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[/] [openrisc/] [trunk/] [gnu-src/] [gcc-4.5.1/] [gcc/] [function.c] - Blame information for rev 280

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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
                     not the PARMs.  */
3427
                  if (TREE_ADDRESSABLE (parm))
3428
                    {
3429
                      TREE_ADDRESSABLE (parm) = 0;
3430
                      TREE_ADDRESSABLE (local) = 1;
3431
                    }
3432
                }
3433
              else
3434
                {
3435
                  tree ptr_type, addr;
3436
 
3437
                  ptr_type = build_pointer_type (type);
3438
                  addr = create_tmp_var (ptr_type, get_name (parm));
3439
                  DECL_IGNORED_P (addr) = 0;
3440
                  local = build_fold_indirect_ref (addr);
3441
 
3442
                  t = built_in_decls[BUILT_IN_ALLOCA];
3443
                  t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3444
                  t = fold_convert (ptr_type, t);
3445
                  t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3446
                  gimplify_and_add (t, &stmts);
3447
                }
3448
 
3449
              gimplify_assign (local, parm, &stmts);
3450
 
3451
              SET_DECL_VALUE_EXPR (parm, local);
3452
              DECL_HAS_VALUE_EXPR_P (parm) = 1;
3453
            }
3454
        }
3455
    }
3456
 
3457
  VEC_free (tree, heap, fnargs);
3458
 
3459
  return stmts;
3460
}
3461
 
3462
/* Compute the size and offset from the start of the stacked arguments for a
3463
   parm passed in mode PASSED_MODE and with type TYPE.
3464
 
3465
   INITIAL_OFFSET_PTR points to the current offset into the stacked
3466
   arguments.
3467
 
3468
   The starting offset and size for this parm are returned in
3469
   LOCATE->OFFSET and LOCATE->SIZE, respectively.  When IN_REGS is
3470
   nonzero, the offset is that of stack slot, which is returned in
3471
   LOCATE->SLOT_OFFSET.  LOCATE->ALIGNMENT_PAD is the amount of
3472
   padding required from the initial offset ptr to the stack slot.
3473
 
3474
   IN_REGS is nonzero if the argument will be passed in registers.  It will
3475
   never be set if REG_PARM_STACK_SPACE is not defined.
3476
 
3477
   FNDECL is the function in which the argument was defined.
3478
 
3479
   There are two types of rounding that are done.  The first, controlled by
3480
   FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3481
   list to be aligned to the specific boundary (in bits).  This rounding
3482
   affects the initial and starting offsets, but not the argument size.
3483
 
3484
   The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3485
   optionally rounds the size of the parm to PARM_BOUNDARY.  The
3486
   initial offset is not affected by this rounding, while the size always
3487
   is and the starting offset may be.  */
3488
 
3489
/*  LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3490
    INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3491
    callers pass in the total size of args so far as
3492
    INITIAL_OFFSET_PTR.  LOCATE->SIZE is always positive.  */
3493
 
3494
void
3495
locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3496
                     int partial, tree fndecl ATTRIBUTE_UNUSED,
3497
                     struct args_size *initial_offset_ptr,
3498
                     struct locate_and_pad_arg_data *locate)
3499
{
3500
  tree sizetree;
3501
  enum direction where_pad;
3502
  unsigned int boundary;
3503
  int reg_parm_stack_space = 0;
3504
  int part_size_in_regs;
3505
 
3506
#ifdef REG_PARM_STACK_SPACE
3507
  reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3508
 
3509
  /* If we have found a stack parm before we reach the end of the
3510
     area reserved for registers, skip that area.  */
3511
  if (! in_regs)
3512
    {
3513
      if (reg_parm_stack_space > 0)
3514
        {
3515
          if (initial_offset_ptr->var)
3516
            {
3517
              initial_offset_ptr->var
3518
                = size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3519
                              ssize_int (reg_parm_stack_space));
3520
              initial_offset_ptr->constant = 0;
3521
            }
3522
          else if (initial_offset_ptr->constant < reg_parm_stack_space)
3523
            initial_offset_ptr->constant = reg_parm_stack_space;
3524
        }
3525
    }
3526
#endif /* REG_PARM_STACK_SPACE */
3527
 
3528
  part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3529
 
3530
  sizetree
3531
    = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3532
  where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3533
  boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3534
  locate->where_pad = where_pad;
3535
 
3536
  /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT.  */
3537
  if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3538
    boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3539
 
3540
  locate->boundary = boundary;
3541
 
3542
  if (SUPPORTS_STACK_ALIGNMENT)
3543
    {
3544
      /* stack_alignment_estimated can't change after stack has been
3545
         realigned.  */
3546
      if (crtl->stack_alignment_estimated < boundary)
3547
        {
3548
          if (!crtl->stack_realign_processed)
3549
            crtl->stack_alignment_estimated = boundary;
3550
          else
3551
            {
3552
              /* If stack is realigned and stack alignment value
3553
                 hasn't been finalized, it is OK not to increase
3554
                 stack_alignment_estimated.  The bigger alignment
3555
                 requirement is recorded in stack_alignment_needed
3556
                 below.  */
3557
              gcc_assert (!crtl->stack_realign_finalized
3558
                          && crtl->stack_realign_needed);
3559
            }
3560
        }
3561
    }
3562
 
3563
  /* Remember if the outgoing parameter requires extra alignment on the
3564
     calling function side.  */
3565
  if (crtl->stack_alignment_needed < boundary)
3566
    crtl->stack_alignment_needed = boundary;
3567
  if (crtl->preferred_stack_boundary < boundary)
3568
    crtl->preferred_stack_boundary = boundary;
3569
 
3570
#ifdef ARGS_GROW_DOWNWARD
3571
  locate->slot_offset.constant = -initial_offset_ptr->constant;
3572
  if (initial_offset_ptr->var)
3573
    locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3574
                                          initial_offset_ptr->var);
3575
 
3576
  {
3577
    tree s2 = sizetree;
3578
    if (where_pad != none
3579
        && (!host_integerp (sizetree, 1)
3580
            || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3581
      s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3582
    SUB_PARM_SIZE (locate->slot_offset, s2);
3583
  }
3584
 
3585
  locate->slot_offset.constant += part_size_in_regs;
3586
 
3587
  if (!in_regs
3588
#ifdef REG_PARM_STACK_SPACE
3589
      || REG_PARM_STACK_SPACE (fndecl) > 0
3590
#endif
3591
     )
3592
    pad_to_arg_alignment (&locate->slot_offset, boundary,
3593
                          &locate->alignment_pad);
3594
 
3595
  locate->size.constant = (-initial_offset_ptr->constant
3596
                           - locate->slot_offset.constant);
3597
  if (initial_offset_ptr->var)
3598
    locate->size.var = size_binop (MINUS_EXPR,
3599
                                   size_binop (MINUS_EXPR,
3600
                                               ssize_int (0),
3601
                                               initial_offset_ptr->var),
3602
                                   locate->slot_offset.var);
3603
 
3604
  /* Pad_below needs the pre-rounded size to know how much to pad
3605
     below.  */
3606
  locate->offset = locate->slot_offset;
3607
  if (where_pad == downward)
3608
    pad_below (&locate->offset, passed_mode, sizetree);
3609
 
3610
#else /* !ARGS_GROW_DOWNWARD */
3611
  if (!in_regs
3612
#ifdef REG_PARM_STACK_SPACE
3613
      || REG_PARM_STACK_SPACE (fndecl) > 0
3614
#endif
3615
      )
3616
    pad_to_arg_alignment (initial_offset_ptr, boundary,
3617
                          &locate->alignment_pad);
3618
  locate->slot_offset = *initial_offset_ptr;
3619
 
3620
#ifdef PUSH_ROUNDING
3621
  if (passed_mode != BLKmode)
3622
    sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3623
#endif
3624
 
3625
  /* Pad_below needs the pre-rounded size to know how much to pad below
3626
     so this must be done before rounding up.  */
3627
  locate->offset = locate->slot_offset;
3628
  if (where_pad == downward)
3629
    pad_below (&locate->offset, passed_mode, sizetree);
3630
 
3631
  if (where_pad != none
3632
      && (!host_integerp (sizetree, 1)
3633
          || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3634
    sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3635
 
3636
  ADD_PARM_SIZE (locate->size, sizetree);
3637
 
3638
  locate->size.constant -= part_size_in_regs;
3639
#endif /* ARGS_GROW_DOWNWARD */
3640
 
3641
#ifdef FUNCTION_ARG_OFFSET
3642
  locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3643
#endif
3644
}
3645
 
3646
/* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3647
   BOUNDARY is measured in bits, but must be a multiple of a storage unit.  */
3648
 
3649
static void
3650
pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3651
                      struct args_size *alignment_pad)
3652
{
3653
  tree save_var = NULL_TREE;
3654
  HOST_WIDE_INT save_constant = 0;
3655
  int boundary_in_bytes = boundary / BITS_PER_UNIT;
3656
  HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3657
 
3658
#ifdef SPARC_STACK_BOUNDARY_HACK
3659
  /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3660
     the real alignment of %sp.  However, when it does this, the
3661
     alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY.  */
3662
  if (SPARC_STACK_BOUNDARY_HACK)
3663
    sp_offset = 0;
3664
#endif
3665
 
3666
  if (boundary > PARM_BOUNDARY)
3667
    {
3668
      save_var = offset_ptr->var;
3669
      save_constant = offset_ptr->constant;
3670
    }
3671
 
3672
  alignment_pad->var = NULL_TREE;
3673
  alignment_pad->constant = 0;
3674
 
3675
  if (boundary > BITS_PER_UNIT)
3676
    {
3677
      if (offset_ptr->var)
3678
        {
3679
          tree sp_offset_tree = ssize_int (sp_offset);
3680
          tree offset = size_binop (PLUS_EXPR,
3681
                                    ARGS_SIZE_TREE (*offset_ptr),
3682
                                    sp_offset_tree);
3683
#ifdef ARGS_GROW_DOWNWARD
3684
          tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3685
#else
3686
          tree rounded = round_up   (offset, boundary / BITS_PER_UNIT);
3687
#endif
3688
 
