1/* Expands front end tree to back end RTL for GCC.
2   Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3   1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
4   2010  Free Software Foundation, Inc.
5
6This file is part of GCC.
7
8GCC is free software; you can redistribute it and/or modify it under
9the terms of the GNU General Public License as published by the Free
10Software Foundation; either version 3, or (at your option) any later
11version.
12
13GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14WARRANTY; without even the implied warranty of MERCHANTABILITY or
15FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16for more details.
17
18You should have received a copy of the GNU General Public License
19along 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.  */
99int 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.  */
104int 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.  */
109int 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.  */
115int virtuals_instantiated;
116
117/* Assign unique numbers to labels generated for profiling, debugging, etc.  */
118static GTY(()) int funcdef_no;
119
120/* These variables hold pointers to functions to create and destroy
121   target specific, per-function data structures.  */
122struct machine_function * (*init_machine_status) (void);
123
124/* The currently compiled function.  */
125struct function *cfun = 0;
126
127/* These hashes record the prologue and epilogue insns.  */
128static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
129  htab_t prologue_insn_hash;
130static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def)))
131  htab_t epilogue_insn_hash;
132
133
134htab_t types_used_by_vars_hash = NULL;
135tree types_used_by_cur_var_decl = NULL;
136
137/* Forward declarations.  */
138
139static struct temp_slot *find_temp_slot_from_address (rtx);
140static void pad_to_arg_alignment (struct args_size *, int, struct args_size *);
141static void pad_below (struct args_size *, enum machine_mode, tree);
142static void reorder_blocks_1 (rtx, tree, VEC(tree,heap) **);
143static int all_blocks (tree, tree *);
144static tree *get_block_vector (tree, int *);
145extern 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'.  */
148static void record_insns (rtx, rtx, htab_t *) ATTRIBUTE_UNUSED;
149static bool contains (const_rtx, htab_t);
150#ifdef HAVE_return
151static void emit_return_into_block (basic_block);
152#endif
153static void prepare_function_start (void);
154static void do_clobber_return_reg (rtx, void *);
155static void do_use_return_reg (rtx, void *);
156static void set_insn_locators (rtx, int) ATTRIBUTE_UNUSED;
157
158/* Stack of nested functions.  */
159/* Keep track of the cfun stack.  */
160
161typedef struct function *function_p;
162
163DEF_VEC_P(function_p);
164DEF_VEC_ALLOC_P(function_p,heap);
165static 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
170void
171push_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
183void
184pop_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
199void
200free_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
209void
210free_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
231HOST_WIDE_INT
232get_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
244bool
245frame_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
263static unsigned int
264get_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   0 means according to MODE,
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
294rtx
295assign_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
431rtx
432assign_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
456struct 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.  */
490static GTY((param_is(struct temp_slot_address_entry))) htab_t temp_slot_address_table;
491
492/* Entry for the above hash table.  */
493struct 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
501static void
502cut_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
516static void
517insert_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
528static struct temp_slot **
529temp_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
539static int
540max_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
550static void
551move_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
560static void
561make_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.  */
571static hashval_t
572temp_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.  */
580static hashval_t
581temp_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.  */
589static int
590temp_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.  */
599static void
600insert_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.  */
613static int
614remove_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.  */
624static void
625remove_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
634static struct temp_slot *
635find_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
693rtx
694assign_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
860rtx
861assign_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
876rtx
877assign_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
941static void
942combine_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
1005void
1006update_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
1054void
1055mark_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
1081void
1082preserve_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
1163void
1164free_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
1189void
1190push_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
1198void
1199pop_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
1222void
1223init_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
1247static int in_arg_offset;
1248static int var_offset;
1249static int dynamic_offset;
1250static int out_arg_offset;
1251static 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
1293static rtx
1294instantiate_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
1339static int
1340instantiate_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
1389static int
1390safe_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
1407static void
1408instantiate_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
1659void
1660instantiate_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
1693static tree
1694instantiate_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
1709static void
1710instantiate_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
1733static void
1734instantiate_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
1768static unsigned int
1769instantiate_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
1828struct 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
1853int
1854aggregate_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
1942bool
1943use_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
1998bool
1999pass_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
2028bool
2029reference_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
2041struct 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
2054struct 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
2073static void
2074assign_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
2098static void
2099split_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
2147static VEC(tree, heap) *
2148assign_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
2192static void
2193assign_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
2266static void
2267assign_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
2287static void
2288assign_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
2410static bool
2411assign_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
2444static void
2445assign_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
2509static void
2510assign_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
2570static void
2571assign_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
2593static void
2594assign_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
2630static bool
2631assign_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
2654static void
2655assign_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
2797static void
2798assign_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
2986static void
2987assign_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
3071static void
3072assign_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
3138static void
3139assign_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
3341static tree
3342gimplify_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
3367gimple_seq
3368gimplify_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.  Keep the parms address taken
3427		     as we'll query that flag during gimplification.  */
3428		  if (TREE_ADDRESSABLE (parm))
3429		    TREE_ADDRESSABLE (local) = 1;
3430		}
3431	      else
3432		{
3433		  tree ptr_type, addr;
3434
3435		  ptr_type = build_pointer_type (type);
3436		  addr = create_tmp_var (ptr_type, get_name (parm));
3437		  DECL_IGNORED_P (addr) = 0;
3438		  local = build_fold_indirect_ref (addr);
3439
3440		  t = built_in_decls[BUILT_IN_ALLOCA];
3441		  t = build_call_expr (t, 1, DECL_SIZE_UNIT (parm));
3442		  t = fold_convert (ptr_type, t);
3443		  t = build2 (MODIFY_EXPR, TREE_TYPE (addr), addr, t);
3444		  gimplify_and_add (t, &stmts);
3445		}
3446
3447	      gimplify_assign (local, parm, &stmts);
3448
3449	      SET_DECL_VALUE_EXPR (parm, local);
3450	      DECL_HAS_VALUE_EXPR_P (parm) = 1;
3451	    }
3452	}
3453    }
3454
3455  VEC_free (tree, heap, fnargs);
3456
3457  return stmts;
3458}
3459
3460/* Compute the size and offset from the start of the stacked arguments for a
3461   parm passed in mode PASSED_MODE and with type TYPE.
3462
3463   INITIAL_OFFSET_PTR points to the current offset into the stacked
3464   arguments.
3465
3466   The starting offset and size for this parm are returned in
3467   LOCATE->OFFSET and LOCATE->SIZE, respectively.  When IN_REGS is
3468   nonzero, the offset is that of stack slot, which is returned in
3469   LOCATE->SLOT_OFFSET.  LOCATE->ALIGNMENT_PAD is the amount of
3470   padding required from the initial offset ptr to the stack slot.
3471
3472   IN_REGS is nonzero if the argument will be passed in registers.  It will
3473   never be set if REG_PARM_STACK_SPACE is not defined.
3474
3475   FNDECL is the function in which the argument was defined.
3476
3477   There are two types of rounding that are done.  The first, controlled by
3478   FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3479   list to be aligned to the specific boundary (in bits).  This rounding
3480   affects the initial and starting offsets, but not the argument size.
3481
3482   The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3483   optionally rounds the size of the parm to PARM_BOUNDARY.  The
3484   initial offset is not affected by this rounding, while the size always
3485   is and the starting offset may be.  */
3486
3487/*  LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3488    INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3489    callers pass in the total size of args so far as
