re PR debug/91929 (missing inline subroutine information in build using sin/cos)
[official-gcc.git] / gcc / function.c
bloba1c76a4dd7a84554f746c6ab99717cfe54ed0390
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2019 Free Software Foundation, Inc.
4 This file is part of GCC.
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.
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.
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/>. */
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.
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.
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. */
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 #include "function-abi.h"
84 /* So we can assign to cfun in this file. */
85 #undef cfun
87 #ifndef STACK_ALIGNMENT_NEEDED
88 #define STACK_ALIGNMENT_NEEDED 1
89 #endif
91 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
93 /* Round a value to the lowest integer less than it that is a multiple of
94 the required alignment. Avoid using division in case the value is
95 negative. Assume the alignment is a power of two. */
96 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
98 /* Similar, but round to the next highest integer that meets the
99 alignment. */
100 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
102 /* Nonzero once virtual register instantiation has been done.
103 assign_stack_local uses frame_pointer_rtx when this is nonzero.
104 calls.c:emit_library_call_value_1 uses it to set up
105 post-instantiation libcalls. */
106 int virtuals_instantiated;
108 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
109 static GTY(()) int funcdef_no;
111 /* These variables hold pointers to functions to create and destroy
112 target specific, per-function data structures. */
113 struct machine_function * (*init_machine_status) (void);
115 /* The currently compiled function. */
116 struct function *cfun = 0;
118 /* These hashes record the prologue and epilogue insns. */
120 struct insn_cache_hasher : ggc_cache_ptr_hash<rtx_def>
122 static hashval_t hash (rtx x) { return htab_hash_pointer (x); }
123 static bool equal (rtx a, rtx b) { return a == b; }
126 static GTY((cache))
127 hash_table<insn_cache_hasher> *prologue_insn_hash;
128 static GTY((cache))
129 hash_table<insn_cache_hasher> *epilogue_insn_hash;
132 hash_table<used_type_hasher> *types_used_by_vars_hash = NULL;
133 vec<tree, va_gc> *types_used_by_cur_var_decl;
135 /* Forward declarations. */
137 static class temp_slot *find_temp_slot_from_address (rtx);
138 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
139 static void pad_below (struct args_size *, machine_mode, tree);
140 static void reorder_blocks_1 (rtx_insn *, tree, vec<tree> *);
141 static int all_blocks (tree, tree *);
142 static tree *get_block_vector (tree, int *);
143 extern tree debug_find_var_in_block_tree (tree, tree);
144 /* We always define `record_insns' even if it's not used so that we
145 can always export `prologue_epilogue_contains'. */
146 static void record_insns (rtx_insn *, rtx, hash_table<insn_cache_hasher> **)
147 ATTRIBUTE_UNUSED;
148 static bool contains (const rtx_insn *, hash_table<insn_cache_hasher> *);
149 static void prepare_function_start (void);
150 static void do_clobber_return_reg (rtx, void *);
151 static void do_use_return_reg (rtx, void *);
154 /* Stack of nested functions. */
155 /* Keep track of the cfun stack. */
157 static vec<function *> function_context_stack;
159 /* Save the current context for compilation of a nested function.
160 This is called from language-specific code. */
162 void
163 push_function_context (void)
165 if (cfun == 0)
166 allocate_struct_function (NULL, false);
168 function_context_stack.safe_push (cfun);
169 set_cfun (NULL);
172 /* Restore the last saved context, at the end of a nested function.
173 This function is called from language-specific code. */
175 void
176 pop_function_context (void)
178 struct function *p = function_context_stack.pop ();
179 set_cfun (p);
180 current_function_decl = p->decl;
182 /* Reset variables that have known state during rtx generation. */
183 virtuals_instantiated = 0;
184 generating_concat_p = 1;
187 /* Clear out all parts of the state in F that can safely be discarded
188 after the function has been parsed, but not compiled, to let
189 garbage collection reclaim the memory. */
191 void
192 free_after_parsing (struct function *f)
194 f->language = 0;
197 /* Clear out all parts of the state in F that can safely be discarded
198 after the function has been compiled, to let garbage collection
199 reclaim the memory. */
201 void
202 free_after_compilation (struct function *f)
204 prologue_insn_hash = NULL;
205 epilogue_insn_hash = NULL;
207 free (crtl->emit.regno_pointer_align);
209 memset (crtl, 0, sizeof (struct rtl_data));
210 f->eh = NULL;
211 f->machine = NULL;
212 f->cfg = NULL;
213 f->curr_properties &= ~PROP_cfg;
215 regno_reg_rtx = NULL;
218 /* Return size needed for stack frame based on slots so far allocated.
219 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
220 the caller may have to do that. */
222 poly_int64
223 get_frame_size (void)
225 if (FRAME_GROWS_DOWNWARD)
226 return -frame_offset;
227 else
228 return frame_offset;
231 /* Issue an error message and return TRUE if frame OFFSET overflows in
232 the signed target pointer arithmetics for function FUNC. Otherwise
233 return FALSE. */
235 bool
236 frame_offset_overflow (poly_int64 offset, tree func)
238 poly_uint64 size = FRAME_GROWS_DOWNWARD ? -offset : offset;
239 unsigned HOST_WIDE_INT limit
240 = ((HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (Pmode) - 1))
241 /* Leave room for the fixed part of the frame. */
242 - 64 * UNITS_PER_WORD);
244 if (!coeffs_in_range_p (size, 0U, limit))
246 unsigned HOST_WIDE_INT hwisize;
247 if (size.is_constant (&hwisize))
248 error_at (DECL_SOURCE_LOCATION (func),
249 "total size of local objects %wu exceeds maximum %wu",
250 hwisize, limit);
251 else
252 error_at (DECL_SOURCE_LOCATION (func),
253 "total size of local objects exceeds maximum %wu",
254 limit);
255 return true;
258 return false;
261 /* Return the minimum spill slot alignment for a register of mode MODE. */
263 unsigned int
264 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED)
266 return STACK_SLOT_ALIGNMENT (NULL_TREE, mode, GET_MODE_ALIGNMENT (mode));
269 /* Return stack slot alignment in bits for TYPE and MODE. */
271 static unsigned int
272 get_stack_local_alignment (tree type, machine_mode mode)
274 unsigned int alignment;
276 if (mode == BLKmode)
277 alignment = BIGGEST_ALIGNMENT;
278 else
279 alignment = GET_MODE_ALIGNMENT (mode);
281 /* Allow the frond-end to (possibly) increase the alignment of this
282 stack slot. */
283 if (! type)
284 type = lang_hooks.types.type_for_mode (mode, 0);
286 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
289 /* Determine whether it is possible to fit a stack slot of size SIZE and
290 alignment ALIGNMENT into an area in the stack frame that starts at
291 frame offset START and has a length of LENGTH. If so, store the frame
292 offset to be used for the stack slot in *POFFSET and return true;
293 return false otherwise. This function will extend the frame size when
294 given a start/length pair that lies at the end of the frame. */
296 static bool
297 try_fit_stack_local (poly_int64 start, poly_int64 length,
298 poly_int64 size, unsigned int alignment,
299 poly_int64_pod *poffset)
301 poly_int64 this_frame_offset;
302 int frame_off, frame_alignment, frame_phase;
304 /* Calculate how many bytes the start of local variables is off from
305 stack alignment. */
306 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
307 frame_off = targetm.starting_frame_offset () % frame_alignment;
308 frame_phase = frame_off ? frame_alignment - frame_off : 0;
310 /* Round the frame offset to the specified alignment. */
312 if (FRAME_GROWS_DOWNWARD)
313 this_frame_offset
314 = (aligned_lower_bound (start + length - size - frame_phase, alignment)
315 + frame_phase);
316 else
317 this_frame_offset
318 = aligned_upper_bound (start - frame_phase, alignment) + frame_phase;
320 /* See if it fits. If this space is at the edge of the frame,
321 consider extending the frame to make it fit. Our caller relies on
322 this when allocating a new slot. */
323 if (maybe_lt (this_frame_offset, start))
325 if (known_eq (frame_offset, start))
326 frame_offset = this_frame_offset;
327 else
328 return false;
330 else if (maybe_gt (this_frame_offset + size, start + length))
332 if (known_eq (frame_offset, start + length))
333 frame_offset = this_frame_offset + size;
334 else
335 return false;
338 *poffset = this_frame_offset;
339 return true;
342 /* Create a new frame_space structure describing free space in the stack
343 frame beginning at START and ending at END, and chain it into the
344 function's frame_space_list. */
346 static void
347 add_frame_space (poly_int64 start, poly_int64 end)
349 class frame_space *space = ggc_alloc<frame_space> ();
350 space->next = crtl->frame_space_list;
351 crtl->frame_space_list = space;
352 space->start = start;
353 space->length = end - start;
356 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
357 with machine mode MODE.
359 ALIGN controls the amount of alignment for the address of the slot:
360 0 means according to MODE,
361 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
362 -2 means use BITS_PER_UNIT,
363 positive specifies alignment boundary in bits.
365 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
366 alignment and ASLK_RECORD_PAD bit set if we should remember
367 extra space we allocated for alignment purposes. When we are
368 called from assign_stack_temp_for_type, it is not set so we don't
369 track the same stack slot in two independent lists.
371 We do not round to stack_boundary here. */
374 assign_stack_local_1 (machine_mode mode, poly_int64 size,
375 int align, int kind)
377 rtx x, addr;
378 poly_int64 bigend_correction = 0;
379 poly_int64 slot_offset = 0, old_frame_offset;
380 unsigned int alignment, alignment_in_bits;
382 if (align == 0)
384 alignment = get_stack_local_alignment (NULL, mode);
385 alignment /= BITS_PER_UNIT;
387 else if (align == -1)
389 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
390 size = aligned_upper_bound (size, alignment);
392 else if (align == -2)
393 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
394 else
395 alignment = align / BITS_PER_UNIT;
397 alignment_in_bits = alignment * BITS_PER_UNIT;
399 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
400 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
402 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
403 alignment = MAX_SUPPORTED_STACK_ALIGNMENT / BITS_PER_UNIT;
406 if (SUPPORTS_STACK_ALIGNMENT)
408 if (crtl->stack_alignment_estimated < alignment_in_bits)
410 if (!crtl->stack_realign_processed)
411 crtl->stack_alignment_estimated = alignment_in_bits;
412 else
414 /* If stack is realigned and stack alignment value
415 hasn't been finalized, it is OK not to increase
416 stack_alignment_estimated. The bigger alignment
417 requirement is recorded in stack_alignment_needed
418 below. */
419 gcc_assert (!crtl->stack_realign_finalized);
420 if (!crtl->stack_realign_needed)
422 /* It is OK to reduce the alignment as long as the
423 requested size is 0 or the estimated stack
424 alignment >= mode alignment. */
425 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
426 || known_eq (size, 0)
427 || (crtl->stack_alignment_estimated
428 >= GET_MODE_ALIGNMENT (mode)));
429 alignment_in_bits = crtl->stack_alignment_estimated;
430 alignment = alignment_in_bits / BITS_PER_UNIT;
436 if (crtl->stack_alignment_needed < alignment_in_bits)
437 crtl->stack_alignment_needed = alignment_in_bits;
438 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
439 crtl->max_used_stack_slot_alignment = alignment_in_bits;
441 if (mode != BLKmode || maybe_ne (size, 0))
443 if (kind & ASLK_RECORD_PAD)
445 class frame_space **psp;
447 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
449 class frame_space *space = *psp;
450 if (!try_fit_stack_local (space->start, space->length, size,
451 alignment, &slot_offset))
452 continue;
453 *psp = space->next;
454 if (known_gt (slot_offset, space->start))
455 add_frame_space (space->start, slot_offset);
456 if (known_lt (slot_offset + size, space->start + space->length))
457 add_frame_space (slot_offset + size,
458 space->start + space->length);
459 goto found_space;
463 else if (!STACK_ALIGNMENT_NEEDED)
465 slot_offset = frame_offset;
466 goto found_space;
469 old_frame_offset = frame_offset;
471 if (FRAME_GROWS_DOWNWARD)
473 frame_offset -= size;
474 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
476 if (kind & ASLK_RECORD_PAD)
478 if (known_gt (slot_offset, frame_offset))
479 add_frame_space (frame_offset, slot_offset);
480 if (known_lt (slot_offset + size, old_frame_offset))
481 add_frame_space (slot_offset + size, old_frame_offset);
484 else
486 frame_offset += size;
487 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
489 if (kind & ASLK_RECORD_PAD)
491 if (known_gt (slot_offset, old_frame_offset))
492 add_frame_space (old_frame_offset, slot_offset);
493 if (known_lt (slot_offset + size, frame_offset))
494 add_frame_space (slot_offset + size, frame_offset);
498 found_space:
499 /* On a big-endian machine, if we are allocating more space than we will use,
500 use the least significant bytes of those that are allocated. */
501 if (mode != BLKmode)
503 /* The slot size can sometimes be smaller than the mode size;
504 e.g. the rs6000 port allocates slots with a vector mode
505 that have the size of only one element. However, the slot
506 size must always be ordered wrt to the mode size, in the
507 same way as for a subreg. */
508 gcc_checking_assert (ordered_p (GET_MODE_SIZE (mode), size));
509 if (BYTES_BIG_ENDIAN && maybe_lt (GET_MODE_SIZE (mode), size))
510 bigend_correction = size - GET_MODE_SIZE (mode);
513 /* If we have already instantiated virtual registers, return the actual
514 address relative to the frame pointer. */
515 if (virtuals_instantiated)
516 addr = plus_constant (Pmode, frame_pointer_rtx,
517 trunc_int_for_mode
518 (slot_offset + bigend_correction
519 + targetm.starting_frame_offset (), Pmode));
520 else
521 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
522 trunc_int_for_mode
523 (slot_offset + bigend_correction,
524 Pmode));
526 x = gen_rtx_MEM (mode, addr);
527 set_mem_align (x, alignment_in_bits);
528 MEM_NOTRAP_P (x) = 1;
530 vec_safe_push (stack_slot_list, x);
532 if (frame_offset_overflow (frame_offset, current_function_decl))
533 frame_offset = 0;
535 return x;
538 /* Wrap up assign_stack_local_1 with last parameter as false. */
541 assign_stack_local (machine_mode mode, poly_int64 size, int align)
543 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
546 /* In order to evaluate some expressions, such as function calls returning
547 structures in memory, we need to temporarily allocate stack locations.
548 We record each allocated temporary in the following structure.
550 Associated with each temporary slot is a nesting level. When we pop up
551 one level, all temporaries associated with the previous level are freed.
552 Normally, all temporaries are freed after the execution of the statement
553 in which they were created. However, if we are inside a ({...}) grouping,
554 the result may be in a temporary and hence must be preserved. If the
555 result could be in a temporary, we preserve it if we can determine which
556 one it is in. If we cannot determine which temporary may contain the
557 result, all temporaries are preserved. A temporary is preserved by
558 pretending it was allocated at the previous nesting level. */
560 class GTY(()) temp_slot {
561 public:
562 /* Points to next temporary slot. */
563 class temp_slot *next;
564 /* Points to previous temporary slot. */
565 class temp_slot *prev;
566 /* The rtx to used to reference the slot. */
567 rtx slot;
568 /* The size, in units, of the slot. */
569 poly_int64 size;
570 /* The type of the object in the slot, or zero if it doesn't correspond
571 to a type. We use this to determine whether a slot can be reused.
572 It can be reused if objects of the type of the new slot will always
573 conflict with objects of the type of the old slot. */
574 tree type;
575 /* The alignment (in bits) of the slot. */
576 unsigned int align;
577 /* Nonzero if this temporary is currently in use. */
578 char in_use;
579 /* Nesting level at which this slot is being used. */
580 int level;
581 /* The offset of the slot from the frame_pointer, including extra space
582 for alignment. This info is for combine_temp_slots. */
583 poly_int64 base_offset;
584 /* The size of the slot, including extra space for alignment. This
585 info is for combine_temp_slots. */
586 poly_int64 full_size;
589 /* Entry for the below hash table. */
590 struct GTY((for_user)) temp_slot_address_entry {
591 hashval_t hash;
592 rtx address;
593 class temp_slot *temp_slot;
596 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
598 static hashval_t hash (temp_slot_address_entry *);
599 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
602 /* A table of addresses that represent a stack slot. The table is a mapping
603 from address RTXen to a temp slot. */
604 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
605 static size_t n_temp_slots_in_use;
607 /* Removes temporary slot TEMP from LIST. */
609 static void
610 cut_slot_from_list (class temp_slot *temp, class temp_slot **list)
612 if (temp->next)
613 temp->next->prev = temp->prev;
614 if (temp->prev)
615 temp->prev->next = temp->next;
616 else
617 *list = temp->next;
619 temp->prev = temp->next = NULL;
622 /* Inserts temporary slot TEMP to LIST. */
624 static void
625 insert_slot_to_list (class temp_slot *temp, class temp_slot **list)
627 temp->next = *list;
628 if (*list)
629 (*list)->prev = temp;
630 temp->prev = NULL;
631 *list = temp;
634 /* Returns the list of used temp slots at LEVEL. */
636 static class temp_slot **
637 temp_slots_at_level (int level)
639 if (level >= (int) vec_safe_length (used_temp_slots))
640 vec_safe_grow_cleared (used_temp_slots, level + 1);
642 return &(*used_temp_slots)[level];
645 /* Returns the maximal temporary slot level. */
647 static int
648 max_slot_level (void)
650 if (!used_temp_slots)
651 return -1;
653 return used_temp_slots->length () - 1;
656 /* Moves temporary slot TEMP to LEVEL. */
658 static void
659 move_slot_to_level (class temp_slot *temp, int level)
661 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
662 insert_slot_to_list (temp, temp_slots_at_level (level));
663 temp->level = level;
666 /* Make temporary slot TEMP available. */
668 static void
669 make_slot_available (class temp_slot *temp)
671 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
672 insert_slot_to_list (temp, &avail_temp_slots);
673 temp->in_use = 0;
674 temp->level = -1;
675 n_temp_slots_in_use--;
678 /* Compute the hash value for an address -> temp slot mapping.
679 The value is cached on the mapping entry. */
680 static hashval_t
681 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
683 int do_not_record = 0;
684 return hash_rtx (t->address, GET_MODE (t->address),
685 &do_not_record, NULL, false);
688 /* Return the hash value for an address -> temp slot mapping. */
689 hashval_t
690 temp_address_hasher::hash (temp_slot_address_entry *t)
692 return t->hash;
695 /* Compare two address -> temp slot mapping entries. */
696 bool
697 temp_address_hasher::equal (temp_slot_address_entry *t1,
698 temp_slot_address_entry *t2)
700 return exp_equiv_p (t1->address, t2->address, 0, true);
703 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
704 static void
705 insert_temp_slot_address (rtx address, class temp_slot *temp_slot)
707 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
708 t->address = copy_rtx (address);
709 t->temp_slot = temp_slot;
710 t->hash = temp_slot_address_compute_hash (t);
711 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
714 /* Remove an address -> temp slot mapping entry if the temp slot is
715 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
717 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
719 const struct temp_slot_address_entry *t = *slot;
720 if (! t->temp_slot->in_use)
721 temp_slot_address_table->clear_slot (slot);
722 return 1;
725 /* Remove all mappings of addresses to unused temp slots. */
726 static void
727 remove_unused_temp_slot_addresses (void)
729 /* Use quicker clearing if there aren't any active temp slots. */
730 if (n_temp_slots_in_use)
731 temp_slot_address_table->traverse
732 <void *, remove_unused_temp_slot_addresses_1> (NULL);
733 else
734 temp_slot_address_table->empty ();
737 /* Find the temp slot corresponding to the object at address X. */
739 static class temp_slot *
740 find_temp_slot_from_address (rtx x)
742 class temp_slot *p;
743 struct temp_slot_address_entry tmp, *t;
745 /* First try the easy way:
746 See if X exists in the address -> temp slot mapping. */
747 tmp.address = x;
748 tmp.temp_slot = NULL;
749 tmp.hash = temp_slot_address_compute_hash (&tmp);
750 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
751 if (t)
752 return t->temp_slot;
754 /* If we have a sum involving a register, see if it points to a temp
755 slot. */
756 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
757 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
758 return p;
759 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
760 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
761 return p;
763 /* Last resort: Address is a virtual stack var address. */
764 poly_int64 offset;
765 if (strip_offset (x, &offset) == virtual_stack_vars_rtx)
767 int i;
768 for (i = max_slot_level (); i >= 0; i--)
769 for (p = *temp_slots_at_level (i); p; p = p->next)
770 if (known_in_range_p (offset, p->base_offset, p->full_size))
771 return p;
774 return NULL;
777 /* Allocate a temporary stack slot and record it for possible later
778 reuse.
