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"
52 #include "rtl-error.h"
54 #include "fold-const.h"
55 #include "stor-layout.h"
62 #include "optabs-tree.h"
64 #include "langhooks.h"
65 #include "common/common-target.h"
67 #include "tree-pass.h"
71 #include "cfgcleanup.h"
72 #include "cfgexpand.h"
73 #include "shrink-wrap.h"
78 #include "stringpool.h"
82 #include "function-abi.h"
84 /* So we can assign to cfun in this file. */
87 #ifndef STACK_ALIGNMENT_NEEDED
88 #define STACK_ALIGNMENT_NEEDED 1
91 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
93 /* Round a value to the lowest integer less than it that is a multiple of
94 the required alignment. Avoid using division in case the value is
95 negative. Assume the alignment is a power of two. */
96 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
98 /* Similar, but round to the next highest integer that meets the
100 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
102 /* Nonzero once virtual register instantiation has been done.
103 assign_stack_local uses frame_pointer_rtx when this is nonzero.
104 calls.c:emit_library_call_value_1 uses it to set up
105 post-instantiation libcalls. */
106 int virtuals_instantiated
;
108 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
109 static GTY(()) int funcdef_no
;
111 /* These variables hold pointers to functions to create and destroy
112 target specific, per-function data structures. */
113 struct machine_function
* (*init_machine_status
) (void);
115 /* The currently compiled function. */
116 struct function
*cfun
= 0;
118 /* These hashes record the prologue and epilogue insns. */
120 struct insn_cache_hasher
: ggc_cache_ptr_hash
<rtx_def
>
122 static hashval_t
hash (rtx x
) { return htab_hash_pointer (x
); }
123 static bool equal (rtx a
, rtx b
) { return a
== b
; }
127 hash_table
<insn_cache_hasher
> *prologue_insn_hash
;
129 hash_table
<insn_cache_hasher
> *epilogue_insn_hash
;
132 hash_table
<used_type_hasher
> *types_used_by_vars_hash
= NULL
;
133 vec
<tree
, va_gc
> *types_used_by_cur_var_decl
;
135 /* Forward declarations. */
137 static class temp_slot
*find_temp_slot_from_address (rtx
);
138 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
139 static void pad_below (struct args_size
*, machine_mode
, tree
);
140 static void reorder_blocks_1 (rtx_insn
*, tree
, vec
<tree
> *);
141 static int all_blocks (tree
, tree
*);
142 static tree
*get_block_vector (tree
, int *);
143 extern tree
debug_find_var_in_block_tree (tree
, tree
);
144 /* We always define `record_insns' even if it's not used so that we
145 can always export `prologue_epilogue_contains'. */
146 static void record_insns (rtx_insn
*, rtx
, hash_table
<insn_cache_hasher
> **)
148 static bool contains (const rtx_insn
*, hash_table
<insn_cache_hasher
> *);
149 static void prepare_function_start (void);
150 static void do_clobber_return_reg (rtx
, void *);
151 static void do_use_return_reg (rtx
, void *);
154 /* Stack of nested functions. */
155 /* Keep track of the cfun stack. */
157 static vec
<function
*> function_context_stack
;
159 /* Save the current context for compilation of a nested function.
160 This is called from language-specific code. */
163 push_function_context (void)
166 allocate_struct_function (NULL
, false);
168 function_context_stack
.safe_push (cfun
);
172 /* Restore the last saved context, at the end of a nested function.
173 This function is called from language-specific code. */
176 pop_function_context (void)
178 struct function
*p
= function_context_stack
.pop ();
180 current_function_decl
= p
->decl
;
182 /* Reset variables that have known state during rtx generation. */
183 virtuals_instantiated
= 0;
184 generating_concat_p
= 1;
187 /* Clear out all parts of the state in F that can safely be discarded
188 after the function has been parsed, but not compiled, to let
189 garbage collection reclaim the memory. */
192 free_after_parsing (struct function
*f
)
197 /* Clear out all parts of the state in F that can safely be discarded
198 after the function has been compiled, to let garbage collection
199 reclaim the memory. */
202 free_after_compilation (struct function
*f
)
204 prologue_insn_hash
= NULL
;
205 epilogue_insn_hash
= NULL
;
207 free (crtl
->emit
.regno_pointer_align
);
209 memset (crtl
, 0, sizeof (struct rtl_data
));
213 f
->curr_properties
&= ~PROP_cfg
;
215 regno_reg_rtx
= NULL
;
218 /* Return size needed for stack frame based on slots so far allocated.
219 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
220 the caller may have to do that. */
223 get_frame_size (void)
225 if (FRAME_GROWS_DOWNWARD
)
226 return -frame_offset
;
231 /* Issue an error message and return TRUE if frame OFFSET overflows in
232 the signed target pointer arithmetics for function FUNC. Otherwise
236 frame_offset_overflow (poly_int64 offset
, tree func
)
238 poly_uint64 size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
239 unsigned HOST_WIDE_INT limit
240 = ((HOST_WIDE_INT_1U
<< (GET_MODE_BITSIZE (Pmode
) - 1))
241 /* Leave room for the fixed part of the frame. */
242 - 64 * UNITS_PER_WORD
);
244 if (!coeffs_in_range_p (size
, 0U, limit
))
246 unsigned HOST_WIDE_INT hwisize
;
247 if (size
.is_constant (&hwisize
))
248 error_at (DECL_SOURCE_LOCATION (func
),
249 "total size of local objects %wu exceeds maximum %wu",
252 error_at (DECL_SOURCE_LOCATION (func
),
253 "total size of local objects exceeds maximum %wu",
261 /* Return the minimum spill slot alignment for a register of mode MODE. */
264 spill_slot_alignment (machine_mode mode ATTRIBUTE_UNUSED
)
266 return STACK_SLOT_ALIGNMENT (NULL_TREE
, mode
, GET_MODE_ALIGNMENT (mode
));
269 /* Return stack slot alignment in bits for TYPE and MODE. */
272 get_stack_local_alignment (tree type
, machine_mode mode
)
274 unsigned int alignment
;
277 alignment
= BIGGEST_ALIGNMENT
;
279 alignment
= GET_MODE_ALIGNMENT (mode
);
281 /* Allow the frond-end to (possibly) increase the alignment of this
284 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
286 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
289 /* Determine whether it is possible to fit a stack slot of size SIZE and
290 alignment ALIGNMENT into an area in the stack frame that starts at
291 frame offset START and has a length of LENGTH. If so, store the frame
292 offset to be used for the stack slot in *POFFSET and return true;
293 return false otherwise. This function will extend the frame size when
294 given a start/length pair that lies at the end of the frame. */
297 try_fit_stack_local (poly_int64 start
, poly_int64 length
,
298 poly_int64 size
, unsigned int alignment
,
299 poly_int64_pod
*poffset
)
301 poly_int64 this_frame_offset
;
302 int frame_off
, frame_alignment
, frame_phase
;
304 /* Calculate how many bytes the start of local variables is off from
306 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
307 frame_off
= targetm
.starting_frame_offset () % frame_alignment
;
308 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
310 /* Round the frame offset to the specified alignment. */
312 if (FRAME_GROWS_DOWNWARD
)
314 = (aligned_lower_bound (start
+ length
- size
- frame_phase
, alignment
)
318 = aligned_upper_bound (start
- frame_phase
, alignment
) + frame_phase
;
320 /* See if it fits. If this space is at the edge of the frame,
321 consider extending the frame to make it fit. Our caller relies on
322 this when allocating a new slot. */
323 if (maybe_lt (this_frame_offset
, start
))
325 if (known_eq (frame_offset
, start
))
326 frame_offset
= this_frame_offset
;
330 else if (maybe_gt (this_frame_offset
+ size
, start
+ length
))
332 if (known_eq (frame_offset
, start
+ length
))
333 frame_offset
= this_frame_offset
+ size
;
338 *poffset
= this_frame_offset
;
342 /* Create a new frame_space structure describing free space in the stack
343 frame beginning at START and ending at END, and chain it into the
344 function's frame_space_list. */
347 add_frame_space (poly_int64 start
, poly_int64 end
)
349 class frame_space
*space
= ggc_alloc
<frame_space
> ();
350 space
->next
= crtl
->frame_space_list
;
351 crtl
->frame_space_list
= space
;
352 space
->start
= start
;
353 space
->length
= end
- start
;
356 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
357 with machine mode MODE.
359 ALIGN controls the amount of alignment for the address of the slot:
360 0 means according to MODE,
361 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
362 -2 means use BITS_PER_UNIT,
363 positive specifies alignment boundary in bits.
365 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
366 alignment and ASLK_RECORD_PAD bit set if we should remember
367 extra space we allocated for alignment purposes. When we are
368 called from assign_stack_temp_for_type, it is not set so we don't
369 track the same stack slot in two independent lists.
371 We do not round to stack_boundary here. */
374 assign_stack_local_1 (machine_mode mode
, poly_int64 size
,
378 poly_int64 bigend_correction
= 0;
379 poly_int64 slot_offset
= 0, old_frame_offset
;
380 unsigned int alignment
, alignment_in_bits
;
384 alignment
= get_stack_local_alignment (NULL
, mode
);
385 alignment
/= BITS_PER_UNIT
;
387 else if (align
== -1)
389 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
390 size
= aligned_upper_bound (size
, alignment
);
392 else if (align
== -2)
393 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
395 alignment
= align
/ BITS_PER_UNIT
;
397 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
399 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
400 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
402 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
403 alignment
= MAX_SUPPORTED_STACK_ALIGNMENT
/ BITS_PER_UNIT
;
406 if (SUPPORTS_STACK_ALIGNMENT
)
408 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
410 if (!crtl
->stack_realign_processed
)
411 crtl
->stack_alignment_estimated
= alignment_in_bits
;
414 /* If stack is realigned and stack alignment value
415 hasn't been finalized, it is OK not to increase
416 stack_alignment_estimated. The bigger alignment
417 requirement is recorded in stack_alignment_needed
419 gcc_assert (!crtl
->stack_realign_finalized
);
420 if (!crtl
->stack_realign_needed
)
422 /* It is OK to reduce the alignment as long as the
423 requested size is 0 or the estimated stack
424 alignment >= mode alignment. */
425 gcc_assert ((kind
& ASLK_REDUCE_ALIGN
)
426 || known_eq (size
, 0)
427 || (crtl
->stack_alignment_estimated
428 >= GET_MODE_ALIGNMENT (mode
)));
429 alignment_in_bits
= crtl
->stack_alignment_estimated
;
430 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
436 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
437 crtl
->stack_alignment_needed
= alignment_in_bits
;
438 if (crtl
->max_used_stack_slot_alignment
< alignment_in_bits
)
439 crtl
->max_used_stack_slot_alignment
= alignment_in_bits
;
441 if (mode
!= BLKmode
|| maybe_ne (size
, 0))
443 if (kind
& ASLK_RECORD_PAD
)
445 class frame_space
**psp
;
447 for (psp
= &crtl
->frame_space_list
; *psp
; psp
= &(*psp
)->next
)
449 class frame_space
*space
= *psp
;
450 if (!try_fit_stack_local (space
->start
, space
->length
, size
,
451 alignment
, &slot_offset
))
454 if (known_gt (slot_offset
, space
->start
))
455 add_frame_space (space
->start
, slot_offset
);
456 if (known_lt (slot_offset
+ size
, space
->start
+ space
->length
))
457 add_frame_space (slot_offset
+ size
,
458 space
->start
+ space
->length
);
463 else if (!STACK_ALIGNMENT_NEEDED
)
465 slot_offset
= frame_offset
;
469 old_frame_offset
= frame_offset
;
471 if (FRAME_GROWS_DOWNWARD
)
473 frame_offset
-= size
;
474 try_fit_stack_local (frame_offset
, size
, size
, alignment
, &slot_offset
);
476 if (kind
& ASLK_RECORD_PAD
)
478 if (known_gt (slot_offset
, frame_offset
))
479 add_frame_space (frame_offset
, slot_offset
);
480 if (known_lt (slot_offset
+ size
, old_frame_offset
))
481 add_frame_space (slot_offset
+ size
, old_frame_offset
);
486 frame_offset
+= size
;
487 try_fit_stack_local (old_frame_offset
, size
, size
, alignment
, &slot_offset
);
489 if (kind
& ASLK_RECORD_PAD
)
491 if (known_gt (slot_offset
, old_frame_offset
))
492 add_frame_space (old_frame_offset
, slot_offset
);
493 if (known_lt (slot_offset
+ size
, frame_offset
))
494 add_frame_space (slot_offset
+ size
, frame_offset
);
499 /* On a big-endian machine, if we are allocating more space than we will use,
500 use the least significant bytes of those that are allocated. */
503 /* The slot size can sometimes be smaller than the mode size;
504 e.g. the rs6000 port allocates slots with a vector mode
505 that have the size of only one element. However, the slot
506 size must always be ordered wrt to the mode size, in the
507 same way as for a subreg. */
508 gcc_checking_assert (ordered_p (GET_MODE_SIZE (mode
), size
));
509 if (BYTES_BIG_ENDIAN
&& maybe_lt (GET_MODE_SIZE (mode
), size
))
510 bigend_correction
= size
- GET_MODE_SIZE (mode
);
513 /* If we have already instantiated virtual registers, return the actual
514 address relative to the frame pointer. */
515 if (virtuals_instantiated
)
516 addr
= plus_constant (Pmode
, frame_pointer_rtx
,
518 (slot_offset
+ bigend_correction
519 + targetm
.starting_frame_offset (), Pmode
));
521 addr
= plus_constant (Pmode
, virtual_stack_vars_rtx
,
523 (slot_offset
+ bigend_correction
,
526 x
= gen_rtx_MEM (mode
, addr
);
527 set_mem_align (x
, alignment_in_bits
);
528 MEM_NOTRAP_P (x
) = 1;
530 vec_safe_push (stack_slot_list
, x
);
532 if (frame_offset_overflow (frame_offset
, current_function_decl
))
538 /* Wrap up assign_stack_local_1 with last parameter as false. */
541 assign_stack_local (machine_mode mode
, poly_int64 size
, int align
)
543 return assign_stack_local_1 (mode
, size
, align
, ASLK_RECORD_PAD
);
546 /* In order to evaluate some expressions, such as function calls returning
547 structures in memory, we need to temporarily allocate stack locations.
548 We record each allocated temporary in the following structure.
550 Associated with each temporary slot is a nesting level. When we pop up
551 one level, all temporaries associated with the previous level are freed.
552 Normally, all temporaries are freed after the execution of the statement
553 in which they were created. However, if we are inside a ({...}) grouping,
554 the result may be in a temporary and hence must be preserved. If the
555 result could be in a temporary, we preserve it if we can determine which
556 one it is in. If we cannot determine which temporary may contain the
557 result, all temporaries are preserved. A temporary is preserved by
558 pretending it was allocated at the previous nesting level. */
560 class GTY(()) temp_slot
{
562 /* Points to next temporary slot. */
563 class temp_slot
*next
;
564 /* Points to previous temporary slot. */
565 class temp_slot
*prev
;
566 /* The rtx to used to reference the slot. */
568 /* The size, in units, of the slot. */
570 /* The type of the object in the slot, or zero if it doesn't correspond
571 to a type. We use this to determine whether a slot can be reused.
572 It can be reused if objects of the type of the new slot will always
573 conflict with objects of the type of the old slot. */
575 /* The alignment (in bits) of the slot. */
577 /* Nonzero if this temporary is currently in use. */
579 /* Nesting level at which this slot is being used. */
581 /* The offset of the slot from the frame_pointer, including extra space
582 for alignment. This info is for combine_temp_slots. */
583 poly_int64 base_offset
;
584 /* The size of the slot, including extra space for alignment. This
585 info is for combine_temp_slots. */
586 poly_int64 full_size
;
589 /* Entry for the below hash table. */
590 struct GTY((for_user
)) temp_slot_address_entry
{
593 class temp_slot
*temp_slot
;
596 struct temp_address_hasher
: ggc_ptr_hash
<temp_slot_address_entry
>
598 static hashval_t
hash (temp_slot_address_entry
*);
599 static bool equal (temp_slot_address_entry
*, temp_slot_address_entry
*);
602 /* A table of addresses that represent a stack slot. The table is a mapping
603 from address RTXen to a temp slot. */
604 static GTY(()) hash_table
<temp_address_hasher
> *temp_slot_address_table
;
605 static size_t n_temp_slots_in_use
;
607 /* Removes temporary slot TEMP from LIST. */
610 cut_slot_from_list (class temp_slot
*temp
, class temp_slot
**list
)
613 temp
->next
->prev
= temp
->prev
;
615 temp
->prev
->next
= temp
->next
;
619 temp
->prev
= temp
->next
= NULL
;
622 /* Inserts temporary slot TEMP to LIST. */
625 insert_slot_to_list (class temp_slot
*temp
, class temp_slot
**list
)
629 (*list
)->prev
= temp
;
634 /* Returns the list of used temp slots at LEVEL. */
636 static class temp_slot
**
637 temp_slots_at_level (int level
)
639 if (level
>= (int) vec_safe_length (used_temp_slots
))
640 vec_safe_grow_cleared (used_temp_slots
, level
+ 1, true);
642 return &(*used_temp_slots
)[level
];
645 /* Returns the maximal temporary slot level. */
648 max_slot_level (void)
650 if (!used_temp_slots
)
653 return used_temp_slots
->length () - 1;
656 /* Moves temporary slot TEMP to LEVEL. */
659 move_slot_to_level (class temp_slot
*temp
, int level
)
661 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
662 insert_slot_to_list (temp
, temp_slots_at_level (level
));
666 /* Make temporary slot TEMP available. */
669 make_slot_available (class temp_slot
*temp
)
671 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
672 insert_slot_to_list (temp
, &avail_temp_slots
);
675 n_temp_slots_in_use
--;
678 /* Compute the hash value for an address -> temp slot mapping.
679 The value is cached on the mapping entry. */
681 temp_slot_address_compute_hash (struct temp_slot_address_entry
*t
)
683 int do_not_record
= 0;
684 return hash_rtx (t
->address
, GET_MODE (t
->address
),
685 &do_not_record
, NULL
, false);
688 /* Return the hash value for an address -> temp slot mapping. */
690 temp_address_hasher::hash (temp_slot_address_entry
*t
)
695 /* Compare two address -> temp slot mapping entries. */
697 temp_address_hasher::equal (temp_slot_address_entry
*t1
,
698 temp_slot_address_entry
*t2
)
700 return exp_equiv_p (t1
->address
, t2
->address
, 0, true);
703 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
705 insert_temp_slot_address (rtx address
, class temp_slot
*temp_slot
)
707 struct temp_slot_address_entry
*t
= ggc_alloc
<temp_slot_address_entry
> ();
708 t
->address
= copy_rtx (address
);
709 t
->temp_slot
= temp_slot
;
710 t
->hash
= temp_slot_address_compute_hash (t
);
711 *temp_slot_address_table
->find_slot_with_hash (t
, t
->hash
, INSERT
) = t
;
714 /* Remove an address -> temp slot mapping entry if the temp slot is
715 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
717 remove_unused_temp_slot_addresses_1 (temp_slot_address_entry
**slot
, void *)
719 const struct temp_slot_address_entry
*t
= *slot
;
720 if (! t
->temp_slot
->in_use
)
721 temp_slot_address_table
->clear_slot (slot
);
725 /* Remove all mappings of addresses to unused temp slots. */
727 remove_unused_temp_slot_addresses (void)
729 /* Use quicker clearing if there aren't any active temp slots. */
730 if (n_temp_slots_in_use
)
731 temp_slot_address_table
->traverse
732 <void *, remove_unused_temp_slot_addresses_1
> (NULL
);
734 temp_slot_address_table
->empty ();
737 /* Find the temp slot corresponding to the object at address X. */
739 static class temp_slot
*
740 find_temp_slot_from_address (rtx x
)
743 struct temp_slot_address_entry tmp
, *t
;
745 /* First try the easy way:
746 See if X exists in the address -> temp slot mapping. */
748 tmp
.temp_slot
= NULL
;
749 tmp
.hash
= temp_slot_address_compute_hash (&tmp
);
750 t
= temp_slot_address_table
->find_with_hash (&tmp
, tmp
.hash
);
754 /* If we have a sum involving a register, see if it points to a temp
756 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
757 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
759 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
760 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
763 /* Last resort: Address is a virtual stack var address. */
765 if (strip_offset (x
, &offset
) == virtual_stack_vars_rtx
)
768 for (i
= max_slot_level (); i
>= 0; i
--)
769 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
770 if (known_in_range_p (offset
, p
->base_offset
, p
->full_size
))
777 /* Allocate a temporary stack slot and record it for possible later
780 MODE is the machine mode to be given to the returned rtx.
782 SIZE is the size in units of the space required. We do no rounding here
783 since assign_stack_local will do any required rounding.
785 TYPE is the type that will be used for the stack slot. */
788 assign_stack_temp_for_type (machine_mode mode
, poly_int64 size
, tree type
)
791 class temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
794 gcc_assert (known_size_p (size
));
796 align
= get_stack_local_alignment (type
, mode
);
798 /* Try to find an available, already-allocated temporary of the proper
799 mode which meets the size and alignment requirements. Choose the
800 smallest one with the closest alignment.
802 If assign_stack_temp is called outside of the tree->rtl expansion,
803 we cannot reuse the stack slots (that may still refer to
804 VIRTUAL_STACK_VARS_REGNUM). */
805 if (!virtuals_instantiated
)
807 for (p
= avail_temp_slots
; p
; p
= p
->next
)
809 if (p
->align
>= align
810 && known_ge (p
->size
, size
)
811 && GET_MODE (p
->slot
) == mode
812 && objects_must_conflict_p (p
->type
, type
)
814 || (known_eq (best_p
->size
, p
->size
)
815 ? best_p
->align
> p
->align
816 : known_ge (best_p
->size
, p
->size
))))
818 if (p
->align
== align
&& known_eq (p
->size
, size
))
821 cut_slot_from_list (selected
, &avail_temp_slots
);
830 /* Make our best, if any, the one to use. */
834 cut_slot_from_list (selected
, &avail_temp_slots
);
836 /* If there are enough aligned bytes left over, make them into a new
837 temp_slot so that the extra bytes don't get wasted. Do this only
838 for BLKmode slots, so that we can be sure of the alignment. */
839 if (GET_MODE (best_p
->slot
) == BLKmode
)
841 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
842 poly_int64 rounded_size
= aligned_upper_bound (size
, alignment
);
844 if (known_ge (best_p
->size
- rounded_size
, alignment
))
846 p
= ggc_alloc
<temp_slot
> ();
848 p
->size
= best_p
->size
- rounded_size
;
849 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
850 p
->full_size
= best_p
->full_size
- rounded_size
;
851 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
852 p
->align
= best_p
->align
;
853 p
->type
= best_p
->type
;
854 insert_slot_to_list (p
, &avail_temp_slots
);
856 vec_safe_push (stack_slot_list
, p
->slot
);
858 best_p
->size
= rounded_size
;
859 best_p
->full_size
= rounded_size
;
864 /* If we still didn't find one, make a new temporary. */
867 poly_int64 frame_offset_old
= frame_offset
;
869 p
= ggc_alloc
<temp_slot
> ();
871 /* We are passing an explicit alignment request to assign_stack_local.