3689
          offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3690
          /* ARGS_SIZE_TREE includes constant term.  */
3691
          offset_ptr->constant = 0;
3692
          if (boundary > PARM_BOUNDARY)
3693
            alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3694
                                             save_var);
3695
        }
3696
      else
3697
        {
3698
          offset_ptr->constant = -sp_offset +
3699
#ifdef ARGS_GROW_DOWNWARD
3700
            FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3701
#else
3702
            CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3703
#endif
3704
            if (boundary > PARM_BOUNDARY)
3705
              alignment_pad->constant = offset_ptr->constant - save_constant;
3706
        }
3707
    }
3708
}
3709
 
3710
static void
3711
pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3712
{
3713
  if (passed_mode != BLKmode)
3714
    {
3715
      if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3716
        offset_ptr->constant
3717
          += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3718
               / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3719
              - GET_MODE_SIZE (passed_mode));
3720
    }
3721
  else
3722
    {
3723
      if (TREE_CODE (sizetree) != INTEGER_CST
3724
          || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3725
        {
3726
          /* Round the size up to multiple of PARM_BOUNDARY bits.  */
3727
          tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3728
          /* Add it in.  */
3729
          ADD_PARM_SIZE (*offset_ptr, s2);
3730
          SUB_PARM_SIZE (*offset_ptr, sizetree);
3731
        }
3732
    }
3733
}
3734
 
3735
 
3736
/* True if register REGNO was alive at a place where `setjmp' was
3737
   called and was set more than once or is an argument.  Such regs may
3738
   be clobbered by `longjmp'.  */
3739
 
3740
static bool
3741
regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3742
{
3743
  /* There appear to be cases where some local vars never reach the
3744
     backend but have bogus regnos.  */
3745
  if (regno >= max_reg_num ())
3746
    return false;
3747
 
3748
  return ((REG_N_SETS (regno) > 1
3749
           || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3750
          && REGNO_REG_SET_P (setjmp_crosses, regno));
3751
}
3752
 
3753
/* Walk the tree of blocks describing the binding levels within a
3754
   function and warn about variables the might be killed by setjmp or
3755
   vfork.  This is done after calling flow_analysis before register
3756
   allocation since that will clobber the pseudo-regs to hard
3757
   regs.  */
3758
 
3759
static void
3760
setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3761
{
3762
  tree decl, sub;
3763
 
3764
  for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3765
    {
3766
      if (TREE_CODE (decl) == VAR_DECL
3767
          && DECL_RTL_SET_P (decl)
3768
          && REG_P (DECL_RTL (decl))
3769
          && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3770
        warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3771
                 " %<longjmp%> or %<vfork%>", decl);
3772
    }
3773
 
3774
  for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3775
    setjmp_vars_warning (setjmp_crosses, sub);
3776
}
3777
 
3778
/* Do the appropriate part of setjmp_vars_warning
3779
   but for arguments instead of local variables.  */
3780
 
3781
static void
3782
setjmp_args_warning (bitmap setjmp_crosses)
3783
{
3784
  tree decl;
3785
  for (decl = DECL_ARGUMENTS (current_function_decl);
3786
       decl; decl = TREE_CHAIN (decl))
3787
    if (DECL_RTL (decl) != 0
3788
        && REG_P (DECL_RTL (decl))
3789
        && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3790
      warning (OPT_Wclobbered,
3791
               "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3792
               decl);
3793
}
3794
 
3795
/* Generate warning messages for variables live across setjmp.  */
3796
 
3797
void
3798
generate_setjmp_warnings (void)
3799
{
3800
  bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3801
 
3802
  if (n_basic_blocks == NUM_FIXED_BLOCKS
3803
      || bitmap_empty_p (setjmp_crosses))
3804
    return;
3805
 
3806
  setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3807
  setjmp_args_warning (setjmp_crosses);
3808
}
3809
 
3810
 
3811
/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3812
   and create duplicate blocks.  */
3813
/* ??? Need an option to either create block fragments or to create
3814
   abstract origin duplicates of a source block.  It really depends
3815
   on what optimization has been performed.  */
3816
 
3817
void
3818
reorder_blocks (void)
3819
{
3820
  tree block = DECL_INITIAL (current_function_decl);
3821
  VEC(tree,heap) *block_stack;
3822
 
3823
  if (block == NULL_TREE)
3824
    return;
3825
 
3826
  block_stack = VEC_alloc (tree, heap, 10);
3827
 
3828
  /* Reset the TREE_ASM_WRITTEN bit for all blocks.  */
3829
  clear_block_marks (block);
3830
 
3831
  /* Prune the old trees away, so that they don't get in the way.  */
3832
  BLOCK_SUBBLOCKS (block) = NULL_TREE;
3833
  BLOCK_CHAIN (block) = NULL_TREE;
3834
 
3835
  /* Recreate the block tree from the note nesting.  */
3836
  reorder_blocks_1 (get_insns (), block, &block_stack);
3837
  BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3838
 
3839
  VEC_free (tree, heap, block_stack);
3840
}
3841
 
3842
/* Helper function for reorder_blocks.  Reset TREE_ASM_WRITTEN.  */
3843
 
3844
void
3845
clear_block_marks (tree block)
3846
{
3847
  while (block)
3848
    {
3849
      TREE_ASM_WRITTEN (block) = 0;
3850
      clear_block_marks (BLOCK_SUBBLOCKS (block));
3851
      block = BLOCK_CHAIN (block);
3852
    }
3853
}
3854
 
3855
static void
3856
reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3857
{
3858
  rtx insn;
3859
 
3860
  for (insn = insns; insn; insn = NEXT_INSN (insn))
3861
    {
3862
      if (NOTE_P (insn))
3863
        {
3864
          if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
3865
            {
3866
              tree block = NOTE_BLOCK (insn);
3867
              tree origin;
3868
 
3869
              origin = (BLOCK_FRAGMENT_ORIGIN (block)
3870
                        ? BLOCK_FRAGMENT_ORIGIN (block)
3871
                        : block);
3872
 
3873
              /* If we have seen this block before, that means it now
3874
                 spans multiple address regions.  Create a new fragment.  */
3875
              if (TREE_ASM_WRITTEN (block))
3876
                {
3877
                  tree new_block = copy_node (block);
3878
 
3879
                  BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3880
                  BLOCK_FRAGMENT_CHAIN (new_block)
3881
                    = BLOCK_FRAGMENT_CHAIN (origin);
3882
                  BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3883
 
3884
                  NOTE_BLOCK (insn) = new_block;
3885
                  block = new_block;
3886
                }
3887
 
3888
              BLOCK_SUBBLOCKS (block) = 0;
3889
              TREE_ASM_WRITTEN (block) = 1;
3890
              /* When there's only one block for the entire function,
3891
                 current_block == block and we mustn't do this, it
3892
                 will cause infinite recursion.  */
3893
              if (block != current_block)
3894
                {
3895
                  if (block != origin)
3896
                    gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
3897
 
3898
                  BLOCK_SUPERCONTEXT (block) = current_block;
3899
                  BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3900
                  BLOCK_SUBBLOCKS (current_block) = block;
3901
                  current_block = origin;
3902
                }
3903
              VEC_safe_push (tree, heap, *p_block_stack, block);
3904
            }
3905
          else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
3906
            {
3907
              NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3908
              BLOCK_SUBBLOCKS (current_block)
3909
                = blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3910
              current_block = BLOCK_SUPERCONTEXT (current_block);
3911
            }
3912
        }
3913
    }
3914
}
3915
 
3916
/* Reverse the order of elements in the chain T of blocks,
3917
   and return the new head of the chain (old last element).  */
3918
 
3919
tree
3920
blocks_nreverse (tree t)
3921
{
3922
  tree prev = 0, decl, next;
3923
  for (decl = t; decl; decl = next)
3924
    {
3925
      next = BLOCK_CHAIN (decl);
3926
      BLOCK_CHAIN (decl) = prev;
3927
      prev = decl;
3928
    }
3929
  return prev;
3930
}
3931
 
3932
/* Count the subblocks of the list starting with BLOCK.  If VECTOR is
3933
   non-NULL, list them all into VECTOR, in a depth-first preorder
3934
   traversal of the block tree.  Also clear TREE_ASM_WRITTEN in all
3935
   blocks.  */
3936
 
3937
static int
3938
all_blocks (tree block, tree *vector)
3939
{
3940
  int n_blocks = 0;
3941
 
3942
  while (block)
3943
    {
3944
      TREE_ASM_WRITTEN (block) = 0;
3945
 
3946
      /* Record this block.  */
3947
      if (vector)
3948
        vector[n_blocks] = block;
3949
 
3950
      ++n_blocks;
3951
 
3952
      /* Record the subblocks, and their subblocks...  */
3953
      n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3954
                              vector ? vector + n_blocks : 0);
3955
      block = BLOCK_CHAIN (block);
3956
    }
3957
 
3958
  return n_blocks;
3959
}
3960
 
3961
/* Return a vector containing all the blocks rooted at BLOCK.  The
3962
   number of elements in the vector is stored in N_BLOCKS_P.  The
3963
   vector is dynamically allocated; it is the caller's responsibility
3964
   to call `free' on the pointer returned.  */
3965
 
3966
static tree *
3967
get_block_vector (tree block, int *n_blocks_p)
3968
{
3969
  tree *block_vector;
3970
 
3971
  *n_blocks_p = all_blocks (block, NULL);
3972
  block_vector = XNEWVEC (tree, *n_blocks_p);
3973
  all_blocks (block, block_vector);
3974
 
3975
  return block_vector;
3976
}
3977
 
3978
static GTY(()) int next_block_index = 2;
3979
 
3980
/* Set BLOCK_NUMBER for all the blocks in FN.  */
3981
 
3982
void
3983
number_blocks (tree fn)
3984
{
3985
  int i;
3986
  int n_blocks;
3987
  tree *block_vector;
3988
 
3989
  /* For SDB and XCOFF debugging output, we start numbering the blocks
3990
     from 1 within each function, rather than keeping a running
3991
     count.  */
3992
#if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3993
  if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3994
    next_block_index = 1;
3995
#endif
3996
 
3997
  block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3998
 
3999
  /* The top-level BLOCK isn't numbered at all.  */
4000
  for (i = 1; i < n_blocks; ++i)
4001
    /* We number the blocks from two.  */
4002
    BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4003
 
4004
  free (block_vector);
4005
 
4006
  return;
4007
}
4008
 
4009
/* If VAR is present in a subblock of BLOCK, return the subblock.  */
4010
 
4011
tree
4012
debug_find_var_in_block_tree (tree var, tree block)
4013
{
4014
  tree t;
4015
 
