re PR testsuite/40567 (Revision 149002 caused many failures)
[official-gcc.git] / gcc / function.c
bloba0c45de2a1bef71fa1472d52790aae7515cd52ee
1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
36 #include "config.h"
37 #include "system.h"
38 #include "coretypes.h"
39 #include "tm.h"
40 #include "rtl.h"
41 #include "tree.h"
42 #include "flags.h"
43 #include "except.h"
44 #include "function.h"
45 #include "expr.h"
46 #include "optabs.h"
47 #include "libfuncs.h"
48 #include "regs.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
51 #include "recog.h"
52 #include "output.h"
53 #include "basic-block.h"
54 #include "toplev.h"
55 #include "hashtab.h"
56 #include "ggc.h"
57 #include "tm_p.h"
58 #include "integrate.h"
59 #include "langhooks.h"
60 #include "target.h"
61 #include "cfglayout.h"
62 #include "gimple.h"
63 #include "tree-pass.h"
64 #include "predict.h"
65 #include "df.h"
66 #include "timevar.h"
67 #include "vecprim.h"
69 /* So we can assign to cfun in this file. */
70 #undef cfun
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
74 #endif
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
82 #ifndef NAME__MAIN
83 #define NAME__MAIN "__main"
84 #endif
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
92 alignment. */
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
98 compiler passes. */
99 int current_function_is_leaf;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function * (*init_machine_status) (void);
124 /* The currently compiled function. */
125 struct function *cfun = 0;
127 /* These hashes record the prologue and epilogue insns. */
128 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
129 htab_t prologue_insn_hash;
130 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
131 htab_t epilogue_insn_hash;
133 /* Forward declarations. */
135 static struct temp_slot *find_temp_slot_from_address (rtx);
136 static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
137 static void pad_below (struct args_size *, enum machine_mode, tree);
138 static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
139 static int all_blocks (tree, tree *);
140 static tree *get_block_vector (tree, int *);
141 extern tree debug_find_var_in_block_tree (tree, tree);
142 /* We always define `record_insns' even if it's not used so that we
143 can always export `prologue_epilogue_contains'. */
144 static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
145 static bool contains (const_rtx, htab_t);
146 #ifdef HAVE_return
147 static void emit_return_into_block (basic_block);
148 #endif
149 static void prepare_function_start (void);
150 static void do_clobber_return_reg (rtx, void *);
151 static void do_use_return_reg (rtx, void *);
152 static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
154 /* Stack of nested functions. */
155 /* Keep track of the cfun stack. */
157 typedef struct function *function_p;
159 DEF_VEC_P(function_p);
160 DEF_VEC_ALLOC_P(function_p,heap);
161 static VEC(function_p,heap) *function_context_stack;
163 /* Save the current context for compilation of a nested function.
164 This is called from language-specific code. */
166 void
167 push_function_context (void)
169 if (cfun == 0)
170 allocate_struct_function (NULL, false);
172 VEC_safe_push (function_p, heap, function_context_stack, cfun);
173 set_cfun (NULL);
176 /* Restore the last saved context, at the end of a nested function.
177 This function is called from language-specific code. */
179 void
180 pop_function_context (void)
182 struct function *p = VEC_pop (function_p, function_context_stack);
183 set_cfun (p);
184 current_function_decl = p->decl;
186 /* Reset variables that have known state during rtx generation. */
187 virtuals_instantiated = 0;
188 generating_concat_p = 1;
191 /* Clear out all parts of the state in F that can safely be discarded
192 after the function has been parsed, but not compiled, to let
193 garbage collection reclaim the memory. */
195 void
196 free_after_parsing (struct function *f)
198 f->language = 0;
201 /* Clear out all parts of the state in F that can safely be discarded
202 after the function has been compiled, to let garbage collection
203 reclaim the memory. */
205 void
206 free_after_compilation (struct function *f)
208 prologue_insn_hash = NULL;
209 epilogue_insn_hash = NULL;
211 if (crtl->emit.regno_pointer_align)
212 free (crtl->emit.regno_pointer_align);
214 memset (crtl, 0, sizeof (struct rtl_data));
215 f->eh = NULL;
216 f->machine = NULL;
217 f->cfg = NULL;
219 regno_reg_rtx = NULL;
220 insn_locators_free ();
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 ("%Jtotal size of local objects too large", func);
250 return TRUE;
253 return FALSE;
256 /* Return stack slot alignment in bits for TYPE and MODE. */
258 static unsigned int
259 get_stack_local_alignment (tree type, enum machine_mode mode)
261 unsigned int alignment;
263 if (mode == BLKmode)
264 alignment = BIGGEST_ALIGNMENT;
265 else
266 alignment = GET_MODE_ALIGNMENT (mode);
268 /* Allow the frond-end to (possibly) increase the alignment of this
269 stack slot. */
270 if (! type)
271 type = lang_hooks.types.type_for_mode (mode, 0);
273 return STACK_SLOT_ALIGNMENT (type, mode, alignment);
276 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
277 with machine mode MODE.
279 ALIGN controls the amount of alignment for the address of the slot:
280 0 means according to MODE,
281 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
282 -2 means use BITS_PER_UNIT,
283 positive specifies alignment boundary in bits.
285 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
287 We do not round to stack_boundary here. */
290 assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
291 int align,
292 bool reduce_alignment_ok ATTRIBUTE_UNUSED)
294 rtx x, addr;
295 int bigend_correction = 0;
296 unsigned int alignment, alignment_in_bits;
297 int frame_off, frame_alignment, frame_phase;
299 if (align == 0)
301 alignment = get_stack_local_alignment (NULL, mode);
302 alignment /= BITS_PER_UNIT;
304 else if (align == -1)
306 alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
307 size = CEIL_ROUND (size, alignment);
309 else if (align == -2)
310 alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
311 else
312 alignment = align / BITS_PER_UNIT;
314 alignment_in_bits = alignment * BITS_PER_UNIT;
316 if (FRAME_GROWS_DOWNWARD)
317 frame_offset -= size;
319 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
320 if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
322 alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
323 alignment = alignment_in_bits / BITS_PER_UNIT;
326 if (SUPPORTS_STACK_ALIGNMENT)
328 if (crtl->stack_alignment_estimated < alignment_in_bits)
330 if (!crtl->stack_realign_processed)
331 crtl->stack_alignment_estimated = alignment_in_bits;
332 else
334 /* If stack is realigned and stack alignment value
335 hasn't been finalized, it is OK not to increase
336 stack_alignment_estimated. The bigger alignment
337 requirement is recorded in stack_alignment_needed
338 below. */
339 gcc_assert (!crtl->stack_realign_finalized);
340 if (!crtl->stack_realign_needed)
342 /* It is OK to reduce the alignment as long as the
343 requested size is 0 or the estimated stack
344 alignment >= mode alignment. */
345 gcc_assert (reduce_alignment_ok
346 || size == 0
347 || (crtl->stack_alignment_estimated
348 >= GET_MODE_ALIGNMENT (mode)));
349 alignment_in_bits = crtl->stack_alignment_estimated;
350 alignment = alignment_in_bits / BITS_PER_UNIT;
356 if (crtl->stack_alignment_needed < alignment_in_bits)
357 crtl->stack_alignment_needed = alignment_in_bits;
358 if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
359 crtl->max_used_stack_slot_alignment = alignment_in_bits;
361 /* Calculate how many bytes the start of local variables is off from
362 stack alignment. */
363 frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
364 frame_off = STARTING_FRAME_OFFSET % frame_alignment;
365 frame_phase = frame_off ? frame_alignment - frame_off : 0;
367 /* Round the frame offset to the specified alignment. The default is
368 to always honor requests to align the stack but a port may choose to
369 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
370 if (STACK_ALIGNMENT_NEEDED
371 || mode != BLKmode
372 || size != 0)
374 /* We must be careful here, since FRAME_OFFSET might be negative and
375 division with a negative dividend isn't as well defined as we might
376 like. So we instead assume that ALIGNMENT is a power of two and
377 use logical operations which are unambiguous. */
378 if (FRAME_GROWS_DOWNWARD)
379 frame_offset
380 = (FLOOR_ROUND (frame_offset - frame_phase,
381 (unsigned HOST_WIDE_INT) alignment)
382 + frame_phase);
383 else
384 frame_offset
385 = (CEIL_ROUND (frame_offset - frame_phase,
386 (unsigned HOST_WIDE_INT) alignment)
387 + frame_phase);
390 /* On a big-endian machine, if we are allocating more space than we will use,
391 use the least significant bytes of those that are allocated. */
392 if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
393 bigend_correction = size - GET_MODE_SIZE (mode);
395 /* If we have already instantiated virtual registers, return the actual
396 address relative to the frame pointer. */
397 if (virtuals_instantiated)
398 addr = plus_constant (frame_pointer_rtx,
399 trunc_int_for_mode
400 (frame_offset + bigend_correction
401 + STARTING_FRAME_OFFSET, Pmode));
402 else
403 addr = plus_constant (virtual_stack_vars_rtx,
404 trunc_int_for_mode
405 (frame_offset + bigend_correction,
406 Pmode));
408 if (!FRAME_GROWS_DOWNWARD)
409 frame_offset += size;
411 x = gen_rtx_MEM (mode, addr);
412 set_mem_align (x, alignment_in_bits);
413 MEM_NOTRAP_P (x) = 1;
415 stack_slot_list
416 = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
418 if (frame_offset_overflow (frame_offset, current_function_decl))
419 frame_offset = 0;
421 return x;
424 /* Wrap up assign_stack_local_1 with last parameter as false. */
427 assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
429 return assign_stack_local_1 (mode, size, align, false);
433 /* In order to evaluate some expressions, such as function calls returning
434 structures in memory, we need to temporarily allocate stack locations.
435 We record each allocated temporary in the following structure.
437 Associated with each temporary slot is a nesting level. When we pop up
438 one level, all temporaries associated with the previous level are freed.
439 Normally, all temporaries are freed after the execution of the statement
440 in which they were created. However, if we are inside a ({...}) grouping,
441 the result may be in a temporary and hence must be preserved. If the
442 result could be in a temporary, we preserve it if we can determine which
443 one it is in. If we cannot determine which temporary may contain the
444 result, all temporaries are preserved. A temporary is preserved by
445 pretending it was allocated at the previous nesting level.
447 Automatic variables are also assigned temporary slots, at the nesting
448 level where they are defined. They are marked a "kept" so that
449 free_temp_slots will not free them. */
451 struct GTY(()) temp_slot {
452 /* Points to next temporary slot. */
453 struct temp_slot *next;
454 /* Points to previous temporary slot. */
455 struct temp_slot *prev;
456 /* The rtx to used to reference the slot. */
457 rtx slot;
458 /* The size, in units, of the slot. */
459 HOST_WIDE_INT size;
460 /* The type of the object in the slot, or zero if it doesn't correspond
461 to a type. We use this to determine whether a slot can be reused.
462 It can be reused if objects of the type of the new slot will always
463 conflict with objects of the type of the old slot. */
464 tree type;
465 /* The alignment (in bits) of the slot. */
466 unsigned int align;
467 /* Nonzero if this temporary is currently in use. */
468 char in_use;
469 /* Nonzero if this temporary has its address taken. */
470 char addr_taken;
471 /* Nesting level at which this slot is being used. */
472 int level;
473 /* Nonzero if this should survive a call to free_temp_slots. */
474 int keep;
475 /* The offset of the slot from the frame_pointer, including extra space
476 for alignment. This info is for combine_temp_slots. */
477 HOST_WIDE_INT base_offset;
478 /* The size of the slot, including extra space for alignment. This
479 info is for combine_temp_slots. */
480 HOST_WIDE_INT full_size;
483 /* A table of addresses that represent a stack slot. The table is a mapping
484 from address RTXen to a temp slot. */
485 static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
487 /* Entry for the above hash table. */
488 struct GTY(()) temp_slot_address_entry {
489 hashval_t hash;
490 rtx address;
491 struct temp_slot *temp_slot;
494 /* Removes temporary slot TEMP from LIST. */
496 static void
497 cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
499 if (temp->next)
500 temp->next->prev = temp->prev;
501 if (temp->prev)
502 temp->prev->next = temp->next;
503 else
504 *list = temp->next;
506 temp->prev = temp->next = NULL;
509 /* Inserts temporary slot TEMP to LIST. */
511 static void
512 insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
514 temp->next = *list;
515 if (*list)
516 (*list)->prev = temp;
517 temp->prev = NULL;
518 *list = temp;
521 /* Returns the list of used temp slots at LEVEL. */
523 static struct temp_slot **
524 temp_slots_at_level (int level)
526 if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
527 VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
529 return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
532 /* Returns the maximal temporary slot level. */
534 static int
535 max_slot_level (void)
537 if (!used_temp_slots)
538 return -1;
540 return VEC_length (temp_slot_p, used_temp_slots) - 1;
543 /* Moves temporary slot TEMP to LEVEL. */
545 static void
546 move_slot_to_level (struct temp_slot *temp, int level)
548 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
549 insert_slot_to_list (temp, temp_slots_at_level (level));
550 temp->level = level;
553 /* Make temporary slot TEMP available. */
555 static void
556 make_slot_available (struct temp_slot *temp)
558 cut_slot_from_list (temp, temp_slots_at_level (temp->level));
559 insert_slot_to_list (temp, &avail_temp_slots);
560 temp->in_use = 0;
561 temp->level = -1;
564 /* Compute the hash value for an address -> temp slot mapping.
565 The value is cached on the mapping entry. */
566 static hashval_t
567 temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
569 int do_not_record = 0;
570 return hash_rtx (t->address, GET_MODE (t->address),
571 &do_not_record, NULL, false);
574 /* Return the hash value for an address -> temp slot mapping. */
575 static hashval_t
576 temp_slot_address_hash (const void *p)
578 const struct temp_slot_address_entry *t;
579 t = (const struct temp_slot_address_entry *) p;
580 return t->hash;
583 /* Compare two address -> temp slot mapping entries. */
584 static int
585 temp_slot_address_eq (const void *p1, const void *p2)
587 const struct temp_slot_address_entry *t1, *t2;
588 t1 = (const struct temp_slot_address_entry *) p1;
589 t2 = (const struct temp_slot_address_entry *) p2;
590 return exp_equiv_p (t1->address, t2->address, 0, true);
593 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
594 static void
595 insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
597 void **slot;
598 struct temp_slot_address_entry *t = GGC_NEW (struct temp_slot_address_entry);
599 t->address = address;
600 t->temp_slot = temp_slot;
601 t->hash = temp_slot_address_compute_hash (t);
602 slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
603 *slot = t;
606 /* Remove an address -> temp slot mapping entry if the temp slot is
607 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
608 static int
609 remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
611 const struct temp_slot_address_entry *t;
612 t = (const struct temp_slot_address_entry *) *slot;
613 if (! t->temp_slot->in_use)
614 *slot = NULL;
615 return 1;
618 /* Remove all mappings of addresses to unused temp slots. */
619 static void
620 remove_unused_temp_slot_addresses (void)
622 htab_traverse (temp_slot_address_table,
623 remove_unused_temp_slot_addresses_1,
624 NULL);
627 /* Find the temp slot corresponding to the object at address X. */
629 static struct temp_slot *
630 find_temp_slot_from_address (rtx x)
632 struct temp_slot *p;
633 struct temp_slot_address_entry tmp, *t;
635 /* First try the easy way:
636 See if X exists in the address -> temp slot mapping. */
637 tmp.address = x;
638 tmp.temp_slot = NULL;
639 tmp.hash = temp_slot_address_compute_hash (&tmp);
640 t = (struct temp_slot_address_entry *)
641 htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
642 if (t)
643 return t->temp_slot;
645 /* If we have a sum involving a register, see if it points to a temp
646 slot. */
647 if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
648 && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
649 return p;
650 else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
651 && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
652 return p;
654 /* Last resort: Address is a virtual stack var address. */
655 if (GET_CODE (x) == PLUS
656 && XEXP (x, 0) == virtual_stack_vars_rtx
657 && CONST_INT_P (XEXP (x, 1)))
659 int i;
660 for (i = max_slot_level (); i >= 0; i--)
661 for (p = *temp_slots_at_level (i); p; p = p->next)
663 if (INTVAL (XEXP (x, 1)) >= p->base_offset
664 && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
665 return p;
669 return NULL;
672 /* Allocate a temporary stack slot and record it for possible later
673 reuse.
675 MODE is the machine mode to be given to the returned rtx.
677 SIZE is the size in units of the space required. We do no rounding here
678 since assign_stack_local will do any required rounding.
680 KEEP is 1 if this slot is to be retained after a call to
681 free_temp_slots. Automatic variables for a block are allocated
682 with this flag. KEEP values of 2 or 3 were needed respectively
683 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
684 or for SAVE_EXPRs, but they are now unused.
686 TYPE is the type that will be used for the stack slot. */
689 assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
690 int keep, tree type)
692 unsigned int align;
693 struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
694 rtx slot;
696 /* If SIZE is -1 it means that somebody tried to allocate a temporary
697 of a variable size. */
698 gcc_assert (size != -1);
700 /* These are now unused. */
701 gcc_assert (keep <= 1);
703 align = get_stack_local_alignment (type, mode);
705 /* Try to find an available, already-allocated temporary of the proper
706 mode which meets the size and alignment requirements. Choose the
707 smallest one with the closest alignment.
709 If assign_stack_temp is called outside of the tree->rtl expansion,
710 we cannot reuse the stack slots (that may still refer to
711 VIRTUAL_STACK_VARS_REGNUM). */
712 if (!virtuals_instantiated)
714 for (p = avail_temp_slots; p; p = p->next)
716 if (p->align >= align && p->size >= size
717 && GET_MODE (p->slot) == mode
718 && objects_must_conflict_p (p->type, type)
719 && (best_p == 0 || best_p->size > p->size
720 || (best_p->size == p->size && best_p->align > p->align)))
722 if (p->align == align && p->size == size)
724 selected = p;
725 cut_slot_from_list (selected, &avail_temp_slots);
726 best_p = 0;
727 break;
729 best_p = p;
734 /* Make our best, if any, the one to use. */
735 if (best_p)
737 selected = best_p;
738 cut_slot_from_list (selected, &avail_temp_slots);
740 /* If there are enough aligned bytes left over, make them into a new
741 temp_slot so that the extra bytes don't get wasted. Do this only
742 for BLKmode slots, so that we can be sure of the alignment. */
743 if (GET_MODE (best_p->slot) == BLKmode)
745 int alignment = best_p->align / BITS_PER_UNIT;
746 HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
748 if (best_p->size - rounded_size >= alignment)
750 p = GGC_NEW (struct temp_slot);
751 p->in_use = p->addr_taken = 0;
752 p->size = best_p->size - rounded_size;
753 p->base_offset = best_p->base_offset + rounded_size;
754 p->full_size = best_p->full_size - rounded_size;
755 p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
756 p->align = best_p->align;
757 p->type = best_p->type;
758 insert_slot_to_list (p, &avail_temp_slots);
760 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
761 stack_slot_list);
763 best_p->size = rounded_size;
764 best_p->full_size = rounded_size;
769 /* If we still didn't find one, make a new temporary. */
770 if (selected == 0)
772 HOST_WIDE_INT frame_offset_old = frame_offset;
774 p = GGC_NEW (struct temp_slot);
776 /* We are passing an explicit alignment request to assign_stack_local.
777 One side effect of that is assign_stack_local will not round SIZE
778 to ensure the frame offset remains suitably aligned.