872 One side effect of that is assign_stack_local will not round SIZE
873 to ensure the frame offset remains suitably aligned.
875 So for requests which depended on the rounding of SIZE, we go ahead
876 and round it now. We also make sure ALIGNMENT is at least
877 BIGGEST_ALIGNMENT. */
878 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
879 p
->slot
= assign_stack_local_1 (mode
,
881 ? aligned_upper_bound (size
,
889 /* The following slot size computation is necessary because we don't
890 know the actual size of the temporary slot until assign_stack_local
891 has performed all the frame alignment and size rounding for the
892 requested temporary. Note that extra space added for alignment
893 can be either above or below this stack slot depending on which
894 way the frame grows. We include the extra space if and only if it
895 is above this slot. */
896 if (FRAME_GROWS_DOWNWARD
)
897 p
->size
= frame_offset_old
- frame_offset
;
901 /* Now define the fields used by combine_temp_slots. */
902 if (FRAME_GROWS_DOWNWARD
)
904 p
->base_offset
= frame_offset
;
905 p
->full_size
= frame_offset_old
- frame_offset
;
909 p
->base_offset
= frame_offset_old
;
910 p
->full_size
= frame_offset
- frame_offset_old
;
919 p
->level
= temp_slot_level
;
920 n_temp_slots_in_use
++;
922 pp
= temp_slots_at_level (p
->level
);
923 insert_slot_to_list (p
, pp
);
924 insert_temp_slot_address (XEXP (p
->slot
, 0), p
);
926 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
927 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
928 vec_safe_push (stack_slot_list
, slot
);
930 /* If we know the alias set for the memory that will be used, use
931 it. If there's no TYPE, then we don't know anything about the
932 alias set for the memory. */
933 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
934 set_mem_align (slot
, align
);
936 /* If a type is specified, set the relevant flags. */
938 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
939 MEM_NOTRAP_P (slot
) = 1;
944 /* Allocate a temporary stack slot and record it for possible later
945 reuse. First two arguments are same as in preceding function. */
948 assign_stack_temp (machine_mode mode
, poly_int64 size
)
950 return assign_stack_temp_for_type (mode
, size
, NULL_TREE
);
953 /* Assign a temporary.
954 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
955 and so that should be used in error messages. In either case, we
956 allocate of the given type.
957 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
958 it is 0 if a register is OK.
959 DONT_PROMOTE is 1 if we should not promote values in register
963 assign_temp (tree type_or_decl
, int memory_required
,
964 int dont_promote ATTRIBUTE_UNUSED
)
972 if (DECL_P (type_or_decl
))
973 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
975 decl
= NULL
, type
= type_or_decl
;
977 mode
= TYPE_MODE (type
);
979 unsignedp
= TYPE_UNSIGNED (type
);
982 /* Allocating temporaries of TREE_ADDRESSABLE type must be done in the front
983 end. See also create_tmp_var for the gimplification-time check. */
984 gcc_assert (!TREE_ADDRESSABLE (type
) && COMPLETE_TYPE_P (type
));
986 if (mode
== BLKmode
|| memory_required
)
991 /* Unfortunately, we don't yet know how to allocate variable-sized
992 temporaries. However, sometimes we can find a fixed upper limit on
993 the size, so try that instead. */
994 if (!poly_int_tree_p (TYPE_SIZE_UNIT (type
), &size
))
995 size
= max_int_size_in_bytes (type
);
997 /* Zero sized arrays are a GNU C extension. Set size to 1 to avoid
998 problems with allocating the stack space. */
999 if (known_eq (size
, 0))
1002 /* The size of the temporary may be too large to fit into an integer. */
1003 /* ??? Not sure this should happen except for user silliness, so limit
1004 this to things that aren't compiler-generated temporaries. The
1005 rest of the time we'll die in assign_stack_temp_for_type. */
1007 && !known_size_p (size
)
1008 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
1010 error ("size of variable %q+D is too large", decl
);
1014 tmp
= assign_stack_temp_for_type (mode
, size
, type
);
1020 mode
= promote_mode (type
, mode
, &unsignedp
);
1023 return gen_reg_rtx (mode
);
1026 /* Combine temporary stack slots which are adjacent on the stack.
1028 This allows for better use of already allocated stack space. This is only
1029 done for BLKmode slots because we can be sure that we won't have alignment
1030 problems in this case. */
1033 combine_temp_slots (void)
1035 class temp_slot
*p
, *q
, *next
, *next_q
;
1038 /* We can't combine slots, because the information about which slot
1039 is in which alias set will be lost. */
1040 if (flag_strict_aliasing
)
1043 /* If there are a lot of temp slots, don't do anything unless
1044 high levels of optimization. */
1045 if (! flag_expensive_optimizations
)
1046 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
1047 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
1050 for (p
= avail_temp_slots
; p
; p
= next
)
1056 if (GET_MODE (p
->slot
) != BLKmode
)
1059 for (q
= p
->next
; q
; q
= next_q
)
1065 if (GET_MODE (q
->slot
) != BLKmode
)
1068 if (known_eq (p
->base_offset
+ p
->full_size
, q
->base_offset
))
1070 /* Q comes after P; combine Q into P. */
1072 p
->full_size
+= q
->full_size
;
1075 else if (known_eq (q
->base_offset
+ q
->full_size
, p
->base_offset
))
1077 /* P comes after Q; combine P into Q. */
1079 q
->full_size
+= p
->full_size
;
1084 cut_slot_from_list (q
, &avail_temp_slots
);
1087 /* Either delete P or advance past it. */
1089 cut_slot_from_list (p
, &avail_temp_slots
);
1093 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1094 slot that previously was known by OLD_RTX. */
1097 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
1101 if (rtx_equal_p (old_rtx
, new_rtx
))
1104 p
= find_temp_slot_from_address (old_rtx
);
1106 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1107 NEW_RTX is a register, see if one operand of the PLUS is a
1108 temporary location. If so, NEW_RTX points into it. Otherwise,
1109 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1110 in common between them. If so, try a recursive call on those
1114 if (GET_CODE (old_rtx
) != PLUS
)
1117 if (REG_P (new_rtx
))
1119 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
1120 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
1123 else if (GET_CODE (new_rtx
) != PLUS
)
1126 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
1127 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
1128 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
1129 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
1130 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
1131 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
1132 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
1133 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
1138 /* Otherwise add an alias for the temp's address. */
1139 insert_temp_slot_address (new_rtx
, p
);
1142 /* If X could be a reference to a temporary slot, mark that slot as
1143 belonging to the to one level higher than the current level. If X
1144 matched one of our slots, just mark that one. Otherwise, we can't
1145 easily predict which it is, so upgrade all of them.
1147 This is called when an ({...}) construct occurs and a statement
1148 returns a value in memory. */
1151 preserve_temp_slots (rtx x
)
1153 class temp_slot
*p
= 0, *next
;
1158 /* If X is a register that is being used as a pointer, see if we have
1159 a temporary slot we know it points to. */
1160 if (REG_P (x
) && REG_POINTER (x
))
1161 p
= find_temp_slot_from_address (x
);
1163 /* If X is not in memory or is at a constant address, it cannot be in
1164 a temporary slot. */
1165 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1168 /* First see if we can find a match. */
1170 p
= find_temp_slot_from_address (XEXP (x
, 0));
1174 if (p
->level
== temp_slot_level
)
1175 move_slot_to_level (p
, temp_slot_level
- 1);
1179 /* Otherwise, preserve all non-kept slots at this level. */
1180 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1183 move_slot_to_level (p
, temp_slot_level
- 1);
1187 /* Free all temporaries used so far. This is normally called at the
1188 end of generating code for a statement. */
1191 free_temp_slots (void)
1193 class temp_slot
*p
, *next
;
1194 bool some_available
= false;
1196 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1199 make_slot_available (p
);
1200 some_available
= true;
1205 remove_unused_temp_slot_addresses ();
1206 combine_temp_slots ();
1210 /* Push deeper into the nesting level for stack temporaries. */
1213 push_temp_slots (void)
1218 /* Pop a temporary nesting level. All slots in use in the current level
1222 pop_temp_slots (void)
1228 /* Initialize temporary slots. */
1231 init_temp_slots (void)
1233 /* We have not allocated any temporaries yet. */
1234 avail_temp_slots
= 0;
1235 vec_alloc (used_temp_slots
, 0);
1236 temp_slot_level
= 0;
1237 n_temp_slots_in_use
= 0;
1239 /* Set up the table to map addresses to temp slots. */
1240 if (! temp_slot_address_table
)
1241 temp_slot_address_table
= hash_table
<temp_address_hasher
>::create_ggc (32);
1243 temp_slot_address_table
->empty ();
1246 /* Functions and data structures to keep track of the values hard regs
1247 had at the start of the function. */
1249 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1250 and has_hard_reg_initial_val.. */
1251 struct GTY(()) initial_value_pair
{
1255 /* ??? This could be a VEC but there is currently no way to define an
1256 opaque VEC type. This could be worked around by defining struct
1257 initial_value_pair in function.h. */
1258 struct GTY(()) initial_value_struct
{
1261 initial_value_pair
* GTY ((length ("%h.num_entries"))) entries
;
1264 /* If a pseudo represents an initial hard reg (or expression), return
1265 it, else return NULL_RTX. */
1268 get_hard_reg_initial_reg (rtx reg
)
1270 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1276 for (i
= 0; i
< ivs
->num_entries
; i
++)
1277 if (rtx_equal_p (ivs
->entries
[i
].pseudo
, reg
))
1278 return ivs
->entries
[i
].hard_reg
;
1283 /* Make sure that there's a pseudo register of mode MODE that stores the
1284 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1287 get_hard_reg_initial_val (machine_mode mode
, unsigned int regno
)
1289 struct initial_value_struct
*ivs
;
1292 rv
= has_hard_reg_initial_val (mode
, regno
);
1296 ivs
= crtl
->hard_reg_initial_vals
;
1299 ivs
= ggc_alloc
<initial_value_struct
> ();
1300 ivs
->num_entries
= 0;
1301 ivs
->max_entries
= 5;
1302 ivs
->entries
= ggc_vec_alloc
<initial_value_pair
> (5);
1303 crtl
->hard_reg_initial_vals
= ivs
;
1306 if (ivs
->num_entries
>= ivs
->max_entries
)
1308 ivs
->max_entries
+= 5;
1309 ivs
->entries
= GGC_RESIZEVEC (initial_value_pair
, ivs
->entries
,
1313 ivs
->entries
[ivs
->num_entries
].hard_reg
= gen_rtx_REG (mode
, regno
);
1314 ivs
->entries
[ivs
->num_entries
].pseudo
= gen_reg_rtx (mode
);
1316 return ivs
->entries
[ivs
->num_entries
++].pseudo
;
1319 /* See if get_hard_reg_initial_val has been used to create a pseudo
1320 for the initial value of hard register REGNO in mode MODE. Return
1321 the associated pseudo if so, otherwise return NULL. */
1324 has_hard_reg_initial_val (machine_mode mode
, unsigned int regno
)
1326 struct initial_value_struct
*ivs
;
1329 ivs
= crtl
->hard_reg_initial_vals
;
1331 for (i
= 0; i
< ivs
->num_entries
; i
++)
1332 if (GET_MODE (ivs
->entries
[i
].hard_reg
) == mode
1333 && REGNO (ivs
->entries
[i
].hard_reg
) == regno
)
1334 return ivs
->entries
[i
].pseudo
;
1340 emit_initial_value_sets (void)
1342 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1350 for (i
= 0; i
< ivs
->num_entries
; i
++)
1351 emit_move_insn (ivs
->entries
[i
].pseudo
, ivs
->entries
[i
].hard_reg
);
1355 emit_insn_at_entry (seq
);
1359 /* Return the hardreg-pseudoreg initial values pair entry I and
1360 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1362 initial_value_entry (int i
, rtx
*hreg
, rtx
*preg
)
1364 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1365 if (!ivs
|| i
>= ivs
->num_entries
)
1368 *hreg
= ivs
->entries
[i
].hard_reg
;
1369 *preg
= ivs
->entries
[i
].pseudo
;
1373 /* These routines are responsible for converting virtual register references
1374 to the actual hard register references once RTL generation is complete.
1376 The following four variables are used for communication between the
1377 routines. They contain the offsets of the virtual registers from their
1378 respective hard registers. */
1380 static poly_int64 in_arg_offset
;
1381 static poly_int64 var_offset
;
1382 static poly_int64 dynamic_offset
;
1383 static poly_int64 out_arg_offset
;
1384 static poly_int64 cfa_offset
;
1386 /* In most machines, the stack pointer register is equivalent to the bottom
1389 #ifndef STACK_POINTER_OFFSET
1390 #define STACK_POINTER_OFFSET 0
1393 #if defined (REG_PARM_STACK_SPACE) && !defined (INCOMING_REG_PARM_STACK_SPACE)
1394 #define INCOMING_REG_PARM_STACK_SPACE REG_PARM_STACK_SPACE
1397 /* If not defined, pick an appropriate default for the offset of dynamically
1398 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1399 INCOMING_REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1401 #ifndef STACK_DYNAMIC_OFFSET
1403 /* The bottom of the stack points to the actual arguments. If
1404 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1405 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1406 stack space for register parameters is not pushed by the caller, but
1407 rather part of the fixed stack areas and hence not included in
1408 `crtl->outgoing_args_size'. Nevertheless, we must allow
1409 for it when allocating stack dynamic objects. */
1411 #ifdef INCOMING_REG_PARM_STACK_SPACE
1412 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1413 ((ACCUMULATE_OUTGOING_ARGS \
1414 ? (crtl->outgoing_args_size \
1415 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1416 : INCOMING_REG_PARM_STACK_SPACE (FNDECL))) \
1417 : 0) + (STACK_POINTER_OFFSET))
1419 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1420 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : poly_int64 (0)) \
1421 + (STACK_POINTER_OFFSET))
1426 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1427 is a virtual register, return the equivalent hard register and set the
1428 offset indirectly through the pointer. Otherwise, return 0. */
1431 instantiate_new_reg (rtx x
, poly_int64_pod
*poffset
)
1436 if (x
== virtual_incoming_args_rtx
)
1438 if (stack_realign_drap
)
1440 /* Replace virtual_incoming_args_rtx with internal arg
1441 pointer if DRAP is used to realign stack. */
1442 new_rtx
= crtl
->args
.internal_arg_pointer
;
1446 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1448 else if (x
== virtual_stack_vars_rtx
)
1449 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1450 else if (x
== virtual_stack_dynamic_rtx
)
1451 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1452 else if (x
== virtual_outgoing_args_rtx
)
1453 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1454 else if (x
== virtual_cfa_rtx
)
1456 #ifdef FRAME_POINTER_CFA_OFFSET
1457 new_rtx
= frame_pointer_rtx
;
1459 new_rtx
= arg_pointer_rtx
;
1461 offset
= cfa_offset
;
1463 else if (x
== virtual_preferred_stack_boundary_rtx
)
1465 new_rtx
= GEN_INT (crtl
->preferred_stack_boundary
/ BITS_PER_UNIT
);
1475 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1476 registers present inside of *LOC. The expression is simplified,
1477 as much as possible, but is not to be considered "valid" in any sense
1478 implied by the target. Return true if any change is made. */
1481 instantiate_virtual_regs_in_rtx (rtx
*loc
)
1485 bool changed
= false;
1486 subrtx_ptr_iterator::array_type array
;
1487 FOR_EACH_SUBRTX_PTR (iter
, array
, loc
, NONCONST
)
1494 switch (GET_CODE (x
))
1497 new_rtx
= instantiate_new_reg (x
, &offset
);
1500 *loc
= plus_constant (GET_MODE (x
), new_rtx
, offset
);
1503 iter
.skip_subrtxes ();
1507 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1510 XEXP (x
, 0) = new_rtx
;
1511 *loc
= plus_constant (GET_MODE (x
), x
, offset
, true);
1513 iter
.skip_subrtxes ();
1517 /* FIXME -- from old code */
1518 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1519 we can commute the PLUS and SUBREG because pointers into the
1520 frame are well-behaved. */
1531 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1532 matches the predicate for insn CODE operand OPERAND. */
1535 safe_insn_predicate (int code
, int operand
, rtx x
)
1537 return code
< 0 || insn_operand_matches ((enum insn_code
) code
, operand
, x
);
1540 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1541 registers present inside of insn. The result will be a valid insn. */
1544 instantiate_virtual_regs_in_insn (rtx_insn
*insn
)
1548 bool any_change
= false;
1549 rtx set
, new_rtx
, x
;
1552 /* There are some special cases to be handled first. */
1553 set
= single_set (insn
);
1556 /* We're allowed to assign to a virtual register. This is interpreted
1557 to mean that the underlying register gets assigned the inverse
1558 transformation. This is used, for example, in the handling of
1560 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1565 instantiate_virtual_regs_in_rtx (&SET_SRC (set
));
1566 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1567 gen_int_mode (-offset
, GET_MODE (new_rtx
)));
1568 x
= force_operand (x
, new_rtx
);
1570 emit_move_insn (new_rtx
, x
);
1575 emit_insn_before (seq
, insn
);
1580 /* Handle a straight copy from a virtual register by generating a
1581 new add insn. The difference between this and falling through
1582 to the generic case is avoiding a new pseudo and eliminating a
1583 move insn in the initial rtl stream. */
1584 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1586 && maybe_ne (offset
, 0)
1587 && REG_P (SET_DEST (set
))
1588 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1592 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
, new_rtx
,
1593 gen_int_mode (offset
,
1594 GET_MODE (SET_DEST (set
))),
1595 SET_DEST (set
), 1, OPTAB_LIB_WIDEN
);
1596 if (x
!= SET_DEST (set
))
1597 emit_move_insn (SET_DEST (set
), x
);
1602 emit_insn_before (seq
, insn
);
1607 extract_insn (insn
);
1608 insn_code
= INSN_CODE (insn
);
1610 /* Handle a plus involving a virtual register by determining if the
1611 operands remain valid if they're modified in place. */
1613 if (GET_CODE (SET_SRC (set
)) == PLUS
1614 && recog_data
.n_operands
>= 3
1615 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1616 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1617 && poly_int_rtx_p (recog_data
.operand
[2], &delta
)
1618 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1622 /* If the sum is zero, then replace with a plain move. */
1623 if (known_eq (offset
, 0)
1624 && REG_P (SET_DEST (set
))
1625 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1628 emit_move_insn (SET_DEST (set
), new_rtx
);
1632 emit_insn_before (seq
, insn
);
1637 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1639 /* Using validate_change and apply_change_group here leaves
1640 recog_data in an invalid state. Since we know exactly what
1641 we want to check, do those two by hand. */
1642 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1643 && safe_insn_predicate (insn_code
, 2, x
))
1645 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1646 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1649 /* Fall through into the regular operand fixup loop in
1650 order to take care of operands other than 1 and 2. */
1656 extract_insn (insn
);
1657 insn_code
= INSN_CODE (insn
);
1660 /* In the general case, we expect virtual registers to appear only in
1661 operands, and then only as either bare registers or inside memories. */
1662 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1664 x
= recog_data
.operand
[i
];
1665 switch (GET_CODE (x
))
1669 rtx addr
= XEXP (x
, 0);
1671 if (!instantiate_virtual_regs_in_rtx (&addr
))
1675 x
= replace_equiv_address (x
, addr
, true);
1676 /* It may happen that the address with the virtual reg
1677 was valid (e.g. based on the virtual stack reg, which might
1678 be acceptable to the predicates with all offsets), whereas
1679 the address now isn't anymore, for instance when the address
1680 is still offsetted, but the base reg isn't virtual-stack-reg
1681 anymore. Below we would do a force_reg on the whole operand,
1682 but this insn might actually only accept memory. Hence,
1683 before doing that last resort, try to reload the address into
1684 a register, so this operand stays a MEM. */
1685 if (!safe_insn_predicate (insn_code
, i
, x
))
1687 addr
= force_reg (GET_MODE (addr
), addr
);
1688 x
= replace_equiv_address (x
, addr
, true);
1693 emit_insn_before (seq
, insn
);
1698 new_rtx
= instantiate_new_reg (x
, &offset
);
1699 if (new_rtx
== NULL
)
1701 if (known_eq (offset
, 0))
1707 /* Careful, special mode predicates may have stuff in
1708 insn_data[insn_code].operand[i].mode that isn't useful
1709 to us for computing a new value. */
1710 /* ??? Recognize address_operand and/or "p" constraints
1711 to see if (plus new offset) is a valid before we put
1712 this through expand_simple_binop. */
1713 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1714 gen_int_mode (offset
, GET_MODE (x
)),
1715 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1718 emit_insn_before (seq
, insn
);
1723 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1724 if (new_rtx
== NULL
)
1726 if (maybe_ne (offset
, 0))
1729 new_rtx
= expand_simple_binop
1730 (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1731 gen_int_mode (offset
, GET_MODE (new_rtx
)),
1732 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1735 emit_insn_before (seq
, insn
);
1737 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1738 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1746 /* At this point, X contains the new value for the operand.
