* config/pa/linux-atomic.c (__kernel_cmpxchg): Reorder arguments to
[official-gcc.git] / gcc / function.c
blob8134c4e7067d6c356a11340d90cb5c0fa7a75d9a
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2015 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 "tm.h"
38 #include "rtl-error.h"
39 #include "alias.h"
40 #include "symtab.h"
41 #include "tree.h"
42 #include "fold-const.h"
43 #include "stor-layout.h"
44 #include "varasm.h"
45 #include "stringpool.h"
46 #include "flags.h"
47 #include "except.h"
48 #include "hard-reg-set.h"
49 #include "function.h"
50 #include "rtl.h"
51 #include "insn-config.h"
52 #include "expmed.h"
53 #include "dojump.h"
54 #include "explow.h"
55 #include "calls.h"
56 #include "emit-rtl.h"
57 #include "stmt.h"
58 #include "expr.h"
59 #include "insn-codes.h"
60 #include "optabs.h"
61 #include "libfuncs.h"
62 #include "regs.h"
63 #include "recog.h"
64 #include "output.h"
65 #include "tm_p.h"
66 #include "langhooks.h"
67 #include "target.h"
68 #include "common/common-target.h"
69 #include "gimple-expr.h"
70 #include "gimplify.h"
71 #include "tree-pass.h"
72 #include "predict.h"
73 #include "dominance.h"
74 #include "cfg.h"
75 #include "cfgrtl.h"
76 #include "cfganal.h"
77 #include "cfgbuild.h"
78 #include "cfgcleanup.h"
79 #include "basic-block.h"
80 #include "df.h"
81 #include "params.h"
82 #include "bb-reorder.h"
83 #include "shrink-wrap.h"
84 #include "toplev.h"
85 #include "rtl-iter.h"
86 #include "tree-chkp.h"
87 #include "rtl-chkp.h"
89 /* So we can assign to cfun in this file. */
90 #undef cfun
92 #ifndef STACK_ALIGNMENT_NEEDED
93 #define STACK_ALIGNMENT_NEEDED 1
94 #endif
96 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
98 /* Round a value to the lowest integer less than it that is a multiple of
99 the required alignment. Avoid using division in case the value is
100 negative. Assume the alignment is a power of two. */
101 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
103 /* Similar, but round to the next highest integer that meets the
104 alignment. */
105 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
107 /* Nonzero once virtual register instantiation has been done.
108 assign_stack_local uses frame_pointer_rtx when this is nonzero.
109 calls.c:emit_library_call_value_1 uses it to set up
110 post-instantiation libcalls. */
111 int virtuals_instantiated;
113 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
114 static GTY(()) int funcdef_no;
116 /* These variables hold pointers to functions to create and destroy
117 target specific, per-function data structures. */
118 struct machine_function * (*init_machine_status) (void);
120 /* The currently compiled function. */
121 struct function *cfun = 0;
123 /* These hashes record the prologue and epilogue insns. */
125 struct insn_cache_hasher : ggc_cache_ptr_hash<rtx_def>
127 static hashval_t hash (rtx x) { return htab_hash_pointer (x); }
128 static bool equal (rtx a, rtx b) { return a == b; }
131 static GTY((cache))
132 hash_table<insn_cache_hasher> *prologue_insn_hash;
133 static GTY((cache))
134 hash_table<insn_cache_hasher> *epilogue_insn_hash;
137 hash_table<used_type_hasher> *types_used_by_vars_hash = NULL;
138 vec<tree, va_gc> *types_used_by_cur_var_decl;
140 /* Forward declarations. */
142 static struct temp_slot *find_temp_slot_from_address (rtx);
143 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
144 static void pad_below (struct args_size *, machine_mode, tree);
145 static void reorder_blocks_1 (rtx_insn *, tree, vec<tree> *);
146 static int all_blocks (tree, tree *);
147 static tree *get_block_vector (tree, int *);
148 extern tree debug_find_var_in_block_tree (tree, tree);
149 /* We always define `record_insns' even if it's not used so that we
150 can always export `prologue_epilogue_contains'. */
151 static void record_insns (rtx_insn *, rtx, hash_table<insn_cache_hasher> **)
152 ATTRIBUTE_UNUSED;
153 static bool contains (const_rtx, hash_table<insn_cache_hasher> *);
154 static void prepare_function_start (void);
155 static void do_clobber_return_reg (rtx, void *);
156 static void do_use_return_reg (rtx, void *);
158 /* Stack of nested functions. */
159 /* Keep track of the cfun stack. */
161 typedef struct function *function_p;
163 static vec<function_p> function_context_stack;
165 /* Save the current context for compilation of a nested function.
166 This is called from language-specific code. */
168 void
169 push_function_context (void)
171 if (cfun == 0)
172 allocate_struct_function (NULL, false);
174 function_context_stack.safe_push (cfun);
175 set_cfun (NULL);
178 /* Restore the last saved context, at the end of a nested function.
179 This function is called from language-specific code. */
181 void
182 pop_function_context (void)
184 struct function *p = function_context_stack.pop ();
185 set_cfun (p);
186 current_function_decl = p->decl;
188 /* Reset variables that have known state during rtx generation. */
189 virtuals_instantiated = 0;
190 generating_concat_p = 1;
193 /* Clear out all parts of the state in F that can safely be discarded
194 after the function has been parsed, but not compiled, to let
195 garbage collection reclaim the memory. */
197 void
198 free_after_parsing (struct function *f)
200 f->language = 0;
203 /* Clear out all parts of the state in F that can safely be discarded
204 after the function has been compiled, to let garbage collection
205 reclaim the memory. */
207 void
208 free_after_compilation (struct function *f)
210 prologue_insn_hash = NULL;
211 epilogue_insn_hash = NULL;
213 free (crtl->emit.regno_pointer_align);
215 memset (crtl, 0, sizeof (struct rtl_data));
216 f->eh = NULL;
217 f->machine = NULL;
218 f->cfg = NULL;
220 regno_reg_rtx = NULL;
223 /* Return size needed for stack frame based on slots so far allocated.
224 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
225 the caller may have to do that. */
227 HOST_WIDE_INT
228 get_frame_size (void)
230 if (FRAME_GROWS_DOWNWARD)
231 return -frame_offset;
232 else
233 return frame_offset;
236 /* Issue an error message and return TRUE if frame OFFSET overflows in
237 the signed target pointer arithmetics for function FUNC. Otherwise
238 return FALSE. */
240 bool
241 frame_offset_overflow (HOST_WIDE_INT offset, tree func)
243 unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
245 if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
246 /* Leave room for the fixed part of the frame. */
247 - 64 * UNITS_PER_WORD)
249 error_at (DECL_SOURCE_LOCATION (func),
250 "total size of local objects too large");
251 return TRUE;
254 return FALSE;
257 /* Return stack slot alignment in bits for TYPE and MODE. */
259 static unsigned int
260 get_stack_local_alignment (tree type, machine_mode mode)
262 unsigned int alignment;
264 if (mode == BLKmode)
265 alignment = BIGGEST_ALIGNMENT;
266 else
267 alignment = GET_MODE_ALIGNMENT (mode);
269 /* Allow the frond-end to (possibly) increase the alignment of this
270 stack slot. */
271 if (! type)
272 type = lang_hooks.types.type_for_mode (mode, 0);
274 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
277 /* Determine whether it is possible to fit a stack slot of size SIZE and
278 alignment ALIGNMENT into an area in the stack frame that starts at
279 frame offset START and has a length of LENGTH. If so, store the frame
280 offset to be used for the stack slot in *POFFSET and return true;
281 return false otherwise. This function will extend the frame size when
282 given a start/length pair that lies at the end of the frame. */
284 static bool
285 try_fit_stack_local (HOST_WIDE_INT start, HOST_WIDE_INT length,
286 HOST_WIDE_INT size, unsigned int alignment,
287 HOST_WIDE_INT *poffset)
289 HOST_WIDE_INT this_frame_offset;
290 int frame_off, frame_alignment, frame_phase;
292 /* Calculate how many bytes the start of local variables is off from
293 stack alignment. */
294 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
295 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
296 frame_phase = frame_off ? frame_alignment - frame_off : 0;
298 /* Round the frame offset to the specified alignment. */
300 /* We must be careful here, since FRAME_OFFSET might be negative and
301 division with a negative dividend isn't as well defined as we might
302 like. So we instead assume that ALIGNMENT is a power of two and
303 use logical operations which are unambiguous. */
304 if (FRAME_GROWS_DOWNWARD)
305 this_frame_offset
306 = (FLOOR_ROUND (start + length - size - frame_phase,
307 (unsigned HOST_WIDE_INT) alignment)
308 + frame_phase);
309 else
310 this_frame_offset
311 = (CEIL_ROUND (start - frame_phase,
312 (unsigned HOST_WIDE_INT) alignment)
313 + frame_phase);
315 /* See if it fits. If this space is at the edge of the frame,
316 consider extending the frame to make it fit. Our caller relies on
317 this when allocating a new slot. */
318 if (frame_offset == start && this_frame_offset < frame_offset)
319 frame_offset = this_frame_offset;
320 else if (this_frame_offset < start)
321 return false;
322 else if (start + length == frame_offset
323 && this_frame_offset + size > start + length)
324 frame_offset = this_frame_offset + size;
325 else if (this_frame_offset + size > start + length)
326 return false;
328 *poffset = this_frame_offset;
329 return true;
332 /* Create a new frame_space structure describing free space in the stack
333 frame beginning at START and ending at END, and chain it into the
334 function's frame_space_list. */
336 static void
337 add_frame_space (HOST_WIDE_INT start, HOST_WIDE_INT end)
339 struct frame_space *space = ggc_alloc<frame_space> ();
340 space->next = crtl->frame_space_list;
341 crtl->frame_space_list = space;
342 space->start = start;
343 space->length = end - start;
346 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
347 with machine mode MODE.
349 ALIGN controls the amount of alignment for the address of the slot:
350 0 means according to MODE,
351 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
352 -2 means use BITS_PER_UNIT,
353 positive specifies alignment boundary in bits.
355 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
356 alignment and ASLK_RECORD_PAD bit set if we should remember
357 extra space we allocated for alignment purposes. When we are
358 called from assign_stack_temp_for_type, it is not set so we don't
359 track the same stack slot in two independent lists.
361 We do not round to stack_boundary here. */
364 assign_stack_local_1 (machine_mode mode, HOST_WIDE_INT size,
365 int align, int kind)
367 rtx x, addr;
368 int bigend_correction = 0;
369 HOST_WIDE_INT slot_offset = 0, old_frame_offset;
370 unsigned int alignment, alignment_in_bits;
372 if (align == 0)
374 alignment = get_stack_local_alignment (NULL, mode);
375 alignment /= BITS_PER_UNIT;
377 else if (align == -1)
379 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
380 size = CEIL_ROUND (size, alignment);
382 else if (align == -2)
383 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
384 else
385 alignment = align / BITS_PER_UNIT;
387 alignment_in_bits = alignment * BITS_PER_UNIT;
389 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
390 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
392 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
393 alignment = alignment_in_bits / BITS_PER_UNIT;
396 if (SUPPORTS_STACK_ALIGNMENT)
398 if (crtl->stack_alignment_estimated < alignment_in_bits)
400 if (!crtl->stack_realign_processed)
401 crtl->stack_alignment_estimated = alignment_in_bits;
402 else
404 /* If stack is realigned and stack alignment value
405 hasn't been finalized, it is OK not to increase
406 stack_alignment_estimated. The bigger alignment
407 requirement is recorded in stack_alignment_needed
408 below. */
409 gcc_assert (!crtl->stack_realign_finalized);
410 if (!crtl->stack_realign_needed)
412 /* It is OK to reduce the alignment as long as the
413 requested size is 0 or the estimated stack
414 alignment >= mode alignment. */
415 gcc_assert ((kind & ASLK_REDUCE_ALIGN)
416 || size == 0
417 || (crtl->stack_alignment_estimated
418 >= GET_MODE_ALIGNMENT (mode)));
419 alignment_in_bits = crtl->stack_alignment_estimated;
420 alignment = alignment_in_bits / BITS_PER_UNIT;
426 if (crtl->stack_alignment_needed < alignment_in_bits)
427 crtl->stack_alignment_needed = alignment_in_bits;
428 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
429 crtl->max_used_stack_slot_alignment = alignment_in_bits;
431 if (mode != BLKmode || size != 0)
433 if (kind & ASLK_RECORD_PAD)
435 struct frame_space **psp;
437 for (psp = &crtl->frame_space_list; *psp; psp = &(*psp)->next)
439 struct frame_space *space = *psp;
440 if (!try_fit_stack_local (space->start, space->length, size,
441 alignment, &slot_offset))
442 continue;
443 *psp = space->next;
444 if (slot_offset > space->start)
445 add_frame_space (space->start, slot_offset);
446 if (slot_offset + size < space->start + space->length)
447 add_frame_space (slot_offset + size,
448 space->start + space->length);
449 goto found_space;
453 else if (!STACK_ALIGNMENT_NEEDED)
455 slot_offset = frame_offset;
456 goto found_space;
459 old_frame_offset = frame_offset;
461 if (FRAME_GROWS_DOWNWARD)
463 frame_offset -= size;
464 try_fit_stack_local (frame_offset, size, size, alignment, &slot_offset);
466 if (kind & ASLK_RECORD_PAD)
468 if (slot_offset > frame_offset)
469 add_frame_space (frame_offset, slot_offset);
470 if (slot_offset + size < old_frame_offset)
471 add_frame_space (slot_offset + size, old_frame_offset);
474 else
476 frame_offset += size;
477 try_fit_stack_local (old_frame_offset, size, size, alignment, &slot_offset);
479 if (kind & ASLK_RECORD_PAD)
481 if (slot_offset > old_frame_offset)
482 add_frame_space (old_frame_offset, slot_offset);
483 if (slot_offset + size < frame_offset)
484 add_frame_space (slot_offset + size, frame_offset);
488 found_space:
489 /* On a big-endian machine, if we are allocating more space than we will use,
490 use the least significant bytes of those that are allocated. */
491 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
492 bigend_correction = size - GET_MODE_SIZE (mode);
494 /* If we have already instantiated virtual registers, return the actual
495 address relative to the frame pointer. */
496 if (virtuals_instantiated)
497 addr = plus_constant (Pmode, frame_pointer_rtx,
498 trunc_int_for_mode
499 (slot_offset + bigend_correction
500 + STARTING_FRAME_OFFSET, Pmode));
501 else
502 addr = plus_constant (Pmode, virtual_stack_vars_rtx,
503 trunc_int_for_mode
504 (slot_offset + bigend_correction,
505 Pmode));
507 x = gen_rtx_MEM (mode, addr);
508 set_mem_align (x, alignment_in_bits);
509 MEM_NOTRAP_P (x) = 1;
511 stack_slot_list
512 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
514 if (frame_offset_overflow (frame_offset, current_function_decl))
515 frame_offset = 0;
517 return x;
520 /* Wrap up assign_stack_local_1 with last parameter as false. */
523 assign_stack_local (machine_mode mode, HOST_WIDE_INT size, int align)
525 return assign_stack_local_1 (mode, size, align, ASLK_RECORD_PAD);
528 /* In order to evaluate some expressions, such as function calls returning
529 structures in memory, we need to temporarily allocate stack locations.
530 We record each allocated temporary in the following structure.
532 Associated with each temporary slot is a nesting level. When we pop up
533 one level, all temporaries associated with the previous level are freed.
534 Normally, all temporaries are freed after the execution of the statement
535 in which they were created. However, if we are inside a ({...}) grouping,
536 the result may be in a temporary and hence must be preserved. If the
537 result could be in a temporary, we preserve it if we can determine which
538 one it is in. If we cannot determine which temporary may contain the
539 result, all temporaries are preserved. A temporary is preserved by
540 pretending it was allocated at the previous nesting level. */
542 struct GTY(()) temp_slot {
543 /* Points to next temporary slot. */
544 struct temp_slot *next;
545 /* Points to previous temporary slot. */
546 struct temp_slot *prev;
547 /* The rtx to used to reference the slot. */
548 rtx slot;
549 /* The size, in units, of the slot. */
550 HOST_WIDE_INT size;
551 /* The type of the object in the slot, or zero if it doesn't correspond
552 to a type. We use this to determine whether a slot can be reused.
553 It can be reused if objects of the type of the new slot will always
554 conflict with objects of the type of the old slot. */
555 tree type;
556 /* The alignment (in bits) of the slot. */
557 unsigned int align;
558 /* Nonzero if this temporary is currently in use. */
559 char in_use;
560 /* Nesting level at which this slot is being used. */
561 int level;
562 /* The offset of the slot from the frame_pointer, including extra space
563 for alignment. This info is for combine_temp_slots. */
564 HOST_WIDE_INT base_offset;
565 /* The size of the slot, including extra space for alignment. This
566 info is for combine_temp_slots. */
567 HOST_WIDE_INT full_size;
570 /* Entry for the below hash table. */
571 struct GTY((for_user)) temp_slot_address_entry {
572 hashval_t hash;
573 rtx address;
574 struct temp_slot *temp_slot;
577 struct temp_address_hasher : ggc_ptr_hash<temp_slot_address_entry>
579 static hashval_t hash (temp_slot_address_entry *);
580 static bool equal (temp_slot_address_entry *, temp_slot_address_entry *);
583 /* A table of addresses that represent a stack slot. The table is a mapping
584 from address RTXen to a temp slot. */
585 static GTY(()) hash_table<temp_address_hasher> *temp_slot_address_table;
586 static size_t n_temp_slots_in_use;
588 /* Removes temporary slot TEMP from LIST. */
590 static void
591 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
593 if (temp->next)
594 temp->next->prev = temp->prev;
595 if (temp->prev)
596 temp->prev->next = temp->next;
597 else
598 *list = temp->next;
600 temp->prev = temp->next = NULL;
603 /* Inserts temporary slot TEMP to LIST. */
605 static void
606 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
608 temp->next = *list;
609 if (*list)
610 (*list)->prev = temp;
611 temp->prev = NULL;
612 *list = temp;
615 /* Returns the list of used temp slots at LEVEL. */
617 static struct temp_slot **
618 temp_slots_at_level (int level)
620 if (level >= (int) vec_safe_length (used_temp_slots))
621 vec_safe_grow_cleared (used_temp_slots, level + 1);
623 return &(*used_temp_slots)[level];
626 /* Returns the maximal temporary slot level. */
628 static int
629 max_slot_level (void)
631 if (!used_temp_slots)
632 return -1;
634 return used_temp_slots->length () - 1;
637 /* Moves temporary slot TEMP to LEVEL. */
639 static void
640 move_slot_to_level (struct temp_slot *temp, int level)
642 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
643 insert_slot_to_list (temp, temp_slots_at_level (level));
644 temp->level = level;
647 /* Make temporary slot TEMP available. */
649 static void
650 make_slot_available (struct temp_slot *temp)
652 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
653 insert_slot_to_list (temp, &avail_temp_slots);
654 temp->in_use = 0;
655 temp->level = -1;
656 n_temp_slots_in_use--;
659 /* Compute the hash value for an address -> temp slot mapping.
660 The value is cached on the mapping entry. */
661 static hashval_t
662 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
664 int do_not_record = 0;
665 return hash_rtx (t->address, GET_MODE (t->address),
666 &do_not_record, NULL, false);
669 /* Return the hash value for an address -> temp slot mapping. */
670 hashval_t
671 temp_address_hasher::hash (temp_slot_address_entry *t)
673 return t->hash;
676 /* Compare two address -> temp slot mapping entries. */
677 bool
678 temp_address_hasher::equal (temp_slot_address_entry *t1,
679 temp_slot_address_entry *t2)
681 return exp_equiv_p (t1->address, t2->address, 0, true);
684 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
685 static void
686 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
688 struct temp_slot_address_entry *t = ggc_alloc<temp_slot_address_entry> ();
689 t->address = address;
690 t->temp_slot = temp_slot;
691 t->hash = temp_slot_address_compute_hash (t);
692 *temp_slot_address_table->find_slot_with_hash (t, t->hash, INSERT) = t;
695 /* Remove an address -> temp slot mapping entry if the temp slot is
696 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
698 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry **slot, void *)
700 const struct temp_slot_address_entry *t = *slot;
701 if (! t->temp_slot->in_use)
702 temp_slot_address_table->clear_slot (slot);
703 return 1;
706 /* Remove all mappings of addresses to unused temp slots. */
707 static void
708 remove_unused_temp_slot_addresses (void)
710 /* Use quicker clearing if there aren't any active temp slots. */
711 if (n_temp_slots_in_use)
712 temp_slot_address_table->traverse
713 <void *, remove_unused_temp_slot_addresses_1> (NULL);
714 else
715 temp_slot_address_table->empty ();
718 /* Find the temp slot corresponding to the object at address X. */
720 static struct temp_slot *
721 find_temp_slot_from_address (rtx x)
723 struct temp_slot *p;
724 struct temp_slot_address_entry tmp, *t;
726 /* First try the easy way:
727 See if X exists in the address -> temp slot mapping. */
728 tmp.address = x;
729 tmp.temp_slot = NULL;
730 tmp.hash = temp_slot_address_compute_hash (&tmp);
731 t = temp_slot_address_table->find_with_hash (&tmp, tmp.hash);
732 if (t)
733 return t->temp_slot;
735 /* If we have a sum involving a register, see if it points to a temp
736 slot. */
737 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
738 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
739 return p;
740 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
741 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
742 return p;
744 /* Last resort: Address is a virtual stack var address. */
745 if (GET_CODE (x) == PLUS
746 && XEXP (x, 0) == virtual_stack_vars_rtx
747 && CONST_INT_P (XEXP (x, 1)))
749 int i;
750 for (i = max_slot_level (); i >= 0; i--)
751 for (p = *temp_slots_at_level (i); p; p = p->next)
753 if (INTVAL (XEXP (x, 1)) >= p->base_offset
754 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
755 return p;
759 return NULL;
762 /* Allocate a temporary stack slot and record it for possible later
763 reuse.
765 MODE is the machine mode to be given to the returned rtx.
767 SIZE is the size in units of the space required. We do no rounding here
768 since assign_stack_local will do any required rounding.
770 TYPE is the type that will be used for the stack slot. */
773 assign_stack_temp_for_type (machine_mode mode, HOST_WIDE_INT size,
774 tree type)
776 unsigned int align;
777 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
778 rtx slot;
780 /* If SIZE is -1 it means that somebody tried to allocate a temporary
781 of a variable size. */
782 gcc_assert (size != -1);
784 align = get_stack_local_alignment (type, mode);
786 /* Try to find an available, already-allocated temporary of the proper
787 mode which meets the size and alignment requirements. Choose the
788 smallest one with the closest alignment.
790 If assign_stack_temp is called outside of the tree->rtl expansion,
791 we cannot reuse the stack slots (that may still refer to
792 VIRTUAL_STACK_VARS_REGNUM). */
793 if (!virtuals_instantiated)
795 for (p = avail_temp_slots; p; p = p->next)
797 if (p->align >= align && p->size >= size
798 && GET_MODE (p->slot) == mode
799 && objects_must_conflict_p (p->type, type)
800 && (best_p == 0 || best_p->size > p->size
801 || (best_p->size == p->size && best_p->align > p->align)))
803 if (p->align == align && p->size == size)
805 selected = p;
806 cut_slot_from_list (selected, &avail_temp_slots);
807 best_p = 0;
808 break;
810 best_p = p;
815 /* Make our best, if any, the one to use. */
816 if (best_p)
818 selected = best_p;
819 cut_slot_from_list (selected, &avail_temp_slots);
821 /* If there are enough aligned bytes left over, make them into a new
822 temp_slot so that the extra bytes don't get wasted. Do this only
823 for BLKmode slots, so that we can be sure of the alignment. */
824 if (GET_MODE (best_p->slot) == BLKmode)
826 int alignment = best_p->align / BITS_PER_UNIT;
827 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
829 if (best_p->size - rounded_size >= alignment)
831 p = ggc_alloc<temp_slot> ();
832 p->in_use = 0;
833 p->size = best_p->size - rounded_size;
834 p->base_offset = best_p->base_offset + rounded_size;
835 p->full_size = best_p->full_size - rounded_size;
836 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
837 p->align = best_p->align;
838 p->type = best_p->type;
839 insert_slot_to_list (p, &avail_temp_slots);
841 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
842 stack_slot_list);
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 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
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 if (mode == BLKmode || memory_required)
970 HOST_WIDE_INT size = int_size_in_bytes (type);
971 rtx tmp;
973 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
974 problems with allocating the stack space. */
975 if (size == 0)
976 size = 1;
978 /* Unfortunately, we don't yet know how to allocate variable-sized
979 temporaries. However, sometimes we can find a fixed upper limit on
980 the size, so try that instead. */
981 else if (size == -1)
982 size = max_int_size_in_bytes (type);
984 /* The size of the temporary may be too large to fit into an integer. */
985 /* ??? Not sure this should happen except for user silliness, so limit
986 this to things that aren't compiler-generated temporaries. The
987 rest of the time we'll die in assign_stack_temp_for_type. */
988 if (decl && size == -1
989 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
991 error ("size of variable %q+D is too large", decl);
992 size = 1;
995 tmp = assign_stack_temp_for_type (mode, size, type);
996 return tmp;
999 #ifdef PROMOTE_MODE
1000 if (! dont_promote)
1001 mode = promote_mode (type, mode, &unsignedp);
1002 #endif
1004 return gen_reg_rtx (mode);
1007 /* Combine temporary stack slots which are adjacent on the stack.