3490    INITIAL_OFFSET_PTR.  LOCATE->SIZE is always positive.  */
3491
3492void
3493locate_and_pad_parm (enum machine_mode passed_mode, tree type, int in_regs,
3494		     int partial, tree fndecl ATTRIBUTE_UNUSED,
3495		     struct args_size *initial_offset_ptr,
3496		     struct locate_and_pad_arg_data *locate)
3497{
3498  tree sizetree;
3499  enum direction where_pad;
3500  unsigned int boundary;
3501  int reg_parm_stack_space = 0;
3502  int part_size_in_regs;
3503
3504#ifdef REG_PARM_STACK_SPACE
3505  reg_parm_stack_space = REG_PARM_STACK_SPACE (fndecl);
3506
3507  /* If we have found a stack parm before we reach the end of the
3508     area reserved for registers, skip that area.  */
3509  if (! in_regs)
3510    {
3511      if (reg_parm_stack_space > 0)
3512	{
3513	  if (initial_offset_ptr->var)
3514	    {
3515	      initial_offset_ptr->var
3516		= size_binop (MAX_EXPR, ARGS_SIZE_TREE (*initial_offset_ptr),
3517			      ssize_int (reg_parm_stack_space));
3518	      initial_offset_ptr->constant = 0;
3519	    }
3520	  else if (initial_offset_ptr->constant < reg_parm_stack_space)
3521	    initial_offset_ptr->constant = reg_parm_stack_space;
3522	}
3523    }
3524#endif /* REG_PARM_STACK_SPACE */
3525
3526  part_size_in_regs = (reg_parm_stack_space == 0 ? partial : 0);
3527
3528  sizetree
3529    = type ? size_in_bytes (type) : size_int (GET_MODE_SIZE (passed_mode));
3530  where_pad = FUNCTION_ARG_PADDING (passed_mode, type);
3531  boundary = FUNCTION_ARG_BOUNDARY (passed_mode, type);
3532  locate->where_pad = where_pad;
3533
3534  /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT.  */
3535  if (boundary > MAX_SUPPORTED_STACK_ALIGNMENT)
3536    boundary = MAX_SUPPORTED_STACK_ALIGNMENT;
3537
3538  locate->boundary = boundary;
3539
3540  if (SUPPORTS_STACK_ALIGNMENT)
3541    {
3542      /* stack_alignment_estimated can't change after stack has been
3543	 realigned.  */
3544      if (crtl->stack_alignment_estimated < boundary)
3545        {
3546          if (!crtl->stack_realign_processed)
3547	    crtl->stack_alignment_estimated = boundary;
3548	  else
3549	    {
3550	      /* If stack is realigned and stack alignment value
3551		 hasn't been finalized, it is OK not to increase
3552		 stack_alignment_estimated.  The bigger alignment
3553		 requirement is recorded in stack_alignment_needed
3554		 below.  */
3555	      gcc_assert (!crtl->stack_realign_finalized
3556			  && crtl->stack_realign_needed);
3557	    }
3558	}
3559    }
3560
3561  /* Remember if the outgoing parameter requires extra alignment on the
3562     calling function side.  */
3563  if (crtl->stack_alignment_needed < boundary)
3564    crtl->stack_alignment_needed = boundary;
3565  if (crtl->preferred_stack_boundary < boundary)
3566    crtl->preferred_stack_boundary = boundary;
3567
3568#ifdef ARGS_GROW_DOWNWARD
3569  locate->slot_offset.constant = -initial_offset_ptr->constant;
3570  if (initial_offset_ptr->var)
3571    locate->slot_offset.var = size_binop (MINUS_EXPR, ssize_int (0),
3572					  initial_offset_ptr->var);
3573
3574  {
3575    tree s2 = sizetree;
3576    if (where_pad != none
3577	&& (!host_integerp (sizetree, 1)
3578	    || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3579      s2 = round_up (s2, PARM_BOUNDARY / BITS_PER_UNIT);
3580    SUB_PARM_SIZE (locate->slot_offset, s2);
3581  }
3582
3583  locate->slot_offset.constant += part_size_in_regs;
3584
3585  if (!in_regs
3586#ifdef REG_PARM_STACK_SPACE
3587      || REG_PARM_STACK_SPACE (fndecl) > 0
3588#endif
3589     )
3590    pad_to_arg_alignment (&locate->slot_offset, boundary,
3591			  &locate->alignment_pad);
3592
3593  locate->size.constant = (-initial_offset_ptr->constant
3594			   - locate->slot_offset.constant);
3595  if (initial_offset_ptr->var)
3596    locate->size.var = size_binop (MINUS_EXPR,
3597				   size_binop (MINUS_EXPR,
3598					       ssize_int (0),
3599					       initial_offset_ptr->var),
3600				   locate->slot_offset.var);
3601
3602  /* Pad_below needs the pre-rounded size to know how much to pad
3603     below.  */
3604  locate->offset = locate->slot_offset;
3605  if (where_pad == downward)
3606    pad_below (&locate->offset, passed_mode, sizetree);
3607
3608#else /* !ARGS_GROW_DOWNWARD */
3609  if (!in_regs
3610#ifdef REG_PARM_STACK_SPACE
3611      || REG_PARM_STACK_SPACE (fndecl) > 0
3612#endif
3613      )
3614    pad_to_arg_alignment (initial_offset_ptr, boundary,
3615			  &locate->alignment_pad);
3616  locate->slot_offset = *initial_offset_ptr;
3617
3618#ifdef PUSH_ROUNDING
3619  if (passed_mode != BLKmode)
3620    sizetree = size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree)));
3621#endif
3622
3623  /* Pad_below needs the pre-rounded size to know how much to pad below
3624     so this must be done before rounding up.  */
3625  locate->offset = locate->slot_offset;
3626  if (where_pad == downward)
3627    pad_below (&locate->offset, passed_mode, sizetree);
3628
3629  if (where_pad != none
3630      && (!host_integerp (sizetree, 1)
3631	  || (tree_low_cst (sizetree, 1) * BITS_PER_UNIT) % PARM_BOUNDARY))
3632    sizetree = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3633
3634  ADD_PARM_SIZE (locate->size, sizetree);
3635
3636  locate->size.constant -= part_size_in_regs;
3637#endif /* ARGS_GROW_DOWNWARD */
3638
3639#ifdef FUNCTION_ARG_OFFSET
3640  locate->offset.constant += FUNCTION_ARG_OFFSET (passed_mode, type);
3641#endif
3642}
3643
3644/* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3645   BOUNDARY is measured in bits, but must be a multiple of a storage unit.  */
3646
3647static void
3648pad_to_arg_alignment (struct args_size *offset_ptr, int boundary,
3649		      struct args_size *alignment_pad)
3650{
3651  tree save_var = NULL_TREE;
3652  HOST_WIDE_INT save_constant = 0;
3653  int boundary_in_bytes = boundary / BITS_PER_UNIT;
3654  HOST_WIDE_INT sp_offset = STACK_POINTER_OFFSET;
3655
3656#ifdef SPARC_STACK_BOUNDARY_HACK
3657  /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3658     the real alignment of %sp.  However, when it does this, the
3659     alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY.  */
3660  if (SPARC_STACK_BOUNDARY_HACK)
3661    sp_offset = 0;
3662#endif
3663
3664  if (boundary > PARM_BOUNDARY)
3665    {
3666      save_var = offset_ptr->var;
3667      save_constant = offset_ptr->constant;
3668    }
3669
3670  alignment_pad->var = NULL_TREE;
3671  alignment_pad->constant = 0;
3672
3673  if (boundary > BITS_PER_UNIT)
3674    {
3675      if (offset_ptr->var)
3676	{
3677	  tree sp_offset_tree = ssize_int (sp_offset);
3678	  tree offset = size_binop (PLUS_EXPR,
3679				    ARGS_SIZE_TREE (*offset_ptr),
3680				    sp_offset_tree);
3681#ifdef ARGS_GROW_DOWNWARD
3682	  tree rounded = round_down (offset, boundary / BITS_PER_UNIT);
3683#else
3684	  tree rounded = round_up   (offset, boundary / BITS_PER_UNIT);
3685#endif
3686
3687	  offset_ptr->var = size_binop (MINUS_EXPR, rounded, sp_offset_tree);
3688	  /* ARGS_SIZE_TREE includes constant term.  */
3689	  offset_ptr->constant = 0;
3690	  if (boundary > PARM_BOUNDARY)
3691	    alignment_pad->var = size_binop (MINUS_EXPR, offset_ptr->var,
3692					     save_var);
3693	}
3694      else
3695	{
3696	  offset_ptr->constant = -sp_offset +
3697#ifdef ARGS_GROW_DOWNWARD
3698	    FLOOR_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3699#else
3700	    CEIL_ROUND (offset_ptr->constant + sp_offset, boundary_in_bytes);
3701#endif
3702	    if (boundary > PARM_BOUNDARY)
3703	      alignment_pad->constant = offset_ptr->constant - save_constant;
3704	}
3705    }
3706}
3707
3708static void
3709pad_below (struct args_size *offset_ptr, enum machine_mode passed_mode, tree sizetree)
3710{
3711  if (passed_mode != BLKmode)
3712    {
3713      if (GET_MODE_BITSIZE (passed_mode) % PARM_BOUNDARY)
3714	offset_ptr->constant
3715	  += (((GET_MODE_BITSIZE (passed_mode) + PARM_BOUNDARY - 1)
3716	       / PARM_BOUNDARY * PARM_BOUNDARY / BITS_PER_UNIT)
3717	      - GET_MODE_SIZE (passed_mode));
3718    }
3719  else
3720    {
3721      if (TREE_CODE (sizetree) != INTEGER_CST
3722	  || (TREE_INT_CST_LOW (sizetree) * BITS_PER_UNIT) % PARM_BOUNDARY)
3723	{
3724	  /* Round the size up to multiple of PARM_BOUNDARY bits.  */
3725	  tree s2 = round_up (sizetree, PARM_BOUNDARY / BITS_PER_UNIT);
3726	  /* Add it in.  */
3727	  ADD_PARM_SIZE (*offset_ptr, s2);
3728	  SUB_PARM_SIZE (*offset_ptr, sizetree);
3729	}
3730    }
3731}
3732
3733
3734/* True if register REGNO was alive at a place where `setjmp' was
3735   called and was set more than once or is an argument.  Such regs may
3736   be clobbered by `longjmp'.  */
3737
3738static bool
3739regno_clobbered_at_setjmp (bitmap setjmp_crosses, int regno)
3740{
3741  /* There appear to be cases where some local vars never reach the
3742     backend but have bogus regnos.  */
3743  if (regno >= max_reg_num ())
3744    return false;
3745
3746  return ((REG_N_SETS (regno) > 1
3747	   || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR), regno))
3748	  && REGNO_REG_SET_P (setjmp_crosses, regno));
3749}
3750
3751/* Walk the tree of blocks describing the binding levels within a
3752   function and warn about variables the might be killed by setjmp or
3753   vfork.  This is done after calling flow_analysis before register
3754   allocation since that will clobber the pseudo-regs to hard
3755   regs.  */
3756
3757static void
3758setjmp_vars_warning (bitmap setjmp_crosses, tree block)
3759{
3760  tree decl, sub;
3761
3762  for (decl = BLOCK_VARS (block); decl; decl = TREE_CHAIN (decl))
3763    {
3764      if (TREE_CODE (decl) == VAR_DECL
3765	  && DECL_RTL_SET_P (decl)
3766	  && REG_P (DECL_RTL (decl))
3767	  && regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3768	warning (OPT_Wclobbered, "variable %q+D might be clobbered by"
3769                 " %<longjmp%> or %<vfork%>", decl);
3770    }
3771
3772  for (sub = BLOCK_SUBBLOCKS (block); sub; sub = BLOCK_CHAIN (sub))
3773    setjmp_vars_warning (setjmp_crosses, sub);
3774}
3775
3776/* Do the appropriate part of setjmp_vars_warning
3777   but for arguments instead of local variables.  */
3778
3779static void
3780setjmp_args_warning (bitmap setjmp_crosses)
3781{
3782  tree decl;
3783  for (decl = DECL_ARGUMENTS (current_function_decl);
3784       decl; decl = TREE_CHAIN (decl))
3785    if (DECL_RTL (decl) != 0
3786	&& REG_P (DECL_RTL (decl))
3787	&& regno_clobbered_at_setjmp (setjmp_crosses, REGNO (DECL_RTL (decl))))
3788      warning (OPT_Wclobbered,
3789               "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3790	       decl);
3791}
3792
3793/* Generate warning messages for variables live across setjmp.  */
3794
3795void
3796generate_setjmp_warnings (void)
3797{
3798  bitmap setjmp_crosses = regstat_get_setjmp_crosses ();
3799
3800  if (n_basic_blocks == NUM_FIXED_BLOCKS
3801      || bitmap_empty_p (setjmp_crosses))
3802    return;
3803
3804  setjmp_vars_warning (setjmp_crosses, DECL_INITIAL (current_function_decl));
3805  setjmp_args_warning (setjmp_crosses);
3806}
3807
3808
3809/* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3810   and create duplicate blocks.  */
3811/* ??? Need an option to either create block fragments or to create
3812   abstract origin duplicates of a source block.  It really depends
