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[/] [openrisc/] [trunk/] [gnu-src/] [gcc-4.5.1/] [gcc/] [function.c] - Blame information for rev 378

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1 280 jeremybenn
/* 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
   2010  Free Software Foundation, Inc.
5
 
6
This file is part of GCC.
7
 
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.
12
 
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.
17
 
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/>.  */
21
 
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.
26
 
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.
30
 
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.  */
35
 
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"
68
 
69
/* So we can assign to cfun in this file.  */
70
#undef cfun
71
 
72
#ifndef STACK_ALIGNMENT_NEEDED
73
#define STACK_ALIGNMENT_NEEDED 1
74
#endif
75
 
76
#define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
77
 
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
85
 
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))
90
 
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))
94
 
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;
100
 
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;
105
 
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;
110
 
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;
116
 
117
/* Assign unique numbers to labels generated for profiling, debugging, etc.  */
118
static GTY(()) int funcdef_no;
119
 
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);
123
 
124
/* The currently compiled function.  */
125
struct function *cfun = 0;
126
 
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;
132
 
133
 
134
htab_t types_used_by_vars_hash = NULL;
135
tree types_used_by_cur_var_decl = NULL;
136
 
137
/* Forward declarations.  */
138
 
139
static struct temp_slot *find_temp_slot_from_address (rtx);
140
static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
141
static void pad_below (struct args_size *, enum machine_mode, tree);
142
static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
143
static int all_blocks (tree, tree *);
144
static tree *get_block_vector (tree, int *);
145
extern tree debug_find_var_in_block_tree (tree, tree);
146
/* We always define `record_insns' even if it's not used so that we
147
   can always export `prologue_epilogue_contains'.  */
148
static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
149
static bool contains (const_rtx, htab_t);
150
#ifdef HAVE_return
151
static void emit_return_into_block (basic_block);
152
#endif
153
static void prepare_function_start (void);
154
static void do_clobber_return_reg (rtx, void *);
155
static void do_use_return_reg (rtx, void *);
156
static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
157
 
158
/* Stack of nested functions.  */
159
/* Keep track of the cfun stack.  */
160
 
161
typedef struct function *function_p;
162
 
163
DEF_VEC_P(function_p);
164
DEF_VEC_ALLOC_P(function_p,heap);
165
static VEC(function_p,heap) *function_context_stack;
166
 
167
/* Save the current context for compilation of a nested function.
168
   This is called from language-specific code.  */
169
 
170
void
171
push_function_context (void)
172
{
173
  if (cfun == 0)
174
    allocate_struct_function (NULL, false);
175
 
176
  VEC_safe_push (function_p, heap, function_context_stack, cfun);
177
  set_cfun (NULL);
178
}
179
 
180
/* Restore the last saved context, at the end of a nested function.
181
   This function is called from language-specific code.  */
182
 
183
void
184
pop_function_context (void)
185
{
186
  struct function *p = VEC_pop (function_p, function_context_stack);
187
  set_cfun (p);
188
  current_function_decl = p->decl;
189
 
190
  /* Reset variables that have known state during rtx generation.  */
191
  virtuals_instantiated = 0;
192
  generating_concat_p = 1;
193
}
194
 
195
/* Clear out all parts of the state in F that can safely be discarded
196
   after the function has been parsed, but not compiled, to let
197
   garbage collection reclaim the memory.  */
198
 
199
void
200
free_after_parsing (struct function *f)
201
{
202
  f->language = 0;
203
}
204
 
205
/* Clear out all parts of the state in F that can safely be discarded
206
   after the function has been compiled, to let garbage collection
207
   reclaim the memory.  */
208
 
209
void
210
free_after_compilation (struct function *f)
211
{
212
  prologue_insn_hash = NULL;
213
  epilogue_insn_hash = NULL;
214
 
215
  if (crtl->emit.regno_pointer_align)
216
    free (crtl->emit.regno_pointer_align);
217
 
218
  memset (crtl, 0, sizeof (struct rtl_data));
219
  f->eh = NULL;
220
  f->machine = NULL;
221
  f->cfg = NULL;
222
 
223
  regno_reg_rtx = NULL;
224
  insn_locators_free ();
225
}
226
 
227
/* Return size needed for stack frame based on slots so far allocated.
228
   This size counts from zero.  It is not rounded to PREFERRED_STACK_BOUNDARY;
229
   the caller may have to do that.  */
230
 
231
HOST_WIDE_INT
232
get_frame_size (void)
233
{
234
  if (FRAME_GROWS_DOWNWARD)
235
    return -frame_offset;
236
  else
237
    return frame_offset;
238
}
239
 
240
/* Issue an error message and return TRUE if frame OFFSET overflows in
241
   the signed target pointer arithmetics for function FUNC.  Otherwise
242
   return FALSE.  */
243
 
244
bool
245
frame_offset_overflow (HOST_WIDE_INT offset, tree func)
246
{
247
  unsigned HOST_WIDE_INT size = FRAME_GROWS_DOWNWARD ? -offset : offset;
248
 
249
  if (size > ((unsigned HOST_WIDE_INT) 1 << (GET_MODE_BITSIZE (Pmode) - 1))
250
               /* Leave room for the fixed part of the frame.  */
251
               - 64 * UNITS_PER_WORD)
252
    {
253
      error_at (DECL_SOURCE_LOCATION (func),
254
                "total size of local objects too large");
255
      return TRUE;
256
    }
257
 
258
  return FALSE;
259
}
260
 
261
/* Return stack slot alignment in bits for TYPE and MODE.  */
262
 
263
static unsigned int
264
get_stack_local_alignment (tree type, enum machine_mode mode)
265
{
266
  unsigned int alignment;
267
 
268
  if (mode == BLKmode)
269
    alignment = BIGGEST_ALIGNMENT;
270
  else
271
    alignment = GET_MODE_ALIGNMENT (mode);
272
 
273
  /* Allow the frond-end to (possibly) increase the alignment of this
274
     stack slot.  */
275
  if (! type)
276
    type = lang_hooks.types.type_for_mode (mode, 0);
277
 
278
  return STACK_SLOT_ALIGNMENT (type, mode, alignment);
279
}
280
 
281
/* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
282
   with machine mode MODE.
283
 
284
   ALIGN controls the amount of alignment for the address of the slot:
285
 
286
   -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
287
   -2 means use BITS_PER_UNIT,
288
   positive specifies alignment boundary in bits.
289
 
290
   If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
291
 
292
   We do not round to stack_boundary here.  */
293
 
294
rtx
295
assign_stack_local_1 (enum machine_mode mode, HOST_WIDE_INT size,
296
                      int align,
297
                      bool reduce_alignment_ok ATTRIBUTE_UNUSED)
298
{
299
  rtx x, addr;
300
  int bigend_correction = 0;
301
  unsigned int alignment, alignment_in_bits;
302
  int frame_off, frame_alignment, frame_phase;
303
 
304
  if (align == 0)
305
    {
306
      alignment = get_stack_local_alignment (NULL, mode);
307
      alignment /= BITS_PER_UNIT;
308
    }
309
  else if (align == -1)
310
    {
311
      alignment = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
312
      size = CEIL_ROUND (size, alignment);
313
    }
314
  else if (align == -2)
315
    alignment = 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
316
  else
317
    alignment = align / BITS_PER_UNIT;
318
 
319
  alignment_in_bits = alignment * BITS_PER_UNIT;
320
 
321
  if (FRAME_GROWS_DOWNWARD)
322
    frame_offset -= size;
323
 
324
  /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT.  */
325
  if (alignment_in_bits > MAX_SUPPORTED_STACK_ALIGNMENT)
326
    {
327
      alignment_in_bits = MAX_SUPPORTED_STACK_ALIGNMENT;
328
      alignment = alignment_in_bits / BITS_PER_UNIT;
329
    }
330
 
331
  if (SUPPORTS_STACK_ALIGNMENT)
332
    {
333
      if (crtl->stack_alignment_estimated < alignment_in_bits)
334
        {
335
          if (!crtl->stack_realign_processed)
336
            crtl->stack_alignment_estimated = alignment_in_bits;
337
          else
338
            {
339
              /* If stack is realigned and stack alignment value
340
                 hasn't been finalized, it is OK not to increase
341
                 stack_alignment_estimated.  The bigger alignment
342
                 requirement is recorded in stack_alignment_needed
343
                 below.  */
344
              gcc_assert (!crtl->stack_realign_finalized);
345
              if (!crtl->stack_realign_needed)
346
                {
347
                  /* It is OK to reduce the alignment as long as the
348
                     requested size is 0 or the estimated stack
349
                     alignment >= mode alignment.  */
350
                  gcc_assert (reduce_alignment_ok
351
                              || size == 0
352
                              || (crtl->stack_alignment_estimated
353
                                  >= GET_MODE_ALIGNMENT (mode)));
354
                  alignment_in_bits = crtl->stack_alignment_estimated;
355
                  alignment = alignment_in_bits / BITS_PER_UNIT;
356
                }
357
            }
358
        }
359
    }
360
 
361
  if (crtl->stack_alignment_needed < alignment_in_bits)
362
    crtl->stack_alignment_needed = alignment_in_bits;
363
  if (crtl->max_used_stack_slot_alignment < alignment_in_bits)
364
    crtl->max_used_stack_slot_alignment = alignment_in_bits;
365
 
366
  /* Calculate how many bytes the start of local variables is off from
367
     stack alignment.  */
368
  frame_alignment = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
369
  frame_off = STARTING_FRAME_OFFSET % frame_alignment;
370
  frame_phase = frame_off ? frame_alignment - frame_off : 0;
371
 
372
  /* Round the frame offset to the specified alignment.  The default is
373
     to always honor requests to align the stack but a port may choose to
374
     do its own stack alignment by defining STACK_ALIGNMENT_NEEDED.  */
375
  if (STACK_ALIGNMENT_NEEDED
376
      || mode != BLKmode
377
      || size != 0)
378
    {
379
      /*  We must be careful here, since FRAME_OFFSET might be negative and
380
          division with a negative dividend isn't as well defined as we might
381
          like.  So we instead assume that ALIGNMENT is a power of two and
382
          use logical operations which are unambiguous.  */
383
      if (FRAME_GROWS_DOWNWARD)
384
        frame_offset
385
          = (FLOOR_ROUND (frame_offset - frame_phase,
386
                          (unsigned HOST_WIDE_INT) alignment)
387
             + frame_phase);
388
      else
389
        frame_offset
390
          = (CEIL_ROUND (frame_offset - frame_phase,
391
                         (unsigned HOST_WIDE_INT) alignment)
392
             + frame_phase);
393
    }
394
 
395
  /* On a big-endian machine, if we are allocating more space than we will use,
396
     use the least significant bytes of those that are allocated.  */
397
  if (BYTES_BIG_ENDIAN && mode != BLKmode && GET_MODE_SIZE (mode) < size)
398
    bigend_correction = size - GET_MODE_SIZE (mode);
399
 
400
  /* If we have already instantiated virtual registers, return the actual
401
     address relative to the frame pointer.  */
402
  if (virtuals_instantiated)
403
    addr = plus_constant (frame_pointer_rtx,
404
                          trunc_int_for_mode
405
                          (frame_offset + bigend_correction
406
                           + STARTING_FRAME_OFFSET, Pmode));
407
  else
408
    addr = plus_constant (virtual_stack_vars_rtx,
409
                          trunc_int_for_mode
410
                          (frame_offset + bigend_correction,
411
                           Pmode));
412
 
413
  if (!FRAME_GROWS_DOWNWARD)
414
    frame_offset += size;
415
 
416
  x = gen_rtx_MEM (mode, addr);
417
  set_mem_align (x, alignment_in_bits);
418
  MEM_NOTRAP_P (x) = 1;
419
 
420
  stack_slot_list
421
    = gen_rtx_EXPR_LIST (VOIDmode, x, stack_slot_list);
422
 
423
  if (frame_offset_overflow (frame_offset, current_function_decl))
424
    frame_offset = 0;
425
 
426
  return x;
427
}
428
 
429
/* Wrap up assign_stack_local_1 with last parameter as false.  */
430
 
431
rtx
432
assign_stack_local (enum machine_mode mode, HOST_WIDE_INT size, int align)
433
{
434
  return assign_stack_local_1 (mode, size, align, false);
435
}
436
 
437
 
438
/* In order to evaluate some expressions, such as function calls returning
439
   structures in memory, we need to temporarily allocate stack locations.
440
   We record each allocated temporary in the following structure.
441
 
442
   Associated with each temporary slot is a nesting level.  When we pop up
443
   one level, all temporaries associated with the previous level are freed.
444
   Normally, all temporaries are freed after the execution of the statement
445
   in which they were created.  However, if we are inside a ({...}) grouping,
446
   the result may be in a temporary and hence must be preserved.  If the
447
   result could be in a temporary, we preserve it if we can determine which
448
   one it is in.  If we cannot determine which temporary may contain the
449
   result, all temporaries are preserved.  A temporary is preserved by
450
   pretending it was allocated at the previous nesting level.
451
 
452
   Automatic variables are also assigned temporary slots, at the nesting
453
   level where they are defined.  They are marked a "kept" so that
454
   free_temp_slots will not free them.  */
455
 
456
struct GTY(()) temp_slot {
457
  /* Points to next temporary slot.  */
458
  struct temp_slot *next;
459
  /* Points to previous temporary slot.  */
460
  struct temp_slot *prev;
461
  /* The rtx to used to reference the slot.  */
462
  rtx slot;
463
  /* The size, in units, of the slot.  */
464
  HOST_WIDE_INT size;
465
  /* The type of the object in the slot, or zero if it doesn't correspond
466
     to a type.  We use this to determine whether a slot can be reused.
467
     It can be reused if objects of the type of the new slot will always
468
     conflict with objects of the type of the old slot.  */
469
  tree type;
470
  /* The alignment (in bits) of the slot.  */
471
  unsigned int align;
472
  /* Nonzero if this temporary is currently in use.  */
473
  char in_use;
474
  /* Nonzero if this temporary has its address taken.  */
475
  char addr_taken;
476
  /* Nesting level at which this slot is being used.  */
477
  int level;
478
  /* Nonzero if this should survive a call to free_temp_slots.  */
479
  int keep;
480
  /* The offset of the slot from the frame_pointer, including extra space
481
     for alignment.  This info is for combine_temp_slots.  */
482
  HOST_WIDE_INT base_offset;
483
  /* The size of the slot, including extra space for alignment.  This
484
     info is for combine_temp_slots.  */
485
  HOST_WIDE_INT full_size;
486
};
487
 
488
/* A table of addresses that represent a stack slot.  The table is a mapping
489
   from address RTXen to a temp slot.  */
490
static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
491
 
492
/* Entry for the above hash table.  */
493
struct GTY(()) temp_slot_address_entry {
494
  hashval_t hash;
495
  rtx address;
496
  struct temp_slot *temp_slot;
497
};
498
 
499
/* Removes temporary slot TEMP from LIST.  */
500
 
501
static void
502
cut_slot_from_list (struct temp_slot *temp, struct temp_slot **list)
503
{
504
  if (temp->next)
505
    temp->next->prev = temp->prev;
506
  if (temp->prev)
507
    temp->prev->next = temp->next;
508
  else
509
    *list = temp->next;
510
 
511
  temp->prev = temp->next = NULL;
512
}
513
 
514
/* Inserts temporary slot TEMP to LIST.  */
515
 
516
static void
517
insert_slot_to_list (struct temp_slot *temp, struct temp_slot **list)
518
{
519
  temp->next = *list;
520
  if (*list)
521
    (*list)->prev = temp;
522
  temp->prev = NULL;
523
  *list = temp;
524
}
525
 
526
/* Returns the list of used temp slots at LEVEL.  */
527
 
528
static struct temp_slot **
529
temp_slots_at_level (int level)
530
{
531
  if (level >= (int) VEC_length (temp_slot_p, used_temp_slots))
532
    VEC_safe_grow_cleared (temp_slot_p, gc, used_temp_slots, level + 1);
533
 
534
  return &(VEC_address (temp_slot_p, used_temp_slots)[level]);
535
}
536
 
537
/* Returns the maximal temporary slot level.  */
538
 
539
static int
540
max_slot_level (void)
541
{
542
  if (!used_temp_slots)
543
    return -1;
544
 
545
  return VEC_length (temp_slot_p, used_temp_slots) - 1;
546
}
547
 
548
/* Moves temporary slot TEMP to LEVEL.  */
549
 
550
static void
551
move_slot_to_level (struct temp_slot *temp, int level)
552
{
553
  cut_slot_from_list (temp, temp_slots_at_level (temp->level));
554
  insert_slot_to_list (temp, temp_slots_at_level (level));
555
  temp->level = level;
556
}
557
 
558
/* Make temporary slot TEMP available.  */
559
 
560
static void
561
make_slot_available (struct temp_slot *temp)
562
{
563
  cut_slot_from_list (temp, temp_slots_at_level (temp->level));
564
  insert_slot_to_list (temp, &avail_temp_slots);
565
  temp->in_use = 0;
566
  temp->level = -1;
567
}
568
 
569
/* Compute the hash value for an address -> temp slot mapping.
570
   The value is cached on the mapping entry.  */
571
static hashval_t
572
temp_slot_address_compute_hash (struct temp_slot_address_entry *t)
573
{
574
  int do_not_record = 0;
575
  return hash_rtx (t->address, GET_MODE (t->address),
576
                   &do_not_record, NULL, false);
577
}
578
 
579
/* Return the hash value for an address -> temp slot mapping.  */
580
static hashval_t
581
temp_slot_address_hash (const void *p)
582
{
583
  const struct temp_slot_address_entry *t;
584
  t = (const struct temp_slot_address_entry *) p;
585
  return t->hash;
586
}
587
 
588
/* Compare two address -> temp slot mapping entries.  */
589
static int
590
temp_slot_address_eq (const void *p1, const void *p2)
591
{
592
  const struct temp_slot_address_entry *t1, *t2;
593
  t1 = (const struct temp_slot_address_entry *) p1;
594
  t2 = (const struct temp_slot_address_entry *) p2;
595
  return exp_equiv_p (t1->address, t2->address, 0, true);
596
}
597
 
598
/* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping.  */
599
static void
600
insert_temp_slot_address (rtx address, struct temp_slot *temp_slot)
601
{
602
  void **slot;
603
  struct temp_slot_address_entry *t = GGC_NEW (struct temp_slot_address_entry);
604
  t->address = address;
605
  t->temp_slot = temp_slot;
606
  t->hash = temp_slot_address_compute_hash (t);
607
  slot = htab_find_slot_with_hash (temp_slot_address_table, t, t->hash, INSERT);
608
  *slot = t;
609
}
610
 
611
/* Remove an address -> temp slot mapping entry if the temp slot is
612
   not in use anymore.  Callback for remove_unused_temp_slot_addresses.  */
613
static int
614
remove_unused_temp_slot_addresses_1 (void **slot, void *data ATTRIBUTE_UNUSED)
615
{
616
  const struct temp_slot_address_entry *t;
617
  t = (const struct temp_slot_address_entry *) *slot;
618
  if (! t->temp_slot->in_use)
619
    *slot = NULL;
620
  return 1;
621
}
622
 
623
/* Remove all mappings of addresses to unused temp slots.  */
624
static void
625
remove_unused_temp_slot_addresses (void)
626
{
627
  htab_traverse (temp_slot_address_table,
628
                 remove_unused_temp_slot_addresses_1,
629
                 NULL);
630
}
631
 
632
/* Find the temp slot corresponding to the object at address X.  */
633
 
634
static struct temp_slot *
635
find_temp_slot_from_address (rtx x)
636
{
637
  struct temp_slot *p;
638
  struct temp_slot_address_entry tmp, *t;
639
 
640
  /* First try the easy way:
641
     See if X exists in the address -> temp slot mapping.  */
642
  tmp.address = x;
643
  tmp.temp_slot = NULL;
644
  tmp.hash = temp_slot_address_compute_hash (&tmp);
645
  t = (struct temp_slot_address_entry *)
646
    htab_find_with_hash (temp_slot_address_table, &tmp, tmp.hash);
647
  if (t)
648
    return t->temp_slot;
649
 
650
  /* If we have a sum involving a register, see if it points to a temp
651
     slot.  */
652
  if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 0))
653
      && (p = find_temp_slot_from_address (XEXP (x, 0))) != 0)
654
    return p;
655
  else if (GET_CODE (x) == PLUS && REG_P (XEXP (x, 1))
656
           && (p = find_temp_slot_from_address (XEXP (x, 1))) != 0)
657
    return p;
658
 
659
  /* Last resort: Address is a virtual stack var address.  */
660
  if (GET_CODE (x) == PLUS
661
      && XEXP (x, 0) == virtual_stack_vars_rtx
662
      && CONST_INT_P (XEXP (x, 1)))
663
    {
664
      int i;
665
      for (i = max_slot_level (); i >= 0; i--)
666
        for (p = *temp_slots_at_level (i); p; p = p->next)
667
          {
668
            if (INTVAL (XEXP (x, 1)) >= p->base_offset
669
                && INTVAL (XEXP (x, 1)) < p->base_offset + p->full_size)
670
              return p;
671
          }
672
    }
673
 
674
  return NULL;
675
}
676
 
677
/* Allocate a temporary stack slot and record it for possible later
678
   reuse.
679
 
680
   MODE is the machine mode to be given to the returned rtx.
681
 
682
   SIZE is the size in units of the space required.  We do no rounding here
683
   since assign_stack_local will do any required rounding.
684
 
685
   KEEP is 1 if this slot is to be retained after a call to
686
   free_temp_slots.  Automatic variables for a block are allocated
687
   with this flag.  KEEP values of 2 or 3 were needed respectively
688
   for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
689
   or for SAVE_EXPRs, but they are now unused.
690
 
691
   TYPE is the type that will be used for the stack slot.  */
692
 
693
rtx
694
assign_stack_temp_for_type (enum machine_mode mode, HOST_WIDE_INT size,
695
                            int keep, tree type)
696
{
697
  unsigned int align;
698
  struct temp_slot *p, *best_p = 0, *selected = NULL, **pp;
699
  rtx slot;
700
 
701
  /* If SIZE is -1 it means that somebody tried to allocate a temporary
702
     of a variable size.  */
703
  gcc_assert (size != -1);
704
 
705
  /* These are now unused.  */
706
  gcc_assert (keep <= 1);
707
 
708
  align = get_stack_local_alignment (type, mode);
709
 
710
  /* Try to find an available, already-allocated temporary of the proper
711
     mode which meets the size and alignment requirements.  Choose the
712
     smallest one with the closest alignment.
713
 
714
     If assign_stack_temp is called outside of the tree->rtl expansion,
715
     we cannot reuse the stack slots (that may still refer to
716
     VIRTUAL_STACK_VARS_REGNUM).  */
717
  if (!virtuals_instantiated)
718
    {
719
      for (p = avail_temp_slots; p; p = p->next)
720
        {
721
          if (p->align >= align && p->size >= size
722
              && GET_MODE (p->slot) == mode
723
              && objects_must_conflict_p (p->type, type)
724
              && (best_p == 0 || best_p->size > p->size
725
                  || (best_p->size == p->size && best_p->align > p->align)))
726
            {
727
              if (p->align == align && p->size == size)
728
                {
729
                  selected = p;
730
                  cut_slot_from_list (selected, &avail_temp_slots);
731
                  best_p = 0;
732
                  break;
733
                }
734
              best_p = p;
735
            }
736
        }
737
    }
738
 
739
  /* Make our best, if any, the one to use.  */
740
  if (best_p)
741
    {
742
      selected = best_p;
743
      cut_slot_from_list (selected, &avail_temp_slots);
744
 
745
      /* If there are enough aligned bytes left over, make them into a new
746
         temp_slot so that the extra bytes don't get wasted.  Do this only
747
         for BLKmode slots, so that we can be sure of the alignment.  */
748
      if (GET_MODE (best_p->slot) == BLKmode)
749
        {
750
          int alignment = best_p->align / BITS_PER_UNIT;
751
          HOST_WIDE_INT rounded_size = CEIL_ROUND (size, alignment);
752
 
753
          if (best_p->size - rounded_size >= alignment)
754
            {
755
              p = GGC_NEW (struct temp_slot);
756
              p->in_use = p->addr_taken = 0;
757
              p->size = best_p->size - rounded_size;
758
              p->base_offset = best_p->base_offset + rounded_size;
759
              p->full_size = best_p->full_size - rounded_size;
760
              p->slot = adjust_address_nv (best_p->slot, BLKmode, rounded_size);
761
              p->align = best_p->align;
762
              p->type = best_p->type;
763
              insert_slot_to_list (p, &avail_temp_slots);
764
 
765
              stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, p->slot,
766
                                                   stack_slot_list);
767
 
768
              best_p->size = rounded_size;
769
              best_p->full_size = rounded_size;
770
            }
771
        }
772
    }
773
 
774
  /* If we still didn't find one, make a new temporary.  */
775
  if (selected == 0)
776
    {
777
      HOST_WIDE_INT frame_offset_old = frame_offset;
778
 
779
      p = GGC_NEW (struct temp_slot);
780
 
781
      /* We are passing an explicit alignment request to assign_stack_local.
782
         One side effect of that is assign_stack_local will not round SIZE
783
         to ensure the frame offset remains suitably aligned.
784
 
785
         So for requests which depended on the rounding of SIZE, we go ahead
786
         and round it now.  We also make sure ALIGNMENT is at least
787
         BIGGEST_ALIGNMENT.  */
788
      gcc_assert (mode != BLKmode || align == BIGGEST_ALIGNMENT);
789
      p->slot = assign_stack_local (mode,
790
                                    (mode == BLKmode
791
                                     ? CEIL_ROUND (size, (int) align / BITS_PER_UNIT)
792
                                     : size),
793
                                    align);
794
 
795
      p->align = align;
796
 
797
      /* The following slot size computation is necessary because we don't
798
         know the actual size of the temporary slot until assign_stack_local
799
         has performed all the frame alignment and size rounding for the
800
         requested temporary.  Note that extra space added for alignment
801
         can be either above or below this stack slot depending on which
802
         way the frame grows.  We include the extra space if and only if it
803
         is above this slot.  */
804
      if (FRAME_GROWS_DOWNWARD)
805
        p->size = frame_offset_old - frame_offset;
806
      else
807
        p->size = size;
808
 
809
      /* Now define the fields used by combine_temp_slots.  */
810
      if (FRAME_GROWS_DOWNWARD)
811
        {
812
          p->base_offset = frame_offset;
813
          p->full_size = frame_offset_old - frame_offset;
814
        }
815
      else
816
        {
817
          p->base_offset = frame_offset_old;
818
          p->full_size = frame_offset - frame_offset_old;
819
        }
820
 