4016
  for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4017
    if (t == var)
4018
      return block;
4019
 
4020
  for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4021
    {
4022
      tree ret = debug_find_var_in_block_tree (var, t);
4023
      if (ret)
4024
        return ret;
4025
    }
4026
 
4027
  return NULL_TREE;
4028
}
4029
 
4030
/* Keep track of whether we're in a dummy function context.  If we are,
4031
   we don't want to invoke the set_current_function hook, because we'll
4032
   get into trouble if the hook calls target_reinit () recursively or
4033
   when the initial initialization is not yet complete.  */
4034
 
4035
static bool in_dummy_function;
4036
 
4037
/* Invoke the target hook when setting cfun.  Update the optimization options
4038
   if the function uses different options than the default.  */
4039
 
4040
static void
4041
invoke_set_current_function_hook (tree fndecl)
4042
{
4043
  if (!in_dummy_function)
4044
    {
4045
      tree opts = ((fndecl)
4046
                   ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4047
                   : optimization_default_node);
4048
 
4049
      if (!opts)
4050
        opts = optimization_default_node;
4051
 
4052
      /* Change optimization options if needed.  */
4053
      if (optimization_current_node != opts)
4054
        {
4055
          optimization_current_node = opts;
4056
          cl_optimization_restore (TREE_OPTIMIZATION (opts));
4057
        }
4058
 
4059
      targetm.set_current_function (fndecl);
4060
    }
4061
}
4062
 
4063
/* cfun should never be set directly; use this function.  */
4064
 
4065
void
4066
set_cfun (struct function *new_cfun)
4067
{
4068
  if (cfun != new_cfun)
4069
    {
4070
      cfun = new_cfun;
4071
      invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4072
    }
4073
}
4074
 
4075
/* Initialized with NOGC, making this poisonous to the garbage collector.  */
4076
 
4077
static VEC(function_p,heap) *cfun_stack;
4078
 
4079
/* Push the current cfun onto the stack, and set cfun to new_cfun.  */
4080
 
4081
void
4082
push_cfun (struct function *new_cfun)
4083
{
4084
  VEC_safe_push (function_p, heap, cfun_stack, cfun);
4085
  set_cfun (new_cfun);
4086
}
4087
 
4088
/* Pop cfun from the stack.  */
4089
 
4090
void
4091
pop_cfun (void)
4092
{
4093
  struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4094
  set_cfun (new_cfun);
4095
}
4096
 
4097
/* Return value of funcdef and increase it.  */
4098
int
4099
get_next_funcdef_no (void)
4100
{
4101
  return funcdef_no++;
4102
}
4103
 
4104
/* Allocate a function structure for FNDECL and set its contents
4105
   to the defaults.  Set cfun to the newly-allocated object.
4106
   Some of the helper functions invoked during initialization assume
4107
   that cfun has already been set.  Therefore, assign the new object
4108
   directly into cfun and invoke the back end hook explicitly at the
4109
   very end, rather than initializing a temporary and calling set_cfun
4110
   on it.
4111
 
4112
   ABSTRACT_P is true if this is a function that will never be seen by
4113
   the middle-end.  Such functions are front-end concepts (like C++
4114
   function templates) that do not correspond directly to functions
4115
   placed in object files.  */
4116
 
4117
void
4118
allocate_struct_function (tree fndecl, bool abstract_p)
4119
{
4120
  tree result;
4121
  tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4122
 
4123
  cfun = GGC_CNEW (struct function);
4124
 
4125
  cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
4126
 
4127
  init_eh_for_function ();
4128
 
4129
  if (init_machine_status)
4130
    cfun->machine = (*init_machine_status) ();
4131
 
4132
#ifdef OVERRIDE_ABI_FORMAT
4133
  OVERRIDE_ABI_FORMAT (fndecl);
4134
#endif
4135
 
4136
  invoke_set_current_function_hook (fndecl);
4137
 
4138
  if (fndecl != NULL_TREE)
4139
    {
4140
      DECL_STRUCT_FUNCTION (fndecl) = cfun;
4141
      cfun->decl = fndecl;
4142
      current_function_funcdef_no = get_next_funcdef_no ();
4143
 
4144
      result = DECL_RESULT (fndecl);
4145
      if (!abstract_p && aggregate_value_p (result, fndecl))
4146
        {
4147
#ifdef PCC_STATIC_STRUCT_RETURN
4148
          cfun->returns_pcc_struct = 1;
4149
#endif
4150
          cfun->returns_struct = 1;
4151
        }
4152
 
4153
      cfun->stdarg
4154
        = (fntype
4155
           && TYPE_ARG_TYPES (fntype) != 0
4156
           && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4157
               != void_type_node));
4158
 
4159
      /* Assume all registers in stdarg functions need to be saved.  */
4160
      cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4161
      cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4162
    }
4163
}
4164
 
4165
/* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4166
   instead of just setting it.  */
4167
 
4168
void
4169
push_struct_function (tree fndecl)
4170
{
4171
  VEC_safe_push (function_p, heap, cfun_stack, cfun);
4172
  allocate_struct_function (fndecl, false);
4173
}
4174
 
4175
/* Reset cfun, and other non-struct-function variables to defaults as
4176
   appropriate for emitting rtl at the start of a function.  */
4177
 
4178
static void
4179
prepare_function_start (void)
4180
{
4181
  gcc_assert (!crtl->emit.x_last_insn);
4182
  init_temp_slots ();
4183
  init_emit ();
4184
  init_varasm_status ();
4185
  init_expr ();
4186
  default_rtl_profile ();
4187
 
4188
  cse_not_expected = ! optimize;
4189
 
4190
  /* Caller save not needed yet.  */
4191
  caller_save_needed = 0;
4192
 
4193
  /* We haven't done register allocation yet.  */
4194
  reg_renumber = 0;
4195
 
4196
  /* Indicate that we have not instantiated virtual registers yet.  */
4197
  virtuals_instantiated = 0;
4198
 
4199
  /* Indicate that we want CONCATs now.  */
4200
  generating_concat_p = 1;
4201
 
4202
  /* Indicate we have no need of a frame pointer yet.  */
4203
  frame_pointer_needed = 0;
4204
}
4205
 
4206
/* Initialize the rtl expansion mechanism so that we can do simple things
4207
   like generate sequences.  This is used to provide a context during global
4208
   initialization of some passes.  You must call expand_dummy_function_end
4209
   to exit this context.  */
4210
 
4211
void
4212
init_dummy_function_start (void)
4213
{
4214
  gcc_assert (!in_dummy_function);
4215
  in_dummy_function = true;
4216
  push_struct_function (NULL_TREE);
4217
  prepare_function_start ();
4218
}
4219
 
4220
/* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4221
   and initialize static variables for generating RTL for the statements
4222
   of the function.  */
4223
 
4224
void
4225
init_function_start (tree subr)
4226
{
4227
  if (subr && DECL_STRUCT_FUNCTION (subr))
4228
    set_cfun (DECL_STRUCT_FUNCTION (subr));
4229
  else
4230
    allocate_struct_function (subr, false);
4231
  prepare_function_start ();
4232
 
4233
  /* Warn if this value is an aggregate type,
4234
     regardless of which calling convention we are using for it.  */
4235
  if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4236
    warning (OPT_Waggregate_return, "function returns an aggregate");
4237
}
4238
 
4239
/* Make sure all values used by the optimization passes have sane defaults.  */
4240
unsigned int
4241
init_function_for_compilation (void)
4242
{
4243
  reg_renumber = 0;
4244
  return 0;
4245
}
4246
 
4247
struct rtl_opt_pass pass_init_function =
4248
{
4249
 {
4250
  RTL_PASS,
4251
  "*init_function",                     /* name */
4252
  NULL,                                 /* gate */
4253
  init_function_for_compilation,        /* execute */
4254
  NULL,                                 /* sub */
4255
  NULL,                                 /* next */
4256
  0,                                    /* static_pass_number */
4257
  TV_NONE,                              /* tv_id */
4258
  0,                                    /* properties_required */
4259
  0,                                    /* properties_provided */
4260
  0,                                    /* properties_destroyed */
4261
  0,                                    /* todo_flags_start */
4262
 
4263
 }
4264
};
4265
 
4266
 
4267
void
4268
expand_main_function (void)
4269
{
4270
#if (defined(INVOKE__main)                              \
4271
     || (!defined(HAS_INIT_SECTION)                     \
4272
         && !defined(INIT_SECTION_ASM_OP)               \
4273
         && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4274
  emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4275
#endif
4276
}
4277
 
4278
/* Expand code to initialize the stack_protect_guard.  This is invoked at
4279
   the beginning of a function to be protected.  */
4280
 
4281
#ifndef HAVE_stack_protect_set
4282
# define HAVE_stack_protect_set         0
4283
# define gen_stack_protect_set(x,y)     (gcc_unreachable (), NULL_RTX)
4284
#endif
4285
 
4286
void
4287
stack_protect_prologue (void)
4288
{
4289
  tree guard_decl = targetm.stack_protect_guard ();
4290
  rtx x, y;
4291
 
4292
  x = expand_normal (crtl->stack_protect_guard);
4293
  y = expand_normal (guard_decl);
4294
 
4295
  /* Allow the target to copy from Y to X without leaking Y into a
4296
     register.  */
4297
  if (HAVE_stack_protect_set)
4298
    {
4299
      rtx insn = gen_stack_protect_set (x, y);
4300
      if (insn)
4301
        {
4302
          emit_insn (insn);
4303
          return;
4304
        }
4305
    }
4306
 
4307
  /* Otherwise do a straight move.  */
4308
  emit_move_insn (x, y);
4309
}
4310
 
4311
/* Expand code to verify the stack_protect_guard.  This is invoked at
4312
   the end of a function to be protected.  */
4313
 
4314
#ifndef HAVE_stack_protect_test
4315
# define HAVE_stack_protect_test                0
4316
# define gen_stack_protect_test(x, y, z)        (gcc_unreachable (), NULL_RTX)
4317
#endif
4318
 
4319
void
4320
stack_protect_epilogue (void)
4321
{
4322
  tree guard_decl = targetm.stack_protect_guard ();
4323
  rtx label = gen_label_rtx ();
4324
  rtx x, y, tmp;
4325
 
