[64/77] Add a scalar_mode class
[official-gcc.git] / gcc / function.c
blobaf5e050b8a6f50bc6ec0eb163b5e04aabbbec6ea
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2017 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-chkp.h"
77 #include "rtl-chkp.h"
78 #include "tree-dfa.h"
79 #include "tree-ssa.h"
80 #include "stringpool.h"
81 #include "attribs.h"
83 /* So we can assign to cfun in this file. */
84 #undef cfun
86 #ifndef STACK_ALIGNMENT_NEEDED
87 #define STACK_ALIGNMENT_NEEDED 1
88 #endif
90 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
92 /* Round a value to the lowest integer less than it that is a multiple of
93 the required alignment. Avoid using division in case the value is
94 negative. Assume the alignment is a power of two. */
95 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
97 /* Similar, but round to the next highest integer that meets the
98 alignment. */
99 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
101 /* Nonzero once virtual register instantiation has been done.
102 assign_stack_local uses frame_pointer_rtx when this is nonzero.
103 calls.c:emit_library_call_value_1 uses it to set up
104 post-instantiation libcalls. */
105 int virtuals_instantiated;
107 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
108 static GTY(()) int funcdef_no;
110 /* These variables hold pointers to functions to create and destroy
111 target specific, per-function data structures. */
112 struct machine_function * (*init_machine_status) (void);
114 /* The currently compiled function. */
115 struct function *cfun = 0;
117 /* These hashes record the prologue and epilogue insns. */
119 struct insn_cache_hasher : ggc_cache_ptr_hash<rtx_def>
121 static hashval_t hash (rtx x) { return htab_hash_pointer (x); }
122 static bool equal (rtx a, rtx b) { return a == b; }
125 static GTY((cache))
126 hash_table<insn_cache_hasher> *prologue_insn_hash;
127 static GTY((cache))
128 hash_table<insn_cache_hasher> *epilogue_insn_hash;
131 hash_table<used_type_hasher> *types_used_by_vars_hash = NULL;
132 vec<tree, va_gc> *types_used_by_cur_var_decl;
134 /* Forward declarations. */
136 static struct temp_slot *find_temp_slot_from_address (rtx);
137 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
138 static void pad_below (struct args_size *, machine_mode, tree);
139 static void reorder_blocks_1 (rtx_insn *, tree, vec<tree> *);
140 static int all_blocks (tree, tree *);
141 static tree *get_block_vector (tree, int *);
142 extern tree debug_find_var_in_block_tree (tree, tree);
143 /* We always define `record_insns' even if it's not used so that we
144 can always export `prologue_epilogue_contains'. */
145 static void record_insns (rtx_insn *, rtx, hash_table<insn_cache_hasher> **)
146 ATTRIBUTE_UNUSED;
147 static bool contains (const rtx_insn *, hash_table<insn_cache_hasher> *);
148 static void prepare_function_start (void);
149 static void do_clobber_return_reg (rtx, void *);
150 static void do_use_return_reg (rtx, void *);
153 /* Stack of nested functions. */
154 /* Keep track of the cfun stack. */
156 static vec<function *> function_context_stack;
158 /* Save the current context for compilation of a nested function.
159 This is called from language-specific code. */
161 void
162 push_function_context (void)
164 if (cfun == 0)
165 allocate_struct_function (NULL, false);
167 function_context_stack.safe_push (cfun);
168 set_cfun (NULL);
171 /* Restore the last saved context, at the end of a nested function.
172 This function is called from language-specific code. */
174 void
175 pop_function_context (void)
177 struct function *p = function_context_stack.pop ();
178 set_cfun (p);
179 current_function_decl = p->decl;
181 /* Reset variables that have known state during rtx generation. */
182 virtuals_instantiated = 0;
183 generating_concat_p = 1;
186 /* Clear out all parts of the state in F that can safely be discarded
187 after the function has been parsed, but not compiled, to let
188 garbage collection reclaim the memory. */
190 void
191 free_after_parsing (struct function *f)
193 f->language = 0;
196 /* Clear out all parts of the state in F that can safely be discarded
197 after the function has been compiled, to let garbage collection
198 reclaim the memory. */
200 void
201 free_after_compilation (struct function *f)
203 prologue_insn_hash = NULL;
204 epilogue_insn_hash = NULL;
206 free (crtl->emit.regno_pointer_align);
208 memset (crtl, 0, sizeof (struct rtl_data));
209 f->eh = NULL;
210 f->machine = NULL;
211 f->cfg = NULL;
212 f->curr_properties &= ~PROP_cfg;
214 regno_reg_rtx = NULL;
217 /* Return size needed for stack frame based on slots so far allocated.
218 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
219 the caller may have to do that. */
221 HOST_WIDE_INT
222 get_frame_size (void)
224 if (FRAME_GROWS_DOWNWARD)
225 return -frame_offset;
226 else
227 return frame_offset;
230 /* Issue an error message and return TRUE if frame OFFSET overflows in
231 the signed target pointer arithmetics for function FUNC. Otherwise
232 return FALSE. */
234 bool
235 frame_offset_overflow (HOST_WIDE_INT offset, tree func)
237 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
239 if (size > (HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (Pmode) - 1))
240 /* Leave room for the fixed part of the frame. */
241 - 64 * UNITS_PER_WORD)
243 error_at (DECL_SOURCE_LOCATION (func),
244 "total size of local objects too large");
245 return TRUE;
248 return FALSE;
251 /* Return the minimum spill slot alignment for a register of mode MODE. */
253 unsigned int
254 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED)
256 return STACK_SLOT_ALIGNMENT (NULL_TREE, mode, GET_MODE_ALIGNMENT (mode));
259 /* Return stack slot alignment in bits for TYPE and MODE. */
261 static unsigned int
262 get_stack_local_alignment (tree type, machine_mode mode)
264 unsigned int alignment;
266 if (mode == BLKmode)
267 alignment = BIGGEST_ALIGNMENT;
268 else
269 alignment = GET_MODE_ALIGNMENT (mode);
271 /* Allow the frond-end to (possibly) increase the alignment of this
272 stack slot. */
273 if (! type)
274 type = lang_hooks.types.type_for_mode (mode, 0);
276 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
279 /* Determine whether it is possible to fit a stack slot of size SIZE and
280 alignment ALIGNMENT into an area in the stack frame that starts at
281 frame offset START and has a length of LENGTH. If so, store the frame
282 offset to be used for the stack slot in *POFFSET and return true;
283 return false otherwise. This function will extend the frame size when
284 given a start/length pair that lies at the end of the frame. */
286 static bool
287 try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
288 HOST_WIDE_INT size, unsigned int alignment,
289 HOST_WIDE_INT *poffset)
291 HOST_WIDE_INT this_frame_offset;
292 int frame_off, frame_alignment, frame_phase;
294 /* Calculate how many bytes the start of local variables is off from
295 stack alignment. */
296 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
297 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
298 frame_phase = frame_off ? frame_alignment - frame_off : 0;
300 /* Round the frame offset to the specified alignment. */
302 /* We must be careful here, since FRAME_OFFSET might be negative and
303 division with a negative dividend isn't as well defined as we might
304 like. So we instead assume that ALIGNMENT is a power of two and
305 use logical operations which are unambiguous. */
306 if (FRAME_GROWS_DOWNWARD)
307 this_frame_offset
308 = (FLOOR_ROUND (start + length - size - frame_phase,
309 (unsigned HOST_WIDE_INT) alignment)
310 + frame_phase);
311 else
312 this_frame_offset
313 = (CEIL_ROUND (start - frame_phase,
314 (unsigned HOST_WIDE_INT) alignment)
315 + frame_phase);
317 /* See if it fits. If this space is at the edge of the frame,
318 consider extending the frame to make it fit. Our caller relies on
319 this when allocating a new slot. */
320 if (frame_offset == start && this_frame_offset < frame_offset)
321 frame_offset = this_frame_offset;
322 else if (this_frame_offset < start)
323 return false;
324 else if (start + length == frame_offset
325 && this_frame_offset + size > start + length)
326 frame_offset = this_frame_offset + size;
327 else if (this_frame_offset + size > start + length)
328 return false;
330 *poffset = this_frame_offset;
331 return true;
334 /* Create a new frame_space structure describing free space in the stack
335 frame beginning at START and ending at END, and chain it into the
336 function's frame_space_list. */
338 static void
339 add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
341 struct frame_space *space = ggc_alloc<frame_space> ();
342 space->next = crtl->frame_space_list;
343 crtl->frame_space_list = space;
344 space->start = start;
345 space->length = end - start;
348 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
349 with machine mode MODE.
351 ALIGN controls the amount of alignment for the address of the slot:
352 0 means according to MODE,
353 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
354 -2 means use BITS_PER_UNIT,
355 positive specifies alignment boundary in bits.
357 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
358 alignment and ASLK_RECORD_PAD bit set if we should remember
359 extra space we allocated for alignment purposes. When we are
360 called from assign_stack_temp_for_type, it is not set so we don't
361 track the same stack slot in two independent lists.
363 We do not round to stack_boundary here. */
366 assign_stack_local_1 (machine_mode mode, HOST_WIDE_INT size,
367 int align, int kind)
369 rtx x, addr;
370 int bigend_correction = 0;
371 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
372 unsigned int alignment, alignment_in_bits;
374 if (align == 0)
376 alignment = get_stack_local_alignment (NULL, mode);
377 alignment /= BITS_PER_UNIT;
379 else if (align == -1)
381 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
382 size = CEIL_ROUND (size, alignment);
384 else if (align == -2)
385 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
386 else
387 alignment = align / BITS_PER_UNIT;
389 alignment_in_bits = alignment * BITS_PER_UNIT;
391 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
392 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
394 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
395 alignment = alignment_in_bits / BITS_PER_UNIT;
398 if (SUPPORTS_STACK_ALIGNMENT)
400 if (crtl->stack_alignment_estimated < alignment_in_bits)
402 if (!crtl->stack_realign_processed)
403 crtl->stack_alignment_estimated = alignment_in_bits;
404 else
406 /* If stack is realigned and stack alignment value
407 hasn't been finalized, it is OK not to increase
408 stack_alignment_estimated. The bigger alignment
409 requirement is recorded in stack_alignment_needed
410 below. */
411 gcc_assert (!crtl->stack_realign_finalized);
412 if (!crtl->stack_realign_needed)
414 /* It is OK to reduce the alignment as long as the
415 requested size is 0 or the estimated stack
416 alignment >= mode alignment. */
417 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
418 || size == 0
419 || (crtl->stack_alignment_estimated
420 >= GET_MODE_ALIGNMENT (mode)));
421 alignment_in_bits = crtl->stack_alignment_estimated;
422 alignment = alignment_in_bits / BITS_PER_UNIT;
428 if (crtl->stack_alignment_needed < alignment_in_bits)
429 crtl->stack_alignment_needed = alignment_in_bits;
430 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
431 crtl->max_used_stack_slot_alignment = alignment_in_bits;
433 if (mode != BLKmode || size != 0)
435 if (kind & ASLK_RECORD_PAD)
437 struct frame_space **psp;
439 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
441 struct frame_space *space = *psp;
442 if (!try_fit_stack_local (space->start, space->length, size,
443 alignment, &slot_offset))
444 continue;
445 *psp = space->next;
446 if (slot_offset > space->start)
447 add_frame_space (space->start, slot_offset);
448 if (slot_offset + size < space->start + space->length)
449 add_frame_space (slot_offset + size,
450 space->start + space->length);
451 goto found_space;
455 else if (!STACK_ALIGNMENT_NEEDED)
457 slot_offset = frame_offset;
458 goto found_space;
461 old_frame_offset = frame_offset;
463 if (FRAME_GROWS_DOWNWARD)
465 frame_offset -= size;
466 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
468 if (kind & ASLK_RECORD_PAD)
470 if (slot_offset > frame_offset)
471 add_frame_space (frame_offset, slot_offset);
472 if (slot_offset + size < old_frame_offset)
473 add_frame_space (slot_offset + size, old_frame_offset);
476 else
478 frame_offset += size;
479 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
481 if (kind & ASLK_RECORD_PAD)
483 if (slot_offset > old_frame_offset)
484 add_frame_space (old_frame_offset, slot_offset);
485 if (slot_offset + size < frame_offset)
486 add_frame_space (slot_offset + size, frame_offset);
490 found_space:
491 /* On a big-endian machine, if we are allocating more space than we will use,
492 use the least significant bytes of those that are allocated. */
493 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
494 bigend_correction = size - GET_MODE_SIZE (mode);
496 /* If we have already instantiated virtual registers, return the actual
497 address relative to the frame pointer. */
498 if (virtuals_instantiated)
499 addr = plus_constant (Pmode, frame_pointer_rtx,
500 trunc_int_for_mode
501 (slot_offset + bigend_correction
502 + STARTING_FRAME_OFFSET, Pmode));
503 else
504 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
505 trunc_int_for_mode
506 (slot_offset + bigend_correction,
507 Pmode));
509 x = gen_rtx_MEM (mode, addr);
510 set_mem_align (x, alignment_in_bits);
511 MEM_NOTRAP_P (x) = 1;
513 vec_safe_push (stack_slot_list, x);
515 if (frame_offset_overflow (frame_offset, current_function_decl))
516 frame_offset = 0;
518 return x;
521 /* Wrap up assign_stack_local_1 with last parameter as false. */
524 assign_stack_local (machine_mode mode, HOST_WIDE_INT size, int align)
526 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
529 /* In order to evaluate some expressions, such as function calls returning
530 structures in memory, we need to temporarily allocate stack locations.
531 We record each allocated temporary in the following structure.
533 Associated with each temporary slot is a nesting level. When we pop up
534 one level, all temporaries associated with the previous level are freed.
535 Normally, all temporaries are freed after the execution of the statement
536 in which they were created. However, if we are inside a ({...}) grouping,
537 the result may be in a temporary and hence must be preserved. If the
538 result could be in a temporary, we preserve it if we can determine which
539 one it is in. If we cannot determine which temporary may contain the
540 result, all temporaries are preserved. A temporary is preserved by
541 pretending it was allocated at the previous nesting level. */
543 struct GTY(()) temp_slot {
544 /* Points to next temporary slot. */
545 struct temp_slot *next;
546 /* Points to previous temporary slot. */
547 struct temp_slot *prev;
548 /* The rtx to used to reference the slot. */
549 rtx slot;
550 /* The size, in units, of the slot. */
551 HOST_WIDE_INT size;
552 /* The type of the object in the slot, or zero if it doesn't correspond
553 to a type. We use this to determine whether a slot can be reused.
554 It can be reused if objects of the type of the new slot will always
555 conflict with objects of the type of the old slot. */
556 tree type;
557 /* The alignment (in bits) of the slot. */
558 unsigned int align;
559 /* Nonzero if this temporary is currently in use. */
560 char in_use;
561 /* Nesting level at which this slot is being used. */
562 int level;
563 /* The offset of the slot from the frame_pointer, including extra space
564 for alignment. This info is for combine_temp_slots. */
565 HOST_WIDE_INT base_offset;
566 /* The size of the slot, including extra space for alignment. This
567 info is for combine_temp_slots. */
568 HOST_WIDE_INT full_size;
571 /* Entry for the below hash table. */
572 struct GTY((for_user)) temp_slot_address_entry {
573 hashval_t hash;
574 rtx address;
575 struct temp_slot *temp_slot;
578 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
580 static hashval_t hash (temp_slot_address_entry *);
581 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
584 /* A table of addresses that represent a stack slot. The table is a mapping
585 from address RTXen to a temp slot. */
586 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
587 static size_t n_temp_slots_in_use;
589 /* Removes temporary slot TEMP from LIST. */
591 static void
592 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
594 if (temp->next)
595 temp->next->prev = temp->prev;
596 if (temp->prev)
597 temp->prev->next = temp->next;
598 else
599 *list = temp->next;
601 temp->prev = temp->next = NULL;
604 /* Inserts temporary slot TEMP to LIST. */
606 static void
607 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
609 temp->next = *list;
610 if (*list)
611 (*list)->prev = temp;
612 temp->prev = NULL;
613 *list = temp;
616 /* Returns the list of used temp slots at LEVEL. */
618 static struct temp_slot **
619 temp_slots_at_level (int level)
621 if (level >= (int) vec_safe_length (used_temp_slots))
622 vec_safe_grow_cleared (used_temp_slots, level + 1);
624 return &(*used_temp_slots)[level];
627 /* Returns the maximal temporary slot level. */
629 static int
630 max_slot_level (void)
632 if (!used_temp_slots)
633 return -1;
635 return used_temp_slots->length () - 1;
638 /* Moves temporary slot TEMP to LEVEL. */
640 static void
641 move_slot_to_level (struct temp_slot *temp, int level)
643 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
644 insert_slot_to_list (temp, temp_slots_at_level (level));
645 temp->level = level;
648 /* Make temporary slot TEMP available. */
650 static void
651 make_slot_available (struct temp_slot *temp)
653 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
654 insert_slot_to_list (temp, &avail_temp_slots);
655 temp->in_use = 0;
656 temp->level = -1;
657 n_temp_slots_in_use--;
660 /* Compute the hash value for an address -> temp slot mapping.
661 The value is cached on the mapping entry. */
662 static hashval_t
663 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
665 int do_not_record = 0;
666 return hash_rtx (t->address, GET_MODE (t->address),
667 &do_not_record, NULL, false);
670 /* Return the hash value for an address -> temp slot mapping. */
671 hashval_t
672 temp_address_hasher::hash (temp_slot_address_entry *t)
674 return t->hash;
677 /* Compare two address -> temp slot mapping entries. */
678 bool
679 temp_address_hasher::equal (temp_slot_address_entry *t1,
680 temp_slot_address_entry *t2)
682 return exp_equiv_p (t1->address, t2->address, 0, true);
685 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
686 static void
687 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
689 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
690 t->address = address;
691 t->temp_slot = temp_slot;
692 t->hash = temp_slot_address_compute_hash (t);
693 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
696 /* Remove an address -> temp slot mapping entry if the temp slot is
697 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
699 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
701 const struct temp_slot_address_entry *t = *slot;
702 if (! t->temp_slot->in_use)
703 temp_slot_address_table->clear_slot (slot);
704 return 1;
707 /* Remove all mappings of addresses to unused temp slots. */
708 static void
709 remove_unused_temp_slot_addresses (void)
711 /* Use quicker clearing if there aren't any active temp slots. */
712 if (n_temp_slots_in_use)
713 temp_slot_address_table->traverse
714 <void *, remove_unused_temp_slot_addresses_1> (NULL);
715 else
716 temp_slot_address_table->empty ();
719 /* Find the temp slot corresponding to the object at address X. */
721 static struct temp_slot *
722 find_temp_slot_from_address (rtx x)
724 struct temp_slot *p;
725 struct temp_slot_address_entry tmp, *t;
727 /* First try the easy way:
728 See if X exists in the address -> temp slot mapping. */
729 tmp.address = x;
730 tmp.temp_slot = NULL;
731 tmp.hash = temp_slot_address_compute_hash (&tmp);
732 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
733 if (t)
734 return t->temp_slot;
736 /* If we have a sum involving a register, see if it points to a temp
737 slot. */
738 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
739 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
740 return p;
741 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
742 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
743 return p;
745 /* Last resort: Address is a virtual stack var address. */
746 if (GET_CODE (x) == PLUS
747 && XEXP (x, 0) == virtual_stack_vars_rtx
748 && CONST_INT_P (XEXP (x, 1)))
750 int i;
751 for (i = max_slot_level (); i >= 0; i--)
752 for (p = *temp_slots_at_level (i); p; p = p->next)
754 if (INTVAL (XEXP (x, 1)) >= p->base_offset
755 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
756 return p;
760 return NULL;
763 /* Allocate a temporary stack slot and record it for possible later
764 reuse.
766 MODE is the machine mode to be given to the returned rtx.
768 SIZE is the size in units of the space required. We do no rounding here
769 since assign_stack_local will do any required rounding.
771 TYPE is the type that will be used for the stack slot. */
774 assign_stack_temp_for_type (machine_mode mode, HOST_WIDE_INT size,
775 tree type)
777 unsigned int align;
778 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
779 rtx slot;
781 /* If SIZE is -1 it means that somebody tried to allocate a temporary
782 of a variable size. */
783 gcc_assert (size != -1);
785 align = get_stack_local_alignment (type, mode);
787 /* Try to find an available, already-allocated temporary of the proper
788 mode which meets the size and alignment requirements. Choose the
789 smallest one with the closest alignment.
791 If assign_stack_temp is called outside of the tree->rtl expansion,
792 we cannot reuse the stack slots (that may still refer to
793 VIRTUAL_STACK_VARS_REGNUM). */
794 if (!virtuals_instantiated)
796 for (p = avail_temp_slots; p; p = p->next)
798 if (p->align >= align && p->size >= size
799 && GET_MODE (p->slot) == mode
800 && objects_must_conflict_p (p->type, type)
801 && (best_p == 0 || best_p->size > p->size
802 || (best_p->size == p->size && best_p->align > p->align)))
804 if (p->align == align && p->size == size)
806 selected = p;
807 cut_slot_from_list (selected, &avail_temp_slots);
808 best_p = 0;
809 break;
811 best_p = p;
816 /* Make our best, if any, the one to use. */
817 if (best_p)
819 selected = best_p;
820 cut_slot_from_list (selected, &avail_temp_slots);
822 /* If there are enough aligned bytes left over, make them into a new
823 temp_slot so that the extra bytes don't get wasted. Do this only
824 for BLKmode slots, so that we can be sure of the alignment. */
825 if (GET_MODE (best_p->slot) == BLKmode)
827 int alignment = best_p->align / BITS_PER_UNIT;
828 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
830 if (best_p->size - rounded_size >= alignment)
832 p = ggc_alloc<temp_slot> ();
833 p->in_use = 0;
834 p->size = best_p->size - rounded_size;
835 p->base_offset = best_p->base_offset + rounded_size;
836 p->full_size = best_p->full_size - rounded_size;
837 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
838 p->align = best_p->align;
839 p->type = best_p->type;
840 insert_slot_to_list (p, &avail_temp_slots);
842 vec_safe_push (stack_slot_list, p->slot);
844 best_p->size = rounded_size;
845 best_p->full_size = rounded_size;
850 /* If we still didn't find one, make a new temporary. */
851 if (selected == 0)
853 HOST_WIDE_INT frame_offset_old = frame_offset;
855 p = ggc_alloc<temp_slot> ();
857 /* We are passing an explicit alignment request to assign_stack_local.
858 One side effect of that is assign_stack_local will not round SIZE
859 to ensure the frame offset remains suitably aligned.