1009 This allows for better use of already allocated stack space. This is only
1010 done for BLKmode slots because we can be sure that we won't have alignment
1011 problems in this case. */
1013 static void
1014 combine_temp_slots (void)
1016 struct temp_slot *p, *q, *next, *next_q;
1017 int num_slots;
1019 /* We can't combine slots, because the information about which slot
1020 is in which alias set will be lost. */
1021 if (flag_strict_aliasing)
1022 return;
1024 /* If there are a lot of temp slots, don't do anything unless
1025 high levels of optimization. */
1026 if (! flag_expensive_optimizations)
1027 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
1028 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
1029 return;
1031 for (p = avail_temp_slots; p; p = next)
1033 int delete_p = 0;
1035 next = p->next;
1037 if (GET_MODE (p->slot) != BLKmode)
1038 continue;
1040 for (q = p->next; q; q = next_q)
1042 int delete_q = 0;
1044 next_q = q->next;
1046 if (GET_MODE (q->slot) != BLKmode)
1047 continue;
1049 if (p->base_offset + p->full_size == q->base_offset)
1051 /* Q comes after P; combine Q into P. */
1052 p->size += q->size;
1053 p->full_size += q->full_size;
1054 delete_q = 1;
1056 else if (q->base_offset + q->full_size == p->base_offset)
1058 /* P comes after Q; combine P into Q. */
1059 q->size += p->size;
1060 q->full_size += p->full_size;
1061 delete_p = 1;
1062 break;
1064 if (delete_q)
1065 cut_slot_from_list (q, &avail_temp_slots);
1068 /* Either delete P or advance past it. */
1069 if (delete_p)
1070 cut_slot_from_list (p, &avail_temp_slots);
1074 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1075 slot that previously was known by OLD_RTX. */
1077 void
1078 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1080 struct temp_slot *p;
1082 if (rtx_equal_p (old_rtx, new_rtx))
1083 return;
1085 p = find_temp_slot_from_address (old_rtx);
1087 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1088 NEW_RTX is a register, see if one operand of the PLUS is a
1089 temporary location. If so, NEW_RTX points into it. Otherwise,
1090 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1091 in common between them. If so, try a recursive call on those
1092 values. */
1093 if (p == 0)
1095 if (GET_CODE (old_rtx) != PLUS)
1096 return;
1098 if (REG_P (new_rtx))
1100 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1101 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1102 return;
1104 else if (GET_CODE (new_rtx) != PLUS)
1105 return;
1107 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1108 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1109 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1110 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1111 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1112 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1113 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1114 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1116 return;
1119 /* Otherwise add an alias for the temp's address. */
1120 insert_temp_slot_address (new_rtx, p);
1123 /* If X could be a reference to a temporary slot, mark that slot as
1124 belonging to the to one level higher than the current level. If X
1125 matched one of our slots, just mark that one. Otherwise, we can't
1126 easily predict which it is, so upgrade all of them.
1128 This is called when an ({...}) construct occurs and a statement
1129 returns a value in memory. */
1131 void
1132 preserve_temp_slots (rtx x)
1134 struct temp_slot *p = 0, *next;
1136 if (x == 0)
1137 return;
1139 /* If X is a register that is being used as a pointer, see if we have
1140 a temporary slot we know it points to. */
1141 if (REG_P (x) && REG_POINTER (x))
1142 p = find_temp_slot_from_address (x);
1144 /* If X is not in memory or is at a constant address, it cannot be in
1145 a temporary slot. */
1146 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1147 return;
1149 /* First see if we can find a match. */
1150 if (p == 0)
1151 p = find_temp_slot_from_address (XEXP (x, 0));
1153 if (p != 0)
1155 if (p->level == temp_slot_level)
1156 move_slot_to_level (p, temp_slot_level - 1);
1157 return;
1160 /* Otherwise, preserve all non-kept slots at this level. */
1161 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1163 next = p->next;
1164 move_slot_to_level (p, temp_slot_level - 1);
1168 /* Free all temporaries used so far. This is normally called at the
1169 end of generating code for a statement. */
1171 void
1172 free_temp_slots (void)
1174 struct temp_slot *p, *next;
1175 bool some_available = false;
1177 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1179 next = p->next;
1180 make_slot_available (p);
1181 some_available = true;
1184 if (some_available)
1186 remove_unused_temp_slot_addresses ();
1187 combine_temp_slots ();
1191 /* Push deeper into the nesting level for stack temporaries. */
1193 void
1194 push_temp_slots (void)
1196 temp_slot_level++;
1199 /* Pop a temporary nesting level. All slots in use in the current level
1200 are freed. */
1202 void
1203 pop_temp_slots (void)
1205 free_temp_slots ();
1206 temp_slot_level--;
1209 /* Initialize temporary slots. */
1211 void
1212 init_temp_slots (void)
1214 /* We have not allocated any temporaries yet. */
1215 avail_temp_slots = 0;
1216 vec_alloc (used_temp_slots, 0);
1217 temp_slot_level = 0;
1218 n_temp_slots_in_use = 0;
1220 /* Set up the table to map addresses to temp slots. */
1221 if (! temp_slot_address_table)
1222 temp_slot_address_table = hash_table<temp_address_hasher>::create_ggc (32);
1223 else
1224 temp_slot_address_table->empty ();
1227 /* Functions and data structures to keep track of the values hard regs
1228 had at the start of the function. */
1230 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1231 and has_hard_reg_initial_val.. */
1232 typedef struct GTY(()) initial_value_pair {
1233 rtx hard_reg;
1234 rtx pseudo;
1235 } initial_value_pair;
1236 /* ??? This could be a VEC but there is currently no way to define an
1237 opaque VEC type. This could be worked around by defining struct
1238 initial_value_pair in function.h. */
1239 typedef struct GTY(()) initial_value_struct {
1240 int num_entries;
1241 int max_entries;
1242 initial_value_pair * GTY ((length ("%h.num_entries"))) entries;
1243 } initial_value_struct;
1245 /* If a pseudo represents an initial hard reg (or expression), return
1246 it, else return NULL_RTX. */
1249 get_hard_reg_initial_reg (rtx reg)
1251 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1252 int i;
1254 if (ivs == 0)
1255 return NULL_RTX;
1257 for (i = 0; i < ivs->num_entries; i++)
1258 if (rtx_equal_p (ivs->entries[i].pseudo, reg))
1259 return ivs->entries[i].hard_reg;
1261 return NULL_RTX;
1264 /* Make sure that there's a pseudo register of mode MODE that stores the
1265 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1268 get_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1270 struct initial_value_struct *ivs;
1271 rtx rv;
1273 rv = has_hard_reg_initial_val (mode, regno);
1274 if (rv)
1275 return rv;
1277 ivs = crtl->hard_reg_initial_vals;
1278 if (ivs == 0)
1280 ivs = ggc_alloc<initial_value_struct> ();
1281 ivs->num_entries = 0;
1282 ivs->max_entries = 5;
1283 ivs->entries = ggc_vec_alloc<initial_value_pair> (5);
1284 crtl->hard_reg_initial_vals = ivs;
1287 if (ivs->num_entries >= ivs->max_entries)
1289 ivs->max_entries += 5;
1290 ivs->entries = GGC_RESIZEVEC (initial_value_pair, ivs->entries,
1291 ivs->max_entries);
1294 ivs->entries[ivs->num_entries].hard_reg = gen_rtx_REG (mode, regno);
1295 ivs->entries[ivs->num_entries].pseudo = gen_reg_rtx (mode);
1297 return ivs->entries[ivs->num_entries++].pseudo;
1300 /* See if get_hard_reg_initial_val has been used to create a pseudo
1301 for the initial value of hard register REGNO in mode MODE. Return
1302 the associated pseudo if so, otherwise return NULL. */
1305 has_hard_reg_initial_val (machine_mode mode, unsigned int regno)
1307 struct initial_value_struct *ivs;
1308 int i;
1310 ivs = crtl->hard_reg_initial_vals;
1311 if (ivs != 0)
1312 for (i = 0; i < ivs->num_entries; i++)
1313 if (GET_MODE (ivs->entries[i].hard_reg) == mode
1314 && REGNO (ivs->entries[i].hard_reg) == regno)
1315 return ivs->entries[i].pseudo;
1317 return NULL_RTX;
1320 unsigned int
1321 emit_initial_value_sets (void)
1323 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1324 int i;
1325 rtx_insn *seq;
1327 if (ivs == 0)
1328 return 0;
1330 start_sequence ();
1331 for (i = 0; i < ivs->num_entries; i++)
1332 emit_move_insn (ivs->entries[i].pseudo, ivs->entries[i].hard_reg);
1333 seq = get_insns ();
1334 end_sequence ();
1336 emit_insn_at_entry (seq);
1337 return 0;
1340 /* Return the hardreg-pseudoreg initial values pair entry I and
1341 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1342 bool
1343 initial_value_entry (int i, rtx *hreg, rtx *preg)
1345 struct initial_value_struct *ivs = crtl->hard_reg_initial_vals;
1346 if (!ivs || i >= ivs->num_entries)
1347 return false;
1349 *hreg = ivs->entries[i].hard_reg;
1350 *preg = ivs->entries[i].pseudo;
1351 return true;
1354 /* These routines are responsible for converting virtual register references
1355 to the actual hard register references once RTL generation is complete.
1357 The following four variables are used for communication between the
1358 routines. They contain the offsets of the virtual registers from their
1359 respective hard registers. */
1361 static int in_arg_offset;
1362 static int var_offset;
1363 static int dynamic_offset;
1364 static int out_arg_offset;
1365 static int cfa_offset;
1367 /* In most machines, the stack pointer register is equivalent to the bottom
1368 of the stack. */
1370 #ifndef STACK_POINTER_OFFSET
1371 #define STACK_POINTER_OFFSET 0
1372 #endif
1374 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1375 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1376 #endif
1378 /* If not defined, pick an appropriate default for the offset of dynamically
1379 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1380 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1382 #ifndef STACK_DYNAMIC_OFFSET
1384 /* The bottom of the stack points to the actual arguments. If
1385 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1386 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1387 stack space for register parameters is not pushed by the caller, but
1388 rather part of the fixed stack areas and hence not included in
1389 `crtl->outgoing_args_size'. Nevertheless, we must allow
1390 for it when allocating stack dynamic objects. */
1392 #ifdef INCOMING_REG_PARM_STACK_SPACE
1393 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1394 ((ACCUMULATE_OUTGOING_ARGS \
1395 ? (crtl->outgoing_args_size \
1396 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1397 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1398 : 0) + (STACK_POINTER_OFFSET))
1399 #else
1400 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1401 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1402 + (STACK_POINTER_OFFSET))
1403 #endif
1404 #endif
1407 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1408 is a virtual register, return the equivalent hard register and set the
1409 offset indirectly through the pointer. Otherwise, return 0. */
1411 static rtx
1412 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1414 rtx new_rtx;
1415 HOST_WIDE_INT offset;
1417 if (x == virtual_incoming_args_rtx)
1419 if (stack_realign_drap)
1421 /* Replace virtual_incoming_args_rtx with internal arg
1422 pointer if DRAP is used to realign stack. */
1423 new_rtx = crtl->args.internal_arg_pointer;
1424 offset = 0;
1426 else
1427 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1429 else if (x == virtual_stack_vars_rtx)
1430 new_rtx = frame_pointer_rtx, offset = var_offset;
1431 else if (x == virtual_stack_dynamic_rtx)
1432 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1433 else if (x == virtual_outgoing_args_rtx)
1434 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1435 else if (x == virtual_cfa_rtx)
1437 #ifdef FRAME_POINTER_CFA_OFFSET
1438 new_rtx = frame_pointer_rtx;
1439 #else
1440 new_rtx = arg_pointer_rtx;
1441 #endif
1442 offset = cfa_offset;
1444 else if (x == virtual_preferred_stack_boundary_rtx)
1446 new_rtx = GEN_INT (crtl->preferred_stack_boundary / BITS_PER_UNIT);
1447 offset = 0;
1449 else
1450 return NULL_RTX;
1452 *poffset = offset;
1453 return new_rtx;
1456 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1457 registers present inside of *LOC. The expression is simplified,
1458 as much as possible, but is not to be considered "valid" in any sense
1459 implied by the target. Return true if any change is made. */
1461 static bool
1462 instantiate_virtual_regs_in_rtx (rtx *loc)
1464 if (!*loc)
1465 return false;
1466 bool changed = false;
1467 subrtx_ptr_iterator::array_type array;
1468 FOR_EACH_SUBRTX_PTR (iter, array, loc, NONCONST)
1470 rtx *loc = *iter;
1471 if (rtx x = *loc)
1473 rtx new_rtx;
1474 HOST_WIDE_INT offset;
1475 switch (GET_CODE (x))
1477 case REG:
1478 new_rtx = instantiate_new_reg (x, &offset);
1479 if (new_rtx)
1481 *loc = plus_constant (GET_MODE (x), new_rtx, offset);
1482 changed = true;
1484 iter.skip_subrtxes ();
1485 break;
1487 case PLUS:
1488 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1489 if (new_rtx)
1491 XEXP (x, 0) = new_rtx;
1492 *loc = plus_constant (GET_MODE (x), x, offset, true);
1493 changed = true;
1494 iter.skip_subrtxes ();
1495 break;
1498 /* FIXME -- from old code */
1499 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1500 we can commute the PLUS and SUBREG because pointers into the
1501 frame are well-behaved. */
1502 break;
1504 default:
1505 break;
1509 return changed;
1512 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1513 matches the predicate for insn CODE operand OPERAND. */
1515 static int
1516 safe_insn_predicate (int code, int operand, rtx x)
1518 return code < 0 || insn_operand_matches ((enum insn_code) code, operand, x);
1521 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1522 registers present inside of insn. The result will be a valid insn. */
1524 static void
1525 instantiate_virtual_regs_in_insn (rtx_insn *insn)
1527 HOST_WIDE_INT offset;
1528 int insn_code, i;
1529 bool any_change = false;
1530 rtx set, new_rtx, x;
1531 rtx_insn *seq;
1533 /* There are some special cases to be handled first. */
1534 set = single_set (insn);
1535 if (set)
1537 /* We're allowed to assign to a virtual register. This is interpreted
1538 to mean that the underlying register gets assigned the inverse
1539 transformation. This is used, for example, in the handling of
1540 non-local gotos. */
1541 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1542 if (new_rtx)
1544 start_sequence ();
1546 instantiate_virtual_regs_in_rtx (&SET_SRC (set));
1547 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1548 gen_int_mode (-offset, GET_MODE (new_rtx)));
1549 x = force_operand (x, new_rtx);
1550 if (x != new_rtx)
1551 emit_move_insn (new_rtx, x);
1553 seq = get_insns ();
1554 end_sequence ();
1556 emit_insn_before (seq, insn);
1557 delete_insn (insn);
1558 return;
1561 /* Handle a straight copy from a virtual register by generating a
1562 new add insn. The difference between this and falling through
1563 to the generic case is avoiding a new pseudo and eliminating a
1564 move insn in the initial rtl stream. */
1565 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1566 if (new_rtx && offset != 0
1567 && REG_P (SET_DEST (set))
1568 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1570 start_sequence ();
1572 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS, new_rtx,
1573 gen_int_mode (offset,
1574 GET_MODE (SET_DEST (set))),
1575 SET_DEST (set), 1, OPTAB_LIB_WIDEN);
1576 if (x != SET_DEST (set))
1577 emit_move_insn (SET_DEST (set), x);
1579 seq = get_insns ();
1580 end_sequence ();
1582 emit_insn_before (seq, insn);
1583 delete_insn (insn);
1584 return;
1587 extract_insn (insn);
1588 insn_code = INSN_CODE (insn);
1590 /* Handle a plus involving a virtual register by determining if the
1591 operands remain valid if they're modified in place. */
1592 if (GET_CODE (SET_SRC (set)) == PLUS
1593 && recog_data.n_operands >= 3
1594 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1595 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1596 && CONST_INT_P (recog_data.operand[2])
1597 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1599 offset += INTVAL (recog_data.operand[2]);
1601 /* If the sum is zero, then replace with a plain move. */
1602 if (offset == 0
1603 && REG_P (SET_DEST (set))
1604 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1606 start_sequence ();
1607 emit_move_insn (SET_DEST (set), new_rtx);
1608 seq = get_insns ();
1609 end_sequence ();
1611 emit_insn_before (seq, insn);
1612 delete_insn (insn);
1613 return;
1616 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1618 /* Using validate_change and apply_change_group here leaves
1619 recog_data in an invalid state. Since we know exactly what
1620 we want to check, do those two by hand. */
1621 if (safe_insn_predicate (insn_code, 1, new_rtx)
1622 && safe_insn_predicate (insn_code, 2, x))
1624 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1625 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1626 any_change = true;
1628 /* Fall through into the regular operand fixup loop in
1629 order to take care of operands other than 1 and 2. */
1633 else
1635 extract_insn (insn);
1636 insn_code = INSN_CODE (insn);
1639 /* In the general case, we expect virtual registers to appear only in
1640 operands, and then only as either bare registers or inside memories. */
1641 for (i = 0; i < recog_data.n_operands; ++i)
1643 x = recog_data.operand[i];
1644 switch (GET_CODE (x))
1646 case MEM:
1648 rtx addr = XEXP (x, 0);
1650 if (!instantiate_virtual_regs_in_rtx (&addr))
1651 continue;
1653 start_sequence ();
1654 x = replace_equiv_address (x, addr, true);
1655 /* It may happen that the address with the virtual reg
1656 was valid (e.g. based on the virtual stack reg, which might
1657 be acceptable to the predicates with all offsets), whereas
1658 the address now isn't anymore, for instance when the address
1659 is still offsetted, but the base reg isn't virtual-stack-reg
1660 anymore. Below we would do a force_reg on the whole operand,
1661 but this insn might actually only accept memory. Hence,
1662 before doing that last resort, try to reload the address into
1663 a register, so this operand stays a MEM. */
1664 if (!safe_insn_predicate (insn_code, i, x))
1666 addr = force_reg (GET_MODE (addr), addr);
1667 x = replace_equiv_address (x, addr, true);
1669 seq = get_insns ();
1670 end_sequence ();
1671 if (seq)
1672 emit_insn_before (seq, insn);
1674 break;
1676 case REG:
1677 new_rtx = instantiate_new_reg (x, &offset);
1678 if (new_rtx == NULL)
1679 continue;
1680 if (offset == 0)
1681 x = new_rtx;
1682 else
1684 start_sequence ();
1686 /* Careful, special mode predicates may have stuff in
1687 insn_data[insn_code].operand[i].mode that isn't useful
1688 to us for computing a new value. */
1689 /* ??? Recognize address_operand and/or "p" constraints
1690 to see if (plus new offset) is a valid before we put
1691 this through expand_simple_binop. */
1692 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1693 gen_int_mode (offset, GET_MODE (x)),
1694 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1695 seq = get_insns ();
1696 end_sequence ();
1697 emit_insn_before (seq, insn);
1699 break;
1701 case SUBREG:
1702 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1703 if (new_rtx == NULL)
1704 continue;
1705 if (offset != 0)
1707 start_sequence ();
1708 new_rtx = expand_simple_binop
1709 (GET_MODE (new_rtx), PLUS, new_rtx,
1710 gen_int_mode (offset, GET_MODE (new_rtx)),
1711 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1712 seq = get_insns ();
1713 end_sequence ();
1714 emit_insn_before (seq, insn);
1716 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1717 GET_MODE (new_rtx), SUBREG_BYTE (x));
1718 gcc_assert (x);
1719 break;
1721 default:
1722 continue;
1725 /* At this point, X contains the new value for the operand.
1726 Validate the new value vs the insn predicate. Note that
1727 asm insns will have insn_code -1 here. */
1728 if (!safe_insn_predicate (insn_code, i, x))
1730 start_sequence ();
1731 if (REG_P (x))
1733 gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1734 x = copy_to_reg (x);
1736 else
1737 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1738 seq = get_insns ();
1739 end_sequence ();
1740 if (seq)
1741 emit_insn_before (seq, insn);
1744 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1745 any_change = true;
1748 if (any_change)
1750 /* Propagate operand changes into the duplicates. */
1751 for (i = 0; i < recog_data.n_dups; ++i)
1752 *recog_data.dup_loc[i]
1753 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1755 /* Force re-recognition of the instruction for validation. */
1756 INSN_CODE (insn) = -1;
1759 if (asm_noperands (PATTERN (insn)) >= 0)
1761 if (!check_asm_operands (PATTERN (insn)))
1763 error_for_asm (insn, "impossible constraint in %<asm%>");
1764 /* For asm goto, instead of fixing up all the edges
1765 just clear the template and clear input operands
1766 (asm goto doesn't have any output operands). */
1767 if (JUMP_P (insn))
1769 rtx asm_op = extract_asm_operands (PATTERN (insn));
1770 ASM_OPERANDS_TEMPLATE (asm_op) = ggc_strdup ("");
1771 ASM_OPERANDS_INPUT_VEC (asm_op) = rtvec_alloc (0);
1772 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op) = rtvec_alloc (0);
1774 else
1775 delete_insn (insn);
1778 else
1780 if (recog_memoized (insn) < 0)
1781 fatal_insn_not_found (insn);
1785 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1786 do any instantiation required. */
1788 void
1789 instantiate_decl_rtl (rtx x)
1791 rtx addr;
1793 if (x == 0)
1794 return;
1796 /* If this is a CONCAT, recurse for the pieces. */
1797 if (GET_CODE (x) == CONCAT)
1799 instantiate_decl_rtl (XEXP (x, 0));
1800 instantiate_decl_rtl (XEXP (x, 1));
1801 return;
1804 /* If this is not a MEM, no need to do anything. Similarly if the
1805 address is a constant or a register that is not a virtual register. */
1806 if (!MEM_P (x))
1807 return;
1809 addr = XEXP (x, 0);
1810 if (CONSTANT_P (addr)
1811 || (REG_P (addr)
1812 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1813 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1814 return;
1816 instantiate_virtual_regs_in_rtx (&XEXP (x, 0));
1819 /* Helper for instantiate_decls called via walk_tree: Process all decls
1820 in the given DECL_VALUE_EXPR. */
1822 static tree
1823 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1825 tree t = *tp;
1826 if (! EXPR_P (t))
1828 *walk_subtrees = 0;
1829 if (DECL_P (t))
1831 if (DECL_RTL_SET_P (t))
1832 instantiate_decl_rtl (DECL_RTL (t));
1833 if (TREE_CODE (t) == PARM_DECL && DECL_NAMELESS (t)
1834 && DECL_INCOMING_RTL (t))
1835 instantiate_decl_rtl (DECL_INCOMING_RTL (t));
1836 if ((TREE_CODE (t) == VAR_DECL
1837 || TREE_CODE (t) == RESULT_DECL)
1838 && DECL_HAS_VALUE_EXPR_P (t))
1840 tree v = DECL_VALUE_EXPR (t);
1841 walk_tree (&v, instantiate_expr, NULL, NULL);
1845 return NULL;
1848 /* Subroutine of instantiate_decls: Process all decls in the given
1849 BLOCK node and all its subblocks. */
1851 static void
1852 instantiate_decls_1 (tree let)
1854 tree t;
1856 for (t = BLOCK_VARS (let); t; t = DECL_CHAIN (t))
1858 if (DECL_RTL_SET_P (t))
1859 instantiate_decl_rtl (DECL_RTL (t));
1860 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1862 tree v = DECL_VALUE_EXPR (t);
1863 walk_tree (&v, instantiate_expr, NULL, NULL);
1867 /* Process all subblocks. */
1868 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1869 instantiate_decls_1 (t);
1872 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1873 all virtual registers in their DECL_RTL's. */
1875 static void
1876 instantiate_decls (tree fndecl)
1878 tree decl;
1879 unsigned ix;
1881 /* Process all parameters of the function. */
1882 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = DECL_CHAIN (decl))
1884 instantiate_decl_rtl (DECL_RTL (decl));
1885 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1886 if (DECL_HAS_VALUE_EXPR_P (decl))
1888 tree v = DECL_VALUE_EXPR (decl);
1889 walk_tree (&v, instantiate_expr, NULL, NULL);
1893 if ((decl = DECL_RESULT (fndecl))
1894 && TREE_CODE (decl) == RESULT_DECL)
1896 if (DECL_RTL_SET_P (decl))
1897 instantiate_decl_rtl (DECL_RTL (decl));
1898 if (DECL_HAS_VALUE_EXPR_P (decl))
1900 tree v = DECL_VALUE_EXPR (decl);
1901 walk_tree (&v, instantiate_expr, NULL, NULL);
1905 /* Process the saved static chain if it exists. */
1906 decl = DECL_STRUCT_FUNCTION (fndecl)->static_chain_decl;
1907 if (decl && DECL_HAS_VALUE_EXPR_P (decl))
1908 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl)));
1910 /* Now process all variables defined in the function or its subblocks. */
1911 instantiate_decls_1 (DECL_INITIAL (fndecl));
1913 FOR_EACH_LOCAL_DECL (cfun, ix, decl)
1914 if (DECL_RTL_SET_P (decl))
1915 instantiate_decl_rtl (DECL_RTL (decl));
1916 vec_free (cfun->local_decls);
1919 /* Pass through the INSNS of function FNDECL and convert virtual register
1920 references to hard register references. */
1922 static unsigned int
1923 instantiate_virtual_regs (void)
1925 rtx_insn *insn;
1927 /* Compute the offsets to use for this function. */
1928 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1929 var_offset = STARTING_FRAME_OFFSET;
1930 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1931 out_arg_offset = STACK_POINTER_OFFSET;
1932 #ifdef FRAME_POINTER_CFA_OFFSET
1933 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1934 #else
1935 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1936 #endif
1938 /* Initialize recognition, indicating that volatile is OK. */
1939 init_recog ();
1941 /* Scan through all the insns, instantiating every virtual register still
1942 present. */
1943 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1944 if (INSN_P (insn))
1946 /* These patterns in the instruction stream can never be recognized.
