1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2020 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 duplicat e them because we don't have the
2210 function_result_decl to test. */
2211 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2213 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2216 /* We don't set DECL_REGISTER for the function_result_decl. */
2220 /* Only register-like things go in registers. */
2221 if (DECL_MODE (decl
) == BLKmode
)
2224 /* If -ffloat-store specified, don't put explicit float variables
2226 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2227 propagates values across these stores, and it probably shouldn't. */
2228 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
2231 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2234 /* If we're not interested in tracking debugging information for
2235 this decl, then we can certainly put it in a register. */
2236 if (DECL_IGNORED_P (decl
))
2242 /* Thunks force a tail call even at -O0 so we need to avoid creating a
2243 dangling reference in case the parameter is passed by reference. */
2244 if (TREE_CODE (decl
) == PARM_DECL
&& cfun
->tail_call_marked
)
2247 if (!DECL_REGISTER (decl
))
2250 /* When not optimizing, disregard register keyword for types that
2251 could have methods, otherwise the methods won't be callable from
2253 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl
)))
2259 /* Structures to communicate between the subroutines of assign_parms.
2260 The first holds data persistent across all parameters, the second
2261 is cleared out for each parameter. */
2263 struct assign_parm_data_all
2265 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2266 should become a job of the target or otherwise encapsulated. */
2267 CUMULATIVE_ARGS args_so_far_v
;
2268 cumulative_args_t args_so_far
;
2269 struct args_size stack_args_size
;
2270 tree function_result_decl
;
2272 rtx_insn
*first_conversion_insn
;
2273 rtx_insn
*last_conversion_insn
;
2274 HOST_WIDE_INT pretend_args_size
;
2275 HOST_WIDE_INT extra_pretend_bytes
;
2276 int reg_parm_stack_space
;
2279 struct assign_parm_data_one
2282 function_arg_info arg
;
2285 machine_mode nominal_mode
;
2286 machine_mode passed_mode
;
2287 struct locate_and_pad_arg_data locate
;
2291 /* A subroutine of assign_parms. Initialize ALL. */
2294 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2296 tree fntype ATTRIBUTE_UNUSED
;
2298 memset (all
, 0, sizeof (*all
));
2300 fntype
= TREE_TYPE (current_function_decl
);
2302 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2303 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
);
2305 INIT_CUMULATIVE_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
,
2306 current_function_decl
, -1);
2308 all
->args_so_far
= pack_cumulative_args (&all
->args_so_far_v
);
2310 #ifdef INCOMING_REG_PARM_STACK_SPACE
2311 all
->reg_parm_stack_space
2312 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl
);
2316 /* If ARGS contains entries with complex types, split the entry into two
2317 entries of the component type. Return a new list of substitutions are
2318 needed, else the old list. */
2321 split_complex_args (vec
<tree
> *args
)
2326 FOR_EACH_VEC_ELT (*args
, i
, p
)
2328 tree type
= TREE_TYPE (p
);
2329 if (TREE_CODE (type
) == COMPLEX_TYPE
2330 && targetm
.calls
.split_complex_arg (type
))
2333 tree subtype
= TREE_TYPE (type
);
2334 bool addressable
= TREE_ADDRESSABLE (p
);
2336 /* Rewrite the PARM_DECL's type with its component. */
2338 TREE_TYPE (p
) = subtype
;
2339 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2340 SET_DECL_MODE (p
, VOIDmode
);
2341 DECL_SIZE (p
) = NULL
;
2342 DECL_SIZE_UNIT (p
) = NULL
;
2343 /* If this arg must go in memory, put it in a pseudo here.
2344 We can't allow it to go in memory as per normal parms,
2345 because the usual place might not have the imag part
2346 adjacent to the real part. */
2347 DECL_ARTIFICIAL (p
) = addressable
;
2348 DECL_IGNORED_P (p
) = addressable
;
2349 TREE_ADDRESSABLE (p
) = 0;
2353 /* Build a second synthetic decl. */
2354 decl
= build_decl (EXPR_LOCATION (p
),
2355 PARM_DECL
, NULL_TREE
, subtype
);
2356 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2357 DECL_ARTIFICIAL (decl
) = addressable
;
2358 DECL_IGNORED_P (decl
) = addressable
;
2359 layout_decl (decl
, 0);
2360 args
->safe_insert (++i
, decl
);
2365 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2366 the hidden struct return argument, and (abi willing) complex args.
2367 Return the new parameter list. */
2370 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2372 tree fndecl
= current_function_decl
;
2373 tree fntype
= TREE_TYPE (fndecl
);
2374 vec
<tree
> fnargs
= vNULL
;
2377 for (arg
= DECL_ARGUMENTS (fndecl
); arg
; arg
= DECL_CHAIN (arg
))
2378 fnargs
.safe_push (arg
);
2380 all
->orig_fnargs
= DECL_ARGUMENTS (fndecl
);
2382 /* If struct value address is treated as the first argument, make it so. */
2383 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2384 && ! cfun
->returns_pcc_struct
2385 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2387 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2390 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2391 PARM_DECL
, get_identifier (".result_ptr"), type
);
2392 DECL_ARG_TYPE (decl
) = type
;
2393 DECL_ARTIFICIAL (decl
) = 1;
2394 DECL_NAMELESS (decl
) = 1;
2395 TREE_CONSTANT (decl
) = 1;
2396 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2397 changes, the end of the RESULT_DECL handling block in
2398 use_register_for_decl must be adjusted to match. */
2400 DECL_CHAIN (decl
) = all
->orig_fnargs
;
2401 all
->orig_fnargs
= decl
;
2402 fnargs
.safe_insert (0, decl
);
2404 all
->function_result_decl
= decl
;
2407 /* If the target wants to split complex arguments into scalars, do so. */
2408 if (targetm
.calls
.split_complex_arg
)
2409 split_complex_args (&fnargs
);
2414 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2415 data for the parameter. Incorporate ABI specifics such as pass-by-
2416 reference and type promotion. */
2419 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2420 struct assign_parm_data_one
*data
)
2424 #ifndef BROKEN_VALUE_INITIALIZATION
2425 *data
= assign_parm_data_one ();
2427 /* Old versions of GCC used to miscompile the above by only initializing
2428 the members with explicit constructors and copying garbage
2429 to the other members. */
2430 assign_parm_data_one zero_data
= {};
2434 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2436 data
->arg
.named
= 1; /* No variadic parms. */
2437 else if (DECL_CHAIN (parm
))
2438 data
->arg
.named
= 1; /* Not the last non-variadic parm. */
2439 else if (targetm
.calls
.strict_argument_naming (all
->args_so_far
))
2440 data
->arg
.named
= 1; /* Only variadic ones are unnamed. */
2442 data
->arg
.named
= 0; /* Treat as variadic. */
2444 data
->nominal_type
= TREE_TYPE (parm
);
2445 data
->arg
.type
= DECL_ARG_TYPE (parm
);
2447 /* Look out for errors propagating this far. Also, if the parameter's
2448 type is void then its value doesn't matter. */
2449 if (TREE_TYPE (parm
) == error_mark_node
2450 /* This can happen after weird syntax errors
2451 or if an enum type is defined among the parms. */
2452 || TREE_CODE (parm
) != PARM_DECL
2453 || data
->arg
.type
== NULL
2454 || VOID_TYPE_P (data
->nominal_type
))
2456 data
->nominal_type
= data
->arg
.type
= void_type_node
;
2457 data
->nominal_mode
= data
->passed_mode
= data
->arg
.mode
= VOIDmode
;
2461 /* Find mode of arg as it is passed, and mode of arg as it should be
2462 during execution of this function. */
2463 data
->passed_mode
= data
->arg
.mode
= TYPE_MODE (data
->arg
.type
);
2464 data
->nominal_mode
= TYPE_MODE (data
->nominal_type
);
2466 /* If the parm is to be passed as a transparent union or record, use the
2467 type of the first field for the tests below. We have already verified
2468 that the modes are the same. */
2469 if (RECORD_OR_UNION_TYPE_P (data
->arg
.type
)
2470 && TYPE_TRANSPARENT_AGGR (data
->arg
.type
))
2471 data
->arg
.type
= TREE_TYPE (first_field (data
->arg
.type
));
2473 /* See if this arg was passed by invisible reference. */
2474 if (apply_pass_by_reference_rules (&all
->args_so_far_v
, data
->arg
))
2476 data
->nominal_type
= data
->arg
.type
;
2477 data
->passed_mode
= data
->nominal_mode
= data
->arg
.mode
;
2480 /* Find mode as it is passed by the ABI. */
2481 unsignedp
= TYPE_UNSIGNED (data
->arg
.type
);
2483 = promote_function_mode (data
->arg
.type
, data
->arg
.mode
, &unsignedp
,
2484 TREE_TYPE (current_function_decl
), 0);
2487 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2490 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2491 struct assign_parm_data_one
*data
, bool no_rtl
)
2493 int varargs_pretend_bytes
= 0;
2495 function_arg_info last_named_arg
= data
->arg
;
2496 last_named_arg
.named
= true;
2497 targetm
.calls
.setup_incoming_varargs (all
->args_so_far
, last_named_arg
,
2498 &varargs_pretend_bytes
, no_rtl
);
2500 /* If the back-end has requested extra stack space, record how much is
2501 needed. Do not change pretend_args_size otherwise since it may be
2502 nonzero from an earlier partial argument. */
2503 if (varargs_pretend_bytes
> 0)
2504 all
->pretend_args_size
= varargs_pretend_bytes
;
2507 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2508 the incoming location of the current parameter. */
2511 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2512 struct assign_parm_data_one
*data
)
2514 HOST_WIDE_INT pretend_bytes
= 0;
2518 if (data
->arg
.mode
== VOIDmode
)
2520 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2524 targetm
.calls
.warn_parameter_passing_abi (all
->args_so_far
,
2527 entry_parm
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2529 if (entry_parm
== 0)
2530 data
->arg
.mode
= data
->passed_mode
;
2532 /* Determine parm's home in the stack, in case it arrives in the stack
2533 or we should pretend it did. Compute the stack position and rtx where
2534 the argument arrives and its size.
2536 There is one complexity here: If this was a parameter that would
2537 have been passed in registers, but wasn't only because it is
2538 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2539 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2540 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2541 as it was the previous time. */
2542 in_regs
= (entry_parm
!= 0);
2543 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2546 if (!in_regs
&& !data
->arg
.named
)
2548 if (targetm
.calls
.pretend_outgoing_varargs_named (all
->args_so_far
))
2551 function_arg_info named_arg
= data
->arg
;
2552 named_arg
.named
= true;
2553 tem
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2555 in_regs
= tem
!= NULL
;
2559 /* If this parameter was passed both in registers and in the stack, use
2560 the copy on the stack. */
2561 if (targetm
.calls
.must_pass_in_stack (data
->arg
))
2568 partial
= targetm
.calls
.arg_partial_bytes (all
->args_so_far
, data
->arg
);
2569 data
->partial
= partial
;
2571 /* The caller might already have allocated stack space for the
2572 register parameters. */
2573 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2575 /* Part of this argument is passed in registers and part
2576 is passed on the stack. Ask the prologue code to extend
2577 the stack part so that we can recreate the full value.
2579 PRETEND_BYTES is the size of the registers we need to store.
2580 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2581 stack space that the prologue should allocate.
2583 Internally, gcc assumes that the argument pointer is aligned
2584 to STACK_BOUNDARY bits. This is used both for alignment
2585 optimizations (see init_emit) and to locate arguments that are
2586 aligned to more than PARM_BOUNDARY bits. We must preserve this
2587 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2588 a stack boundary. */
2590 /* We assume at most one partial arg, and it must be the first
2591 argument on the stack. */
2592 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2594 pretend_bytes
= partial
;
2595 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2597 /* We want to align relative to the actual stack pointer, so
2598 don't include this in the stack size until later. */
2599 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2603 locate_and_pad_parm (data
->arg
.mode
, data
->arg
.type
, in_regs
,
2604 all
->reg_parm_stack_space
,
2605 entry_parm
? data
->partial
: 0, current_function_decl
,
2606 &all
->stack_args_size
, &data
->locate
);
2608 /* Update parm_stack_boundary if this parameter is passed in the
2610 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2611 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2613 /* Adjust offsets to include the pretend args. */
2614 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2615 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2616 data
->locate
.offset
.constant
+= pretend_bytes
;
2618 data
->entry_parm
= entry_parm
;
2621 /* A subroutine of assign_parms. If there is actually space on the stack
2622 for this parm, count it in stack_args_size and return true. */
2625 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2626 struct assign_parm_data_one
*data
)
2628 /* Trivially true if we've no incoming register. */
2629 if (data
->entry_parm
== NULL
)
2631 /* Also true if we're partially in registers and partially not,
2632 since we've arranged to drop the entire argument on the stack. */
2633 else if (data
->partial
!= 0)
2635 /* Also true if the target says that it's passed in both registers
2636 and on the stack. */
2637 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2638 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2640 /* Also true if the target says that there's stack allocated for
2641 all register parameters. */
2642 else if (all
->reg_parm_stack_space
> 0)
2644 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2648 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2649 if (data
->locate
.size
.var
)
2650 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2655 /* A subroutine of assign_parms. Given that this parameter is allocated
2656 stack space by the ABI, find it. */
2659 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2661 rtx offset_rtx
, stack_parm
;
2662 unsigned int align
, boundary
;
2664 /* If we're passing this arg using a reg, make its stack home the
2665 aligned stack slot. */
2666 if (data
->entry_parm
)
2667 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2669 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2671 stack_parm
= crtl
->args
.internal_arg_pointer
;
2672 if (offset_rtx
!= const0_rtx
)
2673 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2674 stack_parm
= gen_rtx_MEM (data
->arg
.mode
, stack_parm
);
2676 if (!data
->arg
.pass_by_reference
)
2678 set_mem_attributes (stack_parm
, parm
, 1);
2679 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2680 while promoted mode's size is needed. */
2681 if (data
->arg
.mode
!= BLKmode
2682 && data
->arg
.mode
!= DECL_MODE (parm
))
2684 set_mem_size (stack_parm
, GET_MODE_SIZE (data
->arg
.mode
));
2685 if (MEM_EXPR (stack_parm
) && MEM_OFFSET_KNOWN_P (stack_parm
))
2687 poly_int64 offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2689 if (maybe_ne (offset
, 0))
2690 set_mem_offset (stack_parm
, MEM_OFFSET (stack_parm
) - offset
);
2695 boundary
= data
->locate
.boundary
;
2696 align
= BITS_PER_UNIT
;
2698 /* If we're padding upward, we know that the alignment of the slot
2699 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2700 intentionally forcing upward padding. Otherwise we have to come
2701 up with a guess at the alignment based on OFFSET_RTX. */
2703 if (data
->locate
.where_pad
== PAD_NONE
|| data
->entry_parm
)
2705 else if (data
->locate
.where_pad
== PAD_UPWARD
)
2708 /* If the argument offset is actually more aligned than the nominal
2709 stack slot boundary, take advantage of that excess alignment.
2710 Don't make any assumptions if STACK_POINTER_OFFSET is in use. */
2711 if (poly_int_rtx_p (offset_rtx
, &offset
)
2712 && known_eq (STACK_POINTER_OFFSET
, 0))
2714 unsigned int offset_align
= known_alignment (offset
) * BITS_PER_UNIT
;
2715 if (offset_align
== 0 || offset_align
> STACK_BOUNDARY
)
2716 offset_align
= STACK_BOUNDARY
;
2717 align
= MAX (align
, offset_align
);
2720 else if (poly_int_rtx_p (offset_rtx
, &offset
))
2722 align
= least_bit_hwi (boundary
);
2723 unsigned int offset_align
= known_alignment (offset
) * BITS_PER_UNIT
;
2724 if (offset_align
!= 0)
2725 align
= MIN (align
, offset_align
);
2727 set_mem_align (stack_parm
, align
);
2729 if (data
->entry_parm
)
2730 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2732 data
->stack_parm
= stack_parm
;
2735 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2736 always valid and contiguous. */
2739 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2741 rtx entry_parm
= data
->entry_parm
;
2742 rtx stack_parm
= data
->stack_parm
;
2744 /* If this parm was passed part in regs and part in memory, pretend it
2745 arrived entirely in memory by pushing the register-part onto the stack.
