1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987-2014 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"
38 #include "rtl-error.h"
40 #include "stor-layout.h"
42 #include "stringpool.h"
50 #include "hard-reg-set.h"
51 #include "insn-config.h"
56 #include "langhooks.h"
58 #include "common/common-target.h"
59 #include "gimple-expr.h"
61 #include "tree-pass.h"
65 #include "bb-reorder.h"
67 /* So we can assign to cfun in this file. */
70 #ifndef STACK_ALIGNMENT_NEEDED
71 #define STACK_ALIGNMENT_NEEDED 1
74 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
76 /* Round a value to the lowest integer less than it that is a multiple of
77 the required alignment. Avoid using division in case the value is
78 negative. Assume the alignment is a power of two. */
79 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
81 /* Similar, but round to the next highest integer that meets the
83 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
85 /* Nonzero once virtual register instantiation has been done.
86 assign_stack_local uses frame_pointer_rtx when this is nonzero.
87 calls.c:emit_library_call_value_1 uses it to set up
88 post-instantiation libcalls. */
89 int virtuals_instantiated
;
91 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
92 static GTY(()) int funcdef_no
;
94 /* These variables hold pointers to functions to create and destroy
95 target specific, per-function data structures. */
96 struct machine_function
* (*init_machine_status
) (void);
98 /* The currently compiled function. */
99 struct function
*cfun
= 0;
101 /* These hashes record the prologue and epilogue insns. */
102 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
103 htab_t prologue_insn_hash
;
104 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
105 htab_t epilogue_insn_hash
;
108 htab_t types_used_by_vars_hash
= NULL
;
109 vec
<tree
, va_gc
> *types_used_by_cur_var_decl
;
111 /* Forward declarations. */
113 static struct temp_slot
*find_temp_slot_from_address (rtx
);
114 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
115 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
116 static void reorder_blocks_1 (rtx
, tree
, vec
<tree
> *);
117 static int all_blocks (tree
, tree
*);
118 static tree
*get_block_vector (tree
, int *);
119 extern tree
debug_find_var_in_block_tree (tree
, tree
);
120 /* We always define `record_insns' even if it's not used so that we
121 can always export `prologue_epilogue_contains'. */
122 static void record_insns (rtx
, rtx
, htab_t
*) ATTRIBUTE_UNUSED
;
123 static bool contains (const_rtx
, htab_t
);
124 static void prepare_function_start (void);
125 static void do_clobber_return_reg (rtx
, void *);
126 static void do_use_return_reg (rtx
, void *);
128 /* Stack of nested functions. */
129 /* Keep track of the cfun stack. */
131 typedef struct function
*function_p
;
133 static vec
<function_p
> function_context_stack
;
135 /* Save the current context for compilation of a nested function.
136 This is called from language-specific code. */
139 push_function_context (void)
142 allocate_struct_function (NULL
, false);
144 function_context_stack
.safe_push (cfun
);
148 /* Restore the last saved context, at the end of a nested function.
149 This function is called from language-specific code. */
152 pop_function_context (void)
154 struct function
*p
= function_context_stack
.pop ();
156 current_function_decl
= p
->decl
;
158 /* Reset variables that have known state during rtx generation. */
159 virtuals_instantiated
= 0;
160 generating_concat_p
= 1;
163 /* Clear out all parts of the state in F that can safely be discarded
164 after the function has been parsed, but not compiled, to let
165 garbage collection reclaim the memory. */
168 free_after_parsing (struct function
*f
)
173 /* Clear out all parts of the state in F that can safely be discarded
174 after the function has been compiled, to let garbage collection
175 reclaim the memory. */
178 free_after_compilation (struct function
*f
)
180 prologue_insn_hash
= NULL
;
181 epilogue_insn_hash
= NULL
;
183 free (crtl
->emit
.regno_pointer_align
);
185 memset (crtl
, 0, sizeof (struct rtl_data
));
190 regno_reg_rtx
= NULL
;
193 /* Return size needed for stack frame based on slots so far allocated.