1947 Fortunately, they shouldn't contain virtual registers either. */
1948 if (GET_CODE (PATTERN (insn)) == USE
1949 || GET_CODE (PATTERN (insn)) == CLOBBER
1950 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1951 continue;
1952 else if (DEBUG_INSN_P (insn))
1953 instantiate_virtual_regs_in_rtx (&INSN_VAR_LOCATION (insn));
1954 else
1955 instantiate_virtual_regs_in_insn (insn);
1957 if (insn->deleted ())
1958 continue;
1960 instantiate_virtual_regs_in_rtx (&REG_NOTES (insn));
1962 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1963 if (CALL_P (insn))
1964 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn));
1967 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1968 instantiate_decls (current_function_decl);
1970 targetm.instantiate_decls ();
1972 /* Indicate that, from now on, assign_stack_local should use
1973 frame_pointer_rtx. */
1974 virtuals_instantiated = 1;
1976 return 0;
1979 namespace {
1981 const pass_data pass_data_instantiate_virtual_regs =
1983 RTL_PASS, /* type */
1984 "vregs", /* name */
1985 OPTGROUP_NONE, /* optinfo_flags */
1986 TV_NONE, /* tv_id */
1987 0, /* properties_required */
1988 0, /* properties_provided */
1989 0, /* properties_destroyed */
1990 0, /* todo_flags_start */
1991 0, /* todo_flags_finish */
1994 class pass_instantiate_virtual_regs : public rtl_opt_pass
1996 public:
1997 pass_instantiate_virtual_regs (gcc::context *ctxt)
1998 : rtl_opt_pass (pass_data_instantiate_virtual_regs, ctxt)
2001 /* opt_pass methods: */
2002 virtual unsigned int execute (function *)
2004 return instantiate_virtual_regs ();
2007 }; // class pass_instantiate_virtual_regs
2009 } // anon namespace
2011 rtl_opt_pass *
2012 make_pass_instantiate_virtual_regs (gcc::context *ctxt)
2014 return new pass_instantiate_virtual_regs (ctxt);
2018 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2019 This means a type for which function calls must pass an address to the
2020 function or get an address back from the function.
2021 EXP may be a type node or an expression (whose type is tested). */
2024 aggregate_value_p (const_tree exp, const_tree fntype)
2026 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
2027 int i, regno, nregs;
2028 rtx reg;
2030 if (fntype)
2031 switch (TREE_CODE (fntype))
2033 case CALL_EXPR:
2035 tree fndecl = get_callee_fndecl (fntype);
2036 if (fndecl)
2037 fntype = TREE_TYPE (fndecl);
2038 else if (CALL_EXPR_FN (fntype))
2039 fntype = TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype)));
2040 else
2041 /* For internal functions, assume nothing needs to be
2042 returned in memory. */
2043 return 0;
2045 break;
2046 case FUNCTION_DECL:
2047 fntype = TREE_TYPE (fntype);
2048 break;
2049 case FUNCTION_TYPE:
2050 case METHOD_TYPE:
2051 break;
2052 case IDENTIFIER_NODE:
2053 fntype = NULL_TREE;
2054 break;
2055 default:
2056 /* We don't expect other tree types here. */
2057 gcc_unreachable ();
2060 if (VOID_TYPE_P (type))
2061 return 0;
2063 /* If a record should be passed the same as its first (and only) member
2064 don't pass it as an aggregate. */
2065 if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2066 return aggregate_value_p (first_field (type), fntype);
2068 /* If the front end has decided that this needs to be passed by
2069 reference, do so. */
2070 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
2071 && DECL_BY_REFERENCE (exp))
2072 return 1;
2074 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2075 if (fntype && TREE_ADDRESSABLE (fntype))
2076 return 1;
2078 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2079 and thus can't be returned in registers. */
2080 if (TREE_ADDRESSABLE (type))
2081 return 1;
2083 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
2084 return 1;
2086 if (targetm.calls.return_in_memory (type, fntype))
2087 return 1;
2089 /* Make sure we have suitable call-clobbered regs to return
2090 the value in; if not, we must return it in memory. */
2091 reg = hard_function_value (type, 0, fntype, 0);
2093 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2094 it is OK. */
2095 if (!REG_P (reg))
2096 return 0;
2098 regno = REGNO (reg);
2099 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
2100 for (i = 0; i < nregs; i++)
2101 if (! call_used_regs[regno + i])
2102 return 1;
2104 return 0;
2107 /* Return true if we should assign DECL a pseudo register; false if it
2108 should live on the local stack. */
2110 bool
2111 use_register_for_decl (const_tree decl)
2113 if (!targetm.calls.allocate_stack_slots_for_args ())
2114 return true;
2116 /* Honor volatile. */
2117 if (TREE_SIDE_EFFECTS (decl))
2118 return false;
2120 /* Honor addressability. */
2121 if (TREE_ADDRESSABLE (decl))
2122 return false;
2124 /* Decl is implicitly addressible by bound stores and loads
2125 if it is an aggregate holding bounds. */
2126 if (chkp_function_instrumented_p (current_function_decl)
2127 && TREE_TYPE (decl)
2128 && !BOUNDED_P (decl)
2129 && chkp_type_has_pointer (TREE_TYPE (decl)))
2130 return false;
2132 /* Only register-like things go in registers. */
2133 if (DECL_MODE (decl) == BLKmode)
2134 return false;
2136 /* If -ffloat-store specified, don't put explicit float variables
2137 into registers. */
2138 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2139 propagates values across these stores, and it probably shouldn't. */
2140 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
2141 return false;
2143 /* If we're not interested in tracking debugging information for
2144 this decl, then we can certainly put it in a register. */
2145 if (DECL_IGNORED_P (decl))
2146 return true;
2148 if (optimize)
2149 return true;
2151 if (!DECL_REGISTER (decl))
2152 return false;
2154 switch (TREE_CODE (TREE_TYPE (decl)))
2156 case RECORD_TYPE:
2157 case UNION_TYPE:
2158 case QUAL_UNION_TYPE:
2159 /* When not optimizing, disregard register keyword for variables with
2160 types containing methods, otherwise the methods won't be callable
2161 from the debugger. */
2162 if (TYPE_METHODS (TYPE_MAIN_VARIANT (TREE_TYPE (decl))))
2163 return false;
2164 break;
2165 default:
2166 break;
2169 return true;
2172 /* Structures to communicate between the subroutines of assign_parms.
2173 The first holds data persistent across all parameters, the second
2174 is cleared out for each parameter. */
2176 struct assign_parm_data_all
2178 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2179 should become a job of the target or otherwise encapsulated. */
2180 CUMULATIVE_ARGS args_so_far_v;
2181 cumulative_args_t args_so_far;
2182 struct args_size stack_args_size;
2183 tree function_result_decl;
2184 tree orig_fnargs;
2185 rtx_insn *first_conversion_insn;
2186 rtx_insn *last_conversion_insn;
2187 HOST_WIDE_INT pretend_args_size;
2188 HOST_WIDE_INT extra_pretend_bytes;
2189 int reg_parm_stack_space;
2192 struct assign_parm_data_one
2194 tree nominal_type;
2195 tree passed_type;
2196 rtx entry_parm;
2197 rtx stack_parm;
2198 machine_mode nominal_mode;
2199 machine_mode passed_mode;
2200 machine_mode promoted_mode;
2201 struct locate_and_pad_arg_data locate;
2202 int partial;
2203 BOOL_BITFIELD named_arg : 1;
2204 BOOL_BITFIELD passed_pointer : 1;
2205 BOOL_BITFIELD on_stack : 1;
2206 BOOL_BITFIELD loaded_in_reg : 1;
2209 struct bounds_parm_data
2211 assign_parm_data_one parm_data;
2212 tree bounds_parm;
2213 tree ptr_parm;
2214 rtx ptr_entry;
2215 int bound_no;
2218 /* A subroutine of assign_parms. Initialize ALL. */
2220 static void
2221 assign_parms_initialize_all (struct assign_parm_data_all *all)
2223 tree fntype ATTRIBUTE_UNUSED;
2225 memset (all, 0, sizeof (*all));
2227 fntype = TREE_TYPE (current_function_decl);
2229 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2230 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far_v, fntype, NULL_RTX);
2231 #else
2232 INIT_CUMULATIVE_ARGS (all->args_so_far_v, fntype, NULL_RTX,
2233 current_function_decl, -1);
2234 #endif
2235 all->args_so_far = pack_cumulative_args (&all->args_so_far_v);
2237 #ifdef INCOMING_REG_PARM_STACK_SPACE
2238 all->reg_parm_stack_space
2239 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl);
2240 #endif
2243 /* If ARGS contains entries with complex types, split the entry into two
2244 entries of the component type. Return a new list of substitutions are
2245 needed, else the old list. */
2247 static void
2248 split_complex_args (vec<tree> *args)
2250 unsigned i;
2251 tree p;
2253 FOR_EACH_VEC_ELT (*args, i, p)
2255 tree type = TREE_TYPE (p);
2256 if (TREE_CODE (type) == COMPLEX_TYPE
2257 && targetm.calls.split_complex_arg (type))
2259 tree decl;
2260 tree subtype = TREE_TYPE (type);
2261 bool addressable = TREE_ADDRESSABLE (p);
2263 /* Rewrite the PARM_DECL's type with its component. */
2264 p = copy_node (p);
2265 TREE_TYPE (p) = subtype;
2266 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2267 DECL_MODE (p) = VOIDmode;
2268 DECL_SIZE (p) = NULL;
2269 DECL_SIZE_UNIT (p) = NULL;
2270 /* If this arg must go in memory, put it in a pseudo here.
2271 We can't allow it to go in memory as per normal parms,
2272 because the usual place might not have the imag part
2273 adjacent to the real part. */
2274 DECL_ARTIFICIAL (p) = addressable;
2275 DECL_IGNORED_P (p) = addressable;
2276 TREE_ADDRESSABLE (p) = 0;
2277 layout_decl (p, 0);
2278 (*args)[i] = p;
2280 /* Build a second synthetic decl. */
2281 decl = build_decl (EXPR_LOCATION (p),
2282 PARM_DECL, NULL_TREE, subtype);
2283 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2284 DECL_ARTIFICIAL (decl) = addressable;
2285 DECL_IGNORED_P (decl) = addressable;
2286 layout_decl (decl, 0);
2287 args->safe_insert (++i, decl);
2292 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2293 the hidden struct return argument, and (abi willing) complex args.
2294 Return the new parameter list. */
2296 static vec<tree>
2297 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2299 tree fndecl = current_function_decl;
2300 tree fntype = TREE_TYPE (fndecl);
2301 vec<tree> fnargs = vNULL;
2302 tree arg;
2304 for (arg = DECL_ARGUMENTS (fndecl); arg; arg = DECL_CHAIN (arg))
2305 fnargs.safe_push (arg);
2307 all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2309 /* If struct value address is treated as the first argument, make it so. */
2310 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2311 && ! cfun->returns_pcc_struct
2312 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2314 tree type = build_pointer_type (TREE_TYPE (fntype));
2315 tree decl;
2317 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2318 PARM_DECL, get_identifier (".result_ptr"), type);
2319 DECL_ARG_TYPE (decl) = type;
2320 DECL_ARTIFICIAL (decl) = 1;
2321 DECL_NAMELESS (decl) = 1;
2322 TREE_CONSTANT (decl) = 1;
2324 DECL_CHAIN (decl) = all->orig_fnargs;
2325 all->orig_fnargs = decl;
2326 fnargs.safe_insert (0, decl);
2328 all->function_result_decl = decl;
2330 /* If function is instrumented then bounds of the
2331 passed structure address is the second argument. */
2332 if (chkp_function_instrumented_p (fndecl))
2334 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2335 PARM_DECL, get_identifier (".result_bnd"),
2336 pointer_bounds_type_node);
2337 DECL_ARG_TYPE (decl) = pointer_bounds_type_node;
2338 DECL_ARTIFICIAL (decl) = 1;
2339 DECL_NAMELESS (decl) = 1;
2340 TREE_CONSTANT (decl) = 1;
2342 DECL_CHAIN (decl) = DECL_CHAIN (all->orig_fnargs);
2343 DECL_CHAIN (all->orig_fnargs) = decl;
2344 fnargs.safe_insert (1, decl);
2348 /* If the target wants to split complex arguments into scalars, do so. */
2349 if (targetm.calls.split_complex_arg)
2350 split_complex_args (&fnargs);
2352 return fnargs;
2355 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2356 data for the parameter. Incorporate ABI specifics such as pass-by-
2357 reference and type promotion. */
2359 static void
2360 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2361 struct assign_parm_data_one *data)
2363 tree nominal_type, passed_type;
2364 machine_mode nominal_mode, passed_mode, promoted_mode;
2365 int unsignedp;
2367 memset (data, 0, sizeof (*data));
2369 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2370 if (!cfun->stdarg)
2371 data->named_arg = 1; /* No variadic parms. */
2372 else if (DECL_CHAIN (parm))
2373 data->named_arg = 1; /* Not the last non-variadic parm. */
2374 else if (targetm.calls.strict_argument_naming (all->args_so_far))
2375 data->named_arg = 1; /* Only variadic ones are unnamed. */
2376 else
2377 data->named_arg = 0; /* Treat as variadic. */
2379 nominal_type = TREE_TYPE (parm);
2380 passed_type = DECL_ARG_TYPE (parm);
2382 /* Look out for errors propagating this far. Also, if the parameter's
2383 type is void then its value doesn't matter. */
2384 if (TREE_TYPE (parm) == error_mark_node
2385 /* This can happen after weird syntax errors
2386 or if an enum type is defined among the parms. */
2387 || TREE_CODE (parm) != PARM_DECL
2388 || passed_type == NULL
2389 || VOID_TYPE_P (nominal_type))
2391 nominal_type = passed_type = void_type_node;
2392 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2393 goto egress;
2396 /* Find mode of arg as it is passed, and mode of arg as it should be
2397 during execution of this function. */
2398 passed_mode = TYPE_MODE (passed_type);
2399 nominal_mode = TYPE_MODE (nominal_type);
2401 /* If the parm is to be passed as a transparent union or record, use the
2402 type of the first field for the tests below. We have already verified
2403 that the modes are the same. */
2404 if ((TREE_CODE (passed_type) == UNION_TYPE
2405 || TREE_CODE (passed_type) == RECORD_TYPE)
2406 && TYPE_TRANSPARENT_AGGR (passed_type))
2407 passed_type = TREE_TYPE (first_field (passed_type));
2409 /* See if this arg was passed by invisible reference. */
2410 if (pass_by_reference (&all->args_so_far_v, passed_mode,
2411 passed_type, data->named_arg))
2413 passed_type = nominal_type = build_pointer_type (passed_type);
2414 data->passed_pointer = true;
2415 passed_mode = nominal_mode = TYPE_MODE (nominal_type);
2418 /* Find mode as it is passed by the ABI. */
2419 unsignedp = TYPE_UNSIGNED (passed_type);
2420 promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2421 TREE_TYPE (current_function_decl), 0);
2423 egress:
2424 data->nominal_type = nominal_type;
2425 data->passed_type = passed_type;
2426 data->nominal_mode = nominal_mode;
2427 data->passed_mode = passed_mode;
2428 data->promoted_mode = promoted_mode;
2431 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2433 static void
2434 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2435 struct assign_parm_data_one *data, bool no_rtl)
2437 int varargs_pretend_bytes = 0;
2439 targetm.calls.setup_incoming_varargs (all->args_so_far,
2440 data->promoted_mode,
2441 data->passed_type,
2442 &varargs_pretend_bytes, no_rtl);
2444 /* If the back-end has requested extra stack space, record how much is
2445 needed. Do not change pretend_args_size otherwise since it may be
2446 nonzero from an earlier partial argument. */
2447 if (varargs_pretend_bytes > 0)
2448 all->pretend_args_size = varargs_pretend_bytes;
2451 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2452 the incoming location of the current parameter. */
2454 static void
2455 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2456 struct assign_parm_data_one *data)
2458 HOST_WIDE_INT pretend_bytes = 0;
2459 rtx entry_parm;
2460 bool in_regs;
2462 if (data->promoted_mode == VOIDmode)
2464 data->entry_parm = data->stack_parm = const0_rtx;
2465 return;
2468 entry_parm = targetm.calls.function_incoming_arg (all->args_so_far,
2469 data->promoted_mode,
2470 data->passed_type,
2471 data->named_arg);
2473 if (entry_parm == 0)
2474 data->promoted_mode = data->passed_mode;
2476 /* Determine parm's home in the stack, in case it arrives in the stack
2477 or we should pretend it did. Compute the stack position and rtx where
2478 the argument arrives and its size.
2480 There is one complexity here: If this was a parameter that would
2481 have been passed in registers, but wasn't only because it is
2482 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2483 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2484 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2485 as it was the previous time. */
2486 in_regs = (entry_parm != 0) || POINTER_BOUNDS_TYPE_P (data->passed_type);
2487 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2488 in_regs = true;
2489 #endif
2490 if (!in_regs && !data->named_arg)
2492 if (targetm.calls.pretend_outgoing_varargs_named (all->args_so_far))
2494 rtx tem;
2495 tem = targetm.calls.function_incoming_arg (all->args_so_far,
2496 data->promoted_mode,
2497 data->passed_type, true);
2498 in_regs = tem != NULL;
2502 /* If this parameter was passed both in registers and in the stack, use
2503 the copy on the stack. */
2504 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2505 data->passed_type))
2506 entry_parm = 0;
2508 if (entry_parm)
2510 int partial;
2512 partial = targetm.calls.arg_partial_bytes (all->args_so_far,
2513 data->promoted_mode,
2514 data->passed_type,
2515 data->named_arg);
2516 data->partial = partial;
2518 /* The caller might already have allocated stack space for the
2519 register parameters. */
2520 if (partial != 0 && all->reg_parm_stack_space == 0)
2522 /* Part of this argument is passed in registers and part
2523 is passed on the stack. Ask the prologue code to extend
2524 the stack part so that we can recreate the full value.
2526 PRETEND_BYTES is the size of the registers we need to store.
2527 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2528 stack space that the prologue should allocate.
2530 Internally, gcc assumes that the argument pointer is aligned
2531 to STACK_BOUNDARY bits. This is used both for alignment
2532 optimizations (see init_emit) and to locate arguments that are
2533 aligned to more than PARM_BOUNDARY bits. We must preserve this
2534 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2535 a stack boundary. */
2537 /* We assume at most one partial arg, and it must be the first
2538 argument on the stack. */
2539 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2541 pretend_bytes = partial;
2542 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2544 /* We want to align relative to the actual stack pointer, so
2545 don't include this in the stack size until later. */
2546 all->extra_pretend_bytes = all->pretend_args_size;
2550 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2551 all->reg_parm_stack_space,
2552 entry_parm ? data->partial : 0, current_function_decl,
2553 &all->stack_args_size, &data->locate);
2555 /* Update parm_stack_boundary if this parameter is passed in the
2556 stack. */
2557 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2558 crtl->parm_stack_boundary = data->locate.boundary;
2560 /* Adjust offsets to include the pretend args. */
2561 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2562 data->locate.slot_offset.constant += pretend_bytes;
2563 data->locate.offset.constant += pretend_bytes;
2565 data->entry_parm = entry_parm;
2568 /* A subroutine of assign_parms. If there is actually space on the stack
2569 for this parm, count it in stack_args_size and return true. */
2571 static bool
2572 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2573 struct assign_parm_data_one *data)
2575 /* Bounds are never passed on the stack to keep compatibility
2576 with not instrumented code. */
2577 if (POINTER_BOUNDS_TYPE_P (data->passed_type))
2578 return false;
2579 /* Trivially true if we've no incoming register. */
2580 else if (data->entry_parm == NULL)
2582 /* Also true if we're partially in registers and partially not,
2583 since we've arranged to drop the entire argument on the stack. */
2584 else if (data->partial != 0)
2586 /* Also true if the target says that it's passed in both registers
2587 and on the stack. */
2588 else if (GET_CODE (data->entry_parm) == PARALLEL
2589 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2591 /* Also true if the target says that there's stack allocated for
2592 all register parameters. */
2593 else if (all->reg_parm_stack_space > 0)
2595 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2596 else
2597 return false;
2599 all->stack_args_size.constant += data->locate.size.constant;
2600 if (data->locate.size.var)
2601 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2603 return true;
2606 /* A subroutine of assign_parms. Given that this parameter is allocated
2607 stack space by the ABI, find it. */
2609 static void
2610 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2612 rtx offset_rtx, stack_parm;
2613 unsigned int align, boundary;
2615 /* If we're passing this arg using a reg, make its stack home the
2616 aligned stack slot. */
2617 if (data->entry_parm)
2618 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2619 else
2620 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2622 stack_parm = crtl->args.internal_arg_pointer;
2623 if (offset_rtx != const0_rtx)
2624 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2625 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2627 if (!data->passed_pointer)
2629 set_mem_attributes (stack_parm, parm, 1);
2630 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2631 while promoted mode's size is needed. */
2632 if (data->promoted_mode != BLKmode
2633 && data->promoted_mode != DECL_MODE (parm))
2635 set_mem_size (stack_parm, GET_MODE_SIZE (data->promoted_mode));
2636 if (MEM_EXPR (stack_parm) && MEM_OFFSET_KNOWN_P (stack_parm))
2638 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2639 data->promoted_mode);
2640 if (offset)
2641 set_mem_offset (stack_parm, MEM_OFFSET (stack_parm) - offset);
2646 boundary = data->locate.boundary;
2647 align = BITS_PER_UNIT;
2649 /* If we're padding upward, we know that the alignment of the slot
2650 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2651 intentionally forcing upward padding. Otherwise we have to come
2652 up with a guess at the alignment based on OFFSET_RTX. */
2653 if (data->locate.where_pad != downward || data->entry_parm)
2654 align = boundary;
2655 else if (CONST_INT_P (offset_rtx))
2657 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2658 align = align & -align;
2660 set_mem_align (stack_parm, align);
2662 if (data->entry_parm)
2663 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2665 data->stack_parm = stack_parm;
2668 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2669 always valid and contiguous. */
2671 static void
2672 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2674 rtx entry_parm = data->entry_parm;
2675 rtx stack_parm = data->stack_parm;
2677 /* If this parm was passed part in regs and part in memory, pretend it
2678 arrived entirely in memory by pushing the register-part onto the stack.
