1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2021 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
20 /* This file handles the generation of rtl code from tree structure
21 at the level of the function as a whole.
22 It creates the rtl expressions for parameters and auto variables
23 and has full responsibility for allocating stack slots.
25 `expand_function_start' is called at the beginning of a function,
26 before the function body is parsed, and `expand_function_end' is
27 called after parsing the body.
29 Call `assign_stack_local' to allocate a stack slot for a local variable.
30 This is usually done during the RTL generation for the function body,
31 but it can also be done in the reload pass when a pseudo-register does
32 not get a hard register. */
36 #include "coretypes.h"
41 #include "gimple-expr.h"
46 #include "stringpool.h"
53 #include "rtl-error.h"
54 #include "hard-reg-set.h"
56 #include "fold-const.h"
57 #include "stor-layout.h"
64 #include "optabs-tree.h"
66 #include "langhooks.h"
67 #include "common/common-target.h"
69 #include "tree-pass.h"
73 #include "cfgcleanup.h"
74 #include "cfgexpand.h"
75 #include "shrink-wrap.h"
80 #include "stringpool.h"
84 #include "function-abi.h"
86 /* So we can assign to cfun in this file. */
89 #ifndef STACK_ALIGNMENT_NEEDED
90 #define STACK_ALIGNMENT_NEEDED 1
93 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
95 /* Round a value to the lowest integer less than it that is a multiple of
96 the required alignment. Avoid using division in case the value is
97 negative. Assume the alignment is a power of two. */
98 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
100 /* Similar, but round to the next highest integer that meets the
102 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
104 /* Nonzero once virtual register instantiation has been done.
105 assign_stack_local uses frame_pointer_rtx when this is nonzero.
106 calls.c:emit_library_call_value_1 uses it to set up
107 post-instantiation libcalls. */
108 int virtuals_instantiated
;
110 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
111 static GTY(()) int funcdef_no
;
113 /* These variables hold pointers to functions to create and destroy
114 target specific, per-function data structures. */
115 struct machine_function
* (*init_machine_status
) (void);
117 /* The currently compiled function. */
118 struct function
*cfun
= 0;
120 /* These hashes record the prologue and epilogue insns. */
122 struct insn_cache_hasher
: ggc_cache_ptr_hash
<rtx_def
>
124 static hashval_t
hash (rtx x
) { return htab_hash_pointer (x
); }
125 static bool equal (rtx a
, rtx b
) { return a
== b
; }
129 hash_table
<insn_cache_hasher
> *prologue_insn_hash
;
131 hash_table
<insn_cache_hasher
> *epilogue_insn_hash
;
134 hash_table
<used_type_hasher
> *types_used_by_vars_hash
= NULL
;
135 vec
<tree
, va_gc
> *types_used_by_cur_var_decl
;
137 /* Forward declarations. */
139 static class temp_slot
*find_temp_slot_from_address (rtx
);
140 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
141 static void pad_below (struct args_size
*, machine_mode
, tree
);
142 static void reorder_blocks_1 (rtx_insn
*, tree
, vec
<tree
> *);
143 static int all_blocks (tree
, tree
*);
144 static tree
*get_block_vector (tree
, int *);
145 extern tree
debug_find_var_in_block_tree (tree
, tree
);
146 /* We always define `record_insns' even if it's not used so that we
147 can always export `prologue_epilogue_contains'. */
148 static void record_insns (rtx_insn
*, rtx
, hash_table
<insn_cache_hasher
> **)
150 static bool contains (const rtx_insn
*, hash_table
<insn_cache_hasher
> *);
151 static void prepare_function_start (void);
152 static void do_clobber_return_reg (rtx
, void *);
153 static void do_use_return_reg (rtx
, void *);
156 /* Stack of nested functions. */
157 /* Keep track of the cfun stack. */
159 static vec
<function
*> function_context_stack
;
161 /* Save the current context for compilation of a nested function.
162 This is called from language-specific code. */
165 push_function_context (void)
168 allocate_struct_function (NULL
, false);
170 function_context_stack
.safe_push (cfun
);
174 /* Restore the last saved context, at the end of a nested function.
175 This function is called from language-specific code. */
178 pop_function_context (void)
180 struct function
*p
= function_context_stack
.pop ();
182 current_function_decl
= p
->decl
;
184 /* Reset variables that have known state during rtx generation. */
185 virtuals_instantiated
= 0;
186 generating_concat_p
= 1;
189 /* Clear out all parts of the state in F that can safely be discarded
190 after the function has been parsed, but not compiled, to let
191 garbage collection reclaim the memory. */
194 free_after_parsing (struct function
*f
)
199 /* Clear out all parts of the state in F that can safely be discarded
200 after the function has been compiled, to let garbage collection
201 reclaim the memory. */
204 free_after_compilation (struct function
*f
)
206 prologue_insn_hash
= NULL
;
207 epilogue_insn_hash
= NULL
;
209 free (crtl
->emit
.regno_pointer_align
);
211 memset (crtl
, 0, sizeof (struct rtl_data
));
215 f
->curr_properties
&= ~PROP_cfg
;
217 regno_reg_rtx
= NULL
;
220 /* Return size needed for stack frame based on slots so far allocated.
221 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
222 the caller may have to do that. */
225 get_frame_size (void)
227 if (FRAME_GROWS_DOWNWARD
)
228 return -frame_offset
;
233 /* Issue an error message and return TRUE if frame OFFSET overflows in
234 the signed target pointer arithmetics for function FUNC. Otherwise
238 frame_offset_overflow (poly_int64 offset
, tree func
)
240 poly_uint64 size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
241 unsigned HOST_WIDE_INT limit
242 = ((HOST_WIDE_INT_1U
<< (GET_MODE_BITSIZE (Pmode
) - 1))
243 /* Leave room for the fixed part of the frame. */
244 - 64 * UNITS_PER_WORD
);
246 if (!coeffs_in_range_p (size
, 0U, limit
))
248 unsigned HOST_WIDE_INT hwisize
;
249 if (size
.is_constant (&hwisize
))
250 error_at (DECL_SOURCE_LOCATION (func
),
251 "total size of local objects %wu exceeds maximum %wu",
254 error_at (DECL_SOURCE_LOCATION (func
),
255 "total size of local objects exceeds maximum %wu",
263 /* Return the minimum spill slot alignment for a register of mode MODE. */
266 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED
)
268 return STACK_SLOT_ALIGNMENT (NULL_TREE
, mode
, GET_MODE_ALIGNMENT (mode
));
271 /* Return stack slot alignment in bits for TYPE and MODE. */
274 get_stack_local_alignment (tree type
, machine_mode mode
)
276 unsigned int alignment
;
279 alignment
= BIGGEST_ALIGNMENT
;
281 alignment
= GET_MODE_ALIGNMENT (mode
);
283 /* Allow the frond-end to (possibly) increase the alignment of this
286 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
288 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
291 /* Determine whether it is possible to fit a stack slot of size SIZE and
292 alignment ALIGNMENT into an area in the stack frame that starts at
293 frame offset START and has a length of LENGTH. If so, store the frame
294 offset to be used for the stack slot in *POFFSET and return true;
295 return false otherwise. This function will extend the frame size when
296 given a start/length pair that lies at the end of the frame. */
299 try_fit_stack_local (poly_int64 start
, poly_int64 length
,
300 poly_int64 size
, unsigned int alignment
,
301 poly_int64_pod
*poffset
)
303 poly_int64 this_frame_offset
;
304 int frame_off
, frame_alignment
, frame_phase
;
306 /* Calculate how many bytes the start of local variables is off from
308 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
309 frame_off
= targetm
.starting_frame_offset () % frame_alignment
;
310 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
312 /* Round the frame offset to the specified alignment. */
314 if (FRAME_GROWS_DOWNWARD
)
316 = (aligned_lower_bound (start
+ length
- size
- frame_phase
, alignment
)
320 = aligned_upper_bound (start
- frame_phase
, alignment
) + frame_phase
;
322 /* See if it fits. If this space is at the edge of the frame,
323 consider extending the frame to make it fit. Our caller relies on
324 this when allocating a new slot. */
325 if (maybe_lt (this_frame_offset
, start
))
327 if (known_eq (frame_offset
, start
))
328 frame_offset
= this_frame_offset
;
332 else if (maybe_gt (this_frame_offset
+ size
, start
+ length
))
334 if (known_eq (frame_offset
, start
+ length
))
335 frame_offset
= this_frame_offset
+ size
;
340 *poffset
= this_frame_offset
;
344 /* Create a new frame_space structure describing free space in the stack
345 frame beginning at START and ending at END, and chain it into the
346 function's frame_space_list. */
349 add_frame_space (poly_int64 start
, poly_int64 end
)
351 class frame_space
*space
= ggc_alloc
<frame_space
> ();
352 space
->next
= crtl
->frame_space_list
;
353 crtl
->frame_space_list
= space
;
354 space
->start
= start
;
355 space
->length
= end
- start
;
358 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
359 with machine mode MODE.
361 ALIGN controls the amount of alignment for the address of the slot:
362 0 means according to MODE,
363 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
364 -2 means use BITS_PER_UNIT,
365 positive specifies alignment boundary in bits.
367 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
368 alignment and ASLK_RECORD_PAD bit set if we should remember
369 extra space we allocated for alignment purposes. When we are
370 called from assign_stack_temp_for_type, it is not set so we don't
371 track the same stack slot in two independent lists.
373 We do not round to stack_boundary here. */
376 assign_stack_local_1 (machine_mode mode
, poly_int64 size
,
380 poly_int64 bigend_correction
= 0;
381 poly_int64 slot_offset
= 0, old_frame_offset
;
382 unsigned int alignment
, alignment_in_bits
;
386 alignment
= get_stack_local_alignment (NULL
, mode
);
387 alignment
/= BITS_PER_UNIT
;
389 else if (align
== -1)
391 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
392 size
= aligned_upper_bound (size
, alignment
);
394 else if (align
== -2)
395 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
397 alignment
= align
/ BITS_PER_UNIT
;
399 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
401 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
402 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
404 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
405 alignment
= MAX_SUPPORTED_STACK_ALIGNMENT
/ BITS_PER_UNIT
;
408 if (SUPPORTS_STACK_ALIGNMENT
)
410 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
412 if (!crtl
->stack_realign_processed
)
413 crtl
->stack_alignment_estimated
= alignment_in_bits
;
416 /* If stack is realigned and stack alignment value
417 hasn't been finalized, it is OK not to increase
418 stack_alignment_estimated. The bigger alignment
419 requirement is recorded in stack_alignment_needed
421 gcc_assert (!crtl
->stack_realign_finalized
);
422 if (!crtl
->stack_realign_needed
)
424 /* It is OK to reduce the alignment as long as the
425 requested size is 0 or the estimated stack
426 alignment >= mode alignment. */
427 gcc_assert ((kind
& ASLK_REDUCE_ALIGN
)
428 || known_eq (size
, 0)
429 || (crtl
->stack_alignment_estimated
430 >= GET_MODE_ALIGNMENT (mode
)));
431 alignment_in_bits
= crtl
->stack_alignment_estimated
;
432 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
438 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
439 crtl
->stack_alignment_needed
= alignment_in_bits
;
440 if (crtl
->max_used_stack_slot_alignment
< alignment_in_bits
)
441 crtl
->max_used_stack_slot_alignment
= alignment_in_bits
;
443 if (mode
!= BLKmode
|| maybe_ne (size
, 0))
445 if (kind
& ASLK_RECORD_PAD
)
447 class frame_space
**psp
;
449 for (psp
= &crtl
->frame_space_list
; *psp
; psp
= &(*psp
)->next
)
451 class frame_space
*space
= *psp
;
452 if (!try_fit_stack_local (space
->start
, space
->length
, size
,
453 alignment
, &slot_offset
))
456 if (known_gt (slot_offset
, space
->start
))
457 add_frame_space (space
->start
, slot_offset
);
458 if (known_lt (slot_offset
+ size
, space
->start
+ space
->length
))
459 add_frame_space (slot_offset
+ size
,
460 space
->start
+ space
->length
);
465 else if (!STACK_ALIGNMENT_NEEDED
)
467 slot_offset
= frame_offset
;
471 old_frame_offset
= frame_offset
;
473 if (FRAME_GROWS_DOWNWARD
)
475 frame_offset
-= size
;
476 try_fit_stack_local (frame_offset
, size
, size
, alignment
, &slot_offset
);
478 if (kind
& ASLK_RECORD_PAD
)
480 if (known_gt (slot_offset
, frame_offset
))
481 add_frame_space (frame_offset
, slot_offset
);
482 if (known_lt (slot_offset
+ size
, old_frame_offset
))
483 add_frame_space (slot_offset
+ size
, old_frame_offset
);
488 frame_offset
+= size
;
489 try_fit_stack_local (old_frame_offset
, size
, size
, alignment
, &slot_offset
);
491 if (kind
& ASLK_RECORD_PAD
)
493 if (known_gt (slot_offset
, old_frame_offset
))
494 add_frame_space (old_frame_offset
, slot_offset
);
495 if (known_lt (slot_offset
+ size
, frame_offset
))
496 add_frame_space (slot_offset
+ size
, frame_offset
);
501 /* On a big-endian machine, if we are allocating more space than we will use,
502 use the least significant bytes of those that are allocated. */
505 /* The slot size can sometimes be smaller than the mode size;
506 e.g. the rs6000 port allocates slots with a vector mode
507 that have the size of only one element. However, the slot
508 size must always be ordered wrt to the mode size, in the
509 same way as for a subreg. */
510 gcc_checking_assert (ordered_p (GET_MODE_SIZE (mode
), size
));
511 if (BYTES_BIG_ENDIAN
&& maybe_lt (GET_MODE_SIZE (mode
), size
))
512 bigend_correction
= size
- GET_MODE_SIZE (mode
);
515 /* If we have already instantiated virtual registers, return the actual
516 address relative to the frame pointer. */
517 if (virtuals_instantiated
)
518 addr
= plus_constant (Pmode
, frame_pointer_rtx
,
520 (slot_offset
+ bigend_correction
521 + targetm
.starting_frame_offset (), Pmode
));
523 addr
= plus_constant (Pmode
, virtual_stack_vars_rtx
,
525 (slot_offset
+ bigend_correction
,
528 x
= gen_rtx_MEM (mode
, addr
);
529 set_mem_align (x
, alignment_in_bits
);
530 MEM_NOTRAP_P (x
) = 1;
532 vec_safe_push (stack_slot_list
, x
);
534 if (frame_offset_overflow (frame_offset
, current_function_decl
))
540 /* Wrap up assign_stack_local_1 with last parameter as false. */
543 assign_stack_local (machine_mode mode
, poly_int64 size
, int align
)
545 return assign_stack_local_1 (mode
, size
, align
, ASLK_RECORD_PAD
);
548 /* In order to evaluate some expressions, such as function calls returning
549 structures in memory, we need to temporarily allocate stack locations.
550 We record each allocated temporary in the following structure.
552 Associated with each temporary slot is a nesting level. When we pop up
553 one level, all temporaries associated with the previous level are freed.
554 Normally, all temporaries are freed after the execution of the statement
555 in which they were created. However, if we are inside a ({...}) grouping,
556 the result may be in a temporary and hence must be preserved. If the
557 result could be in a temporary, we preserve it if we can determine which
558 one it is in. If we cannot determine which temporary may contain the
559 result, all temporaries are preserved. A temporary is preserved by
560 pretending it was allocated at the previous nesting level. */
562 class GTY(()) temp_slot
{
564 /* Points to next temporary slot. */
565 class temp_slot
*next
;
566 /* Points to previous temporary slot. */
567 class temp_slot
*prev
;
568 /* The rtx to used to reference the slot. */
570 /* The size, in units, of the slot. */
572 /* The type of the object in the slot, or zero if it doesn't correspond
573 to a type. We use this to determine whether a slot can be reused.
574 It can be reused if objects of the type of the new slot will always
575 conflict with objects of the type of the old slot. */
577 /* The alignment (in bits) of the slot. */
579 /* Nonzero if this temporary is currently in use. */
581 /* Nesting level at which this slot is being used. */
583 /* The offset of the slot from the frame_pointer, including extra space
584 for alignment. This info is for combine_temp_slots. */
585 poly_int64 base_offset
;
586 /* The size of the slot, including extra space for alignment. This
587 info is for combine_temp_slots. */
588 poly_int64 full_size
;
591 /* Entry for the below hash table. */
592 struct GTY((for_user
)) temp_slot_address_entry
{
595 class temp_slot
*temp_slot
;
598 struct temp_address_hasher
: ggc_ptr_hash
<temp_slot_address_entry
>
600 static hashval_t
hash (temp_slot_address_entry
*);
601 static bool equal (temp_slot_address_entry
*, temp_slot_address_entry
*);
604 /* A table of addresses that represent a stack slot. The table is a mapping
605 from address RTXen to a temp slot. */
606 static GTY(()) hash_table
<temp_address_hasher
> *temp_slot_address_table
;
607 static size_t n_temp_slots_in_use
;
609 /* Removes temporary slot TEMP from LIST. */
612 cut_slot_from_list (class temp_slot
*temp
, class temp_slot
**list
)
615 temp
->next
->prev
= temp
->prev
;
617 temp
->prev
->next
= temp
->next
;
621 temp
->prev
= temp
->next
= NULL
;
624 /* Inserts temporary slot TEMP to LIST. */
627 insert_slot_to_list (class temp_slot
*temp
, class temp_slot
**list
)
631 (*list
)->prev
= temp
;
636 /* Returns the list of used temp slots at LEVEL. */
638 static class temp_slot
**
639 temp_slots_at_level (int level
)
641 if (level
>= (int) vec_safe_length (used_temp_slots
))
642 vec_safe_grow_cleared (used_temp_slots
, level
+ 1, true);
644 return &(*used_temp_slots
)[level
];
647 /* Returns the maximal temporary slot level. */
650 max_slot_level (void)
652 if (!used_temp_slots
)
655 return used_temp_slots
->length () - 1;
658 /* Moves temporary slot TEMP to LEVEL. */
661 move_slot_to_level (class temp_slot
*temp
, int level
)
663 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
664 insert_slot_to_list (temp
, temp_slots_at_level (level
));
668 /* Make temporary slot TEMP available. */
671 make_slot_available (class temp_slot
*temp
)
673 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
674 insert_slot_to_list (temp
, &avail_temp_slots
);
677 n_temp_slots_in_use
--;
680 /* Compute the hash value for an address -> temp slot mapping.
681 The value is cached on the mapping entry. */
683 temp_slot_address_compute_hash (struct temp_slot_address_entry
*t
)
685 int do_not_record
= 0;
686 return hash_rtx (t
->address
, GET_MODE (t
->address
),
687 &do_not_record
, NULL
, false);
690 /* Return the hash value for an address -> temp slot mapping. */
692 temp_address_hasher::hash (temp_slot_address_entry
*t
)
697 /* Compare two address -> temp slot mapping entries. */
699 temp_address_hasher::equal (temp_slot_address_entry
*t1
,
700 temp_slot_address_entry
*t2
)
702 return exp_equiv_p (t1
->address
, t2
->address
, 0, true);
705 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
707 insert_temp_slot_address (rtx address
, class temp_slot
*temp_slot
)
709 struct temp_slot_address_entry
*t
= ggc_alloc
<temp_slot_address_entry
> ();
710 t
->address
= copy_rtx (address
);
711 t
->temp_slot
= temp_slot
;
712 t
->hash
= temp_slot_address_compute_hash (t
);
713 *temp_slot_address_table
->find_slot_with_hash (t
, t
->hash
, INSERT
) = t
;
716 /* Remove an address -> temp slot mapping entry if the temp slot is
717 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
719 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry
**slot
, void *)
721 const struct temp_slot_address_entry
*t
= *slot
;
722 if (! t
->temp_slot
->in_use
)
723 temp_slot_address_table
->clear_slot (slot
);
727 /* Remove all mappings of addresses to unused temp slots. */
729 remove_unused_temp_slot_addresses (void)
731 /* Use quicker clearing if there aren't any active temp slots. */
732 if (n_temp_slots_in_use
)
733 temp_slot_address_table
->traverse
734 <void *, remove_unused_temp_slot_addresses_1
> (NULL
);
736 temp_slot_address_table
->empty ();
739 /* Find the temp slot corresponding to the object at address X. */
741 static class temp_slot
*
742 find_temp_slot_from_address (rtx x
)
745 struct temp_slot_address_entry tmp
, *t
;
747 /* First try the easy way:
748 See if X exists in the address -> temp slot mapping. */
750 tmp
.temp_slot
= NULL
;
751 tmp
.hash
= temp_slot_address_compute_hash (&tmp
);
752 t
= temp_slot_address_table
->find_with_hash (&tmp
, tmp
.hash
);
756 /* If we have a sum involving a register, see if it points to a temp
758 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
759 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
761 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
762 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
765 /* Last resort: Address is a virtual stack var address. */
767 if (strip_offset (x
, &offset
) == virtual_stack_vars_rtx
)
770 for (i
= max_slot_level (); i
>= 0; i
--)
771 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
772 if (known_in_range_p (offset
, p
->base_offset
, p
->full_size
))
779 /* Allocate a temporary stack slot and record it for possible later
782 MODE is the machine mode to be given to the returned rtx.
784 SIZE is the size in units of the space required. We do no rounding here
785 since assign_stack_local will do any required rounding.
787 TYPE is the type that will be used for the stack slot. */
790 assign_stack_temp_for_type (machine_mode mode
, poly_int64 size
, tree type
)
793 class temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
796 gcc_assert (known_size_p (size
));
798 align
= get_stack_local_alignment (type
, mode
);
800 /* Try to find an available, already-allocated temporary of the proper
801 mode which meets the size and alignment requirements. Choose the
802 smallest one with the closest alignment.
804 If assign_stack_temp is called outside of the tree->rtl expansion,
805 we cannot reuse the stack slots (that may still refer to
806 VIRTUAL_STACK_VARS_REGNUM). */
807 if (!virtuals_instantiated
)
809 for (p
= avail_temp_slots
; p
; p
= p
->next
)
811 if (p
->align
>= align
812 && known_ge (p
->size
, size
)
813 && GET_MODE (p
->slot
) == mode
814 && objects_must_conflict_p (p
->type
, type
)
816 || (known_eq (best_p
->size
, p
->size
)
817 ? best_p
->align
> p
->align
818 : known_ge (best_p
->size
, p
->size
))))
820 if (p
->align
== align
&& known_eq (p
->size
, size
))
823 cut_slot_from_list (selected
, &avail_temp_slots
);
832 /* Make our best, if any, the one to use. */
836 cut_slot_from_list (selected
, &avail_temp_slots
);
838 /* If there are enough aligned bytes left over, make them into a new
839 temp_slot so that the extra bytes don't get wasted. Do this only
840 for BLKmode slots, so that we can be sure of the alignment. */
841 if (GET_MODE (best_p
->slot
) == BLKmode
)
843 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
844 poly_int64 rounded_size
= aligned_upper_bound (size
, alignment
);
846 if (known_ge (best_p
->size
- rounded_size
, alignment
))
848 p
= ggc_alloc
<temp_slot
> ();
850 p
->size
= best_p
->size
- rounded_size
;
851 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
852 p
->full_size
= best_p
->full_size
- rounded_size
;
853 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
854 p
->align
= best_p
->align
;
855 p
->type
= best_p
->type
;
856 insert_slot_to_list (p
, &avail_temp_slots
);
858 vec_safe_push (stack_slot_list
, p
->slot
);
860 best_p
->size
= rounded_size
;
861 best_p
->full_size
= rounded_size
;
866 /* If we still didn't find one, make a new temporary. */
869 poly_int64 frame_offset_old
= frame_offset
;
871 p
= ggc_alloc
<temp_slot
> ();
873 /* We are passing an explicit alignment request to assign_stack_local.
874 One side effect of that is assign_stack_local will not round SIZE
875 to ensure the frame offset remains suitably aligned.