4326
  x = expand_normal (crtl->stack_protect_guard);
4327
  y = expand_normal (guard_decl);
4328
 
4329
  /* Allow the target to compare Y with X without leaking either into
4330
     a register.  */
4331
  switch (HAVE_stack_protect_test != 0)
4332
    {
4333
    case 1:
4334
      tmp = gen_stack_protect_test (x, y, label);
4335
      if (tmp)
4336
        {
4337
          emit_insn (tmp);
4338
          break;
4339
        }
4340
      /* FALLTHRU */
4341
 
4342
    default:
4343
      emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4344
      break;
4345
    }
4346
 
4347
  /* The noreturn predictor has been moved to the tree level.  The rtl-level
4348
     predictors estimate this branch about 20%, which isn't enough to get
4349
     things moved out of line.  Since this is the only extant case of adding
4350
     a noreturn function at the rtl level, it doesn't seem worth doing ought
4351
     except adding the prediction by hand.  */
4352
  tmp = get_last_insn ();
4353
  if (JUMP_P (tmp))
4354
    predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4355
 
4356
  expand_expr_stmt (targetm.stack_protect_fail ());
4357
  emit_label (label);
4358
}
4359
 
4360
/* Start the RTL for a new function, and set variables used for
4361
   emitting RTL.
4362
   SUBR is the FUNCTION_DECL node.
4363
   PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4364
   the function's parameters, which must be run at any return statement.  */
4365
 
4366
void
4367
expand_function_start (tree subr)
4368
{
4369
  /* Make sure volatile mem refs aren't considered
4370
     valid operands of arithmetic insns.  */
4371
  init_recog_no_volatile ();
4372
 
4373
  crtl->profile
4374
    = (profile_flag
4375
       && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4376
 
4377
  crtl->limit_stack
4378
    = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4379
 
4380
  /* Make the label for return statements to jump to.  Do not special
4381
     case machines with special return instructions -- they will be
4382
     handled later during jump, ifcvt, or epilogue creation.  */
4383
  return_label = gen_label_rtx ();
4384
 
4385
  /* Initialize rtx used to return the value.  */
4386
  /* Do this before assign_parms so that we copy the struct value address
4387
     before any library calls that assign parms might generate.  */
4388
 
4389
  /* Decide whether to return the value in memory or in a register.  */
4390
  if (aggregate_value_p (DECL_RESULT (subr), subr))
4391
    {
4392
      /* Returning something that won't go in a register.  */
4393
      rtx value_address = 0;
4394
 
4395
#ifdef PCC_STATIC_STRUCT_RETURN
4396
      if (cfun->returns_pcc_struct)
4397
        {
4398
          int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4399
          value_address = assemble_static_space (size);
4400
        }
4401
      else
4402
#endif
4403
        {
4404
          rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4405
          /* Expect to be passed the address of a place to store the value.
4406
             If it is passed as an argument, assign_parms will take care of
4407
             it.  */
4408
          if (sv)
4409
            {
4410
              value_address = gen_reg_rtx (Pmode);
4411
              emit_move_insn (value_address, sv);
4412
            }
4413
        }
4414
      if (value_address)
4415
        {
4416
          rtx x = value_address;
4417
          if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4418
            {
4419
              x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4420
              set_mem_attributes (x, DECL_RESULT (subr), 1);
4421
            }
4422
          SET_DECL_RTL (DECL_RESULT (subr), x);
4423
        }
4424
    }
4425
  else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4426
    /* If return mode is void, this decl rtl should not be used.  */
4427
    SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4428
  else
4429
    {
4430
      /* Compute the return values into a pseudo reg, which we will copy
4431
         into the true return register after the cleanups are done.  */
4432
      tree return_type = TREE_TYPE (DECL_RESULT (subr));
4433
      if (TYPE_MODE (return_type) != BLKmode
4434
          && targetm.calls.return_in_msb (return_type))
4435
        /* expand_function_end will insert the appropriate padding in
4436
           this case.  Use the return value's natural (unpadded) mode
4437
           within the function proper.  */
4438
        SET_DECL_RTL (DECL_RESULT (subr),
4439
                      gen_reg_rtx (TYPE_MODE (return_type)));
4440
      else
4441
        {
4442
          /* In order to figure out what mode to use for the pseudo, we
4443
             figure out what the mode of the eventual return register will
4444
             actually be, and use that.  */
4445
          rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4446
 
4447
          /* Structures that are returned in registers are not
4448
             aggregate_value_p, so we may see a PARALLEL or a REG.  */
4449
          if (REG_P (hard_reg))
4450
            SET_DECL_RTL (DECL_RESULT (subr),
4451
                          gen_reg_rtx (GET_MODE (hard_reg)));
4452
          else
4453
            {
4454
              gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4455
              SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4456
            }
4457
        }
4458
 
4459
      /* Set DECL_REGISTER flag so that expand_function_end will copy the
4460
         result to the real return register(s).  */
4461
      DECL_REGISTER (DECL_RESULT (subr)) = 1;
4462
    }
4463
 
4464
  /* Initialize rtx for parameters and local variables.
4465
     In some cases this requires emitting insns.  */
4466
  assign_parms (subr);
4467
 
4468
  /* If function gets a static chain arg, store it.  */
4469
  if (cfun->static_chain_decl)
4470
    {
4471
      tree parm = cfun->static_chain_decl;
4472
      rtx local, chain, insn;
4473
 
4474
      local = gen_reg_rtx (Pmode);
4475
      chain = targetm.calls.static_chain (current_function_decl, true);
4476
 
4477
      set_decl_incoming_rtl (parm, chain, false);
4478
      SET_DECL_RTL (parm, local);
4479
      mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4480
 
4481
      insn = emit_move_insn (local, chain);
4482
 
4483
      /* Mark the register as eliminable, similar to parameters.  */
4484
      if (MEM_P (chain)
4485
          && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4486
        set_unique_reg_note (insn, REG_EQUIV, chain);
4487
    }
4488
 
4489
  /* If the function receives a non-local goto, then store the
4490
     bits we need to restore the frame pointer.  */
4491
  if (cfun->nonlocal_goto_save_area)
4492
    {
4493
      tree t_save;
4494
      rtx r_save;
4495
 
4496
      /* ??? We need to do this save early.  Unfortunately here is
4497
         before the frame variable gets declared.  Help out...  */
4498
      tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4499
      if (!DECL_RTL_SET_P (var))
4500
        expand_decl (var);
4501
 
4502
      t_save = build4 (ARRAY_REF, ptr_type_node,
4503
                       cfun->nonlocal_goto_save_area,
4504
                       integer_zero_node, NULL_TREE, NULL_TREE);
4505
      r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4506
      r_save = convert_memory_address (Pmode, r_save);
4507
 
4508
      emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4509
      update_nonlocal_goto_save_area ();
4510
    }
4511
 
4512
  /* The following was moved from init_function_start.
4513
     The move is supposed to make sdb output more accurate.  */
4514
  /* Indicate the beginning of the function body,
4515
     as opposed to parm setup.  */
4516
  emit_note (NOTE_INSN_FUNCTION_BEG);
4517
 
4518
  gcc_assert (NOTE_P (get_last_insn ()));
4519
 
4520
  parm_birth_insn = get_last_insn ();
4521
 
4522
  if (crtl->profile)
4523
    {
4524
#ifdef PROFILE_HOOK
4525
      PROFILE_HOOK (current_function_funcdef_no);
4526
#endif
4527
    }
4528
 
4529
  /* After the display initializations is where the stack checking
4530
     probe should go.  */
4531
  if(flag_stack_check)
4532
    stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4533
 
4534
  /* Make sure there is a line number after the function entry setup code.  */
4535
  force_next_line_note ();
4536
}
4537
 
4538
/* Undo the effects of init_dummy_function_start.  */
4539
void
4540
expand_dummy_function_end (void)
4541
{
4542
  gcc_assert (in_dummy_function);
4543
 
4544
  /* End any sequences that failed to be closed due to syntax errors.  */
4545
  while (in_sequence_p ())
4546
    end_sequence ();
4547
 
4548
  /* Outside function body, can't compute type's actual size
4549
     until next function's body starts.  */
4550
 
4551
  free_after_parsing (cfun);
4552
  free_after_compilation (cfun);
4553
  pop_cfun ();
4554
  in_dummy_function = false;
4555
}
4556
 
4557
/* Call DOIT for each hard register used as a return value from
4558
   the current function.  */
4559
 
4560
void
4561
diddle_return_value (void (*doit) (rtx, void *), void *arg)
4562
{
4563
  rtx outgoing = crtl->return_rtx;
4564
 
4565
  if (! outgoing)
4566
    return;
4567
 
4568
  if (REG_P (outgoing))
4569
    (*doit) (outgoing, arg);
4570
  else if (GET_CODE (outgoing) == PARALLEL)
4571
    {
4572
      int i;
4573
 
4574
      for (i = 0; i < XVECLEN (outgoing, 0); i++)
4575
        {
4576
          rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4577
 
4578
          if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4579
            (*doit) (x, arg);
4580
        }
4581
    }
4582
}
4583
 
4584
static void
4585
do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4586
{
4587
  emit_clobber (reg);
4588
}
4589
 
4590
void
4591
clobber_return_register (void)
4592
{
4593
  diddle_return_value (do_clobber_return_reg, NULL);
4594
 
4595
  /* In case we do use pseudo to return value, clobber it too.  */
4596
  if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4597
    {
4598
      tree decl_result = DECL_RESULT (current_function_decl);
4599
      rtx decl_rtl = DECL_RTL (decl_result);
4600
      if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4601
        {
4602
          do_clobber_return_reg (decl_rtl, NULL);
4603
        }
4604
    }
4605
}
4606
 
4607
static void
4608
do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4609
{
4610
  emit_use (reg);
4611
}
4612
 
4613
static void
4614
use_return_register (void)
4615
{
4616
  diddle_return_value (do_use_return_reg, NULL);
4617
}
4618
 
4619
/* Possibly warn about unused parameters.  */
4620
void
4621
do_warn_unused_parameter (tree fn)
4622
{
4623
  tree decl;
4624
 
4625
  for (decl = DECL_ARGUMENTS (fn);
4626
       decl; decl = TREE_CHAIN (decl))
4627
    if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4628
        && DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4629
        && !TREE_NO_WARNING (decl))
4630
      warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4631
}
4632
 