2679 In the special case of a DImode or DFmode that is split, we could put
2680 it together in a pseudoreg directly, but for now that's not worth
2681 bothering with. */
2682 if (data->partial != 0)
2684 /* Handle calls that pass values in multiple non-contiguous
2685 locations. The Irix 6 ABI has examples of this. */
2686 if (GET_CODE (entry_parm) == PARALLEL)
2687 emit_group_store (validize_mem (copy_rtx (stack_parm)), entry_parm,
2688 data->passed_type,
2689 int_size_in_bytes (data->passed_type));
2690 else
2692 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2693 move_block_from_reg (REGNO (entry_parm),
2694 validize_mem (copy_rtx (stack_parm)),
2695 data->partial / UNITS_PER_WORD);
2698 entry_parm = stack_parm;
2701 /* If we didn't decide this parm came in a register, by default it came
2702 on the stack. */
2703 else if (entry_parm == NULL)
2704 entry_parm = stack_parm;
2706 /* When an argument is passed in multiple locations, we can't make use
2707 of this information, but we can save some copying if the whole argument
2708 is passed in a single register. */
2709 else if (GET_CODE (entry_parm) == PARALLEL
2710 && data->nominal_mode != BLKmode
2711 && data->passed_mode != BLKmode)
2713 size_t i, len = XVECLEN (entry_parm, 0);
2715 for (i = 0; i < len; i++)
2716 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2717 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2718 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2719 == data->passed_mode)
2720 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2722 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2723 break;
2727 data->entry_parm = entry_parm;
2730 /* A subroutine of assign_parms. Reconstitute any values which were
2731 passed in multiple registers and would fit in a single register. */
2733 static void
2734 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2736 rtx entry_parm = data->entry_parm;
2738 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2739 This can be done with register operations rather than on the
2740 stack, even if we will store the reconstituted parameter on the
2741 stack later. */
2742 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2744 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2745 emit_group_store (parmreg, entry_parm, data->passed_type,
2746 GET_MODE_SIZE (GET_MODE (entry_parm)));
2747 entry_parm = parmreg;
2750 data->entry_parm = entry_parm;
2753 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2754 always valid and properly aligned. */
2756 static void
2757 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2759 rtx stack_parm = data->stack_parm;
2761 /* If we can't trust the parm stack slot to be aligned enough for its
2762 ultimate type, don't use that slot after entry. We'll make another
2763 stack slot, if we need one. */
2764 if (stack_parm
2765 && ((STRICT_ALIGNMENT
2766 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2767 || (data->nominal_type
2768 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2769 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2770 stack_parm = NULL;
2772 /* If parm was passed in memory, and we need to convert it on entry,
2773 don't store it back in that same slot. */
2774 else if (data->entry_parm == stack_parm
2775 && data->nominal_mode != BLKmode
2776 && data->nominal_mode != data->passed_mode)
2777 stack_parm = NULL;
2779 /* If stack protection is in effect for this function, don't leave any
2780 pointers in their passed stack slots. */
2781 else if (crtl->stack_protect_guard
2782 && (flag_stack_protect == 2
2783 || data->passed_pointer
2784 || POINTER_TYPE_P (data->nominal_type)))
2785 stack_parm = NULL;
2787 data->stack_parm = stack_parm;
2790 /* A subroutine of assign_parms. Return true if the current parameter
2791 should be stored as a BLKmode in the current frame. */
2793 static bool
2794 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2796 if (data->nominal_mode == BLKmode)
2797 return true;
2798 if (GET_MODE (data->entry_parm) == BLKmode)
2799 return true;
2801 #ifdef BLOCK_REG_PADDING
2802 /* Only assign_parm_setup_block knows how to deal with register arguments
2803 that are padded at the least significant end. */
2804 if (REG_P (data->entry_parm)
2805 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2806 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2807 == (BYTES_BIG_ENDIAN ? upward : downward)))
2808 return true;
2809 #endif
2811 return false;
2814 /* A subroutine of assign_parms. Arrange for the parameter to be
2815 present and valid in DATA->STACK_RTL. */
2817 static void
2818 assign_parm_setup_block (struct assign_parm_data_all *all,
2819 tree parm, struct assign_parm_data_one *data)
2821 rtx entry_parm = data->entry_parm;
2822 rtx stack_parm = data->stack_parm;
2823 HOST_WIDE_INT size;
2824 HOST_WIDE_INT size_stored;
2826 if (GET_CODE (entry_parm) == PARALLEL)
2827 entry_parm = emit_group_move_into_temps (entry_parm);
2829 size = int_size_in_bytes (data->passed_type);
2830 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2831 if (stack_parm == 0)
2833 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2834 stack_parm = assign_stack_local (BLKmode, size_stored,
2835 DECL_ALIGN (parm));
2836 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2837 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2838 set_mem_attributes (stack_parm, parm, 1);
2841 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2842 calls that pass values in multiple non-contiguous locations. */
2843 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2845 rtx mem;
2847 /* Note that we will be storing an integral number of words.
2848 So we have to be careful to ensure that we allocate an
2849 integral number of words. We do this above when we call
2850 assign_stack_local if space was not allocated in the argument
2851 list. If it was, this will not work if PARM_BOUNDARY is not
2852 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2853 if it becomes a problem. Exception is when BLKmode arrives
2854 with arguments not conforming to word_mode. */
2856 if (data->stack_parm == 0)
2858 else if (GET_CODE (entry_parm) == PARALLEL)
2860 else
2861 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2863 mem = validize_mem (copy_rtx (stack_parm));
2865 /* Handle values in multiple non-contiguous locations. */
2866 if (GET_CODE (entry_parm) == PARALLEL)
2868 push_to_sequence2 (all->first_conversion_insn,
2869 all->last_conversion_insn);
2870 emit_group_store (mem, entry_parm, data->passed_type, size);
2871 all->first_conversion_insn = get_insns ();
2872 all->last_conversion_insn = get_last_insn ();
2873 end_sequence ();
2876 else if (size == 0)
2879 /* If SIZE is that of a mode no bigger than a word, just use
2880 that mode's store operation. */
2881 else if (size <= UNITS_PER_WORD)
2883 machine_mode mode
2884 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2886 if (mode != BLKmode
2887 #ifdef BLOCK_REG_PADDING
2888 && (size == UNITS_PER_WORD
2889 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2890 != (BYTES_BIG_ENDIAN ? upward : downward)))
2891 #endif
2894 rtx reg;
2896 /* We are really truncating a word_mode value containing
2897 SIZE bytes into a value of mode MODE. If such an
2898 operation requires no actual instructions, we can refer
2899 to the value directly in mode MODE, otherwise we must
2900 start with the register in word_mode and explicitly
2901 convert it. */
2902 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2903 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2904 else
2906 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2907 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2909 emit_move_insn (change_address (mem, mode, 0), reg);
2912 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2913 machine must be aligned to the left before storing
2914 to memory. Note that the previous test doesn't
2915 handle all cases (e.g. SIZE == 3). */
2916 else if (size != UNITS_PER_WORD
2917 #ifdef BLOCK_REG_PADDING
2918 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2919 == downward)
2920 #else
2921 && BYTES_BIG_ENDIAN
2922 #endif
2925 rtx tem, x;
2926 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2927 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2929 x = expand_shift (LSHIFT_EXPR, word_mode, reg, by, NULL_RTX, 1);
2930 tem = change_address (mem, word_mode, 0);
2931 emit_move_insn (tem, x);
2933 else
2934 move_block_from_reg (REGNO (entry_parm), mem,
2935 size_stored / UNITS_PER_WORD);
2937 else
2938 move_block_from_reg (REGNO (entry_parm), mem,
2939 size_stored / UNITS_PER_WORD);
2941 else if (data->stack_parm == 0)
2943 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2944 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2945 BLOCK_OP_NORMAL);
2946 all->first_conversion_insn = get_insns ();
2947 all->last_conversion_insn = get_last_insn ();
2948 end_sequence ();
2951 data->stack_parm = stack_parm;
2952 SET_DECL_RTL (parm, stack_parm);
2955 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2956 parameter. Get it there. Perform all ABI specified conversions. */
2958 static void
2959 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2960 struct assign_parm_data_one *data)
2962 rtx parmreg, validated_mem;
2963 rtx equiv_stack_parm;
2964 machine_mode promoted_nominal_mode;
2965 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2966 bool did_conversion = false;
2967 bool need_conversion, moved;
2969 /* Store the parm in a pseudoregister during the function, but we may
2970 need to do it in a wider mode. Using 2 here makes the result
2971 consistent with promote_decl_mode and thus expand_expr_real_1. */
2972 promoted_nominal_mode
2973 = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2974 TREE_TYPE (current_function_decl), 2);
2976 parmreg = gen_reg_rtx (promoted_nominal_mode);
2978 if (!DECL_ARTIFICIAL (parm))
2979 mark_user_reg (parmreg);
2981 /* If this was an item that we received a pointer to,
2982 set DECL_RTL appropriately. */
2983 if (data->passed_pointer)
2985 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2986 set_mem_attributes (x, parm, 1);
2987 SET_DECL_RTL (parm, x);
2989 else
2990 SET_DECL_RTL (parm, parmreg);
2992 assign_parm_remove_parallels (data);
2994 /* Copy the value into the register, thus bridging between
2995 assign_parm_find_data_types and expand_expr_real_1. */
2997 equiv_stack_parm = data->stack_parm;
2998 validated_mem = validize_mem (copy_rtx (data->entry_parm));
3000 need_conversion = (data->nominal_mode != data->passed_mode
3001 || promoted_nominal_mode != data->promoted_mode);
3002 moved = false;
3004 if (need_conversion
3005 && GET_MODE_CLASS (data->nominal_mode) == MODE_INT
3006 && data->nominal_mode == data->passed_mode
3007 && data->nominal_mode == GET_MODE (data->entry_parm))
3009 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3010 mode, by the caller. We now have to convert it to
3011 NOMINAL_MODE, if different. However, PARMREG may be in
3012 a different mode than NOMINAL_MODE if it is being stored
3013 promoted.
3015 If ENTRY_PARM is a hard register, it might be in a register
3016 not valid for operating in its mode (e.g., an odd-numbered
3017 register for a DFmode). In that case, moves are the only
3018 thing valid, so we can't do a convert from there. This
3019 occurs when the calling sequence allow such misaligned
3020 usages.
3022 In addition, the conversion may involve a call, which could
3023 clobber parameters which haven't been copied to pseudo
3024 registers yet.
3026 First, we try to emit an insn which performs the necessary
3027 conversion. We verify that this insn does not clobber any
3028 hard registers. */
3030 enum insn_code icode;
3031 rtx op0, op1;
3033 icode = can_extend_p (promoted_nominal_mode, data->passed_mode,
3034 unsignedp);
3036 op0 = parmreg;
3037 op1 = validated_mem;
3038 if (icode != CODE_FOR_nothing
3039 && insn_operand_matches (icode, 0, op0)
3040 && insn_operand_matches (icode, 1, op1))
3042 enum rtx_code code = unsignedp ? ZERO_EXTEND : SIGN_EXTEND;
3043 rtx_insn *insn, *insns;
3044 rtx t = op1;
3045 HARD_REG_SET hardregs;
3047 start_sequence ();
3048 /* If op1 is a hard register that is likely spilled, first
3049 force it into a pseudo, otherwise combiner might extend
3050 its lifetime too much. */
3051 if (GET_CODE (t) == SUBREG)
3052 t = SUBREG_REG (t);
3053 if (REG_P (t)
3054 && HARD_REGISTER_P (t)
3055 && ! TEST_HARD_REG_BIT (fixed_reg_set, REGNO (t))
3056 && targetm.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t))))
3058 t = gen_reg_rtx (GET_MODE (op1));
3059 emit_move_insn (t, op1);
3061 else
3062 t = op1;
3063 rtx_insn *pat = gen_extend_insn (op0, t, promoted_nominal_mode,
3064 data->passed_mode, unsignedp);
3065 emit_insn (pat);
3066 insns = get_insns ();
3068 moved = true;
3069 CLEAR_HARD_REG_SET (hardregs);
3070 for (insn = insns; insn && moved; insn = NEXT_INSN (insn))
3072 if (INSN_P (insn))
3073 note_stores (PATTERN (insn), record_hard_reg_sets,
3074 &hardregs);
3075 if (!hard_reg_set_empty_p (hardregs))
3076 moved = false;
3079 end_sequence ();
3081 if (moved)
3083 emit_insn (insns);
3084 if (equiv_stack_parm != NULL_RTX)
3085 equiv_stack_parm = gen_rtx_fmt_e (code, GET_MODE (parmreg),
3086 equiv_stack_parm);
3091 if (moved)
3092 /* Nothing to do. */
3094 else if (need_conversion)
3096 /* We did not have an insn to convert directly, or the sequence
3097 generated appeared unsafe. We must first copy the parm to a
3098 pseudo reg, and save the conversion until after all
3099 parameters have been moved. */
3101 int save_tree_used;
3102 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3104 emit_move_insn (tempreg, validated_mem);
3106 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3107 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
3109 if (GET_CODE (tempreg) == SUBREG
3110 && GET_MODE (tempreg) == data->nominal_mode
3111 && REG_P (SUBREG_REG (tempreg))
3112 && data->nominal_mode == data->passed_mode
3113 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
3114 && GET_MODE_SIZE (GET_MODE (tempreg))
3115 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
3117 /* The argument is already sign/zero extended, so note it
3118 into the subreg. */
3119 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
3120 SUBREG_PROMOTED_SET (tempreg, unsignedp);
3123 /* TREE_USED gets set erroneously during expand_assignment. */
3124 save_tree_used = TREE_USED (parm);
3125 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
3126 TREE_USED (parm) = save_tree_used;
3127 all->first_conversion_insn = get_insns ();
3128 all->last_conversion_insn = get_last_insn ();
3129 end_sequence ();
3131 did_conversion = true;
3133 else
3134 emit_move_insn (parmreg, validated_mem);
3136 /* If we were passed a pointer but the actual value can safely live
3137 in a register, retrieve it and use it directly. */
3138 if (data->passed_pointer && TYPE_MODE (TREE_TYPE (parm)) != BLKmode)
3140 /* We can't use nominal_mode, because it will have been set to
3141 Pmode above. We must use the actual mode of the parm. */
3142 if (use_register_for_decl (parm))
3144 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
3145 mark_user_reg (parmreg);
3147 else
3149 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3150 TYPE_MODE (TREE_TYPE (parm)),
3151 TYPE_ALIGN (TREE_TYPE (parm)));
3152 parmreg
3153 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm)),
3154 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm))),
3155 align);
3156 set_mem_attributes (parmreg, parm, 1);
3159 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
3161 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
3162 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
3164 push_to_sequence2 (all->first_conversion_insn,
3165 all->last_conversion_insn);
3166 emit_move_insn (tempreg, DECL_RTL (parm));
3167 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
3168 emit_move_insn (parmreg, tempreg);
3169 all->first_conversion_insn = get_insns ();
3170 all->last_conversion_insn = get_last_insn ();
3171 end_sequence ();
3173 did_conversion = true;
3175 else
3176 emit_move_insn (parmreg, DECL_RTL (parm));
3178 SET_DECL_RTL (parm, parmreg);
3180 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3181 now the parm. */
3182 data->stack_parm = NULL;
3185 /* Mark the register as eliminable if we did no conversion and it was
3186 copied from memory at a fixed offset, and the arg pointer was not
3187 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3188 offset formed an invalid address, such memory-equivalences as we
3189 make here would screw up life analysis for it. */
3190 if (data->nominal_mode == data->passed_mode
3191 && !did_conversion
3192 && data->stack_parm != 0
3193 && MEM_P (data->stack_parm)
3194 && data->locate.offset.var == 0
3195 && reg_mentioned_p (virtual_incoming_args_rtx,
3196 XEXP (data->stack_parm, 0)))
3198 rtx_insn *linsn = get_last_insn ();
3199 rtx_insn *sinsn;
3200 rtx set;
3202 /* Mark complex types separately. */
3203 if (GET_CODE (parmreg) == CONCAT)
3205 machine_mode submode
3206 = GET_MODE_INNER (GET_MODE (parmreg));
3207 int regnor = REGNO (XEXP (parmreg, 0));
3208 int regnoi = REGNO (XEXP (parmreg, 1));
3209 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
3210 rtx stacki = adjust_address_nv (data->stack_parm, submode,
3211 GET_MODE_SIZE (submode));
3213 /* Scan backwards for the set of the real and
3214 imaginary parts. */
3215 for (sinsn = linsn; sinsn != 0;
3216 sinsn = prev_nonnote_insn (sinsn))
3218 set = single_set (sinsn);
3219 if (set == 0)
3220 continue;
3222 if (SET_DEST (set) == regno_reg_rtx [regnoi])
3223 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
3224 else if (SET_DEST (set) == regno_reg_rtx [regnor])
3225 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
3228 else
3229 set_dst_reg_note (linsn, REG_EQUIV, equiv_stack_parm, parmreg);
3232 /* For pointer data type, suggest pointer register. */
3233 if (POINTER_TYPE_P (TREE_TYPE (parm)))
3234 mark_reg_pointer (parmreg,
3235 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
3238 /* A subroutine of assign_parms. Allocate stack space to hold the current
3239 parameter. Get it there. Perform all ABI specified conversions. */
3241 static void
3242 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
3243 struct assign_parm_data_one *data)
3245 /* Value must be stored in the stack slot STACK_PARM during function
3246 execution. */
3247 bool to_conversion = false;
3249 assign_parm_remove_parallels (data);
3251 if (data->promoted_mode != data->nominal_mode)
3253 /* Conversion is required. */
3254 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3256 emit_move_insn (tempreg, validize_mem (copy_rtx (data->entry_parm)));
3258 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3259 to_conversion = true;
3261 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3262 TYPE_UNSIGNED (TREE_TYPE (parm)));
3264 if (data->stack_parm)
3266 int offset = subreg_lowpart_offset (data->nominal_mode,
3267 GET_MODE (data->stack_parm));
3268 /* ??? This may need a big-endian conversion on sparc64. */
3269 data->stack_parm
3270 = adjust_address (data->stack_parm, data->nominal_mode, 0);
3271 if (offset && MEM_OFFSET_KNOWN_P (data->stack_parm))
3272 set_mem_offset (data->stack_parm,
3273 MEM_OFFSET (data->stack_parm) + offset);
3277 if (data->entry_parm != data->stack_parm)
3279 rtx src, dest;
3281 if (data->stack_parm == 0)
3283 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3284 GET_MODE (data->entry_parm),
3285 TYPE_ALIGN (data->passed_type));
3286 data->stack_parm
3287 = assign_stack_local (GET_MODE (data->entry_parm),
3288 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3289 align);
3290 set_mem_attributes (data->stack_parm, parm, 1);
3293 dest = validize_mem (copy_rtx (data->stack_parm));
3294 src = validize_mem (copy_rtx (data->entry_parm));
3296 if (MEM_P (src))
3298 /* Use a block move to handle potentially misaligned entry_parm. */
3299 if (!to_conversion)
3300 push_to_sequence2 (all->first_conversion_insn,
3301 all->last_conversion_insn);
3302 to_conversion = true;
3304 emit_block_move (dest, src,
3305 GEN_INT (int_size_in_bytes (data->passed_type)),
3306 BLOCK_OP_NORMAL);
3308 else
3309 emit_move_insn (dest, src);
3312 if (to_conversion)
3314 all->first_conversion_insn = get_insns ();
3315 all->last_conversion_insn = get_last_insn ();
3316 end_sequence ();
3319 SET_DECL_RTL (parm, data->stack_parm);
3322 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3323 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3325 static void
3326 assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3327 vec<tree> fnargs)
3329 tree parm;
3330 tree orig_fnargs = all->orig_fnargs;
3331 unsigned i = 0;
3333 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3335 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3336 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3338 rtx tmp, real, imag;
3339 machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3341 real = DECL_RTL (fnargs[i]);
3342 imag = DECL_RTL (fnargs[i + 1]);
3343 if (inner != GET_MODE (real))
3345 real = gen_lowpart_SUBREG (inner, real);
3346 imag = gen_lowpart_SUBREG (inner, imag);
3349 if (TREE_ADDRESSABLE (parm))
3351 rtx rmem, imem;
3352 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3353 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3354 DECL_MODE (parm),
3355 TYPE_ALIGN (TREE_TYPE (parm)));
3357 /* split_complex_arg put the real and imag parts in
3358 pseudos. Move them to memory. */
3359 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3360 set_mem_attributes (tmp, parm, 1);
3361 rmem = adjust_address_nv (tmp, inner, 0);
3362 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3363 push_to_sequence2 (all->first_conversion_insn,
3364 all->last_conversion_insn);
3365 emit_move_insn (rmem, real);
3366 emit_move_insn (imem, imag);
3367 all->first_conversion_insn = get_insns ();
3368 all->last_conversion_insn = get_last_insn ();
3369 end_sequence ();
3371 else
3372 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3373 SET_DECL_RTL (parm, tmp);
3375 real = DECL_INCOMING_RTL (fnargs[i]);
3376 imag = DECL_INCOMING_RTL (fnargs[i + 1]);
3377 if (inner != GET_MODE (real))
3379 real = gen_lowpart_SUBREG (inner, real);
3380 imag = gen_lowpart_SUBREG (inner, imag);
3382 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3383 set_decl_incoming_rtl (parm, tmp, false);
3384 i++;
3389 /* Load bounds of PARM from bounds table. */
3390 static void
3391 assign_parm_load_bounds (struct assign_parm_data_one *data,
3392 tree parm,
3393 rtx entry,
3394 unsigned bound_no)
3396 bitmap_iterator bi;
3397 unsigned i, offs = 0;
3398 int bnd_no = -1;
3399 rtx slot = NULL, ptr = NULL;
3401 if (parm)
3403 bitmap slots;
3404 bitmap_obstack_initialize (NULL);
3405 slots = BITMAP_ALLOC (NULL);
3406 chkp_find_bound_slots (TREE_TYPE (parm), slots);
3407 EXECUTE_IF_SET_IN_BITMAP (slots, 0, i, bi)
3409 if (bound_no)
3410 bound_no--;
3411 else
3413 bnd_no = i;
3414 break;
3417 BITMAP_FREE (slots);
3418 bitmap_obstack_release (NULL);
3421 /* We may have bounds not associated with any pointer. */
3422 if (bnd_no != -1)
3423 offs = bnd_no * POINTER_SIZE / BITS_PER_UNIT;
3425 /* Find associated pointer. */
3426 if (bnd_no == -1)
3428 /* If bounds are not associated with any bounds,
3429 then it is passed in a register or special slot. */
3430 gcc_assert (data->entry_parm);
3431 ptr = const0_rtx;
3433 else if (MEM_P (entry))
3434 slot = adjust_address (entry, Pmode, offs);
3435 else if (REG_P (entry))
3436 ptr = gen_rtx_REG (Pmode, REGNO (entry) + bnd_no);
3437 else if (GET_CODE (entry) == PARALLEL)
3438 ptr = chkp_get_value_with_offs (entry, GEN_INT (offs));
3439 else
3440 gcc_unreachable ();
3441 data->entry_parm = targetm.calls.load_bounds_for_arg (slot, ptr,
3442 data->entry_parm);
3445 /* Assign RTL expressions to the function's bounds parameters BNDARGS. */
3447 static void
3448 assign_bounds (vec<bounds_parm_data> &bndargs,
3449 struct assign_parm_data_all &all,
3450 bool assign_regs, bool assign_special,
3451 bool assign_bt)
3453 unsigned i, pass;
3454 bounds_parm_data *pbdata;
3456 if (!bndargs.exists ())
3457 return;
3459 /* We make few passes to store input bounds. Firstly handle bounds
3460 passed in registers. After that we load bounds passed in special
3461 slots. Finally we load bounds from Bounds Table. */
3462 for (pass = 0; pass < 3; pass++)
3463 FOR_EACH_VEC_ELT (bndargs, i, pbdata)
3465 /* Pass 0 => regs only. */
3466 if (pass == 0
3467 && (!assign_regs
3468 ||(!pbdata->parm_data.entry_parm
3469 || GET_CODE (pbdata->parm_data.entry_parm) != REG)))