877 So for requests which depended on the rounding of SIZE, we go ahead
878 and round it now. We also make sure ALIGNMENT is at least
879 BIGGEST_ALIGNMENT. */
880 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
881 p
->slot
= assign_stack_local_1 (mode
,
883 ? aligned_upper_bound (size
,
891 /* The following slot size computation is necessary because we don't
892 know the actual size of the temporary slot until assign_stack_local
893 has performed all the frame alignment and size rounding for the
894 requested temporary. Note that extra space added for alignment
895 can be either above or below this stack slot depending on which
896 way the frame grows. We include the extra space if and only if it
897 is above this slot. */
898 if (FRAME_GROWS_DOWNWARD
)
899 p
->size
= frame_offset_old
- frame_offset
;
903 /* Now define the fields used by combine_temp_slots. */
904 if (FRAME_GROWS_DOWNWARD
)
906 p
->base_offset
= frame_offset
;
907 p
->full_size
= frame_offset_old
- frame_offset
;
911 p
->base_offset
= frame_offset_old
;
912 p
->full_size
= frame_offset
- frame_offset_old
;
921 p
->level
= temp_slot_level
;
922 n_temp_slots_in_use
++;
924 pp
= temp_slots_at_level (p
->level
);
925 insert_slot_to_list (p
, pp
);
926 insert_temp_slot_address (XEXP (p
->slot
, 0), p
);
928 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
929 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
930 vec_safe_push (stack_slot_list
, slot
);
932 /* If we know the alias set for the memory that will be used, use
933 it. If there's no TYPE, then we don't know anything about the
934 alias set for the memory. */
935 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
936 set_mem_align (slot
, align
);
938 /* If a type is specified, set the relevant flags. */
940 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
941 MEM_NOTRAP_P (slot
) = 1;
946 /* Allocate a temporary stack slot and record it for possible later
947 reuse. First two arguments are same as in preceding function. */
950 assign_stack_temp (machine_mode mode
, poly_int64 size
)
952 return assign_stack_temp_for_type (mode
, size
, NULL_TREE
);
955 /* Assign a temporary.
956 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
957 and so that should be used in error messages. In either case, we
958 allocate of the given type.
959 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
960 it is 0 if a register is OK.
961 DONT_PROMOTE is 1 if we should not promote values in register
965 assign_temp (tree type_or_decl
, int memory_required
,
966 int dont_promote ATTRIBUTE_UNUSED
)
974 if (DECL_P (type_or_decl
))
975 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
977 decl
= NULL
, type
= type_or_decl
;
979 mode
= TYPE_MODE (type
);
981 unsignedp
= TYPE_UNSIGNED (type
);
984 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
985 end. See also create_tmp_var for the gimplification-time check. */
986 gcc_assert (!TREE_ADDRESSABLE (type
) && COMPLETE_TYPE_P (type
));
988 if (mode
== BLKmode
|| memory_required
)
993 /* Unfortunately, we don't yet know how to allocate variable-sized
994 temporaries. However, sometimes we can find a fixed upper limit on
995 the size, so try that instead. */
996 if (!poly_int_tree_p (TYPE_SIZE_UNIT (type
), &size
))
997 size
= max_int_size_in_bytes (type
);
999 /* Zero sized arrays are a GNU C extension. Set size to 1 to avoid
1000 problems with allocating the stack space. */
1001 if (known_eq (size
, 0))
1004 /* The size of the temporary may be too large to fit into an integer. */
1005 /* ??? Not sure this should happen except for user silliness, so limit
1006 this to things that aren't compiler-generated temporaries. The
1007 rest of the time we'll die in assign_stack_temp_for_type. */
1009 && !known_size_p (size
)
1010 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
1012 error ("size of variable %q+D is too large", decl
);
1016 tmp
= assign_stack_temp_for_type (mode
, size
, type
);
1022 mode
= promote_mode (type
, mode
, &unsignedp
);
1025 return gen_reg_rtx (mode
);
1028 /* Combine temporary stack slots which are adjacent on the stack.
1030 This allows for better use of already allocated stack space. This is only
1031 done for BLKmode slots because we can be sure that we won't have alignment
1032 problems in this case. */
1035 combine_temp_slots (void)
1037 class temp_slot
*p
, *q
, *next
, *next_q
;
1040 /* We can't combine slots, because the information about which slot
1041 is in which alias set will be lost. */
1042 if (flag_strict_aliasing
)
1045 /* If there are a lot of temp slots, don't do anything unless
1046 high levels of optimization. */
1047 if (! flag_expensive_optimizations
)
1048 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
1049 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
1052 for (p
= avail_temp_slots
; p
; p
= next
)
1058 if (GET_MODE (p
->slot
) != BLKmode
)
1061 for (q
= p
->next
; q
; q
= next_q
)
1067 if (GET_MODE (q
->slot
) != BLKmode
)
1070 if (known_eq (p
->base_offset
+ p
->full_size
, q
->base_offset
))
1072 /* Q comes after P; combine Q into P. */
1074 p
->full_size
+= q
->full_size
;
1077 else if (known_eq (q
->base_offset
+ q
->full_size
, p
->base_offset
))
1079 /* P comes after Q; combine P into Q. */
1081 q
->full_size
+= p
->full_size
;
1086 cut_slot_from_list (q
, &avail_temp_slots
);
1089 /* Either delete P or advance past it. */
1091 cut_slot_from_list (p
, &avail_temp_slots
);
1095 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1096 slot that previously was known by OLD_RTX. */
1099 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
1103 if (rtx_equal_p (old_rtx
, new_rtx
))
1106 p
= find_temp_slot_from_address (old_rtx
);
1108 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1109 NEW_RTX is a register, see if one operand of the PLUS is a
1110 temporary location. If so, NEW_RTX points into it. Otherwise,
1111 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1112 in common between them. If so, try a recursive call on those
1116 if (GET_CODE (old_rtx
) != PLUS
)
1119 if (REG_P (new_rtx
))
1121 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
1122 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
1125 else if (GET_CODE (new_rtx
) != PLUS
)
1128 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
1129 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
1130 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
1131 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
1132 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
1133 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
1134 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
1135 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
1140 /* Otherwise add an alias for the temp's address. */
1141 insert_temp_slot_address (new_rtx
, p
);
1144 /* If X could be a reference to a temporary slot, mark that slot as
1145 belonging to the to one level higher than the current level. If X
1146 matched one of our slots, just mark that one. Otherwise, we can't
1147 easily predict which it is, so upgrade all of them.
1149 This is called when an ({...}) construct occurs and a statement
1150 returns a value in memory. */
1153 preserve_temp_slots (rtx x
)
1155 class temp_slot
*p
= 0, *next
;
1160 /* If X is a register that is being used as a pointer, see if we have
1161 a temporary slot we know it points to. */
1162 if (REG_P (x
) && REG_POINTER (x
))
1163 p
= find_temp_slot_from_address (x
);
1165 /* If X is not in memory or is at a constant address, it cannot be in
1166 a temporary slot. */
1167 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1170 /* First see if we can find a match. */
1172 p
= find_temp_slot_from_address (XEXP (x
, 0));
1176 if (p
->level
== temp_slot_level
)
1177 move_slot_to_level (p
, temp_slot_level
- 1);
1181 /* Otherwise, preserve all non-kept slots at this level. */
1182 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1185 move_slot_to_level (p
, temp_slot_level
- 1);
1189 /* Free all temporaries used so far. This is normally called at the
1190 end of generating code for a statement. */
1193 free_temp_slots (void)
1195 class temp_slot
*p
, *next
;
1196 bool some_available
= false;
1198 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1201 make_slot_available (p
);
1202 some_available
= true;
1207 remove_unused_temp_slot_addresses ();
1208 combine_temp_slots ();
1212 /* Push deeper into the nesting level for stack temporaries. */
1215 push_temp_slots (void)
1220 /* Pop a temporary nesting level. All slots in use in the current level
1224 pop_temp_slots (void)
1230 /* Initialize temporary slots. */
1233 init_temp_slots (void)
1235 /* We have not allocated any temporaries yet. */
1236 avail_temp_slots
= 0;
1237 vec_alloc (used_temp_slots
, 0);
1238 temp_slot_level
= 0;
1239 n_temp_slots_in_use
= 0;
1241 /* Set up the table to map addresses to temp slots. */
1242 if (! temp_slot_address_table
)
1243 temp_slot_address_table
= hash_table
<temp_address_hasher
>::create_ggc (32);
1245 temp_slot_address_table
->empty ();
1248 /* Functions and data structures to keep track of the values hard regs
1249 had at the start of the function. */
1251 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1252 and has_hard_reg_initial_val.. */
1253 struct GTY(()) initial_value_pair
{
1257 /* ??? This could be a VEC but there is currently no way to define an
1258 opaque VEC type. This could be worked around by defining struct
1259 initial_value_pair in function.h. */
1260 struct GTY(()) initial_value_struct
{
1263 initial_value_pair
* GTY ((length ("%h.num_entries"))) entries
;
1266 /* If a pseudo represents an initial hard reg (or expression), return
1267 it, else return NULL_RTX. */
1270 get_hard_reg_initial_reg (rtx reg
)
1272 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1278 for (i
= 0; i
< ivs
->num_entries
; i
++)
1279 if (rtx_equal_p (ivs
->entries
[i
].pseudo
, reg
))
1280 return ivs
->entries
[i
].hard_reg
;
1285 /* Make sure that there's a pseudo register of mode MODE that stores the
1286 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1289 get_hard_reg_initial_val (machine_mode mode
, unsigned int regno
)
1291 struct initial_value_struct
*ivs
;
1294 rv
= has_hard_reg_initial_val (mode
, regno
);
1298 ivs
= crtl
->hard_reg_initial_vals
;
1301 ivs
= ggc_alloc
<initial_value_struct
> ();
1302 ivs
->num_entries
= 0;
1303 ivs
->max_entries
= 5;
1304 ivs
->entries
= ggc_vec_alloc
<initial_value_pair
> (5);
1305 crtl
->hard_reg_initial_vals
= ivs
;
1308 if (ivs
->num_entries
>= ivs
->max_entries
)
1310 ivs
->max_entries
+= 5;
1311 ivs
->entries
= GGC_RESIZEVEC (initial_value_pair
, ivs
->entries
,
1315 ivs
->entries
[ivs
->num_entries
].hard_reg
= gen_rtx_REG (mode
, regno
);
1316 ivs
->entries
[ivs
->num_entries
].pseudo
= gen_reg_rtx (mode
);
1318 return ivs
->entries
[ivs
->num_entries
++].pseudo
;
1321 /* See if get_hard_reg_initial_val has been used to create a pseudo
1322 for the initial value of hard register REGNO in mode MODE. Return
1323 the associated pseudo if so, otherwise return NULL. */
1326 has_hard_reg_initial_val (machine_mode mode
, unsigned int regno
)
1328 struct initial_value_struct
*ivs
;
1331 ivs
= crtl
->hard_reg_initial_vals
;
1333 for (i
= 0; i
< ivs
->num_entries
; i
++)
1334 if (GET_MODE (ivs
->entries
[i
].hard_reg
) == mode
1335 && REGNO (ivs
->entries
[i
].hard_reg
) == regno
)
1336 return ivs
->entries
[i
].pseudo
;
1342 emit_initial_value_sets (void)
1344 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1352 for (i
= 0; i
< ivs
->num_entries
; i
++)
1353 emit_move_insn (ivs
->entries
[i
].pseudo
, ivs
->entries
[i
].hard_reg
);
1357 emit_insn_at_entry (seq
);
1361 /* Return the hardreg-pseudoreg initial values pair entry I and
1362 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1364 initial_value_entry (int i
, rtx
*hreg
, rtx
*preg
)
1366 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1367 if (!ivs
|| i
>= ivs
->num_entries
)
1370 *hreg
= ivs
->entries
[i
].hard_reg
;
1371 *preg
= ivs
->entries
[i
].pseudo
;
1375 /* These routines are responsible for converting virtual register references
1376 to the actual hard register references once RTL generation is complete.
1378 The following four variables are used for communication between the
1379 routines. They contain the offsets of the virtual registers from their
1380 respective hard registers. */
1382 static poly_int64 in_arg_offset
;
1383 static poly_int64 var_offset
;
1384 static poly_int64 dynamic_offset
;
1385 static poly_int64 out_arg_offset
;
1386 static poly_int64 cfa_offset
;
1388 /* In most machines, the stack pointer register is equivalent to the bottom
1391 #ifndef STACK_POINTER_OFFSET
1392 #define STACK_POINTER_OFFSET 0
1395 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1396 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1399 /* If not defined, pick an appropriate default for the offset of dynamically
1400 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1401 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1403 #ifndef STACK_DYNAMIC_OFFSET
1405 /* The bottom of the stack points to the actual arguments. If
1406 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1407 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1408 stack space for register parameters is not pushed by the caller, but
1409 rather part of the fixed stack areas and hence not included in
1410 `crtl->outgoing_args_size'. Nevertheless, we must allow
1411 for it when allocating stack dynamic objects. */
1413 #ifdef INCOMING_REG_PARM_STACK_SPACE
1414 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1415 ((ACCUMULATE_OUTGOING_ARGS \
1416 ? (crtl->outgoing_args_size \
1417 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1418 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1419 : 0) + (STACK_POINTER_OFFSET))
1421 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1422 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : poly_int64 (0)) \
1423 + (STACK_POINTER_OFFSET))
1428 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1429 is a virtual register, return the equivalent hard register and set the
1430 offset indirectly through the pointer. Otherwise, return 0. */
1433 instantiate_new_reg (rtx x
, poly_int64_pod
*poffset
)
1438 if (x
== virtual_incoming_args_rtx
)
1440 if (stack_realign_drap
)
1442 /* Replace virtual_incoming_args_rtx with internal arg
1443 pointer if DRAP is used to realign stack. */
1444 new_rtx
= crtl
->args
.internal_arg_pointer
;
1448 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1450 else if (x
== virtual_stack_vars_rtx
)
1451 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1452 else if (x
== virtual_stack_dynamic_rtx
)
1453 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1454 else if (x
== virtual_outgoing_args_rtx
)
1455 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1456 else if (x
== virtual_cfa_rtx
)
1458 #ifdef FRAME_POINTER_CFA_OFFSET
1459 new_rtx
= frame_pointer_rtx
;
1461 new_rtx
= arg_pointer_rtx
;
1463 offset
= cfa_offset
;
1465 else if (x
== virtual_preferred_stack_boundary_rtx
)
1467 new_rtx
= GEN_INT (crtl
->preferred_stack_boundary
/ BITS_PER_UNIT
);
1477 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1478 registers present inside of *LOC. The expression is simplified,
1479 as much as possible, but is not to be considered "valid" in any sense
1480 implied by the target. Return true if any change is made. */
1483 instantiate_virtual_regs_in_rtx (rtx
*loc
)
1487 bool changed
= false;
1488 subrtx_ptr_iterator::array_type array
;
1489 FOR_EACH_SUBRTX_PTR (iter
, array
, loc
, NONCONST
)
1496 switch (GET_CODE (x
))
1499 new_rtx
= instantiate_new_reg (x
, &offset
);
1502 *loc
= plus_constant (GET_MODE (x
), new_rtx
, offset
);
1505 iter
.skip_subrtxes ();
1509 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1512 XEXP (x
, 0) = new_rtx
;
1513 *loc
= plus_constant (GET_MODE (x
), x
, offset
, true);
1515 iter
.skip_subrtxes ();
1519 /* FIXME -- from old code */
1520 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1521 we can commute the PLUS and SUBREG because pointers into the
1522 frame are well-behaved. */
1533 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1534 matches the predicate for insn CODE operand OPERAND. */
1537 safe_insn_predicate (int code
, int operand
, rtx x
)
1539 return code
< 0 || insn_operand_matches ((enum insn_code
) code
, operand
, x
);
1542 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1543 registers present inside of insn. The result will be a valid insn. */
1546 instantiate_virtual_regs_in_insn (rtx_insn
*insn
)
1550 bool any_change
= false;
1551 rtx set
, new_rtx
, x
;
1554 /* There are some special cases to be handled first. */
1555 set
= single_set (insn
);
1558 /* We're allowed to assign to a virtual register. This is interpreted
1559 to mean that the underlying register gets assigned the inverse
1560 transformation. This is used, for example, in the handling of
1562 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1567 instantiate_virtual_regs_in_rtx (&SET_SRC (set
));
1568 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1569 gen_int_mode (-offset
, GET_MODE (new_rtx
)));
1570 x
= force_operand (x
, new_rtx
);
1572 emit_move_insn (new_rtx
, x
);
1577 emit_insn_before (seq
, insn
);
1582 /* Handle a straight copy from a virtual register by generating a
1583 new add insn. The difference between this and falling through
1584 to the generic case is avoiding a new pseudo and eliminating a
1585 move insn in the initial rtl stream. */
1586 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1588 && maybe_ne (offset
, 0)
1589 && REG_P (SET_DEST (set
))
1590 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1594 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
, new_rtx
,
1595 gen_int_mode (offset
,
1596 GET_MODE (SET_DEST (set
))),
1597 SET_DEST (set
), 1, OPTAB_LIB_WIDEN
);
1598 if (x
!= SET_DEST (set
))
1599 emit_move_insn (SET_DEST (set
), x
);
1604 emit_insn_before (seq
, insn
);
1609 extract_insn (insn
);
1610 insn_code
= INSN_CODE (insn
);
1612 /* Handle a plus involving a virtual register by determining if the
1613 operands remain valid if they're modified in place. */
1615 if (GET_CODE (SET_SRC (set
)) == PLUS
1616 && recog_data
.n_operands
>= 3
1617 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1618 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1619 && poly_int_rtx_p (recog_data
.operand
[2], &delta
)
1620 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1624 /* If the sum is zero, then replace with a plain move. */
1625 if (known_eq (offset
, 0)
1626 && REG_P (SET_DEST (set
))
1627 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1630 emit_move_insn (SET_DEST (set
), new_rtx
);
1634 emit_insn_before (seq
, insn
);
1639 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1641 /* Using validate_change and apply_change_group here leaves
1642 recog_data in an invalid state. Since we know exactly what
1643 we want to check, do those two by hand. */
1644 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1645 && safe_insn_predicate (insn_code
, 2, x
))
1647 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1648 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1651 /* Fall through into the regular operand fixup loop in
1652 order to take care of operands other than 1 and 2. */
1658 extract_insn (insn
);
1659 insn_code
= INSN_CODE (insn
);
1662 /* In the general case, we expect virtual registers to appear only in
1663 operands, and then only as either bare registers or inside memories. */
1664 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1666 x
= recog_data
.operand
[i
];
1667 switch (GET_CODE (x
))
1671 rtx addr
= XEXP (x
, 0);
1673 if (!instantiate_virtual_regs_in_rtx (&addr
))
1677 x
= replace_equiv_address (x
, addr
, true);
1678 /* It may happen that the address with the virtual reg
1679 was valid (e.g. based on the virtual stack reg, which might
1680 be acceptable to the predicates with all offsets), whereas
1681 the address now isn't anymore, for instance when the address
1682 is still offsetted, but the base reg isn't virtual-stack-reg
1683 anymore. Below we would do a force_reg on the whole operand,
1684 but this insn might actually only accept memory. Hence,
1685 before doing that last resort, try to reload the address into
1686 a register, so this operand stays a MEM. */
1687 if (!safe_insn_predicate (insn_code
, i
, x
))
1689 addr
= force_reg (GET_MODE (addr
), addr
);
1690 x
= replace_equiv_address (x
, addr
, true);
1695 emit_insn_before (seq
, insn
);
1700 new_rtx
= instantiate_new_reg (x
, &offset
);
1701 if (new_rtx
== NULL
)
1703 if (known_eq (offset
, 0))
1709 /* Careful, special mode predicates may have stuff in
1710 insn_data[insn_code].operand[i].mode that isn't useful
1711 to us for computing a new value. */
1712 /* ??? Recognize address_operand and/or "p" constraints
1713 to see if (plus new offset) is a valid before we put
1714 this through expand_simple_binop. */
1715 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1716 gen_int_mode (offset
, GET_MODE (x
)),
1717 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1720 emit_insn_before (seq
, insn
);
1725 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1726 if (new_rtx
== NULL
)
1728 if (maybe_ne (offset
, 0))
1731 new_rtx
= expand_simple_binop
1732 (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1733 gen_int_mode (offset
, GET_MODE (new_rtx
)),
1734 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1737 emit_insn_before (seq
, insn
);
1739 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1740 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1748 /* At this point, X contains the new value for the operand.
1749 Validate the new value vs the insn predicate. Note that
1750 asm insns will have insn_code -1 here. */
1751 if (!safe_insn_predicate (insn_code
, i
, x
))
1756 gcc_assert (REGNO (x
) <= LAST_VIRTUAL_REGISTER
);
1757 x
= copy_to_reg (x
);
1760 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1764 emit_insn_before (seq
, insn
);
1767 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1773 /* Propagate operand changes into the duplicates. */
1774 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1775 *recog_data
.dup_loc
[i
]
1776 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1778 /* Force re-recognition of the instruction for validation. */
1779 INSN_CODE (insn
) = -1;
1782 if (asm_noperands (PATTERN (insn
)) >= 0)
1784 if (!check_asm_operands (PATTERN (insn
)))
1786 error_for_asm (insn
, "impossible constraint in %<asm%>");
1787 /* For asm goto, instead of fixing up all the edges
1788 just clear the template and clear input operands
1789 (asm goto doesn't have any output operands). */
1792 rtx asm_op
= extract_asm_operands (PATTERN (insn
));
1793 ASM_OPERANDS_TEMPLATE (asm_op
) = ggc_strdup ("");
1794 ASM_OPERANDS_INPUT_VEC (asm_op
) = rtvec_alloc (0);
1795 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op
) = rtvec_alloc (0);
1803 if (recog_memoized (insn
) < 0)
1804 fatal_insn_not_found (insn
);
1808 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1809 do any instantiation required. */
1812 instantiate_decl_rtl (rtx x
)
1819 /* If this is a CONCAT, recurse for the pieces. */
1820 if (GET_CODE (x
) == CONCAT
)
1822 instantiate_decl_rtl (XEXP (x
, 0));
1823 instantiate_decl_rtl (XEXP (x
, 1));
1827 /* If this is not a MEM, no need to do anything. Similarly if the
1828 address is a constant or a register that is not a virtual register. */
1833 if (CONSTANT_P (addr
)
1835 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1836 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1839 instantiate_virtual_regs_in_rtx (&XEXP (x
, 0));
1842 /* Helper for instantiate_decls called via walk_tree: Process all decls
1843 in the given DECL_VALUE_EXPR. */
1846 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1854 if (DECL_RTL_SET_P (t
))
1855 instantiate_decl_rtl (DECL_RTL (t
));
1856 if (TREE_CODE (t
) == PARM_DECL
&& DECL_NAMELESS (t
)
1857 && DECL_INCOMING_RTL (t
))
1858 instantiate_decl_rtl (DECL_INCOMING_RTL (t
));
1859 if ((VAR_P (t
) || TREE_CODE (t
) == RESULT_DECL
)
1860 && DECL_HAS_VALUE_EXPR_P (t
))
1862 tree v
= DECL_VALUE_EXPR (t
);
1863 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1870 /* Subroutine of instantiate_decls: Process all decls in the given
1871 BLOCK node and all its subblocks. */
1874 instantiate_decls_1 (tree let
)
1878 for (t
= BLOCK_VARS (let
); t
; t
= DECL_CHAIN (t
))
1880 if (DECL_RTL_SET_P (t
))
1881 instantiate_decl_rtl (DECL_RTL (t
));
1882 if (VAR_P (t
) && DECL_HAS_VALUE_EXPR_P (t
))
1884 tree v
= DECL_VALUE_EXPR (t
);
1885 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1889 /* Process all subblocks. */
1890 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1891 instantiate_decls_1 (t
);
1894 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1895 all virtual registers in their DECL_RTL's. */
1898 instantiate_decls (tree fndecl
)
1903 /* Process all parameters of the function. */
1904 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= DECL_CHAIN (decl
))
1906 instantiate_decl_rtl (DECL_RTL (decl
));
1907 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1908 if (DECL_HAS_VALUE_EXPR_P (decl
))
1910 tree v
= DECL_VALUE_EXPR (decl
);
1911 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1915 if ((decl
= DECL_RESULT (fndecl
))
1916 && TREE_CODE (decl
) == RESULT_DECL
)
1918 if (DECL_RTL_SET_P (decl
))
1919 instantiate_decl_rtl (DECL_RTL (decl
));
1920 if (DECL_HAS_VALUE_EXPR_P (decl
))
1922 tree v
= DECL_VALUE_EXPR (decl
);
1923 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1927 /* Process the saved static chain if it exists. */
1928 decl
= DECL_STRUCT_FUNCTION (fndecl
)->static_chain_decl
;
1929 if (decl
&& DECL_HAS_VALUE_EXPR_P (decl
))
1930 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl
)));
1932 /* Now process all variables defined in the function or its subblocks. */
1933 if (DECL_INITIAL (fndecl
))
1934 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1936 FOR_EACH_LOCAL_DECL (cfun
, ix
, decl
)
1937 if (DECL_RTL_SET_P (decl
))
1938 instantiate_decl_rtl (DECL_RTL (decl
));
1939 vec_free (cfun
->local_decls
);
1942 /* Pass through the INSNS of function FNDECL and convert virtual register
1943 references to hard register references. */
1946 instantiate_virtual_regs (void)
1950 /* Compute the offsets to use for this function. */
1951 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1952 var_offset
= targetm
.starting_frame_offset ();
1953 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1954 out_arg_offset
= STACK_POINTER_OFFSET
;
1955 #ifdef FRAME_POINTER_CFA_OFFSET
1956 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1958 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1961 /* Initialize recognition, indicating that volatile is OK. */
1964 /* Scan through all the insns, instantiating every virtual register still
1966 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1969 /* These patterns in the instruction stream can never be recognized.