2746 In the special case of a DImode or DFmode that is split, we could put
2747 it together in a pseudoreg directly, but for now that's not worth
2749 if (data
->partial
!= 0)
2751 /* Handle calls that pass values in multiple non-contiguous
2752 locations. The Irix 6 ABI has examples of this. */
2753 if (GET_CODE (entry_parm
) == PARALLEL
)
2754 emit_group_store (validize_mem (copy_rtx (stack_parm
)), entry_parm
,
2755 data
->arg
.type
, int_size_in_bytes (data
->arg
.type
));
2758 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2759 move_block_from_reg (REGNO (entry_parm
),
2760 validize_mem (copy_rtx (stack_parm
)),
2761 data
->partial
/ UNITS_PER_WORD
);
2764 entry_parm
= stack_parm
;
2767 /* If we didn't decide this parm came in a register, by default it came
2769 else if (entry_parm
== NULL
)
2770 entry_parm
= stack_parm
;
2772 /* When an argument is passed in multiple locations, we can't make use
2773 of this information, but we can save some copying if the whole argument
2774 is passed in a single register. */
2775 else if (GET_CODE (entry_parm
) == PARALLEL
2776 && data
->nominal_mode
!= BLKmode
2777 && data
->passed_mode
!= BLKmode
)
2779 size_t i
, len
= XVECLEN (entry_parm
, 0);
2781 for (i
= 0; i
< len
; i
++)
2782 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2783 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2784 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2785 == data
->passed_mode
)
2786 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2788 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2793 data
->entry_parm
= entry_parm
;
2796 /* A subroutine of assign_parms. Reconstitute any values which were
2797 passed in multiple registers and would fit in a single register. */
2800 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2802 rtx entry_parm
= data
->entry_parm
;
2804 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2805 This can be done with register operations rather than on the
2806 stack, even if we will store the reconstituted parameter on the
2808 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2810 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2811 emit_group_store (parmreg
, entry_parm
, data
->arg
.type
,
2812 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2813 entry_parm
= parmreg
;
2816 data
->entry_parm
= entry_parm
;
2819 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2820 always valid and properly aligned. */
2823 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2825 rtx stack_parm
= data
->stack_parm
;
2827 /* If we can't trust the parm stack slot to be aligned enough for its
2828 ultimate type, don't use that slot after entry. We'll make another
2829 stack slot, if we need one. */
2831 && ((GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
)
2832 && ((optab_handler (movmisalign_optab
, data
->nominal_mode
)
2833 != CODE_FOR_nothing
)
2834 || targetm
.slow_unaligned_access (data
->nominal_mode
,
2835 MEM_ALIGN (stack_parm
))))
2836 || (data
->nominal_type
2837 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2838 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2841 /* If parm was passed in memory, and we need to convert it on entry,
2842 don't store it back in that same slot. */
2843 else if (data
->entry_parm
== stack_parm
2844 && data
->nominal_mode
!= BLKmode
2845 && data
->nominal_mode
!= data
->passed_mode
)
2848 /* If stack protection is in effect for this function, don't leave any
2849 pointers in their passed stack slots. */
2850 else if (crtl
->stack_protect_guard
2851 && (flag_stack_protect
== SPCT_FLAG_ALL
2852 || data
->arg
.pass_by_reference
2853 || POINTER_TYPE_P (data
->nominal_type
)))
2856 data
->stack_parm
= stack_parm
;
2859 /* A subroutine of assign_parms. Return true if the current parameter
2860 should be stored as a BLKmode in the current frame. */
2863 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2865 if (data
->nominal_mode
== BLKmode
)
2867 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2870 #ifdef BLOCK_REG_PADDING
2871 /* Only assign_parm_setup_block knows how to deal with register arguments
2872 that are padded at the least significant end. */
2873 if (REG_P (data
->entry_parm
)
2874 && known_lt (GET_MODE_SIZE (data
->arg
.mode
), UNITS_PER_WORD
)
2875 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->arg
.type
, 1)
2876 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
2883 /* A subroutine of assign_parms. Arrange for the parameter to be
2884 present and valid in DATA->STACK_RTL. */
2887 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2888 tree parm
, struct assign_parm_data_one
*data
)
2890 rtx entry_parm
= data
->entry_parm
;
2891 rtx stack_parm
= data
->stack_parm
;
2892 rtx target_reg
= NULL_RTX
;
2893 bool in_conversion_seq
= false;
2895 HOST_WIDE_INT size_stored
;
2897 if (GET_CODE (entry_parm
) == PARALLEL
)
2898 entry_parm
= emit_group_move_into_temps (entry_parm
);
2900 /* If we want the parameter in a pseudo, don't use a stack slot. */
2901 if (is_gimple_reg (parm
) && use_register_for_decl (parm
))
2903 tree def
= ssa_default_def (cfun
, parm
);
2905 machine_mode mode
= promote_ssa_mode (def
, NULL
);
2906 rtx reg
= gen_reg_rtx (mode
);
2907 if (GET_CODE (reg
) != CONCAT
)
2912 /* Avoid allocating a stack slot, if there isn't one
2913 preallocated by the ABI. It might seem like we should
2914 always prefer a pseudo, but converting between
2915 floating-point and integer modes goes through the stack
2916 on various machines, so it's better to use the reserved
2917 stack slot than to risk wasting it and allocating more
2918 for the conversion. */
2919 if (stack_parm
== NULL_RTX
)
2921 int save
= generating_concat_p
;
2922 generating_concat_p
= 0;
2923 stack_parm
= gen_reg_rtx (mode
);
2924 generating_concat_p
= save
;
2927 data
->stack_parm
= NULL
;
2930 size
= int_size_in_bytes (data
->arg
.type
);
2931 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2932 if (stack_parm
== 0)
2934 HOST_WIDE_INT parm_align
2936 ? MAX (DECL_ALIGN (parm
), BITS_PER_WORD
) : DECL_ALIGN (parm
));
2938 SET_DECL_ALIGN (parm
, parm_align
);
2939 if (DECL_ALIGN (parm
) > MAX_SUPPORTED_STACK_ALIGNMENT
)
2941 rtx allocsize
= gen_int_mode (size_stored
, Pmode
);
2942 get_dynamic_stack_size (&allocsize
, 0, DECL_ALIGN (parm
), NULL
);
2943 stack_parm
= assign_stack_local (BLKmode
, UINTVAL (allocsize
),
2944 MAX_SUPPORTED_STACK_ALIGNMENT
);
2945 rtx addr
= align_dynamic_address (XEXP (stack_parm
, 0),
2947 mark_reg_pointer (addr
, DECL_ALIGN (parm
));
2948 stack_parm
= gen_rtx_MEM (GET_MODE (stack_parm
), addr
);
2949 MEM_NOTRAP_P (stack_parm
) = 1;
2952 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2954 if (known_eq (GET_MODE_SIZE (GET_MODE (entry_parm
)), size
))
2955 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2956 set_mem_attributes (stack_parm
, parm
, 1);
2959 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2960 calls that pass values in multiple non-contiguous locations. */
2961 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2965 /* Note that we will be storing an integral number of words.
2966 So we have to be careful to ensure that we allocate an
2967 integral number of words. We do this above when we call
2968 assign_stack_local if space was not allocated in the argument
2969 list. If it was, this will not work if PARM_BOUNDARY is not
2970 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2971 if it becomes a problem. Exception is when BLKmode arrives
2972 with arguments not conforming to word_mode. */
2974 if (data
->stack_parm
== 0)
2976 else if (GET_CODE (entry_parm
) == PARALLEL
)
2979 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2981 mem
= validize_mem (copy_rtx (stack_parm
));
2983 /* Handle values in multiple non-contiguous locations. */
2984 if (GET_CODE (entry_parm
) == PARALLEL
&& !MEM_P (mem
))
2985 emit_group_store (mem
, entry_parm
, data
->arg
.type
, size
);
2986 else if (GET_CODE (entry_parm
) == PARALLEL
)
2988 push_to_sequence2 (all
->first_conversion_insn
,
2989 all
->last_conversion_insn
);
2990 emit_group_store (mem
, entry_parm
, data
->arg
.type
, size
);
2991 all
->first_conversion_insn
= get_insns ();
2992 all
->last_conversion_insn
= get_last_insn ();
2994 in_conversion_seq
= true;
3000 /* If SIZE is that of a mode no bigger than a word, just use
3001 that mode's store operation. */
3002 else if (size
<= UNITS_PER_WORD
)
3004 unsigned int bits
= size
* BITS_PER_UNIT
;
3005 machine_mode mode
= int_mode_for_size (bits
, 0).else_blk ();
3008 #ifdef BLOCK_REG_PADDING
3009 && (size
== UNITS_PER_WORD
3010 || (BLOCK_REG_PADDING (mode
, data
->arg
.type
, 1)
3011 != (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
3017 /* We are really truncating a word_mode value containing
3018 SIZE bytes into a value of mode MODE. If such an
3019 operation requires no actual instructions, we can refer
3020 to the value directly in mode MODE, otherwise we must
3021 start with the register in word_mode and explicitly
3023 if (mode
== word_mode
3024 || TRULY_NOOP_TRUNCATION_MODES_P (mode
, word_mode
))
3025 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
3028 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3029 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
3031 emit_move_insn (change_address (mem
, mode
, 0), reg
);
3034 #ifdef BLOCK_REG_PADDING
3035 /* Storing the register in memory as a full word, as
3036 move_block_from_reg below would do, and then using the
3037 MEM in a smaller mode, has the effect of shifting right
3038 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3039 shifting must be explicit. */
3040 else if (!MEM_P (mem
))
3044 /* If the assert below fails, we should have taken the
3045 mode != BLKmode path above, unless we have downward
3046 padding of smaller-than-word arguments on a machine
3047 with little-endian bytes, which would likely require
3048 additional changes to work correctly. */
3049 gcc_checking_assert (BYTES_BIG_ENDIAN
3050 && (BLOCK_REG_PADDING (mode
,
3054 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3056 x
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3057 x
= expand_shift (RSHIFT_EXPR
, word_mode
, x
, by
,
3059 x
= force_reg (word_mode
, x
);
3060 x
= gen_lowpart_SUBREG (GET_MODE (mem
), x
);
3062 emit_move_insn (mem
, x
);
3066 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3067 machine must be aligned to the left before storing
3068 to memory. Note that the previous test doesn't
3069 handle all cases (e.g. SIZE == 3). */
3070 else if (size
!= UNITS_PER_WORD
3071 #ifdef BLOCK_REG_PADDING
3072 && (BLOCK_REG_PADDING (mode
, data
->arg
.type
, 1)
3080 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3081 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3083 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, by
, NULL_RTX
, 1);
3084 tem
= change_address (mem
, word_mode
, 0);
3085 emit_move_insn (tem
, x
);
3088 move_block_from_reg (REGNO (entry_parm
), mem
,
3089 size_stored
/ UNITS_PER_WORD
);
3091 else if (!MEM_P (mem
))
3093 gcc_checking_assert (size
> UNITS_PER_WORD
);
3094 #ifdef BLOCK_REG_PADDING
3095 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem
),
3099 emit_move_insn (mem
, entry_parm
);
3102 move_block_from_reg (REGNO (entry_parm
), mem
,
3103 size_stored
/ UNITS_PER_WORD
);
3105 else if (data
->stack_parm
== 0 && !TYPE_EMPTY_P (data
->arg
.type
))
3107 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3108 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
3110 all
->first_conversion_insn
= get_insns ();
3111 all
->last_conversion_insn
= get_last_insn ();
3113 in_conversion_seq
= true;
3118 if (!in_conversion_seq
)
3119 emit_move_insn (target_reg
, stack_parm
);
3122 push_to_sequence2 (all
->first_conversion_insn
,
3123 all
->last_conversion_insn
);
3124 emit_move_insn (target_reg
, stack_parm
);
3125 all
->first_conversion_insn
= get_insns ();
3126 all
->last_conversion_insn
= get_last_insn ();
3129 stack_parm
= target_reg
;
3132 data
->stack_parm
= stack_parm
;
3133 set_parm_rtl (parm
, stack_parm
);
3136 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3137 parameter. Get it there. Perform all ABI specified conversions. */
3140 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
3141 struct assign_parm_data_one
*data
)
3143 rtx parmreg
, validated_mem
;
3144 rtx equiv_stack_parm
;
3145 machine_mode promoted_nominal_mode
;
3146 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3147 bool did_conversion
= false;
3148 bool need_conversion
, moved
;
3149 enum insn_code icode
;
3152 /* Store the parm in a pseudoregister during the function, but we may
3153 need to do it in a wider mode. Using 2 here makes the result
3154 consistent with promote_decl_mode and thus expand_expr_real_1. */
3155 promoted_nominal_mode
3156 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
3157 TREE_TYPE (current_function_decl
), 2);
3159 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
3160 if (!DECL_ARTIFICIAL (parm
))
3161 mark_user_reg (parmreg
);
3163 /* If this was an item that we received a pointer to,
3164 set rtl appropriately. */
3165 if (data
->arg
.pass_by_reference
)
3167 rtl
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->arg
.type
)), parmreg
);
3168 set_mem_attributes (rtl
, parm
, 1);
3173 assign_parm_remove_parallels (data
);
3175 /* Copy the value into the register, thus bridging between
3176 assign_parm_find_data_types and expand_expr_real_1. */
3178 equiv_stack_parm
= data
->stack_parm
;
3179 validated_mem
= validize_mem (copy_rtx (data
->entry_parm
));
3181 need_conversion
= (data
->nominal_mode
!= data
->passed_mode
3182 || promoted_nominal_mode
!= data
->arg
.mode
);
3186 && GET_MODE_CLASS (data
->nominal_mode
) == MODE_INT
3187 && data
->nominal_mode
== data
->passed_mode
3188 && data
->nominal_mode
== GET_MODE (data
->entry_parm
))
3190 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3191 mode, by the caller. We now have to convert it to
3192 NOMINAL_MODE, if different. However, PARMREG may be in
3193 a different mode than NOMINAL_MODE if it is being stored
3196 If ENTRY_PARM is a hard register, it might be in a register
3197 not valid for operating in its mode (e.g., an odd-numbered
3198 register for a DFmode). In that case, moves are the only
3199 thing valid, so we can't do a convert from there. This
3200 occurs when the calling sequence allow such misaligned
3203 In addition, the conversion may involve a call, which could
3204 clobber parameters which haven't been copied to pseudo
3207 First, we try to emit an insn which performs the necessary
3208 conversion. We verify that this insn does not clobber any
3213 icode
= can_extend_p (promoted_nominal_mode
, data
->passed_mode
,
3217 op1
= validated_mem
;
3218 if (icode
!= CODE_FOR_nothing
3219 && insn_operand_matches (icode
, 0, op0
)
3220 && insn_operand_matches (icode
, 1, op1
))
3222 enum rtx_code code
= unsignedp
? ZERO_EXTEND
: SIGN_EXTEND
;
3223 rtx_insn
*insn
, *insns
;
3225 HARD_REG_SET hardregs
;
3228 /* If op1 is a hard register that is likely spilled, first
3229 force it into a pseudo, otherwise combiner might extend
3230 its lifetime too much. */
3231 if (GET_CODE (t
) == SUBREG
)
3234 && HARD_REGISTER_P (t
)
3235 && ! TEST_HARD_REG_BIT (fixed_reg_set
, REGNO (t
))
3236 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t
))))
3238 t
= gen_reg_rtx (GET_MODE (op1
));
3239 emit_move_insn (t
, op1
);
3243 rtx_insn
*pat
= gen_extend_insn (op0
, t
, promoted_nominal_mode
,
3244 data
->passed_mode
, unsignedp
);
3246 insns
= get_insns ();
3249 CLEAR_HARD_REG_SET (hardregs
);
3250 for (insn
= insns
; insn
&& moved
; insn
= NEXT_INSN (insn
))
3253 note_stores (insn
, record_hard_reg_sets
, &hardregs
);
3254 if (!hard_reg_set_empty_p (hardregs
))
3263 if (equiv_stack_parm
!= NULL_RTX
)
3264 equiv_stack_parm
= gen_rtx_fmt_e (code
, GET_MODE (parmreg
),
3271 /* Nothing to do. */
3273 else if (need_conversion
)
3275 /* We did not have an insn to convert directly, or the sequence
3276 generated appeared unsafe. We must first copy the parm to a
3277 pseudo reg, and save the conversion until after all
3278 parameters have been moved. */
3281 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3283 emit_move_insn (tempreg
, validated_mem
);
3285 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3286 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
3288 if (partial_subreg_p (tempreg
)
3289 && GET_MODE (tempreg
) == data
->nominal_mode
3290 && REG_P (SUBREG_REG (tempreg
))
3291 && data
->nominal_mode
== data
->passed_mode
3292 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
))
3294 /* The argument is already sign/zero extended, so note it
3296 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
3297 SUBREG_PROMOTED_SET (tempreg
, unsignedp
);
3300 /* TREE_USED gets set erroneously during expand_assignment. */
3301 save_tree_used
= TREE_USED (parm
);
3302 SET_DECL_RTL (parm
, rtl
);
3303 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
3304 SET_DECL_RTL (parm
, NULL_RTX
);
3305 TREE_USED (parm
) = save_tree_used
;
3306 all
->first_conversion_insn
= get_insns ();
3307 all
->last_conversion_insn
= get_last_insn ();
3310 did_conversion
= true;
3312 else if (MEM_P (data