3470 continue;
3471 /* Pass 1 => slots only. */
3472 else if (pass == 1
3473 && (!assign_special
3474 || (!pbdata->parm_data.entry_parm
3475 || GET_CODE (pbdata->parm_data.entry_parm) == REG)))
3476 continue;
3477 /* Pass 2 => BT only. */
3478 else if (pass == 2
3479 && (!assign_bt
3480 || pbdata->parm_data.entry_parm))
3481 continue;
3483 if (!pbdata->parm_data.entry_parm
3484 || GET_CODE (pbdata->parm_data.entry_parm) != REG)
3485 assign_parm_load_bounds (&pbdata->parm_data, pbdata->ptr_parm,
3486 pbdata->ptr_entry, pbdata->bound_no);
3488 set_decl_incoming_rtl (pbdata->bounds_parm,
3489 pbdata->parm_data.entry_parm, false);
3491 if (assign_parm_setup_block_p (&pbdata->parm_data))
3492 assign_parm_setup_block (&all, pbdata->bounds_parm,
3493 &pbdata->parm_data);
3494 else if (pbdata->parm_data.passed_pointer
3495 || use_register_for_decl (pbdata->bounds_parm))
3496 assign_parm_setup_reg (&all, pbdata->bounds_parm,
3497 &pbdata->parm_data);
3498 else
3499 assign_parm_setup_stack (&all, pbdata->bounds_parm,
3500 &pbdata->parm_data);
3504 /* Assign RTL expressions to the function's parameters. This may involve
3505 copying them into registers and using those registers as the DECL_RTL. */
3507 static void
3508 assign_parms (tree fndecl)
3510 struct assign_parm_data_all all;
3511 tree parm;
3512 vec<tree> fnargs;
3513 unsigned i, bound_no = 0;
3514 tree last_arg = NULL;
3515 rtx last_arg_entry = NULL;
3516 vec<bounds_parm_data> bndargs = vNULL;
3517 bounds_parm_data bdata;
3519 crtl->args.internal_arg_pointer
3520 = targetm.calls.internal_arg_pointer ();
3522 assign_parms_initialize_all (&all);
3523 fnargs = assign_parms_augmented_arg_list (&all);
3525 FOR_EACH_VEC_ELT (fnargs, i, parm)
3527 struct assign_parm_data_one data;
3529 /* Extract the type of PARM; adjust it according to ABI. */
3530 assign_parm_find_data_types (&all, parm, &data);
3532 /* Early out for errors and void parameters. */
3533 if (data.passed_mode == VOIDmode)
3535 SET_DECL_RTL (parm, const0_rtx);
3536 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3537 continue;
3540 /* Estimate stack alignment from parameter alignment. */
3541 if (SUPPORTS_STACK_ALIGNMENT)
3543 unsigned int align
3544 = targetm.calls.function_arg_boundary (data.promoted_mode,
3545 data.passed_type);
3546 align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3547 align);
3548 if (TYPE_ALIGN (data.nominal_type) > align)
3549 align = MINIMUM_ALIGNMENT (data.nominal_type,
3550 TYPE_MODE (data.nominal_type),
3551 TYPE_ALIGN (data.nominal_type));
3552 if (crtl->stack_alignment_estimated < align)
3554 gcc_assert (!crtl->stack_realign_processed);
3555 crtl->stack_alignment_estimated = align;
3559 /* Find out where the parameter arrives in this function. */
3560 assign_parm_find_entry_rtl (&all, &data);
3562 /* Find out where stack space for this parameter might be. */
3563 if (assign_parm_is_stack_parm (&all, &data))
3565 assign_parm_find_stack_rtl (parm, &data);
3566 assign_parm_adjust_entry_rtl (&data);
3568 if (!POINTER_BOUNDS_TYPE_P (data.passed_type))
3570 /* Remember where last non bounds arg was passed in case
3571 we have to load associated bounds for it from Bounds
3572 Table. */
3573 last_arg = parm;
3574 last_arg_entry = data.entry_parm;
3575 bound_no = 0;
3577 /* Record permanently how this parm was passed. */
3578 if (data.passed_pointer)
3580 rtx incoming_rtl
3581 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data.passed_type)),
3582 data.entry_parm);
3583 set_decl_incoming_rtl (parm, incoming_rtl, true);
3585 else
3586 set_decl_incoming_rtl (parm, data.entry_parm, false);
3588 /* Boudns should be loaded in the particular order to
3589 have registers allocated correctly. Collect info about
3590 input bounds and load them later. */
3591 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3593 /* Expect bounds in instrumented functions only. */
3594 gcc_assert (chkp_function_instrumented_p (fndecl));
3596 bdata.parm_data = data;
3597 bdata.bounds_parm = parm;
3598 bdata.ptr_parm = last_arg;
3599 bdata.ptr_entry = last_arg_entry;
3600 bdata.bound_no = bound_no;
3601 bndargs.safe_push (bdata);
3603 else
3605 assign_parm_adjust_stack_rtl (&data);
3607 if (assign_parm_setup_block_p (&data))
3608 assign_parm_setup_block (&all, parm, &data);
3609 else if (data.passed_pointer || use_register_for_decl (parm))
3610 assign_parm_setup_reg (&all, parm, &data);
3611 else
3612 assign_parm_setup_stack (&all, parm, &data);
3615 if (cfun->stdarg && !DECL_CHAIN (parm))
3617 int pretend_bytes = 0;
3619 assign_parms_setup_varargs (&all, &data, false);
3621 if (chkp_function_instrumented_p (fndecl))
3623 /* We expect this is the last parm. Otherwise it is wrong
3624 to assign bounds right now. */
3625 gcc_assert (i == (fnargs.length () - 1));
3626 assign_bounds (bndargs, all, true, false, false);
3627 targetm.calls.setup_incoming_vararg_bounds (all.args_so_far,
3628 data.promoted_mode,
3629 data.passed_type,
3630 &pretend_bytes,
3631 false);
3632 assign_bounds (bndargs, all, false, true, true);
3633 bndargs.release ();
3637 /* Update info on where next arg arrives in registers. */
3638 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3639 data.passed_type, data.named_arg);
3641 if (POINTER_BOUNDS_TYPE_P (data.passed_type))
3642 bound_no++;
3645 assign_bounds (bndargs, all, true, true, true);
3646 bndargs.release ();
3648 if (targetm.calls.split_complex_arg)
3649 assign_parms_unsplit_complex (&all, fnargs);
3651 fnargs.release ();
3653 /* Output all parameter conversion instructions (possibly including calls)
3654 now that all parameters have been copied out of hard registers. */
3655 emit_insn (all.first_conversion_insn);
3657 /* Estimate reload stack alignment from scalar return mode. */
3658 if (SUPPORTS_STACK_ALIGNMENT)
3660 if (DECL_RESULT (fndecl))
3662 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3663 machine_mode mode = TYPE_MODE (type);
3665 if (mode != BLKmode
3666 && mode != VOIDmode
3667 && !AGGREGATE_TYPE_P (type))
3669 unsigned int align = GET_MODE_ALIGNMENT (mode);
3670 if (crtl->stack_alignment_estimated < align)
3672 gcc_assert (!crtl->stack_realign_processed);
3673 crtl->stack_alignment_estimated = align;
3679 /* If we are receiving a struct value address as the first argument, set up
3680 the RTL for the function result. As this might require code to convert
3681 the transmitted address to Pmode, we do this here to ensure that possible
3682 preliminary conversions of the address have been emitted already. */
3683 if (all.function_result_decl)
3685 tree result = DECL_RESULT (current_function_decl);
3686 rtx addr = DECL_RTL (all.function_result_decl);
3687 rtx x;
3689 if (DECL_BY_REFERENCE (result))
3691 SET_DECL_VALUE_EXPR (result, all.function_result_decl);
3692 x = addr;
3694 else
3696 SET_DECL_VALUE_EXPR (result,
3697 build1 (INDIRECT_REF, TREE_TYPE (result),
3698 all.function_result_decl));
3699 addr = convert_memory_address (Pmode, addr);
3700 x = gen_rtx_MEM (DECL_MODE (result), addr);
3701 set_mem_attributes (x, result, 1);
3704 DECL_HAS_VALUE_EXPR_P (result) = 1;
3706 SET_DECL_RTL (result, x);
3709 /* We have aligned all the args, so add space for the pretend args. */
3710 crtl->args.pretend_args_size = all.pretend_args_size;
3711 all.stack_args_size.constant += all.extra_pretend_bytes;
3712 crtl->args.size = all.stack_args_size.constant;
3714 /* Adjust function incoming argument size for alignment and
3715 minimum length. */
3717 crtl->args.size = MAX (crtl->args.size, all.reg_parm_stack_space);
3718 crtl->args.size = CEIL_ROUND (crtl->args.size,
3719 PARM_BOUNDARY / BITS_PER_UNIT);
3721 if (ARGS_GROW_DOWNWARD)
3723 crtl->args.arg_offset_rtx
3724 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3725 : expand_expr (size_diffop (all.stack_args_size.var,
3726 size_int (-all.stack_args_size.constant)),
3727 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3729 else
3730 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3732 /* See how many bytes, if any, of its args a function should try to pop
3733 on return. */
3735 crtl->args.pops_args = targetm.calls.return_pops_args (fndecl,
3736 TREE_TYPE (fndecl),
3737 crtl->args.size);
3739 /* For stdarg.h function, save info about
3740 regs and stack space used by the named args. */
3742 crtl->args.info = all.args_so_far_v;
3744 /* Set the rtx used for the function return value. Put this in its
3745 own variable so any optimizers that need this information don't have
3746 to include tree.h. Do this here so it gets done when an inlined
3747 function gets output. */
3749 crtl->return_rtx
3750 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3751 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3753 /* If scalar return value was computed in a pseudo-reg, or was a named
3754 return value that got dumped to the stack, copy that to the hard
3755 return register. */
3756 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3758 tree decl_result = DECL_RESULT (fndecl);
3759 rtx decl_rtl = DECL_RTL (decl_result);
3761 if (REG_P (decl_rtl)
3762 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3763 : DECL_REGISTER (decl_result))
3765 rtx real_decl_rtl;
3767 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3768 fndecl, true);
3769 if (chkp_function_instrumented_p (fndecl))
3770 crtl->return_bnd
3771 = targetm.calls.chkp_function_value_bounds (TREE_TYPE (decl_result),
3772 fndecl, true);
3773 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3774 /* The delay slot scheduler assumes that crtl->return_rtx
3775 holds the hard register containing the return value, not a
3776 temporary pseudo. */
3777 crtl->return_rtx = real_decl_rtl;
3782 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3783 For all seen types, gimplify their sizes. */
3785 static tree
3786 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3788 tree t = *tp;
3790 *walk_subtrees = 0;
3791 if (TYPE_P (t))
3793 if (POINTER_TYPE_P (t))
3794 *walk_subtrees = 1;
3795 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3796 && !TYPE_SIZES_GIMPLIFIED (t))
3798 gimplify_type_sizes (t, (gimple_seq *) data);
3799 *walk_subtrees = 1;
3803 return NULL;
3806 /* Gimplify the parameter list for current_function_decl. This involves
3807 evaluating SAVE_EXPRs of variable sized parameters and generating code
3808 to implement callee-copies reference parameters. Returns a sequence of
3809 statements to add to the beginning of the function. */
3811 gimple_seq
3812 gimplify_parameters (void)
3814 struct assign_parm_data_all all;
3815 tree parm;
3816 gimple_seq stmts = NULL;
3817 vec<tree> fnargs;
3818 unsigned i;
3820 assign_parms_initialize_all (&all);
3821 fnargs = assign_parms_augmented_arg_list (&all);
3823 FOR_EACH_VEC_ELT (fnargs, i, parm)
3825 struct assign_parm_data_one data;
3827 /* Extract the type of PARM; adjust it according to ABI. */
3828 assign_parm_find_data_types (&all, parm, &data);
3830 /* Early out for errors and void parameters. */
3831 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3832 continue;
3834 /* Update info on where next arg arrives in registers. */
3835 targetm.calls.function_arg_advance (all.args_so_far, data.promoted_mode,
3836 data.passed_type, data.named_arg);
3838 /* ??? Once upon a time variable_size stuffed parameter list
3839 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3840 turned out to be less than manageable in the gimple world.
3841 Now we have to hunt them down ourselves. */
3842 walk_tree_without_duplicates (&data.passed_type,
3843 gimplify_parm_type, &stmts);
3845 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3847 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3848 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3851 if (data.passed_pointer)
3853 tree type = TREE_TYPE (data.passed_type);
3854 if (reference_callee_copied (&all.args_so_far_v, TYPE_MODE (type),
3855 type, data.named_arg))
3857 tree local, t;
3859 /* For constant-sized objects, this is trivial; for
3860 variable-sized objects, we have to play games. */
3861 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3862 && !(flag_stack_check == GENERIC_STACK_CHECK
3863 && compare_tree_int (DECL_SIZE_UNIT (parm),
3864 STACK_CHECK_MAX_VAR_SIZE) > 0))
3866 local = create_tmp_var (type, get_name (parm));
3867 DECL_IGNORED_P (local) = 0;
3868 /* If PARM was addressable, move that flag over
3869 to the local copy, as its address will be taken,
3870 not the PARMs. Keep the parms address taken
3871 as we'll query that flag during gimplification. */
3872 if (TREE_ADDRESSABLE (parm))
3873 TREE_ADDRESSABLE (local) = 1;
3874 else if (TREE_CODE (type) == COMPLEX_TYPE
3875 || TREE_CODE (type) == VECTOR_TYPE)
3876 DECL_GIMPLE_REG_P (local) = 1;
3878 else
3880 tree ptr_type, addr;
3882 ptr_type = build_pointer_type (type);
3883 addr = create_tmp_reg (ptr_type, get_name (parm));
3884 DECL_IGNORED_P (addr) = 0;
3885 local = build_fold_indirect_ref (addr);
3887 t = builtin_decl_explicit (BUILT_IN_ALLOCA_WITH_ALIGN);
3888 t = build_call_expr (t, 2, DECL_SIZE_UNIT (parm),
3889 size_int (DECL_ALIGN (parm)));
3891 /* The call has been built for a variable-sized object. */
3892 CALL_ALLOCA_FOR_VAR_P (t) = 1;
3893 t = fold_convert (ptr_type, t);
3894 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3895 gimplify_and_add (t, &stmts);
3898 gimplify_assign (local, parm, &stmts);
3900 SET_DECL_VALUE_EXPR (parm, local);
3901 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3906 fnargs.release ();
3908 return stmts;
3911 /* Compute the size and offset from the start of the stacked arguments for a
3912 parm passed in mode PASSED_MODE and with type TYPE.
3914 INITIAL_OFFSET_PTR points to the current offset into the stacked
3915 arguments.
3917 The starting offset and size for this parm are returned in
3918 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3919 nonzero, the offset is that of stack slot, which is returned in
3920 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3921 padding required from the initial offset ptr to the stack slot.
3923 IN_REGS is nonzero if the argument will be passed in registers. It will
3924 never be set if REG_PARM_STACK_SPACE is not defined.
3926 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3927 for arguments which are passed in registers.
3929 FNDECL is the function in which the argument was defined.
3931 There are two types of rounding that are done. The first, controlled by
3932 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3933 argument list to be aligned to the specific boundary (in bits). This
3934 rounding affects the initial and starting offsets, but not the argument
3935 size.
3937 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3938 optionally rounds the size of the parm to PARM_BOUNDARY. The
3939 initial offset is not affected by this rounding, while the size always
3940 is and the starting offset may be. */
3942 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3943 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3944 callers pass in the total size of args so far as
3945 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3947 void
3948 locate_and_pad_parm (machine_mode passed_mode, tree type, int in_regs,
3949 int reg_parm_stack_space, int partial,
3950 tree fndecl ATTRIBUTE_UNUSED,
3951 struct args_size *initial_offset_ptr,
3952 struct locate_and_pad_arg_data *locate)
3954 tree sizetree;
3955 enum direction where_pad;
3956 unsigned int boundary, round_boundary;
3957 int part_size_in_regs;
3959 /* If we have found a stack parm before we reach the end of the
3960 area reserved for registers, skip that area. */
3961 if (! in_regs)
3963 if (reg_parm_stack_space > 0)
3965 if (initial_offset_ptr->var)
3967 initial_offset_ptr->var
3968 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3969 ssize_int (reg_parm_stack_space));
3970 initial_offset_ptr->constant = 0;
3972 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3973 initial_offset_ptr->constant = reg_parm_stack_space;
3977 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3979 sizetree
3980 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3981 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3982 boundary = targetm.calls.function_arg_boundary (passed_mode, type);
3983 round_boundary = targetm.calls.function_arg_round_boundary (passed_mode,
3984 type);
3985 locate->where_pad = where_pad;
3987 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3988 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3989 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3991 locate->boundary = boundary;
3993 if (SUPPORTS_STACK_ALIGNMENT)
3995 /* stack_alignment_estimated can't change after stack has been
3996 realigned. */
3997 if (crtl->stack_alignment_estimated < boundary)
3999 if (!crtl->stack_realign_processed)
4000 crtl->stack_alignment_estimated = boundary;
4001 else
4003 /* If stack is realigned and stack alignment value
4004 hasn't been finalized, it is OK not to increase
4005 stack_alignment_estimated. The bigger alignment
4006 requirement is recorded in stack_alignment_needed
4007 below. */
4008 gcc_assert (!crtl->stack_realign_finalized
4009 && crtl->stack_realign_needed);
4014 /* Remember if the outgoing parameter requires extra alignment on the
4015 calling function side. */
4016 if (crtl->stack_alignment_needed < boundary)
4017 crtl->stack_alignment_needed = boundary;
4018 if (crtl->preferred_stack_boundary < boundary)
4019 crtl->preferred_stack_boundary = boundary;
4021 if (ARGS_GROW_DOWNWARD)
4023 locate->slot_offset.constant = -initial_offset_ptr->constant;
4024 if (initial_offset_ptr->var)
4025 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
4026 initial_offset_ptr->var);
4029 tree s2 = sizetree;
4030 if (where_pad != none
4031 && (!tree_fits_uhwi_p (sizetree)
4032 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4033 s2 = round_up (s2, round_boundary / BITS_PER_UNIT);
4034 SUB_PARM_SIZE (locate->slot_offset, s2);
4037 locate->slot_offset.constant += part_size_in_regs;
4039 if (!in_regs || reg_parm_stack_space > 0)
4040 pad_to_arg_alignment (&locate->slot_offset, boundary,
4041 &locate->alignment_pad);
4043 locate->size.constant = (-initial_offset_ptr->constant
4044 - locate->slot_offset.constant);
4045 if (initial_offset_ptr->var)
4046 locate->size.var = size_binop (MINUS_EXPR,
4047 size_binop (MINUS_EXPR,
4048 ssize_int (0),
4049 initial_offset_ptr->var),
4050 locate->slot_offset.var);
4052 /* Pad_below needs the pre-rounded size to know how much to pad
4053 below. */
4054 locate->offset = locate->slot_offset;
4055 if (where_pad == downward)
4056 pad_below (&locate->offset, passed_mode, sizetree);
4059 else
4061 if (!in_regs || reg_parm_stack_space > 0)
4062 pad_to_arg_alignment (initial_offset_ptr, boundary,
4063 &locate->alignment_pad);
4064 locate->slot_offset = *initial_offset_ptr;
4066 #ifdef PUSH_ROUNDING
4067 if (passed_mode != BLKmode)
4068 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
4069 #endif
4071 /* Pad_below needs the pre-rounded size to know how much to pad below
4072 so this must be done before rounding up. */
4073 locate->offset = locate->slot_offset;
4074 if (where_pad == downward)
4075 pad_below (&locate->offset, passed_mode, sizetree);
4077 if (where_pad != none
4078 && (!tree_fits_uhwi_p (sizetree)
4079 || (tree_to_uhwi (sizetree) * BITS_PER_UNIT) % round_boundary))
4080 sizetree = round_up (sizetree, round_boundary / BITS_PER_UNIT);
4082 ADD_PARM_SIZE (locate->size, sizetree);
4084 locate->size.constant -= part_size_in_regs;
4087 #ifdef FUNCTION_ARG_OFFSET
4088 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
4089 #endif
4092 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4093 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4095 static void
4096 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
4097 struct args_size *alignment_pad)
4099 tree save_var = NULL_TREE;
4100 HOST_WIDE_INT save_constant = 0;
4101 int boundary_in_bytes = boundary / BITS_PER_UNIT;
4102 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
4104 #ifdef SPARC_STACK_BOUNDARY_HACK
4105 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4106 the real alignment of %sp. However, when it does this, the
4107 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4108 if (SPARC_STACK_BOUNDARY_HACK)
4109 sp_offset = 0;
4110 #endif
4112 if (boundary > PARM_BOUNDARY)
4114 save_var = offset_ptr->var;
4115 save_constant = offset_ptr->constant;
4118 alignment_pad->var = NULL_TREE;
4119 alignment_pad->constant = 0;
4121 if (boundary > BITS_PER_UNIT)
4123 if (offset_ptr->var)
4125 tree sp_offset_tree = ssize_int (sp_offset);
4126 tree offset = size_binop (PLUS_EXPR,
4127 ARGS_SIZE_TREE (*offset_ptr),
4128 sp_offset_tree);
4129 tree rounded;
4130 if (ARGS_GROW_DOWNWARD)
4131 rounded = round_down (offset, boundary / BITS_PER_UNIT);
4132 else
4133 rounded = round_up (offset, boundary / BITS_PER_UNIT);
4135 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
4136 /* ARGS_SIZE_TREE includes constant term. */
4137 offset_ptr->constant = 0;
4138 if (boundary > PARM_BOUNDARY)
4139 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
4140 save_var);
4142 else
4144 offset_ptr->constant = -sp_offset +
4145 (ARGS_GROW_DOWNWARD
4146 ? FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes)
4147 : CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes));
4149 if (boundary > PARM_BOUNDARY)
4150 alignment_pad->constant = offset_ptr->constant - save_constant;
4155 static void
4156 pad_below (struct args_size *offset_ptr, machine_mode passed_mode, tree sizetree)
4158 if (passed_mode != BLKmode)
4160 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
4161 offset_ptr->constant
4162 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
4163 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
4164 - GET_MODE_SIZE (passed_mode));
4166 else
4168 if (TREE_CODE (sizetree) != INTEGER_CST
4169 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
4171 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4172 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
4173 /* Add it in. */
4174 ADD_PARM_SIZE (*offset_ptr, s2);
4175 SUB_PARM_SIZE (*offset_ptr, sizetree);
4181 /* True if register REGNO was alive at a place where `setjmp' was
4182 called and was set more than once or is an argument. Such regs may
4183 be clobbered by `longjmp'. */
4185 static bool
4186 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
4188 /* There appear to be cases where some local vars never reach the
4189 backend but have bogus regnos. */
4190 if (regno >= max_reg_num ())
4191 return false;
4193 return ((REG_N_SETS (regno) > 1
4194 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun)),
4195 regno))
4196 && REGNO_REG_SET_P (setjmp_crosses, regno));
4199 /* Walk the tree of blocks describing the binding levels within a
4200 function and warn about variables the might be killed by setjmp or
4201 vfork. This is done after calling flow_analysis before register
4202 allocation since that will clobber the pseudo-regs to hard
4203 regs. */
4205 static void
4206 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
4208 tree decl, sub;
4210 for (decl = BLOCK_VARS (block); decl; decl = DECL_CHAIN (decl))
4212 if (TREE_CODE (decl) == VAR_DECL
4213 && DECL_RTL_SET_P (decl)
4214 && REG_P (DECL_RTL (decl))
4215 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4216 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
4217 " %<longjmp%> or %<vfork%>", decl);
4220 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
4221 setjmp_vars_warning (setjmp_crosses, sub);
4224 /* Do the appropriate part of setjmp_vars_warning
4225 but for arguments instead of local variables. */
4227 static void
4228 setjmp_args_warning (bitmap setjmp_crosses)
4230 tree decl;
4231 for (decl = DECL_ARGUMENTS (current_function_decl);
4232 decl; decl = DECL_CHAIN (decl))
4233 if (DECL_RTL (decl) != 0
4234 && REG_P (DECL_RTL (decl))
4235 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
4236 warning (OPT_Wclobbered,
4237 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4238 decl);
4241 /* Generate warning messages for variables live across setjmp. */
4243 void
4244 generate_setjmp_warnings (void)
4246 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
4248 if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS
4249 || bitmap_empty_p (setjmp_crosses))
4250 return;
4252 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
4253 setjmp_args_warning (setjmp_crosses);
4257 /* Reverse the order of elements in the fragment chain T of blocks,
4258 and return the new head of the chain (old last element).
