set_decl_incoming_rtl (parm, data.entry_parm, false);
3660
3661 assign_parm_adjust_stack_rtl (&data);
3662
3663 if (assign_parm_setup_block_p (&data))
3664 assign_parm_setup_block (&all, parm, &data);
3665 else if (data.passed_pointer || use_register_for_decl (parm))
3666 assign_parm_setup_reg (&all, parm, &data);
3667 else
3668 assign_parm_setup_stack (&all, parm, &data);
3669
3670 if (cfun->stdarg && !DECL_CHAIN (parm))
3671 assign_parms_setup_varargs (&all, &data, false);
3672
3673 /* Update info on where next arg arrives in registers. */
3674 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3675 data.passed_type, data.named_arg);
3676 }
3677
3678 if (targetm.calls.split_complex_arg)
3679 assign_parms_unsplit_complex (&all, fnargs);
3680
3681 fnargs.release ();
3682
3683 /* Output all parameter conversion instructions (possibly including calls)
3684 now that all parameters have been copied out of hard registers. */
3685 emit_insn (all.first_conversion_insn);
3686
3687 /* Estimate reload stack alignment from scalar return mode. */
3688 if (SUPPORTS_STACK_ALIGNMENT)
3689 {
3690 if (DECL_RESULT (fndecl))
3691 {
3692 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3693 machine_mode mode = TYPE_MODE (type);
3694
3695 if (mode != BLKmode
3696 && mode != VOIDmode
3697 && !AGGREGATE_TYPE_P (type))
3698 {
3699 unsigned int align = GET_MODE_ALIGNMENT (mode);
3700 if (crtl->stack_alignment_estimated < align)
3701 {
3702 gcc_assert (!crtl->stack_realign_processed);
3703 crtl->stack_alignment_estimated = align;
3704 }
3705 }
3706 }
3707 }
3708
3709 /* If we are receiving a struct value address as the first argument, set up
3710 the RTL for the function result. As this might require code to convert
3711 the transmitted address to Pmode, we do this here to ensure that possible
3712 preliminary conversions of the address have been emitted already. */
3713 if (all.function_result_decl)
3714 {
3715 tree result = DECL_RESULT (current_function_decl);
3716 rtx addr = DECL_RTL (all.function_result_decl);
3717 rtx x;
3718
3719 if (DECL_BY_REFERENCE (result))
3720 {
3721 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3722 x = addr;
3723 }
3724 else
3725 {
3726 SET_DECL_VALUE_EXPR (result,
3727 build1 (INDIRECT_REF, TREE_TYPE (result),
3728 all.function_result_decl));
3729 addr = convert_memory_address (Pmode, addr);
3730 x = gen_rtx_MEM (DECL_MODE (result), addr);
3731 set_mem_attributes (x, result, 1);
3732 }
3733
3734 DECL_HAS_VALUE_EXPR_P (result) = 1;
3735
3736 set_parm_rtl (result, x);
3737 }
3738
3739 /* We have aligned all the args, so add space for the pretend args. */
3740 crtl->args.pretend_args_size = all.pretend_args_size;
3741 all.stack_args_size.constant += all.extra_pretend_bytes;
3742 crtl->args.size = all.stack_args_size.constant;
3743
3744 /* Adjust function incoming argument size for alignment and
3745 minimum length. */
3746
3747 crtl->args.size = upper_bound (crtl->args.size, all.reg_parm_stack_space);
3748 crtl->args.size = aligned_upper_bound (crtl->args.size,
3749 PARM_BOUNDARY / BITS_PER_UNIT);
3750
3751 if (ARGS_GROW_DOWNWARD)
3752 {
3753 crtl->args.arg_offset_rtx
3754 = (all.stack_args_size.var == 0
3755 ? gen_int_mode (-all.stack_args_size.constant, Pmode)
3756 : expand_expr (size_diffop (all.stack_args_size.var,
3757 size_int (-all.stack_args_size.constant)),
3758 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3759 }
3760 else
3761 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3762
3763 /* See how many bytes, if any, of its args a function should try to pop
3764 on return. */
3765
3766 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3767 TREE_TYPE (fndecl),
3768 crtl->args.size);
3769
3770 /* For stdarg.h function, save info about
3771 regs and stack space used by the named args. */
3772
3773 crtl->args.info = all.args_so_far_v;
3774
3775 /* Set the rtx used for the function return value. Put this in its
3776 own variable so any optimizers that need this information don't have
3777 to include tree.h. Do this here so it gets done when an inlined
3778 function gets output. */
3779
3780 crtl->return_rtx
3781 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3782 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3783
3784 /* If scalar return value was computed in a pseudo-reg, or was a named
3785 return value that got dumped to the stack, copy that to the hard
3786 return register. */
3787 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3788 {
3789 tree decl_result = DECL_RESULT (fndecl);
3790 rtx decl_rtl = DECL_RTL (decl_result);
3791
3792 if (REG_P (decl_rtl)
3793 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3794 : DECL_REGISTER (decl_result))
3795 {
3796 rtx real_decl_rtl;
3797
3798 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3799 fndecl, true);
3800 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3801 /* The delay slot scheduler assumes that crtl->return_rtx
3802 holds the hard register containing the return value, not a
3803 temporary pseudo. */
3804 crtl->return_rtx = real_decl_rtl;
3805 }
3806 }
3807 }
3808
3809 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3810 For all seen types, gimplify their sizes. */
3811
3812 static tree
3813 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3814 {
3815 tree t = *tp;
3816
3817 *walk_subtrees = 0;
3818 if (TYPE_P (t))
3819 {
3820 if (POINTER_TYPE_P (t))
3821 *walk_subtrees = 1;
3822 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3823 && !TYPE_SIZES_GIMPLIFIED (t))
3824 {
3825 gimplify_type_sizes (t, (gimple_seq *) data);
3826 *walk_subtrees = 1;
3827 }
3828 }
3829
3830 return NULL;
3831 }
3832
3833 /* Gimplify the parameter list for current_function_decl. This involves
3834 evaluating SAVE_EXPRs of variable sized parameters and generating code
3835 to implement callee-copies reference parameters. Returns a sequence of
3836 statements to add to the beginning of the function. */
3837
3838 gimple_seq
3839 gimplify_parameters (gimple_seq *cleanup)
3840 {
3841 struct assign_parm_data_all all;
3842 tree parm;
3843 gimple_seq stmts = NULL;
3844 vec<tree> fnargs;
3845 unsigned i;
3846
3847 assign_parms_initialize_all (&all);
3848 fnargs = assign_parms_augmented_arg_list (&all);
3849
3850 FOR_EACH_VEC_ELT (fnargs, i, parm)
3851 {
3852 struct assign_parm_data_one data;
3853
3854 /* Extract the type of PARM; adjust it according to ABI. */
3855 assign_parm_find_data_types (&all, parm, &data);
3856
3857 /* Early out for errors and void parameters. */
3858 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3859 continue;
3860
3861 /* Update info on where next arg arrives in registers. */
3862 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3863 data.passed_type, data.named_arg);
3864
3865 /* ??? Once upon a time variable_size stuffed parameter list
3866 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3867 turned out to be less than manageable in the gimple world.
3868 Now we have to hunt them down ourselves. */
3869 walk_tree_without_duplicates (&data.passed_type,
3870 gimplify_parm_type, &stmts);
3871
3872 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3873 {
3874 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3875 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3876 }
3877
3878 if (data.passed_pointer)
3879 {
3880 tree type = TREE_TYPE (data.passed_type);
3881 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
3882 type, data.named_arg))
3883 {
3884 tree local, t;
3885
3886 /* For constant-sized objects, this is trivial; for
3887 variable-sized objects, we have to play games. */
3888 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3889 && !(flag_stack_check == GENERIC_STACK_CHECK
3890 && compare_tree_int (DECL_SIZE_UNIT (parm),
3891 STACK_CHECK_MAX_VAR_SIZE) > 0))
3892 {
3893 local = create_tmp_var (type, get_name (parm));
3894 DECL_IGNORED_P (local) = 0;
3895 /* If PARM was addressable, move that flag over
3896 to the local copy, as its address will be taken,
3897 not the PARMs. Keep the parms address taken
3898 as we'll query that flag during gimplification. */
3899 if (TREE_ADDRESSABLE (parm))
3900 TREE_ADDRESSABLE (local) = 1;
3901 else if (TREE_CODE (type) == COMPLEX_TYPE
3902 || TREE_CODE (type) == VECTOR_TYPE)
3903 DECL_GIMPLE_REG_P (local) = 1;
3904
3905 if (!is_gimple_reg (local)
3906 && flag_stack_reuse != SR_NONE)
3907 {
3908 tree clobber = build_constructor (type, NULL);
3909 gimple *clobber_stmt;
3910 TREE_THIS_VOLATILE (clobber) = 1;
3911 clobber_stmt = gimple_build_assign (local, clobber);
3912 gimple_seq_add_stmt (cleanup, clobber_stmt);
3913 }
3914 }
3915 else
3916 {
3917 tree ptr_type, addr;
3918
3919 ptr_type = build_pointer_type (type);
3920 addr = create_tmp_reg (ptr_type, get_name (parm));
3921 DECL_IGNORED_P (addr) = 0;
3922 local = build_fold_indirect_ref (addr);
3923
3924 t = build_alloca_call_expr (DECL_SIZE_UNIT (parm),
3925 DECL_ALIGN (parm),
3926 max_int_size_in_bytes (type));
3927 /* The call has been built for a variable-sized object. */
3928 CALL_ALLOCA_FOR_VAR_P (t) = 1;
3929 t = fold_convert (ptr_type, t);
3930 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3931 gimplify_and_add (t, &stmts);
3932 }
3933
3934 gimplify_assign (local, parm, &stmts);
3935
3936 SET_DECL_VALUE_EXPR (parm, local);
3937 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3938 }
3939 }
3940 }
3941
3942 fnargs.release ();
3943
3944 return stmts;
3945 }
3946 \f
3947 /* Compute the size and offset from the start of the stacked arguments for a
3948 parm passed in mode PASSED_MODE and with type TYPE.
3949
3950 INITIAL_OFFSET_PTR points to the current offset into the stacked
3951 arguments.
3952
3953 The starting offset and size for this parm are returned in
3954 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3955 nonzero, the offset is that of stack slot, which is returned in
3956 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3957 padding required from the initial offset ptr to the stack slot.
3958
3959 IN_REGS is nonzero if the argument will be passed in registers. It will
3960 never be set if REG_PARM_STACK_SPACE is not defined.
3961
3962 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3963 for arguments which are passed in registers.
3964
3965 FNDECL is the function in which the argument was defined.
3966
3967 There are two types of rounding that are done. The first, controlled by
3968 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3969 argument list to be aligned to the specific boundary (in bits). This
3970 rounding affects the initial and starting offsets, but not the argument
3971 size.