821
      selected = p;
822
    }
823
 
824
  p = selected;
825
  p->in_use = 1;
826
  p->addr_taken = 0;
827
  p->type = type;
828
  p->level = temp_slot_level;
829
  p->keep = keep;
830
 
831
  pp = temp_slots_at_level (p->level);
832
  insert_slot_to_list (p, pp);
833
  insert_temp_slot_address (XEXP (p->slot, 0), p);
834
 
835
  /* Create a new MEM rtx to avoid clobbering MEM flags of old slots.  */
836
  slot = gen_rtx_MEM (mode, XEXP (p->slot, 0));
837
  stack_slot_list = gen_rtx_EXPR_LIST (VOIDmode, slot, stack_slot_list);
838
 
839
  /* If we know the alias set for the memory that will be used, use
840
     it.  If there's no TYPE, then we don't know anything about the
841
     alias set for the memory.  */
842
  set_mem_alias_set (slot, type ? get_alias_set (type) : 0);
843
  set_mem_align (slot, align);
844
 
845
  /* If a type is specified, set the relevant flags.  */
846
  if (type != 0)
847
    {
848
      MEM_VOLATILE_P (slot) = TYPE_VOLATILE (type);
849
      MEM_SET_IN_STRUCT_P (slot, (AGGREGATE_TYPE_P (type)
850
                                  || TREE_CODE (type) == COMPLEX_TYPE));
851
    }
852
  MEM_NOTRAP_P (slot) = 1;
853
 
854
  return slot;
855
}
856
 
857
/* Allocate a temporary stack slot and record it for possible later
858
   reuse.  First three arguments are same as in preceding function.  */
859
 
860
rtx
861
assign_stack_temp (enum machine_mode mode, HOST_WIDE_INT size, int keep)
862
{
863
  return assign_stack_temp_for_type (mode, size, keep, NULL_TREE);
864
}
865
 
866
/* Assign a temporary.
867
   If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
868
   and so that should be used in error messages.  In either case, we
869
   allocate of the given type.
870
   KEEP is as for assign_stack_temp.
871
   MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
872
   it is 0 if a register is OK.
873
   DONT_PROMOTE is 1 if we should not promote values in register
874
   to wider modes.  */
875
 
876
rtx
877
assign_temp (tree type_or_decl, int keep, int memory_required,
878
             int dont_promote ATTRIBUTE_UNUSED)
879
{
880
  tree type, decl;
881
  enum machine_mode mode;
882
#ifdef PROMOTE_MODE
883
  int unsignedp;
884
#endif
885
 
886
  if (DECL_P (type_or_decl))
887
    decl = type_or_decl, type = TREE_TYPE (decl);
888
  else
889
    decl = NULL, type = type_or_decl;
890
 
891
  mode = TYPE_MODE (type);
892
#ifdef PROMOTE_MODE
893
  unsignedp = TYPE_UNSIGNED (type);
894
#endif
895
 
896
  if (mode == BLKmode || memory_required)
897
    {
898
      HOST_WIDE_INT size = int_size_in_bytes (type);
899
      rtx tmp;
900
 
901
      /* Zero sized arrays are GNU C extension.  Set size to 1 to avoid
902
         problems with allocating the stack space.  */
903
      if (size == 0)
904
        size = 1;
905
 
906
      /* Unfortunately, we don't yet know how to allocate variable-sized
907
         temporaries.  However, sometimes we can find a fixed upper limit on
908
         the size, so try that instead.  */
909
      else if (size == -1)
910
        size = max_int_size_in_bytes (type);
911
 
912
      /* The size of the temporary may be too large to fit into an integer.  */
913
      /* ??? Not sure this should happen except for user silliness, so limit
914
         this to things that aren't compiler-generated temporaries.  The
915
         rest of the time we'll die in assign_stack_temp_for_type.  */
916
      if (decl && size == -1
917
          && TREE_CODE (TYPE_SIZE_UNIT (type)) == INTEGER_CST)
918
        {
919
          error ("size of variable %q+D is too large", decl);
920
          size = 1;
921
        }
922
 
923
      tmp = assign_stack_temp_for_type (mode, size, keep, type);
924
      return tmp;
925
    }
926
 
927
#ifdef PROMOTE_MODE
928
  if (! dont_promote)
929
    mode = promote_mode (type, mode, &unsignedp);
930
#endif
931
 
932
  return gen_reg_rtx (mode);
933
}
934
 
935
/* Combine temporary stack slots which are adjacent on the stack.
936
 
937
   This allows for better use of already allocated stack space.  This is only
938
   done for BLKmode slots because we can be sure that we won't have alignment
939
   problems in this case.  */
940
 
941
static void
942
combine_temp_slots (void)
943
{
944
  struct temp_slot *p, *q, *next, *next_q;
945
  int num_slots;
946
 
947
  /* We can't combine slots, because the information about which slot
948
     is in which alias set will be lost.  */
949
  if (flag_strict_aliasing)
950
    return;
951
 
952
  /* If there are a lot of temp slots, don't do anything unless
953
     high levels of optimization.  */
954
  if (! flag_expensive_optimizations)
955
    for (p = avail_temp_slots, num_slots = 0; p; p = p->next, num_slots++)
956
      if (num_slots > 100 || (num_slots > 10 && optimize == 0))
957
        return;
958
 
959
  for (p = avail_temp_slots; p; p = next)
960
    {
961
      int delete_p = 0;
962
 
963
      next = p->next;
964
 
965
      if (GET_MODE (p->slot) != BLKmode)
966
        continue;
967
 
968
      for (q = p->next; q; q = next_q)
969
        {
970
          int delete_q = 0;
971
 
972
          next_q = q->next;
973
 
974
          if (GET_MODE (q->slot) != BLKmode)
975
            continue;
976
 
977
          if (p->base_offset + p->full_size == q->base_offset)
978
            {
979
              /* Q comes after P; combine Q into P.  */
980
              p->size += q->size;
981
              p->full_size += q->full_size;
982
              delete_q = 1;
983
            }
984
          else if (q->base_offset + q->full_size == p->base_offset)
985
            {
986
              /* P comes after Q; combine P into Q.  */
987
              q->size += p->size;
988
              q->full_size += p->full_size;
989
              delete_p = 1;
990
              break;
991
            }
992
          if (delete_q)
993
            cut_slot_from_list (q, &avail_temp_slots);
994
        }
995
 
996
      /* Either delete P or advance past it.  */
997
      if (delete_p)
998
        cut_slot_from_list (p, &avail_temp_slots);
999
    }
1000
}
1001
 
1002
/* Indicate that NEW_RTX is an alternate way of referring to the temp
1003
   slot that previously was known by OLD_RTX.  */
1004
 
1005
void
1006
update_temp_slot_address (rtx old_rtx, rtx new_rtx)
1007
{
1008
  struct temp_slot *p;
1009
 
1010
  if (rtx_equal_p (old_rtx, new_rtx))
1011
    return;
1012
 
1013
  p = find_temp_slot_from_address (old_rtx);
1014
 
1015
  /* If we didn't find one, see if both OLD_RTX is a PLUS.  If so, and
1016
     NEW_RTX is a register, see if one operand of the PLUS is a
1017
     temporary location.  If so, NEW_RTX points into it.  Otherwise,
1018
     if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1019
     in common between them.  If so, try a recursive call on those
1020
     values.  */
1021
  if (p == 0)
1022
    {
1023
      if (GET_CODE (old_rtx) != PLUS)
1024
        return;
1025
 
1026
      if (REG_P (new_rtx))
1027
        {
1028
          update_temp_slot_address (XEXP (old_rtx, 0), new_rtx);
1029
          update_temp_slot_address (XEXP (old_rtx, 1), new_rtx);
1030
          return;
1031
        }
1032
      else if (GET_CODE (new_rtx) != PLUS)
1033
        return;
1034
 
1035
      if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 0)))
1036
        update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 1));
1037
      else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 0)))
1038
        update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 1));
1039
      else if (rtx_equal_p (XEXP (old_rtx, 0), XEXP (new_rtx, 1)))
1040
        update_temp_slot_address (XEXP (old_rtx, 1), XEXP (new_rtx, 0));
1041
      else if (rtx_equal_p (XEXP (old_rtx, 1), XEXP (new_rtx, 1)))
1042
        update_temp_slot_address (XEXP (old_rtx, 0), XEXP (new_rtx, 0));
1043
 
1044
      return;
1045
    }
1046
 
1047
  /* Otherwise add an alias for the temp's address.  */
1048
  insert_temp_slot_address (new_rtx, p);
1049
}
1050
 
1051
/* If X could be a reference to a temporary slot, mark the fact that its
1052
   address was taken.  */
1053
 
1054
void
1055
mark_temp_addr_taken (rtx x)
1056
{
1057
  struct temp_slot *p;
1058
 
1059
  if (x == 0)
1060
    return;
1061
 
1062
  /* If X is not in memory or is at a constant address, it cannot be in
1063
     a temporary slot.  */
1064
  if (!MEM_P (x) || CONSTANT_P (XEXP (x, 0)))
1065
    return;
1066
 
1067
  p = find_temp_slot_from_address (XEXP (x, 0));
1068
  if (p != 0)
1069
    p->addr_taken = 1;
1070
}
1071
 
1072
/* If X could be a reference to a temporary slot, mark that slot as
1073
   belonging to the to one level higher than the current level.  If X
1074
   matched one of our slots, just mark that one.  Otherwise, we can't
1075
   easily predict which it is, so upgrade all of them.  Kept slots
1076
   need not be touched.
1077
 
1078
   This is called when an ({...}) construct occurs and a statement
1079
   returns a value in memory.  */
1080
 
1081
void
1082
preserve_temp_slots (rtx x)
1083
{
1084
  struct temp_slot *p = 0, *next;
1085
 
1086
  /* If there is no result, we still might have some objects whose address
1087
     were taken, so we need to make sure they stay around.  */
1088
  if (x == 0)
1089
    {
1090
      for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1091
        {
1092
          next = p->next;
1093
 
1094
          if (p->addr_taken)
1095
            move_slot_to_level (p, temp_slot_level - 1);
1096
        }
1097
 
1098
      return;
1099
    }
1100
 
1101
  /* If X is a register that is being used as a pointer, see if we have
1102
     a temporary slot we know it points to.  To be consistent with
1103
     the code below, we really should preserve all non-kept slots
1104
     if we can't find a match, but that seems to be much too costly.  */
1105
  if (REG_P (x) && REG_POINTER (x))
1106
    p = find_temp_slot_from_address (x);
1107
 
1108
  /* If X is not in memory or is at a constant address, it cannot be in
1109
     a temporary slot, but it can contain something whose address was
1110
     taken.  */
1111
  if (p == 0 && (!MEM_P (x) || CONSTANT_P (XEXP (x, 0))))
1112
    {
1113
      for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1114
        {
1115
          next = p->next;
1116
 
1117
          if (p->addr_taken)
1118
            move_slot_to_level (p, temp_slot_level - 1);
1119
        }
1120
 
1121
      return;
1122
    }
1123
 
1124
  /* First see if we can find a match.  */
1125
  if (p == 0)
1126
    p = find_temp_slot_from_address (XEXP (x, 0));
1127
 
1128
  if (p != 0)
1129
    {
1130
      /* Move everything at our level whose address was taken to our new
1131
         level in case we used its address.  */
1132
      struct temp_slot *q;
1133
 
1134
      if (p->level == temp_slot_level)
1135
        {
1136
          for (q = *temp_slots_at_level (temp_slot_level); q; q = next)
1137
            {
1138
              next = q->next;
1139
 
1140
              if (p != q && q->addr_taken)
1141
                move_slot_to_level (q, temp_slot_level - 1);
1142
            }
1143
 
1144
          move_slot_to_level (p, temp_slot_level - 1);
1145
          p->addr_taken = 0;
1146
        }
1147
      return;
1148
    }
1149
 
1150
  /* Otherwise, preserve all non-kept slots at this level.  */
1151
  for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1152
    {
1153
      next = p->next;
1154
 
1155
      if (!p->keep)
1156
        move_slot_to_level (p, temp_slot_level - 1);
1157
    }
1158
}
1159
 
1160
/* Free all temporaries used so far.  This is normally called at the
1161
   end of generating code for a statement.  */
1162
 
1163
void
1164
free_temp_slots (void)
1165
{
1166
  struct temp_slot *p, *next;
1167
  bool some_available = false;
1168
 
1169
  for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1170
    {
1171
      next = p->next;
1172
 
1173
      if (!p->keep)
1174
        {
1175
          make_slot_available (p);
1176
          some_available = true;
1177
        }
1178
    }
1179
 
1180
  if (some_available)
1181
    {
1182
      remove_unused_temp_slot_addresses ();
1183
      combine_temp_slots ();
1184
    }
1185
}
1186
 
1187
/* Push deeper into the nesting level for stack temporaries.  */
1188
 
1189
void
1190
push_temp_slots (void)
1191
{
1192
  temp_slot_level++;
1193
}
1194
 
1195
/* Pop a temporary nesting level.  All slots in use in the current level
1196
   are freed.  */
1197
 
1198
void
1199
pop_temp_slots (void)
1200
{
1201
  struct temp_slot *p, *next;
1202
  bool some_available = false;
1203
 
1204
  for (p = *temp_slots_at_level (temp_slot_level); p; p = next)
1205
    {
1206
      next = p->next;
1207
      make_slot_available (p);
1208
      some_available = true;
1209
    }
1210
 
1211
  if (some_available)
1212
    {
1213
      remove_unused_temp_slot_addresses ();
1214
      combine_temp_slots ();
1215
    }
1216
 
1217
  temp_slot_level--;
1218
}
1219
 
1220
/* Initialize temporary slots.  */
1221
 
1222
void
1223
init_temp_slots (void)
1224
{
1225
  /* We have not allocated any temporaries yet.  */
1226
  avail_temp_slots = 0;
1227
  used_temp_slots = 0;
1228
  temp_slot_level = 0;
1229
 
1230
  /* Set up the table to map addresses to temp slots.  */
1231
  if (! temp_slot_address_table)
1232
    temp_slot_address_table = htab_create_ggc (32,
1233
                                               temp_slot_address_hash,
1234
                                               temp_slot_address_eq,
1235
                                               NULL);
1236
  else
1237
    htab_empty (temp_slot_address_table);
1238
}
1239
 
1240
/* These routines are responsible for converting virtual register references
1241
   to the actual hard register references once RTL generation is complete.
1242
 
1243
   The following four variables are used for communication between the
1244
   routines.  They contain the offsets of the virtual registers from their
1245
   respective hard registers.  */
1246
 
1247
static int in_arg_offset;
1248
static int var_offset;
1249
static int dynamic_offset;
1250
static int out_arg_offset;
1251
static int cfa_offset;
1252
 
1253
/* In most machines, the stack pointer register is equivalent to the bottom
1254
   of the stack.  */
1255
 
1256
#ifndef STACK_POINTER_OFFSET
1257
#define STACK_POINTER_OFFSET    0
1258
#endif
1259
 
1260
/* If not defined, pick an appropriate default for the offset of dynamically
1261
   allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1262
   REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE.  */
1263
 
1264
#ifndef STACK_DYNAMIC_OFFSET
1265
 
1266
/* The bottom of the stack points to the actual arguments.  If
1267
   REG_PARM_STACK_SPACE is defined, this includes the space for the register
1268
   parameters.  However, if OUTGOING_REG_PARM_STACK space is not defined,
1269
   stack space for register parameters is not pushed by the caller, but
1270
   rather part of the fixed stack areas and hence not included in
1271
   `crtl->outgoing_args_size'.  Nevertheless, we must allow
1272
   for it when allocating stack dynamic objects.  */
1273
 
1274
#if defined(REG_PARM_STACK_SPACE)
1275
#define STACK_DYNAMIC_OFFSET(FNDECL)    \
1276
((ACCUMULATE_OUTGOING_ARGS                                                    \
1277
  ? (crtl->outgoing_args_size                                 \
1278
     + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1279
                                               : REG_PARM_STACK_SPACE (FNDECL))) \
1280
  : 0) + (STACK_POINTER_OFFSET))
1281
#else
1282
#define STACK_DYNAMIC_OFFSET(FNDECL)    \
1283
((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0)             \
1284
 + (STACK_POINTER_OFFSET))
1285
#endif
1286
#endif
1287
 
1288
 
1289
/* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1290
   is a virtual register, return the equivalent hard register and set the
1291
   offset indirectly through the pointer.  Otherwise, return 0.  */
1292
 
1293
static rtx
1294
instantiate_new_reg (rtx x, HOST_WIDE_INT *poffset)
1295
{
1296
  rtx new_rtx;
1297
  HOST_WIDE_INT offset;
1298
 
1299
  if (x == virtual_incoming_args_rtx)
1300
    {
1301
      if (stack_realign_drap)
1302
        {
1303
          /* Replace virtual_incoming_args_rtx with internal arg
1304
             pointer if DRAP is used to realign stack.  */
1305
          new_rtx = crtl->args.internal_arg_pointer;
1306
          offset = 0;
1307
        }
1308
      else
1309
        new_rtx = arg_pointer_rtx, offset = in_arg_offset;
1310
    }
1311
  else if (x == virtual_stack_vars_rtx)
1312
    new_rtx = frame_pointer_rtx, offset = var_offset;
1313
  else if (x == virtual_stack_dynamic_rtx)
1314
    new_rtx = stack_pointer_rtx, offset = dynamic_offset;
1315
  else if (x == virtual_outgoing_args_rtx)
1316
    new_rtx = stack_pointer_rtx, offset = out_arg_offset;
1317
  else if (x == virtual_cfa_rtx)
1318
    {
1319
#ifdef FRAME_POINTER_CFA_OFFSET
1320
      new_rtx = frame_pointer_rtx;
1321
#else
1322
      new_rtx = arg_pointer_rtx;
1323
#endif
1324
      offset = cfa_offset;
1325
    }
1326
  else
1327
    return NULL_RTX;
1328
 
1329
  *poffset = offset;
1330
  return new_rtx;
1331
}
1332
 
1333
/* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1334
   Instantiate any virtual registers present inside of *LOC.  The expression
1335
   is simplified, as much as possible, but is not to be considered "valid"
1336
   in any sense implied by the target.  If any change is made, set CHANGED
1337
   to true.  */
1338
 
1339
static int
1340
instantiate_virtual_regs_in_rtx (rtx *loc, void *data)
1341
{
1342
  HOST_WIDE_INT offset;
1343
  bool *changed = (bool *) data;
1344
  rtx x, new_rtx;
1345
 
1346
  x = *loc;
1347
  if (x == 0)
1348
    return 0;
1349
 
1350
  switch (GET_CODE (x))
1351
    {
1352
    case REG:
1353
      new_rtx = instantiate_new_reg (x, &offset);
1354
      if (new_rtx)
1355
        {
1356
          *loc = plus_constant (new_rtx, offset);
1357
          if (changed)
1358
            *changed = true;
1359
        }
1360
      return -1;
1361
 
1362
    case PLUS:
1363
      new_rtx = instantiate_new_reg (XEXP (x, 0), &offset);
1364
      if (new_rtx)
1365
        {
1366
          new_rtx = plus_constant (new_rtx, offset);
1367
          *loc = simplify_gen_binary (PLUS, GET_MODE (x), new_rtx, XEXP (x, 1));
1368
          if (changed)
1369
            *changed = true;
1370
          return -1;
1371
        }
1372
 
1373
      /* FIXME -- from old code */
1374
          /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1375
             we can commute the PLUS and SUBREG because pointers into the
1376
             frame are well-behaved.  */
1377
      break;
1378
 
1379
    default:
1380
      break;
1381
    }
1382
 
1383
  return 0;
1384
}
1385
 
1386
/* A subroutine of instantiate_virtual_regs_in_insn.  Return true if X
1387
   matches the predicate for insn CODE operand OPERAND.  */
1388
 
1389
static int
1390
safe_insn_predicate (int code, int operand, rtx x)
1391
{
1392
  const struct insn_operand_data *op_data;
1393
 
1394
  if (code < 0)
1395
    return true;
1396
 
1397
  op_data = &insn_data[code].operand[operand];
1398
  if (op_data->predicate == NULL)
1399
    return true;
1400
 
1401
  return op_data->predicate (x, op_data->mode);
1402
}
1403
 
1404
/* A subroutine of instantiate_virtual_regs.  Instantiate any virtual
1405
   registers present inside of insn.  The result will be a valid insn.  */
1406
 
1407
static void
1408
instantiate_virtual_regs_in_insn (rtx insn)
1409
{
1410
  HOST_WIDE_INT offset;
1411
  int insn_code, i;
1412
  bool any_change = false;
1413
  rtx set, new_rtx, x, seq;
1414
 
1415
  /* There are some special cases to be handled first.  */
1416
  set = single_set (insn);
1417
  if (set)
1418
    {
1419
      /* We're allowed to assign to a virtual register.  This is interpreted
1420
         to mean that the underlying register gets assigned the inverse
1421
         transformation.  This is used, for example, in the handling of
1422
         non-local gotos.  */
1423
      new_rtx = instantiate_new_reg (SET_DEST (set), &offset);
1424
      if (new_rtx)
1425
        {
1426
          start_sequence ();
1427
 
1428
          for_each_rtx (&SET_SRC (set), instantiate_virtual_regs_in_rtx, NULL);
1429
          x = simplify_gen_binary (PLUS, GET_MODE (new_rtx), SET_SRC (set),
1430
                                   GEN_INT (-offset));
1431
          x = force_operand (x, new_rtx);
1432
          if (x != new_rtx)
1433
            emit_move_insn (new_rtx, x);
1434
 
1435
          seq = get_insns ();
1436
          end_sequence ();
1437
 
1438
          emit_insn_before (seq, insn);
1439
          delete_insn (insn);
1440
          return;
1441
        }
1442
 
1443
      /* Handle a straight copy from a virtual register by generating a
1444
         new add insn.  The difference between this and falling through
1445
         to the generic case is avoiding a new pseudo and eliminating a
1446
         move insn in the initial rtl stream.  */
1447
      new_rtx = instantiate_new_reg (SET_SRC (set), &offset);
1448
      if (new_rtx && offset != 0
1449
          && REG_P (SET_DEST (set))
1450
          && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1451
        {
1452
          start_sequence ();
1453
 
1454
          x = expand_simple_binop (GET_MODE (SET_DEST (set)), PLUS,
1455
                                   new_rtx, GEN_INT (offset), SET_DEST (set),
1456
                                   1, OPTAB_LIB_WIDEN);
1457
          if (x != SET_DEST (set))
1458
            emit_move_insn (SET_DEST (set), x);
1459
 
1460
          seq = get_insns ();
1461
          end_sequence ();
1462
 
1463
          emit_insn_before (seq, insn);
1464
          delete_insn (insn);
1465
          return;
1466
        }
1467
 
1468
      extract_insn (insn);
1469
      insn_code = INSN_CODE (insn);
1470
 
1471
      /* Handle a plus involving a virtual register by determining if the
1472
         operands remain valid if they're modified in place.  */
1473
      if (GET_CODE (SET_SRC (set)) == PLUS
1474
          && recog_data.n_operands >= 3
1475
          && recog_data.operand_loc[1] == &XEXP (SET_SRC (set), 0)
1476
          && recog_data.operand_loc[2] == &XEXP (SET_SRC (set), 1)
1477
          && CONST_INT_P (recog_data.operand[2])
1478
          && (new_rtx = instantiate_new_reg (recog_data.operand[1], &offset)))
1479
        {
1480
          offset += INTVAL (recog_data.operand[2]);
1481
 
1482
          /* If the sum is zero, then replace with a plain move.  */
1483
          if (offset == 0
1484
              && REG_P (SET_DEST (set))
1485
              && REGNO (SET_DEST (set)) > LAST_VIRTUAL_REGISTER)
1486
            {
1487
              start_sequence ();
1488
              emit_move_insn (SET_DEST (set), new_rtx);
1489
              seq = get_insns ();
1490
              end_sequence ();
1491
 
1492
              emit_insn_before (seq, insn);
1493
              delete_insn (insn);
1494
              return;
1495
            }
1496
 
1497
          x = gen_int_mode (offset, recog_data.operand_mode[2]);
1498
 
1499
          /* Using validate_change and apply_change_group here leaves
1500
             recog_data in an invalid state.  Since we know exactly what
1501
             we want to check, do those two by hand.  */
1502
          if (safe_insn_predicate (insn_code, 1, new_rtx)
1503
              && safe_insn_predicate (insn_code, 2, x))
1504
            {
1505
              *recog_data.operand_loc[1] = recog_data.operand[1] = new_rtx;
1506
              *recog_data.operand_loc[2] = recog_data.operand[2] = x;
1507
              any_change = true;
1508
 
1509
              /* Fall through into the regular operand fixup loop in
1510
                 order to take care of operands other than 1 and 2.  */
1511
            }
1512
        }
1513
    }
1514
  else
1515
    {
1516
      extract_insn (insn);
1517
      insn_code = INSN_CODE (insn);
1518
    }
1519
 
1520
  /* In the general case, we expect virtual registers to appear only in
1521
     operands, and then only as either bare registers or inside memories.  */
1522
  for (i = 0; i < recog_data.n_operands; ++i)
1523
    {
1524
      x = recog_data.operand[i];
1525
      switch (GET_CODE (x))
1526
        {
1527
        case MEM:
1528
          {
1529
            rtx addr = XEXP (x, 0);
1530
            bool changed = false;
1531
 
1532
            for_each_rtx (&addr, instantiate_virtual_regs_in_rtx, &changed);
1533
            if (!changed)
1534
              continue;
1535
 
1536
            start_sequence ();
1537
            x = replace_equiv_address (x, addr);
1538
            /* It may happen that the address with the virtual reg
1539
               was valid (e.g. based on the virtual stack reg, which might
1540
               be acceptable to the predicates with all offsets), whereas
1541
               the address now isn't anymore, for instance when the address
1542
               is still offsetted, but the base reg isn't virtual-stack-reg
1543
               anymore.  Below we would do a force_reg on the whole operand,
1544
               but this insn might actually only accept memory.  Hence,
1545
               before doing that last resort, try to reload the address into
1546
               a register, so this operand stays a MEM.  */
1547
            if (!safe_insn_predicate (insn_code, i, x))
1548
              {
1549
                addr = force_reg (GET_MODE (addr), addr);
1550
                x = replace_equiv_address (x, addr);
1551
              }
1552
            seq = get_insns ();
1553
            end_sequence ();
1554
            if (seq)
1555
              emit_insn_before (seq, insn);
1556
          }
1557
          break;
1558
 
1559
        case REG:
1560
          new_rtx = instantiate_new_reg (x, &offset);
1561
          if (new_rtx == NULL)
1562
            continue;
1563
          if (offset == 0)
1564
            x = new_rtx;
1565
          else
1566
            {
1567
              start_sequence ();
1568
 