->entry_parm
)
3313 && GET_MODE_ALIGNMENT (promoted_nominal_mode
)
3314 > MEM_ALIGN (data
->entry_parm
)
3315 && (((icode
= optab_handler (movmisalign_optab
,
3316 promoted_nominal_mode
))
3317 != CODE_FOR_nothing
)
3318 || targetm
.slow_unaligned_access (promoted_nominal_mode
,
3319 MEM_ALIGN (data
->entry_parm
))))
3321 if (icode
!= CODE_FOR_nothing
)
3322 emit_insn (GEN_FCN (icode
) (parmreg
, validated_mem
));
3324 rtl
= parmreg
= extract_bit_field (validated_mem
,
3325 GET_MODE_BITSIZE (promoted_nominal_mode
), 0,
3327 promoted_nominal_mode
, VOIDmode
, false, NULL
);
3330 emit_move_insn (parmreg
, validated_mem
);
3332 /* If we were passed a pointer but the actual value can live in a register,
3333 retrieve it and use it directly. Note that we cannot use nominal_mode,
3334 because it will have been set to Pmode above, we must use the actual mode
3335 of the parameter instead. */
3336 if (data
->arg
.pass_by_reference
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
)
3338 /* Use a stack slot for debugging purposes if possible. */
3339 if (use_register_for_decl (parm
))
3341 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
3342 mark_user_reg (parmreg
);
3346 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3347 TYPE_MODE (TREE_TYPE (parm
)),
3348 TYPE_ALIGN (TREE_TYPE (parm
)));
3350 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm
)),
3351 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm
))),
3353 set_mem_attributes (parmreg
, parm
, 1);
3356 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3357 the debug info in case it is not legitimate. */
3358 if (GET_MODE (parmreg
) != GET_MODE (rtl
))
3360 rtx tempreg
= gen_reg_rtx (GET_MODE (rtl
));
3361 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3363 push_to_sequence2 (all
->first_conversion_insn
,
3364 all
->last_conversion_insn
);
3365 emit_move_insn (tempreg
, rtl
);
3366 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
3367 emit_move_insn (MEM_P (parmreg
) ? copy_rtx (parmreg
) : parmreg
,
3369 all
->first_conversion_insn
= get_insns ();
3370 all
->last_conversion_insn
= get_last_insn ();
3373 did_conversion
= true;
3376 emit_move_insn (MEM_P (parmreg
) ? copy_rtx (parmreg
) : parmreg
, rtl
);
3380 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3382 data
->stack_parm
= NULL
;
3385 set_parm_rtl (parm
, rtl
);
3387 /* Mark the register as eliminable if we did no conversion and it was
3388 copied from memory at a fixed offset, and the arg pointer was not
3389 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3390 offset formed an invalid address, such memory-equivalences as we
3391 make here would screw up life analysis for it. */
3392 if (data
->nominal_mode
== data
->passed_mode
3394 && data
->stack_parm
!= 0
3395 && MEM_P (data
->stack_parm
)
3396 && data
->locate
.offset
.var
== 0
3397 && reg_mentioned_p (virtual_incoming_args_rtx
,
3398 XEXP (data
->stack_parm
, 0)))
3400 rtx_insn
*linsn
= get_last_insn ();
3404 /* Mark complex types separately. */
3405 if (GET_CODE (parmreg
) == CONCAT
)
3407 scalar_mode submode
= GET_MODE_INNER (GET_MODE (parmreg
));
3408 int regnor
= REGNO (XEXP (parmreg
, 0));
3409 int regnoi
= REGNO (XEXP (parmreg
, 1));
3410 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
3411 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
3412 GET_MODE_SIZE (submode
));
3414 /* Scan backwards for the set of the real and
3416 for (sinsn
= linsn
; sinsn
!= 0;
3417 sinsn
= prev_nonnote_insn (sinsn
))
3419 set
= single_set (sinsn
);
3423 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
3424 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
3425 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
3426 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
3430 set_dst_reg_note (linsn
, REG_EQUIV
, equiv_stack_parm
, parmreg
);
3433 /* For pointer data type, suggest pointer register. */
3434 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
3435 mark_reg_pointer (parmreg
,
3436 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
3439 /* A subroutine of assign_parms. Allocate stack space to hold the current
3440 parameter. Get it there. Perform all ABI specified conversions. */
3443 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
3444 struct assign_parm_data_one
*data
)
3446 /* Value must be stored in the stack slot STACK_PARM during function
3448 bool to_conversion
= false;
3450 assign_parm_remove_parallels (data
);
3452 if (data
->arg
.mode
!= data
->nominal_mode
)
3454 /* Conversion is required. */
3455 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3457 emit_move_insn (tempreg
, validize_mem (copy_rtx (data
->entry_parm
)));
3459 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3460 to_conversion
= true;
3462 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
3463 TYPE_UNSIGNED (TREE_TYPE (parm
)));
3465 if (data
->stack_parm
)
3468 = subreg_lowpart_offset (data
->nominal_mode
,
3469 GET_MODE (data
->stack_parm
));
3470 /* ??? This may need a big-endian conversion on sparc64. */
3472 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
3473 if (maybe_ne (offset
, 0) && MEM_OFFSET_KNOWN_P (data
->stack_parm
))
3474 set_mem_offset (data
->stack_parm
,
3475 MEM_OFFSET (data
->stack_parm
) + offset
);
3479 if (data
->entry_parm
!= data
->stack_parm
)
3483 if (data
->stack_parm
== 0)
3485 int align
= STACK_SLOT_ALIGNMENT (data
->arg
.type
,
3486 GET_MODE (data
->entry_parm
),
3487 TYPE_ALIGN (data
->arg
.type
));
3488 if (align
< (int)GET_MODE_ALIGNMENT (GET_MODE (data
->entry_parm
))
3489 && ((optab_handler (movmisalign_optab
,
3490 GET_MODE (data
->entry_parm
))
3491 != CODE_FOR_nothing
)
3492 || targetm
.slow_unaligned_access (GET_MODE (data
->entry_parm
),
3494 align
= GET_MODE_ALIGNMENT (GET_MODE (data
->entry_parm
));
3496 = assign_stack_local (GET_MODE (data
->entry_parm
),
3497 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3499 align
= MEM_ALIGN (data
->stack_parm
);
3500 set_mem_attributes (data
->stack_parm
, parm
, 1);
3501 set_mem_align (data
->stack_parm
, align
);
3504 dest
= validize_mem (copy_rtx (data
->stack_parm
));
3505 src
= validize_mem (copy_rtx (data
->entry_parm
));
3507 if (TYPE_EMPTY_P (data
->arg
.type
))
3508 /* Empty types don't really need to be copied. */;
3509 else if (MEM_P (src
))
3511 /* Use a block move to handle potentially misaligned entry_parm. */
3513 push_to_sequence2 (all
->first_conversion_insn
,
3514 all
->last_conversion_insn
);
3515 to_conversion
= true;
3517 emit_block_move (dest
, src
,
3518 GEN_INT (int_size_in_bytes (data
->arg
.type
)),
3524 src
= force_reg (GET_MODE (src
), src
);
3525 emit_move_insn (dest
, src
);
3531 all
->first_conversion_insn
= get_insns ();
3532 all
->last_conversion_insn
= get_last_insn ();
3536 set_parm_rtl (parm
, data
->stack_parm
);
3539 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3540 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3543 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
,
3547 tree orig_fnargs
= all
->orig_fnargs
;
3550 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
), ++i
)
3552 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3553 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3555 rtx tmp
, real
, imag
;
3556 scalar_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3558 real
= DECL_RTL (fnargs
[i
]);
3559 imag
= DECL_RTL (fnargs
[i
+ 1]);
3560 if (inner
!= GET_MODE (real
))
3562 real
= gen_lowpart_SUBREG (inner
, real
);
3563 imag
= gen_lowpart_SUBREG (inner
, imag
);
3566 if (TREE_ADDRESSABLE (parm
))
3569 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3570 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3572 TYPE_ALIGN (TREE_TYPE (parm
)));
3574 /* split_complex_arg put the real and imag parts in
3575 pseudos. Move them to memory. */
3576 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3577 set_mem_attributes (tmp
, parm
, 1);
3578 rmem
= adjust_address_nv (tmp
, inner
, 0);
3579 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3580 push_to_sequence2 (all
->first_conversion_insn
,
3581 all
->last_conversion_insn
);
3582 emit_move_insn (rmem
, real
);
3583 emit_move_insn (imem
, imag
);
3584 all
->first_conversion_insn
= get_insns ();
3585 all
->last_conversion_insn
= get_last_insn ();
3589 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3590 set_parm_rtl (parm
, tmp
);
3592 real
= DECL_INCOMING_RTL (fnargs
[i
]);
3593 imag
= DECL_INCOMING_RTL (fnargs
[i
+ 1]);
3594 if (inner
!= GET_MODE (real
))
3596 real
= gen_lowpart_SUBREG (inner
, real
);
3597 imag
= gen_lowpart_SUBREG (inner
, imag
);
3599 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3600 set_decl_incoming_rtl (parm
, tmp
, false);
3606 /* Assign RTL expressions to the function's parameters. This may involve
3607 copying them into registers and using those registers as the DECL_RTL. */
3610 assign_parms (tree fndecl
)
3612 struct assign_parm_data_all all
;
3617 crtl
->args
.internal_arg_pointer
3618 = targetm
.calls
.internal_arg_pointer ();
3620 assign_parms_initialize_all (&all
);
3621 fnargs
= assign_parms_augmented_arg_list (&all
);
3623 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3625 struct assign_parm_data_one data
;
3627 /* Extract the type of PARM; adjust it according to ABI. */
3628 assign_parm_find_data_types (&all
, parm
, &data
);
3630 /* Early out for errors and void parameters. */
3631 if (data
.passed_mode
== VOIDmode
)
3633 SET_DECL_RTL (parm
, const0_rtx
);
3634 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3638 /* Estimate stack alignment from parameter alignment. */
3639 if (SUPPORTS_STACK_ALIGNMENT
)
3642 = targetm
.calls
.function_arg_boundary (data
.arg
.mode
,
3644 align
= MINIMUM_ALIGNMENT (data
.arg
.type
, data
.arg
.mode
, align
);
3645 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3646 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3647 TYPE_MODE (data
.nominal_type
),
3648 TYPE_ALIGN (data
.nominal_type
));
3649 if (crtl
->stack_alignment_estimated
< align
)
3651 gcc_assert (!crtl
->stack_realign_processed
);
3652 crtl
->stack_alignment_estimated
= align
;
3656 /* Find out where the parameter arrives in this function. */
3657 assign_parm_find_entry_rtl (&all
, &data
);
3659 /* Find out where stack space for this parameter might be. */
3660 if (assign_parm_is_stack_parm (&all
, &data
))
3662 assign_parm_find_stack_rtl (parm
, &data
);
3663 assign_parm_adjust_entry_rtl (&data
);
3664 /* For arguments that occupy no space in the parameter
3665 passing area, have non-zero size and have address taken,
3666 force creation of a stack slot so that they have distinct
3667 address from other parameters. */
3668 if (TYPE_EMPTY_P (data
.arg
.type
)
3669 && TREE_ADDRESSABLE (parm
)
3670 && data
.entry_parm
== data
.stack_parm
3671 && MEM_P (data
.entry_parm
)
3672 && int_size_in_bytes (data
.arg
.type
))
3673 data
.stack_parm
= NULL_RTX
;
3675 /* Record permanently how this parm was passed. */
3676 if (data
.arg
.pass_by_reference
)
3679 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
.arg
.type
)),
3681 set_decl_incoming_rtl (parm
, incoming_rtl
, true);
3684 set_decl_incoming_rtl (parm
, data
.entry_parm
, false);
3686 assign_parm_adjust_stack_rtl (&data
);
3688 if (assign_parm_setup_block_p (&data
))
3689 assign_parm_setup_block (&all
, parm
, &data
);
3690 else if (data
.arg
.pass_by_reference
|| use_register_for_decl (parm
))
3691 assign_parm_setup_reg (&all
, parm
, &data
);
3693 assign_parm_setup_stack (&all
, parm
, &data
);
3695 if (cfun
->stdarg
&& !DECL_CHAIN (parm
))
3696 assign_parms_setup_varargs (&all
, &data
, false);
3698 /* Update info on where next arg arrives in registers. */
3699 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.arg
);
3702 if (targetm
.calls
.split_complex_arg
)
3703 assign_parms_unsplit_complex (&all
, fnargs
);
3707 /* Output all parameter conversion instructions (possibly including calls)
3708 now that all parameters have been copied out of hard registers. */
3709 emit_insn (all
.first_conversion_insn
);
3711 /* Estimate reload stack alignment from scalar return mode. */
3712 if (SUPPORTS_STACK_ALIGNMENT
)
3714 if (DECL_RESULT (fndecl
))
3716 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3717 machine_mode mode
= TYPE_MODE (type
);
3721 && !AGGREGATE_TYPE_P (type
))
3723 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3724 if (crtl
->stack_alignment_estimated
< align
)
3726 gcc_assert (!crtl
->stack_realign_processed
);
3727 crtl
->stack_alignment_estimated
= align
;
3733 /* If we are receiving a struct value address as the first argument, set up
3734 the RTL for the function result. As this might require code to convert
3735 the transmitted address to Pmode, we do this here to ensure that possible
3736 preliminary conversions of the address have been emitted already. */
3737 if (all
.function_result_decl
)
3739 tree result
= DECL_RESULT (current_function_decl
);
3740 rtx addr
= DECL_RTL (all
.function_result_decl
);
3743 if (DECL_BY_REFERENCE (result
))
3745 SET_DECL_VALUE_EXPR (result
, all
.function_result_decl
);
3750 SET_DECL_VALUE_EXPR (result
,
3751 build1 (INDIRECT_REF
, TREE_TYPE (result
),
3752 all
.function_result_decl
));
3753 addr
= convert_memory_address (Pmode
, addr
);
3754 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3755 set_mem_attributes (x
, result
, 1);
3758 DECL_HAS_VALUE_EXPR_P (result
) = 1;
3760 set_parm_rtl (result
, x
);
3763 /* We have aligned all the args, so add space for the pretend args. */
3764 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3765 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3766 crtl
->args
.size
= all
.stack_args_size
.constant
;
3768 /* Adjust function incoming argument size for alignment and
3771 crtl
->args
.size
= upper_bound (crtl
->args
.size
, all
.reg_parm_stack_space
);
3772 crtl
->args
.size
= aligned_upper_bound (crtl
->args
.size
,
3773 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3775 if (ARGS_GROW_DOWNWARD
)
3777 crtl
->args
.arg_offset_rtx
3778 = (all
.stack_args_size
.var
== 0
3779 ? gen_int_mode (-all
.stack_args_size
.constant
, Pmode
)
3780 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3781 size_int (-all
.stack_args_size
.constant
)),
3782 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3785 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3787 /* See how many bytes, if any, of its args a function should try to pop
3790 crtl
->args
.pops_args
= targetm
.calls
.return_pops_args (fndecl
,
3794 /* For stdarg.h function, save info about
3795 regs and stack space used by the named args. */
3797 crtl
->args
.info
= all
.args_so_far_v
;
3799 /* Set the rtx used for the function return value. Put this in its
3800 own variable so any optimizers that need this information don't have
3801 to include tree.h. Do this here so it gets done when an inlined
3802 function gets output. */
3805 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3806 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3808 /* If scalar return value was computed in a pseudo-reg, or was a named
3809 return value that got dumped to the stack, copy that to the hard
3811 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3813 tree decl_result
= DECL_RESULT (fndecl
);
3814 rtx decl_rtl
= DECL_RTL (decl_result
);
3816 if (REG_P (decl_rtl
)
3817 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3818 : DECL_REGISTER (decl_result
))
3822 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3824 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3825 /* The delay slot scheduler assumes that crtl->return_rtx
3826 holds the hard register containing the return value, not a
3827 temporary pseudo. */
3828 crtl
->return_rtx
= real_decl_rtl
;
3833 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3834 For all seen types, gimplify their sizes. */
3837 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3844 if (POINTER_TYPE_P (t
))
3846 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3847 && !TYPE_SIZES_GIMPLIFIED (t
))
3849 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3857 /* Gimplify the parameter list for current_function_decl. This involves
3858 evaluating SAVE_EXPRs of variable sized parameters and generating code
3859 to implement callee-copies reference parameters. Returns a sequence of
3860 statements to add to the beginning of the function. */
3863 gimplify_parameters (gimple_seq
*cleanup
)
3865 struct assign_parm_data_all all
;
3867 gimple_seq stmts
= NULL
;
3871 assign_parms_initialize_all (&all
);
3872 fnargs
= assign_parms_augmented_arg_list (&all
);
3874 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3876 struct assign_parm_data_one data
;
3878 /* Extract the type of PARM; adjust it according to ABI. */
3879 assign_parm_find_data_types (&all
, parm
, &data
);
3881 /* Early out for errors and void parameters. */
3882 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3885 /* Update info on where next arg arrives in registers. */
3886 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.arg
);
3888 /* ??? Once upon a time variable_size stuffed parameter list
3889 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3890 turned out to be less than manageable in the gimple world.