3972
3973 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3974 optionally rounds the size of the parm to PARM_BOUNDARY. The
3975 initial offset is not affected by this rounding, while the size always
3976 is and the starting offset may be. */
3977
3978 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3979 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3980 callers pass in the total size of args so far as
3981 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3982
3983 void
3984 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
3985 int reg_parm_stack_space, int partial,
3986 tree fndecl ATTRIBUTE_UNUSED,
3987 struct args_size *initial_offset_ptr,
3988 struct locate_and_pad_arg_data *locate)
3989 {
3990 tree sizetree;
3991 pad_direction where_pad;
3992 unsigned int boundary, round_boundary;
3993 int part_size_in_regs;
3994
3995 /* If we have found a stack parm before we reach the end of the
3996 area reserved for registers, skip that area. */
3997 if (! in_regs)
3998 {
3999 if (reg_parm_stack_space > 0)
4000 {
4001 if (initial_offset_ptr->var
4002 || !ordered_p (initial_offset_ptr->constant,
4003 reg_parm_stack_space))
4004 {
4005 initial_offset_ptr->var
4006 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4007 ssize_int (reg_parm_stack_space));
4008 initial_offset_ptr->constant = 0;
4009 }
4010 else
4011 initial_offset_ptr->constant
4012 = ordered_max (initial_offset_ptr->constant,
4013 reg_parm_stack_space);
4014 }
4015 }
4016
4017 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
4018
4019 sizetree = (type
4020 ? arg_size_in_bytes (type)
4021 : size_int (GET_MODE_SIZE (passed_mode)));
4022 where_pad = targetm.calls.function_arg_padding (passed_mode, type);
4023 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
4024 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
4025 type);
4026 locate->where_pad = where_pad;
4027
4028 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4029 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
4030 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
4031
4032 locate->boundary = boundary;
4033
4034 if (SUPPORTS_STACK_ALIGNMENT)
4035 {
4036 /* stack_alignment_estimated can't change after stack has been
4037 realigned. */
4038 if (crtl->stack_alignment_estimated < boundary)
4039 {
4040 if (!crtl->stack_realign_processed)
4041 crtl->stack_alignment_estimated = boundary;
4042 else
4043 {
4044 /* If stack is realigned and stack alignment value
4045 hasn't been finalized, it is OK not to increase
4046 stack_alignment_estimated. The bigger alignment
4047 requirement is recorded in stack_alignment_needed
4048 below. */
4049 gcc_assert (!crtl->stack_realign_finalized
4050 && crtl->stack_realign_needed);
4051 }
4052 }
4053 }
4054
4055 if (ARGS_GROW_DOWNWARD)
4056 {
4057 locate->slot_offset.constant = -initial_offset_ptr->constant;
4058 if (initial_offset_ptr->var)
4059 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4060 initial_offset_ptr->var);
4061
4062 {
4063 tree s2 = sizetree;
4064 if (where_pad != PAD_NONE
4065 && (!tree_fits_uhwi_p (sizetree)
4066 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4067 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4068 SUB_PARM_SIZE (locate->slot_offset, s2);
4069 }
4070
4071 locate->slot_offset.constant += part_size_in_regs;
4072
4073 if (!in_regs || reg_parm_stack_space > 0)
4074 pad_to_arg_alignment (&locate->slot_offset, boundary,
4075 &locate->alignment_pad);
4076
4077 locate->size.constant = (-initial_offset_ptr->constant
4078 - locate->slot_offset.constant);
4079 if (initial_offset_ptr->var)
4080 locate->size.var = size_binop (MINUS_EXPR,
4081 size_binop (MINUS_EXPR,
4082 ssize_int (0),
4083 initial_offset_ptr->var),
4084 locate->slot_offset.var);
4085
4086 /* Pad_below needs the pre-rounded size to know how much to pad
4087 below. */
4088 locate->offset = locate->slot_offset;
4089 if (where_pad == PAD_DOWNWARD)
4090 pad_below (&locate->offset, passed_mode, sizetree);
4091
4092 }
4093 else
4094 {
4095 if (!in_regs || reg_parm_stack_space > 0)
4096 pad_to_arg_alignment (initial_offset_ptr, boundary,
4097 &locate->alignment_pad);
4098 locate->slot_offset = *initial_offset_ptr;
4099
4100 #ifdef PUSH_ROUNDING
4101 if (passed_mode != BLKmode)
4102 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4103 #endif
4104
4105 /* Pad_below needs the pre-rounded size to know how much to pad below
4106 so this must be done before rounding up. */
4107 locate->offset = locate->slot_offset;
4108 if (where_pad == PAD_DOWNWARD)
4109 pad_below (&locate->offset, passed_mode, sizetree);
4110
4111 if (where_pad != PAD_NONE
4112 && (!tree_fits_uhwi_p (sizetree)
4113 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4114 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4115
4116 ADD_PARM_SIZE (locate->size, sizetree);
4117
4118 locate->size.constant -= part_size_in_regs;
4119 }
4120
4121 locate->offset.constant
4122 += targetm.calls.function_arg_offset (passed_mode, type);
4123 }
4124
4125 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4126 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4127
4128 static void
4129 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4130 struct args_size *alignment_pad)
4131 {
4132 tree save_var = NULL_TREE;
4133 poly_int64 save_constant = 0;
4134 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4135 poly_int64 sp_offset = STACK_POINTER_OFFSET;
4136
4137 #ifdef SPARC_STACK_BOUNDARY_HACK
4138 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4139 the real alignment of %sp. However, when it does this, the
4140 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4141 if (SPARC_STACK_BOUNDARY_HACK)
4142 sp_offset = 0;
4143 #endif
4144
4145 if (boundary > PARM_BOUNDARY)
4146 {
4147 save_var = offset_ptr->var;
4148 save_constant = offset_ptr->constant;
4149 }
4150
4151 alignment_pad->var = NULL_TREE;
4152 alignment_pad->constant = 0;
4153
4154 if (boundary > BITS_PER_UNIT)
4155 {
4156 int misalign;
4157 if (offset_ptr->var
4158 || !known_misalignment (offset_ptr->constant + sp_offset,
4159 boundary_in_bytes, &misalign))
4160 {
4161 tree sp_offset_tree = ssize_int (sp_offset);
4162 tree offset = size_binop (PLUS_EXPR,
4163 ARGS_SIZE_TREE (*offset_ptr),
4164 sp_offset_tree);
4165 tree rounded;
4166 if (ARGS_GROW_DOWNWARD)
4167 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4168 else
4169 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4170
4171 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4172 /* ARGS_SIZE_TREE includes constant term. */
4173 offset_ptr->constant = 0;
4174 if (boundary > PARM_BOUNDARY)
4175 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4176 save_var);
4177 }
4178 else
4179 {
4180 if (ARGS_GROW_DOWNWARD)
4181 offset_ptr->constant -= misalign;
4182 else
4183 offset_ptr->constant += -misalign & (boundary_in_bytes - 1);
4184
4185 if (boundary > PARM_BOUNDARY)
4186 alignment_pad->constant = offset_ptr->constant - save_constant;
4187 }
4188 }
4189 }
4190
4191 static void
4192 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4193 {
4194 unsigned int align = PARM_BOUNDARY / BITS_PER_UNIT;
4195 int misalign;
4196 if (passed_mode != BLKmode
4197 && known_misalignment (GET_MODE_SIZE (passed_mode), align, &misalign))
4198 offset_ptr->constant += -misalign & (align - 1);
4199 else
4200 {
4201 if (TREE_CODE (sizetree) != INTEGER_CST
4202 || (TREE_INT_CST_LOW (sizetree) & (align - 1)) != 0)
4203 {
4204 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4205 tree s2 = round_up (sizetree, align);
4206 /* Add it in. */
4207 ADD_PARM_SIZE (*offset_ptr, s2);
4208 SUB_PARM_SIZE (*offset_ptr, sizetree);
4209 }
4210 }
4211 }
4212 \f
4213
4214 /* True if register REGNO was alive at a place where `setjmp' was
4215 called and was set more than once or is an argument. Such regs may
4216 be clobbered by `longjmp'. */
4217
4218 static bool
4219 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4220 {
4221 /* There appear to be cases where some local vars never reach the
4222 backend but have bogus regnos. */
4223 if (regno >= max_reg_num ())
4224 return false;
4225
4226 return ((REG_N_SETS (regno) > 1
4227 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4228 regno))
4229 && REGNO_REG_SET_P (setjmp_crosses, regno));
4230 }
4231
4232 /* Walk the tree of blocks describing the binding levels within a
4233 function and warn about variables the might be killed by setjmp or
4234 vfork. This is done after calling flow_analysis before register
4235 allocation since that will clobber the pseudo-regs to hard
4236 regs. */
4237
4238 static void
4239 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4240 {
4241 tree decl, sub;
4242
4243 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4244 {
4245 if (VAR_P (decl)
4246 && DECL_RTL_SET_P (decl)
4247 && REG_P (DECL_RTL (decl))
4248 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4249 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4250 " %<longjmp%> or %<vfork%>", decl);
4251 }
4252
4253 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4254 setjmp_vars_warning (setjmp_crosses, sub);
4255 }
4256
4257 /* Do the appropriate part of setjmp_vars_warning
4258 but for arguments instead of local variables. */
4259
4260 static void
4261 setjmp_args_warning (bitmap setjmp_crosses)
4262 {
4263 tree decl;
4264 for (decl = DECL_ARGUMENTS (current_function_decl);
4265 decl; decl = DECL_CHAIN (decl))
4266 if (DECL_RTL (decl) != 0
4267 && REG_P (DECL_RTL (decl))
4268 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4269 warning (OPT_Wclobbered,
4270 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4271 decl);
4272 }
4273
4274 /* Generate warning messages for variables live across setjmp. */
4275
4276 void
4277 generate_setjmp_warnings (void)
4278 {
4279 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4280
4281 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4282 || bitmap_empty_p (setjmp_crosses))
4283 return;
4284
4285 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4286 setjmp_args_warning (setjmp_crosses);
4287 }
4288
4289 \f
4290 /* Reverse the order of elements in the fragment chain T of blocks,
4291 and return the new head of the chain (old last element).
4292 In addition to that clear BLOCK_SAME_RANGE flags when needed
4293 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4294 its super fragment origin. */
4295
4296 static tree
4297 block_fragments_nreverse (tree t)
4298 {
4299 tree prev = 0, block, next, prev_super = 0;
4300 tree super = BLOCK_SUPERCONTEXT (t);
4301 if (BLOCK_FRAGMENT_ORIGIN (super))
4302 super = BLOCK_FRAGMENT_ORIGIN (super);
4303 for (block = t; block; block = next)
4304 {
4305 next = BLOCK_FRAGMENT_CHAIN (block);
4306 BLOCK_FRAGMENT_CHAIN (block) = prev;
4307 if ((prev && !BLOCK_SAME_RANGE (prev))
4308 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4309 != prev_super))
4310 BLOCK_SAME_RANGE (block) = 0;
4311 prev_super = BLOCK_SUPERCONTEXT (block);
4312 BLOCK_SUPERCONTEXT (block) = super;
4313 prev = block;
4314 }
4315 t = BLOCK_FRAGMENT_ORIGIN (t);
4316 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4317 != prev_super)
4318 BLOCK_SAME_RANGE (t) = 0;
4319 BLOCK_SUPERCONTEXT (t) = super;
4320 return prev;
4321 }
4322
4323 /* Reverse the order of elements in the chain T of blocks,
4324 and return the new head of the chain (old last element).