1747 Validate the new value vs the insn predicate. Note that
1748 asm insns will have insn_code -1 here. */
1749 if (!safe_insn_predicate (insn_code
, i
, x
))
1754 gcc_assert (REGNO (x
) <= LAST_VIRTUAL_REGISTER
);
1755 x
= copy_to_reg (x
);
1758 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1762 emit_insn_before (seq
, insn
);
1765 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1771 /* Propagate operand changes into the duplicates. */
1772 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1773 *recog_data
.dup_loc
[i
]
1774 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1776 /* Force re-recognition of the instruction for validation. */
1777 INSN_CODE (insn
) = -1;
1780 if (asm_noperands (PATTERN (insn
)) >= 0)
1782 if (!check_asm_operands (PATTERN (insn
)))
1784 error_for_asm (insn
, "impossible constraint in %<asm%>");
1785 /* For asm goto, instead of fixing up all the edges
1786 just clear the template and clear input operands
1787 (asm goto doesn't have any output operands). */
1790 rtx asm_op
= extract_asm_operands (PATTERN (insn
));
1791 ASM_OPERANDS_TEMPLATE (asm_op
) = ggc_strdup ("");
1792 ASM_OPERANDS_INPUT_VEC (asm_op
) = rtvec_alloc (0);
1793 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op
) = rtvec_alloc (0);
1801 if (recog_memoized (insn
) < 0)
1802 fatal_insn_not_found (insn
);
1806 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1807 do any instantiation required. */
1810 instantiate_decl_rtl (rtx x
)
1817 /* If this is a CONCAT, recurse for the pieces. */
1818 if (GET_CODE (x
) == CONCAT
)
1820 instantiate_decl_rtl (XEXP (x
, 0));
1821 instantiate_decl_rtl (XEXP (x
, 1));
1825 /* If this is not a MEM, no need to do anything. Similarly if the
1826 address is a constant or a register that is not a virtual register. */
1831 if (CONSTANT_P (addr
)
1833 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1834 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1837 instantiate_virtual_regs_in_rtx (&XEXP (x
, 0));
1840 /* Helper for instantiate_decls called via walk_tree: Process all decls
1841 in the given DECL_VALUE_EXPR. */
1844 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1852 if (DECL_RTL_SET_P (t
))
1853 instantiate_decl_rtl (DECL_RTL (t
));
1854 if (TREE_CODE (t
) == PARM_DECL
&& DECL_NAMELESS (t
)
1855 && DECL_INCOMING_RTL (t
))
1856 instantiate_decl_rtl (DECL_INCOMING_RTL (t
));
1857 if ((VAR_P (t
) || TREE_CODE (t
) == RESULT_DECL
)
1858 && DECL_HAS_VALUE_EXPR_P (t
))
1860 tree v
= DECL_VALUE_EXPR (t
);
1861 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1868 /* Subroutine of instantiate_decls: Process all decls in the given
1869 BLOCK node and all its subblocks. */
1872 instantiate_decls_1 (tree let
)
1876 for (t
= BLOCK_VARS (let
); t
; t
= DECL_CHAIN (t
))
1878 if (DECL_RTL_SET_P (t
))
1879 instantiate_decl_rtl (DECL_RTL (t
));
1880 if (VAR_P (t
) && DECL_HAS_VALUE_EXPR_P (t
))
1882 tree v
= DECL_VALUE_EXPR (t
);
1883 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1887 /* Process all subblocks. */
1888 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1889 instantiate_decls_1 (t
);
1892 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1893 all virtual registers in their DECL_RTL's. */
1896 instantiate_decls (tree fndecl
)
1901 /* Process all parameters of the function. */
1902 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= DECL_CHAIN (decl
))
1904 instantiate_decl_rtl (DECL_RTL (decl
));
1905 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1906 if (DECL_HAS_VALUE_EXPR_P (decl
))
1908 tree v
= DECL_VALUE_EXPR (decl
);
1909 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1913 if ((decl
= DECL_RESULT (fndecl
))
1914 && TREE_CODE (decl
) == RESULT_DECL
)
1916 if (DECL_RTL_SET_P (decl
))
1917 instantiate_decl_rtl (DECL_RTL (decl
));
1918 if (DECL_HAS_VALUE_EXPR_P (decl
))
1920 tree v
= DECL_VALUE_EXPR (decl
);
1921 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1925 /* Process the saved static chain if it exists. */
1926 decl
= DECL_STRUCT_FUNCTION (fndecl
)->static_chain_decl
;
1927 if (decl
&& DECL_HAS_VALUE_EXPR_P (decl
))
1928 instantiate_decl_rtl (DECL_RTL (DECL_VALUE_EXPR (decl
)));
1930 /* Now process all variables defined in the function or its subblocks. */
1931 if (DECL_INITIAL (fndecl
))
1932 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1934 FOR_EACH_LOCAL_DECL (cfun
, ix
, decl
)
1935 if (DECL_RTL_SET_P (decl
))
1936 instantiate_decl_rtl (DECL_RTL (decl
));
1937 vec_free (cfun
->local_decls
);
1940 /* Pass through the INSNS of function FNDECL and convert virtual register
1941 references to hard register references. */
1944 instantiate_virtual_regs (void)
1948 /* Compute the offsets to use for this function. */
1949 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1950 var_offset
= targetm
.starting_frame_offset ();
1951 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1952 out_arg_offset
= STACK_POINTER_OFFSET
;
1953 #ifdef FRAME_POINTER_CFA_OFFSET
1954 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1956 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1959 /* Initialize recognition, indicating that volatile is OK. */
1962 /* Scan through all the insns, instantiating every virtual register still
1964 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1967 /* These patterns in the instruction stream can never be recognized.
1968 Fortunately, they shouldn't contain virtual registers either. */
1969 if (GET_CODE (PATTERN (insn
)) == USE
1970 || GET_CODE (PATTERN (insn
)) == CLOBBER
1971 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
1972 || DEBUG_MARKER_INSN_P (insn
))
1974 else if (DEBUG_BIND_INSN_P (insn
))
1975 instantiate_virtual_regs_in_rtx (INSN_VAR_LOCATION_PTR (insn
));
1977 instantiate_virtual_regs_in_insn (insn
);
1979 if (insn
->deleted ())
1982 instantiate_virtual_regs_in_rtx (®_NOTES (insn
));
1984 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1986 instantiate_virtual_regs_in_rtx (&CALL_INSN_FUNCTION_USAGE (insn
));
1989 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1990 instantiate_decls (current_function_decl
);
1992 targetm
.instantiate_decls ();
1994 /* Indicate that, from now on, assign_stack_local should use
1995 frame_pointer_rtx. */
1996 virtuals_instantiated
= 1;
2003 const pass_data pass_data_instantiate_virtual_regs
=
2005 RTL_PASS
, /* type */
2007 OPTGROUP_NONE
, /* optinfo_flags */
2008 TV_NONE
, /* tv_id */
2009 0, /* properties_required */
2010 0, /* properties_provided */
2011 0, /* properties_destroyed */
2012 0, /* todo_flags_start */
2013 0, /* todo_flags_finish */
2016 class pass_instantiate_virtual_regs
: public rtl_opt_pass
2019 pass_instantiate_virtual_regs (gcc::context
*ctxt
)
2020 : rtl_opt_pass (pass_data_instantiate_virtual_regs
, ctxt
)
2023 /* opt_pass methods: */
2024 virtual unsigned int execute (function
*)
2026 return instantiate_virtual_regs ();
2029 }; // class pass_instantiate_virtual_regs
2034 make_pass_instantiate_virtual_regs (gcc::context
*ctxt
)
2036 return new pass_instantiate_virtual_regs (ctxt
);
2040 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
2041 This means a type for which function calls must pass an address to the
2042 function or get an address back from the function.
2043 EXP may be a type node or an expression (whose type is tested). */
2046 aggregate_value_p (const_tree exp
, const_tree fntype
)
2048 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
2049 int i
, regno
, nregs
;
2053 switch (TREE_CODE (fntype
))
2057 tree fndecl
= get_callee_fndecl (fntype
);
2059 fntype
= TREE_TYPE (fndecl
);
2060 else if (CALL_EXPR_FN (fntype
))
2061 fntype
= TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype
)));
2063 /* For internal functions, assume nothing needs to be
2064 returned in memory. */
2069 fntype
= TREE_TYPE (fntype
);
2074 case IDENTIFIER_NODE
:
2078 /* We don't expect other tree types here. */
2082 if (VOID_TYPE_P (type
))
2085 /* If a record should be passed the same as its first (and only) member
2086 don't pass it as an aggregate. */
2087 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2088 return aggregate_value_p (first_field (type
), fntype
);
2090 /* If the front end has decided that this needs to be passed by
2091 reference, do so. */
2092 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
2093 && DECL_BY_REFERENCE (exp
))
2096 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2097 if (fntype
&& TREE_ADDRESSABLE (fntype
))
2100 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2101 and thus can't be returned in registers. */
2102 if (TREE_ADDRESSABLE (type
))
2105 if (TYPE_EMPTY_P (type
))
2108 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
2111 if (targetm
.calls
.return_in_memory (type
, fntype
))
2114 /* Make sure we have suitable call-clobbered regs to return
2115 the value in; if not, we must return it in memory. */
2116 reg
= hard_function_value (type
, 0, fntype
, 0);
2118 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2123 /* Use the default ABI if the type of the function isn't known.
2124 The scheme for handling interoperability between different ABIs
2125 requires us to be able to tell when we're calling a function with
2126 a nondefault ABI. */
2127 const predefined_function_abi
&abi
= (fntype
2128 ? fntype_abi (fntype
)
2129 : default_function_abi
);
2130 regno
= REGNO (reg
);
2131 nregs
= hard_regno_nregs (regno
, TYPE_MODE (type
));
2132 for (i
= 0; i
< nregs
; i
++)
2133 if (!fixed_regs
[regno
+ i
] && !abi
.clobbers_full_reg_p (regno
+ i
))
2139 /* Return true if we should assign DECL a pseudo register; false if it
2140 should live on the local stack. */
2143 use_register_for_decl (const_tree decl
)
2145 if (TREE_CODE (decl
) == SSA_NAME
)
2147 /* We often try to use the SSA_NAME, instead of its underlying
2148 decl, to get type information and guide decisions, to avoid
2149 differences of behavior between anonymous and named
2150 variables, but in this one case we have to go for the actual
2151 variable if there is one. The main reason is that, at least
2152 at -O0, we want to place user variables on the stack, but we
2153 don't mind using pseudos for anonymous or ignored temps.
2154 Should we take the SSA_NAME, we'd conclude all SSA_NAMEs
2155 should go in pseudos, whereas their corresponding variables
2156 might have to go on the stack. So, disregarding the decl
2157 here would negatively impact debug info at -O0, enable
2158 coalescing between SSA_NAMEs that ought to get different
2159 stack/pseudo assignments, and get the incoming argument
2160 processing thoroughly confused by PARM_DECLs expected to live
2161 in stack slots but assigned to pseudos. */
2162 if (!SSA_NAME_VAR (decl
))
2163 return TYPE_MODE (TREE_TYPE (decl
)) != BLKmode
2164 && !(flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)));
2166 decl
= SSA_NAME_VAR (decl
);
2169 /* Honor volatile. */
2170 if (TREE_SIDE_EFFECTS (decl
))
2173 /* Honor addressability. */
2174 if (TREE_ADDRESSABLE (decl
))
2177 /* RESULT_DECLs are a bit special in that they're assigned without
2178 regard to use_register_for_decl, but we generally only store in
2179 them. If we coalesce their SSA NAMEs, we'd better return a
2180 result that matches the assignment in expand_function_start. */
2181 if (TREE_CODE (decl
) == RESULT_DECL
)
2183 /* If it's not an aggregate, we're going to use a REG or a
2184 PARALLEL containing a REG. */
2185 if (!aggregate_value_p (decl
, current_function_decl
))
2188 /* If expand_function_start determines the return value, we'll
2189 use MEM if it's not by reference. */
2190 if (cfun
->returns_pcc_struct
2191 || (targetm
.calls
.struct_value_rtx
2192 (TREE_TYPE (current_function_decl
), 1)))
2193 return DECL_BY_REFERENCE (decl
);
2195 /* Otherwise, we're taking an extra all.function_result_decl
2196 argument. It's set up in assign_parms_augmented_arg_list,
2197 under the (negated) conditions above, and then it's used to
2198 set up the RESULT_DECL rtl in assign_params, after looping
2199 over all parameters. Now, if the RESULT_DECL is not by
2200 reference, we'll use a MEM either way. */
2201 if (!DECL_BY_REFERENCE (decl
))
2204 /* Otherwise, if RESULT_DECL is DECL_BY_REFERENCE, it will take
2205 the function_result_decl's assignment. Since it's a pointer,
2206 we can short-circuit a number of the tests below, and we must
2207 duplicat e them because we don't have the
2208 function_result_decl to test. */
2209 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2211 /* We don't set DECL_IGNORED_P for the function_result_decl. */
2214 /* We don't set DECL_REGISTER for the function_result_decl. */
2218 /* Only register-like things go in registers. */
2219 if (DECL_MODE (decl
) == BLKmode
)
2222 /* If -ffloat-store specified, don't put explicit float variables
2224 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2225 propagates values across these stores, and it probably shouldn't. */
2226 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
2229 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2232 /* If we're not interested in tracking debugging information for
2233 this decl, then we can certainly put it in a register. */
2234 if (DECL_IGNORED_P (decl
))
2240 /* Thunks force a tail call even at -O0 so we need to avoid creating a
2241 dangling reference in case the parameter is passed by reference. */
2242 if (TREE_CODE (decl
) == PARM_DECL
&& cfun
->tail_call_marked
)
2245 if (!DECL_REGISTER (decl
))
2248 /* When not optimizing, disregard register keyword for types that
2249 could have methods, otherwise the methods won't be callable from
2251 if (RECORD_OR_UNION_TYPE_P (TREE_TYPE (decl
)))
2257 /* Structures to communicate between the subroutines of assign_parms.
2258 The first holds data persistent across all parameters, the second
2259 is cleared out for each parameter. */
2261 struct assign_parm_data_all
2263 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2264 should become a job of the target or otherwise encapsulated. */
2265 CUMULATIVE_ARGS args_so_far_v
;
2266 cumulative_args_t args_so_far
;
2267 struct args_size stack_args_size
;
2268 tree function_result_decl
;
2270 rtx_insn
*first_conversion_insn
;
2271 rtx_insn
*last_conversion_insn
;
2272 HOST_WIDE_INT pretend_args_size
;
2273 HOST_WIDE_INT extra_pretend_bytes
;
2274 int reg_parm_stack_space
;
2277 struct assign_parm_data_one
2280 function_arg_info arg
;
2283 machine_mode nominal_mode
;
2284 machine_mode passed_mode
;
2285 struct locate_and_pad_arg_data locate
;
2289 /* A subroutine of assign_parms. Initialize ALL. */
2292 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2294 tree fntype ATTRIBUTE_UNUSED
;
2296 memset (all
, 0, sizeof (*all
));
2298 fntype
= TREE_TYPE (current_function_decl
);
2300 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2301 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
);
2303 INIT_CUMULATIVE_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
,
2304 current_function_decl
, -1);
2306 all
->args_so_far
= pack_cumulative_args (&all
->args_so_far_v
);
2308 #ifdef INCOMING_REG_PARM_STACK_SPACE
2309 all
->reg_parm_stack_space
2310 = INCOMING_REG_PARM_STACK_SPACE (current_function_decl
);
2314 /* If ARGS contains entries with complex types, split the entry into two
2315 entries of the component type. Return a new list of substitutions are
2316 needed, else the old list. */
2319 split_complex_args (vec
<tree
> *args
)
2324 FOR_EACH_VEC_ELT (*args
, i
, p
)
2326 tree type
= TREE_TYPE (p
);
2327 if (TREE_CODE (type
) == COMPLEX_TYPE
2328 && targetm
.calls
.split_complex_arg (type
))
2331 tree subtype
= TREE_TYPE (type
);
2332 bool addressable
= TREE_ADDRESSABLE (p
);
2334 /* Rewrite the PARM_DECL's type with its component. */
2336 TREE_TYPE (p
) = subtype
;
2337 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2338 SET_DECL_MODE (p
, VOIDmode
);
2339 DECL_SIZE (p
) = NULL
;
2340 DECL_SIZE_UNIT (p
) = NULL
;
2341 /* If this arg must go in memory, put it in a pseudo here.
2342 We can't allow it to go in memory as per normal parms,
2343 because the usual place might not have the imag part
2344 adjacent to the real part. */
2345 DECL_ARTIFICIAL (p
) = addressable
;
2346 DECL_IGNORED_P (p
) = addressable
;
2347 TREE_ADDRESSABLE (p
) = 0;
2351 /* Build a second synthetic decl. */
2352 decl
= build_decl (EXPR_LOCATION (p
),
2353 PARM_DECL
, NULL_TREE
, subtype
);
2354 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2355 DECL_ARTIFICIAL (decl
) = addressable
;
2356 DECL_IGNORED_P (decl
) = addressable
;
2357 layout_decl (decl
, 0);
2358 args
->safe_insert (++i
, decl
);
2363 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2364 the hidden struct return argument, and (abi willing) complex args.
2365 Return the new parameter list. */
2368 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2370 tree fndecl
= current_function_decl
;
2371 tree fntype
= TREE_TYPE (fndecl
);
2372 vec
<tree
> fnargs
= vNULL
;
2375 for (arg
= DECL_ARGUMENTS (fndecl
); arg
; arg
= DECL_CHAIN (arg
))
2376 fnargs
.safe_push (arg
);
2378 all
->orig_fnargs
= DECL_ARGUMENTS (fndecl
);
2380 /* If struct value address is treated as the first argument, make it so. */
2381 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2382 && ! cfun
->returns_pcc_struct
2383 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2385 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2388 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2389 PARM_DECL
, get_identifier (".result_ptr"), type
);
2390 DECL_ARG_TYPE (decl
) = type
;
2391 DECL_ARTIFICIAL (decl
) = 1;
2392 DECL_NAMELESS (decl
) = 1;
2393 TREE_CONSTANT (decl
) = 1;
2394 /* We don't set DECL_IGNORED_P or DECL_REGISTER here. If this
2395 changes, the end of the RESULT_DECL handling block in
2396 use_register_for_decl must be adjusted to match. */
2398 DECL_CHAIN (decl
) = all
->orig_fnargs
;
2399 all
->orig_fnargs
= decl
;
2400 fnargs
.safe_insert (0, decl
);
2402 all
->function_result_decl
= decl
;
2405 /* If the target wants to split complex arguments into scalars, do so. */
2406 if (targetm
.calls
.split_complex_arg
)
2407 split_complex_args (&fnargs
);
2412 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2413 data for the parameter. Incorporate ABI specifics such as pass-by-
2414 reference and type promotion. */
2417 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2418 struct assign_parm_data_one
*data
)
2422 #ifndef BROKEN_VALUE_INITIALIZATION
2423 *data
= assign_parm_data_one ();
2425 /* Old versions of GCC used to miscompile the above by only initializing
2426 the members with explicit constructors and copying garbage
2427 to the other members. */
2428 assign_parm_data_one zero_data
= {};
2432 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2434 data
->arg
.named
= 1; /* No variadic parms. */
2435 else if (DECL_CHAIN (parm
))
2436 data
->arg
.named
= 1; /* Not the last non-variadic parm. */
2437 else if (targetm
.calls
.strict_argument_naming (all
->args_so_far
))
2438 data
->arg
.named
= 1; /* Only variadic ones are unnamed. */
2440 data
->arg
.named
= 0; /* Treat as variadic. */
2442 data
->nominal_type
= TREE_TYPE (parm
);
2443 data
->arg
.type
= DECL_ARG_TYPE (parm
);
2445 /* Look out for errors propagating this far. Also, if the parameter's
2446 type is void then its value doesn't matter. */
2447 if (TREE_TYPE (parm
) == error_mark_node
2448 /* This can happen after weird syntax errors
2449 or if an enum type is defined among the parms. */
2450 || TREE_CODE (parm
) != PARM_DECL
2451 || data
->arg
.type
== NULL
2452 || VOID_TYPE_P (data
->nominal_type
))
2454 data
->nominal_type
= data
->arg
.type
= void_type_node
;
2455 data
->nominal_mode
= data
->passed_mode
= data
->arg
.mode
= VOIDmode
;
2459 /* Find mode of arg as it is passed, and mode of arg as it should be
2460 during execution of this function. */
2461 data
->passed_mode
= data
->arg
.mode
= TYPE_MODE (data
->arg
.type
);
2462 data
->nominal_mode
= TYPE_MODE (data
->nominal_type
);
2464 /* If the parm is to be passed as a transparent union or record, use the
2465 type of the first field for the tests below. We have already verified
2466 that the modes are the same. */
2467 if (RECORD_OR_UNION_TYPE_P (data
->arg
.type
)
2468 && TYPE_TRANSPARENT_AGGR (data
->arg
.type
))
2469 data
->arg
.type
= TREE_TYPE (first_field (data
->arg
.type
));
2471 /* See if this arg was passed by invisible reference. */
2472 if (apply_pass_by_reference_rules (&all
->args_so_far_v
, data
->arg
))
2474 data
->nominal_type
= data
->arg
.type
;
2475 data
->passed_mode
= data
->nominal_mode
= data
->arg
.mode
;
2478 /* Find mode as it is passed by the ABI. */
2479 unsignedp
= TYPE_UNSIGNED (data
->arg
.type
);
2481 = promote_function_mode (data
->arg
.type
, data
->arg
.mode
, &unsignedp
,
2482 TREE_TYPE (current_function_decl
), 0);
2485 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2488 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2489 struct assign_parm_data_one
*data
, bool no_rtl
)
2491 int varargs_pretend_bytes
= 0;
2493 function_arg_info last_named_arg
= data
->arg
;
2494 last_named_arg
.named
= true;
2495 targetm
.calls
.setup_incoming_varargs (all
->args_so_far
, last_named_arg
,
2496 &varargs_pretend_bytes
, no_rtl
);
2498 /* If the back-end has requested extra stack space, record how much is
2499 needed. Do not change pretend_args_size otherwise since it may be
2500 nonzero from an earlier partial argument. */
2501 if (varargs_pretend_bytes
> 0)
2502 all
->pretend_args_size
= varargs_pretend_bytes
;
2505 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2506 the incoming location of the current parameter. */
2509 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2510 struct assign_parm_data_one
*data
)
2512 HOST_WIDE_INT pretend_bytes
= 0;
2516 if (data
->arg
.mode
== VOIDmode
)
2518 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2522 targetm
.calls
.warn_parameter_passing_abi (all
->args_so_far
,
2525 entry_parm
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2527 if (entry_parm
== 0)
2528 data
->arg
.mode
= data
->passed_mode
;
2530 /* Determine parm's home in the stack, in case it arrives in the stack
2531 or we should pretend it did. Compute the stack position and rtx where
2532 the argument arrives and its size.
2534 There is one complexity here: If this was a parameter that would
2535 have been passed in registers, but wasn't only because it is
2536 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2537 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2538 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2539 as it was the previous time. */
2540 in_regs
= (entry_parm
!= 0);
2541 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2544 if (!in_regs
&& !data
->arg
.named
)
2546 if (targetm
.calls
.pretend_outgoing_varargs_named (all
->args_so_far
))
2549 function_arg_info named_arg
= data
->arg
;
2550 named_arg
.named
= true;
2551 tem
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2553 in_regs
= tem
!= NULL
;
2557 /* If this parameter was passed both in registers and in the stack, use
2558 the copy on the stack. */
2559 if (targetm
.calls
.must_pass_in_stack (data
->arg
))
2566 partial
= targetm
.calls
.arg_partial_bytes (all
->args_so_far
, data
->arg
);
2567 data
->partial
= partial
;
2569 /* The caller might already have allocated stack space for the
2570 register parameters. */
2571 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2573 /* Part of this argument is passed in registers and part
2574 is passed on the stack. Ask the prologue code to extend
2575 the stack part so that we can recreate the full value.
2577 PRETEND_BYTES is the size of the registers we need to store.
2578 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2579 stack space that the prologue should allocate.