4259 In addition to that clear BLOCK_SAME_RANGE flags when needed
4260 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4261 its super fragment origin. */
4263 static tree
4264 block_fragments_nreverse (tree t)
4266 tree prev = 0, block, next, prev_super = 0;
4267 tree super = BLOCK_SUPERCONTEXT (t);
4268 if (BLOCK_FRAGMENT_ORIGIN (super))
4269 super = BLOCK_FRAGMENT_ORIGIN (super);
4270 for (block = t; block; block = next)
4272 next = BLOCK_FRAGMENT_CHAIN (block);
4273 BLOCK_FRAGMENT_CHAIN (block) = prev;
4274 if ((prev && !BLOCK_SAME_RANGE (prev))
4275 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block))
4276 != prev_super))
4277 BLOCK_SAME_RANGE (block) = 0;
4278 prev_super = BLOCK_SUPERCONTEXT (block);
4279 BLOCK_SUPERCONTEXT (block) = super;
4280 prev = block;
4282 t = BLOCK_FRAGMENT_ORIGIN (t);
4283 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t))
4284 != prev_super)
4285 BLOCK_SAME_RANGE (t) = 0;
4286 BLOCK_SUPERCONTEXT (t) = super;
4287 return prev;
4290 /* Reverse the order of elements in the chain T of blocks,
4291 and return the new head of the chain (old last element).
4292 Also do the same on subblocks and reverse the order of elements
4293 in BLOCK_FRAGMENT_CHAIN as well. */
4295 static tree
4296 blocks_nreverse_all (tree t)
4298 tree prev = 0, block, next;
4299 for (block = t; block; block = next)
4301 next = BLOCK_CHAIN (block);
4302 BLOCK_CHAIN (block) = prev;
4303 if (BLOCK_FRAGMENT_CHAIN (block)
4304 && BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE)
4306 BLOCK_FRAGMENT_CHAIN (block)
4307 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block));
4308 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block)))
4309 BLOCK_SAME_RANGE (block) = 0;
4311 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4312 prev = block;
4314 return prev;
4318 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4319 and create duplicate blocks. */
4320 /* ??? Need an option to either create block fragments or to create
4321 abstract origin duplicates of a source block. It really depends
4322 on what optimization has been performed. */
4324 void
4325 reorder_blocks (void)
4327 tree block = DECL_INITIAL (current_function_decl);
4329 if (block == NULL_TREE)
4330 return;
4332 auto_vec<tree, 10> block_stack;
4334 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4335 clear_block_marks (block);
4337 /* Prune the old trees away, so that they don't get in the way. */
4338 BLOCK_SUBBLOCKS (block) = NULL_TREE;
4339 BLOCK_CHAIN (block) = NULL_TREE;
4341 /* Recreate the block tree from the note nesting. */
4342 reorder_blocks_1 (get_insns (), block, &block_stack);
4343 BLOCK_SUBBLOCKS (block) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block));
4346 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4348 void
4349 clear_block_marks (tree block)
4351 while (block)
4353 TREE_ASM_WRITTEN (block) = 0;
4354 clear_block_marks (BLOCK_SUBBLOCKS (block));
4355 block = BLOCK_CHAIN (block);
4359 static void
4360 reorder_blocks_1 (rtx_insn *insns, tree current_block,
4361 vec<tree> *p_block_stack)
4363 rtx_insn *insn;
4364 tree prev_beg = NULL_TREE, prev_end = NULL_TREE;
4366 for (insn = insns; insn; insn = NEXT_INSN (insn))
4368 if (NOTE_P (insn))
4370 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
4372 tree block = NOTE_BLOCK (insn);
4373 tree origin;
4375 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block) == NULL_TREE);
4376 origin = block;
4378 if (prev_end)
4379 BLOCK_SAME_RANGE (prev_end) = 0;
4380 prev_end = NULL_TREE;
4382 /* If we have seen this block before, that means it now
4383 spans multiple address regions. Create a new fragment. */
4384 if (TREE_ASM_WRITTEN (block))
4386 tree new_block = copy_node (block);
4388 BLOCK_SAME_RANGE (new_block) = 0;
4389 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
4390 BLOCK_FRAGMENT_CHAIN (new_block)
4391 = BLOCK_FRAGMENT_CHAIN (origin);
4392 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
4394 NOTE_BLOCK (insn) = new_block;
4395 block = new_block;
4398 if (prev_beg == current_block && prev_beg)
4399 BLOCK_SAME_RANGE (block) = 1;
4401 prev_beg = origin;
4403 BLOCK_SUBBLOCKS (block) = 0;
4404 TREE_ASM_WRITTEN (block) = 1;
4405 /* When there's only one block for the entire function,
4406 current_block == block and we mustn't do this, it
4407 will cause infinite recursion. */
4408 if (block != current_block)
4410 tree super;
4411 if (block != origin)
4412 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block
4413 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4414 (origin))
4415 == current_block);
4416 if (p_block_stack->is_empty ())
4417 super = current_block;
4418 else
4420 super = p_block_stack->last ();
4421 gcc_assert (super == current_block
4422 || BLOCK_FRAGMENT_ORIGIN (super)
4423 == current_block);
4425 BLOCK_SUPERCONTEXT (block) = super;
4426 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
4427 BLOCK_SUBBLOCKS (current_block) = block;
4428 current_block = origin;
4430 p_block_stack->safe_push (block);
4432 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
4434 NOTE_BLOCK (insn) = p_block_stack->pop ();
4435 current_block = BLOCK_SUPERCONTEXT (current_block);
4436 if (BLOCK_FRAGMENT_ORIGIN (current_block))
4437 current_block = BLOCK_FRAGMENT_ORIGIN (current_block);
4438 prev_beg = NULL_TREE;
4439 prev_end = BLOCK_SAME_RANGE (NOTE_BLOCK (insn))
4440 ? NOTE_BLOCK (insn) : NULL_TREE;
4443 else
4445 prev_beg = NULL_TREE;
4446 if (prev_end)
4447 BLOCK_SAME_RANGE (prev_end) = 0;
4448 prev_end = NULL_TREE;
4453 /* Reverse the order of elements in the chain T of blocks,
4454 and return the new head of the chain (old last element). */
4456 tree
4457 blocks_nreverse (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 prev = block;
4466 return prev;
4469 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4470 by modifying the last node in chain 1 to point to chain 2. */
4472 tree
4473 block_chainon (tree op1, tree op2)
4475 tree t1;
4477 if (!op1)
4478 return op2;
4479 if (!op2)
4480 return op1;
4482 for (t1 = op1; BLOCK_CHAIN (t1); t1 = BLOCK_CHAIN (t1))
4483 continue;
4484 BLOCK_CHAIN (t1) = op2;
4486 #ifdef ENABLE_TREE_CHECKING
4488 tree t2;
4489 for (t2 = op2; t2; t2 = BLOCK_CHAIN (t2))
4490 gcc_assert (t2 != t1);
4492 #endif
4494 return op1;
4497 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4498 non-NULL, list them all into VECTOR, in a depth-first preorder
4499 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4500 blocks. */
4502 static int
4503 all_blocks (tree block, tree *vector)
4505 int n_blocks = 0;
4507 while (block)
4509 TREE_ASM_WRITTEN (block) = 0;
4511 /* Record this block. */
4512 if (vector)
4513 vector[n_blocks] = block;
4515 ++n_blocks;
4517 /* Record the subblocks, and their subblocks... */
4518 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
4519 vector ? vector + n_blocks : 0);
4520 block = BLOCK_CHAIN (block);
4523 return n_blocks;
4526 /* Return a vector containing all the blocks rooted at BLOCK. The
4527 number of elements in the vector is stored in N_BLOCKS_P. The
4528 vector is dynamically allocated; it is the caller's responsibility
4529 to call `free' on the pointer returned. */
4531 static tree *
4532 get_block_vector (tree block, int *n_blocks_p)
4534 tree *block_vector;
4536 *n_blocks_p = all_blocks (block, NULL);
4537 block_vector = XNEWVEC (tree, *n_blocks_p);
4538 all_blocks (block, block_vector);
4540 return block_vector;
4543 static GTY(()) int next_block_index = 2;
4545 /* Set BLOCK_NUMBER for all the blocks in FN. */
4547 void
4548 number_blocks (tree fn)
4550 int i;
4551 int n_blocks;
4552 tree *block_vector;
4554 /* For SDB and XCOFF debugging output, we start numbering the blocks
4555 from 1 within each function, rather than keeping a running
4556 count. */
4557 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4558 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
4559 next_block_index = 1;
4560 #endif
4562 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
4564 /* The top-level BLOCK isn't numbered at all. */
4565 for (i = 1; i < n_blocks; ++i)
4566 /* We number the blocks from two. */
4567 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4569 free (block_vector);
4571 return;
4574 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4576 DEBUG_FUNCTION tree
4577 debug_find_var_in_block_tree (tree var, tree block)
4579 tree t;
4581 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4582 if (t == var)
4583 return block;
4585 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4587 tree ret = debug_find_var_in_block_tree (var, t);
4588 if (ret)
4589 return ret;
4592 return NULL_TREE;
4595 /* Keep track of whether we're in a dummy function context. If we are,
4596 we don't want to invoke the set_current_function hook, because we'll
4597 get into trouble if the hook calls target_reinit () recursively or
4598 when the initial initialization is not yet complete. */
4600 static bool in_dummy_function;
4602 /* Invoke the target hook when setting cfun. Update the optimization options
4603 if the function uses different options than the default. */
4605 static void
4606 invoke_set_current_function_hook (tree fndecl)
4608 if (!in_dummy_function)
4610 tree opts = ((fndecl)
4611 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4612 : optimization_default_node);
4614 if (!opts)
4615 opts = optimization_default_node;
4617 /* Change optimization options if needed. */
4618 if (optimization_current_node != opts)
4620 optimization_current_node = opts;
4621 cl_optimization_restore (&global_options, TREE_OPTIMIZATION (opts));
4624 targetm.set_current_function (fndecl);
4625 this_fn_optabs = this_target_optabs;
4627 if (opts != optimization_default_node)
4629 init_tree_optimization_optabs (opts);
4630 if (TREE_OPTIMIZATION_OPTABS (opts))
4631 this_fn_optabs = (struct target_optabs *)
4632 TREE_OPTIMIZATION_OPTABS (opts);
4637 /* cfun should never be set directly; use this function. */
4639 void
4640 set_cfun (struct function *new_cfun)
4642 if (cfun != new_cfun)
4644 cfun = new_cfun;
4645 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4649 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4651 static vec<function_p> cfun_stack;
4653 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4654 current_function_decl accordingly. */
4656 void
4657 push_cfun (struct function *new_cfun)
4659 gcc_assert ((!cfun && !current_function_decl)
4660 || (cfun && current_function_decl == cfun->decl));
4661 cfun_stack.safe_push (cfun);
4662 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4663 set_cfun (new_cfun);
4666 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4668 void
4669 pop_cfun (void)
4671 struct function *new_cfun = cfun_stack.pop ();
4672 /* When in_dummy_function, we do have a cfun but current_function_decl is
4673 NULL. We also allow pushing NULL cfun and subsequently changing
4674 current_function_decl to something else and have both restored by
4675 pop_cfun. */
4676 gcc_checking_assert (in_dummy_function
4677 || !cfun
4678 || current_function_decl == cfun->decl);
4679 set_cfun (new_cfun);
4680 current_function_decl = new_cfun ? new_cfun->decl : NULL_TREE;
4683 /* Return value of funcdef and increase it. */
4685 get_next_funcdef_no (void)
4687 return funcdef_no++;
4690 /* Return value of funcdef. */
4692 get_last_funcdef_no (void)
4694 return funcdef_no;
4697 /* Allocate a function structure for FNDECL and set its contents
4698 to the defaults. Set cfun to the newly-allocated object.
4699 Some of the helper functions invoked during initialization assume
4700 that cfun has already been set. Therefore, assign the new object
4701 directly into cfun and invoke the back end hook explicitly at the
4702 very end, rather than initializing a temporary and calling set_cfun
4703 on it.
4705 ABSTRACT_P is true if this is a function that will never be seen by
4706 the middle-end. Such functions are front-end concepts (like C++
4707 function templates) that do not correspond directly to functions
4708 placed in object files. */
4710 void
4711 allocate_struct_function (tree fndecl, bool abstract_p)
4713 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4715 cfun = ggc_cleared_alloc<function> ();
4717 init_eh_for_function ();
4719 if (init_machine_status)
4720 cfun->machine = (*init_machine_status) ();
4722 #ifdef OVERRIDE_ABI_FORMAT
4723 OVERRIDE_ABI_FORMAT (fndecl);
4724 #endif
4726 if (fndecl != NULL_TREE)
4728 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4729 cfun->decl = fndecl;
4730 current_function_funcdef_no = get_next_funcdef_no ();
4733 invoke_set_current_function_hook (fndecl);
4735 if (fndecl != NULL_TREE)
4737 tree result = DECL_RESULT (fndecl);
4738 if (!abstract_p && aggregate_value_p (result, fndecl))
4740 #ifdef PCC_STATIC_STRUCT_RETURN
4741 cfun->returns_pcc_struct = 1;
4742 #endif
4743 cfun->returns_struct = 1;
4746 cfun->stdarg = stdarg_p (fntype);
4748 /* Assume all registers in stdarg functions need to be saved. */
4749 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4750 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4752 /* ??? This could be set on a per-function basis by the front-end
4753 but is this worth the hassle? */
4754 cfun->can_throw_non_call_exceptions = flag_non_call_exceptions;
4755 cfun->can_delete_dead_exceptions = flag_delete_dead_exceptions;
4757 if (!profile_flag && !flag_instrument_function_entry_exit)
4758 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl) = 1;
4762 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4763 instead of just setting it. */
4765 void
4766 push_struct_function (tree fndecl)
4768 /* When in_dummy_function we might be in the middle of a pop_cfun and
4769 current_function_decl and cfun may not match. */
4770 gcc_assert (in_dummy_function
4771 || (!cfun && !current_function_decl)
4772 || (cfun && current_function_decl == cfun->decl));
4773 cfun_stack.safe_push (cfun);
4774 current_function_decl = fndecl;
4775 allocate_struct_function (fndecl, false);
4778 /* Reset crtl and other non-struct-function variables to defaults as
4779 appropriate for emitting rtl at the start of a function. */
4781 static void
4782 prepare_function_start (void)
4784 gcc_assert (!get_last_insn ());
4785 init_temp_slots ();
4786 init_emit ();
4787 init_varasm_status ();
4788 init_expr ();
4789 default_rtl_profile ();
4791 if (flag_stack_usage_info)
4793 cfun->su = ggc_cleared_alloc<stack_usage> ();
4794 cfun->su->static_stack_size = -1;
4797 cse_not_expected = ! optimize;
4799 /* Caller save not needed yet. */
4800 caller_save_needed = 0;
4802 /* We haven't done register allocation yet. */
4803 reg_renumber = 0;
4805 /* Indicate that we have not instantiated virtual registers yet. */
4806 virtuals_instantiated = 0;
4808 /* Indicate that we want CONCATs now. */
4809 generating_concat_p = 1;
4811 /* Indicate we have no need of a frame pointer yet. */
4812 frame_pointer_needed = 0;
4815 void
4816 push_dummy_function (bool with_decl)
4818 tree fn_decl, fn_type, fn_result_decl;
4820 gcc_assert (!in_dummy_function);
4821 in_dummy_function = true;
4823 if (with_decl)
4825 fn_type = build_function_type_list (void_type_node, NULL_TREE);
4826 fn_decl = build_decl (UNKNOWN_LOCATION, FUNCTION_DECL, NULL_TREE,
4827 fn_type);
4828 fn_result_decl = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
4829 NULL_TREE, void_type_node);
4830 DECL_RESULT (fn_decl) = fn_result_decl;
4832 else
4833 fn_decl = NULL_TREE;
4835 push_struct_function (fn_decl);
4838 /* Initialize the rtl expansion mechanism so that we can do simple things
4839 like generate sequences. This is used to provide a context during global
4840 initialization of some passes. You must call expand_dummy_function_end
4841 to exit this context. */
4843 void
4844 init_dummy_function_start (void)
4846 push_dummy_function (false);
4847 prepare_function_start ();
4850 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4851 and initialize static variables for generating RTL for the statements
4852 of the function. */
4854 void
4855 init_function_start (tree subr)
4857 if (subr && DECL_STRUCT_FUNCTION (subr))
4858 set_cfun (DECL_STRUCT_FUNCTION (subr));
4859 else
4860 allocate_struct_function (subr, false);
4862 /* Initialize backend, if needed. */
4863 initialize_rtl ();
4865 prepare_function_start ();
4866 decide_function_section (subr);
4868 /* Warn if this value is an aggregate type,
4869 regardless of which calling convention we are using for it. */
4870 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4871 warning (OPT_Waggregate_return, "function returns an aggregate");
4874 /* Expand code to verify the stack_protect_guard. This is invoked at
4875 the end of a function to be protected. */
4877 #ifndef HAVE_stack_protect_test
4878 # define HAVE_stack_protect_test 0
4879 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4880 #endif
4882 void
4883 stack_protect_epilogue (void)
4885 tree guard_decl = targetm.stack_protect_guard ();
4886 rtx_code_label *label = gen_label_rtx ();
4887 rtx x, y, tmp;
4889 x = expand_normal (crtl->stack_protect_guard);
4890 y = expand_normal (guard_decl);
4892 /* Allow the target to compare Y with X without leaking either into
4893 a register. */
4894 switch (HAVE_stack_protect_test != 0)
4896 case 1:
4897 tmp = gen_stack_protect_test (x, y, label);
4898 if (tmp)
4900 emit_insn (tmp);
4901 break;
4903 /* FALLTHRU */
4905 default:
4906 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4907 break;
4910 /* The noreturn predictor has been moved to the tree level. The rtl-level
4911 predictors estimate this branch about 20%, which isn't enough to get
4912 things moved out of line. Since this is the only extant case of adding
4913 a noreturn function at the rtl level, it doesn't seem worth doing ought
4914 except adding the prediction by hand. */
4915 tmp = get_last_insn ();
4916 if (JUMP_P (tmp))
4917 predict_insn_def (as_a <rtx_insn *> (tmp), PRED_NORETURN, TAKEN);
4919 expand_call (targetm.stack_protect_fail (), NULL_RTX, /*ignore=*/true);
4920 free_temp_slots ();
4921 emit_label (label);
4924 /* Start the RTL for a new function, and set variables used for
4925 emitting RTL.
4926 SUBR is the FUNCTION_DECL node.
4927 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4928 the function's parameters, which must be run at any return statement. */
4930 void
4931 expand_function_start (tree subr)
4933 /* Make sure volatile mem refs aren't considered
4934 valid operands of arithmetic insns. */
4935 init_recog_no_volatile ();
4937 crtl->profile
4938 = (profile_flag
4939 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4941 crtl->limit_stack
4942 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4944 /* Make the label for return statements to jump to. Do not special
4945 case machines with special return instructions -- they will be
4946 handled later during jump, ifcvt, or epilogue creation. */
4947 return_label = gen_label_rtx ();
4949 /* Initialize rtx used to return the value. */
4950 /* Do this before assign_parms so that we copy the struct value address
4951 before any library calls that assign parms might generate. */
4953 /* Decide whether to return the value in memory or in a register. */
4954 if (aggregate_value_p (DECL_RESULT (subr), subr))
4956 /* Returning something that won't go in a register. */
4957 rtx value_address = 0;
4959 #ifdef PCC_STATIC_STRUCT_RETURN
4960 if (cfun->returns_pcc_struct)
4962 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4963 value_address = assemble_static_space (size);
4965 else
4966 #endif
4968 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4969 /* Expect to be passed the address of a place to store the value.
4970 If it is passed as an argument, assign_parms will take care of
4971 it. */
4972 if (sv)
4974 value_address = gen_reg_rtx (Pmode);
4975 emit_move_insn (value_address, sv);
4978 if (value_address)
4980 rtx x = value_address;
4981 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4983 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4984 set_mem_attributes (x, DECL_RESULT (subr), 1);
4986 SET_DECL_RTL (DECL_RESULT (subr), x);
4989 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4990 /* If return mode is void, this decl rtl should not be used. */
4991 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4992 else
4994 /* Compute the return values into a pseudo reg, which we will copy
4995 into the true return register after the cleanups are done. */
4996 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4997 if (TYPE_MODE (return_type) != BLKmode
4998 && targetm.calls.return_in_msb (return_type))
4999 /* expand_function_end will insert the appropriate padding in
5000 this case. Use the return value's natural (unpadded) mode
5001 within the function proper. */
5002 SET_DECL_RTL (DECL_RESULT (subr),
5003 gen_reg_rtx (TYPE_MODE (return_type)));
5004 else
5006 /* In order to figure out what mode to use for the pseudo, we
5007 figure out what the mode of the eventual return register will
5008 actually be, and use that. */
5009 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
5011 /* Structures that are returned in registers are not
5012 aggregate_value_p, so we may see a PARALLEL or a REG. */
5013 if (REG_P (hard_reg))
5014 SET_DECL_RTL (DECL_RESULT (subr),
5015 gen_reg_rtx (GET_MODE (hard_reg)));
5016 else
5018 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
5019 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
5023 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5024 result to the real return register(s). */
5025 DECL_REGISTER (DECL_RESULT (subr)) = 1;
5027 if (chkp_function_instrumented_p (current_function_decl))
5029 tree return_type = TREE_TYPE (DECL_RESULT (subr));
5030 rtx bounds = targetm.calls.chkp_function_value_bounds (return_type,
5031 subr, 1);
5032 SET_DECL_BOUNDS_RTL (DECL_RESULT (subr), bounds);
5036 /* Initialize rtx for parameters and local variables.