4633
static GTY(()) rtx initial_trampoline;
4634
 
4635
/* Generate RTL for the end of the current function.  */
4636
 
4637
void
4638
expand_function_end (void)
4639
{
4640
  rtx clobber_after;
4641
 
4642
  /* If arg_pointer_save_area was referenced only from a nested
4643
     function, we will not have initialized it yet.  Do that now.  */
4644
  if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4645
    get_arg_pointer_save_area ();
4646
 
4647
  /* If we are doing generic stack checking and this function makes calls,
4648
     do a stack probe at the start of the function to ensure we have enough
4649
     space for another stack frame.  */
4650
  if (flag_stack_check == GENERIC_STACK_CHECK)
4651
    {
4652
      rtx insn, seq;
4653
 
4654
      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4655
        if (CALL_P (insn))
4656
          {
4657
            rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4658
            start_sequence ();
4659
            if (STACK_CHECK_MOVING_SP)
4660
              anti_adjust_stack_and_probe (max_frame_size, true);
4661
            else
4662
              probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4663
            seq = get_insns ();
4664
            end_sequence ();
4665
            emit_insn_before (seq, stack_check_probe_note);
4666
            break;
4667
          }
4668
    }
4669
 
4670
  /* End any sequences that failed to be closed due to syntax errors.  */
4671
  while (in_sequence_p ())
4672
    end_sequence ();
4673
 
4674
  clear_pending_stack_adjust ();
4675
  do_pending_stack_adjust ();
4676
 
4677
  /* Output a linenumber for the end of the function.
4678
     SDB depends on this.  */
4679
  force_next_line_note ();
4680
  set_curr_insn_source_location (input_location);
4681
 
4682
  /* Before the return label (if any), clobber the return
4683
     registers so that they are not propagated live to the rest of
4684
     the function.  This can only happen with functions that drop
4685
     through; if there had been a return statement, there would
4686
     have either been a return rtx, or a jump to the return label.
4687
 
4688
     We delay actual code generation after the current_function_value_rtx
4689
     is computed.  */
4690
  clobber_after = get_last_insn ();
4691
 
4692
  /* Output the label for the actual return from the function.  */
4693
  emit_label (return_label);
4694
 
4695
  if (USING_SJLJ_EXCEPTIONS)
4696
    {
4697
      /* Let except.c know where it should emit the call to unregister
4698
         the function context for sjlj exceptions.  */
4699
      if (flag_exceptions)
4700
        sjlj_emit_function_exit_after (get_last_insn ());
4701
    }
4702
  else
4703
    {
4704
      /* We want to ensure that instructions that may trap are not
4705
         moved into the epilogue by scheduling, because we don't
4706
         always emit unwind information for the epilogue.  */
4707
      if (flag_non_call_exceptions)
4708
        emit_insn (gen_blockage ());
4709
    }
4710
 
4711
  /* If this is an implementation of throw, do what's necessary to
4712
     communicate between __builtin_eh_return and the epilogue.  */
4713
  expand_eh_return ();
4714
 
4715
  /* If scalar return value was computed in a pseudo-reg, or was a named
4716
     return value that got dumped to the stack, copy that to the hard
4717
     return register.  */
4718
  if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4719
    {
4720
      tree decl_result = DECL_RESULT (current_function_decl);
4721
      rtx decl_rtl = DECL_RTL (decl_result);
4722
 
4723
      if (REG_P (decl_rtl)
4724
          ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4725
          : DECL_REGISTER (decl_result))
4726
        {
4727
          rtx real_decl_rtl = crtl->return_rtx;
4728
 
4729
          /* This should be set in assign_parms.  */
4730
          gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4731
 
4732
          /* If this is a BLKmode structure being returned in registers,
4733
             then use the mode computed in expand_return.  Note that if
4734
             decl_rtl is memory, then its mode may have been changed,
4735
             but that crtl->return_rtx has not.  */
4736
          if (GET_MODE (real_decl_rtl) == BLKmode)
4737
            PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4738
 
4739
          /* If a non-BLKmode return value should be padded at the least
4740
             significant end of the register, shift it left by the appropriate
4741
             amount.  BLKmode results are handled using the group load/store
4742
             machinery.  */
4743
          if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4744
              && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4745
            {
4746
              emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4747
                                           REGNO (real_decl_rtl)),
4748
                              decl_rtl);
4749
              shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4750
            }
4751
          /* If a named return value dumped decl_return to memory, then
4752
             we may need to re-do the PROMOTE_MODE signed/unsigned
4753
             extension.  */
4754
          else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4755
            {
4756
              int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4757
              promote_function_mode (TREE_TYPE (decl_result),
4758
                                     GET_MODE (decl_rtl), &unsignedp,
4759
                                     TREE_TYPE (current_function_decl), 1);
4760
 
4761
              convert_move (real_decl_rtl, decl_rtl, unsignedp);
4762
            }
4763
          else if (GET_CODE (real_decl_rtl) == PARALLEL)
4764
            {
4765
              /* If expand_function_start has created a PARALLEL for decl_rtl,
4766
                 move the result to the real return registers.  Otherwise, do
4767
                 a group load from decl_rtl for a named return.  */
4768
              if (GET_CODE (decl_rtl) == PARALLEL)
4769
                emit_group_move (real_decl_rtl, decl_rtl);
4770
              else
4771
                emit_group_load (real_decl_rtl, decl_rtl,
4772
                                 TREE_TYPE (decl_result),
4773
                                 int_size_in_bytes (TREE_TYPE (decl_result)));
4774
            }
4775
          /* In the case of complex integer modes smaller than a word, we'll
4776
             need to generate some non-trivial bitfield insertions.  Do that
4777
             on a pseudo and not the hard register.  */
4778
          else if (GET_CODE (decl_rtl) == CONCAT
4779
                   && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4780
                   && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4781
            {
4782
              int old_generating_concat_p;
4783
              rtx tmp;
4784
 
4785
              old_generating_concat_p = generating_concat_p;
4786
              generating_concat_p = 0;
4787
              tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4788
              generating_concat_p = old_generating_concat_p;
4789
 
4790
              emit_move_insn (tmp, decl_rtl);
4791
              emit_move_insn (real_decl_rtl, tmp);
4792
            }
4793
          else
4794
            emit_move_insn (real_decl_rtl, decl_rtl);
4795
        }
4796
    }
4797
 
4798
  /* If returning a structure, arrange to return the address of the value
4799
     in a place where debuggers expect to find it.
4800
 
4801
     If returning a structure PCC style,
4802
     the caller also depends on this value.
4803
     And cfun->returns_pcc_struct is not necessarily set.  */
4804
  if (cfun->returns_struct
4805
      || cfun->returns_pcc_struct)
4806
    {
4807
      rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4808
      tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4809
      rtx outgoing;
4810
 
4811
      if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4812
        type = TREE_TYPE (type);
4813
      else
4814
        value_address = XEXP (value_address, 0);
4815
 
4816
      outgoing = targetm.calls.function_value (build_pointer_type (type),
4817
                                               current_function_decl, true);
4818
 
4819
      /* Mark this as a function return value so integrate will delete the
4820
         assignment and USE below when inlining this function.  */
4821
      REG_FUNCTION_VALUE_P (outgoing) = 1;
4822
 
4823
      /* The address may be ptr_mode and OUTGOING may be Pmode.  */
4824
      value_address = convert_memory_address (GET_MODE (outgoing),
4825
                                              value_address);
4826
 
4827
      emit_move_insn (outgoing, value_address);
4828
 
4829
      /* Show return register used to hold result (in this case the address
4830
         of the result.  */
4831
      crtl->return_rtx = outgoing;
4832
    }
4833
 
4834
  /* Emit the actual code to clobber return register.  */
4835
  {
4836
    rtx seq;
4837
 
4838
    start_sequence ();
4839
    clobber_return_register ();
4840
    seq = get_insns ();
4841
    end_sequence ();
4842
 
4843
    emit_insn_after (seq, clobber_after);
4844
  }
4845
 
4846
  /* Output the label for the naked return from the function.  */
4847
  if (naked_return_label)
4848
    emit_label (naked_return_label);
4849
 
4850
  /* @@@ This is a kludge.  We want to ensure that instructions that
4851
     may trap are not moved into the epilogue by scheduling, because
4852
     we don't always emit unwind information for the epilogue.  */
4853
  if (! USING_SJLJ_EXCEPTIONS && flag_non_call_exceptions)
4854
    emit_insn (gen_blockage ());
4855
 
4856
  /* If stack protection is enabled for this function, check the guard.  */
4857
  if (crtl->stack_protect_guard)
4858
    stack_protect_epilogue ();
4859
 
4860
  /* If we had calls to alloca, and this machine needs
4861
     an accurate stack pointer to exit the function,
4862
     insert some code to save and restore the stack pointer.  */
4863
  if (! EXIT_IGNORE_STACK
4864
      && cfun->calls_alloca)
4865
    {
4866
      rtx tem = 0;
4867
 
4868
      emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4869
      emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4870
    }
4871
 
4872
  /* ??? This should no longer be necessary since stupid is no longer with
4873
     us, but there are some parts of the compiler (eg reload_combine, and
4874
     sh mach_dep_reorg) that still try and compute their own lifetime info
4875
     instead of using the general framework.  */
4876
  use_return_register ();
4877
}
4878
 
4879
rtx
4880
get_arg_pointer_save_area (void)
4881
{
4882
  rtx ret = arg_pointer_save_area;
4883
 
4884
  if (! ret)
4885
    {
4886
      ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4887
      arg_pointer_save_area = ret;
4888
    }
4889
 
4890
  if (! crtl->arg_pointer_save_area_init)
4891
    {
4892
      rtx seq;
4893
 
4894
      /* Save the arg pointer at the beginning of the function.  The
4895
         generated stack slot may not be a valid memory address, so we
4896
         have to check it and fix it if necessary.  */
4897
      start_sequence ();
4898
      emit_move_insn (validize_mem (ret),
4899
                      crtl->args.internal_arg_pointer);
4900
      seq = get_insns ();
4901
      end_sequence ();
4902
 
4903
      push_topmost_sequence ();
4904
      emit_insn_after (seq, entry_of_function ());
4905
      pop_topmost_sequence ();
4906
    }
4907
 