3891 Now we have to hunt them down ourselves. */
3892 walk_tree_without_duplicates (&data
.arg
.type
,
3893 gimplify_parm_type
, &stmts
);
3895 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3897 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3898 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3901 if (data
.arg
.pass_by_reference
)
3903 tree type
= TREE_TYPE (data
.arg
.type
);
3904 function_arg_info
orig_arg (type
, data
.arg
.named
);
3905 if (reference_callee_copied (&all
.args_so_far_v
, orig_arg
))
3909 /* For constant-sized objects, this is trivial; for
3910 variable-sized objects, we have to play games. */
3911 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3912 && !(flag_stack_check
== GENERIC_STACK_CHECK
3913 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3914 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3916 local
= create_tmp_var (type
, get_name (parm
));
3917 DECL_IGNORED_P (local
) = 0;
3918 /* If PARM was addressable, move that flag over
3919 to the local copy, as its address will be taken,
3920 not the PARMs. Keep the parms address taken
3921 as we'll query that flag during gimplification. */
3922 if (TREE_ADDRESSABLE (parm
))
3923 TREE_ADDRESSABLE (local
) = 1;
3924 if (DECL_NOT_GIMPLE_REG_P (parm
))
3925 DECL_NOT_GIMPLE_REG_P (local
) = 1;
3927 if (!is_gimple_reg (local
)
3928 && flag_stack_reuse
!= SR_NONE
)
3930 tree clobber
= build_clobber (type
);
3931 gimple
*clobber_stmt
;
3932 clobber_stmt
= gimple_build_assign (local
, clobber
);
3933 gimple_seq_add_stmt (cleanup
, clobber_stmt
);
3938 tree ptr_type
, addr
;
3940 ptr_type
= build_pointer_type (type
);
3941 addr
= create_tmp_reg (ptr_type
, get_name (parm
));
3942 DECL_IGNORED_P (addr
) = 0;
3943 local
= build_fold_indirect_ref (addr
);
3945 t
= build_alloca_call_expr (DECL_SIZE_UNIT (parm
),
3947 max_int_size_in_bytes (type
));
3948 /* The call has been built for a variable-sized object. */
3949 CALL_ALLOCA_FOR_VAR_P (t
) = 1;
3950 t
= fold_convert (ptr_type
, t
);
3951 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3952 gimplify_and_add (t
, &stmts
);
3955 gimplify_assign (local
, parm
, &stmts
);
3957 SET_DECL_VALUE_EXPR (parm
, local
);
3958 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3968 /* Compute the size and offset from the start of the stacked arguments for a
3969 parm passed in mode PASSED_MODE and with type TYPE.
3971 INITIAL_OFFSET_PTR points to the current offset into the stacked
3974 The starting offset and size for this parm are returned in
3975 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3976 nonzero, the offset is that of stack slot, which is returned in
3977 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3978 padding required from the initial offset ptr to the stack slot.
3980 IN_REGS is nonzero if the argument will be passed in registers. It will
3981 never be set if REG_PARM_STACK_SPACE is not defined.
3983 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3984 for arguments which are passed in registers.
3986 FNDECL is the function in which the argument was defined.
3988 There are two types of rounding that are done. The first, controlled by
3989 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3990 argument list to be aligned to the specific boundary (in bits). This
3991 rounding affects the initial and starting offsets, but not the argument
3994 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3995 optionally rounds the size of the parm to PARM_BOUNDARY. The
3996 initial offset is not affected by this rounding, while the size always
3997 is and the starting offset may be. */
3999 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
4000 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
4001 callers pass in the total size of args so far as
4002 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
4005 locate_and_pad_parm (machine_mode passed_mode
, tree type
, int in_regs
,
4006 int reg_parm_stack_space
, int partial
,
4007 tree fndecl ATTRIBUTE_UNUSED
,
4008 struct args_size
*initial_offset_ptr
,
4009 struct locate_and_pad_arg_data
*locate
)
4012 pad_direction where_pad
;
4013 unsigned int boundary
, round_boundary
;
4014 int part_size_in_regs
;
4016 /* If we have found a stack parm before we reach the end of the
4017 area reserved for registers, skip that area. */
4020 if (reg_parm_stack_space
> 0)
4022 if (initial_offset_ptr
->var
4023 || !ordered_p (initial_offset_ptr
->constant
,
4024 reg_parm_stack_space
))
4026 initial_offset_ptr
->var
4027 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
4028 ssize_int (reg_parm_stack_space
));
4029 initial_offset_ptr
->constant
= 0;
4032 initial_offset_ptr
->constant
4033 = ordered_max (initial_offset_ptr
->constant
,
4034 reg_parm_stack_space
);
4038 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
4041 ? arg_size_in_bytes (type
)
4042 : size_int (GET_MODE_SIZE (passed_mode
)));
4043 where_pad
= targetm
.calls
.function_arg_padding (passed_mode
, type
);
4044 boundary
= targetm
.calls
.function_arg_boundary (passed_mode
, type
);
4045 round_boundary
= targetm
.calls
.function_arg_round_boundary (passed_mode
,
4047 locate
->where_pad
= where_pad
;
4049 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4050 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
4051 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
4053 locate
->boundary
= boundary
;
4055 if (SUPPORTS_STACK_ALIGNMENT
)
4057 /* stack_alignment_estimated can't change after stack has been
4059 if (crtl
->stack_alignment_estimated
< boundary
)
4061 if (!crtl
->stack_realign_processed
)
4062 crtl
->stack_alignment_estimated
= boundary
;
4065 /* If stack is realigned and stack alignment value
4066 hasn't been finalized, it is OK not to increase
4067 stack_alignment_estimated. The bigger alignment
4068 requirement is recorded in stack_alignment_needed
4070 gcc_assert (!crtl
->stack_realign_finalized
4071 && crtl
->stack_realign_needed
);
4076 if (ARGS_GROW_DOWNWARD
)
4078 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
4079 if (initial_offset_ptr
->var
)
4080 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
4081 initial_offset_ptr
->var
);
4085 if (where_pad
!= PAD_NONE
4086 && (!tree_fits_uhwi_p (sizetree
)
4087 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
4088 s2
= round_up (s2
, round_boundary
/ BITS_PER_UNIT
);
4089 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
4092 locate
->slot_offset
.constant
+= part_size_in_regs
;
4094 if (!in_regs
|| reg_parm_stack_space
> 0)
4095 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
4096 &locate
->alignment_pad
);
4098 locate
->size
.constant
= (-initial_offset_ptr
->constant
4099 - locate
->slot_offset
.constant
);
4100 if (initial_offset_ptr
->var
)
4101 locate
->size
.var
= size_binop (MINUS_EXPR
,
4102 size_binop (MINUS_EXPR
,
4104 initial_offset_ptr
->var
),
4105 locate
->slot_offset
.var
);
4107 /* Pad_below needs the pre-rounded size to know how much to pad
4109 locate
->offset
= locate
->slot_offset
;
4110 if (where_pad
== PAD_DOWNWARD
)
4111 pad_below (&locate
->offset
, passed_mode
, sizetree
);
4116 if (!in_regs
|| reg_parm_stack_space
> 0)
4117 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
4118 &locate
->alignment_pad
);
4119 locate
->slot_offset
= *initial_offset_ptr
;
4121 #ifdef PUSH_ROUNDING
4122 if (passed_mode
!= BLKmode
)
4123 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
4126 /* Pad_below needs the pre-rounded size to know how much to pad below
4127 so this must be done before rounding up. */
4128 locate
->offset
= locate
->slot_offset
;
4129 if (where_pad
== PAD_DOWNWARD
)
4130 pad_below (&locate
->offset
, passed_mode
, sizetree
);
4132 if (where_pad
!= PAD_NONE
4133 && (!tree_fits_uhwi_p (sizetree
)
4134 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
4135 sizetree
= round_up (sizetree
, round_boundary
/ BITS_PER_UNIT
);
4137 ADD_PARM_SIZE (locate
->size
, sizetree
);
4139 locate
->size
.constant
-= part_size_in_regs
;
4142 locate
->offset
.constant
4143 += targetm
.calls
.function_arg_offset (passed_mode
, type
);
4146 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4147 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4150 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
4151 struct args_size
*alignment_pad
)
4153 tree save_var
= NULL_TREE
;
4154 poly_int64 save_constant
= 0;
4155 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
4156 poly_int64 sp_offset
= STACK_POINTER_OFFSET
;
4158 #ifdef SPARC_STACK_BOUNDARY_HACK
4159 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4160 the real alignment of %sp. However, when it does this, the
4161 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4162 if (SPARC_STACK_BOUNDARY_HACK
)
4166 if (boundary
> PARM_BOUNDARY
)
4168 save_var
= offset_ptr
->var
;
4169 save_constant
= offset_ptr
->constant
;
4172 alignment_pad
->var
= NULL_TREE
;
4173 alignment_pad
->constant
= 0;
4175 if (boundary
> BITS_PER_UNIT
)
4179 || !known_misalignment (offset_ptr
->constant
+ sp_offset
,
4180 boundary_in_bytes
, &misalign
))
4182 tree sp_offset_tree
= ssize_int (sp_offset
);
4183 tree offset
= size_binop (PLUS_EXPR
,
4184 ARGS_SIZE_TREE (*offset_ptr
),
4187 if (ARGS_GROW_DOWNWARD
)
4188 rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
4190 rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
4192 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
4193 /* ARGS_SIZE_TREE includes constant term. */
4194 offset_ptr
->constant
= 0;
4195 if (boundary
> PARM_BOUNDARY
)
4196 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
4201 if (ARGS_GROW_DOWNWARD
)
4202 offset_ptr
->constant
-= misalign
;
4204 offset_ptr
->constant
+= -misalign
& (boundary_in_bytes
- 1);
4206 if (boundary
> PARM_BOUNDARY
)
4207 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
4213 pad_below (struct args_size
*offset_ptr
, machine_mode passed_mode
, tree sizetree
)
4215 unsigned int align
= PARM_BOUNDARY
/ BITS_PER_UNIT
;
4217 if (passed_mode
!= BLKmode
4218 && known_misalignment (GET_MODE_SIZE (passed_mode
), align
, &misalign
))
4219 offset_ptr
->constant
+= -misalign
& (align
- 1);
4222 if (TREE_CODE (sizetree
) != INTEGER_CST
4223 || (TREE_INT_CST_LOW (sizetree
) & (align
- 1)) != 0)
4225 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4226 tree s2
= round_up (sizetree
, align
);
4228 ADD_PARM_SIZE (*offset_ptr
, s2
);
4229 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4235 /* True if register REGNO was alive at a place where `setjmp' was
4236 called and was set more than once or is an argument. Such regs may
4237 be clobbered by `longjmp'. */
4240 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
4242 /* There appear to be cases where some local vars never reach the
4243 backend but have bogus regnos. */
4244 if (regno
>= max_reg_num ())
4247 return ((REG_N_SETS (regno
) > 1
4248 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun
)),
4250 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
4253 /* Walk the tree of blocks describing the binding levels within a
4254 function and warn about variables the might be killed by setjmp or
4255 vfork. This is done after calling flow_analysis before register
4256 allocation since that will clobber the pseudo-regs to hard
4260 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
4264 for (decl
= BLOCK_VARS (block
); decl
; decl
= DECL_CHAIN (decl
))
4267 && DECL_RTL_SET_P (decl
)
4268 && REG_P (DECL_RTL (decl
))
4269 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4270 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
4271 " %<longjmp%> or %<vfork%>", decl
);
4274 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
4275 setjmp_vars_warning (setjmp_crosses
, sub
);
4278 /* Do the appropriate part of setjmp_vars_warning
4279 but for arguments instead of local variables. */
4282 setjmp_args_warning (bitmap setjmp_crosses
)
4285 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4286 decl
; decl
= DECL_CHAIN (decl
))
4287 if (DECL_RTL (decl
) != 0
4288 && REG_P (DECL_RTL (decl
))
4289 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4290 warning (OPT_Wclobbered
,
4291 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4295 /* Generate warning messages for variables live across setjmp. */
4298 generate_setjmp_warnings (void)
4300 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
4302 if (n_basic_blocks_for_fn (cfun
) == NUM_FIXED_BLOCKS
4303 || bitmap_empty_p (setjmp_crosses
))
4306 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
4307 setjmp_args_warning (setjmp_crosses
);
4311 /* Reverse the order of elements in the fragment chain T of blocks,
4312 and return the new head of the chain (old last element).
4313 In addition to that clear BLOCK_SAME_RANGE flags when needed
4314 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4315 its super fragment origin. */
4318 block_fragments_nreverse (tree t
)
4320 tree prev
= 0, block
, next
, prev_super
= 0;
4321 tree super
= BLOCK_SUPERCONTEXT (t
);
4322 if (BLOCK_FRAGMENT_ORIGIN (super
))
4323 super
= BLOCK_FRAGMENT_ORIGIN (super
);
4324 for (block
= t
; block
; block
= next
)
4326 next
= BLOCK_FRAGMENT_CHAIN (block
);
4327 BLOCK_FRAGMENT_CHAIN (block
) = prev
;
4328 if ((prev
&& !BLOCK_SAME_RANGE (prev
))
4329 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block
))
4331 BLOCK_SAME_RANGE (block
) = 0;
4332 prev_super
= BLOCK_SUPERCONTEXT (block
);
4333 BLOCK_SUPERCONTEXT (block
) = super
;
4336 t
= BLOCK_FRAGMENT_ORIGIN (t
);
4337 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t
))
4339 BLOCK_SAME_RANGE (t
) = 0;
4340 BLOCK_SUPERCONTEXT (t
) = super
;
4344 /* Reverse the order of elements in the chain T of blocks,
4345 and return the new head of the chain (old last element).