780 So for requests which depended on the rounding of SIZE, we go ahead
781 and round it now. We also make sure ALIGNMENT is at least
782 BIGGEST_ALIGNMENT. */
783 gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
784 p->slot = assign_stack_local (mode,
785 (mode == BLKmode
786 ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
787 : size),
788 align);
790 p->align = align;
792 /* The following slot size computation is necessary because we don't
793 know the actual size of the temporary slot until assign_stack_local
794 has performed all the frame alignment and size rounding for the
795 requested temporary. Note that extra space added for alignment
796 can be either above or below this stack slot depending on which
797 way the frame grows. We include the extra space if and only if it
798 is above this slot. */
799 if (FRAME_GROWS_DOWNWARD)
800 p->size = frame_offset_old - frame_offset;
801 else
802 p->size = size;
804 /* Now define the fields used by combine_temp_slots. */
805 if (FRAME_GROWS_DOWNWARD)
807 p->base_offset = frame_offset;
808 p->full_size = frame_offset_old - frame_offset;
810 else
812 p->base_offset = frame_offset_old;
813 p->full_size = frame_offset - frame_offset_old;
816 selected = p;
819 p = selected;
820 p->in_use = 1;
821 p->addr_taken = 0;
822 p->type = type;
823 p->level = temp_slot_level;
824 p->keep = keep;
826 pp = temp_slots_at_level (p->level);
827 insert_slot_to_list (p, pp);
828 insert_temp_slot_address (XEXP (p->slot, 0), p);
830 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
831 slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
832 stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
834 /* If we know the alias set for the memory that will be used, use
835 it. If there's no TYPE, then we don't know anything about the
836 alias set for the memory. */
837 set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
838 set_mem_align (slot, align);
840 /* If a type is specified, set the relevant flags. */
841 if (type != 0)
843 MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
844 MEM_SET_IN_STRUCT_P (slot, (AGGREGATE_TYPE_P (type)
845 || TREE_CODE (type) == COMPLEX_TYPE));
847 MEM_NOTRAP_P (slot) = 1;
849 return slot;
852 /* Allocate a temporary stack slot and record it for possible later
853 reuse. First three arguments are same as in preceding function. */
856 assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
858 return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
861 /* Assign a temporary.
862 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
863 and so that should be used in error messages. In either case, we
864 allocate of the given type.
865 KEEP is as for assign_stack_temp.
866 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
867 it is 0 if a register is OK.
868 DONT_PROMOTE is 1 if we should not promote values in register
869 to wider modes. */
872 assign_temp (tree type_or_decl, int keep, int memory_required,
873 int dont_promote ATTRIBUTE_UNUSED)
875 tree type, decl;
876 enum machine_mode mode;
877 #ifdef PROMOTE_MODE
878 int unsignedp;
879 #endif
881 if (DECL_P (type_or_decl))
882 decl = type_or_decl, type = TREE_TYPE (decl);
883 else
884 decl = NULL, type = type_or_decl;
886 mode = TYPE_MODE (type);
887 #ifdef PROMOTE_MODE
888 unsignedp = TYPE_UNSIGNED (type);
889 #endif
891 if (mode == BLKmode || memory_required)
893 HOST_WIDE_INT size = int_size_in_bytes (type);
894 rtx tmp;
896 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
897 problems with allocating the stack space. */
898 if (size == 0)
899 size = 1;
901 /* Unfortunately, we don't yet know how to allocate variable-sized
902 temporaries. However, sometimes we can find a fixed upper limit on
903 the size, so try that instead. */
904 else if (size == -1)
905 size = max_int_size_in_bytes (type);
907 /* The size of the temporary may be too large to fit into an integer. */
908 /* ??? Not sure this should happen except for user silliness, so limit
909 this to things that aren't compiler-generated temporaries. The
910 rest of the time we'll die in assign_stack_temp_for_type. */
911 if (decl && size == -1
912 && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
914 error ("size of variable %q+D is too large", decl);
915 size = 1;
918 tmp = assign_stack_temp_for_type (mode, size, keep, type);
919 return tmp;
922 #ifdef PROMOTE_MODE
923 if (! dont_promote)
924 mode = promote_mode (type, mode, &unsignedp, 0);
925 #endif
927 return gen_reg_rtx (mode);
930 /* Combine temporary stack slots which are adjacent on the stack.
932 This allows for better use of already allocated stack space. This is only
933 done for BLKmode slots because we can be sure that we won't have alignment
934 problems in this case. */
936 static void
937 combine_temp_slots (void)
939 struct temp_slot *p, *q, *next, *next_q;
940 int num_slots;
942 /* We can't combine slots, because the information about which slot
943 is in which alias set will be lost. */
944 if (flag_strict_aliasing)
945 return;
947 /* If there are a lot of temp slots, don't do anything unless
948 high levels of optimization. */
949 if (! flag_expensive_optimizations)
950 for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
951 if (num_slots > 100 || (num_slots > 10 && optimize == 0))
952 return;
954 for (p = avail_temp_slots; p; p = next)
956 int delete_p = 0;
958 next = p->next;
960 if (GET_MODE (p->slot) != BLKmode)
961 continue;
963 for (q = p->next; q; q = next_q)
965 int delete_q = 0;
967 next_q = q->next;
969 if (GET_MODE (q->slot) != BLKmode)
970 continue;
972 if (p->base_offset + p->full_size == q->base_offset)
974 /* Q comes after P; combine Q into P. */
975 p->size += q->size;
976 p->full_size += q->full_size;
977 delete_q = 1;
979 else if (q->base_offset + q->full_size == p->base_offset)
981 /* P comes after Q; combine P into Q. */
982 q->size += p->size;
983 q->full_size += p->full_size;
984 delete_p = 1;
985 break;
987 if (delete_q)
988 cut_slot_from_list (q, &avail_temp_slots);
991 /* Either delete P or advance past it. */
992 if (delete_p)
993 cut_slot_from_list (p, &avail_temp_slots);
997 /* Indicate that NEW_RTX is an alternate way of referring to the temp
998 slot that previously was known by OLD_RTX. */
1000 void
1001 update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1003 struct temp_slot *p;
1005 if (rtx_equal_p (old_rtx, new_rtx))
1006 return;
1008 p = find_temp_slot_from_address (old_rtx);
1010 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1011 NEW_RTX is a register, see if one operand of the PLUS is a
1012 temporary location. If so, NEW_RTX points into it. Otherwise,
1013 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1014 in common between them. If so, try a recursive call on those
1015 values. */
1016 if (p == 0)
1018 if (GET_CODE (old_rtx) != PLUS)
1019 return;
1021 if (REG_P (new_rtx))
1023 update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1024 update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1025 return;
1027 else if (GET_CODE (new_rtx) != PLUS)
1028 return;
1030 if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1031 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1032 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1033 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1034 else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1035 update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1036 else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1037 update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1039 return;
1042 /* Otherwise add an alias for the temp's address. */
1043 insert_temp_slot_address (new_rtx, p);
1046 /* If X could be a reference to a temporary slot, mark the fact that its
1047 address was taken. */
1049 void
1050 mark_temp_addr_taken (rtx x)
1052 struct temp_slot *p;
1054 if (x == 0)
1055 return;
1057 /* If X is not in memory or is at a constant address, it cannot be in
1058 a temporary slot. */
1059 if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1060 return;
1062 p = find_temp_slot_from_address (XEXP (x, 0));
1063 if (p != 0)
1064 p->addr_taken = 1;
1067 /* If X could be a reference to a temporary slot, mark that slot as
1068 belonging to the to one level higher than the current level. If X
1069 matched one of our slots, just mark that one. Otherwise, we can't
1070 easily predict which it is, so upgrade all of them. Kept slots
1071 need not be touched.
1073 This is called when an ({...}) construct occurs and a statement
1074 returns a value in memory. */
1076 void
1077 preserve_temp_slots (rtx x)
1079 struct temp_slot *p = 0, *next;
1081 /* If there is no result, we still might have some objects whose address
1082 were taken, so we need to make sure they stay around. */
1083 if (x == 0)
1085 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1087 next = p->next;
1089 if (p->addr_taken)
1090 move_slot_to_level (p, temp_slot_level - 1);
1093 return;
1096 /* If X is a register that is being used as a pointer, see if we have
1097 a temporary slot we know it points to. To be consistent with
1098 the code below, we really should preserve all non-kept slots
1099 if we can't find a match, but that seems to be much too costly. */
1100 if (REG_P (x) && REG_POINTER (x))
1101 p = find_temp_slot_from_address (x);
1103 /* If X is not in memory or is at a constant address, it cannot be in
1104 a temporary slot, but it can contain something whose address was
1105 taken. */
1106 if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1108 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1110 next = p->next;
1112 if (p->addr_taken)
1113 move_slot_to_level (p, temp_slot_level - 1);
1116 return;
1119 /* First see if we can find a match. */
1120 if (p == 0)
1121 p = find_temp_slot_from_address (XEXP (x, 0));
1123 if (p != 0)
1125 /* Move everything at our level whose address was taken to our new
1126 level in case we used its address. */
1127 struct temp_slot *q;
1129 if (p->level == temp_slot_level)
1131 for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1133 next = q->next;
1135 if (p != q && q->addr_taken)
1136 move_slot_to_level (q, temp_slot_level - 1);
1139 move_slot_to_level (p, temp_slot_level - 1);
1140 p->addr_taken = 0;
1142 return;
1145 /* Otherwise, preserve all non-kept slots at this level. */
1146 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1148 next = p->next;
1150 if (!p->keep)
1151 move_slot_to_level (p, temp_slot_level - 1);
1155 /* Free all temporaries used so far. This is normally called at the
1156 end of generating code for a statement. */
1158 void
1159 free_temp_slots (void)
1161 struct temp_slot *p, *next;
1163 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1165 next = p->next;
1167 if (!p->keep)
1168 make_slot_available (p);
1171 remove_unused_temp_slot_addresses ();
1172 combine_temp_slots ();
1175 /* Push deeper into the nesting level for stack temporaries. */
1177 void
1178 push_temp_slots (void)
1180 temp_slot_level++;
1183 /* Pop a temporary nesting level. All slots in use in the current level
1184 are freed. */
1186 void
1187 pop_temp_slots (void)
1189 struct temp_slot *p, *next;
1191 for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1193 next = p->next;
1194 make_slot_available (p);
1197 remove_unused_temp_slot_addresses ();
1198 combine_temp_slots ();
1200 temp_slot_level--;
1203 /* Initialize temporary slots. */
1205 void
1206 init_temp_slots (void)
1208 /* We have not allocated any temporaries yet. */
1209 avail_temp_slots = 0;
1210 used_temp_slots = 0;
1211 temp_slot_level = 0;
1213 /* Set up the table to map addresses to temp slots. */
1214 if (! temp_slot_address_table)
1215 temp_slot_address_table = htab_create_ggc (32,
1216 temp_slot_address_hash,
1217 temp_slot_address_eq,
1218 NULL);
1219 else
1220 htab_empty (temp_slot_address_table);
1223 /* These routines are responsible for converting virtual register references
1224 to the actual hard register references once RTL generation is complete.
1226 The following four variables are used for communication between the
1227 routines. They contain the offsets of the virtual registers from their
1228 respective hard registers. */
1230 static int in_arg_offset;
1231 static int var_offset;
1232 static int dynamic_offset;
1233 static int out_arg_offset;
1234 static int cfa_offset;
1236 /* In most machines, the stack pointer register is equivalent to the bottom
1237 of the stack. */
1239 #ifndef STACK_POINTER_OFFSET
1240 #define STACK_POINTER_OFFSET 0
1241 #endif
1243 /* If not defined, pick an appropriate default for the offset of dynamically
1244 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1245 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1247 #ifndef STACK_DYNAMIC_OFFSET
1249 /* The bottom of the stack points to the actual arguments. If
1250 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1251 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1252 stack space for register parameters is not pushed by the caller, but
1253 rather part of the fixed stack areas and hence not included in
1254 `crtl->outgoing_args_size'. Nevertheless, we must allow
1255 for it when allocating stack dynamic objects. */
1257 #if defined(REG_PARM_STACK_SPACE)
1258 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1259 ((ACCUMULATE_OUTGOING_ARGS \
1260 ? (crtl->outgoing_args_size \
1261 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1262 : REG_PARM_STACK_SPACE (FNDECL))) \
1263 : 0) + (STACK_POINTER_OFFSET))
1264 #else
1265 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1266 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1267 + (STACK_POINTER_OFFSET))
1268 #endif
1269 #endif
1272 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1273 is a virtual register, return the equivalent hard register and set the
1274 offset indirectly through the pointer. Otherwise, return 0. */
1276 static rtx
1277 instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1279 rtx new_rtx;
1280 HOST_WIDE_INT offset;
1282 if (x == virtual_incoming_args_rtx)
1284 if (stack_realign_drap)
1286 /* Replace virtual_incoming_args_rtx with internal arg
1287 pointer if DRAP is used to realign stack. */
1288 new_rtx = crtl->args.internal_arg_pointer;
1289 offset = 0;
1291 else
1292 new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1294 else if (x == virtual_stack_vars_rtx)
1295 new_rtx = frame_pointer_rtx, offset = var_offset;
1296 else if (x == virtual_stack_dynamic_rtx)
1297 new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1298 else if (x == virtual_outgoing_args_rtx)
1299 new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1300 else if (x == virtual_cfa_rtx)
1302 #ifdef FRAME_POINTER_CFA_OFFSET
1303 new_rtx = frame_pointer_rtx;
1304 #else
1305 new_rtx = arg_pointer_rtx;
1306 #endif
1307 offset = cfa_offset;
1309 else
1310 return NULL_RTX;
1312 *poffset = offset;
1313 return new_rtx;
1316 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1317 Instantiate any virtual registers present inside of *LOC. The expression
1318 is simplified, as much as possible, but is not to be considered "valid"
1319 in any sense implied by the target. If any change is made, set CHANGED
1320 to true. */
1322 static int
1323 instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1325 HOST_WIDE_INT offset;
1326 bool *changed = (bool *) data;
1327 rtx x, new_rtx;
1329 x = *loc;
1330 if (x == 0)
1331 return 0;
1333 switch (GET_CODE (x))
1335 case REG:
1336 new_rtx = instantiate_new_reg (x, &offset);
1337 if (new_rtx)
1339 *loc = plus_constant (new_rtx, offset);
1340 if (changed)
1341 *changed = true;
1343 return -1;
1345 case PLUS:
1346 new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1347 if (new_rtx)
1349 new_rtx = plus_constant (new_rtx, offset);
1350 *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1351 if (changed)
1352 *changed = true;
1353 return -1;
1356 /* FIXME -- from old code */
1357 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1358 we can commute the PLUS and SUBREG because pointers into the
1359 frame are well-behaved. */
1360 break;
1362 default:
1363 break;
1366 return 0;
1369 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1370 matches the predicate for insn CODE operand OPERAND. */
1372 static int
1373 safe_insn_predicate (int code, int operand, rtx x)
1375 const struct insn_operand_data *op_data;
1377 if (code < 0)
1378 return true;
1380 op_data = &insn_data[code].operand[operand];
1381 if (op_data->predicate == NULL)
1382 return true;
1384 return op_data->predicate (x, op_data->mode);
1387 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1388 registers present inside of insn. The result will be a valid insn. */
1390 static void
1391 instantiate_virtual_regs_in_insn (rtx insn)
1393 HOST_WIDE_INT offset;
1394 int insn_code, i;
1395 bool any_change = false;
1396 rtx set, new_rtx, x, seq;
1398 /* There are some special cases to be handled first. */
1399 set = single_set (insn);
1400 if (set)
1402 /* We're allowed to assign to a virtual register. This is interpreted
1403 to mean that the underlying register gets assigned the inverse
1404 transformation. This is used, for example, in the handling of
1405 non-local gotos. */
1406 new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1407 if (new_rtx)
1409 start_sequence ();
1411 for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1412 x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1413 GEN_INT (-offset));
1414 x = force_operand (x, new_rtx);
1415 if (x != new_rtx)
1416 emit_move_insn (new_rtx, x);
1418 seq = get_insns ();
1419 end_sequence ();
1421 emit_insn_before (seq, insn);
1422 delete_insn (insn);
1423 return;
1426 /* Handle a straight copy from a virtual register by generating a
1427 new add insn. The difference between this and falling through
1428 to the generic case is avoiding a new pseudo and eliminating a
1429 move insn in the initial rtl stream. */
1430 new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1431 if (new_rtx && offset != 0
1432 && REG_P (SET_DEST (set))
1433 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1435 start_sequence ();
1437 x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1438 new_rtx, GEN_INT (offset), SET_DEST (set),
1439 1, OPTAB_LIB_WIDEN);
1440 if (x != SET_DEST (set))
1441 emit_move_insn (SET_DEST (set), x);
1443 seq = get_insns ();
1444 end_sequence ();
1446 emit_insn_before (seq, insn);
1447 delete_insn (insn);
1448 return;
1451 extract_insn (insn);
1452 insn_code = INSN_CODE (insn);
1454 /* Handle a plus involving a virtual register by determining if the
1455 operands remain valid if they're modified in place. */
1456 if (GET_CODE (SET_SRC (set)) == PLUS
1457 && recog_data.n_operands >= 3
1458 && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1459 && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1460 && CONST_INT_P (recog_data.operand[2])
1461 && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1463 offset += INTVAL (recog_data.operand[2]);
1465 /* If the sum is zero, then replace with a plain move. */
1466 if (offset == 0
1467 && REG_P (SET_DEST (set))
1468 && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1470 start_sequence ();
1471 emit_move_insn (SET_DEST (set), new_rtx);
1472 seq = get_insns ();
1473 end_sequence ();
1475 emit_insn_before (seq, insn);
1476 delete_insn (insn);
1477 return;
1480 x = gen_int_mode (offset, recog_data.operand_mode[2]);
1482 /* Using validate_change and apply_change_group here leaves
1483 recog_data in an invalid state. Since we know exactly what
1484 we want to check, do those two by hand. */
1485 if (safe_insn_predicate (insn_code, 1, new_rtx)
1486 && safe_insn_predicate (insn_code, 2, x))
1488 *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1489 *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1490 any_change = true;
1492 /* Fall through into the regular operand fixup loop in
1493 order to take care of operands other than 1 and 2. */
1497 else
1499 extract_insn (insn);
1500 insn_code = INSN_CODE (insn);
1503 /* In the general case, we expect virtual registers to appear only in
1504 operands, and then only as either bare registers or inside memories. */
1505 for (i = 0; i < recog_data.n_operands; ++i)
1507 x = recog_data.operand[i];
1508 switch (GET_CODE (x))
1510 case MEM:
1512 rtx addr = XEXP (x, 0);
1513 bool changed = false;
1515 for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1516 if (!changed)
1517 continue;
1519 start_sequence ();
1520 x = replace_equiv_address (x, addr);
1521 /* It may happen that the address with the virtual reg
1522 was valid (e.g. based on the virtual stack reg, which might
1523 be acceptable to the predicates with all offsets), whereas
1524 the address now isn't anymore, for instance when the address
1525 is still offsetted, but the base reg isn't virtual-stack-reg
1526 anymore. Below we would do a force_reg on the whole operand,
1527 but this insn might actually only accept memory. Hence,
1528 before doing that last resort, try to reload the address into
1529 a register, so this operand stays a MEM. */
1530 if (!safe_insn_predicate (insn_code, i, x))
1532 addr = force_reg (GET_MODE (addr), addr);
1533 x = replace_equiv_address (x, addr);
1535 seq = get_insns ();
1536 end_sequence ();
1537 if (seq)
1538 emit_insn_before (seq, insn);
1540 break;
1542 case REG:
1543 new_rtx = instantiate_new_reg (x, &offset);
1544 if (new_rtx == NULL)
1545 continue;
1546 if (offset == 0)
1547 x = new_rtx;
1548 else
1550 start_sequence ();
1552 /* Careful, special mode predicates may have stuff in
1553 insn_data[insn_code].operand[i].mode that isn't useful
1554 to us for computing a new value. */
1555 /* ??? Recognize address_operand and/or "p" constraints
1556 to see if (plus new offset) is a valid before we put
1557 this through expand_simple_binop. */
1558 x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1559 GEN_INT (offset), NULL_RTX,
1560 1, OPTAB_LIB_WIDEN);
1561 seq = get_insns ();
1562 end_sequence ();
1563 emit_insn_before (seq, insn);
1565 break;
1567 case SUBREG:
1568 new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1569 if (new_rtx == NULL)
1570 continue;
1571 if (offset != 0)
1573 start_sequence ();
1574 new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1575 GEN_INT (offset), NULL_RTX,
1576 1, OPTAB_LIB_WIDEN);
1577 seq = get_insns ();
1578 end_sequence ();
1579 emit_insn_before (seq, insn);
1581 x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1582 GET_MODE (new_rtx), SUBREG_BYTE (x));
1583 gcc_assert (x);
1584 break;
1586 default:
1587 continue;
1590 /* At this point, X contains the new value for the operand.