1569
              /* Careful, special mode predicates may have stuff in
1570
                 insn_data[insn_code].operand[i].mode that isn't useful
1571
                 to us for computing a new value.  */
1572
              /* ??? Recognize address_operand and/or "p" constraints
1573
                 to see if (plus new offset) is a valid before we put
1574
                 this through expand_simple_binop.  */
1575
              x = expand_simple_binop (GET_MODE (x), PLUS, new_rtx,
1576
                                       GEN_INT (offset), NULL_RTX,
1577
                                       1, OPTAB_LIB_WIDEN);
1578
              seq = get_insns ();
1579
              end_sequence ();
1580
              emit_insn_before (seq, insn);
1581
            }
1582
          break;
1583
 
1584
        case SUBREG:
1585
          new_rtx = instantiate_new_reg (SUBREG_REG (x), &offset);
1586
          if (new_rtx == NULL)
1587
            continue;
1588
          if (offset != 0)
1589
            {
1590
              start_sequence ();
1591
              new_rtx = expand_simple_binop (GET_MODE (new_rtx), PLUS, new_rtx,
1592
                                         GEN_INT (offset), NULL_RTX,
1593
                                         1, OPTAB_LIB_WIDEN);
1594
              seq = get_insns ();
1595
              end_sequence ();
1596
              emit_insn_before (seq, insn);
1597
            }
1598
          x = simplify_gen_subreg (recog_data.operand_mode[i], new_rtx,
1599
                                   GET_MODE (new_rtx), SUBREG_BYTE (x));
1600
          gcc_assert (x);
1601
          break;
1602
 
1603
        default:
1604
          continue;
1605
        }
1606
 
1607
      /* At this point, X contains the new value for the operand.
1608
         Validate the new value vs the insn predicate.  Note that
1609
         asm insns will have insn_code -1 here.  */
1610
      if (!safe_insn_predicate (insn_code, i, x))
1611
        {
1612
          start_sequence ();
1613
          if (REG_P (x))
1614
            {
1615
              gcc_assert (REGNO (x) <= LAST_VIRTUAL_REGISTER);
1616
              x = copy_to_reg (x);
1617
            }
1618
          else
1619
            x = force_reg (insn_data[insn_code].operand[i].mode, x);
1620
          seq = get_insns ();
1621
          end_sequence ();
1622
          if (seq)
1623
            emit_insn_before (seq, insn);
1624
        }
1625
 
1626
      *recog_data.operand_loc[i] = recog_data.operand[i] = x;
1627
      any_change = true;
1628
    }
1629
 
1630
  if (any_change)
1631
    {
1632
      /* Propagate operand changes into the duplicates.  */
1633
      for (i = 0; i < recog_data.n_dups; ++i)
1634
        *recog_data.dup_loc[i]
1635
          = copy_rtx (recog_data.operand[(unsigned)recog_data.dup_num[i]]);
1636
 
1637
      /* Force re-recognition of the instruction for validation.  */
1638
      INSN_CODE (insn) = -1;
1639
    }
1640
 
1641
  if (asm_noperands (PATTERN (insn)) >= 0)
1642
    {
1643
      if (!check_asm_operands (PATTERN (insn)))
1644
        {
1645
          error_for_asm (insn, "impossible constraint in %<asm%>");
1646
          delete_insn (insn);
1647
        }
1648
    }
1649
  else
1650
    {
1651
      if (recog_memoized (insn) < 0)
1652
        fatal_insn_not_found (insn);
1653
    }
1654
}
1655
 
1656
/* Subroutine of instantiate_decls.  Given RTL representing a decl,
1657
   do any instantiation required.  */
1658
 
1659
void
1660
instantiate_decl_rtl (rtx x)
1661
{
1662
  rtx addr;
1663
 
1664
  if (x == 0)
1665
    return;
1666
 
1667
  /* If this is a CONCAT, recurse for the pieces.  */
1668
  if (GET_CODE (x) == CONCAT)
1669
    {
1670
      instantiate_decl_rtl (XEXP (x, 0));
1671
      instantiate_decl_rtl (XEXP (x, 1));
1672
      return;
1673
    }
1674
 
1675
  /* If this is not a MEM, no need to do anything.  Similarly if the
1676
     address is a constant or a register that is not a virtual register.  */
1677
  if (!MEM_P (x))
1678
    return;
1679
 
1680
  addr = XEXP (x, 0);
1681
  if (CONSTANT_P (addr)
1682
      || (REG_P (addr)
1683
          && (REGNO (addr) < FIRST_VIRTUAL_REGISTER
1684
              || REGNO (addr) > LAST_VIRTUAL_REGISTER)))
1685
    return;
1686
 
1687
  for_each_rtx (&XEXP (x, 0), instantiate_virtual_regs_in_rtx, NULL);
1688
}
1689
 
1690
/* Helper for instantiate_decls called via walk_tree: Process all decls
1691
   in the given DECL_VALUE_EXPR.  */
1692
 
1693
static tree
1694
instantiate_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
1695
{
1696
  tree t = *tp;
1697
  if (! EXPR_P (t))
1698
    {
1699
      *walk_subtrees = 0;
1700
      if (DECL_P (t) && DECL_RTL_SET_P (t))
1701
        instantiate_decl_rtl (DECL_RTL (t));
1702
    }
1703
  return NULL;
1704
}
1705
 
1706
/* Subroutine of instantiate_decls: Process all decls in the given
1707
   BLOCK node and all its subblocks.  */
1708
 
1709
static void
1710
instantiate_decls_1 (tree let)
1711
{
1712
  tree t;
1713
 
1714
  for (t = BLOCK_VARS (let); t; t = TREE_CHAIN (t))
1715
    {
1716
      if (DECL_RTL_SET_P (t))
1717
        instantiate_decl_rtl (DECL_RTL (t));
1718
      if (TREE_CODE (t) == VAR_DECL && DECL_HAS_VALUE_EXPR_P (t))
1719
        {
1720
          tree v = DECL_VALUE_EXPR (t);
1721
          walk_tree (&v, instantiate_expr, NULL, NULL);
1722
        }
1723
    }
1724
 
1725
  /* Process all subblocks.  */
1726
  for (t = BLOCK_SUBBLOCKS (let); t; t = BLOCK_CHAIN (t))
1727
    instantiate_decls_1 (t);
1728
}
1729
 
1730
/* Scan all decls in FNDECL (both variables and parameters) and instantiate
1731
   all virtual registers in their DECL_RTL's.  */
1732
 
1733
static void
1734
instantiate_decls (tree fndecl)
1735
{
1736
  tree decl, t, next;
1737
 
1738
  /* Process all parameters of the function.  */
1739
  for (decl = DECL_ARGUMENTS (fndecl); decl; decl = TREE_CHAIN (decl))
1740
    {
1741
      instantiate_decl_rtl (DECL_RTL (decl));
1742
      instantiate_decl_rtl (DECL_INCOMING_RTL (decl));
1743
      if (DECL_HAS_VALUE_EXPR_P (decl))
1744
        {
1745
          tree v = DECL_VALUE_EXPR (decl);
1746
          walk_tree (&v, instantiate_expr, NULL, NULL);
1747
        }
1748
    }
1749
 
1750
  /* Now process all variables defined in the function or its subblocks.  */
1751
  instantiate_decls_1 (DECL_INITIAL (fndecl));
1752
 
1753
  t = cfun->local_decls;
1754
  cfun->local_decls = NULL_TREE;
1755
  for (; t; t = next)
1756
    {
1757
      next = TREE_CHAIN (t);
1758
      decl = TREE_VALUE (t);
1759
      if (DECL_RTL_SET_P (decl))
1760
        instantiate_decl_rtl (DECL_RTL (decl));
1761
      ggc_free (t);
1762
    }
1763
}
1764
 
1765
/* Pass through the INSNS of function FNDECL and convert virtual register
1766
   references to hard register references.  */
1767
 
1768
static unsigned int
1769
instantiate_virtual_regs (void)
1770
{
1771
  rtx insn;
1772
 
1773
  /* Compute the offsets to use for this function.  */
1774
  in_arg_offset = FIRST_PARM_OFFSET (current_function_decl);
1775
  var_offset = STARTING_FRAME_OFFSET;
1776
  dynamic_offset = STACK_DYNAMIC_OFFSET (current_function_decl);
1777
  out_arg_offset = STACK_POINTER_OFFSET;
1778
#ifdef FRAME_POINTER_CFA_OFFSET
1779
  cfa_offset = FRAME_POINTER_CFA_OFFSET (current_function_decl);
1780
#else
1781
  cfa_offset = ARG_POINTER_CFA_OFFSET (current_function_decl);
1782
#endif
1783
 
1784
  /* Initialize recognition, indicating that volatile is OK.  */
1785
  init_recog ();
1786
 
1787
  /* Scan through all the insns, instantiating every virtual register still
1788
     present.  */
1789
  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
1790
    if (INSN_P (insn))
1791
      {
1792
        /* These patterns in the instruction stream can never be recognized.
1793
           Fortunately, they shouldn't contain virtual registers either.  */
1794
        if (GET_CODE (PATTERN (insn)) == USE
1795
            || GET_CODE (PATTERN (insn)) == CLOBBER
1796
            || GET_CODE (PATTERN (insn)) == ADDR_VEC
1797
            || GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC
1798
            || GET_CODE (PATTERN (insn)) == ASM_INPUT)
1799
          continue;
1800
        else if (DEBUG_INSN_P (insn))
1801
          for_each_rtx (&INSN_VAR_LOCATION (insn),
1802
                        instantiate_virtual_regs_in_rtx, NULL);
1803
        else
1804
          instantiate_virtual_regs_in_insn (insn);
1805
 
1806
        if (INSN_DELETED_P (insn))
1807
          continue;
1808
 
1809
        for_each_rtx (&REG_NOTES (insn), instantiate_virtual_regs_in_rtx, NULL);
1810
 
1811
        /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE.  */
1812
        if (CALL_P (insn))
1813
          for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn),
1814
                        instantiate_virtual_regs_in_rtx, NULL);
1815
      }
1816
 
1817
  /* Instantiate the virtual registers in the DECLs for debugging purposes.  */
1818
  instantiate_decls (current_function_decl);
1819
 
1820
  targetm.instantiate_decls ();
1821
 
1822
  /* Indicate that, from now on, assign_stack_local should use
1823
     frame_pointer_rtx.  */
1824
  virtuals_instantiated = 1;
1825
  return 0;
1826
}
1827
 
1828
struct rtl_opt_pass pass_instantiate_virtual_regs =
1829
{
1830
 {
1831
  RTL_PASS,
1832
  "vregs",                              /* name */
1833
  NULL,                                 /* gate */
1834
  instantiate_virtual_regs,             /* execute */
1835
  NULL,                                 /* sub */
1836
  NULL,                                 /* next */
1837
  0,                                    /* static_pass_number */
1838
  TV_NONE,                              /* tv_id */
1839
  0,                                    /* properties_required */
1840
  0,                                    /* properties_provided */
1841
  0,                                    /* properties_destroyed */
1842
  0,                                    /* todo_flags_start */
1843
  TODO_dump_func                        /* todo_flags_finish */
1844
 }
1845
};
1846
 
1847
 
1848
/* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1849
   This means a type for which function calls must pass an address to the
1850
   function or get an address back from the function.
1851
   EXP may be a type node or an expression (whose type is tested).  */
1852
 
1853
int
1854
aggregate_value_p (const_tree exp, const_tree fntype)
1855
{
1856
  int i, regno, nregs;
1857
  rtx reg;
1858
 
1859
  const_tree type = (TYPE_P (exp)) ? exp : TREE_TYPE (exp);
1860
 
1861
  /* DECL node associated with FNTYPE when relevant, which we might need to
1862
     check for by-invisible-reference returns, typically for CALL_EXPR input
1863
     EXPressions.  */
1864
  const_tree fndecl = NULL_TREE;
1865
 
1866
  if (fntype)
1867
    switch (TREE_CODE (fntype))
1868
      {
1869
      case CALL_EXPR:
1870
        fndecl = get_callee_fndecl (fntype);
1871
        fntype = (fndecl
1872
                  ? TREE_TYPE (fndecl)
1873
                  : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype))));
1874
        break;
1875
      case FUNCTION_DECL:
1876
        fndecl = fntype;
1877
        fntype = TREE_TYPE (fndecl);
1878
        break;
1879
      case FUNCTION_TYPE:
1880
      case METHOD_TYPE:
1881
        break;
1882
      case IDENTIFIER_NODE:
1883
        fntype = 0;
1884
        break;
1885
      default:
1886
        /* We don't expect other rtl types here.  */
1887
        gcc_unreachable ();
1888
      }
1889
 
1890
  if (TREE_CODE (type) == VOID_TYPE)
1891
    return 0;
1892
 
1893
  /* If a record should be passed the same as its first (and only) member
1894
     don't pass it as an aggregate.  */
1895
  if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
1896
    return aggregate_value_p (first_field (type), fntype);
1897
 
1898
  /* If the front end has decided that this needs to be passed by
1899
     reference, do so.  */
1900
  if ((TREE_CODE (exp) == PARM_DECL || TREE_CODE (exp) == RESULT_DECL)
1901
      && DECL_BY_REFERENCE (exp))
1902
    return 1;
1903
 
1904
  /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1905
     called function RESULT_DECL, meaning the function returns in memory by
1906
     invisible reference.  This check lets front-ends not set TREE_ADDRESSABLE
1907
     on the function type, which used to be the way to request such a return
1908
     mechanism but might now be causing troubles at gimplification time if
1909
     temporaries with the function type need to be created.  */
1910
  if (TREE_CODE (exp) == CALL_EXPR && fndecl && DECL_RESULT (fndecl)
1911
      && DECL_BY_REFERENCE (DECL_RESULT (fndecl)))
1912
    return 1;
1913
 
1914
  if (targetm.calls.return_in_memory (type, fntype))
1915
    return 1;
1916
  /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1917
     and thus can't be returned in registers.  */
1918
  if (TREE_ADDRESSABLE (type))
1919
    return 1;
1920
  if (flag_pcc_struct_return && AGGREGATE_TYPE_P (type))
1921
    return 1;
1922
  /* Make sure we have suitable call-clobbered regs to return
1923
     the value in; if not, we must return it in memory.  */
1924
  reg = hard_function_value (type, 0, fntype, 0);
1925
 
1926
  /* If we have something other than a REG (e.g. a PARALLEL), then assume
1927
     it is OK.  */
1928
  if (!REG_P (reg))
1929
    return 0;
1930
 
1931
  regno = REGNO (reg);
1932
  nregs = hard_regno_nregs[regno][TYPE_MODE (type)];
1933
  for (i = 0; i < nregs; i++)
1934
    if (! call_used_regs[regno + i])
1935
      return 1;
1936
  return 0;
1937
}
1938
 
1939
/* Return true if we should assign DECL a pseudo register; false if it
1940
   should live on the local stack.  */
1941
 
1942
bool
1943
use_register_for_decl (const_tree decl)
1944
{
1945
  if (!targetm.calls.allocate_stack_slots_for_args())
1946
    return true;
1947
 
1948
  /* Honor volatile.  */
1949
  if (TREE_SIDE_EFFECTS (decl))
1950
    return false;
1951
 
1952
  /* Honor addressability.  */
1953
  if (TREE_ADDRESSABLE (decl))
1954
    return false;
1955
 
1956
  /* Only register-like things go in registers.  */
1957
  if (DECL_MODE (decl) == BLKmode)
1958
    return false;
1959
 
1960
  /* If -ffloat-store specified, don't put explicit float variables
1961
     into registers.  */
1962
  /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1963
     propagates values across these stores, and it probably shouldn't.  */
1964
  if (flag_float_store && FLOAT_TYPE_P (TREE_TYPE (decl)))
1965
    return false;
1966
 
1967
  /* If we're not interested in tracking debugging information for
1968
     this decl, then we can certainly put it in a register.  */
1969
  if (DECL_IGNORED_P (decl))
1970
    return true;
1971
 
1972
  if (optimize)
1973
    return true;
1974
 
1975
  if (!DECL_REGISTER (decl))
1976
    return false;
1977
 
1978
  switch (TREE_CODE (TREE_TYPE (decl)))
1979
    {
1980
    case RECORD_TYPE:
1981
    case UNION_TYPE:
1982
    case QUAL_UNION_TYPE:
1983
      /* When not optimizing, disregard register keyword for variables with
1984
         types containing methods, otherwise the methods won't be callable
1985
         from the debugger.  */
1986
      if (TYPE_METHODS (TREE_TYPE (decl)))
1987
        return false;
1988
      break;
1989
    default:
1990
      break;
1991
    }
1992
 
1993
  return true;
1994
}
1995
 
1996
/* Return true if TYPE should be passed by invisible reference.  */
1997
 
1998
bool
1999
pass_by_reference (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2000
                   tree type, bool named_arg)
2001
{
2002
  if (type)
2003
    {
2004
      /* If this type contains non-trivial constructors, then it is
2005
         forbidden for the middle-end to create any new copies.  */
2006
      if (TREE_ADDRESSABLE (type))
2007
        return true;
2008
 
2009
      /* GCC post 3.4 passes *all* variable sized types by reference.  */
2010
      if (!TYPE_SIZE (type) || TREE_CODE (TYPE_SIZE (type)) != INTEGER_CST)
2011
        return true;
2012
 
2013
      /* If a record type should be passed the same as its first (and only)
2014
         member, use the type and mode of that member.  */
2015
      if (TREE_CODE (type) == RECORD_TYPE && TYPE_TRANSPARENT_AGGR (type))
2016
        {
2017
          type = TREE_TYPE (first_field (type));
2018
          mode = TYPE_MODE (type);
2019
        }
2020
    }
2021
 
2022
  return targetm.calls.pass_by_reference (ca, mode, type, named_arg);
2023
}
2024
 
2025
/* Return true if TYPE, which is passed by reference, should be callee
2026
   copied instead of caller copied.  */
2027
 
2028
bool
2029
reference_callee_copied (CUMULATIVE_ARGS *ca, enum machine_mode mode,
2030
                         tree type, bool named_arg)
2031
{
2032
  if (type && TREE_ADDRESSABLE (type))
2033
    return false;
2034
  return targetm.calls.callee_copies (ca, mode, type, named_arg);
2035
}
2036
 
2037
/* Structures to communicate between the subroutines of assign_parms.
2038
   The first holds data persistent across all parameters, the second
2039
   is cleared out for each parameter.  */
2040
 
2041
struct assign_parm_data_all
2042
{
2043
  CUMULATIVE_ARGS args_so_far;
2044
  struct args_size stack_args_size;
2045
  tree function_result_decl;
2046
  tree orig_fnargs;
2047
  rtx first_conversion_insn;
2048
  rtx last_conversion_insn;
2049
  HOST_WIDE_INT pretend_args_size;
2050
  HOST_WIDE_INT extra_pretend_bytes;
2051
  int reg_parm_stack_space;
2052
};
2053
 
2054
struct assign_parm_data_one
2055
{
2056
  tree nominal_type;
2057
  tree passed_type;
2058
  rtx entry_parm;
2059
  rtx stack_parm;
2060
  enum machine_mode nominal_mode;
2061
  enum machine_mode passed_mode;
2062
  enum machine_mode promoted_mode;
2063
  struct locate_and_pad_arg_data locate;
2064
  int partial;
2065
  BOOL_BITFIELD named_arg : 1;
2066
  BOOL_BITFIELD passed_pointer : 1;
2067
  BOOL_BITFIELD on_stack : 1;
2068
  BOOL_BITFIELD loaded_in_reg : 1;
2069
};
2070
 
2071
/* A subroutine of assign_parms.  Initialize ALL.  */
2072
 
2073
static void
2074
assign_parms_initialize_all (struct assign_parm_data_all *all)
2075
{
2076
  tree fntype;
2077
 
2078
  memset (all, 0, sizeof (*all));
2079
 
2080
  fntype = TREE_TYPE (current_function_decl);
2081
 
2082
#ifdef INIT_CUMULATIVE_INCOMING_ARGS
2083
  INIT_CUMULATIVE_INCOMING_ARGS (all->args_so_far, fntype, NULL_RTX);
2084
#else
2085
  INIT_CUMULATIVE_ARGS (all->args_so_far, fntype, NULL_RTX,
2086
                        current_function_decl, -1);
2087
#endif
2088
 
2089
#ifdef REG_PARM_STACK_SPACE
2090
  all->reg_parm_stack_space = REG_PARM_STACK_SPACE (current_function_decl);
2091
#endif
2092
}
2093
 
2094
/* If ARGS contains entries with complex types, split the entry into two
2095
   entries of the component type.  Return a new list of substitutions are
2096
   needed, else the old list.  */
2097
 
2098
static void
2099
split_complex_args (VEC(tree, heap) **args)
2100
{
2101
  unsigned i;
2102
  tree p;
2103
 
2104
  for (i = 0; VEC_iterate (tree, *args, i, p); ++i)
2105
    {
2106
      tree type = TREE_TYPE (p);
2107
      if (TREE_CODE (type) == COMPLEX_TYPE
2108
          && targetm.calls.split_complex_arg (type))
2109
        {
2110
          tree decl;
2111
          tree subtype = TREE_TYPE (type);
2112
          bool addressable = TREE_ADDRESSABLE (p);
2113
 
2114
          /* Rewrite the PARM_DECL's type with its component.  */
2115
          p = copy_node (p);
2116
          TREE_TYPE (p) = subtype;
2117
          DECL_ARG_TYPE (p) = TREE_TYPE (DECL_ARG_TYPE (p));
2118
          DECL_MODE (p) = VOIDmode;
2119
          DECL_SIZE (p) = NULL;
2120
          DECL_SIZE_UNIT (p) = NULL;
2121
          /* If this arg must go in memory, put it in a pseudo here.
2122
             We can't allow it to go in memory as per normal parms,
2123
             because the usual place might not have the imag part
2124
             adjacent to the real part.  */
2125
          DECL_ARTIFICIAL (p) = addressable;
2126
          DECL_IGNORED_P (p) = addressable;
2127
          TREE_ADDRESSABLE (p) = 0;
2128
          layout_decl (p, 0);
2129
          VEC_replace (tree, *args, i, p);
2130
 
2131
          /* Build a second synthetic decl.  */
2132
          decl = build_decl (EXPR_LOCATION (p),
2133
                             PARM_DECL, NULL_TREE, subtype);
2134
          DECL_ARG_TYPE (decl) = DECL_ARG_TYPE (p);
2135
          DECL_ARTIFICIAL (decl) = addressable;
2136
          DECL_IGNORED_P (decl) = addressable;
2137
          layout_decl (decl, 0);
2138
          VEC_safe_insert (tree, heap, *args, ++i, decl);
2139
        }
2140
    }
2141
}
2142
 
2143
/* A subroutine of assign_parms.  Adjust the parameter list to incorporate
2144
   the hidden struct return argument, and (abi willing) complex args.
2145
   Return the new parameter list.  */
2146
 
2147
static VEC(tree, heap) *
2148
assign_parms_augmented_arg_list (struct assign_parm_data_all *all)
2149
{
2150
  tree fndecl = current_function_decl;
2151
  tree fntype = TREE_TYPE (fndecl);
2152
  VEC(tree, heap) *fnargs = NULL;
2153
  tree arg;
2154
 
2155
  for (arg = DECL_ARGUMENTS (fndecl); arg; arg = TREE_CHAIN (arg))
2156
    VEC_safe_push (tree, heap, fnargs, arg);
2157
 
2158
  all->orig_fnargs = DECL_ARGUMENTS (fndecl);
2159
 
2160
  /* If struct value address is treated as the first argument, make it so.  */
2161
  if (aggregate_value_p (DECL_RESULT (fndecl), fndecl)
2162
      && ! cfun->returns_pcc_struct
2163
      && targetm.calls.struct_value_rtx (TREE_TYPE (fndecl), 1) == 0)
2164
    {
2165
      tree type = build_pointer_type (TREE_TYPE (fntype));
2166
      tree decl;
2167
 
2168
      decl = build_decl (DECL_SOURCE_LOCATION (fndecl),
2169
                         PARM_DECL, NULL_TREE, type);
2170
      DECL_ARG_TYPE (decl) = type;
2171
      DECL_ARTIFICIAL (decl) = 1;
2172
      DECL_IGNORED_P (decl) = 1;
2173
 
2174
      TREE_CHAIN (decl) = all->orig_fnargs;
2175
      all->orig_fnargs = decl;
2176
      VEC_safe_insert (tree, heap, fnargs, 0, decl);
2177
 
2178
      all->function_result_decl = decl;
2179
    }
2180
 
2181
  /* If the target wants to split complex arguments into scalars, do so.  */
2182
  if (targetm.calls.split_complex_arg)
2183
    split_complex_args (&fnargs);
2184
 
2185
  return fnargs;
2186
}
2187
 
2188
/* A subroutine of assign_parms.  Examine PARM and pull out type and mode
2189
   data for the parameter.  Incorporate ABI specifics such as pass-by-
2190
   reference and type promotion.  */
2191
 
2192
static void
2193
assign_parm_find_data_types (struct assign_parm_data_all *all, tree parm,
2194
                             struct assign_parm_data_one *data)
2195
{
2196
  tree nominal_type, passed_type;
2197
  enum machine_mode nominal_mode, passed_mode, promoted_mode;
2198
  int unsignedp;
2199
 
2200
  memset (data, 0, sizeof (*data));
2201
 
2202
  /* NAMED_ARG is a misnomer.  We really mean 'non-variadic'. */
2203
  if (!cfun->stdarg)
2204
    data->named_arg = 1;  /* No variadic parms.  */
2205
  else if (TREE_CHAIN (parm))
2206
    data->named_arg = 1;  /* Not the last non-variadic parm. */
2207
  else if (targetm.calls.strict_argument_naming (&all->args_so_far))
2208
    data->named_arg = 1;  /* Only variadic ones are unnamed.  */
2209
  else
2210
    data->named_arg = 0;  /* Treat as variadic.  */
2211
 
2212
  nominal_type = TREE_TYPE (parm);
2213
  passed_type = DECL_ARG_TYPE (parm);
2214
 
2215
  /* Look out for errors propagating this far.  Also, if the parameter's
2216
     type is void then its value doesn't matter.  */
2217
  if (TREE_TYPE (parm) == error_mark_node
2218
      /* This can happen after weird syntax errors
2219
         or if an enum type is defined among the parms.  */
2220
      || TREE_CODE (parm) != PARM_DECL
2221
      || passed_type == NULL
2222
      || VOID_TYPE_P (nominal_type))
2223
    {
2224
      nominal_type = passed_type = void_type_node;
2225
      nominal_mode = passed_mode = promoted_mode = VOIDmode;
2226
      goto egress;
2227
    }
2228
 