4346 Also do the same on subblocks and reverse the order of elements
4347 in BLOCK_FRAGMENT_CHAIN as well. */
4350 blocks_nreverse_all (tree t
)
4352 tree prev
= 0, block
, next
;
4353 for (block
= t
; block
; block
= next
)
4355 next
= BLOCK_CHAIN (block
);
4356 BLOCK_CHAIN (block
) = prev
;
4357 if (BLOCK_FRAGMENT_CHAIN (block
)
4358 && BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
)
4360 BLOCK_FRAGMENT_CHAIN (block
)
4361 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block
));
4362 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block
)))
4363 BLOCK_SAME_RANGE (block
) = 0;
4365 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4372 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4373 and create duplicate blocks. */
4374 /* ??? Need an option to either create block fragments or to create
4375 abstract origin duplicates of a source block. It really depends
4376 on what optimization has been performed. */
4379 reorder_blocks (void)
4381 tree block
= DECL_INITIAL (current_function_decl
);
4383 if (block
== NULL_TREE
)
4386 auto_vec
<tree
, 10> block_stack
;
4388 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4389 clear_block_marks (block
);
4391 /* Prune the old trees away, so that they don't get in the way. */
4392 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
4393 BLOCK_CHAIN (block
) = NULL_TREE
;
4395 /* Recreate the block tree from the note nesting. */
4396 reorder_blocks_1 (get_insns (), block
, &block_stack
);
4397 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4400 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4403 clear_block_marks (tree block
)
4407 TREE_ASM_WRITTEN (block
) = 0;
4408 clear_block_marks (BLOCK_SUBBLOCKS (block
));
4409 block
= BLOCK_CHAIN (block
);
4414 reorder_blocks_1 (rtx_insn
*insns
, tree current_block
,
4415 vec
<tree
> *p_block_stack
)
4418 tree prev_beg
= NULL_TREE
, prev_end
= NULL_TREE
;
4420 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
4424 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
4426 tree block
= NOTE_BLOCK (insn
);
4429 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
);
4433 BLOCK_SAME_RANGE (prev_end
) = 0;
4434 prev_end
= NULL_TREE
;
4436 /* If we have seen this block before, that means it now
4437 spans multiple address regions. Create a new fragment. */
4438 if (TREE_ASM_WRITTEN (block
))
4440 tree new_block
= copy_node (block
);
4442 BLOCK_SAME_RANGE (new_block
) = 0;
4443 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
4444 BLOCK_FRAGMENT_CHAIN (new_block
)
4445 = BLOCK_FRAGMENT_CHAIN (origin
);
4446 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
4448 NOTE_BLOCK (insn
) = new_block
;
4452 if (prev_beg
== current_block
&& prev_beg
)
4453 BLOCK_SAME_RANGE (block
) = 1;
4457 BLOCK_SUBBLOCKS (block
) = 0;
4458 TREE_ASM_WRITTEN (block
) = 1;
4459 /* When there's only one block for the entire function,
4460 current_block == block and we mustn't do this, it
4461 will cause infinite recursion. */
4462 if (block
!= current_block
)
4465 if (block
!= origin
)
4466 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
4467 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4470 if (p_block_stack
->is_empty ())
4471 super
= current_block
;
4474 super
= p_block_stack
->last ();
4475 gcc_assert (super
== current_block
4476 || BLOCK_FRAGMENT_ORIGIN (super
)
4479 BLOCK_SUPERCONTEXT (block
) = super
;
4480 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
4481 BLOCK_SUBBLOCKS (current_block
) = block
;
4482 current_block
= origin
;
4484 p_block_stack
->safe_push (block
);
4486 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
4488 NOTE_BLOCK (insn
) = p_block_stack
->pop ();
4489 current_block
= BLOCK_SUPERCONTEXT (current_block
);
4490 if (BLOCK_FRAGMENT_ORIGIN (current_block
))
4491 current_block
= BLOCK_FRAGMENT_ORIGIN (current_block
);
4492 prev_beg
= NULL_TREE
;
4493 prev_end
= BLOCK_SAME_RANGE (NOTE_BLOCK (insn
))
4494 ? NOTE_BLOCK (insn
) : NULL_TREE
;
4499 prev_beg
= NULL_TREE
;
4501 BLOCK_SAME_RANGE (prev_end
) = 0;
4502 prev_end
= NULL_TREE
;
4507 /* Reverse the order of elements in the chain T of blocks,
4508 and return the new head of the chain (old last element). */
4511 blocks_nreverse (tree t
)
4513 tree prev
= 0, block
, next
;
4514 for (block
= t
; block
; block
= next
)
4516 next
= BLOCK_CHAIN (block
);
4517 BLOCK_CHAIN (block
) = prev
;
4523 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4524 by modifying the last node in chain 1 to point to chain 2. */
4527 block_chainon (tree op1
, tree op2
)
4536 for (t1
= op1
; BLOCK_CHAIN (t1
); t1
= BLOCK_CHAIN (t1
))
4538 BLOCK_CHAIN (t1
) = op2
;
4540 #ifdef ENABLE_TREE_CHECKING
4543 for (t2
= op2
; t2
; t2
= BLOCK_CHAIN (t2
))
4544 gcc_assert (t2
!= t1
);
4551 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4552 non-NULL, list them all into VECTOR, in a depth-first preorder
4553 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4557 all_blocks (tree block
, tree
*vector
)
4563 TREE_ASM_WRITTEN (block
) = 0;
4565 /* Record this block. */
4567 vector
[n_blocks
] = block
;
4571 /* Record the subblocks, and their subblocks... */
4572 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
4573 vector
? vector
+ n_blocks
: 0);
4574 block
= BLOCK_CHAIN (block
);
4580 /* Return a vector containing all the blocks rooted at BLOCK. The
4581 number of elements in the vector is stored in N_BLOCKS_P. The
4582 vector is dynamically allocated; it is the caller's responsibility
4583 to call `free' on the pointer returned. */
4586 get_block_vector (tree block
, int *n_blocks_p
)
4590 *n_blocks_p
= all_blocks (block
, NULL
);
4591 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
4592 all_blocks (block
, block_vector
);
4594 return block_vector
;
4597 static GTY(()) int next_block_index
= 2;
4599 /* Set BLOCK_NUMBER for all the blocks in FN. */
4602 number_blocks (tree fn
)
4608 /* For XCOFF debugging output, we start numbering the blocks
4609 from 1 within each function, rather than keeping a running
4611 #if defined (XCOFF_DEBUGGING_INFO)
4612 if (write_symbols
== XCOFF_DEBUG
)
4613 next_block_index
= 1;
4616 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
4618 /* The top-level BLOCK isn't numbered at all. */
4619 for (i
= 1; i
< n_blocks
; ++i
)
4620 /* We number the blocks from two. */
4621 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
4623 free (block_vector
);
4628 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4631 debug_find_var_in_block_tree (tree var
, tree block
)
4635 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4639 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4641 tree ret
= debug_find_var_in_block_tree (var
, t
);
4649 /* Keep track of whether we're in a dummy function context. If we are,
4650 we don't want to invoke the set_current_function hook, because we'll
4651 get into trouble if the hook calls target_reinit () recursively or
4652 when the initial initialization is not yet complete. */
4654 static bool in_dummy_function
;
4656 /* Invoke the target hook when setting cfun. Update the optimization options
4657 if the function uses different options than the default. */
4660 invoke_set_current_function_hook (tree fndecl
)
4662 if (!in_dummy_function
)
4664 tree opts
= ((fndecl
)
4665 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4666 : optimization_default_node
);
4669 opts
= optimization_default_node
;
4671 /* Change optimization options if needed. */
4672 if (optimization_current_node
!= opts
)
4674 optimization_current_node
= opts
;
4675 cl_optimization_restore (&global_options
, &global_options_set
,
4676 TREE_OPTIMIZATION (opts
));
4679 targetm
.set_current_function (fndecl
);
4680 this_fn_optabs
= this_target_optabs
;
4682 /* Initialize global alignment variables after op. */
4683 parse_alignment_opts ();
4685 if (opts
!= optimization_default_node
)
4687 init_tree_optimization_optabs (opts
);
4688 if (TREE_OPTIMIZATION_OPTABS (opts
))
4689 this_fn_optabs
= (struct target_optabs
*)
4690 TREE_OPTIMIZATION_OPTABS (opts
);
4695 /* cfun should never be set directly; use this function. */
4698 set_cfun (struct function
*new_cfun
, bool force
)
4700 if (cfun
!= new_cfun
|| force
)
4703 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4704 redirect_edge_var_map_empty ();
4708 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4710 static vec
<function
*> cfun_stack
;
4712 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4713 current_function_decl accordingly. */
4716 push_cfun (struct function
*new_cfun
)
4718 gcc_assert ((!cfun
&& !current_function_decl
)
4719 || (cfun
&& current_function_decl
== cfun
->decl
));
4720 cfun_stack
.safe_push (cfun
);
4721 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4722 set_cfun (new_cfun
);
4725 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4730 struct function
*new_cfun
= cfun_stack
.pop ();
4731 /* When in_dummy_function, we do have a cfun but current_function_decl is
4732 NULL. We also allow pushing NULL cfun and subsequently changing
4733 current_function_decl to something else and have both restored by
4735 gcc_checking_assert (in_dummy_function
4737 || current_function_decl
== cfun
->decl
);
4738 set_cfun (new_cfun
);
4739 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4742 /* Return value of funcdef and increase it. */
4744 get_next_funcdef_no (void)
4746 return funcdef_no
++;
4749 /* Return value of funcdef. */
4751 get_last_funcdef_no (void)
4756 /* Allocate and initialize the stack usage info data structure for the
4757 current function. */
4759 allocate_stack_usage_info (void)
4761 gcc_assert (!cfun
->su
);
4762 cfun
->su
= ggc_cleared_alloc
<stack_usage
> ();
4763 cfun
->su
->static_stack_size
= -1;
4766 /* Allocate a function structure for FNDECL and set its contents
4767 to the defaults. Set cfun to the newly-allocated object.
4768 Some of the helper functions invoked during initialization assume
4769 that cfun has already been set. Therefore, assign the new object
4770 directly into cfun and invoke the back end hook explicitly at the
4771 very end, rather than initializing a temporary and calling set_cfun
4774 ABSTRACT_P is true if this is a function that will never be seen by
4775 the middle-end. Such functions are front-end concepts (like C++
4776 function templates) that do not correspond directly to functions
4777 placed in object files. */
4780 allocate_struct_function (tree fndecl
, bool abstract_p
)
4782 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4784 cfun
= ggc_cleared_alloc
<function
> ();
4786 init_eh_for_function ();
4788 if (init_machine_status
)
4789 cfun
->machine
= (*init_machine_status
) ();
4791 #ifdef OVERRIDE_ABI_FORMAT
4792 OVERRIDE_ABI_FORMAT (fndecl
);
4795 if (fndecl
!= NULL_TREE
)
4797 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4798 cfun
->decl
= fndecl
;
4799 current_function_funcdef_no
= get_next_funcdef_no ();
4802 invoke_set_current_function_hook (fndecl
);
4804 if (fndecl
!= NULL_TREE
)
4806 tree result
= DECL_RESULT (fndecl
);
4810 /* Now that we have activated any function-specific attributes
4811 that might affect layout, particularly vector modes, relayout
4812 each of the parameters and the result. */
4813 relayout_decl (result
);
4814 for (tree parm
= DECL_ARGUMENTS (fndecl
); parm
;
4815 parm
= DECL_CHAIN (parm
))
4816 relayout_decl (parm
);
4818 /* Similarly relayout the function decl. */
4819 targetm
.target_option
.relayout_function (fndecl
);
4822 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4824 #ifdef PCC_STATIC_STRUCT_RETURN
4825 cfun
->returns_pcc_struct
= 1;
4827 cfun
->returns_struct
= 1;
4830 cfun
->stdarg
= stdarg_p (fntype
);
4832 /* Assume all registers in stdarg functions need to be saved. */
4833 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4834 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4836 /* ??? This could be set on a per-function basis by the front-end
4837 but is this worth the hassle? */
4838 cfun
->can_throw_non_call_exceptions
= flag_non_call_exceptions
;
4839 cfun
->can_delete_dead_exceptions
= flag_delete_dead_exceptions
;
4841 if (!profile_flag
&& !flag_instrument_function_entry_exit
)
4842 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl
) = 1;
4844 if (flag_callgraph_info
)
4845 allocate_stack_usage_info ();
4848 /* Don't enable begin stmt markers if var-tracking at assignments is
4849 disabled. The markers make little sense without the variable
4850 binding annotations among them. */
4851 cfun
->debug_nonbind_markers
= lang_hooks
.emits_begin_stmt
4852 && MAY_HAVE_DEBUG_MARKER_STMTS
;
4855 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4856 instead of just setting it. */
4859 push_struct_function (tree fndecl
)
4861 /* When in_dummy_function we might be in the middle of a pop_cfun and
4862 current_function_decl and cfun may not match. */
4863 gcc_assert (in_dummy_function
4864 || (!cfun
&& !current_function_decl
)
4865 || (cfun
&& current_function_decl
== cfun
->decl
));
4866 cfun_stack
.safe_push (cfun
);
4867 current_function_decl
= fndecl
;
4868 allocate_struct_function (fndecl
, false);
4871 /* Reset crtl and other non-struct-function variables to defaults as
4872 appropriate for emitting rtl at the start of a function. */
4875 prepare_function_start (void)
4877 gcc_assert (!get_last_insn ());
4879 if (in_dummy_function
)
4880 crtl
->abi
= &default_function_abi
;
4882 crtl
->abi
= &fndecl_abi (cfun
->decl
).base_abi ();
4886 init_varasm_status ();
4888 default_rtl_profile ();
4890 if (flag_stack_usage_info
&& !flag_callgraph_info
)
4891 allocate_stack_usage_info ();
4893 cse_not_expected
= ! optimize
;
4895 /* Caller save not needed yet. */
4896 caller_save_needed
= 0;
4898 /* We haven't done register allocation yet. */
4901 /* Indicate that we have not instantiated virtual registers yet. */
4902 virtuals_instantiated
= 0;
4904 /* Indicate that we want CONCATs now. */
4905 generating_concat_p
= 1;
4907 /* Indicate we have no need of a frame pointer yet. */
4908 frame_pointer_needed
= 0;
4912 push_dummy_function (bool with_decl
)
4914 tree fn_decl
, fn_type
, fn_result_decl
;
4916 gcc_assert (!in_dummy_function
);
4917 in_dummy_function
= true;
4921 fn_type
= build_function_type_list (void_type_node
, NULL_TREE
);
4922 fn_decl
= build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
, NULL_TREE
,
4924 fn_result_decl
= build_decl (UNKNOWN_LOCATION
, RESULT_DECL
,
4925 NULL_TREE
, void_type_node
);
4926 DECL_RESULT (fn_decl
) = fn_result_decl
;
4929 fn_decl
= NULL_TREE
;
4931 push_struct_function (fn_decl
);
4934 /* Initialize the rtl expansion mechanism so that we can do simple things
4935 like generate sequences. This is used to provide a context during global
4936 initialization of some passes. You must call expand_dummy_function_end
4937 to exit this context. */
4940 init_dummy_function_start (void)
4942 push_dummy_function (false);
4943 prepare_function_start ();
4946 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4947 and initialize static variables for generating RTL for the statements
4951 init_function_start (tree subr
)
4953 /* Initialize backend, if needed. */
4956 prepare_function_start ();
4957 decide_function_section (subr
);
4959 /* Warn if this value is an aggregate type,
4960 regardless of which calling convention we are using for it. */
4961 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4962 warning (OPT_Waggregate_return
, "function returns an aggregate");
4965 /* Expand code to verify the stack_protect_guard. This is invoked at
4966 the end of a function to be protected. */
4969 stack_protect_epilogue (void)
4971 tree guard_decl
= crtl
->stack_protect_guard_decl
;
4972 rtx_code_label
*label
= gen_label_rtx ();
4974 rtx_insn
*seq
= NULL
;
4976 x
= expand_normal (crtl
->stack_protect_guard
);
4978 if (targetm
.have_stack_protect_combined_test () && guard_decl
)
4980 gcc_assert (DECL_P (guard_decl
));
4981 y
= DECL_RTL (guard_decl
);
4982 /* Allow the target to compute address of Y and compare it with X without
4983 leaking Y into a register. This combined address + compare pattern
4984 allows the target to prevent spilling of any intermediate results by
4985 splitting it after register allocator. */
4986 seq
= targetm
.gen_stack_protect_combined_test (x
, y
, label
);
4991 y
= expand_normal (guard_decl
);
4995 /* Allow the target to compare Y with X without leaking either into
4997 if (targetm
.have_stack_protect_test ())
4998 seq
= targetm
.gen_stack_protect_test (x
, y
, label
);
5004 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
5006 /* The noreturn predictor has been moved to the tree level. The rtl-level
5007 predictors estimate this branch about 20%, which isn't enough to get
5008 things moved out of line. Since this is the only extant case of adding
5009 a noreturn function at the rtl level, it doesn't seem worth doing ought
5010 except adding the prediction by hand. */
5011 rtx_insn
*tmp
= get_last_insn ();
5013 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
5015 expand_call (targetm
.stack_protect_fail (), NULL_RTX
, /*ignore=*/true);
5020 /* Start the RTL for a new function, and set variables used for
5022 SUBR is the FUNCTION_DECL node.
5023 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5024 the function's parameters, which must be run at any return statement. */
5027 expand_function_start (tree subr
)
5029 /* Make sure volatile mem refs aren't considered
5030 valid operands of arithmetic insns. */
5031 init_recog_no_volatile ();
5035 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
5038 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
5040 /* Make the label for return statements to jump to. Do not special
5041 case machines with special return instructions -- they will be
5042 handled later during jump, ifcvt, or epilogue creation. */
5043 return_label
= gen_label_rtx ();
5045 /* Initialize rtx used to return the value. */
5046 /* Do this before assign_parms so that we copy the struct value address
5047 before any library calls that assign parms might generate. */
5049 /* Decide whether to return the value in memory or in a register. */
5050 tree res
= DECL_RESULT (subr
);
5051 if (aggregate_value_p (res
, subr
))
5053 /* Returning something that won't go in a register. */
5054 rtx value_address
= 0;
5056 #ifdef PCC_STATIC_STRUCT_RETURN
5057 if (cfun
->returns_pcc_struct
)
5059 int size
= int_size_in_bytes (TREE_TYPE (res
));
5060 value_address
= assemble_static_space (size
);
5065 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
5066 /* Expect to be passed the address of a place to store the value.
5067 If it is passed as an argument, assign_parms will take care of
5071 value_address
= gen_reg_rtx (Pmode
);
5072 emit_move_insn (value_address
, sv
);
5077 rtx x
= value_address
;
5078 if (!DECL_BY_REFERENCE (res
))
5080 x
= gen_rtx_MEM (DECL_MODE (res
), x
);
5081 set_mem_attributes (x
, res
, 1);
5083 set_parm_rtl (res
, x
);
5086 else if (DECL_MODE (res
) == VOIDmode
)
5087 /* If return mode is void, this decl rtl should not be used. */
5088 set_parm_rtl (res
, NULL_RTX
);
5091 /* Compute the return values into a pseudo reg, which we will copy
5092 into the true return register after the cleanups are done. */
5093 tree return_type
= TREE_TYPE (res
);
5095 /* If we may coalesce this result, make sure it has the expected mode
5096 in case it was promoted. But we need not bother about BLKmode. */
5097 machine_mode promoted_mode
5098 = flag_tree_coalesce_vars
&& is_gimple_reg (res
)
5099 ? promote_ssa_mode (ssa_default_def (cfun
, res
), NULL
)
5102 if (promoted_mode
!= BLKmode
)
5103 set_parm_rtl (res
, gen_reg_rtx (promoted_mode
));
5104 else if (TYPE_MODE (return_type
) != BLKmode
5105 && targetm
.calls
.return_in_msb (return_type
))
5106 /* expand_function_end will insert the appropriate padding in
5107 this case. Use the return value's natural (unpadded) mode
5108 within the function proper. */
5109 set_parm_rtl (res
, gen_reg_rtx (TYPE_MODE (return_type
)));
5112 /* In order to figure out what mode to use for the pseudo, we
5113 figure out what the mode of the eventual return register will
5114 actually be, and use that. */
5115 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
5117 /* Structures that are returned in registers are not
5118 aggregate_value_p, so we may see a PARALLEL or a REG. */
5119 if (REG_P (hard_reg
))
5120 set_parm_rtl (res
, gen_reg_rtx (GET_MODE (hard_reg
)));
5123 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
5124 set_parm_rtl (res
, gen_group_rtx (hard_reg
));
5128 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5129 result to the real return register(s). */
5130 DECL_REGISTER (res
) = 1;
5133 /* Initialize rtx for parameters and local variables.