780 MODE is the machine mode to be given to the returned rtx.
782 SIZE is the size in units of the space required. We do no rounding here
783 since assign_stack_local will do any required rounding.
785 TYPE is the type that will be used for the stack slot. */
788 assign_stack_temp_for_type (machine_mode mode, poly_int64 size, tree type)
790 unsigned int align;
791 class temp_slot *p, *best_p = 0, *selected = NULL, **pp;
792 rtx slot;
794 gcc_assert (known_size_p (size));
796 align = get_stack_local_alignment (type, mode);
798 /* Try to find an available, already-allocated temporary of the proper
799 mode which meets the size and alignment requirements. Choose the
800 smallest one with the closest alignment.
802 If assign_stack_temp is called outside of the tree->rtl expansion,
803 we cannot reuse the stack slots (that may still refer to
804 VIRTUAL_STACK_VARS_REGNUM). */
805 if (!virtuals_instantiated)
807 for (p = avail_temp_slots; p; p = p->next)
809 if (p->align >= align
810 && known_ge (p->size, size)
811 && GET_MODE (p->slot) == mode
812 && objects_must_conflict_p (p->type, type)
813 && (best_p == 0
814 || (known_eq (best_p->size, p->size)
815 ? best_p->align > p->align
816 : known_ge (best_p->size, p->size))))
818 if (p->align == align && known_eq (p->size, size))
820 selected = p;
821 cut_slot_from_list (selected, &avail_temp_slots);
822 best_p = 0;
823 break;
825 best_p = p;
830 /* Make our best, if any, the one to use. */
831 if (best_p)
833 selected = best_p;
834 cut_slot_from_list (selected, &avail_temp_slots);
836 /* If there are enough aligned bytes left over, make them into a new
837 temp_slot so that the extra bytes don't get wasted. Do this only
838 for BLKmode slots, so that we can be sure of the alignment. */
839 if (GET_MODE (best_p->slot) == BLKmode)
841 int alignment = best_p->align / BITS_PER_UNIT;
842 poly_int64 rounded_size = aligned_upper_bound (size, alignment);
844 if (known_ge (best_p->size - rounded_size, alignment))
846 p = ggc_alloc<temp_slot> ();
847 p->in_use = 0;
848 p->size = best_p->size - rounded_size;
849 p->base_offset = best_p->base_offset + rounded_size;
850 p->full_size = best_p->full_size - rounded_size;
851 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
852 p->align = best_p->align;
853 p->type = best_p->type;
854 insert_slot_to_list (p, &avail_temp_slots);
856 vec_safe_push (stack_slot_list, p->slot);
858 best_p->size = rounded_size;
859 best_p->full_size = rounded_size;
864 /* If we still didn't find one, make a new temporary. */
865 if (selected == 0)
867 poly_int64 frame_offset_old = frame_offset;
869 p = ggc_alloc<temp_slot> ();
871 /* We are passing an explicit alignment request to assign_stack_local.
872 One side effect of that is assign_stack_local will not round SIZE
873 to ensure the frame offset remains suitably aligned.
875 So for requests which depended on the rounding of SIZE, we go ahead
876 and round it now. We also make sure ALIGNMENT is at least
877 BIGGEST_ALIGNMENT. */
878 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
879 p->slot = assign_stack_local_1 (mode,
880 (mode == BLKmode
881 ? aligned_upper_bound (size,
882 (int) align
883 / BITS_PER_UNIT)
884 : size),
885 align, 0);
887 p->align = align;
889 /* The following slot size computation is necessary because we don't
890 know the actual size of the temporary slot until assign_stack_local
891 has performed all the frame alignment and size rounding for the
892 requested temporary. Note that extra space added for alignment
893 can be either above or below this stack slot depending on which
894 way the frame grows. We include the extra space if and only if it
895 is above this slot. */
896 if (FRAME_GROWS_DOWNWARD)
897 p->size = frame_offset_old - frame_offset;
898 else
899 p->size = size;
901 /* Now define the fields used by combine_temp_slots. */
902 if (FRAME_GROWS_DOWNWARD)
904 p->base_offset = frame_offset;
905 p->full_size = frame_offset_old - frame_offset;
907 else
909 p->base_offset = frame_offset_old;
910 p->full_size = frame_offset - frame_offset_old;
913 selected = p;
916 p = selected;
917 p->in_use = 1;
918 p->type = type;
919 p->level = temp_slot_level;
920 n_temp_slots_in_use++;
922 pp = temp_slots_at_level (p->level);
923 insert_slot_to_list (p, pp);
924 insert_temp_slot_address (XEXP (p->slot, 0), p);
926 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
927 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
928 vec_safe_push (stack_slot_list, slot);
930 /* If we know the alias set for the memory that will be used, use
931 it. If there's no TYPE, then we don't know anything about the
932 alias set for the memory. */
933 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
934 set_mem_align (slot, align);
936 /* If a type is specified, set the relevant flags. */
937 if (type != 0)
938 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
939 MEM_NOTRAP_P (slot) = 1;
941 return slot;
944 /* Allocate a temporary stack slot and record it for possible later
945 reuse. First two arguments are same as in preceding function. */
948 assign_stack_temp (machine_mode mode, poly_int64 size)
950 return assign_stack_temp_for_type (mode, size, NULL_TREE);
953 /* Assign a temporary.
954 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
955 and so that should be used in error messages. In either case, we
956 allocate of the given type.
957 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
958 it is 0 if a register is OK.
959 DONT_PROMOTE is 1 if we should not promote values in register
960 to wider modes. */
963 assign_temp (tree type_or_decl, int memory_required,
964 int dont_promote ATTRIBUTE_UNUSED)
966 tree type, decl;
967 machine_mode mode;
968 #ifdef PROMOTE_MODE
969 int unsignedp;
970 #endif
972 if (DECL_P (type_or_decl))
973 decl = type_or_decl, type = TREE_TYPE (decl);
974 else
975 decl = NULL, type = type_or_decl;
977 mode = TYPE_MODE (type);
978 #ifdef PROMOTE_MODE
979 unsignedp = TYPE_UNSIGNED (type);
980 #endif
982 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
983 end. See also create_tmp_var for the gimplification-time check. */
984 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
986 if (mode == BLKmode || memory_required)
988 poly_int64 size;
989 rtx tmp;
991 /* Unfortunately, we don't yet know how to allocate variable-sized
992 temporaries. However, sometimes we can find a fixed upper limit on
993 the size, so try that instead. */
994 if (!poly_int_tree_p (TYPE_SIZE_UNIT (type), &size))
995 size = max_int_size_in_bytes (type);
997 /* Zero sized arrays are a GNU C extension. Set size to 1 to avoid
998 problems with allocating the stack space. */
999 if (known_eq (size, 0))
1000 size = 1;
1002 /* The size of the temporary may be too large to fit into an integer. */
1003 /* ??? Not sure this should happen except for user silliness, so limit
1004 this to things that aren't compiler-generated temporaries. The
1005 rest of the time we'll die in assign_stack_temp_for_type. */
1006 if (decl
1007 && !known_size_p (size)
1008 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
1010 error ("size of variable %q+D is too large", decl);
1011 size = 1;
1014 tmp = assign_stack_temp_for_type (mode, size, type);
1015 return tmp;
1018 #ifdef PROMOTE_MODE
1019 if (! dont_promote)
1020 mode = promote_mode (type, mode, &unsignedp);
1021 #endif
1023 return gen_reg_rtx (mode);
1026 /* Combine temporary stack slots which are adjacent on the stack.
1028 This allows for better use of already allocated stack space. This is only
1029 done for BLKmode slots because we can be sure that we won't have alignment
1030 problems in this case. */
1032 static void
1033 combine_temp_slots (void)
1035 class temp_slot *p, *q, *next, *next_q;
1036 int num_slots;
1038 /* We can't combine slots, because the information about which slot
1039 is in which alias set will be lost. */
1040 if (flag_strict_aliasing)
1041 return;
1043 /* If there are a lot of temp slots, don't do anything unless
1044 high levels of optimization. */
1045 if (! flag_expensive_optimizations)
1046 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1047 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1048 return;
1050 for (p = avail_temp_slots; p; p = next)
1052 int delete_p = 0;
1054 next = p->next;
1056 if (GET_MODE (p->slot) != BLKmode)
1057 continue;
1059 for (q = p->next; q; q = next_q)
1061 int delete_q = 0;
1063 next_q = q->next;
1065 if (GET_MODE (q->slot) != BLKmode)
1066 continue;
1068 if (known_eq (p->base_offset + p->full_size, q->base_offset))
1070 /* Q comes after P; combine Q into P. */
1071 p->size += q->size;
1072 p->full_size += q->full_size;
1073 delete_q = 1;
1075 else if (known_eq (q->base_offset + q->full_size, p->base_offset))
1077 /* P comes after Q; combine P into Q. */
1078 q->size += p->size;
1079 q->full_size += p->full_size;
1080 delete_p = 1;
1081 break;
1083 if (delete_q)
1084 cut_slot_from_list (q, &avail_temp_slots);
1087 /* Either delete P or advance past it. */
1088 if (delete_p)
1089 cut_slot_from_list (p, &avail_temp_slots);
1093 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1094 slot that previously was known by OLD_RTX. */
1096 void
1097 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1099 class temp_slot *p;
1101 if (rtx_equal_p (old_rtx, new_rtx))
1102 return;
1104 p = find_temp_slot_from_address (old_rtx);
1106 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1107 NEW_RTX is a register, see if one operand of the PLUS is a
1108 temporary location. If so, NEW_RTX points into it. Otherwise,
1109 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1110 in common between them. If so, try a recursive call on those
1111 values. */
1112 if (p == 0)
1114 if (GET_CODE (old_rtx) != PLUS)
1115 return;
1117 if (REG_P (new_rtx))
1119 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1120 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1121 return;
1123 else if (GET_CODE (new_rtx) != PLUS)
1124 return;
1126 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1127 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1128 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1129 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1130 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1131 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1132 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1133 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1135 return;
1138 /* Otherwise add an alias for the temp's address. */
1139 insert_temp_slot_address (new_rtx, p);
1142 /* If X could be a reference to a temporary slot, mark that slot as
1143 belonging to the to one level higher than the current level. If X
1144 matched one of our slots, just mark that one. Otherwise, we can't
1145 easily predict which it is, so upgrade all of them.
1147 This is called when an ({...}) construct occurs and a statement
1148 returns a value in memory. */
1150 void
1151 preserve_temp_slots (rtx x)
1153 class temp_slot *p = 0, *next;
1155 if (x == 0)
1156 return;
1158 /* If X is a register that is being used as a pointer, see if we have
1159 a temporary slot we know it points to. */
1160 if (REG_P (x) && REG_POINTER (x))
1161 p = find_temp_slot_from_address (x);
1163 /* If X is not in memory or is at a constant address, it cannot be in
1164 a temporary slot. */
1165 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1166 return;
1168 /* First see if we can find a match. */
1169 if (p == 0)
1170 p = find_temp_slot_from_address (XEXP (x, 0));
1172 if (p != 0)
1174 if (p->level == temp_slot_level)
1175 move_slot_to_level (p, temp_slot_level - 1);
1176 return;
1179 /* Otherwise, preserve all non-kept slots at this level. */
1180 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1182 next = p->next;
1183 move_slot_to_level (p, temp_slot_level - 1);
1187 /* Free all temporaries used so far. This is normally called at the
1188 end of generating code for a statement. */
1190 void
1191 free_temp_slots (void)
1193 class temp_slot *p, *next;
1194 bool some_available = false;
1196 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1198 next = p->next;
1199 make_slot_available (p);
1200 some_available = true;
1203 if (some_available)
1205 remove_unused_temp_slot_addresses ();
1206 combine_temp_slots ();
1210 /* Push deeper into the nesting level for stack temporaries. */
1212 void
1213 push_temp_slots (void)
1215 temp_slot_level++;
1218 /* Pop a temporary nesting level. All slots in use in the current level
1219 are freed. */
1221 void
1222 pop_temp_slots (void)
1224 free_temp_slots ();
1225 temp_slot_level--;
1228 /* Initialize temporary slots. */
1230 void
1231 init_temp_slots (void)
1233 /* We have not allocated any temporaries yet. */
1234 avail_temp_slots = 0;
1235 vec_alloc (used_temp_slots, 0);
1236 temp_slot_level = 0;
1237 n_temp_slots_in_use = 0;
1239 /* Set up the table to map addresses to temp slots. */
1240 if (! temp_slot_address_table)
1241 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1242 else
1243 temp_slot_address_table->empty ();
1246 /* Functions and data structures to keep track of the values hard regs
1247 had at the start of the function. */
1249 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1250 and has_hard_reg_initial_val.. */
1251 struct GTY(()) initial_value_pair {
1252 rtx hard_reg;
1253 rtx pseudo;
1255 /* ??? This could be a VEC but there is currently no way to define an
1256 opaque VEC type. This could be worked around by defining struct
1257 initial_value_pair in function.h. */
1258 struct GTY(()) initial_value_struct {
1259 int num_entries;
1260 int max_entries;
1261 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1264 /* If a pseudo represents an initial hard reg (or expression), return
1265 it, else return NULL_RTX. */
1268 get_hard_reg_initial_reg (rtx reg)
1270 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1271 int i;
1273 if (ivs == 0)
1274 return NULL_RTX;
1276 for (i = 0; i < ivs->num_entries; i++)
1277 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1278 return ivs->entries[i].hard_reg;
1280 return NULL_RTX;
1283 /* Make sure that there's a pseudo register of mode MODE that stores the
1284 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1287 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1289 struct initial_value_struct *ivs;
1290 rtx rv;
1292 rv = has_hard_reg_initial_val (mode, regno);
1293 if (rv)
1294 return rv;
1296 ivs = crtl->hard_reg_initial_vals;
1297 if (ivs == 0)
1299 ivs = ggc_alloc<initial_value_struct> ();
1300 ivs->num_entries = 0;
1301 ivs->max_entries = 5;
1302 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1303 crtl->hard_reg_initial_vals = ivs;
1306 if (ivs->num_entries >= ivs->max_entries)
1308 ivs->max_entries += 5;
1309 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1310 ivs->max_entries);
1313 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1314 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1316 return ivs->entries[ivs->num_entries++].pseudo;
1319 /* See if get_hard_reg_initial_val has been used to create a pseudo
1320 for the initial value of hard register REGNO in mode MODE. Return
1321 the associated pseudo if so, otherwise return NULL. */
1324 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1326 struct initial_value_struct *ivs;
1327 int i;
1329 ivs = crtl->hard_reg_initial_vals;
1330 if (ivs != 0)
1331 for (i = 0; i < ivs->num_entries; i++)
1332 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1333 && REGNO (ivs->entries[i].hard_reg) == regno)
1334 return ivs->entries[i].pseudo;
1336 return NULL_RTX;
1339 unsigned int
1340 emit_initial_value_sets (void)
1342 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1343 int i;
1344 rtx_insn *seq;
1346 if (ivs == 0)
1347 return 0;
1349 start_sequence ();
1350 for (i = 0; i < ivs->num_entries; i++)
1351 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1352 seq = get_insns ();
1353 end_sequence ();
1355 emit_insn_at_entry (seq);
1356 return 0;
1359 /* Return the hardreg-pseudoreg initial values pair entry I and
1360 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1361 bool
1362 initial_value_entry (int i, rtx *hreg, rtx *preg)
1364 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1365 if (!ivs || i >= ivs->num_entries)
1366 return false;
1368 *hreg = ivs->entries[i].hard_reg;
1369 *preg = ivs->entries[i].pseudo;
1370 return true;
1373 /* These routines are responsible for converting virtual register references
1374 to the actual hard register references once RTL generation is complete.