861 So for requests which depended on the rounding of SIZE, we go ahead
862 and round it now. We also make sure ALIGNMENT is at least
863 BIGGEST_ALIGNMENT. */
864 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
865 p->slot = assign_stack_local_1 (mode,
866 (mode == BLKmode
867 ? CEIL_ROUND (size,
868 (int) align
869 / BITS_PER_UNIT)
870 : size),
871 align, 0);
873 p->align = align;
875 /* The following slot size computation is necessary because we don't
876 know the actual size of the temporary slot until assign_stack_local
877 has performed all the frame alignment and size rounding for the
878 requested temporary. Note that extra space added for alignment
879 can be either above or below this stack slot depending on which
880 way the frame grows. We include the extra space if and only if it
881 is above this slot. */
882 if (FRAME_GROWS_DOWNWARD)
883 p->size = frame_offset_old - frame_offset;
884 else
885 p->size = size;
887 /* Now define the fields used by combine_temp_slots. */
888 if (FRAME_GROWS_DOWNWARD)
890 p->base_offset = frame_offset;
891 p->full_size = frame_offset_old - frame_offset;
893 else
895 p->base_offset = frame_offset_old;
896 p->full_size = frame_offset - frame_offset_old;
899 selected = p;
902 p = selected;
903 p->in_use = 1;
904 p->type = type;
905 p->level = temp_slot_level;
906 n_temp_slots_in_use++;
908 pp = temp_slots_at_level (p->level);
909 insert_slot_to_list (p, pp);
910 insert_temp_slot_address (XEXP (p->slot, 0), p);
912 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
913 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
914 vec_safe_push (stack_slot_list, slot);
916 /* If we know the alias set for the memory that will be used, use
917 it. If there's no TYPE, then we don't know anything about the
918 alias set for the memory. */
919 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
920 set_mem_align (slot, align);
922 /* If a type is specified, set the relevant flags. */
923 if (type != 0)
924 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
925 MEM_NOTRAP_P (slot) = 1;
927 return slot;
930 /* Allocate a temporary stack slot and record it for possible later
931 reuse. First two arguments are same as in preceding function. */
934 assign_stack_temp (machine_mode mode, HOST_WIDE_INT size)
936 return assign_stack_temp_for_type (mode, size, NULL_TREE);
939 /* Assign a temporary.
940 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
941 and so that should be used in error messages. In either case, we
942 allocate of the given type.
943 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
944 it is 0 if a register is OK.
945 DONT_PROMOTE is 1 if we should not promote values in register
946 to wider modes. */
949 assign_temp (tree type_or_decl, int memory_required,
950 int dont_promote ATTRIBUTE_UNUSED)
952 tree type, decl;
953 machine_mode mode;
954 #ifdef PROMOTE_MODE
955 int unsignedp;
956 #endif
958 if (DECL_P (type_or_decl))
959 decl = type_or_decl, type = TREE_TYPE (decl);
960 else
961 decl = NULL, type = type_or_decl;
963 mode = TYPE_MODE (type);
964 #ifdef PROMOTE_MODE
965 unsignedp = TYPE_UNSIGNED (type);
966 #endif
968 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
969 end. See also create_tmp_var for the gimplification-time check. */
970 gcc_assert (!TREE_ADDRESSABLE (type) && COMPLETE_TYPE_P (type));
972 if (mode == BLKmode || memory_required)
974 HOST_WIDE_INT size = int_size_in_bytes (type);
975 rtx tmp;
977 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
978 problems with allocating the stack space. */
979 if (size == 0)
980 size = 1;
982 /* Unfortunately, we don't yet know how to allocate variable-sized
983 temporaries. However, sometimes we can find a fixed upper limit on
984 the size, so try that instead. */
985 else if (size == -1)
986 size = max_int_size_in_bytes (type);
988 /* The size of the temporary may be too large to fit into an integer. */
989 /* ??? Not sure this should happen except for user silliness, so limit
990 this to things that aren't compiler-generated temporaries. The
991 rest of the time we'll die in assign_stack_temp_for_type. */
992 if (decl && size == -1
993 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
995 error ("size of variable %q+D is too large", decl);
996 size = 1;
999 tmp = assign_stack_temp_for_type (mode, size, type);
1000 return tmp;
1003 #ifdef PROMOTE_MODE
1004 if (! dont_promote)
1005 mode = promote_mode (type, mode, &unsignedp);
1006 #endif
1008 return gen_reg_rtx (mode);
1011 /* Combine temporary stack slots which are adjacent on the stack.
1013 This allows for better use of already allocated stack space. This is only
1014 done for BLKmode slots because we can be sure that we won't have alignment
1015 problems in this case. */
1017 static void
1018 combine_temp_slots (void)
1020 struct temp_slot *p, *q, *next, *next_q;
1021 int num_slots;
1023 /* We can't combine slots, because the information about which slot
1024 is in which alias set will be lost. */
1025 if (flag_strict_aliasing)
1026 return;
1028 /* If there are a lot of temp slots, don't do anything unless
1029 high levels of optimization. */
1030 if (! flag_expensive_optimizations)
1031 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1032 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1033 return;
1035 for (p = avail_temp_slots; p; p = next)
1037 int delete_p = 0;
1039 next = p->next;
1041 if (GET_MODE (p->slot) != BLKmode)
1042 continue;
1044 for (q = p->next; q; q = next_q)
1046 int delete_q = 0;
1048 next_q = q->next;
1050 if (GET_MODE (q->slot) != BLKmode)
1051 continue;
1053 if (p->base_offset + p->full_size == q->base_offset)
1055 /* Q comes after P; combine Q into P. */
1056 p->size += q->size;
1057 p->full_size += q->full_size;
1058 delete_q = 1;
1060 else if (q->base_offset + q->full_size == p->base_offset)
1062 /* P comes after Q; combine P into Q. */
1063 q->size += p->size;
1064 q->full_size += p->full_size;
1065 delete_p = 1;
1066 break;
1068 if (delete_q)
1069 cut_slot_from_list (q, &avail_temp_slots);
1072 /* Either delete P or advance past it. */
1073 if (delete_p)
1074 cut_slot_from_list (p, &avail_temp_slots);
1078 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1079 slot that previously was known by OLD_RTX. */
1081 void
1082 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1084 struct temp_slot *p;
1086 if (rtx_equal_p (old_rtx, new_rtx))
1087 return;
1089 p = find_temp_slot_from_address (old_rtx);
1091 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1092 NEW_RTX is a register, see if one operand of the PLUS is a
1093 temporary location. If so, NEW_RTX points into it. Otherwise,
1094 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1095 in common between them. If so, try a recursive call on those
1096 values. */
1097 if (p == 0)
1099 if (GET_CODE (old_rtx) != PLUS)
1100 return;
1102 if (REG_P (new_rtx))
1104 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1105 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1106 return;
1108 else if (GET_CODE (new_rtx) != PLUS)
1109 return;
1111 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1112 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1113 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1114 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1115 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1116 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1117 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1118 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1120 return;
1123 /* Otherwise add an alias for the temp's address. */
1124 insert_temp_slot_address (new_rtx, p);
1127 /* If X could be a reference to a temporary slot, mark that slot as
1128 belonging to the to one level higher than the current level. If X
1129 matched one of our slots, just mark that one. Otherwise, we can't
1130 easily predict which it is, so upgrade all of them.
1132 This is called when an ({...}) construct occurs and a statement
1133 returns a value in memory. */
1135 void
1136 preserve_temp_slots (rtx x)
1138 struct temp_slot *p = 0, *next;
1140 if (x == 0)
1141 return;
1143 /* If X is a register that is being used as a pointer, see if we have
1144 a temporary slot we know it points to. */
1145 if (REG_P (x) && REG_POINTER (x))
1146 p = find_temp_slot_from_address (x);
1148 /* If X is not in memory or is at a constant address, it cannot be in
1149 a temporary slot. */
1150 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1151 return;
1153 /* First see if we can find a match. */
1154 if (p == 0)
1155 p = find_temp_slot_from_address (XEXP (x, 0));
1157 if (p != 0)
1159 if (p->level == temp_slot_level)
1160 move_slot_to_level (p, temp_slot_level - 1);
1161 return;
1164 /* Otherwise, preserve all non-kept slots at this level. */
1165 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1167 next = p->next;
1168 move_slot_to_level (p, temp_slot_level - 1);
1172 /* Free all temporaries used so far. This is normally called at the
1173 end of generating code for a statement. */
1175 void
1176 free_temp_slots (void)
1178 struct temp_slot *p, *next;
1179 bool some_available = false;
1181 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1183 next = p->next;
1184 make_slot_available (p);
1185 some_available = true;
1188 if (some_available)
1190 remove_unused_temp_slot_addresses ();
1191 combine_temp_slots ();
1195 /* Push deeper into the nesting level for stack temporaries. */
1197 void
1198 push_temp_slots (void)
1200 temp_slot_level++;
1203 /* Pop a temporary nesting level. All slots in use in the current level
1204 are freed. */
1206 void
1207 pop_temp_slots (void)
1209 free_temp_slots ();
1210 temp_slot_level--;
1213 /* Initialize temporary slots. */
1215 void
1216 init_temp_slots (void)
1218 /* We have not allocated any temporaries yet. */
1219 avail_temp_slots = 0;
1220 vec_alloc (used_temp_slots, 0);
1221 temp_slot_level = 0;
1222 n_temp_slots_in_use = 0;
1224 /* Set up the table to map addresses to temp slots. */
1225 if (! temp_slot_address_table)
1226 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1227 else
1228 temp_slot_address_table->empty ();
1231 /* Functions and data structures to keep track of the values hard regs
1232 had at the start of the function. */
1234 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1235 and has_hard_reg_initial_val.. */
1236 struct GTY(()) initial_value_pair {
1237 rtx hard_reg;
1238 rtx pseudo;
1240 /* ??? This could be a VEC but there is currently no way to define an
1241 opaque VEC type. This could be worked around by defining struct
1242 initial_value_pair in function.h. */
1243 struct GTY(()) initial_value_struct {
1244 int num_entries;
1245 int max_entries;
1246 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1249 /* If a pseudo represents an initial hard reg (or expression), return
1250 it, else return NULL_RTX. */
1253 get_hard_reg_initial_reg (rtx reg)
1255 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1256 int i;
1258 if (ivs == 0)
1259 return NULL_RTX;
1261 for (i = 0; i < ivs->num_entries; i++)
1262 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1263 return ivs->entries[i].hard_reg;
1265 return NULL_RTX;
1268 /* Make sure that there's a pseudo register of mode MODE that stores the
1269 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1272 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1274 struct initial_value_struct *ivs;
1275 rtx rv;
1277 rv = has_hard_reg_initial_val (mode, regno);
1278 if (rv)
1279 return rv;
1281 ivs = crtl->hard_reg_initial_vals;
1282 if (ivs == 0)
1284 ivs = ggc_alloc<initial_value_struct> ();
1285 ivs->num_entries = 0;
1286 ivs->max_entries = 5;
1287 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1288 crtl->hard_reg_initial_vals = ivs;
1291 if (ivs->num_entries >= ivs->max_entries)
1293 ivs->max_entries += 5;
1294 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1295 ivs->max_entries);
1298 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1299 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1301 return ivs->entries[ivs->num_entries++].pseudo;
1304 /* See if get_hard_reg_initial_val has been used to create a pseudo
1305 for the initial value of hard register REGNO in mode MODE. Return
1306 the associated pseudo if so, otherwise return NULL. */
1309 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1311 struct initial_value_struct *ivs;
1312 int i;
1314 ivs = crtl->hard_reg_initial_vals;
1315 if (ivs != 0)
1316 for (i = 0; i < ivs->num_entries; i++)
1317 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1318 && REGNO (ivs->entries[i].hard_reg) == regno)
1319 return ivs->entries[i].pseudo;
1321 return NULL_RTX;
1324 unsigned int
1325 emit_initial_value_sets (void)
1327 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1328 int i;
1329 rtx_insn *seq;
1331 if (ivs == 0)
1332 return 0;
1334 start_sequence ();
1335 for (i = 0; i < ivs->num_entries; i++)
1336 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1337 seq = get_insns ();
1338 end_sequence ();
1340 emit_insn_at_entry (seq);
1341 return 0;
1344 /* Return the hardreg-pseudoreg initial values pair entry I and
1345 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1346 bool
1347 initial_value_entry (int i, rtx *hreg, rtx *preg)
1349 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1350 if (!ivs || i >= ivs->num_entries)
1351 return false;
1353 *hreg = ivs->entries[i].hard_reg;
1354 *preg = ivs->entries[i].pseudo;
1355 return true;
1358 /* These routines are responsible for converting virtual register references
1359 to the actual hard register references once RTL generation is complete.
1361 The following four variables are used for communication between the
1362 routines. They contain the offsets of the virtual registers from their
1363 respective hard registers. */
1365 static int in_arg_offset;
1366 static int var_offset;
1367 static int dynamic_offset;
1368 static int out_arg_offset;
1369 static int cfa_offset;
1371 /* In most machines, the stack pointer register is equivalent to the bottom
1372 of the stack. */
1374 #ifndef STACK_POINTER_OFFSET
1375 #define STACK_POINTER_OFFSET 0
1376 #endif
1378 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1379 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1380 #endif
1382 /* If not defined, pick an appropriate default for the offset of dynamically
1383 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1384 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1386 #ifndef STACK_DYNAMIC_OFFSET
1388 /* The bottom of the stack points to the actual arguments. If
1389 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1390 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1391 stack space for register parameters is not pushed by the caller, but
1392 rather part of the fixed stack areas and hence not included in
1393 `crtl->outgoing_args_size'. Nevertheless, we must allow
1394 for it when allocating stack dynamic objects. */
1396 #ifdef INCOMING_REG_PARM_STACK_SPACE
1397 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1398 ((ACCUMULATE_OUTGOING_ARGS \
1399 ? (crtl->outgoing_args_size \
1400 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1401 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1402 : 0) + (STACK_POINTER_OFFSET))
1403 #else
1404 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1405 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1406 + (STACK_POINTER_OFFSET))
1407 #endif
1408 #endif
1411 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1412 is a virtual register, return the equivalent hard register and set the
1413 offset indirectly through the pointer. Otherwise, return 0. */
1415 static rtx
1416 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1418 rtx new_rtx;
1419 HOST_WIDE_INT offset;
1421 if (x == virtual_incoming_args_rtx)
1423 if (stack_realign_drap)
1425 /* Replace virtual_incoming_args_rtx with internal arg
1426 pointer if DRAP is used to realign stack. */
1427 new_rtx = crtl->args.internal_arg_pointer;
1428 offset = 0;
1430 else
1431 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1433 else if (x == virtual_stack_vars_rtx)
1434 new_rtx = frame_pointer_rtx, offset = var_offset;
1435 else if (x == virtual_stack_dynamic_rtx)
1436 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1437 else if (x == virtual_outgoing_args_rtx)
1438 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1439 else if (x == virtual_cfa_rtx)
1441 #ifdef FRAME_POINTER_CFA_OFFSET
1442 new_rtx = frame_pointer_rtx;
1443 #else
1444 new_rtx = arg_pointer_rtx;
1445 #endif
1446 offset = cfa_offset;
1448 else if (x == virtual_preferred_stack_boundary_rtx)
1450 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1451 offset = 0;
1453 else
1454 return NULL_RTX;
1456 *poffset = offset;
1457 return new_rtx;
1460 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1461 registers present inside of *LOC. The expression is simplified,
1462 as much as possible, but is not to be considered "valid" in any sense
1463 implied by the target. Return true if any change is made. */
1465 static bool
1466 instantiate_virtual_regs_in_rtx (rtx *loc)
1468 if (!*loc)
1469 return false;
1470 bool changed = false;
1471 subrtx_ptr_iterator::array_type array;
1472 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1474 rtx *loc = *iter;
1475 if (rtx x = *loc)
1477 rtx new_rtx;
1478 HOST_WIDE_INT offset;
1479 switch (GET_CODE (x))
1481 case REG:
1482 new_rtx = instantiate_new_reg (x, &offset);
1483 if (new_rtx)
1485 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1486 changed = true;
1488 iter.skip_subrtxes ();
1489 break;
1491 case PLUS:
1492 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1493 if (new_rtx)
1495 XEXP (x, 0) = new_rtx;
1496 *loc = plus_constant (GET_MODE (x), x, offset, true);
1497 changed = true;
1498 iter.skip_subrtxes ();
1499 break;
1502 /* FIXME -- from old code */
1503 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1504 we can commute the PLUS and SUBREG because pointers into the
1505 frame are well-behaved. */
1506 break;
1508 default:
1509 break;
1513 return changed;
1516 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1517 matches the predicate for insn CODE operand OPERAND. */
1519 static int
1520 safe_insn_predicate (int code, int operand, rtx x)
1522 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1525 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1526 registers present inside of insn. The result will be a valid insn. */
1528 static void
1529 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1531 HOST_WIDE_INT offset;
1532 int insn_code, i;
1533 bool any_change = false;
1534 rtx set, new_rtx, x;
1535 rtx_insn *seq;
1537 /* There are some special cases to be handled first. */
1538 set = single_set (insn);
1539 if (set)
1541 /* We're allowed to assign to a virtual register. This is interpreted
1542 to mean that the underlying register gets assigned the inverse
1543 transformation. This is used, for example, in the handling of
1544 non-local gotos. */
1545 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1546 if (new_rtx)
1548 start_sequence ();
1550 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1551 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1552 gen_int_mode (-offset, GET_MODE (new_rtx)));
1553 x = force_operand (x, new_rtx);
1554 if (x != new_rtx)
1555 emit_move_insn (new_rtx, x);
1557 seq = get_insns ();
1558 end_sequence ();
1560 emit_insn_before (seq, insn);
1561 delete_insn (insn);
1562 return;
1565 /* Handle a straight copy from a virtual register by generating a
1566 new add insn. The difference between this and falling through
1567 to the generic case is avoiding a new pseudo and eliminating a
1568 move insn in the initial rtl stream. */
1569 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1570 if (new_rtx && offset != 0
1571 && REG_P (SET_DEST (set))
1572 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1574 start_sequence ();
1576 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1577 gen_int_mode (offset,
1578 GET_MODE (SET_DEST (set))),
1579 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1580 if (x != SET_DEST (set))
1581 emit_move_insn (SET_DEST (set), x);
1583 seq = get_insns ();
1584 end_sequence ();
1586 emit_insn_before (seq, insn);
1587 delete_insn (insn);
1588 return;
1591 extract_insn (insn);
1592 insn_code = INSN_CODE (insn);
1594 /* Handle a plus involving a virtual register by determining if the
1595 operands remain valid if they're modified in place. */
1596 if (GET_CODE (SET_SRC (set)) == PLUS
1597 && recog_data.n_operands >= 3
1598 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1599 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1600 && CONST_INT_P (recog_data.operand[2])
1601 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1603 offset += INTVAL (recog_data.operand[2]);
1605 /* If the sum is zero, then replace with a plain move. */
1606 if (offset == 0
1607 && REG_P (SET_DEST (set))
1608 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1610 start_sequence ();
1611 emit_move_insn (SET_DEST (set), new_rtx);
1612 seq = get_insns ();
1613 end_sequence ();
1615 emit_insn_before (seq, insn);
1616 delete_insn (insn);
1617 return;
1620 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1622 /* Using validate_change and apply_change_group here leaves
1623 recog_data in an invalid state. Since we know exactly what
1624 we want to check, do those two by hand. */
1625 if (safe_insn_predicate (insn_code, 1, new_rtx)
1626 && safe_insn_predicate (insn_code, 2, x))
1628 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1629 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1630 any_change = true;
1632 /* Fall through into the regular operand fixup loop in
1633 order to take care of operands other than 1 and 2. */
1637 else
1639 extract_insn (insn);
1640 insn_code = INSN_CODE (insn);
1643 /* In the general case, we expect virtual registers to appear only in
1644 operands, and then only as either bare registers or inside memories. */
1645 for (i = 0; i < recog_data.n_operands; ++i)
1647 x = recog_data.operand[i];
1648 switch (GET_CODE (x))
1650 case MEM:
1652 rtx addr = XEXP (x, 0);
1654 if (!instantiate_virtual_regs_in_rtx (&addr))
1655 continue;
1657 start_sequence ();
1658 x = replace_equiv_address (x, addr, true);
1659 /* It may happen that the address with the virtual reg
1660 was valid (e.g. based on the virtual stack reg, which might
1661 be acceptable to the predicates with all offsets), whereas
1662 the address now isn't anymore, for instance when the address
1663 is still offsetted, but the base reg isn't virtual-stack-reg
1664 anymore. Below we would do a force_reg on the whole operand,
1665 but this insn might actually only accept memory. Hence,
1666 before doing that last resort, try to reload the address into
1667 a register, so this operand stays a MEM. */
1668 if (!safe_insn_predicate (insn_code, i, x))
1670 addr = force_reg (GET_MODE (addr), addr);
1671 x = replace_equiv_address (x, addr, true);
1673 seq = get_insns ();
1674 end_sequence ();
1675 if (seq)
1676 emit_insn_before (seq, insn);
1678 break;
1680 case REG:
1681 new_rtx = instantiate_new_reg (x, &offset);
1682 if (new_rtx == NULL)
1683 continue;
1684 if (offset == 0)
1685 x = new_rtx;
1686 else
1688 start_sequence ();
1690 /* Careful, special mode predicates may have stuff in
1691 insn_data[insn_code].operand[i].mode that isn't useful
1692 to us for computing a new value. */
1693 /* ??? Recognize address_operand and/or "p" constraints
1694 to see if (plus new offset) is a valid before we put
1695 this through expand_simple_binop. */
1696 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1697 gen_int_mode (offset, GET_MODE (x)),
1698 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1699 seq = get_insns ();
1700 end_sequence ();
1701 emit_insn_before (seq, insn);
1703 break;
1705 case SUBREG:
1706 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1707 if (new_rtx == NULL)
1708 continue;
1709 if (offset != 0)
1711 start_sequence ();
1712 new_rtx = expand_simple_binop
1713 (GET_MODE (new_rtx), PLUS, new_rtx,
1714 gen_int_mode (offset, GET_MODE (new_rtx)),
1715 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1716 seq = get_insns ();
1717 end_sequence ();
1718 emit_insn_before (seq, insn);
1720 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1721 GET_MODE (new_rtx), SUBREG_BYTE (x));
1722 gcc_assert (x);
1723 break;
1725 default:
1726 continue;
1729 /* At this point, X contains the new value for the operand.