4325 Also do the same on subblocks and reverse the order of elements
4326 in BLOCK_FRAGMENT_CHAIN as well. */
4327
4328 static tree
4329 blocks_nreverse_all (tree t)
4330 {
4331 tree prev = 0, block, next;
4332 for (block = t; block; block = next)
4333 {
4334 next = BLOCK_CHAIN (block);
4335 BLOCK_CHAIN (block) = prev;
4336 if (BLOCK_FRAGMENT_CHAIN (block)
4337 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4338 {
4339 BLOCK_FRAGMENT_CHAIN (block)
4340 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4341 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4342 BLOCK_SAME_RANGE (block) = 0;
4343 }
4344 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4345 prev = block;
4346 }
4347 return prev;
4348 }
4349
4350
4351 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4352 and create duplicate blocks. */
4353 /* ??? Need an option to either create block fragments or to create
4354 abstract origin duplicates of a source block. It really depends
4355 on what optimization has been performed. */
4356
4357 void
4358 reorder_blocks (void)
4359 {
4360 tree block = DECL_INITIAL (current_function_decl);
4361
4362 if (block == NULL_TREE)
4363 return;
4364
4365 auto_vec<tree, 10> block_stack;
4366
4367 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4368 clear_block_marks (block);
4369
4370 /* Prune the old trees away, so that they don't get in the way. */
4371 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4372 BLOCK_CHAIN (block) = NULL_TREE;
4373
4374 /* Recreate the block tree from the note nesting. */
4375 reorder_blocks_1 (get_insns (), block, &block_stack);
4376 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4377 }
4378
4379 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4380
4381 void
4382 clear_block_marks (tree block)
4383 {
4384 while (block)
4385 {
4386 TREE_ASM_WRITTEN (block) = 0;
4387 clear_block_marks (BLOCK_SUBBLOCKS (block));
4388 block = BLOCK_CHAIN (block);
4389 }
4390 }
4391
4392 static void
4393 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4394 vec<tree> *p_block_stack)
4395 {
4396 rtx_insn *insn;
4397 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4398
4399 for (insn = insns; insn; insn = NEXT_INSN (insn))
4400 {
4401 if (NOTE_P (insn))
4402 {
4403 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4404 {
4405 tree block = NOTE_BLOCK (insn);
4406 tree origin;
4407
4408 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4409 origin = block;
4410
4411 if (prev_end)
4412 BLOCK_SAME_RANGE (prev_end) = 0;
4413 prev_end = NULL_TREE;
4414
4415 /* If we have seen this block before, that means it now
4416 spans multiple address regions. Create a new fragment. */
4417 if (TREE_ASM_WRITTEN (block))
4418 {
4419 tree new_block = copy_node (block);
4420
4421 BLOCK_SAME_RANGE (new_block) = 0;
4422 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4423 BLOCK_FRAGMENT_CHAIN (new_block)
4424 = BLOCK_FRAGMENT_CHAIN (origin);
4425 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4426
4427 NOTE_BLOCK (insn) = new_block;
4428 block = new_block;
4429 }
4430
4431 if (prev_beg == current_block && prev_beg)
4432 BLOCK_SAME_RANGE (block) = 1;
4433
4434 prev_beg = origin;
4435
4436 BLOCK_SUBBLOCKS (block) = 0;
4437 TREE_ASM_WRITTEN (block) = 1;
4438 /* When there's only one block for the entire function,
4439 current_block == block and we mustn't do this, it
4440 will cause infinite recursion. */
4441 if (block != current_block)
4442 {
4443 tree super;
4444 if (block != origin)
4445 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4446 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4447 (origin))
4448 == current_block);
4449 if (p_block_stack->is_empty ())
4450 super = current_block;
4451 else
4452 {
4453 super = p_block_stack->last ();
4454 gcc_assert (super == current_block
4455 || BLOCK_FRAGMENT_ORIGIN (super)
4456 == current_block);
4457 }
4458 BLOCK_SUPERCONTEXT (block) = super;
4459 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4460 BLOCK_SUBBLOCKS (current_block) = block;
4461 current_block = origin;
4462 }
4463 p_block_stack->safe_push (block);
4464 }
4465 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4466 {
4467 NOTE_BLOCK (insn) = p_block_stack->pop ();
4468 current_block = BLOCK_SUPERCONTEXT (current_block);
4469 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4470 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4471 prev_beg = NULL_TREE;
4472 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4473 ? NOTE_BLOCK (insn) : NULL_TREE;
4474 }
4475 }
4476 else
4477 {
4478 prev_beg = NULL_TREE;
4479 if (prev_end)
4480 BLOCK_SAME_RANGE (prev_end) = 0;
4481 prev_end = NULL_TREE;
4482 }
4483 }
4484 }
4485
4486 /* Reverse the order of elements in the chain T of blocks,
4487 and return the new head of the chain (old last element). */
4488
4489 tree
4490 blocks_nreverse (tree t)
4491 {
4492 tree prev = 0, block, next;
4493 for (block = t; block; block = next)
4494 {
4495 next = BLOCK_CHAIN (block);
4496 BLOCK_CHAIN (block) = prev;
4497 prev = block;
4498 }
4499 return prev;
4500 }
4501
4502 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4503 by modifying the last node in chain 1 to point to chain 2. */
4504
4505 tree
4506 block_chainon (tree op1, tree op2)
4507 {
4508 tree t1;
4509
4510 if (!op1)
4511 return op2;
4512 if (!op2)
4513 return op1;
4514
4515 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4516 continue;
4517 BLOCK_CHAIN (t1) = op2;
4518
4519 #ifdef ENABLE_TREE_CHECKING
4520 {
4521 tree t2;
4522 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4523 gcc_assert (t2 != t1);
4524 }
4525 #endif
4526
4527 return op1;
4528 }
4529
4530 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4531 non-NULL, list them all into VECTOR, in a depth-first preorder
4532 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4533 blocks. */
4534
4535 static int
4536 all_blocks (tree block, tree *vector)
4537 {
4538 int n_blocks = 0;
4539
4540 while (block)
4541 {
4542 TREE_ASM_WRITTEN (block) = 0;
4543
4544 /* Record this block. */
4545 if (vector)
4546 vector[n_blocks] = block;
4547
4548 ++n_blocks;
4549
4550 /* Record the subblocks, and their subblocks... */
4551 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4552 vector ? vector + n_blocks : 0);
4553 block = BLOCK_CHAIN (block);
4554 }
4555
4556 return n_blocks;
4557 }
4558
4559 /* Return a vector containing all the blocks rooted at BLOCK. The
4560 number of elements in the vector is stored in N_BLOCKS_P. The
4561 vector is dynamically allocated; it is the caller's responsibility
4562 to call `free' on the pointer returned. */
4563
4564 static tree *
4565 get_block_vector (tree block, int *n_blocks_p)
4566 {
4567 tree *block_vector;
4568
4569 *n_blocks_p = all_blocks (block, NULL);
4570 block_vector = XNEWVEC (tree, *n_blocks_p);
4571 all_blocks (block, block_vector);
4572
4573 return block_vector;
4574 }
4575
4576 static GTY(()) int next_block_index = 2;
4577
4578 /* Set BLOCK_NUMBER for all the blocks in FN. */
4579
4580 void
4581 number_blocks (tree fn)
4582 {
4583 int i;
4584 int n_blocks;
4585 tree *block_vector;
4586
4587 /* For XCOFF debugging output, we start numbering the blocks
4588 from 1 within each function, rather than keeping a running
4589 count. */
4590 #if defined (XCOFF_DEBUGGING_INFO)
4591 if (write_symbols == XCOFF_DEBUG)
4592 next_block_index = 1;
4593 #endif
4594
4595 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4596
4597 /* The top-level BLOCK isn't numbered at all. */
4598 for (i = 1; i < n_blocks; ++i)
4599 /* We number the blocks from two. */
4600 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4601
4602 free (block_vector);
4603
4604 return;
4605 }
4606
4607 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4608
4609 DEBUG_FUNCTION tree
4610 debug_find_var_in_block_tree (tree var, tree block)
4611 {
4612 tree t;
4613
4614 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4615 if (t == var)
4616 return block;
4617
4618 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4619 {
4620 tree ret = debug_find_var_in_block_tree (var, t);
4621 if (ret)
4622 return ret;
4623 }
4624
4625 return NULL_TREE;
4626 }
4627 \f
4628 /* Keep track of whether we're in a dummy function context. If we are,
4629 we don't want to invoke the set_current_function hook, because we'll
4630 get into trouble if the hook calls target_reinit () recursively or
4631 when the initial initialization is not yet complete. */
4632
4633 static bool in_dummy_function;
4634
4635 /* Invoke the target hook when setting cfun. Update the optimization options
4636 if the function uses different options than the default. */
4637
4638 static void
4639 invoke_set_current_function_hook (tree fndecl)
4640 {
4641 if (!in_dummy_function)
4642 {
4643 tree opts = ((fndecl)
4644 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4645 : optimization_default_node);
4646
4647 if (!opts)
4648 opts = optimization_default_node;
4649
4650 /* Change optimization options if needed. */
4651 if (optimization_current_node != opts)
4652 {
4653 optimization_current_node = opts;
4654 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4655 }
4656
4657 targetm.set_current_function (fndecl);
4658 this_fn_optabs = this_target_optabs;
4659
4660 /* Initialize global alignment variables after op. */
4661 parse_alignment_opts ();
4662
4663 if (opts != optimization_default_node)
4664 {
4665 init_tree_optimization_optabs (opts);
4666 if (TREE_OPTIMIZATION_OPTABS (opts))
4667 this_fn_optabs = (struct target_optabs *)
4668 TREE_OPTIMIZATION_OPTABS (opts);
4669 }
4670 }
4671 }
4672
4673 /* cfun should never be set directly; use this function. */
4674
4675 void
4676 set_cfun (struct function *new_cfun, bool force)
4677 {
4678 if (cfun != new_cfun || force)
4679 {
4680 cfun = new_cfun;
4681 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4682 redirect_edge_var_map_empty ();
4683 }
4684 }
4685
4686 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4687
4688 static vec<function *> cfun_stack;
4689
4690 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4691 current_function_decl accordingly. */
4692
4693 void
4694 push_cfun (struct function *new_cfun)
4695 {
4696 gcc_assert ((!cfun && !current_function_decl)
4697 || (cfun && current_function_decl == cfun->decl));
4698 cfun_stack.safe_push (cfun);
4699 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4700 set_cfun (new_cfun);
4701 }
4702
4703 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4704
4705 void
4706 pop_cfun (void)
4707 {
4708 struct function *new_cfun = cfun_stack.pop ();
4709 /* When in_dummy_function, we do have a cfun but current_function_decl is
4710 NULL. We also allow pushing NULL cfun and subsequently changing
4711 current_function_decl to something else and have both restored by
4712 pop_cfun. */
4713 gcc_checking_assert (in_dummy_function
4714 || !cfun
4715 || current_function_decl == cfun->decl);
4716 set_cfun (new_cfun);
4717 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4718 }
4719
4720 /* Return value of funcdef and increase it. */
4721 int
4722 get_next_funcdef_no (void)
4723 {
4724 return funcdef_no++;
4725 }
4726
4727 /* Return value of funcdef. */
4728 int
4729 get_last_funcdef_no (void)
4730 {
4731 return funcdef_no;
4732 }
4733
4734 /* Allocate a function structure for FNDECL and set its contents
4735 to the defaults. Set cfun to the newly-allocated object.
4736 Some of the helper functions invoked during initialization assume
4737 that cfun has already been set. Therefore, assign the new object
4738 directly into cfun and invoke the back end hook explicitly at the
4739 very end, rather than initializing a temporary and calling set_cfun
4740 on it.