1376 The following four variables are used for communication between the
1377 routines. They contain the offsets of the virtual registers from their
1378 respective hard registers. */
1380 static poly_int64 in_arg_offset;
1381 static poly_int64 var_offset;
1382 static poly_int64 dynamic_offset;
1383 static poly_int64 out_arg_offset;
1384 static poly_int64 cfa_offset;
1386 /* In most machines, the stack pointer register is equivalent to the bottom
1387 of the stack. */
1389 #ifndef STACK_POINTER_OFFSET
1390 #define STACK_POINTER_OFFSET 0
1391 #endif
1393 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1394 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1395 #endif
1397 /* If not defined, pick an appropriate default for the offset of dynamically
1398 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1399 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1401 #ifndef STACK_DYNAMIC_OFFSET
1403 /* The bottom of the stack points to the actual arguments. If
1404 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1405 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1406 stack space for register parameters is not pushed by the caller, but
1407 rather part of the fixed stack areas and hence not included in
1408 `crtl->outgoing_args_size'. Nevertheless, we must allow
1409 for it when allocating stack dynamic objects. */
1411 #ifdef INCOMING_REG_PARM_STACK_SPACE
1412 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1413 ((ACCUMULATE_OUTGOING_ARGS \
1414 ? (crtl->outgoing_args_size \
1415 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1416 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1417 : 0) + (STACK_POINTER_OFFSET))
1418 #else
1419 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1420 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : poly_int64 (0)) \
1421 + (STACK_POINTER_OFFSET))
1422 #endif
1423 #endif
1426 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1427 is a virtual register, return the equivalent hard register and set the
1428 offset indirectly through the pointer. Otherwise, return 0. */
1430 static rtx
1431 instantiate_new_reg (rtx x, poly_int64_pod *poffset)
1433 rtx new_rtx;
1434 poly_int64 offset;
1436 if (x == virtual_incoming_args_rtx)
1438 if (stack_realign_drap)
1440 /* Replace virtual_incoming_args_rtx with internal arg
1441 pointer if DRAP is used to realign stack. */
1442 new_rtx = crtl->args.internal_arg_pointer;
1443 offset = 0;
1445 else
1446 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1448 else if (x == virtual_stack_vars_rtx)
1449 new_rtx = frame_pointer_rtx, offset = var_offset;
1450 else if (x == virtual_stack_dynamic_rtx)
1451 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1452 else if (x == virtual_outgoing_args_rtx)
1453 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1454 else if (x == virtual_cfa_rtx)
1456 #ifdef FRAME_POINTER_CFA_OFFSET
1457 new_rtx = frame_pointer_rtx;
1458 #else
1459 new_rtx = arg_pointer_rtx;
1460 #endif
1461 offset = cfa_offset;
1463 else if (x == virtual_preferred_stack_boundary_rtx)
1465 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1466 offset = 0;
1468 else
1469 return NULL_RTX;
1471 *poffset = offset;
1472 return new_rtx;
1475 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1476 registers present inside of *LOC. The expression is simplified,
1477 as much as possible, but is not to be considered "valid" in any sense
1478 implied by the target. Return true if any change is made. */
1480 static bool
1481 instantiate_virtual_regs_in_rtx (rtx *loc)
1483 if (!*loc)
1484 return false;
1485 bool changed = false;
1486 subrtx_ptr_iterator::array_type array;
1487 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1489 rtx *loc = *iter;
1490 if (rtx x = *loc)
1492 rtx new_rtx;
1493 poly_int64 offset;
1494 switch (GET_CODE (x))
1496 case REG:
1497 new_rtx = instantiate_new_reg (x, &offset);
1498 if (new_rtx)
1500 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1501 changed = true;
1503 iter.skip_subrtxes ();
1504 break;
1506 case PLUS:
1507 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1508 if (new_rtx)
1510 XEXP (x, 0) = new_rtx;
1511 *loc = plus_constant (GET_MODE (x), x, offset, true);
1512 changed = true;
1513 iter.skip_subrtxes ();
1514 break;
1517 /* FIXME -- from old code */
1518 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1519 we can commute the PLUS and SUBREG because pointers into the
1520 frame are well-behaved. */
1521 break;
1523 default:
1524 break;
1528 return changed;
1531 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1532 matches the predicate for insn CODE operand OPERAND. */
1534 static int
1535 safe_insn_predicate (int code, int operand, rtx x)
1537 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1540 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1541 registers present inside of insn. The result will be a valid insn. */
1543 static void
1544 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1546 poly_int64 offset;
1547 int insn_code, i;
1548 bool any_change = false;
1549 rtx set, new_rtx, x;
1550 rtx_insn *seq;
1552 /* There are some special cases to be handled first. */
1553 set = single_set (insn);
1554 if (set)
1556 /* We're allowed to assign to a virtual register. This is interpreted
1557 to mean that the underlying register gets assigned the inverse
1558 transformation. This is used, for example, in the handling of
1559 non-local gotos. */
1560 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1561 if (new_rtx)
1563 start_sequence ();
1565 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1566 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1567 gen_int_mode (-offset, GET_MODE (new_rtx)));
1568 x = force_operand (x, new_rtx);
1569 if (x != new_rtx)
1570 emit_move_insn (new_rtx, x);
1572 seq = get_insns ();
1573 end_sequence ();
1575 emit_insn_before (seq, insn);
1576 delete_insn (insn);
1577 return;
1580 /* Handle a straight copy from a virtual register by generating a
1581 new add insn. The difference between this and falling through
1582 to the generic case is avoiding a new pseudo and eliminating a
1583 move insn in the initial rtl stream. */
1584 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1585 if (new_rtx
1586 && maybe_ne (offset, 0)
1587 && REG_P (SET_DEST (set))
1588 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1590 start_sequence ();
1592 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1593 gen_int_mode (offset,
1594 GET_MODE (SET_DEST (set))),
1595 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1596 if (x != SET_DEST (set))
1597 emit_move_insn (SET_DEST (set), x);
1599 seq = get_insns ();
1600 end_sequence ();
1602 emit_insn_before (seq, insn);
1603 delete_insn (insn);
1604 return;
1607 extract_insn (insn);
1608 insn_code = INSN_CODE (insn);
1610 /* Handle a plus involving a virtual register by determining if the
1611 operands remain valid if they're modified in place. */
1612 poly_int64 delta;
1613 if (GET_CODE (SET_SRC (set)) == PLUS
1614 && recog_data.n_operands >= 3
1615 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1616 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1617 && poly_int_rtx_p (recog_data.operand[2], &delta)
1618 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1620 offset += delta;
1622 /* If the sum is zero, then replace with a plain move. */
1623 if (known_eq (offset, 0)
1624 && REG_P (SET_DEST (set))
1625 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1627 start_sequence ();
1628 emit_move_insn (SET_DEST (set), new_rtx);
1629 seq = get_insns ();
1630 end_sequence ();
1632 emit_insn_before (seq, insn);
1633 delete_insn (insn);
1634 return;
1637 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1639 /* Using validate_change and apply_change_group here leaves
1640 recog_data in an invalid state. Since we know exactly what
1641 we want to check, do those two by hand. */
1642 if (safe_insn_predicate (insn_code, 1, new_rtx)
1643 && safe_insn_predicate (insn_code, 2, x))
1645 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1646 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1647 any_change = true;
1649 /* Fall through into the regular operand fixup loop in
1650 order to take care of operands other than 1 and 2. */
1654 else
1656 extract_insn (insn);
1657 insn_code = INSN_CODE (insn);
1660 /* In the general case, we expect virtual registers to appear only in
1661 operands, and then only as either bare registers or inside memories. */
1662 for (i = 0; i < recog_data.n_operands; ++i)
1664 x = recog_data.operand[i];
1665 switch (GET_CODE (x))
1667 case MEM:
1669 rtx addr = XEXP (x, 0);
1671 if (!instantiate_virtual_regs_in_rtx (&addr))
1672 continue;
1674 start_sequence ();
1675 x = replace_equiv_address (x, addr, true);
1676 /* It may happen that the address with the virtual reg
1677 was valid (e.g. based on the virtual stack reg, which might
1678 be acceptable to the predicates with all offsets), whereas
1679 the address now isn't anymore, for instance when the address
1680 is still offsetted, but the base reg isn't virtual-stack-reg
1681 anymore. Below we would do a force_reg on the whole operand,
1682 but this insn might actually only accept memory. Hence,
1683 before doing that last resort, try to reload the address into
1684 a register, so this operand stays a MEM. */
1685 if (!safe_insn_predicate (insn_code, i, x))
1687 addr = force_reg (GET_MODE (addr), addr);
1688 x = replace_equiv_address (x, addr, true);
1690 seq = get_insns ();
1691 end_sequence ();
1692 if (seq)
1693 emit_insn_before (seq, insn);
1695 break;
1697 case REG:
1698 new_rtx = instantiate_new_reg (x, &offset);
1699 if (new_rtx == NULL)
1700 continue;
1701 if (known_eq (offset, 0))
1702 x = new_rtx;
1703 else
1705 start_sequence ();
1707 /* Careful, special mode predicates may have stuff in
1708 insn_data[insn_code].operand[i].mode that isn't useful
1709 to us for computing a new value. */
1710 /* ??? Recognize address_operand and/or "p" constraints
1711 to see if (plus new offset) is a valid before we put
1712 this through expand_simple_binop. */
1713 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1714 gen_int_mode (offset, GET_MODE (x)),
1715 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1716 seq = get_insns ();
1717 end_sequence ();
1718 emit_insn_before (seq, insn);
1720 break;
1722 case SUBREG:
1723 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1724 if (new_rtx == NULL)
1725 continue;
1726 if (maybe_ne (offset, 0))
1728 start_sequence ();
1729 new_rtx = expand_simple_binop
1730 (GET_MODE (new_rtx), PLUS, new_rtx,
1731 gen_int_mode (offset, GET_MODE (new_rtx)),
1732 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1733 seq = get_insns ();
1734 end_sequence ();
1735 emit_insn_before (seq, insn);
1737 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1738 GET_MODE (new_rtx), SUBREG_BYTE (x));
1739 gcc_assert (x);
1740 break;
1742 default:
1743 continue;
1746 /* At this point, X contains the new value for the operand.
1747 Validate the new value vs the insn predicate. Note that
1748 asm insns will have insn_code -1 here. */
1749 if (!safe_insn_predicate (insn_code, i, x))
1751 start_sequence ();
1752 if (REG_P (x))
1754 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1755 x = copy_to_reg (x);
1757 else
1758 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1759 seq = get_insns ();
1760 end_sequence ();
1761 if (seq)
1762 emit_insn_before (seq, insn);
1765 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1766 any_change = true;
1769 if (any_change)
1771 /* Propagate operand changes into the duplicates. */
1772 for (i = 0; i < recog_data.n_dups; ++i)
1773 *recog_data.dup_loc[i]
1774 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1776 /* Force re-recognition of the instruction for validation. */
1777 INSN_CODE (insn) = -1;
1780 if (asm_noperands (PATTERN (insn)) >= 0)
1782 if (!check_asm_operands (PATTERN (insn)))
1784 error_for_asm (insn, "impossible constraint in %<asm%>");
1785 /* For asm goto, instead of fixing up all the edges
1786 just clear the template and clear input operands
1787 (asm goto doesn't have any output operands). */
1788 if (JUMP_P (insn))
1790 rtx asm_op = extract_asm_operands (PATTERN (insn));
1791 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1792 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1793 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1795 else
1796 delete_insn (insn);
1799 else
1801 if (recog_memoized (insn) < 0)
1802 fatal_insn_not_found (insn);
1806 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1807 do any instantiation required. */
1809 void
1810 instantiate_decl_rtl (rtx x)
1812 rtx addr;
1814 if (x == 0)
1815 return;
1817 /* If this is a CONCAT, recurse for the pieces. */
1818 if (GET_CODE (x) == CONCAT)
1820 instantiate_decl_rtl (XEXP (x, 0));
1821 instantiate_decl_rtl (XEXP (x, 1));
1822 return;
1825 /* If this is not a MEM, no need to do anything. Similarly if the
1826 address is a constant or a register that is not a virtual register. */
1827 if (!MEM_P (x))
1828 return;
1830 addr = XEXP (x, 0);
1831 if (CONSTANT_P (addr)
1832 || (REG_P (addr)
1833 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1834 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1835 return;
1837 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1840 /* Helper for instantiate_decls called via walk_tree: Process all decls
1841 in the given DECL_VALUE_EXPR. */
1843 static tree
1844 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1846 tree t = *tp;
1847 if (! EXPR_P (t))
1849 *walk_subtrees = 0;
1850 if (DECL_P (t))
1852 if (DECL_RTL_SET_P (t))
1853 instantiate_decl_rtl (DECL_RTL (t));
1854 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1855 && DECL_INCOMING_RTL (t))
1856 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1857 if ((VAR_P (t) || TREE_CODE (t) == RESULT_DECL)
1858 && DECL_HAS_VALUE_EXPR_P (t))
1860 tree v = DECL_VALUE_EXPR (t);
1861 walk_tree (&v, instantiate_expr, NULL, NULL);
1865 return NULL;
1868 /* Subroutine of instantiate_decls: Process all decls in the given
1869 BLOCK node and all its subblocks. */
1871 static void
1872 instantiate_decls_1 (tree let)
1874 tree t;
1876 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1878 if (DECL_RTL_SET_P (t))
1879 instantiate_decl_rtl (DECL_RTL (t));
1880 if (VAR_P (t) && DECL_HAS_VALUE_EXPR_P (t))
1882 tree v = DECL_VALUE_EXPR (t);
1883 walk_tree (&v, instantiate_expr, NULL, NULL);
1887 /* Process all subblocks. */
1888 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1889 instantiate_decls_1 (t);
1892 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1893 all virtual registers in their DECL_RTL's. */
1895 static void
1896 instantiate_decls (tree fndecl)
1898 tree decl;
1899 unsigned ix;
1901 /* Process all parameters of the function. */
1902 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1904 instantiate_decl_rtl (DECL_RTL (decl));
1905 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1906 if (DECL_HAS_VALUE_EXPR_P (decl))
1908 tree v = DECL_VALUE_EXPR (decl);
1909 walk_tree (&v, instantiate_expr, NULL, NULL);
1913 if ((decl = DECL_RESULT (fndecl))
1914 && TREE_CODE (decl) == RESULT_DECL)
1916 if (DECL_RTL_SET_P (decl))
1917 instantiate_decl_rtl (DECL_RTL (decl));
1918 if (DECL_HAS_VALUE_EXPR_P (decl))
1920 tree v = DECL_VALUE_EXPR (decl);
1921 walk_tree (&v, instantiate_expr, NULL, NULL);
1925 /* Process the saved static chain if it exists. */
1926 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1927 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1928 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1930 /* Now process all variables defined in the function or its subblocks. */
1931 if (DECL_INITIAL (fndecl))
1932 instantiate_decls_1 (DECL_INITIAL (fndecl));
1934 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1935 if (DECL_RTL_SET_P (decl))
1936 instantiate_decl_rtl (DECL_RTL (decl));
1937 vec_free (cfun->local_decls);
1940 /* Pass through the INSNS of function FNDECL and convert virtual register
1941 references to hard register references. */
1943 static unsigned int
1944 instantiate_virtual_regs (void)
1946 rtx_insn *insn;
1948 /* Compute the offsets to use for this function. */
1949 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1950 var_offset = targetm.starting_frame_offset ();
1951 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1952 out_arg_offset = STACK_POINTER_OFFSET;
1953 #ifdef FRAME_POINTER_CFA_OFFSET
1954 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1955 #else
1956 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1957 #endif
1959 /* Initialize recognition, indicating that volatile is OK. */
1960 init_recog ();
1962 /* Scan through all the insns, instantiating every virtual register still
1963 present. */
1964 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1965 if (INSN_P (insn))
1967 /* These patterns in the instruction stream can never be recognized.
1968 Fortunately, they shouldn't contain virtual registers either. */
1969 if (GET_CODE (PATTERN (insn)) == USE
1970 || GET_CODE (PATTERN (insn)) == CLOBBER
1971 || GET_CODE (PATTERN (insn)) == ASM_INPUT
1972 || DEBUG_MARKER_INSN_P (insn))
1973 continue;
1974 else if (DEBUG_BIND_INSN_P (insn))
1975 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn));
1976 else
1977 instantiate_virtual_regs_in_insn (insn);
1979 if (insn->deleted ())
1980 continue;
1982 instantiate_virtual_regs_in_rtx (&REG_NOTES (insn));
1984 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1985 if (CALL_P (insn))
1986 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1989 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1990 instantiate_decls (current_function_decl);
1992 targetm.instantiate_decls ();
1994 /* Indicate that, from now on, assign_stack_local should use
1995 frame_pointer_rtx. */
1996 virtuals_instantiated = 1;
1998 return 0;
2001 namespace {
2003 const pass_data pass_data_instantiate_virtual_regs =
2005 RTL_PASS, /* type */
2006 "vregs", /* name */
2007 OPTGROUP_NONE, /* optinfo_flags */
2008 TV_NONE, /* tv_id */
2009 0, /* properties_required */
2010 0, /* properties_provided */
2011 0, /* properties_destroyed */
2012 0, /* todo_flags_start */
2013 0, /* todo_flags_finish */
2016 class pass_instantiate_virtual_regs : public rtl_opt_pass
2018 public:
2019 pass_instantiate_virtual_regs (gcc::context *ctxt)
2020 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2023 /* opt_pass methods: */
2024 virtual unsigned int execute (function *)
2026 return instantiate_virtual_regs ();
2029 }; // class pass_instantiate_virtual_regs
2031 } // anon namespace
2033 rtl_opt_pass *
2034 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2036 return new pass_instantiate_virtual_regs (ctxt);
2040 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2041 This means a type for which function calls must pass an address to the
2042 function or get an address back from the function.
2043 EXP may be a type node or an expression (whose type is tested). */
2046 aggregate_value_p (const_tree exp, const_tree fntype)
2048 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2049 int i, regno, nregs;
2050 rtx reg;
2052 if (fntype)
2053 switch (TREE_CODE (fntype))
2055 case CALL_EXPR:
2057 tree fndecl = get_callee_fndecl (fntype);
2058 if (fndecl)
2059 fntype = TREE_TYPE (fndecl);
2060 else if (CALL_EXPR_FN (fntype))
2061 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2062 else
2063 /* For internal functions, assume nothing needs to be
2064 returned in memory. */
2065 return 0;
2067 break;
2068 case FUNCTION_DECL:
2069 fntype = TREE_TYPE (fntype);
2070 break;
2071 case FUNCTION_TYPE:
2072 case METHOD_TYPE:
2073 break;
2074 case IDENTIFIER_NODE:
2075 fntype = NULL_TREE;
2076 break;
2077 default:
2078 /* We don't expect other tree types here. */
2079 gcc_unreachable ();
2082 if (VOID_TYPE_P (type))
2083 return 0;
2085 /* If a record should be passed the same as its first (and only) member
2086 don't pass it as an aggregate. */
2087 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2088 return aggregate_value_p (first_field (type), fntype);
2090 /* If the front end has decided that this needs to be passed by
2091 reference, do so. */
2092 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2093 && DECL_BY_REFERENCE (exp))
2094 return 1;
2096 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2097 if (fntype && TREE_ADDRESSABLE (fntype))
2098 return 1;
2100 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2101 and thus can't be returned in registers. */
2102 if (TREE_ADDRESSABLE (type))
2103 return 1;
2105 if (TYPE_EMPTY_P (type))
2106 return 0;
2108 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2109 return 1;
2111 if (targetm.calls.return_in_memory (type, fntype))
2112 return 1;
2114 /* Make sure we have suitable call-clobbered regs to return
2115 the value in; if not, we must return it in memory. */
2116 reg = hard_function_value (type, 0, fntype, 0);
2118 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2119 it is OK. */
2120 if (!REG_P (reg))
2121 return 0;
2123 /* Use the default ABI if the type of the function isn't known.
2124 The scheme for handling interoperability between different ABIs
2125 requires us to be able to tell when we're calling a function with
2126 a nondefault ABI. */
2127 const predefined_function_abi &abi = (fntype
2128 ? fntype_abi (fntype)
2129 : default_function_abi);
2130 regno = REGNO (reg);
2131 nregs = hard_regno_nregs (regno, TYPE_MODE (type));
2132 for (i = 0; i < nregs; i++)
2133 if (!fixed_regs[regno + i] && !abi.clobbers_full_reg_p (regno + i))
2134 return 1;
2136 return 0;
2139 /* Return true if we should assign DECL a pseudo register; false if it
2140 should live on the local stack. */
2142 bool
2143 use_register_for_decl (const_tree decl)
2145 if (TREE_CODE (decl) == SSA_NAME)
2147 /* We often try to use the SSA_NAME, instead of its underlying
2148 decl, to get type information and guide decisions, to avoid
2149 differences of behavior between anonymous and named
2150 variables, but in this one case we have to go for the actual
2151 variable if there is one. The main reason is that, at least
2152 at -O0, we want to place user variables on the stack, but we
2153 don't mind using pseudos for anonymous or ignored temps.
2154 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2155 should go in pseudos, whereas their corresponding variables
2156 might have to go on the stack. So, disregarding the decl
2157 here would negatively impact debug info at -O0, enable
2158 coalescing between SSA_NAMEs that ought to get different
2159 stack/pseudo assignments, and get the incoming argument
2160 processing thoroughly confused by PARM_DECLs expected to live
2161 in stack slots but assigned to pseudos. */
2162 if (!SSA_NAME_VAR (decl))
2163 return TYPE_MODE (TREE_TYPE (decl)) != BLKmode
2164 && !(flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)));
2166 decl = SSA_NAME_VAR (decl);
2169 /* Honor volatile. */
2170 if (TREE_SIDE_EFFECTS (decl))
2171 return false;
2173 /* Honor addressability. */
2174 if (TREE_ADDRESSABLE (decl))
2175 return false;
2177 /* RESULT_DECLs are a bit special in that they're assigned without
2178 regard to use_register_for_decl, but we generally only store in
2179 them. If we coalesce their SSA NAMEs, we'd better return a
2180 result that matches the assignment in expand_function_start. */
2181 if (TREE_CODE (decl) == RESULT_DECL)
2183 /* If it's not an aggregate, we're going to use a REG or a
2184 PARALLEL containing a REG. */
2185 if (!aggregate_value_p (decl, current_function_decl))
2186 return true;
2188 /* If expand_function_start determines the return value, we'll
2189 use MEM if it's not by reference. */
2190 if (cfun->returns_pcc_struct
2191 || (targetm.calls.struct_value_rtx
2192 (TREE_TYPE (current_function_decl), 1)))
2193 return DECL_BY_REFERENCE (decl);
2195 /* Otherwise, we're taking an extra all.function_result_decl
2196 argument. It's set up in assign_parms_augmented_arg_list,
2197 under the (negated) conditions above, and then it's used to
2198 set up the RESULT_DECL rtl in assign_params, after looping
2199 over all parameters. Now, if the RESULT_DECL is not by
2200 reference, we'll use a MEM either way. */
2201 if (!DECL_BY_REFERENCE (decl))
2202 return false;
2204 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2205 the function_result_decl's assignment. Since it's a pointer,
2206 we can short-circuit a number of the tests below, and we must
2207 duplicat e them because we don't have the
2208 function_result_decl to test. */
2209 if (!targetm.calls.allocate_stack_slots_for_args ())
2210 return true;
2211 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2212 if (optimize)
2213 return true;
2214 /* We don't set DECL_REGISTER for the function_result_decl. */
2215 return false;
2218 /* Only register-like things go in registers. */
2219 if (DECL_MODE (decl) == BLKmode)
2220 return false;
2222 /* If -ffloat-store specified, don't put explicit float variables
2223 into registers. */
2224 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2225 propagates values across these stores, and it probably shouldn't. */
2226 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2227 return false;
2229 if (!targetm.calls.allocate_stack_slots_for_args ())
2230 return true;
2232 /* If we're not interested in tracking debugging information for
2233 this decl, then we can certainly put it in a register. */
2234 if (DECL_IGNORED_P (decl))
2235 return true;
2237 if (optimize)
2238 return true;
2240 if (!DECL_REGISTER (decl))
2241 return false;
2243 /* When not optimizing, disregard register keyword for types that
2244 could have methods, otherwise the methods won't be callable from
2245 the debugger. */
2246 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl)))
2247 return false;
2249 return true;
2252 /* Structures to communicate between the subroutines of assign_parms.