2581 Internally, gcc assumes that the argument pointer is aligned
2582 to STACK_BOUNDARY bits. This is used both for alignment
2583 optimizations (see init_emit) and to locate arguments that are
2584 aligned to more than PARM_BOUNDARY bits. We must preserve this
2585 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2586 a stack boundary. */
2588 /* We assume at most one partial arg, and it must be the first
2589 argument on the stack. */
2590 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2592 pretend_bytes
= partial
;
2593 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2595 /* We want to align relative to the actual stack pointer, so
2596 don't include this in the stack size until later. */
2597 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2601 locate_and_pad_parm (data
->arg
.mode
, data
->arg
.type
, in_regs
,
2602 all
->reg_parm_stack_space
,
2603 entry_parm
? data
->partial
: 0, current_function_decl
,
2604 &all
->stack_args_size
, &data
->locate
);
2606 /* Update parm_stack_boundary if this parameter is passed in the
2608 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2609 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2611 /* Adjust offsets to include the pretend args. */
2612 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2613 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2614 data
->locate
.offset
.constant
+= pretend_bytes
;
2616 data
->entry_parm
= entry_parm
;
2619 /* A subroutine of assign_parms. If there is actually space on the stack
2620 for this parm, count it in stack_args_size and return true. */
2623 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2624 struct assign_parm_data_one
*data
)
2626 /* Trivially true if we've no incoming register. */
2627 if (data
->entry_parm
== NULL
)
2629 /* Also true if we're partially in registers and partially not,
2630 since we've arranged to drop the entire argument on the stack. */
2631 else if (data
->partial
!= 0)
2633 /* Also true if the target says that it's passed in both registers
2634 and on the stack. */
2635 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2636 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2638 /* Also true if the target says that there's stack allocated for
2639 all register parameters. */
2640 else if (all
->reg_parm_stack_space
> 0)
2642 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2646 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2647 if (data
->locate
.size
.var
)
2648 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2653 /* A subroutine of assign_parms. Given that this parameter is allocated
2654 stack space by the ABI, find it. */
2657 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2659 rtx offset_rtx
, stack_parm
;
2660 unsigned int align
, boundary
;
2662 /* If we're passing this arg using a reg, make its stack home the
2663 aligned stack slot. */
2664 if (data
->entry_parm
)
2665 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2667 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2669 stack_parm
= crtl
->args
.internal_arg_pointer
;
2670 if (offset_rtx
!= const0_rtx
)
2671 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2672 stack_parm
= gen_rtx_MEM (data
->arg
.mode
, stack_parm
);
2674 if (!data
->arg
.pass_by_reference
)
2676 set_mem_attributes (stack_parm
, parm
, 1);
2677 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2678 while promoted mode's size is needed. */
2679 if (data
->arg
.mode
!= BLKmode
2680 && data
->arg
.mode
!= DECL_MODE (parm
))
2682 set_mem_size (stack_parm
, GET_MODE_SIZE (data
->arg
.mode
));
2683 if (MEM_EXPR (stack_parm
) && MEM_OFFSET_KNOWN_P (stack_parm
))
2685 poly_int64 offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2687 if (maybe_ne (offset
, 0))
2688 set_mem_offset (stack_parm
, MEM_OFFSET (stack_parm
) - offset
);
2693 boundary
= data
->locate
.boundary
;
2694 align
= BITS_PER_UNIT
;
2696 /* If we're padding upward, we know that the alignment of the slot
2697 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2698 intentionally forcing upward padding. Otherwise we have to come
2699 up with a guess at the alignment based on OFFSET_RTX. */
2701 if (data
->locate
.where_pad
== PAD_NONE
|| data
->entry_parm
)
2703 else if (data
->locate
.where_pad
== PAD_UPWARD
)
2706 /* If the argument offset is actually more aligned than the nominal
2707 stack slot boundary, take advantage of that excess alignment.
2708 Don't make any assumptions if STACK_POINTER_OFFSET is in use. */
2709 if (poly_int_rtx_p (offset_rtx
, &offset
)
2710 && known_eq (STACK_POINTER_OFFSET
, 0))
2712 unsigned int offset_align
= known_alignment (offset
) * BITS_PER_UNIT
;
2713 if (offset_align
== 0 || offset_align
> STACK_BOUNDARY
)
2714 offset_align
= STACK_BOUNDARY
;
2715 align
= MAX (align
, offset_align
);
2718 else if (poly_int_rtx_p (offset_rtx
, &offset
))
2720 align
= least_bit_hwi (boundary
);
2721 unsigned int offset_align
= known_alignment (offset
) * BITS_PER_UNIT
;
2722 if (offset_align
!= 0)
2723 align
= MIN (align
, offset_align
);
2725 set_mem_align (stack_parm
, align
);
2727 if (data
->entry_parm
)
2728 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2730 data
->stack_parm
= stack_parm
;
2733 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2734 always valid and contiguous. */
2737 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2739 rtx entry_parm
= data
->entry_parm
;
2740 rtx stack_parm
= data
->stack_parm
;
2742 /* If this parm was passed part in regs and part in memory, pretend it
2743 arrived entirely in memory by pushing the register-part onto the stack.
2744 In the special case of a DImode or DFmode that is split, we could put
2745 it together in a pseudoreg directly, but for now that's not worth
2747 if (data
->partial
!= 0)
2749 /* Handle calls that pass values in multiple non-contiguous
2750 locations. The Irix 6 ABI has examples of this. */
2751 if (GET_CODE (entry_parm
) == PARALLEL
)
2752 emit_group_store (validize_mem (copy_rtx (stack_parm
)), entry_parm
,
2753 data
->arg
.type
, int_size_in_bytes (data
->arg
.type
));
2756 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2757 move_block_from_reg (REGNO (entry_parm
),
2758 validize_mem (copy_rtx (stack_parm
)),
2759 data
->partial
/ UNITS_PER_WORD
);
2762 entry_parm
= stack_parm
;
2765 /* If we didn't decide this parm came in a register, by default it came
2767 else if (entry_parm
== NULL
)
2768 entry_parm
= stack_parm
;
2770 /* When an argument is passed in multiple locations, we can't make use
2771 of this information, but we can save some copying if the whole argument
2772 is passed in a single register. */
2773 else if (GET_CODE (entry_parm
) == PARALLEL
2774 && data
->nominal_mode
!= BLKmode
2775 && data
->passed_mode
!= BLKmode
)
2777 size_t i
, len
= XVECLEN (entry_parm
, 0);
2779 for (i
= 0; i
< len
; i
++)
2780 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2781 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2782 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2783 == data
->passed_mode
)
2784 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2786 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2791 data
->entry_parm
= entry_parm
;
2794 /* A subroutine of assign_parms. Reconstitute any values which were
2795 passed in multiple registers and would fit in a single register. */
2798 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2800 rtx entry_parm
= data
->entry_parm
;
2802 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2803 This can be done with register operations rather than on the
2804 stack, even if we will store the reconstituted parameter on the
2806 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2808 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2809 emit_group_store (parmreg
, entry_parm
, data
->arg
.type
,
2810 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2811 entry_parm
= parmreg
;
2814 data
->entry_parm
= entry_parm
;
2817 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2818 always valid and properly aligned. */
2821 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2823 rtx stack_parm
= data
->stack_parm
;
2825 /* If we can't trust the parm stack slot to be aligned enough for its
2826 ultimate type, don't use that slot after entry. We'll make another
2827 stack slot, if we need one. */
2829 && ((GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
)
2830 && ((optab_handler (movmisalign_optab
, data
->nominal_mode
)
2831 != CODE_FOR_nothing
)
2832 || targetm
.slow_unaligned_access (data
->nominal_mode
,
2833 MEM_ALIGN (stack_parm
))))
2834 || (data
->nominal_type
2835 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2836 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2839 /* If parm was passed in memory, and we need to convert it on entry,
2840 don't store it back in that same slot. */
2841 else if (data
->entry_parm
== stack_parm
2842 && data
->nominal_mode
!= BLKmode
2843 && data
->nominal_mode
!= data
->passed_mode
)
2846 /* If stack protection is in effect for this function, don't leave any
2847 pointers in their passed stack slots. */
2848 else if (crtl
->stack_protect_guard
2849 && (flag_stack_protect
== SPCT_FLAG_ALL
2850 || data
->arg
.pass_by_reference
2851 || POINTER_TYPE_P (data
->nominal_type
)))
2854 data
->stack_parm
= stack_parm
;
2857 /* A subroutine of assign_parms. Return true if the current parameter
2858 should be stored as a BLKmode in the current frame. */
2861 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2863 if (data
->nominal_mode
== BLKmode
)
2865 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2868 #ifdef BLOCK_REG_PADDING
2869 /* Only assign_parm_setup_block knows how to deal with register arguments
2870 that are padded at the least significant end. */
2871 if (REG_P (data
->entry_parm
)
2872 && known_lt (GET_MODE_SIZE (data
->arg
.mode
), UNITS_PER_WORD
)
2873 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->arg
.type
, 1)
2874 == (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
2881 /* A subroutine of assign_parms. Arrange for the parameter to be
2882 present and valid in DATA->STACK_RTL. */
2885 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2886 tree parm
, struct assign_parm_data_one
*data
)
2888 rtx entry_parm
= data
->entry_parm
;
2889 rtx stack_parm
= data
->stack_parm
;
2890 rtx target_reg
= NULL_RTX
;
2891 bool in_conversion_seq
= false;
2893 HOST_WIDE_INT size_stored
;
2895 if (GET_CODE (entry_parm
) == PARALLEL
)
2896 entry_parm
= emit_group_move_into_temps (entry_parm
);
2898 /* If we want the parameter in a pseudo, don't use a stack slot. */
2899 if (is_gimple_reg (parm
) && use_register_for_decl (parm
))
2901 tree def
= ssa_default_def (cfun
, parm
);
2903 machine_mode mode
= promote_ssa_mode (def
, NULL
);
2904 rtx reg
= gen_reg_rtx (mode
);
2905 if (GET_CODE (reg
) != CONCAT
)
2910 /* Avoid allocating a stack slot, if there isn't one
2911 preallocated by the ABI. It might seem like we should
2912 always prefer a pseudo, but converting between
2913 floating-point and integer modes goes through the stack
2914 on various machines, so it's better to use the reserved
2915 stack slot than to risk wasting it and allocating more
2916 for the conversion. */
2917 if (stack_parm
== NULL_RTX
)
2919 int save
= generating_concat_p
;
2920 generating_concat_p
= 0;
2921 stack_parm
= gen_reg_rtx (mode
);
2922 generating_concat_p
= save
;
2925 data
->stack_parm
= NULL
;
2928 size
= int_size_in_bytes (data
->arg
.type
);
2929 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2930 if (stack_parm
== 0)
2932 HOST_WIDE_INT parm_align
2934 ? MAX (DECL_ALIGN (parm
), BITS_PER_WORD
) : DECL_ALIGN (parm
));
2936 SET_DECL_ALIGN (parm
, parm_align
);
2937 if (DECL_ALIGN (parm
) > MAX_SUPPORTED_STACK_ALIGNMENT
)
2939 rtx allocsize
= gen_int_mode (size_stored
, Pmode
);
2940 get_dynamic_stack_size (&allocsize
, 0, DECL_ALIGN (parm
), NULL
);
2941 stack_parm
= assign_stack_local (BLKmode
, UINTVAL (allocsize
),
2942 MAX_SUPPORTED_STACK_ALIGNMENT
);
2943 rtx addr
= align_dynamic_address (XEXP (stack_parm
, 0),
2945 mark_reg_pointer (addr
, DECL_ALIGN (parm
));
2946 stack_parm
= gen_rtx_MEM (GET_MODE (stack_parm
), addr
);
2947 MEM_NOTRAP_P (stack_parm
) = 1;
2950 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2952 if (known_eq (GET_MODE_SIZE (GET_MODE (entry_parm
)), size
))
2953 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2954 set_mem_attributes (stack_parm
, parm
, 1);
2957 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2958 calls that pass values in multiple non-contiguous locations. */
2959 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2963 /* Note that we will be storing an integral number of words.
2964 So we have to be careful to ensure that we allocate an
2965 integral number of words. We do this above when we call
2966 assign_stack_local if space was not allocated in the argument
2967 list. If it was, this will not work if PARM_BOUNDARY is not
2968 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2969 if it becomes a problem. Exception is when BLKmode arrives
2970 with arguments not conforming to word_mode. */
2972 if (data
->stack_parm
== 0)
2974 else if (GET_CODE (entry_parm
) == PARALLEL
)
2977 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2979 mem
= validize_mem (copy_rtx (stack_parm
));
2981 /* Handle values in multiple non-contiguous locations. */
2982 if (GET_CODE (entry_parm
) == PARALLEL
&& !MEM_P (mem
))
2983 emit_group_store (mem
, entry_parm
, data
->arg
.type
, size
);
2984 else if (GET_CODE (entry_parm
) == PARALLEL
)
2986 push_to_sequence2 (all
->first_conversion_insn
,
2987 all
->last_conversion_insn
);
2988 emit_group_store (mem
, entry_parm
, data
->arg
.type
, size
);
2989 all
->first_conversion_insn
= get_insns ();
2990 all
->last_conversion_insn
= get_last_insn ();
2992 in_conversion_seq
= true;
2998 /* If SIZE is that of a mode no bigger than a word, just use
2999 that mode's store operation. */
3000 else if (size
<= UNITS_PER_WORD
)
3002 unsigned int bits
= size
* BITS_PER_UNIT
;
3003 machine_mode mode
= int_mode_for_size (bits
, 0).else_blk ();
3006 #ifdef BLOCK_REG_PADDING
3007 && (size
== UNITS_PER_WORD
3008 || (BLOCK_REG_PADDING (mode
, data
->arg
.type
, 1)
3009 != (BYTES_BIG_ENDIAN
? PAD_UPWARD
: PAD_DOWNWARD
)))
3015 /* We are really truncating a word_mode value containing
3016 SIZE bytes into a value of mode MODE. If such an
3017 operation requires no actual instructions, we can refer
3018 to the value directly in mode MODE, otherwise we must
3019 start with the register in word_mode and explicitly
3021 if (mode
== word_mode
3022 || TRULY_NOOP_TRUNCATION_MODES_P (mode
, word_mode
))
3023 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
3026 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3027 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
3029 emit_move_insn (change_address (mem
, mode
, 0), reg
);
3032 #ifdef BLOCK_REG_PADDING
3033 /* Storing the register in memory as a full word, as
3034 move_block_from_reg below would do, and then using the
3035 MEM in a smaller mode, has the effect of shifting right
3036 if BYTES_BIG_ENDIAN. If we're bypassing memory, the
3037 shifting must be explicit. */
3038 else if (!MEM_P (mem
))
3042 /* If the assert below fails, we should have taken the
3043 mode != BLKmode path above, unless we have downward
3044 padding of smaller-than-word arguments on a machine
3045 with little-endian bytes, which would likely require
3046 additional changes to work correctly. */
3047 gcc_checking_assert (BYTES_BIG_ENDIAN
3048 && (BLOCK_REG_PADDING (mode
,
3052 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3054 x
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3055 x
= expand_shift (RSHIFT_EXPR
, word_mode
, x
, by
,
3057 x
= force_reg (word_mode
, x
);
3058 x
= gen_lowpart_SUBREG (GET_MODE (mem
), x
);
3060 emit_move_insn (mem
, x
);
3064 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
3065 machine must be aligned to the left before storing
3066 to memory. Note that the previous test doesn't
3067 handle all cases (e.g. SIZE == 3). */
3068 else if (size
!= UNITS_PER_WORD
3069 #ifdef BLOCK_REG_PADDING
3070 && (BLOCK_REG_PADDING (mode
, data
->arg
.type
, 1)
3078 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
3079 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
3081 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, by
, NULL_RTX
, 1);
3082 tem
= change_address (mem
, word_mode
, 0);
3083 emit_move_insn (tem
, x
);
3086 move_block_from_reg (REGNO (entry_parm
), mem
,
3087 size_stored
/ UNITS_PER_WORD
);
3089 else if (!MEM_P (mem
))
3091 gcc_checking_assert (size
> UNITS_PER_WORD
);
3092 #ifdef BLOCK_REG_PADDING
3093 gcc_checking_assert (BLOCK_REG_PADDING (GET_MODE (mem
),
3097 emit_move_insn (mem
, entry_parm
);
3100 move_block_from_reg (REGNO (entry_parm
), mem
,
3101 size_stored
/ UNITS_PER_WORD
);
3103 else if (data
->stack_parm
== 0 && !TYPE_EMPTY_P (data
->arg
.type
))
3105 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3106 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
3108 all
->first_conversion_insn
= get_insns ();
3109 all
->last_conversion_insn
= get_last_insn ();
3111 in_conversion_seq
= true;
3116 if (!in_conversion_seq
)
3117 emit_move_insn (target_reg
, stack_parm
);
3120 push_to_sequence2 (all
->first_conversion_insn
,
3121 all
->last_conversion_insn
);
3122 emit_move_insn (target_reg
, stack_parm
);
3123 all
->first_conversion_insn
= get_insns ();
3124 all
->last_conversion_insn
= get_last_insn ();
3127 stack_parm
= target_reg
;
3130 data
->stack_parm
= stack_parm
;
3131 set_parm_rtl (parm
, stack_parm
);
3134 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
3135 parameter. Get it there. Perform all ABI specified conversions. */
3138 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
3139 struct assign_parm_data_one
*data
)
3141 rtx parmreg
, validated_mem
;
3142 rtx equiv_stack_parm
;
3143 machine_mode promoted_nominal_mode
;
3144 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3145 bool did_conversion
= false;
3146 bool need_conversion
, moved
;
3147 enum insn_code icode
;
3150 /* Store the parm in a pseudoregister during the function, but we may
3151 need to do it in a wider mode. Using 2 here makes the result
3152 consistent with promote_decl_mode and thus expand_expr_real_1. */
3153 promoted_nominal_mode
3154 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
3155 TREE_TYPE (current_function_decl
), 2);
3157 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
3158 if (!DECL_ARTIFICIAL (parm
))
3159 mark_user_reg (parmreg
);
3161 /* If this was an item that we received a pointer to,
3162 set rtl appropriately. */
3163 if (data
->arg
.pass_by_reference
)
3165 rtl
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->arg
.type
)), parmreg
);
3166 set_mem_attributes (rtl
, parm
, 1);
3171 assign_parm_remove_parallels (data
);
3173 /* Copy the value into the register, thus bridging between
3174 assign_parm_find_data_types and expand_expr_real_1. */
3176 equiv_stack_parm
= data
->stack_parm
;
3177 validated_mem
= validize_mem (copy_rtx (data
->entry_parm
));
3179 need_conversion
= (data
->nominal_mode
!= data
->passed_mode
3180 || promoted_nominal_mode
!= data
->arg
.mode
);
3184 && GET_MODE_CLASS (data
->nominal_mode
) == MODE_INT
3185 && data
->nominal_mode
== data
->passed_mode
3186 && data
->nominal_mode
== GET_MODE (data
->entry_parm
))
3188 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
3189 mode, by the caller. We now have to convert it to
3190 NOMINAL_MODE, if different. However, PARMREG may be in
3191 a different mode than NOMINAL_MODE if it is being stored
3194 If ENTRY_PARM is a hard register, it might be in a register
3195 not valid for operating in its mode (e.g., an odd-numbered
3196 register for a DFmode). In that case, moves are the only
3197 thing valid, so we can't do a convert from there. This
3198 occurs when the calling sequence allow such misaligned
3201 In addition, the conversion may involve a call, which could
3202 clobber parameters which haven't been copied to pseudo
3205 First, we try to emit an insn which performs the necessary
3206 conversion. We verify that this insn does not clobber any
3211 icode
= can_extend_p (promoted_nominal_mode
, data
->passed_mode
,
3215 op1
= validated_mem
;
3216 if (icode
!= CODE_FOR_nothing
3217 && insn_operand_matches (icode
, 0, op0
)
3218 && insn_operand_matches (icode
, 1, op1
))
3220 enum rtx_code code
= unsignedp
? ZERO_EXTEND
: SIGN_EXTEND
;
3221 rtx_insn
*insn
, *insns
;
3223 HARD_REG_SET hardregs
;
3226 /* If op1 is a hard register that is likely spilled, first
3227 force it into a pseudo, otherwise combiner might extend
3228 its lifetime too much. */
3229 if (GET_CODE (t
) == SUBREG
)
3232 && HARD_REGISTER_P (t
)
3233 && ! TEST_HARD_REG_BIT (fixed_reg_set
, REGNO (t
))
3234 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t
))))
3236 t
= gen_reg_rtx (GET_MODE (op1
));
3237 emit_move_insn (t
, op1
);
3241 rtx_insn
*pat
= gen_extend_insn (op0
, t
, promoted_nominal_mode
,
3242 data
->passed_mode
, unsignedp
);
3244 insns
= get_insns ();
3247 CLEAR_HARD_REG_SET (hardregs
);
3248 for (insn
= insns
; insn
&& moved
; insn
= NEXT_INSN (insn
))
3251 note_stores (insn
, record_hard_reg_sets
, &hardregs
);
3252 if (!hard_reg_set_empty_p (hardregs
))
3261 if (equiv_stack_parm
!= NULL_RTX
)
3262 equiv_stack_parm
= gen_rtx_fmt_e (code
, GET_MODE (parmreg
),
3269 /* Nothing to do. */
3271 else if (need_conversion
)
3273 /* We did not have an insn to convert directly, or the sequence
3274 generated appeared unsafe. We must first copy the parm to a
3275 pseudo reg, and save the conversion until after all
3276 parameters have been moved. */
3279 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3281 emit_move_insn (tempreg
, validated_mem
);
3283 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3284 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
3286 if (partial_subreg_p (tempreg
)
3287 && GET_MODE (tempreg
) == data
->nominal_mode
3288 && REG_P (SUBREG_REG (tempreg
))
3289 && data
->nominal_mode
== data
->passed_mode
3290 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
))
3292 /* The argument is already sign/zero extended, so note it
3294 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
3295 SUBREG_PROMOTED_SET (tempreg
, unsignedp
);
3298 /* TREE_USED gets set erroneously during expand_assignment. */
3299 save_tree_used
= TREE_USED (parm
);
3300 SET_DECL_RTL (parm
, rtl
);
3301 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
3302 SET_DECL_RTL (parm
, NULL_RTX
);
3303 TREE_USED (parm
) = save_tree_used
;
3304 all
->first_conversion_insn
= get_insns ();
3305 all
->last_conversion_insn
= get_last_insn ();
3308 did_conversion
= true;
3310 else if (MEM_P (data
->entry_parm
)
3311 && GET_MODE_ALIGNMENT (promoted_nominal_mode
)
3312 > MEM_ALIGN (data
->entry_parm
)
3313 && (((icode
= optab_handler (movmisalign_optab
,
3314 promoted_nominal_mode
))
3315 != CODE_FOR_nothing
)
3316 || targetm
.slow_unaligned_access (promoted_nominal_mode
,
3317 MEM_ALIGN (data
->entry_parm
))))
3319 if (icode
!= CODE_FOR_nothing
)
3320 emit_insn (GEN_FCN (icode
) (parmreg
, validated_mem
));
3322 rtl
= parmreg
= extract_bit_field (validated_mem
,
3323 GET_MODE_BITSIZE (promoted_nominal_mode
), 0,
3325 promoted_nominal_mode
, VOIDmode
, false, NULL
);
3328 emit_move_insn (parmreg
, validated_mem
);
3330 /* If we were passed a pointer but the actual value can live in a register,
3331 retrieve it and use it directly. Note that we cannot use nominal_mode,
3332 because it will have been set to Pmode above, we must use the actual mode
3333 of the parameter instead. */
3334 if (data
->arg
.pass_by_reference
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
)
3336 /* Use a stack slot for debugging purposes if possible. */
3337 if (use_register_for_decl (parm
))
3339 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
3340 mark_user_reg (parmreg
);
3344 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3345 TYPE_MODE (TREE_TYPE (parm
)),
3346 TYPE_ALIGN (TREE_TYPE (parm
)));
3348 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm
)),
3349 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm
))),
3351 set_mem_attributes (parmreg
, parm
, 1);
3354 /* We need to preserve an address based on VIRTUAL_STACK_VARS_REGNUM for
3355 the debug info in case it is not legitimate. */
3356 if (GET_MODE (parmreg
) != GET_MODE (rtl
))
3358 rtx tempreg
= gen_reg_rtx (GET_MODE (rtl
));
3359 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3361 push_to_sequence2 (all
->first_conversion_insn
,
3362 all
->last_conversion_insn
);
3363 emit_move_insn (tempreg
, rtl
);
3364 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
3365 emit_move_insn (MEM_P (parmreg
) ? copy_rtx (parmreg
) : parmreg
,
3367 all
->first_conversion_insn
= get_insns ();
3368 all
->last_conversion_insn
= get_last_insn ();
3371 did_conversion
= true;
3374 emit_move_insn (MEM_P (parmreg
) ? copy_rtx (parmreg
) : parmreg
, rtl
);
3378 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3380 data
->stack_parm
= NULL
;
3383 set_parm_rtl (parm
, rtl
);
3385 /* Mark the register as eliminable if we did no conversion and it was
3386 copied from memory at a fixed offset, and the arg pointer was not
3387 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3388 offset formed an invalid address, such memory-equivalences as we
3389 make here would screw up life analysis for it. */
3390 if (data
->nominal_mode
== data
->passed_mode
3392 && data
->stack_parm
!= 0
3393 && MEM_P (data
->stack_parm
)
3394 && data
->locate
.offset
.var
== 0
3395 && reg_mentioned_p (virtual_incoming_args_rtx
,
3396 XEXP (data
->stack_parm
, 0)))
3398 rtx_insn
*linsn
= get_last_insn ();
3402 /* Mark complex types separately. */
3403 if (GET_CODE (parmreg
) == CONCAT
)
3405 scalar_mode submode
= GET_MODE_INNER (GET_MODE (parmreg
));
3406 int regnor
= REGNO (XEXP (parmreg
, 0));
3407 int regnoi
= REGNO (XEXP (parmreg
, 1));
3408 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
3409 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
3410 GET_MODE_SIZE (submode
));
3412 /* Scan backwards for the set of the real and
3414 for (sinsn
= linsn
; sinsn
!= 0;
3415 sinsn
= prev_nonnote_insn (sinsn
))
3417 set
= single_set (sinsn
);