1730 Validate the new value vs the insn predicate. Note that
1731 asm insns will have insn_code -1 here. */
1732 if (!safe_insn_predicate (insn_code, i, x))
1734 start_sequence ();
1735 if (REG_P (x))
1737 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1738 x = copy_to_reg (x);
1740 else
1741 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1742 seq = get_insns ();
1743 end_sequence ();
1744 if (seq)
1745 emit_insn_before (seq, insn);
1748 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1749 any_change = true;
1752 if (any_change)
1754 /* Propagate operand changes into the duplicates. */
1755 for (i = 0; i < recog_data.n_dups; ++i)
1756 *recog_data.dup_loc[i]
1757 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1759 /* Force re-recognition of the instruction for validation. */
1760 INSN_CODE (insn) = -1;
1763 if (asm_noperands (PATTERN (insn)) >= 0)
1765 if (!check_asm_operands (PATTERN (insn)))
1767 error_for_asm (insn, "impossible constraint in %<asm%>");
1768 /* For asm goto, instead of fixing up all the edges
1769 just clear the template and clear input operands
1770 (asm goto doesn't have any output operands). */
1771 if (JUMP_P (insn))
1773 rtx asm_op = extract_asm_operands (PATTERN (insn));
1774 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1775 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1776 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1778 else
1779 delete_insn (insn);
1782 else
1784 if (recog_memoized (insn) < 0)
1785 fatal_insn_not_found (insn);
1789 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1790 do any instantiation required. */
1792 void
1793 instantiate_decl_rtl (rtx x)
1795 rtx addr;
1797 if (x == 0)
1798 return;
1800 /* If this is a CONCAT, recurse for the pieces. */
1801 if (GET_CODE (x) == CONCAT)
1803 instantiate_decl_rtl (XEXP (x, 0));
1804 instantiate_decl_rtl (XEXP (x, 1));
1805 return;
1808 /* If this is not a MEM, no need to do anything. Similarly if the
1809 address is a constant or a register that is not a virtual register. */
1810 if (!MEM_P (x))
1811 return;
1813 addr = XEXP (x, 0);
1814 if (CONSTANT_P (addr)
1815 || (REG_P (addr)
1816 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1817 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1818 return;
1820 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1823 /* Helper for instantiate_decls called via walk_tree: Process all decls
1824 in the given DECL_VALUE_EXPR. */
1826 static tree
1827 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1829 tree t = *tp;
1830 if (! EXPR_P (t))
1832 *walk_subtrees = 0;
1833 if (DECL_P (t))
1835 if (DECL_RTL_SET_P (t))
1836 instantiate_decl_rtl (DECL_RTL (t));
1837 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1838 && DECL_INCOMING_RTL (t))
1839 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1840 if ((VAR_P (t) || TREE_CODE (t) == RESULT_DECL)
1841 && DECL_HAS_VALUE_EXPR_P (t))
1843 tree v = DECL_VALUE_EXPR (t);
1844 walk_tree (&v, instantiate_expr, NULL, NULL);
1848 return NULL;
1851 /* Subroutine of instantiate_decls: Process all decls in the given
1852 BLOCK node and all its subblocks. */
1854 static void
1855 instantiate_decls_1 (tree let)
1857 tree t;
1859 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1861 if (DECL_RTL_SET_P (t))
1862 instantiate_decl_rtl (DECL_RTL (t));
1863 if (VAR_P (t) && DECL_HAS_VALUE_EXPR_P (t))
1865 tree v = DECL_VALUE_EXPR (t);
1866 walk_tree (&v, instantiate_expr, NULL, NULL);
1870 /* Process all subblocks. */
1871 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1872 instantiate_decls_1 (t);
1875 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1876 all virtual registers in their DECL_RTL's. */
1878 static void
1879 instantiate_decls (tree fndecl)
1881 tree decl;
1882 unsigned ix;
1884 /* Process all parameters of the function. */
1885 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1887 instantiate_decl_rtl (DECL_RTL (decl));
1888 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1889 if (DECL_HAS_VALUE_EXPR_P (decl))
1891 tree v = DECL_VALUE_EXPR (decl);
1892 walk_tree (&v, instantiate_expr, NULL, NULL);
1896 if ((decl = DECL_RESULT (fndecl))
1897 && TREE_CODE (decl) == RESULT_DECL)
1899 if (DECL_RTL_SET_P (decl))
1900 instantiate_decl_rtl (DECL_RTL (decl));
1901 if (DECL_HAS_VALUE_EXPR_P (decl))
1903 tree v = DECL_VALUE_EXPR (decl);
1904 walk_tree (&v, instantiate_expr, NULL, NULL);
1908 /* Process the saved static chain if it exists. */
1909 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1910 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1911 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1913 /* Now process all variables defined in the function or its subblocks. */
1914 if (DECL_INITIAL (fndecl))
1915 instantiate_decls_1 (DECL_INITIAL (fndecl));
1917 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1918 if (DECL_RTL_SET_P (decl))
1919 instantiate_decl_rtl (DECL_RTL (decl));
1920 vec_free (cfun->local_decls);
1923 /* Pass through the INSNS of function FNDECL and convert virtual register
1924 references to hard register references. */
1926 static unsigned int
1927 instantiate_virtual_regs (void)
1929 rtx_insn *insn;
1931 /* Compute the offsets to use for this function. */
1932 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1933 var_offset = STARTING_FRAME_OFFSET;
1934 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1935 out_arg_offset = STACK_POINTER_OFFSET;
1936 #ifdef FRAME_POINTER_CFA_OFFSET
1937 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1938 #else
1939 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1940 #endif
1942 /* Initialize recognition, indicating that volatile is OK. */
1943 init_recog ();
1945 /* Scan through all the insns, instantiating every virtual register still
1946 present. */
1947 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1948 if (INSN_P (insn))
1950 /* These patterns in the instruction stream can never be recognized.
1951 Fortunately, they shouldn't contain virtual registers either. */
1952 if (GET_CODE (PATTERN (insn)) == USE
1953 || GET_CODE (PATTERN (insn)) == CLOBBER
1954 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1955 continue;
1956 else if (DEBUG_INSN_P (insn))
1957 instantiate_virtual_regs_in_rtx (&INSN_VAR_LOCATION (insn));
1958 else
1959 instantiate_virtual_regs_in_insn (insn);
1961 if (insn->deleted ())
1962 continue;
1964 instantiate_virtual_regs_in_rtx (&REG_NOTES (insn));
1966 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1967 if (CALL_P (insn))
1968 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1971 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1972 instantiate_decls (current_function_decl);
1974 targetm.instantiate_decls ();
1976 /* Indicate that, from now on, assign_stack_local should use
1977 frame_pointer_rtx. */
1978 virtuals_instantiated = 1;
1980 return 0;
1983 namespace {
1985 const pass_data pass_data_instantiate_virtual_regs =
1987 RTL_PASS, /* type */
1988 "vregs", /* name */
1989 OPTGROUP_NONE, /* optinfo_flags */
1990 TV_NONE, /* tv_id */
1991 0, /* properties_required */
1992 0, /* properties_provided */
1993 0, /* properties_destroyed */
1994 0, /* todo_flags_start */
1995 0, /* todo_flags_finish */
1998 class pass_instantiate_virtual_regs : public rtl_opt_pass
2000 public:
2001 pass_instantiate_virtual_regs (gcc::context *ctxt)
2002 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2005 /* opt_pass methods: */
2006 virtual unsigned int execute (function *)
2008 return instantiate_virtual_regs ();
2011 }; // class pass_instantiate_virtual_regs
2013 } // anon namespace
2015 rtl_opt_pass *
2016 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2018 return new pass_instantiate_virtual_regs (ctxt);
2022 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2023 This means a type for which function calls must pass an address to the
2024 function or get an address back from the function.
2025 EXP may be a type node or an expression (whose type is tested). */
2028 aggregate_value_p (const_tree exp, const_tree fntype)
2030 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2031 int i, regno, nregs;
2032 rtx reg;
2034 if (fntype)
2035 switch (TREE_CODE (fntype))
2037 case CALL_EXPR:
2039 tree fndecl = get_callee_fndecl (fntype);
2040 if (fndecl)
2041 fntype = TREE_TYPE (fndecl);
2042 else if (CALL_EXPR_FN (fntype))
2043 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2044 else
2045 /* For internal functions, assume nothing needs to be
2046 returned in memory. */
2047 return 0;
2049 break;
2050 case FUNCTION_DECL:
2051 fntype = TREE_TYPE (fntype);
2052 break;
2053 case FUNCTION_TYPE:
2054 case METHOD_TYPE:
2055 break;
2056 case IDENTIFIER_NODE:
2057 fntype = NULL_TREE;
2058 break;
2059 default:
2060 /* We don't expect other tree types here. */
2061 gcc_unreachable ();
2064 if (VOID_TYPE_P (type))
2065 return 0;
2067 /* If a record should be passed the same as its first (and only) member
2068 don't pass it as an aggregate. */
2069 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2070 return aggregate_value_p (first_field (type), fntype);
2072 /* If the front end has decided that this needs to be passed by
2073 reference, do so. */
2074 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2075 && DECL_BY_REFERENCE (exp))
2076 return 1;
2078 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2079 if (fntype && TREE_ADDRESSABLE (fntype))
2080 return 1;
2082 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2083 and thus can't be returned in registers. */
2084 if (TREE_ADDRESSABLE (type))
2085 return 1;
2087 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2088 return 1;
2090 if (targetm.calls.return_in_memory (type, fntype))
2091 return 1;
2093 /* Make sure we have suitable call-clobbered regs to return
2094 the value in; if not, we must return it in memory. */
2095 reg = hard_function_value (type, 0, fntype, 0);
2097 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2098 it is OK. */
2099 if (!REG_P (reg))
2100 return 0;
2102 regno = REGNO (reg);
2103 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
2104 for (i = 0; i < nregs; i++)
2105 if (! call_used_regs[regno + i])
2106 return 1;
2108 return 0;
2111 /* Return true if we should assign DECL a pseudo register; false if it
2112 should live on the local stack. */
2114 bool
2115 use_register_for_decl (const_tree decl)
2117 if (TREE_CODE (decl) == SSA_NAME)
2119 /* We often try to use the SSA_NAME, instead of its underlying
2120 decl, to get type information and guide decisions, to avoid
2121 differences of behavior between anonymous and named
2122 variables, but in this one case we have to go for the actual
2123 variable if there is one. The main reason is that, at least
2124 at -O0, we want to place user variables on the stack, but we
2125 don't mind using pseudos for anonymous or ignored temps.
2126 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2127 should go in pseudos, whereas their corresponding variables
2128 might have to go on the stack. So, disregarding the decl
2129 here would negatively impact debug info at -O0, enable
2130 coalescing between SSA_NAMEs that ought to get different
2131 stack/pseudo assignments, and get the incoming argument
2132 processing thoroughly confused by PARM_DECLs expected to live
2133 in stack slots but assigned to pseudos. */
2134 if (!SSA_NAME_VAR (decl))
2135 return TYPE_MODE (TREE_TYPE (decl)) != BLKmode
2136 && !(flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)));
2138 decl = SSA_NAME_VAR (decl);
2141 /* Honor volatile. */
2142 if (TREE_SIDE_EFFECTS (decl))
2143 return false;
2145 /* Honor addressability. */
2146 if (TREE_ADDRESSABLE (decl))
2147 return false;
2149 /* RESULT_DECLs are a bit special in that they're assigned without
2150 regard to use_register_for_decl, but we generally only store in
2151 them. If we coalesce their SSA NAMEs, we'd better return a
2152 result that matches the assignment in expand_function_start. */
2153 if (TREE_CODE (decl) == RESULT_DECL)
2155 /* If it's not an aggregate, we're going to use a REG or a
2156 PARALLEL containing a REG. */
2157 if (!aggregate_value_p (decl, current_function_decl))
2158 return true;
2160 /* If expand_function_start determines the return value, we'll
2161 use MEM if it's not by reference. */
2162 if (cfun->returns_pcc_struct
2163 || (targetm.calls.struct_value_rtx
2164 (TREE_TYPE (current_function_decl), 1)))
2165 return DECL_BY_REFERENCE (decl);
2167 /* Otherwise, we're taking an extra all.function_result_decl
2168 argument. It's set up in assign_parms_augmented_arg_list,
2169 under the (negated) conditions above, and then it's used to
2170 set up the RESULT_DECL rtl in assign_params, after looping
2171 over all parameters. Now, if the RESULT_DECL is not by
2172 reference, we'll use a MEM either way. */
2173 if (!DECL_BY_REFERENCE (decl))
2174 return false;
2176 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2177 the function_result_decl's assignment. Since it's a pointer,
2178 we can short-circuit a number of the tests below, and we must
2179 duplicat e them because we don't have the
2180 function_result_decl to test. */
2181 if (!targetm.calls.allocate_stack_slots_for_args ())
2182 return true;
2183 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2184 if (optimize)
2185 return true;
2186 /* We don't set DECL_REGISTER for the function_result_decl. */
2187 return false;
2190 /* Decl is implicitly addressible by bound stores and loads
2191 if it is an aggregate holding bounds. */
2192 if (chkp_function_instrumented_p (current_function_decl)
2193 && TREE_TYPE (decl)
2194 && !BOUNDED_P (decl)
2195 && chkp_type_has_pointer (TREE_TYPE (decl)))
2196 return false;
2198 /* Only register-like things go in registers. */
2199 if (DECL_MODE (decl) == BLKmode)
2200 return false;
2202 /* If -ffloat-store specified, don't put explicit float variables
2203 into registers. */
2204 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2205 propagates values across these stores, and it probably shouldn't. */
2206 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2207 return false;
2209 if (!targetm.calls.allocate_stack_slots_for_args ())
2210 return true;
2212 /* If we're not interested in tracking debugging information for
2213 this decl, then we can certainly put it in a register. */
2214 if (DECL_IGNORED_P (decl))
2215 return true;
2217 if (optimize)
2218 return true;
2220 if (!DECL_REGISTER (decl))
2221 return false;
2223 /* When not optimizing, disregard register keyword for types that
2224 could have methods, otherwise the methods won't be callable from
2225 the debugger. */
2226 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl)))
2227 return false;
2229 return true;
2232 /* Structures to communicate between the subroutines of assign_parms.
2233 The first holds data persistent across all parameters, the second
2234 is cleared out for each parameter. */
2236 struct assign_parm_data_all
2238 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2239 should become a job of the target or otherwise encapsulated. */
2240 CUMULATIVE_ARGS args_so_far_v;
2241 cumulative_args_t args_so_far;
2242 struct args_size stack_args_size;
2243 tree function_result_decl;
2244 tree orig_fnargs;
2245 rtx_insn *first_conversion_insn;
2246 rtx_insn *last_conversion_insn;
2247 HOST_WIDE_INT pretend_args_size;
2248 HOST_WIDE_INT extra_pretend_bytes;
2249 int reg_parm_stack_space;
2252 struct assign_parm_data_one
2254 tree nominal_type;
2255 tree passed_type;
2256 rtx entry_parm;
2257 rtx stack_parm;
2258 machine_mode nominal_mode;
2259 machine_mode passed_mode;
2260 machine_mode promoted_mode;
2261 struct locate_and_pad_arg_data locate;
2262 int partial;
2263 BOOL_BITFIELD named_arg : 1;
2264 BOOL_BITFIELD passed_pointer : 1;
2265 BOOL_BITFIELD on_stack : 1;
2266 BOOL_BITFIELD loaded_in_reg : 1;
2269 struct bounds_parm_data
2271 assign_parm_data_one parm_data;
2272 tree bounds_parm;
2273 tree ptr_parm;
2274 rtx ptr_entry;
2275 int bound_no;
2278 /* A subroutine of assign_parms. Initialize ALL. */
2280 static void
2281 assign_parms_initialize_all (struct assign_parm_data_all *all)
2283 tree fntype ATTRIBUTE_UNUSED;
2285 memset (all, 0, sizeof (*all));
2287 fntype = TREE_TYPE (current_function_decl);
2289 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2290 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2291 #else
2292 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2293 current_function_decl, -1);
2294 #endif
2295 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2297 #ifdef INCOMING_REG_PARM_STACK_SPACE
2298 all->reg_parm_stack_space
2299 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2300 #endif
2303 /* If ARGS contains entries with complex types, split the entry into two
2304 entries of the component type. Return a new list of substitutions are
2305 needed, else the old list. */
2307 static void
2308 split_complex_args (vec<tree> *args)
2310 unsigned i;
2311 tree p;
2313 FOR_EACH_VEC_ELT (*args, i, p)
2315 tree type = TREE_TYPE (p);
2316 if (TREE_CODE (type) == COMPLEX_TYPE
2317 && targetm.calls.split_complex_arg (type))
2319 tree decl;
2320 tree subtype = TREE_TYPE (type);
2321 bool addressable = TREE_ADDRESSABLE (p);
2323 /* Rewrite the PARM_DECL's type with its component. */
2324 p = copy_node (p);
2325 TREE_TYPE (p) = subtype;
2326 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2327 SET_DECL_MODE (p, VOIDmode);
2328 DECL_SIZE (p) = NULL;
2329 DECL_SIZE_UNIT (p) = NULL;
2330 /* If this arg must go in memory, put it in a pseudo here.
2331 We can't allow it to go in memory as per normal parms,
2332 because the usual place might not have the imag part
2333 adjacent to the real part. */
2334 DECL_ARTIFICIAL (p) = addressable;
2335 DECL_IGNORED_P (p) = addressable;
2336 TREE_ADDRESSABLE (p) = 0;
2337 layout_decl (p, 0);
2338 (*args)[i] = p;
2340 /* Build a second synthetic decl. */
2341 decl = build_decl (EXPR_LOCATION (p),
2342 PARM_DECL, NULL_TREE, subtype);
2343 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2344 DECL_ARTIFICIAL (decl) = addressable;
2345 DECL_IGNORED_P (decl) = addressable;
2346 layout_decl (decl, 0);
2347 args->safe_insert (++i, decl);
2352 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2353 the hidden struct return argument, and (abi willing) complex args.
2354 Return the new parameter list. */
2356 static vec<tree>
2357 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2359 tree fndecl = current_function_decl;
2360 tree fntype = TREE_TYPE (fndecl);
2361 vec<tree> fnargs = vNULL;
2362 tree arg;
2364 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2365 fnargs.safe_push (arg);
2367 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2369 /* If struct value address is treated as the first argument, make it so. */
2370 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2371 && ! cfun->returns_pcc_struct
2372 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2374 tree type = build_pointer_type (TREE_TYPE (fntype));
2375 tree decl;
2377 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2378 PARM_DECL, get_identifier (".result_ptr"), type);
2379 DECL_ARG_TYPE (decl) = type;
2380 DECL_ARTIFICIAL (decl) = 1;
2381 DECL_NAMELESS (decl) = 1;
2382 TREE_CONSTANT (decl) = 1;
2383 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2384 changes, the end of the RESULT_DECL handling block in
2385 use_register_for_decl must be adjusted to match. */
2387 DECL_CHAIN (decl) = all->orig_fnargs;
2388 all->orig_fnargs = decl;
2389 fnargs.safe_insert (0, decl);
2391 all->function_result_decl = decl;
2393 /* If function is instrumented then bounds of the
2394 passed structure address is the second argument. */
2395 if (chkp_function_instrumented_p (fndecl))
2397 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2398 PARM_DECL, get_identifier (".result_bnd"),
2399 pointer_bounds_type_node);
2400 DECL_ARG_TYPE (decl) = pointer_bounds_type_node;
2401 DECL_ARTIFICIAL (decl) = 1;
2402 DECL_NAMELESS (decl) = 1;
2403 TREE_CONSTANT (decl) = 1;
2405 DECL_CHAIN (decl) = DECL_CHAIN (all->orig_fnargs);
2406 DECL_CHAIN (all->orig_fnargs) = decl;
2407 fnargs.safe_insert (1, decl);
2411 /* If the target wants to split complex arguments into scalars, do so. */
2412 if (targetm.calls.split_complex_arg)
2413 split_complex_args (&fnargs);
2415 return fnargs;
2418 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2419 data for the parameter. Incorporate ABI specifics such as pass-by-
2420 reference and type promotion. */
2422 static void
2423 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2424 struct assign_parm_data_one *data)
2426 tree nominal_type, passed_type;
2427 machine_mode nominal_mode, passed_mode, promoted_mode;
2428 int unsignedp;
2430 memset (data, 0, sizeof (*data));
2432 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2433 if (!cfun->stdarg)
2434 data->named_arg = 1; /* No variadic parms. */
2435 else if (DECL_CHAIN (parm))
2436 data->named_arg = 1; /* Not the last non-variadic parm. */
2437 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2438 data->named_arg = 1; /* Only variadic ones are unnamed. */
2439 else
2440 data->named_arg = 0; /* Treat as variadic. */
2442 nominal_type = TREE_TYPE (parm);
2443 passed_type = DECL_ARG_TYPE (parm);
2445 /* Look out for errors propagating this far. Also, if the parameter's
2446 type is void then its value doesn't matter. */
2447 if (TREE_TYPE (parm) == error_mark_node
2448 /* This can happen after weird syntax errors
2449 or if an enum type is defined among the parms. */
2450 || TREE_CODE (parm) != PARM_DECL
2451 || passed_type == NULL
2452 || VOID_TYPE_P (nominal_type))
2454 nominal_type = passed_type = void_type_node;
2455 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2456 goto egress;
2459 /* Find mode of arg as it is passed, and mode of arg as it should be
2460 during execution of this function. */
2461 passed_mode = TYPE_MODE (passed_type);
2462 nominal_mode = TYPE_MODE (nominal_type);
2464 /* If the parm is to be passed as a transparent union or record, use the
2465 type of the first field for the tests below. We have already verified
2466 that the modes are the same. */
2467 if ((TREE_CODE (passed_type) == UNION_TYPE
2468 || TREE_CODE (passed_type) == RECORD_TYPE)
2469 && TYPE_TRANSPARENT_AGGR (passed_type))
2470 passed_type = TREE_TYPE (first_field (passed_type));
2472 /* See if this arg was passed by invisible reference. */
2473 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2474 passed_type, data->named_arg))
2476 passed_type = nominal_type = build_pointer_type (passed_type);
2477 data->passed_pointer = true;
2478 passed_mode = nominal_mode = TYPE_MODE (nominal_type);
2481 /* Find mode as it is passed by the ABI. */
2482 unsignedp = TYPE_UNSIGNED (passed_type);
2483 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2484 TREE_TYPE (current_function_decl), 0);
2486 egress:
2487 data->nominal_type = nominal_type;
2488 data->passed_type = passed_type;
2489 data->nominal_mode = nominal_mode;
2490 data->passed_mode = passed_mode;
2491 data->promoted_mode = promoted_mode;
2494 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2496 static void
2497 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2498 struct assign_parm_data_one *data, bool no_rtl)
2500 int varargs_pretend_bytes = 0;
2502 targetm.calls.setup_incoming_varargs (all->args_so_far,
2503 data->promoted_mode,
2504 data->passed_type,
2505 &varargs_pretend_bytes, no_rtl);
2507 /* If the back-end has requested extra stack space, record how much is
2508 needed. Do not change pretend_args_size otherwise since it may be
2509 nonzero from an earlier partial argument. */
2510 if (varargs_pretend_bytes > 0)
2511 all->pretend_args_size = varargs_pretend_bytes;
2514 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2515 the incoming location of the current parameter. */
2517 static void
2518 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2519 struct assign_parm_data_one *data)
2521 HOST_WIDE_INT pretend_bytes = 0;
2522 rtx entry_parm;
2523 bool in_regs;
2525 if (data->promoted_mode == VOIDmode)
2527 data->entry_parm = data->stack_parm = const0_rtx;
2528 return;
2531 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2532 data->promoted_mode,
2533 data->passed_type,
2534 data->named_arg);
2536 if (entry_parm == 0)
2537 data->promoted_mode = data->passed_mode;
2539 /* Determine parm's home in the stack, in case it arrives in the stack
2540 or we should pretend it did. Compute the stack position and rtx where
2541 the argument arrives and its size.
2543 There is one complexity here: If this was a parameter that would
2544 have been passed in registers, but wasn't only because it is
2545 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2546 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2547 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2548 as it was the previous time. */
2549 in_regs = (entry_parm != 0) || POINTER_BOUNDS_TYPE_P (data->passed_type);
2550 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2551 in_regs = true;
2552 #endif
2553 if (!in_regs && !data->named_arg)
2555 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2557 rtx tem;
2558 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2559 data->promoted_mode,
2560 data->passed_type, true);
2561 in_regs = tem != NULL;
2565 /* If this parameter was passed both in registers and in the stack, use
2566 the copy on the stack. */
2567 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2568 data->passed_type))
2569 entry_parm = 0;
2571 if (entry_parm)
2573 int partial;
2575 partial = targetm.calls.arg_partial_bytes (all->args_so_far,
2576 data->promoted_mode,
2577 data->passed_type,
2578 data->named_arg);
2579 data->partial = partial;
2581 /* The caller might already have allocated stack space for the
2582 register parameters. */
2583 if (partial != 0 && all->reg_parm_stack_space == 0)
2585 /* Part of this argument is passed in registers and part
2586 is passed on the stack. Ask the prologue code to extend
2587 the stack part so that we can recreate the full value.
2589 PRETEND_BYTES is the size of the registers we need to store.
2590 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2591 stack space that the prologue should allocate.