4741
4742 ABSTRACT_P is true if this is a function that will never be seen by
4743 the middle-end. Such functions are front-end concepts (like C++
4744 function templates) that do not correspond directly to functions
4745 placed in object files. */
4746
4747 void
4748 allocate_struct_function (tree fndecl, bool abstract_p)
4749 {
4750 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4751
4752 cfun = ggc_cleared_alloc<function> ();
4753
4754 init_eh_for_function ();
4755
4756 if (init_machine_status)
4757 cfun->machine = (*init_machine_status) ();
4758
4759 #ifdef OVERRIDE_ABI_FORMAT
4760 OVERRIDE_ABI_FORMAT (fndecl);
4761 #endif
4762
4763 if (fndecl != NULL_TREE)
4764 {
4765 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4766 cfun->decl = fndecl;
4767 current_function_funcdef_no = get_next_funcdef_no ();
4768 }
4769
4770 invoke_set_current_function_hook (fndecl);
4771
4772 if (fndecl != NULL_TREE)
4773 {
4774 tree result = DECL_RESULT (fndecl);
4775
4776 if (!abstract_p)
4777 {
4778 /* Now that we have activated any function-specific attributes
4779 that might affect layout, particularly vector modes, relayout
4780 each of the parameters and the result. */
4781 relayout_decl (result);
4782 for (tree parm = DECL_ARGUMENTS (fndecl); parm;
4783 parm = DECL_CHAIN (parm))
4784 relayout_decl (parm);
4785
4786 /* Similarly relayout the function decl. */
4787 targetm.target_option.relayout_function (fndecl);
4788 }
4789
4790 if (!abstract_p && aggregate_value_p (result, fndecl))
4791 {
4792 #ifdef PCC_STATIC_STRUCT_RETURN
4793 cfun->returns_pcc_struct = 1;
4794 #endif
4795 cfun->returns_struct = 1;
4796 }
4797
4798 cfun->stdarg = stdarg_p (fntype);
4799
4800 /* Assume all registers in stdarg functions need to be saved. */
4801 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4802 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4803
4804 /* ??? This could be set on a per-function basis by the front-end
4805 but is this worth the hassle? */
4806 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4807 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4808
4809 if (!profile_flag && !flag_instrument_function_entry_exit)
4810 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4811 }
4812
4813 /* Don't enable begin stmt markers if var-tracking at assignments is
4814 disabled. The markers make little sense without the variable
4815 binding annotations among them. */
4816 cfun->debug_nonbind_markers = lang_hooks.emits_begin_stmt
4817 && MAY_HAVE_DEBUG_MARKER_STMTS;
4818 }
4819
4820 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4821 instead of just setting it. */
4822
4823 void
4824 push_struct_function (tree fndecl)
4825 {
4826 /* When in_dummy_function we might be in the middle of a pop_cfun and
4827 current_function_decl and cfun may not match. */
4828 gcc_assert (in_dummy_function
4829 || (!cfun && !current_function_decl)
4830 || (cfun && current_function_decl == cfun->decl));
4831 cfun_stack.safe_push (cfun);
4832 current_function_decl = fndecl;
4833 allocate_struct_function (fndecl, false);
4834 }
4835
4836 /* Reset crtl and other non-struct-function variables to defaults as
4837 appropriate for emitting rtl at the start of a function. */
4838
4839 static void
4840 prepare_function_start (void)
4841 {
4842 gcc_assert (!get_last_insn ());
4843 init_temp_slots ();
4844 init_emit ();
4845 init_varasm_status ();
4846 init_expr ();
4847 default_rtl_profile ();
4848
4849 if (flag_stack_usage_info)
4850 {
4851 cfun->su = ggc_cleared_alloc<stack_usage> ();
4852 cfun->su->static_stack_size = -1;
4853 }
4854
4855 cse_not_expected = ! optimize;
4856
4857 /* Caller save not needed yet. */
4858 caller_save_needed = 0;
4859
4860 /* We haven't done register allocation yet. */
4861 reg_renumber = 0;
4862
4863 /* Indicate that we have not instantiated virtual registers yet. */
4864 virtuals_instantiated = 0;
4865
4866 /* Indicate that we want CONCATs now. */
4867 generating_concat_p = 1;
4868
4869 /* Indicate we have no need of a frame pointer yet. */
4870 frame_pointer_needed = 0;
4871 }
4872
4873 void
4874 push_dummy_function (bool with_decl)
4875 {
4876 tree fn_decl, fn_type, fn_result_decl;
4877
4878 gcc_assert (!in_dummy_function);
4879 in_dummy_function = true;
4880
4881 if (with_decl)
4882 {
4883 fn_type = build_function_type_list (void_type_node, NULL_TREE);
4884 fn_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
4885 fn_type);
4886 fn_result_decl = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
4887 NULL_TREE, void_type_node);
4888 DECL_RESULT (fn_decl) = fn_result_decl;
4889 }
4890 else
4891 fn_decl = NULL_TREE;
4892
4893 push_struct_function (fn_decl);
4894 }
4895
4896 /* Initialize the rtl expansion mechanism so that we can do simple things
4897 like generate sequences. This is used to provide a context during global
4898 initialization of some passes. You must call expand_dummy_function_end
4899 to exit this context. */
4900
4901 void
4902 init_dummy_function_start (void)
4903 {
4904 push_dummy_function (false);
4905 prepare_function_start ();
4906 }
4907
4908 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4909 and initialize static variables for generating RTL for the statements
4910 of the function. */
4911
4912 void
4913 init_function_start (tree subr)
4914 {
4915 /* Initialize backend, if needed. */
4916 initialize_rtl ();
4917
4918 prepare_function_start ();
4919 decide_function_section (subr);
4920
4921 /* Warn if this value is an aggregate type,
4922 regardless of which calling convention we are using for it. */
4923 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4924 warning (OPT_Waggregate_return, "function returns an aggregate");
4925 }
4926
4927 /* Expand code to verify the stack_protect_guard. This is invoked at
4928 the end of a function to be protected. */
4929
4930 void
4931 stack_protect_epilogue (void)
4932 {
4933 tree guard_decl = crtl->stack_protect_guard_decl;
4934 rtx_code_label *label = gen_label_rtx ();
4935 rtx x, y;
4936 rtx_insn *seq = NULL;
4937
4938 x = expand_normal (crtl->stack_protect_guard);
4939
4940 if (targetm.have_stack_protect_combined_test () && guard_decl)
4941 {
4942 gcc_assert (DECL_P (guard_decl));
4943 y = DECL_RTL (guard_decl);
4944 /* Allow the target to compute address of Y and compare it with X without
4945 leaking Y into a register. This combined address + compare pattern
4946 allows the target to prevent spilling of any intermediate results by
4947 splitting it after register allocator. */
4948 seq = targetm.gen_stack_protect_combined_test (x, y, label);
4949 }
4950 else
4951 {
4952 if (guard_decl)
4953 y = expand_normal (guard_decl);
4954 else
4955 y = const0_rtx;
4956
4957 /* Allow the target to compare Y with X without leaking either into
4958 a register. */
4959 if (targetm.have_stack_protect_test ())
4960 seq = targetm.gen_stack_protect_test (x, y, label);
4961 }
4962
4963 if (seq)
4964 emit_insn (seq);
4965 else
4966 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4967
4968 /* The noreturn predictor has been moved to the tree level. The rtl-level
4969 predictors estimate this branch about 20%, which isn't enough to get
4970 things moved out of line. Since this is the only extant case of adding
4971 a noreturn function at the rtl level, it doesn't seem worth doing ought
4972 except adding the prediction by hand. */
4973 rtx_insn *tmp = get_last_insn ();
4974 if (JUMP_P (tmp))
4975 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4976
4977 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
4978 free_temp_slots ();
4979 emit_label (label);
4980 }
4981 \f
4982 /* Start the RTL for a new function, and set variables used for
4983 emitting RTL.
4984 SUBR is the FUNCTION_DECL node.
4985 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4986 the function's parameters, which must be run at any return statement. */
4987
4988 void
4989 expand_function_start (tree subr)
4990 {
4991 /* Make sure volatile mem refs aren't considered
4992 valid operands of arithmetic insns. */
4993 init_recog_no_volatile ();
4994
4995 crtl->profile
4996 = (profile_flag
4997 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4998
4999 crtl->limit_stack
5000 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
5001
5002 /* Make the label for return statements to jump to. Do not special
5003 case machines with special return instructions -- they will be
5004 handled later during jump, ifcvt, or epilogue creation. */
5005 return_label = gen_label_rtx ();
5006
5007 /* Initialize rtx used to return the value. */
5008 /* Do this before assign_parms so that we copy the struct value address
5009 before any library calls that assign parms might generate. */
5010
5011 /* Decide whether to return the value in memory or in a register. */
5012 tree res = DECL_RESULT (subr);
5013 if (aggregate_value_p (res, subr))
5014 {
5015 /* Returning something that won't go in a register. */
5016 rtx value_address = 0;
5017
5018 #ifdef PCC_STATIC_STRUCT_RETURN
5019 if (cfun->returns_pcc_struct)
5020 {
5021 int size = int_size_in_bytes (TREE_TYPE (res));
5022 value_address = assemble_static_space (size);
5023 }
5024 else
5025 #endif
5026 {
5027 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
5028 /* Expect to be passed the address of a place to store the value.
5029 If it is passed as an argument, assign_parms will take care of
5030 it. */
5031 if (sv)
5032 {
5033 value_address = gen_reg_rtx (Pmode);
5034 emit_move_insn (value_address, sv);
5035 }
5036 }
5037 if (value_address)
5038 {
5039 rtx x = value_address;
5040 if (!DECL_BY_REFERENCE (res))
5041 {
5042 x = gen_rtx_MEM (DECL_MODE (res), x);
5043 set_mem_attributes (x, res, 1);
5044 }
5045 set_parm_rtl (res, x);
5046 }
5047 }
5048 else if (DECL_MODE (res) == VOIDmode)
5049 /* If return mode is void, this decl rtl should not be used. */
5050 set_parm_rtl (res, NULL_RTX);
5051 else
5052 {
5053 /* Compute the return values into a pseudo reg, which we will copy
5054 into the true return register after the cleanups are done. */
5055 tree return_type = TREE_TYPE (res);
5056
5057 /* If we may coalesce this result, make sure it has the expected mode
5058 in case it was promoted. But we need not bother about BLKmode. */
5059 machine_mode promoted_mode
5060 = flag_tree_coalesce_vars && is_gimple_reg (res)
5061 ? promote_ssa_mode (ssa_default_def (cfun, res), NULL)
5062 : BLKmode;
5063
5064 if (promoted_mode != BLKmode)
5065 set_parm_rtl (res, gen_reg_rtx (promoted_mode));
5066 else if (TYPE_MODE (return_type) != BLKmode
5067 && targetm.calls.return_in_msb (return_type))
5068 /* expand_function_end will insert the appropriate padding in
5069 this case. Use the return value's natural (unpadded) mode
5070 within the function proper. */
5071 set_parm_rtl (res, gen_reg_rtx (TYPE_MODE (return_type)));
5072 else
5073 {
5074 /* In order to figure out what mode to use for the pseudo, we
5075 figure out what the mode of the eventual return register will
5076 actually be, and use that. */
5077 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
5078
5079 /* Structures that are returned in registers are not
5080 aggregate_value_p, so we may see a PARALLEL or a REG. */
5081 if (REG_P (hard_reg))
5082 set_parm_rtl (res, gen_reg_rtx (GET_MODE (hard_reg)));
5083 else
5084 {
5085 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5086 set_parm_rtl (res, gen_group_rtx (hard_reg));
5087 }
5088 }
5089
5090 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5091 result to the real return register(s). */
5092 DECL_REGISTER (res) = 1;
5093 }
5094
5095 /* Initialize rtx for parameters and local variables.
5096 In some cases this requires emitting insns. */
5097 assign_parms (subr);
5098
5099 /* If function gets a static chain arg, store it. */
5100 if (cfun->static_chain_decl)
5101 {
5102 tree parm = cfun->static_chain_decl;
5103 rtx local, chain;
5104 rtx_insn *insn;
5105 int unsignedp;
5106
5107 local = gen_reg_rtx (promote_decl_mode (parm, &unsignedp));
5108 chain = targetm.calls.static_chain (current_function_decl, true);
5109
5110 set_decl_incoming_rtl (parm, chain, false);
5111 set_parm_rtl (parm, local);
5112 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5113
5114 if (GET_MODE (local) != GET_MODE (chain))
5115 {
5116 convert_move (local, chain, unsignedp);
5117 insn = get_last_insn ();
5118 }
5119 else
5120 insn = emit_move_insn (local, chain);
5121
5122 /* Mark the register as eliminable, similar to parameters. */
5123 if (MEM_P (chain)
5124 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
5125 set_dst_reg_note (insn, REG_EQUIV, chain, local);
5126
5127 /* If we aren't optimizing, save the static chain onto the stack. */
5128 if (!optimize)
5129 {
5130 tree saved_static_chain_decl
5131 = build_decl (DECL_SOURCE_LOCATION (parm), VAR_DECL,
5132 DECL_NAME (parm), TREE_TYPE (parm));
5133 rtx saved_static_chain_rtx
5134 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5135 SET_DECL_RTL (saved_static_chain_decl, saved_static_chain_rtx);
5136 emit_move_insn (saved_static_chain_rtx, chain);
5137 SET_DECL_VALUE_EXPR (parm, saved_static_chain_decl);
5138 DECL_HAS_VALUE_EXPR_P (parm) = 1;
5139 }
5140 }
5141
5142 /* The following was moved from init_function_start.