3421 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
3422 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
3423 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
3424 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
3428 set_dst_reg_note (linsn
, REG_EQUIV
, equiv_stack_parm
, parmreg
);
3431 /* For pointer data type, suggest pointer register. */
3432 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
3433 mark_reg_pointer (parmreg
,
3434 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
3437 /* A subroutine of assign_parms. Allocate stack space to hold the current
3438 parameter. Get it there. Perform all ABI specified conversions. */
3441 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
3442 struct assign_parm_data_one
*data
)
3444 /* Value must be stored in the stack slot STACK_PARM during function
3446 bool to_conversion
= false;
3448 assign_parm_remove_parallels (data
);
3450 if (data
->arg
.mode
!= data
->nominal_mode
)
3452 /* Conversion is required. */
3453 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3455 emit_move_insn (tempreg
, validize_mem (copy_rtx (data
->entry_parm
)));
3457 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3458 to_conversion
= true;
3460 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
3461 TYPE_UNSIGNED (TREE_TYPE (parm
)));
3463 if (data
->stack_parm
)
3466 = subreg_lowpart_offset (data
->nominal_mode
,
3467 GET_MODE (data
->stack_parm
));
3468 /* ??? This may need a big-endian conversion on sparc64. */
3470 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
3471 if (maybe_ne (offset
, 0) && MEM_OFFSET_KNOWN_P (data
->stack_parm
))
3472 set_mem_offset (data
->stack_parm
,
3473 MEM_OFFSET (data
->stack_parm
) + offset
);
3477 if (data
->entry_parm
!= data
->stack_parm
)
3481 if (data
->stack_parm
== 0)
3483 int align
= STACK_SLOT_ALIGNMENT (data
->arg
.type
,
3484 GET_MODE (data
->entry_parm
),
3485 TYPE_ALIGN (data
->arg
.type
));
3486 if (align
< (int)GET_MODE_ALIGNMENT (GET_MODE (data
->entry_parm
))
3487 && ((optab_handler (movmisalign_optab
,
3488 GET_MODE (data
->entry_parm
))
3489 != CODE_FOR_nothing
)
3490 || targetm
.slow_unaligned_access (GET_MODE (data
->entry_parm
),
3492 align
= GET_MODE_ALIGNMENT (GET_MODE (data
->entry_parm
));
3494 = assign_stack_local (GET_MODE (data
->entry_parm
),
3495 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3497 align
= MEM_ALIGN (data
->stack_parm
);
3498 set_mem_attributes (data
->stack_parm
, parm
, 1);
3499 set_mem_align (data
->stack_parm
, align
);
3502 dest
= validize_mem (copy_rtx (data
->stack_parm
));
3503 src
= validize_mem (copy_rtx (data
->entry_parm
));
3505 if (TYPE_EMPTY_P (data
->arg
.type
))
3506 /* Empty types don't really need to be copied. */;
3507 else if (MEM_P (src
))
3509 /* Use a block move to handle potentially misaligned entry_parm. */
3511 push_to_sequence2 (all
->first_conversion_insn
,
3512 all
->last_conversion_insn
);
3513 to_conversion
= true;
3515 emit_block_move (dest
, src
,
3516 GEN_INT (int_size_in_bytes (data
->arg
.type
)),
3522 src
= force_reg (GET_MODE (src
), src
);
3523 emit_move_insn (dest
, src
);
3529 all
->first_conversion_insn
= get_insns ();
3530 all
->last_conversion_insn
= get_last_insn ();
3534 set_parm_rtl (parm
, data
->stack_parm
);
3537 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3538 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3541 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
,
3545 tree orig_fnargs
= all
->orig_fnargs
;
3548 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
), ++i
)
3550 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3551 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3553 rtx tmp
, real
, imag
;
3554 scalar_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3556 real
= DECL_RTL (fnargs
[i
]);
3557 imag
= DECL_RTL (fnargs
[i
+ 1]);
3558 if (inner
!= GET_MODE (real
))
3560 real
= gen_lowpart_SUBREG (inner
, real
);
3561 imag
= gen_lowpart_SUBREG (inner
, imag
);
3564 if (TREE_ADDRESSABLE (parm
))
3567 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3568 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3570 TYPE_ALIGN (TREE_TYPE (parm
)));
3572 /* split_complex_arg put the real and imag parts in
3573 pseudos. Move them to memory. */
3574 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3575 set_mem_attributes (tmp
, parm
, 1);
3576 rmem
= adjust_address_nv (tmp
, inner
, 0);
3577 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3578 push_to_sequence2 (all
->first_conversion_insn
,
3579 all
->last_conversion_insn
);
3580 emit_move_insn (rmem
, real
);
3581 emit_move_insn (imem
, imag
);
3582 all
->first_conversion_insn
= get_insns ();
3583 all
->last_conversion_insn
= get_last_insn ();
3587 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3588 set_parm_rtl (parm
, tmp
);
3590 real
= DECL_INCOMING_RTL (fnargs
[i
]);
3591 imag
= DECL_INCOMING_RTL (fnargs
[i
+ 1]);
3592 if (inner
!= GET_MODE (real
))
3594 real
= gen_lowpart_SUBREG (inner
, real
);
3595 imag
= gen_lowpart_SUBREG (inner
, imag
);
3597 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3598 set_decl_incoming_rtl (parm
, tmp
, false);
3604 /* Assign RTL expressions to the function's parameters. This may involve
3605 copying them into registers and using those registers as the DECL_RTL. */
3608 assign_parms (tree fndecl
)
3610 struct assign_parm_data_all all
;
3615 crtl
->args
.internal_arg_pointer
3616 = targetm
.calls
.internal_arg_pointer ();
3618 assign_parms_initialize_all (&all
);
3619 fnargs
= assign_parms_augmented_arg_list (&all
);
3621 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3623 struct assign_parm_data_one data
;
3625 /* Extract the type of PARM; adjust it according to ABI. */
3626 assign_parm_find_data_types (&all
, parm
, &data
);
3628 /* Early out for errors and void parameters. */
3629 if (data
.passed_mode
== VOIDmode
)
3631 SET_DECL_RTL (parm
, const0_rtx
);
3632 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3636 /* Estimate stack alignment from parameter alignment. */
3637 if (SUPPORTS_STACK_ALIGNMENT
)
3640 = targetm
.calls
.function_arg_boundary (data
.arg
.mode
,
3642 align
= MINIMUM_ALIGNMENT (data
.arg
.type
, data
.arg
.mode
, align
);
3643 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3644 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3645 TYPE_MODE (data
.nominal_type
),
3646 TYPE_ALIGN (data
.nominal_type
));
3647 if (crtl
->stack_alignment_estimated
< align
)
3649 gcc_assert (!crtl
->stack_realign_processed
);
3650 crtl
->stack_alignment_estimated
= align
;
3654 /* Find out where the parameter arrives in this function. */
3655 assign_parm_find_entry_rtl (&all
, &data
);
3657 /* Find out where stack space for this parameter might be. */
3658 if (assign_parm_is_stack_parm (&all
, &data
))
3660 assign_parm_find_stack_rtl (parm
, &data
);
3661 assign_parm_adjust_entry_rtl (&data
);
3662 /* For arguments that occupy no space in the parameter
3663 passing area, have non-zero size and have address taken,
3664 force creation of a stack slot so that they have distinct
3665 address from other parameters. */
3666 if (TYPE_EMPTY_P (data
.arg
.type
)
3667 && TREE_ADDRESSABLE (parm
)
3668 && data
.entry_parm
== data
.stack_parm
3669 && MEM_P (data
.entry_parm
)
3670 && int_size_in_bytes (data
.arg
.type
))
3671 data
.stack_parm
= NULL_RTX
;
3673 /* Record permanently how this parm was passed. */
3674 if (data
.arg
.pass_by_reference
)
3677 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
.arg
.type
)),
3679 set_decl_incoming_rtl (parm
, incoming_rtl
, true);
3682 set_decl_incoming_rtl (parm
, data
.entry_parm
, false);
3684 assign_parm_adjust_stack_rtl (&data
);
3686 if (assign_parm_setup_block_p (&data
))
3687 assign_parm_setup_block (&all
, parm
, &data
);
3688 else if (data
.arg
.pass_by_reference
|| use_register_for_decl (parm
))
3689 assign_parm_setup_reg (&all
, parm
, &data
);
3691 assign_parm_setup_stack (&all
, parm
, &data
);
3693 if (cfun
->stdarg
&& !DECL_CHAIN (parm
))
3694 assign_parms_setup_varargs (&all
, &data
, false);
3696 /* Update info on where next arg arrives in registers. */
3697 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.arg
);
3700 if (targetm
.calls
.split_complex_arg
)
3701 assign_parms_unsplit_complex (&all
, fnargs
);
3705 /* Output all parameter conversion instructions (possibly including calls)
3706 now that all parameters have been copied out of hard registers. */
3707 emit_insn (all
.first_conversion_insn
);
3709 /* Estimate reload stack alignment from scalar return mode. */
3710 if (SUPPORTS_STACK_ALIGNMENT
)
3712 if (DECL_RESULT (fndecl
))
3714 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3715 machine_mode mode
= TYPE_MODE (type
);
3719 && !AGGREGATE_TYPE_P (type
))
3721 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3722 if (crtl
->stack_alignment_estimated
< align
)
3724 gcc_assert (!crtl
->stack_realign_processed
);
3725 crtl
->stack_alignment_estimated
= align
;
3731 /* If we are receiving a struct value address as the first argument, set up
3732 the RTL for the function result. As this might require code to convert
3733 the transmitted address to Pmode, we do this here to ensure that possible
3734 preliminary conversions of the address have been emitted already. */
3735 if (all
.function_result_decl
)
3737 tree result
= DECL_RESULT (current_function_decl
);
3738 rtx addr
= DECL_RTL (all
.function_result_decl
);
3741 if (DECL_BY_REFERENCE (result
))
3743 SET_DECL_VALUE_EXPR (result
, all
.function_result_decl
);
3748 SET_DECL_VALUE_EXPR (result
,
3749 build1 (INDIRECT_REF
, TREE_TYPE (result
),
3750 all
.function_result_decl
));
3751 addr
= convert_memory_address (Pmode
, addr
);
3752 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3753 set_mem_attributes (x
, result
, 1);
3756 DECL_HAS_VALUE_EXPR_P (result
) = 1;
3758 set_parm_rtl (result
, x
);
3761 /* We have aligned all the args, so add space for the pretend args. */
3762 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3763 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3764 crtl
->args
.size
= all
.stack_args_size
.constant
;
3766 /* Adjust function incoming argument size for alignment and
3769 crtl
->args
.size
= upper_bound (crtl
->args
.size
, all
.reg_parm_stack_space
);
3770 crtl
->args
.size
= aligned_upper_bound (crtl
->args
.size
,
3771 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3773 if (ARGS_GROW_DOWNWARD
)
3775 crtl
->args
.arg_offset_rtx
3776 = (all
.stack_args_size
.var
== 0
3777 ? gen_int_mode (-all
.stack_args_size
.constant
, Pmode
)
3778 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3779 size_int (-all
.stack_args_size
.constant
)),
3780 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3783 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3785 /* See how many bytes, if any, of its args a function should try to pop
3788 crtl
->args
.pops_args
= targetm
.calls
.return_pops_args (fndecl
,
3792 /* For stdarg.h function, save info about
3793 regs and stack space used by the named args. */
3795 crtl
->args
.info
= all
.args_so_far_v
;
3797 /* Set the rtx used for the function return value. Put this in its
3798 own variable so any optimizers that need this information don't have
3799 to include tree.h. Do this here so it gets done when an inlined
3800 function gets output. */
3803 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3804 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3806 /* If scalar return value was computed in a pseudo-reg, or was a named
3807 return value that got dumped to the stack, copy that to the hard
3809 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3811 tree decl_result
= DECL_RESULT (fndecl
);
3812 rtx decl_rtl
= DECL_RTL (decl_result
);
3814 if (REG_P (decl_rtl
)
3815 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3816 : DECL_REGISTER (decl_result
))
3820 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3822 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3823 /* The delay slot scheduler assumes that crtl->return_rtx
3824 holds the hard register containing the return value, not a
3825 temporary pseudo. */
3826 crtl
->return_rtx
= real_decl_rtl
;
3831 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3832 For all seen types, gimplify their sizes. */
3835 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3842 if (POINTER_TYPE_P (t
))
3844 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3845 && !TYPE_SIZES_GIMPLIFIED (t
))
3847 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3855 /* Gimplify the parameter list for current_function_decl. This involves
3856 evaluating SAVE_EXPRs of variable sized parameters and generating code
3857 to implement callee-copies reference parameters. Returns a sequence of
3858 statements to add to the beginning of the function. */
3861 gimplify_parameters (gimple_seq
*cleanup
)
3863 struct assign_parm_data_all all
;
3865 gimple_seq stmts
= NULL
;
3869 assign_parms_initialize_all (&all
);
3870 fnargs
= assign_parms_augmented_arg_list (&all
);
3872 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3874 struct assign_parm_data_one data
;
3876 /* Extract the type of PARM; adjust it according to ABI. */
3877 assign_parm_find_data_types (&all
, parm
, &data
);
3879 /* Early out for errors and void parameters. */
3880 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3883 /* Update info on where next arg arrives in registers. */
3884 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.arg
);
3886 /* ??? Once upon a time variable_size stuffed parameter list
3887 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3888 turned out to be less than manageable in the gimple world.
3889 Now we have to hunt them down ourselves. */
3890 walk_tree_without_duplicates (&data
.arg
.type
,
3891 gimplify_parm_type
, &stmts
);
3893 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3895 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3896 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3899 if (data
.arg
.pass_by_reference
)
3901 tree type
= TREE_TYPE (data
.arg
.type
);
3902 function_arg_info
orig_arg (type
, data
.arg
.named
);
3903 if (reference_callee_copied (&all
.args_so_far_v
, orig_arg
))
3907 /* For constant-sized objects, this is trivial; for
3908 variable-sized objects, we have to play games. */
3909 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3910 && !(flag_stack_check
== GENERIC_STACK_CHECK
3911 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3912 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3914 local
= create_tmp_var (type
, get_name (parm
));
3915 DECL_IGNORED_P (local
) = 0;
3916 /* If PARM was addressable, move that flag over
3917 to the local copy, as its address will be taken,
3918 not the PARMs. Keep the parms address taken
3919 as we'll query that flag during gimplification. */
3920 if (TREE_ADDRESSABLE (parm
))
3921 TREE_ADDRESSABLE (local
) = 1;
3922 if (DECL_NOT_GIMPLE_REG_P (parm
))
3923 DECL_NOT_GIMPLE_REG_P (local
) = 1;
3925 if (!is_gimple_reg (local
)
3926 && flag_stack_reuse
!= SR_NONE
)
3928 tree clobber
= build_clobber (type
);
3929 gimple
*clobber_stmt
;
3930 clobber_stmt
= gimple_build_assign (local
, clobber
);
3931 gimple_seq_add_stmt (cleanup
, clobber_stmt
);
3936 tree ptr_type
, addr
;
3938 ptr_type
= build_pointer_type (type
);
3939 addr
= create_tmp_reg (ptr_type
, get_name (parm
));
3940 DECL_IGNORED_P (addr
) = 0;
3941 local
= build_fold_indirect_ref (addr
);
3943 t
= build_alloca_call_expr (DECL_SIZE_UNIT (parm
),
3945 max_int_size_in_bytes (type
));
3946 /* The call has been built for a variable-sized object. */
3947 CALL_ALLOCA_FOR_VAR_P (t
) = 1;
3948 t
= fold_convert (ptr_type
, t
);
3949 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3950 gimplify_and_add (t
, &stmts
);
3953 gimplify_assign (local
, parm
, &stmts
);
3955 SET_DECL_VALUE_EXPR (parm
, local
);
3956 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3966 /* Compute the size and offset from the start of the stacked arguments for a
3967 parm passed in mode PASSED_MODE and with type TYPE.
3969 INITIAL_OFFSET_PTR points to the current offset into the stacked
3972 The starting offset and size for this parm are returned in
3973 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3974 nonzero, the offset is that of stack slot, which is returned in
3975 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3976 padding required from the initial offset ptr to the stack slot.
3978 IN_REGS is nonzero if the argument will be passed in registers. It will
3979 never be set if REG_PARM_STACK_SPACE is not defined.
3981 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3982 for arguments which are passed in registers.
3984 FNDECL is the function in which the argument was defined.
3986 There are two types of rounding that are done. The first, controlled by
3987 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3988 argument list to be aligned to the specific boundary (in bits). This
3989 rounding affects the initial and starting offsets, but not the argument
3992 The second, controlled by TARGET_FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3993 optionally rounds the size of the parm to PARM_BOUNDARY. The
3994 initial offset is not affected by this rounding, while the size always
3995 is and the starting offset may be. */
3997 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3998 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3999 callers pass in the total size of args so far as
4000 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
4003 locate_and_pad_parm (machine_mode passed_mode
, tree type
, int in_regs
,
4004 int reg_parm_stack_space
, int partial
,
4005 tree fndecl ATTRIBUTE_UNUSED
,
4006 struct args_size
*initial_offset_ptr
,
4007 struct locate_and_pad_arg_data
*locate
)
4010 pad_direction where_pad
;
4011 unsigned int boundary
, round_boundary
;
4012 int part_size_in_regs
;
4014 /* If we have found a stack parm before we reach the end of the
4015 area reserved for registers, skip that area. */
4018 if (reg_parm_stack_space
> 0)
4020 if (initial_offset_ptr
->var
4021 || !ordered_p (initial_offset_ptr
->constant
,
4022 reg_parm_stack_space
))
4024 initial_offset_ptr
->var
4025 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
4026 ssize_int (reg_parm_stack_space
));
4027 initial_offset_ptr
->constant
= 0;
4030 initial_offset_ptr
->constant
4031 = ordered_max (initial_offset_ptr
->constant
,
4032 reg_parm_stack_space
);
4036 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
4039 ? arg_size_in_bytes (type
)
4040 : size_int (GET_MODE_SIZE (passed_mode
)));
4041 where_pad
= targetm
.calls
.function_arg_padding (passed_mode
, type
);
4042 boundary
= targetm
.calls
.function_arg_boundary (passed_mode
, type
);
4043 round_boundary
= targetm
.calls
.function_arg_round_boundary (passed_mode
,
4045 locate
->where_pad
= where_pad
;
4047 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
4048 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
4049 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
4051 locate
->boundary
= boundary
;
4053 if (SUPPORTS_STACK_ALIGNMENT
)
4055 /* stack_alignment_estimated can't change after stack has been
4057 if (crtl
->stack_alignment_estimated
< boundary
)
4059 if (!crtl
->stack_realign_processed
)
4060 crtl
->stack_alignment_estimated
= boundary
;
4063 /* If stack is realigned and stack alignment value
4064 hasn't been finalized, it is OK not to increase
4065 stack_alignment_estimated. The bigger alignment
4066 requirement is recorded in stack_alignment_needed
4068 gcc_assert (!crtl
->stack_realign_finalized
4069 && crtl
->stack_realign_needed
);
4074 if (ARGS_GROW_DOWNWARD
)
4076 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
4077 if (initial_offset_ptr
->var
)
4078 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
4079 initial_offset_ptr
->var
);
4083 if (where_pad
!= PAD_NONE
4084 && (!tree_fits_uhwi_p (sizetree
)
4085 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
4086 s2
= round_up (s2
, round_boundary
/ BITS_PER_UNIT
);
4087 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
4090 locate
->slot_offset
.constant
+= part_size_in_regs
;
4092 if (!in_regs
|| reg_parm_stack_space
> 0)
4093 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
4094 &locate
->alignment_pad
);
4096 locate
->size
.constant
= (-initial_offset_ptr
->constant
4097 - locate
->slot_offset
.constant
);
4098 if (initial_offset_ptr
->var
)
4099 locate
->size
.var
= size_binop (MINUS_EXPR
,
4100 size_binop (MINUS_EXPR
,
4102 initial_offset_ptr
->var
),
4103 locate
->slot_offset
.var
);
4105 /* Pad_below needs the pre-rounded size to know how much to pad
4107 locate
->offset
= locate
->slot_offset
;
4108 if (where_pad
== PAD_DOWNWARD
)
4109 pad_below (&locate
->offset
, passed_mode
, sizetree
);
4114 if (!in_regs
|| reg_parm_stack_space
> 0)
4115 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
4116 &locate
->alignment_pad
);
4117 locate
->slot_offset
= *initial_offset_ptr
;
4119 #ifdef PUSH_ROUNDING
4120 if (passed_mode
!= BLKmode
)
4121 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
4124 /* Pad_below needs the pre-rounded size to know how much to pad below
4125 so this must be done before rounding up. */
4126 locate
->offset
= locate
->slot_offset
;
4127 if (where_pad
== PAD_DOWNWARD
)
4128 pad_below (&locate
->offset
, passed_mode
, sizetree
);
4130 if (where_pad
!= PAD_NONE
4131 && (!tree_fits_uhwi_p (sizetree
)
4132 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
4133 sizetree
= round_up (sizetree
, round_boundary
/ BITS_PER_UNIT
);
4135 ADD_PARM_SIZE (locate
->size
, sizetree
);
4137 locate
->size
.constant
-= part_size_in_regs
;
4140 locate
->offset
.constant
4141 += targetm
.calls
.function_arg_offset (passed_mode
, type
);
4144 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
4145 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
4148 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
4149 struct args_size
*alignment_pad
)
4151 tree save_var
= NULL_TREE
;
4152 poly_int64 save_constant
= 0;
4153 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
4154 poly_int64 sp_offset
= STACK_POINTER_OFFSET
;
4156 #ifdef SPARC_STACK_BOUNDARY_HACK
4157 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
4158 the real alignment of %sp. However, when it does this, the
4159 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
4160 if (SPARC_STACK_BOUNDARY_HACK
)
4164 if (boundary
> PARM_BOUNDARY
)
4166 save_var
= offset_ptr
->var
;
4167 save_constant
= offset_ptr
->constant
;
4170 alignment_pad
->var
= NULL_TREE
;
4171 alignment_pad
->constant
= 0;
4173 if (boundary
> BITS_PER_UNIT
)
4177 || !known_misalignment (offset_ptr
->constant
+ sp_offset
,
4178 boundary_in_bytes
, &misalign
))
4180 tree sp_offset_tree
= ssize_int (sp_offset
);
4181 tree offset
= size_binop (PLUS_EXPR
,
4182 ARGS_SIZE_TREE (*offset_ptr
),
4185 if (ARGS_GROW_DOWNWARD
)
4186 rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
4188 rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
4190 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
4191 /* ARGS_SIZE_TREE includes constant term. */
4192 offset_ptr
->constant
= 0;
4193 if (boundary
> PARM_BOUNDARY
)
4194 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
4199 if (ARGS_GROW_DOWNWARD
)
4200 offset_ptr
->constant
-= misalign
;
4202 offset_ptr
->constant
+= -misalign
& (boundary_in_bytes
- 1);
4204 if (boundary
> PARM_BOUNDARY
)
4205 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
4211 pad_below (struct args_size
*offset_ptr
, machine_mode passed_mode
, tree sizetree
)
4213 unsigned int align
= PARM_BOUNDARY
/ BITS_PER_UNIT
;
4215 if (passed_mode
!= BLKmode
4216 && known_misalignment (GET_MODE_SIZE (passed_mode
), align
, &misalign
))
4217 offset_ptr
->constant
+= -misalign
& (align
- 1);
4220 if (TREE_CODE (sizetree
) != INTEGER_CST
4221 || (TREE_INT_CST_LOW (sizetree
) & (align
- 1)) != 0)
4223 /* Round the size up to multiple of PARM_BOUNDARY bits. */
4224 tree s2
= round_up (sizetree
, align
);
4226 ADD_PARM_SIZE (*offset_ptr
, s2
);
4227 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
4233 /* True if register REGNO was alive at a place where `setjmp' was
4234 called and was set more than once or is an argument. Such regs may
4235 be clobbered by `longjmp'. */
4238 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
4240 /* There appear to be cases where some local vars never reach the
4241 backend but have bogus regnos. */
4242 if (regno
>= max_reg_num ())
4245 return ((REG_N_SETS (regno
) > 1
4246 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun
)),
4248 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
4251 /* Walk the tree of blocks describing the binding levels within a
4252 function and warn about variables the might be killed by setjmp or
4253 vfork. This is done after calling flow_analysis before register
4254 allocation since that will clobber the pseudo-regs to hard
4258 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
4262 for (decl
= BLOCK_VARS (block
); decl
; decl
= DECL_CHAIN (decl
))
4265 && DECL_RTL_SET_P (decl
)
4266 && REG_P (DECL_RTL (decl
))
4267 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4268 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
4269 " %<longjmp%> or %<vfork%>", decl
);
4272 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
4273 setjmp_vars_warning (setjmp_crosses
, sub
);
4276 /* Do the appropriate part of setjmp_vars_warning
4277 but for arguments instead of local variables. */
4280 setjmp_args_warning (bitmap setjmp_crosses
)
4283 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4284 decl
; decl
= DECL_CHAIN (decl
))
4285 if (DECL_RTL (decl
) != 0
4286 && REG_P (DECL_RTL (decl
))
4287 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4288 warning (OPT_Wclobbered
,
4289 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4293 /* Generate warning messages for variables live across setjmp. */
4296 generate_setjmp_warnings (void)
4298 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
4300 if (n_basic_blocks_for_fn (cfun
) == NUM_FIXED_BLOCKS
4301 || bitmap_empty_p (setjmp_crosses
))
4304 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
4305 setjmp_args_warning (setjmp_crosses
);
4309 /* Reverse the order of elements in the fragment chain T of blocks,
4310 and return the new head of the chain (old last element).