2593 Internally, gcc assumes that the argument pointer is aligned
2594 to STACK_BOUNDARY bits. This is used both for alignment
2595 optimizations (see init_emit) and to locate arguments that are
2596 aligned to more than PARM_BOUNDARY bits. We must preserve this
2597 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2598 a stack boundary. */
2600 /* We assume at most one partial arg, and it must be the first
2601 argument on the stack. */
2602 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2604 pretend_bytes = partial;
2605 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2607 /* We want to align relative to the actual stack pointer, so
2608 don't include this in the stack size until later. */
2609 all->extra_pretend_bytes = all->pretend_args_size;
2613 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2614 all->reg_parm_stack_space,
2615 entry_parm ? data->partial : 0, current_function_decl,
2616 &all->stack_args_size, &data->locate);
2618 /* Update parm_stack_boundary if this parameter is passed in the
2619 stack. */
2620 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2621 crtl->parm_stack_boundary = data->locate.boundary;
2623 /* Adjust offsets to include the pretend args. */
2624 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2625 data->locate.slot_offset.constant += pretend_bytes;
2626 data->locate.offset.constant += pretend_bytes;
2628 data->entry_parm = entry_parm;
2631 /* A subroutine of assign_parms. If there is actually space on the stack
2632 for this parm, count it in stack_args_size and return true. */
2634 static bool
2635 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2636 struct assign_parm_data_one *data)
2638 /* Bounds are never passed on the stack to keep compatibility
2639 with not instrumented code. */
2640 if (POINTER_BOUNDS_TYPE_P (data->passed_type))
2641 return false;
2642 /* Trivially true if we've no incoming register. */
2643 else if (data->entry_parm == NULL)
2645 /* Also true if we're partially in registers and partially not,
2646 since we've arranged to drop the entire argument on the stack. */
2647 else if (data->partial != 0)
2649 /* Also true if the target says that it's passed in both registers
2650 and on the stack. */
2651 else if (GET_CODE (data->entry_parm) == PARALLEL
2652 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2654 /* Also true if the target says that there's stack allocated for
2655 all register parameters. */
2656 else if (all->reg_parm_stack_space > 0)
2658 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2659 else
2660 return false;
2662 all->stack_args_size.constant += data->locate.size.constant;
2663 if (data->locate.size.var)
2664 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2666 return true;
2669 /* A subroutine of assign_parms. Given that this parameter is allocated
2670 stack space by the ABI, find it. */
2672 static void
2673 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2675 rtx offset_rtx, stack_parm;
2676 unsigned int align, boundary;
2678 /* If we're passing this arg using a reg, make its stack home the
2679 aligned stack slot. */
2680 if (data->entry_parm)
2681 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2682 else
2683 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2685 stack_parm = crtl->args.internal_arg_pointer;
2686 if (offset_rtx != const0_rtx)
2687 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2688 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2690 if (!data->passed_pointer)
2692 set_mem_attributes (stack_parm, parm, 1);
2693 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2694 while promoted mode's size is needed. */
2695 if (data->promoted_mode != BLKmode
2696 && data->promoted_mode != DECL_MODE (parm))
2698 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2699 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2701 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2702 data->promoted_mode);
2703 if (offset)
2704 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2709 boundary = data->locate.boundary;
2710 align = BITS_PER_UNIT;
2712 /* If we're padding upward, we know that the alignment of the slot
2713 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2714 intentionally forcing upward padding. Otherwise we have to come
2715 up with a guess at the alignment based on OFFSET_RTX. */
2716 if (data->locate.where_pad != downward || data->entry_parm)
2717 align = boundary;
2718 else if (CONST_INT_P (offset_rtx))
2720 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2721 align = least_bit_hwi (align);
2723 set_mem_align (stack_parm, align);
2725 if (data->entry_parm)
2726 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2728 data->stack_parm = stack_parm;
2731 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2732 always valid and contiguous. */
2734 static void
2735 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2737 rtx entry_parm = data->entry_parm;
2738 rtx stack_parm = data->stack_parm;
2740 /* If this parm was passed part in regs and part in memory, pretend it
2741 arrived entirely in memory by pushing the register-part onto the stack.
2742 In the special case of a DImode or DFmode that is split, we could put
2743 it together in a pseudoreg directly, but for now that's not worth
2744 bothering with. */
2745 if (data->partial != 0)
2747 /* Handle calls that pass values in multiple non-contiguous
2748 locations. The Irix 6 ABI has examples of this. */
2749 if (GET_CODE (entry_parm) == PARALLEL)
2750 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2751 data->passed_type,
2752 int_size_in_bytes (data->passed_type));
2753 else
2755 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2756 move_block_from_reg (REGNO (entry_parm),
2757 validize_mem (copy_rtx (stack_parm)),
2758 data->partial / UNITS_PER_WORD);
2761 entry_parm = stack_parm;
2764 /* If we didn't decide this parm came in a register, by default it came
2765 on the stack. */
2766 else if (entry_parm == NULL)
2767 entry_parm = stack_parm;
2769 /* When an argument is passed in multiple locations, we can't make use
2770 of this information, but we can save some copying if the whole argument
2771 is passed in a single register. */
2772 else if (GET_CODE (entry_parm) == PARALLEL
2773 && data->nominal_mode != BLKmode
2774 && data->passed_mode != BLKmode)
2776 size_t i, len = XVECLEN (entry_parm, 0);
2778 for (i = 0; i < len; i++)
2779 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2780 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2781 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2782 == data->passed_mode)
2783 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2785 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2786 break;
2790 data->entry_parm = entry_parm;
2793 /* A subroutine of assign_parms. Reconstitute any values which were
2794 passed in multiple registers and would fit in a single register. */
2796 static void
2797 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2799 rtx entry_parm = data->entry_parm;
2801 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2802 This can be done with register operations rather than on the
2803 stack, even if we will store the reconstituted parameter on the
2804 stack later. */
2805 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2807 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2808 emit_group_store (parmreg, entry_parm, data->passed_type,
2809 GET_MODE_SIZE (GET_MODE (entry_parm)));
2810 entry_parm = parmreg;
2813 data->entry_parm = entry_parm;
2816 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2817 always valid and properly aligned. */
2819 static void
2820 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2822 rtx stack_parm = data->stack_parm;
2824 /* If we can't trust the parm stack slot to be aligned enough for its
2825 ultimate type, don't use that slot after entry. We'll make another
2826 stack slot, if we need one. */
2827 if (stack_parm
2828 && ((STRICT_ALIGNMENT
2829 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2830 || (data->nominal_type
2831 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2832 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2833 stack_parm = NULL;
2835 /* If parm was passed in memory, and we need to convert it on entry,
2836 don't store it back in that same slot. */
2837 else if (data->entry_parm == stack_parm
2838 && data->nominal_mode != BLKmode
2839 && data->nominal_mode != data->passed_mode)
2840 stack_parm = NULL;
2842 /* If stack protection is in effect for this function, don't leave any
2843 pointers in their passed stack slots. */
2844 else if (crtl->stack_protect_guard
2845 && (flag_stack_protect == 2
2846 || data->passed_pointer
2847 || POINTER_TYPE_P (data->nominal_type)))
2848 stack_parm = NULL;
2850 data->stack_parm = stack_parm;
2853 /* A subroutine of assign_parms. Return true if the current parameter
2854 should be stored as a BLKmode in the current frame. */
2856 static bool
2857 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2859 if (data->nominal_mode == BLKmode)
2860 return true;
2861 if (GET_MODE (data->entry_parm) == BLKmode)
2862 return true;
2864 #ifdef BLOCK_REG_PADDING
2865 /* Only assign_parm_setup_block knows how to deal with register arguments
2866 that are padded at the least significant end. */
2867 if (REG_P (data->entry_parm)
2868 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2869 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2870 == (BYTES_BIG_ENDIAN ? upward : downward)))
2871 return true;
2872 #endif
2874 return false;
2877 /* A subroutine of assign_parms. Arrange for the parameter to be
2878 present and valid in DATA->STACK_RTL. */
2880 static void
2881 assign_parm_setup_block (struct assign_parm_data_all *all,
2882 tree parm, struct assign_parm_data_one *data)
2884 rtx entry_parm = data->entry_parm;
2885 rtx stack_parm = data->stack_parm;
2886 rtx target_reg = NULL_RTX;
2887 bool in_conversion_seq = false;
2888 HOST_WIDE_INT size;
2889 HOST_WIDE_INT size_stored;
2891 if (GET_CODE (entry_parm) == PARALLEL)
2892 entry_parm = emit_group_move_into_temps (entry_parm);
2894 /* If we want the parameter in a pseudo, don't use a stack slot. */
2895 if (is_gimple_reg (parm) && use_register_for_decl (parm))
2897 tree def = ssa_default_def (cfun, parm);
2898 gcc_assert (def);
2899 machine_mode mode = promote_ssa_mode (def, NULL);
2900 rtx reg = gen_reg_rtx (mode);
2901 if (GET_CODE (reg) != CONCAT)
2902 stack_parm = reg;
2903 else
2905 target_reg = reg;
2906 /* Avoid allocating a stack slot, if there isn't one
2907 preallocated by the ABI. It might seem like we should
2908 always prefer a pseudo, but converting between
2909 floating-point and integer modes goes through the stack
2910 on various machines, so it's better to use the reserved
2911 stack slot than to risk wasting it and allocating more
2912 for the conversion. */
2913 if (stack_parm == NULL_RTX)
2915 int save = generating_concat_p;
2916 generating_concat_p = 0;
2917 stack_parm = gen_reg_rtx (mode);
2918 generating_concat_p = save;
2921 data->stack_parm = NULL;
2924 size = int_size_in_bytes (data->passed_type);
2925 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2926 if (stack_parm == 0)
2928 SET_DECL_ALIGN (parm, MAX (DECL_ALIGN (parm), BITS_PER_WORD));
2929 stack_parm = assign_stack_local (BLKmode, size_stored,
2930 DECL_ALIGN (parm));
2931 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2932 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2933 set_mem_attributes (stack_parm, parm, 1);
2936 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2937 calls that pass values in multiple non-contiguous locations. */
2938 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2940 rtx mem;
2942 /* Note that we will be storing an integral number of words.
2943 So we have to be careful to ensure that we allocate an
2944 integral number of words. We do this above when we call
2945 assign_stack_local if space was not allocated in the argument
2946 list. If it was, this will not work if PARM_BOUNDARY is not
2947 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2948 if it becomes a problem. Exception is when BLKmode arrives
2949 with arguments not conforming to word_mode. */
2951 if (data->stack_parm == 0)
2953 else if (GET_CODE (entry_parm) == PARALLEL)
2955 else
2956 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2958 mem = validize_mem (copy_rtx (stack_parm));
2960 /* Handle values in multiple non-contiguous locations. */
2961 if (GET_CODE (entry_parm) == PARALLEL && !MEM_P (mem))
2962 emit_group_store (mem, entry_parm, data->passed_type, size);
2963 else if (GET_CODE (entry_parm) == PARALLEL)
2965 push_to_sequence2 (all->first_conversion_insn,
2966 all->last_conversion_insn);
2967 emit_group_store (mem, entry_parm, data->passed_type, size);
2968 all->first_conversion_insn = get_insns ();
2969 all->last_conversion_insn = get_last_insn ();
2970 end_sequence ();
2971 in_conversion_seq = true;
2974 else if (size == 0)
2977 /* If SIZE is that of a mode no bigger than a word, just use
2978 that mode's store operation. */
2979 else if (size <= UNITS_PER_WORD)
2981 machine_mode mode
2982 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2984 if (mode != BLKmode
2985 #ifdef BLOCK_REG_PADDING
2986 && (size == UNITS_PER_WORD
2987 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2988 != (BYTES_BIG_ENDIAN ? upward : downward)))
2989 #endif
2992 rtx reg;
2994 /* We are really truncating a word_mode value containing
2995 SIZE bytes into a value of mode MODE. If such an
2996 operation requires no actual instructions, we can refer
2997 to the value directly in mode MODE, otherwise we must
2998 start with the register in word_mode and explicitly
2999 convert it. */
3000 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
3001 reg = gen_rtx_REG (mode, REGNO (entry_parm));
3002 else
3004 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3005 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
3007 emit_move_insn (change_address (mem, mode, 0), reg);
3010 #ifdef BLOCK_REG_PADDING
3011 /* Storing the register in memory as a full word, as
3012 move_block_from_reg below would do, and then using the
3013 MEM in a smaller mode, has the effect of shifting right
3014 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3015 shifting must be explicit. */
3016 else if (!MEM_P (mem))
3018 rtx x;
3020 /* If the assert below fails, we should have taken the
3021 mode != BLKmode path above, unless we have downward
3022 padding of smaller-than-word arguments on a machine
3023 with little-endian bytes, which would likely require
3024 additional changes to work correctly. */
3025 gcc_checking_assert (BYTES_BIG_ENDIAN
3026 && (BLOCK_REG_PADDING (mode,
3027 data->passed_type, 1)
3028 == upward));
3030 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3032 x = gen_rtx_REG (word_mode, REGNO (entry_parm));
3033 x = expand_shift (RSHIFT_EXPR, word_mode, x, by,
3034 NULL_RTX, 1);
3035 x = force_reg (word_mode, x);
3036 x = gen_lowpart_SUBREG (GET_MODE (mem), x);
3038 emit_move_insn (mem, x);
3040 #endif
3042 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3043 machine must be aligned to the left before storing
3044 to memory. Note that the previous test doesn't
3045 handle all cases (e.g. SIZE == 3). */
3046 else if (size != UNITS_PER_WORD
3047 #ifdef BLOCK_REG_PADDING
3048 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
3049 == downward)
3050 #else
3051 && BYTES_BIG_ENDIAN
3052 #endif
3055 rtx tem, x;
3056 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
3057 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
3059 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
3060 tem = change_address (mem, word_mode, 0);
3061 emit_move_insn (tem, x);
3063 else
3064 move_block_from_reg (REGNO (entry_parm), mem,
3065 size_stored / UNITS_PER_WORD);
3067 else if (!MEM_P (mem))
3069 gcc_checking_assert (size > UNITS_PER_WORD);
3070 #ifdef BLOCK_REG_PADDING
3071 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem),
3072 data->passed_type, 0)
3073 == upward);
3074 #endif
3075 emit_move_insn (mem, entry_parm);
3077 else
3078 move_block_from_reg (REGNO (entry_parm), mem,
3079 size_stored / UNITS_PER_WORD);
3081 else if (data->stack_parm == 0)
3083 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3084 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
3085 BLOCK_OP_NORMAL);
3086 all->first_conversion_insn = get_insns ();
3087 all->last_conversion_insn = get_last_insn ();
3088 end_sequence ();
3089 in_conversion_seq = true;
3092 if (target_reg)
3094 if (!in_conversion_seq)
3095 emit_move_insn (target_reg, stack_parm);
3096 else
3098 push_to_sequence2 (all->first_conversion_insn,
3099 all->last_conversion_insn);
3100 emit_move_insn (target_reg, stack_parm);
3101 all->first_conversion_insn = get_insns ();
3102 all->last_conversion_insn = get_last_insn ();
3103 end_sequence ();
3105 stack_parm = target_reg;
3108 data->stack_parm = stack_parm;
3109 set_parm_rtl (parm, stack_parm);
3112 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3113 parameter. Get it there. Perform all ABI specified conversions. */
3115 static void
3116 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
3117 struct assign_parm_data_one *data)
3119 rtx parmreg, validated_mem;
3120 rtx equiv_stack_parm;
3121 machine_mode promoted_nominal_mode;
3122 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
3123 bool did_conversion = false;
3124 bool need_conversion, moved;
3125 rtx rtl;
3127 /* Store the parm in a pseudoregister during the function, but we may
3128 need to do it in a wider mode. Using 2 here makes the result
3129 consistent with promote_decl_mode and thus expand_expr_real_1. */
3130 promoted_nominal_mode
3131 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
3132 TREE_TYPE (current_function_decl), 2);
3134 parmreg = gen_reg_rtx (promoted_nominal_mode);
3135 if (!DECL_ARTIFICIAL (parm))
3136 mark_user_reg (parmreg);
3138 /* If this was an item that we received a pointer to,
3139 set rtl appropriately. */
3140 if (data->passed_pointer)
3142 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
3143 set_mem_attributes (rtl, parm, 1);
3145 else
3146 rtl = parmreg;
3148 assign_parm_remove_parallels (data);
3150 /* Copy the value into the register, thus bridging between
3151 assign_parm_find_data_types and expand_expr_real_1. */
3153 equiv_stack_parm = data->stack_parm;
3154 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3156 need_conversion = (data->nominal_mode != data->passed_mode
3157 || promoted_nominal_mode != data->promoted_mode);
3158 moved = false;
3160 if (need_conversion
3161 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3162 && data->nominal_mode == data->passed_mode
3163 && data->nominal_mode == GET_MODE (data->entry_parm))
3165 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3166 mode, by the caller. We now have to convert it to
3167 NOMINAL_MODE, if different. However, PARMREG may be in
3168 a different mode than NOMINAL_MODE if it is being stored
3169 promoted.
3171 If ENTRY_PARM is a hard register, it might be in a register
3172 not valid for operating in its mode (e.g., an odd-numbered
3173 register for a DFmode). In that case, moves are the only
3174 thing valid, so we can't do a convert from there. This
3175 occurs when the calling sequence allow such misaligned
3176 usages.
3178 In addition, the conversion may involve a call, which could
3179 clobber parameters which haven't been copied to pseudo
3180 registers yet.