3813   on what optimization has been performed.  */
3814
3815void
3816reorder_blocks (void)
3817{
3818  tree block = DECL_INITIAL (current_function_decl);
3819  VEC(tree,heap) *block_stack;
3820
3821  if (block == NULL_TREE)
3822    return;
3823
3824  block_stack = VEC_alloc (tree, heap, 10);
3825
3826  /* Reset the TREE_ASM_WRITTEN bit for all blocks.  */
3827  clear_block_marks (block);
3828
3829  /* Prune the old trees away, so that they don't get in the way.  */
3830  BLOCK_SUBBLOCKS (block) = NULL_TREE;
3831  BLOCK_CHAIN (block) = NULL_TREE;
3832
3833  /* Recreate the block tree from the note nesting.  */
3834  reorder_blocks_1 (get_insns (), block, &block_stack);
3835  BLOCK_SUBBLOCKS (block) = blocks_nreverse (BLOCK_SUBBLOCKS (block));
3836
3837  VEC_free (tree, heap, block_stack);
3838}
3839
3840/* Helper function for reorder_blocks.  Reset TREE_ASM_WRITTEN.  */
3841
3842void
3843clear_block_marks (tree block)
3844{
3845  while (block)
3846    {
3847      TREE_ASM_WRITTEN (block) = 0;
3848      clear_block_marks (BLOCK_SUBBLOCKS (block));
3849      block = BLOCK_CHAIN (block);
3850    }
3851}
3852
3853static void
3854reorder_blocks_1 (rtx insns, tree current_block, VEC(tree,heap) **p_block_stack)
3855{
3856  rtx insn;
3857
3858  for (insn = insns; insn; insn = NEXT_INSN (insn))
3859    {
3860      if (NOTE_P (insn))
3861	{
3862	  if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_BEG)
3863	    {
3864	      tree block = NOTE_BLOCK (insn);
3865	      tree origin;
3866
3867	      origin = (BLOCK_FRAGMENT_ORIGIN (block)
3868			? BLOCK_FRAGMENT_ORIGIN (block)
3869			: block);
3870
3871	      /* If we have seen this block before, that means it now
3872		 spans multiple address regions.  Create a new fragment.  */
3873	      if (TREE_ASM_WRITTEN (block))
3874		{
3875		  tree new_block = copy_node (block);
3876
3877		  BLOCK_FRAGMENT_ORIGIN (new_block) = origin;
3878		  BLOCK_FRAGMENT_CHAIN (new_block)
3879		    = BLOCK_FRAGMENT_CHAIN (origin);
3880		  BLOCK_FRAGMENT_CHAIN (origin) = new_block;
3881
3882		  NOTE_BLOCK (insn) = new_block;
3883		  block = new_block;
3884		}
3885
3886	      BLOCK_SUBBLOCKS (block) = 0;
3887	      TREE_ASM_WRITTEN (block) = 1;
3888	      /* When there's only one block for the entire function,
3889		 current_block == block and we mustn't do this, it
3890		 will cause infinite recursion.  */
3891	      if (block != current_block)
3892		{
3893		  if (block != origin)
3894		    gcc_assert (BLOCK_SUPERCONTEXT (origin) == current_block);
3895
3896		  BLOCK_SUPERCONTEXT (block) = current_block;
3897		  BLOCK_CHAIN (block) = BLOCK_SUBBLOCKS (current_block);
3898		  BLOCK_SUBBLOCKS (current_block) = block;
3899		  current_block = origin;
3900		}
3901	      VEC_safe_push (tree, heap, *p_block_stack, block);
3902	    }
3903	  else if (NOTE_KIND (insn) == NOTE_INSN_BLOCK_END)
3904	    {
3905	      NOTE_BLOCK (insn) = VEC_pop (tree, *p_block_stack);
3906	      BLOCK_SUBBLOCKS (current_block)
3907		= blocks_nreverse (BLOCK_SUBBLOCKS (current_block));
3908	      current_block = BLOCK_SUPERCONTEXT (current_block);
3909	    }
3910	}
3911    }
3912}
3913
3914/* Reverse the order of elements in the chain T of blocks,
3915   and return the new head of the chain (old last element).  */
3916
3917tree
3918blocks_nreverse (tree t)
3919{
3920  tree prev = 0, decl, next;
3921  for (decl = t; decl; decl = next)
3922    {
3923      next = BLOCK_CHAIN (decl);
3924      BLOCK_CHAIN (decl) = prev;
3925      prev = decl;
3926    }
3927  return prev;
3928}
3929
3930/* Count the subblocks of the list starting with BLOCK.  If VECTOR is
3931   non-NULL, list them all into VECTOR, in a depth-first preorder
3932   traversal of the block tree.  Also clear TREE_ASM_WRITTEN in all
3933   blocks.  */
3934
3935static int
3936all_blocks (tree block, tree *vector)
3937{
3938  int n_blocks = 0;
3939
3940  while (block)
3941    {
3942      TREE_ASM_WRITTEN (block) = 0;
3943
3944      /* Record this block.  */
3945      if (vector)
3946	vector[n_blocks] = block;
3947
3948      ++n_blocks;
3949
3950      /* Record the subblocks, and their subblocks...  */
3951      n_blocks += all_blocks (BLOCK_SUBBLOCKS (block),
3952			      vector ? vector + n_blocks : 0);
3953      block = BLOCK_CHAIN (block);
3954    }
3955
3956  return n_blocks;
3957}
3958
3959/* Return a vector containing all the blocks rooted at BLOCK.  The
3960   number of elements in the vector is stored in N_BLOCKS_P.  The
3961   vector is dynamically allocated; it is the caller's responsibility
3962   to call `free' on the pointer returned.  */
3963
3964static tree *
3965get_block_vector (tree block, int *n_blocks_p)
3966{
3967  tree *block_vector;
3968
3969  *n_blocks_p = all_blocks (block, NULL);
3970  block_vector = XNEWVEC (tree, *n_blocks_p);
3971  all_blocks (block, block_vector);
3972
3973  return block_vector;
3974}
3975
3976static GTY(()) int next_block_index = 2;
3977
3978/* Set BLOCK_NUMBER for all the blocks in FN.  */
3979
3980void
3981number_blocks (tree fn)
3982{
3983  int i;
3984  int n_blocks;
3985  tree *block_vector;
3986
3987  /* For SDB and XCOFF debugging output, we start numbering the blocks
3988     from 1 within each function, rather than keeping a running
3989     count.  */
3990#if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3991  if (write_symbols == SDB_DEBUG || write_symbols == XCOFF_DEBUG)
3992    next_block_index = 1;
3993#endif
3994
3995  block_vector = get_block_vector (DECL_INITIAL (fn), &n_blocks);
3996
3997  /* The top-level BLOCK isn't numbered at all.  */
3998  for (i = 1; i < n_blocks; ++i)
3999    /* We number the blocks from two.  */
4000    BLOCK_NUMBER (block_vector[i]) = next_block_index++;
4001
4002  free (block_vector);
4003
4004  return;
4005}
4006
4007/* If VAR is present in a subblock of BLOCK, return the subblock.  */
4008
4009tree
4010debug_find_var_in_block_tree (tree var, tree block)
4011{
4012  tree t;
4013
4014  for (t = BLOCK_VARS (block); t; t = TREE_CHAIN (t))
4015    if (t == var)
4016      return block;
4017
4018  for (t = BLOCK_SUBBLOCKS (block); t; t = TREE_CHAIN (t))
4019    {
4020      tree ret = debug_find_var_in_block_tree (var, t);
4021      if (ret)
4022	return ret;
4023    }
4024
4025  return NULL_TREE;
4026}
4027
4028/* Keep track of whether we're in a dummy function context.  If we are,
4029   we don't want to invoke the set_current_function hook, because we'll
4030   get into trouble if the hook calls target_reinit () recursively or
4031   when the initial initialization is not yet complete.  */
4032
4033static bool in_dummy_function;
4034
4035/* Invoke the target hook when setting cfun.  Update the optimization options
4036   if the function uses different options than the default.  */
4037
4038static void
4039invoke_set_current_function_hook (tree fndecl)
4040{
4041  if (!in_dummy_function)
4042    {
4043      tree opts = ((fndecl)
4044		   ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl)
4045		   : optimization_default_node);
4046
4047      if (!opts)
4048	opts = optimization_default_node;
4049
4050      /* Change optimization options if needed.  */
4051      if (optimization_current_node != opts)
4052	{
4053	  optimization_current_node = opts;
4054	  cl_optimization_restore (TREE_OPTIMIZATION (opts));
4055	}
4056
4057      targetm.set_current_function (fndecl);
4058    }
4059}
4060
4061/* cfun should never be set directly; use this function.  */
4062
4063void
4064set_cfun (struct function *new_cfun)
4065{
4066  if (cfun != new_cfun)
4067    {
4068      cfun = new_cfun;
4069      invoke_set_current_function_hook (new_cfun ? new_cfun->decl : NULL_TREE);
4070    }
4071}
4072
4073/* Initialized with NOGC, making this poisonous to the garbage collector.  */
4074
4075static VEC(function_p,heap) *cfun_stack;
4076
4077/* Push the current cfun onto the stack, and set cfun to new_cfun.  */
4078
4079void
4080push_cfun (struct function *new_cfun)
4081{
4082  VEC_safe_push (function_p, heap, cfun_stack, cfun);
4083  set_cfun (new_cfun);
4084}
4085
4086/* Pop cfun from the stack.  */
4087
4088void
4089pop_cfun (void)
4090{
4091  struct function *new_cfun = VEC_pop (function_p, cfun_stack);
4092  set_cfun (new_cfun);
4093}
4094
4095/* Return value of funcdef and increase it.  */
4096int
4097get_next_funcdef_no (void)
4098{
4099  return funcdef_no++;
4100}
4101
4102/* Allocate a function structure for FNDECL and set its contents
4103   to the defaults.  Set cfun to the newly-allocated object.
4104   Some of the helper functions invoked during initialization assume
4105   that cfun has already been set.  Therefore, assign the new object
4106   directly into cfun and invoke the back end hook explicitly at the
4107   very end, rather than initializing a temporary and calling set_cfun
4108   on it.
4109
4110   ABSTRACT_P is true if this is a function that will never be seen by
4111   the middle-end.  Such functions are front-end concepts (like C++
4112   function templates) that do not correspond directly to functions
4113   placed in object files.  */
4114
4115void
4116allocate_struct_function (tree fndecl, bool abstract_p)
4117{
4118  tree result;
4119  tree fntype = fndecl ? TREE_TYPE (fndecl) : NULL_TREE;
4120
4121  cfun = GGC_CNEW (struct function);
4122
4123  cfun->function_frequency = FUNCTION_FREQUENCY_NORMAL;
4124
4125  init_eh_for_function ();
4126
4127  if (init_machine_status)
4128    cfun->machine = (*init_machine_status) ();
4129
4130#ifdef OVERRIDE_ABI_FORMAT
4131  OVERRIDE_ABI_FORMAT (fndecl);
4132#endif
4133
4134  invoke_set_current_function_hook (fndecl);
4135
4136  if (fndecl != NULL_TREE)
4137    {
4138      DECL_STRUCT_FUNCTION (fndecl) = cfun;
4139      cfun->decl = fndecl;
4140      current_function_funcdef_no = get_next_funcdef_no ();
4141
4142      result = DECL_RESULT (fndecl);
4143      if (!abstract_p && aggregate_value_p (result, fndecl))
4144	{
4145#ifdef PCC_STATIC_STRUCT_RETURN
4146	  cfun->returns_pcc_struct = 1;
4147#endif
4148	  cfun->returns_struct = 1;
4149	}
4150
4151      cfun->stdarg
4152	= (fntype
4153	   && TYPE_ARG_TYPES (fntype) != 0
4154	   && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype)))
4155	       != void_type_node));
4156
4157      /* Assume all registers in stdarg functions need to be saved.  */
4158      cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE;
4159      cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE;
4160    }
4161}
4162
4163/* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4164   instead of just setting it.  */
4165
4166void
4167push_struct_function (tree fndecl)
4168{
4169  VEC_safe_push (function_p, heap, cfun_stack, cfun);
4170  allocate_struct_function (fndecl, false);
4171}
4172
4173/* Reset cfun, and other non-struct-function variables to defaults as
4174   appropriate for emitting rtl at the start of a function.  */
4175
4176static void
4177prepare_function_start (void)
4178{
4179  gcc_assert (!crtl->emit.x_last_insn);
4180  init_temp_slots ();
4181  init_emit ();
4182  init_varasm_status ();
4183  init_expr ();
4184  default_rtl_profile ();
4185
4186  cse_not_expected = ! optimize;
4187
4188  /* Caller save not needed yet.  */
4189  caller_save_needed = 0;
4190
4191  /* We haven't done register allocation yet.  */
4192  reg_renumber = 0;