4311 In addition to that clear BLOCK_SAME_RANGE flags when needed
4312 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4313 its super fragment origin. */
4316 block_fragments_nreverse (tree t
)
4318 tree prev
= 0, block
, next
, prev_super
= 0;
4319 tree super
= BLOCK_SUPERCONTEXT (t
);
4320 if (BLOCK_FRAGMENT_ORIGIN (super
))
4321 super
= BLOCK_FRAGMENT_ORIGIN (super
);
4322 for (block
= t
; block
; block
= next
)
4324 next
= BLOCK_FRAGMENT_CHAIN (block
);
4325 BLOCK_FRAGMENT_CHAIN (block
) = prev
;
4326 if ((prev
&& !BLOCK_SAME_RANGE (prev
))
4327 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block
))
4329 BLOCK_SAME_RANGE (block
) = 0;
4330 prev_super
= BLOCK_SUPERCONTEXT (block
);
4331 BLOCK_SUPERCONTEXT (block
) = super
;
4334 t
= BLOCK_FRAGMENT_ORIGIN (t
);
4335 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t
))
4337 BLOCK_SAME_RANGE (t
) = 0;
4338 BLOCK_SUPERCONTEXT (t
) = super
;
4342 /* Reverse the order of elements in the chain T of blocks,
4343 and return the new head of the chain (old last element).
4344 Also do the same on subblocks and reverse the order of elements
4345 in BLOCK_FRAGMENT_CHAIN as well. */
4348 blocks_nreverse_all (tree t
)
4350 tree prev
= 0, block
, next
;
4351 for (block
= t
; block
; block
= next
)
4353 next
= BLOCK_CHAIN (block
);
4354 BLOCK_CHAIN (block
) = prev
;
4355 if (BLOCK_FRAGMENT_CHAIN (block
)
4356 && BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
)
4358 BLOCK_FRAGMENT_CHAIN (block
)
4359 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block
));
4360 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block
)))
4361 BLOCK_SAME_RANGE (block
) = 0;
4363 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4370 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4371 and create duplicate blocks. */
4372 /* ??? Need an option to either create block fragments or to create
4373 abstract origin duplicates of a source block. It really depends
4374 on what optimization has been performed. */
4377 reorder_blocks (void)
4379 tree block
= DECL_INITIAL (current_function_decl
);
4381 if (block
== NULL_TREE
)
4384 auto_vec
<tree
, 10> block_stack
;
4386 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4387 clear_block_marks (block
);
4389 /* Prune the old trees away, so that they don't get in the way. */
4390 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
4391 BLOCK_CHAIN (block
) = NULL_TREE
;
4393 /* Recreate the block tree from the note nesting. */
4394 reorder_blocks_1 (get_insns (), block
, &block_stack
);
4395 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4398 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4401 clear_block_marks (tree block
)
4405 TREE_ASM_WRITTEN (block
) = 0;
4406 clear_block_marks (BLOCK_SUBBLOCKS (block
));
4407 block
= BLOCK_CHAIN (block
);
4412 reorder_blocks_1 (rtx_insn
*insns
, tree current_block
,
4413 vec
<tree
> *p_block_stack
)
4416 tree prev_beg
= NULL_TREE
, prev_end
= NULL_TREE
;
4418 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
4422 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
4424 tree block
= NOTE_BLOCK (insn
);
4427 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
);
4431 BLOCK_SAME_RANGE (prev_end
) = 0;
4432 prev_end
= NULL_TREE
;
4434 /* If we have seen this block before, that means it now
4435 spans multiple address regions. Create a new fragment. */
4436 if (TREE_ASM_WRITTEN (block
))
4438 tree new_block
= copy_node (block
);
4440 BLOCK_SAME_RANGE (new_block
) = 0;
4441 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
4442 BLOCK_FRAGMENT_CHAIN (new_block
)
4443 = BLOCK_FRAGMENT_CHAIN (origin
);
4444 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
4446 NOTE_BLOCK (insn
) = new_block
;
4450 if (prev_beg
== current_block
&& prev_beg
)
4451 BLOCK_SAME_RANGE (block
) = 1;
4455 BLOCK_SUBBLOCKS (block
) = 0;
4456 TREE_ASM_WRITTEN (block
) = 1;
4457 /* When there's only one block for the entire function,
4458 current_block == block and we mustn't do this, it
4459 will cause infinite recursion. */
4460 if (block
!= current_block
)
4463 if (block
!= origin
)
4464 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
4465 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4468 if (p_block_stack
->is_empty ())
4469 super
= current_block
;
4472 super
= p_block_stack
->last ();
4473 gcc_assert (super
== current_block
4474 || BLOCK_FRAGMENT_ORIGIN (super
)
4477 BLOCK_SUPERCONTEXT (block
) = super
;
4478 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
4479 BLOCK_SUBBLOCKS (current_block
) = block
;
4480 current_block
= origin
;
4482 p_block_stack
->safe_push (block
);
4484 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
4486 NOTE_BLOCK (insn
) = p_block_stack
->pop ();
4487 current_block
= BLOCK_SUPERCONTEXT (current_block
);
4488 if (BLOCK_FRAGMENT_ORIGIN (current_block
))
4489 current_block
= BLOCK_FRAGMENT_ORIGIN (current_block
);
4490 prev_beg
= NULL_TREE
;
4491 prev_end
= BLOCK_SAME_RANGE (NOTE_BLOCK (insn
))
4492 ? NOTE_BLOCK (insn
) : NULL_TREE
;
4497 prev_beg
= NULL_TREE
;
4499 BLOCK_SAME_RANGE (prev_end
) = 0;
4500 prev_end
= NULL_TREE
;
4505 /* Reverse the order of elements in the chain T of blocks,
4506 and return the new head of the chain (old last element). */
4509 blocks_nreverse (tree t
)
4511 tree prev
= 0, block
, next
;
4512 for (block
= t
; block
; block
= next
)
4514 next
= BLOCK_CHAIN (block
);
4515 BLOCK_CHAIN (block
) = prev
;
4521 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4522 by modifying the last node in chain 1 to point to chain 2. */
4525 block_chainon (tree op1
, tree op2
)
4534 for (t1
= op1
; BLOCK_CHAIN (t1
); t1
= BLOCK_CHAIN (t1
))
4536 BLOCK_CHAIN (t1
) = op2
;
4538 #ifdef ENABLE_TREE_CHECKING
4541 for (t2
= op2
; t2
; t2
= BLOCK_CHAIN (t2
))
4542 gcc_assert (t2
!= t1
);
4549 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4550 non-NULL, list them all into VECTOR, in a depth-first preorder
4551 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4555 all_blocks (tree block
, tree
*vector
)
4561 TREE_ASM_WRITTEN (block
) = 0;
4563 /* Record this block. */
4565 vector
[n_blocks
] = block
;
4569 /* Record the subblocks, and their subblocks... */
4570 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
4571 vector
? vector
+ n_blocks
: 0);
4572 block
= BLOCK_CHAIN (block
);
4578 /* Return a vector containing all the blocks rooted at BLOCK. The
4579 number of elements in the vector is stored in N_BLOCKS_P. The
4580 vector is dynamically allocated; it is the caller's responsibility
4581 to call `free' on the pointer returned. */
4584 get_block_vector (tree block
, int *n_blocks_p
)
4588 *n_blocks_p
= all_blocks (block
, NULL
);
4589 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
4590 all_blocks (block
, block_vector
);
4592 return block_vector
;
4595 static GTY(()) int next_block_index
= 2;
4597 /* Set BLOCK_NUMBER for all the blocks in FN. */
4600 number_blocks (tree fn
)
4606 /* For XCOFF debugging output, we start numbering the blocks
4607 from 1 within each function, rather than keeping a running
4609 #if defined (XCOFF_DEBUGGING_INFO)
4610 if (write_symbols
== XCOFF_DEBUG
)
4611 next_block_index
= 1;
4614 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
4616 /* The top-level BLOCK isn't numbered at all. */
4617 for (i
= 1; i
< n_blocks
; ++i
)
4618 /* We number the blocks from two. */
4619 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
4621 free (block_vector
);
4626 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4629 debug_find_var_in_block_tree (tree var
, tree block
)
4633 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4637 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4639 tree ret
= debug_find_var_in_block_tree (var
, t
);
4647 /* Keep track of whether we're in a dummy function context. If we are,
4648 we don't want to invoke the set_current_function hook, because we'll
4649 get into trouble if the hook calls target_reinit () recursively or
4650 when the initial initialization is not yet complete. */
4652 static bool in_dummy_function
;
4654 /* Invoke the target hook when setting cfun. Update the optimization options
4655 if the function uses different options than the default. */
4658 invoke_set_current_function_hook (tree fndecl
)
4660 if (!in_dummy_function
)
4662 tree opts
= ((fndecl
)
4663 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4664 : optimization_default_node
);
4667 opts
= optimization_default_node
;
4669 /* Change optimization options if needed. */
4670 if (optimization_current_node
!= opts
)
4672 optimization_current_node
= opts
;
4673 cl_optimization_restore (&global_options
, &global_options_set
,
4674 TREE_OPTIMIZATION (opts
));
4677 targetm
.set_current_function (fndecl
);
4678 this_fn_optabs
= this_target_optabs
;
4680 /* Initialize global alignment variables after op. */
4681 parse_alignment_opts ();
4683 if (opts
!= optimization_default_node
)
4685 init_tree_optimization_optabs (opts
);
4686 if (TREE_OPTIMIZATION_OPTABS (opts
))
4687 this_fn_optabs
= (struct target_optabs
*)
4688 TREE_OPTIMIZATION_OPTABS (opts
);
4693 /* cfun should never be set directly; use this function. */
4696 set_cfun (struct function
*new_cfun
, bool force
)
4698 if (cfun
!= new_cfun
|| force
)
4701 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4702 redirect_edge_var_map_empty ();
4706 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4708 static vec
<function
*> cfun_stack
;
4710 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4711 current_function_decl accordingly. */
4714 push_cfun (struct function
*new_cfun
)
4716 gcc_assert ((!cfun
&& !current_function_decl
)
4717 || (cfun
&& current_function_decl
== cfun
->decl
));
4718 cfun_stack
.safe_push (cfun
);
4719 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4720 set_cfun (new_cfun
);
4723 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4728 struct function
*new_cfun
= cfun_stack
.pop ();
4729 /* When in_dummy_function, we do have a cfun but current_function_decl is
4730 NULL. We also allow pushing NULL cfun and subsequently changing
4731 current_function_decl to something else and have both restored by
4733 gcc_checking_assert (in_dummy_function
4735 || current_function_decl
== cfun
->decl
);
4736 set_cfun (new_cfun
);
4737 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4740 /* Return value of funcdef and increase it. */
4742 get_next_funcdef_no (void)
4744 return funcdef_no
++;
4747 /* Return value of funcdef. */
4749 get_last_funcdef_no (void)
4754 /* Allocate and initialize the stack usage info data structure for the
4755 current function. */
4757 allocate_stack_usage_info (void)
4759 gcc_assert (!cfun
->su
);
4760 cfun
->su
= ggc_cleared_alloc
<stack_usage
> ();
4761 cfun
->su
->static_stack_size
= -1;
4764 /* Allocate a function structure for FNDECL and set its contents
4765 to the defaults. Set cfun to the newly-allocated object.
4766 Some of the helper functions invoked during initialization assume
4767 that cfun has already been set. Therefore, assign the new object
4768 directly into cfun and invoke the back end hook explicitly at the
4769 very end, rather than initializing a temporary and calling set_cfun
4772 ABSTRACT_P is true if this is a function that will never be seen by
4773 the middle-end. Such functions are front-end concepts (like C++
4774 function templates) that do not correspond directly to functions
4775 placed in object files. */
4778 allocate_struct_function (tree fndecl
, bool abstract_p
)
4780 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4782 cfun
= ggc_cleared_alloc
<function
> ();
4784 init_eh_for_function ();
4786 if (init_machine_status
)
4787 cfun
->machine
= (*init_machine_status
) ();
4789 #ifdef OVERRIDE_ABI_FORMAT
4790 OVERRIDE_ABI_FORMAT (fndecl
);
4793 if (fndecl
!= NULL_TREE
)
4795 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4796 cfun
->decl
= fndecl
;
4797 current_function_funcdef_no
= get_next_funcdef_no ();
4800 invoke_set_current_function_hook (fndecl
);
4802 if (fndecl
!= NULL_TREE
)
4804 tree result
= DECL_RESULT (fndecl
);
4808 /* Now that we have activated any function-specific attributes
4809 that might affect layout, particularly vector modes, relayout
4810 each of the parameters and the result. */
4811 relayout_decl (result
);
4812 for (tree parm
= DECL_ARGUMENTS (fndecl
); parm
;
4813 parm
= DECL_CHAIN (parm
))
4814 relayout_decl (parm
);
4816 /* Similarly relayout the function decl. */
4817 targetm
.target_option
.relayout_function (fndecl
);
4820 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4822 #ifdef PCC_STATIC_STRUCT_RETURN
4823 cfun
->returns_pcc_struct
= 1;
4825 cfun
->returns_struct
= 1;
4828 cfun
->stdarg
= stdarg_p (fntype
);
4830 /* Assume all registers in stdarg functions need to be saved. */
4831 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4832 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4834 /* ??? This could be set on a per-function basis by the front-end
4835 but is this worth the hassle? */
4836 cfun
->can_throw_non_call_exceptions
= flag_non_call_exceptions
;
4837 cfun
->can_delete_dead_exceptions
= flag_delete_dead_exceptions
;
4839 if (!profile_flag
&& !flag_instrument_function_entry_exit
)
4840 DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (fndecl
) = 1;
4842 if (flag_callgraph_info
)
4843 allocate_stack_usage_info ();
4846 /* Don't enable begin stmt markers if var-tracking at assignments is
4847 disabled. The markers make little sense without the variable
4848 binding annotations among them. */
4849 cfun
->debug_nonbind_markers
= lang_hooks
.emits_begin_stmt
4850 && MAY_HAVE_DEBUG_MARKER_STMTS
;
4853 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4854 instead of just setting it. */
4857 push_struct_function (tree fndecl
)
4859 /* When in_dummy_function we might be in the middle of a pop_cfun and
4860 current_function_decl and cfun may not match. */
4861 gcc_assert (in_dummy_function
4862 || (!cfun
&& !current_function_decl
)
4863 || (cfun
&& current_function_decl
== cfun
->decl
));
4864 cfun_stack
.safe_push (cfun
);
4865 current_function_decl
= fndecl
;
4866 allocate_struct_function (fndecl
, false);
4869 /* Reset crtl and other non-struct-function variables to defaults as
4870 appropriate for emitting rtl at the start of a function. */
4873 prepare_function_start (void)
4875 gcc_assert (!get_last_insn ());
4877 if (in_dummy_function
)
4878 crtl
->abi
= &default_function_abi
;
4880 crtl
->abi
= &fndecl_abi (cfun
->decl
).base_abi ();
4884 init_varasm_status ();
4886 default_rtl_profile ();
4888 if (flag_stack_usage_info
&& !flag_callgraph_info
)
4889 allocate_stack_usage_info ();
4891 cse_not_expected
= ! optimize
;
4893 /* Caller save not needed yet. */
4894 caller_save_needed
= 0;
4896 /* We haven't done register allocation yet. */
4899 /* Indicate that we have not instantiated virtual registers yet. */
4900 virtuals_instantiated
= 0;
4902 /* Indicate that we want CONCATs now. */
4903 generating_concat_p
= 1;
4905 /* Indicate we have no need of a frame pointer yet. */
4906 frame_pointer_needed
= 0;
4910 push_dummy_function (bool with_decl
)
4912 tree fn_decl
, fn_type
, fn_result_decl
;
4914 gcc_assert (!in_dummy_function
);
4915 in_dummy_function
= true;
4919 fn_type
= build_function_type_list (void_type_node
, NULL_TREE
);
4920 fn_decl
= build_decl (UNKNOWN_LOCATION
, FUNCTION_DECL
, NULL_TREE
,
4922 fn_result_decl
= build_decl (UNKNOWN_LOCATION
, RESULT_DECL
,
4923 NULL_TREE
, void_type_node
);
4924 DECL_RESULT (fn_decl
) = fn_result_decl
;
4927 fn_decl
= NULL_TREE
;
4929 push_struct_function (fn_decl
);
4932 /* Initialize the rtl expansion mechanism so that we can do simple things
4933 like generate sequences. This is used to provide a context during global
4934 initialization of some passes. You must call expand_dummy_function_end
4935 to exit this context. */
4938 init_dummy_function_start (void)
4940 push_dummy_function (false);
4941 prepare_function_start ();
4944 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4945 and initialize static variables for generating RTL for the statements
4949 init_function_start (tree subr
)
4951 /* Initialize backend, if needed. */
4954 prepare_function_start ();
4955 decide_function_section (subr
);
4957 /* Warn if this value is an aggregate type,
4958 regardless of which calling convention we are using for it. */
4959 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4960 warning (OPT_Waggregate_return
, "function returns an aggregate");
4963 /* Expand code to verify the stack_protect_guard. This is invoked at
4964 the end of a function to be protected. */
4967 stack_protect_epilogue (void)
4969 tree guard_decl
= crtl
->stack_protect_guard_decl
;
4970 rtx_code_label
*label
= gen_label_rtx ();
4972 rtx_insn
*seq
= NULL
;
4974 x
= expand_normal (crtl
->stack_protect_guard
);
4976 if (targetm
.have_stack_protect_combined_test () && guard_decl
)
4978 gcc_assert (DECL_P (guard_decl
));
4979 y
= DECL_RTL (guard_decl
);
4980 /* Allow the target to compute address of Y and compare it with X without
4981 leaking Y into a register. This combined address + compare pattern
4982 allows the target to prevent spilling of any intermediate results by
4983 splitting it after register allocator. */
4984 seq
= targetm
.gen_stack_protect_combined_test (x
, y
, label
);
4989 y
= expand_normal (guard_decl
);
4993 /* Allow the target to compare Y with X without leaking either into
4995 if (targetm
.have_stack_protect_test ())
4996 seq
= targetm
.gen_stack_protect_test (x
, y
, label
);
5002 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
5004 /* The noreturn predictor has been moved to the tree level. The rtl-level
5005 predictors estimate this branch about 20%, which isn't enough to get
5006 things moved out of line. Since this is the only extant case of adding
5007 a noreturn function at the rtl level, it doesn't seem worth doing ought
5008 except adding the prediction by hand. */
5009 rtx_insn
*tmp
= get_last_insn ();
5011 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
5013 expand_call (targetm
.stack_protect_fail (), NULL_RTX
, /*ignore=*/true);
5018 /* Start the RTL for a new function, and set variables used for
5020 SUBR is the FUNCTION_DECL node.
5021 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
5022 the function's parameters, which must be run at any return statement. */
5025 expand_function_start (tree subr
)
5027 /* Make sure volatile mem refs aren't considered
5028 valid operands of arithmetic insns. */
5029 init_recog_no_volatile ();
5033 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
5036 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
5038 /* Make the label for return statements to jump to. Do not special
5039 case machines with special return instructions -- they will be
5040 handled later during jump, ifcvt, or epilogue creation. */
5041 return_label
= gen_label_rtx ();
5043 /* Initialize rtx used to return the value. */
5044 /* Do this before assign_parms so that we copy the struct value address
5045 before any library calls that assign parms might generate. */
5047 /* Decide whether to return the value in memory or in a register. */
5048 tree res
= DECL_RESULT (subr
);
5049 if (aggregate_value_p (res
, subr
))
5051 /* Returning something that won't go in a register. */
5052 rtx value_address
= 0;
5054 #ifdef PCC_STATIC_STRUCT_RETURN
5055 if (cfun
->returns_pcc_struct
)
5057 int size
= int_size_in_bytes (TREE_TYPE (res
));
5058 value_address
= assemble_static_space (size
);
5063 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
5064 /* Expect to be passed the address of a place to store the value.