3182 First, we try to emit an insn which performs the necessary
3183 conversion. We verify that this insn does not clobber any
3184 hard registers. */
3186 enum insn_code icode;
3187 rtx op0, op1;
3189 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3190 unsignedp);
3192 op0 = parmreg;
3193 op1 = validated_mem;
3194 if (icode != CODE_FOR_nothing
3195 && insn_operand_matches (icode, 0, op0)
3196 && insn_operand_matches (icode, 1, op1))
3198 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3199 rtx_insn *insn, *insns;
3200 rtx t = op1;
3201 HARD_REG_SET hardregs;
3203 start_sequence ();
3204 /* If op1 is a hard register that is likely spilled, first
3205 force it into a pseudo, otherwise combiner might extend
3206 its lifetime too much. */
3207 if (GET_CODE (t) == SUBREG)
3208 t = SUBREG_REG (t);
3209 if (REG_P (t)
3210 && HARD_REGISTER_P (t)
3211 && ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
3212 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
3214 t = gen_reg_rtx (GET_MODE (op1));
3215 emit_move_insn (t, op1);
3217 else
3218 t = op1;
3219 rtx_insn *pat = gen_extend_insn (op0, t, promoted_nominal_mode,
3220 data->passed_mode, unsignedp);
3221 emit_insn (pat);
3222 insns = get_insns ();
3224 moved = true;
3225 CLEAR_HARD_REG_SET (hardregs);
3226 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3228 if (INSN_P (insn))
3229 note_stores (PATTERN (insn), record_hard_reg_sets,
3230 &hardregs);
3231 if (!hard_reg_set_empty_p (hardregs))
3232 moved = false;
3235 end_sequence ();
3237 if (moved)
3239 emit_insn (insns);
3240 if (equiv_stack_parm != NULL_RTX)
3241 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3242 equiv_stack_parm);
3247 if (moved)
3248 /* Nothing to do. */
3250 else if (need_conversion)
3252 /* We did not have an insn to convert directly, or the sequence
3253 generated appeared unsafe. We must first copy the parm to a
3254 pseudo reg, and save the conversion until after all
3255 parameters have been moved. */
3257 int save_tree_used;
3258 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3260 emit_move_insn (tempreg, validated_mem);
3262 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3263 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3265 if (GET_CODE (tempreg) == SUBREG
3266 && GET_MODE (tempreg) == data->nominal_mode
3267 && REG_P (SUBREG_REG (tempreg))
3268 && data->nominal_mode == data->passed_mode
3269 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
3270 && GET_MODE_SIZE (GET_MODE (tempreg))
3271 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
3273 /* The argument is already sign/zero extended, so note it
3274 into the subreg. */
3275 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3276 SUBREG_PROMOTED_SET (tempreg, unsignedp);
3279 /* TREE_USED gets set erroneously during expand_assignment. */
3280 save_tree_used = TREE_USED (parm);
3281 SET_DECL_RTL (parm, rtl);
3282 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3283 SET_DECL_RTL (parm, NULL_RTX);
3284 TREE_USED (parm) = save_tree_used;
3285 all->first_conversion_insn = get_insns ();
3286 all->last_conversion_insn = get_last_insn ();
3287 end_sequence ();
3289 did_conversion = true;
3291 else
3292 emit_move_insn (parmreg, validated_mem);
3294 /* If we were passed a pointer but the actual value can safely live
3295 in a register, retrieve it and use it directly. */
3296 if (data->passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3298 /* We can't use nominal_mode, because it will have been set to
3299 Pmode above. We must use the actual mode of the parm. */
3300 if (use_register_for_decl (parm))
3302 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3303 mark_user_reg (parmreg);
3305 else
3307 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3308 TYPE_MODE (TREE_TYPE (parm)),
3309 TYPE_ALIGN (TREE_TYPE (parm)));
3310 parmreg
3311 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3312 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3313 align);
3314 set_mem_attributes (parmreg, parm, 1);
3317 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3318 the debug info in case it is not legitimate. */
3319 if (GET_MODE (parmreg) != GET_MODE (rtl))
3321 rtx tempreg = gen_reg_rtx (GET_MODE (rtl));
3322 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3324 push_to_sequence2 (all->first_conversion_insn,
3325 all->last_conversion_insn);
3326 emit_move_insn (tempreg, rtl);
3327 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3328 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg,
3329 tempreg);
3330 all->first_conversion_insn = get_insns ();
3331 all->last_conversion_insn = get_last_insn ();
3332 end_sequence ();
3334 did_conversion = true;
3336 else
3337 emit_move_insn (MEM_P (parmreg) ? copy_rtx (parmreg) : parmreg, rtl);
3339 rtl = parmreg;
3341 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3342 now the parm. */
3343 data->stack_parm = NULL;
3346 set_parm_rtl (parm, rtl);
3348 /* Mark the register as eliminable if we did no conversion and it was
3349 copied from memory at a fixed offset, and the arg pointer was not
3350 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3351 offset formed an invalid address, such memory-equivalences as we
3352 make here would screw up life analysis for it. */
3353 if (data->nominal_mode == data->passed_mode
3354 && !did_conversion
3355 && data->stack_parm != 0
3356 && MEM_P (data->stack_parm)
3357 && data->locate.offset.var == 0
3358 && reg_mentioned_p (virtual_incoming_args_rtx,
3359 XEXP (data->stack_parm, 0)))
3361 rtx_insn *linsn = get_last_insn ();
3362 rtx_insn *sinsn;
3363 rtx set;
3365 /* Mark complex types separately. */
3366 if (GET_CODE (parmreg) == CONCAT)
3368 scalar_mode submode = GET_MODE_INNER (GET_MODE (parmreg));
3369 int regnor = REGNO (XEXP (parmreg, 0));
3370 int regnoi = REGNO (XEXP (parmreg, 1));
3371 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3372 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3373 GET_MODE_SIZE (submode));
3375 /* Scan backwards for the set of the real and
3376 imaginary parts. */
3377 for (sinsn = linsn; sinsn != 0;
3378 sinsn = prev_nonnote_insn (sinsn))
3380 set = single_set (sinsn);
3381 if (set == 0)
3382 continue;
3384 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3385 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3386 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3387 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3390 else
3391 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3394 /* For pointer data type, suggest pointer register. */
3395 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3396 mark_reg_pointer (parmreg,
3397 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3400 /* A subroutine of assign_parms. Allocate stack space to hold the current
3401 parameter. Get it there. Perform all ABI specified conversions. */
3403 static void
3404 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3405 struct assign_parm_data_one *data)
3407 /* Value must be stored in the stack slot STACK_PARM during function
3408 execution. */
3409 bool to_conversion = false;
3411 assign_parm_remove_parallels (data);
3413 if (data->promoted_mode != data->nominal_mode)
3415 /* Conversion is required. */
3416 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3418 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3420 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3421 to_conversion = true;
3423 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3424 TYPE_UNSIGNED (TREE_TYPE (parm)));
3426 if (data->stack_parm)
3428 int offset = subreg_lowpart_offset (data->nominal_mode,
3429 GET_MODE (data->stack_parm));
3430 /* ??? This may need a big-endian conversion on sparc64. */
3431 data->stack_parm
3432 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3433 if (offset && MEM_OFFSET_KNOWN_P (data->stack_parm))
3434 set_mem_offset (data->stack_parm,
3435 MEM_OFFSET (data->stack_parm) + offset);
3439 if (data->entry_parm != data->stack_parm)
3441 rtx src, dest;
3443 if (data->stack_parm == 0)
3445 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3446 GET_MODE (data->entry_parm),
3447 TYPE_ALIGN (data->passed_type));
3448 data->stack_parm
3449 = assign_stack_local (GET_MODE (data->entry_parm),
3450 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3451 align);
3452 set_mem_attributes (data->stack_parm, parm, 1);
3455 dest = validize_mem (copy_rtx (data->stack_parm));
3456 src = validize_mem (copy_rtx (data->entry_parm));
3458 if (MEM_P (src))
3460 /* Use a block move to handle potentially misaligned entry_parm. */
3461 if (!to_conversion)
3462 push_to_sequence2 (all->first_conversion_insn,
3463 all->last_conversion_insn);
3464 to_conversion = true;
3466 emit_block_move (dest, src,
3467 GEN_INT (int_size_in_bytes (data->passed_type)),
3468 BLOCK_OP_NORMAL);
3470 else
3472 if (!REG_P (src))
3473 src = force_reg (GET_MODE (src), src);
3474 emit_move_insn (dest, src);
3478 if (to_conversion)
3480 all->first_conversion_insn = get_insns ();
3481 all->last_conversion_insn = get_last_insn ();
3482 end_sequence ();
3485 set_parm_rtl (parm, data->stack_parm);
3488 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3489 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3491 static void
3492 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3493 vec<tree> fnargs)
3495 tree parm;
3496 tree orig_fnargs = all->orig_fnargs;
3497 unsigned i = 0;
3499 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3501 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3502 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3504 rtx tmp, real, imag;
3505 scalar_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3507 real = DECL_RTL (fnargs[i]);
3508 imag = DECL_RTL (fnargs[i + 1]);
3509 if (inner != GET_MODE (real))
3511 real = gen_lowpart_SUBREG (inner, real);
3512 imag = gen_lowpart_SUBREG (inner, imag);
3515 if (TREE_ADDRESSABLE (parm))
3517 rtx rmem, imem;
3518 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3519 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3520 DECL_MODE (parm),
3521 TYPE_ALIGN (TREE_TYPE (parm)));
3523 /* split_complex_arg put the real and imag parts in
3524 pseudos. Move them to memory. */
3525 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3526 set_mem_attributes (tmp, parm, 1);
3527 rmem = adjust_address_nv (tmp, inner, 0);
3528 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3529 push_to_sequence2 (all->first_conversion_insn,
3530 all->last_conversion_insn);
3531 emit_move_insn (rmem, real);
3532 emit_move_insn (imem, imag);
3533 all->first_conversion_insn = get_insns ();
3534 all->last_conversion_insn = get_last_insn ();
3535 end_sequence ();
3537 else
3538 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3539 set_parm_rtl (parm, tmp);
3541 real = DECL_INCOMING_RTL (fnargs[i]);
3542 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3543 if (inner != GET_MODE (real))
3545 real = gen_lowpart_SUBREG (inner, real);
3546 imag = gen_lowpart_SUBREG (inner, imag);
3548 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3549 set_decl_incoming_rtl (parm, tmp, false);
3550 i++;
3555 /* Load bounds of PARM from bounds table. */
3556 static void
3557 assign_parm_load_bounds (struct assign_parm_data_one *data,
3558 tree parm,
3559 rtx entry,
3560 unsigned bound_no)
3562 bitmap_iterator bi;
3563 unsigned i, offs = 0;
3564 int bnd_no = -1;
3565 rtx slot = NULL, ptr = NULL;
3567 if (parm)
3569 bitmap slots;
3570 bitmap_obstack_initialize (NULL);
3571 slots = BITMAP_ALLOC (NULL);
3572 chkp_find_bound_slots (TREE_TYPE (parm), slots);
3573 EXECUTE_IF_SET_IN_BITMAP (slots, 0, i, bi)
3575 if (bound_no)
3576 bound_no--;
3577 else
3579 bnd_no = i;
3580 break;
3583 BITMAP_FREE (slots);
3584 bitmap_obstack_release (NULL);
3587 /* We may have bounds not associated with any pointer. */
3588 if (bnd_no != -1)
3589 offs = bnd_no * POINTER_SIZE / BITS_PER_UNIT;
3591 /* Find associated pointer. */
3592 if (bnd_no == -1)
3594 /* If bounds are not associated with any bounds,
3595 then it is passed in a register or special slot. */
3596 gcc_assert (data->entry_parm);
3597 ptr = const0_rtx;
3599 else if (MEM_P (entry))
3600 slot = adjust_address (entry, Pmode, offs);
3601 else if (REG_P (entry))
3602 ptr = gen_rtx_REG (Pmode, REGNO (entry) + bnd_no);
3603 else if (GET_CODE (entry) == PARALLEL)
3604 ptr = chkp_get_value_with_offs (entry, GEN_INT (offs));
3605 else
3606 gcc_unreachable ();
3607 data->entry_parm = targetm.calls.load_bounds_for_arg (slot, ptr,
3608 data->entry_parm);
3611 /* Assign RTL expressions to the function's bounds parameters BNDARGS. */
3613 static void
3614 assign_bounds (vec<bounds_parm_data> &bndargs,
3615 struct assign_parm_data_all &all,
3616 bool assign_regs, bool assign_special,
3617 bool assign_bt)
3619 unsigned i, pass;
3620 bounds_parm_data *pbdata;
3622 if (!bndargs.exists ())
3623 return;
3625 /* We make few passes to store input bounds. Firstly handle bounds
3626 passed in registers. After that we load bounds passed in special
3627 slots. Finally we load bounds from Bounds Table. */
3628 for (pass = 0; pass < 3; pass++)
3629 FOR_EACH_VEC_ELT (bndargs, i, pbdata)
3631 /* Pass 0 => regs only. */
3632 if (pass == 0
3633 && (!assign_regs
3634 ||(!pbdata->parm_data.entry_parm
3635 || GET_CODE (pbdata->parm_data.entry_parm) != REG)))
3636 continue;
3637 /* Pass 1 => slots only. */
3638 else if (pass == 1
3639 && (!assign_special
3640 || (!pbdata->parm_data.entry_parm
3641 || GET_CODE (pbdata->parm_data.entry_parm) == REG)))
3642 continue;
3643 /* Pass 2 => BT only. */
3644 else if (pass == 2
3645 && (!assign_bt
3646 || pbdata->parm_data.entry_parm))
3647 continue;
3649 if (!pbdata->parm_data.entry_parm
3650 || GET_CODE (pbdata->parm_data.entry_parm) != REG)
3651 assign_parm_load_bounds (&pbdata->parm_data, pbdata->ptr_parm,
3652 pbdata->ptr_entry, pbdata->bound_no);
3654 set_decl_incoming_rtl (pbdata->bounds_parm,
3655 pbdata->parm_data.entry_parm, false);
3657 if (assign_parm_setup_block_p (&pbdata->parm_data))
3658 assign_parm_setup_block (&all, pbdata->bounds_parm,
3659 &pbdata->parm_data);
3660 else if (pbdata->parm_data.passed_pointer
3661 || use_register_for_decl (pbdata->bounds_parm))
3662 assign_parm_setup_reg (&all, pbdata->bounds_parm,
3663 &pbdata->parm_data);
3664 else
3665 assign_parm_setup_stack (&all, pbdata->bounds_parm,
3666 &pbdata->parm_data);
3670 /* Assign RTL expressions to the function's parameters. This may involve
3671 copying them into registers and using those registers as the DECL_RTL. */
3673 static void
3674 assign_parms (tree fndecl)
3676 struct assign_parm_data_all all;
3677 tree parm;
3678 vec<tree> fnargs;
3679 unsigned i, bound_no = 0;
3680 tree last_arg = NULL;
3681 rtx last_arg_entry = NULL;
3682 vec<bounds_parm_data> bndargs = vNULL;
3683 bounds_parm_data bdata;
3685 crtl->args.internal_arg_pointer
3686 = targetm.calls.internal_arg_pointer ();
3688 assign_parms_initialize_all (&all);
3689 fnargs = assign_parms_augmented_arg_list (&all);
3691 FOR_EACH_VEC_ELT (fnargs, i, parm)
3693 struct assign_parm_data_one data;
3695 /* Extract the type of PARM; adjust it according to ABI. */
3696 assign_parm_find_data_types (&all, parm, &data);
3698 /* Early out for errors and void parameters. */
3699 if (data.passed_mode == VOIDmode)
3701 SET_DECL_RTL (parm, const0_rtx);
3702 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3703 continue;
3706 /* Estimate stack alignment from parameter alignment. */
3707 if (SUPPORTS_STACK_ALIGNMENT)
3709 unsigned int align
3710 = targetm.calls.function_arg_boundary (data.promoted_mode,
3711 data.passed_type);
3712 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3713 align);
3714 if (TYPE_ALIGN (data.nominal_type) > align)
3715 align = MINIMUM_ALIGNMENT (data.nominal_type,
3716 TYPE_MODE (data.nominal_type),
3717 TYPE_ALIGN (data.nominal_type));
3718 if (crtl->stack_alignment_estimated < align)
3720 gcc_assert (!crtl->stack_realign_processed);
3721 crtl->stack_alignment_estimated = align;
3725 /* Find out where the parameter arrives in this function. */
3726 assign_parm_find_entry_rtl (&all, &data);
3728 /* Find out where stack space for this parameter might be. */
3729 if (assign_parm_is_stack_parm (&all, &data))
3731 assign_parm_find_stack_rtl (parm, &data);
3732 assign_parm_adjust_entry_rtl (&data);
3734 if (!POINTER_BOUNDS_TYPE_P (data.passed_type))
3736 /* Remember where last non bounds arg was passed in case
3737 we have to load associated bounds for it from Bounds
3738 Table. */
3739 last_arg = parm;
3740 last_arg_entry = data.entry_parm;
3741 bound_no = 0;
3743 /* Record permanently how this parm was passed. */
3744 if (data.passed_pointer)
3746 rtx incoming_rtl
3747 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3748 data.entry_parm);
3749 set_decl_incoming_rtl (parm, incoming_rtl, true);
3751 else
3752 set_decl_incoming_rtl (parm, data.entry_parm, false);
3754 assign_parm_adjust_stack_rtl (&data);
3756 /* Bounds should be loaded in the particular order to
3757 have registers allocated correctly. Collect info about
3758 input bounds and load them later. */
3759 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3761 /* Expect bounds in instrumented functions only. */
3762 gcc_assert (chkp_function_instrumented_p (fndecl));
3764 bdata.parm_data = data;
3765 bdata.bounds_parm = parm;
3766 bdata.ptr_parm = last_arg;
3767 bdata.ptr_entry = last_arg_entry;
3768 bdata.bound_no = bound_no;
3769 bndargs.safe_push (bdata);
3771 else
3773 if (assign_parm_setup_block_p (&data))
3774 assign_parm_setup_block (&all, parm, &data);
3775 else if (data.passed_pointer || use_register_for_decl (parm))
3776 assign_parm_setup_reg (&all, parm, &data);
3777 else
3778 assign_parm_setup_stack (&all, parm, &data);
3781 if (cfun->stdarg && !DECL_CHAIN (parm))
3783 int pretend_bytes = 0;
3785 assign_parms_setup_varargs (&all, &data, false);
3787 if (chkp_function_instrumented_p (fndecl))
3789 /* We expect this is the last parm. Otherwise it is wrong
3790 to assign bounds right now. */
3791 gcc_assert (i == (fnargs.length () - 1));
3792 assign_bounds (bndargs, all, true, false, false);
3793 targetm.calls.setup_incoming_vararg_bounds (all.args_so_far,
3794 data.promoted_mode,
3795 data.passed_type,
3796 &pretend_bytes,
3797 false);
3798 assign_bounds (bndargs, all, false, true, true);
3799 bndargs.release ();
3803 /* Update info on where next arg arrives in registers. */
3804 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3805 data.passed_type, data.named_arg);
3807 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3808 bound_no++;
3811 assign_bounds (bndargs, all, true, true, true);
3812 bndargs.release ();
3814 if (targetm.calls.split_complex_arg)
3815 assign_parms_unsplit_complex (&all, fnargs);
3817 fnargs.release ();
3819 /* Output all parameter conversion instructions (possibly including calls)
3820 now that all parameters have been copied out of hard registers. */
3821 emit_insn (all.first_conversion_insn);
3823 /* Estimate reload stack alignment from scalar return mode. */
3824 if (SUPPORTS_STACK_ALIGNMENT)
3826 if (DECL_RESULT (fndecl))
3828 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3829 machine_mode mode = TYPE_MODE (type);
3831 if (mode != BLKmode
3832 && mode != VOIDmode
3833 && !AGGREGATE_TYPE_P (type))
3835 unsigned int align = GET_MODE_ALIGNMENT (mode);
3836 if (crtl->stack_alignment_estimated < align)
3838 gcc_assert (!crtl->stack_realign_processed);
3839 crtl->stack_alignment_estimated = align;
3845 /* If we are receiving a struct value address as the first argument, set up
3846 the RTL for the function result. As this might require code to convert
3847 the transmitted address to Pmode, we do this here to ensure that possible
3848 preliminary conversions of the address have been emitted already. */
3849 if (all.function_result_decl)
3851 tree result = DECL_RESULT (current_function_decl);
3852 rtx addr = DECL_RTL (all.function_result_decl);
3853 rtx x;
3855 if (DECL_BY_REFERENCE (result))
3857 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3858 x = addr;
3860 else
3862 SET_DECL_VALUE_EXPR (result,
3863 build1 (INDIRECT_REF, TREE_TYPE (result),
3864 all.function_result_decl));
3865 addr = convert_memory_address (Pmode, addr);
3866 x = gen_rtx_MEM (DECL_MODE (result), addr);
3867 set_mem_attributes (x, result, 1);
3870 DECL_HAS_VALUE_EXPR_P (result) = 1;
3872 set_parm_rtl (result, x);
3875 /* We have aligned all the args, so add space for the pretend args. */
3876 crtl->args.pretend_args_size = all.pretend_args_size;
3877 all.stack_args_size.constant += all.extra_pretend_bytes;
3878 crtl->args.size = all.stack_args_size.constant;
3880 /* Adjust function incoming argument size for alignment and
3881 minimum length. */
3883 crtl->args.size = MAX (crtl->args.size, all.reg_parm_stack_space);
3884 crtl->args.size = CEIL_ROUND (crtl->args.size,
3885 PARM_BOUNDARY / BITS_PER_UNIT);
3887 if (ARGS_GROW_DOWNWARD)
3889 crtl->args.arg_offset_rtx
3890 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3891 : expand_expr (size_diffop (all.stack_args_size.var,
3892 size_int (-all.stack_args_size.constant)),
3893 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3895 else
3896 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3898 /* See how many bytes, if any, of its args a function should try to pop
3899 on return. */
3901 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3902 TREE_TYPE (fndecl),
3903 crtl->args.size);
3905 /* For stdarg.h function, save info about
3906 regs and stack space used by the named args. */
3908 crtl->args.info = all.args_so_far_v;
3910 /* Set the rtx used for the function return value. Put this in its
3911 own variable so any optimizers that need this information don't have
3912 to include tree.h. Do this here so it gets done when an inlined
3913 function gets output. */
3915 crtl->return_rtx
3916 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3917 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3919 /* If scalar return value was computed in a pseudo-reg, or was a named
3920 return value that got dumped to the stack, copy that to the hard
3921 return register. */
3922 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3924 tree decl_result = DECL_RESULT (fndecl);
3925 rtx decl_rtl = DECL_RTL (decl_result);
3927 if (REG_P (decl_rtl)
3928 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3929 : DECL_REGISTER (decl_result))
3931 rtx real_decl_rtl;
3933 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3934 fndecl, true);
3935 if (chkp_function_instrumented_p (fndecl))
3936 crtl->return_bnd
3937 = targetm.calls.chkp_function_value_bounds (TREE_TYPE (decl_result),
3938 fndecl, true);
3939 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3940 /* The delay slot scheduler assumes that crtl->return_rtx
3941 holds the hard register containing the return value, not a
3942 temporary pseudo. */
3943 crtl->return_rtx = real_decl_rtl;
3948 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3949 For all seen types, gimplify their sizes. */
3951 static tree
3952 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3954 tree t = *tp;
3956 *walk_subtrees = 0;
3957 if (TYPE_P (t))
3959 if (POINTER_TYPE_P (t))
3960 *walk_subtrees = 1;
3961 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3962 && !TYPE_SIZES_GIMPLIFIED (t))
3964 gimplify_type_sizes (t, (gimple_seq *) data);
3965 *walk_subtrees = 1;
3969 return NULL;
3972 /* Gimplify the parameter list for current_function_decl. This involves
3973 evaluating SAVE_EXPRs of variable sized parameters and generating code
3974 to implement callee-copies reference parameters. Returns a sequence of
3975 statements to add to the beginning of the function. */
3977 gimple_seq
3978 gimplify_parameters (void)
3980 struct assign_parm_data_all all;
3981 tree parm;
3982 gimple_seq stmts = NULL;
3983 vec<tree> fnargs;
3984 unsigned i;
3986 assign_parms_initialize_all (&all);
3987 fnargs = assign_parms_augmented_arg_list (&all);
3989 FOR_EACH_VEC_ELT (fnargs, i, parm)
3991 struct assign_parm_data_one data;
3993 /* Extract the type of PARM; adjust it according to ABI. */
3994 assign_parm_find_data_types (&all, parm, &data);
3996 /* Early out for errors and void parameters. */
3997 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3998 continue;
4000 /* Update info on where next arg arrives in registers. */
4001 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
4002 data.passed_type, data.named_arg);
4004 /* ??? Once upon a time variable_size stuffed parameter list
4005 SAVE_EXPRs (amongst others) onto a pending sizes list. This
4006 turned out to be less than manageable in the gimple world.
4007 Now we have to hunt them down ourselves. */
4008 walk_tree_without_duplicates (&data.passed_type,
4009 gimplify_parm_type, &stmts);
4011 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
4013 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
4014 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
4017 if (data.passed_pointer)
4019 tree type = TREE_TYPE (data.passed_type);
4020 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
4021 type, data.named_arg))
4023 tree local, t;
4025 /* For constant-sized objects, this is trivial; for
4026 variable-sized objects, we have to play games. */
4027 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
4028 && !(flag_stack_check == GENERIC_STACK_CHECK
4029 && compare_tree_int (DECL_SIZE_UNIT (parm),
4030 STACK_CHECK_MAX_VAR_SIZE) > 0))
4032 local = create_tmp_var (type, get_name (parm));
4033 DECL_IGNORED_P (local) = 0;
4034 /* If PARM was addressable, move that flag over
4035 to the local copy, as its address will be taken,
4036 not the PARMs. Keep the parms address taken
4037 as we'll query that flag during gimplification. */
4038 if (TREE_ADDRESSABLE (parm))
4039 TREE_ADDRESSABLE (local) = 1;
4040 else if (TREE_CODE (type) == COMPLEX_TYPE
4041 || TREE_CODE (type) == VECTOR_TYPE)
4042 DECL_GIMPLE_REG_P (local) = 1;
4044 else
4046 tree ptr_type, addr;
4048 ptr_type = build_pointer_type (type);
4049 addr = create_tmp_reg (ptr_type, get_name (parm));
4050 DECL_IGNORED_P (addr) = 0;
4051 local = build_fold_indirect_ref (addr);
4053 t = builtin_decl_explicit (BUILT_IN_ALLOCA_WITH_ALIGN);
4054 t = build_call_expr (t, 2, DECL_SIZE_UNIT (parm),
4055 size_int (DECL_ALIGN (parm)));
4057 /* The call has been built for a variable-sized object. */
4058 CALL_ALLOCA_FOR_VAR_P (t) = 1;
4059 t = fold_convert (ptr_type, t);
4060 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
4061 gimplify_and_add (t, &stmts);
4064 gimplify_assign (local, parm, &stmts);
4066 SET_DECL_VALUE_EXPR (parm, local);
4067 DECL_HAS_VALUE_EXPR_P (parm) = 1;
4072 fnargs.release ();
4074 return stmts;
4077 /* Compute the size and offset from the start of the stacked arguments for a
4078 parm passed in mode PASSED_MODE and with type TYPE.
4080 INITIAL_OFFSET_PTR points to the current offset into the stacked
4081 arguments.
4083 The starting offset and size for this parm are returned in
4084 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
4085 nonzero, the offset is that of stack slot, which is returned in
4086 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
4087 padding required from the initial offset ptr to the stack slot.
4089 IN_REGS is nonzero if the argument will be passed in registers. It will
4090 never be set if REG_PARM_STACK_SPACE is not defined.
4092 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
4093 for arguments which are passed in registers.
4095 FNDECL is the function in which the argument was defined.
4097 There are two types of rounding that are done. The first, controlled by
4098 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
4099 argument list to be aligned to the specific boundary (in bits). This
4100 rounding affects the initial and starting offsets, but not the argument
4101 size.