1591 Validate the new value vs the insn predicate. Note that
1592 asm insns will have insn_code -1 here. */
1593 if (!safe_insn_predicate (insn_code, i, x))
1595 start_sequence ();
1596 x = force_reg (insn_data[insn_code].operand[i].mode, x);
1597 seq = get_insns ();
1598 end_sequence ();
1599 if (seq)
1600 emit_insn_before (seq, insn);
1603 *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1604 any_change = true;
1607 if (any_change)
1609 /* Propagate operand changes into the duplicates. */
1610 for (i = 0; i < recog_data.n_dups; ++i)
1611 *recog_data.dup_loc[i]
1612 = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1614 /* Force re-recognition of the instruction for validation. */
1615 INSN_CODE (insn) = -1;
1618 if (asm_noperands (PATTERN (insn)) >= 0)
1620 if (!check_asm_operands (PATTERN (insn)))
1622 error_for_asm (insn, "impossible constraint in %<asm%>");
1623 delete_insn (insn);
1626 else
1628 if (recog_memoized (insn) < 0)
1629 fatal_insn_not_found (insn);
1633 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1634 do any instantiation required. */
1636 void
1637 instantiate_decl_rtl (rtx x)
1639 rtx addr;
1641 if (x == 0)
1642 return;
1644 /* If this is a CONCAT, recurse for the pieces. */
1645 if (GET_CODE (x) == CONCAT)
1647 instantiate_decl_rtl (XEXP (x, 0));
1648 instantiate_decl_rtl (XEXP (x, 1));
1649 return;
1652 /* If this is not a MEM, no need to do anything. Similarly if the
1653 address is a constant or a register that is not a virtual register. */
1654 if (!MEM_P (x))
1655 return;
1657 addr = XEXP (x, 0);
1658 if (CONSTANT_P (addr)
1659 || (REG_P (addr)
1660 && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1661 || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1662 return;
1664 for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1667 /* Helper for instantiate_decls called via walk_tree: Process all decls
1668 in the given DECL_VALUE_EXPR. */
1670 static tree
1671 instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1673 tree t = *tp;
1674 if (! EXPR_P (t))
1676 *walk_subtrees = 0;
1677 if (DECL_P (t) && DECL_RTL_SET_P (t))
1678 instantiate_decl_rtl (DECL_RTL (t));
1680 return NULL;
1683 /* Subroutine of instantiate_decls: Process all decls in the given
1684 BLOCK node and all its subblocks. */
1686 static void
1687 instantiate_decls_1 (tree let)
1689 tree t;
1691 for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
1693 if (DECL_RTL_SET_P (t))
1694 instantiate_decl_rtl (DECL_RTL (t));
1695 if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1697 tree v = DECL_VALUE_EXPR (t);
1698 walk_tree (&v, instantiate_expr, NULL, NULL);
1702 /* Process all subblocks. */
1703 for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1704 instantiate_decls_1 (t);
1707 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1708 all virtual registers in their DECL_RTL's. */
1710 static void
1711 instantiate_decls (tree fndecl)
1713 tree decl, t, next;
1715 /* Process all parameters of the function. */
1716 for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
1718 instantiate_decl_rtl (DECL_RTL (decl));
1719 instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1720 if (DECL_HAS_VALUE_EXPR_P (decl))
1722 tree v = DECL_VALUE_EXPR (decl);
1723 walk_tree (&v, instantiate_expr, NULL, NULL);
1727 /* Now process all variables defined in the function or its subblocks. */
1728 instantiate_decls_1 (DECL_INITIAL (fndecl));
1730 t = cfun->local_decls;
1731 cfun->local_decls = NULL_TREE;
1732 for (; t; t = next)
1734 next = TREE_CHAIN (t);
1735 decl = TREE_VALUE (t);
1736 if (DECL_RTL_SET_P (decl))
1737 instantiate_decl_rtl (DECL_RTL (decl));
1738 ggc_free (t);
1742 /* Pass through the INSNS of function FNDECL and convert virtual register
1743 references to hard register references. */
1745 static unsigned int
1746 instantiate_virtual_regs (void)
1748 rtx insn;
1750 /* Compute the offsets to use for this function. */
1751 in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1752 var_offset = STARTING_FRAME_OFFSET;
1753 dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1754 out_arg_offset = STACK_POINTER_OFFSET;
1755 #ifdef FRAME_POINTER_CFA_OFFSET
1756 cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1757 #else
1758 cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1759 #endif
1761 /* Initialize recognition, indicating that volatile is OK. */
1762 init_recog ();
1764 /* Scan through all the insns, instantiating every virtual register still
1765 present. */
1766 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1767 if (INSN_P (insn))
1769 /* These patterns in the instruction stream can never be recognized.
1770 Fortunately, they shouldn't contain virtual registers either. */
1771 if (GET_CODE (PATTERN (insn)) == USE
1772 || GET_CODE (PATTERN (insn)) == CLOBBER
1773 || GET_CODE (PATTERN (insn)) == ADDR_VEC
1774 || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1775 || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1776 continue;
1778 instantiate_virtual_regs_in_insn (insn);
1780 if (INSN_DELETED_P (insn))
1781 continue;
1783 for_each_rtx (&REG_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1785 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1786 if (CALL_P (insn))
1787 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1788 instantiate_virtual_regs_in_rtx, NULL);
1791 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1792 instantiate_decls (current_function_decl);
1794 targetm.instantiate_decls ();
1796 /* Indicate that, from now on, assign_stack_local should use
1797 frame_pointer_rtx. */
1798 virtuals_instantiated = 1;
1799 return 0;
1802 struct rtl_opt_pass pass_instantiate_virtual_regs =
1805 RTL_PASS,
1806 "vregs", /* name */
1807 NULL, /* gate */
1808 instantiate_virtual_regs, /* execute */
1809 NULL, /* sub */
1810 NULL, /* next */
1811 0, /* static_pass_number */
1812 TV_NONE, /* tv_id */
1813 0, /* properties_required */
1814 0, /* properties_provided */
1815 0, /* properties_destroyed */
1816 0, /* todo_flags_start */
1817 TODO_dump_func /* todo_flags_finish */
1822 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1823 This means a type for which function calls must pass an address to the
1824 function or get an address back from the function.
1825 EXP may be a type node or an expression (whose type is tested). */
1828 aggregate_value_p (const_tree exp, const_tree fntype)
1830 int i, regno, nregs;
1831 rtx reg;
1833 const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1835 /* DECL node associated with FNTYPE when relevant, which we might need to
1836 check for by-invisible-reference returns, typically for CALL_EXPR input
1837 EXPressions. */
1838 const_tree fndecl = NULL_TREE;
1840 if (fntype)
1841 switch (TREE_CODE (fntype))
1843 case CALL_EXPR:
1844 fndecl = get_callee_fndecl (fntype);
1845 fntype = (fndecl
1846 ? TREE_TYPE (fndecl)
1847 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
1848 break;
1849 case FUNCTION_DECL:
1850 fndecl = fntype;
1851 fntype = TREE_TYPE (fndecl);
1852 break;
1853 case FUNCTION_TYPE:
1854 case METHOD_TYPE:
1855 break;
1856 case IDENTIFIER_NODE:
1857 fntype = 0;
1858 break;
1859 default:
1860 /* We don't expect other rtl types here. */
1861 gcc_unreachable ();
1864 if (TREE_CODE (type) == VOID_TYPE)
1865 return 0;
1867 /* If the front end has decided that this needs to be passed by
1868 reference, do so. */
1869 if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1870 && DECL_BY_REFERENCE (exp))
1871 return 1;
1873 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1874 called function RESULT_DECL, meaning the function returns in memory by
1875 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1876 on the function type, which used to be the way to request such a return
1877 mechanism but might now be causing troubles at gimplification time if
1878 temporaries with the function type need to be created. */
1879 if (TREE_CODE (exp) == CALL_EXPR && fndecl && DECL_RESULT (fndecl)
1880 && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
1881 return 1;
1883 if (targetm.calls.return_in_memory (type, fntype))
1884 return 1;
1885 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1886 and thus can't be returned in registers. */
1887 if (TREE_ADDRESSABLE (type))
1888 return 1;
1889 if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1890 return 1;
1891 /* Make sure we have suitable call-clobbered regs to return
1892 the value in; if not, we must return it in memory. */
1893 reg = hard_function_value (type, 0, fntype, 0);
1895 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1896 it is OK. */
1897 if (!REG_P (reg))
1898 return 0;
1900 regno = REGNO (reg);
1901 nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
1902 for (i = 0; i < nregs; i++)
1903 if (! call_used_regs[regno + i])
1904 return 1;
1905 return 0;
1908 /* Return true if we should assign DECL a pseudo register; false if it
1909 should live on the local stack. */
1911 bool
1912 use_register_for_decl (const_tree decl)
1914 if (!targetm.calls.allocate_stack_slots_for_args())
1915 return true;
1917 /* Honor volatile. */
1918 if (TREE_SIDE_EFFECTS (decl))
1919 return false;
1921 /* Honor addressability. */
1922 if (TREE_ADDRESSABLE (decl))
1923 return false;
1925 /* Only register-like things go in registers. */
1926 if (DECL_MODE (decl) == BLKmode)
1927 return false;
1929 /* If -ffloat-store specified, don't put explicit float variables
1930 into registers. */
1931 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1932 propagates values across these stores, and it probably shouldn't. */
1933 if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
1934 return false;
1936 /* If we're not interested in tracking debugging information for
1937 this decl, then we can certainly put it in a register. */
1938 if (DECL_IGNORED_P (decl))
1939 return true;
1941 if (optimize)
1942 return true;
1944 if (!DECL_REGISTER (decl))
1945 return false;
1947 switch (TREE_CODE (TREE_TYPE (decl)))
1949 case RECORD_TYPE:
1950 case UNION_TYPE:
1951 case QUAL_UNION_TYPE:
1952 /* When not optimizing, disregard register keyword for variables with
1953 types containing methods, otherwise the methods won't be callable
1954 from the debugger. */
1955 if (TYPE_METHODS (TREE_TYPE (decl)))
1956 return false;
1957 break;
1958 default:
1959 break;
1962 return true;
1965 /* Return true if TYPE should be passed by invisible reference. */
1967 bool
1968 pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1969 tree type, bool named_arg)
1971 if (type)
1973 /* If this type contains non-trivial constructors, then it is
1974 forbidden for the middle-end to create any new copies. */
1975 if (TREE_ADDRESSABLE (type))
1976 return true;
1978 /* GCC post 3.4 passes *all* variable sized types by reference. */
1979 if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
1980 return true;
1983 return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
1986 /* Return true if TYPE, which is passed by reference, should be callee
1987 copied instead of caller copied. */
1989 bool
1990 reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
1991 tree type, bool named_arg)
1993 if (type && TREE_ADDRESSABLE (type))
1994 return false;
1995 return targetm.calls.callee_copies (ca, mode, type, named_arg);
1998 /* Structures to communicate between the subroutines of assign_parms.
1999 The first holds data persistent across all parameters, the second
2000 is cleared out for each parameter. */
2002 struct assign_parm_data_all
2004 CUMULATIVE_ARGS args_so_far;
2005 struct args_size stack_args_size;
2006 tree function_result_decl;
2007 tree orig_fnargs;
2008 rtx first_conversion_insn;
2009 rtx last_conversion_insn;
2010 HOST_WIDE_INT pretend_args_size;
2011 HOST_WIDE_INT extra_pretend_bytes;
2012 int reg_parm_stack_space;
2015 struct assign_parm_data_one
2017 tree nominal_type;
2018 tree passed_type;
2019 rtx entry_parm;
2020 rtx stack_parm;
2021 enum machine_mode nominal_mode;
2022 enum machine_mode passed_mode;
2023 enum machine_mode promoted_mode;
2024 struct locate_and_pad_arg_data locate;
2025 int partial;
2026 BOOL_BITFIELD named_arg : 1;
2027 BOOL_BITFIELD passed_pointer : 1;
2028 BOOL_BITFIELD on_stack : 1;
2029 BOOL_BITFIELD loaded_in_reg : 1;
2032 /* A subroutine of assign_parms. Initialize ALL. */
2034 static void
2035 assign_parms_initialize_all (struct assign_parm_data_all *all)
2037 tree fntype;
2039 memset (all, 0, sizeof (*all));
2041 fntype = TREE_TYPE (current_function_decl);
2043 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2044 INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2045 #else
2046 INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2047 current_function_decl, -1);
2048 #endif
2050 #ifdef REG_PARM_STACK_SPACE
2051 all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2052 #endif
2055 /* If ARGS contains entries with complex types, split the entry into two
2056 entries of the component type. Return a new list of substitutions are
2057 needed, else the old list. */
2059 static tree
2060 split_complex_args (tree args)
2062 tree p;
2064 /* Before allocating memory, check for the common case of no complex. */
2065 for (p = args; p; p = TREE_CHAIN (p))
2067 tree type = TREE_TYPE (p);
2068 if (TREE_CODE (type) == COMPLEX_TYPE
2069 && targetm.calls.split_complex_arg (type))
2070 goto found;
2072 return args;
2074 found:
2075 args = copy_list (args);
2077 for (p = args; p; p = TREE_CHAIN (p))
2079 tree type = TREE_TYPE (p);
2080 if (TREE_CODE (type) == COMPLEX_TYPE
2081 && targetm.calls.split_complex_arg (type))
2083 tree decl;
2084 tree subtype = TREE_TYPE (type);
2085 bool addressable = TREE_ADDRESSABLE (p);
2087 /* Rewrite the PARM_DECL's type with its component. */
2088 TREE_TYPE (p) = subtype;
2089 DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2090 DECL_MODE (p) = VOIDmode;
2091 DECL_SIZE (p) = NULL;
2092 DECL_SIZE_UNIT (p) = NULL;
2093 /* If this arg must go in memory, put it in a pseudo here.
2094 We can't allow it to go in memory as per normal parms,
2095 because the usual place might not have the imag part
2096 adjacent to the real part. */
2097 DECL_ARTIFICIAL (p) = addressable;
2098 DECL_IGNORED_P (p) = addressable;
2099 TREE_ADDRESSABLE (p) = 0;
2100 layout_decl (p, 0);
2102 /* Build a second synthetic decl. */
2103 decl = build_decl (EXPR_LOCATION (p),
2104 PARM_DECL, NULL_TREE, subtype);
2105 DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2106 DECL_ARTIFICIAL (decl) = addressable;
2107 DECL_IGNORED_P (decl) = addressable;
2108 layout_decl (decl, 0);
2110 /* Splice it in; skip the new decl. */
2111 TREE_CHAIN (decl) = TREE_CHAIN (p);
2112 TREE_CHAIN (p) = decl;
2113 p = decl;
2117 return args;
2120 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2121 the hidden struct return argument, and (abi willing) complex args.
2122 Return the new parameter list. */
2124 static tree
2125 assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2127 tree fndecl = current_function_decl;
2128 tree fntype = TREE_TYPE (fndecl);
2129 tree fnargs = DECL_ARGUMENTS (fndecl);
2131 /* If struct value address is treated as the first argument, make it so. */
2132 if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2133 && ! cfun->returns_pcc_struct
2134 && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2136 tree type = build_pointer_type (TREE_TYPE (fntype));
2137 tree decl;
2139 decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2140 PARM_DECL, NULL_TREE, type);
2141 DECL_ARG_TYPE (decl) = type;
2142 DECL_ARTIFICIAL (decl) = 1;
2143 DECL_IGNORED_P (decl) = 1;
2145 TREE_CHAIN (decl) = fnargs;
2146 fnargs = decl;
2147 all->function_result_decl = decl;
2150 all->orig_fnargs = fnargs;
2152 /* If the target wants to split complex arguments into scalars, do so. */
2153 if (targetm.calls.split_complex_arg)
2154 fnargs = split_complex_args (fnargs);
2156 return fnargs;
2159 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2160 data for the parameter. Incorporate ABI specifics such as pass-by-
2161 reference and type promotion. */
2163 static void
2164 assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2165 struct assign_parm_data_one *data)
2167 tree nominal_type, passed_type;
2168 enum machine_mode nominal_mode, passed_mode, promoted_mode;
2170 memset (data, 0, sizeof (*data));
2172 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2173 if (!cfun->stdarg)
2174 data->named_arg = 1; /* No variadic parms. */
2175 else if (TREE_CHAIN (parm))
2176 data->named_arg = 1; /* Not the last non-variadic parm. */
2177 else if (targetm.calls.strict_argument_naming (&all->args_so_far))
2178 data->named_arg = 1; /* Only variadic ones are unnamed. */
2179 else
2180 data->named_arg = 0; /* Treat as variadic. */
2182 nominal_type = TREE_TYPE (parm);
2183 passed_type = DECL_ARG_TYPE (parm);
2185 /* Look out for errors propagating this far. Also, if the parameter's
2186 type is void then its value doesn't matter. */
2187 if (TREE_TYPE (parm) == error_mark_node
2188 /* This can happen after weird syntax errors
2189 or if an enum type is defined among the parms. */
2190 || TREE_CODE (parm) != PARM_DECL
2191 || passed_type == NULL
2192 || VOID_TYPE_P (nominal_type))
2194 nominal_type = passed_type = void_type_node;
2195 nominal_mode = passed_mode = promoted_mode = VOIDmode;
2196 goto egress;
2199 /* Find mode of arg as it is passed, and mode of arg as it should be
2200 during execution of this function. */
2201 passed_mode = TYPE_MODE (passed_type);
2202 nominal_mode = TYPE_MODE (nominal_type);
2204 /* If the parm is to be passed as a transparent union, use the type of
2205 the first field for the tests below. We have already verified that
2206 the modes are the same. */
2207 if (TREE_CODE (passed_type) == UNION_TYPE
2208 && TYPE_TRANSPARENT_UNION (passed_type))
2209 passed_type = TREE_TYPE (TYPE_FIELDS (passed_type));
2211 /* See if this arg was passed by invisible reference. */
2212 if (pass_by_reference (&all->args_so_far, passed_mode,
2213 passed_type, data->named_arg))
2215 passed_type = nominal_type = build_pointer_type (passed_type);
2216 data->passed_pointer = true;
2217 passed_mode = nominal_mode = Pmode;
2220 /* Find mode as it is passed by the ABI. */
2221 promoted_mode = passed_mode;
2222 if (targetm.calls.promote_function_args (TREE_TYPE (current_function_decl)))
2224 int unsignedp = TYPE_UNSIGNED (passed_type);
2225 promoted_mode = promote_mode (passed_type, promoted_mode,
2226 &unsignedp, 1);
2229 egress:
2230 data->nominal_type = nominal_type;
2231 data->passed_type = passed_type;
2232 data->nominal_mode = nominal_mode;
2233 data->passed_mode = passed_mode;
2234 data->promoted_mode = promoted_mode;
2237 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2239 static void
2240 assign_parms_setup_varargs (struct assign_parm_data_all *all,
2241 struct assign_parm_data_one *data, bool no_rtl)
2243 int varargs_pretend_bytes = 0;
2245 targetm.calls.setup_incoming_varargs (&all->args_so_far,
2246 data->promoted_mode,
2247 data->passed_type,
2248 &varargs_pretend_bytes, no_rtl);
2250 /* If the back-end has requested extra stack space, record how much is
2251 needed. Do not change pretend_args_size otherwise since it may be
2252 nonzero from an earlier partial argument. */
2253 if (varargs_pretend_bytes > 0)
2254 all->pretend_args_size = varargs_pretend_bytes;
2257 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2258 the incoming location of the current parameter. */
2260 static void
2261 assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2262 struct assign_parm_data_one *data)
2264 HOST_WIDE_INT pretend_bytes = 0;
2265 rtx entry_parm;
2266 bool in_regs;
2268 if (data->promoted_mode == VOIDmode)
2270 data->entry_parm = data->stack_parm = const0_rtx;
2271 return;
2274 #ifdef FUNCTION_INCOMING_ARG
2275 entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2276 data->passed_type, data->named_arg);
2277 #else
2278 entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2279 data->passed_type, data->named_arg);
2280 #endif
2282 if (entry_parm == 0)
2283 data->promoted_mode = data->passed_mode;
2285 /* Determine parm's home in the stack, in case it arrives in the stack
2286 or we should pretend it did. Compute the stack position and rtx where
2287 the argument arrives and its size.