1970 Fortunately, they shouldn't contain virtual registers either. */
1971 if (GET_CODE (PATTERN (insn
)) == USE
1972 || GET_CODE (PATTERN (insn
)) == CLOBBER
1973 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
1974 || DEBUG_MARKER_INSN_P (insn
))
1976 else if (DEBUG_BIND_INSN_P (insn
))
1977 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn
));
1979 instantiate_virtual_regs_in_insn (insn
);
1981 if (insn
->deleted ())
1984 instantiate_virtual_regs_in_rtx (®_NOTES (insn
));
1986 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1988 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn
));
1991 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1992 instantiate_decls (current_function_decl
);
1994 targetm
.instantiate_decls ();
1996 /* Indicate that, from now on, assign_stack_local should use
1997 frame_pointer_rtx. */
1998 virtuals_instantiated
= 1;
2005 const pass_data pass_data_instantiate_virtual_regs
=
2007 RTL_PASS
, /* type */
2009 OPTGROUP_NONE
, /* optinfo_flags */
2010 TV_NONE
, /* tv_id */
2011 0, /* properties_required */
2012 0, /* properties_provided */
2013 0, /* properties_destroyed */
2014 0, /* todo_flags_start */
2015 0, /* todo_flags_finish */
2018 class pass_instantiate_virtual_regs
: public rtl_opt_pass
2021 pass_instantiate_virtual_regs (gcc::context
*ctxt
)
2022 : rtl_opt_pass (pass_data_instantiate_virtual_regs
, ctxt
)
2025 /* opt_pass methods: */
2026 virtual unsigned int execute (function
*)
2028 return instantiate_virtual_regs ();
2031 }; // class pass_instantiate_virtual_regs
2036 make_pass_instantiate_virtual_regs (gcc::context
*ctxt
)
2038 return new pass_instantiate_virtual_regs (ctxt
);
2042 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2043 This means a type for which function calls must pass an address to the
2044 function or get an address back from the function.
2045 EXP may be a type node or an expression (whose type is tested). */
2048 aggregate_value_p (const_tree exp
, const_tree fntype
)
2050 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
2051 int i
, regno
, nregs
;
2055 switch (TREE_CODE (fntype
))
2059 tree fndecl
= get_callee_fndecl (fntype
);
2061 fntype
= TREE_TYPE (fndecl
);
2062 else if (CALL_EXPR_FN (fntype
))
2063 fntype
= TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype
)));
2065 /* For internal functions, assume nothing needs to be
2066 returned in memory. */
2071 fntype
= TREE_TYPE (fntype
);
2076 case IDENTIFIER_NODE
:
2080 /* We don't expect other tree types here. */
2084 if (VOID_TYPE_P (type
))
2087 /* If a record should be passed the same as its first (and only) member
2088 don't pass it as an aggregate. */
2089 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2090 return aggregate_value_p (first_field (type
), fntype
);
2092 /* If the front end has decided that this needs to be passed by
2093 reference, do so. */
2094 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
2095 && DECL_BY_REFERENCE (exp
))
2098 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2099 if (fntype
&& TREE_ADDRESSABLE (fntype
))
2102 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2103 and thus can't be returned in registers. */
2104 if (TREE_ADDRESSABLE (type
))
2107 if (TYPE_EMPTY_P (type
))
2110 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
2113 if (targetm
.calls
.return_in_memory (type
, fntype
))
2116 /* Make sure we have suitable call-clobbered regs to return
2117 the value in; if not, we must return it in memory. */
2118 reg
= hard_function_value (type
, 0, fntype
, 0);
2120 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2125 /* Use the default ABI if the type of the function isn't known.
2126 The scheme for handling interoperability between different ABIs
2127 requires us to be able to tell when we're calling a function with
2128 a nondefault ABI. */
2129 const predefined_function_abi
&abi
= (fntype
2130 ? fntype_abi (fntype
)
2131 : default_function_abi
);
2132 regno
= REGNO (reg
);
2133 nregs
= hard_regno_nregs (regno
, TYPE_MODE (type
));
2134 for (i
= 0; i
< nregs
; i
++)
2135 if (!fixed_regs
[regno
+ i
] && !abi
.clobbers_full_reg_p (regno
+ i
))
2141 /* Return true if we should assign DECL a pseudo register; false if it
2142 should live on the local stack. */
2145 use_register_for_decl (const_tree decl
)
2147 if (TREE_CODE (decl
) == SSA_NAME
)
2149 /* We often try to use the SSA_NAME, instead of its underlying
2150 decl, to get type information and guide decisions, to avoid
2151 differences of behavior between anonymous and named
2152 variables, but in this one case we have to go for the actual
2153 variable if there is one. The main reason is that, at least
2154 at -O0, we want to place user variables on the stack, but we
2155 don't mind using pseudos for anonymous or ignored temps.
2156 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2157 should go in pseudos, whereas their corresponding variables
2158 might have to go on the stack. So, disregarding the decl
2159 here would negatively impact debug info at -O0, enable
2160 coalescing between SSA_NAMEs that ought to get different
2161 stack/pseudo assignments, and get the incoming argument
2162 processing thoroughly confused by PARM_DECLs expected to live
2163 in stack slots but assigned to pseudos. */
2164 if (!SSA_NAME_VAR (decl
))
2165 return TYPE_MODE (TREE_TYPE (decl
)) != BLKmode
2166 && !(flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)));
2168 decl
= SSA_NAME_VAR (decl
);
2171 /* Honor volatile. */
2172 if (TREE_SIDE_EFFECTS (decl
))
2175 /* Honor addressability. */
2176 if (TREE_ADDRESSABLE (decl
))
2179 /* RESULT_DECLs are a bit special in that they're assigned without
2180 regard to use_register_for_decl, but we generally only store in
2181 them. If we coalesce their SSA NAMEs, we'd better return a
2182 result that matches the assignment in expand_function_start. */
2183 if (TREE_CODE (decl
) == RESULT_DECL
)
2185 /* If it's not an aggregate, we're going to use a REG or a
2186 PARALLEL containing a REG. */
2187 if (!aggregate_value_p (decl
, current_function_decl
))
2190 /* If expand_function_start determines the return value, we'll
2191 use MEM if it's not by reference. */
2192 if (cfun
->returns_pcc_struct
2193 || (targetm
.calls
.struct_value_rtx
2194 (TREE_TYPE (current_function_decl
), 1)))
2195 return DECL_BY_REFERENCE (decl
);
2197 /* Otherwise, we're taking an extra all.function_result_decl
2198 argument. It's set up in assign_parms_augmented_arg_list,
2199 under the (negated) conditions above, and then it's used to
2200 set up the RESULT_DECL rtl in assign_params, after looping
2201 over all parameters. Now, if the RESULT_DECL is not by
2202 reference, we'll use a MEM either way. */
2203 if (!DECL_BY_REFERENCE (decl
))
2206 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2207 the function_result_decl's assignment. Since it's a pointer,
2208 we can short-circuit a number of the tests below, and we must
2209 duplicate them because we don't have the function_result_decl
2211 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2213 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2216 if (cfun
->tail_call_marked
)
2218 /* We don't set DECL_REGISTER for the function_result_decl. */
2222 /* Only register-like things go in registers. */
2223 if (DECL_MODE (decl
) == BLKmode
)
2226 /* If -ffloat-store specified, don't put explicit float variables
2228 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2229 propagates values across these stores, and it probably shouldn't. */
2230 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
2233 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2236 /* If we're not interested in tracking debugging information for
2237 this decl, then we can certainly put it in a register. */
2238 if (DECL_IGNORED_P (decl
))
2244 /* Thunks force a tail call even at -O0 so we need to avoid creating a
2245 dangling reference in case the parameter is passed by reference. */
2246 if (TREE_CODE (decl
) == PARM_DECL
&& cfun
->tail_call_marked
)
2249 if (!DECL_REGISTER (decl
))
2252 /* When not optimizing, disregard register keyword for types that
2253 could have methods, otherwise the methods won't be callable from
2255 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl
)))
2261 /* Structures to communicate between the subroutines of assign_parms.
2262 The first holds data persistent across all parameters, the second
2263 is cleared out for each parameter. */
2265 struct assign_parm_data_all
2267 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2268 should become a job of the target or otherwise encapsulated. */
2269 CUMULATIVE_ARGS args_so_far_v
;
2270 cumulative_args_t args_so_far
;
2271 struct args_size stack_args_size
;
2272 tree function_result_decl
;
2274 rtx_insn
*first_conversion_insn
;
2275 rtx_insn
*last_conversion_insn
;
2276 HOST_WIDE_INT pretend_args_size
;
2277 HOST_WIDE_INT extra_pretend_bytes
;
2278 int reg_parm_stack_space
;
2281 struct assign_parm_data_one
2284 function_arg_info arg
;
2287 machine_mode nominal_mode
;
2288 machine_mode passed_mode
;
2289 struct locate_and_pad_arg_data locate
;
2293 /* A subroutine of assign_parms. Initialize ALL. */
2296 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2298 tree fntype ATTRIBUTE_UNUSED
;
2300 memset (all
, 0, sizeof (*all
));
2302 fntype
= TREE_TYPE (current_function_decl
);
2304 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2305 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
);
2307 INIT_CUMULATIVE_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
,
2308 current_function_decl
, -1);
2310 all
->args_so_far
= pack_cumulative_args (&all
->args_so_far_v
);
2312 #ifdef INCOMING_REG_PARM_STACK_SPACE
2313 all
->reg_parm_stack_space
2314 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl
);
2318 /* If ARGS contains entries with complex types, split the entry into two
2319 entries of the component type. Return a new list of substitutions are
2320 needed, else the old list. */
2323 split_complex_args (vec
<tree
> *args
)
2328 FOR_EACH_VEC_ELT (*args
, i
, p
)
2330 tree type
= TREE_TYPE (p
);
2331 if (TREE_CODE (type
) == COMPLEX_TYPE
2332 && targetm
.calls
.split_complex_arg (type
))
2335 tree subtype
= TREE_TYPE (type
);
2336 bool addressable
= TREE_ADDRESSABLE (p
);
2338 /* Rewrite the PARM_DECL's type with its component. */
2340 TREE_TYPE (p
) = subtype
;
2341 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2342 SET_DECL_MODE (p
, VOIDmode
);
2343 DECL_SIZE (p
) = NULL
;
2344 DECL_SIZE_UNIT (p
) = NULL
;
2345 /* If this arg must go in memory, put it in a pseudo here.
2346 We can't allow it to go in memory as per normal parms,
2347 because the usual place might not have the imag part
2348 adjacent to the real part. */
2349 DECL_ARTIFICIAL (p
) = addressable
;
2350 DECL_IGNORED_P (p
) = addressable
;
2351 TREE_ADDRESSABLE (p
) = 0;
2355 /* Build a second synthetic decl. */
2356 decl
= build_decl (EXPR_LOCATION (p
),
2357 PARM_DECL
, NULL_TREE
, subtype
);
2358 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2359 DECL_ARTIFICIAL (decl
) = addressable
;
2360 DECL_IGNORED_P (decl
) = addressable
;
2361 layout_decl (decl
, 0);
2362 args
->safe_insert (++i
, decl
);
2367 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2368 the hidden struct return argument, and (abi willing) complex args.
2369 Return the new parameter list. */
2372 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2374 tree fndecl
= current_function_decl
;
2375 tree fntype
= TREE_TYPE (fndecl
);
2376 vec
<tree
> fnargs
= vNULL
;
2379 for (arg
= DECL_ARGUMENTS (fndecl
); arg
; arg
= DECL_CHAIN (arg
))
2380 fnargs
.safe_push (arg
);
2382 all
->orig_fnargs
= DECL_ARGUMENTS (fndecl
);
2384 /* If struct value address is treated as the first argument, make it so. */
2385 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2386 && ! cfun
->returns_pcc_struct
2387 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2389 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2392 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2393 PARM_DECL
, get_identifier (".result_ptr"), type
);
2394 DECL_ARG_TYPE (decl
) = type
;
2395 DECL_ARTIFICIAL (decl
) = 1;
2396 DECL_NAMELESS (decl
) = 1;
2397 TREE_CONSTANT (decl
) = 1;
2398 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2399 changes, the end of the RESULT_DECL handling block in
2400 use_register_for_decl must be adjusted to match. */
2402 DECL_CHAIN (decl
) = all
->orig_fnargs
;
2403 all
->orig_fnargs
= decl
;
2404 fnargs
.safe_insert (0, decl
);
2406 all
->function_result_decl
= decl
;
2409 /* If the target wants to split complex arguments into scalars, do so. */
2410 if (targetm
.calls
.split_complex_arg
)
2411 split_complex_args (&fnargs
);
2416 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2417 data for the parameter. Incorporate ABI specifics such as pass-by-
2418 reference and type promotion. */
2421 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2422 struct assign_parm_data_one
*data
)
2426 #ifndef BROKEN_VALUE_INITIALIZATION
2427 *data
= assign_parm_data_one ();
2429 /* Old versions of GCC used to miscompile the above by only initializing
2430 the members with explicit constructors and copying garbage
2431 to the other members. */
2432 assign_parm_data_one zero_data
= {};
2436 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2438 data
->arg
.named
= 1; /* No variadic parms. */
2439 else if (DECL_CHAIN (parm
))
2440 data
->arg
.named
= 1; /* Not the last non-variadic parm. */
2441 else if (targetm
.calls
.strict_argument_naming (all
->args_so_far
))
2442 data
->arg
.named
= 1; /* Only variadic ones are unnamed. */
2444 data
->arg
.named
= 0; /* Treat as variadic. */
2446 data
->nominal_type
= TREE_TYPE (parm
);
2447 data
->arg
.type
= DECL_ARG_TYPE (parm
);
2449 /* Look out for errors propagating this far. Also, if the parameter's
2450 type is void then its value doesn't matter. */
2451 if (TREE_TYPE (parm
) == error_mark_node
2452 /* This can happen after weird syntax errors
2453 or if an enum type is defined among the parms. */
2454 || TREE_CODE (parm
) != PARM_DECL
2455 || data
->arg
.type
== NULL
2456 || VOID_TYPE_P (data
->nominal_type
))
2458 data
->nominal_type
= data
->arg
.type
= void_type_node
;
2459 data
->nominal_mode
= data
->passed_mode
= data
->arg
.mode
= VOIDmode
;
2463 /* Find mode of arg as it is passed, and mode of arg as it should be
2464 during execution of this function. */
2465 data
->passed_mode
= data
->arg
.mode
= TYPE_MODE (data
->arg
.type
);
2466 data
->nominal_mode
= TYPE_MODE (data
->nominal_type
);
2468 /* If the parm is to be passed as a transparent union or record, use the
2469 type of the first field for the tests below. We have already verified
2470 that the modes are the same. */
2471 if (RECORD_OR_UNION_TYPE_P (data
->arg
.type
)
2472 && TYPE_TRANSPARENT_AGGR (data
->arg
.type
))
2473 data
->arg
.type
= TREE_TYPE (first_field (data
->arg
.type
));
2475 /* See if this arg was passed by invisible reference. */
2476 if (apply_pass_by_reference_rules (&all
->args_so_far_v
, data
->arg
))
2478 data
->nominal_type
= data
->arg
.type
;
2479 data
->passed_mode
= data
->nominal_mode
= data
->arg
.mode
;
2482 /* Find mode as it is passed by the ABI. */
2483 unsignedp
= TYPE_UNSIGNED (data
->arg
.type
);
2485 = promote_function_mode (data
->arg
.type
, data
->arg
.mode
, &unsignedp
,
2486 TREE_TYPE (current_function_decl
), 0);
2489 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2492 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2493 struct assign_parm_data_one
*data
, bool no_rtl
)
2495 int varargs_pretend_bytes
= 0;
2497 function_arg_info last_named_arg
= data
->arg
;
2498 last_named_arg
.named
= true;
2499 targetm
.calls
.setup_incoming_varargs (all
->args_so_far
, last_named_arg
,
2500 &varargs_pretend_bytes
, no_rtl
);
2502 /* If the back-end has requested extra stack space, record how much is
2503 needed. Do not change pretend_args_size otherwise since it may be
2504 nonzero from an earlier partial argument. */
2505 if (varargs_pretend_bytes
> 0)
2506 all
->pretend_args_size
= varargs_pretend_bytes
;
2509 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2510 the incoming location of the current parameter. */
2513 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2514 struct assign_parm_data_one
*data
)
2516 HOST_WIDE_INT pretend_bytes
= 0;
2520 if (data
->arg
.mode
== VOIDmode
)
2522 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2526 targetm
.calls
.warn_parameter_passing_abi (all
->args_so_far
,
2529 entry_parm
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2531 if (entry_parm
== 0)
2532 data
->arg
.mode
= data
->passed_mode
;
2534 /* Determine parm's home in the stack, in case it arrives in the stack
2535 or we should pretend it did. Compute the stack position and rtx where
2536 the argument arrives and its size.
2538 There is one complexity here: If this was a parameter that would
2539 have been passed in registers, but wasn't only because it is
2540 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2541 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2542 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2543 as it was the previous time. */
2544 in_regs
= (entry_parm
!= 0);
2545 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2548 if (!in_regs
&& !data
->arg
.named
)
2550 if (targetm
.calls
.pretend_outgoing_varargs_named (all
->args_so_far
))
2553 function_arg_info named_arg
= data
->arg
;
2554 named_arg
.named
= true;
2555 tem
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2557 in_regs
= tem
!= NULL
;
2561 /* If this parameter was passed both in registers and in the stack, use
2562 the copy on the stack. */
2563 if (targetm
.calls
.must_pass_in_stack (data
->arg
))
2570 partial
= targetm
.calls
.arg_partial_bytes (all
->args_so_far
, data
->arg
);
2571 data
->partial
= partial
;
2573 /* The caller might already have allocated stack space for the
2574 register parameters. */
2575 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2577 /* Part of this argument is passed in registers and part
2578 is passed on the stack. Ask the prologue code to extend
2579 the stack part so that we can recreate the full value.
2581 PRETEND_BYTES is the size of the registers we need to store.
2582 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2583 stack space that the prologue should allocate.
2585 Internally, gcc assumes that the argument pointer is aligned
2586 to STACK_BOUNDARY bits. This is used both for alignment
2587 optimizations (see init_emit) and to locate arguments that are
2588 aligned to more than PARM_BOUNDARY bits. We must preserve this
2589 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2590 a stack boundary. */
2592 /* We assume at most one partial arg, and it must be the first
2593 argument on the stack. */
2594 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2596 pretend_bytes
= partial
;
2597 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2599 /* We want to align relative to the actual stack pointer, so
2600 don't include this in the stack size until later. */
2601 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2605 locate_and_pad_parm (data
->arg
.mode
, data
->arg
.type
, in_regs
,
2606 all
->reg_parm_stack_space
,
2607 entry_parm
? data
->partial
: 0, current_function_decl
,
2608 &all
->stack_args_size
, &data
->locate
);
2610 /* Update parm_stack_boundary if this parameter is passed in the
2612 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2613 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2615 /* Adjust offsets to include the pretend args. */
2616 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2617 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2618 data
->locate
.offset
.constant
+= pretend_bytes
;
2620 data
->entry_parm
= entry_parm
;
2623 /* A subroutine of assign_parms. If there is actually space on the stack
2624 for this parm, count it in stack_args_size and return true. */
2627 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2628 struct assign_parm_data_one
*data
)
2630 /* Trivially true if we've no incoming register. */
2631 if (data
->entry_parm
== NULL
)
2633 /* Also true if we're partially in registers and partially not,
2634 since we've arranged to drop the entire argument on the stack. */
2635 else if (data
->partial
!= 0)
2637 /* Also true if the target says that it's passed in both registers
2638 and on the stack. */
2639 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2640 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2642 /* Also true if the target says that there's stack allocated for
2643 all register parameters. */
2644 else if (all
->reg_parm_stack_space
> 0)
2646 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2650 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2651 if (data
->locate
.size
.var
)
2652 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2657 /* A subroutine of assign_parms. Given that this parameter is allocated
2658 stack space by the ABI, find it. */
2661 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2663 rtx offset_rtx
, stack_parm
;
2664 unsigned int align
, boundary
;
2666 /* If we're passing this arg using a reg, make its stack home the
2667 aligned stack slot. */
2668 if (data
->entry_parm
)
2669 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2671 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2673 stack_parm
= crtl
->args
.internal_arg_pointer
;
2674 if (offset_rtx
!= const0_rtx
)
2675 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2676 stack_parm
= gen_rtx_MEM (data
->arg
.mode
, stack_parm
);
2678 if (!data
->arg
.pass_by_reference
)
2680 set_mem_attributes (stack_parm
, parm
, 1);
2681 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2682 while promoted mode's size is needed. */
2683 if (data
->arg
.mode
!= BLKmode
2684 && data
->arg
.mode
!= DECL_MODE (parm
))
2686 set_mem_size (stack_parm
, GET_MODE_SIZE (data
->arg
.mode
));
2687 if (MEM_EXPR (stack_parm
) && MEM_OFFSET_KNOWN_P (stack_parm
))
2689 poly_int64 offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2691 if (maybe_ne (offset
, 0))
2692 set_mem_offset (stack_parm
, MEM_OFFSET (stack_parm
) - offset
);
2697 boundary
= data
->locate
.boundary
;
2698 align
= BITS_PER_UNIT
;
2700 /* If we're padding upward, we know that the alignment of the slot
2701 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2702 intentionally forcing upward padding. Otherwise we have to come
2703 up with a guess at the alignment based on OFFSET_RTX. */
2705 if (data
->locate
.where_pad
== PAD_NONE
|| data
->entry_parm
)
2707 else if (data
->locate
.where_pad
== PAD_UPWARD
)
2710 /* If the argument offset is actually more aligned than the nominal
2711 stack slot boundary, take advantage of that excess alignment.