4103 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
4104 optionally rounds the size of the parm to PARM_BOUNDARY. The
4105 initial offset is not affected by this rounding, while the size always
4106 is and the starting offset may be. */
4108 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
4109 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
4110 callers pass in the total size of args so far as
4111 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
4113 void
4114 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
4115 int reg_parm_stack_space, int partial,
4116 tree fndecl ATTRIBUTE_UNUSED,
4117 struct args_size *initial_offset_ptr,
4118 struct locate_and_pad_arg_data *locate)
4120 tree sizetree;
4121 enum direction where_pad;
4122 unsigned int boundary, round_boundary;
4123 int part_size_in_regs;
4125 /* If we have found a stack parm before we reach the end of the
4126 area reserved for registers, skip that area. */
4127 if (! in_regs)
4129 if (reg_parm_stack_space > 0)
4131 if (initial_offset_ptr->var)
4133 initial_offset_ptr->var
4134 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
4135 ssize_int (reg_parm_stack_space));
4136 initial_offset_ptr->constant = 0;
4138 else if (initial_offset_ptr->constant < reg_parm_stack_space)
4139 initial_offset_ptr->constant = reg_parm_stack_space;
4143 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
4145 sizetree
4146 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
4147 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
4148 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
4149 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
4150 type);
4151 locate->where_pad = where_pad;
4153 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4154 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
4155 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
4157 locate->boundary = boundary;
4159 if (SUPPORTS_STACK_ALIGNMENT)
4161 /* stack_alignment_estimated can't change after stack has been
4162 realigned. */
4163 if (crtl->stack_alignment_estimated < boundary)
4165 if (!crtl->stack_realign_processed)
4166 crtl->stack_alignment_estimated = boundary;
4167 else
4169 /* If stack is realigned and stack alignment value
4170 hasn't been finalized, it is OK not to increase
4171 stack_alignment_estimated. The bigger alignment
4172 requirement is recorded in stack_alignment_needed
4173 below. */
4174 gcc_assert (!crtl->stack_realign_finalized
4175 && crtl->stack_realign_needed);
4180 /* Remember if the outgoing parameter requires extra alignment on the
4181 calling function side. */
4182 if (crtl->stack_alignment_needed < boundary)
4183 crtl->stack_alignment_needed = boundary;
4184 if (crtl->preferred_stack_boundary < boundary)
4185 crtl->preferred_stack_boundary = boundary;
4187 if (ARGS_GROW_DOWNWARD)
4189 locate->slot_offset.constant = -initial_offset_ptr->constant;
4190 if (initial_offset_ptr->var)
4191 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4192 initial_offset_ptr->var);
4195 tree s2 = sizetree;
4196 if (where_pad != none
4197 && (!tree_fits_uhwi_p (sizetree)
4198 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4199 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4200 SUB_PARM_SIZE (locate->slot_offset, s2);
4203 locate->slot_offset.constant += part_size_in_regs;
4205 if (!in_regs || reg_parm_stack_space > 0)
4206 pad_to_arg_alignment (&locate->slot_offset, boundary,
4207 &locate->alignment_pad);
4209 locate->size.constant = (-initial_offset_ptr->constant
4210 - locate->slot_offset.constant);
4211 if (initial_offset_ptr->var)
4212 locate->size.var = size_binop (MINUS_EXPR,
4213 size_binop (MINUS_EXPR,
4214 ssize_int (0),
4215 initial_offset_ptr->var),
4216 locate->slot_offset.var);
4218 /* Pad_below needs the pre-rounded size to know how much to pad
4219 below. */
4220 locate->offset = locate->slot_offset;
4221 if (where_pad == downward)
4222 pad_below (&locate->offset, passed_mode, sizetree);
4225 else
4227 if (!in_regs || reg_parm_stack_space > 0)
4228 pad_to_arg_alignment (initial_offset_ptr, boundary,
4229 &locate->alignment_pad);
4230 locate->slot_offset = *initial_offset_ptr;
4232 #ifdef PUSH_ROUNDING
4233 if (passed_mode != BLKmode)
4234 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4235 #endif
4237 /* Pad_below needs the pre-rounded size to know how much to pad below
4238 so this must be done before rounding up. */
4239 locate->offset = locate->slot_offset;
4240 if (where_pad == downward)
4241 pad_below (&locate->offset, passed_mode, sizetree);
4243 if (where_pad != none
4244 && (!tree_fits_uhwi_p (sizetree)
4245 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4246 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4248 ADD_PARM_SIZE (locate->size, sizetree);
4250 locate->size.constant -= part_size_in_regs;
4253 #ifdef FUNCTION_ARG_OFFSET
4254 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
4255 #endif
4258 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4259 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4261 static void
4262 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4263 struct args_size *alignment_pad)
4265 tree save_var = NULL_TREE;
4266 HOST_WIDE_INT save_constant = 0;
4267 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4268 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
4270 #ifdef SPARC_STACK_BOUNDARY_HACK
4271 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4272 the real alignment of %sp. However, when it does this, the
4273 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4274 if (SPARC_STACK_BOUNDARY_HACK)
4275 sp_offset = 0;
4276 #endif
4278 if (boundary > PARM_BOUNDARY)
4280 save_var = offset_ptr->var;
4281 save_constant = offset_ptr->constant;
4284 alignment_pad->var = NULL_TREE;
4285 alignment_pad->constant = 0;
4287 if (boundary > BITS_PER_UNIT)
4289 if (offset_ptr->var)
4291 tree sp_offset_tree = ssize_int (sp_offset);
4292 tree offset = size_binop (PLUS_EXPR,
4293 ARGS_SIZE_TREE (*offset_ptr),
4294 sp_offset_tree);
4295 tree rounded;
4296 if (ARGS_GROW_DOWNWARD)
4297 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4298 else
4299 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4301 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4302 /* ARGS_SIZE_TREE includes constant term. */
4303 offset_ptr->constant = 0;
4304 if (boundary > PARM_BOUNDARY)
4305 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4306 save_var);
4308 else
4310 offset_ptr->constant = -sp_offset +
4311 (ARGS_GROW_DOWNWARD
4312 ? FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes)
4313 : CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes));
4315 if (boundary > PARM_BOUNDARY)
4316 alignment_pad->constant = offset_ptr->constant - save_constant;
4321 static void
4322 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4324 unsigned int align = PARM_BOUNDARY / BITS_PER_UNIT;
4325 if (passed_mode != BLKmode)
4326 offset_ptr->constant += -GET_MODE_SIZE (passed_mode) & (align - 1);
4327 else
4329 if (TREE_CODE (sizetree) != INTEGER_CST
4330 || (TREE_INT_CST_LOW (sizetree) & (align - 1)) != 0)
4332 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4333 tree s2 = round_up (sizetree, align);
4334 /* Add it in. */
4335 ADD_PARM_SIZE (*offset_ptr, s2);
4336 SUB_PARM_SIZE (*offset_ptr, sizetree);
4342 /* True if register REGNO was alive at a place where `setjmp' was
4343 called and was set more than once or is an argument. Such regs may
4344 be clobbered by `longjmp'. */
4346 static bool
4347 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4349 /* There appear to be cases where some local vars never reach the
4350 backend but have bogus regnos. */
4351 if (regno >= max_reg_num ())
4352 return false;
4354 return ((REG_N_SETS (regno) > 1
4355 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4356 regno))
4357 && REGNO_REG_SET_P (setjmp_crosses, regno));
4360 /* Walk the tree of blocks describing the binding levels within a
4361 function and warn about variables the might be killed by setjmp or
4362 vfork. This is done after calling flow_analysis before register
4363 allocation since that will clobber the pseudo-regs to hard
4364 regs. */
4366 static void
4367 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4369 tree decl, sub;
4371 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4373 if (VAR_P (decl)
4374 && DECL_RTL_SET_P (decl)
4375 && REG_P (DECL_RTL (decl))
4376 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4377 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4378 " %<longjmp%> or %<vfork%>", decl);
4381 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4382 setjmp_vars_warning (setjmp_crosses, sub);
4385 /* Do the appropriate part of setjmp_vars_warning
4386 but for arguments instead of local variables. */
4388 static void
4389 setjmp_args_warning (bitmap setjmp_crosses)
4391 tree decl;
4392 for (decl = DECL_ARGUMENTS (current_function_decl);
4393 decl; decl = DECL_CHAIN (decl))
4394 if (DECL_RTL (decl) != 0
4395 && REG_P (DECL_RTL (decl))
4396 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4397 warning (OPT_Wclobbered,
4398 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4399 decl);
4402 /* Generate warning messages for variables live across setjmp. */
4404 void
4405 generate_setjmp_warnings (void)
4407 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4409 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4410 || bitmap_empty_p (setjmp_crosses))
4411 return;
4413 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4414 setjmp_args_warning (setjmp_crosses);
4418 /* Reverse the order of elements in the fragment chain T of blocks,
4419 and return the new head of the chain (old last element).
4420 In addition to that clear BLOCK_SAME_RANGE flags when needed
4421 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4422 its super fragment origin. */
4424 static tree
4425 block_fragments_nreverse (tree t)
4427 tree prev = 0, block, next, prev_super = 0;
4428 tree super = BLOCK_SUPERCONTEXT (t);
4429 if (BLOCK_FRAGMENT_ORIGIN (super))
4430 super = BLOCK_FRAGMENT_ORIGIN (super);
4431 for (block = t; block; block = next)
4433 next = BLOCK_FRAGMENT_CHAIN (block);
4434 BLOCK_FRAGMENT_CHAIN (block) = prev;
4435 if ((prev && !BLOCK_SAME_RANGE (prev))
4436 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4437 != prev_super))
4438 BLOCK_SAME_RANGE (block) = 0;
4439 prev_super = BLOCK_SUPERCONTEXT (block);
4440 BLOCK_SUPERCONTEXT (block) = super;
4441 prev = block;
4443 t = BLOCK_FRAGMENT_ORIGIN (t);
4444 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4445 != prev_super)
4446 BLOCK_SAME_RANGE (t) = 0;
4447 BLOCK_SUPERCONTEXT (t) = super;
4448 return prev;
4451 /* Reverse the order of elements in the chain T of blocks,
4452 and return the new head of the chain (old last element).
4453 Also do the same on subblocks and reverse the order of elements
4454 in BLOCK_FRAGMENT_CHAIN as well. */
4456 static tree
4457 blocks_nreverse_all (tree t)
4459 tree prev = 0, block, next;
4460 for (block = t; block; block = next)
4462 next = BLOCK_CHAIN (block);
4463 BLOCK_CHAIN (block) = prev;
4464 if (BLOCK_FRAGMENT_CHAIN (block)
4465 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4467 BLOCK_FRAGMENT_CHAIN (block)
4468 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4469 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4470 BLOCK_SAME_RANGE (block) = 0;
4472 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4473 prev = block;
4475 return prev;
4479 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4480 and create duplicate blocks. */
4481 /* ??? Need an option to either create block fragments or to create
4482 abstract origin duplicates of a source block. It really depends
4483 on what optimization has been performed. */
4485 void
4486 reorder_blocks (void)
4488 tree block = DECL_INITIAL (current_function_decl);
4490 if (block == NULL_TREE)
4491 return;
4493 auto_vec<tree, 10> block_stack;
4495 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4496 clear_block_marks (block);
4498 /* Prune the old trees away, so that they don't get in the way. */
4499 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4500 BLOCK_CHAIN (block) = NULL_TREE;
4502 /* Recreate the block tree from the note nesting. */
4503 reorder_blocks_1 (get_insns (), block, &block_stack);
4504 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4507 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4509 void
4510 clear_block_marks (tree block)
4512 while (block)
4514 TREE_ASM_WRITTEN (block) = 0;
4515 clear_block_marks (BLOCK_SUBBLOCKS (block));
4516 block = BLOCK_CHAIN (block);
4520 static void
4521 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4522 vec<tree> *p_block_stack)
4524 rtx_insn *insn;
4525 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4527 for (insn = insns; insn; insn = NEXT_INSN (insn))
4529 if (NOTE_P (insn))
4531 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4533 tree block = NOTE_BLOCK (insn);
4534 tree origin;
4536 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4537 origin = block;
4539 if (prev_end)
4540 BLOCK_SAME_RANGE (prev_end) = 0;
4541 prev_end = NULL_TREE;
4543 /* If we have seen this block before, that means it now
4544 spans multiple address regions. Create a new fragment. */
4545 if (TREE_ASM_WRITTEN (block))
4547 tree new_block = copy_node (block);
4549 BLOCK_SAME_RANGE (new_block) = 0;
4550 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4551 BLOCK_FRAGMENT_CHAIN (new_block)
4552 = BLOCK_FRAGMENT_CHAIN (origin);
4553 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4555 NOTE_BLOCK (insn) = new_block;
4556 block = new_block;
4559 if (prev_beg == current_block && prev_beg)
4560 BLOCK_SAME_RANGE (block) = 1;
4562 prev_beg = origin;
4564 BLOCK_SUBBLOCKS (block) = 0;
4565 TREE_ASM_WRITTEN (block) = 1;
4566 /* When there's only one block for the entire function,
4567 current_block == block and we mustn't do this, it
4568 will cause infinite recursion. */
4569 if (block != current_block)
4571 tree super;
4572 if (block != origin)
4573 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4574 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4575 (origin))
4576 == current_block);
4577 if (p_block_stack->is_empty ())
4578 super = current_block;
4579 else
4581 super = p_block_stack->last ();
4582 gcc_assert (super == current_block
4583 || BLOCK_FRAGMENT_ORIGIN (super)
4584 == current_block);
4586 BLOCK_SUPERCONTEXT (block) = super;
4587 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4588 BLOCK_SUBBLOCKS (current_block) = block;
4589 current_block = origin;
4591 p_block_stack->safe_push (block);
4593 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4595 NOTE_BLOCK (insn) = p_block_stack->pop ();
4596 current_block = BLOCK_SUPERCONTEXT (current_block);
4597 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4598 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4599 prev_beg = NULL_TREE;
4600 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4601 ? NOTE_BLOCK (insn) : NULL_TREE;
4604 else
4606 prev_beg = NULL_TREE;
4607 if (prev_end)
4608 BLOCK_SAME_RANGE (prev_end) = 0;
4609 prev_end = NULL_TREE;
4614 /* Reverse the order of elements in the chain T of blocks,
4615 and return the new head of the chain (old last element). */
4617 tree
4618 blocks_nreverse (tree t)
4620 tree prev = 0, block, next;
4621 for (block = t; block; block = next)
4623 next = BLOCK_CHAIN (block);
4624 BLOCK_CHAIN (block) = prev;
4625 prev = block;
4627 return prev;
4630 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4631 by modifying the last node in chain 1 to point to chain 2. */
4633 tree
4634 block_chainon (tree op1, tree op2)
4636 tree t1;
4638 if (!op1)
4639 return op2;
4640 if (!op2)
4641 return op1;
4643 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4644 continue;
4645 BLOCK_CHAIN (t1) = op2;
4647 #ifdef ENABLE_TREE_CHECKING
4649 tree t2;
4650 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4651 gcc_assert (t2 != t1);
4653 #endif
4655 return op1;
4658 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4659 non-NULL, list them all into VECTOR, in a depth-first preorder
4660 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4661 blocks. */
4663 static int
4664 all_blocks (tree block, tree *vector)
4666 int n_blocks = 0;
4668 while (block)
4670 TREE_ASM_WRITTEN (block) = 0;
4672 /* Record this block. */
4673 if (vector)
4674 vector[n_blocks] = block;
4676 ++n_blocks;
4678 /* Record the subblocks, and their subblocks... */
4679 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4680 vector ? vector + n_blocks : 0);
4681 block = BLOCK_CHAIN (block);
4684 return n_blocks;
4687 /* Return a vector containing all the blocks rooted at BLOCK. The
4688 number of elements in the vector is stored in N_BLOCKS_P. The
4689 vector is dynamically allocated; it is the caller's responsibility
4690 to call `free' on the pointer returned. */
4692 static tree *
4693 get_block_vector (tree block, int *n_blocks_p)
4695 tree *block_vector;
4697 *n_blocks_p = all_blocks (block, NULL);
4698 block_vector = XNEWVEC (tree, *n_blocks_p);
4699 all_blocks (block, block_vector);
4701 return block_vector;
4704 static GTY(()) int next_block_index = 2;
4706 /* Set BLOCK_NUMBER for all the blocks in FN. */
4708 void
4709 number_blocks (tree fn)
4711 int i;
4712 int n_blocks;
4713 tree *block_vector;
4715 /* For SDB and XCOFF debugging output, we start numbering the blocks
4716 from 1 within each function, rather than keeping a running
4717 count. */
4718 #if SDB_DEBUGGING_INFO || defined (XCOFF_DEBUGGING_INFO)
4719 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
4720 next_block_index = 1;
4721 #endif
4723 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4725 /* The top-level BLOCK isn't numbered at all. */
4726 for (i = 1; i < n_blocks; ++i)
4727 /* We number the blocks from two. */
4728 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4730 free (block_vector);
4732 return;
4735 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4737 DEBUG_FUNCTION tree
4738 debug_find_var_in_block_tree (tree var, tree block)
4740 tree t;
4742 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4743 if (t == var)
4744 return block;
4746 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4748 tree ret = debug_find_var_in_block_tree (var, t);
4749 if (ret)
4750 return ret;
4753 return NULL_TREE;
4756 /* Keep track of whether we're in a dummy function context. If we are,
4757 we don't want to invoke the set_current_function hook, because we'll
4758 get into trouble if the hook calls target_reinit () recursively or
4759 when the initial initialization is not yet complete. */
4761 static bool in_dummy_function;
4763 /* Invoke the target hook when setting cfun. Update the optimization options
4764 if the function uses different options than the default. */
4766 static void
4767 invoke_set_current_function_hook (tree fndecl)
4769 if (!in_dummy_function)
4771 tree opts = ((fndecl)
4772 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4773 : optimization_default_node);
4775 if (!opts)
4776 opts = optimization_default_node;
4778 /* Change optimization options if needed. */
4779 if (optimization_current_node != opts)
4781 optimization_current_node = opts;
4782 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4785 targetm.set_current_function (fndecl);
4786 this_fn_optabs = this_target_optabs;
4788 if (opts != optimization_default_node)
4790 init_tree_optimization_optabs (opts);
4791 if (TREE_OPTIMIZATION_OPTABS (opts))
4792 this_fn_optabs = (struct target_optabs *)
4793 TREE_OPTIMIZATION_OPTABS (opts);
4798 /* cfun should never be set directly; use this function. */
4800 void
4801 set_cfun (struct function *new_cfun, bool force)
4803 if (cfun != new_cfun || force)
4805 cfun = new_cfun;
4806 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4807 redirect_edge_var_map_empty ();
4811 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4813 static vec<function *> cfun_stack;
4815 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4816 current_function_decl accordingly. */
4818 void
4819 push_cfun (struct function *new_cfun)
4821 gcc_assert ((!cfun && !current_function_decl)
4822 || (cfun && current_function_decl == cfun->decl));
4823 cfun_stack.safe_push (cfun);
4824 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4825 set_cfun (new_cfun);
4828 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4830 void
4831 pop_cfun (void)
4833 struct function *new_cfun = cfun_stack.pop ();
4834 /* When in_dummy_function, we do have a cfun but current_function_decl is
4835 NULL. We also allow pushing NULL cfun and subsequently changing
4836 current_function_decl to something else and have both restored by
4837 pop_cfun. */
4838 gcc_checking_assert (in_dummy_function
4839 || !cfun
4840 || current_function_decl == cfun->decl);
4841 set_cfun (new_cfun);
4842 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4845 /* Return value of funcdef and increase it. */
4847 get_next_funcdef_no (void)
4849 return funcdef_no++;
4852 /* Return value of funcdef. */
4854 get_last_funcdef_no (void)
4856 return funcdef_no;
4859 /* Allocate a function structure for FNDECL and set its contents
4860 to the defaults. Set cfun to the newly-allocated object.
4861 Some of the helper functions invoked during initialization assume
4862 that cfun has already been set. Therefore, assign the new object
4863 directly into cfun and invoke the back end hook explicitly at the
4864 very end, rather than initializing a temporary and calling set_cfun
4865 on it.
4867 ABSTRACT_P is true if this is a function that will never be seen by
4868 the middle-end. Such functions are front-end concepts (like C++
4869 function templates) that do not correspond directly to functions
4870 placed in object files. */
4872 void
4873 allocate_struct_function (tree fndecl, bool abstract_p)
4875 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4877 cfun = ggc_cleared_alloc<function> ();
4879 init_eh_for_function ();
4881 if (init_machine_status)
4882 cfun->machine = (*init_machine_status) ();
4884 #ifdef OVERRIDE_ABI_FORMAT
4885 OVERRIDE_ABI_FORMAT (fndecl);
4886 #endif
4888 if (fndecl != NULL_TREE)
4890 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4891 cfun->decl = fndecl;
4892 current_function_funcdef_no = get_next_funcdef_no ();
4895 invoke_set_current_function_hook (fndecl);
4897 if (fndecl != NULL_TREE)
4899 tree result = DECL_RESULT (fndecl);
4901 if (!abstract_p)
4903 /* Now that we have activated any function-specific attributes
4904 that might affect layout, particularly vector modes, relayout
4905 each of the parameters and the result. */
4906 relayout_decl (result);
4907 for (tree parm = DECL_ARGUMENTS (fndecl); parm;
4908 parm = DECL_CHAIN (parm))
4909 relayout_decl (parm);
4911 /* Similarly relayout the function decl. */
4912 targetm.target_option.relayout_function (fndecl);
4915 if (!abstract_p && aggregate_value_p (result, fndecl))
4917 #ifdef PCC_STATIC_STRUCT_RETURN
4918 cfun->returns_pcc_struct = 1;
4919 #endif
4920 cfun->returns_struct = 1;
4923 cfun->stdarg = stdarg_p (fntype);
4925 /* Assume all registers in stdarg functions need to be saved. */
4926 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4927 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4929 /* ??? This could be set on a per-function basis by the front-end
4930 but is this worth the hassle? */
4931 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4932 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4934 if (!profile_flag && !flag_instrument_function_entry_exit)
4935 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4939 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4940 instead of just setting it. */
4942 void
4943 push_struct_function (tree fndecl)
4945 /* When in_dummy_function we might be in the middle of a pop_cfun and
4946 current_function_decl and cfun may not match. */
4947 gcc_assert (in_dummy_function
4948 || (!cfun && !current_function_decl)
4949 || (cfun && current_function_decl == cfun->decl));
4950 cfun_stack.safe_push (cfun);
4951 current_function_decl = fndecl;
4952 allocate_struct_function (fndecl, false);
4955 /* Reset crtl and other non-struct-function variables to defaults as
4956 appropriate for emitting rtl at the start of a function. */
4958 static void
4959 prepare_function_start (void)
4961 gcc_assert (!get_last_insn ());
4962 init_temp_slots ();
4963 init_emit ();
4964 init_varasm_status ();
4965 init_expr ();
4966 default_rtl_profile ();
4968 if (flag_stack_usage_info)
4970 cfun->su = ggc_cleared_alloc<stack_usage> ();
4971 cfun->su->static_stack_size = -1;
4974 cse_not_expected = ! optimize;
4976 /* Caller save not needed yet. */
4977 caller_save_needed = 0;
4979 /* We haven't done register allocation yet. */
4980 reg_renumber = 0;
4982 /* Indicate that we have not instantiated virtual registers yet. */
4983 virtuals_instantiated = 0;
4985 /* Indicate that we want CONCATs now. */
4986 generating_concat_p = 1;
4988 /* Indicate we have no need of a frame pointer yet. */
4989 frame_pointer_needed = 0;
4992 void
4993 push_dummy_function (bool with_decl)
4995 tree fn_decl, fn_type, fn_result_decl;
4997 gcc_assert (!in_dummy_function);
4998 in_dummy_function = true;
5000 if (with_decl)
5002 fn_type = build_function_type_list (void_type_node, NULL_TREE);
5003 fn_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
5004 fn_type);
5005 fn_result_decl = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
5006 NULL_TREE, void_type_node);
5007 DECL_RESULT (fn_decl) = fn_result_decl;
5009 else
5010 fn_decl = NULL_TREE;
5012 push_struct_function (fn_decl);
5015 /* Initialize the rtl expansion mechanism so that we can do simple things
5016 like generate sequences. This is used to provide a context during global
5017 initialization of some passes. You must call expand_dummy_function_end
5018 to exit this context. */
5020 void
5021 init_dummy_function_start (void)
5023 push_dummy_function (false);
5024 prepare_function_start ();
5027 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
5028 and initialize static variables for generating RTL for the statements
5029 of the function. */
5031 void
5032 init_function_start (tree subr)
5034 /* Initialize backend, if needed. */
5035 initialize_rtl ();
5037 prepare_function_start ();
5038 decide_function_section (subr);
5040 /* Warn if this value is an aggregate type,
5041 regardless of which calling convention we are using for it. */
5042 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
5043 warning (OPT_Waggregate_return, "function returns an aggregate");
5046 /* Expand code to verify the stack_protect_guard. This is invoked at
5047 the end of a function to be protected. */
5049 void
5050 stack_protect_epilogue (void)
5052 tree guard_decl = targetm.stack_protect_guard ();
5053 rtx_code_label *label = gen_label_rtx ();
5054 rtx x, y;
5055 rtx_insn *seq;
5057 x = expand_normal (crtl->stack_protect_guard);
5058 if (guard_decl)
5059 y = expand_normal (guard_decl);
5060 else
5061 y = const0_rtx;
5063 /* Allow the target to compare Y with X without leaking either into
5064 a register. */
5065 if (targetm.have_stack_protect_test ()
5066 && ((seq = targetm.gen_stack_protect_test (x, y, label)) != NULL_RTX))
5067 emit_insn (seq);
5068 else
5069 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
5071 /* The noreturn predictor has been moved to the tree level. The rtl-level
5072 predictors estimate this branch about 20%, which isn't enough to get
5073 things moved out of line. Since this is the only extant case of adding
5074 a noreturn function at the rtl level, it doesn't seem worth doing ought
5075 except adding the prediction by hand. */
5076 rtx_insn *tmp = get_last_insn ();
5077 if (JUMP_P (tmp))
5078 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
5080 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
5081 free_temp_slots ();
5082 emit_label (label);
5085 /* Start the RTL for a new function, and set variables used for
5086 emitting RTL.