2253 The first holds data persistent across all parameters, the second
2254 is cleared out for each parameter. */
2256 struct assign_parm_data_all
2258 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2259 should become a job of the target or otherwise encapsulated. */
2260 CUMULATIVE_ARGS args_so_far_v;
2261 cumulative_args_t args_so_far;
2262 struct args_size stack_args_size;
2263 tree function_result_decl;
2264 tree orig_fnargs;
2265 rtx_insn *first_conversion_insn;
2266 rtx_insn *last_conversion_insn;
2267 HOST_WIDE_INT pretend_args_size;
2268 HOST_WIDE_INT extra_pretend_bytes;
2269 int reg_parm_stack_space;
2272 struct assign_parm_data_one
2274 tree nominal_type;
2275 function_arg_info arg;
2276 rtx entry_parm;
2277 rtx stack_parm;
2278 machine_mode nominal_mode;
2279 machine_mode passed_mode;
2280 struct locate_and_pad_arg_data locate;
2281 int partial;
2284 /* A subroutine of assign_parms. Initialize ALL. */
2286 static void
2287 assign_parms_initialize_all (struct assign_parm_data_all *all)
2289 tree fntype ATTRIBUTE_UNUSED;
2291 memset (all, 0, sizeof (*all));
2293 fntype = TREE_TYPE (current_function_decl);
2295 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2296 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2297 #else
2298 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2299 current_function_decl, -1);
2300 #endif
2301 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2303 #ifdef INCOMING_REG_PARM_STACK_SPACE
2304 all->reg_parm_stack_space
2305 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2306 #endif
2309 /* If ARGS contains entries with complex types, split the entry into two
2310 entries of the component type. Return a new list of substitutions are
2311 needed, else the old list. */
2313 static void
2314 split_complex_args (vec<tree> *args)
2316 unsigned i;
2317 tree p;
2319 FOR_EACH_VEC_ELT (*args, i, p)
2321 tree type = TREE_TYPE (p);
2322 if (TREE_CODE (type) == COMPLEX_TYPE
2323 && targetm.calls.split_complex_arg (type))
2325 tree decl;
2326 tree subtype = TREE_TYPE (type);
2327 bool addressable = TREE_ADDRESSABLE (p);
2329 /* Rewrite the PARM_DECL's type with its component. */
2330 p = copy_node (p);
2331 TREE_TYPE (p) = subtype;
2332 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2333 SET_DECL_MODE (p, VOIDmode);
2334 DECL_SIZE (p) = NULL;
2335 DECL_SIZE_UNIT (p) = NULL;
2336 /* If this arg must go in memory, put it in a pseudo here.
2337 We can't allow it to go in memory as per normal parms,
2338 because the usual place might not have the imag part
2339 adjacent to the real part. */
2340 DECL_ARTIFICIAL (p) = addressable;
2341 DECL_IGNORED_P (p) = addressable;
2342 TREE_ADDRESSABLE (p) = 0;
2343 layout_decl (p, 0);
2344 (*args)[i] = p;
2346 /* Build a second synthetic decl. */
2347 decl = build_decl (EXPR_LOCATION (p),
2348 PARM_DECL, NULL_TREE, subtype);
2349 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2350 DECL_ARTIFICIAL (decl) = addressable;
2351 DECL_IGNORED_P (decl) = addressable;
2352 layout_decl (decl, 0);
2353 args->safe_insert (++i, decl);
2358 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2359 the hidden struct return argument, and (abi willing) complex args.
2360 Return the new parameter list. */
2362 static vec<tree>
2363 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2365 tree fndecl = current_function_decl;
2366 tree fntype = TREE_TYPE (fndecl);
2367 vec<tree> fnargs = vNULL;
2368 tree arg;
2370 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2371 fnargs.safe_push (arg);
2373 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2375 /* If struct value address is treated as the first argument, make it so. */
2376 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2377 && ! cfun->returns_pcc_struct
2378 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2380 tree type = build_pointer_type (TREE_TYPE (fntype));
2381 tree decl;
2383 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2384 PARM_DECL, get_identifier (".result_ptr"), type);
2385 DECL_ARG_TYPE (decl) = type;
2386 DECL_ARTIFICIAL (decl) = 1;
2387 DECL_NAMELESS (decl) = 1;
2388 TREE_CONSTANT (decl) = 1;
2389 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2390 changes, the end of the RESULT_DECL handling block in
2391 use_register_for_decl must be adjusted to match. */
2393 DECL_CHAIN (decl) = all->orig_fnargs;
2394 all->orig_fnargs = decl;
2395 fnargs.safe_insert (0, decl);
2397 all->function_result_decl = decl;
2400 /* If the target wants to split complex arguments into scalars, do so. */
2401 if (targetm.calls.split_complex_arg)
2402 split_complex_args (&fnargs);
2404 return fnargs;
2407 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2408 data for the parameter. Incorporate ABI specifics such as pass-by-
2409 reference and type promotion. */
2411 static void
2412 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2413 struct assign_parm_data_one *data)
2415 int unsignedp;
2417 *data = assign_parm_data_one ();
2419 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2420 if (!cfun->stdarg)
2421 data->arg.named = 1; /* No variadic parms. */
2422 else if (DECL_CHAIN (parm))
2423 data->arg.named = 1; /* Not the last non-variadic parm. */
2424 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2425 data->arg.named = 1; /* Only variadic ones are unnamed. */
2426 else
2427 data->arg.named = 0; /* Treat as variadic. */
2429 data->nominal_type = TREE_TYPE (parm);
2430 data->arg.type = DECL_ARG_TYPE (parm);
2432 /* Look out for errors propagating this far. Also, if the parameter's
2433 type is void then its value doesn't matter. */
2434 if (TREE_TYPE (parm) == error_mark_node
2435 /* This can happen after weird syntax errors
2436 or if an enum type is defined among the parms. */
2437 || TREE_CODE (parm) != PARM_DECL
2438 || data->arg.type == NULL
2439 || VOID_TYPE_P (data->nominal_type))
2441 data->nominal_type = data->arg.type = void_type_node;
2442 data->nominal_mode = data->passed_mode = data->arg.mode = VOIDmode;
2443 return;
2446 /* Find mode of arg as it is passed, and mode of arg as it should be
2447 during execution of this function. */
2448 data->passed_mode = data->arg.mode = TYPE_MODE (data->arg.type);
2449 data->nominal_mode = TYPE_MODE (data->nominal_type);
2451 /* If the parm is to be passed as a transparent union or record, use the
2452 type of the first field for the tests below. We have already verified
2453 that the modes are the same. */
2454 if (RECORD_OR_UNION_TYPE_P (data->arg.type)
2455 && TYPE_TRANSPARENT_AGGR (data->arg.type))
2456 data->arg.type = TREE_TYPE (first_field (data->arg.type));
2458 /* See if this arg was passed by invisible reference. */
2459 if (apply_pass_by_reference_rules (&all->args_so_far_v, data->arg))
2461 data->nominal_type = data->arg.type;
2462 data->passed_mode = data->nominal_mode = data->arg.mode;
2465 /* Find mode as it is passed by the ABI. */
2466 unsignedp = TYPE_UNSIGNED (data->arg.type);
2467 data->arg.mode
2468 = promote_function_mode (data->arg.type, data->arg.mode, &unsignedp,
2469 TREE_TYPE (current_function_decl), 0);
2472 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2474 static void
2475 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2476 struct assign_parm_data_one *data, bool no_rtl)
2478 int varargs_pretend_bytes = 0;
2480 function_arg_info last_named_arg = data->arg;
2481 last_named_arg.named = true;
2482 targetm.calls.setup_incoming_varargs (all->args_so_far, last_named_arg,
2483 &varargs_pretend_bytes, no_rtl);
2485 /* If the back-end has requested extra stack space, record how much is
2486 needed. Do not change pretend_args_size otherwise since it may be
2487 nonzero from an earlier partial argument. */
2488 if (varargs_pretend_bytes > 0)
2489 all->pretend_args_size = varargs_pretend_bytes;
2492 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2493 the incoming location of the current parameter. */
2495 static void
2496 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2497 struct assign_parm_data_one *data)
2499 HOST_WIDE_INT pretend_bytes = 0;
2500 rtx entry_parm;
2501 bool in_regs;
2503 if (data->arg.mode == VOIDmode)
2505 data->entry_parm = data->stack_parm = const0_rtx;
2506 return;
2509 targetm.calls.warn_parameter_passing_abi (all->args_so_far,
2510 data->arg.type);
2512 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2513 data->arg);
2514 if (entry_parm == 0)
2515 data->arg.mode = data->passed_mode;
2517 /* Determine parm's home in the stack, in case it arrives in the stack
2518 or we should pretend it did. Compute the stack position and rtx where
2519 the argument arrives and its size.
2521 There is one complexity here: If this was a parameter that would
2522 have been passed in registers, but wasn't only because it is
2523 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2524 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2525 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2526 as it was the previous time. */
2527 in_regs = (entry_parm != 0);
2528 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2529 in_regs = true;
2530 #endif
2531 if (!in_regs && !data->arg.named)
2533 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2535 rtx tem;
2536 function_arg_info named_arg = data->arg;
2537 named_arg.named = true;
2538 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2539 named_arg);
2540 in_regs = tem != NULL;
2544 /* If this parameter was passed both in registers and in the stack, use
2545 the copy on the stack. */
2546 if (targetm.calls.must_pass_in_stack (data->arg))
2547 entry_parm = 0;
2549 if (entry_parm)
2551 int partial;
2553 partial = targetm.calls.arg_partial_bytes (all->args_so_far, data->arg);
2554 data->partial = partial;
2556 /* The caller might already have allocated stack space for the
2557 register parameters. */
2558 if (partial != 0 && all->reg_parm_stack_space == 0)
2560 /* Part of this argument is passed in registers and part
2561 is passed on the stack. Ask the prologue code to extend
2562 the stack part so that we can recreate the full value.
2564 PRETEND_BYTES is the size of the registers we need to store.
2565 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2566 stack space that the prologue should allocate.
2568 Internally, gcc assumes that the argument pointer is aligned
2569 to STACK_BOUNDARY bits. This is used both for alignment
2570 optimizations (see init_emit) and to locate arguments that are
2571 aligned to more than PARM_BOUNDARY bits. We must preserve this
2572 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2573 a stack boundary. */
2575 /* We assume at most one partial arg, and it must be the first
2576 argument on the stack. */
2577 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2579 pretend_bytes = partial;
2580 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2582 /* We want to align relative to the actual stack pointer, so
2583 don't include this in the stack size until later. */
2584 all->extra_pretend_bytes = all->pretend_args_size;
2588 locate_and_pad_parm (data->arg.mode, data->arg.type, in_regs,
2589 all->reg_parm_stack_space,
2590 entry_parm ? data->partial : 0, current_function_decl,
2591 &all->stack_args_size, &data->locate);
2593 /* Update parm_stack_boundary if this parameter is passed in the
2594 stack. */
2595 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2596 crtl->parm_stack_boundary = data->locate.boundary;
2598 /* Adjust offsets to include the pretend args. */
2599 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2600 data->locate.slot_offset.constant += pretend_bytes;
2601 data->locate.offset.constant += pretend_bytes;
2603 data->entry_parm = entry_parm;
2606 /* A subroutine of assign_parms. If there is actually space on the stack
2607 for this parm, count it in stack_args_size and return true. */
2609 static bool
2610 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2611 struct assign_parm_data_one *data)
2613 /* Trivially true if we've no incoming register. */
2614 if (data->entry_parm == NULL)
2616 /* Also true if we're partially in registers and partially not,
2617 since we've arranged to drop the entire argument on the stack. */
2618 else if (data->partial != 0)
2620 /* Also true if the target says that it's passed in both registers
2621 and on the stack. */
2622 else if (GET_CODE (data->entry_parm) == PARALLEL
2623 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2625 /* Also true if the target says that there's stack allocated for
2626 all register parameters. */
2627 else if (all->reg_parm_stack_space > 0)
2629 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2630 else
2631 return false;
2633 all->stack_args_size.constant += data->locate.size.constant;
2634 if (data->locate.size.var)
2635 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2637 return true;
2640 /* A subroutine of assign_parms. Given that this parameter is allocated
2641 stack space by the ABI, find it. */
2643 static void
2644 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2646 rtx offset_rtx, stack_parm;
2647 unsigned int align, boundary;
2649 /* If we're passing this arg using a reg, make its stack home the
2650 aligned stack slot. */
2651 if (data->entry_parm)
2652 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2653 else
2654 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2656 stack_parm = crtl->args.internal_arg_pointer;
2657 if (offset_rtx != const0_rtx)
2658 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2659 stack_parm = gen_rtx_MEM (data->arg.mode, stack_parm);
2661 if (!data->arg.pass_by_reference)
2663 set_mem_attributes (stack_parm, parm, 1);
2664 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2665 while promoted mode's size is needed. */
2666 if (data->arg.mode != BLKmode
2667 && data->arg.mode != DECL_MODE (parm))
2669 set_mem_size (stack_parm, GET_MODE_SIZE (data->arg.mode));
2670 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2672 poly_int64 offset = subreg_lowpart_offset (DECL_MODE (parm),
2673 data->arg.mode);
2674 if (maybe_ne (offset, 0))
2675 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2680 boundary = data->locate.boundary;
2681 align = BITS_PER_UNIT;
2683 /* If we're padding upward, we know that the alignment of the slot
2684 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2685 intentionally forcing upward padding. Otherwise we have to come
2686 up with a guess at the alignment based on OFFSET_RTX. */
2687 poly_int64 offset;
2688 if (data->locate.where_pad == PAD_NONE || data->entry_parm)
2689 align = boundary;
2690 else if (data->locate.where_pad == PAD_UPWARD)
2692 align = boundary;
2693 /* If the argument offset is actually more aligned than the nominal
2694 stack slot boundary, take advantage of that excess alignment.
2695 Don't make any assumptions if STACK_POINTER_OFFSET is in use. */
2696 if (poly_int_rtx_p (offset_rtx, &offset)
2697 && known_eq (STACK_POINTER_OFFSET, 0))
2699 unsigned int offset_align = known_alignment (offset) * BITS_PER_UNIT;
2700 if (offset_align == 0 || offset_align > STACK_BOUNDARY)
2701 offset_align = STACK_BOUNDARY;
2702 align = MAX (align, offset_align);
2705 else if (poly_int_rtx_p (offset_rtx, &offset))
2707 align = least_bit_hwi (boundary);
2708 unsigned int offset_align = known_alignment (offset) * BITS_PER_UNIT;
2709 if (offset_align != 0)
2710 align = MIN (align, offset_align);
2712 set_mem_align (stack_parm, align);
2714 if (data->entry_parm)
2715 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2717 data->stack_parm = stack_parm;
2720 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2721 always valid and contiguous. */
2723 static void
2724 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2726 rtx entry_parm = data->entry_parm;
2727 rtx stack_parm = data->stack_parm;
2729 /* If this parm was passed part in regs and part in memory, pretend it
2730 arrived entirely in memory by pushing the register-part onto the stack.
2731 In the special case of a DImode or DFmode that is split, we could put
2732 it together in a pseudoreg directly, but for now that's not worth
2733 bothering with. */
2734 if (data->partial != 0)
2736 /* Handle calls that pass values in multiple non-contiguous
2737 locations. The Irix 6 ABI has examples of this. */
2738 if (GET_CODE (entry_parm) == PARALLEL)
2739 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2740 data->arg.type, int_size_in_bytes (data->arg.type));
2741 else
2743 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2744 move_block_from_reg (REGNO (entry_parm),
2745 validize_mem (copy_rtx (stack_parm)),
2746 data->partial / UNITS_PER_WORD);
2749 entry_parm = stack_parm;
2752 /* If we didn't decide this parm came in a register, by default it came
2753 on the stack. */
2754 else if (entry_parm == NULL)
2755 entry_parm = stack_parm;
2757 /* When an argument is passed in multiple locations, we can't make use
2758 of this information, but we can save some copying if the whole argument
2759 is passed in a single register. */
2760 else if (GET_CODE (entry_parm) == PARALLEL
2761 && data->nominal_mode != BLKmode
2762 && data->passed_mode != BLKmode)
2764 size_t i, len = XVECLEN (entry_parm, 0);
2766 for (i = 0; i < len; i++)
2767 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2768 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2769 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2770 == data->passed_mode)
2771 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2773 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2774 break;
2778 data->entry_parm = entry_parm;
2781 /* A subroutine of assign_parms. Reconstitute any values which were
2782 passed in multiple registers and would fit in a single register. */
2784 static void
2785 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2787 rtx entry_parm = data->entry_parm;
2789 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2790 This can be done with register operations rather than on the
2791 stack, even if we will store the reconstituted parameter on the
2792 stack later. */
2793 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2795 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2796 emit_group_store (parmreg, entry_parm, data->arg.type,
2797 GET_MODE_SIZE (GET_MODE (entry_parm)));
2798 entry_parm = parmreg;
2801 data->entry_parm = entry_parm;
2804 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2805 always valid and properly aligned. */
2807 static void
2808 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2810 rtx stack_parm = data->stack_parm;
2812 /* If we can't trust the parm stack slot to be aligned enough for its
2813 ultimate type, don't use that slot after entry. We'll make another
2814 stack slot, if we need one. */
2815 if (stack_parm
2816 && ((GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm)
2817 && ((optab_handler (movmisalign_optab, data->nominal_mode)
2818 != CODE_FOR_nothing)
2819 || targetm.slow_unaligned_access (data->nominal_mode,
2820 MEM_ALIGN (stack_parm))))
2821 || (data->nominal_type
2822 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2823 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2824 stack_parm = NULL;
2826 /* If parm was passed in memory, and we need to convert it on entry,
2827 don't store it back in that same slot. */
2828 else if (data->entry_parm == stack_parm
2829 && data->nominal_mode != BLKmode
2830 && data->nominal_mode != data->passed_mode)
2831 stack_parm = NULL;
2833 /* If stack protection is in effect for this function, don't leave any
2834 pointers in their passed stack slots. */
2835 else if (crtl->stack_protect_guard
2836 && (flag_stack_protect == 2
2837 || data->arg.pass_by_reference
2838 || POINTER_TYPE_P (data->nominal_type)))
2839 stack_parm = NULL;
2841 data->stack_parm = stack_parm;
2844 /* A subroutine of assign_parms. Return true if the current parameter
2845 should be stored as a BLKmode in the current frame. */
2847 static bool
2848 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2850 if (data->nominal_mode == BLKmode)
2851 return true;
2852 if (GET_MODE (data->entry_parm) == BLKmode)
2853 return true;
2855 #ifdef BLOCK_REG_PADDING
2856 /* Only assign_parm_setup_block knows how to deal with register arguments
2857 that are padded at the least significant end. */
2858 if (REG_P (data->entry_parm)
2859 && known_lt (GET_MODE_SIZE (data->arg.mode), UNITS_PER_WORD)
2860 && (BLOCK_REG_PADDING (data->passed_mode, data->arg.type, 1)
2861 == (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2862 return true;
2863 #endif
2865 return false;
2868 /* A subroutine of assign_parms. Arrange for the parameter to be
2869 present and valid in DATA->STACK_RTL. */
2871 static void
2872 assign_parm_setup_block (struct assign_parm_data_all *all,
2873 tree parm, struct assign_parm_data_one *data)
2875 rtx entry_parm = data->entry_parm;
2876 rtx stack_parm = data->stack_parm;
2877 rtx target_reg = NULL_RTX;
2878 bool in_conversion_seq = false;
2879 HOST_WIDE_INT size;
2880 HOST_WIDE_INT size_stored;
2882 if (GET_CODE (entry_parm) == PARALLEL)
2883 entry_parm = emit_group_move_into_temps (entry_parm);
2885 /* If we want the parameter in a pseudo, don't use a stack slot. */
2886 if (is_gimple_reg (parm) && use_register_for_decl (parm))
2888 tree def = ssa_default_def (cfun, parm);
2889 gcc_assert (def);
2890 machine_mode mode = promote_ssa_mode (def, NULL);
2891 rtx reg = gen_reg_rtx (mode);
2892 if (GET_CODE (reg) != CONCAT)
2893 stack_parm = reg;
2894 else
2896 target_reg = reg;
2897 /* Avoid allocating a stack slot, if there isn't one
2898 preallocated by the ABI. It might seem like we should
2899 always prefer a pseudo, but converting between
2900 floating-point and integer modes goes through the stack
2901 on various machines, so it's better to use the reserved
2902 stack slot than to risk wasting it and allocating more
2903 for the conversion. */
2904 if (stack_parm == NULL_RTX)
2906 int save = generating_concat_p;
2907 generating_concat_p = 0;
2908 stack_parm = gen_reg_rtx (mode);
2909 generating_concat_p = save;
2912 data->stack_parm = NULL;
2915 size = int_size_in_bytes (data->arg.type);
2916 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2917 if (stack_parm == 0)
2919 HOST_WIDE_INT parm_align
2920 = (STRICT_ALIGNMENT
2921 ? MAX (DECL_ALIGN (parm), BITS_PER_WORD) : DECL_ALIGN (parm));
2923 SET_DECL_ALIGN (parm, parm_align);
2924 if (DECL_ALIGN (parm) > MAX_SUPPORTED_STACK_ALIGNMENT)
2926 rtx allocsize = gen_int_mode (size_stored, Pmode);
2927 get_dynamic_stack_size (&allocsize, 0, DECL_ALIGN (parm), NULL);
2928 stack_parm = assign_stack_local (BLKmode, UINTVAL (allocsize),
2929 MAX_SUPPORTED_STACK_ALIGNMENT);
2930 rtx addr = align_dynamic_address (XEXP (stack_parm, 0),
2931 DECL_ALIGN (parm));
2932 mark_reg_pointer (addr, DECL_ALIGN (parm));
2933 stack_parm = gen_rtx_MEM (GET_MODE (stack_parm), addr);
2934 MEM_NOTRAP_P (stack_parm) = 1;
2936 else
2937 stack_parm = assign_stack_local (BLKmode, size_stored,
2938 DECL_ALIGN (parm));
2939 if (known_eq (GET_MODE_SIZE (GET_MODE (entry_parm)), size))
2940 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2941 set_mem_attributes (stack_parm, parm, 1);
2944 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2945 calls that pass values in multiple non-contiguous locations. */
2946 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2948 rtx mem;
2950 /* Note that we will be storing an integral number of words.