4908
  return ret;
4909
}
4910
 
4911
/* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4912
   for the first time.  */
4913
 
4914
static void
4915
record_insns (rtx insns, rtx end, htab_t *hashp)
4916
{
4917
  rtx tmp;
4918
  htab_t hash = *hashp;
4919
 
4920
  if (hash == NULL)
4921
    *hashp = hash
4922
      = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
4923
 
4924
  for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
4925
    {
4926
      void **slot = htab_find_slot (hash, tmp, INSERT);
4927
      gcc_assert (*slot == NULL);
4928
      *slot = tmp;
4929
    }
4930
}
4931
 
4932
/* INSN has been duplicated as COPY, as part of duping a basic block.
4933
   If INSN is an epilogue insn, then record COPY as epilogue as well.  */
4934
 
4935
void
4936
maybe_copy_epilogue_insn (rtx insn, rtx copy)
4937
{
4938
  void **slot;
4939
 
4940
  if (epilogue_insn_hash == NULL
4941
      || htab_find (epilogue_insn_hash, insn) == NULL)
4942
    return;
4943
 
4944
  slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
4945
  gcc_assert (*slot == NULL);
4946
  *slot = copy;
4947
}
4948
 
4949
/* Set the locator of the insn chain starting at INSN to LOC.  */
4950
static void
4951
set_insn_locators (rtx insn, int loc)
4952
{
4953
  while (insn != NULL_RTX)
4954
    {
4955
      if (INSN_P (insn))
4956
        INSN_LOCATOR (insn) = loc;
4957
      insn = NEXT_INSN (insn);
4958
    }
4959
}
4960
 
4961
/* Determine if any INSNs in HASH are, or are part of, INSN.  Because
4962
   we can be running after reorg, SEQUENCE rtl is possible.  */
4963
 
4964
static bool
4965
contains (const_rtx insn, htab_t hash)
4966
{
4967
  if (hash == NULL)
4968
    return false;
4969
 
4970
  if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
4971
    {
4972
      int i;
4973
      for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4974
        if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
4975
          return true;
4976
      return false;
4977
    }
4978
 
4979
  return htab_find (hash, insn) != NULL;
4980
}
4981
 
4982
int
4983
prologue_epilogue_contains (const_rtx insn)
4984
{
4985
  if (contains (insn, prologue_insn_hash))
4986
    return 1;
4987
  if (contains (insn, epilogue_insn_hash))
4988
    return 1;
4989
  return 0;
4990
}
4991
 
4992
#ifdef HAVE_return
4993
/* Insert gen_return at the end of block BB.  This also means updating
4994
   block_for_insn appropriately.  */
4995
 
4996
static void
4997
emit_return_into_block (basic_block bb)
4998
{
4999
  emit_jump_insn_after (gen_return (), BB_END (bb));
5000
}
5001
#endif /* HAVE_return */
5002
 
5003
/* Generate the prologue and epilogue RTL if the machine supports it.  Thread
5004
   this into place with notes indicating where the prologue ends and where
5005
   the epilogue begins.  Update the basic block information when possible.  */
5006
 
5007
static void
5008
thread_prologue_and_epilogue_insns (void)
5009
{
5010
  int inserted = 0;
5011
  edge e;
5012
#if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5013
  rtx seq;
5014
#endif
5015
#if defined (HAVE_epilogue) || defined(HAVE_return)
5016
  rtx epilogue_end = NULL_RTX;
5017
#endif
5018
  edge_iterator ei;
5019
 
5020
  rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5021
#ifdef HAVE_prologue
5022
  if (HAVE_prologue)
5023
    {
5024
      start_sequence ();
5025
      seq = gen_prologue ();
5026
      emit_insn (seq);
5027
 
5028
      /* Insert an explicit USE for the frame pointer
5029
         if the profiling is on and the frame pointer is required.  */
5030
      if (crtl->profile && frame_pointer_needed)
5031
        emit_use (hard_frame_pointer_rtx);
5032
 
5033
      /* Retain a map of the prologue insns.  */
5034
      record_insns (seq, NULL, &prologue_insn_hash);
5035
      emit_note (NOTE_INSN_PROLOGUE_END);
5036
 
5037
#ifndef PROFILE_BEFORE_PROLOGUE
5038
      /* Ensure that instructions are not moved into the prologue when
5039
         profiling is on.  The call to the profiling routine can be
5040
         emitted within the live range of a call-clobbered register.  */
5041
      if (crtl->profile)
5042
        emit_insn (gen_blockage ());
5043
#endif
5044
 
5045
      seq = get_insns ();
5046
      end_sequence ();
5047
      set_insn_locators (seq, prologue_locator);
5048
 
5049
      /* Can't deal with multiple successors of the entry block
5050
         at the moment.  Function should always have at least one
5051
         entry point.  */
5052
      gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5053
 
5054
      insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5055
      inserted = 1;
5056
    }
5057
#endif
5058
 
5059
  /* If the exit block has no non-fake predecessors, we don't need
5060
     an epilogue.  */
5061
  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5062
    if ((e->flags & EDGE_FAKE) == 0)
5063
      break;
5064
  if (e == NULL)
5065
    goto epilogue_done;
5066
 
5067
  rtl_profile_for_bb (EXIT_BLOCK_PTR);
5068
#ifdef HAVE_return
5069
  if (optimize && HAVE_return)
5070
    {
5071
      /* If we're allowed to generate a simple return instruction,
5072
         then by definition we don't need a full epilogue.  Examine
5073
         the block that falls through to EXIT.   If it does not
5074
         contain any code, examine its predecessors and try to
5075
         emit (conditional) return instructions.  */
5076
 
5077
      basic_block last;
5078
      rtx label;
5079
 
5080
      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5081
        if (e->flags & EDGE_FALLTHRU)
5082
          break;
5083
      if (e == NULL)
5084
        goto epilogue_done;
5085
      last = e->src;
5086
 
5087
      /* Verify that there are no active instructions in the last block.  */
5088
      label = BB_END (last);
5089
      while (label && !LABEL_P (label))
5090
        {
5091
          if (active_insn_p (label))
5092
            break;
5093
          label = PREV_INSN (label);
5094
        }
5095
 
5096
      if (BB_HEAD (last) == label && LABEL_P (label))
5097
        {
5098
          edge_iterator ei2;
5099
 
5100
          for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5101
            {
5102
              basic_block bb = e->src;
5103
              rtx jump;
5104
 
5105
              if (bb == ENTRY_BLOCK_PTR)
5106
                {
5107
                  ei_next (&ei2);
5108
                  continue;
5109
                }
5110
 
5111
              jump = BB_END (bb);
5112
              if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5113
                {
5114
                  ei_next (&ei2);
5115
                  continue;
5116
                }
5117
 
5118
              /* If we have an unconditional jump, we can replace that
5119
                 with a simple return instruction.  */
5120
              if (simplejump_p (jump))
5121
                {
5122
                  emit_return_into_block (bb);
5123
                  delete_insn (jump);
5124
                }
5125
 
5126
              /* If we have a conditional jump, we can try to replace
5127
                 that with a conditional return instruction.  */
5128
              else if (condjump_p (jump))
5129
                {
5130
                  if (! redirect_jump (jump, 0, 0))
5131
                    {
5132
                      ei_next (&ei2);
5133
                      continue;
5134
                    }
5135
 
5136
                  /* If this block has only one successor, it both jumps
5137
                     and falls through to the fallthru block, so we can't
5138
                     delete the edge.  */
5139
                  if (single_succ_p (bb))
5140
                    {
5141
                      ei_next (&ei2);
5142
                      continue;
5143
                    }
5144
                }
5145
              else
5146
                {
5147
                  ei_next (&ei2);
5148
                  continue;
5149
                }
5150
 
5151
              /* Fix up the CFG for the successful change we just made.  */
5152
              redirect_edge_succ (e, EXIT_BLOCK_PTR);
5153
            }
5154
 
5155
          /* Emit a return insn for the exit fallthru block.  Whether
5156
             this is still reachable will be determined later.  */
5157
 
5158
          emit_barrier_after (BB_END (last));
5159
          emit_return_into_block (last);
5160
          epilogue_end = BB_END (last);
5161
          single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5162
          goto epilogue_done;
5163
        }
5164
    }
5165
#endif
5166
 
5167
  /* A small fib -- epilogue is not yet completed, but we wish to re-use
5168
     this marker for the splits of EH_RETURN patterns, and nothing else
5169
     uses the flag in the meantime.  */
5170
  epilogue_completed = 1;
5171
 
5172
#ifdef HAVE_eh_return
5173
  /* Find non-fallthru edges that end with EH_RETURN instructions.  On
5174
     some targets, these get split to a special version of the epilogue
5175
     code.  In order to be able to properly annotate these with unwind
5176
     info, try to split them now.  If we get a valid split, drop an
5177
     EPILOGUE_BEG note and mark the insns as epilogue insns.  */
5178
  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5179
    {
5180
      rtx prev, last, trial;
5181
 
5182
      if (e->flags & EDGE_FALLTHRU)
5183
        continue;
5184
      last = BB_END (e->src);
5185
      if (!eh_returnjump_p (last))
5186
        continue;
5187
 
5188
      prev = PREV_INSN (last);
5189
      trial = try_split (PATTERN (last), last, 1);
5190
      if (trial == last)
5191
        continue;
5192
 
5193
      record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5194
      emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5195
    }
5196
#endif
5197
 
5198
  /* Find the edge that falls through to EXIT.  Other edges may exist
5199
     due to RETURN instructions, but those don't need epilogues.
5200
     There really shouldn't be a mixture -- either all should have
5201
     been converted or none, however...  */
5202
 
5203
  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5204
    if (e->flags & EDGE_FALLTHRU)
5205
      break;
5206
  if (e == NULL)
5207
    goto epilogue_done;
5208
 
5209
#ifdef HAVE_epilogue
5210
  if (HAVE_epilogue)
5211
    {
5212
      start_sequence ();
5213
      epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5214
      seq = gen_epilogue ();
5215
      emit_jump_insn (seq);
5216
 
5217
      /* Retain a map of the epilogue insns.  */
5218
      record_insns (seq, NULL, &epilogue_insn_hash);
5219
      set_insn_locators (seq, epilogue_locator);
5220
 