5087 SUBR is the FUNCTION_DECL node.
5088 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5089 the function's parameters, which must be run at any return statement. */
5091 void
5092 expand_function_start (tree subr)
5094 /* Make sure volatile mem refs aren't considered
5095 valid operands of arithmetic insns. */
5096 init_recog_no_volatile ();
5098 crtl->profile
5099 = (profile_flag
5100 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
5102 crtl->limit_stack
5103 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
5105 /* Make the label for return statements to jump to. Do not special
5106 case machines with special return instructions -- they will be
5107 handled later during jump, ifcvt, or epilogue creation. */
5108 return_label = gen_label_rtx ();
5110 /* Initialize rtx used to return the value. */
5111 /* Do this before assign_parms so that we copy the struct value address
5112 before any library calls that assign parms might generate. */
5114 /* Decide whether to return the value in memory or in a register. */
5115 tree res = DECL_RESULT (subr);
5116 if (aggregate_value_p (res, subr))
5118 /* Returning something that won't go in a register. */
5119 rtx value_address = 0;
5121 #ifdef PCC_STATIC_STRUCT_RETURN
5122 if (cfun->returns_pcc_struct)
5124 int size = int_size_in_bytes (TREE_TYPE (res));
5125 value_address = assemble_static_space (size);
5127 else
5128 #endif
5130 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
5131 /* Expect to be passed the address of a place to store the value.
5132 If it is passed as an argument, assign_parms will take care of
5133 it. */
5134 if (sv)
5136 value_address = gen_reg_rtx (Pmode);
5137 emit_move_insn (value_address, sv);
5140 if (value_address)
5142 rtx x = value_address;
5143 if (!DECL_BY_REFERENCE (res))
5145 x = gen_rtx_MEM (DECL_MODE (res), x);
5146 set_mem_attributes (x, res, 1);
5148 set_parm_rtl (res, x);
5151 else if (DECL_MODE (res) == VOIDmode)
5152 /* If return mode is void, this decl rtl should not be used. */
5153 set_parm_rtl (res, NULL_RTX);
5154 else
5156 /* Compute the return values into a pseudo reg, which we will copy
5157 into the true return register after the cleanups are done. */
5158 tree return_type = TREE_TYPE (res);
5160 /* If we may coalesce this result, make sure it has the expected mode
5161 in case it was promoted. But we need not bother about BLKmode. */
5162 machine_mode promoted_mode
5163 = flag_tree_coalesce_vars && is_gimple_reg (res)
5164 ? promote_ssa_mode (ssa_default_def (cfun, res), NULL)
5165 : BLKmode;
5167 if (promoted_mode != BLKmode)
5168 set_parm_rtl (res, gen_reg_rtx (promoted_mode));
5169 else if (TYPE_MODE (return_type) != BLKmode
5170 && targetm.calls.return_in_msb (return_type))
5171 /* expand_function_end will insert the appropriate padding in
5172 this case. Use the return value's natural (unpadded) mode
5173 within the function proper. */
5174 set_parm_rtl (res, gen_reg_rtx (TYPE_MODE (return_type)));
5175 else
5177 /* In order to figure out what mode to use for the pseudo, we
5178 figure out what the mode of the eventual return register will
5179 actually be, and use that. */
5180 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
5182 /* Structures that are returned in registers are not
5183 aggregate_value_p, so we may see a PARALLEL or a REG. */
5184 if (REG_P (hard_reg))
5185 set_parm_rtl (res, gen_reg_rtx (GET_MODE (hard_reg)));
5186 else
5188 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5189 set_parm_rtl (res, gen_group_rtx (hard_reg));
5193 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5194 result to the real return register(s). */
5195 DECL_REGISTER (res) = 1;
5197 if (chkp_function_instrumented_p (current_function_decl))
5199 tree return_type = TREE_TYPE (res);
5200 rtx bounds = targetm.calls.chkp_function_value_bounds (return_type,
5201 subr, 1);
5202 SET_DECL_BOUNDS_RTL (res, bounds);
5206 /* Initialize rtx for parameters and local variables.
5207 In some cases this requires emitting insns. */
5208 assign_parms (subr);
5210 /* If function gets a static chain arg, store it. */
5211 if (cfun->static_chain_decl)
5213 tree parm = cfun->static_chain_decl;
5214 rtx local, chain;
5215 rtx_insn *insn;
5216 int unsignedp;
5218 local = gen_reg_rtx (promote_decl_mode (parm, &unsignedp));
5219 chain = targetm.calls.static_chain (current_function_decl, true);
5221 set_decl_incoming_rtl (parm, chain, false);
5222 set_parm_rtl (parm, local);
5223 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5225 if (GET_MODE (local) != GET_MODE (chain))
5227 convert_move (local, chain, unsignedp);
5228 insn = get_last_insn ();
5230 else
5231 insn = emit_move_insn (local, chain);
5233 /* Mark the register as eliminable, similar to parameters. */
5234 if (MEM_P (chain)
5235 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
5236 set_dst_reg_note (insn, REG_EQUIV, chain, local);
5238 /* If we aren't optimizing, save the static chain onto the stack. */
5239 if (!optimize)
5241 tree saved_static_chain_decl
5242 = build_decl (DECL_SOURCE_LOCATION (parm), VAR_DECL,
5243 DECL_NAME (parm), TREE_TYPE (parm));
5244 rtx saved_static_chain_rtx
5245 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5246 SET_DECL_RTL (saved_static_chain_decl, saved_static_chain_rtx);
5247 emit_move_insn (saved_static_chain_rtx, chain);
5248 SET_DECL_VALUE_EXPR (parm, saved_static_chain_decl);
5249 DECL_HAS_VALUE_EXPR_P (parm) = 1;
5253 /* The following was moved from init_function_start.
5254 The move is supposed to make sdb output more accurate. */
5255 /* Indicate the beginning of the function body,
5256 as opposed to parm setup. */
5257 emit_note (NOTE_INSN_FUNCTION_BEG);
5259 gcc_assert (NOTE_P (get_last_insn ()));
5261 parm_birth_insn = get_last_insn ();
5263 /* If the function receives a non-local goto, then store the
5264 bits we need to restore the frame pointer. */
5265 if (cfun->nonlocal_goto_save_area)
5267 tree t_save;
5268 rtx r_save;
5270 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5271 gcc_assert (DECL_RTL_SET_P (var));
5273 t_save = build4 (ARRAY_REF,
5274 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
5275 cfun->nonlocal_goto_save_area,
5276 integer_zero_node, NULL_TREE, NULL_TREE);
5277 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
5278 gcc_assert (GET_MODE (r_save) == Pmode);
5280 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
5281 update_nonlocal_goto_save_area ();
5284 if (crtl->profile)
5286 #ifdef PROFILE_HOOK
5287 PROFILE_HOOK (current_function_funcdef_no);
5288 #endif
5291 /* If we are doing generic stack checking, the probe should go here. */
5292 if (flag_stack_check == GENERIC_STACK_CHECK)
5293 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
5296 void
5297 pop_dummy_function (void)
5299 pop_cfun ();
5300 in_dummy_function = false;
5303 /* Undo the effects of init_dummy_function_start. */
5304 void
5305 expand_dummy_function_end (void)
5307 gcc_assert (in_dummy_function);
5309 /* End any sequences that failed to be closed due to syntax errors. */
5310 while (in_sequence_p ())
5311 end_sequence ();
5313 /* Outside function body, can't compute type's actual size
5314 until next function's body starts. */
5316 free_after_parsing (cfun);
5317 free_after_compilation (cfun);
5318 pop_dummy_function ();
5321 /* Helper for diddle_return_value. */
5323 void
5324 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5326 if (! outgoing)
5327 return;
5329 if (REG_P (outgoing))
5330 (*doit) (outgoing, arg);
5331 else if (GET_CODE (outgoing) == PARALLEL)
5333 int i;
5335 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5337 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5339 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5340 (*doit) (x, arg);
5345 /* Call DOIT for each hard register used as a return value from
5346 the current function. */
5348 void
5349 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5351 diddle_return_value_1 (doit, arg, crtl->return_bnd);
5352 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5355 static void
5356 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5358 emit_clobber (reg);
5361 void
5362 clobber_return_register (void)
5364 diddle_return_value (do_clobber_return_reg, NULL);
5366 /* In case we do use pseudo to return value, clobber it too. */
5367 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5369 tree decl_result = DECL_RESULT (current_function_decl);
5370 rtx decl_rtl = DECL_RTL (decl_result);
5371 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
5373 do_clobber_return_reg (decl_rtl, NULL);
5378 static void
5379 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5381 emit_use (reg);
5384 static void
5385 use_return_register (void)
5387 diddle_return_value (do_use_return_reg, NULL);
5390 /* Set the location of the insn chain starting at INSN to LOC. */
5392 static void
5393 set_insn_locations (rtx_insn *insn, int loc)
5395 while (insn != NULL)
5397 if (INSN_P (insn))
5398 INSN_LOCATION (insn) = loc;
5399 insn = NEXT_INSN (insn);
5403 /* Generate RTL for the end of the current function. */
5405 void
5406 expand_function_end (void)
5408 /* If arg_pointer_save_area was referenced only from a nested
5409 function, we will not have initialized it yet. Do that now. */
5410 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
5411 get_arg_pointer_save_area ();
5413 /* If we are doing generic stack checking and this function makes calls,
5414 do a stack probe at the start of the function to ensure we have enough
5415 space for another stack frame. */
5416 if (flag_stack_check == GENERIC_STACK_CHECK)
5418 rtx_insn *insn, *seq;
5420 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5421 if (CALL_P (insn))
5423 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
5424 start_sequence ();
5425 if (STACK_CHECK_MOVING_SP)
5426 anti_adjust_stack_and_probe (max_frame_size, true);
5427 else
5428 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
5429 seq = get_insns ();
5430 end_sequence ();
5431 set_insn_locations (seq, prologue_location);
5432 emit_insn_before (seq, stack_check_probe_note);
5433 break;
5437 /* End any sequences that failed to be closed due to syntax errors. */
5438 while (in_sequence_p ())
5439 end_sequence ();
5441 clear_pending_stack_adjust ();
5442 do_pending_stack_adjust ();
5444 /* Output a linenumber for the end of the function.
5445 SDB depends on this. */
5446 set_curr_insn_location (input_location);
5448 /* Before the return label (if any), clobber the return
5449 registers so that they are not propagated live to the rest of
5450 the function. This can only happen with functions that drop
5451 through; if there had been a return statement, there would
5452 have either been a return rtx, or a jump to the return label.
5454 We delay actual code generation after the current_function_value_rtx
5455 is computed. */
5456 rtx_insn *clobber_after = get_last_insn ();
5458 /* Output the label for the actual return from the function. */
5459 emit_label (return_label);
5461 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
5463 /* Let except.c know where it should emit the call to unregister
5464 the function context for sjlj exceptions. */
5465 if (flag_exceptions)
5466 sjlj_emit_function_exit_after (get_last_insn ());
5468 else
5470 /* We want to ensure that instructions that may trap are not
5471 moved into the epilogue by scheduling, because we don't
5472 always emit unwind information for the epilogue. */
5473 if (cfun->can_throw_non_call_exceptions)
5474 emit_insn (gen_blockage ());
5477 /* If this is an implementation of throw, do what's necessary to
5478 communicate between __builtin_eh_return and the epilogue. */
5479 expand_eh_return ();
5481 /* If scalar return value was computed in a pseudo-reg, or was a named
5482 return value that got dumped to the stack, copy that to the hard
5483 return register. */
5484 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5486 tree decl_result = DECL_RESULT (current_function_decl);
5487 rtx decl_rtl = DECL_RTL (decl_result);
5489 if (REG_P (decl_rtl)
5490 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5491 : DECL_REGISTER (decl_result))
5493 rtx real_decl_rtl = crtl->return_rtx;
5495 /* This should be set in assign_parms. */
5496 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5498 /* If this is a BLKmode structure being returned in registers,
5499 then use the mode computed in expand_return. Note that if
5500 decl_rtl is memory, then its mode may have been changed,
5501 but that crtl->return_rtx has not. */
5502 if (GET_MODE (real_decl_rtl) == BLKmode)
5503 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5505 /* If a non-BLKmode return value should be padded at the least
5506 significant end of the register, shift it left by the appropriate
5507 amount. BLKmode results are handled using the group load/store
5508 machinery. */
5509 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5510 && REG_P (real_decl_rtl)
5511 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5513 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5514 REGNO (real_decl_rtl)),
5515 decl_rtl);
5516 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5518 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5520 /* If expand_function_start has created a PARALLEL for decl_rtl,
5521 move the result to the real return registers. Otherwise, do
5522 a group load from decl_rtl for a named return. */
5523 if (GET_CODE (decl_rtl) == PARALLEL)
5524 emit_group_move (real_decl_rtl, decl_rtl);
5525 else
5526 emit_group_load (real_decl_rtl, decl_rtl,
5527 TREE_TYPE (decl_result),
5528 int_size_in_bytes (TREE_TYPE (decl_result)));
5530 /* In the case of complex integer modes smaller than a word, we'll
5531 need to generate some non-trivial bitfield insertions. Do that
5532 on a pseudo and not the hard register. */
5533 else if (GET_CODE (decl_rtl) == CONCAT
5534 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
5535 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
5537 int old_generating_concat_p;
5538 rtx tmp;
5540 old_generating_concat_p = generating_concat_p;
5541 generating_concat_p = 0;
5542 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5543 generating_concat_p = old_generating_concat_p;
5545 emit_move_insn (tmp, decl_rtl);
5546 emit_move_insn (real_decl_rtl, tmp);
5548 /* If a named return value dumped decl_return to memory, then
5549 we may need to re-do the PROMOTE_MODE signed/unsigned
5550 extension. */
5551 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5553 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5554 promote_function_mode (TREE_TYPE (decl_result),
5555 GET_MODE (decl_rtl), &unsignedp,
5556 TREE_TYPE (current_function_decl), 1);
5558 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5560 else
5561 emit_move_insn (real_decl_rtl, decl_rtl);
5565 /* If returning a structure, arrange to return the address of the value
5566 in a place where debuggers expect to find it.
5568 If returning a structure PCC style,
5569 the caller also depends on this value.
5570 And cfun->returns_pcc_struct is not necessarily set. */
5571 if ((cfun->returns_struct || cfun->returns_pcc_struct)
5572 && !targetm.calls.omit_struct_return_reg)
5574 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5575 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5576 rtx outgoing;
5578 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5579 type = TREE_TYPE (type);
5580 else
5581 value_address = XEXP (value_address, 0);
5583 outgoing = targetm.calls.function_value (build_pointer_type (type),
5584 current_function_decl, true);
5586 /* Mark this as a function return value so integrate will delete the
5587 assignment and USE below when inlining this function. */
5588 REG_FUNCTION_VALUE_P (outgoing) = 1;
5590 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5591 scalar_int_mode mode = as_a <scalar_int_mode> (GET_MODE (outgoing));
5592 value_address = convert_memory_address (mode, value_address);
5594 emit_move_insn (outgoing, value_address);
5596 /* Show return register used to hold result (in this case the address
5597 of the result. */
5598 crtl->return_rtx = outgoing;
5601 /* Emit the actual code to clobber return register. Don't emit
5602 it if clobber_after is a barrier, then the previous basic block
5603 certainly doesn't fall thru into the exit block. */
5604 if (!BARRIER_P (clobber_after))
5606 start_sequence ();
5607 clobber_return_register ();
5608 rtx_insn *seq = get_insns ();
5609 end_sequence ();
5611 emit_insn_after (seq, clobber_after);
5614 /* Output the label for the naked return from the function. */
5615 if (naked_return_label)
5616 emit_label (naked_return_label);
5618 /* @@@ This is a kludge. We want to ensure that instructions that
5619 may trap are not moved into the epilogue by scheduling, because
5620 we don't always emit unwind information for the epilogue. */
5621 if (cfun->can_throw_non_call_exceptions
5622 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5623 emit_insn (gen_blockage ());
5625 /* If stack protection is enabled for this function, check the guard. */
5626 if (crtl->stack_protect_guard && targetm.stack_protect_runtime_enabled_p ())
5627 stack_protect_epilogue ();
5629 /* If we had calls to alloca, and this machine needs
5630 an accurate stack pointer to exit the function,
5631 insert some code to save and restore the stack pointer. */
5632 if (! EXIT_IGNORE_STACK
5633 && cfun->calls_alloca)
5635 rtx tem = 0;
5637 start_sequence ();
5638 emit_stack_save (SAVE_FUNCTION, &tem);
5639 rtx_insn *seq = get_insns ();
5640 end_sequence ();
5641 emit_insn_before (seq, parm_birth_insn);
5643 emit_stack_restore (SAVE_FUNCTION, tem);
5646 /* ??? This should no longer be necessary since stupid is no longer with
5647 us, but there are some parts of the compiler (eg reload_combine, and
5648 sh mach_dep_reorg) that still try and compute their own lifetime info
5649 instead of using the general framework. */
5650 use_return_register ();
5654 get_arg_pointer_save_area (void)
5656 rtx ret = arg_pointer_save_area;
5658 if (! ret)
5660 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5661 arg_pointer_save_area = ret;
5664 if (! crtl->arg_pointer_save_area_init)
5666 /* Save the arg pointer at the beginning of the function. The
5667 generated stack slot may not be a valid memory address, so we
5668 have to check it and fix it if necessary. */
5669 start_sequence ();
5670 emit_move_insn (validize_mem (copy_rtx (ret)),
5671 crtl->args.internal_arg_pointer);
5672 rtx_insn *seq = get_insns ();
5673 end_sequence ();
5675 push_topmost_sequence ();
5676 emit_insn_after (seq, entry_of_function ());
5677 pop_topmost_sequence ();
5679 crtl->arg_pointer_save_area_init = true;
5682 return ret;
5685 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5686 for the first time. */
5688 static void
5689 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5691 rtx_insn *tmp;
5692 hash_table<insn_cache_hasher> *hash = *hashp;
5694 if (hash == NULL)
5695 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5697 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5699 rtx *slot = hash->find_slot (tmp, INSERT);
5700 gcc_assert (*slot == NULL);
5701 *slot = tmp;
5705 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5706 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5707 insn, then record COPY as well. */
5709 void
5710 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5712 hash_table<insn_cache_hasher> *hash;
5713 rtx *slot;
5715 hash = epilogue_insn_hash;
5716 if (!hash || !hash->find (insn))
5718 hash = prologue_insn_hash;
5719 if (!hash || !hash->find (insn))
5720 return;
5723 slot = hash->find_slot (copy, INSERT);
5724 gcc_assert (*slot == NULL);
5725 *slot = copy;
5728 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5729 we can be running after reorg, SEQUENCE rtl is possible. */
5731 static bool
5732 contains (const rtx_insn *insn, hash_table<insn_cache_hasher> *hash)
5734 if (hash == NULL)
5735 return false;
5737 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5739 rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn));
5740 int i;
5741 for (i = seq->len () - 1; i >= 0; i--)
5742 if (hash->find (seq->element (i)))
5743 return true;
5744 return false;
5747 return hash->find (const_cast<rtx_insn *> (insn)) != NULL;
5751 prologue_contains (const rtx_insn *insn)
5753 return contains (insn, prologue_insn_hash);
5757 epilogue_contains (const rtx_insn *insn)
5759 return contains (insn, epilogue_insn_hash);
5763 prologue_epilogue_contains (const rtx_insn *insn)
5765 if (contains (insn, prologue_insn_hash))
5766 return 1;
5767 if (contains (insn, epilogue_insn_hash))
5768 return 1;
5769 return 0;
5772 void
5773 record_prologue_seq (rtx_insn *seq)
5775 record_insns (seq, NULL, &prologue_insn_hash);
5778 void
5779 record_epilogue_seq (rtx_insn *seq)
5781 record_insns (seq, NULL, &epilogue_insn_hash);
5784 /* Set JUMP_LABEL for a return insn. */
5786 void
5787 set_return_jump_label (rtx_insn *returnjump)
5789 rtx pat = PATTERN (returnjump);
5790 if (GET_CODE (pat) == PARALLEL)
5791 pat = XVECEXP (pat, 0, 0);
5792 if (ANY_RETURN_P (pat))
5793 JUMP_LABEL (returnjump) = pat;
5794 else
5795 JUMP_LABEL (returnjump) = ret_rtx;
5798 /* Return a sequence to be used as the split prologue for the current
5799 function, or NULL. */
5801 static rtx_insn *
5802 make_split_prologue_seq (void)
5804 if (!flag_split_stack
5805 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl)))
5806 return NULL;
5808 start_sequence ();
5809 emit_insn (targetm.gen_split_stack_prologue ());
5810 rtx_insn *seq = get_insns ();
5811 end_sequence ();
5813 record_insns (seq, NULL, &prologue_insn_hash);
5814 set_insn_locations (seq, prologue_location);
5816 return seq;
5819 /* Return a sequence to be used as the prologue for the current function,
5820 or NULL. */
5822 static rtx_insn *
5823 make_prologue_seq (void)
5825 if (!targetm.have_prologue ())
5826 return NULL;
5828 start_sequence ();
5829 rtx_insn *seq = targetm.gen_prologue ();
5830 emit_insn (seq);
5832 /* Insert an explicit USE for the frame pointer
5833 if the profiling is on and the frame pointer is required. */
5834 if (crtl->profile && frame_pointer_needed)
5835 emit_use (hard_frame_pointer_rtx);
5837 /* Retain a map of the prologue insns. */
5838 record_insns (seq, NULL, &prologue_insn_hash);
5839 emit_note (NOTE_INSN_PROLOGUE_END);
5841 /* Ensure that instructions are not moved into the prologue when
5842 profiling is on. The call to the profiling routine can be
5843 emitted within the live range of a call-clobbered register. */
5844 if (!targetm.profile_before_prologue () && crtl->profile)
5845 emit_insn (gen_blockage ());
5847 seq = get_insns ();
5848 end_sequence ();
5849 set_insn_locations (seq, prologue_location);
5851 return seq;
5854 /* Return a sequence to be used as the epilogue for the current function,
5855 or NULL. */
5857 static rtx_insn *
5858 make_epilogue_seq (void)
5860 if (!targetm.have_epilogue ())
5861 return NULL;
5863 start_sequence ();
5864 emit_note (NOTE_INSN_EPILOGUE_BEG);
5865 rtx_insn *seq = targetm.gen_epilogue ();
5866 if (seq)
5867 emit_jump_insn (seq);
5869 /* Retain a map of the epilogue insns. */
5870 record_insns (seq, NULL, &epilogue_insn_hash);
5871 set_insn_locations (seq, epilogue_location);
5873 seq = get_insns ();
5874 rtx_insn *returnjump = get_last_insn ();
5875 end_sequence ();
5877 if (JUMP_P (returnjump))
5878 set_return_jump_label (returnjump);
5880 return seq;
5884 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5885 this into place with notes indicating where the prologue ends and where
5886 the epilogue begins. Update the basic block information when possible.