2951 So we have to be careful to ensure that we allocate an
2952 integral number of words. We do this above when we call
2953 assign_stack_local if space was not allocated in the argument
2954 list. If it was, this will not work if PARM_BOUNDARY is not
2955 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2956 if it becomes a problem. Exception is when BLKmode arrives
2957 with arguments not conforming to word_mode. */
2959 if (data->stack_parm == 0)
2961 else if (GET_CODE (entry_parm) == PARALLEL)
2963 else
2964 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2966 mem = validize_mem (copy_rtx (stack_parm));
2968 /* Handle values in multiple non-contiguous locations. */
2969 if (GET_CODE (entry_parm) == PARALLEL && !MEM_P (mem))
2970 emit_group_store (mem, entry_parm, data->arg.type, size);
2971 else if (GET_CODE (entry_parm) == PARALLEL)
2973 push_to_sequence2 (all->first_conversion_insn,
2974 all->last_conversion_insn);
2975 emit_group_store (mem, entry_parm, data->arg.type, size);
2976 all->first_conversion_insn = get_insns ();
2977 all->last_conversion_insn = get_last_insn ();
2978 end_sequence ();
2979 in_conversion_seq = true;
2982 else if (size == 0)
2985 /* If SIZE is that of a mode no bigger than a word, just use
2986 that mode's store operation. */
2987 else if (size <= UNITS_PER_WORD)
2989 unsigned int bits = size * BITS_PER_UNIT;
2990 machine_mode mode = int_mode_for_size (bits, 0).else_blk ();
2992 if (mode != BLKmode
2993 #ifdef BLOCK_REG_PADDING
2994 && (size == UNITS_PER_WORD
2995 || (BLOCK_REG_PADDING (mode, data->arg.type, 1)
2996 != (BYTES_BIG_ENDIAN ? PAD_UPWARD : PAD_DOWNWARD)))
2997 #endif
3000 rtx reg;
3002 /* We are really truncating a word_mode value containing
3003 SIZE bytes into a value of mode MODE. If such an
3004 operation requires no actual instructions, we can refer
3005 to the value directly in mode MODE, otherwise we must
3006 start with the register in word_mode and explicitly
3007 convert it. */
3008 if (targetm.truly_noop_truncation (size * BITS_PER_UNIT,
3009 BITS_PER_WORD))
3010 reg = gen_rtx_REG (mode, REGNO (entry_parm));
3011 else
3013 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3014 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
3016 emit_move_insn (change_address (mem, mode, 0), reg);
3019 #ifdef BLOCK_REG_PADDING
3020 /* Storing the register in memory as a full word, as
3021 move_block_from_reg below would do, and then using the
3022 MEM in a smaller mode, has the effect of shifting right
3023 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3024 shifting must be explicit. */
3025 else if (!MEM_P (mem))
3027 rtx x;
3029 /* If the assert below fails, we should have taken the
3030 mode != BLKmode path above, unless we have downward
3031 padding of smaller-than-word arguments on a machine
3032 with little-endian bytes, which would likely require
3033 additional changes to work correctly. */
3034 gcc_checking_assert (BYTES_BIG_ENDIAN
3035 && (BLOCK_REG_PADDING (mode,
3036 data->arg.type, 1)
3037 == PAD_UPWARD));
3039 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3041 x = gen_rtx_REG (word_mode, REGNO (entry_parm));
3042 x = expand_shift (RSHIFT_EXPR, word_mode, x, by,
3043 NULL_RTX, 1);
3044 x = force_reg (word_mode, x);
3045 x = gen_lowpart_SUBREG (GET_MODE (mem), x);
3047 emit_move_insn (mem, x);
3049 #endif
3051 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3052 machine must be aligned to the left before storing
3053 to memory. Note that the previous test doesn't
3054 handle all cases (e.g. SIZE == 3). */
3055 else if (size != UNITS_PER_WORD
3056 #ifdef BLOCK_REG_PADDING
3057 && (BLOCK_REG_PADDING (mode, data->arg.type, 1)
3058 == PAD_DOWNWARD)
3059 #else
3060 && BYTES_BIG_ENDIAN
3061 #endif
3064 rtx tem, x;
3065 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3066 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3068 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
3069 tem = change_address (mem, word_mode, 0);
3070 emit_move_insn (tem, x);
3072 else
3073 move_block_from_reg (REGNO (entry_parm), mem,
3074 size_stored / UNITS_PER_WORD);
3076 else if (!MEM_P (mem))
3078 gcc_checking_assert (size > UNITS_PER_WORD);
3079 #ifdef BLOCK_REG_PADDING
3080 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem),
3081 data->arg.type, 0)
3082 == PAD_UPWARD);
3083 #endif
3084 emit_move_insn (mem, entry_parm);
3086 else
3087 move_block_from_reg (REGNO (entry_parm), mem,
3088 size_stored / UNITS_PER_WORD);
3090 else if (data->stack_parm == 0)
3092 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3093 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
3094 BLOCK_OP_NORMAL);
3095 all->first_conversion_insn = get_insns ();
3096 all->last_conversion_insn = get_last_insn ();
3097 end_sequence ();
3098 in_conversion_seq = true;
3101 if (target_reg)
3103 if (!in_conversion_seq)
3104 emit_move_insn (target_reg, stack_parm);
3105 else
3107 push_to_sequence2 (all->first_conversion_insn,
3108 all->last_conversion_insn);
3109 emit_move_insn (target_reg, stack_parm);
3110 all->first_conversion_insn = get_insns ();
3111 all->last_conversion_insn = get_last_insn ();
3112 end_sequence ();
3114 stack_parm = target_reg;
3117 data->stack_parm = stack_parm;
3118 set_parm_rtl (parm, stack_parm);
3121 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3122 parameter. Get it there. Perform all ABI specified conversions. */
3124 static void
3125 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
3126 struct assign_parm_data_one *data)
3128 rtx parmreg, validated_mem;
3129 rtx equiv_stack_parm;
3130 machine_mode promoted_nominal_mode;
3131 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
3132 bool did_conversion = false;
3133 bool need_conversion, moved;
3134 enum insn_code icode;
3135 rtx rtl;
3137 /* Store the parm in a pseudoregister during the function, but we may
3138 need to do it in a wider mode. Using 2 here makes the result
3139 consistent with promote_decl_mode and thus expand_expr_real_1. */
3140 promoted_nominal_mode
3141 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
3142 TREE_TYPE (current_function_decl), 2);
3144 parmreg = gen_reg_rtx (promoted_nominal_mode);
3145 if (!DECL_ARTIFICIAL (parm))
3146 mark_user_reg (parmreg);
3148 /* If this was an item that we received a pointer to,
3149 set rtl appropriately. */
3150 if (data->arg.pass_by_reference)
3152 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->arg.type)), parmreg);
3153 set_mem_attributes (rtl, parm, 1);
3155 else
3156 rtl = parmreg;
3158 assign_parm_remove_parallels (data);
3160 /* Copy the value into the register, thus bridging between
3161 assign_parm_find_data_types and expand_expr_real_1. */
3163 equiv_stack_parm = data->stack_parm;
3164 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3166 need_conversion = (data->nominal_mode != data->passed_mode
3167 || promoted_nominal_mode != data->arg.mode);
3168 moved = false;
3170 if (need_conversion
3171 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3172 && data->nominal_mode == data->passed_mode
3173 && data->nominal_mode == GET_MODE (data->entry_parm))
3175 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3176 mode, by the caller. We now have to convert it to
3177 NOMINAL_MODE, if different. However, PARMREG may be in
3178 a different mode than NOMINAL_MODE if it is being stored
3179 promoted.
3181 If ENTRY_PARM is a hard register, it might be in a register
3182 not valid for operating in its mode (e.g., an odd-numbered
3183 register for a DFmode). In that case, moves are the only
3184 thing valid, so we can't do a convert from there. This
3185 occurs when the calling sequence allow such misaligned
3186 usages.
3188 In addition, the conversion may involve a call, which could
3189 clobber parameters which haven't been copied to pseudo
3190 registers yet.
3192 First, we try to emit an insn which performs the necessary
3193 conversion. We verify that this insn does not clobber any
3194 hard registers. */
3196 rtx op0, op1;
3198 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3199 unsignedp);
3201 op0 = parmreg;
3202 op1 = validated_mem;
3203 if (icode != CODE_FOR_nothing
3204 && insn_operand_matches (icode, 0, op0)
3205 && insn_operand_matches (icode, 1, op1))
3207 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3208 rtx_insn *insn, *insns;
3209 rtx t = op1;
3210 HARD_REG_SET hardregs;
3212 start_sequence ();
3213 /* If op1 is a hard register that is likely spilled, first
3214 force it into a pseudo, otherwise combiner might extend
3215 its lifetime too much. */
3216 if (GET_CODE (t) == SUBREG)
3217 t = SUBREG_REG (t);
3218 if (REG_P (t)
3219 && HARD_REGISTER_P (t)
3220 && ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
3221 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
3223 t = gen_reg_rtx (GET_MODE (op1));
3224 emit_move_insn (t, op1);
3226 else
3227 t = op1;
3228 rtx_insn *pat = gen_extend_insn (op0, t, promoted_nominal_mode,
3229 data->passed_mode, unsignedp);
3230 emit_insn (pat);
3231 insns = get_insns ();
3233 moved = true;
3234 CLEAR_HARD_REG_SET (hardregs);
3235 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3237 if (INSN_P (insn))
3238 note_stores (insn, record_hard_reg_sets, &hardregs);
3239 if (!hard_reg_set_empty_p (hardregs))
3240 moved = false;
3243 end_sequence ();
3245 if (moved)
3247 emit_insn (insns);
3248 if (equiv_stack_parm != NULL_RTX)
3249 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3250 equiv_stack_parm);
3255 if (moved)
3256 /* Nothing to do. */
3258 else if (need_conversion)
3260 /* We did not have an insn to convert directly, or the sequence
3261 generated appeared unsafe. We must first copy the parm to a
3262 pseudo reg, and save the conversion until after all
3263 parameters have been moved. */
3265 int save_tree_used;
3266 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3268 emit_move_insn (tempreg, validated_mem);
3270 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3271 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3273 if (partial_subreg_p (tempreg)
3274 && GET_MODE (tempreg) == data->nominal_mode
3275 && REG_P (SUBREG_REG (tempreg))
3276 && data->nominal_mode == data->passed_mode
3277 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm))
3279 /* The argument is already sign/zero extended, so note it
3280 into the subreg. */
3281 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3282 SUBREG_PROMOTED_SET (tempreg, unsignedp);
3285 /* TREE_USED gets set erroneously during expand_assignment. */
3286 save_tree_used = TREE_USED (parm);
3287 SET_DECL_RTL (parm, rtl);
3288 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3289 SET_DECL_RTL (parm, NULL_RTX);
3290 TREE_USED (parm) = save_tree_used;
3291 all->first_conversion_insn = get_insns ();
3292 all->last_conversion_insn = get_last_insn ();
3293 end_sequence ();
3295 did_conversion = true;
3297 else if (MEM_P (data->entry_parm)
3298 && GET_MODE_ALIGNMENT (promoted_nominal_mode)
3299 > MEM_ALIGN (data->entry_parm)
3300 && (((icode = optab_handler (movmisalign_optab,
3301 promoted_nominal_mode))
3302 != CODE_FOR_nothing)
3303 || targetm.slow_unaligned_access (promoted_nominal_mode,
3304 MEM_ALIGN (data->entry_parm))))
3306 if (icode != CODE_FOR_nothing)
3307 emit_insn (GEN_FCN (icode) (parmreg, validated_mem));
3308 else
3309 rtl = parmreg = extract_bit_field (validated_mem,
3310 GET_MODE_BITSIZE (promoted_nominal_mode), 0,
3311 unsignedp, parmreg,
3312 promoted_nominal_mode, VOIDmode, false, NULL);
3314 else
3315 emit_move_insn (parmreg, validated_mem);
3317 /* If we were passed a pointer but the actual value can safely live
3318 in a register, retrieve it and use it directly. */
3319 if (data->arg.pass_by_reference && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3321 /* We can't use nominal_mode, because it will have been set to
3322 Pmode above. We must use the actual mode of the parm. */
3323 if (use_register_for_decl (parm))
3325 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3326 mark_user_reg (parmreg);
3328 else
3330 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3331 TYPE_MODE (TREE_TYPE (parm)),
3332 TYPE_ALIGN (TREE_TYPE (parm)));
3333 parmreg
3334 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3335 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3336 align);
3337 set_mem_attributes (parmreg, parm, 1);
3340 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3341 the debug info in case it is not legitimate. */
3342 if (GET_MODE (parmreg) != GET_MODE (rtl))
3344 rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
3345 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3347 push_to_sequence2 (all->first_conversion_insn,
3348 all->last_conversion_insn);
3349 emit_move_insn (tempreg, rtl);
3350 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3351 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
3352 tempreg);
3353 all->first_conversion_insn = get_insns ();
3354 all->last_conversion_insn = get_last_insn ();
3355 end_sequence ();
3357 did_conversion = true;
3359 else
3360 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
3362 rtl = parmreg;
3364 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3365 now the parm. */
3366 data->stack_parm = NULL;
3369 set_parm_rtl (parm, rtl);
3371 /* Mark the register as eliminable if we did no conversion and it was
3372 copied from memory at a fixed offset, and the arg pointer was not
3373 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3374 offset formed an invalid address, such memory-equivalences as we
3375 make here would screw up life analysis for it. */
3376 if (data->nominal_mode == data->passed_mode
3377 && !did_conversion
3378 && data->stack_parm != 0
3379 && MEM_P (data->stack_parm)
3380 && data->locate.offset.var == 0
3381 && reg_mentioned_p (virtual_incoming_args_rtx,
3382 XEXP (data->stack_parm, 0)))
3384 rtx_insn *linsn = get_last_insn ();
3385 rtx_insn *sinsn;
3386 rtx set;
3388 /* Mark complex types separately. */
3389 if (GET_CODE (parmreg) == CONCAT)
3391 scalar_mode submode = GET_MODE_INNER (GET_MODE (parmreg));
3392 int regnor = REGNO (XEXP (parmreg, 0));
3393 int regnoi = REGNO (XEXP (parmreg, 1));
3394 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3395 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3396 GET_MODE_SIZE (submode));
3398 /* Scan backwards for the set of the real and
3399 imaginary parts. */
3400 for (sinsn = linsn; sinsn != 0;
3401 sinsn = prev_nonnote_insn (sinsn))
3403 set = single_set (sinsn);
3404 if (set == 0)
3405 continue;
3407 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3408 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3409 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3410 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3413 else
3414 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3417 /* For pointer data type, suggest pointer register. */
3418 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3419 mark_reg_pointer (parmreg,
3420 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3423 /* A subroutine of assign_parms. Allocate stack space to hold the current
3424 parameter. Get it there. Perform all ABI specified conversions. */
3426 static void
3427 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3428 struct assign_parm_data_one *data)
3430 /* Value must be stored in the stack slot STACK_PARM during function
3431 execution. */
3432 bool to_conversion = false;
3434 assign_parm_remove_parallels (data);
3436 if (data->arg.mode != data->nominal_mode)
3438 /* Conversion is required. */
3439 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3441 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3443 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3444 to_conversion = true;
3446 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3447 TYPE_UNSIGNED (TREE_TYPE (parm)));
3449 if (data->stack_parm)
3451 poly_int64 offset
3452 = subreg_lowpart_offset (data->nominal_mode,
3453 GET_MODE (data->stack_parm));
3454 /* ??? This may need a big-endian conversion on sparc64. */
3455 data->stack_parm
3456 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3457 if (maybe_ne (offset, 0) && MEM_OFFSET_KNOWN_P (data->stack_parm))
3458 set_mem_offset (data->stack_parm,
3459 MEM_OFFSET (data->stack_parm) + offset);
3463 if (data->entry_parm != data->stack_parm)
3465 rtx src, dest;
3467 if (data->stack_parm == 0)
3469 int align = STACK_SLOT_ALIGNMENT (data->arg.type,
3470 GET_MODE (data->entry_parm),
3471 TYPE_ALIGN (data->arg.type));
3472 if (align < (int)GET_MODE_ALIGNMENT (GET_MODE (data->entry_parm))
3473 && ((optab_handler (movmisalign_optab,
3474 GET_MODE (data->entry_parm))
3475 != CODE_FOR_nothing)
3476 || targetm.slow_unaligned_access (GET_MODE (data->entry_parm),
3477 align)))
3478 align = GET_MODE_ALIGNMENT (GET_MODE (data->entry_parm));
3479 data->stack_parm
3480 = assign_stack_local (GET_MODE (data->entry_parm),
3481 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3482 align);
3483 align = MEM_ALIGN (data->stack_parm);
3484 set_mem_attributes (data->stack_parm, parm, 1);
3485 set_mem_align (data->stack_parm, align);
3488 dest = validize_mem (copy_rtx (data->stack_parm));
3489 src = validize_mem (copy_rtx (data->entry_parm));
3491 if (MEM_P (src))
3493 /* Use a block move to handle potentially misaligned entry_parm. */
3494 if (!to_conversion)
3495 push_to_sequence2 (all->first_conversion_insn,
3496 all->last_conversion_insn);
3497 to_conversion = true;
3499 emit_block_move (dest, src,
3500 GEN_INT (int_size_in_bytes (data->arg.type)),
3501 BLOCK_OP_NORMAL);
3503 else
3505 if (!REG_P (src))
3506 src = force_reg (GET_MODE (src), src);
3507 emit_move_insn (dest, src);
3511 if (to_conversion)
3513 all->first_conversion_insn = get_insns ();
3514 all->last_conversion_insn = get_last_insn ();
3515 end_sequence ();
3518 set_parm_rtl (parm, data->stack_parm);
3521 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3522 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3524 static void
3525 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3526 vec<tree> fnargs)
3528 tree parm;
3529 tree orig_fnargs = all->orig_fnargs;
3530 unsigned i = 0;
3532 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3534 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3535 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3537 rtx tmp, real, imag;
3538 scalar_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3540 real = DECL_RTL (fnargs[i]);
3541 imag = DECL_RTL (fnargs[i + 1]);
3542 if (inner != GET_MODE (real))
3544 real = gen_lowpart_SUBREG (inner, real);
3545 imag = gen_lowpart_SUBREG (inner, imag);
3548 if (TREE_ADDRESSABLE (parm))
3550 rtx rmem, imem;
3551 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3552 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3553 DECL_MODE (parm),
3554 TYPE_ALIGN (TREE_TYPE (parm)));
3556 /* split_complex_arg put the real and imag parts in
3557 pseudos. Move them to memory. */
3558 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3559 set_mem_attributes (tmp, parm, 1);
3560 rmem = adjust_address_nv (tmp, inner, 0);
3561 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3562 push_to_sequence2 (all->first_conversion_insn,
3563 all->last_conversion_insn);
3564 emit_move_insn (rmem, real);
3565 emit_move_insn (imem, imag);
3566 all->first_conversion_insn = get_insns ();
3567 all->last_conversion_insn = get_last_insn ();
3568 end_sequence ();
3570 else
3571 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3572 set_parm_rtl (parm, tmp);
3574 real = DECL_INCOMING_RTL (fnargs[i]);
3575 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3576 if (inner != GET_MODE (real))
3578 real = gen_lowpart_SUBREG (inner, real);
3579 imag = gen_lowpart_SUBREG (inner, imag);
3581 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3582 set_decl_incoming_rtl (parm, tmp, false);
3583 i++;
3588 /* Assign RTL expressions to the function's parameters. This may involve
3589 copying them into registers and using those registers as the DECL_RTL. */
3591 static void
3592 assign_parms (tree fndecl)
3594 struct assign_parm_data_all all;
3595 tree parm;
3596 vec<tree> fnargs;
3597 unsigned i;
3599 crtl->args.internal_arg_pointer
3600 = targetm.calls.internal_arg_pointer ();
3602 assign_parms_initialize_all (&all);
3603 fnargs = assign_parms_augmented_arg_list (&all);
3605 FOR_EACH_VEC_ELT (fnargs, i, parm)
3607 struct assign_parm_data_one data;
3609 /* Extract the type of PARM; adjust it according to ABI. */
3610 assign_parm_find_data_types (&all, parm, &data);
3612 /* Early out for errors and void parameters. */
3613 if (data.passed_mode == VOIDmode)
3615 SET_DECL_RTL (parm, const0_rtx);
3616 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3617 continue;