5134 In some cases this requires emitting insns. */
5135 assign_parms (subr
);
5137 /* If function gets a static chain arg, store it. */
5138 if (cfun
->static_chain_decl
)
5140 tree parm
= cfun
->static_chain_decl
;
5145 local
= gen_reg_rtx (promote_decl_mode (parm
, &unsignedp
));
5146 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
5148 set_decl_incoming_rtl (parm
, chain
, false);
5149 set_parm_rtl (parm
, local
);
5150 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
5152 if (GET_MODE (local
) != GET_MODE (chain
))
5154 convert_move (local
, chain
, unsignedp
);
5155 insn
= get_last_insn ();
5158 insn
= emit_move_insn (local
, chain
);
5160 /* Mark the register as eliminable, similar to parameters. */
5162 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
5163 set_dst_reg_note (insn
, REG_EQUIV
, chain
, local
);
5165 /* If we aren't optimizing, save the static chain onto the stack. */
5168 tree saved_static_chain_decl
5169 = build_decl (DECL_SOURCE_LOCATION (parm
), VAR_DECL
,
5170 DECL_NAME (parm
), TREE_TYPE (parm
));
5171 rtx saved_static_chain_rtx
5172 = assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5173 SET_DECL_RTL (saved_static_chain_decl
, saved_static_chain_rtx
);
5174 emit_move_insn (saved_static_chain_rtx
, chain
);
5175 SET_DECL_VALUE_EXPR (parm
, saved_static_chain_decl
);
5176 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
5180 /* The following was moved from init_function_start.
5181 The move was supposed to make sdb output more accurate. */
5182 /* Indicate the beginning of the function body,
5183 as opposed to parm setup. */
5184 emit_note (NOTE_INSN_FUNCTION_BEG
);
5186 gcc_assert (NOTE_P (get_last_insn ()));
5188 parm_birth_insn
= get_last_insn ();
5190 /* If the function receives a non-local goto, then store the
5191 bits we need to restore the frame pointer. */
5192 if (cfun
->nonlocal_goto_save_area
)
5197 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
5198 gcc_assert (DECL_RTL_SET_P (var
));
5200 t_save
= build4 (ARRAY_REF
,
5201 TREE_TYPE (TREE_TYPE (cfun
->nonlocal_goto_save_area
)),
5202 cfun
->nonlocal_goto_save_area
,
5203 integer_zero_node
, NULL_TREE
, NULL_TREE
);
5204 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
5205 gcc_assert (GET_MODE (r_save
) == Pmode
);
5207 emit_move_insn (r_save
, hard_frame_pointer_rtx
);
5208 update_nonlocal_goto_save_area ();
5214 PROFILE_HOOK (current_function_funcdef_no
);
5218 /* If we are doing generic stack checking, the probe should go here. */
5219 if (flag_stack_check
== GENERIC_STACK_CHECK
)
5220 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
5224 pop_dummy_function (void)
5227 in_dummy_function
= false;
5230 /* Undo the effects of init_dummy_function_start. */
5232 expand_dummy_function_end (void)
5234 gcc_assert (in_dummy_function
);
5236 /* End any sequences that failed to be closed due to syntax errors. */
5237 while (in_sequence_p ())
5240 /* Outside function body, can't compute type's actual size
5241 until next function's body starts. */
5243 free_after_parsing (cfun
);
5244 free_after_compilation (cfun
);
5245 pop_dummy_function ();
5248 /* Helper for diddle_return_value. */
5251 diddle_return_value_1 (void (*doit
) (rtx
, void *), void *arg
, rtx outgoing
)
5256 if (REG_P (outgoing
))
5257 (*doit
) (outgoing
, arg
);
5258 else if (GET_CODE (outgoing
) == PARALLEL
)
5262 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
5264 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
5266 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
5272 /* Call DOIT for each hard register used as a return value from
5273 the current function. */
5276 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
5278 diddle_return_value_1 (doit
, arg
, crtl
->return_rtx
);
5282 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
5288 clobber_return_register (void)
5290 diddle_return_value (do_clobber_return_reg
, NULL
);
5292 /* In case we do use pseudo to return value, clobber it too. */
5293 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5295 tree decl_result
= DECL_RESULT (current_function_decl
);
5296 rtx decl_rtl
= DECL_RTL (decl_result
);
5297 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
5299 do_clobber_return_reg (decl_rtl
, NULL
);
5305 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
5311 use_return_register (void)
5313 diddle_return_value (do_use_return_reg
, NULL
);
5316 /* Generate RTL for the end of the current function. */
5319 expand_function_end (void)
5321 /* If arg_pointer_save_area was referenced only from a nested
5322 function, we will not have initialized it yet. Do that now. */
5323 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
5324 get_arg_pointer_save_area ();
5326 /* If we are doing generic stack checking and this function makes calls,
5327 do a stack probe at the start of the function to ensure we have enough
5328 space for another stack frame. */
5329 if (flag_stack_check
== GENERIC_STACK_CHECK
)
5331 rtx_insn
*insn
, *seq
;
5333 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5336 rtx max_frame_size
= GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
);
5338 if (STACK_CHECK_MOVING_SP
)
5339 anti_adjust_stack_and_probe (max_frame_size
, true);
5341 probe_stack_range (STACK_OLD_CHECK_PROTECT
, max_frame_size
);
5344 set_insn_locations (seq
, prologue_location
);
5345 emit_insn_before (seq
, stack_check_probe_note
);
5350 /* End any sequences that failed to be closed due to syntax errors. */
5351 while (in_sequence_p ())
5354 clear_pending_stack_adjust ();
5355 do_pending_stack_adjust ();
5357 /* Output a linenumber for the end of the function.
5358 SDB depended on this. */
5359 set_curr_insn_location (input_location
);
5361 /* Before the return label (if any), clobber the return
5362 registers so that they are not propagated live to the rest of
5363 the function. This can only happen with functions that drop
5364 through; if there had been a return statement, there would
5365 have either been a return rtx, or a jump to the return label.
5367 We delay actual code generation after the current_function_value_rtx
5369 rtx_insn
*clobber_after
= get_last_insn ();
5371 /* Output the label for the actual return from the function. */
5372 emit_label (return_label
);
5374 if (targetm_common
.except_unwind_info (&global_options
) == UI_SJLJ
)
5376 /* Let except.c know where it should emit the call to unregister
5377 the function context for sjlj exceptions. */
5378 if (flag_exceptions
)
5379 sjlj_emit_function_exit_after (get_last_insn ());
5382 /* If this is an implementation of throw, do what's necessary to
5383 communicate between __builtin_eh_return and the epilogue. */
5384 expand_eh_return ();
5386 /* If stack protection is enabled for this function, check the guard. */
5387 if (crtl
->stack_protect_guard
5388 && targetm
.stack_protect_runtime_enabled_p ()
5389 && naked_return_label
== NULL_RTX
)
5390 stack_protect_epilogue ();
5392 /* If scalar return value was computed in a pseudo-reg, or was a named
5393 return value that got dumped to the stack, copy that to the hard
5395 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5397 tree decl_result
= DECL_RESULT (current_function_decl
);
5398 rtx decl_rtl
= DECL_RTL (decl_result
);
5400 if (REG_P (decl_rtl
)
5401 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
5402 : DECL_REGISTER (decl_result
))
5404 rtx real_decl_rtl
= crtl
->return_rtx
;
5407 /* This should be set in assign_parms. */
5408 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
5410 /* If this is a BLKmode structure being returned in registers,
5411 then use the mode computed in expand_return. Note that if
5412 decl_rtl is memory, then its mode may have been changed,
5413 but that crtl->return_rtx has not. */
5414 if (GET_MODE (real_decl_rtl
) == BLKmode
)
5415 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
5417 /* If a non-BLKmode return value should be padded at the least
5418 significant end of the register, shift it left by the appropriate
5419 amount. BLKmode results are handled using the group load/store
5421 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
5422 && REG_P (real_decl_rtl
)
5423 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
5425 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
5426 REGNO (real_decl_rtl
)),
5428 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
5430 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
5432 /* If expand_function_start has created a PARALLEL for decl_rtl,
5433 move the result to the real return registers. Otherwise, do
5434 a group load from decl_rtl for a named return. */
5435 if (GET_CODE (decl_rtl
) == PARALLEL
)
5436 emit_group_move (real_decl_rtl
, decl_rtl
);
5438 emit_group_load (real_decl_rtl
, decl_rtl
,
5439 TREE_TYPE (decl_result
),
5440 int_size_in_bytes (TREE_TYPE (decl_result
)));
5442 /* In the case of complex integer modes smaller than a word, we'll
5443 need to generate some non-trivial bitfield insertions. Do that
5444 on a pseudo and not the hard register. */
5445 else if (GET_CODE (decl_rtl
) == CONCAT
5446 && is_complex_int_mode (GET_MODE (decl_rtl
), &cmode
)
5447 && GET_MODE_BITSIZE (cmode
) <= BITS_PER_WORD
)
5449 int old_generating_concat_p
;
5452 old_generating_concat_p
= generating_concat_p
;
5453 generating_concat_p
= 0;
5454 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
5455 generating_concat_p
= old_generating_concat_p
;
5457 emit_move_insn (tmp
, decl_rtl
);
5458 emit_move_insn (real_decl_rtl
, tmp
);
5460 /* If a named return value dumped decl_return to memory, then
5461 we may need to re-do the PROMOTE_MODE signed/unsigned
5463 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
5465 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
5466 promote_function_mode (TREE_TYPE (decl_result
),
5467 GET_MODE (decl_rtl
), &unsignedp
,
5468 TREE_TYPE (current_function_decl
), 1);
5470 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
5473 emit_move_insn (real_decl_rtl
, decl_rtl
);
5477 /* If returning a structure, arrange to return the address of the value
5478 in a place where debuggers expect to find it.
5480 If returning a structure PCC style,
5481 the caller also depends on this value.
5482 And cfun->returns_pcc_struct is not necessarily set. */
5483 if ((cfun
->returns_struct
|| cfun
->returns_pcc_struct
)
5484 && !targetm
.calls
.omit_struct_return_reg
)
5486 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
5487 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5490 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
5491 type
= TREE_TYPE (type
);
5493 value_address
= XEXP (value_address
, 0);
5495 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
5496 current_function_decl
, true);
5498 /* Mark this as a function return value so integrate will delete the
5499 assignment and USE below when inlining this function. */
5500 REG_FUNCTION_VALUE_P (outgoing
) = 1;
5502 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5503 scalar_int_mode mode
= as_a
<scalar_int_mode
> (GET_MODE (outgoing
));
5504 value_address
= convert_memory_address (mode
, value_address
);
5506 emit_move_insn (outgoing
, value_address
);
5508 /* Show return register used to hold result (in this case the address
5510 crtl
->return_rtx
= outgoing
;
5513 /* Emit the actual code to clobber return register. Don't emit
5514 it if clobber_after is a barrier, then the previous basic block
5515 certainly doesn't fall thru into the exit block. */
5516 if (!BARRIER_P (clobber_after
))
5519 clobber_return_register ();
5520 rtx_insn
*seq
= get_insns ();
5523 emit_insn_after (seq
, clobber_after
);
5526 /* Output the label for the naked return from the function. */
5527 if (naked_return_label
)
5528 emit_label (naked_return_label
);
5530 /* @@@ This is a kludge. We want to ensure that instructions that
5531 may trap are not moved into the epilogue by scheduling, because
5532 we don't always emit unwind information for the epilogue. */
5533 if (cfun
->can_throw_non_call_exceptions
5534 && targetm_common
.except_unwind_info (&global_options
) != UI_SJLJ
)
5535 emit_insn (gen_blockage ());
5537 /* If stack protection is enabled for this function, check the guard. */
5538 if (crtl
->stack_protect_guard
5539 && targetm
.stack_protect_runtime_enabled_p ()
5540 && naked_return_label
)
5541 stack_protect_epilogue ();
5543 /* If we had calls to alloca, and this machine needs
5544 an accurate stack pointer to exit the function,
5545 insert some code to save and restore the stack pointer. */
5546 if (! EXIT_IGNORE_STACK
5547 && cfun
->calls_alloca
)
5552 emit_stack_save (SAVE_FUNCTION
, &tem
);
5553 rtx_insn
*seq
= get_insns ();
5555 emit_insn_before (seq
, parm_birth_insn
);
5557 emit_stack_restore (SAVE_FUNCTION
, tem
);
5560 /* ??? This should no longer be necessary since stupid is no longer with
5561 us, but there are some parts of the compiler (eg reload_combine, and
5562 sh mach_dep_reorg) that still try and compute their own lifetime info
5563 instead of using the general framework. */
5564 use_return_register ();
5568 get_arg_pointer_save_area (void)
5570 rtx ret
= arg_pointer_save_area
;
5574 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5575 arg_pointer_save_area
= ret
;
5578 if (! crtl
->arg_pointer_save_area_init
)
5580 /* Save the arg pointer at the beginning of the function. The
5581 generated stack slot may not be a valid memory address, so we
5582 have to check it and fix it if necessary. */
5584 emit_move_insn (validize_mem (copy_rtx (ret
)),
5585 crtl
->args
.internal_arg_pointer
);
5586 rtx_insn
*seq
= get_insns ();
5589 push_topmost_sequence ();
5590 emit_insn_after (seq
, entry_of_function ());
5591 pop_topmost_sequence ();
5593 crtl
->arg_pointer_save_area_init
= true;
5600 /* If debugging dumps are requested, dump information about how the
5601 target handled -fstack-check=clash for the prologue.