2289 There is one complexity here: If this was a parameter that would
2290 have been passed in registers, but wasn't only because it is
2291 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2292 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2293 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2294 as it was the previous time. */
2295 in_regs = entry_parm != 0;
2296 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2297 in_regs = true;
2298 #endif
2299 if (!in_regs && !data->named_arg)
2301 if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2303 rtx tem;
2304 #ifdef FUNCTION_INCOMING_ARG
2305 tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2306 data->passed_type, true);
2307 #else
2308 tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2309 data->passed_type, true);
2310 #endif
2311 in_regs = tem != NULL;
2315 /* If this parameter was passed both in registers and in the stack, use
2316 the copy on the stack. */
2317 if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2318 data->passed_type))
2319 entry_parm = 0;
2321 if (entry_parm)
2323 int partial;
2325 partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2326 data->promoted_mode,
2327 data->passed_type,
2328 data->named_arg);
2329 data->partial = partial;
2331 /* The caller might already have allocated stack space for the
2332 register parameters. */
2333 if (partial != 0 && all->reg_parm_stack_space == 0)
2335 /* Part of this argument is passed in registers and part
2336 is passed on the stack. Ask the prologue code to extend
2337 the stack part so that we can recreate the full value.
2339 PRETEND_BYTES is the size of the registers we need to store.
2340 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2341 stack space that the prologue should allocate.
2343 Internally, gcc assumes that the argument pointer is aligned
2344 to STACK_BOUNDARY bits. This is used both for alignment
2345 optimizations (see init_emit) and to locate arguments that are
2346 aligned to more than PARM_BOUNDARY bits. We must preserve this
2347 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2348 a stack boundary. */
2350 /* We assume at most one partial arg, and it must be the first
2351 argument on the stack. */
2352 gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2354 pretend_bytes = partial;
2355 all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2357 /* We want to align relative to the actual stack pointer, so
2358 don't include this in the stack size until later. */
2359 all->extra_pretend_bytes = all->pretend_args_size;
2363 locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2364 entry_parm ? data->partial : 0, current_function_decl,
2365 &all->stack_args_size, &data->locate);
2367 /* Update parm_stack_boundary if this parameter is passed in the
2368 stack. */
2369 if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2370 crtl->parm_stack_boundary = data->locate.boundary;
2372 /* Adjust offsets to include the pretend args. */
2373 pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2374 data->locate.slot_offset.constant += pretend_bytes;
2375 data->locate.offset.constant += pretend_bytes;
2377 data->entry_parm = entry_parm;
2380 /* A subroutine of assign_parms. If there is actually space on the stack
2381 for this parm, count it in stack_args_size and return true. */
2383 static bool
2384 assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2385 struct assign_parm_data_one *data)
2387 /* Trivially true if we've no incoming register. */
2388 if (data->entry_parm == NULL)
2390 /* Also true if we're partially in registers and partially not,
2391 since we've arranged to drop the entire argument on the stack. */
2392 else if (data->partial != 0)
2394 /* Also true if the target says that it's passed in both registers
2395 and on the stack. */
2396 else if (GET_CODE (data->entry_parm) == PARALLEL
2397 && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2399 /* Also true if the target says that there's stack allocated for
2400 all register parameters. */
2401 else if (all->reg_parm_stack_space > 0)
2403 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2404 else
2405 return false;
2407 all->stack_args_size.constant += data->locate.size.constant;
2408 if (data->locate.size.var)
2409 ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2411 return true;
2414 /* A subroutine of assign_parms. Given that this parameter is allocated
2415 stack space by the ABI, find it. */
2417 static void
2418 assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2420 rtx offset_rtx, stack_parm;
2421 unsigned int align, boundary;
2423 /* If we're passing this arg using a reg, make its stack home the
2424 aligned stack slot. */
2425 if (data->entry_parm)
2426 offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2427 else
2428 offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2430 stack_parm = crtl->args.internal_arg_pointer;
2431 if (offset_rtx != const0_rtx)
2432 stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2433 stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2435 set_mem_attributes (stack_parm, parm, 1);
2436 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2437 while promoted mode's size is needed. */
2438 if (data->promoted_mode != BLKmode
2439 && data->promoted_mode != DECL_MODE (parm))
2441 set_mem_size (stack_parm, GEN_INT (GET_MODE_SIZE (data->promoted_mode)));
2442 if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm))
2444 int offset = subreg_lowpart_offset (DECL_MODE (parm),
2445 data->promoted_mode);
2446 if (offset)
2447 set_mem_offset (stack_parm,
2448 plus_constant (MEM_OFFSET (stack_parm), -offset));
2452 boundary = data->locate.boundary;
2453 align = BITS_PER_UNIT;
2455 /* If we're padding upward, we know that the alignment of the slot
2456 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2457 intentionally forcing upward padding. Otherwise we have to come
2458 up with a guess at the alignment based on OFFSET_RTX. */
2459 if (data->locate.where_pad != downward || data->entry_parm)
2460 align = boundary;
2461 else if (CONST_INT_P (offset_rtx))
2463 align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2464 align = align & -align;
2466 set_mem_align (stack_parm, align);
2468 if (data->entry_parm)
2469 set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2471 data->stack_parm = stack_parm;
2474 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2475 always valid and contiguous. */
2477 static void
2478 assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2480 rtx entry_parm = data->entry_parm;
2481 rtx stack_parm = data->stack_parm;
2483 /* If this parm was passed part in regs and part in memory, pretend it
2484 arrived entirely in memory by pushing the register-part onto the stack.
2485 In the special case of a DImode or DFmode that is split, we could put
2486 it together in a pseudoreg directly, but for now that's not worth
2487 bothering with. */
2488 if (data->partial != 0)
2490 /* Handle calls that pass values in multiple non-contiguous
2491 locations. The Irix 6 ABI has examples of this. */
2492 if (GET_CODE (entry_parm) == PARALLEL)
2493 emit_group_store (validize_mem (stack_parm), entry_parm,
2494 data->passed_type,
2495 int_size_in_bytes (data->passed_type));
2496 else
2498 gcc_assert (data->partial % UNITS_PER_WORD == 0);
2499 move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2500 data->partial / UNITS_PER_WORD);
2503 entry_parm = stack_parm;
2506 /* If we didn't decide this parm came in a register, by default it came
2507 on the stack. */
2508 else if (entry_parm == NULL)
2509 entry_parm = stack_parm;
2511 /* When an argument is passed in multiple locations, we can't make use
2512 of this information, but we can save some copying if the whole argument
2513 is passed in a single register. */
2514 else if (GET_CODE (entry_parm) == PARALLEL
2515 && data->nominal_mode != BLKmode
2516 && data->passed_mode != BLKmode)
2518 size_t i, len = XVECLEN (entry_parm, 0);
2520 for (i = 0; i < len; i++)
2521 if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2522 && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2523 && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2524 == data->passed_mode)
2525 && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2527 entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2528 break;
2532 data->entry_parm = entry_parm;
2535 /* A subroutine of assign_parms. Reconstitute any values which were
2536 passed in multiple registers and would fit in a single register. */
2538 static void
2539 assign_parm_remove_parallels (struct assign_parm_data_one *data)
2541 rtx entry_parm = data->entry_parm;
2543 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2544 This can be done with register operations rather than on the
2545 stack, even if we will store the reconstituted parameter on the
2546 stack later. */
2547 if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2549 rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2550 emit_group_store (parmreg, entry_parm, data->passed_type,
2551 GET_MODE_SIZE (GET_MODE (entry_parm)));
2552 entry_parm = parmreg;
2555 data->entry_parm = entry_parm;
2558 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2559 always valid and properly aligned. */
2561 static void
2562 assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2564 rtx stack_parm = data->stack_parm;
2566 /* If we can't trust the parm stack slot to be aligned enough for its
2567 ultimate type, don't use that slot after entry. We'll make another
2568 stack slot, if we need one. */
2569 if (stack_parm
2570 && ((STRICT_ALIGNMENT
2571 && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2572 || (data->nominal_type
2573 && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2574 && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2575 stack_parm = NULL;
2577 /* If parm was passed in memory, and we need to convert it on entry,
2578 don't store it back in that same slot. */
2579 else if (data->entry_parm == stack_parm
2580 && data->nominal_mode != BLKmode
2581 && data->nominal_mode != data->passed_mode)
2582 stack_parm = NULL;
2584 /* If stack protection is in effect for this function, don't leave any
2585 pointers in their passed stack slots. */
2586 else if (crtl->stack_protect_guard
2587 && (flag_stack_protect == 2
2588 || data->passed_pointer
2589 || POINTER_TYPE_P (data->nominal_type)))
2590 stack_parm = NULL;
2592 data->stack_parm = stack_parm;
2595 /* A subroutine of assign_parms. Return true if the current parameter
2596 should be stored as a BLKmode in the current frame. */
2598 static bool
2599 assign_parm_setup_block_p (struct assign_parm_data_one *data)
2601 if (data->nominal_mode == BLKmode)
2602 return true;
2603 if (GET_MODE (data->entry_parm) == BLKmode)
2604 return true;
2606 #ifdef BLOCK_REG_PADDING
2607 /* Only assign_parm_setup_block knows how to deal with register arguments
2608 that are padded at the least significant end. */
2609 if (REG_P (data->entry_parm)
2610 && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2611 && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2612 == (BYTES_BIG_ENDIAN ? upward : downward)))
2613 return true;
2614 #endif
2616 return false;
2619 /* A subroutine of assign_parms. Arrange for the parameter to be
2620 present and valid in DATA->STACK_RTL. */
2622 static void
2623 assign_parm_setup_block (struct assign_parm_data_all *all,
2624 tree parm, struct assign_parm_data_one *data)
2626 rtx entry_parm = data->entry_parm;
2627 rtx stack_parm = data->stack_parm;
2628 HOST_WIDE_INT size;
2629 HOST_WIDE_INT size_stored;
2631 if (GET_CODE (entry_parm) == PARALLEL)
2632 entry_parm = emit_group_move_into_temps (entry_parm);
2634 size = int_size_in_bytes (data->passed_type);
2635 size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2636 if (stack_parm == 0)
2638 DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2639 stack_parm = assign_stack_local (BLKmode, size_stored,
2640 DECL_ALIGN (parm));
2641 if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2642 PUT_MODE (stack_parm, GET_MODE (entry_parm));
2643 set_mem_attributes (stack_parm, parm, 1);
2646 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2647 calls that pass values in multiple non-contiguous locations. */
2648 if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2650 rtx mem;
2652 /* Note that we will be storing an integral number of words.
2653 So we have to be careful to ensure that we allocate an
2654 integral number of words. We do this above when we call
2655 assign_stack_local if space was not allocated in the argument
2656 list. If it was, this will not work if PARM_BOUNDARY is not
2657 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2658 if it becomes a problem. Exception is when BLKmode arrives
2659 with arguments not conforming to word_mode. */
2661 if (data->stack_parm == 0)
2663 else if (GET_CODE (entry_parm) == PARALLEL)
2665 else
2666 gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2668 mem = validize_mem (stack_parm);
2670 /* Handle values in multiple non-contiguous locations. */
2671 if (GET_CODE (entry_parm) == PARALLEL)
2673 push_to_sequence2 (all->first_conversion_insn,
2674 all->last_conversion_insn);
2675 emit_group_store (mem, entry_parm, data->passed_type, size);
2676 all->first_conversion_insn = get_insns ();
2677 all->last_conversion_insn = get_last_insn ();
2678 end_sequence ();
2681 else if (size == 0)
2684 /* If SIZE is that of a mode no bigger than a word, just use
2685 that mode's store operation. */
2686 else if (size <= UNITS_PER_WORD)
2688 enum machine_mode mode
2689 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2691 if (mode != BLKmode
2692 #ifdef BLOCK_REG_PADDING
2693 && (size == UNITS_PER_WORD
2694 || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2695 != (BYTES_BIG_ENDIAN ? upward : downward)))
2696 #endif
2699 rtx reg;
2701 /* We are really truncating a word_mode value containing
2702 SIZE bytes into a value of mode MODE. If such an
2703 operation requires no actual instructions, we can refer
2704 to the value directly in mode MODE, otherwise we must
2705 start with the register in word_mode and explicitly
2706 convert it. */
2707 if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2708 reg = gen_rtx_REG (mode, REGNO (entry_parm));
2709 else
2711 reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2712 reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2714 emit_move_insn (change_address (mem, mode, 0), reg);
2717 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2718 machine must be aligned to the left before storing
2719 to memory. Note that the previous test doesn't
2720 handle all cases (e.g. SIZE == 3). */
2721 else if (size != UNITS_PER_WORD
2722 #ifdef BLOCK_REG_PADDING
2723 && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2724 == downward)
2725 #else
2726 && BYTES_BIG_ENDIAN
2727 #endif
2730 rtx tem, x;
2731 int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2732 rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2734 x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2735 build_int_cst (NULL_TREE, by),
2736 NULL_RTX, 1);
2737 tem = change_address (mem, word_mode, 0);
2738 emit_move_insn (tem, x);
2740 else
2741 move_block_from_reg (REGNO (entry_parm), mem,
2742 size_stored / UNITS_PER_WORD);
2744 else
2745 move_block_from_reg (REGNO (entry_parm), mem,
2746 size_stored / UNITS_PER_WORD);
2748 else if (data->stack_parm == 0)
2750 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2751 emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2752 BLOCK_OP_NORMAL);
2753 all->first_conversion_insn = get_insns ();
2754 all->last_conversion_insn = get_last_insn ();
2755 end_sequence ();
2758 data->stack_parm = stack_parm;
2759 SET_DECL_RTL (parm, stack_parm);
2762 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2763 parameter. Get it there. Perform all ABI specified conversions. */
2765 static void
2766 assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2767 struct assign_parm_data_one *data)
2769 rtx parmreg;
2770 enum machine_mode promoted_nominal_mode;
2771 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2772 bool did_conversion = false;
2774 /* Store the parm in a pseudoregister during the function, but we may
2775 need to do it in a wider mode. */
2777 /* This is not really promoting for a call. However we need to be
2778 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2779 promoted_nominal_mode
2780 = promote_mode (data->nominal_type, data->nominal_mode, &unsignedp, 1);
2782 parmreg = gen_reg_rtx (promoted_nominal_mode);
2784 if (!DECL_ARTIFICIAL (parm))
2785 mark_user_reg (parmreg);
2787 /* If this was an item that we received a pointer to,
2788 set DECL_RTL appropriately. */
2789 if (data->passed_pointer)
2791 rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2792 set_mem_attributes (x, parm, 1);
2793 SET_DECL_RTL (parm, x);
2795 else
2796 SET_DECL_RTL (parm, parmreg);
2798 assign_parm_remove_parallels (data);
2800 /* Copy the value into the register. */
2801 if (data->nominal_mode != data->passed_mode
2802 || promoted_nominal_mode != data->promoted_mode)
2804 int save_tree_used;
2806 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2807 mode, by the caller. We now have to convert it to
2808 NOMINAL_MODE, if different. However, PARMREG may be in
2809 a different mode than NOMINAL_MODE if it is being stored
2810 promoted.
2812 If ENTRY_PARM is a hard register, it might be in a register
2813 not valid for operating in its mode (e.g., an odd-numbered
2814 register for a DFmode). In that case, moves are the only
2815 thing valid, so we can't do a convert from there. This
2816 occurs when the calling sequence allow such misaligned
2817 usages.