2712 Don't make any assumptions if STACK_POINTER_OFFSET is in use. */
2713 if (poly_int_rtx_p (offset_rtx
, &offset
)
2714 && known_eq (STACK_POINTER_OFFSET
, 0))
2716 unsigned int offset_align
= known_alignment (offset
) * BITS_PER_UNIT
;
2717 if (offset_align
== 0 || offset_align
> STACK_BOUNDARY
)
2718 offset_align
= STACK_BOUNDARY
;
2719 align
= MAX (align
, offset_align
);
2722 else if (poly_int_rtx_p (offset_rtx
, &offset
))
2724 align
= least_bit_hwi (boundary
);
2725 unsigned int offset_align
= known_alignment (offset
) * BITS_PER_UNIT
;
2726 if (offset_align
!= 0)
2727 align
= MIN (align
, offset_align
);
2729 set_mem_align (stack_parm
, align
);
2731 if (data
->entry_parm
)
2732 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2734 data
->stack_parm
= stack_parm
;
2737 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2738 always valid and contiguous. */
2741 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2743 rtx entry_parm
= data
->entry_parm
;
2744 rtx stack_parm
= data
->stack_parm
;
2746 /* If this parm was passed part in regs and part in memory, pretend it
2747 arrived entirely in memory by pushing the register-part onto the stack.
2748 In the special case of a DImode or DFmode that is split, we could put
2749 it together in a pseudoreg directly, but for now that's not worth
2751 if (data
->partial
!= 0)
2753 /* Handle calls that pass values in multiple non-contiguous
2754 locations. The Irix 6 ABI has examples of this. */
2755 if (GET_CODE (entry_parm
) == PARALLEL
)
2756 emit_group_store (validize_mem (copy_rtx (stack_parm
)), entry_parm
,
2757 data
->arg
.type
, int_size_in_bytes (data
->arg
.type
));
2760 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2761 move_block_from_reg (REGNO (entry_parm
),
2762 validize_mem (copy_rtx (stack_parm
)),
2763 data
->partial
/ UNITS_PER_WORD
);
2766 entry_parm
= stack_parm
;
2769 /* If we didn't decide this parm came in a register, by default it came
2771 else if (entry_parm
== NULL
)
2772 entry_parm
= stack_parm
;
2774 /* When an argument is passed in multiple locations, we can't make use
2775 of this information, but we can save some copying if the whole argument
2776 is passed in a single register. */
2777 else if (GET_CODE (entry_parm
) == PARALLEL
2778 && data
->nominal_mode
!= BLKmode
2779 && data
->passed_mode
!= BLKmode
)
2781 size_t i
, len
= XVECLEN (entry_parm
, 0);
2783 for (i
= 0; i
< len
; i
++)
2784 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2785 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2786 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2787 == data
->passed_mode
)
2788 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2790 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2795 data
->entry_parm
= entry_parm
;
2798 /* A subroutine of assign_parms. Reconstitute any values which were
2799 passed in multiple registers and would fit in a single register. */
2802 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2804 rtx entry_parm
= data
->entry_parm
;
2806 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2807 This can be done with register operations rather than on the
2808 stack, even if we will store the reconstituted parameter on the
2810 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2812 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2813 emit_group_store (parmreg
, entry_parm
, data
->arg
.type
,
2814 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2815 entry_parm
= parmreg
;
2818 data
->entry_parm
= entry_parm
;
2821 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2822 always valid and properly aligned. */
2825 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2827 rtx stack_parm
= data
->stack_parm
;
2829 /* If we can't trust the parm stack slot to be aligned enough for its
2830 ultimate type, don't use that slot after entry. We'll make another
2831 stack slot, if we need one. */
2833 && ((GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
)
2834 && ((optab_handler (movmisalign_optab
, data
->nominal_mode
)
2835 != CODE_FOR_nothing
)
2836 || targetm
.slow_unaligned_access (data
->nominal_mode
,
2837 MEM_ALIGN (stack_parm
))))
2838 || (data
->nominal_type
2839 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2840 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2843 /* If parm was passed in memory, and we need to convert it on entry,
2844 don't store it back in that same slot. */
2845 else if (data
->entry_parm
== stack_parm
2846 && data
->nominal_mode
!= BLKmode
2847 && data
->nominal_mode
!= data
->passed_mode
)
2850 /* If stack protection is in effect for this function, don't leave any
2851 pointers in their passed stack slots. */
2852 else if (crtl
->stack_protect_guard
2853 && (flag_stack_protect
== SPCT_FLAG_ALL
2854 || data
->arg
.pass_by_reference
2855 || POINTER_TYPE_P (data
->nominal_type
)))
2858 data
->stack_parm
= stack_parm
;
2861 /* A subroutine of assign_parms. Return true if the current parameter
2862 should be stored as a BLKmode in the current frame. */
2865 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2867 if (data
->nominal_mode
== BLKmode
)
2869 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2872 #ifdef BLOCK_REG_PADDING
2873 /* Only assign_parm_setup_block knows how to deal with register arguments
2874 that are padded at the least significant end. */
2875 if (REG_P (data
->entry_parm
)
2876 && known_lt (GET_MODE_SIZE (data
->arg
.mode
), UNITS_PER_WORD
)
2877 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->arg
.type
, 1)
2878 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
2885 /* A subroutine of assign_parms. Arrange for the parameter to be
2886 present and valid in DATA->STACK_RTL. */
2889 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2890 tree parm
, struct assign_parm_data_one
*data
)
2892 rtx entry_parm
= data
->entry_parm
;
2893 rtx stack_parm
= data
->stack_parm
;
2894 rtx target_reg
= NULL_RTX
;
2895 bool in_conversion_seq
= false;
2897 HOST_WIDE_INT size_stored
;
2899 if (GET_CODE (entry_parm
) == PARALLEL
)
2900 entry_parm
= emit_group_move_into_temps (entry_parm
);
2902 /* If we want the parameter in a pseudo, don't use a stack slot. */
2903 if (is_gimple_reg (parm
) && use_register_for_decl (parm
))
2905 tree def
= ssa_default_def (cfun
, parm
);
2907 machine_mode mode
= promote_ssa_mode (def
, NULL
);
2908 rtx reg
= gen_reg_rtx (mode
);
2909 if (GET_CODE (reg
) != CONCAT
)
2914 /* Avoid allocating a stack slot, if there isn't one
2915 preallocated by the ABI. It might seem like we should
2916 always prefer a pseudo, but converting between
2917 floating-point and integer modes goes through the stack
2918 on various machines, so it's better to use the reserved
2919 stack slot than to risk wasting it and allocating more
2920 for the conversion. */
2921 if (stack_parm
== NULL_RTX
)
2923 int save
= generating_concat_p
;
2924 generating_concat_p
= 0;
2925 stack_parm
= gen_reg_rtx (mode
);
2926 generating_concat_p
= save
;
2929 data
->stack_parm
= NULL
;
2932 size
= int_size_in_bytes (data
->arg
.type
);
2933 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2934 if (stack_parm
== 0)
2936 HOST_WIDE_INT parm_align
2938 ? MAX (DECL_ALIGN (parm
), BITS_PER_WORD
) : DECL_ALIGN (parm
));
2940 SET_DECL_ALIGN (parm
, parm_align
);
2941 if (DECL_ALIGN (parm
) > MAX_SUPPORTED_STACK_ALIGNMENT
)
2943 rtx allocsize
= gen_int_mode (size_stored
, Pmode
);
2944 get_dynamic_stack_size (&allocsize
, 0, DECL_ALIGN (parm
), NULL
);
2945 stack_parm
= assign_stack_local (BLKmode
, UINTVAL (allocsize
),
2946 MAX_SUPPORTED_STACK_ALIGNMENT
);
2947 rtx addr
= align_dynamic_address (XEXP (stack_parm
, 0),
2949 mark_reg_pointer (addr
, DECL_ALIGN (parm
));
2950 stack_parm
= gen_rtx_MEM (GET_MODE (stack_parm
), addr
);
2951 MEM_NOTRAP_P (stack_parm
) = 1;
2954 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2956 if (known_eq (GET_MODE_SIZE (GET_MODE (entry_parm
)), size
))
2957 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2958 set_mem_attributes (stack_parm
, parm
, 1);
2961 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2962 calls that pass values in multiple non-contiguous locations. */
2963 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2967 /* Note that we will be storing an integral number of words.
2968 So we have to be careful to ensure that we allocate an
2969 integral number of words. We do this above when we call
2970 assign_stack_local if space was not allocated in the argument
2971 list. If it was, this will not work if PARM_BOUNDARY is not
2972 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2973 if it becomes a problem. Exception is when BLKmode arrives
2974 with arguments not conforming to word_mode. */
2976 if (data
->stack_parm
== 0)
2978 else if (GET_CODE (entry_parm
) == PARALLEL
)
2981 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2983 mem
= validize_mem (copy_rtx (stack_parm
));
2985 /* Handle values in multiple non-contiguous locations. */
2986 if (GET_CODE (entry_parm
) == PARALLEL
&& !MEM_P (mem
))
2987 emit_group_store (mem
, entry_parm
, data
->arg
.type
, size
);
2988 else if (GET_CODE (entry_parm
) == PARALLEL
)
2990 push_to_sequence2 (all
->first_conversion_insn
,
2991 all
->last_conversion_insn
);
2992 emit_group_store (mem
, entry_parm
, data
->arg
.type
, size
);
2993 all
->first_conversion_insn
= get_insns ();
2994 all
->last_conversion_insn
= get_last_insn ();
2996 in_conversion_seq
= true;
3002 /* If SIZE is that of a mode no bigger than a word, just use
3003 that mode's store operation. */
3004 else if (size
<= UNITS_PER_WORD
)
3006 unsigned int bits
= size
* BITS_PER_UNIT
;
3007 machine_mode mode
= int_mode_for_size (bits
, 0).else_blk ();
3010 #ifdef BLOCK_REG_PADDING
3011 && (size
== UNITS_PER_WORD
3012 || (BLOCK_REG_PADDING (mode
, data
->arg
.type
, 1)
3013 != (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
3019 /* We are really truncating a word_mode value containing
3020 SIZE bytes into a value of mode MODE. If such an
3021 operation requires no actual instructions, we can refer
3022 to the value directly in mode MODE, otherwise we must
3023 start with the register in word_mode and explicitly
3025 if (mode
== word_mode
3026 || TRULY_NOOP_TRUNCATION_MODES_P (mode
, word_mode
))
3027 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
3030 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3031 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
3033 emit_move_insn (change_address (mem
, mode
, 0), reg
);
3036 #ifdef BLOCK_REG_PADDING
3037 /* Storing the register in memory as a full word, as
3038 move_block_from_reg below would do, and then using the
3039 MEM in a smaller mode, has the effect of shifting right
3040 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3041 shifting must be explicit. */
3042 else if (!MEM_P (mem
))
3046 /* If the assert below fails, we should have taken the
3047 mode != BLKmode path above, unless we have downward
3048 padding of smaller-than-word arguments on a machine
3049 with little-endian bytes, which would likely require
3050 additional changes to work correctly. */
3051 gcc_checking_assert (BYTES_BIG_ENDIAN
3052 && (BLOCK_REG_PADDING (mode
,
3056 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3058 x
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3059 x
= expand_shift (RSHIFT_EXPR
, word_mode
, x
, by
,
3061 x
= force_reg (word_mode
, x
);
3062 x
= gen_lowpart_SUBREG (GET_MODE (mem
), x
);
3064 emit_move_insn (mem
, x
);
3068 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3069 machine must be aligned to the left before storing
3070 to memory. Note that the previous test doesn't
3071 handle all cases (e.g. SIZE == 3). */
3072 else if (size
!= UNITS_PER_WORD
3073 #ifdef BLOCK_REG_PADDING
3074 && (BLOCK_REG_PADDING (mode
, data
->arg
.type
, 1)
3082 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3083 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3085 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, by
, NULL_RTX
, 1);
3086 tem
= change_address (mem
, word_mode
, 0);
3087 emit_move_insn (tem
, x
);
3090 move_block_from_reg (REGNO (entry_parm
), mem
,
3091 size_stored
/ UNITS_PER_WORD
);
3093 else if (!MEM_P (mem
))
3095 gcc_checking_assert (size
> UNITS_PER_WORD
);
3096 #ifdef BLOCK_REG_PADDING
3097 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem
),
3101 emit_move_insn (mem
, entry_parm
);
3104 move_block_from_reg (REGNO (entry_parm
), mem
,
3105 size_stored
/ UNITS_PER_WORD
);
3107 else if (data
->stack_parm
== 0 && !TYPE_EMPTY_P (data
->arg
.type
))
3109 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3110 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
3112 all
->first_conversion_insn
= get_insns ();
3113 all
->last_conversion_insn
= get_last_insn ();
3115 in_conversion_seq
= true;
3120 if (!in_conversion_seq
)
3121 emit_move_insn (target_reg
, stack_parm
);
3124 push_to_sequence2 (all
->first_conversion_insn
,
3125 all
->last_conversion_insn
);
3126 emit_move_insn (target_reg
, stack_parm
);
3127 all
->first_conversion_insn
= get_insns ();
3128 all
->last_conversion_insn
= get_last_insn ();
3131 stack_parm
= target_reg
;
3134 data
->stack_parm
= stack_parm
;
3135 set_parm_rtl (parm
, stack_parm
);
3138 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3139 parameter. Get it there. Perform all ABI specified conversions. */
3142 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
3143 struct assign_parm_data_one
*data
)
3145 rtx parmreg
, validated_mem
;
3146 rtx equiv_stack_parm
;
3147 machine_mode promoted_nominal_mode
;
3148 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3149 bool did_conversion
= false;
3150 bool need_conversion
, moved
;
3151 enum insn_code icode
;
3154 /* Store the parm in a pseudoregister during the function, but we may
3155 need to do it in a wider mode. Using 2 here makes the result
3156 consistent with promote_decl_mode and thus expand_expr_real_1. */
3157 promoted_nominal_mode
3158 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
3159 TREE_TYPE (current_function_decl
), 2);
3161 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
3162 if (!DECL_ARTIFICIAL (parm
))
3163 mark_user_reg (parmreg
);
3165 /* If this was an item that we received a pointer to,
3166 set rtl appropriately. */
3167 if (data
->arg
.pass_by_reference
)
3169 rtl
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->arg
.type
)), parmreg
);
3170 set_mem_attributes (rtl
, parm
, 1);
3175 assign_parm_remove_parallels (data
);
3177 /* Copy the value into the register, thus bridging between
3178 assign_parm_find_data_types and expand_expr_real_1. */
3180 equiv_stack_parm
= data
->stack_parm
;
3181 validated_mem
= validize_mem (copy_rtx (data
->entry_parm
));
3183 need_conversion
= (data
->nominal_mode
!= data
->passed_mode
3184 || promoted_nominal_mode
!= data
->arg
.mode
);
3188 && GET_MODE_CLASS (data
->nominal_mode
) == MODE_INT
3189 && data
->nominal_mode
== data
->passed_mode
3190 && data
->nominal_mode
== GET_MODE (data
->entry_parm
))
3192 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3193 mode, by the caller. We now have to convert it to
3194 NOMINAL_MODE, if different. However, PARMREG may be in
3195 a different mode than NOMINAL_MODE if it is being stored
3198 If ENTRY_PARM is a hard register, it might be in a register
3199 not valid for operating in its mode (e.g., an odd-numbered
3200 register for a DFmode). In that case, moves are the only
3201 thing valid, so we can't do a convert from there. This
3202 occurs when the calling sequence allow such misaligned
3205 In addition, the conversion may involve a call, which could
3206 clobber parameters which haven't been copied to pseudo
3209 First, we try to emit an insn which performs the necessary
3210 conversion. We verify that this insn does not clobber any
3215 icode
= can_extend_p (promoted_nominal_mode
, data
->passed_mode
,
3219 op1
= validated_mem
;
3220 if (icode
!= CODE_FOR_nothing
3221 && insn_operand_matches (icode
, 0, op0
)
3222 && insn_operand_matches (icode
, 1, op1
))
3224 enum rtx_code code
= unsignedp
? ZERO_EXTEND
: SIGN_EXTEND
;
3225 rtx_insn
*insn
, *insns
;
3227 HARD_REG_SET hardregs
;
3230 /* If op1 is a hard register that is likely spilled, first
3231 force it into a pseudo, otherwise combiner might extend
3232 its lifetime too much. */
3233 if (GET_CODE (t
) == SUBREG
)
3236 && HARD_REGISTER_P (t
)
3237 && ! TEST_HARD_REG_BIT (fixed_reg_set
, REGNO (t
))
3238 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t
))))
3240 t
= gen_reg_rtx (GET_MODE (op1
));
3241 emit_move_insn (t
, op1
);
3245 rtx_insn
*pat
= gen_extend_insn (op0
, t
, promoted_nominal_mode
,
3246 data
->passed_mode
, unsignedp
);
3248 insns
= get_insns ();
3251 CLEAR_HARD_REG_SET (hardregs
);
3252 for (insn
= insns
; insn
&& moved
; insn
= NEXT_INSN (insn
))
3255 note_stores (insn
, record_hard_reg_sets
, &hardregs
);
3256 if (!hard_reg_set_empty_p (hardregs
))
3265 if (equiv_stack_parm
!= NULL_RTX
)
3266 equiv_stack_parm
= gen_rtx_fmt_e (code
, GET_MODE (parmreg
),
3273 /* Nothing to do. */
3275 else if (need_conversion
)
3277 /* We did not have an insn to convert directly, or the sequence
3278 generated appeared unsafe. We must first copy the parm to a
3279 pseudo reg, and save the conversion until after all
3280 parameters have been moved. */
3283 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3285 emit_move_insn (tempreg
, validated_mem
);
3287 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3288 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
3290 if (partial_subreg_p (tempreg
)
3291 && GET_MODE (tempreg
) == data
->nominal_mode
3292 && REG_P (SUBREG_REG (tempreg
))
3293 && data
->nominal_mode
== data
->passed_mode
3294 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
))
3296 /* The argument is already sign/zero extended, so note it
3298 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
3299 SUBREG_PROMOTED_SET (tempreg
, unsignedp
);
3302 /* TREE_USED gets set erroneously during expand_assignment. */
3303 save_tree_used
= TREE_USED (parm
);
3304 SET_DECL_RTL (parm
, rtl
);
3305 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
3306 SET_DECL_RTL (parm
, NULL_RTX
);
3307 TREE_USED (parm
) = save_tree_used
;
3308 all
->first_conversion_insn
= get_insns ();
3309 all
->last_conversion_insn
= get_last_insn ();
3312 did_conversion
= true;
3314 else if (MEM_P (data
->entry_parm
)
3315 && GET_MODE_ALIGNMENT (promoted_nominal_mode
)
3316 > MEM_ALIGN (data
->entry_parm
)
3317 && (((icode
= optab_handler (movmisalign_optab
,
3318 promoted_nominal_mode
))
3319 != CODE_FOR_nothing
)
3320 || targetm
.slow_unaligned_access (promoted_nominal_mode
,
3321 MEM_ALIGN (data
->entry_parm
))))
3323 if (icode
!= CODE_FOR_nothing
)
3324 emit_insn (GEN_FCN (icode
) (parmreg
, validated_mem
));
3326 rtl
= parmreg
= extract_bit_field (validated_mem
,
3327 GET_MODE_BITSIZE (promoted_nominal_mode
), 0,
3329 promoted_nominal_mode
, VOIDmode
, false, NULL
);
3332 emit_move_insn (parmreg
, validated_mem
);
3334 /* If we were passed a pointer but the actual value can live in a register,
3335 retrieve it and use it directly. Note that we cannot use nominal_mode,
3336 because it will have been set to Pmode above, we must use the actual mode
3337 of the parameter instead. */
3338 if (data
->arg
.pass_by_reference
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
)
3340 /* Use a stack slot for debugging purposes if possible. */
3341 if (use_register_for_decl (parm
))
3343 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
3344 mark_user_reg (parmreg
);
3348 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3349 TYPE_MODE (TREE_TYPE (parm
)),
3350 TYPE_ALIGN (TREE_TYPE (parm
)));
3352 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm
)),
3353 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm
))),
3355 set_mem_attributes (parmreg
, parm
, 1);
3358 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3359 the debug info in case it is not legitimate. */
3360 if (GET_MODE (parmreg
) != GET_MODE (rtl
))
3362 rtx tempreg
= gen_reg_rtx (GET_MODE (rtl
));
3363 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3365 push_to_sequence2 (all
->first_conversion_insn
,
3366 all
->last_conversion_insn
);
3367 emit_move_insn (tempreg
, rtl
);
3368 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
3369 emit_move_insn (MEM_P (parmreg
) ? copy_rtx (parmreg
) : parmreg
,
3371 all
->first_conversion_insn
= get_insns ();
3372 all
->last_conversion_insn
= get_last_insn ();
3375 did_conversion
= true;
3378 emit_move_insn (MEM_P (parmreg
) ? copy_rtx (parmreg
) : parmreg
, rtl
);
3382 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3384 data
->stack_parm
= NULL
;
3387 set_parm_rtl (parm
, rtl
);
3389 /* Mark the register as eliminable if we did no conversion and it was
3390 copied from memory at a fixed offset, and the arg pointer was not
3391 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3392 offset formed an invalid address, such memory-equivalences as we
3393 make here would screw up life analysis for it. */
3394 if (data
->nominal_mode
== data
->passed_mode
3396 && data
->stack_parm
!= 0
3397 && MEM_P (data
->stack_parm
)
3398 && data
->locate
.offset
.var
== 0
3399 && reg_mentioned_p (virtual_incoming_args_rtx
,
3400 XEXP (data
->stack_parm
, 0)))
3402 rtx_insn
*linsn
= get_last_insn ();
3406 /* Mark complex types separately. */
3407 if (GET_CODE (parmreg
) == CONCAT
)
3409 scalar_mode submode
= GET_MODE_INNER (GET_MODE (parmreg
));
3410 int regnor
= REGNO (XEXP (parmreg
, 0));
3411 int regnoi
= REGNO (XEXP (parmreg
, 1));
3412 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
3413 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
3414 GET_MODE_SIZE (submode
));
3416 /* Scan backwards for the set of the real and
3418 for (sinsn
= linsn
; sinsn
!= 0;
3419 sinsn
= prev_nonnote_insn (sinsn
))
3421 set
= single_set (sinsn
);
3425 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
3426 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
3427 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
3428 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
3432 set_dst_reg_note (linsn
, REG_EQUIV
, equiv_stack_parm
, parmreg
);
3435 /* For pointer data type, suggest pointer register. */
3436 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
3437 mark_reg_pointer (parmreg
,
3438 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
3441 /* A subroutine of assign_parms. Allocate stack space to hold the current
3442 parameter. Get it there. Perform all ABI specified conversions. */
3445 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
3446 struct assign_parm_data_one
*data
)
3448 /* Value must be stored in the stack slot STACK_PARM during function
3450 bool to_conversion
= false;
3452 assign_parm_remove_parallels (data
);
3454 if (data
->arg
.mode
!= data
->nominal_mode
)
3456 /* Conversion is required. */
3457 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3459 emit_move_insn (tempreg
, validize_mem (copy_rtx (data
->entry_parm
)));
3461 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3462 to_conversion
= true;
3464 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
3465 TYPE_UNSIGNED (TREE_TYPE (parm
)));
3467 if (data
->stack_parm
)
3470 = subreg_lowpart_offset (data
->nominal_mode
,
3471 GET_MODE (data
->stack_parm
));
3472 /* ??? This may need a big-endian conversion on sparc64. */
3474 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
3475 if (maybe_ne (offset
, 0) && MEM_OFFSET_KNOWN_P (data
->stack_parm
))
3476 set_mem_offset (data
->stack_parm
,
3477 MEM_OFFSET (data
->stack_parm
) + offset
);
3481 if (data
->entry_parm
!= data
->stack_parm
)
3485 if (data
->stack_parm
== 0)
3487 int align
= STACK_SLOT_ALIGNMENT (data
->arg
.type
,
3488 GET_MODE (data
->entry_parm
),
3489 TYPE_ALIGN (data
->arg
.type
));
3490 if (align
< (int)GET_MODE_ALIGNMENT (GET_MODE (data
->entry_parm
))
3491 && ((optab_handler (movmisalign_optab
,
3492 GET_MODE (data
->entry_parm
))
3493 != CODE_FOR_nothing
)
3494 || targetm
.slow_unaligned_access (GET_MODE (data
->entry_parm
),
3496 align