5221
      seq = get_insns ();
5222
      end_sequence ();
5223
 
5224
      insert_insn_on_edge (seq, e);
5225
      inserted = 1;
5226
    }
5227
  else
5228
#endif
5229
    {
5230
      basic_block cur_bb;
5231
 
5232
      if (! next_active_insn (BB_END (e->src)))
5233
        goto epilogue_done;
5234
      /* We have a fall-through edge to the exit block, the source is not
5235
         at the end of the function, and there will be an assembler epilogue
5236
         at the end of the function.
5237
         We can't use force_nonfallthru here, because that would try to
5238
         use return.  Inserting a jump 'by hand' is extremely messy, so
5239
         we take advantage of cfg_layout_finalize using
5240
        fixup_fallthru_exit_predecessor.  */
5241
      cfg_layout_initialize (0);
5242
      FOR_EACH_BB (cur_bb)
5243
        if (cur_bb->index >= NUM_FIXED_BLOCKS
5244
            && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5245
          cur_bb->aux = cur_bb->next_bb;
5246
      cfg_layout_finalize ();
5247
    }
5248
epilogue_done:
5249
  default_rtl_profile ();
5250
 
5251
  if (inserted)
5252
    {
5253
      commit_edge_insertions ();
5254
 
5255
      /* The epilogue insns we inserted may cause the exit edge to no longer
5256
         be fallthru.  */
5257
      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5258
        {
5259
          if (((e->flags & EDGE_FALLTHRU) != 0)
5260
              && returnjump_p (BB_END (e->src)))
5261
            e->flags &= ~EDGE_FALLTHRU;
5262
        }
5263
    }
5264
 
5265
#ifdef HAVE_sibcall_epilogue
5266
  /* Emit sibling epilogues before any sibling call sites.  */
5267
  for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5268
    {
5269
      basic_block bb = e->src;
5270
      rtx insn = BB_END (bb);
5271
 
5272
      if (!CALL_P (insn)
5273
          || ! SIBLING_CALL_P (insn))
5274
        {
5275
          ei_next (&ei);
5276
          continue;
5277
        }
5278
 
5279
      start_sequence ();
5280
      emit_note (NOTE_INSN_EPILOGUE_BEG);
5281
      emit_insn (gen_sibcall_epilogue ());
5282
      seq = get_insns ();
5283
      end_sequence ();
5284
 
5285
      /* Retain a map of the epilogue insns.  Used in life analysis to
5286
         avoid getting rid of sibcall epilogue insns.  Do this before we
5287
         actually emit the sequence.  */
5288
      record_insns (seq, NULL, &epilogue_insn_hash);
5289
      set_insn_locators (seq, epilogue_locator);
5290
 
5291
      emit_insn_before (seq, insn);
5292
      ei_next (&ei);
5293
    }
5294
#endif
5295
 
5296
#ifdef HAVE_epilogue
5297
  if (epilogue_end)
5298
    {
5299
      rtx insn, next;
5300
 
5301
      /* Similarly, move any line notes that appear after the epilogue.
5302
         There is no need, however, to be quite so anal about the existence
5303
         of such a note.  Also possibly move
5304
         NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5305
         info generation.  */
5306
      for (insn = epilogue_end; insn; insn = next)
5307
        {
5308
          next = NEXT_INSN (insn);
5309
          if (NOTE_P (insn)
5310
              && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5311
            reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5312
        }
5313
    }
5314
#endif
5315
 
5316
  /* Threading the prologue and epilogue changes the artificial refs
5317
     in the entry and exit blocks.  */
5318
  epilogue_completed = 1;
5319
  df_update_entry_exit_and_calls ();
5320
}
5321
 
5322
/* Reposition the prologue-end and epilogue-begin notes after
5323
   instruction scheduling.  */
5324
 
5325
void
5326
reposition_prologue_and_epilogue_notes (void)
5327
{
5328
#if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5329
    || defined (HAVE_sibcall_epilogue)
5330
  /* Since the hash table is created on demand, the fact that it is
5331
     non-null is a signal that it is non-empty.  */
5332
  if (prologue_insn_hash != NULL)
5333
    {
5334
      size_t len = htab_elements (prologue_insn_hash);
5335
      rtx insn, last = NULL, note = NULL;
5336
 
5337
      /* Scan from the beginning until we reach the last prologue insn.  */
5338
      /* ??? While we do have the CFG intact, there are two problems:
5339
         (1) The prologue can contain loops (typically probing the stack),
5340
             which means that the end of the prologue isn't in the first bb.
5341
         (2) Sometimes the PROLOGUE_END note gets pushed into the next bb.  */
5342
      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5343
        {
5344
          if (NOTE_P (insn))
5345
            {
5346
              if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5347
                note = insn;
5348
            }
5349
          else if (contains (insn, prologue_insn_hash))
5350
            {
5351
              last = insn;
5352
              if (--len == 0)
5353
                break;
5354
            }
5355
        }
5356
 
5357
      if (last)
5358
        {
5359
          if (note == NULL)
5360
            {
5361
              /* Scan forward looking for the PROLOGUE_END note.  It should
5362
                 be right at the beginning of the block, possibly with other
5363
                 insn notes that got moved there.  */
5364
              for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5365
                {
5366
                  if (NOTE_P (note)
5367
                      && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5368
                    break;
5369
                }
5370
            }
5371
 
5372
          /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note.  */
5373
          if (LABEL_P (last))
5374
            last = NEXT_INSN (last);
5375
          reorder_insns (note, note, last);
5376
        }
5377
    }
5378
 
5379
  if (epilogue_insn_hash != NULL)
5380
    {
5381
      edge_iterator ei;
5382
      edge e;
5383
 
5384
      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5385
        {
5386
          rtx insn, first = NULL, note = NULL;
5387
          basic_block bb = e->src;
5388
 
5389
          /* Scan from the beginning until we reach the first epilogue insn. */
5390
          FOR_BB_INSNS (bb, insn)
5391
            {
5392
              if (NOTE_P (insn))
5393
                {
5394
                  if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5395
                    {
5396
                      note = insn;
5397
                      if (first != NULL)
5398
                        break;
5399
                    }
5400
                }
5401
              else if (first == NULL && contains (insn, epilogue_insn_hash))
5402
                {
5403
                  first = insn;
5404
                  if (note != NULL)
5405
                    break;
5406
                }
5407
            }
5408
 
5409
          if (note)
5410
            {
5411
              /* If the function has a single basic block, and no real
5412
                 epilogue insns (e.g. sibcall with no cleanup), the
5413
                 epilogue note can get scheduled before the prologue
5414
                 note.  If we have frame related prologue insns, having
5415
                 them scanned during the epilogue will result in a crash.
5416
                 In this case re-order the epilogue note to just before
5417
                 the last insn in the block.  */
5418
              if (first == NULL)
5419
                first = BB_END (bb);
5420
 
5421
              if (PREV_INSN (first) != note)
5422
                reorder_insns (note, note, PREV_INSN (first));
5423
            }
5424
        }
5425
    }
5426
#endif /* HAVE_prologue or HAVE_epilogue */
5427
}
5428
 
5429
/* Returns the name of the current function.  */
5430
const char *
5431
current_function_name (void)
5432
{
5433
  if (cfun == NULL)
5434
    return "<none>";
5435
  return lang_hooks.decl_printable_name (cfun->decl, 2);
5436
}
5437
 
5438
 
5439
static unsigned int
5440
rest_of_handle_check_leaf_regs (void)
5441
{
5442
#ifdef LEAF_REGISTERS
5443
  current_function_uses_only_leaf_regs
5444
    = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5445
#endif
5446
  return 0;
5447
}
5448
 
5449
/* Insert a TYPE into the used types hash table of CFUN.  */
5450
 
5451
static void
5452
used_types_insert_helper (tree type, struct function *func)
5453
{
5454
  if (type != NULL && func != NULL)
5455
    {
5456
      void **slot;
5457
 
5458
      if (func->used_types_hash == NULL)
5459
        func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5460
                                                 htab_eq_pointer, NULL);
5461
      slot = htab_find_slot (func->used_types_hash, type, INSERT);
5462
      if (*slot == NULL)
5463
        *slot = type;
5464
    }
5465
}
5466
 
5467
/* Given a type, insert it into the used hash table in cfun.  */
5468
void
5469
used_types_insert (tree t)
5470
{
5471
  while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5472
    if (TYPE_NAME (t))
5473
      break;
5474
    else
5475
      t = TREE_TYPE (t);
5476
  if (TYPE_NAME (t) == NULL_TREE
5477
      || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
5478
    t = TYPE_MAIN_VARIANT (t);
5479
  if (debug_info_level > DINFO_LEVEL_NONE)
5480
    {
5481
      if (cfun)
5482
        used_types_insert_helper (t, cfun);
5483
      else
5484
        /* So this might be a type referenced by a global variable.
5485
           Record that type so that we can later decide to emit its debug
5486
           information.  */
5487
        types_used_by_cur_var_decl =
5488
          tree_cons (t, NULL, types_used_by_cur_var_decl);
5489
 
5490
    }
5491
}
5492
 
5493
/* Helper to Hash a struct types_used_by_vars_entry.  */
5494
 
5495
static hashval_t
5496
hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5497
{
5498
  gcc_assert (entry && entry->var_decl && entry->type);
5499
 
5500
  return iterative_hash_object (entry->type,
5501
                                iterative_hash_object (entry->var_decl, 0));
5502
}
5503
 
5504
/* Hash function of the types_used_by_vars_entry hash table.  */
5505
 
5506
hashval_t
5507
types_used_by_vars_do_hash (const void *x)
5508
{
5509
  const struct types_used_by_vars_entry *entry =
5510
    (const struct types_used_by_vars_entry *) x;
5511
 
5512
  return hash_types_used_by_vars_entry (entry);
5513
}
5514
 
5515
/*Equality function of the types_used_by_vars_entry hash table.  */
5516
 
5517
int
5518
types_used_by_vars_eq (const void *x1, const void *x2)
5519
{
5520
  const struct types_used_by_vars_entry *e1 =
5521
    (const struct types_used_by_vars_entry *) x1;
5522
  const struct types_used_by_vars_entry *e2 =
5523
    (const struct types_used_by_vars_entry *)x2;
5524
 