5888 Notes on epilogue placement:
5889 There are several kinds of edges to the exit block:
5890 * a single fallthru edge from LAST_BB
5891 * possibly, edges from blocks containing sibcalls
5892 * possibly, fake edges from infinite loops
5894 The epilogue is always emitted on the fallthru edge from the last basic
5895 block in the function, LAST_BB, into the exit block.
5897 If LAST_BB is empty except for a label, it is the target of every
5898 other basic block in the function that ends in a return. If a
5899 target has a return or simple_return pattern (possibly with
5900 conditional variants), these basic blocks can be changed so that a
5901 return insn is emitted into them, and their target is adjusted to
5902 the real exit block.
5904 Notes on shrink wrapping: We implement a fairly conservative
5905 version of shrink-wrapping rather than the textbook one. We only
5906 generate a single prologue and a single epilogue. This is
5907 sufficient to catch a number of interesting cases involving early
5908 exits.
5910 First, we identify the blocks that require the prologue to occur before
5911 them. These are the ones that modify a call-saved register, or reference
5912 any of the stack or frame pointer registers. To simplify things, we then
5913 mark everything reachable from these blocks as also requiring a prologue.
5914 This takes care of loops automatically, and avoids the need to examine
5915 whether MEMs reference the frame, since it is sufficient to check for
5916 occurrences of the stack or frame pointer.
5918 We then compute the set of blocks for which the need for a prologue
5919 is anticipatable (borrowing terminology from the shrink-wrapping
5920 description in Muchnick's book). These are the blocks which either
5921 require a prologue themselves, or those that have only successors
5922 where the prologue is anticipatable. The prologue needs to be
5923 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5924 is not. For the moment, we ensure that only one such edge exists.
5926 The epilogue is placed as described above, but we make a
5927 distinction between inserting return and simple_return patterns
5928 when modifying other blocks that end in a return. Blocks that end
5929 in a sibcall omit the sibcall_epilogue if the block is not in
5930 ANTIC. */
5932 void
5933 thread_prologue_and_epilogue_insns (void)
5935 df_analyze ();
5937 /* Can't deal with multiple successors of the entry block at the
5938 moment. Function should always have at least one entry
5939 point. */
5940 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
5942 edge entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5943 edge orig_entry_edge = entry_edge;
5945 rtx_insn *split_prologue_seq = make_split_prologue_seq ();
5946 rtx_insn *prologue_seq = make_prologue_seq ();
5947 rtx_insn *epilogue_seq = make_epilogue_seq ();
5949 /* Try to perform a kind of shrink-wrapping, making sure the
5950 prologue/epilogue is emitted only around those parts of the
5951 function that require it. */
5952 try_shrink_wrapping (&entry_edge, prologue_seq);
5954 /* If the target can handle splitting the prologue/epilogue into separate
5955 components, try to shrink-wrap these components separately. */
5956 try_shrink_wrapping_separate (entry_edge->dest);
5958 /* If that did anything for any component we now need the generate the
5959 "main" prologue again. Because some targets require some of these
5960 to be called in a specific order (i386 requires the split prologue
5961 to be first, for example), we create all three sequences again here.
5962 If this does not work for some target, that target should not enable
5963 separate shrink-wrapping. */
5964 if (crtl->shrink_wrapped_separate)
5966 split_prologue_seq = make_split_prologue_seq ();
5967 prologue_seq = make_prologue_seq ();
5968 epilogue_seq = make_epilogue_seq ();
5971 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
5973 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5974 this marker for the splits of EH_RETURN patterns, and nothing else
5975 uses the flag in the meantime. */
5976 epilogue_completed = 1;
5978 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5979 some targets, these get split to a special version of the epilogue
5980 code. In order to be able to properly annotate these with unwind
5981 info, try to split them now. If we get a valid split, drop an
5982 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5983 edge e;
5984 edge_iterator ei;
5985 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5987 rtx_insn *prev, *last, *trial;
5989 if (e->flags & EDGE_FALLTHRU)
5990 continue;
5991 last = BB_END (e->src);
5992 if (!eh_returnjump_p (last))
5993 continue;
5995 prev = PREV_INSN (last);
5996 trial = try_split (PATTERN (last), last, 1);
5997 if (trial == last)
5998 continue;
6000 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
6001 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
6004 edge exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6006 if (exit_fallthru_edge)
6008 if (epilogue_seq)
6010 insert_insn_on_edge (epilogue_seq, exit_fallthru_edge);
6011 commit_edge_insertions ();
6013 /* The epilogue insns we inserted may cause the exit edge to no longer
6014 be fallthru. */
6015 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6017 if (((e->flags & EDGE_FALLTHRU) != 0)
6018 && returnjump_p (BB_END (e->src)))
6019 e->flags &= ~EDGE_FALLTHRU;
6022 else if (next_active_insn (BB_END (exit_fallthru_edge->src)))
6024 /* We have a fall-through edge to the exit block, the source is not
6025 at the end of the function, and there will be an assembler epilogue
6026 at the end of the function.
6027 We can't use force_nonfallthru here, because that would try to
6028 use return. Inserting a jump 'by hand' is extremely messy, so
6029 we take advantage of cfg_layout_finalize using
6030 fixup_fallthru_exit_predecessor. */
6031 cfg_layout_initialize (0);
6032 basic_block cur_bb;
6033 FOR_EACH_BB_FN (cur_bb, cfun)
6034 if (cur_bb->index >= NUM_FIXED_BLOCKS
6035 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
6036 cur_bb->aux = cur_bb->next_bb;
6037 cfg_layout_finalize ();
6041 /* Insert the prologue. */
6043 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
6045 if (split_prologue_seq || prologue_seq)
6047 rtx_insn *split_prologue_insn = split_prologue_seq;
6048 if (split_prologue_seq)
6050 while (split_prologue_insn && !NONDEBUG_INSN_P (split_prologue_insn))
6051 split_prologue_insn = NEXT_INSN (split_prologue_insn);
6052 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
6055 rtx_insn *prologue_insn = prologue_seq;
6056 if (prologue_seq)
6058 while (prologue_insn && !NONDEBUG_INSN_P (prologue_insn))
6059 prologue_insn = NEXT_INSN (prologue_insn);
6060 insert_insn_on_edge (prologue_seq, entry_edge);
6063 commit_edge_insertions ();
6065 /* Look for basic blocks within the prologue insns. */
6066 if (split_prologue_insn
6067 && BLOCK_FOR_INSN (split_prologue_insn) == NULL)
6068 split_prologue_insn = NULL;
6069 if (prologue_insn
6070 && BLOCK_FOR_INSN (prologue_insn) == NULL)
6071 prologue_insn = NULL;
6072 if (split_prologue_insn || prologue_insn)
6074 auto_sbitmap blocks (last_basic_block_for_fn (cfun));
6075 bitmap_clear (blocks);
6076 if (split_prologue_insn)
6077 bitmap_set_bit (blocks,
6078 BLOCK_FOR_INSN (split_prologue_insn)->index);
6079 if (prologue_insn)
6080 bitmap_set_bit (blocks, BLOCK_FOR_INSN (prologue_insn)->index);
6081 find_many_sub_basic_blocks (blocks);
6085 default_rtl_profile ();
6087 /* Emit sibling epilogues before any sibling call sites. */
6088 for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
6089 (e = ei_safe_edge (ei));
6090 ei_next (&ei))
6092 /* Skip those already handled, the ones that run without prologue. */
6093 if (e->flags & EDGE_IGNORE)
6095 e->flags &= ~EDGE_IGNORE;
6096 continue;
6099 rtx_insn *insn = BB_END (e->src);
6101 if (!(CALL_P (insn) && SIBLING_CALL_P (insn)))
6102 continue;
6104 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6106 start_sequence ();
6107 emit_note (NOTE_INSN_EPILOGUE_BEG);
6108 emit_insn (ep_seq);
6109 rtx_insn *seq = get_insns ();
6110 end_sequence ();
6112 /* Retain a map of the epilogue insns. Used in life analysis to
6113 avoid getting rid of sibcall epilogue insns. Do this before we
6114 actually emit the sequence. */
6115 record_insns (seq, NULL, &epilogue_insn_hash);
6116 set_insn_locations (seq, epilogue_location);
6118 emit_insn_before (seq, insn);
6122 if (epilogue_seq)
6124 rtx_insn *insn, *next;
6126 /* Similarly, move any line notes that appear after the epilogue.
6127 There is no need, however, to be quite so anal about the existence
6128 of such a note. Also possibly move
6129 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6130 info generation. */
6131 for (insn = epilogue_seq; insn; insn = next)
6133 next = NEXT_INSN (insn);
6134 if (NOTE_P (insn)
6135 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6136 reorder_insns (insn, insn, PREV_INSN (epilogue_seq));
6140 /* Threading the prologue and epilogue changes the artificial refs
6141 in the entry and exit blocks. */
6142 epilogue_completed = 1;
6143 df_update_entry_exit_and_calls ();
6146 /* Reposition the prologue-end and epilogue-begin notes after
6147 instruction scheduling. */
6149 void
6150 reposition_prologue_and_epilogue_notes (void)
6152 if (!targetm.have_prologue ()
6153 && !targetm.have_epilogue ()
6154 && !targetm.have_sibcall_epilogue ())
6155 return;
6157 /* Since the hash table is created on demand, the fact that it is
6158 non-null is a signal that it is non-empty. */
6159 if (prologue_insn_hash != NULL)
6161 size_t len = prologue_insn_hash->elements ();
6162 rtx_insn *insn, *last = NULL, *note = NULL;
6164 /* Scan from the beginning until we reach the last prologue insn. */
6165 /* ??? While we do have the CFG intact, there are two problems:
6166 (1) The prologue can contain loops (typically probing the stack),
6167 which means that the end of the prologue isn't in the first bb.
6168 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6169 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6171 if (NOTE_P (insn))
6173 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6174 note = insn;
6176 else if (contains (insn, prologue_insn_hash))
6178 last = insn;
6179 if (--len == 0)
6180 break;
6184 if (last)
6186 if (note == NULL)
6188 /* Scan forward looking for the PROLOGUE_END note. It should
6189 be right at the beginning of the block, possibly with other
6190 insn notes that got moved there. */
6191 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6193 if (NOTE_P (note)
6194 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6195 break;
6199 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6200 if (LABEL_P (last))
6201 last = NEXT_INSN (last);
6202 reorder_insns (note, note, last);
6206 if (epilogue_insn_hash != NULL)
6208 edge_iterator ei;
6209 edge e;
6211 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6213 rtx_insn *insn, *first = NULL, *note = NULL;
6214 basic_block bb = e->src;
6216 /* Scan from the beginning until we reach the first epilogue insn. */
6217 FOR_BB_INSNS (bb, insn)
6219 if (NOTE_P (insn))
6221 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6223 note = insn;
6224 if (first != NULL)
6225 break;
6228 else if (first == NULL && contains (insn, epilogue_insn_hash))
6230 first = insn;
6231 if (note != NULL)
6232 break;
6236 if (note)
6238 /* If the function has a single basic block, and no real
6239 epilogue insns (e.g. sibcall with no cleanup), the
6240 epilogue note can get scheduled before the prologue
6241 note. If we have frame related prologue insns, having
6242 them scanned during the epilogue will result in a crash.
6243 In this case re-order the epilogue note to just before
6244 the last insn in the block. */
6245 if (first == NULL)
6246 first = BB_END (bb);
6248 if (PREV_INSN (first) != note)
6249 reorder_insns (note, note, PREV_INSN (first));
6255 /* Returns the name of function declared by FNDECL. */
6256 const char *
6257 fndecl_name (tree fndecl)
6259 if (fndecl == NULL)
6260 return "(nofn)";
6261 return lang_hooks.decl_printable_name (fndecl, 1);
6264 /* Returns the name of function FN. */
6265 const char *
6266 function_name (struct function *fn)
6268 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6269 return fndecl_name (fndecl);
6272 /* Returns the name of the current function. */
6273 const char *
6274 current_function_name (void)
6276 return function_name (cfun);
6280 static unsigned int
6281 rest_of_handle_check_leaf_regs (void)
6283 #ifdef LEAF_REGISTERS
6284 crtl->uses_only_leaf_regs
6285 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6286 #endif
6287 return 0;
6290 /* Insert a TYPE into the used types hash table of CFUN. */
6292 static void
6293 used_types_insert_helper (tree type, struct function *func)
6295 if (type != NULL && func != NULL)
6297 if (func->used_types_hash == NULL)
6298 func->used_types_hash = hash_set<tree>::create_ggc (37);
6300 func->used_types_hash->add (type);
6304 /* Given a type, insert it into the used hash table in cfun. */
6305 void
6306 used_types_insert (tree t)
6308 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6309 if (TYPE_NAME (t))
6310 break;
6311 else
6312 t = TREE_TYPE (t);
6313 if (TREE_CODE (t) == ERROR_MARK)
6314 return;
6315 if (TYPE_NAME (t) == NULL_TREE
6316 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6317 t = TYPE_MAIN_VARIANT (t);
6318 if (debug_info_level > DINFO_LEVEL_NONE)
6320 if (cfun)
6321 used_types_insert_helper (t, cfun);
6322 else
6324 /* So this might be a type referenced by a global variable.
6325 Record that type so that we can later decide to emit its
6326 debug information. */
6327 vec_safe_push (types_used_by_cur_var_decl, t);
6332 /* Helper to Hash a struct types_used_by_vars_entry. */
6334 static hashval_t
6335 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6337 gcc_assert (entry && entry->var_decl && entry->type);
6339 return iterative_hash_object (entry->type,
6340 iterative_hash_object (entry->var_decl, 0));
6343 /* Hash function of the types_used_by_vars_entry hash table. */
6345 hashval_t
6346 used_type_hasher::hash (types_used_by_vars_entry *entry)
6348 return hash_types_used_by_vars_entry (entry);
6351 /*Equality function of the types_used_by_vars_entry hash table. */
6353 bool
6354 used_type_hasher::equal (types_used_by_vars_entry *e1,
6355 types_used_by_vars_entry *e2)
6357 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6360 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6362 void
6363 types_used_by_var_decl_insert (tree type, tree var_decl)
6365 if (type != NULL && var_decl != NULL)
6367 types_used_by_vars_entry **slot;
6368 struct types_used_by_vars_entry e;
6369 e.var_decl = var_decl;
6370 e.type = type;
6371 if (types_used_by_vars_hash == NULL)
6372 types_used_by_vars_hash
6373 = hash_table<used_type_hasher>::create_ggc (37);
6375 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6376 if (*slot == NULL)
6378 struct types_used_by_vars_entry *entry;
6379 entry = ggc_alloc<types_used_by_vars_entry> ();
6380 entry->type = type;
6381 entry->var_decl = var_decl;
6382 *slot = entry;
6387 namespace {
6389 const pass_data pass_data_leaf_regs =
6391 RTL_PASS, /* type */
6392 "*leaf_regs", /* name */
6393 OPTGROUP_NONE, /* optinfo_flags */
6394 TV_NONE, /* tv_id */
6395 0, /* properties_required */
6396 0, /* properties_provided */
6397 0, /* properties_destroyed */
6398 0, /* todo_flags_start */
6399 0, /* todo_flags_finish */
6402 class pass_leaf_regs : public rtl_opt_pass
6404 public:
6405 pass_leaf_regs (gcc::context *ctxt)
6406 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6409 /* opt_pass methods: */
6410 virtual unsigned int execute (function *)
6412 return rest_of_handle_check_leaf_regs ();
6415 }; // class pass_leaf_regs
6417 } // anon namespace
6419 rtl_opt_pass *
6420 make_pass_leaf_regs (gcc::context *ctxt)
6422 return new pass_leaf_regs (ctxt);
6425 static unsigned int
6426 rest_of_handle_thread_prologue_and_epilogue (void)
6428 /* prepare_shrink_wrap is sensitive to the block structure of the control
6429 flow graph, so clean it up first. */
6430 if (optimize)
6431 cleanup_cfg (0);
6433 /* On some machines, the prologue and epilogue code, or parts thereof,
6434 can be represented as RTL. Doing so lets us schedule insns between
6435 it and the rest of the code and also allows delayed branch
6436 scheduling to operate in the epilogue. */
6437 thread_prologue_and_epilogue_insns ();
6439 /* Some non-cold blocks may now be only reachable from cold blocks.
6440 Fix that up. */
6441 fixup_partitions ();
6443 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6444 see PR57320. */
6445 cleanup_cfg (optimize ? CLEANUP_EXPENSIVE : 0);
6447 /* The stack usage info is finalized during prologue expansion. */
6448 if (flag_stack_usage_info)
6449 output_stack_usage ();
6451 return 0;
6454 namespace {
6456 const pass_data pass_data_thread_prologue_and_epilogue =
6458 RTL_PASS, /* type */
6459 "pro_and_epilogue", /* name */
6460 OPTGROUP_NONE, /* optinfo_flags */
6461 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6462 0, /* properties_required */
6463 0, /* properties_provided */
6464 0, /* properties_destroyed */
6465 0, /* todo_flags_start */
6466 ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
6469 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6471 public:
6472 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6473 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6476 /* opt_pass methods: */
6477 virtual unsigned int execute (function *)
6479 return rest_of_handle_thread_prologue_and_epilogue ();
6482 }; // class pass_thread_prologue_and_epilogue
6484 } // anon namespace
6486 rtl_opt_pass *
6487 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6489 return new pass_thread_prologue_and_epilogue (ctxt);
6493 /* This mini-pass fixes fall-out from SSA in asm statements that have
6494 in-out constraints. Say you start with
6496 orig = inout;
6497 asm ("": "+mr" (inout));
6498 use (orig);
6500 which is transformed very early to use explicit output and match operands:
6502 orig = inout;
6503 asm ("": "=mr" (inout) : "0" (inout));
6504 use (orig);
6506 Or, after SSA and copyprop,
6508 asm ("": "=mr" (inout_2) : "0" (inout_1));
6509 use (inout_1);
6511 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6512 they represent two separate values, so they will get different pseudo
6513 registers during expansion. Then, since the two operands need to match
6514 per the constraints, but use different pseudo registers, reload can
6515 only register a reload for these operands. But reloads can only be
6516 satisfied by hardregs, not by memory, so we need a register for this
6517 reload, just because we are presented with non-matching operands.
6518 So, even though we allow memory for this operand, no memory can be
6519 used for it, just because the two operands don't match. This can
6520 cause reload failures on register-starved targets.
6522 So it's a symptom of reload not being able to use memory for reloads
6523 or, alternatively it's also a symptom of both operands not coming into
6524 reload as matching (in which case the pseudo could go to memory just
6525 fine, as the alternative allows it, and no reload would be necessary).
6526 We fix the latter problem here, by transforming
6528 asm ("": "=mr" (inout_2) : "0" (inout_1));
6530 back to
6532 inout_2 = inout_1;
6533 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6535 static void
6536 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
6538 int i;
6539 bool changed = false;
6540 rtx op = SET_SRC (p_sets[0]);
6541 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6542 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6543 bool *output_matched = XALLOCAVEC (bool, noutputs);
6545 memset (output_matched, 0, noutputs * sizeof (bool));
6546 for (i = 0; i < ninputs; i++)
6548 rtx input, output;
6549 rtx_insn *insns;
6550 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6551 char *end;
6552 int match, j;
6554 if (*constraint == '%')
6555 constraint++;
6557 match = strtoul (constraint, &end, 10);
6558 if (end == constraint)
6559 continue;
6561 gcc_assert (match < noutputs);
6562 output = SET_DEST (p_sets[match]);
6563 input = RTVEC_ELT (inputs, i);
6564 /* Only do the transformation for pseudos. */
6565 if (! REG_P (output)
6566 || rtx_equal_p (output, input)
6567 || (GET_MODE (input) != VOIDmode
6568 && GET_MODE (input) != GET_MODE (output)))
6569 continue;
6571 /* We can't do anything if the output is also used as input,
6572 as we're going to overwrite it. */
6573 for (j = 0; j < ninputs; j++)
6574 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6575 break;
6576 if (j != ninputs)
6577 continue;
6579 /* Avoid changing the same input several times. For
6580 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6581 only change in once (to out1), rather than changing it
6582 first to out1 and afterwards to out2. */
6583 if (i > 0)
6585 for (j = 0; j < noutputs; j++)
6586 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6587 break;
6588 if (j != noutputs)
6589 continue;
6591 output_matched[match] = true;
6593 start_sequence ();
6594 emit_move_insn (output, input);
6595 insns = get_insns ();
6596 end_sequence ();
6597 emit_insn_before (insns, insn);
6599 /* Now replace all mentions of the input with output. We can't
6600 just replace the occurrence in inputs[i], as the register might
6601 also be used in some other input (or even in an address of an
6602 output), which would mean possibly increasing the number of
6603 inputs by one (namely 'output' in addition), which might pose
6604 a too complicated problem for reload to solve. E.g. this situation:
6606 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6608 Here 'input' is used in two occurrences as input (once for the
6609 input operand, once for the address in the second output operand).
6610 If we would replace only the occurrence of the input operand (to
6611 make the matching) we would be left with this:
6613 output = input
6614 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6616 Now we suddenly have two different input values (containing the same
6617 value, but different pseudos) where we formerly had only one.
6618 With more complicated asms this might lead to reload failures
6619 which wouldn't have happen without this pass. So, iterate over
6620 all operands and replace all occurrences of the register used. */
6621 for (j = 0; j < noutputs; j++)
6622 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6623 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6624 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6625 input, output);
6626 for (j = 0; j < ninputs; j++)
6627 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6628 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6629 input, output);
6631 changed = true;
6634 if (changed)
6635 df_insn_rescan (insn);
6638 /* Add the decl D to the local_decls list of FUN. */
6640 void
6641 add_local_decl (struct function *fun, tree d)
6643 gcc_assert (VAR_P (d));
6644 vec_safe_push (fun->local_decls, d);
6647 namespace {
6649 const pass_data pass_data_match_asm_constraints =
6651 RTL_PASS, /* type */
6652 "asmcons", /* name */
6653 OPTGROUP_NONE, /* optinfo_flags */
6654 TV_NONE, /* tv_id */
6655 0, /* properties_required */
6656 0, /* properties_provided */
6657 0, /* properties_destroyed */
6658 0, /* todo_flags_start */
6659 0, /* todo_flags_finish */
6662 class pass_match_asm_constraints : public rtl_opt_pass
6664 public:
6665 pass_match_asm_constraints (gcc::context *ctxt)
6666 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6669 /* opt_pass methods: */
6670 virtual unsigned int execute (function *);
6672 }; // class pass_match_asm_constraints
6674 unsigned
6675 pass_match_asm_constraints::execute (function *fun)
6677 basic_block bb;
6678 rtx_insn *insn;
6679 rtx pat, *p_sets;
6680 int noutputs;
6682 if (!crtl->has_asm_statement)
6683 return 0;
6685 df_set_flags (DF_DEFER_INSN_RESCAN);
6686 FOR_EACH_BB_FN (bb, fun)
6688 FOR_BB_INSNS (bb, insn)
6690 if (!INSN_P (insn))
6691 continue;
6693 pat = PATTERN (insn);
6694 if (GET_CODE (pat) == PARALLEL)
6695 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6696 else if (GET_CODE (pat) == SET)
6697 p_sets = &PATTERN (insn), noutputs = 1;
6698 else
6699 continue;
6701 if (GET_CODE (*p_sets) == SET
6702 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6703 match_asm_constraints_1 (insn, p_sets, noutputs);
6707 return TODO_df_finish;
6710 } // anon namespace
6712 rtl_opt_pass *
6713 make_pass_match_asm_constraints (gcc::context *ctxt)
6715 return new pass_match_asm_constraints (ctxt);
6719 #include "gt-function.h"