= GET_MODE_ALIGNMENT (GET_MODE (data
->entry_parm
));
3498 = assign_stack_local (GET_MODE (data
->entry_parm
),
3499 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3501 align
= MEM_ALIGN (data
->stack_parm
);
3502 set_mem_attributes (data
->stack_parm
, parm
, 1);
3503 set_mem_align (data
->stack_parm
, align
);
3506 dest
= validize_mem (copy_rtx (data
->stack_parm
));
3507 src
= validize_mem (copy_rtx (data
->entry_parm
));
3509 if (TYPE_EMPTY_P (data
->arg
.type
))
3510 /* Empty types don't really need to be copied. */;
3511 else if (MEM_P (src
))
3513 /* Use a block move to handle potentially misaligned entry_parm. */
3515 push_to_sequence2 (all
->first_conversion_insn
,
3516 all
->last_conversion_insn
);
3517 to_conversion
= true;
3519 emit_block_move (dest
, src
,
3520 GEN_INT (int_size_in_bytes (data
->arg
.type
)),
3526 src
= force_reg (GET_MODE (src
), src
);
3527 emit_move_insn (dest
, src
);
3533 all
->first_conversion_insn
= get_insns ();
3534 all
->last_conversion_insn
= get_last_insn ();
3538 set_parm_rtl (parm
, data
->stack_parm
);
3541 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3542 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3545 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
,
3549 tree orig_fnargs
= all
->orig_fnargs
;
3552 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
), ++i
)
3554 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3555 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3557 rtx tmp
, real
, imag
;
3558 scalar_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3560 real
= DECL_RTL (fnargs
[i
]);
3561 imag
= DECL_RTL (fnargs
[i
+ 1]);
3562 if (inner
!= GET_MODE (real
))
3564 real
= gen_lowpart_SUBREG (inner
, real
);
3565 imag
= gen_lowpart_SUBREG (inner
, imag
);
3568 if (TREE_ADDRESSABLE (parm
))
3571 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3572 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3574 TYPE_ALIGN (TREE_TYPE (parm
)));
3576 /* split_complex_arg put the real and imag parts in
3577 pseudos. Move them to memory. */
3578 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3579 set_mem_attributes (tmp
, parm
, 1);
3580 rmem
= adjust_address_nv (tmp
, inner
, 0);
3581 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3582 push_to_sequence2 (all
->first_conversion_insn
,
3583 all
->last_conversion_insn
);
3584 emit_move_insn (rmem
, real
);
3585 emit_move_insn (imem
, imag
);
3586 all
->first_conversion_insn
= get_insns ();
3587 all
->last_conversion_insn
= get_last_insn ();
3591 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3592 set_parm_rtl (parm
, tmp
);
3594 real
= DECL_INCOMING_RTL (fnargs
[i
]);
3595 imag
= DECL_INCOMING_RTL (fnargs
[i
+ 1]);
3596 if (inner
!= GET_MODE (real
))
3598 real
= gen_lowpart_SUBREG (inner
, real
);
3599 imag
= gen_lowpart_SUBREG (inner
, imag
);
3601 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3602 set_decl_incoming_rtl (parm
, tmp
, false);
3608 /* Assign RTL expressions to the function's parameters. This may involve
3609 copying them into registers and using those registers as the DECL_RTL. */
3612 assign_parms (tree fndecl
)
3614 struct assign_parm_data_all all
;
3619 crtl
->args
.internal_arg_pointer
3620 = targetm
.calls
.internal_arg_pointer ();
3622 assign_parms_initialize_all (&all
);
3623 fnargs
= assign_parms_augmented_arg_list (&all
);
3625 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3627 struct assign_parm_data_one data
;
3629 /* Extract the type of PARM; adjust it according to ABI. */
3630 assign_parm_find_data_types (&all
, parm
, &data
);
3632 /* Early out for errors and void parameters. */
3633 if (data
.passed_mode
== VOIDmode
)
3635 SET_DECL_RTL (parm
, const0_rtx
);
3636 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3640 /* Estimate stack alignment from parameter alignment. */
3641 if (SUPPORTS_STACK_ALIGNMENT
)
3644 = targetm
.calls
.function_arg_boundary (data
.arg
.mode
,
3646 align
= MINIMUM_ALIGNMENT (data
.arg
.type
, data
.arg
.mode
, align
);
3647 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3648 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3649 TYPE_MODE (data
.nominal_type
),
3650 TYPE_ALIGN (data
.nominal_type
));
3651 if (crtl
->stack_alignment_estimated
< align
)
3653 gcc_assert (!crtl
->stack_realign_processed
);
3654 crtl
->stack_alignment_estimated
= align
;
3658 /* Find out where the parameter arrives in this function. */
3659 assign_parm_find_entry_rtl (&all
, &data
);
3661 /* Find out where stack space for this parameter might be. */
3662 if (assign_parm_is_stack_parm (&all
, &data
))
3664 assign_parm_find_stack_rtl (parm
, &data
);
3665 assign_parm_adjust_entry_rtl (&data
);
3666 /* For arguments that occupy no space in the parameter
3667 passing area, have non-zero size and have address taken,
3668 force creation of a stack slot so that they have distinct
3669 address from other parameters. */
3670 if (TYPE_EMPTY_P (data
.arg
.type
)
3671 && TREE_ADDRESSABLE (parm
)
3672 && data
.entry_parm
== data
.stack_parm
3673 && MEM_P (data
.entry_parm
)
3674 && int_size_in_bytes (data
.arg
.type
))
3675 data
.stack_parm
= NULL_RTX
;
3677 /* Record permanently how this parm was passed. */
3678 if (data
.arg
.pass_by_reference
)
3681 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
.arg
.type
)),
3683 set_decl_incoming_rtl (parm
, incoming_rtl
, true);
3686 set_decl_incoming_rtl (parm
, data
.entry_parm
, false);
3688 assign_parm_adjust_stack_rtl (&data
);
3690 if (assign_parm_setup_block_p (&data
))
3691 assign_parm_setup_block (&all
, parm
, &data
);
3692 else if (data
.arg
.pass_by_reference
|| use_register_for_decl (parm
))
3693 assign_parm_setup_reg (&all
, parm
, &data
);
3695 assign_parm_setup_stack (&all
, parm
, &data
);
3697 if (cfun
->stdarg
&& !DECL_CHAIN (parm
))
3698 assign_parms_setup_varargs (&all
, &data
, false);
3700 /* Update info on where next arg arrives in registers. */
3701 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.arg
);
3704 if (targetm
.calls
.split_complex_arg
)
3705 assign_parms_unsplit_complex (&all
, fnargs
);
3709 /* Output all parameter conversion instructions (possibly including calls)
3710 now that all parameters have been copied out of hard registers. */
3711 emit_insn (all
.first_conversion_insn
);
3713 /* Estimate reload stack alignment from scalar return mode. */
3714 if (SUPPORTS_STACK_ALIGNMENT
)
3716 if (DECL_RESULT (fndecl
))
3718 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3719 machine_mode mode
= TYPE_MODE (type
);
3723 && !AGGREGATE_TYPE_P (type
))
3725 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3726 if (crtl
->stack_alignment_estimated
< align
)
3728 gcc_assert (!crtl
->stack_realign_processed
);
3729 crtl
->stack_alignment_estimated
= align
;
3735 /* If we are receiving a struct value address as the first argument, set up
3736 the RTL for the function result. As this might require code to convert
3737 the transmitted address to Pmode, we do this here to ensure that possible
3738 preliminary conversions of the address have been emitted already. */
3739 if (all
.function_result_decl
)
3741 tree result
= DECL_RESULT (current_function_decl
);
3742 rtx addr
= DECL_RTL (all
.function_result_decl
);
3745 if (DECL_BY_REFERENCE (result
))
3747 SET_DECL_VALUE_EXPR (result
, all
.function_result_decl
);
3752 SET_DECL_VALUE_EXPR (result
,
3753 build1 (INDIRECT_REF
, TREE_TYPE (result
),
3754 all
.function_result_decl
));
3755 addr
= convert_memory_address (Pmode
, addr
);
3756 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3757 set_mem_attributes (x
, result
, 1);
3760 DECL_HAS_VALUE_EXPR_P (result
) = 1;
3762 set_parm_rtl (result
, x
);
3765 /* We have aligned all the args, so add space for the pretend args. */
3766 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3767 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3768 crtl
->args
.size
= all
.stack_args_size
.constant
;
3770 /* Adjust function incoming argument size for alignment and
3773 crtl
->args
.size
= upper_bound (crtl
->args
.size
, all
.reg_parm_stack_space
);
3774 crtl
->args
.size
= aligned_upper_bound (crtl
->args
.size
,
3775 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3777 if (ARGS_GROW_DOWNWARD
)
3779 crtl
->args
.arg_offset_rtx
3780 = (all
.stack_args_size
.var
== 0
3781 ? gen_int_mode (-all
.stack_args_size
.constant
, Pmode
)
3782 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3783 size_int (-all
.stack_args_size
.constant
)),
3784 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3787 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3789 /* See how many bytes, if any, of its args a function should try to pop
3792 crtl
->args
.pops_args
= targetm
.calls
.return_pops_args (fndecl
,
3796 /* For stdarg.h function, save info about
3797 regs and stack space used by the named args. */
3799 crtl
->args
.info
= all
.args_so_far_v
;
3801 /* Set the rtx used for the function return value. Put this in its
3802 own variable so any optimizers that need this information don't have
3803 to include tree.h. Do this here so it gets done when an inlined
3804 function gets output. */
3807 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3808 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3810 /* If scalar return value was computed in a pseudo-reg, or was a named
3811 return value that got dumped to the stack, copy that to the hard
3813 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3815 tree decl_result
= DECL_RESULT (fndecl
);
3816 rtx decl_rtl
= DECL_RTL (decl_result
);
3818 if (REG_P (decl_rtl
)
3819 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3820 : DECL_REGISTER (decl_result
))
3824 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3826 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3827 /* The delay slot scheduler assumes that crtl->return_rtx
3828 holds the hard register containing the return value, not a
3829 temporary pseudo. */
3830 crtl
->return_rtx
= real_decl_rtl
;
3835 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3836 For all seen types, gimplify their sizes. */
3839 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3846 if (POINTER_TYPE_P (t
))
3848 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3849 && !TYPE_SIZES_GIMPLIFIED (t
))
3851 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3859 /* Gimplify the parameter list for current_function_decl. This involves
3860 evaluating SAVE_EXPRs of variable sized parameters and generating code
3861 to implement callee-copies reference parameters. Returns a sequence of
3862 statements to add to the beginning of the function. */
3865 gimplify_parameters (gimple_seq
*cleanup
)
3867 struct assign_parm_data_all all
;
3869 gimple_seq stmts
= NULL
;
3873 assign_parms_initialize_all (&all
);
3874 fnargs
= assign_parms_augmented_arg_list (&all
);
3876 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3878 struct assign_parm_data_one data
;
3880 /* Extract the type of PARM; adjust it according to ABI. */
3881 assign_parm_find_data_types (&all
, parm
, &data
);
3883 /* Early out for errors and void parameters. */
3884 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3887 /* Update info on where next arg arrives in registers. */
3888 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.arg
);
3890 /* ??? Once upon a time variable_size stuffed parameter list
3891 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3892 turned out to be less than manageable in the gimple world.
3893 Now we have to hunt them down ourselves. */
3894 walk_tree_without_duplicates (&data
.arg
.type
,
3895 gimplify_parm_type
, &stmts
);
3897 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3899 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3900 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3903 if (data
.arg
.pass_by_reference
)
3905 tree type
= TREE_TYPE (data
.arg
.type
);
3906 function_arg_info
orig_arg (type
, data
.arg
.named
);
3907 if (reference_callee_copied (&all
.args_so_far_v
, orig_arg
))
3911 /* For constant-sized objects, this is trivial; for
3912 variable-sized objects, we have to play games. */
3913 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3914 && !(flag_stack_check
== GENERIC_STACK_CHECK
3915 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3916 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3918 local
= create_tmp_var (type
, get_name (parm
));
3919 DECL_IGNORED_P (local
) = 0;
3920 /* If PARM was addressable, move that flag over
3921 to the local copy, as its address will be taken,
3922 not the PARMs. Keep the parms address taken
3923 as we'll query that flag during gimplification. */
3924 if (TREE_ADDRESSABLE (parm
))
3925 TREE_ADDRESSABLE (local
) = 1;
3926 if (DECL_NOT_GIMPLE_REG_P (parm
))
3927 DECL_NOT_GIMPLE_REG_P (local
) = 1;
3929 if (!is_gimple_reg (local
)
3930 && flag_stack_reuse
!= SR_NONE
)
3932 tree clobber
= build_clobber (type
);
3933 gimple
*clobber_stmt
;
3934 clobber_stmt
= gimple_build_assign (local
, clobber
);
3935 gimple_seq_add_stmt (cleanup
, clobber_stmt
);
3940 tree ptr_type
, addr
;
3942 ptr_type
= build_pointer_type (type
);
3943 addr
= create_tmp_reg (ptr_type
, get_name (parm
));
3944 DECL_IGNORED_P (addr
) = 0;
3945 local
= build_fold_indirect_ref (addr
);
3947 t
= build_alloca_call_expr (DECL_SIZE_UNIT (parm
),
3949 max_int_size_in_bytes (type
));
3950 /* The call has been built for a variable-sized object. */
3951 CALL_ALLOCA_FOR_VAR_P (t
) = 1;
3952 t
= fold_convert (ptr_type
, t
);
3953 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3954 gimplify_and_add (t
, &stmts
);
3957 gimplify_assign (local
, parm
, &stmts
);
3959 SET_DECL_VALUE_EXPR (parm
, local
);
3960 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3970 /* Compute the size and offset from the start of the stacked arguments for a
3971 parm passed in mode PASSED_MODE and with type TYPE.
3973 INITIAL_OFFSET_PTR points to the current offset into the stacked
3976 The starting offset and size for this parm are returned in
3977 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3978 nonzero, the offset is that of stack slot, which is returned in
3979 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3980 padding required from the initial offset ptr to the stack slot.
3982 IN_REGS is nonzero if the argument will be passed in registers. It will
3983 never be set if REG_PARM_STACK_SPACE is not defined.
3985 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3986 for arguments which are passed in registers.
3988 FNDECL is the function in which the argument was defined.
3990 There are two types of rounding that are done. The first, controlled by
3991 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3992 argument list to be aligned to the specific boundary (in bits). This
3993 rounding affects the initial and starting offsets, but not the argument
3996 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3997 optionally rounds the size of the parm to PARM_BOUNDARY. The
3998 initial offset is not affected by this rounding, while the size always
3999 is and the starting offset may be. */
4001 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
4002 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
4003 callers pass in the total size of args so far as
4004 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
4007 locate_and_pad_parm (machine_mode passed_mode
, tree type
, int in_regs
,
4008 int reg_parm_stack_space
, int partial
,
4009 tree fndecl ATTRIBUTE_UNUSED
,
4010 struct args_size
*initial_offset_ptr
,
4011 struct locate_and_pad_arg_data
*locate
)
4014 pad_direction where_pad
;
4015 unsigned int boundary
, round_boundary
;
4016 int part_size_in_regs
;
4018 /* If we have found a stack parm before we reach the end of the
4019 area reserved for registers, skip that area. */
4022 if (reg_parm_stack_space
> 0)
4024 if (initial_offset_ptr
->var
4025 || !ordered_p (initial_offset_ptr
->constant
,
4026 reg_parm_stack_space
))
4028 initial_offset_ptr
->var
4029 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
4030 ssize_int (reg_parm_stack_space
));
4031 initial_offset_ptr
->constant
= 0;
4034 initial_offset_ptr
->constant
4035 = ordered_max (initial_offset_ptr
->constant
,
4036 reg_parm_stack_space
);
4040 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
4043 ? arg_size_in_bytes (type
)
4044 : size_int (GET_MODE_SIZE (passed_mode
)));
4045 where_pad
= targetm
.calls
.function_arg_padding (passed_mode
, type
);
4046 boundary
= targetm
.calls
.function_arg_boundary (passed_mode
, type
);
4047 round_boundary
= targetm
.calls
.function_arg_round_boundary (passed_mode
,
4049 locate
->where_pad
= where_pad
;
4051 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4052 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
4053 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
4055 locate
->boundary
= boundary
;
4057 if (SUPPORTS_STACK_ALIGNMENT
)
4059 /* stack_alignment_estimated can't change after stack has been
4061 if (crtl
->stack_alignment_estimated
< boundary
)
4063 if (!crtl
->stack_realign_processed
)
4064 crtl
->stack_alignment_estimated
= boundary
;
4067 /* If stack is realigned and stack alignment value
4068 hasn't been finalized, it is OK not to increase
4069 stack_alignment_estimated. The bigger alignment
4070 requirement is recorded in stack_alignment_needed
4072 gcc_assert (!crtl
->stack_realign_finalized
4073 && crtl
->stack_realign_needed
);
4078 if (ARGS_GROW_DOWNWARD
)
4080 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
4081 if (initial_offset_ptr
->var
)
4082 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
4083 initial_offset_ptr
->var
);
4087 if (where_pad
!= PAD_NONE
4088 && (!tree_fits_uhwi_p (sizetree
)
4089 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
4090 s2
= round_up (s2
, round_boundary
/ BITS_PER_UNIT
);
4091 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
4094 locate
->slot_offset
.constant
+= part_size_in_regs
;
4096 if (!in_regs
|| reg_parm_stack_space
> 0)
4097 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
4098 &locate
->alignment_pad
);
4100 locate
->size
.constant
= (-initial_offset_ptr
->constant
4101 - locate
->slot_offset
.constant
);
4102 if (initial_offset_ptr
->var
)
4103 locate
->size
.var
= size_binop (MINUS_EXPR
,
4104 size_binop (MINUS_EXPR
,
4106 initial_offset_ptr
->var
),
4107 locate
->slot_offset
.var
);
4109 /* Pad_below needs the pre-rounded size to know how much to pad
4111 locate
->offset
= locate
->slot_offset
;
4112 if (where_pad
== PAD_DOWNWARD
)
4113 pad_below (&locate
->offset
, passed_mode
, sizetree
);
4118 if (!in_regs
|| reg_parm_stack_space
> 0)
4119 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
4120 &locate
->alignment_pad
);
4121 locate
->slot_offset
= *initial_offset_ptr
;
4123 #ifdef PUSH_ROUNDING
4124 if (passed_mode
!= BLKmode
)
4125 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
4128 /* Pad_below needs the pre-rounded size to know how much to pad below
4129 so this must be done before rounding up. */
4130 locate
->offset
= locate
->slot_offset
;
4131 if (where_pad
== PAD_DOWNWARD
)
4132 pad_below (&locate
->offset
, passed_mode
, sizetree
);
4134 if (where_pad
!= PAD_NONE
4135 && (!tree_fits_uhwi_p (sizetree
)
4136 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
4137 sizetree
= round_up (sizetree
, round_boundary
/ BITS_PER_UNIT
);
4139 ADD_PARM_SIZE (locate
->size
, sizetree
);
4141 locate
->size
.constant
-= part_size_in_regs
;
4144 locate
->offset
.constant
4145 += targetm
.calls
.function_arg_offset (passed_mode
, type
);
4148 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4149 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4152 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
4153 struct args_size
*alignment_pad
)
4155 tree save_var
= NULL_TREE
;
4156 poly_int64 save_constant
= 0;
4157 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
4158 poly_int64 sp_offset
= STACK_POINTER_OFFSET
;
4160 #ifdef SPARC_STACK_BOUNDARY_HACK
4161 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4162 the real alignment of %sp. However, when it does this, the
4163 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4164 if (SPARC_STACK_BOUNDARY_HACK
)
4168 if (boundary
> PARM_BOUNDARY
)
4170 save_var
= offset_ptr
->var
;
4171 save_constant
= offset_ptr
->constant
;
4174 alignment_pad
->var
= NULL_TREE
;
4175 alignment_pad
->constant
= 0;
4177 if (boundary
> BITS_PER_UNIT
)
4181 || !known_misalignment (offset_ptr
->constant
+ sp_offset
,
4182 boundary_in_bytes
, &misalign
))
4184 tree sp_offset_tree
= ssize_int (sp_offset
);
4185 tree offset
= size_binop (PLUS_EXPR
,
4186 ARGS_SIZE_TREE (*offset_ptr
),
4189 if (ARGS_GROW_DOWNWARD
)
4190 rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
4192 rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
4194 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
4195 /* ARGS_SIZE_TREE includes constant term. */
4196 offset_ptr
->constant
= 0;
4197 if (boundary
> PARM_BOUNDARY
)
4198 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
4203 if (ARGS_GROW_DOWNWARD
)
4204 offset_ptr
->constant
-= misalign
;
4206 offset_ptr
->constant
+= -misalign
& (boundary_in_bytes
- 1);
4208 if (boundary
> PARM_BOUNDARY
)
4209 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
4215 pad_below (struct args_size
*offset_ptr
, machine_mode passed_mode
, tree sizetree
)
4217 unsigned int align
= PARM_BOUNDARY
/ BITS_PER_UNIT
;
4219 if (passed_mode
!= BLKmode
4220 && known_misalignment (GET_MODE_SIZE (passed_mode
), align
, &misalign
))
4221 offset_ptr
->constant
+= -misalign
& (align
- 1);
4224 if (TREE_CODE (sizetree
) != INTEGER_CST
4225 || (TREE_INT_CST_LOW (sizetree
) & (align
- 1)) != 0)
4227 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4228 tree s2
= round_up (sizetree
, align
);
4230 ADD_PARM_SIZE (*offset_ptr
, s2
);
4231 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4237 /* True if register REGNO was alive at a place where `setjmp' was
4238 called and was set more than once or is an argument. Such regs may
4239 be clobbered by `longjmp'. */
4242 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
4244 /* There appear to be cases where some local vars never reach the
4245 backend but have bogus regnos. */
4246 if (regno
>= max_reg_num ())
4249 return ((REG_N_SETS (regno
) > 1
4250 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun
)),
4252 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
4255 /* Walk the tree of blocks describing the binding levels within a
4256 function and warn about variables the might be killed by setjmp or
4257 vfork. This is done after calling flow_analysis before register
4258 allocation since that will clobber the pseudo-regs to hard
4262 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
4266 for (decl
= BLOCK_VARS (block
); decl
; decl
= DECL_CHAIN (decl
))
4269 && DECL_RTL_SET_P (decl
)
4270 && REG_P (DECL_RTL (decl
))
4271 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4272 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
4273 " %<longjmp%> or %<vfork%>", decl
);
4276 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
4277 setjmp_vars_warning (setjmp_crosses
, sub
);
4280 /* Do the appropriate part of setjmp_vars_warning
4281 but for arguments instead of local variables. */
4284 setjmp_args_warning (bitmap setjmp_crosses
)
4287 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4288 decl
; decl
= DECL_CHAIN (decl
))
4289 if (DECL_RTL (decl
) != 0
4290 && REG_P (DECL_RTL (decl
))
4291 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4292 warning (OPT_Wclobbered
,
4293 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4297 /* Generate warning messages for variables live across setjmp. */
4300 generate_setjmp_warnings (void)
4302 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
4304 if (n_basic_blocks_for_fn (cfun
) == NUM_FIXED_BLOCKS
4305 || bitmap_empty_p (setjmp_crosses
))
4308 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
4309 setjmp_args_warning (setjmp_crosses
);
4313 /* Reverse the order of elements in the fragment chain T of blocks,
4314 and return the new head of the chain (old last element).