2819 In addition, the conversion may involve a call, which could
2820 clobber parameters which haven't been copied to pseudo
2821 registers yet. Therefore, we must first copy the parm to
2822 a pseudo reg here, and save the conversion until after all
2823 parameters have been moved. */
2825 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2827 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2829 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2830 tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2832 if (GET_CODE (tempreg) == SUBREG
2833 && GET_MODE (tempreg) == data->nominal_mode
2834 && REG_P (SUBREG_REG (tempreg))
2835 && data->nominal_mode == data->passed_mode
2836 && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2837 && GET_MODE_SIZE (GET_MODE (tempreg))
2838 < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2840 /* The argument is already sign/zero extended, so note it
2841 into the subreg. */
2842 SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2843 SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2846 /* TREE_USED gets set erroneously during expand_assignment. */
2847 save_tree_used = TREE_USED (parm);
2848 expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
2849 TREE_USED (parm) = save_tree_used;
2850 all->first_conversion_insn = get_insns ();
2851 all->last_conversion_insn = get_last_insn ();
2852 end_sequence ();
2854 did_conversion = true;
2856 else
2857 emit_move_insn (parmreg, validize_mem (data->entry_parm));
2859 /* If we were passed a pointer but the actual value can safely live
2860 in a register, put it in one. */
2861 if (data->passed_pointer
2862 && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2863 /* If by-reference argument was promoted, demote it. */
2864 && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2865 || use_register_for_decl (parm)))
2867 /* We can't use nominal_mode, because it will have been set to
2868 Pmode above. We must use the actual mode of the parm. */
2869 parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2870 mark_user_reg (parmreg);
2872 if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2874 rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2875 int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2877 push_to_sequence2 (all->first_conversion_insn,
2878 all->last_conversion_insn);
2879 emit_move_insn (tempreg, DECL_RTL (parm));
2880 tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2881 emit_move_insn (parmreg, tempreg);
2882 all->first_conversion_insn = get_insns ();
2883 all->last_conversion_insn = get_last_insn ();
2884 end_sequence ();
2886 did_conversion = true;
2888 else
2889 emit_move_insn (parmreg, DECL_RTL (parm));
2891 SET_DECL_RTL (parm, parmreg);
2893 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2894 now the parm. */
2895 data->stack_parm = NULL;
2898 /* Mark the register as eliminable if we did no conversion and it was
2899 copied from memory at a fixed offset, and the arg pointer was not
2900 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2901 offset formed an invalid address, such memory-equivalences as we
2902 make here would screw up life analysis for it. */
2903 if (data->nominal_mode == data->passed_mode
2904 && !did_conversion
2905 && data->stack_parm != 0
2906 && MEM_P (data->stack_parm)
2907 && data->locate.offset.var == 0
2908 && reg_mentioned_p (virtual_incoming_args_rtx,
2909 XEXP (data->stack_parm, 0)))
2911 rtx linsn = get_last_insn ();
2912 rtx sinsn, set;
2914 /* Mark complex types separately. */
2915 if (GET_CODE (parmreg) == CONCAT)
2917 enum machine_mode submode
2918 = GET_MODE_INNER (GET_MODE (parmreg));
2919 int regnor = REGNO (XEXP (parmreg, 0));
2920 int regnoi = REGNO (XEXP (parmreg, 1));
2921 rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
2922 rtx stacki = adjust_address_nv (data->stack_parm, submode,
2923 GET_MODE_SIZE (submode));
2925 /* Scan backwards for the set of the real and
2926 imaginary parts. */
2927 for (sinsn = linsn; sinsn != 0;
2928 sinsn = prev_nonnote_insn (sinsn))
2930 set = single_set (sinsn);
2931 if (set == 0)
2932 continue;
2934 if (SET_DEST (set) == regno_reg_rtx [regnoi])
2935 set_unique_reg_note (sinsn, REG_EQUIV, stacki);
2936 else if (SET_DEST (set) == regno_reg_rtx [regnor])
2937 set_unique_reg_note (sinsn, REG_EQUIV, stackr);
2940 else if ((set = single_set (linsn)) != 0
2941 && SET_DEST (set) == parmreg)
2942 set_unique_reg_note (linsn, REG_EQUIV, data->stack_parm);
2945 /* For pointer data type, suggest pointer register. */
2946 if (POINTER_TYPE_P (TREE_TYPE (parm)))
2947 mark_reg_pointer (parmreg,
2948 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
2951 /* A subroutine of assign_parms. Allocate stack space to hold the current
2952 parameter. Get it there. Perform all ABI specified conversions. */
2954 static void
2955 assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
2956 struct assign_parm_data_one *data)
2958 /* Value must be stored in the stack slot STACK_PARM during function
2959 execution. */
2960 bool to_conversion = false;
2962 assign_parm_remove_parallels (data);
2964 if (data->promoted_mode != data->nominal_mode)
2966 /* Conversion is required. */
2967 rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2969 emit_move_insn (tempreg, validize_mem (data->entry_parm));
2971 push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2972 to_conversion = true;
2974 data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
2975 TYPE_UNSIGNED (TREE_TYPE (parm)));
2977 if (data->stack_parm)
2978 /* ??? This may need a big-endian conversion on sparc64. */
2979 data->stack_parm
2980 = adjust_address (data->stack_parm, data->nominal_mode, 0);
2983 if (data->entry_parm != data->stack_parm)
2985 rtx src, dest;
2987 if (data->stack_parm == 0)
2989 int align = STACK_SLOT_ALIGNMENT (data->passed_type,
2990 GET_MODE (data->entry_parm),
2991 TYPE_ALIGN (data->passed_type));
2992 data->stack_parm
2993 = assign_stack_local (GET_MODE (data->entry_parm),
2994 GET_MODE_SIZE (GET_MODE (data->entry_parm)),
2995 align);
2996 set_mem_attributes (data->stack_parm, parm, 1);
2999 dest = validize_mem (data->stack_parm);
3000 src = validize_mem (data->entry_parm);
3002 if (MEM_P (src))
3004 /* Use a block move to handle potentially misaligned entry_parm. */
3005 if (!to_conversion)
3006 push_to_sequence2 (all->first_conversion_insn,
3007 all->last_conversion_insn);
3008 to_conversion = true;
3010 emit_block_move (dest, src,
3011 GEN_INT (int_size_in_bytes (data->passed_type)),
3012 BLOCK_OP_NORMAL);
3014 else
3015 emit_move_insn (dest, src);
3018 if (to_conversion)
3020 all->first_conversion_insn = get_insns ();
3021 all->last_conversion_insn = get_last_insn ();
3022 end_sequence ();
3025 SET_DECL_RTL (parm, data->stack_parm);
3028 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3029 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3031 static void
3032 assign_parms_unsplit_complex (struct assign_parm_data_all *all, tree fnargs)
3034 tree parm;
3035 tree orig_fnargs = all->orig_fnargs;
3037 for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm))
3039 if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3040 && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3042 rtx tmp, real, imag;
3043 enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3045 real = DECL_RTL (fnargs);
3046 imag = DECL_RTL (TREE_CHAIN (fnargs));
3047 if (inner != GET_MODE (real))
3049 real = gen_lowpart_SUBREG (inner, real);
3050 imag = gen_lowpart_SUBREG (inner, imag);
3053 if (TREE_ADDRESSABLE (parm))
3055 rtx rmem, imem;
3056 HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3057 int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3058 DECL_MODE (parm),
3059 TYPE_ALIGN (TREE_TYPE (parm)));
3061 /* split_complex_arg put the real and imag parts in
3062 pseudos. Move them to memory. */
3063 tmp = assign_stack_local (DECL_MODE (parm), size, align);
3064 set_mem_attributes (tmp, parm, 1);
3065 rmem = adjust_address_nv (tmp, inner, 0);
3066 imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3067 push_to_sequence2 (all->first_conversion_insn,
3068 all->last_conversion_insn);
3069 emit_move_insn (rmem, real);
3070 emit_move_insn (imem, imag);
3071 all->first_conversion_insn = get_insns ();
3072 all->last_conversion_insn = get_last_insn ();
3073 end_sequence ();
3075 else
3076 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3077 SET_DECL_RTL (parm, tmp);
3079 real = DECL_INCOMING_RTL (fnargs);
3080 imag = DECL_INCOMING_RTL (TREE_CHAIN (fnargs));
3081 if (inner != GET_MODE (real))
3083 real = gen_lowpart_SUBREG (inner, real);
3084 imag = gen_lowpart_SUBREG (inner, imag);
3086 tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3087 set_decl_incoming_rtl (parm, tmp, false);
3088 fnargs = TREE_CHAIN (fnargs);
3090 else
3092 SET_DECL_RTL (parm, DECL_RTL (fnargs));
3093 set_decl_incoming_rtl (parm, DECL_INCOMING_RTL (fnargs), false);
3095 /* Set MEM_EXPR to the original decl, i.e. to PARM,
3096 instead of the copy of decl, i.e. FNARGS. */
3097 if (DECL_INCOMING_RTL (parm) && MEM_P (DECL_INCOMING_RTL (parm)))
3098 set_mem_expr (DECL_INCOMING_RTL (parm), parm);
3101 fnargs = TREE_CHAIN (fnargs);
3105 /* Assign RTL expressions to the function's parameters. This may involve
3106 copying them into registers and using those registers as the DECL_RTL. */
3108 static void
3109 assign_parms (tree fndecl)
3111 struct assign_parm_data_all all;
3112 tree fnargs, parm;
3114 crtl->args.internal_arg_pointer
3115 = targetm.calls.internal_arg_pointer ();
3117 assign_parms_initialize_all (&all);
3118 fnargs = assign_parms_augmented_arg_list (&all);
3120 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3122 struct assign_parm_data_one data;
3124 /* Extract the type of PARM; adjust it according to ABI. */
3125 assign_parm_find_data_types (&all, parm, &data);
3127 /* Early out for errors and void parameters. */
3128 if (data.passed_mode == VOIDmode)
3130 SET_DECL_RTL (parm, const0_rtx);
3131 DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3132 continue;
3135 /* Estimate stack alignment from parameter alignment. */
3136 if (SUPPORTS_STACK_ALIGNMENT)
3138 unsigned int align = FUNCTION_ARG_BOUNDARY (data.promoted_mode,
3139 data.passed_type);
3140 if (TYPE_ALIGN (data.nominal_type) > align)
3141 align = TYPE_ALIGN (data.passed_type);
3142 if (crtl->stack_alignment_estimated < align)
3144 gcc_assert (!crtl->stack_realign_processed);
3145 crtl->stack_alignment_estimated = align;
3149 if (cfun->stdarg && !TREE_CHAIN (parm))
3150 assign_parms_setup_varargs (&all, &data, false);
3152 /* Find out where the parameter arrives in this function. */
3153 assign_parm_find_entry_rtl (&all, &data);
3155 /* Find out where stack space for this parameter might be. */
3156 if (assign_parm_is_stack_parm (&all, &data))
3158 assign_parm_find_stack_rtl (parm, &data);
3159 assign_parm_adjust_entry_rtl (&data);
3162 /* Record permanently how this parm was passed. */
3163 set_decl_incoming_rtl (parm, data.entry_parm, data.passed_pointer);
3165 /* Update info on where next arg arrives in registers. */
3166 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3167 data.passed_type, data.named_arg);
3169 assign_parm_adjust_stack_rtl (&data);
3171 if (assign_parm_setup_block_p (&data))
3172 assign_parm_setup_block (&all, parm, &data);
3173 else if (data.passed_pointer || use_register_for_decl (parm))
3174 assign_parm_setup_reg (&all, parm, &data);
3175 else
3176 assign_parm_setup_stack (&all, parm, &data);
3179 if (targetm.calls.split_complex_arg && fnargs != all.orig_fnargs)
3180 assign_parms_unsplit_complex (&all, fnargs);
3182 /* Output all parameter conversion instructions (possibly including calls)
3183 now that all parameters have been copied out of hard registers. */
3184 emit_insn (all.first_conversion_insn);
3186 /* Estimate reload stack alignment from scalar return mode. */
3187 if (SUPPORTS_STACK_ALIGNMENT)
3189 if (DECL_RESULT (fndecl))
3191 tree type = TREE_TYPE (DECL_RESULT (fndecl));
3192 enum machine_mode mode = TYPE_MODE (type);
3194 if (mode != BLKmode
3195 && mode != VOIDmode
3196 && !AGGREGATE_TYPE_P (type))
3198 unsigned int align = GET_MODE_ALIGNMENT (mode);
3199 if (crtl->stack_alignment_estimated < align)
3201 gcc_assert (!crtl->stack_realign_processed);
3202 crtl->stack_alignment_estimated = align;
3208 /* If we are receiving a struct value address as the first argument, set up
3209 the RTL for the function result. As this might require code to convert
3210 the transmitted address to Pmode, we do this here to ensure that possible
3211 preliminary conversions of the address have been emitted already. */
3212 if (all.function_result_decl)
3214 tree result = DECL_RESULT (current_function_decl);
3215 rtx addr = DECL_RTL (all.function_result_decl);
3216 rtx x;
3218 if (DECL_BY_REFERENCE (result))
3219 x = addr;
3220 else
3222 addr = convert_memory_address (Pmode, addr);
3223 x = gen_rtx_MEM (DECL_MODE (result), addr);
3224 set_mem_attributes (x, result, 1);
3226 SET_DECL_RTL (result, x);
3229 /* We have aligned all the args, so add space for the pretend args. */
3230 crtl->args.pretend_args_size = all.pretend_args_size;
3231 all.stack_args_size.constant += all.extra_pretend_bytes;
3232 crtl->args.size = all.stack_args_size.constant;
3234 /* Adjust function incoming argument size for alignment and
3235 minimum length. */
3237 #ifdef REG_PARM_STACK_SPACE
3238 crtl->args.size = MAX (crtl->args.size,
3239 REG_PARM_STACK_SPACE (fndecl));
3240 #endif
3242 crtl->args.size = CEIL_ROUND (crtl->args.size,
3243 PARM_BOUNDARY / BITS_PER_UNIT);
3245 #ifdef ARGS_GROW_DOWNWARD
3246 crtl->args.arg_offset_rtx
3247 = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3248 : expand_expr (size_diffop (all.stack_args_size.var,
3249 size_int (-all.stack_args_size.constant)),
3250 NULL_RTX, VOIDmode, EXPAND_NORMAL));
3251 #else
3252 crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3253 #endif
3255 /* See how many bytes, if any, of its args a function should try to pop
3256 on return. */
3258 crtl->args.pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
3259 crtl->args.size);
3261 /* For stdarg.h function, save info about
3262 regs and stack space used by the named args. */
3264 crtl->args.info = all.args_so_far;
3266 /* Set the rtx used for the function return value. Put this in its
3267 own variable so any optimizers that need this information don't have
3268 to include tree.h. Do this here so it gets done when an inlined
3269 function gets output. */
3271 crtl->return_rtx
3272 = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3273 ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3275 /* If scalar return value was computed in a pseudo-reg, or was a named
3276 return value that got dumped to the stack, copy that to the hard
3277 return register. */
3278 if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3280 tree decl_result = DECL_RESULT (fndecl);
3281 rtx decl_rtl = DECL_RTL (decl_result);
3283 if (REG_P (decl_rtl)
3284 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3285 : DECL_REGISTER (decl_result))
3287 rtx real_decl_rtl;
3289 real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3290 fndecl, true);
3291 REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3292 /* The delay slot scheduler assumes that crtl->return_rtx
3293 holds the hard register containing the return value, not a
3294 temporary pseudo. */
3295 crtl->return_rtx = real_decl_rtl;
3300 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3301 For all seen types, gimplify their sizes. */
3303 static tree
3304 gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3306 tree t = *tp;
3308 *walk_subtrees = 0;
3309 if (TYPE_P (t))
3311 if (POINTER_TYPE_P (t))
3312 *walk_subtrees = 1;
3313 else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3314 && !TYPE_SIZES_GIMPLIFIED (t))
3316 gimplify_type_sizes (t, (gimple_seq *) data);
3317 *walk_subtrees = 1;
3321 return NULL;
3324 /* Gimplify the parameter list for current_function_decl. This involves
3325 evaluating SAVE_EXPRs of variable sized parameters and generating code
3326 to implement callee-copies reference parameters. Returns a sequence of
3327 statements to add to the beginning of the function. */
3329 gimple_seq
3330 gimplify_parameters (void)
3332 struct assign_parm_data_all all;
3333 tree fnargs, parm;
3334 gimple_seq stmts = NULL;
3336 assign_parms_initialize_all (&all);
3337 fnargs = assign_parms_augmented_arg_list (&all);
3339 for (parm = fnargs; parm; parm = TREE_CHAIN (parm))
3341 struct assign_parm_data_one data;
3343 /* Extract the type of PARM; adjust it according to ABI. */
3344 assign_parm_find_data_types (&all, parm, &data);
3346 /* Early out for errors and void parameters. */
3347 if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3348 continue;
3350 /* Update info on where next arg arrives in registers. */
3351 FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3352 data.passed_type, data.named_arg);
3354 /* ??? Once upon a time variable_size stuffed parameter list
3355 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3356 turned out to be less than manageable in the gimple world.
3357 Now we have to hunt them down ourselves. */
3358 walk_tree_without_duplicates (&data.passed_type,
3359 gimplify_parm_type, &stmts);
3361 if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3363 gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3364 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3367 if (data.passed_pointer)
3369 tree type = TREE_TYPE (data.passed_type);
3370 if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3371 type, data.named_arg))
3373 tree local, t;
3375 /* For constant-sized objects, this is trivial; for
3376 variable-sized objects, we have to play games. */
3377 if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3378 && !(flag_stack_check == GENERIC_STACK_CHECK
3379 && compare_tree_int (DECL_SIZE_UNIT (parm),
3380 STACK_CHECK_MAX_VAR_SIZE) > 0))
3382 local = create_tmp_var (type, get_name (parm));
3383 DECL_IGNORED_P (local) = 0;
3384 /* If PARM was addressable, move that flag over
3385 to the local copy, as its address will be taken,
3386 not the PARMs. */
3387 if (TREE_ADDRESSABLE (parm))
3389 TREE_ADDRESSABLE (parm) = 0;
3390 TREE_ADDRESSABLE (local) = 1;
3393 else
3395 tree ptr_type, addr;
3397 ptr_type = build_pointer_type (type);
3398 addr = create_tmp_var (ptr_type, get_name (parm));
3399 DECL_IGNORED_P (addr) = 0;
3400 local = build_fold_indirect_ref (addr);
3402 t = built_in_decls[BUILT_IN_ALLOCA];
3403 t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3404 t = fold_convert (ptr_type, t);
3405 t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3406 gimplify_and_add (t, &stmts);
3409 gimplify_assign (local, parm, &stmts);
3411 SET_DECL_VALUE_EXPR (parm, local);
3412 DECL_HAS_VALUE_EXPR_P (parm) = 1;
3417 return stmts;
3420 /* Compute the size and offset from the start of the stacked arguments for a
3421 parm passed in mode PASSED_MODE and with type TYPE.
3423 INITIAL_OFFSET_PTR points to the current offset into the stacked
3424 arguments.
3426 The starting offset and size for this parm are returned in
3427 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3428 nonzero, the offset is that of stack slot, which is returned in
3429 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3430 padding required from the initial offset ptr to the stack slot.
3432 IN_REGS is nonzero if the argument will be passed in registers. It will
3433 never be set if REG_PARM_STACK_SPACE is not defined.
3435 FNDECL is the function in which the argument was defined.
3437 There are two types of rounding that are done. The first, controlled by
3438 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3439 list to be aligned to the specific boundary (in bits). This rounding
3440 affects the initial and starting offsets, but not the argument size.