3620 /* Estimate stack alignment from parameter alignment. */
3621 if (SUPPORTS_STACK_ALIGNMENT)
3623 unsigned int align
3624 = targetm.calls.function_arg_boundary (data.arg.mode,
3625 data.arg.type);
3626 align = MINIMUM_ALIGNMENT (data.arg.type, data.arg.mode, align);
3627 if (TYPE_ALIGN (data.nominal_type) > align)
3628 align = MINIMUM_ALIGNMENT (data.nominal_type,
3629 TYPE_MODE (data.nominal_type),
3630 TYPE_ALIGN (data.nominal_type));
3631 if (crtl->stack_alignment_estimated < align)
3633 gcc_assert (!crtl->stack_realign_processed);
3634 crtl->stack_alignment_estimated = align;
3638 /* Find out where the parameter arrives in this function. */
3639 assign_parm_find_entry_rtl (&all, &data);
3641 /* Find out where stack space for this parameter might be. */
3642 if (assign_parm_is_stack_parm (&all, &data))
3644 assign_parm_find_stack_rtl (parm, &data);
3645 assign_parm_adjust_entry_rtl (&data);
3647 /* Record permanently how this parm was passed. */
3648 if (data.arg.pass_by_reference)
3650 rtx incoming_rtl
3651 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.arg.type)),
3652 data.entry_parm);
3653 set_decl_incoming_rtl (parm, incoming_rtl, true);
3655 else
3656 set_decl_incoming_rtl (parm, data.entry_parm, false);
3658 assign_parm_adjust_stack_rtl (&data);
3660 if (assign_parm_setup_block_p (&data))
3661 assign_parm_setup_block (&all, parm, &data);
3662 else if (data.arg.pass_by_reference || use_register_for_decl (parm))
3663 assign_parm_setup_reg (&all, parm, &data);
3664 else
3665 assign_parm_setup_stack (&all, parm, &data);
3667 if (cfun->stdarg && !DECL_CHAIN (parm))
3668 assign_parms_setup_varargs (&all, &data, false);
3670 /* Update info on where next arg arrives in registers. */
3671 targetm.calls.function_arg_advance (all.args_so_far, data.arg);
3674 if (targetm.calls.split_complex_arg)
3675 assign_parms_unsplit_complex (&all, fnargs);
3677 fnargs.release ();
3679 /* Output all parameter conversion instructions (possibly including calls)
3680 now that all parameters have been copied out of hard registers. */
3681 emit_insn (all.first_conversion_insn);
3683 /* Estimate reload stack alignment from scalar return mode. */
3684 if (SUPPORTS_STACK_ALIGNMENT)
3686 if (DECL_RESULT (fndecl))
3688 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3689 machine_mode mode = TYPE_MODE (type);
3691 if (mode != BLKmode
3692 && mode != VOIDmode
3693 && !AGGREGATE_TYPE_P (type))
3695 unsigned int align = GET_MODE_ALIGNMENT (mode);
3696 if (crtl->stack_alignment_estimated < align)
3698 gcc_assert (!crtl->stack_realign_processed);
3699 crtl->stack_alignment_estimated = align;
3705 /* If we are receiving a struct value address as the first argument, set up
3706 the RTL for the function result. As this might require code to convert
3707 the transmitted address to Pmode, we do this here to ensure that possible
3708 preliminary conversions of the address have been emitted already. */
3709 if (all.function_result_decl)
3711 tree result = DECL_RESULT (current_function_decl);
3712 rtx addr = DECL_RTL (all.function_result_decl);
3713 rtx x;
3715 if (DECL_BY_REFERENCE (result))
3717 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3718 x = addr;
3720 else
3722 SET_DECL_VALUE_EXPR (result,
3723 build1 (INDIRECT_REF, TREE_TYPE (result),
3724 all.function_result_decl));
3725 addr = convert_memory_address (Pmode, addr);
3726 x = gen_rtx_MEM (DECL_MODE (result), addr);
3727 set_mem_attributes (x, result, 1);
3730 DECL_HAS_VALUE_EXPR_P (result) = 1;
3732 set_parm_rtl (result, x);
3735 /* We have aligned all the args, so add space for the pretend args. */
3736 crtl->args.pretend_args_size = all.pretend_args_size;
3737 all.stack_args_size.constant += all.extra_pretend_bytes;
3738 crtl->args.size = all.stack_args_size.constant;
3740 /* Adjust function incoming argument size for alignment and
3741 minimum length. */
3743 crtl->args.size = upper_bound (crtl->args.size, all.reg_parm_stack_space);
3744 crtl->args.size = aligned_upper_bound (crtl->args.size,
3745 PARM_BOUNDARY / BITS_PER_UNIT);
3747 if (ARGS_GROW_DOWNWARD)
3749 crtl->args.arg_offset_rtx
3750 = (all.stack_args_size.var == 0
3751 ? gen_int_mode (-all.stack_args_size.constant, Pmode)
3752 : expand_expr (size_diffop (all.stack_args_size.var,
3753 size_int (-all.stack_args_size.constant)),
3754 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3756 else
3757 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3759 /* See how many bytes, if any, of its args a function should try to pop
3760 on return. */
3762 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3763 TREE_TYPE (fndecl),
3764 crtl->args.size);
3766 /* For stdarg.h function, save info about
3767 regs and stack space used by the named args. */
3769 crtl->args.info = all.args_so_far_v;
3771 /* Set the rtx used for the function return value. Put this in its
3772 own variable so any optimizers that need this information don't have
3773 to include tree.h. Do this here so it gets done when an inlined
3774 function gets output. */
3776 crtl->return_rtx
3777 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3778 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3780 /* If scalar return value was computed in a pseudo-reg, or was a named
3781 return value that got dumped to the stack, copy that to the hard
3782 return register. */
3783 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3785 tree decl_result = DECL_RESULT (fndecl);
3786 rtx decl_rtl = DECL_RTL (decl_result);
3788 if (REG_P (decl_rtl)
3789 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3790 : DECL_REGISTER (decl_result))
3792 rtx real_decl_rtl;
3794 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3795 fndecl, true);
3796 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3797 /* The delay slot scheduler assumes that crtl->return_rtx
3798 holds the hard register containing the return value, not a
3799 temporary pseudo. */
3800 crtl->return_rtx = real_decl_rtl;
3805 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3806 For all seen types, gimplify their sizes. */
3808 static tree
3809 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3811 tree t = *tp;
3813 *walk_subtrees = 0;
3814 if (TYPE_P (t))
3816 if (POINTER_TYPE_P (t))
3817 *walk_subtrees = 1;
3818 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3819 && !TYPE_SIZES_GIMPLIFIED (t))
3821 gimplify_type_sizes (t, (gimple_seq *) data);
3822 *walk_subtrees = 1;
3826 return NULL;
3829 /* Gimplify the parameter list for current_function_decl. This involves
3830 evaluating SAVE_EXPRs of variable sized parameters and generating code
3831 to implement callee-copies reference parameters. Returns a sequence of
3832 statements to add to the beginning of the function. */
3834 gimple_seq
3835 gimplify_parameters (gimple_seq *cleanup)
3837 struct assign_parm_data_all all;
3838 tree parm;
3839 gimple_seq stmts = NULL;
3840 vec<tree> fnargs;
3841 unsigned i;
3843 assign_parms_initialize_all (&all);
3844 fnargs = assign_parms_augmented_arg_list (&all);
3846 FOR_EACH_VEC_ELT (fnargs, i, parm)
3848 struct assign_parm_data_one data;
3850 /* Extract the type of PARM; adjust it according to ABI. */
3851 assign_parm_find_data_types (&all, parm, &data);
3853 /* Early out for errors and void parameters. */
3854 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3855 continue;
3857 /* Update info on where next arg arrives in registers. */
3858 targetm.calls.function_arg_advance (all.args_so_far, data.arg);
3860 /* ??? Once upon a time variable_size stuffed parameter list
3861 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3862 turned out to be less than manageable in the gimple world.
3863 Now we have to hunt them down ourselves. */
3864 walk_tree_without_duplicates (&data.arg.type,
3865 gimplify_parm_type, &stmts);
3867 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3869 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3870 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3873 if (data.arg.pass_by_reference)
3875 tree type = TREE_TYPE (data.arg.type);
3876 function_arg_info orig_arg (type, data.arg.named);
3877 if (reference_callee_copied (&all.args_so_far_v, orig_arg))
3879 tree local, t;
3881 /* For constant-sized objects, this is trivial; for
3882 variable-sized objects, we have to play games. */
3883 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3884 && !(flag_stack_check == GENERIC_STACK_CHECK
3885 && compare_tree_int (DECL_SIZE_UNIT (parm),
3886 STACK_CHECK_MAX_VAR_SIZE) > 0))
3888 local = create_tmp_var (type, get_name (parm));
3889 DECL_IGNORED_P (local) = 0;
3890 /* If PARM was addressable, move that flag over
3891 to the local copy, as its address will be taken,
3892 not the PARMs. Keep the parms address taken
3893 as we'll query that flag during gimplification. */
3894 if (TREE_ADDRESSABLE (parm))
3895 TREE_ADDRESSABLE (local) = 1;
3896 else if (TREE_CODE (type) == COMPLEX_TYPE
3897 || TREE_CODE (type) == VECTOR_TYPE)
3898 DECL_GIMPLE_REG_P (local) = 1;
3900 if (!is_gimple_reg (local)
3901 && flag_stack_reuse != SR_NONE)
3903 tree clobber = build_clobber (type);
3904 gimple *clobber_stmt;
3905 clobber_stmt = gimple_build_assign (local, clobber);
3906 gimple_seq_add_stmt (cleanup, clobber_stmt);
3909 else
3911 tree ptr_type, addr;
3913 ptr_type = build_pointer_type (type);
3914 addr = create_tmp_reg (ptr_type, get_name (parm));
3915 DECL_IGNORED_P (addr) = 0;
3916 local = build_fold_indirect_ref (addr);
3918 t = build_alloca_call_expr (DECL_SIZE_UNIT (parm),
3919 DECL_ALIGN (parm),
3920 max_int_size_in_bytes (type));
3921 /* The call has been built for a variable-sized object. */
3922 CALL_ALLOCA_FOR_VAR_P (t) = 1;
3923 t = fold_convert (ptr_type, t);
3924 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3925 gimplify_and_add (t, &stmts);
3928 gimplify_assign (local, parm, &stmts);
3930 SET_DECL_VALUE_EXPR (parm, local);
3931 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3936 fnargs.release ();
3938 return stmts;
3941 /* Compute the size and offset from the start of the stacked arguments for a
3942 parm passed in mode PASSED_MODE and with type TYPE.
3944 INITIAL_OFFSET_PTR points to the current offset into the stacked
3945 arguments.
3947 The starting offset and size for this parm are returned in
3948 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3949 nonzero, the offset is that of stack slot, which is returned in
3950 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3951 padding required from the initial offset ptr to the stack slot.
3953 IN_REGS is nonzero if the argument will be passed in registers. It will
3954 never be set if REG_PARM_STACK_SPACE is not defined.
3956 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3957 for arguments which are passed in registers.
3959 FNDECL is the function in which the argument was defined.
3961 There are two types of rounding that are done. The first, controlled by
3962 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3963 argument list to be aligned to the specific boundary (in bits). This
3964 rounding affects the initial and starting offsets, but not the argument
3965 size.
3967 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3968 optionally rounds the size of the parm to PARM_BOUNDARY. The
3969 initial offset is not affected by this rounding, while the size always
3970 is and the starting offset may be. */
3972 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3973 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3974 callers pass in the total size of args so far as
3975 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3977 void
3978 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
3979 int reg_parm_stack_space, int partial,
3980 tree fndecl ATTRIBUTE_UNUSED,
3981 struct args_size *initial_offset_ptr,
3982 struct locate_and_pad_arg_data *locate)
3984 tree sizetree;
3985 pad_direction where_pad;
3986 unsigned int boundary, round_boundary;
3987 int part_size_in_regs;
3989 /* If we have found a stack parm before we reach the end of the
3990 area reserved for registers, skip that area. */
3991 if (! in_regs)
3993 if (reg_parm_stack_space > 0)
3995 if (initial_offset_ptr->var
3996 || !ordered_p (initial_offset_ptr->constant,
3997 reg_parm_stack_space))
3999 initial_offset_ptr->var
4000 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4001 ssize_int (reg_parm_stack_space));
4002 initial_offset_ptr->constant = 0;
4004 else
4005 initial_offset_ptr->constant
4006 = ordered_max (initial_offset_ptr->constant,
4007 reg_parm_stack_space);
4011 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
4013 sizetree = (type
4014 ? arg_size_in_bytes (type)
4015 : size_int (GET_MODE_SIZE (passed_mode)));
4016 where_pad = targetm.calls.function_arg_padding (passed_mode, type);
4017 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
4018 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
4019 type);
4020 locate->where_pad = where_pad;
4022 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4023 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
4024 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
4026 locate->boundary = boundary;
4028 if (SUPPORTS_STACK_ALIGNMENT)
4030 /* stack_alignment_estimated can't change after stack has been
4031 realigned. */
4032 if (crtl->stack_alignment_estimated < boundary)
4034 if (!crtl->stack_realign_processed)
4035 crtl->stack_alignment_estimated = boundary;
4036 else
4038 /* If stack is realigned and stack alignment value
4039 hasn't been finalized, it is OK not to increase
4040 stack_alignment_estimated. The bigger alignment
4041 requirement is recorded in stack_alignment_needed
4042 below. */
4043 gcc_assert (!crtl->stack_realign_finalized
4044 && crtl->stack_realign_needed);
4049 if (ARGS_GROW_DOWNWARD)
4051 locate->slot_offset.constant = -initial_offset_ptr->constant;
4052 if (initial_offset_ptr->var)
4053 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4054 initial_offset_ptr->var);
4057 tree s2 = sizetree;
4058 if (where_pad != PAD_NONE
4059 && (!tree_fits_uhwi_p (sizetree)
4060 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4061 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4062 SUB_PARM_SIZE (locate->slot_offset, s2);
4065 locate->slot_offset.constant += part_size_in_regs;
4067 if (!in_regs || reg_parm_stack_space > 0)
4068 pad_to_arg_alignment (&locate->slot_offset, boundary,
4069 &locate->alignment_pad);
4071 locate->size.constant = (-initial_offset_ptr->constant
4072 - locate->slot_offset.constant);
4073 if (initial_offset_ptr->var)
4074 locate->size.var = size_binop (MINUS_EXPR,
4075 size_binop (MINUS_EXPR,
4076 ssize_int (0),
4077 initial_offset_ptr->var),
4078 locate->slot_offset.var);
4080 /* Pad_below needs the pre-rounded size to know how much to pad
4081 below. */
4082 locate->offset = locate->slot_offset;
4083 if (where_pad == PAD_DOWNWARD)
4084 pad_below (&locate->offset, passed_mode, sizetree);
4087 else
4089 if (!in_regs || reg_parm_stack_space > 0)
4090 pad_to_arg_alignment (initial_offset_ptr, boundary,
4091 &locate->alignment_pad);
4092 locate->slot_offset = *initial_offset_ptr;
4094 #ifdef PUSH_ROUNDING
4095 if (passed_mode != BLKmode)
4096 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4097 #endif
4099 /* Pad_below needs the pre-rounded size to know how much to pad below
4100 so this must be done before rounding up. */
4101 locate->offset = locate->slot_offset;
4102 if (where_pad == PAD_DOWNWARD)
4103 pad_below (&locate->offset, passed_mode, sizetree);
4105 if (where_pad != PAD_NONE
4106 && (!tree_fits_uhwi_p (sizetree)
4107 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4108 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4110 ADD_PARM_SIZE (locate->size, sizetree);
4112 locate->size.constant -= part_size_in_regs;
4115 locate->offset.constant
4116 += targetm.calls.function_arg_offset (passed_mode, type);
4119 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4120 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4122 static void
4123 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4124 struct args_size *alignment_pad)
4126 tree save_var = NULL_TREE;
4127 poly_int64 save_constant = 0;
4128 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4129 poly_int64 sp_offset = STACK_POINTER_OFFSET;
4131 #ifdef SPARC_STACK_BOUNDARY_HACK
4132 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4133 the real alignment of %sp. However, when it does this, the
4134 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4135 if (SPARC_STACK_BOUNDARY_HACK)
4136 sp_offset = 0;
4137 #endif
4139 if (boundary > PARM_BOUNDARY)
4141 save_var = offset_ptr->var;
4142 save_constant = offset_ptr->constant;
4145 alignment_pad->var = NULL_TREE;
4146 alignment_pad->constant = 0;
4148 if (boundary > BITS_PER_UNIT)
4150 int misalign;
4151 if (offset_ptr->var
4152 || !known_misalignment (offset_ptr->constant + sp_offset,
4153 boundary_in_bytes, &misalign))
4155 tree sp_offset_tree = ssize_int (sp_offset);
4156 tree offset = size_binop (PLUS_EXPR,
4157 ARGS_SIZE_TREE (*offset_ptr),
4158 sp_offset_tree);
4159 tree rounded;
4160 if (ARGS_GROW_DOWNWARD)
4161 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4162 else
4163 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4165 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4166 /* ARGS_SIZE_TREE includes constant term. */
4167 offset_ptr->constant = 0;
4168 if (boundary > PARM_BOUNDARY)
4169 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4170 save_var);
4172 else
4174 if (ARGS_GROW_DOWNWARD)
4175 offset_ptr->constant -= misalign;
4176 else
4177 offset_ptr->constant += -misalign & (boundary_in_bytes - 1);
4179 if (boundary > PARM_BOUNDARY)
4180 alignment_pad->constant = offset_ptr->constant - save_constant;
4185 static void
4186 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4188 unsigned int align = PARM_BOUNDARY / BITS_PER_UNIT;
4189 int misalign;
4190 if (passed_mode != BLKmode
4191 && known_misalignment (GET_MODE_SIZE (passed_mode), align, &misalign))
4192 offset_ptr->constant += -misalign & (align - 1);
4193 else
4195 if (TREE_CODE (sizetree) != INTEGER_CST
4196 || (TREE_INT_CST_LOW (sizetree) & (align - 1)) != 0)
4198 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4199 tree s2 = round_up (sizetree, align);
4200 /* Add it in. */
4201 ADD_PARM_SIZE (*offset_ptr, s2);
4202 SUB_PARM_SIZE (*offset_ptr, sizetree);
4208 /* True if register REGNO was alive at a place where `setjmp' was
4209 called and was set more than once or is an argument. Such regs may
4210 be clobbered by `longjmp'. */
4212 static bool
4213 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4215 /* There appear to be cases where some local vars never reach the
4216 backend but have bogus regnos. */
4217 if (regno >= max_reg_num ())
4218 return false;
4220 return ((REG_N_SETS (regno) > 1
4221 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4222 regno))
4223 && REGNO_REG_SET_P (setjmp_crosses, regno));
4226 /* Walk the tree of blocks describing the binding levels within a
4227 function and warn about variables the might be killed by setjmp or
4228 vfork. This is done after calling flow_analysis before register
4229 allocation since that will clobber the pseudo-regs to hard
4230 regs. */
4232 static void
4233 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4235 tree decl, sub;
4237 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4239 if (VAR_P (decl)
4240 && DECL_RTL_SET_P (decl)
4241 && REG_P (DECL_RTL (decl))
4242 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4243 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4244 " %<longjmp%> or %<vfork%>", decl);
4247 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4248 setjmp_vars_warning (setjmp_crosses, sub);
4251 /* Do the appropriate part of setjmp_vars_warning
4252 but for arguments instead of local variables. */
4254 static void
4255 setjmp_args_warning (bitmap setjmp_crosses)
4257 tree decl;
4258 for (decl = DECL_ARGUMENTS (current_function_decl);
4259 decl; decl = DECL_CHAIN (decl))
4260 if (DECL_RTL (decl) != 0
4261 && REG_P (DECL_RTL (decl))
4262 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4263 warning (OPT_Wclobbered,
4264 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4265 decl);
4268 /* Generate warning messages for variables live across setjmp. */
4270 void
4271 generate_setjmp_warnings (void)
4273 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4275 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4276 || bitmap_empty_p (setjmp_crosses))
4277 return;
4279 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4280 setjmp_args_warning (setjmp_crosses);
4284 /* Reverse the order of elements in the fragment chain T of blocks,
4285 and return the new head of the chain (old last element).