5065 If it is passed as an argument, assign_parms will take care of
5069 value_address
= gen_reg_rtx (Pmode
);
5070 emit_move_insn (value_address
, sv
);
5075 rtx x
= value_address
;
5076 if (!DECL_BY_REFERENCE (res
))
5078 x
= gen_rtx_MEM (DECL_MODE (res
), x
);
5079 set_mem_attributes (x
, res
, 1);
5081 set_parm_rtl (res
, x
);
5084 else if (DECL_MODE (res
) == VOIDmode
)
5085 /* If return mode is void, this decl rtl should not be used. */
5086 set_parm_rtl (res
, NULL_RTX
);
5089 /* Compute the return values into a pseudo reg, which we will copy
5090 into the true return register after the cleanups are done. */
5091 tree return_type
= TREE_TYPE (res
);
5093 /* If we may coalesce this result, make sure it has the expected mode
5094 in case it was promoted. But we need not bother about BLKmode. */
5095 machine_mode promoted_mode
5096 = flag_tree_coalesce_vars
&& is_gimple_reg (res
)
5097 ? promote_ssa_mode (ssa_default_def (cfun
, res
), NULL
)
5100 if (promoted_mode
!= BLKmode
)
5101 set_parm_rtl (res
, gen_reg_rtx (promoted_mode
));
5102 else if (TYPE_MODE (return_type
) != BLKmode
5103 && targetm
.calls
.return_in_msb (return_type
))
5104 /* expand_function_end will insert the appropriate padding in
5105 this case. Use the return value's natural (unpadded) mode
5106 within the function proper. */
5107 set_parm_rtl (res
, gen_reg_rtx (TYPE_MODE (return_type
)));
5110 /* In order to figure out what mode to use for the pseudo, we
5111 figure out what the mode of the eventual return register will
5112 actually be, and use that. */
5113 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
5115 /* Structures that are returned in registers are not
5116 aggregate_value_p, so we may see a PARALLEL or a REG. */
5117 if (REG_P (hard_reg
))
5118 set_parm_rtl (res
, gen_reg_rtx (GET_MODE (hard_reg
)));
5121 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
5122 set_parm_rtl (res
, gen_group_rtx (hard_reg
));
5126 /* Set DECL_REGISTER flag so that expand_function_end will copy the
5127 result to the real return register(s). */
5128 DECL_REGISTER (res
) = 1;
5131 /* Initialize rtx for parameters and local variables.
5132 In some cases this requires emitting insns. */
5133 assign_parms (subr
);
5135 /* If function gets a static chain arg, store it. */
5136 if (cfun
->static_chain_decl
)
5138 tree parm
= cfun
->static_chain_decl
;
5143 local
= gen_reg_rtx (promote_decl_mode (parm
, &unsignedp
));
5144 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
5146 set_decl_incoming_rtl (parm
, chain
, false);
5147 set_parm_rtl (parm
, local
);
5148 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
5150 if (GET_MODE (local
) != GET_MODE (chain
))
5152 convert_move (local
, chain
, unsignedp
);
5153 insn
= get_last_insn ();
5156 insn
= emit_move_insn (local
, chain
);
5158 /* Mark the register as eliminable, similar to parameters. */
5160 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
5161 set_dst_reg_note (insn
, REG_EQUIV
, chain
, local
);
5163 /* If we aren't optimizing, save the static chain onto the stack. */
5166 tree saved_static_chain_decl
5167 = build_decl (DECL_SOURCE_LOCATION (parm
), VAR_DECL
,
5168 DECL_NAME (parm
), TREE_TYPE (parm
));
5169 rtx saved_static_chain_rtx
5170 = assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5171 SET_DECL_RTL (saved_static_chain_decl
, saved_static_chain_rtx
);
5172 emit_move_insn (saved_static_chain_rtx
, chain
);
5173 SET_DECL_VALUE_EXPR (parm
, saved_static_chain_decl
);
5174 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
5178 /* The following was moved from init_function_start.
5179 The move was supposed to make sdb output more accurate. */
5180 /* Indicate the beginning of the function body,
5181 as opposed to parm setup. */
5182 emit_note (NOTE_INSN_FUNCTION_BEG
);
5184 gcc_assert (NOTE_P (get_last_insn ()));
5186 parm_birth_insn
= get_last_insn ();
5188 /* If the function receives a non-local goto, then store the
5189 bits we need to restore the frame pointer. */
5190 if (cfun
->nonlocal_goto_save_area
)
5195 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
5196 gcc_assert (DECL_RTL_SET_P (var
));
5198 t_save
= build4 (ARRAY_REF
,
5199 TREE_TYPE (TREE_TYPE (cfun
->nonlocal_goto_save_area
)),
5200 cfun
->nonlocal_goto_save_area
,
5201 integer_zero_node
, NULL_TREE
, NULL_TREE
);
5202 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
5203 gcc_assert (GET_MODE (r_save
) == Pmode
);
5205 emit_move_insn (r_save
, hard_frame_pointer_rtx
);
5206 update_nonlocal_goto_save_area ();
5212 PROFILE_HOOK (current_function_funcdef_no
);
5216 /* If we are doing generic stack checking, the probe should go here. */
5217 if (flag_stack_check
== GENERIC_STACK_CHECK
)
5218 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
5222 pop_dummy_function (void)
5225 in_dummy_function
= false;
5228 /* Undo the effects of init_dummy_function_start. */
5230 expand_dummy_function_end (void)
5232 gcc_assert (in_dummy_function
);
5234 /* End any sequences that failed to be closed due to syntax errors. */
5235 while (in_sequence_p ())
5238 /* Outside function body, can't compute type's actual size
5239 until next function's body starts. */
5241 free_after_parsing (cfun
);
5242 free_after_compilation (cfun
);
5243 pop_dummy_function ();
5246 /* Helper for diddle_return_value. */
5249 diddle_return_value_1 (void (*doit
) (rtx
, void *), void *arg
, rtx outgoing
)
5254 if (REG_P (outgoing
))
5255 (*doit
) (outgoing
, arg
);
5256 else if (GET_CODE (outgoing
) == PARALLEL
)
5260 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
5262 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
5264 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
5270 /* Call DOIT for each hard register used as a return value from
5271 the current function. */
5274 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
5276 diddle_return_value_1 (doit
, arg
, crtl
->return_rtx
);
5280 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
5286 clobber_return_register (void)
5288 diddle_return_value (do_clobber_return_reg
, NULL
);
5290 /* In case we do use pseudo to return value, clobber it too. */
5291 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5293 tree decl_result
= DECL_RESULT (current_function_decl
);
5294 rtx decl_rtl
= DECL_RTL (decl_result
);
5295 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
5297 do_clobber_return_reg (decl_rtl
, NULL
);
5303 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
5309 use_return_register (void)
5311 diddle_return_value (do_use_return_reg
, NULL
);
5314 /* Generate RTL for the end of the current function. */
5317 expand_function_end (void)
5319 /* If arg_pointer_save_area was referenced only from a nested
5320 function, we will not have initialized it yet. Do that now. */
5321 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
5322 get_arg_pointer_save_area ();
5324 /* If we are doing generic stack checking and this function makes calls,
5325 do a stack probe at the start of the function to ensure we have enough
5326 space for another stack frame. */
5327 if (flag_stack_check
== GENERIC_STACK_CHECK
)
5329 rtx_insn
*insn
, *seq
;
5331 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5334 rtx max_frame_size
= GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
);
5336 if (STACK_CHECK_MOVING_SP
)
5337 anti_adjust_stack_and_probe (max_frame_size
, true);
5339 probe_stack_range (STACK_OLD_CHECK_PROTECT
, max_frame_size
);
5342 set_insn_locations (seq
, prologue_location
);
5343 emit_insn_before (seq
, stack_check_probe_note
);
5348 /* End any sequences that failed to be closed due to syntax errors. */
5349 while (in_sequence_p ())
5352 clear_pending_stack_adjust ();
5353 do_pending_stack_adjust ();
5355 /* Output a linenumber for the end of the function.
5356 SDB depended on this. */
5357 set_curr_insn_location (input_location
);
5359 /* Before the return label (if any), clobber the return
5360 registers so that they are not propagated live to the rest of
5361 the function. This can only happen with functions that drop
5362 through; if there had been a return statement, there would
5363 have either been a return rtx, or a jump to the return label.
5365 We delay actual code generation after the current_function_value_rtx
5367 rtx_insn
*clobber_after
= get_last_insn ();
5369 /* Output the label for the actual return from the function. */
5370 emit_label (return_label
);
5372 if (targetm_common
.except_unwind_info (&global_options
) == UI_SJLJ
)
5374 /* Let except.c know where it should emit the call to unregister
5375 the function context for sjlj exceptions. */
5376 if (flag_exceptions
)
5377 sjlj_emit_function_exit_after (get_last_insn ());
5380 /* If this is an implementation of throw, do what's necessary to
5381 communicate between __builtin_eh_return and the epilogue. */
5382 expand_eh_return ();
5384 /* If stack protection is enabled for this function, check the guard. */
5385 if (crtl
->stack_protect_guard
5386 && targetm
.stack_protect_runtime_enabled_p ()
5387 && naked_return_label
== NULL_RTX
)
5388 stack_protect_epilogue ();
5390 /* If scalar return value was computed in a pseudo-reg, or was a named
5391 return value that got dumped to the stack, copy that to the hard
5393 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5395 tree decl_result
= DECL_RESULT (current_function_decl
);
5396 rtx decl_rtl
= DECL_RTL (decl_result
);
5398 if (REG_P (decl_rtl
)
5399 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
5400 : DECL_REGISTER (decl_result
))
5402 rtx real_decl_rtl
= crtl
->return_rtx
;
5405 /* This should be set in assign_parms. */
5406 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
5408 /* If this is a BLKmode structure being returned in registers,
5409 then use the mode computed in expand_return. Note that if
5410 decl_rtl is memory, then its mode may have been changed,
5411 but that crtl->return_rtx has not. */
5412 if (GET_MODE (real_decl_rtl
) == BLKmode
)
5413 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
5415 /* If a non-BLKmode return value should be padded at the least
5416 significant end of the register, shift it left by the appropriate
5417 amount. BLKmode results are handled using the group load/store
5419 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
5420 && REG_P (real_decl_rtl
)
5421 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
5423 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
5424 REGNO (real_decl_rtl
)),
5426 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
5428 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
5430 /* If expand_function_start has created a PARALLEL for decl_rtl,
5431 move the result to the real return registers. Otherwise, do
5432 a group load from decl_rtl for a named return. */
5433 if (GET_CODE (decl_rtl
) == PARALLEL
)
5434 emit_group_move (real_decl_rtl
, decl_rtl
);
5436 emit_group_load (real_decl_rtl
, decl_rtl
,
5437 TREE_TYPE (decl_result
),
5438 int_size_in_bytes (TREE_TYPE (decl_result
)));
5440 /* In the case of complex integer modes smaller than a word, we'll
5441 need to generate some non-trivial bitfield insertions. Do that
5442 on a pseudo and not the hard register. */
5443 else if (GET_CODE (decl_rtl
) == CONCAT
5444 && is_complex_int_mode (GET_MODE (decl_rtl
), &cmode
)
5445 && GET_MODE_BITSIZE (cmode
) <= BITS_PER_WORD
)
5447 int old_generating_concat_p
;
5450 old_generating_concat_p
= generating_concat_p
;
5451 generating_concat_p
= 0;
5452 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
5453 generating_concat_p
= old_generating_concat_p
;
5455 emit_move_insn (tmp
, decl_rtl
);
5456 emit_move_insn (real_decl_rtl
, tmp
);
5458 /* If a named return value dumped decl_return to memory, then
5459 we may need to re-do the PROMOTE_MODE signed/unsigned
5461 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
5463 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
5464 promote_function_mode (TREE_TYPE (decl_result
),
5465 GET_MODE (decl_rtl
), &unsignedp
,
5466 TREE_TYPE (current_function_decl
), 1);
5468 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
5471 emit_move_insn (real_decl_rtl
, decl_rtl
);
5475 /* If returning a structure, arrange to return the address of the value
5476 in a place where debuggers expect to find it.
5478 If returning a structure PCC style,
5479 the caller also depends on this value.
5480 And cfun->returns_pcc_struct is not necessarily set. */
5481 if ((cfun
->returns_struct
|| cfun
->returns_pcc_struct
)
5482 && !targetm
.calls
.omit_struct_return_reg
)
5484 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
5485 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5488 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
5489 type
= TREE_TYPE (type
);
5491 value_address
= XEXP (value_address
, 0);
5493 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
5494 current_function_decl
, true);
5496 /* Mark this as a function return value so integrate will delete the
5497 assignment and USE below when inlining this function. */
5498 REG_FUNCTION_VALUE_P (outgoing
) = 1;
5500 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5501 scalar_int_mode mode
= as_a
<scalar_int_mode
> (GET_MODE (outgoing
));
5502 value_address
= convert_memory_address (mode
, value_address
);
5504 emit_move_insn (outgoing
, value_address
);
5506 /* Show return register used to hold result (in this case the address
5508 crtl
->return_rtx
= outgoing
;
5511 /* Emit the actual code to clobber return register. Don't emit
5512 it if clobber_after is a barrier, then the previous basic block
5513 certainly doesn't fall thru into the exit block. */
5514 if (!BARRIER_P (clobber_after
))
5517 clobber_return_register ();
5518 rtx_insn
*seq
= get_insns ();
5521 emit_insn_after (seq
, clobber_after
);
5524 /* Output the label for the naked return from the function. */
5525 if (naked_return_label
)
5526 emit_label (naked_return_label
);
5528 /* @@@ This is a kludge. We want to ensure that instructions that
5529 may trap are not moved into the epilogue by scheduling, because
5530 we don't always emit unwind information for the epilogue. */
5531 if (cfun
->can_throw_non_call_exceptions
5532 && targetm_common
.except_unwind_info (&global_options
) != UI_SJLJ
)
5533 emit_insn (gen_blockage ());
5535 /* If stack protection is enabled for this function, check the guard. */
5536 if (crtl
->stack_protect_guard
5537 && targetm
.stack_protect_runtime_enabled_p ()
5538 && naked_return_label
)
5539 stack_protect_epilogue ();
5541 /* If we had calls to alloca, and this machine needs
5542 an accurate stack pointer to exit the function,
5543 insert some code to save and restore the stack pointer. */
5544 if (! EXIT_IGNORE_STACK
5545 && cfun
->calls_alloca
)
5550 emit_stack_save (SAVE_FUNCTION
, &tem
);
5551 rtx_insn
*seq
= get_insns ();
5553 emit_insn_before (seq
, parm_birth_insn
);
5555 emit_stack_restore (SAVE_FUNCTION
, tem
);
5558 /* ??? This should no longer be necessary since stupid is no longer with
5559 us, but there are some parts of the compiler (eg reload_combine, and
5560 sh mach_dep_reorg) that still try and compute their own lifetime info
5561 instead of using the general framework. */
5562 use_return_register ();
5566 get_arg_pointer_save_area (void)
5568 rtx ret
= arg_pointer_save_area
;
5572 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5573 arg_pointer_save_area
= ret
;
5576 if (! crtl
->arg_pointer_save_area_init
)
5578 /* Save the arg pointer at the beginning of the function. The
5579 generated stack slot may not be a valid memory address, so we
5580 have to check it and fix it if necessary. */
5582 emit_move_insn (validize_mem (copy_rtx (ret
)),
5583 crtl
->args
.internal_arg_pointer
);
5584 rtx_insn
*seq
= get_insns ();
5587 push_topmost_sequence ();
5588 emit_insn_after (seq
, entry_of_function ());
5589 pop_topmost_sequence ();
5591 crtl
->arg_pointer_save_area_init
= true;
5598 /* If debugging dumps are requested, dump information about how the
5599 target handled -fstack-check=clash for the prologue.
5601 PROBES describes what if any probes were emitted.
5603 RESIDUALS indicates if the prologue had any residual allocation
5604 (i.e. total allocation was not a multiple of PROBE_INTERVAL). */
5607 dump_stack_clash_frame_info (enum stack_clash_probes probes
, bool residuals
)
5614 case NO_PROBE_NO_FRAME
:
5616 "Stack clash no probe no stack adjustment in prologue.\n");
5618 case NO_PROBE_SMALL_FRAME
:
5620 "Stack clash no probe small stack adjustment in prologue.\n");
5623 fprintf (dump_file
, "Stack clash inline probes in prologue.\n");
5626 fprintf (dump_file
, "Stack clash probe loop in prologue.\n");
5631 fprintf (dump_file
, "Stack clash residual allocation in prologue.\n");
5633 fprintf (dump_file
, "Stack clash no residual allocation in prologue.\n");
5635 if (frame_pointer_needed
)
5636 fprintf (dump_file
, "Stack clash frame pointer needed.\n");
5638 fprintf (dump_file
, "Stack clash no frame pointer needed.\n");
5640 if (TREE_THIS_VOLATILE (cfun
->decl
))
5642 "Stack clash noreturn prologue, assuming no implicit"
5643 " probes in caller.\n");
5646 "Stack clash not noreturn prologue.\n");
5649 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5650 for the first time. */
5653 record_insns (rtx_insn
*insns
, rtx end
, hash_table
<insn_cache_hasher
> **hashp
)
5656 hash_table
<insn_cache_hasher
> *hash
= *hashp
;
5659 *hashp
= hash
= hash_table
<insn_cache_hasher
>::create_ggc (17);
5661 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
5663 rtx
*slot
= hash
->find_slot (tmp
, INSERT
);
5664 gcc_assert (*slot
== NULL
);
5669 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5670 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5671 insn, then record COPY as well. */
5674 maybe_copy_prologue_epilogue_insn (rtx insn
, rtx copy
)
5676 hash_table
<insn_cache_hasher
> *hash
;
5679 hash
= epilogue_insn_hash
;
5680 if (!hash
|| !hash
->find (insn
))
5682 hash
= prologue_insn_hash
;
5683 if (!hash
|| !hash
->find (insn
))
5687 slot
= hash
->find_slot (copy
, INSERT
);
5688 gcc_assert (*slot
== NULL
);
5692 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5693 we can be running after reorg, SEQUENCE rtl is possible. */
5696 contains (const rtx_insn
*insn
, hash_table
<insn_cache_hasher
> *hash
)
5701 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5703 rtx_sequence
*seq
= as_a
<rtx_sequence
*> (PATTERN (insn
));
5705 for (i
= seq
->len () - 1; i
>= 0; i
--)
5706 if (hash
->find (seq
->element (i
)))
5711 return hash
->find (const_cast<rtx_insn
*> (insn
)) != NULL
;
5715 prologue_contains (const rtx_insn
*insn
)
5717 return contains (insn
, prologue_insn_hash
);
5721 epilogue_contains (const rtx_insn
*insn
)
5723 return contains (insn
, epilogue_insn_hash
);
5727 prologue_epilogue_contains (const rtx_insn
*insn
)
5729 if (contains (insn
, prologue_insn_hash
))
5731 if (contains (insn
, epilogue_insn_hash
))
5737 record_prologue_seq (rtx_insn
*seq
)
5739 record_insns (seq
, NULL
, &prologue_insn_hash
);
5743 record_epilogue_seq (rtx_insn
*seq
)
5745 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5748 /* Set JUMP_LABEL for a return insn. */
5751 set_return_jump_label (rtx_insn
*returnjump
)
5753 rtx pat
= PATTERN (returnjump
);
5754 if (GET_CODE (pat
) == PARALLEL
)
5755 pat
= XVECEXP (pat
, 0, 0);
5756 if (ANY_RETURN_P (pat
))
5757 JUMP_LABEL (returnjump
) = pat
;
5759 JUMP_LABEL (returnjump
) = ret_rtx
;
5762 /* Return a sequence to be used as the split prologue for the current
5763 function, or NULL. */
5766 make_split_prologue_seq (void)
5768 if (!flag_split_stack
5769 || lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun
->decl
)))
5773 emit_insn (targetm
.gen_split_stack_prologue ());
5774 rtx_insn
*seq
= get_insns ();
5777 record_insns (seq
, NULL
, &prologue_insn_hash
);
5778 set_insn_locations (seq
, prologue_location
);
5783 /* Return a sequence to be used as the prologue for the current function,
5787 make_prologue_seq (void)
5789 if (!targetm
.have_prologue ())
5793 rtx_insn
*seq
= targetm
.gen_prologue ();
5796 /* Insert an explicit USE for the frame pointer
5797 if the profiling is on and the frame pointer is required. */
5798 if (crtl
->profile
&& frame_pointer_needed
)
5799 emit_use (hard_frame_pointer_rtx
);
5801 /* Retain a map of the prologue insns. */
5802 record_insns (seq
, NULL
, &prologue_insn_hash
);
5803 emit_note (NOTE_INSN_PROLOGUE_END
);
5805 /* Ensure that instructions are not moved into the prologue when
5806 profiling is on. The call to the profiling routine can be
5807 emitted within the live range of a call-clobbered register. */
5808 if (!targetm
.profile_before_prologue () && crtl
->profile
)
5809 emit_insn (gen_blockage ());
5813 set_insn_locations (seq
, prologue_location
);
5818 /* Return a sequence to be used as the epilogue for the current function,
5822 make_epilogue_seq (void)
5824 if (!targetm
.have_epilogue ())
5828 emit_note (NOTE_INSN_EPILOGUE_BEG
);
5829 rtx_insn
*seq
= targetm
.gen_epilogue ();
5831 emit_jump_insn (seq
);
5833 /* Retain a map of the epilogue insns. */
5834 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5835 set_insn_locations (seq
, epilogue_location
);
5838 rtx_insn
*returnjump
= get_last_insn ();
5841 if (JUMP_P (returnjump
))
5842 set_return_jump_label (returnjump
);
5848 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5849 this into place with notes indicating where the prologue ends and where
5850 the epilogue begins. Update the basic block information when possible.
5852 Notes on epilogue placement:
5853 There are several kinds of edges to the exit block:
5854 * a single fallthru edge from LAST_BB
5855 * possibly, edges from blocks containing sibcalls
5856 * possibly, fake edges from infinite loops
5858 The epilogue is always emitted on the fallthru edge from the last basic
5859 block in the function, LAST_BB, into the exit block.
5861 If LAST_BB is empty except for a label, it is the target of every
5862 other basic block in the function that ends in a return. If a
5863 target has a return or simple_return pattern (possibly with
5864 conditional variants), these basic blocks can be changed so that a
5865 return insn is emitted into them, and their target is adjusted to
5866 the real exit block.