4315 In addition to that clear BLOCK_SAME_RANGE flags when needed
4316 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4317 its super fragment origin. */
4320 block_fragments_nreverse (tree t
)
4322 tree prev
= 0, block
, next
, prev_super
= 0;
4323 tree super
= BLOCK_SUPERCONTEXT (t
);
4324 if (BLOCK_FRAGMENT_ORIGIN (super
))
4325 super
= BLOCK_FRAGMENT_ORIGIN (super
);
4326 for (block
= t
; block
; block
= next
)
4328 next
= BLOCK_FRAGMENT_CHAIN (block
);
4329 BLOCK_FRAGMENT_CHAIN (block
) = prev
;
4330 if ((prev
&& !BLOCK_SAME_RANGE (prev
))
4331 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block
))
4333 BLOCK_SAME_RANGE (block
) = 0;
4334 prev_super
= BLOCK_SUPERCONTEXT (block
);
4335 BLOCK_SUPERCONTEXT (block
) = super
;
4338 t
= BLOCK_FRAGMENT_ORIGIN (t
);
4339 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t
))
4341 BLOCK_SAME_RANGE (t
) = 0;
4342 BLOCK_SUPERCONTEXT (t
) = super
;
4346 /* Reverse the order of elements in the chain T of blocks,
4347 and return the new head of the chain (old last element).
4348 Also do the same on subblocks and reverse the order of elements
4349 in BLOCK_FRAGMENT_CHAIN as well. */
4352 blocks_nreverse_all (tree t
)
4354 tree prev
= 0, block
, next
;
4355 for (block
= t
; block
; block
= next
)
4357 next
= BLOCK_CHAIN (block
);
4358 BLOCK_CHAIN (block
) = prev
;
4359 if (BLOCK_FRAGMENT_CHAIN (block
)
4360 && BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
)
4362 BLOCK_FRAGMENT_CHAIN (block
)
4363 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block
));
4364 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block
)))
4365 BLOCK_SAME_RANGE (block
) = 0;
4367 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4374 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4375 and create duplicate blocks. */
4376 /* ??? Need an option to either create block fragments or to create
4377 abstract origin duplicates of a source block. It really depends
4378 on what optimization has been performed. */
4381 reorder_blocks (void)
4383 tree block
= DECL_INITIAL (current_function_decl
);
4385 if (block
== NULL_TREE
)
4388 auto_vec
<tree
, 10> block_stack
;
4390 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4391 clear_block_marks (block
);
4393 /* Prune the old trees away, so that they don't get in the way. */
4394 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
4395 BLOCK_CHAIN (block
) = NULL_TREE
;
4397 /* Recreate the block tree from the note nesting. */
4398 reorder_blocks_1 (get_insns (), block
, &block_stack
);
4399 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4402 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4405 clear_block_marks (tree block
)
4409 TREE_ASM_WRITTEN (block
) = 0;
4410 clear_block_marks (BLOCK_SUBBLOCKS (block
));
4411 block
= BLOCK_CHAIN (block
);
4416 reorder_blocks_1 (rtx_insn
*insns
, tree current_block
,
4417 vec
<tree
> *p_block_stack
)
4420 tree prev_beg
= NULL_TREE
, prev_end
= NULL_TREE
;
4422 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
4426 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
4428 tree block
= NOTE_BLOCK (insn
);
4431 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
);
4435 BLOCK_SAME_RANGE (prev_end
) = 0;
4436 prev_end
= NULL_TREE
;
4438 /* If we have seen this block before, that means it now
4439 spans multiple address regions. Create a new fragment. */
4440 if (TREE_ASM_WRITTEN (block
))
4442 tree new_block
= copy_node (block
);
4444 BLOCK_SAME_RANGE (new_block
) = 0;
4445 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
4446 BLOCK_FRAGMENT_CHAIN (new_block
)
4447 = BLOCK_FRAGMENT_CHAIN (origin
);
4448 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
4450 NOTE_BLOCK (insn
) = new_block
;
4454 if (prev_beg
== current_block
&& prev_beg
)
4455 BLOCK_SAME_RANGE (block
) = 1;
4459 BLOCK_SUBBLOCKS (block
) = 0;
4460 TREE_ASM_WRITTEN (block
) = 1;
4461 /* When there's only one block for the entire function,
4462 current_block == block and we mustn't do this, it
4463 will cause infinite recursion. */
4464 if (block
!= current_block
)
4467 if (block
!= origin
)
4468 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
4469 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4472 if (p_block_stack
->is_empty ())
4473 super
= current_block
;
4476 super
= p_block_stack
->last ();
4477 gcc_assert (super
== current_block
4478 || BLOCK_FRAGMENT_ORIGIN (super
)
4481 BLOCK_SUPERCONTEXT (block
) = super
;
4482 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
4483 BLOCK_SUBBLOCKS (current_block
) = block
;
4484 current_block
= origin
;
4486 p_block_stack
->safe_push (block
);
4488 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
4490 NOTE_BLOCK (insn
) = p_block_stack
->pop ();
4491 current_block
= BLOCK_SUPERCONTEXT (current_block
);
4492 if (BLOCK_FRAGMENT_ORIGIN (current_block
))
4493 current_block
= BLOCK_FRAGMENT_ORIGIN (current_block
);
4494 prev_beg
= NULL_TREE
;
4495 prev_end
= BLOCK_SAME_RANGE (NOTE_BLOCK (insn
))
4496 ? NOTE_BLOCK (insn
) : NULL_TREE
;
4501 prev_beg
= NULL_TREE
;
4503 BLOCK_SAME_RANGE (prev_end
) = 0;
4504 prev_end
= NULL_TREE
;
4509 /* Reverse the order of elements in the chain T of blocks,
4510 and return the new head of the chain (old last element). */
4513 blocks_nreverse (tree t
)
4515 tree prev
= 0, block
, next
;
4516 for (block
= t
; block
; block
= next
)
4518 next
= BLOCK_CHAIN (block
);
4519 BLOCK_CHAIN (block
) = prev
;
4525 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4526 by modifying the last node in chain 1 to point to chain 2. */
4529 block_chainon (tree op1
, tree op2
)
4538 for (t1
= op1
; BLOCK_CHAIN (t1
); t1
= BLOCK_CHAIN (t1
))
4540 BLOCK_CHAIN (t1
) = op2
;
4542 #ifdef ENABLE_TREE_CHECKING
4545 for (t2
= op2
; t2
; t2
= BLOCK_CHAIN (t2
))
4546 gcc_assert (t2
!= t1
);
4553 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4554 non-NULL, list them all into VECTOR, in a depth-first preorder
4555 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4559 all_blocks (tree block
, tree
*vector
)
4565 TREE_ASM_WRITTEN (block
) = 0;
4567 /* Record this block. */
4569 vector
[n_blocks
] = block
;
4573 /* Record the subblocks, and their subblocks... */
4574 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
4575 vector
? vector
+ n_blocks
: 0);
4576 block
= BLOCK_CHAIN (block
);
4582 /* Return a vector containing all the blocks rooted at BLOCK. The
4583 number of elements in the vector is stored in N_BLOCKS_P. The
4584 vector is dynamically allocated; it is the caller's responsibility
4585 to call `free' on the pointer returned. */
4588 get_block_vector (tree block
, int *n_blocks_p
)
4592 *n_blocks_p
= all_blocks (block
, NULL
);
4593 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
4594 all_blocks (block
, block_vector
);
4596 return block_vector
;
4599 static GTY(()) int next_block_index
= 2;
4601 /* Set BLOCK_NUMBER for all the blocks in FN. */
4604 number_blocks (tree fn
)
4610 /* For XCOFF debugging output, we start numbering the blocks
4611 from 1 within each function, rather than keeping a running
4613 #if defined (XCOFF_DEBUGGING_INFO)
4614 if (write_symbols
== XCOFF_DEBUG
)
4615 next_block_index
= 1;
4618 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
4620 /* The top-level BLOCK isn't numbered at all. */
4621 for (i
= 1; i
< n_blocks
; ++i
)
4622 /* We number the blocks from two. */
4623 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
4625 free (block_vector
);
4630 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4633 debug_find_var_in_block_tree (tree var
, tree block
)
4637 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4641 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4643 tree ret
= debug_find_var_in_block_tree (var
, t
);
4651 /* Keep track of whether we're in a dummy function context. If we are,
4652 we don't want to invoke the set_current_function hook, because we'll
4653 get into trouble if the hook calls target_reinit () recursively or
4654 when the initial initialization is not yet complete. */
4656 static bool in_dummy_function
;
4658 /* Invoke the target hook when setting cfun. Update the optimization options
4659 if the function uses different options than the default. */
4662 invoke_set_current_function_hook (tree fndecl
)
4664 if (!in_dummy_function
)
4666 tree opts
= ((fndecl
)
4667 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4668 : optimization_default_node
);
4671 opts
= optimization_default_node
;
4673 /* Change optimization options if needed. */
4674 if (optimization_current_node
!= opts
)
4676 optimization_current_node
= opts
;
4677 cl_optimization_restore (&global_options
, &global_options_set
,
4678 TREE_OPTIMIZATION (opts
));
4681 targetm
.set_current_function (fndecl
);
4682 this_fn_optabs
= this_target_optabs
;
4684 /* Initialize global alignment variables after op. */
4685 parse_alignment_opts ();
4687 if (opts
!= optimization_default_node
)
4689 init_tree_optimization_optabs (opts
);
4690 if (TREE_OPTIMIZATION_OPTABS (opts
))
4691 this_fn_optabs
= (struct target_optabs
*)
4692 TREE_OPTIMIZATION_OPTABS (opts
);
4697 /* cfun should never be set directly; use this function. */
4700 set_cfun (struct function
*new_cfun
, bool force
)
4702 if (cfun
!= new_cfun
|| force
)
4705 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4706 redirect_edge_var_map_empty ();
4710 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4712 static vec
<function
*> cfun_stack
;
4714 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4715 current_function_decl accordingly. */
4718 push_cfun (struct function
*new_cfun
)
4720 gcc_assert ((!cfun
&& !current_function_decl
)
4721 || (cfun
&& current_function_decl
== cfun
->decl
));
4722 cfun_stack
.safe_push (cfun
);
4723 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4724 set_cfun (new_cfun
);
4727 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4732 struct function
*new_cfun
= cfun_stack
.pop ();
4733 /* When in_dummy_function, we do have a cfun but current_function_decl is
4734 NULL. We also allow pushing NULL cfun and subsequently changing
4735 current_function_decl to something else and have both restored by
4737 gcc_checking_assert (in_dummy_function
4739 || current_function_decl
== cfun
->decl
);
4740 set_cfun (new_cfun
);
4741 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4744 /* Return value of funcdef and increase it. */
4746 get_next_funcdef_no (void)
4748 return funcdef_no
++;
4751 /* Return value of funcdef. */
4753 get_last_funcdef_no (void)
4758 /* Allocate and initialize the stack usage info data structure for the
4759 current function. */
4761 allocate_stack_usage_info (void)
4763 gcc_assert (!cfun
->su
);
4764 cfun
->su
= ggc_cleared_alloc
<stack_usage
> ();
4765 cfun
->su
->static_stack_size
= -1;
4768 /* Allocate a function structure for FNDECL and set its contents
4769 to the defaults. Set cfun to the newly-allocated object.
4770 Some of the helper functions invoked during initialization assume
4771 that cfun has already been set. Therefore, assign the new object
4772 directly into cfun and invoke the back end hook explicitly at the
4773 very end, rather than initializing a temporary and calling set_cfun
4776 ABSTRACT_P is true if this is a function that will never be seen by
4777 the middle-end. Such functions are front-end concepts (like C++
4778 function templates) that do not correspond directly to functions
4779 placed in object files. */
4782 allocate_struct_function (tree fndecl
, bool abstract_p
)
4784 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4786 cfun
= ggc_cleared_alloc
<function
> ();
4788 init_eh_for_function ();
4790 if (init_machine_status
)
4791 cfun
->machine
= (*init_machine_status
) ();
4793 #ifdef OVERRIDE_ABI_FORMAT
4794 OVERRIDE_ABI_FORMAT (fndecl
);
4797 if (fndecl
!= NULL_TREE
)
4799 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4800 cfun
->decl
= fndecl
;
4801 current_function_funcdef_no
= get_next_funcdef_no ();
4804 invoke_set_current_function_hook (fndecl
);
4806 if (fndecl
!= NULL_TREE
)
4808 tree result
= DECL_RESULT (fndecl
);
4812 /* Now that we have activated any function-specific attributes
4813 that might affect layout, particularly vector modes, relayout
4814 each of the parameters and the result. */
4815 relayout_decl (result
);
4816 for (tree parm
= DECL_ARGUMENTS (fndecl
); parm
;
4817 parm
= DECL_CHAIN (parm
))
4818 relayout_decl (parm
);
4820 /* Similarly relayout the function decl. */
4821 targetm
.target_option
.relayout_function (fndecl
);
4824 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4826 #ifdef PCC_STATIC_STRUCT_RETURN
4827 cfun
->returns_pcc_struct
= 1;
4829 cfun
->returns_struct
= 1;
4832 cfun
->stdarg
= stdarg_p (fntype
);
4834 /* Assume all registers in stdarg functions need to be saved. */
4835 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4836 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4838 /* ??? This could be set on a per-function basis by the front-end
4839 but is this worth the hassle? */
4840 cfun
->can_throw_non_call_exceptions
= flag_non_call_exceptions
;
4841 cfun
->can_delete_dead_exceptions
= flag_delete_dead_exceptions
;
4843 if (!profile_flag
&& !flag_instrument_function_entry_exit
)
4844 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl
) = 1;
4846 if (flag_callgraph_info
)
4847 allocate_stack_usage_info ();
4850 /* Don't enable begin stmt markers if var-tracking at assignments is
4851 disabled. The markers make little sense without the variable
4852 binding annotations among them. */
4853 cfun
->debug_nonbind_markers
= lang_hooks
.emits_begin_stmt
4854 && MAY_HAVE_DEBUG_MARKER_STMTS
;
4857 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4858 instead of just setting it. */
4861 push_struct_function (tree fndecl
)
4863 /* When in_dummy_function we might be in the middle of a pop_cfun and
4864 current_function_decl and cfun may not match. */
4865 gcc_assert (in_dummy_function
4866 || (!cfun
&& !current_function_decl
)
4867 || (cfun
&& current_function_decl
== cfun
->decl
));
4868 cfun_stack
.safe_push (cfun
);
4869 current_function_decl
= fndecl
;
4870 allocate_struct_function (fndecl
, false);
4873 /* Reset crtl and other non-struct-function variables to defaults as
4874 appropriate for emitting rtl at the start of a function. */
4877 prepare_function_start (void)
4879 gcc_assert (!get_last_insn ());
4881 if (in_dummy_function
)
4882 crtl
->abi
= &default_function_abi
;
4884 crtl
->abi
= &fndecl_abi (cfun
->decl
).base_abi ();
4888 init_varasm_status ();
4890 default_rtl_profile ();
4892 if (flag_stack_usage_info
&& !flag_callgraph_info
)
4893 allocate_stack_usage_info ();
4895 cse_not_expected
= ! optimize
;
4897 /* Caller save not needed yet. */
4898 caller_save_needed
= 0;
4900 /* We haven't done register allocation yet. */
4903 /* Indicate that we have not instantiated virtual registers yet. */
4904 virtuals_instantiated
= 0;
4906 /* Indicate that we want CONCATs now. */
4907 generating_concat_p
= 1;
4909 /* Indicate we have no need of a frame pointer yet. */
4910 frame_pointer_needed
= 0;
4914 push_dummy_function (bool with_decl
)
4916 tree fn_decl
, fn_type
, fn_result_decl
;
4918 gcc_assert (!in_dummy_function
);
4919 in_dummy_function
= true;
4923 fn_type
= build_function_type_list (void_type_node
, NULL_TREE
);
4924 fn_decl
= build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
, NULL_TREE
,
4926 fn_result_decl
= build_decl (UNKNOWN_LOCATION
, RESULT_DECL
,
4927 NULL_TREE
, void_type_node
);
4928 DECL_RESULT (fn_decl
) = fn_result_decl
;
4931 fn_decl
= NULL_TREE
;
4933 push_struct_function (fn_decl
);
4936 /* Initialize the rtl expansion mechanism so that we can do simple things
4937 like generate sequences. This is used to provide a context during global
4938 initialization of some passes. You must call expand_dummy_function_end
4939 to exit this context. */
4942 init_dummy_function_start (void)
4944 push_dummy_function (false);
4945 prepare_function_start ();
4948 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4949 and initialize static variables for generating RTL for the statements
4953 init_function_start (tree subr
)
4955 /* Initialize backend, if needed. */
4958 prepare_function_start ();
4959 decide_function_section (subr
);
4961 /* Warn if this value is an aggregate type,
4962 regardless of which calling convention we are using for it. */
4963 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4964 warning (OPT_Waggregate_return
, "function returns an aggregate");
4967 /* Expand code to verify the stack_protect_guard. This is invoked at
4968 the end of a function to be protected. */
4971 stack_protect_epilogue (void)
4973 tree guard_decl
= crtl
->stack_protect_guard_decl
;
4974 rtx_code_label
*label
= gen_label_rtx ();
4976 rtx_insn
*seq
= NULL
;
4978 x
= expand_normal (crtl
->stack_protect_guard
);
4980 if (targetm
.have_stack_protect_combined_test () && guard_decl
)
4982 gcc_assert (DECL_P (guard_decl
));
4983 y
= DECL_RTL (guard_decl
);
4984 /* Allow the target to compute address of Y and compare it with X without
4985 leaking Y into a register. This combined address + compare pattern
4986 allows the target to prevent spilling of any intermediate results by
4987 splitting it after register allocator. */
4988 seq
= targetm
.gen_stack_protect_combined_test (x
, y
, label
);
4993 y
= expand_normal (guard_decl
);
4997 /* Allow the target to compare Y with X without leaking either into
4999 if (targetm
.have_stack_protect_test ())
5000 seq
= targetm
.gen_stack_protect_test (x
, y
, label
);
5006 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
5008 /* The noreturn predictor has been moved to the tree level. The rtl-level
5009 predictors estimate this branch about 20%, which isn't enough to get
5010 things moved out of line. Since this is the only extant case of adding
5011 a noreturn function at the rtl level, it doesn't seem worth doing ought
5012 except adding the prediction by hand. */
5013 rtx_insn
*tmp
= get_last_insn ();
5015 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
5017 expand_call (targetm
.stack_protect_fail (), NULL_RTX
, /*ignore=*/true);
5022 /* Start the RTL for a new function, and set variables used for
5024 SUBR is the FUNCTION_DECL node.
5025 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5026 the function's parameters, which must be run at any return statement. */
5029 expand_function_start (tree subr
)
5031 /* Make sure volatile mem refs aren't considered
5032 valid operands of arithmetic insns. */
5033 init_recog_no_volatile ();
5037 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
5040 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
5042 /* Make the label for return statements to jump to. Do not special
5043 case machines with special return instructions -- they will be
5044 handled later during jump, ifcvt, or epilogue creation. */
5045 return_label
= gen_label_rtx ();
5047 /* Initialize rtx used to return the value. */
5048 /* Do this before assign_parms so that we copy the struct value address
5049 before any library calls that assign parms might generate. */
5051 /* Decide whether to return the value in memory or in a register. */
5052 tree res
= DECL_RESULT (subr
);
5053 if (aggregate_value_p (res
, subr
))
5055 /* Returning something that won't go in a register. */
5056 rtx value_address
= 0;
5058 #ifdef PCC_STATIC_STRUCT_RETURN
5059 if (cfun
->returns_pcc_struct
)
5061 int size
= int_size_in_bytes (TREE_TYPE (res
));
5062 value_address
= assemble_static_space (size
);
5067 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
5068 /* Expect to be passed the address of a place to store the value.
5069 If it is passed as an argument, assign_parms will take care of
5073 value_address
= gen_reg_rtx (Pmode
);
5074 emit_move_insn (value_address
, sv
);
5079 rtx x
= value_address
;
5080 if (!DECL_BY_REFERENCE (res
))
5082 x
= gen_rtx_MEM (DECL_MODE (res
), x
);
5083 set_mem_attributes (x
, res
, 1);
5085 set_parm_rtl (res
, x
);
5088 else if (DECL_MODE (res
) == VOIDmode
)
5089 /* If return mode is void, this decl rtl should not be used. */
5090 set_parm_rtl (res
, NULL_RTX
);
5093 /* Compute the return values into a pseudo reg, which we will copy
5094 into the true return register after the cleanups are done. */
5095 tree return_type
= TREE_TYPE (res
);
5097 /* If we may coalesce this result, make sure it has the expected mode
5098 in case it was promoted. But we need not bother about BLKmode. */
5099 machine_mode promoted_mode
5100 = flag_tree_coalesce_vars
&& is_gimple_reg (res
)
5101 ? promote_ssa_mode (ssa_default_def (cfun
, res
), NULL
)
5104 if (promoted_mode
!= BLKmode
)
5105 set_parm_rtl (res
, gen_reg_rtx (promoted_mode
));
5106 else if (TYPE_MODE (return_type
) != BLKmode
5107 && targetm
.calls
.return_in_msb (return_type
))
5108 /* expand_function_end will insert the appropriate padding in
5109 this case. Use the return value's natural (unpadded) mode
5110 within the function proper. */
5111 set_parm_rtl (res
, gen_reg_rtx (TYPE_MODE (return_type
)));
5114 /* In order to figure out what mode to use for the pseudo, we
5115 figure out what the mode of the eventual return register will
5116 actually be, and use that. */
5117 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
5119 /* Structures that are returned in registers are not
5120 aggregate_value_p, so we may see a PARALLEL or a REG. */
5121 if (REG_P (hard_reg
))
5122 set_parm_rtl (res
, gen_reg_rtx (GET_MODE (hard_reg
)));
5125 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
5126 set_parm_rtl (res
, gen_group_rtx (hard_reg
));
5130 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5131 result to the real return register(s). */
5132 DECL_REGISTER (res
) = 1;
5135 /* Initialize rtx for parameters and local variables.
5136 In some cases this requires emitting insns. */
5137 assign_parms (subr
);
5139 /* If function gets a static chain arg, store it. */
5140 if (cfun
->static_chain_decl
)
5142 tree parm
= cfun
->static_chain_decl
;
5147 local
= gen_reg_rtx (promote_decl_mode (parm
, &unsignedp
));
5148 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
5150 set_decl_incoming_rtl (parm
, chain
, false);
5151 set_parm_rtl (parm
, local
);
5152 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
5154 if (GET_MODE (local
) != GET_MODE (chain
))
5156 convert_move (local
, chain
, unsignedp
);
5157 insn
= get_last_insn ();
5160 insn
= emit_move_insn (local
, chain
);
5162 /* Mark the register as eliminable, similar to parameters. */
5164 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
5165 set_dst_reg_note (insn
, REG_EQUIV
, chain
, local
);
5167 /* If we aren't optimizing, save the static chain onto the stack. */
5170 tree saved_static_chain_decl
5171 = build_decl (DECL_SOURCE_LOCATION (parm
), VAR_DECL
,
5172 DECL_NAME (parm
), TREE_TYPE (parm
));
5173 rtx saved_static_chain_rtx
5174 = assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5175 SET_DECL_RTL (saved_static_chain_decl
, saved_static_chain_rtx
);
5176 emit_move_insn (saved_static_chain_rtx
, chain
);
5177 SET_DECL_VALUE_EXPR (parm
, saved_static_chain_decl
);
5178 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
5182 /* The following was moved from init_function_start.