5143 The move was supposed to make sdb output more accurate. */
5144 /* Indicate the beginning of the function body,
5145 as opposed to parm setup. */
5146 emit_note (NOTE_INSN_FUNCTION_BEG);
5147
5148 gcc_assert (NOTE_P (get_last_insn ()));
5149
5150 parm_birth_insn = get_last_insn ();
5151
5152 /* If the function receives a non-local goto, then store the
5153 bits we need to restore the frame pointer. */
5154 if (cfun->nonlocal_goto_save_area)
5155 {
5156 tree t_save;
5157 rtx r_save;
5158
5159 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5160 gcc_assert (DECL_RTL_SET_P (var));
5161
5162 t_save = build4 (ARRAY_REF,
5163 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
5164 cfun->nonlocal_goto_save_area,
5165 integer_zero_node, NULL_TREE, NULL_TREE);
5166 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
5167 gcc_assert (GET_MODE (r_save) == Pmode);
5168
5169 emit_move_insn (r_save, hard_frame_pointer_rtx);
5170 update_nonlocal_goto_save_area ();
5171 }
5172
5173 if (crtl->profile)
5174 {
5175 #ifdef PROFILE_HOOK
5176 PROFILE_HOOK (current_function_funcdef_no);
5177 #endif
5178 }
5179
5180 /* If we are doing generic stack checking, the probe should go here. */
5181 if (flag_stack_check == GENERIC_STACK_CHECK)
5182 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
5183 }
5184 \f
5185 void
5186 pop_dummy_function (void)
5187 {
5188 pop_cfun ();
5189 in_dummy_function = false;
5190 }
5191
5192 /* Undo the effects of init_dummy_function_start. */
5193 void
5194 expand_dummy_function_end (void)
5195 {
5196 gcc_assert (in_dummy_function);
5197
5198 /* End any sequences that failed to be closed due to syntax errors. */
5199 while (in_sequence_p ())
5200 end_sequence ();
5201
5202 /* Outside function body, can't compute type's actual size
5203 until next function's body starts. */
5204
5205 free_after_parsing (cfun);
5206 free_after_compilation (cfun);
5207 pop_dummy_function ();
5208 }
5209
5210 /* Helper for diddle_return_value. */
5211
5212 void
5213 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5214 {
5215 if (! outgoing)
5216 return;
5217
5218 if (REG_P (outgoing))
5219 (*doit) (outgoing, arg);
5220 else if (GET_CODE (outgoing) == PARALLEL)
5221 {
5222 int i;
5223
5224 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5225 {
5226 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5227
5228 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5229 (*doit) (x, arg);
5230 }
5231 }
5232 }
5233
5234 /* Call DOIT for each hard register used as a return value from
5235 the current function. */
5236
5237 void
5238 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5239 {
5240 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5241 }
5242
5243 static void
5244 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5245 {
5246 emit_clobber (reg);
5247 }
5248
5249 void
5250 clobber_return_register (void)
5251 {
5252 diddle_return_value (do_clobber_return_reg, NULL);
5253
5254 /* In case we do use pseudo to return value, clobber it too. */
5255 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5256 {
5257 tree decl_result = DECL_RESULT (current_function_decl);
5258 rtx decl_rtl = DECL_RTL (decl_result);
5259 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
5260 {
5261 do_clobber_return_reg (decl_rtl, NULL);
5262 }
5263 }
5264 }
5265
5266 static void
5267 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5268 {
5269 emit_use (reg);
5270 }
5271
5272 static void
5273 use_return_register (void)
5274 {
5275 diddle_return_value (do_use_return_reg, NULL);
5276 }
5277
5278 /* Generate RTL for the end of the current function. */
5279
5280 void
5281 expand_function_end (void)
5282 {
5283 /* If arg_pointer_save_area was referenced only from a nested
5284 function, we will not have initialized it yet. Do that now. */
5285 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
5286 get_arg_pointer_save_area ();
5287
5288 /* If we are doing generic stack checking and this function makes calls,
5289 do a stack probe at the start of the function to ensure we have enough
5290 space for another stack frame. */
5291 if (flag_stack_check == GENERIC_STACK_CHECK)
5292 {
5293 rtx_insn *insn, *seq;
5294
5295 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5296 if (CALL_P (insn))
5297 {
5298 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
5299 start_sequence ();
5300 if (STACK_CHECK_MOVING_SP)
5301 anti_adjust_stack_and_probe (max_frame_size, true);
5302 else
5303 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
5304 seq = get_insns ();
5305 end_sequence ();
5306 set_insn_locations (seq, prologue_location);
5307 emit_insn_before (seq, stack_check_probe_note);
5308 break;
5309 }
5310 }
5311
5312 /* End any sequences that failed to be closed due to syntax errors. */
5313 while (in_sequence_p ())
5314 end_sequence ();
5315
5316 clear_pending_stack_adjust ();
5317 do_pending_stack_adjust ();
5318
5319 /* Output a linenumber for the end of the function.
5320 SDB depended on this. */
5321 set_curr_insn_location (input_location);
5322
5323 /* Before the return label (if any), clobber the return
5324 registers so that they are not propagated live to the rest of
5325 the function. This can only happen with functions that drop
5326 through; if there had been a return statement, there would
5327 have either been a return rtx, or a jump to the return label.
5328
5329 We delay actual code generation after the current_function_value_rtx
5330 is computed. */
5331 rtx_insn *clobber_after = get_last_insn ();
5332
5333 /* Output the label for the actual return from the function. */
5334 emit_label (return_label);
5335
5336 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
5337 {
5338 /* Let except.c know where it should emit the call to unregister
5339 the function context for sjlj exceptions. */
5340 if (flag_exceptions)
5341 sjlj_emit_function_exit_after (get_last_insn ());
5342 }
5343
5344 /* If this is an implementation of throw, do what's necessary to
5345 communicate between __builtin_eh_return and the epilogue. */
5346 expand_eh_return ();
5347
5348 /* If stack protection is enabled for this function, check the guard. */
5349 if (crtl->stack_protect_guard
5350 && targetm.stack_protect_runtime_enabled_p ()
5351 && naked_return_label == NULL_RTX)
5352 stack_protect_epilogue ();
5353
5354 /* If scalar return value was computed in a pseudo-reg, or was a named
5355 return value that got dumped to the stack, copy that to the hard
5356 return register. */
5357 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5358 {
5359 tree decl_result = DECL_RESULT (current_function_decl);
5360 rtx decl_rtl = DECL_RTL (decl_result);
5361
5362 if (REG_P (decl_rtl)
5363 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5364 : DECL_REGISTER (decl_result))
5365 {
5366 rtx real_decl_rtl = crtl->return_rtx;
5367 complex_mode cmode;
5368
5369 /* This should be set in assign_parms. */
5370 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5371
5372 /* If this is a BLKmode structure being returned in registers,
5373 then use the mode computed in expand_return. Note that if
5374 decl_rtl is memory, then its mode may have been changed,
5375 but that crtl->return_rtx has not. */
5376 if (GET_MODE (real_decl_rtl) == BLKmode)
5377 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5378
5379 /* If a non-BLKmode return value should be padded at the least
5380 significant end of the register, shift it left by the appropriate
5381 amount. BLKmode results are handled using the group load/store
5382 machinery. */
5383 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5384 && REG_P (real_decl_rtl)
5385 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5386 {
5387 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5388 REGNO (real_decl_rtl)),
5389 decl_rtl);
5390 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5391 }
5392 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5393 {
5394 /* If expand_function_start has created a PARALLEL for decl_rtl,
5395 move the result to the real return registers. Otherwise, do
5396 a group load from decl_rtl for a named return. */
5397 if (GET_CODE (decl_rtl) == PARALLEL)
5398 emit_group_move (real_decl_rtl, decl_rtl);
5399 else
5400 emit_group_load (real_decl_rtl, decl_rtl,
5401 TREE_TYPE (decl_result),
5402 int_size_in_bytes (TREE_TYPE (decl_result)));
5403 }
5404 /* In the case of complex integer modes smaller than a word, we'll
5405 need to generate some non-trivial bitfield insertions. Do that
5406 on a pseudo and not the hard register. */
5407 else if (GET_CODE (decl_rtl) == CONCAT
5408 && is_complex_int_mode (GET_MODE (decl_rtl), &cmode)
5409 && GET_MODE_BITSIZE (cmode) <= BITS_PER_WORD)
5410 {
5411 int old_generating_concat_p;
5412 rtx tmp;
5413
5414 old_generating_concat_p = generating_concat_p;
5415 generating_concat_p = 0;
5416 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5417 generating_concat_p = old_generating_concat_p;
5418
5419 emit_move_insn (tmp, decl_rtl);
5420 emit_move_insn (real_decl_rtl, tmp);
5421 }
5422 /* If a named return value dumped decl_return to memory, then
5423 we may need to re-do the PROMOTE_MODE signed/unsigned
5424 extension. */
5425 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5426 {
5427 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5428 promote_function_mode (TREE_TYPE (decl_result),
5429 GET_MODE (decl_rtl), &unsignedp,
5430 TREE_TYPE (current_function_decl), 1);
5431
5432 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5433 }
5434 else
5435 emit_move_insn (real_decl_rtl, decl_rtl);
5436 }
5437 }
5438
5439 /* If returning a structure, arrange to return the address of the value
5440 in a place where debuggers expect to find it.
5441
5442 If returning a structure PCC style,
5443 the caller also depends on this value.
5444 And cfun->returns_pcc_struct is not necessarily set. */
5445 if ((cfun->returns_struct || cfun->returns_pcc_struct)
5446 && !targetm.calls.omit_struct_return_reg)
5447 {
5448 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5449 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5450 rtx outgoing;
5451
5452 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5453 type = TREE_TYPE (type);
5454 else
5455 value_address = XEXP (value_address, 0);
5456
5457 outgoing = targetm.calls.function_value (build_pointer_type (type),
5458 current_function_decl, true);
5459
5460 /* Mark this as a function return value so integrate will delete the
5461 assignment and USE below when inlining this function. */
5462 REG_FUNCTION_VALUE_P (outgoing) = 1;
5463
5464 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5465 scalar_int_mode mode = as_a <scalar_int_mode> (GET_MODE (outgoing));
5466 value_address = convert_memory_address (mode, value_address);
5467
5468 emit_move_insn (outgoing, value_address);
5469
5470 /* Show return register used to hold result (in this case the address
5471 of the result. */
5472 crtl->return_rtx = outgoing;
5473 }
5474
5475 /* Emit the actual code to clobber return register. Don't emit
5476 it if clobber_after is a barrier, then the previous basic block
5477 certainly doesn't fall thru into the exit block. */
5478 if (!BARRIER_P (clobber_after))
5479 {
5480 start_sequence ();
5481 clobber_return_register ();
5482 rtx_insn *seq = get_insns ();
5483 end_sequence ();
5484
5485 emit_insn_after (seq, clobber_after);
5486 }
5487
5488 /* Output the label for the naked return from the function. */
5489 if (naked_return_label)
5490 emit_label (naked_return_label);
5491
5492 /* @@@ This is a kludge. We want to ensure that instructions that
5493 may trap are not moved into the epilogue by scheduling, because
5494 we don't always emit unwind information for the epilogue. */
5495 if (cfun->can_throw_non_call_exceptions
5496 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5497 emit_insn (gen_blockage ());
5498
5499 /* If stack protection is enabled for this function, check the guard. */
5500 if (crtl->stack_protect_guard
5501 && targetm.stack_protect_runtime_enabled_p ()
5502 && naked_return_label)
5503 stack_protect_epilogue ();
5504
5505 /* If we had calls to alloca, and this machine needs
5506 an accurate stack pointer to exit the function,
5507 insert some code to save and restore the stack pointer. */
5508 if (! EXIT_IGNORE_STACK
5509 && cfun->calls_alloca)
5510 {
5511 rtx tem = 0;
5512
5513 start_sequence ();
5514 emit_stack_save (SAVE_FUNCTION, &tem);
5515 rtx_insn *seq = get_insns ();
5516 end_sequence ();
5517 emit_insn_before (seq, parm_birth_insn);
5518
5519 emit_stack_restore (SAVE_FUNCTION, tem);
5520 }
5521
5522 /* ??? This should no longer be necessary since stupid is no longer with
5523 us, but there are some parts of the compiler (eg reload_combine, and
5524 sh mach_dep_reorg) that still try and compute their own lifetime info
5525 instead of using the general framework. */
5526 use_return_register ();
5527 }
5528
5529 rtx
5530 get_arg_pointer_save_area (void)
5531 {
5532 rtx ret = arg_pointer_save_area;
5533
5534 if (! ret)
5535 {
5536 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5537 arg_pointer_save_area = ret;
5538 }
5539
5540 if (! crtl->arg_pointer_save_area_init)
5541 {
5542 /* Save the arg pointer at the beginning of the function. The
5543 generated stack slot may not be a valid memory address, so we
5544 have to check it and fix it if necessary. */
5545 start_sequence ();
5546 emit_move_insn (validize_mem (copy_rtx (ret)),
5547 crtl->args.internal_arg_pointer);
5548 rtx_insn *seq = get_insns ();
5549 end_sequence ();
5550
5551 push_topmost_sequence ();
5552 emit_insn_after (seq, entry_of_function ());
5553 pop_topmost_sequence ();
5554
5555 crtl->arg_pointer_save_area_init = true;
5556 }
5557
5558 return ret;
5559 }
5560 \f
5561
5562 /* If debugging dumps are requested, dump information about how the
5563 target handled -fstack-check=clash for the prologue.