4193
4194  /* Indicate that we have not instantiated virtual registers yet.  */
4195  virtuals_instantiated = 0;
4196
4197  /* Indicate that we want CONCATs now.  */
4198  generating_concat_p = 1;
4199
4200  /* Indicate we have no need of a frame pointer yet.  */
4201  frame_pointer_needed = 0;
4202}
4203
4204/* Initialize the rtl expansion mechanism so that we can do simple things
4205   like generate sequences.  This is used to provide a context during global
4206   initialization of some passes.  You must call expand_dummy_function_end
4207   to exit this context.  */
4208
4209void
4210init_dummy_function_start (void)
4211{
4212  gcc_assert (!in_dummy_function);
4213  in_dummy_function = true;
4214  push_struct_function (NULL_TREE);
4215  prepare_function_start ();
4216}
4217
4218/* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4219   and initialize static variables for generating RTL for the statements
4220   of the function.  */
4221
4222void
4223init_function_start (tree subr)
4224{
4225  if (subr && DECL_STRUCT_FUNCTION (subr))
4226    set_cfun (DECL_STRUCT_FUNCTION (subr));
4227  else
4228    allocate_struct_function (subr, false);
4229  prepare_function_start ();
4230
4231  /* Warn if this value is an aggregate type,
4232     regardless of which calling convention we are using for it.  */
4233  if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr))))
4234    warning (OPT_Waggregate_return, "function returns an aggregate");
4235}
4236
4237/* Make sure all values used by the optimization passes have sane defaults.  */
4238unsigned int
4239init_function_for_compilation (void)
4240{
4241  reg_renumber = 0;
4242  return 0;
4243}
4244
4245struct rtl_opt_pass pass_init_function =
4246{
4247 {
4248  RTL_PASS,
4249  "*init_function",                     /* name */
4250  NULL,                                 /* gate */
4251  init_function_for_compilation,        /* execute */
4252  NULL,                                 /* sub */
4253  NULL,                                 /* next */
4254  0,                                    /* static_pass_number */
4255  TV_NONE,                              /* tv_id */
4256  0,                                    /* properties_required */
4257  0,                                    /* properties_provided */
4258  0,                                    /* properties_destroyed */
4259  0,                                    /* todo_flags_start */
4260  0                                     /* todo_flags_finish */
4261 }
4262};
4263
4264
4265void
4266expand_main_function (void)
4267{
4268#if (defined(INVOKE__main)				\
4269     || (!defined(HAS_INIT_SECTION)			\
4270	 && !defined(INIT_SECTION_ASM_OP)		\
4271	 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4272  emit_library_call (init_one_libfunc (NAME__MAIN), LCT_NORMAL, VOIDmode, 0);
4273#endif
4274}
4275
4276/* Expand code to initialize the stack_protect_guard.  This is invoked at
4277   the beginning of a function to be protected.  */
4278
4279#ifndef HAVE_stack_protect_set
4280# define HAVE_stack_protect_set		0
4281# define gen_stack_protect_set(x,y)	(gcc_unreachable (), NULL_RTX)
4282#endif
4283
4284void
4285stack_protect_prologue (void)
4286{
4287  tree guard_decl = targetm.stack_protect_guard ();
4288  rtx x, y;
4289
4290  x = expand_normal (crtl->stack_protect_guard);
4291  y = expand_normal (guard_decl);
4292
4293  /* Allow the target to copy from Y to X without leaking Y into a
4294     register.  */
4295  if (HAVE_stack_protect_set)
4296    {
4297      rtx insn = gen_stack_protect_set (x, y);
4298      if (insn)
4299	{
4300	  emit_insn (insn);
4301	  return;
4302	}
4303    }
4304
4305  /* Otherwise do a straight move.  */
4306  emit_move_insn (x, y);
4307}
4308
4309/* Expand code to verify the stack_protect_guard.  This is invoked at
4310   the end of a function to be protected.  */
4311
4312#ifndef HAVE_stack_protect_test
4313# define HAVE_stack_protect_test		0
4314# define gen_stack_protect_test(x, y, z)	(gcc_unreachable (), NULL_RTX)
4315#endif
4316
4317void
4318stack_protect_epilogue (void)
4319{
4320  tree guard_decl = targetm.stack_protect_guard ();
4321  rtx label = gen_label_rtx ();
4322  rtx x, y, tmp;
4323
4324  x = expand_normal (crtl->stack_protect_guard);
4325  y = expand_normal (guard_decl);
4326
4327  /* Allow the target to compare Y with X without leaking either into
4328     a register.  */
4329  switch (HAVE_stack_protect_test != 0)
4330    {
4331    case 1:
4332      tmp = gen_stack_protect_test (x, y, label);
4333      if (tmp)
4334	{
4335	  emit_insn (tmp);
4336	  break;
4337	}
4338      /* FALLTHRU */
4339
4340    default:
4341      emit_cmp_and_jump_insns (x, y, EQ, NULL_RTX, ptr_mode, 1, label);
4342      break;
4343    }
4344
4345  /* The noreturn predictor has been moved to the tree level.  The rtl-level
4346     predictors estimate this branch about 20%, which isn't enough to get
4347     things moved out of line.  Since this is the only extant case of adding
4348     a noreturn function at the rtl level, it doesn't seem worth doing ought
4349     except adding the prediction by hand.  */
4350  tmp = get_last_insn ();
4351  if (JUMP_P (tmp))
4352    predict_insn_def (tmp, PRED_NORETURN, TAKEN);
4353
4354  expand_expr_stmt (targetm.stack_protect_fail ());
4355  emit_label (label);
4356}
4357
4358/* Start the RTL for a new function, and set variables used for
4359   emitting RTL.
4360   SUBR is the FUNCTION_DECL node.
4361   PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4362   the function's parameters, which must be run at any return statement.  */
4363
4364void
4365expand_function_start (tree subr)
4366{
4367  /* Make sure volatile mem refs aren't considered
4368     valid operands of arithmetic insns.  */
4369  init_recog_no_volatile ();
4370
4371  crtl->profile
4372    = (profile_flag
4373       && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr));
4374
4375  crtl->limit_stack
4376    = (stack_limit_rtx != NULL_RTX && ! DECL_NO_LIMIT_STACK (subr));
4377
4378  /* Make the label for return statements to jump to.  Do not special
4379     case machines with special return instructions -- they will be
4380     handled later during jump, ifcvt, or epilogue creation.  */
4381  return_label = gen_label_rtx ();
4382
4383  /* Initialize rtx used to return the value.  */
4384  /* Do this before assign_parms so that we copy the struct value address
4385     before any library calls that assign parms might generate.  */
4386
4387  /* Decide whether to return the value in memory or in a register.  */
4388  if (aggregate_value_p (DECL_RESULT (subr), subr))
4389    {
4390      /* Returning something that won't go in a register.  */
4391      rtx value_address = 0;
4392
4393#ifdef PCC_STATIC_STRUCT_RETURN
4394      if (cfun->returns_pcc_struct)
4395	{
4396	  int size = int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr)));
4397	  value_address = assemble_static_space (size);
4398	}
4399      else
4400#endif
4401	{
4402	  rtx sv = targetm.calls.struct_value_rtx (TREE_TYPE (subr), 2);
4403	  /* Expect to be passed the address of a place to store the value.
4404	     If it is passed as an argument, assign_parms will take care of
4405	     it.  */
4406	  if (sv)
4407	    {
4408	      value_address = gen_reg_rtx (Pmode);
4409	      emit_move_insn (value_address, sv);
4410	    }
4411	}
4412      if (value_address)
4413	{
4414	  rtx x = value_address;
4415	  if (!DECL_BY_REFERENCE (DECL_RESULT (subr)))
4416	    {
4417	      x = gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr)), x);
4418	      set_mem_attributes (x, DECL_RESULT (subr), 1);
4419	    }
4420	  SET_DECL_RTL (DECL_RESULT (subr), x);
4421	}
4422    }
4423  else if (DECL_MODE (DECL_RESULT (subr)) == VOIDmode)
4424    /* If return mode is void, this decl rtl should not be used.  */
4425    SET_DECL_RTL (DECL_RESULT (subr), NULL_RTX);
4426  else
4427    {
4428      /* Compute the return values into a pseudo reg, which we will copy
4429	 into the true return register after the cleanups are done.  */
4430      tree return_type = TREE_TYPE (DECL_RESULT (subr));
4431      if (TYPE_MODE (return_type) != BLKmode
4432	  && targetm.calls.return_in_msb (return_type))
4433	/* expand_function_end will insert the appropriate padding in
4434	   this case.  Use the return value's natural (unpadded) mode
4435	   within the function proper.  */
4436	SET_DECL_RTL (DECL_RESULT (subr),
4437		      gen_reg_rtx (TYPE_MODE (return_type)));
4438      else
4439	{
4440	  /* In order to figure out what mode to use for the pseudo, we
4441	     figure out what the mode of the eventual return register will
4442	     actually be, and use that.  */
4443	  rtx hard_reg = hard_function_value (return_type, subr, 0, 1);
4444
4445	  /* Structures that are returned in registers are not
4446	     aggregate_value_p, so we may see a PARALLEL or a REG.  */
4447	  if (REG_P (hard_reg))
4448	    SET_DECL_RTL (DECL_RESULT (subr),
4449			  gen_reg_rtx (GET_MODE (hard_reg)));
4450	  else
4451	    {
4452	      gcc_assert (GET_CODE (hard_reg) == PARALLEL);
4453	      SET_DECL_RTL (DECL_RESULT (subr), gen_group_rtx (hard_reg));
4454	    }
4455	}
4456
4457      /* Set DECL_REGISTER flag so that expand_function_end will copy the
4458	 result to the real return register(s).  */
4459      DECL_REGISTER (DECL_RESULT (subr)) = 1;
4460    }
4461
4462  /* Initialize rtx for parameters and local variables.
4463     In some cases this requires emitting insns.  */
4464  assign_parms (subr);
4465
4466  /* If function gets a static chain arg, store it.  */
4467  if (cfun->static_chain_decl)
4468    {
4469      tree parm = cfun->static_chain_decl;
4470      rtx local, chain, insn;
4471
4472      local = gen_reg_rtx (Pmode);
4473      chain = targetm.calls.static_chain (current_function_decl, true);
4474
4475      set_decl_incoming_rtl (parm, chain, false);
4476      SET_DECL_RTL (parm, local);
4477      mark_reg_pointer (local, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm))));
4478
4479      insn = emit_move_insn (local, chain);
4480
4481      /* Mark the register as eliminable, similar to parameters.  */
4482      if (MEM_P (chain)
4483	  && reg_mentioned_p (arg_pointer_rtx, XEXP (chain, 0)))
4484	set_unique_reg_note (insn, REG_EQUIV, chain);
4485    }
4486
4487  /* If the function receives a non-local goto, then store the
4488     bits we need to restore the frame pointer.  */
4489  if (cfun->nonlocal_goto_save_area)
4490    {
4491      tree t_save;
4492      rtx r_save;
4493
4494      /* ??? We need to do this save early.  Unfortunately here is
4495	 before the frame variable gets declared.  Help out...  */
4496      tree var = TREE_OPERAND (cfun->nonlocal_goto_save_area, 0);
4497      if (!DECL_RTL_SET_P (var))
4498	expand_decl (var);
4499
4500      t_save = build4 (ARRAY_REF, ptr_type_node,
4501		       cfun->nonlocal_goto_save_area,
4502		       integer_zero_node, NULL_TREE, NULL_TREE);
4503      r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
4504      r_save = convert_memory_address (Pmode, r_save);
4505
4506      emit_move_insn (r_save, targetm.builtin_setjmp_frame_value ());
4507      update_nonlocal_goto_save_area ();
4508    }
4509
4510  /* The following was moved from init_function_start.