5603 PROBES describes what if any probes were emitted.
5605 RESIDUALS indicates if the prologue had any residual allocation
5606 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5609 dump_stack_clash_frame_info (enum stack_clash_probes probes
, bool residuals
)
5616 case NO_PROBE_NO_FRAME
:
5618 "Stack clash no probe no stack adjustment in prologue.\n");
5620 case NO_PROBE_SMALL_FRAME
:
5622 "Stack clash no probe small stack adjustment in prologue.\n");
5625 fprintf (dump_file
, "Stack clash inline probes in prologue.\n");
5628 fprintf (dump_file
, "Stack clash probe loop in prologue.\n");
5633 fprintf (dump_file
, "Stack clash residual allocation in prologue.\n");
5635 fprintf (dump_file
, "Stack clash no residual allocation in prologue.\n");
5637 if (frame_pointer_needed
)
5638 fprintf (dump_file
, "Stack clash frame pointer needed.\n");
5640 fprintf (dump_file
, "Stack clash no frame pointer needed.\n");
5642 if (TREE_THIS_VOLATILE (cfun
->decl
))
5644 "Stack clash noreturn prologue, assuming no implicit"
5645 " probes in caller.\n");
5648 "Stack clash not noreturn prologue.\n");
5651 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5652 for the first time. */
5655 record_insns (rtx_insn
*insns
, rtx end
, hash_table
<insn_cache_hasher
> **hashp
)
5658 hash_table
<insn_cache_hasher
> *hash
= *hashp
;
5661 *hashp
= hash
= hash_table
<insn_cache_hasher
>::create_ggc (17);
5663 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
5665 rtx
*slot
= hash
->find_slot (tmp
, INSERT
);
5666 gcc_assert (*slot
== NULL
);
5671 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5672 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5673 insn, then record COPY as well. */
5676 maybe_copy_prologue_epilogue_insn (rtx insn
, rtx copy
)
5678 hash_table
<insn_cache_hasher
> *hash
;
5681 hash
= epilogue_insn_hash
;
5682 if (!hash
|| !hash
->find (insn
))
5684 hash
= prologue_insn_hash
;
5685 if (!hash
|| !hash
->find (insn
))
5689 slot
= hash
->find_slot (copy
, INSERT
);
5690 gcc_assert (*slot
== NULL
);
5694 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5695 we can be running after reorg, SEQUENCE rtl is possible. */
5698 contains (const rtx_insn
*insn
, hash_table
<insn_cache_hasher
> *hash
)
5703 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5705 rtx_sequence
*seq
= as_a
<rtx_sequence
*> (PATTERN (insn
));
5707 for (i
= seq
->len () - 1; i
>= 0; i
--)
5708 if (hash
->find (seq
->element (i
)))
5713 return hash
->find (const_cast<rtx_insn
*> (insn
)) != NULL
;
5717 prologue_contains (const rtx_insn
*insn
)
5719 return contains (insn
, prologue_insn_hash
);
5723 epilogue_contains (const rtx_insn
*insn
)
5725 return contains (insn
, epilogue_insn_hash
);
5729 prologue_epilogue_contains (const rtx_insn
*insn
)
5731 if (contains (insn
, prologue_insn_hash
))
5733 if (contains (insn
, epilogue_insn_hash
))
5739 record_prologue_seq (rtx_insn
*seq
)
5741 record_insns (seq
, NULL
, &prologue_insn_hash
);
5745 record_epilogue_seq (rtx_insn
*seq
)
5747 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5750 /* Set JUMP_LABEL for a return insn. */
5753 set_return_jump_label (rtx_insn
*returnjump
)
5755 rtx pat
= PATTERN (returnjump
);
5756 if (GET_CODE (pat
) == PARALLEL
)
5757 pat
= XVECEXP (pat
, 0, 0);
5758 if (ANY_RETURN_P (pat
))
5759 JUMP_LABEL (returnjump
) = pat
;
5761 JUMP_LABEL (returnjump
) = ret_rtx
;
5764 /* Return a sequence to be used as the split prologue for the current
5765 function, or NULL. */
5768 make_split_prologue_seq (void)
5770 if (!flag_split_stack
5771 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun
->decl
)))
5775 emit_insn (targetm
.gen_split_stack_prologue ());
5776 rtx_insn
*seq
= get_insns ();
5779 record_insns (seq
, NULL
, &prologue_insn_hash
);
5780 set_insn_locations (seq
, prologue_location
);
5785 /* Return a sequence to be used as the prologue for the current function,
5789 make_prologue_seq (void)
5791 if (!targetm
.have_prologue ())
5795 rtx_insn
*seq
= targetm
.gen_prologue ();
5798 /* Insert an explicit USE for the frame pointer
5799 if the profiling is on and the frame pointer is required. */
5800 if (crtl
->profile
&& frame_pointer_needed
)
5801 emit_use (hard_frame_pointer_rtx
);
5803 /* Retain a map of the prologue insns. */
5804 record_insns (seq
, NULL
, &prologue_insn_hash
);
5805 emit_note (NOTE_INSN_PROLOGUE_END
);
5807 /* Ensure that instructions are not moved into the prologue when
5808 profiling is on. The call to the profiling routine can be
5809 emitted within the live range of a call-clobbered register. */
5810 if (!targetm
.profile_before_prologue () && crtl
->profile
)
5811 emit_insn (gen_blockage ());
5815 set_insn_locations (seq
, prologue_location
);
5820 /* Emit a sequence of insns to zero the call-used registers before RET
5821 according to ZERO_REGS_TYPE. */
5824 gen_call_used_regs_seq (rtx_insn
*ret
, unsigned int zero_regs_type
)
5826 bool only_gpr
= true;
5827 bool only_used
= true;
5828 bool only_arg
= true;
5830 /* No need to zero call-used-regs in main (). */
5831 if (MAIN_NAME_P (DECL_NAME (current_function_decl
)))
5834 /* No need to zero call-used-regs if __builtin_eh_return is called
5835 since it isn't a normal function return. */
5836 if (crtl
->calls_eh_return
)
5839 /* If only_gpr is true, only zero call-used registers that are
5840 general-purpose registers; if only_used is true, only zero
5841 call-used registers that are used in the current function;
5842 if only_arg is true, only zero call-used registers that pass
5843 parameters defined by the flatform's calling conversion. */
5845 using namespace zero_regs_flags
;
5847 only_gpr
= zero_regs_type
& ONLY_GPR
;
5848 only_used
= zero_regs_type
& ONLY_USED
;
5849 only_arg
= zero_regs_type
& ONLY_ARG
;
5851 /* For each of the hard registers, we should zero it if:
5852 1. it is a call-used register;
5853 and 2. it is not a fixed register;
5854 and 3. it is not live at the return of the routine;
5855 and 4. it is general registor if only_gpr is true;
5856 and 5. it is used in the routine if only_used is true;
5857 and 6. it is a register that passes parameter if only_arg is true. */
5859 /* First, prepare the data flow information. */
5860 basic_block bb
= BLOCK_FOR_INSN (ret
);
5861 auto_bitmap live_out
;
5862 bitmap_copy (live_out
, df_get_live_out (bb
));
5863 df_simulate_initialize_backwards (bb
, live_out
);
5864 df_simulate_one_insn_backwards (bb
, ret
, live_out
);
5866 HARD_REG_SET selected_hardregs
;
5867 CLEAR_HARD_REG_SET (selected_hardregs
);
5868 for (unsigned int regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
5870 if (!crtl
->abi
->clobbers_full_reg_p (regno
))
5872 if (fixed_regs
[regno
])
5874 if (REGNO_REG_SET_P (live_out
, regno
))
5877 && !TEST_HARD_REG_BIT (reg_class_contents
[GENERAL_REGS
], regno
))
5879 if (only_used
&& !df_regs_ever_live_p (regno
))
5881 if (only_arg
&& !FUNCTION_ARG_REGNO_P (regno
))
5884 /* Now this is a register that we might want to zero. */
5885 SET_HARD_REG_BIT (selected_hardregs
, regno
);
5888 if (hard_reg_set_empty_p (selected_hardregs
))
5891 /* Now that we have a hard register set that needs to be zeroed, pass it to
5892 target to generate zeroing sequence. */
5893 HARD_REG_SET zeroed_hardregs
;
5895 zeroed_hardregs
= targetm
.calls
.zero_call_used_regs (selected_hardregs
);
5896 rtx_insn
*seq
= get_insns ();
5900 /* Emit the memory blockage and register clobber asm volatile before
5901 the whole sequence. */
5903 expand_asm_reg_clobber_mem_blockage (zeroed_hardregs
);
5904 rtx_insn
*seq_barrier
= get_insns ();
5907 emit_insn_before (seq_barrier
, ret
);
5908 emit_insn_before (seq
, ret
);
5910 /* Update the data flow information. */
5911 crtl
->must_be_zero_on_return
|= zeroed_hardregs
;
5912 df_set_bb_dirty (EXIT_BLOCK_PTR_FOR_FN (cfun
));
5917 /* Return a sequence to be used as the epilogue for the current function,
5921 make_epilogue_seq (void)
5923 if (!targetm
.have_epilogue ())
5927 emit_note (NOTE_INSN_EPILOGUE_BEG
);
5928 rtx_insn
*seq
= targetm
.gen_epilogue ();
5930 emit_jump_insn (seq
);
5932 /* Retain a map of the epilogue insns. */
5933 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5934 set_insn_locations (seq
, epilogue_location
);
5937 rtx_insn
*returnjump
= get_last_insn ();
5940 if (JUMP_P (returnjump
))
5941 set_return_jump_label (returnjump
);
5947 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5948 this into place with notes indicating where the prologue ends and where
5949 the epilogue begins. Update the basic block information when possible.
5951 Notes on epilogue placement:
5952 There are several kinds of edges to the exit block:
5953 * a single fallthru edge from LAST_BB
5954 * possibly, edges from blocks containing sibcalls
5955 * possibly, fake edges from infinite loops
5957 The epilogue is always emitted on the fallthru edge from the last basic
5958 block in the function, LAST_BB, into the exit block.
5960 If LAST_BB is empty except for a label, it is the target of every
5961 other basic block in the function that ends in a return. If a
5962 target has a return or simple_return pattern (possibly with
5963 conditional variants), these basic blocks can be changed so that a
5964 return insn is emitted into them, and their target is adjusted to
5965 the real exit block.
5967 Notes on shrink wrapping: We implement a fairly conservative
5968 version of shrink-wrapping rather than the textbook one. We only
5969 generate a single prologue and a single epilogue. This is
5970 sufficient to catch a number of interesting cases involving early
5973 First, we identify the blocks that require the prologue to occur before
5974 them. These are the ones that modify a call-saved register, or reference
5975 any of the stack or frame pointer registers. To simplify things, we then
5976 mark everything reachable from these blocks as also requiring a prologue.
5977 This takes care of loops automatically, and avoids the need to examine
5978 whether MEMs reference the frame, since it is sufficient to check for
5979 occurrences of the stack or frame pointer.
5981 We then compute the set of blocks for which the need for a prologue
5982 is anticipatable (borrowing terminology from the shrink-wrapping
5983 description in Muchnick's book). These are the blocks which either
5984 require a prologue themselves, or those that have only successors
5985 where the prologue is anticipatable. The prologue needs to be
5986 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5987 is not. For the moment, we ensure that only one such edge exists.
5989 The epilogue is placed as described above, but we make a
5990 distinction between inserting return and simple_return patterns
5991 when modifying other blocks that end in a return. Blocks that end
5992 in a sibcall omit the sibcall_epilogue if the block is not in
5996 thread_prologue_and_epilogue_insns (void)
6000 /* Can't deal with multiple successors of the entry block at the
6001 moment. Function should always have at least one entry
6003 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun
)));
6005 edge entry_edge
= single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
6006 edge orig_entry_edge
= entry_edge
;
6008 rtx_insn
*split_prologue_seq
= make_split_prologue_seq ();
6009 rtx_insn
*prologue_seq
= make_prologue_seq ();
6010 rtx_insn
*epilogue_seq
= make_epilogue_seq ();
6012 /* Try to perform a kind of shrink-wrapping, making sure the
6013 prologue/epilogue is emitted only around those parts of the
6014 function that require it. */
6015 try_shrink_wrapping (&entry_edge
, prologue_seq
);
6017 /* If the target can handle splitting the prologue/epilogue into separate
6018 components, try to shrink-wrap these components separately. */
6019 try_shrink_wrapping_separate (entry_edge
->dest
);
6021 /* If that did anything for any component we now need the generate the
6022 "main" prologue again. Because some targets require some of these
6023 to be called in a specific order (i386 requires the split prologue
6024 to be first, for example), we create all three sequences again here.
6025 If this does not work for some target, that target should not enable
6026 separate shrink-wrapping. */
6027 if (crtl
->shrink_wrapped_separate
)
6029 split_prologue_seq
= make_split_prologue_seq ();
6030 prologue_seq
= make_prologue_seq ();
6031 epilogue_seq
= make_epilogue_seq ();
6034 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun
));
6036 /* A small fib -- epilogue is not yet completed, but we wish to re-use
6037 this marker for the splits of EH_RETURN patterns, and nothing else
6038 uses the flag in the meantime. */
6039 epilogue_completed
= 1;
6041 /* Find non-fallthru edges that end with EH_RETURN instructions. On
6042 some targets, these get split to a special version of the epilogue
6043 code. In order to be able to properly annotate these with unwind
6044 info, try to split them now. If we get a valid split, drop an
6045 EPILOGUE_BEG note and mark the insns as epilogue insns. */
6048 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6050 rtx_insn
*prev
, *last
, *trial
;
6052 if (e
->flags
& EDGE_FALLTHRU
)
6054 last
= BB_END (e
->src
);
6055 if (!eh_returnjump_p (last
))
6058 prev
= PREV_INSN (last
);
6059 trial
= try_split (PATTERN (last
), last
, 1);
6063 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
6064 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
6067 edge exit_fallthru_edge
= find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6069 if (exit_fallthru_edge
)
6073 insert_insn_on_edge (epilogue_seq
, exit_fallthru_edge
);
6074 commit_edge_insertions ();
6076 /* The epilogue insns we inserted may cause the exit edge to no longer
6078 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6080 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
6081 && returnjump_p (BB_END (e
->src
)))
6082 e
->flags
&= ~EDGE_FALLTHRU
;
6085 else if (next_active_insn (BB_END (exit_fallthru_edge
->src
)))
6087 /* We have a fall-through edge to the exit block, the source is not
6088 at the end of the function, and there will be an assembler epilogue
6089 at the end of the function.
6090 We can't use force_nonfallthru here, because that would try to
6091 use return. Inserting a jump 'by hand' is extremely messy, so
6092 we take advantage of cfg_layout_finalize using
6093 fixup_fallthru_exit_predecessor. */
6094 cfg_layout_initialize (0);
6096 FOR_EACH_BB_FN (cur_bb
, cfun
)
6097 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
6098 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
6099 cur_bb
->aux
= cur_bb
->next_bb
;
6100 cfg_layout_finalize ();
6104 /* Insert the prologue. */
6106 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
6108 if (split_prologue_seq
|| prologue_seq
)
6110 rtx_insn
*split_prologue_insn
= split_prologue_seq
;
6111 if (split_prologue_seq
)
6113 while (split_prologue_insn
&& !NONDEBUG_INSN_P (split_prologue_insn
))
6114 split_prologue_insn
= NEXT_INSN (split_prologue_insn
);
6115 insert_insn_on_edge (split_prologue_seq
, orig_entry_edge
);
6118 rtx_insn
*prologue_insn
= prologue_seq
;
6121 while (prologue_insn
&& !NONDEBUG_INSN_P (prologue_insn
))
6122 prologue_insn
= NEXT_INSN (prologue_insn
);
6123 insert_insn_on_edge (prologue_seq
, entry_edge
);
6126 commit_edge_insertions ();
6128 /* Look for basic blocks within the prologue insns. */
6129 if (split_prologue_insn
6130 && BLOCK_FOR_INSN (split_prologue_insn
) == NULL
)
6131 split_prologue_insn
= NULL
;
6133 && BLOCK_FOR_INSN (prologue_insn
) == NULL
)
6134 prologue_insn
= NULL
;
6135 if (split_prologue_insn
|| prologue_insn
)
6137 auto_sbitmap
blocks (last_basic_block_for_fn (cfun
));
6138 bitmap_clear (blocks
);
6139 if (split_prologue_insn
)
6140 bitmap_set_bit (blocks
,
6141 BLOCK_FOR_INSN (split_prologue_insn
)->index
);
6143 bitmap_set_bit (blocks
, BLOCK_FOR_INSN (prologue_insn
)->index
);
6144 find_many_sub_basic_blocks (blocks
);
6148 default_rtl_profile ();
6150 /* Emit sibling epilogues before any sibling call sites. */
6151 for (ei
= ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6152 (e
= ei_safe_edge (ei
));
6155 /* Skip those already handled, the ones that run without prologue. */
6156 if (e
->flags
& EDGE_IGNORE
)
6158 e
->flags
&= ~EDGE_IGNORE
;
6162 rtx_insn
*insn
= BB_END (e
->src
);
6164 if (!(CALL_P (insn
) && SIBLING_CALL_P (insn
)))
6167 if (rtx_insn
*ep_seq
= targetm
.gen_sibcall_epilogue ())
6170 emit_note (NOTE_INSN_EPILOGUE_BEG
);
6172 rtx_insn
*seq
= get_insns ();
6175 /* Retain a map of the epilogue insns. Used in life analysis to
6176 avoid getting rid of sibcall epilogue insns. Do this before we
6177 actually emit the sequence. */
6178 record_insns (seq
, NULL
, &epilogue_insn_hash
);
6179 set_insn_locations (seq
, epilogue_location
);
6181 emit_insn_before (seq
, insn
);
6187 rtx_insn
*insn
, *next
;
6189 /* Similarly, move any line notes that appear after the epilogue.
6190 There is no need, however, to be quite so anal about the existence
6191 of such a note. Also possibly move
6192 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6194 for (insn
= epilogue_seq
; insn
; insn
= next
)
6196 next
= NEXT_INSN (insn
);
6198 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
6199 reorder_insns (insn
, insn
, PREV_INSN (epilogue_seq
));
6203 /* Threading the prologue and epilogue changes the artificial refs
6204 in the entry and exit blocks. */
6205 epilogue_completed
= 1;
6206 df_update_entry_exit_and_calls ();
6209 /* Reposition the prologue-end and epilogue-begin notes after
6210 instruction scheduling. */
6213 reposition_prologue_and_epilogue_notes (void)
6215 if (!targetm
.have_prologue ()
6216 && !targetm
.have_epilogue ()
6217 && !targetm
.have_sibcall_epilogue ())
6220 /* Since the hash table is created on demand, the fact that it is
6221 non-null is a signal that it is non-empty. */
6222 if (prologue_insn_hash
!= NULL
)
6224 size_t len
= prologue_insn_hash
->elements ();
6225 rtx_insn
*insn
, *last
= NULL
, *note
= NULL
;
6227 /* Scan from the beginning until we reach the last prologue insn. */
6228 /* ??? While we do have the CFG intact, there are two problems:
6229 (1) The prologue can contain loops (typically probing the stack),
6230 which means that the end of the prologue isn't in the first bb.
6231 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6232 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
6236 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
6239 else if (contains (insn
, prologue_insn_hash
))
6251 /* Scan forward looking for the PROLOGUE_END note. It should
6252 be right at the beginning of the block, possibly with other
6253 insn notes that got moved there. */
6254 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
6257 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
6262 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6264 last
= NEXT_INSN (last
);
6265 reorder_insns (note
, note
, last
);
6269 if (epilogue_insn_hash
!= NULL
)
6274 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6276 rtx_insn
*insn
, *first
= NULL
, *note
= NULL
;
6277 basic_block bb
= e
->src
;
6279 /* Scan from the beginning until we reach the first epilogue insn. */
6280 FOR_BB_INSNS (bb
, insn
)
6284 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
6291 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
6301 /* If the function has a single basic block, and no real
6302 epilogue insns (e.g. sibcall with no cleanup), the
6303 epilogue note can get scheduled before the prologue
6304 note. If we have frame related prologue insns, having
6305 them scanned during the epilogue will result in a crash.