5183 The move was supposed to make sdb output more accurate. */
5184 /* Indicate the beginning of the function body,
5185 as opposed to parm setup. */
5186 emit_note (NOTE_INSN_FUNCTION_BEG
);
5188 gcc_assert (NOTE_P (get_last_insn ()));
5190 parm_birth_insn
= get_last_insn ();
5192 /* If the function receives a non-local goto, then store the
5193 bits we need to restore the frame pointer. */
5194 if (cfun
->nonlocal_goto_save_area
)
5199 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
5200 gcc_assert (DECL_RTL_SET_P (var
));
5202 t_save
= build4 (ARRAY_REF
,
5203 TREE_TYPE (TREE_TYPE (cfun
->nonlocal_goto_save_area
)),
5204 cfun
->nonlocal_goto_save_area
,
5205 integer_zero_node
, NULL_TREE
, NULL_TREE
);
5206 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
5207 gcc_assert (GET_MODE (r_save
) == Pmode
);
5209 emit_move_insn (r_save
, hard_frame_pointer_rtx
);
5210 update_nonlocal_goto_save_area ();
5216 PROFILE_HOOK (current_function_funcdef_no
);
5220 /* If we are doing generic stack checking, the probe should go here. */
5221 if (flag_stack_check
== GENERIC_STACK_CHECK
)
5222 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
5226 pop_dummy_function (void)
5229 in_dummy_function
= false;
5232 /* Undo the effects of init_dummy_function_start. */
5234 expand_dummy_function_end (void)
5236 gcc_assert (in_dummy_function
);
5238 /* End any sequences that failed to be closed due to syntax errors. */
5239 while (in_sequence_p ())
5242 /* Outside function body, can't compute type's actual size
5243 until next function's body starts. */
5245 free_after_parsing (cfun
);
5246 free_after_compilation (cfun
);
5247 pop_dummy_function ();
5250 /* Helper for diddle_return_value. */
5253 diddle_return_value_1 (void (*doit
) (rtx
, void *), void *arg
, rtx outgoing
)
5258 if (REG_P (outgoing
))
5259 (*doit
) (outgoing
, arg
);
5260 else if (GET_CODE (outgoing
) == PARALLEL
)
5264 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
5266 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
5268 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
5274 /* Call DOIT for each hard register used as a return value from
5275 the current function. */
5278 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
5280 diddle_return_value_1 (doit
, arg
, crtl
->return_rtx
);
5284 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
5290 clobber_return_register (void)
5292 diddle_return_value (do_clobber_return_reg
, NULL
);
5294 /* In case we do use pseudo to return value, clobber it too. */
5295 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5297 tree decl_result
= DECL_RESULT (current_function_decl
);
5298 rtx decl_rtl
= DECL_RTL (decl_result
);
5299 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
5301 do_clobber_return_reg (decl_rtl
, NULL
);
5307 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
5313 use_return_register (void)
5315 diddle_return_value (do_use_return_reg
, NULL
);
5318 /* Generate RTL for the end of the current function. */
5321 expand_function_end (void)
5323 /* If arg_pointer_save_area was referenced only from a nested
5324 function, we will not have initialized it yet. Do that now. */
5325 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
5326 get_arg_pointer_save_area ();
5328 /* If we are doing generic stack checking and this function makes calls,
5329 do a stack probe at the start of the function to ensure we have enough
5330 space for another stack frame. */
5331 if (flag_stack_check
== GENERIC_STACK_CHECK
)
5333 rtx_insn
*insn
, *seq
;
5335 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5338 rtx max_frame_size
= GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
);
5340 if (STACK_CHECK_MOVING_SP
)
5341 anti_adjust_stack_and_probe (max_frame_size
, true);
5343 probe_stack_range (STACK_OLD_CHECK_PROTECT
, max_frame_size
);
5346 set_insn_locations (seq
, prologue_location
);
5347 emit_insn_before (seq
, stack_check_probe_note
);
5352 /* End any sequences that failed to be closed due to syntax errors. */
5353 while (in_sequence_p ())
5356 clear_pending_stack_adjust ();
5357 do_pending_stack_adjust ();
5359 /* Output a linenumber for the end of the function.
5360 SDB depended on this. */
5361 set_curr_insn_location (input_location
);
5363 /* Before the return label (if any), clobber the return
5364 registers so that they are not propagated live to the rest of
5365 the function. This can only happen with functions that drop
5366 through; if there had been a return statement, there would
5367 have either been a return rtx, or a jump to the return label.
5369 We delay actual code generation after the current_function_value_rtx
5371 rtx_insn
*clobber_after
= get_last_insn ();
5373 /* Output the label for the actual return from the function. */
5374 emit_label (return_label
);
5376 if (targetm_common
.except_unwind_info (&global_options
) == UI_SJLJ
)
5378 /* Let except.c know where it should emit the call to unregister
5379 the function context for sjlj exceptions. */
5380 if (flag_exceptions
)
5381 sjlj_emit_function_exit_after (get_last_insn ());
5384 /* If this is an implementation of throw, do what's necessary to
5385 communicate between __builtin_eh_return and the epilogue. */
5386 expand_eh_return ();
5388 /* If stack protection is enabled for this function, check the guard. */
5389 if (crtl
->stack_protect_guard
5390 && targetm
.stack_protect_runtime_enabled_p ()
5391 && naked_return_label
== NULL_RTX
)
5392 stack_protect_epilogue ();
5394 /* If scalar return value was computed in a pseudo-reg, or was a named
5395 return value that got dumped to the stack, copy that to the hard
5397 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5399 tree decl_result
= DECL_RESULT (current_function_decl
);
5400 rtx decl_rtl
= DECL_RTL (decl_result
);
5402 if (REG_P (decl_rtl
)
5403 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
5404 : DECL_REGISTER (decl_result
))
5406 rtx real_decl_rtl
= crtl
->return_rtx
;
5409 /* This should be set in assign_parms. */
5410 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
5412 /* If this is a BLKmode structure being returned in registers,
5413 then use the mode computed in expand_return. Note that if
5414 decl_rtl is memory, then its mode may have been changed,
5415 but that crtl->return_rtx has not. */
5416 if (GET_MODE (real_decl_rtl
) == BLKmode
)
5417 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
5419 /* If a non-BLKmode return value should be padded at the least
5420 significant end of the register, shift it left by the appropriate
5421 amount. BLKmode results are handled using the group load/store
5423 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
5424 && REG_P (real_decl_rtl
)
5425 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
5427 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
5428 REGNO (real_decl_rtl
)),
5430 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
5432 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
5434 /* If expand_function_start has created a PARALLEL for decl_rtl,
5435 move the result to the real return registers. Otherwise, do
5436 a group load from decl_rtl for a named return. */
5437 if (GET_CODE (decl_rtl
) == PARALLEL
)
5438 emit_group_move (real_decl_rtl
, decl_rtl
);
5440 emit_group_load (real_decl_rtl
, decl_rtl
,
5441 TREE_TYPE (decl_result
),
5442 int_size_in_bytes (TREE_TYPE (decl_result
)));
5444 /* In the case of complex integer modes smaller than a word, we'll
5445 need to generate some non-trivial bitfield insertions. Do that
5446 on a pseudo and not the hard register. */
5447 else if (GET_CODE (decl_rtl
) == CONCAT
5448 && is_complex_int_mode (GET_MODE (decl_rtl
), &cmode
)
5449 && GET_MODE_BITSIZE (cmode
) <= BITS_PER_WORD
)
5451 int old_generating_concat_p
;
5454 old_generating_concat_p
= generating_concat_p
;
5455 generating_concat_p
= 0;
5456 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
5457 generating_concat_p
= old_generating_concat_p
;
5459 emit_move_insn (tmp
, decl_rtl
);
5460 emit_move_insn (real_decl_rtl
, tmp
);
5462 /* If a named return value dumped decl_return to memory, then
5463 we may need to re-do the PROMOTE_MODE signed/unsigned
5465 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
5467 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
5468 promote_function_mode (TREE_TYPE (decl_result
),
5469 GET_MODE (decl_rtl
), &unsignedp
,
5470 TREE_TYPE (current_function_decl
), 1);
5472 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
5475 emit_move_insn (real_decl_rtl
, decl_rtl
);
5479 /* If returning a structure, arrange to return the address of the value
5480 in a place where debuggers expect to find it.
5482 If returning a structure PCC style,
5483 the caller also depends on this value.
5484 And cfun->returns_pcc_struct is not necessarily set. */
5485 if ((cfun
->returns_struct
|| cfun
->returns_pcc_struct
)
5486 && !targetm
.calls
.omit_struct_return_reg
)
5488 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
5489 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5492 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
5493 type
= TREE_TYPE (type
);
5495 value_address
= XEXP (value_address
, 0);
5497 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
5498 current_function_decl
, true);
5500 /* Mark this as a function return value so integrate will delete the
5501 assignment and USE below when inlining this function. */
5502 REG_FUNCTION_VALUE_P (outgoing
) = 1;
5504 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5505 scalar_int_mode mode
= as_a
<scalar_int_mode
> (GET_MODE (outgoing
));
5506 value_address
= convert_memory_address (mode
, value_address
);
5508 emit_move_insn (outgoing
, value_address
);
5510 /* Show return register used to hold result (in this case the address
5512 crtl
->return_rtx
= outgoing
;
5515 /* Emit the actual code to clobber return register. Don't emit
5516 it if clobber_after is a barrier, then the previous basic block
5517 certainly doesn't fall thru into the exit block. */
5518 if (!BARRIER_P (clobber_after
))
5521 clobber_return_register ();
5522 rtx_insn
*seq
= get_insns ();
5525 emit_insn_after (seq
, clobber_after
);
5528 /* Output the label for the naked return from the function. */
5529 if (naked_return_label
)
5530 emit_label (naked_return_label
);
5532 /* @@@ This is a kludge. We want to ensure that instructions that
5533 may trap are not moved into the epilogue by scheduling, because
5534 we don't always emit unwind information for the epilogue. */
5535 if (cfun
->can_throw_non_call_exceptions
5536 && targetm_common
.except_unwind_info (&global_options
) != UI_SJLJ
)
5537 emit_insn (gen_blockage ());
5539 /* If stack protection is enabled for this function, check the guard. */
5540 if (crtl
->stack_protect_guard
5541 && targetm
.stack_protect_runtime_enabled_p ()
5542 && naked_return_label
)
5543 stack_protect_epilogue ();
5545 /* If we had calls to alloca, and this machine needs
5546 an accurate stack pointer to exit the function,
5547 insert some code to save and restore the stack pointer. */
5548 if (! EXIT_IGNORE_STACK
5549 && cfun
->calls_alloca
)
5554 emit_stack_save (SAVE_FUNCTION
, &tem
);
5555 rtx_insn
*seq
= get_insns ();
5557 emit_insn_before (seq
, parm_birth_insn
);
5559 emit_stack_restore (SAVE_FUNCTION
, tem
);
5562 /* ??? This should no longer be necessary since stupid is no longer with
5563 us, but there are some parts of the compiler (eg reload_combine, and
5564 sh mach_dep_reorg) that still try and compute their own lifetime info
5565 instead of using the general framework. */
5566 use_return_register ();
5570 get_arg_pointer_save_area (void)
5572 rtx ret
= arg_pointer_save_area
;
5576 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5577 arg_pointer_save_area
= ret
;
5580 if (! crtl
->arg_pointer_save_area_init
)
5582 /* Save the arg pointer at the beginning of the function. The
5583 generated stack slot may not be a valid memory address, so we
5584 have to check it and fix it if necessary. */
5586 emit_move_insn (validize_mem (copy_rtx (ret
)),
5587 crtl
->args
.internal_arg_pointer
);
5588 rtx_insn
*seq
= get_insns ();
5591 push_topmost_sequence ();
5592 emit_insn_after (seq
, entry_of_function ());
5593 pop_topmost_sequence ();
5595 crtl
->arg_pointer_save_area_init
= true;
5602 /* If debugging dumps are requested, dump information about how the
5603 target handled -fstack-check=clash for the prologue.
5605 PROBES describes what if any probes were emitted.
5607 RESIDUALS indicates if the prologue had any residual allocation
5608 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5611 dump_stack_clash_frame_info (enum stack_clash_probes probes
, bool residuals
)
5618 case NO_PROBE_NO_FRAME
:
5620 "Stack clash no probe no stack adjustment in prologue.\n");
5622 case NO_PROBE_SMALL_FRAME
:
5624 "Stack clash no probe small stack adjustment in prologue.\n");
5627 fprintf (dump_file
, "Stack clash inline probes in prologue.\n");
5630 fprintf (dump_file
, "Stack clash probe loop in prologue.\n");
5635 fprintf (dump_file
, "Stack clash residual allocation in prologue.\n");
5637 fprintf (dump_file
, "Stack clash no residual allocation in prologue.\n");
5639 if (frame_pointer_needed
)
5640 fprintf (dump_file
, "Stack clash frame pointer needed.\n");
5642 fprintf (dump_file
, "Stack clash no frame pointer needed.\n");
5644 if (TREE_THIS_VOLATILE (cfun
->decl
))
5646 "Stack clash noreturn prologue, assuming no implicit"
5647 " probes in caller.\n");
5650 "Stack clash not noreturn prologue.\n");
5653 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5654 for the first time. */
5657 record_insns (rtx_insn
*insns
, rtx end
, hash_table
<insn_cache_hasher
> **hashp
)
5660 hash_table
<insn_cache_hasher
> *hash
= *hashp
;
5663 *hashp
= hash
= hash_table
<insn_cache_hasher
>::create_ggc (17);
5665 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
5667 rtx
*slot
= hash
->find_slot (tmp
, INSERT
);
5668 gcc_assert (*slot
== NULL
);
5673 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5674 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5675 insn, then record COPY as well. */
5678 maybe_copy_prologue_epilogue_insn (rtx insn
, rtx copy
)
5680 hash_table
<insn_cache_hasher
> *hash
;
5683 hash
= epilogue_insn_hash
;
5684 if (!hash
|| !hash
->find (insn
))
5686 hash
= prologue_insn_hash
;
5687 if (!hash
|| !hash
->find (insn
))
5691 slot
= hash
->find_slot (copy
, INSERT
);
5692 gcc_assert (*slot
== NULL
);
5696 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5697 we can be running after reorg, SEQUENCE rtl is possible. */
5700 contains (const rtx_insn
*insn
, hash_table
<insn_cache_hasher
> *hash
)
5705 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5707 rtx_sequence
*seq
= as_a
<rtx_sequence
*> (PATTERN (insn
));
5709 for (i
= seq
->len () - 1; i
>= 0; i
--)
5710 if (hash
->find (seq
->element (i
)))
5715 return hash
->find (const_cast<rtx_insn
*> (insn
)) != NULL
;
5719 prologue_contains (const rtx_insn
*insn
)
5721 return contains (insn
, prologue_insn_hash
);
5725 epilogue_contains (const rtx_insn
*insn
)
5727 return contains (insn
, epilogue_insn_hash
);
5731 prologue_epilogue_contains (const rtx_insn
*insn
)
5733 if (contains (insn
, prologue_insn_hash
))
5735 if (contains (insn
, epilogue_insn_hash
))
5741 record_prologue_seq (rtx_insn
*seq
)
5743 record_insns (seq
, NULL
, &prologue_insn_hash
);
5747 record_epilogue_seq (rtx_insn
*seq
)
5749 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5752 /* Set JUMP_LABEL for a return insn. */
5755 set_return_jump_label (rtx_insn
*returnjump
)
5757 rtx pat
= PATTERN (returnjump
);
5758 if (GET_CODE (pat
) == PARALLEL
)
5759 pat
= XVECEXP (pat
, 0, 0);
5760 if (ANY_RETURN_P (pat
))
5761 JUMP_LABEL (returnjump
) = pat
;
5763 JUMP_LABEL (returnjump
) = ret_rtx
;
5766 /* Return a sequence to be used as the split prologue for the current
5767 function, or NULL. */
5770 make_split_prologue_seq (void)
5772 if (!flag_split_stack
5773 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun
->decl
)))
5777 emit_insn (targetm
.gen_split_stack_prologue ());
5778 rtx_insn
*seq
= get_insns ();
5781 record_insns (seq
, NULL
, &prologue_insn_hash
);
5782 set_insn_locations (seq
, prologue_location
);
5787 /* Return a sequence to be used as the prologue for the current function,
5791 make_prologue_seq (void)
5793 if (!targetm
.have_prologue ())
5797 rtx_insn
*seq
= targetm
.gen_prologue ();
5800 /* Insert an explicit USE for the frame pointer
5801 if the profiling is on and the frame pointer is required. */
5802 if (crtl
->profile
&& frame_pointer_needed
)
5803 emit_use (hard_frame_pointer_rtx
);
5805 /* Retain a map of the prologue insns. */
5806 record_insns (seq
, NULL
, &prologue_insn_hash
);
5807 emit_note (NOTE_INSN_PROLOGUE_END
);
5809 /* Ensure that instructions are not moved into the prologue when
5810 profiling is on. The call to the profiling routine can be
5811 emitted within the live range of a call-clobbered register. */
5812 if (!targetm
.profile_before_prologue () && crtl
->profile
)
5813 emit_insn (gen_blockage ());
5817 set_insn_locations (seq
, prologue_location
);
5822 /* Emit a sequence of insns to zero the call-used registers before RET
5823 according to ZERO_REGS_TYPE. */
5826 gen_call_used_regs_seq (rtx_insn
*ret
, unsigned int zero_regs_type
)
5828 bool only_gpr
= true;
5829 bool only_used
= true;
5830 bool only_arg
= true;
5832 /* No need to zero call-used-regs in main (). */
5833 if (MAIN_NAME_P (DECL_NAME (current_function_decl
)))
5836 /* No need to zero call-used-regs if __builtin_eh_return is called
5837 since it isn't a normal function return. */
5838 if (crtl
->calls_eh_return
)
5841 /* If only_gpr is true, only zero call-used registers that are
5842 general-purpose registers; if only_used is true, only zero
5843 call-used registers that are used in the current function;
5844 if only_arg is true, only zero call-used registers that pass
5845 parameters defined by the flatform's calling conversion. */
5847 using namespace zero_regs_flags
;
5849 only_gpr
= zero_regs_type
& ONLY_GPR
;
5850 only_used
= zero_regs_type
& ONLY_USED
;
5851 only_arg
= zero_regs_type
& ONLY_ARG
;
5853 /* For each of the hard registers, we should zero it if:
5854 1. it is a call-used register;
5855 and 2. it is not a fixed register;
5856 and 3. it is not live at the return of the routine;
5857 and 4. it is general registor if only_gpr is true;
5858 and 5. it is used in the routine if only_used is true;
5859 and 6. it is a register that passes parameter if only_arg is true. */
5861 /* First, prepare the data flow information. */
5862 basic_block bb
= BLOCK_FOR_INSN (ret
);
5863 auto_bitmap live_out
;
5864 bitmap_copy (live_out
, df_get_live_out (bb
));
5865 df_simulate_initialize_backwards (bb
, live_out
);
5866 df_simulate_one_insn_backwards (bb
, ret
, live_out
);
5868 HARD_REG_SET selected_hardregs
;
5869 CLEAR_HARD_REG_SET (selected_hardregs
);
5870 for (unsigned int regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
5872 if (!crtl
->abi
->clobbers_full_reg_p (regno
))
5874 if (fixed_regs
[regno
])
5876 if (REGNO_REG_SET_P (live_out
, regno
))
5879 && !TEST_HARD_REG_BIT (reg_class_contents
[GENERAL_REGS
], regno
))
5881 if (only_used
&& !df_regs_ever_live_p (regno
))
5883 if (only_arg
&& !FUNCTION_ARG_REGNO_P (regno
))
5885 #ifdef LEAF_REG_REMAP
5886 if (crtl
->uses_only_leaf_regs
&& LEAF_REG_REMAP (regno
) < 0)
5890 /* Now this is a register that we might want to zero. */
5891 SET_HARD_REG_BIT (selected_hardregs
, regno
);
5894 if (hard_reg_set_empty_p (selected_hardregs
))
5897 /* Now that we have a hard register set that needs to be zeroed, pass it to
5898 target to generate zeroing sequence. */
5899 HARD_REG_SET zeroed_hardregs
;
5901 zeroed_hardregs
= targetm
.calls
.zero_call_used_regs (selected_hardregs
);
5902 rtx_insn
*seq
= get_insns ();
5906 /* Emit the memory blockage and register clobber asm volatile before
5907 the whole sequence. */
5909 expand_asm_reg_clobber_mem_blockage (zeroed_hardregs
);
5910 rtx_insn
*seq_barrier
= get_insns ();
5913 emit_insn_before (seq_barrier
, ret
);
5914 emit_insn_before (seq
, ret
);
5916 /* Update the data flow information. */
5917 crtl
->must_be_zero_on_return
|= zeroed_hardregs
;
5918 df_set_bb_dirty (EXIT_BLOCK_PTR_FOR_FN (cfun
));
5923 /* Return a sequence to be used as the epilogue for the current function,
5927 make_epilogue_seq (void)
5929 if (!targetm
.have_epilogue ())
5933 emit_note (NOTE_INSN_EPILOGUE_BEG
);
5934 rtx_insn
*seq
= targetm
.gen_epilogue ();
5936 emit_jump_insn (seq
);
5938 /* Retain a map of the epilogue insns. */
5939 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5940 set_insn_locations (seq
, epilogue_location
);
5943 rtx_insn
*returnjump
= get_last_insn ();
5946 if (JUMP_P (returnjump
))
5947 set_return_jump_label (returnjump
);
5953 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5954 this into place with notes indicating where the prologue ends and where
5955 the epilogue begins. Update the basic block information when possible.
5957 Notes on epilogue placement:
5958 There are several kinds of edges to the exit block:
5959 * a single fallthru edge from LAST_BB
5960 * possibly, edges from blocks containing sibcalls
5961 * possibly, fake edges from infinite loops
5963 The epilogue is always emitted on the fallthru edge from the last basic
5964 block in the function, LAST_BB, into the exit block.
5966 If LAST_BB is empty except for a label, it is the target of every
5967 other basic block in the function that ends in a return. If a
5968 target has a return or simple_return pattern (possibly with
5969 conditional variants), these basic blocks can be changed so that a
5970 return insn is emitted into them, and their target is adjusted to
5971 the real exit block.
5973 Notes on shrink wrapping: We implement a fairly conservative
5974 version of shrink-wrapping rather than the textbook one. We only
5975 generate a single prologue and a single epilogue. This is
5976 sufficient to catch a number of interesting cases involving early
5979 First, we identify the blocks that require the prologue to occur before
5980 them. These are the ones that modify a call-saved register, or reference
5981 any of the stack or frame pointer registers. To simplify things, we then
5982 mark everything reachable from these blocks as also requiring a prologue.
5983 This takes care of loops automatically, and avoids the need to examine
5984 whether MEMs reference the frame, since it is sufficient to check for
5985 occurrences of the stack or frame pointer.
5987 We then compute the set of blocks for which the need for a prologue
5988 is anticipatable (borrowing terminology from the shrink-wrapping
5989 description in Muchnick's book). These are the blocks which either
5990 require a prologue themselves, or those that have only successors
5991 where the prologue is anticipatable. The prologue needs to be
5992 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5993 is not. For the moment, we ensure that only one such edge exists.
5995 The epilogue is placed as described above, but we make a
5996 distinction between inserting return and simple_return patterns
5997 when modifying other blocks that end in a return. Blocks that end
5998 in a sibcall omit the sibcall_epilogue if the block is not in
6002 thread_prologue_and_epilogue_insns (void)
6006 /* Can't deal with multiple successors of the entry block at the
6007 moment. Function should always have at least one entry
6009 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun
)));
6011 edge entry_edge
= single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
6012 edge orig_entry_edge
= entry_edge
;
6014 rtx_insn
*split_prologue_seq
= make_split_prologue_seq ();
6015 rtx_insn
*prologue_seq
= make_prologue_seq ();
6016 rtx_insn
*epilogue_seq
= make_epilogue_seq ();
6018 /* Try to perform a kind of shrink-wrapping, making sure the
6019 prologue/epilogue is emitted only around those parts of the
6020 function that require it. */
6021 try_shrink_wrapping (&entry_edge
, prologue_seq
);
6023 /* If the target can handle splitting the prologue/epilogue into separate
6024 components, try to shrink-wrap these components separately. */
6025 try_shrink_wrapping_separate (entry_edge
->dest
);
6027 /* If that did anything for any component we now need the generate the
6028 "main" prologue again. Because some targets require some of these
6029 to be called in a specific order (i386 requires the split prologue
6030 to be first, for example), we create all three sequences again here.