5525
  return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5526
}
5527
 
5528
/* Inserts an entry into the types_used_by_vars_hash hash table. */
5529
 
5530
void
5531
types_used_by_var_decl_insert (tree type, tree var_decl)
5532
{
5533
  if (type != NULL && var_decl != NULL)
5534
    {
5535
      void **slot;
5536
      struct types_used_by_vars_entry e;
5537
      e.var_decl = var_decl;
5538
      e.type = type;
5539
      if (types_used_by_vars_hash == NULL)
5540
        types_used_by_vars_hash =
5541
          htab_create_ggc (37, types_used_by_vars_do_hash,
5542
                           types_used_by_vars_eq, NULL);
5543
      slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5544
                                       hash_types_used_by_vars_entry (&e), INSERT);
5545
      if (*slot == NULL)
5546
        {
5547
          struct types_used_by_vars_entry *entry;
5548
          entry = (struct types_used_by_vars_entry*) ggc_alloc
5549
                    (sizeof (struct types_used_by_vars_entry));
5550
          entry->type = type;
5551
          entry->var_decl = var_decl;
5552
          *slot = entry;
5553
        }
5554
    }
5555
}
5556
 
5557
struct rtl_opt_pass pass_leaf_regs =
5558
{
5559
 {
5560
  RTL_PASS,
5561
  "*leaf_regs",                         /* name */
5562
  NULL,                                 /* gate */
5563
  rest_of_handle_check_leaf_regs,       /* execute */
5564
  NULL,                                 /* sub */
5565
  NULL,                                 /* next */
5566
  0,                                    /* static_pass_number */
5567
  TV_NONE,                              /* tv_id */
5568
  0,                                    /* properties_required */
5569
  0,                                    /* properties_provided */
5570
  0,                                    /* properties_destroyed */
5571
  0,                                    /* todo_flags_start */
5572
 
5573
 }
5574
};
5575
 
5576
static unsigned int
5577
rest_of_handle_thread_prologue_and_epilogue (void)
5578
{
5579
  if (optimize)
5580
    cleanup_cfg (CLEANUP_EXPENSIVE);
5581
  /* On some machines, the prologue and epilogue code, or parts thereof,
5582
     can be represented as RTL.  Doing so lets us schedule insns between
5583
     it and the rest of the code and also allows delayed branch
5584
     scheduling to operate in the epilogue.  */
5585
 
5586
  thread_prologue_and_epilogue_insns ();
5587
  return 0;
5588
}
5589
 
5590
struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5591
{
5592
 {
5593
  RTL_PASS,
5594
  "pro_and_epilogue",                   /* name */
5595
  NULL,                                 /* gate */
5596
  rest_of_handle_thread_prologue_and_epilogue, /* execute */
5597
  NULL,                                 /* sub */
5598
  NULL,                                 /* next */
5599
  0,                                    /* static_pass_number */
5600
  TV_THREAD_PROLOGUE_AND_EPILOGUE,      /* tv_id */
5601
  0,                                    /* properties_required */
5602
  0,                                    /* properties_provided */
5603
  0,                                    /* properties_destroyed */
5604
  TODO_verify_flow,                     /* todo_flags_start */
5605
  TODO_dump_func |
5606
  TODO_df_verify |
5607
  TODO_df_finish | TODO_verify_rtl_sharing |
5608
  TODO_ggc_collect                      /* todo_flags_finish */
5609
 }
5610
};
5611
 
5612
 
5613
/* This mini-pass fixes fall-out from SSA in asm statements that have
5614
   in-out constraints.  Say you start with
5615
 
5616
     orig = inout;
5617
     asm ("": "+mr" (inout));
5618
     use (orig);
5619
 
5620
   which is transformed very early to use explicit output and match operands:
5621
 
5622
     orig = inout;
5623
     asm ("": "=mr" (inout) : "0" (inout));
5624
     use (orig);
5625
 
5626
   Or, after SSA and copyprop,
5627
 
5628
     asm ("": "=mr" (inout_2) : "0" (inout_1));
5629
     use (inout_1);
5630
 
5631
   Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5632
   they represent two separate values, so they will get different pseudo
5633
   registers during expansion.  Then, since the two operands need to match
5634
   per the constraints, but use different pseudo registers, reload can
5635
   only register a reload for these operands.  But reloads can only be
5636
   satisfied by hardregs, not by memory, so we need a register for this
5637
   reload, just because we are presented with non-matching operands.
5638
   So, even though we allow memory for this operand, no memory can be
5639
   used for it, just because the two operands don't match.  This can
5640
   cause reload failures on register-starved targets.
5641
 
5642
   So it's a symptom of reload not being able to use memory for reloads
5643
   or, alternatively it's also a symptom of both operands not coming into
5644
   reload as matching (in which case the pseudo could go to memory just
5645
   fine, as the alternative allows it, and no reload would be necessary).
5646
   We fix the latter problem here, by transforming
5647
 
5648
     asm ("": "=mr" (inout_2) : "0" (inout_1));
5649
 
5650
   back to
5651
 
5652
     inout_2 = inout_1;
5653
     asm ("": "=mr" (inout_2) : "0" (inout_2));  */
5654
 
5655
static void
5656
match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5657
{
5658
  int i;
5659
  bool changed = false;
5660
  rtx op = SET_SRC (p_sets[0]);
5661
  int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5662
  rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5663
  bool *output_matched = XALLOCAVEC (bool, noutputs);
5664
 
5665
  memset (output_matched, 0, noutputs * sizeof (bool));
5666
  for (i = 0; i < ninputs; i++)
5667
    {
5668
      rtx input, output, insns;
5669
      const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5670
      char *end;
5671
      int match, j;
5672
 
5673
      if (*constraint == '%')
5674
        constraint++;
5675
 
5676
      match = strtoul (constraint, &end, 10);
5677
      if (end == constraint)
5678
        continue;
5679
 
5680
      gcc_assert (match < noutputs);
5681
      output = SET_DEST (p_sets[match]);
5682
      input = RTVEC_ELT (inputs, i);
5683
      /* Only do the transformation for pseudos.  */
5684
      if (! REG_P (output)
5685
          || rtx_equal_p (output, input)
5686
          || (GET_MODE (input) != VOIDmode
5687
              && GET_MODE (input) != GET_MODE (output)))
5688
        continue;
5689
 
5690
      /* We can't do anything if the output is also used as input,
5691
         as we're going to overwrite it.  */
5692
      for (j = 0; j < ninputs; j++)
5693
        if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5694
          break;
5695
      if (j != ninputs)
5696
        continue;
5697
 
5698
      /* Avoid changing the same input several times.  For
5699
         asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5700
         only change in once (to out1), rather than changing it
5701
         first to out1 and afterwards to out2.  */
5702
      if (i > 0)
5703
        {
5704
          for (j = 0; j < noutputs; j++)
5705
            if (output_matched[j] && input == SET_DEST (p_sets[j]))
5706
              break;
5707
          if (j != noutputs)
5708
            continue;
5709
        }
5710
      output_matched[match] = true;
5711
 
5712
      start_sequence ();
5713
      emit_move_insn (output, input);
5714
      insns = get_insns ();
5715
      end_sequence ();
5716
      emit_insn_before (insns, insn);
5717
 
5718
      /* Now replace all mentions of the input with output.  We can't
5719
         just replace the occurrence in inputs[i], as the register might
5720
         also be used in some other input (or even in an address of an
5721
         output), which would mean possibly increasing the number of
5722
         inputs by one (namely 'output' in addition), which might pose
5723
         a too complicated problem for reload to solve.  E.g. this situation:
5724
 
5725
           asm ("" : "=r" (output), "=m" (input) : "0" (input))
5726
 
5727
         Here 'input' is used in two occurrences as input (once for the
5728
         input operand, once for the address in the second output operand).
5729
         If we would replace only the occurrence of the input operand (to
5730
         make the matching) we would be left with this:
5731
 
5732
           output = input
5733
           asm ("" : "=r" (output), "=m" (input) : "0" (output))
5734
 
5735
         Now we suddenly have two different input values (containing the same
5736
         value, but different pseudos) where we formerly had only one.
5737
         With more complicated asms this might lead to reload failures
5738
         which wouldn't have happen without this pass.  So, iterate over
5739
         all operands and replace all occurrences of the register used.  */
5740
      for (j = 0; j < noutputs; j++)
5741
        if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5742
            && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5743
          SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5744
                                              input, output);
5745
      for (j = 0; j < ninputs; j++)
5746
        if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5747
          RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5748
                                               input, output);
5749
 
5750
      changed = true;
5751
    }
5752
 
5753
  if (changed)
5754
    df_insn_rescan (insn);
5755
}
5756
 
5757
static unsigned
5758
rest_of_match_asm_constraints (void)
5759
{
5760
  basic_block bb;
5761
  rtx insn, pat, *p_sets;
5762
  int noutputs;
5763
 
5764
  if (!crtl->has_asm_statement)
5765
    return 0;
5766
 
5767
  df_set_flags (DF_DEFER_INSN_RESCAN);
5768
  FOR_EACH_BB (bb)
5769
    {
5770
      FOR_BB_INSNS (bb, insn)
5771
        {
5772
          if (!INSN_P (insn))
5773
            continue;
5774
 
5775
          pat = PATTERN (insn);
5776
          if (GET_CODE (pat) == PARALLEL)
5777
            p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5778
          else if (GET_CODE (pat) == SET)
5779
            p_sets = &PATTERN (insn), noutputs = 1;
5780
          else
5781
            continue;
5782
 
5783
          if (GET_CODE (*p_sets) == SET
5784
              && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5785
            match_asm_constraints_1 (insn, p_sets, noutputs);
5786
         }
5787
    }
5788
 
5789
  return TODO_df_finish;
5790
}
5791
 
5792
struct rtl_opt_pass pass_match_asm_constraints =
5793
{
5794
 {
5795
  RTL_PASS,
5796
  "asmcons",                            /* name */
5797
  NULL,                                 /* gate */
5798
  rest_of_match_asm_constraints,        /* execute */
5799
  NULL,                                 /* sub */
5800
  NULL,                                 /* next */
5801
  0,                                    /* static_pass_number */
5802
  TV_NONE,                              /* tv_id */
5803
  0,                                    /* properties_required */
5804
  0,                                    /* properties_provided */
5805
  0,                                    /* properties_destroyed */
5806
  0,                                     /* todo_flags_start */
5807
  TODO_dump_func                       /* todo_flags_finish */
5808
 }
5809
};
5810
 
5811
 
5812
#include "gt-function.h"

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