3442 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3443 optionally rounds the size of the parm to PARM_BOUNDARY. The
3444 initial offset is not affected by this rounding, while the size always
3445 is and the starting offset may be. */
3447 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3448 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3449 callers pass in the total size of args so far as
3450 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3452 void
3453 locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3454 int partial, tree fndecl ATTRIBUTE_UNUSED,
3455 struct args_size *initial_offset_ptr,
3456 struct locate_and_pad_arg_data *locate)
3458 tree sizetree;
3459 enum direction where_pad;
3460 unsigned int boundary;
3461 int reg_parm_stack_space = 0;
3462 int part_size_in_regs;
3464 #ifdef REG_PARM_STACK_SPACE
3465 reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3467 /* If we have found a stack parm before we reach the end of the
3468 area reserved for registers, skip that area. */
3469 if (! in_regs)
3471 if (reg_parm_stack_space > 0)
3473 if (initial_offset_ptr->var)
3475 initial_offset_ptr->var
3476 = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3477 ssize_int (reg_parm_stack_space));
3478 initial_offset_ptr->constant = 0;
3480 else if (initial_offset_ptr->constant < reg_parm_stack_space)
3481 initial_offset_ptr->constant = reg_parm_stack_space;
3484 #endif /* REG_PARM_STACK_SPACE */
3486 part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3488 sizetree
3489 = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3490 where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3491 boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3492 locate->where_pad = where_pad;
3494 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3495 if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3496 boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3498 locate->boundary = boundary;
3500 if (SUPPORTS_STACK_ALIGNMENT)
3502 /* stack_alignment_estimated can't change after stack has been
3503 realigned. */
3504 if (crtl->stack_alignment_estimated < boundary)
3506 if (!crtl->stack_realign_processed)
3507 crtl->stack_alignment_estimated = boundary;
3508 else
3510 /* If stack is realigned and stack alignment value
3511 hasn't been finalized, it is OK not to increase
3512 stack_alignment_estimated. The bigger alignment
3513 requirement is recorded in stack_alignment_needed
3514 below. */
3515 gcc_assert (!crtl->stack_realign_finalized
3516 && crtl->stack_realign_needed);
3521 /* Remember if the outgoing parameter requires extra alignment on the
3522 calling function side. */
3523 if (crtl->stack_alignment_needed < boundary)
3524 crtl->stack_alignment_needed = boundary;
3525 if (crtl->preferred_stack_boundary < boundary)
3526 crtl->preferred_stack_boundary = boundary;
3528 #ifdef ARGS_GROW_DOWNWARD
3529 locate->slot_offset.constant = -initial_offset_ptr->constant;
3530 if (initial_offset_ptr->var)
3531 locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3532 initial_offset_ptr->var);
3535 tree s2 = sizetree;
3536 if (where_pad != none
3537 && (!host_integerp (sizetree, 1)
3538 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3539 s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3540 SUB_PARM_SIZE (locate->slot_offset, s2);
3543 locate->slot_offset.constant += part_size_in_regs;
3545 if (!in_regs
3546 #ifdef REG_PARM_STACK_SPACE
3547 || REG_PARM_STACK_SPACE (fndecl) > 0
3548 #endif
3550 pad_to_arg_alignment (&locate->slot_offset, boundary,
3551 &locate->alignment_pad);
3553 locate->size.constant = (-initial_offset_ptr->constant
3554 - locate->slot_offset.constant);
3555 if (initial_offset_ptr->var)
3556 locate->size.var = size_binop (MINUS_EXPR,
3557 size_binop (MINUS_EXPR,
3558 ssize_int (0),
3559 initial_offset_ptr->var),
3560 locate->slot_offset.var);
3562 /* Pad_below needs the pre-rounded size to know how much to pad
3563 below. */
3564 locate->offset = locate->slot_offset;
3565 if (where_pad == downward)
3566 pad_below (&locate->offset, passed_mode, sizetree);
3568 #else /* !ARGS_GROW_DOWNWARD */
3569 if (!in_regs
3570 #ifdef REG_PARM_STACK_SPACE
3571 || REG_PARM_STACK_SPACE (fndecl) > 0
3572 #endif
3574 pad_to_arg_alignment (initial_offset_ptr, boundary,
3575 &locate->alignment_pad);
3576 locate->slot_offset = *initial_offset_ptr;
3578 #ifdef PUSH_ROUNDING
3579 if (passed_mode != BLKmode)
3580 sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3581 #endif
3583 /* Pad_below needs the pre-rounded size to know how much to pad below
3584 so this must be done before rounding up. */
3585 locate->offset = locate->slot_offset;
3586 if (where_pad == downward)
3587 pad_below (&locate->offset, passed_mode, sizetree);
3589 if (where_pad != none
3590 && (!host_integerp (sizetree, 1)
3591 || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3592 sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3594 ADD_PARM_SIZE (locate->size, sizetree);
3596 locate->size.constant -= part_size_in_regs;
3597 #endif /* ARGS_GROW_DOWNWARD */
3599 #ifdef FUNCTION_ARG_OFFSET
3600 locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3601 #endif
3604 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3605 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3607 static void
3608 pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3609 struct args_size *alignment_pad)
3611 tree save_var = NULL_TREE;
3612 HOST_WIDE_INT save_constant = 0;
3613 int boundary_in_bytes = boundary / BITS_PER_UNIT;
3614 HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3616 #ifdef SPARC_STACK_BOUNDARY_HACK
3617 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3618 the real alignment of %sp. However, when it does this, the
3619 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3620 if (SPARC_STACK_BOUNDARY_HACK)
3621 sp_offset = 0;
3622 #endif
3624 if (boundary > PARM_BOUNDARY)
3626 save_var = offset_ptr->var;
3627 save_constant = offset_ptr->constant;
3630 alignment_pad->var = NULL_TREE;
3631 alignment_pad->constant = 0;
3633 if (boundary > BITS_PER_UNIT)
3635 if (offset_ptr->var)
3637 tree sp_offset_tree = ssize_int (sp_offset);
3638 tree offset = size_binop (PLUS_EXPR,
3639 ARGS_SIZE_TREE (*offset_ptr),
3640 sp_offset_tree);
3641 #ifdef ARGS_GROW_DOWNWARD
3642 tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3643 #else
3644 tree rounded = round_up (offset, boundary / BITS_PER_UNIT);
3645 #endif
3647 offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3648 /* ARGS_SIZE_TREE includes constant term. */
3649 offset_ptr->constant = 0;
3650 if (boundary > PARM_BOUNDARY)
3651 alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3652 save_var);
3654 else
3656 offset_ptr->constant = -sp_offset +
3657 #ifdef ARGS_GROW_DOWNWARD
3658 FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3659 #else
3660 CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3661 #endif
3662 if (boundary > PARM_BOUNDARY)
3663 alignment_pad->constant = offset_ptr->constant - save_constant;
3668 static void
3669 pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3671 if (passed_mode != BLKmode)
3673 if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3674 offset_ptr->constant
3675 += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3676 / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3677 - GET_MODE_SIZE (passed_mode));
3679 else
3681 if (TREE_CODE (sizetree) != INTEGER_CST
3682 || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3684 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3685 tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3686 /* Add it in. */
3687 ADD_PARM_SIZE (*offset_ptr, s2);
3688 SUB_PARM_SIZE (*offset_ptr, sizetree);
3694 /* True if register REGNO was alive at a place where `setjmp' was
3695 called and was set more than once or is an argument. Such regs may
3696 be clobbered by `longjmp'. */
3698 static bool
3699 regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3701 /* There appear to be cases where some local vars never reach the
3702 backend but have bogus regnos. */
3703 if (regno >= max_reg_num ())
3704 return false;
3706 return ((REG_N_SETS (regno) > 1
3707 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3708 && REGNO_REG_SET_P (setjmp_crosses, regno));
3711 /* Walk the tree of blocks describing the binding levels within a
3712 function and warn about variables the might be killed by setjmp or
3713 vfork. This is done after calling flow_analysis before register
3714 allocation since that will clobber the pseudo-regs to hard
3715 regs. */
3717 static void
3718 setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3720 tree decl, sub;
3722 for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3724 if (TREE_CODE (decl) == VAR_DECL
3725 && DECL_RTL_SET_P (decl)
3726 && REG_P (DECL_RTL (decl))
3727 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3728 warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3729 " %<longjmp%> or %<vfork%>", decl);
3732 for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3733 setjmp_vars_warning (setjmp_crosses, sub);
3736 /* Do the appropriate part of setjmp_vars_warning
3737 but for arguments instead of local variables. */
3739 static void
3740 setjmp_args_warning (bitmap setjmp_crosses)
3742 tree decl;
3743 for (decl = DECL_ARGUMENTS (current_function_decl);
3744 decl; decl = TREE_CHAIN (decl))
3745 if (DECL_RTL (decl) != 0
3746 && REG_P (DECL_RTL (decl))
3747 && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3748 warning (OPT_Wclobbered,
3749 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3750 decl);
3753 /* Generate warning messages for variables live across setjmp. */
3755 void
3756 generate_setjmp_warnings (void)
3758 bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3760 if (n_basic_blocks == NUM_FIXED_BLOCKS
3761 || bitmap_empty_p (setjmp_crosses))
3762 return;
3764 setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3765 setjmp_args_warning (setjmp_crosses);
3769 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3770 and create duplicate blocks. */
3771 /* ??? Need an option to either create block fragments or to create
3772 abstract origin duplicates of a source block. It really depends
3773 on what optimization has been performed. */
3775 void
3776 reorder_blocks (void)
3778 tree block = DECL_INITIAL (current_function_decl);
3779 VEC(tree,heap) *block_stack;
3781 if (block == NULL_TREE)
3782 return;
3784 block_stack = VEC_alloc (tree, heap, 10);
3786 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3787 clear_block_marks (block);
3789 /* Prune the old trees away, so that they don't get in the way. */
3790 BLOCK_SUBBLOCKS (block) = NULL_TREE;
3791 BLOCK_CHAIN (block) = NULL_TREE;
3793 /* Recreate the block tree from the note nesting. */
3794 reorder_blocks_1 (get_insns (), block, &block_stack);
3795 BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3797 VEC_free (tree, heap, block_stack);
3800 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3802 void
3803 clear_block_marks (tree block)
3805 while (block)
3807 TREE_ASM_WRITTEN (block) = 0;
3808 clear_block_marks (BLOCK_SUBBLOCKS (block));
3809 block = BLOCK_CHAIN (block);
3813 static void
3814 reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3816 rtx insn;
3818 for (insn = insns; insn; insn = NEXT_INSN (insn))
3820 if (NOTE_P (insn))
3822 if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
3824 tree block = NOTE_BLOCK (insn);
3825 tree origin;
3827 origin = (BLOCK_FRAGMENT_ORIGIN (block)
3828 ? BLOCK_FRAGMENT_ORIGIN (block)
3829 : block);
3831 /* If we have seen this block before, that means it now
3832 spans multiple address regions. Create a new fragment. */
3833 if (TREE_ASM_WRITTEN (block))
3835 tree new_block = copy_node (block);
3837 BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3838 BLOCK_FRAGMENT_CHAIN (new_block)
3839 = BLOCK_FRAGMENT_CHAIN (origin);
3840 BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3842 NOTE_BLOCK (insn) = new_block;
3843 block = new_block;
3846 BLOCK_SUBBLOCKS (block) = 0;
3847 TREE_ASM_WRITTEN (block) = 1;
3848 /* When there's only one block for the entire function,
3849 current_block == block and we mustn't do this, it
3850 will cause infinite recursion. */
3851 if (block != current_block)
3853 if (block != origin)
3854 gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
3856 BLOCK_SUPERCONTEXT (block) = current_block;
3857 BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3858 BLOCK_SUBBLOCKS (current_block) = block;
3859 current_block = origin;
3861 VEC_safe_push (tree, heap, *p_block_stack, block);
3863 else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
3865 NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3866 BLOCK_SUBBLOCKS (current_block)
3867 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3868 current_block = BLOCK_SUPERCONTEXT (current_block);
3874 /* Reverse the order of elements in the chain T of blocks,
3875 and return the new head of the chain (old last element). */
3877 tree
3878 blocks_nreverse (tree t)
3880 tree prev = 0, decl, next;
3881 for (decl = t; decl; decl = next)
3883 next = BLOCK_CHAIN (decl);
3884 BLOCK_CHAIN (decl) = prev;
3885 prev = decl;
3887 return prev;
3890 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3891 non-NULL, list them all into VECTOR, in a depth-first preorder
3892 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3893 blocks. */
3895 static int
3896 all_blocks (tree block, tree *vector)
3898 int n_blocks = 0;
3900 while (block)
3902 TREE_ASM_WRITTEN (block) = 0;
3904 /* Record this block. */
3905 if (vector)
3906 vector[n_blocks] = block;
3908 ++n_blocks;
3910 /* Record the subblocks, and their subblocks... */
3911 n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3912 vector ? vector + n_blocks : 0);
3913 block = BLOCK_CHAIN (block);
3916 return n_blocks;
3919 /* Return a vector containing all the blocks rooted at BLOCK. The
3920 number of elements in the vector is stored in N_BLOCKS_P. The
3921 vector is dynamically allocated; it is the caller's responsibility
3922 to call `free' on the pointer returned. */
3924 static tree *
3925 get_block_vector (tree block, int *n_blocks_p)
3927 tree *block_vector;
3929 *n_blocks_p = all_blocks (block, NULL);
3930 block_vector = XNEWVEC (tree, *n_blocks_p);
3931 all_blocks (block, block_vector);
3933 return block_vector;
3936 static GTY(()) int next_block_index = 2;
3938 /* Set BLOCK_NUMBER for all the blocks in FN. */
3940 void
3941 number_blocks (tree fn)
3943 int i;
3944 int n_blocks;
3945 tree *block_vector;
3947 /* For SDB and XCOFF debugging output, we start numbering the blocks
3948 from 1 within each function, rather than keeping a running
3949 count. */
3950 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3951 if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3952 next_block_index = 1;
3953 #endif
3955 block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3957 /* The top-level BLOCK isn't numbered at all. */
3958 for (i = 1; i < n_blocks; ++i)
3959 /* We number the blocks from two. */
3960 BLOCK_NUMBER (block_vector[i]) = next_block_index++;
3962 free (block_vector);
3964 return;
3967 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3969 tree
3970 debug_find_var_in_block_tree (tree var, tree block)
3972 tree t;
3974 for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
3975 if (t == var)
3976 return block;
3978 for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
3980 tree ret = debug_find_var_in_block_tree (var, t);
3981 if (ret)
3982 return ret;
3985 return NULL_TREE;
3988 /* Keep track of whether we're in a dummy function context. If we are,
3989 we don't want to invoke the set_current_function hook, because we'll
3990 get into trouble if the hook calls target_reinit () recursively or
3991 when the initial initialization is not yet complete. */
3993 static bool in_dummy_function;
3995 /* Invoke the target hook when setting cfun. Update the optimization options
3996 if the function uses different options than the default. */
3998 static void
3999 invoke_set_current_function_hook (tree fndecl)
4001 if (!in_dummy_function)
4003 tree opts = ((fndecl)
4004 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4005 : optimization_default_node);
4007 if (!opts)
4008 opts = optimization_default_node;
4010 /* Change optimization options if needed. */
4011 if (optimization_current_node != opts)
4013 optimization_current_node = opts;
4014 cl_optimization_restore (TREE_OPTIMIZATION (opts));
4017 targetm.set_current_function (fndecl);
4021 /* cfun should never be set directly; use this function. */
4023 void
4024 set_cfun (struct function *new_cfun)
4026 if (cfun != new_cfun)
4028 cfun = new_cfun;
4029 invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4033 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4035 static VEC(function_p,heap) *cfun_stack;
4037 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4039 void
4040 push_cfun (struct function *new_cfun)
4042 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4043 set_cfun (new_cfun);
4046 /* Pop cfun from the stack. */
4048 void
4049 pop_cfun (void)
4051 struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4052 set_cfun (new_cfun);
4055 /* Return value of funcdef and increase it. */
4057 get_next_funcdef_no (void)
4059 return funcdef_no++;
4062 /* Allocate a function structure for FNDECL and set its contents
4063 to the defaults. Set cfun to the newly-allocated object.
4064 Some of the helper functions invoked during initialization assume
4065 that cfun has already been set. Therefore, assign the new object
4066 directly into cfun and invoke the back end hook explicitly at the
4067 very end, rather than initializing a temporary and calling set_cfun
4068 on it.
4070 ABSTRACT_P is true if this is a function that will never be seen by
4071 the middle-end. Such functions are front-end concepts (like C++
4072 function templates) that do not correspond directly to functions
4073 placed in object files. */
4075 void
4076 allocate_struct_function (tree fndecl, bool abstract_p)
4078 tree result;
4079 tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4081 cfun = GGC_CNEW (struct function);
4083 cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
4085 init_eh_for_function ();
4087 if (init_machine_status)
4088 cfun->machine = (*init_machine_status) ();
4090 #ifdef OVERRIDE_ABI_FORMAT
4091 OVERRIDE_ABI_FORMAT (fndecl);
4092 #endif
4094 invoke_set_current_function_hook (fndecl);
4096 if (fndecl != NULL_TREE)
4098 DECL_STRUCT_FUNCTION (fndecl) = cfun;
4099 cfun->decl = fndecl;
4100 current_function_funcdef_no = get_next_funcdef_no ();
4102 result = DECL_RESULT (fndecl);
4103 if (!abstract_p && aggregate_value_p (result, fndecl))
4105 #ifdef PCC_STATIC_STRUCT_RETURN
4106 cfun->returns_pcc_struct = 1;
4107 #endif
4108 cfun->returns_struct = 1;
4111 cfun->stdarg
4112 = (fntype
4113 && TYPE_ARG_TYPES (fntype) != 0
4114 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4115 != void_type_node));
4117 /* Assume all registers in stdarg functions need to be saved. */
4118 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4119 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4123 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4124 instead of just setting it. */
4126 void
4127 push_struct_function (tree fndecl)
4129 VEC_safe_push (function_p, heap, cfun_stack, cfun);
4130 allocate_struct_function (fndecl, false);
4133 /* Reset cfun, and other non-struct-function variables to defaults as
4134 appropriate for emitting rtl at the start of a function. */
4136 static void
4137 prepare_function_start (void)
4139 gcc_assert (!crtl->emit.x_last_insn);
4140 init_temp_slots ();
4141 init_emit ();
4142 init_varasm_status ();
4143 init_expr ();
4144 default_rtl_profile ();
4146 cse_not_expected = ! optimize;
4148 /* Caller save not needed yet. */
4149 caller_save_needed = 0;
4151 /* We haven't done register allocation yet. */
4152 reg_renumber = 0;
4154 /* Indicate that we have not instantiated virtual registers yet. */
4155 virtuals_instantiated = 0;
4157 /* Indicate that we want CONCATs now. */
4158 generating_concat_p = 1;
4160 /* Indicate we have no need of a frame pointer yet. */
4161 frame_pointer_needed = 0;
4164 /* Initialize the rtl expansion mechanism so that we can do simple things
4165 like generate sequences. This is used to provide a context during global
4166 initialization of some passes. You must call expand_dummy_function_end
4167 to exit this context. */
4169 void
4170 init_dummy_function_start (void)
4172 gcc_assert (!in_dummy_function);
4173 in_dummy_function = true;
4174 push_struct_function (NULL_TREE);
4175 prepare_function_start ();
4178 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4179 and initialize static variables for generating RTL for the statements
4180 of the function. */
4182 void
4183 init_function_start (tree subr)
4185 if (subr && DECL_STRUCT_FUNCTION (subr))
4186 set_cfun (DECL_STRUCT_FUNCTION (subr));
4187 else
4188 allocate_struct_function (subr, false);
4189 prepare_function_start ();
4191 /* Warn if this value is an aggregate type,
4192 regardless of which calling convention we are using for it. */
4193 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4194 warning (OPT_Waggregate_return, "function returns an aggregate");
4197 /* Make sure all values used by the optimization passes have sane defaults. */
4198 unsigned int
4199 init_function_for_compilation (void)
4201 reg_renumber = 0;
4202 return 0;
4205 struct rtl_opt_pass pass_init_function =
4208 RTL_PASS,
4209 NULL, /* name */
4210 NULL, /* gate */
4211 init_function_for_compilation, /* execute */
4212 NULL, /* sub */
4213 NULL, /* next */
4214 0, /* static_pass_number */
4215 TV_NONE, /* tv_id */
4216 0, /* properties_required */
4217 0, /* properties_provided */
4218 0, /* properties_destroyed */
4219 0, /* todo_flags_start */
4220 0 /* todo_flags_finish */
4225 void
4226 expand_main_function (void)
4228 #if (defined(INVOKE__main) \
4229 || (!defined(HAS_INIT_SECTION) \
4230 && !defined(INIT_SECTION_ASM_OP) \
4231 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4232 emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4233 #endif
4236 /* Expand code to initialize the stack_protect_guard. This is invoked at
4237 the beginning of a function to be protected. */
4239 #ifndef HAVE_stack_protect_set
4240 # define HAVE_stack_protect_set 0
4241 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4242 #endif
4244 void
4245 stack_protect_prologue (void)
4247 tree guard_decl = targetm.stack_protect_guard ();
4248 rtx x, y;
4250 /* Avoid expand_expr here, because we don't want guard_decl pulled
4251 into registers unless absolutely necessary. And we know that
4252 crtl->stack_protect_guard is a local stack slot, so this skips
4253 all the fluff. */
4254 x = validize_mem (DECL_RTL (crtl->stack_protect_guard));
4255 y = validize_mem (DECL_RTL (guard_decl));
4257 /* Allow the target to copy from Y to X without leaking Y into a
4258 register. */
4259 if (HAVE_stack_protect_set)
4261 rtx insn = gen_stack_protect_set (x, y);
4262 if (insn)
4264 emit_insn (insn);
4265 return;
4269 /* Otherwise do a straight move. */
4270 emit_move_insn (x, y);
4273 /* Expand code to verify the stack_protect_guard. This is invoked at
4274 the end of a function to be protected. */
4276 #ifndef HAVE_stack_protect_test
4277 # define HAVE_stack_protect_test 0
4278 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4279 #endif
4281 void
4282 stack_protect_epilogue (void)
4284 tree guard_decl = targetm.stack_protect_guard ();
4285 rtx label = gen_label_rtx ();
4286 rtx x, y, tmp;
4288 /* Avoid expand_expr here, because we don't want guard_decl pulled
4289 into registers unless absolutely necessary. And we know that
4290 crtl->stack_protect_guard is a local stack slot, so this skips
4291 all the fluff. */
4292 x = validize_mem (DECL_RTL (crtl->stack_protect_guard));
4293 y = validize_mem (DECL_RTL (guard_decl));
4295 /* Allow the target to compare Y with X without leaking either into
4296 a register. */
4297 switch (HAVE_stack_protect_test != 0)
4299 case 1:
4300 tmp = gen_stack_protect_test (x, y, label);
4301 if (tmp)
4303 emit_insn (tmp);
4304 break;
4306 /* FALLTHRU */
4308 default:
4309 emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4310 break;
4313 /* The noreturn predictor has been moved to the tree level. The rtl-level
4314 predictors estimate this branch about 20%, which isn't enough to get
4315 things moved out of line. Since this is the only extant case of adding
4316 a noreturn function at the rtl level, it doesn't seem worth doing ought
4317 except adding the prediction by hand. */
4318 tmp = get_last_insn ();
4319 if (JUMP_P (tmp))
4320 predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4322 expand_expr_stmt (targetm.stack_protect_fail ());
4323 emit_label (label);
4326 /* Start the RTL for a new function, and set variables used for
4327 emitting RTL.