5564
5565 PROBES describes what if any probes were emitted.
5566
5567 RESIDUALS indicates if the prologue had any residual allocation
5568 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5569
5570 void
5571 dump_stack_clash_frame_info (enum stack_clash_probes probes, bool residuals)
5572 {
5573 if (!dump_file)
5574 return;
5575
5576 switch (probes)
5577 {
5578 case NO_PROBE_NO_FRAME:
5579 fprintf (dump_file,
5580 "Stack clash no probe no stack adjustment in prologue.\n");
5581 break;
5582 case NO_PROBE_SMALL_FRAME:
5583 fprintf (dump_file,
5584 "Stack clash no probe small stack adjustment in prologue.\n");
5585 break;
5586 case PROBE_INLINE:
5587 fprintf (dump_file, "Stack clash inline probes in prologue.\n");
5588 break;
5589 case PROBE_LOOP:
5590 fprintf (dump_file, "Stack clash probe loop in prologue.\n");
5591 break;
5592 }
5593
5594 if (residuals)
5595 fprintf (dump_file, "Stack clash residual allocation in prologue.\n");
5596 else
5597 fprintf (dump_file, "Stack clash no residual allocation in prologue.\n");
5598
5599 if (frame_pointer_needed)
5600 fprintf (dump_file, "Stack clash frame pointer needed.\n");
5601 else
5602 fprintf (dump_file, "Stack clash no frame pointer needed.\n");
5603
5604 if (TREE_THIS_VOLATILE (cfun->decl))
5605 fprintf (dump_file,
5606 "Stack clash noreturn prologue, assuming no implicit"
5607 " probes in caller.\n");
5608 else
5609 fprintf (dump_file,
5610 "Stack clash not noreturn prologue.\n");
5611 }
5612
5613 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5614 for the first time. */
5615
5616 static void
5617 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5618 {
5619 rtx_insn *tmp;
5620 hash_table<insn_cache_hasher> *hash = *hashp;
5621
5622 if (hash == NULL)
5623 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5624
5625 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5626 {
5627 rtx *slot = hash->find_slot (tmp, INSERT);
5628 gcc_assert (*slot == NULL);
5629 *slot = tmp;
5630 }
5631 }
5632
5633 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5634 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5635 insn, then record COPY as well. */
5636
5637 void
5638 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5639 {
5640 hash_table<insn_cache_hasher> *hash;
5641 rtx *slot;
5642
5643 hash = epilogue_insn_hash;
5644 if (!hash || !hash->find (insn))
5645 {
5646 hash = prologue_insn_hash;
5647 if (!hash || !hash->find (insn))
5648 return;
5649 }
5650
5651 slot = hash->find_slot (copy, INSERT);
5652 gcc_assert (*slot == NULL);
5653 *slot = copy;
5654 }
5655
5656 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5657 we can be running after reorg, SEQUENCE rtl is possible. */
5658
5659 static bool
5660 contains (const rtx_insn *insn, hash_table<insn_cache_hasher> *hash)
5661 {
5662 if (hash == NULL)
5663 return false;
5664
5665 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5666 {
5667 rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn));
5668 int i;
5669 for (i = seq->len () - 1; i >= 0; i--)
5670 if (hash->find (seq->element (i)))
5671 return true;
5672 return false;
5673 }
5674
5675 return hash->find (const_cast<rtx_insn *> (insn)) != NULL;
5676 }
5677
5678 int
5679 prologue_contains (const rtx_insn *insn)
5680 {
5681 return contains (insn, prologue_insn_hash);
5682 }
5683
5684 int
5685 epilogue_contains (const rtx_insn *insn)
5686 {
5687 return contains (insn, epilogue_insn_hash);
5688 }
5689
5690 int
5691 prologue_epilogue_contains (const rtx_insn *insn)
5692 {
5693 if (contains (insn, prologue_insn_hash))
5694 return 1;
5695 if (contains (insn, epilogue_insn_hash))
5696 return 1;
5697 return 0;
5698 }
5699
5700 void
5701 record_prologue_seq (rtx_insn *seq)
5702 {
5703 record_insns (seq, NULL, &prologue_insn_hash);
5704 }
5705
5706 void
5707 record_epilogue_seq (rtx_insn *seq)
5708 {
5709 record_insns (seq, NULL, &epilogue_insn_hash);
5710 }
5711
5712 /* Set JUMP_LABEL for a return insn. */
5713
5714 void
5715 set_return_jump_label (rtx_insn *returnjump)
5716 {
5717 rtx pat = PATTERN (returnjump);
5718 if (GET_CODE (pat) == PARALLEL)
5719 pat = XVECEXP (pat, 0, 0);
5720 if (ANY_RETURN_P (pat))
5721 JUMP_LABEL (returnjump) = pat;
5722 else
5723 JUMP_LABEL (returnjump) = ret_rtx;
5724 }
5725
5726 /* Return a sequence to be used as the split prologue for the current
5727 function, or NULL. */
5728
5729 static rtx_insn *
5730 make_split_prologue_seq (void)
5731 {
5732 if (!flag_split_stack
5733 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl)))
5734 return NULL;
5735
5736 start_sequence ();
5737 emit_insn (targetm.gen_split_stack_prologue ());
5738 rtx_insn *seq = get_insns ();
5739 end_sequence ();
5740
5741 record_insns (seq, NULL, &prologue_insn_hash);
5742 set_insn_locations (seq, prologue_location);
5743
5744 return seq;
5745 }
5746
5747 /* Return a sequence to be used as the prologue for the current function,
5748 or NULL. */
5749
5750 static rtx_insn *
5751 make_prologue_seq (void)
5752 {
5753 if (!targetm.have_prologue ())
5754 return NULL;
5755
5756 start_sequence ();
5757 rtx_insn *seq = targetm.gen_prologue ();
5758 emit_insn (seq);
5759
5760 /* Insert an explicit USE for the frame pointer
5761 if the profiling is on and the frame pointer is required. */
5762 if (crtl->profile && frame_pointer_needed)
5763 emit_use (hard_frame_pointer_rtx);
5764
5765 /* Retain a map of the prologue insns. */
5766 record_insns (seq, NULL, &prologue_insn_hash);
5767 emit_note (NOTE_INSN_PROLOGUE_END);
5768
5769 /* Ensure that instructions are not moved into the prologue when
5770 profiling is on. The call to the profiling routine can be
5771 emitted within the live range of a call-clobbered register. */
5772 if (!targetm.profile_before_prologue () && crtl->profile)
5773 emit_insn (gen_blockage ());
5774
5775 seq = get_insns ();
5776 end_sequence ();
5777 set_insn_locations (seq, prologue_location);
5778
5779 return seq;
5780 }
5781
5782 /* Return a sequence to be used as the epilogue for the current function,
5783 or NULL. */
5784
5785 static rtx_insn *
5786 make_epilogue_seq (void)
5787 {
5788 if (!targetm.have_epilogue ())
5789 return NULL;
5790
5791 start_sequence ();
5792 emit_note (NOTE_INSN_EPILOGUE_BEG);
5793 rtx_insn *seq = targetm.gen_epilogue ();
5794 if (seq)
5795 emit_jump_insn (seq);
5796
5797 /* Retain a map of the epilogue insns. */
5798 record_insns (seq, NULL, &epilogue_insn_hash);
5799 set_insn_locations (seq, epilogue_location);
5800
5801 seq = get_insns ();
5802 rtx_insn *returnjump = get_last_insn ();
5803 end_sequence ();
5804
5805 if (JUMP_P (returnjump))
5806 set_return_jump_label (returnjump);
5807
5808 return seq;
5809 }
5810
5811
5812 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5813 this into place with notes indicating where the prologue ends and where
5814 the epilogue begins. Update the basic block information when possible.
5815
5816 Notes on epilogue placement:
5817 There are several kinds of edges to the exit block:
5818 * a single fallthru edge from LAST_BB
5819 * possibly, edges from blocks containing sibcalls
5820 * possibly, fake edges from infinite loops
5821
5822 The epilogue is always emitted on the fallthru edge from the last basic
5823 block in the function, LAST_BB, into the exit block.
5824
5825 If LAST_BB is empty except for a label, it is the target of every
5826 other basic block in the function that ends in a return. If a
5827 target has a return or simple_return pattern (possibly with
5828 conditional variants), these basic blocks can be changed so that a
5829 return insn is emitted into them, and their target is adjusted to
5830 the real exit block.
5831
5832 Notes on shrink wrapping: We implement a fairly conservative
5833 version of shrink-wrapping rather than the textbook one. We only
5834 generate a single prologue and a single epilogue. This is
5835 sufficient to catch a number of interesting cases involving early
5836 exits.
5837
5838 First, we identify the blocks that require the prologue to occur before
5839 them. These are the ones that modify a call-saved register, or reference
5840 any of the stack or frame pointer registers. To simplify things, we then
5841 mark everything reachable from these blocks as also requiring a prologue.
5842 This takes care of loops automatically, and avoids the need to examine
5843 whether MEMs reference the frame, since it is sufficient to check for
5844 occurrences of the stack or frame pointer.
5845
5846 We then compute the set of blocks for which the need for a prologue
5847 is anticipatable (borrowing terminology from the shrink-wrapping
5848 description in Muchnick's book). These are the blocks which either
5849 require a prologue themselves, or those that have only successors
5850 where the prologue is anticipatable. The prologue needs to be
5851 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5852 is not. For the moment, we ensure that only one such edge exists.
5853
5854 The epilogue is placed as described above, but we make a
5855 distinction between inserting return and simple_return patterns
5856 when modifying other blocks that end in a return. Blocks that end
5857 in a sibcall omit the sibcall_epilogue if the block is not in
5858 ANTIC. */
5859
5860 void
5861 thread_prologue_and_epilogue_insns (void)
5862 {
5863 df_analyze ();
5864
5865 /* Can't deal with multiple successors of the entry block at the
5866 moment. Function should always have at least one entry
5867 point. */
5868 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
5869
5870 edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5871 edge orig_entry_edge = entry_edge;
5872
5873 rtx_insn *split_prologue_seq = make_split_prologue_seq ();
5874 rtx_insn *prologue_seq = make_prologue_seq ();
5875 rtx_insn *epilogue_seq = make_epilogue_seq ();
5876
5877 /* Try to perform a kind of shrink-wrapping, making sure the
5878 prologue/epilogue is emitted only around those parts of the
5879 function that require it. */
5880 try_shrink_wrapping (&entry_edge, prologue_seq);
5881
5882 /* If the target can handle splitting the prologue/epilogue into separate
5883 components, try to shrink-wrap these components separately. */
5884 try_shrink_wrapping_separate (entry_edge->dest);
5885
5886 /* If that did anything for any component we now need the generate the
5887 "main" prologue again. Because some targets require some of these
5888 to be called in a specific order (i386 requires the split prologue
5889 to be first, for example), we create all three sequences again here.