4286 In addition to that clear BLOCK_SAME_RANGE flags when needed
4287 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4288 its super fragment origin. */
4290 static tree
4291 block_fragments_nreverse (tree t)
4293 tree prev = 0, block, next, prev_super = 0;
4294 tree super = BLOCK_SUPERCONTEXT (t);
4295 if (BLOCK_FRAGMENT_ORIGIN (super))
4296 super = BLOCK_FRAGMENT_ORIGIN (super);
4297 for (block = t; block; block = next)
4299 next = BLOCK_FRAGMENT_CHAIN (block);
4300 BLOCK_FRAGMENT_CHAIN (block) = prev;
4301 if ((prev && !BLOCK_SAME_RANGE (prev))
4302 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4303 != prev_super))
4304 BLOCK_SAME_RANGE (block) = 0;
4305 prev_super = BLOCK_SUPERCONTEXT (block);
4306 BLOCK_SUPERCONTEXT (block) = super;
4307 prev = block;
4309 t = BLOCK_FRAGMENT_ORIGIN (t);
4310 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4311 != prev_super)
4312 BLOCK_SAME_RANGE (t) = 0;
4313 BLOCK_SUPERCONTEXT (t) = super;
4314 return prev;
4317 /* Reverse the order of elements in the chain T of blocks,
4318 and return the new head of the chain (old last element).
4319 Also do the same on subblocks and reverse the order of elements
4320 in BLOCK_FRAGMENT_CHAIN as well. */
4322 static tree
4323 blocks_nreverse_all (tree t)
4325 tree prev = 0, block, next;
4326 for (block = t; block; block = next)
4328 next = BLOCK_CHAIN (block);
4329 BLOCK_CHAIN (block) = prev;
4330 if (BLOCK_FRAGMENT_CHAIN (block)
4331 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4333 BLOCK_FRAGMENT_CHAIN (block)
4334 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4335 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4336 BLOCK_SAME_RANGE (block) = 0;
4338 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4339 prev = block;
4341 return prev;
4345 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4346 and create duplicate blocks. */
4347 /* ??? Need an option to either create block fragments or to create
4348 abstract origin duplicates of a source block. It really depends
4349 on what optimization has been performed. */
4351 void
4352 reorder_blocks (void)
4354 tree block = DECL_INITIAL (current_function_decl);
4356 if (block == NULL_TREE)
4357 return;
4359 auto_vec<tree, 10> block_stack;
4361 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4362 clear_block_marks (block);
4364 /* Prune the old trees away, so that they don't get in the way. */
4365 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4366 BLOCK_CHAIN (block) = NULL_TREE;
4368 /* Recreate the block tree from the note nesting. */
4369 reorder_blocks_1 (get_insns (), block, &block_stack);
4370 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4373 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4375 void
4376 clear_block_marks (tree block)
4378 while (block)
4380 TREE_ASM_WRITTEN (block) = 0;
4381 clear_block_marks (BLOCK_SUBBLOCKS (block));
4382 block = BLOCK_CHAIN (block);
4386 static void
4387 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4388 vec<tree> *p_block_stack)
4390 rtx_insn *insn;
4391 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4393 for (insn = insns; insn; insn = NEXT_INSN (insn))
4395 if (NOTE_P (insn))
4397 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4399 tree block = NOTE_BLOCK (insn);
4400 tree origin;
4402 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4403 origin = block;
4405 if (prev_end)
4406 BLOCK_SAME_RANGE (prev_end) = 0;
4407 prev_end = NULL_TREE;
4409 /* If we have seen this block before, that means it now
4410 spans multiple address regions. Create a new fragment. */
4411 if (TREE_ASM_WRITTEN (block))
4413 tree new_block = copy_node (block);
4415 BLOCK_SAME_RANGE (new_block) = 0;
4416 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4417 BLOCK_FRAGMENT_CHAIN (new_block)
4418 = BLOCK_FRAGMENT_CHAIN (origin);
4419 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4421 NOTE_BLOCK (insn) = new_block;
4422 block = new_block;
4425 if (prev_beg == current_block && prev_beg)
4426 BLOCK_SAME_RANGE (block) = 1;
4428 prev_beg = origin;
4430 BLOCK_SUBBLOCKS (block) = 0;
4431 TREE_ASM_WRITTEN (block) = 1;
4432 /* When there's only one block for the entire function,
4433 current_block == block and we mustn't do this, it
4434 will cause infinite recursion. */
4435 if (block != current_block)
4437 tree super;
4438 if (block != origin)
4439 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4440 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4441 (origin))
4442 == current_block);
4443 if (p_block_stack->is_empty ())
4444 super = current_block;
4445 else
4447 super = p_block_stack->last ();
4448 gcc_assert (super == current_block
4449 || BLOCK_FRAGMENT_ORIGIN (super)
4450 == current_block);
4452 BLOCK_SUPERCONTEXT (block) = super;
4453 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4454 BLOCK_SUBBLOCKS (current_block) = block;
4455 current_block = origin;
4457 p_block_stack->safe_push (block);
4459 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4461 NOTE_BLOCK (insn) = p_block_stack->pop ();
4462 current_block = BLOCK_SUPERCONTEXT (current_block);
4463 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4464 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4465 prev_beg = NULL_TREE;
4466 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4467 ? NOTE_BLOCK (insn) : NULL_TREE;
4470 else
4472 prev_beg = NULL_TREE;
4473 if (prev_end)
4474 BLOCK_SAME_RANGE (prev_end) = 0;
4475 prev_end = NULL_TREE;
4480 /* Reverse the order of elements in the chain T of blocks,
4481 and return the new head of the chain (old last element). */
4483 tree
4484 blocks_nreverse (tree t)
4486 tree prev = 0, block, next;
4487 for (block = t; block; block = next)
4489 next = BLOCK_CHAIN (block);
4490 BLOCK_CHAIN (block) = prev;
4491 prev = block;
4493 return prev;
4496 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4497 by modifying the last node in chain 1 to point to chain 2. */
4499 tree
4500 block_chainon (tree op1, tree op2)
4502 tree t1;
4504 if (!op1)
4505 return op2;
4506 if (!op2)
4507 return op1;
4509 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4510 continue;
4511 BLOCK_CHAIN (t1) = op2;
4513 #ifdef ENABLE_TREE_CHECKING
4515 tree t2;
4516 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4517 gcc_assert (t2 != t1);
4519 #endif
4521 return op1;
4524 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4525 non-NULL, list them all into VECTOR, in a depth-first preorder
4526 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4527 blocks. */
4529 static int
4530 all_blocks (tree block, tree *vector)
4532 int n_blocks = 0;
4534 while (block)
4536 TREE_ASM_WRITTEN (block) = 0;
4538 /* Record this block. */
4539 if (vector)
4540 vector[n_blocks] = block;
4542 ++n_blocks;
4544 /* Record the subblocks, and their subblocks... */
4545 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4546 vector ? vector + n_blocks : 0);
4547 block = BLOCK_CHAIN (block);
4550 return n_blocks;
4553 /* Return a vector containing all the blocks rooted at BLOCK. The
4554 number of elements in the vector is stored in N_BLOCKS_P. The
4555 vector is dynamically allocated; it is the caller's responsibility
4556 to call `free' on the pointer returned. */
4558 static tree *
4559 get_block_vector (tree block, int *n_blocks_p)
4561 tree *block_vector;
4563 *n_blocks_p = all_blocks (block, NULL);
4564 block_vector = XNEWVEC (tree, *n_blocks_p);
4565 all_blocks (block, block_vector);
4567 return block_vector;
4570 static GTY(()) int next_block_index = 2;
4572 /* Set BLOCK_NUMBER for all the blocks in FN. */
4574 void
4575 number_blocks (tree fn)
4577 int i;
4578 int n_blocks;
4579 tree *block_vector;
4581 /* For XCOFF debugging output, we start numbering the blocks
4582 from 1 within each function, rather than keeping a running
4583 count. */
4584 #if defined (XCOFF_DEBUGGING_INFO)
4585 if (write_symbols == XCOFF_DEBUG)
4586 next_block_index = 1;
4587 #endif
4589 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4591 /* The top-level BLOCK isn't numbered at all. */
4592 for (i = 1; i < n_blocks; ++i)
4593 /* We number the blocks from two. */
4594 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4596 free (block_vector);
4598 return;
4601 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4603 DEBUG_FUNCTION tree
4604 debug_find_var_in_block_tree (tree var, tree block)
4606 tree t;
4608 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4609 if (t == var)
4610 return block;
4612 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4614 tree ret = debug_find_var_in_block_tree (var, t);
4615 if (ret)
4616 return ret;
4619 return NULL_TREE;
4622 /* Keep track of whether we're in a dummy function context. If we are,
4623 we don't want to invoke the set_current_function hook, because we'll
4624 get into trouble if the hook calls target_reinit () recursively or
4625 when the initial initialization is not yet complete. */
4627 static bool in_dummy_function;
4629 /* Invoke the target hook when setting cfun. Update the optimization options
4630 if the function uses different options than the default. */
4632 static void
4633 invoke_set_current_function_hook (tree fndecl)
4635 if (!in_dummy_function)
4637 tree opts = ((fndecl)
4638 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4639 : optimization_default_node);
4641 if (!opts)
4642 opts = optimization_default_node;
4644 /* Change optimization options if needed. */
4645 if (optimization_current_node != opts)
4647 optimization_current_node = opts;
4648 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4651 targetm.set_current_function (fndecl);
4652 this_fn_optabs = this_target_optabs;
4654 /* Initialize global alignment variables after op. */
4655 parse_alignment_opts ();
4657 if (opts != optimization_default_node)
4659 init_tree_optimization_optabs (opts);
4660 if (TREE_OPTIMIZATION_OPTABS (opts))
4661 this_fn_optabs = (struct target_optabs *)
4662 TREE_OPTIMIZATION_OPTABS (opts);
4667 /* cfun should never be set directly; use this function. */
4669 void
4670 set_cfun (struct function *new_cfun, bool force)
4672 if (cfun != new_cfun || force)
4674 cfun = new_cfun;
4675 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4676 redirect_edge_var_map_empty ();
4680 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4682 static vec<function *> cfun_stack;
4684 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4685 current_function_decl accordingly. */
4687 void
4688 push_cfun (struct function *new_cfun)
4690 gcc_assert ((!cfun && !current_function_decl)
4691 || (cfun && current_function_decl == cfun->decl));
4692 cfun_stack.safe_push (cfun);
4693 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4694 set_cfun (new_cfun);
4697 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4699 void
4700 pop_cfun (void)
4702 struct function *new_cfun = cfun_stack.pop ();
4703 /* When in_dummy_function, we do have a cfun but current_function_decl is
4704 NULL. We also allow pushing NULL cfun and subsequently changing
4705 current_function_decl to something else and have both restored by
4706 pop_cfun. */
4707 gcc_checking_assert (in_dummy_function
4708 || !cfun
4709 || current_function_decl == cfun->decl);
4710 set_cfun (new_cfun);
4711 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4714 /* Return value of funcdef and increase it. */
4716 get_next_funcdef_no (void)
4718 return funcdef_no++;
4721 /* Return value of funcdef. */
4723 get_last_funcdef_no (void)
4725 return funcdef_no;
4728 /* Allocate a function structure for FNDECL and set its contents
4729 to the defaults. Set cfun to the newly-allocated object.
4730 Some of the helper functions invoked during initialization assume
4731 that cfun has already been set. Therefore, assign the new object
4732 directly into cfun and invoke the back end hook explicitly at the
4733 very end, rather than initializing a temporary and calling set_cfun
4734 on it.
4736 ABSTRACT_P is true if this is a function that will never be seen by
4737 the middle-end. Such functions are front-end concepts (like C++
4738 function templates) that do not correspond directly to functions
4739 placed in object files. */
4741 void
4742 allocate_struct_function (tree fndecl, bool abstract_p)
4744 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4746 cfun = ggc_cleared_alloc<function> ();
4748 init_eh_for_function ();
4750 if (init_machine_status)
4751 cfun->machine = (*init_machine_status) ();
4753 #ifdef OVERRIDE_ABI_FORMAT
4754 OVERRIDE_ABI_FORMAT (fndecl);
4755 #endif
4757 if (fndecl != NULL_TREE)
4759 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4760 cfun->decl = fndecl;
4761 current_function_funcdef_no = get_next_funcdef_no ();
4764 invoke_set_current_function_hook (fndecl);
4766 if (fndecl != NULL_TREE)
4768 tree result = DECL_RESULT (fndecl);
4770 if (!abstract_p)
4772 /* Now that we have activated any function-specific attributes
4773 that might affect layout, particularly vector modes, relayout
4774 each of the parameters and the result. */
4775 relayout_decl (result);
4776 for (tree parm = DECL_ARGUMENTS (fndecl); parm;
4777 parm = DECL_CHAIN (parm))
4778 relayout_decl (parm);
4780 /* Similarly relayout the function decl. */
4781 targetm.target_option.relayout_function (fndecl);
4784 if (!abstract_p && aggregate_value_p (result, fndecl))
4786 #ifdef PCC_STATIC_STRUCT_RETURN
4787 cfun->returns_pcc_struct = 1;
4788 #endif
4789 cfun->returns_struct = 1;
4792 cfun->stdarg = stdarg_p (fntype);
4794 /* Assume all registers in stdarg functions need to be saved. */
4795 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4796 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4798 /* ??? This could be set on a per-function basis by the front-end
4799 but is this worth the hassle? */
4800 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4801 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4803 if (!profile_flag && !flag_instrument_function_entry_exit)
4804 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4807 /* Don't enable begin stmt markers if var-tracking at assignments is
4808 disabled. The markers make little sense without the variable
4809 binding annotations among them. */
4810 cfun->debug_nonbind_markers = lang_hooks.emits_begin_stmt
4811 && MAY_HAVE_DEBUG_MARKER_STMTS;
4814 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4815 instead of just setting it. */
4817 void
4818 push_struct_function (tree fndecl)
4820 /* When in_dummy_function we might be in the middle of a pop_cfun and
4821 current_function_decl and cfun may not match. */
4822 gcc_assert (in_dummy_function
4823 || (!cfun && !current_function_decl)
4824 || (cfun && current_function_decl == cfun->decl));
4825 cfun_stack.safe_push (cfun);
4826 current_function_decl = fndecl;
4827 allocate_struct_function (fndecl, false);
4830 /* Reset crtl and other non-struct-function variables to defaults as
4831 appropriate for emitting rtl at the start of a function. */
4833 static void
4834 prepare_function_start (void)
4836 gcc_assert (!get_last_insn ());
4838 if (in_dummy_function)
4839 crtl->abi = &default_function_abi;
4840 else
4841 crtl->abi = &fndecl_abi (cfun->decl).base_abi ();
4843 init_temp_slots ();
4844 init_emit ();
4845 init_varasm_status ();
4846 init_expr ();
4847 default_rtl_profile ();
4849 if (flag_stack_usage_info)
4851 cfun->su = ggc_cleared_alloc<stack_usage> ();
4852 cfun->su->static_stack_size = -1;
4855 cse_not_expected = ! optimize;
4857 /* Caller save not needed yet. */
4858 caller_save_needed = 0;
4860 /* We haven't done register allocation yet. */
4861 reg_renumber = 0;
4863 /* Indicate that we have not instantiated virtual registers yet. */
4864 virtuals_instantiated = 0;
4866 /* Indicate that we want CONCATs now. */
4867 generating_concat_p = 1;
4869 /* Indicate we have no need of a frame pointer yet. */
4870 frame_pointer_needed = 0;
4873 void
4874 push_dummy_function (bool with_decl)
4876 tree fn_decl, fn_type, fn_result_decl;
4878 gcc_assert (!in_dummy_function);
4879 in_dummy_function = true;
4881 if (with_decl)
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;
4890 else
4891 fn_decl = NULL_TREE;
4893 push_struct_function (fn_decl);
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. */
4901 void
4902 init_dummy_function_start (void)
4904 push_dummy_function (false);
4905 prepare_function_start ();
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. */
4912 void
4913 init_function_start (tree subr)
4915 /* Initialize backend, if needed. */
4916 initialize_rtl ();
4918 prepare_function_start ();
4919 decide_function_section (subr);
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");
4927 /* Expand code to verify the stack_protect_guard. This is invoked at
4928 the end of a function to be protected. */
4930 void
4931 stack_protect_epilogue (void)
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;
4938 x = expand_normal (crtl->stack_protect_guard);
4940 if (targetm.have_stack_protect_combined_test () && guard_decl)
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);
4950 else
4952 if (guard_decl)
4953 y = expand_normal (guard_decl);
4954 else
4955 y = const0_rtx;
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);
4963 if (seq)
4964 emit_insn (seq);
4965 else
4966 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
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);
4977 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
4978 free_temp_slots ();
4979 emit_label (label);
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. */
4988 void
4989 expand_function_start (tree subr)
4991 /* Make sure volatile mem refs aren't considered
4992 valid operands of arithmetic insns. */
4993 init_recog_no_volatile ();
4995 crtl->profile
4996 = (profile_flag
4997 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4999 crtl->limit_stack
5000 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
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 ();
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. */
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))
5015 /* Returning something that won't go in a register. */
5016 rtx value_address = 0;
5018 #ifdef PCC_STATIC_STRUCT_RETURN
5019 if (cfun->returns_pcc_struct)
5021 int size = int_size_in_bytes (TREE_TYPE (res));
5022 value_address = assemble_static_space (size);
5024 else
5025 #endif
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)
5033 value_address = gen_reg_rtx (Pmode);
5034 emit_move_insn (value_address, sv);
5037 if (value_address)
5039 rtx x = value_address;
5040 if (!DECL_BY_REFERENCE (res))
5042 x = gen_rtx_MEM (DECL_MODE (res), x);
5043 set_mem_attributes (x, res, 1);
5045 set_parm_rtl (res, x);
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
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);
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;
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
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);
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
5085 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5086 set_parm_rtl (res, gen_group_rtx (hard_reg));
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;
5095 /* Initialize rtx for parameters and local variables.