4511     The move is supposed to make sdb output more accurate.  */
4512  /* Indicate the beginning of the function body,
4513     as opposed to parm setup.  */
4514  emit_note (NOTE_INSN_FUNCTION_BEG);
4515
4516  gcc_assert (NOTE_P (get_last_insn ()));
4517
4518  parm_birth_insn = get_last_insn ();
4519
4520  if (crtl->profile)
4521    {
4522#ifdef PROFILE_HOOK
4523      PROFILE_HOOK (current_function_funcdef_no);
4524#endif
4525    }
4526
4527  /* After the display initializations is where the stack checking
4528     probe should go.  */
4529  if(flag_stack_check)
4530    stack_check_probe_note = emit_note (NOTE_INSN_DELETED);
4531
4532  /* Make sure there is a line number after the function entry setup code.  */
4533  force_next_line_note ();
4534}
4535
4536/* Undo the effects of init_dummy_function_start.  */
4537void
4538expand_dummy_function_end (void)
4539{
4540  gcc_assert (in_dummy_function);
4541
4542  /* End any sequences that failed to be closed due to syntax errors.  */
4543  while (in_sequence_p ())
4544    end_sequence ();
4545
4546  /* Outside function body, can't compute type's actual size
4547     until next function's body starts.  */
4548
4549  free_after_parsing (cfun);
4550  free_after_compilation (cfun);
4551  pop_cfun ();
4552  in_dummy_function = false;
4553}
4554
4555/* Call DOIT for each hard register used as a return value from
4556   the current function.  */
4557
4558void
4559diddle_return_value (void (*doit) (rtx, void *), void *arg)
4560{
4561  rtx outgoing = crtl->return_rtx;
4562
4563  if (! outgoing)
4564    return;
4565
4566  if (REG_P (outgoing))
4567    (*doit) (outgoing, arg);
4568  else if (GET_CODE (outgoing) == PARALLEL)
4569    {
4570      int i;
4571
4572      for (i = 0; i < XVECLEN (outgoing, 0); i++)
4573	{
4574	  rtx x = XEXP (XVECEXP (outgoing, 0, i), 0);
4575
4576	  if (REG_P (x) && REGNO (x) < FIRST_PSEUDO_REGISTER)
4577	    (*doit) (x, arg);
4578	}
4579    }
4580}
4581
4582static void
4583do_clobber_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4584{
4585  emit_clobber (reg);
4586}
4587
4588void
4589clobber_return_register (void)
4590{
4591  diddle_return_value (do_clobber_return_reg, NULL);
4592
4593  /* In case we do use pseudo to return value, clobber it too.  */
4594  if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4595    {
4596      tree decl_result = DECL_RESULT (current_function_decl);
4597      rtx decl_rtl = DECL_RTL (decl_result);
4598      if (REG_P (decl_rtl) && REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER)
4599	{
4600	  do_clobber_return_reg (decl_rtl, NULL);
4601	}
4602    }
4603}
4604
4605static void
4606do_use_return_reg (rtx reg, void *arg ATTRIBUTE_UNUSED)
4607{
4608  emit_use (reg);
4609}
4610
4611static void
4612use_return_register (void)
4613{
4614  diddle_return_value (do_use_return_reg, NULL);
4615}
4616
4617/* Possibly warn about unused parameters.  */
4618void
4619do_warn_unused_parameter (tree fn)
4620{
4621  tree decl;
4622
4623  for (decl = DECL_ARGUMENTS (fn);
4624       decl; decl = TREE_CHAIN (decl))
4625    if (!TREE_USED (decl) && TREE_CODE (decl) == PARM_DECL
4626	&& DECL_NAME (decl) && !DECL_ARTIFICIAL (decl)
4627	&& !TREE_NO_WARNING (decl))
4628      warning (OPT_Wunused_parameter, "unused parameter %q+D", decl);
4629}
4630
4631static GTY(()) rtx initial_trampoline;
4632
4633/* Generate RTL for the end of the current function.  */
4634
4635void
4636expand_function_end (void)
4637{
4638  rtx clobber_after;
4639
4640  /* If arg_pointer_save_area was referenced only from a nested
4641     function, we will not have initialized it yet.  Do that now.  */
4642  if (arg_pointer_save_area && ! crtl->arg_pointer_save_area_init)
4643    get_arg_pointer_save_area ();
4644
4645  /* If we are doing generic stack checking and this function makes calls,
4646     do a stack probe at the start of the function to ensure we have enough
4647     space for another stack frame.  */
4648  if (flag_stack_check == GENERIC_STACK_CHECK)
4649    {
4650      rtx insn, seq;
4651
4652      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4653	if (CALL_P (insn))
4654	  {
4655	    rtx max_frame_size = GEN_INT (STACK_CHECK_MAX_FRAME_SIZE);
4656	    start_sequence ();
4657	    if (STACK_CHECK_MOVING_SP)
4658	      anti_adjust_stack_and_probe (max_frame_size, true);
4659	    else
4660	      probe_stack_range (STACK_OLD_CHECK_PROTECT, max_frame_size);
4661	    seq = get_insns ();
4662	    end_sequence ();
4663	    emit_insn_before (seq, stack_check_probe_note);
4664	    break;
4665	  }
4666    }
4667
4668  /* End any sequences that failed to be closed due to syntax errors.  */
4669  while (in_sequence_p ())
4670    end_sequence ();
4671
4672  clear_pending_stack_adjust ();
4673  do_pending_stack_adjust ();
4674
4675  /* Output a linenumber for the end of the function.
4676     SDB depends on this.  */
4677  force_next_line_note ();
4678  set_curr_insn_source_location (input_location);
4679
4680  /* Before the return label (if any), clobber the return
4681     registers so that they are not propagated live to the rest of
4682     the function.  This can only happen with functions that drop
4683     through; if there had been a return statement, there would
4684     have either been a return rtx, or a jump to the return label.
4685
4686     We delay actual code generation after the current_function_value_rtx
4687     is computed.  */
4688  clobber_after = get_last_insn ();
4689
4690  /* Output the label for the actual return from the function.  */
4691  emit_label (return_label);
4692
4693  if (USING_SJLJ_EXCEPTIONS)
4694    {
4695      /* Let except.c know where it should emit the call to unregister
4696	 the function context for sjlj exceptions.  */
4697      if (flag_exceptions)
4698	sjlj_emit_function_exit_after (get_last_insn ());
4699    }
4700  else
4701    {
4702      /* We want to ensure that instructions that may trap are not
4703	 moved into the epilogue by scheduling, because we don't
4704	 always emit unwind information for the epilogue.  */
4705      if (flag_non_call_exceptions)
4706	emit_insn (gen_blockage ());
4707    }
4708
4709  /* If this is an implementation of throw, do what's necessary to
4710     communicate between __builtin_eh_return and the epilogue.  */
4711  expand_eh_return ();
4712
4713  /* If scalar return value was computed in a pseudo-reg, or was a named
4714     return value that got dumped to the stack, copy that to the hard
4715     return register.  */
4716  if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl)))
4717    {
4718      tree decl_result = DECL_RESULT (current_function_decl);
4719      rtx decl_rtl = DECL_RTL (decl_result);
4720
4721      if (REG_P (decl_rtl)
4722	  ? REGNO (decl_rtl) >= FIRST_PSEUDO_REGISTER
4723	  : DECL_REGISTER (decl_result))
4724	{
4725	  rtx real_decl_rtl = crtl->return_rtx;
4726
4727	  /* This should be set in assign_parms.  */
4728	  gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl));
4729
4730	  /* If this is a BLKmode structure being returned in registers,
4731	     then use the mode computed in expand_return.  Note that if
4732	     decl_rtl is memory, then its mode may have been changed,
4733	     but that crtl->return_rtx has not.  */
4734	  if (GET_MODE (real_decl_rtl) == BLKmode)
4735	    PUT_MODE (real_decl_rtl, GET_MODE (decl_rtl));
4736
4737	  /* If a non-BLKmode return value should be padded at the least
4738	     significant end of the register, shift it left by the appropriate
4739	     amount.  BLKmode results are handled using the group load/store
4740	     machinery.  */
4741	  if (TYPE_MODE (TREE_TYPE (decl_result)) != BLKmode
4742	      && targetm.calls.return_in_msb (TREE_TYPE (decl_result)))
4743	    {
4744	      emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl),
4745					   REGNO (real_decl_rtl)),
4746			      decl_rtl);
4747	      shift_return_value (GET_MODE (decl_rtl), true, real_decl_rtl);
4748	    }
4749	  /* If a named return value dumped decl_return to memory, then
4750	     we may need to re-do the PROMOTE_MODE signed/unsigned
4751	     extension.  */
4752	  else if (GET_MODE (real_decl_rtl) != GET_MODE (decl_rtl))
4753	    {
4754	      int unsignedp = TYPE_UNSIGNED (TREE_TYPE (decl_result));
4755	      promote_function_mode (TREE_TYPE (decl_result),
4756				     GET_MODE (decl_rtl), &unsignedp,
4757				     TREE_TYPE (current_function_decl), 1);
4758
4759	      convert_move (real_decl_rtl, decl_rtl, unsignedp);
4760	    }
4761	  else if (GET_CODE (real_decl_rtl) == PARALLEL)
4762	    {
4763	      /* If expand_function_start has created a PARALLEL for decl_rtl,
4764		 move the result to the real return registers.  Otherwise, do
4765		 a group load from decl_rtl for a named return.  */
4766	      if (GET_CODE (decl_rtl) == PARALLEL)
4767		emit_group_move (real_decl_rtl, decl_rtl);
4768	      else
4769		emit_group_load (real_decl_rtl, decl_rtl,
4770				 TREE_TYPE (decl_result),
4771				 int_size_in_bytes (TREE_TYPE (decl_result)));
4772	    }
4773	  /* In the case of complex integer modes smaller than a word, we'll
4774	     need to generate some non-trivial bitfield insertions.  Do that
4775	     on a pseudo and not the hard register.  */
4776	  else if (GET_CODE (decl_rtl) == CONCAT
4777		   && GET_MODE_CLASS (GET_MODE (decl_rtl)) == MODE_COMPLEX_INT
4778		   && GET_MODE_BITSIZE (GET_MODE (decl_rtl)) <= BITS_PER_WORD)
4779	    {
4780	      int old_generating_concat_p;
4781	      rtx tmp;
4782
4783	      old_generating_concat_p = generating_concat_p;
4784	      generating_concat_p = 0;
4785	      tmp = gen_reg_rtx (GET_MODE (decl_rtl));
4786	      generating_concat_p = old_generating_concat_p;
4787
4788	      emit_move_insn (tmp, decl_rtl);
4789	      emit_move_insn (real_decl_rtl, tmp);
4790	    }
4791	  else
4792	    emit_move_insn (real_decl_rtl, decl_rtl);
4793	}
4794    }
4795
4796  /* If returning a structure, arrange to return the address of the value
4797     in a place where debuggers expect to find it.
4798
4799     If returning a structure PCC style,
4800     the caller also depends on this value.