2229
  /* Find mode of arg as it is passed, and mode of arg as it should be
2230
     during execution of this function.  */
2231
  passed_mode = TYPE_MODE (passed_type);
2232
  nominal_mode = TYPE_MODE (nominal_type);
2233
 
2234
  /* If the parm is to be passed as a transparent union or record, use the
2235
     type of the first field for the tests below.  We have already verified
2236
     that the modes are the same.  */
2237
  if ((TREE_CODE (passed_type) == UNION_TYPE
2238
       || TREE_CODE (passed_type) == RECORD_TYPE)
2239
      && TYPE_TRANSPARENT_AGGR (passed_type))
2240
    passed_type = TREE_TYPE (first_field (passed_type));
2241
 
2242
  /* See if this arg was passed by invisible reference.  */
2243
  if (pass_by_reference (&all->args_so_far, passed_mode,
2244
                         passed_type, data->named_arg))
2245
    {
2246
      passed_type = nominal_type = build_pointer_type (passed_type);
2247
      data->passed_pointer = true;
2248
      passed_mode = nominal_mode = Pmode;
2249
    }
2250
 
2251
  /* Find mode as it is passed by the ABI.  */
2252
  unsignedp = TYPE_UNSIGNED (passed_type);
2253
  promoted_mode = promote_function_mode (passed_type, passed_mode, &unsignedp,
2254
                                         TREE_TYPE (current_function_decl), 0);
2255
 
2256
 egress:
2257
  data->nominal_type = nominal_type;
2258
  data->passed_type = passed_type;
2259
  data->nominal_mode = nominal_mode;
2260
  data->passed_mode = passed_mode;
2261
  data->promoted_mode = promoted_mode;
2262
}
2263
 
2264
/* A subroutine of assign_parms.  Invoke setup_incoming_varargs.  */
2265
 
2266
static void
2267
assign_parms_setup_varargs (struct assign_parm_data_all *all,
2268
                            struct assign_parm_data_one *data, bool no_rtl)
2269
{
2270
  int varargs_pretend_bytes = 0;
2271
 
2272
  targetm.calls.setup_incoming_varargs (&all->args_so_far,
2273
                                        data->promoted_mode,
2274
                                        data->passed_type,
2275
                                        &varargs_pretend_bytes, no_rtl);
2276
 
2277
  /* If the back-end has requested extra stack space, record how much is
2278
     needed.  Do not change pretend_args_size otherwise since it may be
2279
     nonzero from an earlier partial argument.  */
2280
  if (varargs_pretend_bytes > 0)
2281
    all->pretend_args_size = varargs_pretend_bytes;
2282
}
2283
 
2284
/* A subroutine of assign_parms.  Set DATA->ENTRY_PARM corresponding to
2285
   the incoming location of the current parameter.  */
2286
 
2287
static void
2288
assign_parm_find_entry_rtl (struct assign_parm_data_all *all,
2289
                            struct assign_parm_data_one *data)
2290
{
2291
  HOST_WIDE_INT pretend_bytes = 0;
2292
  rtx entry_parm;
2293
  bool in_regs;
2294
 
2295
  if (data->promoted_mode == VOIDmode)
2296
    {
2297
      data->entry_parm = data->stack_parm = const0_rtx;
2298
      return;
2299
    }
2300
 
2301
#ifdef FUNCTION_INCOMING_ARG
2302
  entry_parm = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2303
                                      data->passed_type, data->named_arg);
2304
#else
2305
  entry_parm = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2306
                             data->passed_type, data->named_arg);
2307
#endif
2308
 
2309
  if (entry_parm == 0)
2310
    data->promoted_mode = data->passed_mode;
2311
 
2312
  /* Determine parm's home in the stack, in case it arrives in the stack
2313
     or we should pretend it did.  Compute the stack position and rtx where
2314
     the argument arrives and its size.
2315
 
2316
     There is one complexity here:  If this was a parameter that would
2317
     have been passed in registers, but wasn't only because it is
2318
     __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2319
     it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2320
     In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2321
     as it was the previous time.  */
2322
  in_regs = entry_parm != 0;
2323
#ifdef STACK_PARMS_IN_REG_PARM_AREA
2324
  in_regs = true;
2325
#endif
2326
  if (!in_regs && !data->named_arg)
2327
    {
2328
      if (targetm.calls.pretend_outgoing_varargs_named (&all->args_so_far))
2329
        {
2330
          rtx tem;
2331
#ifdef FUNCTION_INCOMING_ARG
2332
          tem = FUNCTION_INCOMING_ARG (all->args_so_far, data->promoted_mode,
2333
                                       data->passed_type, true);
2334
#else
2335
          tem = FUNCTION_ARG (all->args_so_far, data->promoted_mode,
2336
                              data->passed_type, true);
2337
#endif
2338
          in_regs = tem != NULL;
2339
        }
2340
    }
2341
 
2342
  /* If this parameter was passed both in registers and in the stack, use
2343
     the copy on the stack.  */
2344
  if (targetm.calls.must_pass_in_stack (data->promoted_mode,
2345
                                        data->passed_type))
2346
    entry_parm = 0;
2347
 
2348
  if (entry_parm)
2349
    {
2350
      int partial;
2351
 
2352
      partial = targetm.calls.arg_partial_bytes (&all->args_so_far,
2353
                                                 data->promoted_mode,
2354
                                                 data->passed_type,
2355
                                                 data->named_arg);
2356
      data->partial = partial;
2357
 
2358
      /* The caller might already have allocated stack space for the
2359
         register parameters.  */
2360
      if (partial != 0 && all->reg_parm_stack_space == 0)
2361
        {
2362
          /* Part of this argument is passed in registers and part
2363
             is passed on the stack.  Ask the prologue code to extend
2364
             the stack part so that we can recreate the full value.
2365
 
2366
             PRETEND_BYTES is the size of the registers we need to store.
2367
             CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2368
             stack space that the prologue should allocate.
2369
 
2370
             Internally, gcc assumes that the argument pointer is aligned
2371
             to STACK_BOUNDARY bits.  This is used both for alignment
2372
             optimizations (see init_emit) and to locate arguments that are
2373
             aligned to more than PARM_BOUNDARY bits.  We must preserve this
2374
             invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2375
             a stack boundary.  */
2376
 
2377
          /* We assume at most one partial arg, and it must be the first
2378
             argument on the stack.  */
2379
          gcc_assert (!all->extra_pretend_bytes && !all->pretend_args_size);
2380
 
2381
          pretend_bytes = partial;
2382
          all->pretend_args_size = CEIL_ROUND (pretend_bytes, STACK_BYTES);
2383
 
2384
          /* We want to align relative to the actual stack pointer, so
2385
             don't include this in the stack size until later.  */
2386
          all->extra_pretend_bytes = all->pretend_args_size;
2387
        }
2388
    }
2389
 
2390
  locate_and_pad_parm (data->promoted_mode, data->passed_type, in_regs,
2391
                       entry_parm ? data->partial : 0, current_function_decl,
2392
                       &all->stack_args_size, &data->locate);
2393
 
2394
  /* Update parm_stack_boundary if this parameter is passed in the
2395
     stack.  */
2396
  if (!in_regs && crtl->parm_stack_boundary < data->locate.boundary)
2397
    crtl->parm_stack_boundary = data->locate.boundary;
2398
 
2399
  /* Adjust offsets to include the pretend args.  */
2400
  pretend_bytes = all->extra_pretend_bytes - pretend_bytes;
2401
  data->locate.slot_offset.constant += pretend_bytes;
2402
  data->locate.offset.constant += pretend_bytes;
2403
 
2404
  data->entry_parm = entry_parm;
2405
}
2406
 
2407
/* A subroutine of assign_parms.  If there is actually space on the stack
2408
   for this parm, count it in stack_args_size and return true.  */
2409
 
2410
static bool
2411
assign_parm_is_stack_parm (struct assign_parm_data_all *all,
2412
                           struct assign_parm_data_one *data)
2413
{
2414
  /* Trivially true if we've no incoming register.  */
2415
  if (data->entry_parm == NULL)
2416
    ;
2417
  /* Also true if we're partially in registers and partially not,
2418
     since we've arranged to drop the entire argument on the stack.  */
2419
  else if (data->partial != 0)
2420
    ;
2421
  /* Also true if the target says that it's passed in both registers
2422
     and on the stack.  */
2423
  else if (GET_CODE (data->entry_parm) == PARALLEL
2424
           && XEXP (XVECEXP (data->entry_parm, 0, 0), 0) == NULL_RTX)
2425
    ;
2426
  /* Also true if the target says that there's stack allocated for
2427
     all register parameters.  */
2428
  else if (all->reg_parm_stack_space > 0)
2429
    ;
2430
  /* Otherwise, no, this parameter has no ABI defined stack slot.  */
2431
  else
2432
    return false;
2433
 
2434
  all->stack_args_size.constant += data->locate.size.constant;
2435
  if (data->locate.size.var)
2436
    ADD_PARM_SIZE (all->stack_args_size, data->locate.size.var);
2437
 
2438
  return true;
2439
}
2440
 
2441
/* A subroutine of assign_parms.  Given that this parameter is allocated
2442
   stack space by the ABI, find it.  */
2443
 
2444
static void
2445
assign_parm_find_stack_rtl (tree parm, struct assign_parm_data_one *data)
2446
{
2447
  rtx offset_rtx, stack_parm;
2448
  unsigned int align, boundary;
2449
 
2450
  /* If we're passing this arg using a reg, make its stack home the
2451
     aligned stack slot.  */
2452
  if (data->entry_parm)
2453
    offset_rtx = ARGS_SIZE_RTX (data->locate.slot_offset);
2454
  else
2455
    offset_rtx = ARGS_SIZE_RTX (data->locate.offset);
2456
 
2457
  stack_parm = crtl->args.internal_arg_pointer;
2458
  if (offset_rtx != const0_rtx)
2459
    stack_parm = gen_rtx_PLUS (Pmode, stack_parm, offset_rtx);
2460
  stack_parm = gen_rtx_MEM (data->promoted_mode, stack_parm);
2461
 
2462
  if (!data->passed_pointer)
2463
    {
2464
      set_mem_attributes (stack_parm, parm, 1);
2465
      /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2466
         while promoted mode's size is needed.  */
2467
      if (data->promoted_mode != BLKmode
2468
          && data->promoted_mode != DECL_MODE (parm))
2469
        {
2470
          set_mem_size (stack_parm,
2471
                        GEN_INT (GET_MODE_SIZE (data->promoted_mode)));
2472
          if (MEM_EXPR (stack_parm) && MEM_OFFSET (stack_parm))
2473
            {
2474
              int offset = subreg_lowpart_offset (DECL_MODE (parm),
2475
                                                  data->promoted_mode);
2476
              if (offset)
2477
                set_mem_offset (stack_parm,
2478
                                plus_constant (MEM_OFFSET (stack_parm),
2479
                                               -offset));
2480
            }
2481
        }
2482
    }
2483
 
2484
  boundary = data->locate.boundary;
2485
  align = BITS_PER_UNIT;
2486
 
2487
  /* If we're padding upward, we know that the alignment of the slot
2488
     is FUNCTION_ARG_BOUNDARY.  If we're using slot_offset, we're
2489
     intentionally forcing upward padding.  Otherwise we have to come
2490
     up with a guess at the alignment based on OFFSET_RTX.  */
2491
  if (data->locate.where_pad != downward || data->entry_parm)
2492
    align = boundary;
2493
  else if (CONST_INT_P (offset_rtx))
2494
    {
2495
      align = INTVAL (offset_rtx) * BITS_PER_UNIT | boundary;
2496
      align = align & -align;
2497
    }
2498
  set_mem_align (stack_parm, align);
2499
 
2500
  if (data->entry_parm)
2501
    set_reg_attrs_for_parm (data->entry_parm, stack_parm);
2502
 
2503
  data->stack_parm = stack_parm;
2504
}
2505
 
2506
/* A subroutine of assign_parms.  Adjust DATA->ENTRY_RTL such that it's
2507
   always valid and contiguous.  */
2508
 
2509
static void
2510
assign_parm_adjust_entry_rtl (struct assign_parm_data_one *data)
2511
{
2512
  rtx entry_parm = data->entry_parm;
2513
  rtx stack_parm = data->stack_parm;
2514
 
2515
  /* If this parm was passed part in regs and part in memory, pretend it
2516
     arrived entirely in memory by pushing the register-part onto the stack.
2517
     In the special case of a DImode or DFmode that is split, we could put
2518
     it together in a pseudoreg directly, but for now that's not worth
2519
     bothering with.  */
2520
  if (data->partial != 0)
2521
    {
2522
      /* Handle calls that pass values in multiple non-contiguous
2523
         locations.  The Irix 6 ABI has examples of this.  */
2524
      if (GET_CODE (entry_parm) == PARALLEL)
2525
        emit_group_store (validize_mem (stack_parm), entry_parm,
2526
                          data->passed_type,
2527
                          int_size_in_bytes (data->passed_type));
2528
      else
2529
        {
2530
          gcc_assert (data->partial % UNITS_PER_WORD == 0);
2531
          move_block_from_reg (REGNO (entry_parm), validize_mem (stack_parm),
2532
                               data->partial / UNITS_PER_WORD);
2533
        }
2534
 
2535
      entry_parm = stack_parm;
2536
    }
2537
 
2538
  /* If we didn't decide this parm came in a register, by default it came
2539
     on the stack.  */
2540
  else if (entry_parm == NULL)
2541
    entry_parm = stack_parm;
2542
 
2543
  /* When an argument is passed in multiple locations, we can't make use
2544
     of this information, but we can save some copying if the whole argument
2545
     is passed in a single register.  */
2546
  else if (GET_CODE (entry_parm) == PARALLEL
2547
           && data->nominal_mode != BLKmode
2548
           && data->passed_mode != BLKmode)
2549
    {
2550
      size_t i, len = XVECLEN (entry_parm, 0);
2551
 
2552
      for (i = 0; i < len; i++)
2553
        if (XEXP (XVECEXP (entry_parm, 0, i), 0) != NULL_RTX
2554
            && REG_P (XEXP (XVECEXP (entry_parm, 0, i), 0))
2555
            && (GET_MODE (XEXP (XVECEXP (entry_parm, 0, i), 0))
2556
                == data->passed_mode)
2557
            && INTVAL (XEXP (XVECEXP (entry_parm, 0, i), 1)) == 0)
2558
          {
2559
            entry_parm = XEXP (XVECEXP (entry_parm, 0, i), 0);
2560
            break;
2561
          }
2562
    }
2563
 
2564
  data->entry_parm = entry_parm;
2565
}
2566
 
2567
/* A subroutine of assign_parms.  Reconstitute any values which were
2568
   passed in multiple registers and would fit in a single register.  */
2569
 
2570
static void
2571
assign_parm_remove_parallels (struct assign_parm_data_one *data)
2572
{
2573
  rtx entry_parm = data->entry_parm;
2574
 
2575
  /* Convert the PARALLEL to a REG of the same mode as the parallel.
2576
     This can be done with register operations rather than on the
2577
     stack, even if we will store the reconstituted parameter on the
2578
     stack later.  */
2579
  if (GET_CODE (entry_parm) == PARALLEL && GET_MODE (entry_parm) != BLKmode)
2580
    {
2581
      rtx parmreg = gen_reg_rtx (GET_MODE (entry_parm));
2582
      emit_group_store (parmreg, entry_parm, data->passed_type,
2583
                        GET_MODE_SIZE (GET_MODE (entry_parm)));
2584
      entry_parm = parmreg;
2585
    }
2586
 
2587
  data->entry_parm = entry_parm;
2588
}
2589
 
2590
/* A subroutine of assign_parms.  Adjust DATA->STACK_RTL such that it's
2591
   always valid and properly aligned.  */
2592
 
2593
static void
2594
assign_parm_adjust_stack_rtl (struct assign_parm_data_one *data)
2595
{
2596
  rtx stack_parm = data->stack_parm;
2597
 
2598
  /* If we can't trust the parm stack slot to be aligned enough for its
2599
     ultimate type, don't use that slot after entry.  We'll make another
2600
     stack slot, if we need one.  */
2601
  if (stack_parm
2602
      && ((STRICT_ALIGNMENT
2603
           && GET_MODE_ALIGNMENT (data->nominal_mode) > MEM_ALIGN (stack_parm))
2604
          || (data->nominal_type
2605
              && TYPE_ALIGN (data->nominal_type) > MEM_ALIGN (stack_parm)
2606
              && MEM_ALIGN (stack_parm) < PREFERRED_STACK_BOUNDARY)))
2607
    stack_parm = NULL;
2608
 
2609
  /* If parm was passed in memory, and we need to convert it on entry,
2610
     don't store it back in that same slot.  */
2611
  else if (data->entry_parm == stack_parm
2612
           && data->nominal_mode != BLKmode
2613
           && data->nominal_mode != data->passed_mode)
2614
    stack_parm = NULL;
2615
 
2616
  /* If stack protection is in effect for this function, don't leave any
2617
     pointers in their passed stack slots.  */
2618
  else if (crtl->stack_protect_guard
2619
           && (flag_stack_protect == 2
2620
               || data->passed_pointer
2621
               || POINTER_TYPE_P (data->nominal_type)))
2622
    stack_parm = NULL;
2623
 
2624
  data->stack_parm = stack_parm;
2625
}
2626
 
2627
/* A subroutine of assign_parms.  Return true if the current parameter
2628
   should be stored as a BLKmode in the current frame.  */
2629
 
2630
static bool
2631
assign_parm_setup_block_p (struct assign_parm_data_one *data)
2632
{
2633
  if (data->nominal_mode == BLKmode)
2634
    return true;
2635
  if (GET_MODE (data->entry_parm) == BLKmode)
2636
    return true;
2637
 
2638
#ifdef BLOCK_REG_PADDING
2639
  /* Only assign_parm_setup_block knows how to deal with register arguments
2640
     that are padded at the least significant end.  */
2641
  if (REG_P (data->entry_parm)
2642
      && GET_MODE_SIZE (data->promoted_mode) < UNITS_PER_WORD
2643
      && (BLOCK_REG_PADDING (data->passed_mode, data->passed_type, 1)
2644
          == (BYTES_BIG_ENDIAN ? upward : downward)))
2645
    return true;
2646
#endif
2647
 
2648
  return false;
2649
}
2650
 
2651
/* A subroutine of assign_parms.  Arrange for the parameter to be
2652
   present and valid in DATA->STACK_RTL.  */
2653
 
2654
static void
2655
assign_parm_setup_block (struct assign_parm_data_all *all,
2656
                         tree parm, struct assign_parm_data_one *data)
2657
{
2658
  rtx entry_parm = data->entry_parm;
2659
  rtx stack_parm = data->stack_parm;
2660
  HOST_WIDE_INT size;
2661
  HOST_WIDE_INT size_stored;
2662
 
2663
  if (GET_CODE (entry_parm) == PARALLEL)
2664
    entry_parm = emit_group_move_into_temps (entry_parm);
2665
 
2666
  size = int_size_in_bytes (data->passed_type);
2667
  size_stored = CEIL_ROUND (size, UNITS_PER_WORD);
2668
  if (stack_parm == 0)
2669
    {
2670
      DECL_ALIGN (parm) = MAX (DECL_ALIGN (parm), BITS_PER_WORD);
2671
      stack_parm = assign_stack_local (BLKmode, size_stored,
2672
                                       DECL_ALIGN (parm));
2673
      if (GET_MODE_SIZE (GET_MODE (entry_parm)) == size)
2674
        PUT_MODE (stack_parm, GET_MODE (entry_parm));
2675
      set_mem_attributes (stack_parm, parm, 1);
2676
    }
2677
 
2678
  /* If a BLKmode arrives in registers, copy it to a stack slot.  Handle
2679
     calls that pass values in multiple non-contiguous locations.  */
2680
  if (REG_P (entry_parm) || GET_CODE (entry_parm) == PARALLEL)
2681
    {
2682
      rtx mem;
2683
 
2684
      /* Note that we will be storing an integral number of words.
2685
         So we have to be careful to ensure that we allocate an
2686
         integral number of words.  We do this above when we call
2687
         assign_stack_local if space was not allocated in the argument
2688
         list.  If it was, this will not work if PARM_BOUNDARY is not
2689
         a multiple of BITS_PER_WORD.  It isn't clear how to fix this
2690
         if it becomes a problem.  Exception is when BLKmode arrives
2691
         with arguments not conforming to word_mode.  */
2692
 
2693
      if (data->stack_parm == 0)
2694
        ;
2695
      else if (GET_CODE (entry_parm) == PARALLEL)
2696
        ;
2697
      else
2698
        gcc_assert (!size || !(PARM_BOUNDARY % BITS_PER_WORD));
2699
 
2700
      mem = validize_mem (stack_parm);
2701
 
2702
      /* Handle values in multiple non-contiguous locations.  */
2703
      if (GET_CODE (entry_parm) == PARALLEL)
2704
        {
2705
          push_to_sequence2 (all->first_conversion_insn,
2706
                             all->last_conversion_insn);
2707
          emit_group_store (mem, entry_parm, data->passed_type, size);
2708
          all->first_conversion_insn = get_insns ();
2709
          all->last_conversion_insn = get_last_insn ();
2710
          end_sequence ();
2711
        }
2712
 
2713
      else if (size == 0)
2714
        ;
2715
 
2716
      /* If SIZE is that of a mode no bigger than a word, just use
2717
         that mode's store operation.  */
2718
      else if (size <= UNITS_PER_WORD)
2719
        {
2720
          enum machine_mode mode
2721
            = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2722
 
2723
          if (mode != BLKmode
2724
#ifdef BLOCK_REG_PADDING
2725
              && (size == UNITS_PER_WORD
2726
                  || (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2727
                      != (BYTES_BIG_ENDIAN ? upward : downward)))
2728
#endif
2729
              )
2730
            {
2731
              rtx reg;
2732
 
2733
              /* We are really truncating a word_mode value containing
2734
                 SIZE bytes into a value of mode MODE.  If such an
2735
                 operation requires no actual instructions, we can refer
2736
                 to the value directly in mode MODE, otherwise we must
2737
                 start with the register in word_mode and explicitly
2738
                 convert it.  */
2739
              if (TRULY_NOOP_TRUNCATION (size * BITS_PER_UNIT, BITS_PER_WORD))
2740
                reg = gen_rtx_REG (mode, REGNO (entry_parm));
2741
              else
2742
                {
2743
                  reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2744
                  reg = convert_to_mode (mode, copy_to_reg (reg), 1);
2745
                }
2746
              emit_move_insn (change_address (mem, mode, 0), reg);
2747
            }
2748
 
2749
          /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2750
             machine must be aligned to the left before storing
2751
             to memory.  Note that the previous test doesn't
2752
             handle all cases (e.g. SIZE == 3).  */
2753
          else if (size != UNITS_PER_WORD
2754
#ifdef BLOCK_REG_PADDING
2755
                   && (BLOCK_REG_PADDING (mode, data->passed_type, 1)
2756
                       == downward)
2757
#else
2758
                   && BYTES_BIG_ENDIAN
2759
#endif
2760
                   )
2761
            {
2762
              rtx tem, x;
2763
              int by = (UNITS_PER_WORD - size) * BITS_PER_UNIT;
2764
              rtx reg = gen_rtx_REG (word_mode, REGNO (entry_parm));
2765
 
2766
              x = expand_shift (LSHIFT_EXPR, word_mode, reg,
2767
                                build_int_cst (NULL_TREE, by),
2768
                                NULL_RTX, 1);
2769
              tem = change_address (mem, word_mode, 0);
2770
              emit_move_insn (tem, x);
2771
            }
2772
          else
2773
            move_block_from_reg (REGNO (entry_parm), mem,
2774
                                 size_stored / UNITS_PER_WORD);
2775
        }
2776
      else
2777
        move_block_from_reg (REGNO (entry_parm), mem,
2778
                             size_stored / UNITS_PER_WORD);
2779
    }
2780
  else if (data->stack_parm == 0)
2781
    {
2782
      push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2783
      emit_block_move (stack_parm, data->entry_parm, GEN_INT (size),
2784
                       BLOCK_OP_NORMAL);
2785
      all->first_conversion_insn = get_insns ();
2786
      all->last_conversion_insn = get_last_insn ();
2787
      end_sequence ();
2788
    }
2789
 
2790
  data->stack_parm = stack_parm;
2791
  SET_DECL_RTL (parm, stack_parm);
2792
}
2793
 
2794
/* A subroutine of assign_parms.  Allocate a pseudo to hold the current
2795
   parameter.  Get it there.  Perform all ABI specified conversions.  */
2796
 
2797
static void
2798
assign_parm_setup_reg (struct assign_parm_data_all *all, tree parm,
2799
                       struct assign_parm_data_one *data)
2800
{
2801
  rtx parmreg;
2802
  enum machine_mode promoted_nominal_mode;
2803
  int unsignedp = TYPE_UNSIGNED (TREE_TYPE (parm));
2804
  bool did_conversion = false;
2805
 
2806
  /* Store the parm in a pseudoregister during the function, but we may
2807
     need to do it in a wider mode.  Using 2 here makes the result
2808
     consistent with promote_decl_mode and thus expand_expr_real_1.  */
2809
  promoted_nominal_mode
2810
    = promote_function_mode (data->nominal_type, data->nominal_mode, &unsignedp,
2811
                             TREE_TYPE (current_function_decl), 2);
2812
 
2813
  parmreg = gen_reg_rtx (promoted_nominal_mode);
2814
 
2815
  if (!DECL_ARTIFICIAL (parm))
2816
    mark_user_reg (parmreg);
2817
 
2818
  /* If this was an item that we received a pointer to,
2819
     set DECL_RTL appropriately.  */
2820
  if (data->passed_pointer)
2821
    {
2822
      rtx x = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data->passed_type)), parmreg);
2823
      set_mem_attributes (x, parm, 1);
2824
      SET_DECL_RTL (parm, x);
2825
    }
2826
  else
2827
    SET_DECL_RTL (parm, parmreg);
2828
 
2829
  assign_parm_remove_parallels (data);
2830
 
2831
  /* Copy the value into the register, thus bridging between
2832
     assign_parm_find_data_types and expand_expr_real_1.  */
2833
  if (data->nominal_mode != data->passed_mode
2834
      || promoted_nominal_mode != data->promoted_mode)
2835
    {
2836
      int save_tree_used;
2837
 
2838
      /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2839
         mode, by the caller.  We now have to convert it to
2840
         NOMINAL_MODE, if different.  However, PARMREG may be in
2841
         a different mode than NOMINAL_MODE if it is being stored
2842
         promoted.
2843
 