5868 Notes on shrink wrapping: We implement a fairly conservative
5869 version of shrink-wrapping rather than the textbook one. We only
5870 generate a single prologue and a single epilogue. This is
5871 sufficient to catch a number of interesting cases involving early
5874 First, we identify the blocks that require the prologue to occur before
5875 them. These are the ones that modify a call-saved register, or reference
5876 any of the stack or frame pointer registers. To simplify things, we then
5877 mark everything reachable from these blocks as also requiring a prologue.
5878 This takes care of loops automatically, and avoids the need to examine
5879 whether MEMs reference the frame, since it is sufficient to check for
5880 occurrences of the stack or frame pointer.
5882 We then compute the set of blocks for which the need for a prologue
5883 is anticipatable (borrowing terminology from the shrink-wrapping
5884 description in Muchnick's book). These are the blocks which either
5885 require a prologue themselves, or those that have only successors
5886 where the prologue is anticipatable. The prologue needs to be
5887 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5888 is not. For the moment, we ensure that only one such edge exists.
5890 The epilogue is placed as described above, but we make a
5891 distinction between inserting return and simple_return patterns
5892 when modifying other blocks that end in a return. Blocks that end
5893 in a sibcall omit the sibcall_epilogue if the block is not in
5897 thread_prologue_and_epilogue_insns (void)
5901 /* Can't deal with multiple successors of the entry block at the
5902 moment. Function should always have at least one entry
5904 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun
)));
5906 edge entry_edge
= single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
5907 edge orig_entry_edge
= entry_edge
;
5909 rtx_insn
*split_prologue_seq
= make_split_prologue_seq ();
5910 rtx_insn
*prologue_seq
= make_prologue_seq ();
5911 rtx_insn
*epilogue_seq
= make_epilogue_seq ();
5913 /* Try to perform a kind of shrink-wrapping, making sure the
5914 prologue/epilogue is emitted only around those parts of the
5915 function that require it. */
5916 try_shrink_wrapping (&entry_edge
, prologue_seq
);
5918 /* If the target can handle splitting the prologue/epilogue into separate
5919 components, try to shrink-wrap these components separately. */
5920 try_shrink_wrapping_separate (entry_edge
->dest
);
5922 /* If that did anything for any component we now need the generate the
5923 "main" prologue again. Because some targets require some of these
5924 to be called in a specific order (i386 requires the split prologue
5925 to be first, for example), we create all three sequences again here.
5926 If this does not work for some target, that target should not enable
5927 separate shrink-wrapping. */
5928 if (crtl
->shrink_wrapped_separate
)
5930 split_prologue_seq
= make_split_prologue_seq ();
5931 prologue_seq
= make_prologue_seq ();
5932 epilogue_seq
= make_epilogue_seq ();
5935 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun
));
5937 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5938 this marker for the splits of EH_RETURN patterns, and nothing else
5939 uses the flag in the meantime. */
5940 epilogue_completed
= 1;
5942 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5943 some targets, these get split to a special version of the epilogue
5944 code. In order to be able to properly annotate these with unwind
5945 info, try to split them now. If we get a valid split, drop an
5946 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5949 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
5951 rtx_insn
*prev
, *last
, *trial
;
5953 if (e
->flags
& EDGE_FALLTHRU
)
5955 last
= BB_END (e
->src
);
5956 if (!eh_returnjump_p (last
))
5959 prev
= PREV_INSN (last
);
5960 trial
= try_split (PATTERN (last
), last
, 1);
5964 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
5965 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
5968 edge exit_fallthru_edge
= find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
5970 if (exit_fallthru_edge
)
5974 insert_insn_on_edge (epilogue_seq
, exit_fallthru_edge
);
5975 commit_edge_insertions ();
5977 /* The epilogue insns we inserted may cause the exit edge to no longer
5979 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
5981 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5982 && returnjump_p (BB_END (e
->src
)))
5983 e
->flags
&= ~EDGE_FALLTHRU
;
5986 else if (next_active_insn (BB_END (exit_fallthru_edge
->src
)))
5988 /* We have a fall-through edge to the exit block, the source is not
5989 at the end of the function, and there will be an assembler epilogue
5990 at the end of the function.
5991 We can't use force_nonfallthru here, because that would try to
5992 use return. Inserting a jump 'by hand' is extremely messy, so
5993 we take advantage of cfg_layout_finalize using
5994 fixup_fallthru_exit_predecessor. */
5995 cfg_layout_initialize (0);
5997 FOR_EACH_BB_FN (cur_bb
, cfun
)
5998 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5999 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
6000 cur_bb
->aux
= cur_bb
->next_bb
;
6001 cfg_layout_finalize ();
6005 /* Insert the prologue. */
6007 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
6009 if (split_prologue_seq
|| prologue_seq
)
6011 rtx_insn
*split_prologue_insn
= split_prologue_seq
;
6012 if (split_prologue_seq
)
6014 while (split_prologue_insn
&& !NONDEBUG_INSN_P (split_prologue_insn
))
6015 split_prologue_insn
= NEXT_INSN (split_prologue_insn
);
6016 insert_insn_on_edge (split_prologue_seq
, orig_entry_edge
);
6019 rtx_insn
*prologue_insn
= prologue_seq
;
6022 while (prologue_insn
&& !NONDEBUG_INSN_P (prologue_insn
))
6023 prologue_insn
= NEXT_INSN (prologue_insn
);
6024 insert_insn_on_edge (prologue_seq
, entry_edge
);
6027 commit_edge_insertions ();
6029 /* Look for basic blocks within the prologue insns. */
6030 if (split_prologue_insn
6031 && BLOCK_FOR_INSN (split_prologue_insn
) == NULL
)
6032 split_prologue_insn
= NULL
;
6034 && BLOCK_FOR_INSN (prologue_insn
) == NULL
)
6035 prologue_insn
= NULL
;
6036 if (split_prologue_insn
|| prologue_insn
)
6038 auto_sbitmap
blocks (last_basic_block_for_fn (cfun
));
6039 bitmap_clear (blocks
);
6040 if (split_prologue_insn
)
6041 bitmap_set_bit (blocks
,
6042 BLOCK_FOR_INSN (split_prologue_insn
)->index
);
6044 bitmap_set_bit (blocks
, BLOCK_FOR_INSN (prologue_insn
)->index
);
6045 find_many_sub_basic_blocks (blocks
);
6049 default_rtl_profile ();
6051 /* Emit sibling epilogues before any sibling call sites. */
6052 for (ei
= ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6053 (e
= ei_safe_edge (ei
));
6056 /* Skip those already handled, the ones that run without prologue. */
6057 if (e
->flags
& EDGE_IGNORE
)
6059 e
->flags
&= ~EDGE_IGNORE
;
6063 rtx_insn
*insn
= BB_END (e
->src
);
6065 if (!(CALL_P (insn
) && SIBLING_CALL_P (insn
)))
6068 if (rtx_insn
*ep_seq
= targetm
.gen_sibcall_epilogue ())
6071 emit_note (NOTE_INSN_EPILOGUE_BEG
);
6073 rtx_insn
*seq
= get_insns ();
6076 /* Retain a map of the epilogue insns. Used in life analysis to
6077 avoid getting rid of sibcall epilogue insns. Do this before we
6078 actually emit the sequence. */
6079 record_insns (seq
, NULL
, &epilogue_insn_hash
);
6080 set_insn_locations (seq
, epilogue_location
);
6082 emit_insn_before (seq
, insn
);
6088 rtx_insn
*insn
, *next
;
6090 /* Similarly, move any line notes that appear after the epilogue.
6091 There is no need, however, to be quite so anal about the existence
6092 of such a note. Also possibly move
6093 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6095 for (insn
= epilogue_seq
; insn
; insn
= next
)
6097 next
= NEXT_INSN (insn
);
6099 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
6100 reorder_insns (insn
, insn
, PREV_INSN (epilogue_seq
));
6104 /* Threading the prologue and epilogue changes the artificial refs
6105 in the entry and exit blocks. */
6106 epilogue_completed
= 1;
6107 df_update_entry_exit_and_calls ();
6110 /* Reposition the prologue-end and epilogue-begin notes after
6111 instruction scheduling. */
6114 reposition_prologue_and_epilogue_notes (void)
6116 if (!targetm
.have_prologue ()
6117 && !targetm
.have_epilogue ()
6118 && !targetm
.have_sibcall_epilogue ())
6121 /* Since the hash table is created on demand, the fact that it is
6122 non-null is a signal that it is non-empty. */
6123 if (prologue_insn_hash
!= NULL
)
6125 size_t len
= prologue_insn_hash
->elements ();
6126 rtx_insn
*insn
, *last
= NULL
, *note
= NULL
;
6128 /* Scan from the beginning until we reach the last prologue insn. */
6129 /* ??? While we do have the CFG intact, there are two problems:
6130 (1) The prologue can contain loops (typically probing the stack),
6131 which means that the end of the prologue isn't in the first bb.
6132 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6133 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
6137 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
6140 else if (contains (insn
, prologue_insn_hash
))
6152 /* Scan forward looking for the PROLOGUE_END note. It should
6153 be right at the beginning of the block, possibly with other
6154 insn notes that got moved there. */
6155 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
6158 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
6163 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6165 last
= NEXT_INSN (last
);
6166 reorder_insns (note
, note
, last
);
6170 if (epilogue_insn_hash
!= NULL
)
6175 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6177 rtx_insn
*insn
, *first
= NULL
, *note
= NULL
;
6178 basic_block bb
= e
->src
;
6180 /* Scan from the beginning until we reach the first epilogue insn. */
6181 FOR_BB_INSNS (bb
, insn
)
6185 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
6192 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
6202 /* If the function has a single basic block, and no real
6203 epilogue insns (e.g. sibcall with no cleanup), the
6204 epilogue note can get scheduled before the prologue
6205 note. If we have frame related prologue insns, having
6206 them scanned during the epilogue will result in a crash.
6207 In this case re-order the epilogue note to just before
6208 the last insn in the block. */
6210 first
= BB_END (bb
);
6212 if (PREV_INSN (first
) != note
)
6213 reorder_insns (note
, note
, PREV_INSN (first
));
6219 /* Returns the name of function declared by FNDECL. */
6221 fndecl_name (tree fndecl
)
6225 return lang_hooks
.decl_printable_name (fndecl
, 1);
6228 /* Returns the name of function FN. */
6230 function_name (struct function
*fn
)
6232 tree fndecl
= (fn
== NULL
) ? NULL
: fn
->decl
;
6233 return fndecl_name (fndecl
);
6236 /* Returns the name of the current function. */
6238 current_function_name (void)
6240 return function_name (cfun
);
6245 rest_of_handle_check_leaf_regs (void)
6247 #ifdef LEAF_REGISTERS
6248 crtl
->uses_only_leaf_regs
6249 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
6254 /* Insert a TYPE into the used types hash table of CFUN. */
6257 used_types_insert_helper (tree type
, struct function
*func
)
6259 if (type
!= NULL
&& func
!= NULL
)
6261 if (func
->used_types_hash
== NULL
)
6262 func
->used_types_hash
= hash_set
<tree
>::create_ggc (37);
6264 func
->used_types_hash
->add (type
);
6268 /* Given a type, insert it into the used hash table in cfun. */
6270 used_types_insert (tree t
)
6272 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
6277 if (TREE_CODE (t
) == ERROR_MARK
)
6279 if (TYPE_NAME (t
) == NULL_TREE
6280 || TYPE_NAME (t
) == TYPE_NAME (TYPE_MAIN_VARIANT (t
)))
6281 t
= TYPE_MAIN_VARIANT (t
);
6282 if (debug_info_level
> DINFO_LEVEL_NONE
)
6285 used_types_insert_helper (t
, cfun
);
6288 /* So this might be a type referenced by a global variable.
6289 Record that type so that we can later decide to emit its
6290 debug information. */
6291 vec_safe_push (types_used_by_cur_var_decl
, t
);
6296 /* Helper to Hash a struct types_used_by_vars_entry. */
6299 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
6301 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
6303 return iterative_hash_object (entry
->type
,
6304 iterative_hash_object (entry
->var_decl
, 0));
6307 /* Hash function of the types_used_by_vars_entry hash table. */
6310 used_type_hasher::hash (types_used_by_vars_entry
*entry
)
6312 return hash_types_used_by_vars_entry (entry
);
6315 /*Equality function of the types_used_by_vars_entry hash table. */
6318 used_type_hasher::equal (types_used_by_vars_entry
*e1
,
6319 types_used_by_vars_entry
*e2
)
6321 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
6324 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6327 types_used_by_var_decl_insert (tree type
, tree var_decl
)
6329 if (type
!= NULL
&& var_decl
!= NULL
)
6331 types_used_by_vars_entry
**slot
;
6332 struct types_used_by_vars_entry e
;
6333 e
.var_decl
= var_decl
;
6335 if (types_used_by_vars_hash
== NULL
)
6336 types_used_by_vars_hash
6337 = hash_table
<used_type_hasher
>::create_ggc (37);
6339 slot
= types_used_by_vars_hash
->find_slot (&e
, INSERT
);
6342 struct types_used_by_vars_entry
*entry
;
6343 entry
= ggc_alloc
<types_used_by_vars_entry
> ();
6345 entry
->var_decl
= var_decl
;
6353 const pass_data pass_data_leaf_regs
=
6355 RTL_PASS
, /* type */
6356 "*leaf_regs", /* name */
6357 OPTGROUP_NONE
, /* optinfo_flags */
6358 TV_NONE
, /* tv_id */
6359 0, /* properties_required */
6360 0, /* properties_provided */
6361 0, /* properties_destroyed */
6362 0, /* todo_flags_start */
6363 0, /* todo_flags_finish */
6366 class pass_leaf_regs
: public rtl_opt_pass
6369 pass_leaf_regs (gcc::context
*ctxt
)
6370 : rtl_opt_pass (pass_data_leaf_regs
, ctxt
)
6373 /* opt_pass methods: */
6374 virtual unsigned int execute (function
*)
6376 return rest_of_handle_check_leaf_regs ();
6379 }; // class pass_leaf_regs
6384 make_pass_leaf_regs (gcc::context
*ctxt
)
6386 return new pass_leaf_regs (ctxt
);
6390 rest_of_handle_thread_prologue_and_epilogue (void)
6392 /* prepare_shrink_wrap is sensitive to the block structure of the control
6393 flow graph, so clean it up first. */
6397 /* On some machines, the prologue and epilogue code, or parts thereof,
6398 can be represented as RTL. Doing so lets us schedule insns between
6399 it and the rest of the code and also allows delayed branch
6400 scheduling to operate in the epilogue. */
6401 thread_prologue_and_epilogue_insns ();
6403 /* Some non-cold blocks may now be only reachable from cold blocks.
6405 fixup_partitions ();
6407 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6409 cleanup_cfg (optimize
? CLEANUP_EXPENSIVE
: 0);
6411 /* The stack usage info is finalized during prologue expansion. */
6412 if (flag_stack_usage_info
|| flag_callgraph_info
)
6413 output_stack_usage ();
6418 /* Record a final call to CALLEE at LOCATION. */
6421 record_final_call (tree callee
, location_t location
)
6423 struct callinfo_callee datum
= { location
, callee
};
6424 vec_safe_push (cfun
->su
->callees
, datum
);
6427 /* Record a dynamic allocation made for DECL_OR_EXP. */
6430 record_dynamic_alloc (tree decl_or_exp
)
6432 struct callinfo_dalloc datum
;
6434 if (DECL_P (decl_or_exp
))
6436 datum
.location
= DECL_SOURCE_LOCATION (decl_or_exp
);
6437 const char *name
= lang_hooks
.decl_printable_name (decl_or_exp
, 2);
6438 const char *dot
= strrchr (name
, '.');
6441 datum
.name
= ggc_strdup (name
);
6445 datum
.location
= EXPR_LOCATION (decl_or_exp
);
6449 vec_safe_push (cfun
->su
->dallocs
, datum
);
6454 const pass_data pass_data_thread_prologue_and_epilogue
=
6456 RTL_PASS
, /* type */
6457 "pro_and_epilogue", /* name */
6458 OPTGROUP_NONE
, /* optinfo_flags */
6459 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
6460 0, /* properties_required */
6461 0, /* properties_provided */
6462 0, /* properties_destroyed */
6463 0, /* todo_flags_start */
6464 ( TODO_df_verify
| TODO_df_finish
), /* todo_flags_finish */
6467 class pass_thread_prologue_and_epilogue
: public rtl_opt_pass
6470 pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
6471 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue
, ctxt
)
6474 /* opt_pass methods: */
6475 virtual unsigned int execute (function
*)
6477 return rest_of_handle_thread_prologue_and_epilogue ();
6480 }; // class pass_thread_prologue_and_epilogue
6485 make_pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
6487 return new pass_thread_prologue_and_epilogue (ctxt
);
6491 /* If CONSTRAINT is a matching constraint, then return its number.
6492 Otherwise, return -1. */
6495 matching_constraint_num (const char *constraint
)
6497 if (*constraint
== '%')
6500 if (IN_RANGE (*constraint
, '0', '9'))
6501 return strtoul (constraint
, NULL
, 10);
6506 /* This mini-pass fixes fall-out from SSA in asm statements that have
6507 in-out constraints. Say you start with
6510 asm ("": "+mr" (inout));
6513 which is transformed very early to use explicit output and match operands:
6516 asm ("": "=mr" (inout) : "0" (inout));
6519 Or, after SSA and copyprop,
6521 asm ("": "=mr" (inout_2) : "0" (inout_1));
6524 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6525 they represent two separate values, so they will get different pseudo
6526 registers during expansion. Then, since the two operands need to match
6527 per the constraints, but use different pseudo registers, reload can
6528 only register a reload for these operands. But reloads can only be
6529 satisfied by hardregs, not by memory, so we need a register for this
6530 reload, just because we are presented with non-matching operands.
6531 So, even though we allow memory for this operand, no memory can be
6532 used for it, just because the two operands don't match. This can
6533 cause reload failures on register-starved targets.
6535 So it's a symptom of reload not being able to use memory for reloads
6536 or, alternatively it's also a symptom of both operands not coming into
6537 reload as matching (in which case the pseudo could go to memory just
6538 fine, as the alternative allows it, and no reload would be necessary).
6539 We fix the latter problem here, by transforming
6541 asm ("": "=mr" (inout_2) : "0" (inout_1));
6546 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6549 match_asm_constraints_1 (rtx_insn
*insn
, rtx
*p_sets
, int noutputs
)
6552 bool changed
= false;
6553 rtx op
= SET_SRC (p_sets
[0]);
6554 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
6555 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
6556 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
6558 memset (output_matched
, 0, noutputs
* sizeof (bool));
6559 for (i
= 0; i
< ninputs
; i
++)
6563 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
6566 match
= matching_constraint_num (constraint
);
6570 gcc_assert (match
< noutputs
);
6571 output
= SET_DEST (p_sets
[match
]);
6572 input
= RTVEC_ELT (inputs
, i
);
6573 /* Only do the transformation for pseudos. */
6574 if (! REG_P (output
)
6575 || rtx_equal_p (output
, input
)
6576 || !(REG_P (input
) || SUBREG_P (input
)
6577 || MEM_P (input
) || CONSTANT_P (input
))
6578 || !general_operand (input
, GET_MODE (output
)))
6581 /* We can't do anything if the output is also used as input,
6582 as we're going to overwrite it. */
6583 for (j
= 0; j
< ninputs
; j
++)
6584 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
6589 /* Avoid changing the same input several times. For
6590 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6591 only change it once (to out1), rather than changing it
6592 first to out1 and afterwards to out2. */
6595 for (j
= 0; j
< noutputs
; j
++)
6596 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
6601 output_matched
[match
] = true;
6604 emit_move_insn (output
, copy_rtx (input
));
6605 insns
= get_insns ();
6607 emit_insn_before (insns
, insn
);
6609 constraint
= ASM_OPERANDS_OUTPUT_CONSTRAINT(SET_SRC(p_sets
[match
]));
6610 bool early_clobber_p
= strchr (constraint
, '&') != NULL
;
6612 /* Now replace all mentions of the input with output. We can't
6613 just replace the occurrence in inputs[i], as the register might
6614 also be used in some other input (or even in an address of an
6615 output), which would mean possibly increasing the number of
6616 inputs by one (namely 'output' in addition), which might pose
6617 a too complicated problem for reload to solve. E.g. this situation:
6619 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6621 Here 'input' is used in two occurrences as input (once for the
6622 input operand, once for the address in the second output operand).
6623 If we would replace only the occurrence of the input operand (to
6624 make the matching) we would be left with this:
6627 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6629 Now we suddenly have two different input values (containing the same
6630 value, but different pseudos) where we formerly had only one.
6631 With more complicated asms this might lead to reload failures
6632 which wouldn't have happen without this pass. So, iterate over
6633 all operands and replace all occurrences of the register used.
6635 However, if one or more of the 'input' uses have a non-matching
6636 constraint and the matched output operand is an early clobber
6637 operand, then do not replace the input operand, since by definition
6638 it conflicts with the output operand and cannot share the same
6639 register. See PR89313 for details. */
6641 for (j
= 0; j
< noutputs
; j
++)
6642 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
6643 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
6644 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
6646 for (j
= 0; j
< ninputs
; j
++)
6647 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
6649 if (!early_clobber_p
6650 || match
== matching_constraint_num
6651 (ASM_OPERANDS_INPUT_CONSTRAINT (op
, j
)))
6652 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
6660 df_insn_rescan (insn
);
6663 /* Add the decl D to the local_decls list of FUN. */
6666 add_local_decl (struct function
*fun
, tree d
)
6668 gcc_assert (VAR_P (d
));
6669 vec_safe_push (fun
->local_decls
, d
);
6674 const pass_data pass_data_match_asm_constraints
=
6676 RTL_PASS
, /* type */
6677 "asmcons", /* name */
6678 OPTGROUP_NONE
, /* optinfo_flags */
6679 TV_NONE
, /* tv_id */
6680 0, /* properties_required */
6681 0, /* properties_provided */
6682 0, /* properties_destroyed */
6683 0, /* todo_flags_start */
6684 0, /* todo_flags_finish */
6687 class pass_match_asm_constraints
: public rtl_opt_pass
6690 pass_match_asm_constraints (gcc::context
*ctxt
)
6691 : rtl_opt_pass (pass_data_match_asm_constraints
, ctxt
)
6694 /* opt_pass methods: */
6695 virtual unsigned int execute (function
*);
6697 }; // class pass_match_asm_constraints
6700 pass_match_asm_constraints::execute (function
*fun
)
6707 if (!crtl
->has_asm_statement
)
6710 df_set_flags (DF_DEFER_INSN_RESCAN
);
6711 FOR_EACH_BB_FN (bb
, fun
)
6713 FOR_BB_INSNS (bb
, insn
)
6718 pat
= PATTERN (insn
);
6719 if (GET_CODE (pat
) == PARALLEL
)
6720 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
6721 else if (GET_CODE (pat
) == SET
)
6722 p_sets
= &PATTERN (insn
), noutputs
= 1;
6726 if (GET_CODE (*p_sets
) == SET
6727 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
6728 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
6732 return TODO_df_finish
;
6738 make_pass_match_asm_constraints (gcc::context
*ctxt
)
6740 return new pass_match_asm_constraints (ctxt
);
6744 #include "gt-function.h"