4801     And cfun->returns_pcc_struct is not necessarily set.  */
4802  if (cfun->returns_struct
4803      || cfun->returns_pcc_struct)
4804    {
4805      rtx value_address = DECL_RTL (DECL_RESULT (current_function_decl));
4806      tree type = TREE_TYPE (DECL_RESULT (current_function_decl));
4807      rtx outgoing;
4808
4809      if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl)))
4810	type = TREE_TYPE (type);
4811      else
4812	value_address = XEXP (value_address, 0);
4813
4814      outgoing = targetm.calls.function_value (build_pointer_type (type),
4815					       current_function_decl, true);
4816
4817      /* Mark this as a function return value so integrate will delete the
4818	 assignment and USE below when inlining this function.  */
4819      REG_FUNCTION_VALUE_P (outgoing) = 1;
4820
4821      /* The address may be ptr_mode and OUTGOING may be Pmode.  */
4822      value_address = convert_memory_address (GET_MODE (outgoing),
4823					      value_address);
4824
4825      emit_move_insn (outgoing, value_address);
4826
4827      /* Show return register used to hold result (in this case the address
4828	 of the result.  */
4829      crtl->return_rtx = outgoing;
4830    }
4831
4832  /* Emit the actual code to clobber return register.  */
4833  {
4834    rtx seq;
4835
4836    start_sequence ();
4837    clobber_return_register ();
4838    seq = get_insns ();
4839    end_sequence ();
4840
4841    emit_insn_after (seq, clobber_after);
4842  }
4843
4844  /* Output the label for the naked return from the function.  */
4845  if (naked_return_label)
4846    emit_label (naked_return_label);
4847
4848  /* @@@ This is a kludge.  We want to ensure that instructions that
4849     may trap are not moved into the epilogue by scheduling, because
4850     we don't always emit unwind information for the epilogue.  */
4851  if (! USING_SJLJ_EXCEPTIONS && flag_non_call_exceptions)
4852    emit_insn (gen_blockage ());
4853
4854  /* If stack protection is enabled for this function, check the guard.  */
4855  if (crtl->stack_protect_guard)
4856    stack_protect_epilogue ();
4857
4858  /* If we had calls to alloca, and this machine needs
4859     an accurate stack pointer to exit the function,
4860     insert some code to save and restore the stack pointer.  */
4861  if (! EXIT_IGNORE_STACK
4862      && cfun->calls_alloca)
4863    {
4864      rtx tem = 0;
4865
4866      emit_stack_save (SAVE_FUNCTION, &tem, parm_birth_insn);
4867      emit_stack_restore (SAVE_FUNCTION, tem, NULL_RTX);
4868    }
4869
4870  /* ??? This should no longer be necessary since stupid is no longer with
4871     us, but there are some parts of the compiler (eg reload_combine, and
4872     sh mach_dep_reorg) that still try and compute their own lifetime info
4873     instead of using the general framework.  */
4874  use_return_register ();
4875}
4876
4877rtx
4878get_arg_pointer_save_area (void)
4879{
4880  rtx ret = arg_pointer_save_area;
4881
4882  if (! ret)
4883    {
4884      ret = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0);
4885      arg_pointer_save_area = ret;
4886    }
4887
4888  if (! crtl->arg_pointer_save_area_init)
4889    {
4890      rtx seq;
4891
4892      /* Save the arg pointer at the beginning of the function.  The
4893	 generated stack slot may not be a valid memory address, so we
4894	 have to check it and fix it if necessary.  */
4895      start_sequence ();
4896      emit_move_insn (validize_mem (ret),
4897                      crtl->args.internal_arg_pointer);
4898      seq = get_insns ();
4899      end_sequence ();
4900
4901      push_topmost_sequence ();
4902      emit_insn_after (seq, entry_of_function ());
4903      pop_topmost_sequence ();
4904    }
4905
4906  return ret;
4907}
4908
4909/* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4910   for the first time.  */
4911
4912static void
4913record_insns (rtx insns, rtx end, htab_t *hashp)
4914{
4915  rtx tmp;
4916  htab_t hash = *hashp;
4917
4918  if (hash == NULL)
4919    *hashp = hash
4920      = htab_create_ggc (17, htab_hash_pointer, htab_eq_pointer, NULL);
4921
4922  for (tmp = insns; tmp != end; tmp = NEXT_INSN (tmp))
4923    {
4924      void **slot = htab_find_slot (hash, tmp, INSERT);
4925      gcc_assert (*slot == NULL);
4926      *slot = tmp;
4927    }
4928}
4929
4930/* INSN has been duplicated as COPY, as part of duping a basic block.
4931   If INSN is an epilogue insn, then record COPY as epilogue as well.  */
4932
4933void
4934maybe_copy_epilogue_insn (rtx insn, rtx copy)
4935{
4936  void **slot;
4937
4938  if (epilogue_insn_hash == NULL
4939      || htab_find (epilogue_insn_hash, insn) == NULL)
4940    return;
4941
4942  slot = htab_find_slot (epilogue_insn_hash, copy, INSERT);
4943  gcc_assert (*slot == NULL);
4944  *slot = copy;
4945}
4946
4947/* Set the locator of the insn chain starting at INSN to LOC.  */
4948static void
4949set_insn_locators (rtx insn, int loc)
4950{
4951  while (insn != NULL_RTX)
4952    {
4953      if (INSN_P (insn))
4954	INSN_LOCATOR (insn) = loc;
4955      insn = NEXT_INSN (insn);
4956    }
4957}
4958
4959/* Determine if any INSNs in HASH are, or are part of, INSN.  Because
4960   we can be running after reorg, SEQUENCE rtl is possible.  */
4961
4962static bool
4963contains (const_rtx insn, htab_t hash)
4964{
4965  if (hash == NULL)
4966    return false;
4967
4968  if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
4969    {
4970      int i;
4971      for (i = XVECLEN (PATTERN (insn), 0) - 1; i >= 0; i--)
4972	if (htab_find (hash, XVECEXP (PATTERN (insn), 0, i)))
4973	  return true;
4974      return false;
4975    }
4976
4977  return htab_find (hash, insn) != NULL;
4978}
4979
4980int
4981prologue_epilogue_contains (const_rtx insn)
4982{
4983  if (contains (insn, prologue_insn_hash))
4984    return 1;
4985  if (contains (insn, epilogue_insn_hash))
4986    return 1;
4987  return 0;
4988}
4989
4990#ifdef HAVE_return
4991/* Insert gen_return at the end of block BB.  This also means updating
4992   block_for_insn appropriately.  */
4993
4994static void
4995emit_return_into_block (basic_block bb)
4996{
4997  emit_jump_insn_after (gen_return (), BB_END (bb));
4998}
4999#endif /* HAVE_return */
5000
5001/* Generate the prologue and epilogue RTL if the machine supports it.  Thread
5002   this into place with notes indicating where the prologue ends and where
5003   the epilogue begins.  Update the basic block information when possible.  */
5004
5005static void
5006thread_prologue_and_epilogue_insns (void)
5007{
5008  int inserted = 0;
5009  edge e;
5010#if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5011  rtx seq;
5012#endif
5013#if defined (HAVE_epilogue) || defined(HAVE_return)
5014  rtx epilogue_end = NULL_RTX;
5015#endif
5016  edge_iterator ei;
5017
5018  rtl_profile_for_bb (ENTRY_BLOCK_PTR);
5019#ifdef HAVE_prologue
5020  if (HAVE_prologue)
5021    {
5022      start_sequence ();
5023      seq = gen_prologue ();
5024      emit_insn (seq);
5025
5026      /* Insert an explicit USE for the frame pointer
5027         if the profiling is on and the frame pointer is required.  */
5028      if (crtl->profile && frame_pointer_needed)
5029	emit_use (hard_frame_pointer_rtx);
5030
5031      /* Retain a map of the prologue insns.  */
5032      record_insns (seq, NULL, &prologue_insn_hash);
5033      emit_note (NOTE_INSN_PROLOGUE_END);
5034
5035#ifndef PROFILE_BEFORE_PROLOGUE
5036      /* Ensure that instructions are not moved into the prologue when
5037	 profiling is on.  The call to the profiling routine can be
5038	 emitted within the live range of a call-clobbered register.  */
5039      if (crtl->profile)
5040        emit_insn (gen_blockage ());
5041#endif
5042
5043      seq = get_insns ();
5044      end_sequence ();
5045      set_insn_locators (seq, prologue_locator);
5046
5047      /* Can't deal with multiple successors of the entry block
5048         at the moment.  Function should always have at least one
5049         entry point.  */
5050      gcc_assert (single_succ_p (ENTRY_BLOCK_PTR));
5051
5052      insert_insn_on_edge (seq, single_succ_edge (ENTRY_BLOCK_PTR));
5053      inserted = 1;
5054    }
5055#endif
5056
5057  /* If the exit block has no non-fake predecessors, we don't need
5058     an epilogue.  */
5059  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5060    if ((e->flags & EDGE_FAKE) == 0)
5061      break;
5062  if (e == NULL)
5063    goto epilogue_done;
5064
5065  rtl_profile_for_bb (EXIT_BLOCK_PTR);
5066#ifdef HAVE_return
5067  if (optimize && HAVE_return)
5068    {
5069      /* If we're allowed to generate a simple return instruction,
5070	 then by definition we don't need a full epilogue.  Examine
5071	 the block that falls through to EXIT.   If it does not
5072	 contain any code, examine its predecessors and try to
5073	 emit (conditional) return instructions.  */
5074
5075      basic_block last;
5076      rtx label;
5077
5078      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5079	if (e->flags & EDGE_FALLTHRU)
5080	  break;
5081      if (e == NULL)
5082	goto epilogue_done;
5083      last = e->src;
5084
5085      /* Verify that there are no active instructions in the last block.  */
5086      label = BB_END (last);
5087      while (label && !LABEL_P (label))
5088	{
5089	  if (active_insn_p (label))
5090	    break;
5091	  label = PREV_INSN (label);
5092	}
5093
5094      if (BB_HEAD (last) == label && LABEL_P (label))
5095	{
5096	  edge_iterator ei2;
5097
5098	  for (ei2 = ei_start (last->preds); (e = ei_safe_edge (ei2)); )
5099	    {
5100	      basic_block bb = e->src;
5101	      rtx jump;
5102
5103	      if (bb == ENTRY_BLOCK_PTR)
5104		{
5105		  ei_next (&ei2);
5106		  continue;
5107		}
5108
5109	      jump = BB_END (bb);
5110	      if (!JUMP_P (jump) || JUMP_LABEL (jump) != label)
5111		{
5112		  ei_next (&ei2);
5113		  continue;
5114		}
5115
5116	      /* If we have an unconditional jump, we can replace that
5117		 with a simple return instruction.  */
5118	      if (simplejump_p (jump))
5119		{
5120		  emit_return_into_block (bb);
5121		  delete_insn (jump);
5122		}
5123
5124	      /* If we have a conditional jump, we can try to replace
5125		 that with a conditional return instruction.  */
5126	      else if (condjump_p (jump))
5127		{
5128		  if (! redirect_jump (jump, 0, 0))
5129		    {
5130		      ei_next (&ei2);
5131		      continue;
5132		    }
5133
5134		  /* If this block has only one successor, it both jumps
5135		     and falls through to the fallthru block, so we can't
5136		     delete the edge.  */
5137		  if (single_succ_p (bb))
5138		    {
5139		      ei_next (&ei2);
5140		      continue;
5141		    }
5142		}
5143	      else
5144		{
5145		  ei_next (&ei2);
5146		  continue;
5147		}
5148
5149	      /* Fix up the CFG for the successful change we just made.  */
5150	      redirect_edge_succ (e, EXIT_BLOCK_PTR);
5151	    }
5152
5153	  /* Emit a return insn for the exit fallthru block.  Whether
5154	     this is still reachable will be determined later.  */
5155
5156	  emit_barrier_after (BB_END (last));
5157	  emit_return_into_block (last);
5158	  epilogue_end = BB_END (last);
5159	  single_succ_edge (last)->flags &= ~EDGE_FALLTHRU;
5160	  goto epilogue_done;
5161	}
5162    }
5163#endif
5164
5165  /* A small fib -- epilogue is not yet completed, but we wish to re-use
5166     this marker for the splits of EH_RETURN patterns, and nothing else
5167     uses the flag in the meantime.  */
5168  epilogue_completed = 1;
5169
5170#ifdef HAVE_eh_return
5171  /* Find non-fallthru edges that end with EH_RETURN instructions.  On
5172     some targets, these get split to a special version of the epilogue
5173     code.  In order to be able to properly annotate these with unwind
5174     info, try to split them now.  If we get a valid split, drop an
5175     EPILOGUE_BEG note and mark the insns as epilogue insns.  */
5176  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5177    {
5178      rtx prev, last, trial;
5179
5180      if (e->flags & EDGE_FALLTHRU)
5181	continue;
5182      last = BB_END (e->src);
5183      if (!eh_returnjump_p (last))
5184	continue;
5185
5186      prev = PREV_INSN (last);
5187      trial = try_split (PATTERN (last), last, 1);
5188      if (trial == last)
5189	continue;
5190
5191      record_insns (NEXT_INSN (prev), NEXT_INSN (trial), &epilogue_insn_hash);
5192      emit_note_after (NOTE_INSN_EPILOGUE_BEG, prev);
5193    }
5194#endif
5195
5196  /* Find the edge that falls through to EXIT.  Other edges may exist
5197     due to RETURN instructions, but those don't need epilogues.