2844
         If ENTRY_PARM is a hard register, it might be in a register
2845
         not valid for operating in its mode (e.g., an odd-numbered
2846
         register for a DFmode).  In that case, moves are the only
2847
         thing valid, so we can't do a convert from there.  This
2848
         occurs when the calling sequence allow such misaligned
2849
         usages.
2850
 
2851
         In addition, the conversion may involve a call, which could
2852
         clobber parameters which haven't been copied to pseudo
2853
         registers yet.  Therefore, we must first copy the parm to
2854
         a pseudo reg here, and save the conversion until after all
2855
         parameters have been moved.  */
2856
 
2857
      rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
2858
 
2859
      emit_move_insn (tempreg, validize_mem (data->entry_parm));
2860
 
2861
      push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
2862
      tempreg = convert_to_mode (data->nominal_mode, tempreg, unsignedp);
2863
 
2864
      if (GET_CODE (tempreg) == SUBREG
2865
          && GET_MODE (tempreg) == data->nominal_mode
2866
          && REG_P (SUBREG_REG (tempreg))
2867
          && data->nominal_mode == data->passed_mode
2868
          && GET_MODE (SUBREG_REG (tempreg)) == GET_MODE (data->entry_parm)
2869
          && GET_MODE_SIZE (GET_MODE (tempreg))
2870
             < GET_MODE_SIZE (GET_MODE (data->entry_parm)))
2871
        {
2872
          /* The argument is already sign/zero extended, so note it
2873
             into the subreg.  */
2874
          SUBREG_PROMOTED_VAR_P (tempreg) = 1;
2875
          SUBREG_PROMOTED_UNSIGNED_SET (tempreg, unsignedp);
2876
        }
2877
 
2878
      /* TREE_USED gets set erroneously during expand_assignment.  */
2879
      save_tree_used = TREE_USED (parm);
2880
      expand_assignment (parm, make_tree (data->nominal_type, tempreg), false);
2881
      TREE_USED (parm) = save_tree_used;
2882
      all->first_conversion_insn = get_insns ();
2883
      all->last_conversion_insn = get_last_insn ();
2884
      end_sequence ();
2885
 
2886
      did_conversion = true;
2887
    }
2888
  else
2889
    emit_move_insn (parmreg, validize_mem (data->entry_parm));
2890
 
2891
  /* If we were passed a pointer but the actual value can safely live
2892
     in a register, put it in one.  */
2893
  if (data->passed_pointer
2894
      && TYPE_MODE (TREE_TYPE (parm)) != BLKmode
2895
      /* If by-reference argument was promoted, demote it.  */
2896
      && (TYPE_MODE (TREE_TYPE (parm)) != GET_MODE (DECL_RTL (parm))
2897
          || use_register_for_decl (parm)))
2898
    {
2899
      /* We can't use nominal_mode, because it will have been set to
2900
         Pmode above.  We must use the actual mode of the parm.  */
2901
      parmreg = gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm)));
2902
      mark_user_reg (parmreg);
2903
 
2904
      if (GET_MODE (parmreg) != GET_MODE (DECL_RTL (parm)))
2905
        {
2906
          rtx tempreg = gen_reg_rtx (GET_MODE (DECL_RTL (parm)));
2907
          int unsigned_p = TYPE_UNSIGNED (TREE_TYPE (parm));
2908
 
2909
          push_to_sequence2 (all->first_conversion_insn,
2910
                             all->last_conversion_insn);
2911
          emit_move_insn (tempreg, DECL_RTL (parm));
2912
          tempreg = convert_to_mode (GET_MODE (parmreg), tempreg, unsigned_p);
2913
          emit_move_insn (parmreg, tempreg);
2914
          all->first_conversion_insn = get_insns ();
2915
          all->last_conversion_insn = get_last_insn ();
2916
          end_sequence ();
2917
 
2918
          did_conversion = true;
2919
        }
2920
      else
2921
        emit_move_insn (parmreg, DECL_RTL (parm));
2922
 
2923
      SET_DECL_RTL (parm, parmreg);
2924
 
2925
      /* STACK_PARM is the pointer, not the parm, and PARMREG is
2926
         now the parm.  */
2927
      data->stack_parm = NULL;
2928
    }
2929
 
2930
  /* Mark the register as eliminable if we did no conversion and it was
2931
     copied from memory at a fixed offset, and the arg pointer was not
2932
     copied to a pseudo-reg.  If the arg pointer is a pseudo reg or the
2933
     offset formed an invalid address, such memory-equivalences as we
2934
     make here would screw up life analysis for it.  */
2935
  if (data->nominal_mode == data->passed_mode
2936
      && !did_conversion
2937
      && data->stack_parm != 0
2938
      && MEM_P (data->stack_parm)
2939
      && data->locate.offset.var == 0
2940
      && reg_mentioned_p (virtual_incoming_args_rtx,
2941
                          XEXP (data->stack_parm, 0)))
2942
    {
2943
      rtx linsn = get_last_insn ();
2944
      rtx sinsn, set;
2945
 
2946
      /* Mark complex types separately.  */
2947
      if (GET_CODE (parmreg) == CONCAT)
2948
        {
2949
          enum machine_mode submode
2950
            = GET_MODE_INNER (GET_MODE (parmreg));
2951
          int regnor = REGNO (XEXP (parmreg, 0));
2952
          int regnoi = REGNO (XEXP (parmreg, 1));
2953
          rtx stackr = adjust_address_nv (data->stack_parm, submode, 0);
2954
          rtx stacki = adjust_address_nv (data->stack_parm, submode,
2955
                                          GET_MODE_SIZE (submode));
2956
 
2957
          /* Scan backwards for the set of the real and
2958
             imaginary parts.  */
2959
          for (sinsn = linsn; sinsn != 0;
2960
               sinsn = prev_nonnote_insn (sinsn))
2961
            {
2962
              set = single_set (sinsn);
2963
              if (set == 0)
2964
                continue;
2965
 
2966
              if (SET_DEST (set) == regno_reg_rtx [regnoi])
2967
                set_unique_reg_note (sinsn, REG_EQUIV, stacki);
2968
              else if (SET_DEST (set) == regno_reg_rtx [regnor])
2969
                set_unique_reg_note (sinsn, REG_EQUIV, stackr);
2970
            }
2971
        }
2972
      else if ((set = single_set (linsn)) != 0
2973
               && SET_DEST (set) == parmreg)
2974
        set_unique_reg_note (linsn, REG_EQUIV, data->stack_parm);
2975
    }
2976
 
2977
  /* For pointer data type, suggest pointer register.  */
2978
  if (POINTER_TYPE_P (TREE_TYPE (parm)))
2979
    mark_reg_pointer (parmreg,
2980
                      TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
2981
}
2982
 
2983
/* A subroutine of assign_parms.  Allocate stack space to hold the current
2984
   parameter.  Get it there.  Perform all ABI specified conversions.  */
2985
 
2986
static void
2987
assign_parm_setup_stack (struct assign_parm_data_all *all, tree parm,
2988
                         struct assign_parm_data_one *data)
2989
{
2990
  /* Value must be stored in the stack slot STACK_PARM during function
2991
     execution.  */
2992
  bool to_conversion = false;
2993
 
2994
  assign_parm_remove_parallels (data);
2995
 
2996
  if (data->promoted_mode != data->nominal_mode)
2997
    {
2998
      /* Conversion is required.  */
2999
      rtx tempreg = gen_reg_rtx (GET_MODE (data->entry_parm));
3000
 
3001
      emit_move_insn (tempreg, validize_mem (data->entry_parm));
3002
 
3003
      push_to_sequence2 (all->first_conversion_insn, all->last_conversion_insn);
3004
      to_conversion = true;
3005
 
3006
      data->entry_parm = convert_to_mode (data->nominal_mode, tempreg,
3007
                                          TYPE_UNSIGNED (TREE_TYPE (parm)));
3008
 
3009
      if (data->stack_parm)
3010
        {
3011
          int offset = subreg_lowpart_offset (data->nominal_mode,
3012
                                              GET_MODE (data->stack_parm));
3013
          /* ??? This may need a big-endian conversion on sparc64.  */
3014
          data->stack_parm
3015
            = adjust_address (data->stack_parm, data->nominal_mode, 0);
3016
          if (offset && MEM_OFFSET (data->stack_parm))
3017
            set_mem_offset (data->stack_parm,
3018
                            plus_constant (MEM_OFFSET (data->stack_parm),
3019
                                           offset));
3020
        }
3021
    }
3022
 
3023
  if (data->entry_parm != data->stack_parm)
3024
    {
3025
      rtx src, dest;
3026
 
3027
      if (data->stack_parm == 0)
3028
        {
3029
          int align = STACK_SLOT_ALIGNMENT (data->passed_type,
3030
                                            GET_MODE (data->entry_parm),
3031
                                            TYPE_ALIGN (data->passed_type));
3032
          data->stack_parm
3033
            = assign_stack_local (GET_MODE (data->entry_parm),
3034
                                  GET_MODE_SIZE (GET_MODE (data->entry_parm)),
3035
                                  align);
3036
          set_mem_attributes (data->stack_parm, parm, 1);
3037
        }
3038
 
3039
      dest = validize_mem (data->stack_parm);
3040
      src = validize_mem (data->entry_parm);
3041
 
3042
      if (MEM_P (src))
3043
        {
3044
          /* Use a block move to handle potentially misaligned entry_parm.  */
3045
          if (!to_conversion)
3046
            push_to_sequence2 (all->first_conversion_insn,
3047
                               all->last_conversion_insn);
3048
          to_conversion = true;
3049
 
3050
          emit_block_move (dest, src,
3051
                           GEN_INT (int_size_in_bytes (data->passed_type)),
3052
                           BLOCK_OP_NORMAL);
3053
        }
3054
      else
3055
        emit_move_insn (dest, src);
3056
    }
3057
 
3058
  if (to_conversion)
3059
    {
3060
      all->first_conversion_insn = get_insns ();
3061
      all->last_conversion_insn = get_last_insn ();
3062
      end_sequence ();
3063
    }
3064
 
3065
  SET_DECL_RTL (parm, data->stack_parm);
3066
}
3067
 
3068
/* A subroutine of assign_parms.  If the ABI splits complex arguments, then
3069
   undo the frobbing that we did in assign_parms_augmented_arg_list.  */
3070
 
3071
static void
3072
assign_parms_unsplit_complex (struct assign_parm_data_all *all,
3073
                              VEC(tree, heap) *fnargs)
3074
{
3075
  tree parm;
3076
  tree orig_fnargs = all->orig_fnargs;
3077
  unsigned i = 0;
3078
 
3079
  for (parm = orig_fnargs; parm; parm = TREE_CHAIN (parm), ++i)
3080
    {
3081
      if (TREE_CODE (TREE_TYPE (parm)) == COMPLEX_TYPE
3082
          && targetm.calls.split_complex_arg (TREE_TYPE (parm)))
3083
        {
3084
          rtx tmp, real, imag;
3085
          enum machine_mode inner = GET_MODE_INNER (DECL_MODE (parm));
3086
 
3087
          real = DECL_RTL (VEC_index (tree, fnargs, i));
3088
          imag = DECL_RTL (VEC_index (tree, fnargs, i + 1));
3089
          if (inner != GET_MODE (real))
3090
            {
3091
              real = gen_lowpart_SUBREG (inner, real);
3092
              imag = gen_lowpart_SUBREG (inner, imag);
3093
            }
3094
 
3095
          if (TREE_ADDRESSABLE (parm))
3096
            {
3097
              rtx rmem, imem;
3098
              HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (parm));
3099
              int align = STACK_SLOT_ALIGNMENT (TREE_TYPE (parm),
3100
                                                DECL_MODE (parm),
3101
                                                TYPE_ALIGN (TREE_TYPE (parm)));
3102
 
3103
              /* split_complex_arg put the real and imag parts in
3104
                 pseudos.  Move them to memory.  */
3105
              tmp = assign_stack_local (DECL_MODE (parm), size, align);
3106
              set_mem_attributes (tmp, parm, 1);
3107
              rmem = adjust_address_nv (tmp, inner, 0);
3108
              imem = adjust_address_nv (tmp, inner, GET_MODE_SIZE (inner));
3109
              push_to_sequence2 (all->first_conversion_insn,
3110
                                 all->last_conversion_insn);
3111
              emit_move_insn (rmem, real);
3112
              emit_move_insn (imem, imag);
3113
              all->first_conversion_insn = get_insns ();
3114
              all->last_conversion_insn = get_last_insn ();
3115
              end_sequence ();
3116
            }
3117
          else
3118
            tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3119
          SET_DECL_RTL (parm, tmp);
3120
 
3121
          real = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i));
3122
          imag = DECL_INCOMING_RTL (VEC_index (tree, fnargs, i + 1));
3123
          if (inner != GET_MODE (real))
3124
            {
3125
              real = gen_lowpart_SUBREG (inner, real);
3126
              imag = gen_lowpart_SUBREG (inner, imag);
3127
            }
3128
          tmp = gen_rtx_CONCAT (DECL_MODE (parm), real, imag);
3129
          set_decl_incoming_rtl (parm, tmp, false);
3130
          i++;
3131
        }
3132
    }
3133
}
3134
 
3135
/* Assign RTL expressions to the function's parameters.  This may involve
3136
   copying them into registers and using those registers as the DECL_RTL.  */
3137
 
3138
static void
3139
assign_parms (tree fndecl)
3140
{
3141
  struct assign_parm_data_all all;
3142
  tree parm;
3143
  VEC(tree, heap) *fnargs;
3144
  unsigned i;
3145
 
3146
  crtl->args.internal_arg_pointer
3147
    = targetm.calls.internal_arg_pointer ();
3148
 
3149
  assign_parms_initialize_all (&all);
3150
  fnargs = assign_parms_augmented_arg_list (&all);
3151
 
3152
  for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3153
    {
3154
      struct assign_parm_data_one data;
3155
 
3156
      /* Extract the type of PARM; adjust it according to ABI.  */
3157
      assign_parm_find_data_types (&all, parm, &data);
3158
 
3159
      /* Early out for errors and void parameters.  */
3160
      if (data.passed_mode == VOIDmode)
3161
        {
3162
          SET_DECL_RTL (parm, const0_rtx);
3163
          DECL_INCOMING_RTL (parm) = DECL_RTL (parm);
3164
          continue;
3165
        }
3166
 
3167
      /* Estimate stack alignment from parameter alignment.  */
3168
      if (SUPPORTS_STACK_ALIGNMENT)
3169
        {
3170
          unsigned int align = FUNCTION_ARG_BOUNDARY (data.promoted_mode,
3171
                                                      data.passed_type);
3172
          align = MINIMUM_ALIGNMENT (data.passed_type, data.promoted_mode,
3173
                                     align);
3174
          if (TYPE_ALIGN (data.nominal_type) > align)
3175
            align = MINIMUM_ALIGNMENT (data.nominal_type,
3176
                                       TYPE_MODE (data.nominal_type),
3177
                                       TYPE_ALIGN (data.nominal_type));
3178
          if (crtl->stack_alignment_estimated < align)
3179
            {
3180
              gcc_assert (!crtl->stack_realign_processed);
3181
              crtl->stack_alignment_estimated = align;
3182
            }
3183
        }
3184
 
3185
      if (cfun->stdarg && !TREE_CHAIN (parm))
3186
        assign_parms_setup_varargs (&all, &data, false);
3187
 
3188
      /* Find out where the parameter arrives in this function.  */
3189
      assign_parm_find_entry_rtl (&all, &data);
3190
 
3191
      /* Find out where stack space for this parameter might be.  */
3192
      if (assign_parm_is_stack_parm (&all, &data))
3193
        {
3194
          assign_parm_find_stack_rtl (parm, &data);
3195
          assign_parm_adjust_entry_rtl (&data);
3196
        }
3197
 
3198
      /* Record permanently how this parm was passed.  */
3199
      set_decl_incoming_rtl (parm, data.entry_parm, data.passed_pointer);
3200
 
3201
      /* Update info on where next arg arrives in registers.  */
3202
      FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3203
                            data.passed_type, data.named_arg);
3204
 
3205
      assign_parm_adjust_stack_rtl (&data);
3206
 
3207
      if (assign_parm_setup_block_p (&data))
3208
        assign_parm_setup_block (&all, parm, &data);
3209
      else if (data.passed_pointer || use_register_for_decl (parm))
3210
        assign_parm_setup_reg (&all, parm, &data);
3211
      else
3212
        assign_parm_setup_stack (&all, parm, &data);
3213
    }
3214
 
3215
  if (targetm.calls.split_complex_arg)
3216
    assign_parms_unsplit_complex (&all, fnargs);
3217
 
3218
  VEC_free (tree, heap, fnargs);
3219
 
3220
  /* Output all parameter conversion instructions (possibly including calls)
3221
     now that all parameters have been copied out of hard registers.  */
3222
  emit_insn (all.first_conversion_insn);
3223
 
3224
  /* Estimate reload stack alignment from scalar return mode.  */
3225
  if (SUPPORTS_STACK_ALIGNMENT)
3226
    {
3227
      if (DECL_RESULT (fndecl))
3228
        {
3229
          tree type = TREE_TYPE (DECL_RESULT (fndecl));
3230
          enum machine_mode mode = TYPE_MODE (type);
3231
 
3232
          if (mode != BLKmode
3233
              && mode != VOIDmode
3234
              && !AGGREGATE_TYPE_P (type))
3235
            {
3236
              unsigned int align = GET_MODE_ALIGNMENT (mode);
3237
              if (crtl->stack_alignment_estimated < align)
3238
                {
3239
                  gcc_assert (!crtl->stack_realign_processed);
3240
                  crtl->stack_alignment_estimated = align;
3241
                }
3242
            }
3243
        }
3244
    }
3245
 
3246
  /* If we are receiving a struct value address as the first argument, set up
3247
     the RTL for the function result. As this might require code to convert
3248
     the transmitted address to Pmode, we do this here to ensure that possible
3249
     preliminary conversions of the address have been emitted already.  */
3250
  if (all.function_result_decl)
3251
    {
3252
      tree result = DECL_RESULT (current_function_decl);
3253
      rtx addr = DECL_RTL (all.function_result_decl);
3254
      rtx x;
3255
 
3256
      if (DECL_BY_REFERENCE (result))
3257
        x = addr;
3258
      else
3259
        {
3260
          addr = convert_memory_address (Pmode, addr);
3261
          x = gen_rtx_MEM (DECL_MODE (result), addr);
3262
          set_mem_attributes (x, result, 1);
3263
        }
3264
      SET_DECL_RTL (result, x);
3265
    }
3266
 
3267
  /* We have aligned all the args, so add space for the pretend args.  */
3268
  crtl->args.pretend_args_size = all.pretend_args_size;
3269
  all.stack_args_size.constant += all.extra_pretend_bytes;
3270
  crtl->args.size = all.stack_args_size.constant;
3271
 
3272
  /* Adjust function incoming argument size for alignment and
3273
     minimum length.  */
3274
 
3275
#ifdef REG_PARM_STACK_SPACE
3276
  crtl->args.size = MAX (crtl->args.size,
3277
                                    REG_PARM_STACK_SPACE (fndecl));
3278
#endif
3279
 
3280
  crtl->args.size = CEIL_ROUND (crtl->args.size,
3281
                                           PARM_BOUNDARY / BITS_PER_UNIT);
3282
 
3283
#ifdef ARGS_GROW_DOWNWARD
3284
  crtl->args.arg_offset_rtx
3285
    = (all.stack_args_size.var == 0 ? GEN_INT (-all.stack_args_size.constant)
3286
       : expand_expr (size_diffop (all.stack_args_size.var,
3287
                                   size_int (-all.stack_args_size.constant)),
3288
                      NULL_RTX, VOIDmode, EXPAND_NORMAL));
3289
#else
3290
  crtl->args.arg_offset_rtx = ARGS_SIZE_RTX (all.stack_args_size);
3291
#endif
3292
 
3293
  /* See how many bytes, if any, of its args a function should try to pop
3294
     on return.  */
3295
 
3296
  crtl->args.pops_args = RETURN_POPS_ARGS (fndecl, TREE_TYPE (fndecl),
3297
                                                 crtl->args.size);
3298
 
3299
  /* For stdarg.h function, save info about
3300
     regs and stack space used by the named args.  */
3301
 
3302
  crtl->args.info = all.args_so_far;
3303
 
3304
  /* Set the rtx used for the function return value.  Put this in its
3305
     own variable so any optimizers that need this information don't have
3306
     to include tree.h.  Do this here so it gets done when an inlined
3307
     function gets output.  */
3308
 
3309
  crtl->return_rtx
3310
    = (DECL_RTL_SET_P (DECL_RESULT (fndecl))
3311
       ? DECL_RTL (DECL_RESULT (fndecl)) : NULL_RTX);
3312
 
3313
  /* If scalar return value was computed in a pseudo-reg, or was a named
3314
     return value that got dumped to the stack, copy that to the hard
3315
     return register.  */
3316
  if (DECL_RTL_SET_P (DECL_RESULT (fndecl)))
3317
    {
3318
      tree decl_result = DECL_RESULT (fndecl);
3319
      rtx decl_rtl = DECL_RTL (decl_result);
3320
 
3321
      if (REG_P (decl_rtl)
3322
          ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
3323
          : DECL_REGISTER (decl_result))
3324
        {
3325
          rtx real_decl_rtl;
3326
 
3327
          real_decl_rtl = targetm.calls.function_value (TREE_TYPE (decl_result),
3328
                                                        fndecl, true);
3329
          REG_FUNCTION_VALUE_P (real_decl_rtl) = 1;
3330
          /* The delay slot scheduler assumes that crtl->return_rtx
3331
             holds the hard register containing the return value, not a
3332
             temporary pseudo.  */
3333
          crtl->return_rtx = real_decl_rtl;
3334
        }
3335
    }
3336
}
3337
 
3338
/* A subroutine of gimplify_parameters, invoked via walk_tree.
3339
   For all seen types, gimplify their sizes.  */
3340
 
3341
static tree
3342
gimplify_parm_type (tree *tp, int *walk_subtrees, void *data)
3343
{
3344
  tree t = *tp;
3345
 
3346
  *walk_subtrees = 0;
3347
  if (TYPE_P (t))
3348
    {
3349
      if (POINTER_TYPE_P (t))
3350
        *walk_subtrees = 1;
3351
      else if (TYPE_SIZE (t) && !TREE_CONSTANT (TYPE_SIZE (t))
3352
               && !TYPE_SIZES_GIMPLIFIED (t))
3353
        {
3354
          gimplify_type_sizes (t, (gimple_seq *) data);
3355
          *walk_subtrees = 1;
3356
        }
3357
    }
3358
 
3359
  return NULL;
3360
}
3361
 
3362
/* Gimplify the parameter list for current_function_decl.  This involves
3363
   evaluating SAVE_EXPRs of variable sized parameters and generating code
3364
   to implement callee-copies reference parameters.  Returns a sequence of
3365
   statements to add to the beginning of the function.  */
3366
 
3367
gimple_seq
3368
gimplify_parameters (void)
3369
{
3370
  struct assign_parm_data_all all;
3371
  tree parm;
3372
  gimple_seq stmts = NULL;
3373
  VEC(tree, heap) *fnargs;
3374
  unsigned i;
3375
 
3376
  assign_parms_initialize_all (&all);
3377
  fnargs = assign_parms_augmented_arg_list (&all);
3378
 
3379
  for (i = 0; VEC_iterate (tree, fnargs, i, parm); ++i)
3380
    {
3381
      struct assign_parm_data_one data;
3382
 
3383
      /* Extract the type of PARM; adjust it according to ABI.  */
3384
      assign_parm_find_data_types (&all, parm, &data);
3385
 
3386
      /* Early out for errors and void parameters.  */
3387
      if (data.passed_mode == VOIDmode || DECL_SIZE (parm) == NULL)
3388
        continue;
3389
 
3390
      /* Update info on where next arg arrives in registers.  */
3391
      FUNCTION_ARG_ADVANCE (all.args_so_far, data.promoted_mode,
3392
                            data.passed_type, data.named_arg);
3393
 
3394
      /* ??? Once upon a time variable_size stuffed parameter list
3395
         SAVE_EXPRs (amongst others) onto a pending sizes list.  This
3396
         turned out to be less than manageable in the gimple world.
3397
         Now we have to hunt them down ourselves.  */
3398
      walk_tree_without_duplicates (&data.passed_type,
3399
                                    gimplify_parm_type, &stmts);
3400
 
3401
      if (TREE_CODE (DECL_SIZE_UNIT (parm)) != INTEGER_CST)
3402
        {
3403
          gimplify_one_sizepos (&DECL_SIZE (parm), &stmts);
3404
          gimplify_one_sizepos (&DECL_SIZE_UNIT (parm), &stmts);
3405
        }
3406
 
3407
      if (data.passed_pointer)
3408
        {
3409
          tree type = TREE_TYPE (data.passed_type);
3410
          if (reference_callee_copied (&all.args_so_far, TYPE_MODE (type),
3411
                                       type, data.named_arg))
3412
            {
3413
              tree local, t;
3414
 
3415
              /* For constant-sized objects, this is trivial; for
3416
                 variable-sized objects, we have to play games.  */
3417
              if (TREE_CODE (DECL_SIZE_UNIT (parm)) == INTEGER_CST
3418
                  && !(flag_stack_check == GENERIC_STACK_CHECK
3419
                       && compare_tree_int (DECL_SIZE_UNIT (parm),
3420
                                            STACK_CHECK_MAX_VAR_SIZE) > 0))
3421
                {
3422
                  local = create_tmp_var (type, get_name (parm));
3423
                  DECL_IGNORED_P (local) = 0;
3424
                  /* If PARM was addressable, move that flag over
3425
                     to the local copy, as its address will be taken,
3426 378 julius
                     not the PARMs.  Keep the parms address taken
3427
                     as we'll query that flag during gimplification.  */
3428 280 jeremybenn
                  if (TREE_ADDRESSABLE (parm))
3429 378 julius
                    TREE_ADDRESSABLE (local) = 1;
3430 280 jeremybenn
                }
3431
              else
3432
                {
3433
                  tree ptr_type, addr;
3434
 
3435
                  ptr_type = build_pointer_type (type);
3436
                  addr = create_tmp_var (ptr_type, get_name (parm));
3437
                  DECL_IGNORED_P (addr) = 0;
3438
                  local = build_fold_indirect_ref (addr);
3439
 
3440
                  t = built_in_decls[BUILT_IN_ALLOCA];
3441
                  t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3442
                  t = fold_convert (ptr_type, t);
3443
                  t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3444
                  gimplify_and_add (t, &stmts);
3445
                }
3446
 
3447
              gimplify_assign (local, parm, &stmts);
3448
 
3449
              SET_DECL_VALUE_EXPR (parm, local);
3450
              DECL_HAS_VALUE_EXPR_P (parm) = 1;
3451
            }
3452
        }
3453
    }
3454
 