5096 In some cases this requires emitting insns. */
5097 assign_parms (subr);
5099 /* If function gets a static chain arg, store it. */
5100 if (cfun->static_chain_decl)
5102 tree parm = cfun->static_chain_decl;
5103 rtx local, chain;
5104 rtx_insn *insn;
5105 int unsignedp;
5107 local = gen_reg_rtx (promote_decl_mode (parm, &unsignedp));
5108 chain = targetm.calls.static_chain (current_function_decl, true);
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))));
5114 if (GET_MODE (local) != GET_MODE (chain))
5116 convert_move (local, chain, unsignedp);
5117 insn = get_last_insn ();
5119 else
5120 insn = emit_move_insn (local, chain);
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);
5127 /* If we aren't optimizing, save the static chain onto the stack. */
5128 if (!optimize)
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;
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);
5148 gcc_assert (NOTE_P (get_last_insn ()));
5150 parm_birth_insn = get_last_insn ();
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)
5156 tree t_save;
5157 rtx r_save;
5159 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5160 gcc_assert (DECL_RTL_SET_P (var));
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);
5169 emit_move_insn (r_save, hard_frame_pointer_rtx);
5170 update_nonlocal_goto_save_area ();
5173 if (crtl->profile)
5175 #ifdef PROFILE_HOOK
5176 PROFILE_HOOK (current_function_funcdef_no);
5177 #endif
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);
5185 void
5186 pop_dummy_function (void)
5188 pop_cfun ();
5189 in_dummy_function = false;
5192 /* Undo the effects of init_dummy_function_start. */
5193 void
5194 expand_dummy_function_end (void)
5196 gcc_assert (in_dummy_function);
5198 /* End any sequences that failed to be closed due to syntax errors. */
5199 while (in_sequence_p ())
5200 end_sequence ();
5202 /* Outside function body, can't compute type's actual size
5203 until next function's body starts. */
5205 free_after_parsing (cfun);
5206 free_after_compilation (cfun);
5207 pop_dummy_function ();
5210 /* Helper for diddle_return_value. */
5212 void
5213 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5215 if (! outgoing)
5216 return;
5218 if (REG_P (outgoing))
5219 (*doit) (outgoing, arg);
5220 else if (GET_CODE (outgoing) == PARALLEL)
5222 int i;
5224 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5226 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5228 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5229 (*doit) (x, arg);
5234 /* Call DOIT for each hard register used as a return value from
5235 the current function. */
5237 void
5238 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5240 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5243 static void
5244 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5246 emit_clobber (reg);
5249 void
5250 clobber_return_register (void)
5252 diddle_return_value (do_clobber_return_reg, NULL);
5254 /* In case we do use pseudo to return value, clobber it too. */
5255 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
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)
5261 do_clobber_return_reg (decl_rtl, NULL);
5266 static void
5267 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5269 emit_use (reg);
5272 static void
5273 use_return_register (void)
5275 diddle_return_value (do_use_return_reg, NULL);
5278 /* Generate RTL for the end of the current function. */
5280 void
5281 expand_function_end (void)
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 ();
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)
5293 rtx_insn *insn, *seq;
5295 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5296 if (CALL_P (insn))
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;
5312 /* End any sequences that failed to be closed due to syntax errors. */
5313 while (in_sequence_p ())
5314 end_sequence ();
5316 clear_pending_stack_adjust ();
5317 do_pending_stack_adjust ();
5319 /* Output a linenumber for the end of the function.
5320 SDB depended on this. */
5321 set_curr_insn_location (input_location);
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.
5329 We delay actual code generation after the current_function_value_rtx
5330 is computed. */
5331 rtx_insn *clobber_after = get_last_insn ();
5333 /* Output the label for the actual return from the function. */
5334 emit_label (return_label);
5336 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
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 ());
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 ();
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 ();
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)))
5359 tree decl_result = DECL_RESULT (current_function_decl);
5360 rtx decl_rtl = DECL_RTL (decl_result);
5362 if (REG_P (decl_rtl)
5363 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5364 : DECL_REGISTER (decl_result))
5366 rtx real_decl_rtl = crtl->return_rtx;
5367 complex_mode cmode;
5369 /* This should be set in assign_parms. */
5370 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
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));
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)))
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);
5392 else if (GET_CODE (real_decl_rtl) == PARALLEL)
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)));
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)
5411 int old_generating_concat_p;
5412 rtx tmp;
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;
5419 emit_move_insn (tmp, decl_rtl);
5420 emit_move_insn (real_decl_rtl, tmp);
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))
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);
5432 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5434 else
5435 emit_move_insn (real_decl_rtl, decl_rtl);
5439 /* If returning a structure, arrange to return the address of the value
5440 in a place where debuggers expect to find it.
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)
5448 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5449 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5450 rtx outgoing;
5452 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5453 type = TREE_TYPE (type);
5454 else
5455 value_address = XEXP (value_address, 0);
5457 outgoing = targetm.calls.function_value (build_pointer_type (type),
5458 current_function_decl, true);
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;
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);
5468 emit_move_insn (outgoing, value_address);
5470 /* Show return register used to hold result (in this case the address
5471 of the result. */
5472 crtl->return_rtx = outgoing;
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))
5480 start_sequence ();
5481 clobber_return_register ();
5482 rtx_insn *seq = get_insns ();
5483 end_sequence ();
5485 emit_insn_after (seq, clobber_after);
5488 /* Output the label for the naked return from the function. */
5489 if (naked_return_label)
5490 emit_label (naked_return_label);
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 ());
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 ();
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)
5511 rtx tem = 0;
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);
5519 emit_stack_restore (SAVE_FUNCTION, tem);
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 ();
5530 get_arg_pointer_save_area (void)
5532 rtx ret = arg_pointer_save_area;
5534 if (! ret)
5536 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5537 arg_pointer_save_area = ret;
5540 if (! crtl->arg_pointer_save_area_init)
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 ();
5551 push_topmost_sequence ();
5552 emit_insn_after (seq, entry_of_function ());
5553 pop_topmost_sequence ();
5555 crtl->arg_pointer_save_area_init = true;
5558 return ret;
5562 /* If debugging dumps are requested, dump information about how the
5563 target handled -fstack-check=clash for the prologue.
5565 PROBES describes what if any probes were emitted.
5567 RESIDUALS indicates if the prologue had any residual allocation
5568 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5570 void
5571 dump_stack_clash_frame_info (enum stack_clash_probes probes, bool residuals)
5573 if (!dump_file)
5574 return;
5576 switch (probes)
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;
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");
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");
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");
5613 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5614 for the first time. */
5616 static void
5617 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5619 rtx_insn *tmp;
5620 hash_table<insn_cache_hasher> *hash = *hashp;
5622 if (hash == NULL)
5623 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5625 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5627 rtx *slot = hash->find_slot (tmp, INSERT);
5628 gcc_assert (*slot == NULL);
5629 *slot = tmp;
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. */
5637 void
5638 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5640 hash_table<insn_cache_hasher> *hash;
5641 rtx *slot;
5643 hash = epilogue_insn_hash;
5644 if (!hash || !hash->find (insn))
5646 hash = prologue_insn_hash;
5647 if (!hash || !hash->find (insn))
5648 return;
5651 slot = hash->find_slot (copy, INSERT);
5652 gcc_assert (*slot == NULL);
5653 *slot = copy;
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. */
5659 static bool
5660 contains (const rtx_insn *insn, hash_table<insn_cache_hasher> *hash)
5662 if (hash == NULL)
5663 return false;
5665 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
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;
5675 return hash->find (const_cast<rtx_insn *> (insn)) != NULL;
5679 prologue_contains (const rtx_insn *insn)
5681 return contains (insn, prologue_insn_hash);
5685 epilogue_contains (const rtx_insn *insn)
5687 return contains (insn, epilogue_insn_hash);
5691 prologue_epilogue_contains (const rtx_insn *insn)
5693 if (contains (insn, prologue_insn_hash))
5694 return 1;
5695 if (contains (insn, epilogue_insn_hash))
5696 return 1;
5697 return 0;
5700 void
5701 record_prologue_seq (rtx_insn *seq)
5703 record_insns (seq, NULL, &prologue_insn_hash);
5706 void
5707 record_epilogue_seq (rtx_insn *seq)
5709 record_insns (seq, NULL, &epilogue_insn_hash);
5712 /* Set JUMP_LABEL for a return insn. */
5714 void
5715 set_return_jump_label (rtx_insn *returnjump)
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;
5726 /* Return a sequence to be used as the split prologue for the current
5727 function, or NULL. */
5729 static rtx_insn *
5730 make_split_prologue_seq (void)
5732 if (!flag_split_stack
5733 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl)))
5734 return NULL;
5736 start_sequence ();
5737 emit_insn (targetm.gen_split_stack_prologue ());
5738 rtx_insn *seq = get_insns ();
5739 end_sequence ();
5741 record_insns (seq, NULL, &prologue_insn_hash);
5742 set_insn_locations (seq, prologue_location);
5744 return seq;
5747 /* Return a sequence to be used as the prologue for the current function,
5748 or NULL. */
5750 static rtx_insn *
5751 make_prologue_seq (void)
5753 if (!targetm.have_prologue ())
5754 return NULL;
5756 start_sequence ();
5757 rtx_insn *seq = targetm.gen_prologue ();
5758 emit_insn (seq);
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);
5765 /* Retain a map of the prologue insns. */
5766 record_insns (seq, NULL, &prologue_insn_hash);
5767 emit_note (NOTE_INSN_PROLOGUE_END);
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 ());
5775 seq = get_insns ();
5776 end_sequence ();
5777 set_insn_locations (seq, prologue_location);
5779 return seq;
5782 /* Return a sequence to be used as the epilogue for the current function,
5783 or NULL. */
5785 static rtx_insn *
5786 make_epilogue_seq (void)
5788 if (!targetm.have_epilogue ())
5789 return NULL;
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);
5797 /* Retain a map of the epilogue insns. */
5798 record_insns (seq, NULL, &epilogue_insn_hash);
5799 set_insn_locations (seq, epilogue_location);
5801 seq = get_insns ();
5802 rtx_insn *returnjump = get_last_insn ();
5803 end_sequence ();
5805 if (JUMP_P (returnjump))
5806 set_return_jump_label (returnjump);
5808 return seq;
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.
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
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.
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.
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.
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.
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.
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. */
5860 void
5861 thread_prologue_and_epilogue_insns (void)
5863 df_analyze ();
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)));
5870 edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5871 edge orig_entry_edge = entry_edge;
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 ();
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);
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);
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)
5894 split_prologue_seq = make_split_prologue_seq ();
5895 prologue_seq = make_prologue_seq ();
5896 epilogue_seq = make_epilogue_seq ();
5899 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
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;
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)
5915 rtx_insn *prev, *last, *trial;
5917 if (e->flags & EDGE_FALLTHRU)
5918 continue;
5919 last = BB_END (e->src);
5920 if (!eh_returnjump_p (last))
5921 continue;
5923 prev = PREV_INSN (last);
5924 trial = try_split (PATTERN (last), last, 1);
5925 if (trial == last)
5926 continue;
5928 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5929 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5932 edge exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
5934 if (exit_fallthru_edge)
5936 if (epilogue_seq)
5938 insert_insn_on_edge (epilogue_seq, exit_fallthru_edge);
5939 commit_edge_insertions ();
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)
5945 if (((e->flags & EDGE_FALLTHRU) != 0)
5946 && returnjump_p (BB_END (e->src)))
5947 e->flags &= ~EDGE_FALLTHRU;
5950 else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
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 ();
5969 /* Insert the prologue. */
5971 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5973 if (split_prologue_seq || prologue_seq)
5975 rtx_insn *split_prologue_insn = split_prologue_seq;
5976 if (split_prologue_seq)
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);
5983 rtx_insn *prologue_insn = prologue_seq;
5984 if (prologue_seq)
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);
5991 commit_edge_insertions ();
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)
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);
6013 default_rtl_profile ();
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))
6020 /* Skip those already handled, the ones that run without prologue. */
6021 if (e->flags & EDGE_IGNORE)
6023 e->flags &= ~EDGE_IGNORE;
6024 continue;
6027 rtx_insn *insn = BB_END (e->src);
6029 if (!(CALL_P (insn) && SIBLING_CALL_P (insn)))
6030 continue;
6032 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6034 start_sequence ();
6035 emit_note (NOTE_INSN_EPILOGUE_BEG);
6036 emit_insn (ep_seq);
6037 rtx_insn *seq = get_insns ();
6038 end_sequence ();
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);
6046 emit_insn_before (seq, insn);
6050 if (epilogue_seq)
6052 rtx_insn *insn, *next;
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)
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));
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 ();
6074 /* Reposition the prologue-end and epilogue-begin notes after
6075 instruction scheduling. */
6077 void
6078 reposition_prologue_and_epilogue_notes (void)
6080 if (!targetm.have_prologue ()
6081 && !targetm.have_epilogue ()
6082 && !targetm.have_sibcall_epilogue ())
6083 return;
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)
6089 size_t len = prologue_insn_hash->elements ();
6090 rtx_insn *insn, *last = NULL, *note = NULL;
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))
6099 if (NOTE_P (insn))
6101 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6102 note = insn;
6104 else if (contains (insn, prologue_insn_hash))
6106 last = insn;
6107 if (--len == 0)
6108 break;
6112 if (last)
6114 if (note == NULL)
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))
6121 if (NOTE_P (note)
6122 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6123 break;
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);
6134 if (epilogue_insn_hash != NULL)
6136 edge_iterator ei;
6137 edge e;
6139 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6141 rtx_insn *insn, *first = NULL, *note = NULL;
6142 basic_block bb = e->src;
6144 /* Scan from the beginning until we reach the first epilogue insn. */
6145 FOR_BB_INSNS (bb, insn)
6147 if (NOTE_P (insn))
6149 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6151 note = insn;
6152 if (first != NULL)
6153 break;
6156 else if (first == NULL && contains (insn, epilogue_insn_hash))
6158 first = insn;
6159 if (note != NULL)
6160 break;
6164 if (note)
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);
6176 if (PREV_INSN (first) != note)
6177 reorder_insns (note, note, PREV_INSN (first));
6183 /* Returns the name of function declared by FNDECL. */
6184 const char *
6185 fndecl_name (tree fndecl)
6187 if (fndecl == NULL)
6188 return "(nofn)";
6189 return lang_hooks.decl_printable_name (fndecl, 1);
6192 /* Returns the name of function FN. */
6193 const char *
6194 function_name (struct function *fn)
6196 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6197 return fndecl_name (fndecl);
6200 /* Returns the name of the current function. */
6201 const char *
6202 current_function_name (void)
6204 return function_name (cfun);
6208 static unsigned int
6209 rest_of_handle_check_leaf_regs (void)
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;
6218 /* Insert a TYPE into the used types hash table of CFUN. */
6220 static void
6221 used_types_insert_helper (tree type, struct function *func)
6223 if (type != NULL && func != NULL)
6225 if (func->used_types_hash == NULL)
6226 func->used_types_hash = hash_set<tree>::create_ggc (37);
6228 func->used_types_hash->add (type);
6232 /* Given a type, insert it into the used hash table in cfun. */
6233 void
6234 used_types_insert (tree t)
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)
6248 if (cfun)
6249 used_types_insert_helper (t, cfun);
6250 else
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);
6260 /* Helper to Hash a struct types_used_by_vars_entry. */
6262 static hashval_t
6263 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6265 gcc_assert (entry && entry->var_decl && entry->type);
6267 return iterative_hash_object (entry->type,
6268 iterative_hash_object (entry->var_decl, 0));
6271 /* Hash function of the types_used_by_vars_entry hash table. */
6273 hashval_t
6274 used_type_hasher::hash (types_used_by_vars_entry *entry)
6276 return hash_types_used_by_vars_entry (entry);
6279 /*Equality function of the types_used_by_vars_entry hash table. */
6281 bool
6282 used_type_hasher::equal (types_used_by_vars_entry *e1,
6283 types_used_by_vars_entry *e2)
6285 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6288 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6290 void
6291 types_used_by_var_decl_insert (tree type, tree var_decl)
6293 if (type != NULL && var_decl != NULL)
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);
6303 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6304 if (*slot == NULL)
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;
6315 namespace {
6317 const pass_data pass_data_leaf_regs =
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 */
6330 class pass_leaf_regs : public rtl_opt_pass
6332 public:
6333 pass_leaf_regs (gcc::context *ctxt)
6334 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6337 /* opt_pass methods: */
6338 virtual unsigned int execute (function *)
6340 return rest_of_handle_check_leaf_regs ();
6343 }; // class pass_leaf_regs
6345 } // anon namespace
6347 rtl_opt_pass *
6348 make_pass_leaf_regs (gcc::context *ctxt)
6350 return new pass_leaf_regs (ctxt);
6353 static unsigned int
6354 rest_of_handle_thread_prologue_and_epilogue (void)
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);
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 ();
6367 /* Some non-cold blocks may now be only reachable from cold blocks.
6368 Fix that up. */
6369 fixup_partitions ();
6371 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6372 see PR57320. */
6373 cleanup_cfg (optimize ? CLEANUP_EXPENSIVE : 0);
6375 /* The stack usage info is finalized during prologue expansion. */
6376 if (flag_stack_usage_info)
6377 output_stack_usage ();
6379 return 0;
6382 namespace {
6384 const pass_data pass_data_thread_prologue_and_epilogue =
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 */
6397 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6399 public:
6400 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6401 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6404 /* opt_pass methods: */
6405 virtual unsigned int execute (function *)
6407 return rest_of_handle_thread_prologue_and_epilogue ();
6410 }; // class pass_thread_prologue_and_epilogue
6412 } // anon namespace
6414 rtl_opt_pass *
6415 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6417 return new pass_thread_prologue_and_epilogue (ctxt);
6421 /* If CONSTRAINT is a matching constraint, then return its number.
6422 Otherwise, return -1. */
6424 static int
6425 matching_constraint_num (const char *constraint)
6427 if (*constraint == '%')
6428 constraint++;
6430 if (IN_RANGE (*constraint, '0', '9'))
6431 return strtoul (constraint, NULL, 10);
6433 return -1;
6436 /* This mini-pass fixes fall-out from SSA in asm statements that have
6437 in-out constraints. Say you start with
6439 orig = inout;
6440 asm ("": "+mr" (inout));
6441 use (orig);
6443 which is transformed very early to use explicit output and match operands:
6445 orig = inout;
6446 asm ("": "=mr" (inout) : "0" (inout));
6447 use (orig);
6449 Or, after SSA and copyprop,
6451 asm ("": "=mr" (inout_2) : "0" (inout_1));
6452 use (inout_1);
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.
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
6471 asm ("": "=mr" (inout_2) : "0" (inout_1));
6473 back to
6475 inout_2 = inout_1;
6476 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6478 static void
6479 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
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);
6488 memset (output_matched, 0, noutputs * sizeof (bool));
6489 for (i = 0; i < ninputs; i++)
6491 rtx input, output;
6492 rtx_insn *insns;
6493 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6494 int match, j;
6496 match = matching_constraint_num (constraint);
6497 if (match < 0)
6498 continue;
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;
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;
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)
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;
6531 output_matched[match] = true;
6533 start_sequence ();
6534 emit_move_insn (output, copy_rtx (input));
6535 insns = get_insns ();
6536 end_sequence ();
6537 emit_insn_before (insns, insn);
6539 constraint = ASM_OPERANDS_OUTPUT_CONSTRAINT(SET_SRC(p_sets[match]));
6540 bool early_clobber_p = strchr (constraint, '&') != NULL;
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:
6549 asm ("" : "=r" (output), "=m" (input) : "0" (input))
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:
6556 output = input
6557 asm ("" : "=r" (output), "=m" (input) : "0" (output))
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.
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. */
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)))
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);
6586 changed = true;
6589 if (changed)
6590 df_insn_rescan (insn);
6593 /* Add the decl D to the local_decls list of FUN. */
6595 void
6596 add_local_decl (struct function *fun, tree d)
6598 gcc_assert (VAR_P (d));
6599 vec_safe_push (fun->local_decls, d);
6602 namespace {
6604 const pass_data pass_data_match_asm_constraints =
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 */
6617 class pass_match_asm_constraints : public rtl_opt_pass
6619 public:
6620 pass_match_asm_constraints (gcc::context *ctxt)
6621 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6624 /* opt_pass methods: */
6625 virtual unsigned int execute (function *);
6627 }; // class pass_match_asm_constraints
6629 unsigned
6630 pass_match_asm_constraints::execute (function *fun)
6632 basic_block bb;
6633 rtx_insn *insn;
6634 rtx pat, *p_sets;
6635 int noutputs;
6637 if (!crtl->has_asm_statement)
6638 return 0;
6640 df_set_flags (DF_DEFER_INSN_RESCAN);
6641 FOR_EACH_BB_FN (bb, fun)
6643 FOR_BB_INSNS (bb, insn)
6645 if (!INSN_P (insn))
6646 continue;
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;
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);
6662 return TODO_df_finish;
6665 } // anon namespace
6667 rtl_opt_pass *
6668 make_pass_match_asm_constraints (gcc::context *ctxt)
6670 return new pass_match_asm_constraints (ctxt);
6674 #include "gt-function.h"