5198     There really shouldn't be a mixture -- either all should have
5199     been converted or none, however...  */
5200
5201  FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5202    if (e->flags & EDGE_FALLTHRU)
5203      break;
5204  if (e == NULL)
5205    goto epilogue_done;
5206
5207#ifdef HAVE_epilogue
5208  if (HAVE_epilogue)
5209    {
5210      start_sequence ();
5211      epilogue_end = emit_note (NOTE_INSN_EPILOGUE_BEG);
5212      seq = gen_epilogue ();
5213      emit_jump_insn (seq);
5214
5215      /* Retain a map of the epilogue insns.  */
5216      record_insns (seq, NULL, &epilogue_insn_hash);
5217      set_insn_locators (seq, epilogue_locator);
5218
5219      seq = get_insns ();
5220      end_sequence ();
5221
5222      insert_insn_on_edge (seq, e);
5223      inserted = 1;
5224    }
5225  else
5226#endif
5227    {
5228      basic_block cur_bb;
5229
5230      if (! next_active_insn (BB_END (e->src)))
5231	goto epilogue_done;
5232      /* We have a fall-through edge to the exit block, the source is not
5233         at the end of the function, and there will be an assembler epilogue
5234         at the end of the function.
5235         We can't use force_nonfallthru here, because that would try to
5236         use return.  Inserting a jump 'by hand' is extremely messy, so
5237	 we take advantage of cfg_layout_finalize using
5238	fixup_fallthru_exit_predecessor.  */
5239      cfg_layout_initialize (0);
5240      FOR_EACH_BB (cur_bb)
5241	if (cur_bb->index >= NUM_FIXED_BLOCKS
5242	    && cur_bb->next_bb->index >= NUM_FIXED_BLOCKS)
5243	  cur_bb->aux = cur_bb->next_bb;
5244      cfg_layout_finalize ();
5245    }
5246epilogue_done:
5247  default_rtl_profile ();
5248
5249  if (inserted)
5250    {
5251      commit_edge_insertions ();
5252
5253      /* The epilogue insns we inserted may cause the exit edge to no longer
5254	 be fallthru.  */
5255      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5256	{
5257	  if (((e->flags & EDGE_FALLTHRU) != 0)
5258	      && returnjump_p (BB_END (e->src)))
5259	    e->flags &= ~EDGE_FALLTHRU;
5260	}
5261    }
5262
5263#ifdef HAVE_sibcall_epilogue
5264  /* Emit sibling epilogues before any sibling call sites.  */
5265  for (ei = ei_start (EXIT_BLOCK_PTR->preds); (e = ei_safe_edge (ei)); )
5266    {
5267      basic_block bb = e->src;
5268      rtx insn = BB_END (bb);
5269
5270      if (!CALL_P (insn)
5271	  || ! SIBLING_CALL_P (insn))
5272	{
5273	  ei_next (&ei);
5274	  continue;
5275	}
5276
5277      start_sequence ();
5278      emit_note (NOTE_INSN_EPILOGUE_BEG);
5279      emit_insn (gen_sibcall_epilogue ());
5280      seq = get_insns ();
5281      end_sequence ();
5282
5283      /* Retain a map of the epilogue insns.  Used in life analysis to
5284	 avoid getting rid of sibcall epilogue insns.  Do this before we
5285	 actually emit the sequence.  */
5286      record_insns (seq, NULL, &epilogue_insn_hash);
5287      set_insn_locators (seq, epilogue_locator);
5288
5289      emit_insn_before (seq, insn);
5290      ei_next (&ei);
5291    }
5292#endif
5293
5294#ifdef HAVE_epilogue
5295  if (epilogue_end)
5296    {
5297      rtx insn, next;
5298
5299      /* Similarly, move any line notes that appear after the epilogue.
5300         There is no need, however, to be quite so anal about the existence
5301	 of such a note.  Also possibly move
5302	 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5303	 info generation.  */
5304      for (insn = epilogue_end; insn; insn = next)
5305	{
5306	  next = NEXT_INSN (insn);
5307	  if (NOTE_P (insn)
5308	      && (NOTE_KIND (insn) == NOTE_INSN_FUNCTION_BEG))
5309	    reorder_insns (insn, insn, PREV_INSN (epilogue_end));
5310	}
5311    }
5312#endif
5313
5314  /* Threading the prologue and epilogue changes the artificial refs
5315     in the entry and exit blocks.  */
5316  epilogue_completed = 1;
5317  df_update_entry_exit_and_calls ();
5318}
5319
5320/* Reposition the prologue-end and epilogue-begin notes after
5321   instruction scheduling.  */
5322
5323void
5324reposition_prologue_and_epilogue_notes (void)
5325{
5326#if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5327    || defined (HAVE_sibcall_epilogue)
5328  /* Since the hash table is created on demand, the fact that it is
5329     non-null is a signal that it is non-empty.  */
5330  if (prologue_insn_hash != NULL)
5331    {
5332      size_t len = htab_elements (prologue_insn_hash);
5333      rtx insn, last = NULL, note = NULL;
5334
5335      /* Scan from the beginning until we reach the last prologue insn.  */
5336      /* ??? While we do have the CFG intact, there are two problems:
5337	 (1) The prologue can contain loops (typically probing the stack),
5338	     which means that the end of the prologue isn't in the first bb.
5339	 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb.  */
5340      for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
5341	{
5342	  if (NOTE_P (insn))
5343	    {
5344	      if (NOTE_KIND (insn) == NOTE_INSN_PROLOGUE_END)
5345		note = insn;
5346	    }
5347	  else if (contains (insn, prologue_insn_hash))
5348	    {
5349	      last = insn;
5350	      if (--len == 0)
5351		break;
5352	    }
5353	}
5354
5355      if (last)
5356	{
5357	  if (note == NULL)
5358	    {
5359	      /* Scan forward looking for the PROLOGUE_END note.  It should
5360		 be right at the beginning of the block, possibly with other
5361		 insn notes that got moved there.  */
5362	      for (note = NEXT_INSN (last); ; note = NEXT_INSN (note))
5363		{
5364		  if (NOTE_P (note)
5365		      && NOTE_KIND (note) == NOTE_INSN_PROLOGUE_END)
5366		    break;
5367		}
5368	    }
5369
5370	  /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note.  */
5371	  if (LABEL_P (last))
5372	    last = NEXT_INSN (last);
5373	  reorder_insns (note, note, last);
5374	}
5375    }
5376
5377  if (epilogue_insn_hash != NULL)
5378    {
5379      edge_iterator ei;
5380      edge e;
5381
5382      FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR->preds)
5383	{
5384	  rtx insn, first = NULL, note = NULL;
5385	  basic_block bb = e->src;
5386
5387	  /* Scan from the beginning until we reach the first epilogue insn. */
5388	  FOR_BB_INSNS (bb, insn)
5389	    {
5390	      if (NOTE_P (insn))
5391		{
5392		  if (NOTE_KIND (insn) == NOTE_INSN_EPILOGUE_BEG)
5393		    {
5394		      note = insn;
5395		      if (first != NULL)
5396			break;
5397		    }
5398		}
5399	      else if (first == NULL && contains (insn, epilogue_insn_hash))
5400		{
5401		  first = insn;
5402		  if (note != NULL)
5403		    break;
5404		}
5405	    }
5406
5407	  if (note)
5408	    {
5409	      /* If the function has a single basic block, and no real
5410		 epilogue insns (e.g. sibcall with no cleanup), the
5411		 epilogue note can get scheduled before the prologue
5412		 note.  If we have frame related prologue insns, having
5413		 them scanned during the epilogue will result in a crash.
5414		 In this case re-order the epilogue note to just before
5415		 the last insn in the block.  */
5416	      if (first == NULL)
5417		first = BB_END (bb);
5418
5419	      if (PREV_INSN (first) != note)
5420		reorder_insns (note, note, PREV_INSN (first));
5421	    }
5422	}
5423    }
5424#endif /* HAVE_prologue or HAVE_epilogue */
5425}
5426
5427/* Returns the name of the current function.  */
5428const char *
5429current_function_name (void)
5430{
5431  if (cfun == NULL)
5432    return "<none>";
5433  return lang_hooks.decl_printable_name (cfun->decl, 2);
5434}
5435
5436
5437static unsigned int
5438rest_of_handle_check_leaf_regs (void)
5439{
5440#ifdef LEAF_REGISTERS
5441  current_function_uses_only_leaf_regs
5442    = optimize > 0 && only_leaf_regs_used () && leaf_function_p ();
5443#endif
5444  return 0;
5445}
5446
5447/* Insert a TYPE into the used types hash table of CFUN.  */
5448
5449static void
5450used_types_insert_helper (tree type, struct function *func)
5451{
5452  if (type != NULL && func != NULL)
5453    {
5454      void **slot;
5455
5456      if (func->used_types_hash == NULL)
5457	func->used_types_hash = htab_create_ggc (37, htab_hash_pointer,
5458						 htab_eq_pointer, NULL);
5459      slot = htab_find_slot (func->used_types_hash, type, INSERT);
5460      if (*slot == NULL)
5461	*slot = type;
5462    }
5463}
5464
5465/* Given a type, insert it into the used hash table in cfun.  */
5466void
5467used_types_insert (tree t)
5468{
5469  while (POINTER_TYPE_P (t) || TREE_CODE (t) == ARRAY_TYPE)
5470    if (TYPE_NAME (t))
5471      break;
5472    else
5473      t = TREE_TYPE (t);
5474  if (TYPE_NAME (t) == NULL_TREE
5475      || TYPE_NAME (t) == TYPE_NAME (TYPE_MAIN_VARIANT (t)))
5476    t = TYPE_MAIN_VARIANT (t);
5477  if (debug_info_level > DINFO_LEVEL_NONE)
5478    {
5479      if (cfun)
5480	used_types_insert_helper (t, cfun);
5481      else
5482	/* So this might be a type referenced by a global variable.