3455
  VEC_free (tree, heap, fnargs);
3456
 
3457
  return stmts;
3458
}
3459
 
3460
/* Compute the size and offset from the start of the stacked arguments for a
3461
   parm passed in mode PASSED_MODE and with type TYPE.
3462
 
3463
   INITIAL_OFFSET_PTR points to the current offset into the stacked
3464
   arguments.
3465
 
3466
   The starting offset and size for this parm are returned in
3467
   LOCATE->OFFSET and LOCATE->SIZE, respectively.  When IN_REGS is
3468
   nonzero, the offset is that of stack slot, which is returned in
3469
   LOCATE->SLOT_OFFSET.  LOCATE->ALIGNMENT_PAD is the amount of
3470
   padding required from the initial offset ptr to the stack slot.
3471
 
3472
   IN_REGS is nonzero if the argument will be passed in registers.  It will
3473
   never be set if REG_PARM_STACK_SPACE is not defined.
3474
 
3475
   FNDECL is the function in which the argument was defined.
3476
 
3477
   There are two types of rounding that are done.  The first, controlled by
3478
   FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3479
   list to be aligned to the specific boundary (in bits).  This rounding
3480
   affects the initial and starting offsets, but not the argument size.
3481
 
3482
   The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3483
   optionally rounds the size of the parm to PARM_BOUNDARY.  The
3484
   initial offset is not affected by this rounding, while the size always
3485
   is and the starting offset may be.  */
3486
 
3487
/*  LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3488
    INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3489
    callers pass in the total size of args so far as
3490
    INITIAL_OFFSET_PTR.  LOCATE->SIZE is always positive.  */
3491
 
3492
void
3493
locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3494
                     int partial, tree fndecl ATTRIBUTE_UNUSED,
3495
                     struct args_size *initial_offset_ptr,
3496
                     struct locate_and_pad_arg_data *locate)
3497
{
3498
  tree sizetree;
3499
  enum direction where_pad;
3500
  unsigned int boundary;
3501
  int reg_parm_stack_space = 0;
3502
  int part_size_in_regs;
3503
 
3504
#ifdef REG_PARM_STACK_SPACE
3505
  reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3506
 
3507
  /* If we have found a stack parm before we reach the end of the
3508
     area reserved for registers, skip that area.  */
3509
  if (! in_regs)
3510
    {
3511
      if (reg_parm_stack_space > 0)
3512
        {
3513
          if (initial_offset_ptr->var)
3514
            {
3515
              initial_offset_ptr->var
3516
                = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3517
                              ssize_int (reg_parm_stack_space));
3518
              initial_offset_ptr->constant = 0;
3519
            }
3520
          else if (initial_offset_ptr->constant < reg_parm_stack_space)
3521
            initial_offset_ptr->constant = reg_parm_stack_space;
3522
        }
3523
    }
3524
#endif /* REG_PARM_STACK_SPACE */
3525
 
3526
  part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3527
 
3528
  sizetree
3529
    = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3530
  where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3531
  boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3532
  locate->where_pad = where_pad;
3533
 
3534
  /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT.  */
3535
  if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3536
    boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3537
 
3538
  locate->boundary = boundary;
3539
 
3540
  if (SUPPORTS_STACK_ALIGNMENT)
3541
    {
3542
      /* stack_alignment_estimated can't change after stack has been
3543
         realigned.  */
3544
      if (crtl->stack_alignment_estimated < boundary)
3545
        {
3546
          if (!crtl->stack_realign_processed)
3547
            crtl->stack_alignment_estimated = boundary;
3548
          else
3549
            {
3550
              /* If stack is realigned and stack alignment value
3551
                 hasn't been finalized, it is OK not to increase
3552
                 stack_alignment_estimated.  The bigger alignment
3553
                 requirement is recorded in stack_alignment_needed
3554
                 below.  */
3555
              gcc_assert (!crtl->stack_realign_finalized
3556
                          && crtl->stack_realign_needed);
3557
            }
3558
        }
3559
    }
3560
 
3561
  /* Remember if the outgoing parameter requires extra alignment on the
3562
     calling function side.  */
3563
  if (crtl->stack_alignment_needed < boundary)
3564
    crtl->stack_alignment_needed = boundary;
3565
  if (crtl->preferred_stack_boundary < boundary)
3566
    crtl->preferred_stack_boundary = boundary;
3567
 
3568
#ifdef ARGS_GROW_DOWNWARD
3569
  locate->slot_offset.constant = -initial_offset_ptr->constant;
3570
  if (initial_offset_ptr->var)
3571
    locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3572
                                          initial_offset_ptr->var);
3573
 
3574
  {
3575
    tree s2 = sizetree;
3576
    if (where_pad != none
3577
        && (!host_integerp (sizetree, 1)
3578
            || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3579
      s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3580
    SUB_PARM_SIZE (locate->slot_offset, s2);
3581
  }
3582
 
3583
  locate->slot_offset.constant += part_size_in_regs;
3584
 
3585
  if (!in_regs
3586
#ifdef REG_PARM_STACK_SPACE
3587
      || REG_PARM_STACK_SPACE (fndecl) > 0
3588
#endif
3589
     )
3590
    pad_to_arg_alignment (&locate->slot_offset, boundary,
3591
                          &locate->alignment_pad);
3592
 
3593
  locate->size.constant = (-initial_offset_ptr->constant
3594
                           - locate->slot_offset.constant);
3595
  if (initial_offset_ptr->var)
3596
    locate->size.var = size_binop (MINUS_EXPR,
3597
                                   size_binop (MINUS_EXPR,
3598
                                               ssize_int (0),
3599
                                               initial_offset_ptr->var),
3600
                                   locate->slot_offset.var);
3601
 
3602
  /* Pad_below needs the pre-rounded size to know how much to pad
3603
     below.  */
3604
  locate->offset = locate->slot_offset;
3605
  if (where_pad == downward)
3606
    pad_below (&locate->offset, passed_mode, sizetree);
3607
 
3608
#else /* !ARGS_GROW_DOWNWARD */
3609
  if (!in_regs
3610
#ifdef REG_PARM_STACK_SPACE
3611
      || REG_PARM_STACK_SPACE (fndecl) > 0
3612
#endif
3613
      )
3614
    pad_to_arg_alignment (initial_offset_ptr, boundary,
3615
                          &locate->alignment_pad);
3616
  locate->slot_offset = *initial_offset_ptr;
3617
 
3618
#ifdef PUSH_ROUNDING
3619
  if (passed_mode != BLKmode)
3620
    sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3621
#endif
3622
 
3623
  /* Pad_below needs the pre-rounded size to know how much to pad below
3624
     so this must be done before rounding up.  */
3625
  locate->offset = locate->slot_offset;
3626
  if (where_pad == downward)
3627
    pad_below (&locate->offset, passed_mode, sizetree);
3628
 
3629
  if (where_pad != none
3630
      && (!host_integerp (sizetree, 1)
3631
          || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3632
    sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3633
 
3634
  ADD_PARM_SIZE (locate->size, sizetree);
3635
 
3636
  locate->size.constant -= part_size_in_regs;
3637
#endif /* ARGS_GROW_DOWNWARD */
3638
 
3639
#ifdef FUNCTION_ARG_OFFSET
3640
  locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3641
#endif
3642
}
3643
 
3644
/* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3645
   BOUNDARY is measured in bits, but must be a multiple of a storage unit.  */
3646
 
3647
static void
3648
pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3649
                      struct args_size *alignment_pad)
3650
{
3651
  tree save_var = NULL_TREE;
3652
  HOST_WIDE_INT save_constant = 0;
3653
  int boundary_in_bytes = boundary / BITS_PER_UNIT;
3654
  HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3655
 
3656
#ifdef SPARC_STACK_BOUNDARY_HACK
3657
  /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3658
     the real alignment of %sp.  However, when it does this, the
3659
     alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY.  */
3660
  if (SPARC_STACK_BOUNDARY_HACK)
3661
    sp_offset = 0;
3662
#endif
3663
 
3664
  if (boundary > PARM_BOUNDARY)
3665
    {
3666
      save_var = offset_ptr->var;
3667
      save_constant = offset_ptr->constant;
3668
    }
3669
 
3670
  alignment_pad->var = NULL_TREE;
3671
  alignment_pad->constant = 0;
3672
 
3673
  if (boundary > BITS_PER_UNIT)
3674
    {
3675
      if (offset_ptr->var)
3676
        {
3677
          tree sp_offset_tree = ssize_int (sp_offset);
3678
          tree offset = size_binop (PLUS_EXPR,
3679
                                    ARGS_SIZE_TREE (*offset_ptr),
3680
                                    sp_offset_tree);
3681
#ifdef ARGS_GROW_DOWNWARD
3682
          tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3683
#else
3684
          tree rounded = round_up   (offset, boundary / BITS_PER_UNIT);
3685
#endif
3686
 
3687
          offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3688
          /* ARGS_SIZE_TREE includes constant term.  */
3689
          offset_ptr->constant = 0;
3690
          if (boundary > PARM_BOUNDARY)
3691
            alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3692
                                             save_var);
3693
        }
3694
      else
3695
        {
3696
          offset_ptr->constant = -sp_offset +
3697
#ifdef ARGS_GROW_DOWNWARD
3698
            FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3699
#else
3700
            CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3701
#endif
3702
            if (boundary > PARM_BOUNDARY)
3703
              alignment_pad->constant = offset_ptr->constant - save_constant;
3704
        }
3705
    }
3706
}
3707
 
3708
static void
3709
pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3710
{
3711
  if (passed_mode != BLKmode)
3712
    {
3713
      if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3714
        offset_ptr->constant
3715
          += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3716
               / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3717
              - GET_MODE_SIZE (passed_mode));
3718
    }
3719
  else
3720
    {
3721
      if (TREE_CODE (sizetree) != INTEGER_CST
3722
          || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3723
        {
3724
          /* Round the size up to multiple of PARM_BOUNDARY bits.  */
3725
          tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3726
          /* Add it in.  */
3727
          ADD_PARM_SIZE (*offset_ptr, s2);
3728
          SUB_PARM_SIZE (*offset_ptr, sizetree);
3729
        }
3730
    }
3731
}
3732
 
3733
 
3734
/* True if register REGNO was alive at a place where `setjmp' was
3735
   called and was set more than once or is an argument.  Such regs may
3736
   be clobbered by `longjmp'.  */
3737
 
3738
static bool
3739
regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3740
{
3741
  /* There appear to be cases where some local vars never reach the
3742
     backend but have bogus regnos.  */
3743
  if (regno >= max_reg_num ())
3744
    return false;
3745
 
3746
  return ((REG_N_SETS (regno) > 1
3747
           || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3748
          && REGNO_REG_SET_P (setjmp_crosses, regno));
3749
}
3750
 
3751
/* Walk the tree of blocks describing the binding levels within a
3752
   function and warn about variables the might be killed by setjmp or
3753
   vfork.  This is done after calling flow_analysis before register
3754
   allocation since that will clobber the pseudo-regs to hard
3755
   regs.  */
3756
 
3757
static void
3758
setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3759
{
3760
  tree decl, sub;
3761
 
3762
  for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3763
    {
3764
      if (TREE_CODE (decl) == VAR_DECL
3765
          && DECL_RTL_SET_P (decl)
3766
          && REG_P (DECL_RTL (decl))
3767
          && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3768
        warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3769
                 " %<longjmp%> or %<vfork%>", decl);
3770
    }
3771
 
3772
  for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3773
    setjmp_vars_warning (setjmp_crosses, sub);
3774
}
3775
 
3776
/* Do the appropriate part of setjmp_vars_warning
3777
   but for arguments instead of local variables.  */
3778
 
3779
static void
3780
setjmp_args_warning (bitmap setjmp_crosses)
3781
{
3782
  tree decl;
3783
  for (decl = DECL_ARGUMENTS (current_function_decl);
3784
       decl; decl = TREE_CHAIN (decl))
3785
    if (DECL_RTL (decl) != 0
3786
        && REG_P (DECL_RTL (decl))
3787
        && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3788
      warning (OPT_Wclobbered,
3789
               "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3790
               decl);
3791
}
3792
 
3793
/* Generate warning messages for variables live across setjmp.  */
3794
 
3795
void
3796
generate_setjmp_warnings (void)
3797
{
3798
  bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3799
 
3800
  if (n_basic_blocks == NUM_FIXED_BLOCKS
3801
      || bitmap_empty_p (setjmp_crosses))
3802
    return;
3803
 
3804
  setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3805
  setjmp_args_warning (setjmp_crosses);
3806
}
3807
 
3808
 
3809
/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3810
   and create duplicate blocks.  */
3811
/* ??? Need an option to either create block fragments or to create
3812
   abstract origin duplicates of a source block.  It really depends
3813
   on what optimization has been performed.  */
3814
 
3815
void
3816
reorder_blocks (void)
3817
{
3818
  tree block = DECL_INITIAL (current_function_decl);
3819
  VEC(tree,heap) *block_stack;
3820
 
3821
  if (block == NULL_TREE)
3822
    return;
3823
 
3824
  block_stack = VEC_alloc (tree, heap, 10);
3825
 
3826
  /* Reset the TREE_ASM_WRITTEN bit for all blocks.  */
3827
  clear_block_marks (block);
3828
 
3829
  /* Prune the old trees away, so that they don't get in the way.  */
3830
  BLOCK_SUBBLOCKS (block) = NULL_TREE;
3831
  BLOCK_CHAIN (block) = NULL_TREE;
3832
 
3833
  /* Recreate the block tree from the note nesting.  */
3834
  reorder_blocks_1 (get_insns (), block, &block_stack);
3835
  BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3836
 
3837
  VEC_free (tree, heap, block_stack);
3838
}
3839
 
3840
/* Helper function for reorder_blocks.  Reset TREE_ASM_WRITTEN.  */
3841
 
3842
void
3843
clear_block_marks (tree block)
3844
{
3845
  while (block)
3846
    {
3847
      TREE_ASM_WRITTEN (block) = 0;
3848
      clear_block_marks (BLOCK_SUBBLOCKS (block));
3849
      block = BLOCK_CHAIN (block);
3850
    }
3851
}
3852
 
3853
static void
3854
reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3855
{
3856
  rtx insn;
3857
 
3858
  for (insn = insns; insn; insn = NEXT_INSN (insn))
3859
    {
3860
      if (NOTE_P (insn))
3861
        {
3862
          if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
3863
            {
3864
              tree block = NOTE_BLOCK (insn);
3865
              tree origin;
3866
 
3867
              origin = (BLOCK_FRAGMENT_ORIGIN (block)
3868
                        ? BLOCK_FRAGMENT_ORIGIN (block)
3869
                        : block);
3870
 
3871
              /* If we have seen this block before, that means it now
3872
                 spans multiple address regions.  Create a new fragment.  */
3873
              if (TREE_ASM_WRITTEN (block))
3874
                {
3875
                  tree new_block = copy_node (block);
3876
 
3877
                  BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3878
                  BLOCK_FRAGMENT_CHAIN (new_block)
3879
                    = BLOCK_FRAGMENT_CHAIN (origin);
3880
                  BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3881
 
3882
                  NOTE_BLOCK (insn) = new_block;
3883
                  block = new_block;
3884
                }
3885
 
3886
              BLOCK_SUBBLOCKS (block) = 0;
3887
              TREE_ASM_WRITTEN (block) = 1;
3888
              /* When there's only one block for the entire function,
3889
                 current_block == block and we mustn't do this, it
3890
                 will cause infinite recursion.  */
3891
              if (block != current_block)
3892
                {
3893
                  if (block != origin)
3894
                    gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
3895
 
3896
                  BLOCK_SUPERCONTEXT (block) = current_block;
3897
                  BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3898
                  BLOCK_SUBBLOCKS (current_block) = block;
3899
                  current_block = origin;
3900
                }
3901
              VEC_safe_push (tree, heap, *p_block_stack, block);
3902
            }
3903
          else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
3904
            {
3905
              NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3906
              BLOCK_SUBBLOCKS (current_block)
3907
                = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3908
              current_block = BLOCK_SUPERCONTEXT (current_block);
3909
            }
3910
        }
3911
    }
3912
}
3913
 
3914
/* Reverse the order of elements in the chain T of blocks,
3915
   and return the new head of the chain (old last element).  */
3916
 
3917
tree
3918
blocks_nreverse (tree t)
3919
{
3920
  tree prev = 0, decl, next;
3921
  for (decl = t; decl; decl = next)
3922
    {
3923
      next = BLOCK_CHAIN (decl);
3924
      BLOCK_CHAIN (decl) = prev;
3925
      prev = decl;
3926
    }
3927
  return prev;
3928
}
3929
 
3930
/* Count the subblocks of the list starting with BLOCK.  If VECTOR is
3931
   non-NULL, list them all into VECTOR, in a depth-first preorder
3932
   traversal of the block tree.  Also clear TREE_ASM_WRITTEN in all
3933
   blocks.  */
3934
 
3935
static int
3936
all_blocks (tree block, tree *vector)
3937
{
3938
  int n_blocks = 0;
3939
 
3940
  while (block)
3941
    {
3942
      TREE_ASM_WRITTEN (block) = 0;
3943
 
3944
      /* Record this block.  */
3945
      if (vector)
3946
        vector[n_blocks] = block;
3947
 
3948
      ++n_blocks;
3949
 
3950
      /* Record the subblocks, and their subblocks...  */
3951
      n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3952
                              vector ? vector + n_blocks : 0);
3953
      block = BLOCK_CHAIN (block);
3954
    }
3955
 
3956
  return n_blocks;
3957
}
3958
 
3959
/* Return a vector containing all the blocks rooted at BLOCK.  The
3960
   number of elements in the vector is stored in N_BLOCKS_P.  The
3961
   vector is dynamically allocated; it is the caller's responsibility
3962
   to call `free' on the pointer returned.  */
3963
 
3964
static tree *
3965
get_block_vector (tree block, int *n_blocks_p)
3966
{
3967
  tree *block_vector;
3968
 
3969
  *n_blocks_p = all_blocks (block, NULL);
3970
  block_vector = XNEWVEC (tree, *n_blocks_p);
3971
  all_blocks (block, block_vector);
3972
 
3973
  return block_vector;
3974
}
3975
 
3976
static GTY(()) int next_block_index = 2;
3977
 
3978
/* Set BLOCK_NUMBER for all the blocks in FN.  */
3979
 
3980
void
3981
number_blocks (tree fn)
3982
{
3983
  int i;
3984
  int n_blocks;
3985
  tree *block_vector;
3986
 
3987
  /* For SDB and XCOFF debugging output, we start numbering the blocks
3988
     from 1 within each function, rather than keeping a running
3989
     count.  */
3990
#if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3991
  if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3992
    next_block_index = 1;
3993
#endif
3994
 
3995
  block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3996
 
3997
  /* The top-level BLOCK isn't numbered at all.  */
3998
  for (i = 1; i < n_blocks; ++i)
3999
    /* We number the blocks from two.  */
4000
    BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4001
 
4002
  free (block_vector);
4003
 
4004
  return;
4005
}
4006
 
4007
/* If VAR is present in a subblock of BLOCK, return the subblock.  */
4008
 
4009
tree
4010
debug_find_var_in_block_tree (tree var, tree block)
4011
{
4012
  tree t;
4013
 
4014
  for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4015
    if (t == var)
4016
      return block;
4017
 
4018
  for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4019
    {
4020
      tree ret = debug_find_var_in_block_tree (var, t);
4021
      if (ret)
4022
        return ret;
4023
    }
4024
 
4025
  return NULL_TREE;
4026
}
4027
 
4028
/* Keep track of whether we're in a dummy function context.  If we are,
4029
   we don't want to invoke the set_current_function hook, because we'll
4030
   get into trouble if the hook calls target_reinit () recursively or
4031
   when the initial initialization is not yet complete.  */
4032
 
4033
static bool in_dummy_function;
4034
 
4035
/* Invoke the target hook when setting cfun.  Update the optimization options
4036
   if the function uses different options than the default.  */
4037
 
4038
static void
4039
invoke_set_current_function_hook (tree fndecl)
4040
{
4041
  if (!in_dummy_function)
4042
    {
4043
      tree opts = ((fndecl)
4044
                   ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4045
                   : optimization_default_node);
4046
 
4047
      if (!opts)
4048
        opts = optimization_default_node;
4049
 
4050
      /* Change optimization options if needed.  */
4051
      if (optimization_current_node != opts)
4052
        {
4053
          optimization_current_node = opts;
4054
          cl_optimization_restore (TREE_OPTIMIZATION (opts));
4055
        }
4056
 
4057
      targetm.set_current_function (fndecl);
4058
    }
4059
}
4060
 
4061
/* cfun should never be set directly; use this function.  */
4062
 
4063
void
4064
set_cfun (struct function *new_cfun)
4065
{
4066
  if (cfun != new_cfun)
4067
    {
4068
      cfun = new_cfun;
4069
      invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4070
    }
4071
}
4072
 
4073
/* Initialized with NOGC, making this poisonous to the garbage collector.  */
4074
 
4075
static VEC(function_p,heap) *cfun_stack;
4076
 
4077
/* Push the current cfun onto the stack, and set cfun to new_cfun.  */
4078
 
4079
void
4080
push_cfun (struct function *new_cfun)
4081
{
4082
  VEC_safe_push (function_p, heap, cfun_stack, cfun);
4083
  set_cfun (new_cfun);
4084
}
4085
 
4086
/* Pop cfun from the stack.  */
4087
 
4088
void
4089
pop_cfun (void)
4090
{
4091
  struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4092
  set_cfun (new_cfun);
4093
}
4094
 
4095
/* Return value of funcdef and increase it.  */
4096
int
4097
get_next_funcdef_no (void)
4098
{
4099
  return funcdef_no++;
4100
}
4101
 
4102
/* Allocate a function structure for FNDECL and set its contents
4103
   to the defaults.  Set cfun to the newly-allocated object.
4104
   Some of the helper functions invoked during initialization assume
4105
   that cfun has already been set.  Therefore, assign the new object
4106
   directly into cfun and invoke the back end hook explicitly at the
4107
   very end, rather than initializing a temporary and calling set_cfun
4108
   on it.
4109
 
4110
   ABSTRACT_P is true if this is a function that will never be seen by
4111
   the middle-end.  Such functions are front-end concepts (like C++
4112
   function templates) that do not correspond directly to functions
4113
   placed in object files.  */
4114
 
4115
void
4116
allocate_struct_function (tree fndecl, bool abstract_p)
4117
{
4118
  tree result;
4119
  tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4120
 
4121
  cfun = GGC_CNEW (struct function);
4122
 
4123
  cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
4124
 
4125
  init_eh_for_function ();
4126
 
4127
  if (init_machine_status)
4128
    cfun->machine = (*init_machine_status) ();
4129
 
4130
#ifdef OVERRIDE_ABI_FORMAT
4131
  OVERRIDE_ABI_FORMAT (fndecl);
4132
#endif
4133
 
4134
  invoke_set_current_function_hook (fndecl);
4135
 
4136
  if (fndecl != NULL_TREE)
4137
    {
4138
      DECL_STRUCT_FUNCTION (fndecl) = cfun;
4139
      cfun->decl = fndecl;
4140
      current_function_funcdef_no = get_next_funcdef_no ();
4141
 
4142
      result = DECL_RESULT (fndecl);
4143
      if (!abstract_p && aggregate_value_p (result, fndecl))
4144
        {
4145
#ifdef PCC_STATIC_STRUCT_RETURN
4146
          cfun->returns_pcc_struct = 1;
4147
#endif
4148
          cfun->returns_struct = 1;
4149
        }
4150
 
4151
      cfun->stdarg
4152
        = (fntype
4153
           && TYPE_ARG_TYPES (fntype) != 0
4154
           && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4155
               != void_type_node));
4156
 
4157
      /* Assume all registers in stdarg functions need to be saved.  */
4158
      cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4159
      cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4160
    }
4161
}
4162
 
4163
/* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4164
   instead of just setting it.  */
4165
 
4166
void
4167
push_struct_function (tree fndecl)
4168
{
4169
  VEC_safe_push (function_p, heap, cfun_stack, cfun);
4170
  allocate_struct_function (fndecl, false);
4171
}
4172
 
4173
/* Reset cfun, and other non-struct-function variables to defaults as
4174
   appropriate for emitting rtl at the start of a function.  */
4175
 
4176
static void
4177
prepare_function_start (void)
4178
{
4179
  gcc_assert (!crtl->emit.x_last_insn);
4180
  init_temp_slots ();
4181
  init_emit ();
4182
  init_varasm_status ();
4183
  init_expr ();
4184
  default_rtl_profile ();
4185
 
4186
  cse_not_expected = ! optimize;
4187
 
4188
  /* Caller save not needed yet.  */
4189
  caller_save_needed = 0;
4190
 
4191
  /* We haven't done register allocation yet.  */
4192
  reg_renumber = 0;
4193
 
4194
  /* Indicate that we have not instantiated virtual registers yet.  */
4195
  virtuals_instantiated = 0;
4196
 
4197
  /* Indicate that we want CONCATs now.  */
4198
  generating_concat_p = 1;
4199
 
4200
  /* Indicate we have no need of a frame pointer yet.  */
4201
  frame_pointer_needed = 0;
4202
}
4203
 
4204
/* Initialize the rtl expansion mechanism so that we can do simple things
4205
   like generate sequences.  This is used to provide a context during global
4206
   initialization of some passes.  You must call expand_dummy_function_end
4207
   to exit this context.  */
4208
 
4209
void
4210
init_dummy_function_start (void)
4211
{
4212
  gcc_assert (!in_dummy_function);
4213
  in_dummy_function = true;
4214
  push_struct_function (NULL_TREE);
4215
  prepare_function_start ();
4216
}
4217
 
4218
/* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4219
   and initialize static variables for generating RTL for the statements
4220
   of the function.  */
4221
 
4222
void
4223
init_function_start (tree subr)
4224
{
4225
  if (subr && DECL_STRUCT_FUNCTION (subr))
4226
    set_cfun (DECL_STRUCT_FUNCTION (subr));
4227
  else
4228
    allocate_struct_function (subr, false);
4229
  prepare_function_start ();
4230
 
4231
  /* Warn if this value is an aggregate type,
4232
     regardless of which calling convention we are using for it.  */
4233
  if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4234
    warning (OPT_Waggregate_return, "function returns an aggregate");
4235
}
4236
 
4237
/* Make sure all values used by the optimization passes have sane defaults.  */
4238
unsigned int
4239
init_function_for_compilation (void)
4240
{
4241
  reg_renumber = 0;
4242
  return 0;
4243
}
4244
 