4328 SUBR is the FUNCTION_DECL node.
4329 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4330 the function's parameters, which must be run at any return statement. */
4332 void
4333 expand_function_start (tree subr)
4335 /* Make sure volatile mem refs aren't considered
4336 valid operands of arithmetic insns. */
4337 init_recog_no_volatile ();
4339 crtl->profile
4340 = (profile_flag
4341 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4343 crtl->limit_stack
4344 = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4346 /* Make the label for return statements to jump to. Do not special
4347 case machines with special return instructions -- they will be
4348 handled later during jump, ifcvt, or epilogue creation. */
4349 return_label = gen_label_rtx ();
4351 /* Initialize rtx used to return the value. */
4352 /* Do this before assign_parms so that we copy the struct value address
4353 before any library calls that assign parms might generate. */
4355 /* Decide whether to return the value in memory or in a register. */
4356 if (aggregate_value_p (DECL_RESULT (subr), subr))
4358 /* Returning something that won't go in a register. */
4359 rtx value_address = 0;
4361 #ifdef PCC_STATIC_STRUCT_RETURN
4362 if (cfun->returns_pcc_struct)
4364 int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4365 value_address = assemble_static_space (size);
4367 else
4368 #endif
4370 rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4371 /* Expect to be passed the address of a place to store the value.
4372 If it is passed as an argument, assign_parms will take care of
4373 it. */
4374 if (sv)
4376 value_address = gen_reg_rtx (Pmode);
4377 emit_move_insn (value_address, sv);
4380 if (value_address)
4382 rtx x = value_address;
4383 if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4385 x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4386 set_mem_attributes (x, DECL_RESULT (subr), 1);
4388 SET_DECL_RTL (DECL_RESULT (subr), x);
4391 else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4392 /* If return mode is void, this decl rtl should not be used. */
4393 SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4394 else
4396 /* Compute the return values into a pseudo reg, which we will copy
4397 into the true return register after the cleanups are done. */
4398 tree return_type = TREE_TYPE (DECL_RESULT (subr));
4399 if (TYPE_MODE (return_type) != BLKmode
4400 && targetm.calls.return_in_msb (return_type))
4401 /* expand_function_end will insert the appropriate padding in
4402 this case. Use the return value's natural (unpadded) mode
4403 within the function proper. */
4404 SET_DECL_RTL (DECL_RESULT (subr),
4405 gen_reg_rtx (TYPE_MODE (return_type)));
4406 else
4408 /* In order to figure out what mode to use for the pseudo, we
4409 figure out what the mode of the eventual return register will
4410 actually be, and use that. */
4411 rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4413 /* Structures that are returned in registers are not
4414 aggregate_value_p, so we may see a PARALLEL or a REG. */
4415 if (REG_P (hard_reg))
4416 SET_DECL_RTL (DECL_RESULT (subr),
4417 gen_reg_rtx (GET_MODE (hard_reg)));
4418 else
4420 gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4421 SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4425 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4426 result to the real return register(s). */
4427 DECL_REGISTER (DECL_RESULT (subr)) = 1;
4430 /* Initialize rtx for parameters and local variables.
4431 In some cases this requires emitting insns. */
4432 assign_parms (subr);
4434 /* If function gets a static chain arg, store it. */
4435 if (cfun->static_chain_decl)
4437 tree parm = cfun->static_chain_decl;
4438 rtx local = gen_reg_rtx (Pmode);
4440 set_decl_incoming_rtl (parm, static_chain_incoming_rtx, false);
4441 SET_DECL_RTL (parm, local);
4442 mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4444 emit_move_insn (local, static_chain_incoming_rtx);
4447 /* If the function receives a non-local goto, then store the
4448 bits we need to restore the frame pointer. */
4449 if (cfun->nonlocal_goto_save_area)
4451 tree t_save;
4452 rtx r_save;
4454 /* ??? We need to do this save early. Unfortunately here is
4455 before the frame variable gets declared. Help out... */
4456 tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4457 if (!DECL_RTL_SET_P (var))
4458 expand_decl (var);
4460 t_save = build4 (ARRAY_REF, ptr_type_node,
4461 cfun->nonlocal_goto_save_area,
4462 integer_zero_node, NULL_TREE, NULL_TREE);
4463 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4464 r_save = convert_memory_address (Pmode, r_save);
4466 emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4467 update_nonlocal_goto_save_area ();
4470 /* The following was moved from init_function_start.
4471 The move is supposed to make sdb output more accurate. */
4472 /* Indicate the beginning of the function body,
4473 as opposed to parm setup. */
4474 emit_note (NOTE_INSN_FUNCTION_BEG);
4476 gcc_assert (NOTE_P (get_last_insn ()));
4478 parm_birth_insn = get_last_insn ();
4480 if (crtl->profile)
4482 #ifdef PROFILE_HOOK
4483 PROFILE_HOOK (current_function_funcdef_no);
4484 #endif
4487 /* After the display initializations is where the stack checking
4488 probe should go. */
4489 if(flag_stack_check)
4490 stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4492 /* Make sure there is a line number after the function entry setup code. */
4493 force_next_line_note ();
4496 /* Undo the effects of init_dummy_function_start. */
4497 void
4498 expand_dummy_function_end (void)
4500 gcc_assert (in_dummy_function);
4502 /* End any sequences that failed to be closed due to syntax errors. */
4503 while (in_sequence_p ())
4504 end_sequence ();
4506 /* Outside function body, can't compute type's actual size
4507 until next function's body starts. */
4509 free_after_parsing (cfun);
4510 free_after_compilation (cfun);
4511 pop_cfun ();
4512 in_dummy_function = false;
4515 /* Call DOIT for each hard register used as a return value from
4516 the current function. */
4518 void
4519 diddle_return_value (void (*doit) (rtx, void *), void *arg)
4521 rtx outgoing = crtl->return_rtx;
4523 if (! outgoing)
4524 return;
4526 if (REG_P (outgoing))
4527 (*doit) (outgoing, arg);
4528 else if (GET_CODE (outgoing) == PARALLEL)
4530 int i;
4532 for (i = 0; i < XVECLEN (outgoing, 0); i++)
4534 rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4536 if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4537 (*doit) (x, arg);
4542 static void
4543 do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4545 emit_clobber (reg);
4548 void
4549 clobber_return_register (void)
4551 diddle_return_value (do_clobber_return_reg, NULL);
4553 /* In case we do use pseudo to return value, clobber it too. */
4554 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4556 tree decl_result = DECL_RESULT (current_function_decl);
4557 rtx decl_rtl = DECL_RTL (decl_result);
4558 if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4560 do_clobber_return_reg (decl_rtl, NULL);
4565 static void
4566 do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4568 emit_use (reg);
4571 static void
4572 use_return_register (void)
4574 diddle_return_value (do_use_return_reg, NULL);
4577 /* Possibly warn about unused parameters. */
4578 void
4579 do_warn_unused_parameter (tree fn)
4581 tree decl;
4583 for (decl = DECL_ARGUMENTS (fn);
4584 decl; decl = TREE_CHAIN (decl))
4585 if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4586 && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4587 && !TREE_NO_WARNING (decl))
4588 warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4591 static GTY(()) rtx initial_trampoline;
4593 /* Generate RTL for the end of the current function. */
4595 void
4596 expand_function_end (void)
4598 rtx clobber_after;
4600 /* If arg_pointer_save_area was referenced only from a nested
4601 function, we will not have initialized it yet. Do that now. */
4602 if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4603 get_arg_pointer_save_area ();
4605 /* If we are doing generic stack checking and this function makes calls,
4606 do a stack probe at the start of the function to ensure we have enough
4607 space for another stack frame. */
4608 if (flag_stack_check == GENERIC_STACK_CHECK)
4610 rtx insn, seq;
4612 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4613 if (CALL_P (insn))
4615 start_sequence ();
4616 probe_stack_range (STACK_OLD_CHECK_PROTECT,
4617 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE));
4618 seq = get_insns ();
4619 end_sequence ();
4620 emit_insn_before (seq, stack_check_probe_note);
4621 break;
4625 /* End any sequences that failed to be closed due to syntax errors. */
4626 while (in_sequence_p ())
4627 end_sequence ();
4629 clear_pending_stack_adjust ();
4630 do_pending_stack_adjust ();
4632 /* Output a linenumber for the end of the function.
4633 SDB depends on this. */
4634 force_next_line_note ();
4635 set_curr_insn_source_location (input_location);
4637 /* Before the return label (if any), clobber the return
4638 registers so that they are not propagated live to the rest of
4639 the function. This can only happen with functions that drop
4640 through; if there had been a return statement, there would
4641 have either been a return rtx, or a jump to the return label.
4643 We delay actual code generation after the current_function_value_rtx
4644 is computed. */
4645 clobber_after = get_last_insn ();
4647 /* Output the label for the actual return from the function. */
4648 emit_label (return_label);
4650 if (USING_SJLJ_EXCEPTIONS)
4652 /* Let except.c know where it should emit the call to unregister
4653 the function context for sjlj exceptions. */
4654 if (flag_exceptions)
4655 sjlj_emit_function_exit_after (get_last_insn ());
4657 else
4659 /* We want to ensure that instructions that may trap are not
4660 moved into the epilogue by scheduling, because we don't
4661 always emit unwind information for the epilogue. */
4662 if (flag_non_call_exceptions)
4663 emit_insn (gen_blockage ());
4666 /* If this is an implementation of throw, do what's necessary to
4667 communicate between __builtin_eh_return and the epilogue. */
4668 expand_eh_return ();
4670 /* If scalar return value was computed in a pseudo-reg, or was a named
4671 return value that got dumped to the stack, copy that to the hard
4672 return register. */
4673 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4675 tree decl_result = DECL_RESULT (current_function_decl);
4676 rtx decl_rtl = DECL_RTL (decl_result);
4678 if (REG_P (decl_rtl)
4679 ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4680 : DECL_REGISTER (decl_result))
4682 rtx real_decl_rtl = crtl->return_rtx;
4684 /* This should be set in assign_parms. */
4685 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4687 /* If this is a BLKmode structure being returned in registers,
4688 then use the mode computed in expand_return. Note that if
4689 decl_rtl is memory, then its mode may have been changed,
4690 but that crtl->return_rtx has not. */
4691 if (GET_MODE (real_decl_rtl) == BLKmode)
4692 PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4694 /* If a non-BLKmode return value should be padded at the least
4695 significant end of the register, shift it left by the appropriate
4696 amount. BLKmode results are handled using the group load/store
4697 machinery. */
4698 if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4699 && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4701 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4702 REGNO (real_decl_rtl)),
4703 decl_rtl);
4704 shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4706 /* If a named return value dumped decl_return to memory, then
4707 we may need to re-do the PROMOTE_MODE signed/unsigned
4708 extension. */
4709 else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4711 int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4713 if (targetm.calls.promote_function_return (TREE_TYPE (current_function_decl)))
4714 promote_mode (TREE_TYPE (decl_result), GET_MODE (decl_rtl),
4715 &unsignedp, 1);
4717 convert_move (real_decl_rtl, decl_rtl, unsignedp);
4719 else if (GET_CODE (real_decl_rtl) == PARALLEL)
4721 /* If expand_function_start has created a PARALLEL for decl_rtl,
4722 move the result to the real return registers. Otherwise, do
4723 a group load from decl_rtl for a named return. */
4724 if (GET_CODE (decl_rtl) == PARALLEL)
4725 emit_group_move (real_decl_rtl, decl_rtl);
4726 else
4727 emit_group_load (real_decl_rtl, decl_rtl,
4728 TREE_TYPE (decl_result),
4729 int_size_in_bytes (TREE_TYPE (decl_result)));
4731 /* In the case of complex integer modes smaller than a word, we'll
4732 need to generate some non-trivial bitfield insertions. Do that
4733 on a pseudo and not the hard register. */
4734 else if (GET_CODE (decl_rtl) == CONCAT
4735 && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4736 && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4738 int old_generating_concat_p;
4739 rtx tmp;
4741 old_generating_concat_p = generating_concat_p;
4742 generating_concat_p = 0;
4743 tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4744 generating_concat_p = old_generating_concat_p;
4746 emit_move_insn (tmp, decl_rtl);
4747 emit_move_insn (real_decl_rtl, tmp);
4749 else
4750 emit_move_insn (real_decl_rtl, decl_rtl);
4754 /* If returning a structure, arrange to return the address of the value
4755 in a place where debuggers expect to find it.
4757 If returning a structure PCC style,
4758 the caller also depends on this value.
4759 And cfun->returns_pcc_struct is not necessarily set. */
4760 if (cfun->returns_struct
4761 || cfun->returns_pcc_struct)
4763 rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4764 tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4765 rtx outgoing;
4767 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4768 type = TREE_TYPE (type);
4769 else
4770 value_address = XEXP (value_address, 0);
4772 outgoing = targetm.calls.function_value (build_pointer_type (type),
4773 current_function_decl, true);
4775 /* Mark this as a function return value so integrate will delete the
4776 assignment and USE below when inlining this function. */
4777 REG_FUNCTION_VALUE_P (outgoing) = 1;
4779 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4780 value_address = convert_memory_address (GET_MODE (outgoing),
4781 value_address);
4783 emit_move_insn (outgoing, value_address);
4785 /* Show return register used to hold result (in this case the address
4786 of the result. */
4787 crtl->return_rtx = outgoing;
4790 /* Emit the actual code to clobber return register. */
4792 rtx seq;
4794 start_sequence ();
4795 clobber_return_register ();
4796 seq = get_insns ();
4797 end_sequence ();
4799 emit_insn_after (seq, clobber_after);
4802 /* Output the label for the naked return from the function. */
4803 if (naked_return_label)
4804 emit_label (naked_return_label);
4806 /* @@@ This is a kludge. We want to ensure that instructions that
4807 may trap are not moved into the epilogue by scheduling, because
4808 we don't always emit unwind information for the epilogue. */
4809 if (! USING_SJLJ_EXCEPTIONS && flag_non_call_exceptions)
4810 emit_insn (gen_blockage ());
4812 /* If stack protection is enabled for this function, check the guard. */
4813 if (crtl->stack_protect_guard)
4814 stack_protect_epilogue ();
4816 /* If we had calls to alloca, and this machine needs
4817 an accurate stack pointer to exit the function,
4818 insert some code to save and restore the stack pointer. */
4819 if (! EXIT_IGNORE_STACK
4820 && cfun->calls_alloca)
4822 rtx tem = 0;
4824 emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4825 emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4828 /* ??? This should no longer be necessary since stupid is no longer with
4829 us, but there are some parts of the compiler (eg reload_combine, and
4830 sh mach_dep_reorg) that still try and compute their own lifetime info
4831 instead of using the general framework. */
4832 use_return_register ();
4836 get_arg_pointer_save_area (void)
4838 rtx ret = arg_pointer_save_area;
4840 if (! ret)
4842 ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4843 arg_pointer_save_area = ret;
4846 if (! crtl->arg_pointer_save_area_init)
4848 rtx seq;
4850 /* Save the arg pointer at the beginning of the function. The
4851 generated stack slot may not be a valid memory address, so we
4852 have to check it and fix it if necessary. */
4853 start_sequence ();
4854 emit_move_insn (validize_mem (ret),
4855 crtl->args.internal_arg_pointer);
4856 seq = get_insns ();
4857 end_sequence ();
4859 push_topmost_sequence ();
4860 emit_insn_after (seq, entry_of_function ());
4861 pop_topmost_sequence ();
4864 return ret;
4867 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4868 for the first time. */
4870 static void
4871 record_insns (rtx insns, rtx end, htab_t *hashp)
4873 rtx tmp;
4874 htab_t hash = *hashp;
4876 if (hash == NULL)
4877 *hashp = hash
4878 = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
4880 for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
4882 void **slot = htab_find_slot (hash, tmp, INSERT);
4883 gcc_assert (*slot == NULL);
4884 *slot = tmp;
4888 /* INSN has been duplicated as COPY, as part of duping a basic block.