194 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
195 the caller may have to do that. */
198 get_frame_size (void)
200 if (FRAME_GROWS_DOWNWARD
)
201 return -frame_offset
;
206 /* Issue an error message and return TRUE if frame OFFSET overflows in
207 the signed target pointer arithmetics for function FUNC. Otherwise
211 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
213 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
215 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
216 /* Leave room for the fixed part of the frame. */
217 - 64 * UNITS_PER_WORD
)
219 error_at (DECL_SOURCE_LOCATION (func
),
220 "total size of local objects too large");
227 /* Return stack slot alignment in bits for TYPE and MODE. */
230 get_stack_local_alignment (tree type
, enum machine_mode mode
)
232 unsigned int alignment
;
235 alignment
= BIGGEST_ALIGNMENT
;
237 alignment
= GET_MODE_ALIGNMENT (mode
);
239 /* Allow the frond-end to (possibly) increase the alignment of this
242 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
244 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
247 /* Determine whether it is possible to fit a stack slot of size SIZE and
248 alignment ALIGNMENT into an area in the stack frame that starts at
249 frame offset START and has a length of LENGTH. If so, store the frame
250 offset to be used for the stack slot in *POFFSET and return true;
251 return false otherwise. This function will extend the frame size when
252 given a start/length pair that lies at the end of the frame. */
255 try_fit_stack_local (HOST_WIDE_INT start
, HOST_WIDE_INT length
,
256 HOST_WIDE_INT size
, unsigned int alignment
,
257 HOST_WIDE_INT
*poffset
)
259 HOST_WIDE_INT this_frame_offset
;
260 int frame_off
, frame_alignment
, frame_phase
;
262 /* Calculate how many bytes the start of local variables is off from
264 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
265 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
266 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
268 /* Round the frame offset to the specified alignment. */
270 /* We must be careful here, since FRAME_OFFSET might be negative and
271 division with a negative dividend isn't as well defined as we might
272 like. So we instead assume that ALIGNMENT is a power of two and
273 use logical operations which are unambiguous. */
274 if (FRAME_GROWS_DOWNWARD
)
276 = (FLOOR_ROUND (start
+ length
- size
- frame_phase
,
277 (unsigned HOST_WIDE_INT
) alignment
)
281 = (CEIL_ROUND (start
- frame_phase
,
282 (unsigned HOST_WIDE_INT
) alignment
)
285 /* See if it fits. If this space is at the edge of the frame,
286 consider extending the frame to make it fit. Our caller relies on
287 this when allocating a new slot. */
288 if (frame_offset
== start
&& this_frame_offset
< frame_offset
)
289 frame_offset
= this_frame_offset
;
290 else if (this_frame_offset
< start
)
292 else if (start
+ length
== frame_offset
293 && this_frame_offset
+ size
> start
+ length
)
294 frame_offset
= this_frame_offset
+ size
;
295 else if (this_frame_offset
+ size
> start
+ length
)
298 *poffset
= this_frame_offset
;
302 /* Create a new frame_space structure describing free space in the stack
303 frame beginning at START and ending at END, and chain it into the
304 function's frame_space_list. */
307 add_frame_space (HOST_WIDE_INT start
, HOST_WIDE_INT end
)
309 struct frame_space
*space
= ggc_alloc_frame_space ();
310 space
->next
= crtl
->frame_space_list
;
311 crtl
->frame_space_list
= space
;
312 space
->start
= start
;
313 space
->length
= end
- start
;
316 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
317 with machine mode MODE.
319 ALIGN controls the amount of alignment for the address of the slot:
320 0 means according to MODE,
321 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
322 -2 means use BITS_PER_UNIT,
323 positive specifies alignment boundary in bits.
325 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
326 alignment and ASLK_RECORD_PAD bit set if we should remember
327 extra space we allocated for alignment purposes. When we are
328 called from assign_stack_temp_for_type, it is not set so we don't
329 track the same stack slot in two independent lists.
331 We do not round to stack_boundary here. */
334 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
338 int bigend_correction
= 0;
339 HOST_WIDE_INT slot_offset
= 0, old_frame_offset
;
340 unsigned int alignment
, alignment_in_bits
;
344 alignment
= get_stack_local_alignment (NULL
, mode
);
345 alignment
/= BITS_PER_UNIT
;
347 else if (align
== -1)
349 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
350 size
= CEIL_ROUND (size
, alignment
);
352 else if (align
== -2)
353 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
355 alignment
= align
/ BITS_PER_UNIT
;
357 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
359 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
360 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
362 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
363 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
366 if (SUPPORTS_STACK_ALIGNMENT
)
368 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
370 if (!crtl
->stack_realign_processed