4245
struct rtl_opt_pass pass_init_function =
4246
{
4247
 {
4248
  RTL_PASS,
4249
  "*init_function",                     /* name */
4250
  NULL,                                 /* gate */
4251
  init_function_for_compilation,        /* execute */
4252
  NULL,                                 /* sub */
4253
  NULL,                                 /* next */
4254
  0,                                    /* static_pass_number */
4255
  TV_NONE,                              /* tv_id */
4256
  0,                                    /* properties_required */
4257
  0,                                    /* properties_provided */
4258
  0,                                    /* properties_destroyed */
4259
  0,                                    /* todo_flags_start */
4260
 
4261
 }
4262
};
4263
 
4264
 
4265
void
4266
expand_main_function (void)
4267
{
4268
#if (defined(INVOKE__main)                              \
4269
     || (!defined(HAS_INIT_SECTION)                     \
4270
         && !defined(INIT_SECTION_ASM_OP)               \
4271
         && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4272
  emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4273
#endif
4274
}
4275
 
4276
/* Expand code to initialize the stack_protect_guard.  This is invoked at
4277
   the beginning of a function to be protected.  */
4278
 
4279
#ifndef HAVE_stack_protect_set
4280
# define HAVE_stack_protect_set         0
4281
# define gen_stack_protect_set(x,y)     (gcc_unreachable (), NULL_RTX)
4282
#endif
4283
 
4284
void
4285
stack_protect_prologue (void)
4286
{
4287
  tree guard_decl = targetm.stack_protect_guard ();
4288
  rtx x, y;
4289
 
4290
  x = expand_normal (crtl->stack_protect_guard);
4291
  y = expand_normal (guard_decl);
4292
 
4293
  /* Allow the target to copy from Y to X without leaking Y into a
4294
     register.  */
4295
  if (HAVE_stack_protect_set)
4296
    {
4297
      rtx insn = gen_stack_protect_set (x, y);
4298
      if (insn)
4299
        {
4300
          emit_insn (insn);
4301
          return;
4302
        }
4303
    }
4304
 
4305
  /* Otherwise do a straight move.  */
4306
  emit_move_insn (x, y);
4307
}
4308
 
4309
/* Expand code to verify the stack_protect_guard.  This is invoked at
4310
   the end of a function to be protected.  */
4311
 
4312
#ifndef HAVE_stack_protect_test
4313
# define HAVE_stack_protect_test                0
4314
# define gen_stack_protect_test(x, y, z)        (gcc_unreachable (), NULL_RTX)
4315
#endif
4316
 
4317
void
4318
stack_protect_epilogue (void)
4319
{
4320
  tree guard_decl = targetm.stack_protect_guard ();
4321
  rtx label = gen_label_rtx ();
4322
  rtx x, y, tmp;
4323
 
4324
  x = expand_normal (crtl->stack_protect_guard);
4325
  y = expand_normal (guard_decl);
4326
 
4327
  /* Allow the target to compare Y with X without leaking either into
4328
     a register.  */
4329
  switch (HAVE_stack_protect_test != 0)
4330
    {
4331
    case 1:
4332
      tmp = gen_stack_protect_test (x, y, label);
4333
      if (tmp)
4334
        {
4335
          emit_insn (tmp);
4336
          break;
4337
        }
4338
      /* FALLTHRU */
4339
 
4340
    default:
4341
      emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4342
      break;
4343
    }
4344
 
4345
  /* The noreturn predictor has been moved to the tree level.  The rtl-level
4346
     predictors estimate this branch about 20%, which isn't enough to get
4347
     things moved out of line.  Since this is the only extant case of adding
4348
     a noreturn function at the rtl level, it doesn't seem worth doing ought
4349
     except adding the prediction by hand.  */
4350
  tmp = get_last_insn ();
4351
  if (JUMP_P (tmp))
4352
    predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4353
 
4354
  expand_expr_stmt (targetm.stack_protect_fail ());
4355
  emit_label (label);
4356
}
4357
 
4358
/* Start the RTL for a new function, and set variables used for
4359
   emitting RTL.
4360
   SUBR is the FUNCTION_DECL node.
4361
   PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4362
   the function's parameters, which must be run at any return statement.  */
4363
 
4364
void
4365
expand_function_start (tree subr)
4366
{
4367
  /* Make sure volatile mem refs aren't considered
4368
     valid operands of arithmetic insns.  */
4369
  init_recog_no_volatile ();
4370
 
4371
  crtl->profile
4372
    = (profile_flag
4373
       && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4374
 
4375
  crtl->limit_stack
4376
    = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4377
 
4378
  /* Make the label for return statements to jump to.  Do not special
4379
     case machines with special return instructions -- they will be
4380
     handled later during jump, ifcvt, or epilogue creation.  */
4381
  return_label = gen_label_rtx ();
4382
 
4383
  /* Initialize rtx used to return the value.  */
4384
  /* Do this before assign_parms so that we copy the struct value address
4385
     before any library calls that assign parms might generate.  */
4386
 
4387
  /* Decide whether to return the value in memory or in a register.  */
4388
  if (aggregate_value_p (DECL_RESULT (subr), subr))
4389
    {
4390
      /* Returning something that won't go in a register.  */
4391
      rtx value_address = 0;
4392
 
4393
#ifdef PCC_STATIC_STRUCT_RETURN
4394
      if (cfun->returns_pcc_struct)
4395
        {
4396
          int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4397
          value_address = assemble_static_space (size);
4398
        }
4399
      else
4400
#endif
4401
        {
4402
          rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4403
          /* Expect to be passed the address of a place to store the value.
4404
             If it is passed as an argument, assign_parms will take care of
4405
             it.  */
4406
          if (sv)
4407
            {
4408
              value_address = gen_reg_rtx (Pmode);
4409
              emit_move_insn (value_address, sv);
4410
            }
4411
        }
4412
      if (value_address)
4413
        {
4414
          rtx x = value_address;
4415
          if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4416
            {
4417
              x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4418
              set_mem_attributes (x, DECL_RESULT (subr), 1);
4419
            }
4420
          SET_DECL_RTL (DECL_RESULT (subr), x);
4421
        }
4422
    }
4423
  else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4424
    /* If return mode is void, this decl rtl should not be used.  */
4425
    SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4426
  else
4427
    {
4428
      /* Compute the return values into a pseudo reg, which we will copy
4429
         into the true return register after the cleanups are done.  */
4430
      tree return_type = TREE_TYPE (DECL_RESULT (subr));
4431
      if (TYPE_MODE (return_type) != BLKmode
4432
          && targetm.calls.return_in_msb (return_type))
4433
        /* expand_function_end will insert the appropriate padding in
4434
           this case.  Use the return value's natural (unpadded) mode
4435
           within the function proper.  */
4436
        SET_DECL_RTL (DECL_RESULT (subr),
4437
                      gen_reg_rtx (TYPE_MODE (return_type)));
4438
      else
4439
        {
4440
          /* In order to figure out what mode to use for the pseudo, we
4441
             figure out what the mode of the eventual return register will
4442
             actually be, and use that.  */
4443
          rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4444
 
4445
          /* Structures that are returned in registers are not
4446
             aggregate_value_p, so we may see a PARALLEL or a REG.  */
4447
          if (REG_P (hard_reg))
4448
            SET_DECL_RTL (DECL_RESULT (subr),
4449
                          gen_reg_rtx (GET_MODE (hard_reg)));
4450
          else
4451
            {
4452
              gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4453
              SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4454
            }
4455
        }
4456
 
4457
      /* Set DECL_REGISTER flag so that expand_function_end will copy the
4458
         result to the real return register(s).  */
4459
      DECL_REGISTER (DECL_RESULT (subr)) = 1;
4460
    }
4461
 
4462
  /* Initialize rtx for parameters and local variables.
4463
     In some cases this requires emitting insns.  */
4464
  assign_parms (subr);
4465
 
4466
  /* If function gets a static chain arg, store it.  */
4467
  if (cfun->static_chain_decl)
4468
    {
4469
      tree parm = cfun->static_chain_decl;
4470
      rtx local, chain, insn;
4471
 
4472
      local = gen_reg_rtx (Pmode);
4473
      chain = targetm.calls.static_chain (current_function_decl, true);
4474
 
4475
      set_decl_incoming_rtl (parm, chain, false);
4476
      SET_DECL_RTL (parm, local);
4477
      mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4478
 
4479
      insn = emit_move_insn (local, chain);
4480
 
4481
      /* Mark the register as eliminable, similar to parameters.  */
4482
      if (MEM_P (chain)
4483
          && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4484
        set_unique_reg_note (insn, REG_EQUIV, chain);
4485
    }
4486
 
4487
  /* If the function receives a non-local goto, then store the
4488
     bits we need to restore the frame pointer.  */
4489
  if (cfun->nonlocal_goto_save_area)
4490
    {
4491
      tree t_save;
4492
      rtx r_save;
4493
 
4494
      /* ??? We need to do this save early.  Unfortunately here is
4495
         before the frame variable gets declared.  Help out...  */
4496
      tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4497
      if (!DECL_RTL_SET_P (var))
4498
        expand_decl (var);
4499
 
4500
      t_save = build4 (ARRAY_REF, ptr_type_node,
4501
                       cfun->nonlocal_goto_save_area,
4502
                       integer_zero_node, NULL_TREE, NULL_TREE);
4503
      r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4504
      r_save = convert_memory_address (Pmode, r_save);
4505
 
4506
      emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4507
      update_nonlocal_goto_save_area ();
4508
    }
4509
 
4510
  /* The following was moved from init_function_start.
4511
     The move is supposed to make sdb output more accurate.  */
4512
  /* Indicate the beginning of the function body,
4513
     as opposed to parm setup.  */
4514
  emit_note (NOTE_INSN_FUNCTION_BEG);
4515
 
4516
  gcc_assert (NOTE_P (get_last_insn ()));
4517
 
4518
  parm_birth_insn = get_last_insn ();
4519
 
4520
  if (crtl->profile)
4521
    {
4522
#ifdef PROFILE_HOOK
4523
      PROFILE_HOOK (current_function_funcdef_no);
4524
#endif
4525
    }
4526
 
4527
  /* After the display initializations is where the stack checking
4528
     probe should go.  */
4529
  if(flag_stack_check)
4530
    stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4531
 
4532
  /* Make sure there is a line number after the function entry setup code.  */
4533
  force_next_line_note ();
4534
}
4535
 
4536
/* Undo the effects of init_dummy_function_start.  */
4537
void
4538
expand_dummy_function_end (void)
4539
{
4540
  gcc_assert (in_dummy_function);
4541
 
4542
  /* End any sequences that failed to be closed due to syntax errors.  */
4543
  while (in_sequence_p ())
4544
    end_sequence ();
4545
 
4546
  /* Outside function body, can't compute type's actual size
4547
     until next function's body starts.  */
4548
 
4549
  free_after_parsing (cfun);
4550
  free_after_compilation (cfun);
4551
  pop_cfun ();
4552
  in_dummy_function = false;
4553
}
4554
 
4555
/* Call DOIT for each hard register used as a return value from
4556
   the current function.  */
4557
 
4558
void
4559
diddle_return_value (void (*doit) (rtx, void *), void *arg)
4560
{
4561
  rtx outgoing = crtl->return_rtx;
4562
 
4563
  if (! outgoing)
4564
    return;
4565
 
4566
  if (REG_P (outgoing))
4567
    (*doit) (outgoing, arg);
4568
  else if (GET_CODE (outgoing) == PARALLEL)
4569
    {
4570
      int i;
4571
 
4572
      for (i = 0; i < XVECLEN (outgoing, 0); i++)
4573
        {
4574
          rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4575
 
4576
          if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4577
            (*doit) (x, arg);
4578
        }
4579
    }
4580
}
4581
 
4582
static void
4583
do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4584
{
4585
  emit_clobber (reg);
4586
}
4587
 
4588
void
4589
clobber_return_register (void)
4590
{
4591
  diddle_return_value (do_clobber_return_reg, NULL);
4592
 
4593
  /* In case we do use pseudo to return value, clobber it too.  */
4594
  if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4595
    {
4596
      tree decl_result = DECL_RESULT (current_function_decl);
4597
      rtx decl_rtl = DECL_RTL (decl_result);
4598
      if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4599
        {
4600
          do_clobber_return_reg (decl_rtl, NULL);
4601
        }
4602
    }
4603
}
4604
 
4605
static void
4606
do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4607
{
4608
  emit_use (reg);
4609
}
4610
 
4611
static void
4612
use_return_register (void)
4613
{
4614
  diddle_return_value (do_use_return_reg, NULL);
4615
}
4616
 
4617
/* Possibly warn about unused parameters.  */
4618
void
4619
do_warn_unused_parameter (tree fn)
4620
{
4621
  tree decl;
4622
 
4623
  for (decl = DECL_ARGUMENTS (fn);
4624
       decl; decl = TREE_CHAIN (decl))
4625
    if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4626
        && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4627
        && !TREE_NO_WARNING (decl))
4628
      warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4629
}
4630
 
4631
static GTY(()) rtx initial_trampoline;
4632
 
4633
/* Generate RTL for the end of the current function.  */
4634
 
4635
void
4636
expand_function_end (void)
4637
{
4638
  rtx clobber_after;
4639
 
4640
  /* If arg_pointer_save_area was referenced only from a nested
4641
     function, we will not have initialized it yet.  Do that now.  */
4642
  if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4643
    get_arg_pointer_save_area ();
4644
 
4645
  /* If we are doing generic stack checking and this function makes calls,
4646
     do a stack probe at the start of the function to ensure we have enough
4647
     space for another stack frame.  */
4648
  if (flag_stack_check == GENERIC_STACK_CHECK)
4649
    {
4650
      rtx insn, seq;
4651
 
4652
      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4653
        if (CALL_P (insn))
4654
          {
4655
            rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4656
            start_sequence ();
4657
            if (STACK_CHECK_MOVING_SP)
4658
              anti_adjust_stack_and_probe (max_frame_size, true);
4659
            else
4660
              probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4661
            seq = get_insns ();
4662
            end_sequence ();
4663
            emit_insn_before (seq, stack_check_probe_note);
4664
            break;
4665
          }
4666
    }
4667
 
4668
  /* End any sequences that failed to be closed due to syntax errors.  */
4669
  while (in_sequence_p ())
4670
    end_sequence ();
4671
 
4672
  clear_pending_stack_adjust ();
4673
  do_pending_stack_adjust ();
4674
 
4675
  /* Output a linenumber for the end of the function.
4676
     SDB depends on this.  */
4677
  force_next_line_note ();
4678
  set_curr_insn_source_location (input_location);
4679
 
4680
  /* Before the return label (if any), clobber the return
4681
     registers so that they are not propagated live to the rest of
4682
     the function.  This can only happen with functions that drop
4683
     through; if there had been a return statement, there would
4684
     have either been a return rtx, or a jump to the return label.
4685
 
4686
     We delay actual code generation after the current_function_value_rtx
4687
     is computed.  */
4688
  clobber_after = get_last_insn ();
4689
 
4690
  /* Output the label for the actual return from the function.  */
4691
  emit_label (return_label);
4692
 
4693
  if (USING_SJLJ_EXCEPTIONS)
4694
    {
4695
      /* Let except.c know where it should emit the call to unregister
4696
         the function context for sjlj exceptions.  */
4697
      if (flag_exceptions)
4698
        sjlj_emit_function_exit_after (get_last_insn ());
4699
    }
4700
  else
4701
    {
4702
      /* We want to ensure that instructions that may trap are not
4703
         moved into the epilogue by scheduling, because we don't
4704
         always emit unwind information for the epilogue.  */
4705
      if (flag_non_call_exceptions)
4706
        emit_insn (gen_blockage ());
4707
    }
4708
 
4709
  /* If this is an implementation of throw, do what's necessary to
4710
     communicate between __builtin_eh_return and the epilogue.  */
4711
  expand_eh_return ();
4712
 
4713
  /* If scalar return value was computed in a pseudo-reg, or was a named
4714
     return value that got dumped to the stack, copy that to the hard
4715
     return register.  */
4716
  if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4717
    {
4718
      tree decl_result = DECL_RESULT (current_function_decl);
4719
      rtx decl_rtl = DECL_RTL (decl_result);
4720
 
4721
      if (REG_P (decl_rtl)
4722
          ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4723
          : DECL_REGISTER (decl_result))
4724
        {
4725
          rtx real_decl_rtl = crtl->return_rtx;
4726
 
4727
          /* This should be set in assign_parms.  */
4728
          gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4729
 
4730
          /* If this is a BLKmode structure being returned in registers,
4731
             then use the mode computed in expand_return.  Note that if
4732
             decl_rtl is memory, then its mode may have been changed,
4733
             but that crtl->return_rtx has not.  */
4734
          if (GET_MODE (real_decl_rtl) == BLKmode)
4735
            PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4736
 
4737
          /* If a non-BLKmode return value should be padded at the least
4738
             significant end of the register, shift it left by the appropriate
4739
             amount.  BLKmode results are handled using the group load/store
4740
             machinery.  */
4741
          if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4742
              && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4743
            {
4744
              emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4745
                                           REGNO (real_decl_rtl)),
4746
                              decl_rtl);
4747
              shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4748
            }
4749
          /* If a named return value dumped decl_return to memory, then
4750
             we may need to re-do the PROMOTE_MODE signed/unsigned
4751
             extension.  */
4752
          else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4753
            {
4754
              int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4755
              promote_function_mode (TREE_TYPE (decl_result),
4756
                                     GET_MODE (decl_rtl), &unsignedp,
4757
                                     TREE_TYPE (current_function_decl), 1);
4758
 
4759
              convert_move (real_decl_rtl, decl_rtl, unsignedp);
4760
            }
4761
          else if (GET_CODE (real_decl_rtl) == PARALLEL)
4762
            {
4763
              /* If expand_function_start has created a PARALLEL for decl_rtl,
4764
                 move the result to the real return registers.  Otherwise, do
4765
                 a group load from decl_rtl for a named return.  */
4766
              if (GET_CODE (decl_rtl) == PARALLEL)
4767
                emit_group_move (real_decl_rtl, decl_rtl);
4768
              else
4769
                emit_group_load (real_decl_rtl, decl_rtl,
4770
                                 TREE_TYPE (decl_result),
4771
                                 int_size_in_bytes (TREE_TYPE (decl_result)));
4772
            }
4773
          /* In the case of complex integer modes smaller than a word, we'll
4774
             need to generate some non-trivial bitfield insertions.  Do that
4775
             on a pseudo and not the hard register.  */
4776
          else if (GET_CODE (decl_rtl) == CONCAT
4777
                   && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4778
                   && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4779
            {
4780
              int old_generating_concat_p;
4781
              rtx tmp;
4782
 
4783
              old_generating_concat_p = generating_concat_p;
4784
              generating_concat_p = 0;
4785
              tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4786
              generating_concat_p = old_generating_concat_p;
4787
 
4788
              emit_move_insn (tmp, decl_rtl);
4789
              emit_move_insn (real_decl_rtl, tmp);
4790
            }
4791
          else
4792
            emit_move_insn (real_decl_rtl, decl_rtl);
4793
        }
4794
    }
4795
 
4796
  /* If returning a structure, arrange to return the address of the value
4797
     in a place where debuggers expect to find it.
4798
 
4799
     If returning a structure PCC style,
4800
     the caller also depends on this value.
4801
     And cfun->returns_pcc_struct is not necessarily set.  */
4802
  if (cfun->returns_struct
4803
      || cfun->returns_pcc_struct)
4804
    {
4805
      rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4806
      tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4807
      rtx outgoing;
4808
 
4809
      if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4810
        type = TREE_TYPE (type);
4811
      else
4812
        value_address = XEXP (value_address, 0);
4813
 
4814
      outgoing = targetm.calls.function_value (build_pointer_type (type),
4815
                                               current_function_decl, true);
4816
 
4817
      /* Mark this as a function return value so integrate will delete the
4818
         assignment and USE below when inlining this function.  */
4819
      REG_FUNCTION_VALUE_P (outgoing) = 1;
4820
 
4821
      /* The address may be ptr_mode and OUTGOING may be Pmode.  */
4822
      value_address = convert_memory_address (GET_MODE (outgoing),
4823
                                              value_address);
4824
 
4825
      emit_move_insn (outgoing, value_address);
4826
 
4827
      /* Show return register used to hold result (in this case the address
4828
         of the result.  */
4829
      crtl->return_rtx = outgoing;
4830
    }
4831
 
4832
  /* Emit the actual code to clobber return register.  */
4833
  {
4834
    rtx seq;
4835
 
4836
    start_sequence ();
4837
    clobber_return_register ();
4838
    seq = get_insns ();
4839
    end_sequence ();
4840
 
4841
    emit_insn_after (seq, clobber_after);
4842
  }
4843
 
4844
  /* Output the label for the naked return from the function.  */
4845
  if (naked_return_label)
4846
    emit_label (naked_return_label);
4847
 
4848
  /* @@@ This is a kludge.  We want to ensure that instructions that
4849
     may trap are not moved into the epilogue by scheduling, because
4850
     we don't always emit unwind information for the epilogue.  */
4851
  if (! USING_SJLJ_EXCEPTIONS && flag_non_call_exceptions)
4852
    emit_insn (gen_blockage ());
4853
 
4854
  /* If stack protection is enabled for this function, check the guard.  */
4855
  if (crtl->stack_protect_guard)
4856
    stack_protect_epilogue ();
4857
 
4858
  /* If we had calls to alloca, and this machine needs
4859
     an accurate stack pointer to exit the function,
4860
     insert some code to save and restore the stack pointer.  */
4861
  if (! EXIT_IGNORE_STACK
4862
      && cfun->calls_alloca)
4863
    {
4864
      rtx tem = 0;
4865
 
4866
      emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4867
      emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4868
    }
4869
 
4870
  /* ??? This should no longer be necessary since stupid is no longer with
4871
     us, but there are some parts of the compiler (eg reload_combine, and
4872
     sh mach_dep_reorg) that still try and compute their own lifetime info
4873
     instead of using the general framework.  */
4874
  use_return_register ();
4875
}
4876
 
4877
rtx
4878
get_arg_pointer_save_area (void)
4879
{
4880
  rtx ret = arg_pointer_save_area;
4881
 
4882
  if (! ret)
4883
    {
4884
      ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4885
      arg_pointer_save_area = ret;
4886
    }
4887
 
4888
  if (! crtl->arg_pointer_save_area_init)
4889
    {
4890
      rtx seq;
4891
 
4892
      /* Save the arg pointer at the beginning of the function.  The
4893
         generated stack slot may not be a valid memory address, so we
4894
         have to check it and fix it if necessary.  */
4895
      start_sequence ();
4896
      emit_move_insn (validize_mem (ret),
4897
                      crtl->args.internal_arg_pointer);
4898
      seq = get_insns ();
4899
      end_sequence ();
4900
 
4901
      push_topmost_sequence ();
4902
      emit_insn_after (seq, entry_of_function ());
4903
      pop_topmost_sequence ();
4904
    }
4905
 
4906
  return ret;
4907
}
4908
 
4909
/* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4910
   for the first time.  */
4911
 
4912
static void
4913
record_insns (rtx insns, rtx end, htab_t *hashp)
4914
{
4915
  rtx tmp;
4916
  htab_t hash = *hashp;
4917
 
4918
  if (hash == NULL)
4919
    *hashp = hash
4920
      = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
4921
 
4922
  for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
4923
    {
4924
      void **slot = htab_find_slot (hash, tmp, INSERT);
4925
      gcc_assert (*slot == NULL);
4926
      *slot = tmp;
4927
    }
4928
}
4929
 
4930
/* INSN has been duplicated as COPY, as part of duping a basic block.
4931
   If INSN is an epilogue insn, then record COPY as epilogue as well.  */
4932
 
4933
void
4934
maybe_copy_epilogue_insn (rtx insn, rtx copy)
4935
{
4936
  void **slot;
4937
 
4938
  if (epilogue_insn_hash == NULL
4939
      || htab_find (epilogue_insn_hash, insn) == NULL)
4940
    return;
4941
 
4942
  slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
4943
  gcc_assert (*slot == NULL);
4944
  *slot = copy;
4945
}
4946
 
4947
/* Set the locator of the insn chain starting at INSN to LOC.  */
4948
static void
4949
set_insn_locators (rtx insn, int loc)
4950
{
4951
  while (insn != NULL_RTX)
4952
    {
4953
      if (INSN_P (insn))
4954
        INSN_LOCATOR (insn) = loc;
4955
      insn = NEXT_INSN (insn);
4956
    }
4957
}
4958
 
4959
/* Determine if any INSNs in HASH are, or are part of, INSN.  Because
4960
   we can be running after reorg, SEQUENCE rtl is possible.  */
4961
 
4962
static bool
4963
contains (const_rtx insn, htab_t hash)
4964
{
4965
  if (hash == NULL)
4966
    return false;
4967
 
4968
  if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
4969
    {
4970
      int i;
4971
      for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4972
        if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
4973
          return true;
4974
      return false;
4975
    }
4976
 
4977
  return htab_find (hash, insn) != NULL;
4978
}
4979
 
4980
int
4981
prologue_epilogue_contains (const_rtx insn)
4982
{
4983
  if (contains (insn, prologue_insn_hash))
4984
    return 1;
4985
  if (contains (insn, epilogue_insn_hash))
4986
    return 1;
4987
  return 0;
4988
}
4989
 
4990
#ifdef HAVE_return
4991
/* Insert gen_return at the end of block BB.  This also means updating
4992
   block_for_insn appropriately.  */
4993
 
4994
static void
4995
emit_return_into_block (basic_block bb)
4996
{
4997
  emit_jump_insn_after (gen_return (), BB_END (bb));
4998
}
4999
#endif /* HAVE_return */
5000
 
5001
/* Generate the prologue and epilogue RTL if the machine supports it.  Thread
5002
   this into place with notes indicating where the prologue ends and where
5003
   the epilogue begins.  Update the basic block information when possible.  */
5004
 
5005
static void
5006
thread_prologue_and_epilogue_insns (void)
5007
{
5008
  int inserted = 0;
5009
  edge e;
5010
#if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5011
  rtx seq;
5012
#endif
5013
#if defined (HAVE_epilogue) || defined(HAVE_return)
5014
  rtx epilogue_end = NULL_RTX;
5015
#endif
5016
  edge_iterator ei;
5017
 
5018
  rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5019
#ifdef HAVE_prologue
5020
  if (HAVE_prologue)
5021
    {
5022
      start_sequence ();
5023
      seq = gen_prologue ();
5024
      emit_insn (seq);
5025
 
5026
      /* Insert an explicit USE for the frame pointer
5027
         if the profiling is on and the frame pointer is required.  */
5028
      if (crtl->profile && frame_pointer_needed)
5029
        emit_use (hard_frame_pointer_rtx);
5030
 