5483	   Record that type so that we can later decide to emit its debug
5484	   information.  */
5485	types_used_by_cur_var_decl =
5486	  tree_cons (t, NULL, types_used_by_cur_var_decl);
5487
5488    }
5489}
5490
5491/* Helper to Hash a struct types_used_by_vars_entry.  */
5492
5493static hashval_t
5494hash_types_used_by_vars_entry (const struct types_used_by_vars_entry *entry)
5495{
5496  gcc_assert (entry && entry->var_decl && entry->type);
5497
5498  return iterative_hash_object (entry->type,
5499				iterative_hash_object (entry->var_decl, 0));
5500}
5501
5502/* Hash function of the types_used_by_vars_entry hash table.  */
5503
5504hashval_t
5505types_used_by_vars_do_hash (const void *x)
5506{
5507  const struct types_used_by_vars_entry *entry =
5508    (const struct types_used_by_vars_entry *) x;
5509
5510  return hash_types_used_by_vars_entry (entry);
5511}
5512
5513/*Equality function of the types_used_by_vars_entry hash table.  */
5514
5515int
5516types_used_by_vars_eq (const void *x1, const void *x2)
5517{
5518  const struct types_used_by_vars_entry *e1 =
5519    (const struct types_used_by_vars_entry *) x1;
5520  const struct types_used_by_vars_entry *e2 =
5521    (const struct types_used_by_vars_entry *)x2;
5522
5523  return (e1->var_decl == e2->var_decl && e1->type == e2->type);
5524}
5525
5526/* Inserts an entry into the types_used_by_vars_hash hash table. */
5527
5528void
5529types_used_by_var_decl_insert (tree type, tree var_decl)
5530{
5531  if (type != NULL && var_decl != NULL)
5532    {
5533      void **slot;
5534      struct types_used_by_vars_entry e;
5535      e.var_decl = var_decl;
5536      e.type = type;
5537      if (types_used_by_vars_hash == NULL)
5538	types_used_by_vars_hash =
5539	  htab_create_ggc (37, types_used_by_vars_do_hash,
5540			   types_used_by_vars_eq, NULL);
5541      slot = htab_find_slot_with_hash (types_used_by_vars_hash, &e,
5542				       hash_types_used_by_vars_entry (&e), INSERT);
5543      if (*slot == NULL)
5544	{
5545	  struct types_used_by_vars_entry *entry;
5546	  entry = (struct types_used_by_vars_entry*) ggc_alloc
5547		    (sizeof (struct types_used_by_vars_entry));
5548	  entry->type = type;
5549	  entry->var_decl = var_decl;
5550	  *slot = entry;
5551	}
5552    }
5553}
5554
5555struct rtl_opt_pass pass_leaf_regs =
5556{
5557 {
5558  RTL_PASS,
5559  "*leaf_regs",                         /* name */
5560  NULL,                                 /* gate */
5561  rest_of_handle_check_leaf_regs,       /* execute */
5562  NULL,                                 /* sub */
5563  NULL,                                 /* next */
5564  0,                                    /* static_pass_number */
5565  TV_NONE,                              /* tv_id */
5566  0,                                    /* properties_required */
5567  0,                                    /* properties_provided */
5568  0,                                    /* properties_destroyed */
5569  0,                                    /* todo_flags_start */
5570  0                                     /* todo_flags_finish */
5571 }
5572};
5573
5574static unsigned int
5575rest_of_handle_thread_prologue_and_epilogue (void)
5576{
5577  if (optimize)
5578    cleanup_cfg (CLEANUP_EXPENSIVE);
5579  /* On some machines, the prologue and epilogue code, or parts thereof,
5580     can be represented as RTL.  Doing so lets us schedule insns between
5581     it and the rest of the code and also allows delayed branch
5582     scheduling to operate in the epilogue.  */
5583
5584  thread_prologue_and_epilogue_insns ();
5585  return 0;
5586}
5587
5588struct rtl_opt_pass pass_thread_prologue_and_epilogue =
5589{
5590 {
5591  RTL_PASS,
5592  "pro_and_epilogue",                   /* name */
5593  NULL,                                 /* gate */
5594  rest_of_handle_thread_prologue_and_epilogue, /* execute */
5595  NULL,                                 /* sub */
5596  NULL,                                 /* next */
5597  0,                                    /* static_pass_number */
5598  TV_THREAD_PROLOGUE_AND_EPILOGUE,      /* tv_id */
5599  0,                                    /* properties_required */
5600  0,                                    /* properties_provided */
5601  0,                                    /* properties_destroyed */
5602  TODO_verify_flow,                     /* todo_flags_start */
5603  TODO_dump_func |
5604  TODO_df_verify |
5605  TODO_df_finish | TODO_verify_rtl_sharing |
5606  TODO_ggc_collect                      /* todo_flags_finish */
5607 }
5608};
5609
5610
5611/* This mini-pass fixes fall-out from SSA in asm statements that have
5612   in-out constraints.  Say you start with
5613
5614     orig = inout;
5615     asm ("": "+mr" (inout));
5616     use (orig);
5617
5618   which is transformed very early to use explicit output and match operands:
5619
5620     orig = inout;
5621     asm ("": "=mr" (inout) : "0" (inout));
5622     use (orig);
5623
5624   Or, after SSA and copyprop,
5625
5626     asm ("": "=mr" (inout_2) : "0" (inout_1));
5627     use (inout_1);
5628
5629   Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5630   they represent two separate values, so they will get different pseudo
5631   registers during expansion.  Then, since the two operands need to match
5632   per the constraints, but use different pseudo registers, reload can
5633   only register a reload for these operands.  But reloads can only be
5634   satisfied by hardregs, not by memory, so we need a register for this
5635   reload, just because we are presented with non-matching operands.
5636   So, even though we allow memory for this operand, no memory can be
5637   used for it, just because the two operands don't match.  This can
5638   cause reload failures on register-starved targets.
5639
5640   So it's a symptom of reload not being able to use memory for reloads
5641   or, alternatively it's also a symptom of both operands not coming into
5642   reload as matching (in which case the pseudo could go to memory just
5643   fine, as the alternative allows it, and no reload would be necessary).
5644   We fix the latter problem here, by transforming
5645
5646     asm ("": "=mr" (inout_2) : "0" (inout_1));
5647
5648   back to
5649
5650     inout_2 = inout_1;
5651     asm ("": "=mr" (inout_2) : "0" (inout_2));  */
5652
5653static void
5654match_asm_constraints_1 (rtx insn, rtx *p_sets, int noutputs)
5655{
5656  int i;
5657  bool changed = false;
5658  rtx op = SET_SRC (p_sets[0]);
5659  int ninputs = ASM_OPERANDS_INPUT_LENGTH (op);
5660  rtvec inputs = ASM_OPERANDS_INPUT_VEC (op);
5661  bool *output_matched = XALLOCAVEC (bool, noutputs);
5662
5663  memset (output_matched, 0, noutputs * sizeof (bool));
5664  for (i = 0; i < ninputs; i++)
5665    {
5666      rtx input, output, insns;
5667      const char *constraint = ASM_OPERANDS_INPUT_CONSTRAINT (op, i);
5668      char *end;
5669      int match, j;
5670
5671      if (*constraint == '%')
5672	constraint++;
5673
5674      match = strtoul (constraint, &end, 10);
5675      if (end == constraint)
5676	continue;
5677
5678      gcc_assert (match < noutputs);
5679      output = SET_DEST (p_sets[match]);
5680      input = RTVEC_ELT (inputs, i);
5681      /* Only do the transformation for pseudos.  */
5682      if (! REG_P (output)
5683	  || rtx_equal_p (output, input)
5684	  || (GET_MODE (input) != VOIDmode
5685	      && GET_MODE (input) != GET_MODE (output)))
5686	continue;
5687
5688      /* We can't do anything if the output is also used as input,
5689	 as we're going to overwrite it.  */
5690      for (j = 0; j < ninputs; j++)
5691        if (reg_overlap_mentioned_p (output, RTVEC_ELT (inputs, j)))
5692	  break;
5693      if (j != ninputs)
5694	continue;
5695
5696      /* Avoid changing the same input several times.  For
5697	 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5698	 only change in once (to out1), rather than changing it
5699	 first to out1 and afterwards to out2.  */
5700      if (i > 0)
5701	{
5702	  for (j = 0; j < noutputs; j++)
5703	    if (output_matched[j] && input == SET_DEST (p_sets[j]))
5704	      break;
5705	  if (j != noutputs)
5706	    continue;
5707	}
5708      output_matched[match] = true;
5709
5710      start_sequence ();
5711      emit_move_insn (output, input);
5712      insns = get_insns ();
5713      end_sequence ();
5714      emit_insn_before (insns, insn);
5715
5716      /* Now replace all mentions of the input with output.  We can't
5717	 just replace the occurrence in inputs[i], as the register might
5718	 also be used in some other input (or even in an address of an
5719	 output), which would mean possibly increasing the number of
5720	 inputs by one (namely 'output' in addition), which might pose
5721	 a too complicated problem for reload to solve.  E.g. this situation:
5722
5723	   asm ("" : "=r" (output), "=m" (input) : "0" (input))
5724
5725	 Here 'input' is used in two occurrences as input (once for the
5726	 input operand, once for the address in the second output operand).
5727	 If we would replace only the occurrence of the input operand (to
5728	 make the matching) we would be left with this:
5729
5730	   output = input
5731	   asm ("" : "=r" (output), "=m" (input) : "0" (output))
5732
5733	 Now we suddenly have two different input values (containing the same
5734	 value, but different pseudos) where we formerly had only one.
5735	 With more complicated asms this might lead to reload failures
5736	 which wouldn't have happen without this pass.  So, iterate over
5737	 all operands and replace all occurrences of the register used.  */
5738      for (j = 0; j < noutputs; j++)
5739	if (!rtx_equal_p (SET_DEST (p_sets[j]), input)
5740	    && reg_overlap_mentioned_p (input, SET_DEST (p_sets[j])))
5741	  SET_DEST (p_sets[j]) = replace_rtx (SET_DEST (p_sets[j]),
5742					      input, output);
5743      for (j = 0; j < ninputs; j++)
5744	if (reg_overlap_mentioned_p (input, RTVEC_ELT (inputs, j)))
5745	  RTVEC_ELT (inputs, j) = replace_rtx (RTVEC_ELT (inputs, j),
5746					       input, output);
5747
5748      changed = true;
5749    }
5750
5751  if (changed)
5752    df_insn_rescan (insn);
5753}
5754
5755static unsigned
5756rest_of_match_asm_constraints (void)
5757{
5758  basic_block bb;
5759  rtx insn, pat, *p_sets;
5760  int noutputs;
5761
5762  if (!crtl->has_asm_statement)
5763    return 0;
5764
5765  df_set_flags (DF_DEFER_INSN_RESCAN);
5766  FOR_EACH_BB (bb)
5767    {
5768      FOR_BB_INSNS (bb, insn)
5769	{
5770	  if (!INSN_P (insn))
5771	    continue;
5772
5773	  pat = PATTERN (insn);
5774	  if (GET_CODE (pat) == PARALLEL)
5775	    p_sets = &XVECEXP (pat, 0, 0), noutputs = XVECLEN (pat, 0);
5776	  else if (GET_CODE (pat) == SET)
5777	    p_sets = &PATTERN (insn), noutputs = 1;
5778	  else
5779	    continue;
5780
5781	  if (GET_CODE (*p_sets) == SET
5782	      && GET_CODE (SET_SRC (*p_sets)) == ASM_OPERANDS)
5783	    match_asm_constraints_1 (insn, p_sets, noutputs);
5784	 }
5785    }
5786
5787  return TODO_df_finish;
5788}
5789
5790struct rtl_opt_pass pass_match_asm_constraints =
5791{
5792 {
5793  RTL_PASS,
5794  "asmcons",				/* name */
5795  NULL,					/* gate */
5796  rest_of_match_asm_constraints,	/* execute */
5797  NULL,                                 /* sub */
5798  NULL,                                 /* next */
5799  0,                                    /* static_pass_number */
5800  TV_NONE,				/* tv_id */
5801  0,                                    /* properties_required */
5802  0,                                    /* properties_provided */
5803  0,                                    /* properties_destroyed */
5804  0,					/* todo_flags_start */
5805  TODO_dump_func                       /* todo_flags_finish */
5806 }
5807};
5808
5809
5810#include "gt-function.h"
5811