5890 If this does not work for some target, that target should not enable
5891 separate shrink-wrapping. */
5892 if (crtl->shrink_wrapped_separate)
5893 {
5894 split_prologue_seq = make_split_prologue_seq ();
5895 prologue_seq = make_prologue_seq ();
5896 epilogue_seq = make_epilogue_seq ();
5897 }
5898
5899 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
5900
5901 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5902 this marker for the splits of EH_RETURN patterns, and nothing else
5903 uses the flag in the meantime. */
5904 epilogue_completed = 1;
5905
5906 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5907 some targets, these get split to a special version of the epilogue
5908 code. In order to be able to properly annotate these with unwind
5909 info, try to split them now. If we get a valid split, drop an
5910 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5911 edge e;
5912 edge_iterator ei;
5913 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5914 {
5915 rtx_insn *prev, *last, *trial;
5916
5917 if (e->flags & EDGE_FALLTHRU)
5918 continue;
5919 last = BB_END (e->src);
5920 if (!eh_returnjump_p (last))
5921 continue;
5922
5923 prev = PREV_INSN (last);
5924 trial = try_split (PATTERN (last), last, 1);
5925 if (trial == last)
5926 continue;
5927
5928 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5929 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5930 }
5931
5932 edge exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
5933
5934 if (exit_fallthru_edge)
5935 {
5936 if (epilogue_seq)
5937 {
5938 insert_insn_on_edge (epilogue_seq, exit_fallthru_edge);
5939 commit_edge_insertions ();
5940
5941 /* The epilogue insns we inserted may cause the exit edge to no longer
5942 be fallthru. */
5943 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5944 {
5945 if (((e->flags & EDGE_FALLTHRU) != 0)
5946 && returnjump_p (BB_END (e->src)))
5947 e->flags &= ~EDGE_FALLTHRU;
5948 }
5949 }
5950 else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
5951 {
5952 /* We have a fall-through edge to the exit block, the source is not
5953 at the end of the function, and there will be an assembler epilogue
5954 at the end of the function.
5955 We can't use force_nonfallthru here, because that would try to
5956 use return. Inserting a jump 'by hand' is extremely messy, so
5957 we take advantage of cfg_layout_finalize using
5958 fixup_fallthru_exit_predecessor. */
5959 cfg_layout_initialize (0);
5960 basic_block cur_bb;
5961 FOR_EACH_BB_FN (cur_bb, cfun)
5962 if (cur_bb->index >= NUM_FIXED_BLOCKS
5963 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5964 cur_bb->aux = cur_bb->next_bb;
5965 cfg_layout_finalize ();
5966 }
5967 }
5968
5969 /* Insert the prologue. */
5970
5971 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5972
5973 if (split_prologue_seq || prologue_seq)
5974 {
5975 rtx_insn *split_prologue_insn = split_prologue_seq;
5976 if (split_prologue_seq)
5977 {
5978 while (split_prologue_insn && !NONDEBUG_INSN_P (split_prologue_insn))
5979 split_prologue_insn = NEXT_INSN (split_prologue_insn);
5980 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
5981 }
5982
5983 rtx_insn *prologue_insn = prologue_seq;
5984 if (prologue_seq)
5985 {
5986 while (prologue_insn && !NONDEBUG_INSN_P (prologue_insn))
5987 prologue_insn = NEXT_INSN (prologue_insn);
5988 insert_insn_on_edge (prologue_seq, entry_edge);
5989 }
5990
5991 commit_edge_insertions ();
5992
5993 /* Look for basic blocks within the prologue insns. */
5994 if (split_prologue_insn
5995 && BLOCK_FOR_INSN (split_prologue_insn) == NULL)
5996 split_prologue_insn = NULL;
5997 if (prologue_insn
5998 && BLOCK_FOR_INSN (prologue_insn) == NULL)
5999 prologue_insn = NULL;
6000 if (split_prologue_insn || prologue_insn)
6001 {
6002 auto_sbitmap blocks (last_basic_block_for_fn (cfun));
6003 bitmap_clear (blocks);
6004 if (split_prologue_insn)
6005 bitmap_set_bit (blocks,
6006 BLOCK_FOR_INSN (split_prologue_insn)->index);
6007 if (prologue_insn)
6008 bitmap_set_bit (blocks, BLOCK_FOR_INSN (prologue_insn)->index);
6009 find_many_sub_basic_blocks (blocks);
6010 }
6011 }
6012
6013 default_rtl_profile ();
6014
6015 /* Emit sibling epilogues before any sibling call sites. */
6016 for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6017 (e = ei_safe_edge (ei));
6018 ei_next (&ei))
6019 {
6020 /* Skip those already handled, the ones that run without prologue. */
6021 if (e->flags & EDGE_IGNORE)
6022 {
6023 e->flags &= ~EDGE_IGNORE;
6024 continue;
6025 }
6026
6027 rtx_insn *insn = BB_END (e->src);
6028
6029 if (!(CALL_P (insn) && SIBLING_CALL_P (insn)))
6030 continue;
6031
6032 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6033 {
6034 start_sequence ();
6035 emit_note (NOTE_INSN_EPILOGUE_BEG);
6036 emit_insn (ep_seq);
6037 rtx_insn *seq = get_insns ();
6038 end_sequence ();
6039
6040 /* Retain a map of the epilogue insns. Used in life analysis to
6041 avoid getting rid of sibcall epilogue insns. Do this before we
6042 actually emit the sequence. */
6043 record_insns (seq, NULL, &epilogue_insn_hash);
6044 set_insn_locations (seq, epilogue_location);
6045
6046 emit_insn_before (seq, insn);
6047 }
6048 }
6049
6050 if (epilogue_seq)
6051 {
6052 rtx_insn *insn, *next;
6053
6054 /* Similarly, move any line notes that appear after the epilogue.
6055 There is no need, however, to be quite so anal about the existence
6056 of such a note. Also possibly move
6057 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6058 info generation. */
6059 for (insn = epilogue_seq; insn; insn = next)
6060 {
6061 next = NEXT_INSN (insn);
6062 if (NOTE_P (insn)
6063 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6064 reorder_insns (insn, insn, PREV_INSN (epilogue_seq));
6065 }
6066 }
6067
6068 /* Threading the prologue and epilogue changes the artificial refs
6069 in the entry and exit blocks. */
6070 epilogue_completed = 1;
6071 df_update_entry_exit_and_calls ();
6072 }
6073
6074 /* Reposition the prologue-end and epilogue-begin notes after
6075 instruction scheduling. */
6076
6077 void
6078 reposition_prologue_and_epilogue_notes (void)
6079 {
6080 if (!targetm.have_prologue ()
6081 && !targetm.have_epilogue ()
6082 && !targetm.have_sibcall_epilogue ())
6083 return;
6084
6085 /* Since the hash table is created on demand, the fact that it is
6086 non-null is a signal that it is non-empty. */
6087 if (prologue_insn_hash != NULL)
6088 {
6089 size_t len = prologue_insn_hash->elements ();
6090 rtx_insn *insn, *last = NULL, *note = NULL;
6091
6092 /* Scan from the beginning until we reach the last prologue insn. */
6093 /* ??? While we do have the CFG intact, there are two problems:
6094 (1) The prologue can contain loops (typically probing the stack),
6095 which means that the end of the prologue isn't in the first bb.
6096 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6097 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6098 {
6099 if (NOTE_P (insn))
6100 {
6101 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6102 note = insn;
6103 }
6104 else if (contains (insn, prologue_insn_hash))
6105 {
6106 last = insn;
6107 if (--len == 0)
6108 break;
6109 }
6110 }
6111
6112 if (last)
6113 {
6114 if (note == NULL)
6115 {
6116 /* Scan forward looking for the PROLOGUE_END note. It should
6117 be right at the beginning of the block, possibly with other
6118 insn notes that got moved there. */
6119 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6120 {
6121 if (NOTE_P (note)
6122 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6123 break;
6124 }
6125 }
6126
6127 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6128 if (LABEL_P (last))
6129 last = NEXT_INSN (last);
6130 reorder_insns (note, note, last);
6131 }
6132 }
6133
6134 if (epilogue_insn_hash != NULL)
6135 {
6136 edge_iterator ei;
6137 edge e;
6138
6139 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6140 {
6141 rtx_insn *insn, *first = NULL, *note = NULL;
6142 basic_block bb = e->src;
6143
6144 /* Scan from the beginning until we reach the first epilogue insn. */
6145 FOR_BB_INSNS (bb, insn)
6146 {
6147 if (NOTE_P (insn))
6148 {
6149 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6150 {
6151 note = insn;
6152 if (first != NULL)
6153 break;
6154 }
6155 }
6156 else if (first == NULL && contains (insn, epilogue_insn_hash))
6157 {
6158 first = insn;
6159 if (note != NULL)
6160 break;
6161 }
6162 }
6163
6164 if (note)
6165 {
6166 /* If the function has a single basic block, and no real
6167 epilogue insns (e.g. sibcall with no cleanup), the
6168 epilogue note can get scheduled before the prologue
6169 note. If we have frame related prologue insns, having
6170 them scanned during the epilogue will result in a crash.
6171 In this case re-order the epilogue note to just before
6172 the last insn in the block. */
6173 if (first == NULL)
6174 first = BB_END (bb);
6175
6176 if (PREV_INSN (first) != note)
6177 reorder_insns (note, note, PREV_INSN (first));
6178 }
6179 }
6180 }
6181 }
6182
6183 /* Returns the name of function declared by FNDECL. */
6184 const char *
6185 fndecl_name (tree fndecl)
6186 {
6187 if (fndecl == NULL)
6188 return "(nofn)";
6189 return lang_hooks.decl_printable_name (fndecl, 1);
6190 }
6191
6192 /* Returns the name of function FN. */
6193 const char *
6194 function_name (struct function *fn)
6195 {
6196 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6197 return fndecl_name (fndecl);
6198 }
6199
6200 /* Returns the name of the current function. */
6201 const char *
6202 current_function_name (void)
6203 {
6204 return function_name (cfun);
6205 }
6206 \f
6207
6208 static unsigned int
6209 rest_of_handle_check_leaf_regs (void)
6210 {
6211 #ifdef LEAF_REGISTERS
6212 crtl->uses_only_leaf_regs
6213 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6214 #endif
6215 return 0;
6216 }
6217
6218 /* Insert a TYPE into the used types hash table of CFUN. */
6219
6220 static void
6221 used_types_insert_helper (tree type, struct function *func)
6222 {
6223 if (type != NULL && func != NULL)
6224 {
6225 if (func->used_types_hash == NULL)
6226 func->used_types_hash = hash_set<tree>::create_ggc (37);
6227
6228 func->used_types_hash->add (type);
6229 }
6230 }
6231
6232 /* Given a type, insert it into the used hash table in cfun. */
6233 void
6234 used_types_insert (tree t)
6235 {
6236 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6237 if (TYPE_NAME (t))
6238 break;
6239 else
6240 t = TREE_TYPE (t);
6241 if (TREE_CODE (t) == ERROR_MARK)
6242 return;
6243 if (TYPE_NAME (t) == NULL_TREE
6244 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6245 t = TYPE_MAIN_VARIANT (t);
6246 if (debug_info_level > DINFO_LEVEL_NONE)
6247 {
6248 if (cfun)
6249 used_types_insert_helper (t, cfun);
6250 else
6251 {
6252 /* So this might be a type referenced by a global variable.