5031
      /* Retain a map of the prologue insns.  */
5032
      record_insns (seq, NULL, &prologue_insn_hash);
5033
      emit_note (NOTE_INSN_PROLOGUE_END);
5034
 
5035
#ifndef PROFILE_BEFORE_PROLOGUE
5036
      /* Ensure that instructions are not moved into the prologue when
5037
         profiling is on.  The call to the profiling routine can be
5038
         emitted within the live range of a call-clobbered register.  */
5039
      if (crtl->profile)
5040
        emit_insn (gen_blockage ());
5041
#endif
5042
 
5043
      seq = get_insns ();
5044
      end_sequence ();
5045
      set_insn_locators (seq, prologue_locator);
5046
 
5047
      /* Can't deal with multiple successors of the entry block
5048
         at the moment.  Function should always have at least one
5049
         entry point.  */
5050
      gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5051
 
5052
      insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5053
      inserted = 1;
5054
    }
5055
#endif
5056
 
5057
  /* If the exit block has no non-fake predecessors, we don't need
5058
     an epilogue.  */
5059
  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5060
    if ((e->flags & EDGE_FAKE) == 0)
5061
      break;
5062
  if (e == NULL)
5063
    goto epilogue_done;
5064
 
5065
  rtl_profile_for_bb (EXIT_BLOCK_PTR);
5066
#ifdef HAVE_return
5067
  if (optimize && HAVE_return)
5068
    {
5069
      /* If we're allowed to generate a simple return instruction,
5070
         then by definition we don't need a full epilogue.  Examine
5071
         the block that falls through to EXIT.   If it does not
5072
         contain any code, examine its predecessors and try to
5073
         emit (conditional) return instructions.  */
5074
 
5075
      basic_block last;
5076
      rtx label;
5077
 
5078
      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5079
        if (e->flags & EDGE_FALLTHRU)
5080
          break;
5081
      if (e == NULL)
5082
        goto epilogue_done;
5083
      last = e->src;
5084
 
5085
      /* Verify that there are no active instructions in the last block.  */
5086
      label = BB_END (last);
5087
      while (label && !LABEL_P (label))
5088
        {
5089
          if (active_insn_p (label))
5090
            break;
5091
          label = PREV_INSN (label);
5092
        }
5093
 
5094
      if (BB_HEAD (last) == label && LABEL_P (label))
5095
        {
5096
          edge_iterator ei2;
5097
 
5098
          for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5099
            {
5100
              basic_block bb = e->src;
5101
              rtx jump;
5102
 
5103
              if (bb == ENTRY_BLOCK_PTR)
5104
                {
5105
                  ei_next (&ei2);
5106
                  continue;
5107
                }
5108
 
5109
              jump = BB_END (bb);
5110
              if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5111
                {
5112
                  ei_next (&ei2);
5113
                  continue;
5114
                }
5115
 
5116
              /* If we have an unconditional jump, we can replace that
5117
                 with a simple return instruction.  */
5118
              if (simplejump_p (jump))
5119
                {
5120
                  emit_return_into_block (bb);
5121
                  delete_insn (jump);
5122
                }
5123
 
5124
              /* If we have a conditional jump, we can try to replace
5125
                 that with a conditional return instruction.  */
5126
              else if (condjump_p (jump))
5127
                {
5128
                  if (! redirect_jump (jump, 0, 0))
5129
                    {
5130
                      ei_next (&ei2);
5131
                      continue;
5132
                    }
5133
 
5134
                  /* If this block has only one successor, it both jumps
5135
                     and falls through to the fallthru block, so we can't
5136
                     delete the edge.  */
5137
                  if (single_succ_p (bb))
5138
                    {
5139
                      ei_next (&ei2);
5140
                      continue;
5141
                    }
5142
                }
5143
              else
5144
                {
5145
                  ei_next (&ei2);
5146
                  continue;
5147
                }
5148
 
5149
              /* Fix up the CFG for the successful change we just made.  */
5150
              redirect_edge_succ (e, EXIT_BLOCK_PTR);
5151
            }
5152
 
5153
          /* Emit a return insn for the exit fallthru block.  Whether
5154
             this is still reachable will be determined later.  */
5155
 
5156
          emit_barrier_after (BB_END (last));
5157
          emit_return_into_block (last);
5158
          epilogue_end = BB_END (last);
5159
          single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5160
          goto epilogue_done;
5161
        }
5162
    }
5163
#endif
5164
 
5165
  /* A small fib -- epilogue is not yet completed, but we wish to re-use
5166
     this marker for the splits of EH_RETURN patterns, and nothing else
5167
     uses the flag in the meantime.  */
5168
  epilogue_completed = 1;
5169
 
5170
#ifdef HAVE_eh_return
5171
  /* Find non-fallthru edges that end with EH_RETURN instructions.  On
5172
     some targets, these get split to a special version of the epilogue
5173
     code.  In order to be able to properly annotate these with unwind
5174
     info, try to split them now.  If we get a valid split, drop an
5175
     EPILOGUE_BEG note and mark the insns as epilogue insns.  */
5176
  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5177
    {
5178
      rtx prev, last, trial;
5179
 
5180
      if (e->flags & EDGE_FALLTHRU)
5181
        continue;
5182
      last = BB_END (e->src);
5183
      if (!eh_returnjump_p (last))
5184
        continue;
5185
 
5186
      prev = PREV_INSN (last);
5187
      trial = try_split (PATTERN (last), last, 1);
5188
      if (trial == last)
5189
        continue;
5190
 
5191
      record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5192
      emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5193
    }
5194
#endif
5195
 
5196
  /* Find the edge that falls through to EXIT.  Other edges may exist
5197
     due to RETURN instructions, but those don't need epilogues.
5198
     There really shouldn't be a mixture -- either all should have
5199
     been converted or none, however...  */
5200
 
5201
  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5202
    if (e->flags & EDGE_FALLTHRU)
5203
      break;
5204
  if (e == NULL)
5205
    goto epilogue_done;
5206
 
5207
#ifdef HAVE_epilogue
5208
  if (HAVE_epilogue)
5209
    {
5210
      start_sequence ();
5211
      epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5212
      seq = gen_epilogue ();
5213
      emit_jump_insn (seq);
5214
 
5215
      /* Retain a map of the epilogue insns.  */
5216
      record_insns (seq, NULL, &epilogue_insn_hash);
5217
      set_insn_locators (seq, epilogue_locator);
5218
 
5219
      seq = get_insns ();
5220
      end_sequence ();
5221
 
5222
      insert_insn_on_edge (seq, e);
5223
      inserted = 1;
5224
    }
5225
  else
5226
#endif
5227
    {
5228
      basic_block cur_bb;
5229
 
5230
      if (! next_active_insn (BB_END (e->src)))
5231
        goto epilogue_done;
5232
      /* We have a fall-through edge to the exit block, the source is not
5233
         at the end of the function, and there will be an assembler epilogue
5234
         at the end of the function.
5235
         We can't use force_nonfallthru here, because that would try to
5236
         use return.  Inserting a jump 'by hand' is extremely messy, so
5237
         we take advantage of cfg_layout_finalize using
5238
        fixup_fallthru_exit_predecessor.  */
5239
      cfg_layout_initialize (0);
5240
      FOR_EACH_BB (cur_bb)
5241
        if (cur_bb->index >= NUM_FIXED_BLOCKS
5242
            && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5243
          cur_bb->aux = cur_bb->next_bb;
5244
      cfg_layout_finalize ();
5245
    }
5246
epilogue_done:
5247
  default_rtl_profile ();
5248
 
5249
  if (inserted)
5250
    {
5251
      commit_edge_insertions ();
5252
 
5253
      /* The epilogue insns we inserted may cause the exit edge to no longer
5254
         be fallthru.  */
5255
      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5256
        {
5257
          if (((e->flags & EDGE_FALLTHRU) != 0)
5258
              && returnjump_p (BB_END (e->src)))
5259
            e->flags &= ~EDGE_FALLTHRU;
5260
        }
5261
    }
5262
 
5263
#ifdef HAVE_sibcall_epilogue
5264
  /* Emit sibling epilogues before any sibling call sites.  */
5265
  for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5266
    {
5267
      basic_block bb = e->src;
5268
      rtx insn = BB_END (bb);
5269
 
5270
      if (!CALL_P (insn)
5271
          || ! SIBLING_CALL_P (insn))
5272
        {
5273
          ei_next (&ei);
5274
          continue;
5275
        }
5276
 
5277
      start_sequence ();
5278
      emit_note (NOTE_INSN_EPILOGUE_BEG);
5279
      emit_insn (gen_sibcall_epilogue ());
5280
      seq = get_insns ();
5281
      end_sequence ();
5282
 
5283
      /* Retain a map of the epilogue insns.  Used in life analysis to
5284
         avoid getting rid of sibcall epilogue insns.  Do this before we
5285
         actually emit the sequence.  */
5286
      record_insns (seq, NULL, &epilogue_insn_hash);
5287
      set_insn_locators (seq, epilogue_locator);
5288
 
5289
      emit_insn_before (seq, insn);
5290
      ei_next (&ei);
5291
    }
5292
#endif
5293
 
5294
#ifdef HAVE_epilogue
5295
  if (epilogue_end)
5296
    {
5297
      rtx insn, next;
5298
 
5299
      /* Similarly, move any line notes that appear after the epilogue.
5300
         There is no need, however, to be quite so anal about the existence
5301
         of such a note.  Also possibly move
5302
         NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5303
         info generation.  */
5304
      for (insn = epilogue_end; insn; insn = next)
5305
        {
5306
          next = NEXT_INSN (insn);
5307
          if (NOTE_P (insn)
5308
              && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5309
            reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5310
        }
5311
    }
5312
#endif
5313
 
5314
  /* Threading the prologue and epilogue changes the artificial refs
5315
     in the entry and exit blocks.  */
5316
  epilogue_completed = 1;
5317
  df_update_entry_exit_and_calls ();
5318
}
5319
 
5320
/* Reposition the prologue-end and epilogue-begin notes after
5321
   instruction scheduling.  */
5322
 
5323
void
5324
reposition_prologue_and_epilogue_notes (void)
5325
{
5326
#if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5327
    || defined (HAVE_sibcall_epilogue)
5328
  /* Since the hash table is created on demand, the fact that it is
5329
     non-null is a signal that it is non-empty.  */
5330
  if (prologue_insn_hash != NULL)
5331
    {
5332
      size_t len = htab_elements (prologue_insn_hash);
5333
      rtx insn, last = NULL, note = NULL;
5334
 
5335
      /* Scan from the beginning until we reach the last prologue insn.  */
5336
      /* ??? While we do have the CFG intact, there are two problems:
5337
         (1) The prologue can contain loops (typically probing the stack),
5338
             which means that the end of the prologue isn't in the first bb.
5339
         (2) Sometimes the PROLOGUE_END note gets pushed into the next bb.  */
5340
      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5341
        {
5342
          if (NOTE_P (insn))
5343
            {
5344
              if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5345
                note = insn;
5346
            }
5347
          else if (contains (insn, prologue_insn_hash))
5348
            {
5349
              last = insn;
5350
              if (--len == 0)
5351
                break;
5352
            }
5353
        }
5354
 
5355
      if (last)
5356
        {
5357
          if (note == NULL)
5358
            {
5359
              /* Scan forward looking for the PROLOGUE_END note.  It should
5360
                 be right at the beginning of the block, possibly with other
5361
                 insn notes that got moved there.  */
5362
              for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5363
                {
5364
                  if (NOTE_P (note)
5365
                      && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5366
                    break;
5367
                }
5368
            }
5369
 
5370
          /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note.  */
5371
          if (LABEL_P (last))
5372
            last = NEXT_INSN (last);
5373
          reorder_insns (note, note, last);
5374
        }
5375
    }
5376
 
5377
  if (epilogue_insn_hash != NULL)
5378
    {
5379
      edge_iterator ei;
5380
      edge e;
5381
 
5382
      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5383
        {
5384
          rtx insn, first = NULL, note = NULL;
5385
          basic_block bb = e->src;
5386
 
5387
          /* Scan from the beginning until we reach the first epilogue insn. */
5388
          FOR_BB_INSNS (bb, insn)
5389
            {
5390
              if (NOTE_P (insn))
5391
                {
5392
                  if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5393
                    {
5394
                      note = insn;
5395
                      if (first != NULL)
5396
                        break;
5397
                    }
5398
                }
5399
              else if (first == NULL && contains (insn, epilogue_insn_hash))
5400
                {
5401
                  first = insn;
5402
                  if (note != NULL)
5403
                    break;
5404
                }
5405
            }
5406
 
5407
          if (note)
5408
            {
5409
              /* If the function has a single basic block, and no real
5410
                 epilogue insns (e.g. sibcall with no cleanup), the
5411
                 epilogue note can get scheduled before the prologue
5412
                 note.  If we have frame related prologue insns, having
5413
                 them scanned during the epilogue will result in a crash.
5414
                 In this case re-order the epilogue note to just before
5415
                 the last insn in the block.  */
5416
              if (first == NULL)
5417
                first = BB_END (bb);
5418
 
5419
              if (PREV_INSN (first) != note)
5420
                reorder_insns (note, note, PREV_INSN (first));
5421
            }
5422
        }
5423
    }
5424
#endif /* HAVE_prologue or HAVE_epilogue */
5425
}
5426
 
5427
/* Returns the name of the current function.  */
5428
const char *
5429
current_function_name (void)
5430
{
5431
  if (cfun == NULL)
5432
    return "<none>";
5433
  return lang_hooks.decl_printable_name (cfun->decl, 2);
5434
}
5435
 
5436
 
5437
static unsigned int
5438
rest_of_handle_check_leaf_regs (void)
5439
{
5440
#ifdef LEAF_REGISTERS
5441
  current_function_uses_only_leaf_regs
5442
    = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5443
#endif
5444
  return 0;
5445
}
5446
 
5447
/* Insert a TYPE into the used types hash table of CFUN.  */
5448
 
5449
static void
5450
used_types_insert_helper (tree type, struct function *func)
5451
{
5452
  if (type != NULL && func != NULL)
5453
    {
5454
      void **slot;
5455
 
5456
      if (func->used_types_hash == NULL)
5457
        func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5458
                                                 htab_eq_pointer, NULL);
5459
      slot = htab_find_slot (func->used_types_hash, type, INSERT);
5460
      if (*slot == NULL)
5461
        *slot = type;
5462
    }
5463
}
5464
 
5465
/* Given a type, insert it into the used hash table in cfun.  */
5466
void
5467
used_types_insert (tree t)
5468
{
5469
  while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5470
    if (TYPE_NAME (t))
5471
      break;
5472
    else
5473
      t = TREE_TYPE (t);
5474
  if (TYPE_NAME (t) == NULL_TREE
5475
      || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
5476
    t = TYPE_MAIN_VARIANT (t);
5477
  if (debug_info_level > DINFO_LEVEL_NONE)
5478
    {
5479
      if (cfun)
5480
        used_types_insert_helper (t, cfun);
5481
      else
5482
        /* So this might be a type referenced by a global variable.
5483
           Record that type so that we can later decide to emit its debug
5484
           information.  */
5485
        types_used_by_cur_var_decl =
5486
          tree_cons (t, NULL, types_used_by_cur_var_decl);
5487
 
5488
    }
5489
}
5490
 
5491
/* Helper to Hash a struct types_used_by_vars_entry.  */
5492
 
5493
static hashval_t
5494
hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5495
{
5496
  gcc_assert (entry && entry->var_decl && entry->type);
5497
 
5498
  return iterative_hash_object (entry->type,
5499
                                iterative_hash_object (entry->var_decl, 0));
5500
}
5501
 
5502
/* Hash function of the types_used_by_vars_entry hash table.  */
5503
 
5504
hashval_t
5505
types_used_by_vars_do_hash (const void *x)
5506
{
5507
  const struct types_used_by_vars_entry *entry =
5508
    (const struct types_used_by_vars_entry *) x;
5509
 
5510
  return hash_types_used_by_vars_entry (entry);
5511
}
5512
 
5513
/*Equality function of the types_used_by_vars_entry hash table.  */
5514
 
5515
int
5516
types_used_by_vars_eq (const void *x1, const void *x2)
5517
{
5518
  const struct types_used_by_vars_entry *e1 =
5519
    (const struct types_used_by_vars_entry *) x1;
5520
  const struct types_used_by_vars_entry *e2 =
5521
    (const struct types_used_by_vars_entry *)x2;
5522
 
5523
  return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5524
}
5525
 
5526
/* Inserts an entry into the types_used_by_vars_hash hash table. */
5527
 
5528
void
5529
types_used_by_var_decl_insert (tree type, tree var_decl)
5530
{
5531
  if (type != NULL && var_decl != NULL)
5532
    {
5533
      void **slot;
5534
      struct types_used_by_vars_entry e;
5535
      e.var_decl = var_decl;
5536
      e.type = type;
5537
      if (types_used_by_vars_hash == NULL)
5538
        types_used_by_vars_hash =
5539
          htab_create_ggc (37, types_used_by_vars_do_hash,
5540
                           types_used_by_vars_eq, NULL);
5541
      slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5542
                                       hash_types_used_by_vars_entry (&e), INSERT);
5543
      if (*slot == NULL)
5544
        {
5545
          struct types_used_by_vars_entry *entry;
5546
          entry = (struct types_used_by_vars_entry*) ggc_alloc
5547
                    (sizeof (struct types_used_by_vars_entry));
5548
          entry->type = type;
5549
          entry->var_decl = var_decl;
5550
          *slot = entry;
5551
        }
5552
    }
5553
}
5554
 
5555
struct rtl_opt_pass pass_leaf_regs =
5556
{
5557
 {
5558
  RTL_PASS,
5559
  "*leaf_regs",                         /* name */
5560
  NULL,                                 /* gate */
5561
  rest_of_handle_check_leaf_regs,       /* execute */
5562
  NULL,                                 /* sub */
5563
  NULL,                                 /* next */
5564
  0,                                    /* static_pass_number */
5565
  TV_NONE,                              /* tv_id */
5566
  0,                                    /* properties_required */
5567
  0,                                    /* properties_provided */
5568
  0,                                    /* properties_destroyed */
5569
  0,                                    /* todo_flags_start */
5570
 
5571
 }
5572
};
5573
 
5574
static unsigned int
5575
rest_of_handle_thread_prologue_and_epilogue (void)
5576
{
5577
  if (optimize)
5578
    cleanup_cfg (CLEANUP_EXPENSIVE);
5579
  /* On some machines, the prologue and epilogue code, or parts thereof,
5580
     can be represented as RTL.  Doing so lets us schedule insns between
5581
     it and the rest of the code and also allows delayed branch
5582
     scheduling to operate in the epilogue.  */
5583
 
5584
  thread_prologue_and_epilogue_insns ();
5585
  return 0;
5586
}
5587
 
5588
struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5589
{
5590
 {
5591
  RTL_PASS,
5592
  "pro_and_epilogue",                   /* name */
5593
  NULL,                                 /* gate */
5594
  rest_of_handle_thread_prologue_and_epilogue, /* execute */
5595
  NULL,                                 /* sub */
5596
  NULL,                                 /* next */
5597
  0,                                    /* static_pass_number */
5598
  TV_THREAD_PROLOGUE_AND_EPILOGUE,      /* tv_id */
5599
  0,                                    /* properties_required */
5600
  0,                                    /* properties_provided */
5601
  0,                                    /* properties_destroyed */
5602
  TODO_verify_flow,                     /* todo_flags_start */
5603
  TODO_dump_func |
5604
  TODO_df_verify |
5605
  TODO_df_finish | TODO_verify_rtl_sharing |
5606
  TODO_ggc_collect                      /* todo_flags_finish */
5607
 }
5608
};
5609
 
5610
 
5611
/* This mini-pass fixes fall-out from SSA in asm statements that have
5612
   in-out constraints.  Say you start with
5613
 
5614
     orig = inout;
5615
     asm ("": "+mr" (inout));
5616
     use (orig);
5617
 
5618
   which is transformed very early to use explicit output and match operands:
5619
 
5620
     orig = inout;
5621
     asm ("": "=mr" (inout) : "0" (inout));
5622
     use (orig);
5623
 
5624
   Or, after SSA and copyprop,
5625
 
5626
     asm ("": "=mr" (inout_2) : "0" (inout_1));
5627
     use (inout_1);
5628
 
5629
   Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5630
   they represent two separate values, so they will get different pseudo
5631
   registers during expansion.  Then, since the two operands need to match
5632
   per the constraints, but use different pseudo registers, reload can
5633
   only register a reload for these operands.  But reloads can only be
5634
   satisfied by hardregs, not by memory, so we need a register for this
5635
   reload, just because we are presented with non-matching operands.
5636
   So, even though we allow memory for this operand, no memory can be
5637
   used for it, just because the two operands don't match.  This can
5638
   cause reload failures on register-starved targets.
5639
 
5640
   So it's a symptom of reload not being able to use memory for reloads
5641
   or, alternatively it's also a symptom of both operands not coming into
5642
   reload as matching (in which case the pseudo could go to memory just
5643
   fine, as the alternative allows it, and no reload would be necessary).
5644
   We fix the latter problem here, by transforming
5645
 
5646
     asm ("": "=mr" (inout_2) : "0" (inout_1));
5647
 
5648
   back to
5649
 
5650
     inout_2 = inout_1;
5651
     asm ("": "=mr" (inout_2) : "0" (inout_2));  */
5652
 
5653
static void
5654
match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5655
{
5656
  int i;
5657
  bool changed = false;
5658
  rtx op = SET_SRC (p_sets[0]);
5659
  int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5660
  rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5661
  bool *output_matched = XALLOCAVEC (bool, noutputs);
5662
 
5663
  memset (output_matched, 0, noutputs * sizeof (bool));
5664
  for (i = 0; i < ninputs; i++)
5665
    {
5666
      rtx input, output, insns;
5667
      const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5668
      char *end;
5669
      int match, j;
5670
 
5671
      if (*constraint == '%')
5672
        constraint++;
5673
 
5674
      match = strtoul (constraint, &end, 10);
5675
      if (end == constraint)
5676
        continue;
5677
 
5678
      gcc_assert (match < noutputs);
5679
      output = SET_DEST (p_sets[match]);
5680
      input = RTVEC_ELT (inputs, i);
5681
      /* Only do the transformation for pseudos.  */
5682
      if (! REG_P (output)
5683
          || rtx_equal_p (output, input)
5684
          || (GET_MODE (input) != VOIDmode
5685
              && GET_MODE (input) != GET_MODE (output)))
5686
        continue;
5687
 
5688
      /* We can't do anything if the output is also used as input,
5689
         as we're going to overwrite it.  */
5690
      for (j = 0; j < ninputs; j++)
5691
        if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5692
          break;
5693
      if (j != ninputs)
5694
        continue;
5695
 
5696
      /* Avoid changing the same input several times.  For
5697
         asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5698
         only change in once (to out1), rather than changing it
5699
         first to out1 and afterwards to out2.  */
5700
      if (i > 0)
5701
        {
5702
          for (j = 0; j < noutputs; j++)
5703
            if (output_matched[j] && input == SET_DEST (p_sets[j]))
5704
              break;
5705
          if (j != noutputs)
5706
            continue;
5707
        }
5708
      output_matched[match] = true;
5709
 
5710
      start_sequence ();
5711
      emit_move_insn (output, input);
5712
      insns = get_insns ();
5713
      end_sequence ();
5714
      emit_insn_before (insns, insn);
5715
 
5716
      /* Now replace all mentions of the input with output.  We can't
5717
         just replace the occurrence in inputs[i], as the register might
5718
         also be used in some other input (or even in an address of an
5719
         output), which would mean possibly increasing the number of
5720
         inputs by one (namely 'output' in addition), which might pose
5721
         a too complicated problem for reload to solve.  E.g. this situation:
5722
 
5723
           asm ("" : "=r" (output), "=m" (input) : "0" (input))
5724
 
5725
         Here 'input' is used in two occurrences as input (once for the
5726
         input operand, once for the address in the second output operand).
5727
         If we would replace only the occurrence of the input operand (to
5728
         make the matching) we would be left with this:
5729
 
5730
           output = input
5731
           asm ("" : "=r" (output), "=m" (input) : "0" (output))
5732
 
5733
         Now we suddenly have two different input values (containing the same
5734
         value, but different pseudos) where we formerly had only one.
5735
         With more complicated asms this might lead to reload failures
5736
         which wouldn't have happen without this pass.  So, iterate over
5737
         all operands and replace all occurrences of the register used.  */
5738
      for (j = 0; j < noutputs; j++)
5739
        if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5740
            && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5741
          SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5742
                                              input, output);
5743
      for (j = 0; j < ninputs; j++)
5744
        if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5745
          RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5746
                                               input, output);
5747
 
5748
      changed = true;
5749
    }
5750
 
5751
  if (changed)
5752
    df_insn_rescan (insn);
5753
}
5754
 
5755
static unsigned
5756
rest_of_match_asm_constraints (void)
5757
{
5758
  basic_block bb;
5759
  rtx insn, pat, *p_sets;
5760
  int noutputs;
5761
 
5762
  if (!crtl->has_asm_statement)
5763
    return 0;
5764
 
5765
  df_set_flags (DF_DEFER_INSN_RESCAN);
5766
  FOR_EACH_BB (bb)
5767
    {
5768
      FOR_BB_INSNS (bb, insn)
5769
        {
5770
          if (!INSN_P (insn))
5771
            continue;
5772
 
5773
          pat = PATTERN (insn);
5774
          if (GET_CODE (pat) == PARALLEL)
5775
            p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5776
          else if (GET_CODE (pat) == SET)
5777
            p_sets = &PATTERN (insn), noutputs = 1;
5778
          else
5779
            continue;
5780
 
5781
          if (GET_CODE (*p_sets) == SET
5782
              && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5783
            match_asm_constraints_1 (insn, p_sets, noutputs);
5784
         }
5785
    }
5786
 
5787
  return TODO_df_finish;
5788
}
5789
 
5790
struct rtl_opt_pass pass_match_asm_constraints =
5791
{
5792
 {
5793
  RTL_PASS,
5794
  "asmcons",                            /* name */
5795
  NULL,                                 /* gate */
5796
  rest_of_match_asm_constraints,        /* execute */
5797
  NULL,                                 /* sub */
5798
  NULL,                                 /* next */
5799
  0,                                    /* static_pass_number */
5800
  TV_NONE,                              /* tv_id */
5801
  0,                                    /* properties_required */
5802
  0,                                    /* properties_provided */
5803
  0,                                    /* properties_destroyed */
5804
  0,                                     /* todo_flags_start */
5805
  TODO_dump_func                       /* todo_flags_finish */
5806
 }
5807
};
5808
 
5809
 
5810
#include "gt-function.h"

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