5037 In some cases this requires emitting insns. */
5038 assign_parms (subr);
5040 /* If function gets a static chain arg, store it. */
5041 if (cfun->static_chain_decl)
5043 tree parm = cfun->static_chain_decl;
5044 rtx local, chain;
5045 rtx_insn *insn;
5047 local = gen_reg_rtx (Pmode);
5048 chain = targetm.calls.static_chain (current_function_decl, true);
5050 set_decl_incoming_rtl (parm, chain, false);
5051 SET_DECL_RTL (parm, local);
5052 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
5054 insn = emit_move_insn (local, chain);
5056 /* Mark the register as eliminable, similar to parameters. */
5057 if (MEM_P (chain)
5058 && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
5059 set_dst_reg_note (insn, REG_EQUIV, chain, local);
5061 /* If we aren't optimizing, save the static chain onto the stack. */
5062 if (!optimize)
5064 tree saved_static_chain_decl
5065 = build_decl (DECL_SOURCE_LOCATION (parm), VAR_DECL,
5066 DECL_NAME (parm), TREE_TYPE (parm));
5067 rtx saved_static_chain_rtx
5068 = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5069 SET_DECL_RTL (saved_static_chain_decl, saved_static_chain_rtx);
5070 emit_move_insn (saved_static_chain_rtx, chain);
5071 SET_DECL_VALUE_EXPR (parm, saved_static_chain_decl);
5072 DECL_HAS_VALUE_EXPR_P (parm) = 1;
5076 /* If the function receives a non-local goto, then store the
5077 bits we need to restore the frame pointer. */
5078 if (cfun->nonlocal_goto_save_area)
5080 tree t_save;
5081 rtx r_save;
5083 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
5084 gcc_assert (DECL_RTL_SET_P (var));
5086 t_save = build4 (ARRAY_REF,
5087 TREE_TYPE (TREE_TYPE (cfun->nonlocal_goto_save_area)),
5088 cfun->nonlocal_goto_save_area,
5089 integer_zero_node, NULL_TREE, NULL_TREE);
5090 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
5091 gcc_assert (GET_MODE (r_save) == Pmode);
5093 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
5094 update_nonlocal_goto_save_area ();
5097 /* The following was moved from init_function_start.
5098 The move is supposed to make sdb output more accurate. */
5099 /* Indicate the beginning of the function body,
5100 as opposed to parm setup. */
5101 emit_note (NOTE_INSN_FUNCTION_BEG);
5103 gcc_assert (NOTE_P (get_last_insn ()));
5105 parm_birth_insn = get_last_insn ();
5107 if (crtl->profile)
5109 #ifdef PROFILE_HOOK
5110 PROFILE_HOOK (current_function_funcdef_no);
5111 #endif
5114 /* If we are doing generic stack checking, the probe should go here. */
5115 if (flag_stack_check == GENERIC_STACK_CHECK)
5116 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
5119 void
5120 pop_dummy_function (void)
5122 pop_cfun ();
5123 in_dummy_function = false;
5126 /* Undo the effects of init_dummy_function_start. */
5127 void
5128 expand_dummy_function_end (void)
5130 gcc_assert (in_dummy_function);
5132 /* End any sequences that failed to be closed due to syntax errors. */
5133 while (in_sequence_p ())
5134 end_sequence ();
5136 /* Outside function body, can't compute type's actual size
5137 until next function's body starts. */
5139 free_after_parsing (cfun);
5140 free_after_compilation (cfun);
5141 pop_dummy_function ();
5144 /* Helper for diddle_return_value. */
5146 void
5147 diddle_return_value_1 (void (*doit) (rtx, void *), void *arg, rtx outgoing)
5149 if (! outgoing)
5150 return;
5152 if (REG_P (outgoing))
5153 (*doit) (outgoing, arg);
5154 else if (GET_CODE (outgoing) == PARALLEL)
5156 int i;
5158 for (i = 0; i < XVECLEN (outgoing, 0); i++)
5160 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
5162 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
5163 (*doit) (x, arg);
5168 /* Call DOIT for each hard register used as a return value from
5169 the current function. */
5171 void
5172 diddle_return_value (void (*doit) (rtx, void *), void *arg)
5174 diddle_return_value_1 (doit, arg, crtl->return_bnd);
5175 diddle_return_value_1 (doit, arg, crtl->return_rtx);
5178 static void
5179 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5181 emit_clobber (reg);
5184 void
5185 clobber_return_register (void)
5187 diddle_return_value (do_clobber_return_reg, NULL);
5189 /* In case we do use pseudo to return value, clobber it too. */
5190 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5192 tree decl_result = DECL_RESULT (current_function_decl);
5193 rtx decl_rtl = DECL_RTL (decl_result);
5194 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
5196 do_clobber_return_reg (decl_rtl, NULL);
5201 static void
5202 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
5204 emit_use (reg);
5207 static void
5208 use_return_register (void)
5210 diddle_return_value (do_use_return_reg, NULL);
5213 /* Set the location of the insn chain starting at INSN to LOC. */
5215 static void
5216 set_insn_locations (rtx_insn *insn, int loc)
5218 while (insn != NULL)
5220 if (INSN_P (insn))
5221 INSN_LOCATION (insn) = loc;
5222 insn = NEXT_INSN (insn);
5226 /* Generate RTL for the end of the current function. */
5228 void
5229 expand_function_end (void)
5231 /* If arg_pointer_save_area was referenced only from a nested
5232 function, we will not have initialized it yet. Do that now. */
5233 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
5234 get_arg_pointer_save_area ();
5236 /* If we are doing generic stack checking and this function makes calls,
5237 do a stack probe at the start of the function to ensure we have enough
5238 space for another stack frame. */
5239 if (flag_stack_check == GENERIC_STACK_CHECK)
5241 rtx_insn *insn, *seq;
5243 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5244 if (CALL_P (insn))
5246 rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
5247 start_sequence ();
5248 if (STACK_CHECK_MOVING_SP)
5249 anti_adjust_stack_and_probe (max_frame_size, true);
5250 else
5251 probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
5252 seq = get_insns ();
5253 end_sequence ();
5254 set_insn_locations (seq, prologue_location);
5255 emit_insn_before (seq, stack_check_probe_note);
5256 break;
5260 /* End any sequences that failed to be closed due to syntax errors. */
5261 while (in_sequence_p ())
5262 end_sequence ();
5264 clear_pending_stack_adjust ();
5265 do_pending_stack_adjust ();
5267 /* Output a linenumber for the end of the function.
5268 SDB depends on this. */
5269 set_curr_insn_location (input_location);
5271 /* Before the return label (if any), clobber the return
5272 registers so that they are not propagated live to the rest of
5273 the function. This can only happen with functions that drop
5274 through; if there had been a return statement, there would
5275 have either been a return rtx, or a jump to the return label.
5277 We delay actual code generation after the current_function_value_rtx
5278 is computed. */
5279 rtx_insn *clobber_after = get_last_insn ();
5281 /* Output the label for the actual return from the function. */
5282 emit_label (return_label);
5284 if (targetm_common.except_unwind_info (&global_options) == UI_SJLJ)
5286 /* Let except.c know where it should emit the call to unregister
5287 the function context for sjlj exceptions. */
5288 if (flag_exceptions)
5289 sjlj_emit_function_exit_after (get_last_insn ());
5291 else
5293 /* We want to ensure that instructions that may trap are not
5294 moved into the epilogue by scheduling, because we don't
5295 always emit unwind information for the epilogue. */
5296 if (cfun->can_throw_non_call_exceptions)
5297 emit_insn (gen_blockage ());
5300 /* If this is an implementation of throw, do what's necessary to
5301 communicate between __builtin_eh_return and the epilogue. */
5302 expand_eh_return ();
5304 /* If scalar return value was computed in a pseudo-reg, or was a named
5305 return value that got dumped to the stack, copy that to the hard
5306 return register. */
5307 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
5309 tree decl_result = DECL_RESULT (current_function_decl);
5310 rtx decl_rtl = DECL_RTL (decl_result);
5312 if (REG_P (decl_rtl)
5313 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
5314 : DECL_REGISTER (decl_result))
5316 rtx real_decl_rtl = crtl->return_rtx;
5318 /* This should be set in assign_parms. */
5319 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
5321 /* If this is a BLKmode structure being returned in registers,
5322 then use the mode computed in expand_return. Note that if
5323 decl_rtl is memory, then its mode may have been changed,
5324 but that crtl->return_rtx has not. */
5325 if (GET_MODE (real_decl_rtl) == BLKmode)
5326 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
5328 /* If a non-BLKmode return value should be padded at the least
5329 significant end of the register, shift it left by the appropriate
5330 amount. BLKmode results are handled using the group load/store
5331 machinery. */
5332 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
5333 && REG_P (real_decl_rtl)
5334 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
5336 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
5337 REGNO (real_decl_rtl)),
5338 decl_rtl);
5339 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
5341 /* If a named return value dumped decl_return to memory, then
5342 we may need to re-do the PROMOTE_MODE signed/unsigned
5343 extension. */
5344 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
5346 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
5347 promote_function_mode (TREE_TYPE (decl_result),
5348 GET_MODE (decl_rtl), &unsignedp,
5349 TREE_TYPE (current_function_decl), 1);
5351 convert_move (real_decl_rtl, decl_rtl, unsignedp);
5353 else if (GET_CODE (real_decl_rtl) == PARALLEL)
5355 /* If expand_function_start has created a PARALLEL for decl_rtl,
5356 move the result to the real return registers. Otherwise, do
5357 a group load from decl_rtl for a named return. */
5358 if (GET_CODE (decl_rtl) == PARALLEL)
5359 emit_group_move (real_decl_rtl, decl_rtl);
5360 else
5361 emit_group_load (real_decl_rtl, decl_rtl,
5362 TREE_TYPE (decl_result),
5363 int_size_in_bytes (TREE_TYPE (decl_result)));
5365 /* In the case of complex integer modes smaller than a word, we'll
5366 need to generate some non-trivial bitfield insertions. Do that
5367 on a pseudo and not the hard register. */
5368 else if (GET_CODE (decl_rtl) == CONCAT
5369 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
5370 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
5372 int old_generating_concat_p;
5373 rtx tmp;
5375 old_generating_concat_p = generating_concat_p;
5376 generating_concat_p = 0;
5377 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
5378 generating_concat_p = old_generating_concat_p;
5380 emit_move_insn (tmp, decl_rtl);
5381 emit_move_insn (real_decl_rtl, tmp);
5383 else
5384 emit_move_insn (real_decl_rtl, decl_rtl);
5388 /* If returning a structure, arrange to return the address of the value
5389 in a place where debuggers expect to find it.
5391 If returning a structure PCC style,
5392 the caller also depends on this value.
5393 And cfun->returns_pcc_struct is not necessarily set. */
5394 if ((cfun->returns_struct || cfun->returns_pcc_struct)
5395 && !targetm.calls.omit_struct_return_reg)
5397 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
5398 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
5399 rtx outgoing;
5401 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
5402 type = TREE_TYPE (type);
5403 else
5404 value_address = XEXP (value_address, 0);
5406 outgoing = targetm.calls.function_value (build_pointer_type (type),
5407 current_function_decl, true);
5409 /* Mark this as a function return value so integrate will delete the
5410 assignment and USE below when inlining this function. */
5411 REG_FUNCTION_VALUE_P (outgoing) = 1;
5413 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5414 value_address = convert_memory_address (GET_MODE (outgoing),
5415 value_address);
5417 emit_move_insn (outgoing, value_address);
5419 /* Show return register used to hold result (in this case the address
5420 of the result. */
5421 crtl->return_rtx = outgoing;
5424 /* Emit the actual code to clobber return register. Don't emit
5425 it if clobber_after is a barrier, then the previous basic block
5426 certainly doesn't fall thru into the exit block. */
5427 if (!BARRIER_P (clobber_after))
5429 start_sequence ();
5430 clobber_return_register ();
5431 rtx_insn *seq = get_insns ();
5432 end_sequence ();
5434 emit_insn_after (seq, clobber_after);
5437 /* Output the label for the naked return from the function. */
5438 if (naked_return_label)
5439 emit_label (naked_return_label);
5441 /* @@@ This is a kludge. We want to ensure that instructions that
5442 may trap are not moved into the epilogue by scheduling, because
5443 we don't always emit unwind information for the epilogue. */
5444 if (cfun->can_throw_non_call_exceptions
5445 && targetm_common.except_unwind_info (&global_options) != UI_SJLJ)
5446 emit_insn (gen_blockage ());
5448 /* If stack protection is enabled for this function, check the guard. */
5449 if (crtl->stack_protect_guard)
5450 stack_protect_epilogue ();
5452 /* If we had calls to alloca, and this machine needs
5453 an accurate stack pointer to exit the function,
5454 insert some code to save and restore the stack pointer. */
5455 if (! EXIT_IGNORE_STACK
5456 && cfun->calls_alloca)
5458 rtx tem = 0;
5460 start_sequence ();
5461 emit_stack_save (SAVE_FUNCTION, &tem);
5462 rtx_insn *seq = get_insns ();
5463 end_sequence ();
5464 emit_insn_before (seq, parm_birth_insn);
5466 emit_stack_restore (SAVE_FUNCTION, tem);
5469 /* ??? This should no longer be necessary since stupid is no longer with
5470 us, but there are some parts of the compiler (eg reload_combine, and
5471 sh mach_dep_reorg) that still try and compute their own lifetime info
5472 instead of using the general framework. */
5473 use_return_register ();
5477 get_arg_pointer_save_area (void)
5479 rtx ret = arg_pointer_save_area;
5481 if (! ret)
5483 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
5484 arg_pointer_save_area = ret;
5487 if (! crtl->arg_pointer_save_area_init)
5489 /* Save the arg pointer at the beginning of the function. The
5490 generated stack slot may not be a valid memory address, so we
5491 have to check it and fix it if necessary. */
5492 start_sequence ();
5493 emit_move_insn (validize_mem (copy_rtx (ret)),
5494 crtl->args.internal_arg_pointer);
5495 rtx_insn *seq = get_insns ();
5496 end_sequence ();
5498 push_topmost_sequence ();
5499 emit_insn_after (seq, entry_of_function ());
5500 pop_topmost_sequence ();
5502 crtl->arg_pointer_save_area_init = true;
5505 return ret;
5508 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5509 for the first time. */
5511 static void
5512 record_insns (rtx_insn *insns, rtx end, hash_table<insn_cache_hasher> **hashp)
5514 rtx_insn *tmp;
5515 hash_table<insn_cache_hasher> *hash = *hashp;
5517 if (hash == NULL)
5518 *hashp = hash = hash_table<insn_cache_hasher>::create_ggc (17);
5520 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
5522 rtx *slot = hash->find_slot (tmp, INSERT);
5523 gcc_assert (*slot == NULL);
5524 *slot = tmp;
5528 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5529 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5530 insn, then record COPY as well. */
5532 void
5533 maybe_copy_prologue_epilogue_insn (rtx insn, rtx copy)
5535 hash_table<insn_cache_hasher> *hash;
5536 rtx *slot;
5538 hash = epilogue_insn_hash;
5539 if (!hash || !hash->find (insn))
5541 hash = prologue_insn_hash;
5542 if (!hash || !hash->find (insn))
5543 return;
5546 slot = hash->find_slot (copy, INSERT);
5547 gcc_assert (*slot == NULL);
5548 *slot = copy;
5551 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5552 we can be running after reorg, SEQUENCE rtl is possible. */
5554 static bool
5555 contains (const_rtx insn, hash_table<insn_cache_hasher> *hash)
5557 if (hash == NULL)
5558 return false;
5560 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
5562 rtx_sequence *seq = as_a <rtx_sequence *> (PATTERN (insn));
5563 int i;
5564 for (i = seq->len () - 1; i >= 0; i--)
5565 if (hash->find (seq->element (i)))
5566 return true;
5567 return false;
5570 return hash->find (const_cast<rtx> (insn)) != NULL;
5574 prologue_epilogue_contains (const_rtx insn)
5576 if (contains (insn, prologue_insn_hash))
5577 return 1;
5578 if (contains (insn, epilogue_insn_hash))
5579 return 1;
5580 return 0;
5583 /* Insert use of return register before the end of BB. */
5585 static void
5586 emit_use_return_register_into_block (basic_block bb)
5588 start_sequence ();
5589 use_return_register ();
5590 rtx_insn *seq = get_insns ();
5591 end_sequence ();
5592 rtx_insn *insn = BB_END (bb);
5593 if (HAVE_cc0 && reg_mentioned_p (cc0_rtx, PATTERN (insn)))
5594 insn = prev_cc0_setter (insn);
5596 emit_insn_before (seq, insn);
5600 /* Create a return pattern, either simple_return or return, depending on
5601 simple_p. */
5603 static rtx_insn *
5604 gen_return_pattern (bool simple_p)
5606 return (simple_p
5607 ? targetm.gen_simple_return ()
5608 : targetm.gen_return ());
5611 /* Insert an appropriate return pattern at the end of block BB. This
5612 also means updating block_for_insn appropriately. SIMPLE_P is
5613 the same as in gen_return_pattern and passed to it. */
5615 void
5616 emit_return_into_block (bool simple_p, basic_block bb)
5618 rtx_jump_insn *jump = emit_jump_insn_after (gen_return_pattern (simple_p),
5619 BB_END (bb));
5620 rtx pat = PATTERN (jump);
5621 if (GET_CODE (pat) == PARALLEL)
5622 pat = XVECEXP (pat, 0, 0);
5623 gcc_assert (ANY_RETURN_P (pat));
5624 JUMP_LABEL (jump) = pat;
5627 /* Set JUMP_LABEL for a return insn. */
5629 void
5630 set_return_jump_label (rtx_insn *returnjump)
5632 rtx pat = PATTERN (returnjump);
5633 if (GET_CODE (pat) == PARALLEL)
5634 pat = XVECEXP (pat, 0, 0);
5635 if (ANY_RETURN_P (pat))
5636 JUMP_LABEL (returnjump) = pat;
5637 else
5638 JUMP_LABEL (returnjump) = ret_rtx;
5641 /* Return true if there are any active insns between HEAD and TAIL. */
5642 bool
5643 active_insn_between (rtx_insn *head, rtx_insn *tail)
5645 while (tail)
5647 if (active_insn_p (tail))
5648 return true;
5649 if (tail == head)
5650 return false;
5651 tail = PREV_INSN (tail);
5653 return false;
5656 /* LAST_BB is a block that exits, and empty of active instructions.
5657 Examine its predecessors for jumps that can be converted to
5658 (conditional) returns. */
5659 vec<edge>
5660 convert_jumps_to_returns (basic_block last_bb, bool simple_p,
5661 vec<edge> unconverted ATTRIBUTE_UNUSED)
5663 int i;
5664 basic_block bb;
5665 edge_iterator ei;
5666 edge e;
5667 auto_vec<basic_block> src_bbs (EDGE_COUNT (last_bb->preds));
5669 FOR_EACH_EDGE (e, ei, last_bb->preds)
5670 if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
5671 src_bbs.quick_push (e->src);
5673 rtx_insn *label = BB_HEAD (last_bb);
5675 FOR_EACH_VEC_ELT (src_bbs, i, bb)
5677 rtx_insn *jump = BB_END (bb);
5679 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5680 continue;
5682 e = find_edge (bb, last_bb);
5684 /* If we have an unconditional jump, we can replace that
5685 with a simple return instruction. */
5686 if (simplejump_p (jump))
5688 /* The use of the return register might be present in the exit
5689 fallthru block. Either:
5690 - removing the use is safe, and we should remove the use in
5691 the exit fallthru block, or
5692 - removing the use is not safe, and we should add it here.
5693 For now, we conservatively choose the latter. Either of the
5694 2 helps in crossjumping. */
5695 emit_use_return_register_into_block (bb);
5697 emit_return_into_block (simple_p, bb);
5698 delete_insn (jump);
5701 /* If we have a conditional jump branching to the last
5702 block, we can try to replace that with a conditional
5703 return instruction. */
5704 else if (condjump_p (jump))
5706 rtx dest;
5708 if (simple_p)
5709 dest = simple_return_rtx;
5710 else
5711 dest = ret_rtx;
5712 if (!redirect_jump (as_a <rtx_jump_insn *> (jump), dest, 0))
5714 if (targetm.have_simple_return () && simple_p)
5716 if (dump_file)
5717 fprintf (dump_file,
5718 "Failed to redirect bb %d branch.\n", bb->index);
5719 unconverted.safe_push (e);
5721 continue;
5724 /* See comment in simplejump_p case above. */
5725 emit_use_return_register_into_block (bb);
5727 /* If this block has only one successor, it both jumps
5728 and falls through to the fallthru block, so we can't
5729 delete the edge. */
5730 if (single_succ_p (bb))
5731 continue;
5733 else
5735 if (targetm.have_simple_return () && simple_p)
5737 if (dump_file)
5738 fprintf (dump_file,
5739 "Failed to redirect bb %d branch.\n", bb->index);
5740 unconverted.safe_push (e);
5742 continue;
5745 /* Fix up the CFG for the successful change we just made. */
5746 redirect_edge_succ (e, EXIT_BLOCK_PTR_FOR_FN (cfun));
5747 e->flags &= ~EDGE_CROSSING;
5749 src_bbs.release ();
5750 return unconverted;
5753 /* Emit a return insn for the exit fallthru block. */
5754 basic_block
5755 emit_return_for_exit (edge exit_fallthru_edge, bool simple_p)
5757 basic_block last_bb = exit_fallthru_edge->src;
5759 if (JUMP_P (BB_END (last_bb)))
5761 last_bb = split_edge (exit_fallthru_edge);
5762 exit_fallthru_edge = single_succ_edge (last_bb);
5764 emit_barrier_after (BB_END (last_bb));
5765 emit_return_into_block (simple_p, last_bb);
5766 exit_fallthru_edge->flags &= ~EDGE_FALLTHRU;
5767 return last_bb;
5771 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5772 this into place with notes indicating where the prologue ends and where
5773 the epilogue begins. Update the basic block information when possible.
5775 Notes on epilogue placement:
5776 There are several kinds of edges to the exit block:
5777 * a single fallthru edge from LAST_BB
5778 * possibly, edges from blocks containing sibcalls
5779 * possibly, fake edges from infinite loops
5781 The epilogue is always emitted on the fallthru edge from the last basic
5782 block in the function, LAST_BB, into the exit block.
5784 If LAST_BB is empty except for a label, it is the target of every
5785 other basic block in the function that ends in a return. If a
5786 target has a return or simple_return pattern (possibly with
5787 conditional variants), these basic blocks can be changed so that a
5788 return insn is emitted into them, and their target is adjusted to
5789 the real exit block.
5791 Notes on shrink wrapping: We implement a fairly conservative
5792 version of shrink-wrapping rather than the textbook one. We only
5793 generate a single prologue and a single epilogue. This is
5794 sufficient to catch a number of interesting cases involving early
5795 exits.
5797 First, we identify the blocks that require the prologue to occur before
5798 them. These are the ones that modify a call-saved register, or reference
5799 any of the stack or frame pointer registers. To simplify things, we then
5800 mark everything reachable from these blocks as also requiring a prologue.
5801 This takes care of loops automatically, and avoids the need to examine
5802 whether MEMs reference the frame, since it is sufficient to check for
5803 occurrences of the stack or frame pointer.
5805 We then compute the set of blocks for which the need for a prologue
5806 is anticipatable (borrowing terminology from the shrink-wrapping
5807 description in Muchnick's book). These are the blocks which either
5808 require a prologue themselves, or those that have only successors
5809 where the prologue is anticipatable. The prologue needs to be
5810 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5811 is not. For the moment, we ensure that only one such edge exists.