6253 Record that type so that we can later decide to emit its
6254 debug information. */
6255 vec_safe_push (types_used_by_cur_var_decl, t);
6256 }
6257 }
6258 }
6259
6260 /* Helper to Hash a struct types_used_by_vars_entry. */
6261
6262 static hashval_t
6263 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6264 {
6265 gcc_assert (entry && entry->var_decl && entry->type);
6266
6267 return iterative_hash_object (entry->type,
6268 iterative_hash_object (entry->var_decl, 0));
6269 }
6270
6271 /* Hash function of the types_used_by_vars_entry hash table. */
6272
6273 hashval_t
6274 used_type_hasher::hash (types_used_by_vars_entry *entry)
6275 {
6276 return hash_types_used_by_vars_entry (entry);
6277 }
6278
6279 /*Equality function of the types_used_by_vars_entry hash table. */
6280
6281 bool
6282 used_type_hasher::equal (types_used_by_vars_entry *e1,
6283 types_used_by_vars_entry *e2)
6284 {
6285 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6286 }
6287
6288 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6289
6290 void
6291 types_used_by_var_decl_insert (tree type, tree var_decl)
6292 {
6293 if (type != NULL && var_decl != NULL)
6294 {
6295 types_used_by_vars_entry **slot;
6296 struct types_used_by_vars_entry e;
6297 e.var_decl = var_decl;
6298 e.type = type;
6299 if (types_used_by_vars_hash == NULL)
6300 types_used_by_vars_hash
6301 = hash_table<used_type_hasher>::create_ggc (37);
6302
6303 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6304 if (*slot == NULL)
6305 {
6306 struct types_used_by_vars_entry *entry;
6307 entry = ggc_alloc<types_used_by_vars_entry> ();
6308 entry->type = type;
6309 entry->var_decl = var_decl;
6310 *slot = entry;
6311 }
6312 }
6313 }
6314
6315 namespace {
6316
6317 const pass_data pass_data_leaf_regs =
6318 {
6319 RTL_PASS, /* type */
6320 "*leaf_regs", /* name */
6321 OPTGROUP_NONE, /* optinfo_flags */
6322 TV_NONE, /* tv_id */
6323 0, /* properties_required */
6324 0, /* properties_provided */
6325 0, /* properties_destroyed */
6326 0, /* todo_flags_start */
6327 0, /* todo_flags_finish */
6328 };
6329
6330 class pass_leaf_regs : public rtl_opt_pass
6331 {
6332 public:
6333 pass_leaf_regs (gcc::context *ctxt)
6334 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6335 {}
6336
6337 /* opt_pass methods: */
6338 virtual unsigned int execute (function *)
6339 {
6340 return rest_of_handle_check_leaf_regs ();
6341 }
6342
6343 }; // class pass_leaf_regs
6344
6345 } // anon namespace
6346
6347 rtl_opt_pass *
6348 make_pass_leaf_regs (gcc::context *ctxt)
6349 {
6350 return new pass_leaf_regs (ctxt);
6351 }
6352
6353 static unsigned int
6354 rest_of_handle_thread_prologue_and_epilogue (void)
6355 {
6356 /* prepare_shrink_wrap is sensitive to the block structure of the control
6357 flow graph, so clean it up first. */
6358 if (optimize)
6359 cleanup_cfg (0);
6360
6361 /* On some machines, the prologue and epilogue code, or parts thereof,
6362 can be represented as RTL. Doing so lets us schedule insns between
6363 it and the rest of the code and also allows delayed branch
6364 scheduling to operate in the epilogue. */
6365 thread_prologue_and_epilogue_insns ();
6366
6367 /* Some non-cold blocks may now be only reachable from cold blocks.
6368 Fix that up. */
6369 fixup_partitions ();
6370
6371 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6372 see PR57320. */
6373 cleanup_cfg (optimize ? CLEANUP_EXPENSIVE : 0);
6374
6375 /* The stack usage info is finalized during prologue expansion. */
6376 if (flag_stack_usage_info)
6377 output_stack_usage ();
6378
6379 return 0;
6380 }
6381
6382 namespace {
6383
6384 const pass_data pass_data_thread_prologue_and_epilogue =
6385 {
6386 RTL_PASS, /* type */
6387 "pro_and_epilogue", /* name */
6388 OPTGROUP_NONE, /* optinfo_flags */
6389 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6390 0, /* properties_required */
6391 0, /* properties_provided */
6392 0, /* properties_destroyed */
6393 0, /* todo_flags_start */
6394 ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
6395 };
6396
6397 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6398 {
6399 public:
6400 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6401 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6402 {}
6403
6404 /* opt_pass methods: */
6405 virtual unsigned int execute (function *)
6406 {
6407 return rest_of_handle_thread_prologue_and_epilogue ();
6408 }
6409
6410 }; // class pass_thread_prologue_and_epilogue
6411
6412 } // anon namespace
6413
6414 rtl_opt_pass *
6415 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6416 {
6417 return new pass_thread_prologue_and_epilogue (ctxt);
6418 }
6419 \f
6420
6421 /* If CONSTRAINT is a matching constraint, then return its number.
6422 Otherwise, return -1. */
6423
6424 static int
6425 matching_constraint_num (const char *constraint)
6426 {
6427 if (*constraint == '%')
6428 constraint++;
6429
6430 if (IN_RANGE (*constraint, '0', '9'))
6431 return strtoul (constraint, NULL, 10);
6432
6433 return -1;
6434 }
6435
6436 /* This mini-pass fixes fall-out from SSA in asm statements that have
6437 in-out constraints. Say you start with
6438
6439 orig = inout;
6440 asm ("": "+mr" (inout));
6441 use (orig);
6442
6443 which is transformed very early to use explicit output and match operands:
6444
6445 orig = inout;
6446 asm ("": "=mr" (inout) : "0" (inout));
6447 use (orig);
6448
6449 Or, after SSA and copyprop,
6450
6451 asm ("": "=mr" (inout_2) : "0" (inout_1));
6452 use (inout_1);
6453
6454 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6455 they represent two separate values, so they will get different pseudo
6456 registers during expansion. Then, since the two operands need to match
6457 per the constraints, but use different pseudo registers, reload can
6458 only register a reload for these operands. But reloads can only be
6459 satisfied by hardregs, not by memory, so we need a register for this
6460 reload, just because we are presented with non-matching operands.
6461 So, even though we allow memory for this operand, no memory can be
6462 used for it, just because the two operands don't match. This can
6463 cause reload failures on register-starved targets.
6464
6465 So it's a symptom of reload not being able to use memory for reloads
6466 or, alternatively it's also a symptom of both operands not coming into
6467 reload as matching (in which case the pseudo could go to memory just
6468 fine, as the alternative allows it, and no reload would be necessary).
6469 We fix the latter problem here, by transforming
6470
6471 asm ("": "=mr" (inout_2) : "0" (inout_1));
6472
6473 back to
6474
6475 inout_2 = inout_1;
6476 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6477
6478 static void
6479 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
6480 {
6481 int i;
6482 bool changed = false;
6483 rtx op = SET_SRC (p_sets[0]);
6484 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6485 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6486 bool *output_matched = XALLOCAVEC (bool, noutputs);
6487
6488 memset (output_matched, 0, noutputs * sizeof (bool));
6489 for (i = 0; i < ninputs; i++)
6490 {
6491 rtx input, output;
6492 rtx_insn *insns;
6493 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6494 int match, j;
6495
6496 match = matching_constraint_num (constraint);
6497 if (match < 0)
6498 continue;
6499
6500 gcc_assert (match < noutputs);
6501 output = SET_DEST (p_sets[match]);
6502 input = RTVEC_ELT (inputs, i);
6503 /* Only do the transformation for pseudos. */
6504 if (! REG_P (output)
6505 || rtx_equal_p (output, input)
6506 || !(REG_P (input) || SUBREG_P (input)
6507 || MEM_P (input) || CONSTANT_P (input))
6508 || !general_operand (input, GET_MODE (output)))
6509 continue;
6510
6511 /* We can't do anything if the output is also used as input,
6512 as we're going to overwrite it. */
6513 for (j = 0; j < ninputs; j++)
6514 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6515 break;
6516 if (j != ninputs)
6517 continue;
6518
6519 /* Avoid changing the same input several times. For
6520 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6521 only change it once (to out1), rather than changing it
6522 first to out1 and afterwards to out2. */
6523 if (i > 0)
6524 {
6525 for (j = 0; j < noutputs; j++)
6526 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6527 break;
6528 if (j != noutputs)
6529 continue;
6530 }
6531 output_matched[match] = true;
6532
6533 start_sequence ();
6534 emit_move_insn (output, copy_rtx (input));
6535 insns = get_insns ();
6536 end_sequence ();
6537 emit_insn_before (insns, insn);
6538
6539 constraint = ASM_OPERANDS_OUTPUT_CONSTRAINT(SET_SRC(p_sets[match]));
6540 bool early_clobber_p = strchr (constraint, '&') != NULL;
6541
6542 /* Now replace all mentions of the input with output. We can't
6543 just replace the occurrence in inputs[i], as the register might
6544 also be used in some other input (or even in an address of an
6545 output), which would mean possibly increasing the number of
6546 inputs by one (namely 'output' in addition), which might pose
6547 a too complicated problem for reload to solve. E.g. this situation:
6548
6549 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6550
6551 Here 'input' is used in two occurrences as input (once for the
6552 input operand, once for the address in the second output operand).
6553 If we would replace only the occurrence of the input operand (to
6554 make the matching) we would be left with this:
6555
6556 output = input
6557 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6558
6559 Now we suddenly have two different input values (containing the same
6560 value, but different pseudos) where we formerly had only one.
6561 With more complicated asms this might lead to reload failures
6562 which wouldn't have happen without this pass. So, iterate over
6563 all operands and replace all occurrences of the register used.
6564
6565 However, if one or more of the 'input' uses have a non-matching
6566 constraint and the matched output operand is an early clobber
6567 operand, then do not replace the input operand, since by definition
6568 it conflicts with the output operand and cannot share the same
6569 register. See PR89313 for details. */
6570
6571 for (j = 0; j < noutputs; j++)
6572 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6573 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6574 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6575 input, output);
6576 for (j = 0; j < ninputs; j++)
6577 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6578 {
6579 if (!early_clobber_p
6580 || match == matching_constraint_num
6581 (ASM_OPERANDS_INPUT_CONSTRAINT (op, j)))
6582 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6583 input, output);
6584 }
6585
6586 changed = true;
6587 }
6588
6589 if (changed)
6590 df_insn_rescan (insn);
6591 }
6592
6593 /* Add the decl D to the local_decls list of FUN. */
6594
6595 void
6596 add_local_decl (struct function *fun, tree d)
6597 {
6598 gcc_assert (VAR_P (d));
6599 vec_safe_push (fun->local_decls, d);
6600 }
6601
6602 namespace {
6603
6604 const pass_data pass_data_match_asm_constraints =
6605 {
6606 RTL_PASS, /* type */
6607 "asmcons", /* name */
6608 OPTGROUP_NONE, /* optinfo_flags */
6609 TV_NONE, /* tv_id */
6610 0, /* properties_required */
6611 0, /* properties_provided */
6612 0, /* properties_destroyed */
6613 0, /* todo_flags_start */
6614 0, /* todo_flags_finish */
6615 };
6616
6617 class pass_match_asm_constraints : public rtl_opt_pass
6618 {
6619 public:
6620 pass_match_asm_constraints (gcc::context *ctxt)
6621 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6622 {}
6623
6624 /* opt_pass methods: */
6625 virtual unsigned int execute (function *);
6626
6627 }; // class pass_match_asm_constraints
6628
6629 unsigned
6630 pass_match_asm_constraints::execute (function *fun)
6631 {
6632 basic_block bb;
6633 rtx_insn *insn;
6634 rtx pat, *p_sets;
6635 int noutputs;
6636
6637 if (!crtl->has_asm_statement)
6638 return 0;
6639
6640 df_set_flags (DF_DEFER_INSN_RESCAN);
6641 FOR_EACH_BB_FN (bb, fun)
6642 {
6643 FOR_BB_INSNS (bb, insn)
6644 {
6645 if (!INSN_P (insn))
6646 continue;
6647
6648 pat = PATTERN (insn);
6649 if (GET_CODE (pat) == PARALLEL)
6650 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6651 else if (GET_CODE (pat) == SET)
6652 p_sets = &PATTERN (insn), noutputs = 1;
6653 else
6654 continue;
6655
6656 if (GET_CODE (*p_sets) == SET
6657 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6658 match_asm_constraints_1 (insn, p_sets, noutputs);
6659 }
6660 }
6661
6662 return TODO_df_finish;
6663 }
6664
6665 } // anon namespace
6666
6667 rtl_opt_pass *
6668 make_pass_match_asm_constraints (gcc::context *ctxt)
6669 {
6670 return new pass_match_asm_constraints (ctxt);
6671 }
6672
6673
6674 #include "gt-function.h"