4889 If INSN is an epilogue insn, then record COPY as epilogue as well. */
4891 void
4892 maybe_copy_epilogue_insn (rtx insn, rtx copy)
4894 void **slot;
4896 if (epilogue_insn_hash == NULL
4897 || htab_find (epilogue_insn_hash, insn) == NULL)
4898 return;
4900 slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
4901 gcc_assert (*slot == NULL);
4902 *slot = copy;
4905 /* Set the locator of the insn chain starting at INSN to LOC. */
4906 static void
4907 set_insn_locators (rtx insn, int loc)
4909 while (insn != NULL_RTX)
4911 if (INSN_P (insn))
4912 INSN_LOCATOR (insn) = loc;
4913 insn = NEXT_INSN (insn);
4917 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
4918 we can be running after reorg, SEQUENCE rtl is possible. */
4920 static bool
4921 contains (const_rtx insn, htab_t hash)
4923 if (hash == NULL)
4924 return false;
4926 if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
4928 int i;
4929 for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4930 if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
4931 return true;
4932 return false;
4935 return htab_find (hash, insn) != NULL;
4939 prologue_epilogue_contains (const_rtx insn)
4941 if (contains (insn, prologue_insn_hash))
4942 return 1;
4943 if (contains (insn, epilogue_insn_hash))
4944 return 1;
4945 return 0;
4948 #ifdef HAVE_return
4949 /* Insert gen_return at the end of block BB. This also means updating
4950 block_for_insn appropriately. */
4952 static void
4953 emit_return_into_block (basic_block bb)
4955 emit_jump_insn_after (gen_return (), BB_END (bb));
4957 #endif /* HAVE_return */
4959 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4960 this into place with notes indicating where the prologue ends and where
4961 the epilogue begins. Update the basic block information when possible. */
4963 static void
4964 thread_prologue_and_epilogue_insns (void)
4966 int inserted = 0;
4967 edge e;
4968 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4969 rtx seq;
4970 #endif
4971 #if defined (HAVE_epilogue) || defined(HAVE_return)
4972 rtx epilogue_end = NULL_RTX;
4973 #endif
4974 edge_iterator ei;
4976 rtl_profile_for_bb (ENTRY_BLOCK_PTR);
4977 #ifdef HAVE_prologue
4978 if (HAVE_prologue)
4980 start_sequence ();
4981 seq = gen_prologue ();
4982 emit_insn (seq);
4984 /* Insert an explicit USE for the frame pointer
4985 if the profiling is on and the frame pointer is required. */
4986 if (crtl->profile && frame_pointer_needed)
4987 emit_use (hard_frame_pointer_rtx);
4989 /* Retain a map of the prologue insns. */
4990 record_insns (seq, NULL, &prologue_insn_hash);
4991 emit_note (NOTE_INSN_PROLOGUE_END);
4993 #ifndef PROFILE_BEFORE_PROLOGUE
4994 /* Ensure that instructions are not moved into the prologue when
4995 profiling is on. The call to the profiling routine can be
4996 emitted within the live range of a call-clobbered register. */
4997 if (crtl->profile)
4998 emit_insn (gen_blockage ());
4999 #endif
5001 seq = get_insns ();
5002 end_sequence ();
5003 set_insn_locators (seq, prologue_locator);
5005 /* Can't deal with multiple successors of the entry block
5006 at the moment. Function should always have at least one
5007 entry point. */
5008 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5010 insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5011 inserted = 1;
5013 #endif
5015 /* If the exit block has no non-fake predecessors, we don't need
5016 an epilogue. */
5017 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5018 if ((e->flags & EDGE_FAKE) == 0)
5019 break;
5020 if (e == NULL)
5021 goto epilogue_done;
5023 rtl_profile_for_bb (EXIT_BLOCK_PTR);
5024 #ifdef HAVE_return
5025 if (optimize && HAVE_return)
5027 /* If we're allowed to generate a simple return instruction,
5028 then by definition we don't need a full epilogue. Examine
5029 the block that falls through to EXIT. If it does not
5030 contain any code, examine its predecessors and try to
5031 emit (conditional) return instructions. */
5033 basic_block last;
5034 rtx label;
5036 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5037 if (e->flags & EDGE_FALLTHRU)
5038 break;
5039 if (e == NULL)
5040 goto epilogue_done;
5041 last = e->src;
5043 /* Verify that there are no active instructions in the last block. */
5044 label = BB_END (last);
5045 while (label && !LABEL_P (label))
5047 if (active_insn_p (label))
5048 break;
5049 label = PREV_INSN (label);
5052 if (BB_HEAD (last) == label && LABEL_P (label))
5054 edge_iterator ei2;
5056 for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5058 basic_block bb = e->src;
5059 rtx jump;
5061 if (bb == ENTRY_BLOCK_PTR)
5063 ei_next (&ei2);
5064 continue;
5067 jump = BB_END (bb);
5068 if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5070 ei_next (&ei2);
5071 continue;
5074 /* If we have an unconditional jump, we can replace that
5075 with a simple return instruction. */
5076 if (simplejump_p (jump))
5078 emit_return_into_block (bb);
5079 delete_insn (jump);
5082 /* If we have a conditional jump, we can try to replace
5083 that with a conditional return instruction. */
5084 else if (condjump_p (jump))
5086 if (! redirect_jump (jump, 0, 0))
5088 ei_next (&ei2);
5089 continue;
5092 /* If this block has only one successor, it both jumps
5093 and falls through to the fallthru block, so we can't
5094 delete the edge. */
5095 if (single_succ_p (bb))
5097 ei_next (&ei2);
5098 continue;
5101 else
5103 ei_next (&ei2);
5104 continue;
5107 /* Fix up the CFG for the successful change we just made. */
5108 redirect_edge_succ (e, EXIT_BLOCK_PTR);
5111 /* Emit a return insn for the exit fallthru block. Whether
5112 this is still reachable will be determined later. */
5114 emit_barrier_after (BB_END (last));
5115 emit_return_into_block (last);
5116 epilogue_end = BB_END (last);
5117 single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5118 goto epilogue_done;
5121 #endif
5123 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5124 this marker for the splits of EH_RETURN patterns, and nothing else
5125 uses the flag in the meantime. */
5126 epilogue_completed = 1;
5128 #ifdef HAVE_eh_return
5129 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5130 some targets, these get split to a special version of the epilogue
5131 code. In order to be able to properly annotate these with unwind
5132 info, try to split them now. If we get a valid split, drop an
5133 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5134 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5136 rtx prev, last, trial;
5138 if (e->flags & EDGE_FALLTHRU)
5139 continue;
5140 last = BB_END (e->src);
5141 if (!eh_returnjump_p (last))
5142 continue;
5144 prev = PREV_INSN (last);
5145 trial = try_split (PATTERN (last), last, 1);
5146 if (trial == last)
5147 continue;
5149 record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5150 emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5152 #endif
5154 /* Find the edge that falls through to EXIT. Other edges may exist
5155 due to RETURN instructions, but those don't need epilogues.
5156 There really shouldn't be a mixture -- either all should have
5157 been converted or none, however... */
5159 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5160 if (e->flags & EDGE_FALLTHRU)
5161 break;
5162 if (e == NULL)
5163 goto epilogue_done;
5165 #ifdef HAVE_epilogue
5166 if (HAVE_epilogue)
5168 start_sequence ();
5169 epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5170 seq = gen_epilogue ();
5171 emit_jump_insn (seq);
5173 /* Retain a map of the epilogue insns. */
5174 record_insns (seq, NULL, &epilogue_insn_hash);
5175 set_insn_locators (seq, epilogue_locator);
5177 seq = get_insns ();
5178 end_sequence ();
5180 insert_insn_on_edge (seq, e);
5181 inserted = 1;
5183 else
5184 #endif
5186 basic_block cur_bb;
5188 if (! next_active_insn (BB_END (e->src)))
5189 goto epilogue_done;
5190 /* We have a fall-through edge to the exit block, the source is not
5191 at the end of the function, and there will be an assembler epilogue
5192 at the end of the function.
5193 We can't use force_nonfallthru here, because that would try to
5194 use return. Inserting a jump 'by hand' is extremely messy, so
5195 we take advantage of cfg_layout_finalize using
5196 fixup_fallthru_exit_predecessor. */
5197 cfg_layout_initialize (0);
5198 FOR_EACH_BB (cur_bb)
5199 if (cur_bb->index >= NUM_FIXED_BLOCKS
5200 && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5201 cur_bb->aux = cur_bb->next_bb;
5202 cfg_layout_finalize ();
5204 epilogue_done:
5205 default_rtl_profile ();
5207 if (inserted)
5209 commit_edge_insertions ();
5211 /* The epilogue insns we inserted may cause the exit edge to no longer
5212 be fallthru. */
5213 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5215 if (((e->flags & EDGE_FALLTHRU) != 0)
5216 && returnjump_p (BB_END (e->src)))
5217 e->flags &= ~EDGE_FALLTHRU;
5221 #ifdef HAVE_sibcall_epilogue
5222 /* Emit sibling epilogues before any sibling call sites. */
5223 for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5225 basic_block bb = e->src;
5226 rtx insn = BB_END (bb);
5228 if (!CALL_P (insn)
5229 || ! SIBLING_CALL_P (insn))
5231 ei_next (&ei);
5232 continue;
5235 start_sequence ();
5236 emit_note (NOTE_INSN_EPILOGUE_BEG);
5237 emit_insn (gen_sibcall_epilogue ());
5238 seq = get_insns ();
5239 end_sequence ();
5241 /* Retain a map of the epilogue insns. Used in life analysis to
5242 avoid getting rid of sibcall epilogue insns. Do this before we
5243 actually emit the sequence. */
5244 record_insns (seq, NULL, &epilogue_insn_hash);
5245 set_insn_locators (seq, epilogue_locator);
5247 emit_insn_before (seq, insn);
5248 ei_next (&ei);
5250 #endif
5252 #ifdef HAVE_epilogue
5253 if (epilogue_end)
5255 rtx insn, next;
5257 /* Similarly, move any line notes that appear after the epilogue.
5258 There is no need, however, to be quite so anal about the existence
5259 of such a note. Also possibly move
5260 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5261 info generation. */
5262 for (insn = epilogue_end; insn; insn = next)
5264 next = NEXT_INSN (insn);
5265 if (NOTE_P (insn)
5266 && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5267 reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5270 #endif
5272 /* Threading the prologue and epilogue changes the artificial refs
5273 in the entry and exit blocks. */
5274 epilogue_completed = 1;
5275 df_update_entry_exit_and_calls ();
5278 /* Reposition the prologue-end and epilogue-begin notes after
5279 instruction scheduling. */
5281 void
5282 reposition_prologue_and_epilogue_notes (void)
5284 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5285 || defined (HAVE_sibcall_epilogue)
5286 rtx insn, last, note;
5287 basic_block bb;
5289 /* Since the hash table is created on demand, the fact that it is
5290 non-null is a signal that it is non-empty. */
5291 if (prologue_insn_hash != NULL)
5293 size_t len = htab_elements (prologue_insn_hash);
5294 last = 0, note = 0;
5296 /* Scan from the beginning until we reach the last prologue insn. */
5297 /* ??? While we do have the CFG intact, there are two problems:
5298 (1) The prologue can contain loops (typically probing the stack),
5299 which means that the end of the prologue isn't in the first bb.
5300 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5301 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5303 if (NOTE_P (insn))
5305 if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5306 note = insn;
5308 else if (contains (insn, prologue_insn_hash))
5310 last = insn;
5311 if (--len == 0)
5312 break;
5316 if (last)
5318 if (note == NULL)
5320 /* Scan forward looking for the PROLOGUE_END note. It should
5321 be right at the beginning of the block, possibly with other
5322 insn notes that got moved there. */
5323 for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5325 if (NOTE_P (note)
5326 && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5327 break;
5331 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5332 if (LABEL_P (last))
5333 last = NEXT_INSN (last);
5334 reorder_insns (note, note, last);
5338 if (epilogue_insn_hash != NULL)
5340 edge_iterator ei;
5341 edge e;
5343 FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5345 last = 0, note = 0;
5346 bb = e->src;
5348 /* Scan from the beginning until we reach the first epilogue insn.
5349 Take the cue for whether this is a plain or sibcall epilogue
5350 from the kind of note we find first. */
5351 FOR_BB_INSNS (bb, insn)
5353 if (NOTE_P (insn))
5355 if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5357 note = insn;
5358 if (last)
5359 break;
5362 else if (contains (insn, epilogue_insn_hash))
5364 last = insn;
5365 if (note != NULL)
5366 break;
5370 if (last && note && PREV_INSN (last) != note)
5371 reorder_insns (note, note, PREV_INSN (last));
5374 #endif /* HAVE_prologue or HAVE_epilogue */
5377 /* Returns the name of the current function. */
5378 const char *
5379 current_function_name (void)
5381 return lang_hooks.decl_printable_name (cfun->decl, 2);
5385 static unsigned int
5386 rest_of_handle_check_leaf_regs (void)
5388 #ifdef LEAF_REGISTERS
5389 current_function_uses_only_leaf_regs
5390 = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5391 #endif
5392 return 0;
5395 /* Insert a TYPE into the used types hash table of CFUN. */
5396 static void
5397 used_types_insert_helper (tree type, struct function *func)
5399 if (type != NULL && func != NULL)
5401 void **slot;
5403 if (func->used_types_hash == NULL)
5404 func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5405 htab_eq_pointer, NULL);
5406 slot = htab_find_slot (func->used_types_hash, type, INSERT);
5407 if (*slot == NULL)
5408 *slot = type;
5412 /* Given a type, insert it into the used hash table in cfun. */
5413 void
5414 used_types_insert (tree t)
5416 while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5417 t = TREE_TYPE (t);
5418 t = TYPE_MAIN_VARIANT (t);
5419 if (debug_info_level > DINFO_LEVEL_NONE)
5420 used_types_insert_helper (t, cfun);
5423 struct rtl_opt_pass pass_leaf_regs =
5426 RTL_PASS,
5427 NULL, /* name */
5428 NULL, /* gate */
5429 rest_of_handle_check_leaf_regs, /* execute */
5430 NULL, /* sub */
5431 NULL, /* next */
5432 0, /* static_pass_number */
5433 TV_NONE, /* tv_id */
5434 0, /* properties_required */
5435 0, /* properties_provided */
5436 0, /* properties_destroyed */
5437 0, /* todo_flags_start */
5438 0 /* todo_flags_finish */
5442 static unsigned int
5443 rest_of_handle_thread_prologue_and_epilogue (void)
5445 if (optimize)
5446 cleanup_cfg (CLEANUP_EXPENSIVE);
5447 /* On some machines, the prologue and epilogue code, or parts thereof,
5448 can be represented as RTL. Doing so lets us schedule insns between
5449 it and the rest of the code and also allows delayed branch
5450 scheduling to operate in the epilogue. */
5452 thread_prologue_and_epilogue_insns ();
5453 return 0;
5456 struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5459 RTL_PASS,
5460 "pro_and_epilogue", /* name */
5461 NULL, /* gate */
5462 rest_of_handle_thread_prologue_and_epilogue, /* execute */
5463 NULL, /* sub */
5464 NULL, /* next */
5465 0, /* static_pass_number */
5466 TV_THREAD_PROLOGUE_AND_EPILOGUE, /* tv_id */
5467 0, /* properties_required */
5468 0, /* properties_provided */
5469 0, /* properties_destroyed */
5470 TODO_verify_flow, /* todo_flags_start */
5471 TODO_dump_func |
5472 TODO_df_verify |
5473 TODO_df_finish | TODO_verify_rtl_sharing |
5474 TODO_ggc_collect /* todo_flags_finish */
5479 /* This mini-pass fixes fall-out from SSA in asm statements that have
5480 in-out constraints. Say you start with
5482 orig = inout;
5483 asm ("": "+mr" (inout));
5484 use (orig);
5486 which is transformed very early to use explicit output and match operands:
5488 orig = inout;
5489 asm ("": "=mr" (inout) : "0" (inout));
5490 use (orig);
5492 Or, after SSA and copyprop,
5494 asm ("": "=mr" (inout_2) : "0" (inout_1));
5495 use (inout_1);
5497 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5498 they represent two separate values, so they will get different pseudo
5499 registers during expansion. Then, since the two operands need to match
5500 per the constraints, but use different pseudo registers, reload can
5501 only register a reload for these operands. But reloads can only be
5502 satisfied by hardregs, not by memory, so we need a register for this
5503 reload, just because we are presented with non-matching operands.
5504 So, even though we allow memory for this operand, no memory can be
5505 used for it, just because the two operands don't match. This can
5506 cause reload failures on register-starved targets.
5508 So it's a symptom of reload not being able to use memory for reloads
5509 or, alternatively it's also a symptom of both operands not coming into
5510 reload as matching (in which case the pseudo could go to memory just
5511 fine, as the alternative allows it, and no reload would be necessary).
5512 We fix the latter problem here, by transforming
5514 asm ("": "=mr" (inout_2) : "0" (inout_1));
5516 back to
5518 inout_2 = inout_1;
5519 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5521 static void
5522 match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5524 int i;
5525 bool changed = false;
5526 rtx op = SET_SRC (p_sets[0]);
5527 int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5528 rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5529 bool *output_matched = XALLOCAVEC (bool, noutputs);
5531 memset (output_matched, 0, noutputs * sizeof (bool));
5532 for (i = 0; i < ninputs; i++)
5534 rtx input, output, insns;
5535 const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5536 char *end;
5537 int match, j;
5539 if (*constraint == '%')
5540 constraint++;
5542 match = strtoul (constraint, &end, 10);
5543 if (end == constraint)
5544 continue;
5546 gcc_assert (match < noutputs);
5547 output = SET_DEST (p_sets[match]);
5548 input = RTVEC_ELT (inputs, i);
5549 /* Only do the transformation for pseudos. */
5550 if (! REG_P (output)
5551 || rtx_equal_p (output, input)
5552 || (GET_MODE (input) != VOIDmode
5553 && GET_MODE (input) != GET_MODE (output)))
5554 continue;
5556 /* We can't do anything if the output is also used as input,
5557 as we're going to overwrite it. */
5558 for (j = 0; j < ninputs; j++)
5559 if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5560 break;
5561 if (j != ninputs)
5562 continue;
5564 /* Avoid changing the same input several times. For
5565 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5566 only change in once (to out1), rather than changing it
5567 first to out1 and afterwards to out2. */
5568 if (i > 0)
5570 for (j = 0; j < noutputs; j++)
5571 if (output_matched[j] && input == SET_DEST (p_sets[j]))
5572 break;
5573 if (j != noutputs)
5574 continue;
5576 output_matched[match] = true;
5578 start_sequence ();
5579 emit_move_insn (output, input);
5580 insns = get_insns ();
5581 end_sequence ();
5582 emit_insn_before (insns, insn);
5584 /* Now replace all mentions of the input with output. We can't
5585 just replace the occurrence in inputs[i], as the register might
5586 also be used in some other input (or even in an address of an
5587 output), which would mean possibly increasing the number of
5588 inputs by one (namely 'output' in addition), which might pose
5589 a too complicated problem for reload to solve. E.g. this situation:
5591 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5593 Here 'input' is used in two occurrences as input (once for the
5594 input operand, once for the address in the second output operand).
5595 If we would replace only the occurrence of the input operand (to
5596 make the matching) we would be left with this:
5598 output = input
5599 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5601 Now we suddenly have two different input values (containing the same
5602 value, but different pseudos) where we formerly had only one.
5603 With more complicated asms this might lead to reload failures
5604 which wouldn't have happen without this pass. So, iterate over
5605 all operands and replace all occurrences of the register used. */
5606 for (j = 0; j < noutputs; j++)
5607 if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5608 && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5609 SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5610 input, output);
5611 for (j = 0; j < ninputs; j++)
5612 if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5613 RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5614 input, output);
5616 changed = true;
5619 if (changed)
5620 df_insn_rescan (insn);
5623 static unsigned
5624 rest_of_match_asm_constraints (void)
5626 basic_block bb;
5627 rtx insn, pat, *p_sets;
5628 int noutputs;
5630 if (!crtl->has_asm_statement)
5631 return 0;
5633 df_set_flags (DF_DEFER_INSN_RESCAN);
5634 FOR_EACH_BB (bb)
5636 FOR_BB_INSNS (bb, insn)
5638 if (!INSN_P (insn))
5639 continue;
5641 pat = PATTERN (insn);
5642 if (GET_CODE (pat) == PARALLEL)
5643 p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5644 else if (GET_CODE (pat) == SET)
5645 p_sets = &PATTERN (insn), noutputs = 1;
5646 else
5647 continue;
5649 if (GET_CODE (*p_sets) == SET
5650 && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5651 match_asm_constraints_1 (insn, p_sets, noutputs);
5655 return TODO_df_finish;
5658 struct rtl_opt_pass pass_match_asm_constraints =
5661 RTL_PASS,
5662 "asmcons", /* name */
5663 NULL, /* gate */
5664 rest_of_match_asm_constraints, /* execute */
5665 NULL, /* sub */
5666 NULL, /* next */
5667 0, /* static_pass_number */
5668 TV_NONE, /* tv_id */
5669 0, /* properties_required */
5670 0, /* properties_provided */
5671 0, /* properties_destroyed */
5672 0, /* todo_flags_start */
5673 TODO_dump_func /* todo_flags_finish */
5678 #include "gt-function.h"