6306 In this case re-order the epilogue note to just before
6307 the last insn in the block. */
6309 first
= BB_END (bb
);
6311 if (PREV_INSN (first
) != note
)
6312 reorder_insns (note
, note
, PREV_INSN (first
));
6318 /* Returns the name of function declared by FNDECL. */
6320 fndecl_name (tree fndecl
)
6324 return lang_hooks
.decl_printable_name (fndecl
, 1);
6327 /* Returns the name of function FN. */
6329 function_name (struct function
*fn
)
6331 tree fndecl
= (fn
== NULL
) ? NULL
: fn
->decl
;
6332 return fndecl_name (fndecl
);
6335 /* Returns the name of the current function. */
6337 current_function_name (void)
6339 return function_name (cfun
);
6344 rest_of_handle_check_leaf_regs (void)
6346 #ifdef LEAF_REGISTERS
6347 crtl
->uses_only_leaf_regs
6348 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
6353 /* Insert a TYPE into the used types hash table of CFUN. */
6356 used_types_insert_helper (tree type
, struct function
*func
)
6358 if (type
!= NULL
&& func
!= NULL
)
6360 if (func
->used_types_hash
== NULL
)
6361 func
->used_types_hash
= hash_set
<tree
>::create_ggc (37);
6363 func
->used_types_hash
->add (type
);
6367 /* Given a type, insert it into the used hash table in cfun. */
6369 used_types_insert (tree t
)
6371 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
6376 if (TREE_CODE (t
) == ERROR_MARK
)
6378 if (TYPE_NAME (t
) == NULL_TREE
6379 || TYPE_NAME (t
) == TYPE_NAME (TYPE_MAIN_VARIANT (t
)))
6380 t
= TYPE_MAIN_VARIANT (t
);
6381 if (debug_info_level
> DINFO_LEVEL_NONE
)
6384 used_types_insert_helper (t
, cfun
);
6387 /* So this might be a type referenced by a global variable.
6388 Record that type so that we can later decide to emit its
6389 debug information. */
6390 vec_safe_push (types_used_by_cur_var_decl
, t
);
6395 /* Helper to Hash a struct types_used_by_vars_entry. */
6398 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
6400 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
6402 return iterative_hash_object (entry
->type
,
6403 iterative_hash_object (entry
->var_decl
, 0));
6406 /* Hash function of the types_used_by_vars_entry hash table. */
6409 used_type_hasher::hash (types_used_by_vars_entry
*entry
)
6411 return hash_types_used_by_vars_entry (entry
);
6414 /*Equality function of the types_used_by_vars_entry hash table. */
6417 used_type_hasher::equal (types_used_by_vars_entry
*e1
,
6418 types_used_by_vars_entry
*e2
)
6420 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
6423 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6426 types_used_by_var_decl_insert (tree type
, tree var_decl
)
6428 if (type
!= NULL
&& var_decl
!= NULL
)
6430 types_used_by_vars_entry
**slot
;
6431 struct types_used_by_vars_entry e
;
6432 e
.var_decl
= var_decl
;
6434 if (types_used_by_vars_hash
== NULL
)
6435 types_used_by_vars_hash
6436 = hash_table
<used_type_hasher
>::create_ggc (37);
6438 slot
= types_used_by_vars_hash
->find_slot (&e
, INSERT
);
6441 struct types_used_by_vars_entry
*entry
;
6442 entry
= ggc_alloc
<types_used_by_vars_entry
> ();
6444 entry
->var_decl
= var_decl
;
6452 const pass_data pass_data_leaf_regs
=
6454 RTL_PASS
, /* type */
6455 "*leaf_regs", /* name */
6456 OPTGROUP_NONE
, /* optinfo_flags */
6457 TV_NONE
, /* tv_id */
6458 0, /* properties_required */
6459 0, /* properties_provided */
6460 0, /* properties_destroyed */
6461 0, /* todo_flags_start */
6462 0, /* todo_flags_finish */
6465 class pass_leaf_regs
: public rtl_opt_pass
6468 pass_leaf_regs (gcc::context
*ctxt
)
6469 : rtl_opt_pass (pass_data_leaf_regs
, ctxt
)
6472 /* opt_pass methods: */
6473 virtual unsigned int execute (function
*)
6475 return rest_of_handle_check_leaf_regs ();
6478 }; // class pass_leaf_regs
6483 make_pass_leaf_regs (gcc::context
*ctxt
)
6485 return new pass_leaf_regs (ctxt
);
6489 rest_of_handle_thread_prologue_and_epilogue (void)
6491 /* prepare_shrink_wrap is sensitive to the block structure of the control
6492 flow graph, so clean it up first. */
6496 /* On some machines, the prologue and epilogue code, or parts thereof,
6497 can be represented as RTL. Doing so lets us schedule insns between
6498 it and the rest of the code and also allows delayed branch
6499 scheduling to operate in the epilogue. */
6500 thread_prologue_and_epilogue_insns ();
6502 /* Some non-cold blocks may now be only reachable from cold blocks.
6504 fixup_partitions ();
6506 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6508 cleanup_cfg (optimize
? CLEANUP_EXPENSIVE
: 0);
6510 /* The stack usage info is finalized during prologue expansion. */
6511 if (flag_stack_usage_info
|| flag_callgraph_info
)
6512 output_stack_usage ();
6517 /* Record a final call to CALLEE at LOCATION. */
6520 record_final_call (tree callee
, location_t location
)
6522 struct callinfo_callee datum
= { location
, callee
};
6523 vec_safe_push (cfun
->su
->callees
, datum
);
6526 /* Record a dynamic allocation made for DECL_OR_EXP. */
6529 record_dynamic_alloc (tree decl_or_exp
)
6531 struct callinfo_dalloc datum
;
6533 if (DECL_P (decl_or_exp
))
6535 datum
.location
= DECL_SOURCE_LOCATION (decl_or_exp
);
6536 const char *name
= lang_hooks
.decl_printable_name (decl_or_exp
, 2);
6537 const char *dot
= strrchr (name
, '.');
6540 datum
.name
= ggc_strdup (name
);
6544 datum
.location
= EXPR_LOCATION (decl_or_exp
);
6548 vec_safe_push (cfun
->su
->dallocs
, datum
);
6553 const pass_data pass_data_thread_prologue_and_epilogue
=
6555 RTL_PASS
, /* type */
6556 "pro_and_epilogue", /* name */
6557 OPTGROUP_NONE
, /* optinfo_flags */
6558 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
6559 0, /* properties_required */
6560 0, /* properties_provided */
6561 0, /* properties_destroyed */
6562 0, /* todo_flags_start */
6563 ( TODO_df_verify
| TODO_df_finish
), /* todo_flags_finish */
6566 class pass_thread_prologue_and_epilogue
: public rtl_opt_pass
6569 pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
6570 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue
, ctxt
)
6573 /* opt_pass methods: */
6574 virtual unsigned int execute (function
*)
6576 return rest_of_handle_thread_prologue_and_epilogue ();
6579 }; // class pass_thread_prologue_and_epilogue
6584 make_pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
6586 return new pass_thread_prologue_and_epilogue (ctxt
);
6591 const pass_data pass_data_zero_call_used_regs
=
6593 RTL_PASS
, /* type */
6594 "zero_call_used_regs", /* name */
6595 OPTGROUP_NONE
, /* optinfo_flags */
6596 TV_NONE
, /* tv_id */
6597 0, /* properties_required */
6598 0, /* properties_provided */
6599 0, /* properties_destroyed */
6600 0, /* todo_flags_start */
6601 0, /* todo_flags_finish */
6604 class pass_zero_call_used_regs
: public rtl_opt_pass
6607 pass_zero_call_used_regs (gcc::context
*ctxt
)
6608 : rtl_opt_pass (pass_data_zero_call_used_regs
, ctxt
)
6611 /* opt_pass methods: */
6612 virtual unsigned int execute (function
*);
6614 }; // class pass_zero_call_used_regs
6617 pass_zero_call_used_regs::execute (function
*fun
)
6619 using namespace zero_regs_flags
;
6620 unsigned int zero_regs_type
= UNSET
;
6622 tree attr_zero_regs
= lookup_attribute ("zero_call_used_regs",
6623 DECL_ATTRIBUTES (fun
->decl
));
6625 /* Get the type of zero_call_used_regs from function attribute.
6626 We have filtered out invalid attribute values already at this point. */
6629 /* The TREE_VALUE of an attribute is a TREE_LIST whose TREE_VALUE
6630 is the attribute argument's value. */
6631 attr_zero_regs
= TREE_VALUE (attr_zero_regs
);
6632 gcc_assert (TREE_CODE (attr_zero_regs
) == TREE_LIST
);
6633 attr_zero_regs
= TREE_VALUE (attr_zero_regs
);
6634 gcc_assert (TREE_CODE (attr_zero_regs
) == STRING_CST
);
6636 for (unsigned int i
= 0; zero_call_used_regs_opts
[i
].name
!= NULL
; ++i
)
6637 if (strcmp (TREE_STRING_POINTER (attr_zero_regs
),
6638 zero_call_used_regs_opts
[i
].name
) == 0)
6640 zero_regs_type
= zero_call_used_regs_opts
[i
].flag
;
6645 if (!zero_regs_type
)
6646 zero_regs_type
= flag_zero_call_used_regs
;
6648 /* No need to zero call-used-regs when no user request is present. */
6649 if (!(zero_regs_type
& ENABLED
))
6655 /* This pass needs data flow information. */
6658 /* Iterate over the function's return instructions and insert any
6659 register zeroing required by the -fzero-call-used-regs command-line
6660 option or the "zero_call_used_regs" function attribute. */
6661 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6663 rtx_insn
*insn
= BB_END (e
->src
);
6664 if (JUMP_P (insn
) && ANY_RETURN_P (JUMP_LABEL (insn
)))
6665 gen_call_used_regs_seq (insn
, zero_regs_type
);
6674 make_pass_zero_call_used_regs (gcc::context
*ctxt
)
6676 return new pass_zero_call_used_regs (ctxt
);
6679 /* If CONSTRAINT is a matching constraint, then return its number.
6680 Otherwise, return -1. */
6683 matching_constraint_num (const char *constraint
)
6685 if (*constraint
== '%')
6688 if (IN_RANGE (*constraint
, '0', '9'))
6689 return strtoul (constraint
, NULL
, 10);
6694 /* This mini-pass fixes fall-out from SSA in asm statements that have
6695 in-out constraints. Say you start with
6698 asm ("": "+mr" (inout));
6701 which is transformed very early to use explicit output and match operands:
6704 asm ("": "=mr" (inout) : "0" (inout));
6707 Or, after SSA and copyprop,
6709 asm ("": "=mr" (inout_2) : "0" (inout_1));
6712 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6713 they represent two separate values, so they will get different pseudo
6714 registers during expansion. Then, since the two operands need to match
6715 per the constraints, but use different pseudo registers, reload can
6716 only register a reload for these operands. But reloads can only be
6717 satisfied by hardregs, not by memory, so we need a register for this
6718 reload, just because we are presented with non-matching operands.
6719 So, even though we allow memory for this operand, no memory can be
6720 used for it, just because the two operands don't match. This can
6721 cause reload failures on register-starved targets.
6723 So it's a symptom of reload not being able to use memory for reloads
6724 or, alternatively it's also a symptom of both operands not coming into
6725 reload as matching (in which case the pseudo could go to memory just
6726 fine, as the alternative allows it, and no reload would be necessary).
6727 We fix the latter problem here, by transforming
6729 asm ("": "=mr" (inout_2) : "0" (inout_1));
6734 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6737 match_asm_constraints_1 (rtx_insn
*insn
, rtx
*p_sets
, int noutputs
)
6740 bool changed
= false;
6741 rtx op
= SET_SRC (p_sets
[0]);
6742 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
6743 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
6744 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
6746 memset (output_matched
, 0, noutputs
* sizeof (bool));
6747 for (i
= 0; i
< ninputs
; i
++)
6751 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
6754 match
= matching_constraint_num (constraint
);
6758 gcc_assert (match
< noutputs
);
6759 output
= SET_DEST (p_sets
[match
]);
6760 input
= RTVEC_ELT (inputs
, i
);
6761 /* Only do the transformation for pseudos. */
6762 if (! REG_P (output
)
6763 || rtx_equal_p (output
, input
)
6764 || !(REG_P (input
) || SUBREG_P (input
)
6765 || MEM_P (input
) || CONSTANT_P (input
))
6766 || !general_operand (input
, GET_MODE (output
)))
6769 /* We can't do anything if the output is also used as input,
6770 as we're going to overwrite it. */
6771 for (j
= 0; j
< ninputs
; j
++)
6772 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
6777 /* Avoid changing the same input several times. For
6778 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6779 only change it once (to out1), rather than changing it
6780 first to out1 and afterwards to out2. */
6783 for (j
= 0; j
< noutputs
; j
++)
6784 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
6789 output_matched
[match
] = true;
6792 emit_move_insn (output
, copy_rtx (input
));
6793 insns
= get_insns ();
6795 emit_insn_before (insns
, insn
);
6797 constraint
= ASM_OPERANDS_OUTPUT_CONSTRAINT(SET_SRC(p_sets
[match
]));
6798 bool early_clobber_p
= strchr (constraint
, '&') != NULL
;
6800 /* Now replace all mentions of the input with output. We can't
6801 just replace the occurrence in inputs[i], as the register might
6802 also be used in some other input (or even in an address of an
6803 output), which would mean possibly increasing the number of
6804 inputs by one (namely 'output' in addition), which might pose
6805 a too complicated problem for reload to solve. E.g. this situation:
6807 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6809 Here 'input' is used in two occurrences as input (once for the
6810 input operand, once for the address in the second output operand).
6811 If we would replace only the occurrence of the input operand (to
6812 make the matching) we would be left with this:
6815 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6817 Now we suddenly have two different input values (containing the same
6818 value, but different pseudos) where we formerly had only one.
6819 With more complicated asms this might lead to reload failures
6820 which wouldn't have happen without this pass. So, iterate over
6821 all operands and replace all occurrences of the register used.
6823 However, if one or more of the 'input' uses have a non-matching
6824 constraint and the matched output operand is an early clobber
6825 operand, then do not replace the input operand, since by definition
6826 it conflicts with the output operand and cannot share the same
6827 register. See PR89313 for details. */
6829 for (j
= 0; j
< noutputs
; j
++)
6830 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
6831 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
6832 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
6834 for (j
= 0; j
< ninputs
; j
++)
6835 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
6837 if (!early_clobber_p
6838 || match
== matching_constraint_num
6839 (ASM_OPERANDS_INPUT_CONSTRAINT (op
, j
)))
6840 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
6848 df_insn_rescan (insn
);
6851 /* Add the decl D to the local_decls list of FUN. */
6854 add_local_decl (struct function
*fun
, tree d
)
6856 gcc_assert (VAR_P (d
));
6857 vec_safe_push (fun
->local_decls
, d
);
6862 const pass_data pass_data_match_asm_constraints
=
6864 RTL_PASS
, /* type */
6865 "asmcons", /* name */
6866 OPTGROUP_NONE
, /* optinfo_flags */
6867 TV_NONE
, /* tv_id */
6868 0, /* properties_required */
6869 0, /* properties_provided */
6870 0, /* properties_destroyed */
6871 0, /* todo_flags_start */
6872 0, /* todo_flags_finish */
6875 class pass_match_asm_constraints
: public rtl_opt_pass
6878 pass_match_asm_constraints (gcc::context
*ctxt
)
6879 : rtl_opt_pass (pass_data_match_asm_constraints
, ctxt
)
6882 /* opt_pass methods: */
6883 virtual unsigned int execute (function
*);
6885 }; // class pass_match_asm_constraints
6888 pass_match_asm_constraints::execute (function
*fun
)
6895 if (!crtl
->has_asm_statement
)
6898 df_set_flags (DF_DEFER_INSN_RESCAN
);
6899 FOR_EACH_BB_FN (bb
, fun
)
6901 FOR_BB_INSNS (bb
, insn
)
6906 pat
= PATTERN (insn
);
6907 if (GET_CODE (pat
) == PARALLEL
)
6908 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
6909 else if (GET_CODE (pat
) == SET
)
6910 p_sets
= &PATTERN (insn
), noutputs
= 1;
6914 if (GET_CODE (*p_sets
) == SET
6915 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
6916 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
6920 return TODO_df_finish
;
6926 make_pass_match_asm_constraints (gcc::context
*ctxt
)
6928 return new pass_match_asm_constraints (ctxt
);
6932 #include "gt-function.h"