6031 If this does not work for some target, that target should not enable
6032 separate shrink-wrapping. */
6033 if (crtl
->shrink_wrapped_separate
)
6035 split_prologue_seq
= make_split_prologue_seq ();
6036 prologue_seq
= make_prologue_seq ();
6037 epilogue_seq
= make_epilogue_seq ();
6040 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun
));
6042 /* A small fib -- epilogue is not yet completed, but we wish to re-use
6043 this marker for the splits of EH_RETURN patterns, and nothing else
6044 uses the flag in the meantime. */
6045 epilogue_completed
= 1;
6047 /* Find non-fallthru edges that end with EH_RETURN instructions. On
6048 some targets, these get split to a special version of the epilogue
6049 code. In order to be able to properly annotate these with unwind
6050 info, try to split them now. If we get a valid split, drop an
6051 EPILOGUE_BEG note and mark the insns as epilogue insns. */
6054 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6056 rtx_insn
*prev
, *last
, *trial
;
6058 if (e
->flags
& EDGE_FALLTHRU
)
6060 last
= BB_END (e
->src
);
6061 if (!eh_returnjump_p (last
))
6064 prev
= PREV_INSN (last
);
6065 trial
= try_split (PATTERN (last
), last
, 1);
6069 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
6070 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
6073 edge exit_fallthru_edge
= find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6075 if (exit_fallthru_edge
)
6079 insert_insn_on_edge (epilogue_seq
, exit_fallthru_edge
);
6080 commit_edge_insertions ();
6082 /* The epilogue insns we inserted may cause the exit edge to no longer
6084 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6086 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
6087 && returnjump_p (BB_END (e
->src
)))
6088 e
->flags
&= ~EDGE_FALLTHRU
;
6091 else if (next_active_insn (BB_END (exit_fallthru_edge
->src
)))
6093 /* We have a fall-through edge to the exit block, the source is not
6094 at the end of the function, and there will be an assembler epilogue
6095 at the end of the function.
6096 We can't use force_nonfallthru here, because that would try to
6097 use return. Inserting a jump 'by hand' is extremely messy, so
6098 we take advantage of cfg_layout_finalize using
6099 fixup_fallthru_exit_predecessor. */
6100 cfg_layout_initialize (0);
6102 FOR_EACH_BB_FN (cur_bb
, cfun
)
6103 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
6104 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
6105 cur_bb
->aux
= cur_bb
->next_bb
;
6106 cfg_layout_finalize ();
6110 /* Insert the prologue. */
6112 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
6114 if (split_prologue_seq
|| prologue_seq
)
6116 rtx_insn
*split_prologue_insn
= split_prologue_seq
;
6117 if (split_prologue_seq
)
6119 while (split_prologue_insn
&& !NONDEBUG_INSN_P (split_prologue_insn
))
6120 split_prologue_insn
= NEXT_INSN (split_prologue_insn
);
6121 insert_insn_on_edge (split_prologue_seq
, orig_entry_edge
);
6124 rtx_insn
*prologue_insn
= prologue_seq
;
6127 while (prologue_insn
&& !NONDEBUG_INSN_P (prologue_insn
))
6128 prologue_insn
= NEXT_INSN (prologue_insn
);
6129 insert_insn_on_edge (prologue_seq
, entry_edge
);
6132 commit_edge_insertions ();
6134 /* Look for basic blocks within the prologue insns. */
6135 if (split_prologue_insn
6136 && BLOCK_FOR_INSN (split_prologue_insn
) == NULL
)
6137 split_prologue_insn
= NULL
;
6139 && BLOCK_FOR_INSN (prologue_insn
) == NULL
)
6140 prologue_insn
= NULL
;
6141 if (split_prologue_insn
|| prologue_insn
)
6143 auto_sbitmap
blocks (last_basic_block_for_fn (cfun
));
6144 bitmap_clear (blocks
);
6145 if (split_prologue_insn
)
6146 bitmap_set_bit (blocks
,
6147 BLOCK_FOR_INSN (split_prologue_insn
)->index
);
6149 bitmap_set_bit (blocks
, BLOCK_FOR_INSN (prologue_insn
)->index
);
6150 find_many_sub_basic_blocks (blocks
);
6154 default_rtl_profile ();
6156 /* Emit sibling epilogues before any sibling call sites. */
6157 for (ei
= ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6158 (e
= ei_safe_edge (ei
));
6161 /* Skip those already handled, the ones that run without prologue. */
6162 if (e
->flags
& EDGE_IGNORE
)
6164 e
->flags
&= ~EDGE_IGNORE
;
6168 rtx_insn
*insn
= BB_END (e
->src
);
6170 if (!(CALL_P (insn
) && SIBLING_CALL_P (insn
)))
6173 if (rtx_insn
*ep_seq
= targetm
.gen_sibcall_epilogue ())
6176 emit_note (NOTE_INSN_EPILOGUE_BEG
);
6178 rtx_insn
*seq
= get_insns ();
6181 /* Retain a map of the epilogue insns. Used in life analysis to
6182 avoid getting rid of sibcall epilogue insns. Do this before we
6183 actually emit the sequence. */
6184 record_insns (seq
, NULL
, &epilogue_insn_hash
);
6185 set_insn_locations (seq
, epilogue_location
);
6187 emit_insn_before (seq
, insn
);
6193 rtx_insn
*insn
, *next
;
6195 /* Similarly, move any line notes that appear after the epilogue.
6196 There is no need, however, to be quite so anal about the existence
6197 of such a note. Also possibly move
6198 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6200 for (insn
= epilogue_seq
; insn
; insn
= next
)
6202 next
= NEXT_INSN (insn
);
6204 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
6205 reorder_insns (insn
, insn
, PREV_INSN (epilogue_seq
));
6209 /* Threading the prologue and epilogue changes the artificial refs
6210 in the entry and exit blocks. */
6211 epilogue_completed
= 1;
6212 df_update_entry_exit_and_calls ();
6215 /* Reposition the prologue-end and epilogue-begin notes after
6216 instruction scheduling. */
6219 reposition_prologue_and_epilogue_notes (void)
6221 if (!targetm
.have_prologue ()
6222 && !targetm
.have_epilogue ()
6223 && !targetm
.have_sibcall_epilogue ())
6226 /* Since the hash table is created on demand, the fact that it is
6227 non-null is a signal that it is non-empty. */
6228 if (prologue_insn_hash
!= NULL
)
6230 size_t len
= prologue_insn_hash
->elements ();
6231 rtx_insn
*insn
, *last
= NULL
, *note
= NULL
;
6233 /* Scan from the beginning until we reach the last prologue insn. */
6234 /* ??? While we do have the CFG intact, there are two problems:
6235 (1) The prologue can contain loops (typically probing the stack),
6236 which means that the end of the prologue isn't in the first bb.
6237 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6238 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
6242 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
6245 else if (contains (insn
, prologue_insn_hash
))
6257 /* Scan forward looking for the PROLOGUE_END note. It should
6258 be right at the beginning of the block, possibly with other
6259 insn notes that got moved there. */
6260 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
6263 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
6268 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6270 last
= NEXT_INSN (last
);
6271 reorder_insns (note
, note
, last
);
6275 if (epilogue_insn_hash
!= NULL
)
6280 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6282 rtx_insn
*insn
, *first
= NULL
, *note
= NULL
;
6283 basic_block bb
= e
->src
;
6285 /* Scan from the beginning until we reach the first epilogue insn. */
6286 FOR_BB_INSNS (bb
, insn
)
6290 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
6297 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
6307 /* If the function has a single basic block, and no real
6308 epilogue insns (e.g. sibcall with no cleanup), the
6309 epilogue note can get scheduled before the prologue
6310 note. If we have frame related prologue insns, having
6311 them scanned during the epilogue will result in a crash.
6312 In this case re-order the epilogue note to just before
6313 the last insn in the block. */
6315 first
= BB_END (bb
);
6317 if (PREV_INSN (first
) != note
)
6318 reorder_insns (note
, note
, PREV_INSN (first
));
6324 /* Returns the name of function declared by FNDECL. */
6326 fndecl_name (tree fndecl
)
6330 return lang_hooks
.decl_printable_name (fndecl
, 1);
6333 /* Returns the name of function FN. */
6335 function_name (struct function
*fn
)
6337 tree fndecl
= (fn
== NULL
) ? NULL
: fn
->decl
;
6338 return fndecl_name (fndecl
);
6341 /* Returns the name of the current function. */
6343 current_function_name (void)
6345 return function_name (cfun
);
6350 rest_of_handle_check_leaf_regs (void)
6352 #ifdef LEAF_REGISTERS
6353 crtl
->uses_only_leaf_regs
6354 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
6359 /* Insert a TYPE into the used types hash table of CFUN. */
6362 used_types_insert_helper (tree type
, struct function
*func
)
6364 if (type
!= NULL
&& func
!= NULL
)
6366 if (func
->used_types_hash
== NULL
)
6367 func
->used_types_hash
= hash_set
<tree
>::create_ggc (37);
6369 func
->used_types_hash
->add (type
);
6373 /* Given a type, insert it into the used hash table in cfun. */
6375 used_types_insert (tree t
)
6377 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
6382 if (TREE_CODE (t
) == ERROR_MARK
)
6384 if (TYPE_NAME (t
) == NULL_TREE
6385 || TYPE_NAME (t
) == TYPE_NAME (TYPE_MAIN_VARIANT (t
)))
6386 t
= TYPE_MAIN_VARIANT (t
);
6387 if (debug_info_level
> DINFO_LEVEL_NONE
)
6390 used_types_insert_helper (t
, cfun
);
6393 /* So this might be a type referenced by a global variable.
6394 Record that type so that we can later decide to emit its
6395 debug information. */
6396 vec_safe_push (types_used_by_cur_var_decl
, t
);
6401 /* Helper to Hash a struct types_used_by_vars_entry. */
6404 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
6406 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
6408 return iterative_hash_object (entry
->type
,
6409 iterative_hash_object (entry
->var_decl
, 0));
6412 /* Hash function of the types_used_by_vars_entry hash table. */
6415 used_type_hasher::hash (types_used_by_vars_entry
*entry
)
6417 return hash_types_used_by_vars_entry (entry
);
6420 /*Equality function of the types_used_by_vars_entry hash table. */
6423 used_type_hasher::equal (types_used_by_vars_entry
*e1
,
6424 types_used_by_vars_entry
*e2
)
6426 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
6429 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6432 types_used_by_var_decl_insert (tree type
, tree var_decl
)
6434 if (type
!= NULL
&& var_decl
!= NULL
)
6436 types_used_by_vars_entry
**slot
;
6437 struct types_used_by_vars_entry e
;
6438 e
.var_decl
= var_decl
;
6440 if (types_used_by_vars_hash
== NULL
)
6441 types_used_by_vars_hash
6442 = hash_table
<used_type_hasher
>::create_ggc (37);
6444 slot
= types_used_by_vars_hash
->find_slot (&e
, INSERT
);
6447 struct types_used_by_vars_entry
*entry
;
6448 entry
= ggc_alloc
<types_used_by_vars_entry
> ();
6450 entry
->var_decl
= var_decl
;
6458 const pass_data pass_data_leaf_regs
=
6460 RTL_PASS
, /* type */
6461 "*leaf_regs", /* name */
6462 OPTGROUP_NONE
, /* optinfo_flags */
6463 TV_NONE
, /* tv_id */
6464 0, /* properties_required */
6465 0, /* properties_provided */
6466 0, /* properties_destroyed */
6467 0, /* todo_flags_start */
6468 0, /* todo_flags_finish */
6471 class pass_leaf_regs
: public rtl_opt_pass
6474 pass_leaf_regs (gcc::context
*ctxt
)
6475 : rtl_opt_pass (pass_data_leaf_regs
, ctxt
)
6478 /* opt_pass methods: */
6479 virtual unsigned int execute (function
*)
6481 return rest_of_handle_check_leaf_regs ();
6484 }; // class pass_leaf_regs
6489 make_pass_leaf_regs (gcc::context
*ctxt
)
6491 return new pass_leaf_regs (ctxt
);
6495 rest_of_handle_thread_prologue_and_epilogue (void)
6497 /* prepare_shrink_wrap is sensitive to the block structure of the control
6498 flow graph, so clean it up first. */
6502 /* On some machines, the prologue and epilogue code, or parts thereof,
6503 can be represented as RTL. Doing so lets us schedule insns between
6504 it and the rest of the code and also allows delayed branch
6505 scheduling to operate in the epilogue. */
6506 thread_prologue_and_epilogue_insns ();
6508 /* Some non-cold blocks may now be only reachable from cold blocks.
6510 fixup_partitions ();
6512 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6514 cleanup_cfg (optimize
? CLEANUP_EXPENSIVE
: 0);
6516 /* The stack usage info is finalized during prologue expansion. */
6517 if (flag_stack_usage_info
|| flag_callgraph_info
)
6518 output_stack_usage ();
6523 /* Record a final call to CALLEE at LOCATION. */
6526 record_final_call (tree callee
, location_t location
)
6528 struct callinfo_callee datum
= { location
, callee
};
6529 vec_safe_push (cfun
->su
->callees
, datum
);
6532 /* Record a dynamic allocation made for DECL_OR_EXP. */
6535 record_dynamic_alloc (tree decl_or_exp
)
6537 struct callinfo_dalloc datum
;
6539 if (DECL_P (decl_or_exp
))
6541 datum
.location
= DECL_SOURCE_LOCATION (decl_or_exp
);
6542 const char *name
= lang_hooks
.decl_printable_name (decl_or_exp
, 2);
6543 const char *dot
= strrchr (name
, '.');
6546 datum
.name
= ggc_strdup (name
);
6550 datum
.location
= EXPR_LOCATION (decl_or_exp
);
6554 vec_safe_push (cfun
->su
->dallocs
, datum
);
6559 const pass_data pass_data_thread_prologue_and_epilogue
=
6561 RTL_PASS
, /* type */
6562 "pro_and_epilogue", /* name */
6563 OPTGROUP_NONE
, /* optinfo_flags */
6564 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
6565 0, /* properties_required */
6566 0, /* properties_provided */
6567 0, /* properties_destroyed */
6568 0, /* todo_flags_start */
6569 ( TODO_df_verify
| TODO_df_finish
), /* todo_flags_finish */
6572 class pass_thread_prologue_and_epilogue
: public rtl_opt_pass
6575 pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
6576 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue
, ctxt
)
6579 /* opt_pass methods: */
6580 virtual unsigned int execute (function
*)
6582 return rest_of_handle_thread_prologue_and_epilogue ();
6585 }; // class pass_thread_prologue_and_epilogue
6590 make_pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
6592 return new pass_thread_prologue_and_epilogue (ctxt
);
6597 const pass_data pass_data_zero_call_used_regs
=
6599 RTL_PASS
, /* type */
6600 "zero_call_used_regs", /* name */
6601 OPTGROUP_NONE
, /* optinfo_flags */
6602 TV_NONE
, /* tv_id */
6603 0, /* properties_required */
6604 0, /* properties_provided */
6605 0, /* properties_destroyed */
6606 0, /* todo_flags_start */
6607 0, /* todo_flags_finish */
6610 class pass_zero_call_used_regs
: public rtl_opt_pass
6613 pass_zero_call_used_regs (gcc::context
*ctxt
)
6614 : rtl_opt_pass (pass_data_zero_call_used_regs
, ctxt
)
6617 /* opt_pass methods: */
6618 virtual unsigned int execute (function
*);
6620 }; // class pass_zero_call_used_regs
6623 pass_zero_call_used_regs::execute (function
*fun
)
6625 using namespace zero_regs_flags
;
6626 unsigned int zero_regs_type
= UNSET
;
6628 tree attr_zero_regs
= lookup_attribute ("zero_call_used_regs",
6629 DECL_ATTRIBUTES (fun
->decl
));
6631 /* Get the type of zero_call_used_regs from function attribute.
6632 We have filtered out invalid attribute values already at this point. */
6635 /* The TREE_VALUE of an attribute is a TREE_LIST whose TREE_VALUE
6636 is the attribute argument's value. */
6637 attr_zero_regs
= TREE_VALUE (attr_zero_regs
);
6638 gcc_assert (TREE_CODE (attr_zero_regs
) == TREE_LIST
);
6639 attr_zero_regs
= TREE_VALUE (attr_zero_regs
);
6640 gcc_assert (TREE_CODE (attr_zero_regs
) == STRING_CST
);
6642 for (unsigned int i
= 0; zero_call_used_regs_opts
[i
].name
!= NULL
; ++i
)
6643 if (strcmp (TREE_STRING_POINTER (attr_zero_regs
),
6644 zero_call_used_regs_opts
[i
].name
) == 0)
6646 zero_regs_type
= zero_call_used_regs_opts
[i
].flag
;
6651 if (!zero_regs_type
)
6652 zero_regs_type
= flag_zero_call_used_regs
;
6654 /* No need to zero call-used-regs when no user request is present. */
6655 if (!(zero_regs_type
& ENABLED
))
6661 /* This pass needs data flow information. */
6664 /* Iterate over the function's return instructions and insert any
6665 register zeroing required by the -fzero-call-used-regs command-line
6666 option or the "zero_call_used_regs" function attribute. */
6667 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6669 rtx_insn
*insn
= BB_END (e
->src
);
6670 if (JUMP_P (insn
) && ANY_RETURN_P (JUMP_LABEL (insn
)))
6671 gen_call_used_regs_seq (insn
, zero_regs_type
);
6680 make_pass_zero_call_used_regs (gcc::context
*ctxt
)
6682 return new pass_zero_call_used_regs (ctxt
);
6685 /* If CONSTRAINT is a matching constraint, then return its number.
6686 Otherwise, return -1. */
6689 matching_constraint_num (const char *constraint
)
6691 if (*constraint
== '%')
6694 if (IN_RANGE (*constraint
, '0', '9'))
6695 return strtoul (constraint
, NULL
, 10);
6700 /* This mini-pass fixes fall-out from SSA in asm statements that have
6701 in-out constraints. Say you start with
6704 asm ("": "+mr" (inout));
6707 which is transformed very early to use explicit output and match operands:
6710 asm ("": "=mr" (inout) : "0" (inout));
6713 Or, after SSA and copyprop,
6715 asm ("": "=mr" (inout_2) : "0" (inout_1));
6718 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6719 they represent two separate values, so they will get different pseudo
6720 registers during expansion. Then, since the two operands need to match
6721 per the constraints, but use different pseudo registers, reload can
6722 only register a reload for these operands. But reloads can only be
6723 satisfied by hardregs, not by memory, so we need a register for this
6724 reload, just because we are presented with non-matching operands.
6725 So, even though we allow memory for this operand, no memory can be
6726 used for it, just because the two operands don't match. This can
6727 cause reload failures on register-starved targets.
6729 So it's a symptom of reload not being able to use memory for reloads
6730 or, alternatively it's also a symptom of both operands not coming into
6731 reload as matching (in which case the pseudo could go to memory just
6732 fine, as the alternative allows it, and no reload would be necessary).
6733 We fix the latter problem here, by transforming
6735 asm ("": "=mr" (inout_2) : "0" (inout_1));
6740 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6743 match_asm_constraints_1 (rtx_insn
*insn
, rtx
*p_sets
, int noutputs
)
6746 bool changed
= false;
6747 rtx op
= SET_SRC (p_sets
[0]);
6748 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
6749 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
6750 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
6752 memset (output_matched
, 0, noutputs
* sizeof (bool));
6753 for (i
= 0; i
< ninputs
; i
++)
6757 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
6760 match
= matching_constraint_num (constraint
);
6764 gcc_assert (match
< noutputs
);
6765 output
= SET_DEST (p_sets
[match
]);
6766 input
= RTVEC_ELT (inputs
, i
);
6767 /* Only do the transformation for pseudos. */
6768 if (! REG_P (output
)
6769 || rtx_equal_p (output
, input
)
6770 || !(REG_P (input
) || SUBREG_P (input
)
6771 || MEM_P (input
) || CONSTANT_P (input
))
6772 || !general_operand (input
, GET_MODE (output
)))
6775 /* We can't do anything if the output is also used as input,
6776 as we're going to overwrite it. */
6777 for (j
= 0; j
< ninputs
; j
++)
6778 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
6783 /* Avoid changing the same input several times. For
6784 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6785 only change it once (to out1), rather than changing it
6786 first to out1 and afterwards to out2. */
6789 for (j
= 0; j
< noutputs
; j
++)
6790 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
6795 output_matched
[match
] = true;
6798 emit_move_insn (output
, copy_rtx (input
));
6799 insns
= get_insns ();
6801 emit_insn_before (insns
, insn
);
6803 constraint
= ASM_OPERANDS_OUTPUT_CONSTRAINT(SET_SRC(p_sets
[match
]));
6804 bool early_clobber_p
= strchr (constraint
, '&') != NULL
;
6806 /* Now replace all mentions of the input with output. We can't
6807 just replace the occurrence in inputs[i], as the register might
6808 also be used in some other input (or even in an address of an
6809 output), which would mean possibly increasing the number of
6810 inputs by one (namely 'output' in addition), which might pose
6811 a too complicated problem for reload to solve. E.g. this situation:
6813 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6815 Here 'input' is used in two occurrences as input (once for the
6816 input operand, once for the address in the second output operand).
6817 If we would replace only the occurrence of the input operand (to
6818 make the matching) we would be left with this:
6821 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6823 Now we suddenly have two different input values (containing the same
6824 value, but different pseudos) where we formerly had only one.
6825 With more complicated asms this might lead to reload failures
6826 which wouldn't have happen without this pass. So, iterate over
6827 all operands and replace all occurrences of the register used.
6829 However, if one or more of the 'input' uses have a non-matching
6830 constraint and the matched output operand is an early clobber
6831 operand, then do not replace the input operand, since by definition
6832 it conflicts with the output operand and cannot share the same
6833 register. See PR89313 for details. */
6835 for (j
= 0; j
< noutputs
; j
++)
6836 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
6837 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
6838 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
6840 for (j
= 0; j
< ninputs
; j
++)
6841 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
6843 if (!early_clobber_p
6844 || match
== matching_constraint_num
6845 (ASM_OPERANDS_INPUT_CONSTRAINT (op
, j
)))
6846 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
6854 df_insn_rescan (insn
);
6857 /* Add the decl D to the local_decls list of FUN. */
6860 add_local_decl (struct function
*fun
, tree d
)
6862 gcc_assert (VAR_P (d
));
6863 vec_safe_push (fun
->local_decls
, d
);
6868 const pass_data pass_data_match_asm_constraints
=
6870 RTL_PASS
, /* type */
6871 "asmcons", /* name */
6872 OPTGROUP_NONE
, /* optinfo_flags */
6873 TV_NONE
, /* tv_id */
6874 0, /* properties_required */
6875 0, /* properties_provided */
6876 0, /* properties_destroyed */
6877 0, /* todo_flags_start */
6878 0, /* todo_flags_finish */
6881 class pass_match_asm_constraints
: public rtl_opt_pass
6884 pass_match_asm_constraints (gcc::context
*ctxt
)
6885 : rtl_opt_pass (pass_data_match_asm_constraints
, ctxt
)
6888 /* opt_pass methods: */
6889 virtual unsigned int execute (function
*);
6891 }; // class pass_match_asm_constraints
6894 pass_match_asm_constraints::execute (function
*fun
)
6901 if (!crtl
->has_asm_statement
)
6904 df_set_flags (DF_DEFER_INSN_RESCAN
);
6905 FOR_EACH_BB_FN (bb
, fun
)
6907 FOR_BB_INSNS (bb
, insn
)
6912 pat
= PATTERN (insn
);
6913 if (GET_CODE (pat
) == PARALLEL
)
6914 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
6915 else if (GET_CODE (pat
) == SET
)
6916 p_sets
= &PATTERN (insn
), noutputs
= 1;
6920 if (GET_CODE (*p_sets
) == SET
6921 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
6922 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
6926 return TODO_df_finish
;
6932 make_pass_match_asm_constraints (gcc::context
*ctxt
)
6934 return new pass_match_asm_constraints (ctxt
);
6938 #include "gt-function.h"