5813 The epilogue is placed as described above, but we make a
5814 distinction between inserting return and simple_return patterns
5815 when modifying other blocks that end in a return. Blocks that end
5816 in a sibcall omit the sibcall_epilogue if the block is not in
5817 ANTIC. */
5819 void
5820 thread_prologue_and_epilogue_insns (void)
5822 bool inserted;
5823 vec<edge> unconverted_simple_returns = vNULL;
5824 bitmap_head bb_flags;
5825 rtx_insn *returnjump;
5826 rtx_insn *epilogue_end ATTRIBUTE_UNUSED;
5827 rtx_insn *prologue_seq ATTRIBUTE_UNUSED, *split_prologue_seq ATTRIBUTE_UNUSED;
5828 edge e, entry_edge, orig_entry_edge, exit_fallthru_edge;
5829 edge_iterator ei;
5831 df_analyze ();
5833 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5835 inserted = false;
5836 epilogue_end = NULL;
5837 returnjump = NULL;
5839 /* Can't deal with multiple successors of the entry block at the
5840 moment. Function should always have at least one entry
5841 point. */
5842 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun)));
5843 entry_edge = single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun));
5844 orig_entry_edge = entry_edge;
5846 split_prologue_seq = NULL;
5847 if (flag_split_stack
5848 && (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun->decl))
5849 == NULL))
5851 #ifndef HAVE_split_stack_prologue
5852 gcc_unreachable ();
5853 #else
5854 gcc_assert (HAVE_split_stack_prologue);
5856 start_sequence ();
5857 emit_insn (gen_split_stack_prologue ());
5858 split_prologue_seq = get_insns ();
5859 end_sequence ();
5861 record_insns (split_prologue_seq, NULL, &prologue_insn_hash);
5862 set_insn_locations (split_prologue_seq, prologue_location);
5863 #endif
5866 prologue_seq = NULL;
5867 if (targetm.have_prologue ())
5869 start_sequence ();
5870 rtx_insn *seq = targetm.gen_prologue ();
5871 emit_insn (seq);
5873 /* Insert an explicit USE for the frame pointer
5874 if the profiling is on and the frame pointer is required. */
5875 if (crtl->profile && frame_pointer_needed)
5876 emit_use (hard_frame_pointer_rtx);
5878 /* Retain a map of the prologue insns. */
5879 record_insns (seq, NULL, &prologue_insn_hash);
5880 emit_note (NOTE_INSN_PROLOGUE_END);
5882 /* Ensure that instructions are not moved into the prologue when
5883 profiling is on. The call to the profiling routine can be
5884 emitted within the live range of a call-clobbered register. */
5885 if (!targetm.profile_before_prologue () && crtl->profile)
5886 emit_insn (gen_blockage ());
5888 prologue_seq = get_insns ();
5889 end_sequence ();
5890 set_insn_locations (prologue_seq, prologue_location);
5893 bitmap_initialize (&bb_flags, &bitmap_default_obstack);
5895 /* Try to perform a kind of shrink-wrapping, making sure the
5896 prologue/epilogue is emitted only around those parts of the
5897 function that require it. */
5899 try_shrink_wrapping (&entry_edge, orig_entry_edge, &bb_flags, prologue_seq);
5901 if (split_prologue_seq != NULL_RTX)
5903 insert_insn_on_edge (split_prologue_seq, orig_entry_edge);
5904 inserted = true;
5906 if (prologue_seq != NULL_RTX)
5908 insert_insn_on_edge (prologue_seq, entry_edge);
5909 inserted = true;
5912 /* If the exit block has no non-fake predecessors, we don't need
5913 an epilogue. */
5914 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5915 if ((e->flags & EDGE_FAKE) == 0)
5916 break;
5917 if (e == NULL)
5918 goto epilogue_done;
5920 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun));
5922 exit_fallthru_edge = find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds);
5924 if (targetm.have_simple_return () && entry_edge != orig_entry_edge)
5925 exit_fallthru_edge
5926 = get_unconverted_simple_return (exit_fallthru_edge, bb_flags,
5927 &unconverted_simple_returns,
5928 &returnjump);
5929 if (targetm.have_return ())
5931 if (exit_fallthru_edge == NULL)
5932 goto epilogue_done;
5934 if (optimize)
5936 basic_block last_bb = exit_fallthru_edge->src;
5938 if (LABEL_P (BB_HEAD (last_bb))
5939 && !active_insn_between (BB_HEAD (last_bb), BB_END (last_bb)))
5940 convert_jumps_to_returns (last_bb, false, vNULL);
5942 if (EDGE_COUNT (last_bb->preds) != 0
5943 && single_succ_p (last_bb))
5945 last_bb = emit_return_for_exit (exit_fallthru_edge, false);
5946 epilogue_end = returnjump = BB_END (last_bb);
5948 /* Emitting the return may add a basic block.
5949 Fix bb_flags for the added block. */
5950 if (targetm.have_simple_return ()
5951 && last_bb != exit_fallthru_edge->src)
5952 bitmap_set_bit (&bb_flags, last_bb->index);
5954 goto epilogue_done;
5959 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5960 this marker for the splits of EH_RETURN patterns, and nothing else
5961 uses the flag in the meantime. */
5962 epilogue_completed = 1;
5964 #ifdef HAVE_eh_return
5965 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5966 some targets, these get split to a special version of the epilogue
5967 code. In order to be able to properly annotate these with unwind
5968 info, try to split them now. If we get a valid split, drop an
5969 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5970 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5972 rtx_insn *prev, *last, *trial;
5974 if (e->flags & EDGE_FALLTHRU)
5975 continue;
5976 last = BB_END (e->src);
5977 if (!eh_returnjump_p (last))
5978 continue;
5980 prev = PREV_INSN (last);
5981 trial = try_split (PATTERN (last), last, 1);
5982 if (trial == last)
5983 continue;
5985 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5986 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5988 #endif
5990 /* If nothing falls through into the exit block, we don't need an
5991 epilogue. */
5993 if (exit_fallthru_edge == NULL)
5994 goto epilogue_done;
5996 if (targetm.have_epilogue ())
5998 start_sequence ();
5999 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
6000 rtx_insn *seq = targetm.gen_epilogue ();
6001 if (seq)
6002 emit_jump_insn (seq);
6004 /* Retain a map of the epilogue insns. */
6005 record_insns (seq, NULL, &epilogue_insn_hash);
6006 set_insn_locations (seq, epilogue_location);
6008 seq = get_insns ();
6009 returnjump = get_last_insn ();
6010 end_sequence ();
6012 insert_insn_on_edge (seq, exit_fallthru_edge);
6013 inserted = true;
6015 if (JUMP_P (returnjump))
6016 set_return_jump_label (returnjump);
6018 else
6020 basic_block cur_bb;
6022 if (! next_active_insn (BB_END (exit_fallthru_edge->src)))
6023 goto epilogue_done;
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 FOR_EACH_BB_FN (cur_bb, cfun)
6033 if (cur_bb->index >= NUM_FIXED_BLOCKS
6034 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
6035 cur_bb->aux = cur_bb->next_bb;
6036 cfg_layout_finalize ();
6039 epilogue_done:
6041 default_rtl_profile ();
6043 if (inserted)
6045 sbitmap blocks;
6047 commit_edge_insertions ();
6049 /* Look for basic blocks within the prologue insns. */
6050 blocks = sbitmap_alloc (last_basic_block_for_fn (cfun));
6051 bitmap_clear (blocks);
6052 bitmap_set_bit (blocks, entry_edge->dest->index);
6053 bitmap_set_bit (blocks, orig_entry_edge->dest->index);
6054 find_many_sub_basic_blocks (blocks);
6055 sbitmap_free (blocks);
6057 /* The epilogue insns we inserted may cause the exit edge to no longer
6058 be fallthru. */
6059 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6061 if (((e->flags & EDGE_FALLTHRU) != 0)
6062 && returnjump_p (BB_END (e->src)))
6063 e->flags &= ~EDGE_FALLTHRU;
6067 if (targetm.have_simple_return ())
6068 convert_to_simple_return (entry_edge, orig_entry_edge, bb_flags,
6069 returnjump, unconverted_simple_returns);
6071 /* Emit sibling epilogues before any sibling call sites. */
6072 for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun)->preds); (e =
6073 ei_safe_edge (ei));
6076 basic_block bb = e->src;
6077 rtx_insn *insn = BB_END (bb);
6079 if (!CALL_P (insn)
6080 || ! SIBLING_CALL_P (insn)
6081 || (targetm.have_simple_return ()
6082 && entry_edge != orig_entry_edge
6083 && !bitmap_bit_p (&bb_flags, bb->index)))
6085 ei_next (&ei);
6086 continue;
6089 if (rtx_insn *ep_seq = targetm.gen_sibcall_epilogue ())
6091 start_sequence ();
6092 emit_note (NOTE_INSN_EPILOGUE_BEG);
6093 emit_insn (ep_seq);
6094 rtx_insn *seq = get_insns ();
6095 end_sequence ();
6097 /* Retain a map of the epilogue insns. Used in life analysis to
6098 avoid getting rid of sibcall epilogue insns. Do this before we
6099 actually emit the sequence. */
6100 record_insns (seq, NULL, &epilogue_insn_hash);
6101 set_insn_locations (seq, epilogue_location);
6103 emit_insn_before (seq, insn);
6105 ei_next (&ei);
6108 if (epilogue_end)
6110 rtx_insn *insn, *next;
6112 /* Similarly, move any line notes that appear after the epilogue.
6113 There is no need, however, to be quite so anal about the existence
6114 of such a note. Also possibly move
6115 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6116 info generation. */
6117 for (insn = epilogue_end; insn; insn = next)
6119 next = NEXT_INSN (insn);
6120 if (NOTE_P (insn)
6121 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
6122 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
6126 bitmap_clear (&bb_flags);
6128 /* Threading the prologue and epilogue changes the artificial refs
6129 in the entry and exit blocks. */
6130 epilogue_completed = 1;
6131 df_update_entry_exit_and_calls ();
6134 /* Reposition the prologue-end and epilogue-begin notes after
6135 instruction scheduling. */
6137 void
6138 reposition_prologue_and_epilogue_notes (void)
6140 if (!targetm.have_prologue ()
6141 && !targetm.have_epilogue ()
6142 && !targetm.have_sibcall_epilogue ())
6143 return;
6145 /* Since the hash table is created on demand, the fact that it is
6146 non-null is a signal that it is non-empty. */
6147 if (prologue_insn_hash != NULL)
6149 size_t len = prologue_insn_hash->elements ();
6150 rtx_insn *insn, *last = NULL, *note = NULL;
6152 /* Scan from the beginning until we reach the last prologue insn. */
6153 /* ??? While we do have the CFG intact, there are two problems:
6154 (1) The prologue can contain loops (typically probing the stack),
6155 which means that the end of the prologue isn't in the first bb.
6156 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6157 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
6159 if (NOTE_P (insn))
6161 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
6162 note = insn;
6164 else if (contains (insn, prologue_insn_hash))
6166 last = insn;
6167 if (--len == 0)
6168 break;
6172 if (last)
6174 if (note == NULL)
6176 /* Scan forward looking for the PROLOGUE_END note. It should
6177 be right at the beginning of the block, possibly with other
6178 insn notes that got moved there. */
6179 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
6181 if (NOTE_P (note)
6182 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
6183 break;
6187 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6188 if (LABEL_P (last))
6189 last = NEXT_INSN (last);
6190 reorder_insns (note, note, last);
6194 if (epilogue_insn_hash != NULL)
6196 edge_iterator ei;
6197 edge e;
6199 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
6201 rtx_insn *insn, *first = NULL, *note = NULL;
6202 basic_block bb = e->src;
6204 /* Scan from the beginning until we reach the first epilogue insn. */
6205 FOR_BB_INSNS (bb, insn)
6207 if (NOTE_P (insn))
6209 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
6211 note = insn;
6212 if (first != NULL)
6213 break;
6216 else if (first == NULL && contains (insn, epilogue_insn_hash))
6218 first = insn;
6219 if (note != NULL)
6220 break;
6224 if (note)
6226 /* If the function has a single basic block, and no real
6227 epilogue insns (e.g. sibcall with no cleanup), the
6228 epilogue note can get scheduled before the prologue
6229 note. If we have frame related prologue insns, having
6230 them scanned during the epilogue will result in a crash.
6231 In this case re-order the epilogue note to just before
6232 the last insn in the block. */
6233 if (first == NULL)
6234 first = BB_END (bb);
6236 if (PREV_INSN (first) != note)
6237 reorder_insns (note, note, PREV_INSN (first));
6243 /* Returns the name of function declared by FNDECL. */
6244 const char *
6245 fndecl_name (tree fndecl)
6247 if (fndecl == NULL)
6248 return "(nofn)";
6249 return lang_hooks.decl_printable_name (fndecl, 2);
6252 /* Returns the name of function FN. */
6253 const char *
6254 function_name (struct function *fn)
6256 tree fndecl = (fn == NULL) ? NULL : fn->decl;
6257 return fndecl_name (fndecl);
6260 /* Returns the name of the current function. */
6261 const char *
6262 current_function_name (void)
6264 return function_name (cfun);
6268 static unsigned int
6269 rest_of_handle_check_leaf_regs (void)
6271 #ifdef LEAF_REGISTERS
6272 crtl->uses_only_leaf_regs
6273 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
6274 #endif
6275 return 0;
6278 /* Insert a TYPE into the used types hash table of CFUN. */
6280 static void
6281 used_types_insert_helper (tree type, struct function *func)
6283 if (type != NULL && func != NULL)
6285 if (func->used_types_hash == NULL)
6286 func->used_types_hash = hash_set<tree>::create_ggc (37);
6288 func->used_types_hash->add (type);
6292 /* Given a type, insert it into the used hash table in cfun. */
6293 void
6294 used_types_insert (tree t)
6296 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
6297 if (TYPE_NAME (t))
6298 break;
6299 else
6300 t = TREE_TYPE (t);
6301 if (TREE_CODE (t) == ERROR_MARK)
6302 return;
6303 if (TYPE_NAME (t) == NULL_TREE
6304 || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
6305 t = TYPE_MAIN_VARIANT (t);
6306 if (debug_info_level > DINFO_LEVEL_NONE)
6308 if (cfun)
6309 used_types_insert_helper (t, cfun);
6310 else
6312 /* So this might be a type referenced by a global variable.
6313 Record that type so that we can later decide to emit its
6314 debug information. */
6315 vec_safe_push (types_used_by_cur_var_decl, t);
6320 /* Helper to Hash a struct types_used_by_vars_entry. */
6322 static hashval_t
6323 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
6325 gcc_assert (entry && entry->var_decl && entry->type);
6327 return iterative_hash_object (entry->type,
6328 iterative_hash_object (entry->var_decl, 0));
6331 /* Hash function of the types_used_by_vars_entry hash table. */
6333 hashval_t
6334 used_type_hasher::hash (types_used_by_vars_entry *entry)
6336 return hash_types_used_by_vars_entry (entry);
6339 /*Equality function of the types_used_by_vars_entry hash table. */
6341 bool
6342 used_type_hasher::equal (types_used_by_vars_entry *e1,
6343 types_used_by_vars_entry *e2)
6345 return (e1->var_decl == e2->var_decl && e1->type == e2->type);
6348 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6350 void
6351 types_used_by_var_decl_insert (tree type, tree var_decl)
6353 if (type != NULL && var_decl != NULL)
6355 types_used_by_vars_entry **slot;
6356 struct types_used_by_vars_entry e;
6357 e.var_decl = var_decl;
6358 e.type = type;
6359 if (types_used_by_vars_hash == NULL)
6360 types_used_by_vars_hash
6361 = hash_table<used_type_hasher>::create_ggc (37);
6363 slot = types_used_by_vars_hash->find_slot (&e, INSERT);
6364 if (*slot == NULL)
6366 struct types_used_by_vars_entry *entry;
6367 entry = ggc_alloc<types_used_by_vars_entry> ();
6368 entry->type = type;
6369 entry->var_decl = var_decl;
6370 *slot = entry;
6375 namespace {
6377 const pass_data pass_data_leaf_regs =
6379 RTL_PASS, /* type */
6380 "*leaf_regs", /* name */
6381 OPTGROUP_NONE, /* optinfo_flags */
6382 TV_NONE, /* tv_id */
6383 0, /* properties_required */
6384 0, /* properties_provided */
6385 0, /* properties_destroyed */
6386 0, /* todo_flags_start */
6387 0, /* todo_flags_finish */
6390 class pass_leaf_regs : public rtl_opt_pass
6392 public:
6393 pass_leaf_regs (gcc::context *ctxt)
6394 : rtl_opt_pass (pass_data_leaf_regs, ctxt)
6397 /* opt_pass methods: */
6398 virtual unsigned int execute (function *)
6400 return rest_of_handle_check_leaf_regs ();
6403 }; // class pass_leaf_regs
6405 } // anon namespace
6407 rtl_opt_pass *
6408 make_pass_leaf_regs (gcc::context *ctxt)
6410 return new pass_leaf_regs (ctxt);
6413 static unsigned int
6414 rest_of_handle_thread_prologue_and_epilogue (void)
6416 if (optimize)
6417 cleanup_cfg (CLEANUP_EXPENSIVE);
6419 /* On some machines, the prologue and epilogue code, or parts thereof,
6420 can be represented as RTL. Doing so lets us schedule insns between
6421 it and the rest of the code and also allows delayed branch
6422 scheduling to operate in the epilogue. */
6423 thread_prologue_and_epilogue_insns ();
6425 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6426 see PR57320. */
6427 cleanup_cfg (0);
6429 /* The stack usage info is finalized during prologue expansion. */
6430 if (flag_stack_usage_info)
6431 output_stack_usage ();
6433 return 0;
6436 namespace {
6438 const pass_data pass_data_thread_prologue_and_epilogue =
6440 RTL_PASS, /* type */
6441 "pro_and_epilogue", /* name */
6442 OPTGROUP_NONE, /* optinfo_flags */
6443 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
6444 0, /* properties_required */
6445 0, /* properties_provided */
6446 0, /* properties_destroyed */
6447 0, /* todo_flags_start */
6448 ( TODO_df_verify | TODO_df_finish ), /* todo_flags_finish */
6451 class pass_thread_prologue_and_epilogue : public rtl_opt_pass
6453 public:
6454 pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6455 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue, ctxt)
6458 /* opt_pass methods: */
6459 virtual unsigned int execute (function *)
6461 return rest_of_handle_thread_prologue_and_epilogue ();
6464 }; // class pass_thread_prologue_and_epilogue
6466 } // anon namespace
6468 rtl_opt_pass *
6469 make_pass_thread_prologue_and_epilogue (gcc::context *ctxt)
6471 return new pass_thread_prologue_and_epilogue (ctxt);
6475 /* This mini-pass fixes fall-out from SSA in asm statements that have
6476 in-out constraints. Say you start with
6478 orig = inout;
6479 asm ("": "+mr" (inout));
6480 use (orig);
6482 which is transformed very early to use explicit output and match operands:
6484 orig = inout;
6485 asm ("": "=mr" (inout) : "0" (inout));
6486 use (orig);
6488 Or, after SSA and copyprop,
6490 asm ("": "=mr" (inout_2) : "0" (inout_1));
6491 use (inout_1);
6493 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6494 they represent two separate values, so they will get different pseudo
6495 registers during expansion. Then, since the two operands need to match
6496 per the constraints, but use different pseudo registers, reload can
6497 only register a reload for these operands. But reloads can only be
6498 satisfied by hardregs, not by memory, so we need a register for this
6499 reload, just because we are presented with non-matching operands.
6500 So, even though we allow memory for this operand, no memory can be
6501 used for it, just because the two operands don't match. This can
6502 cause reload failures on register-starved targets.
6504 So it's a symptom of reload not being able to use memory for reloads
6505 or, alternatively it's also a symptom of both operands not coming into
6506 reload as matching (in which case the pseudo could go to memory just
6507 fine, as the alternative allows it, and no reload would be necessary).
6508 We fix the latter problem here, by transforming
6510 asm ("": "=mr" (inout_2) : "0" (inout_1));
6512 back to
6514 inout_2 = inout_1;
6515 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6517 static void
6518 match_asm_constraints_1 (rtx_insn *insn, rtx *p_sets, int noutputs)
6520 int i;
6521 bool changed = false;
6522 rtx op = SET_SRC (p_sets[0]);
6523 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
6524 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
6525 bool *output_matched = XALLOCAVEC (bool, noutputs);
6527 memset (output_matched, 0, noutputs * sizeof (bool));
6528 for (i = 0; i < ninputs; i++)
6530 rtx input, output;
6531 rtx_insn *insns;
6532 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
6533 char *end;
6534 int match, j;
6536 if (*constraint == '%')
6537 constraint++;
6539 match = strtoul (constraint, &end, 10);
6540 if (end == constraint)
6541 continue;
6543 gcc_assert (match < noutputs);
6544 output = SET_DEST (p_sets[match]);
6545 input = RTVEC_ELT (inputs, i);
6546 /* Only do the transformation for pseudos. */
6547 if (! REG_P (output)
6548 || rtx_equal_p (output, input)
6549 || (GET_MODE (input) != VOIDmode
6550 && GET_MODE (input) != GET_MODE (output)))
6551 continue;
6553 /* We can't do anything if the output is also used as input,
6554 as we're going to overwrite it. */
6555 for (j = 0; j < ninputs; j++)
6556 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
6557 break;
6558 if (j != ninputs)
6559 continue;
6561 /* Avoid changing the same input several times. For
6562 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6563 only change in once (to out1), rather than changing it
6564 first to out1 and afterwards to out2. */
6565 if (i > 0)
6567 for (j = 0; j < noutputs; j++)
6568 if (output_matched[j] && input == SET_DEST (p_sets[j]))
6569 break;
6570 if (j != noutputs)
6571 continue;
6573 output_matched[match] = true;
6575 start_sequence ();
6576 emit_move_insn (output, input);
6577 insns = get_insns ();
6578 end_sequence ();
6579 emit_insn_before (insns, insn);
6581 /* Now replace all mentions of the input with output. We can't
6582 just replace the occurrence in inputs[i], as the register might
6583 also be used in some other input (or even in an address of an
6584 output), which would mean possibly increasing the number of
6585 inputs by one (namely 'output' in addition), which might pose
6586 a too complicated problem for reload to solve. E.g. this situation:
6588 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6590 Here 'input' is used in two occurrences as input (once for the
6591 input operand, once for the address in the second output operand).
6592 If we would replace only the occurrence of the input operand (to
6593 make the matching) we would be left with this:
6595 output = input
6596 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6598 Now we suddenly have two different input values (containing the same
6599 value, but different pseudos) where we formerly had only one.
6600 With more complicated asms this might lead to reload failures
6601 which wouldn't have happen without this pass. So, iterate over
6602 all operands and replace all occurrences of the register used. */
6603 for (j = 0; j < noutputs; j++)
6604 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
6605 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
6606 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
6607 input, output);
6608 for (j = 0; j < ninputs; j++)
6609 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
6610 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
6611 input, output);
6613 changed = true;
6616 if (changed)
6617 df_insn_rescan (insn);
6620 /* Add the decl D to the local_decls list of FUN. */
6622 void
6623 add_local_decl (struct function *fun, tree d)
6625 gcc_assert (TREE_CODE (d) == VAR_DECL);
6626 vec_safe_push (fun->local_decls, d);
6629 namespace {
6631 const pass_data pass_data_match_asm_constraints =
6633 RTL_PASS, /* type */
6634 "asmcons", /* name */
6635 OPTGROUP_NONE, /* optinfo_flags */
6636 TV_NONE, /* tv_id */
6637 0, /* properties_required */
6638 0, /* properties_provided */
6639 0, /* properties_destroyed */
6640 0, /* todo_flags_start */
6641 0, /* todo_flags_finish */
6644 class pass_match_asm_constraints : public rtl_opt_pass
6646 public:
6647 pass_match_asm_constraints (gcc::context *ctxt)
6648 : rtl_opt_pass (pass_data_match_asm_constraints, ctxt)
6651 /* opt_pass methods: */
6652 virtual unsigned int execute (function *);
6654 }; // class pass_match_asm_constraints
6656 unsigned
6657 pass_match_asm_constraints::execute (function *fun)
6659 basic_block bb;
6660 rtx_insn *insn;
6661 rtx pat, *p_sets;
6662 int noutputs;
6664 if (!crtl->has_asm_statement)
6665 return 0;
6667 df_set_flags (DF_DEFER_INSN_RESCAN);
6668 FOR_EACH_BB_FN (bb, fun)
6670 FOR_BB_INSNS (bb, insn)
6672 if (!INSN_P (insn))
6673 continue;
6675 pat = PATTERN (insn);
6676 if (GET_CODE (pat) == PARALLEL)
6677 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
6678 else if (GET_CODE (pat) == SET)
6679 p_sets = &PATTERN (insn), noutputs = 1;
6680 else
6681 continue;
6683 if (GET_CODE (*p_sets) == SET
6684 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
6685 match_asm_constraints_1 (insn, p_sets, noutputs);
6689 return TODO_df_finish;
6692 } // anon namespace
6694 rtl_opt_pass *
6695 make_pass_match_asm_constraints (gcc::context *ctxt)
6697 return new pass_match_asm_constraints (ctxt);
6701 #include "gt-function.h"