)
371 crtl
->stack_alignment_estimated
= alignment_in_bits
;
374 /* If stack is realigned and stack alignment value
375 hasn't been finalized, it is OK not to increase
376 stack_alignment_estimated. The bigger alignment
377 requirement is recorded in stack_alignment_needed
379 gcc_assert (!crtl
->stack_realign_finalized
);
380 if (!crtl
->stack_realign_needed
)
382 /* It is OK to reduce the alignment as long as the
383 requested size is 0 or the estimated stack
384 alignment >= mode alignment. */
385 gcc_assert ((kind
& ASLK_REDUCE_ALIGN
)
387 || (crtl
->stack_alignment_estimated
388 >= GET_MODE_ALIGNMENT (mode
)));
389 alignment_in_bits
= crtl
->stack_alignment_estimated
;
390 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
396 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
397 crtl
->stack_alignment_needed
= alignment_in_bits
;
398 if (crtl
->max_used_stack_slot_alignment
< alignment_in_bits
)
399 crtl
->max_used_stack_slot_alignment
= alignment_in_bits
;
401 if (mode
!= BLKmode
|| size
!= 0)
403 if (kind
& ASLK_RECORD_PAD
)
405 struct frame_space
**psp
;
407 for (psp
= &crtl
->frame_space_list
; *psp
; psp
= &(*psp
)->next
)
409 struct frame_space
*space
= *psp
;
410 if (!try_fit_stack_local (space
->start
, space
->length
, size
,
411 alignment
, &slot_offset
))
414 if (slot_offset
> space
->start
)
415 add_frame_space (space
->start
, slot_offset
);
416 if (slot_offset
+ size
< space
->start
+ space
->length
)
417 add_frame_space (slot_offset
+ size
,
418 space
->start
+ space
->length
);
423 else if (!STACK_ALIGNMENT_NEEDED
)
425 slot_offset
= frame_offset
;
429 old_frame_offset
= frame_offset
;
431 if (FRAME_GROWS_DOWNWARD
)
433 frame_offset
-= size
;
434 try_fit_stack_local (frame_offset
, size
, size
, alignment
, &slot_offset
);
436 if (kind
& ASLK_RECORD_PAD
)
438 if (slot_offset
> frame_offset
)
439 add_frame_space (frame_offset
, slot_offset
);
440 if (slot_offset
+ size
< old_frame_offset
)
441 add_frame_space (slot_offset
+ size
, old_frame_offset
);
446 frame_offset
+= size
;
447 try_fit_stack_local (old_frame_offset
, size
, size
, alignment
, &slot_offset
);
449 if (kind
& ASLK_RECORD_PAD
)
451 if (slot_offset
> old_frame_offset
)
452 add_frame_space (old_frame_offset
, slot_offset
);
453 if (slot_offset
+ size
< frame_offset
)
454 add_frame_space (slot_offset
+ size
, frame_offset
);
459 /* On a big-endian machine, if we are allocating more space than we will use,
460 use the least significant bytes of those that are allocated. */
461 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
462 bigend_correction
= size
- GET_MODE_SIZE (mode
);
464 /* If we have already instantiated virtual registers, return the actual
465 address relative to the frame pointer. */
466 if (virtuals_instantiated
)
467 addr
= plus_constant (Pmode
, frame_pointer_rtx
,
469 (slot_offset
+ bigend_correction
470 + STARTING_FRAME_OFFSET
, Pmode
));
472 addr
= plus_constant (Pmode
, virtual_stack_vars_rtx
,
474 (slot_offset
+ bigend_correction
,
477 x
= gen_rtx_MEM (mode
, addr
);
478 set_mem_align (x
, alignment_in_bits
);
479 MEM_NOTRAP_P (x
) = 1;
482 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
484 if (frame_offset_overflow (frame_offset
, current_function_decl
))
490 /* Wrap up assign_stack_local_1 with last parameter as false. */
493 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
495 return assign_stack_local_1 (mode
, size
, align
, ASLK_RECORD_PAD
);
498 /* In order to evaluate some expressions, such as function calls returning
499 structures in memory, we need to temporarily allocate stack locations.
500 We record each allocated temporary in the following structure.
502 Associated with each temporary slot is a nesting level. When we pop up
503 one level, all temporaries associated with the previous level are freed.
504 Normally, all temporaries are freed after the execution of the statement
505 in which they were created. However, if we are inside a ({...}) grouping,
506 the result may be in a temporary and hence must be preserved. If the
507 result could be in a temporary, we preserve it if we can determine which
508 one it is in. If we cannot determine which temporary may contain the
509 result, all temporaries are preserved. A temporary is preserved by
510 pretending it was allocated at the previous nesting level. */
512 struct GTY(()) temp_slot
{
513 /* Points to next temporary slot. */
514 struct temp_slot
*next
;
515 /* Points to previous temporary slot. */
516 struct temp_slot
*prev
;
517 /* The rtx to used to reference the slot. */
519 /* The size, in units, of the slot. */
521 /* The type of the object in the slot, or zero if it doesn't correspond
522 to a type. We use this to determine whether a slot can be reused.
523 It can be reused if objects of the type of the new slot will always
524 conflict with objects of the type of the old slot. */
526 /* The alignment (in bits) of the slot. */
528 /* Nonzero if this temporary is currently in use. */
530 /* Nesting level at which this slot is being used. */
532 /* The offset of the slot from the frame_pointer, including extra space
533 for alignment. This info is for combine_temp_slots. */
534 HOST_WIDE_INT base_offset
;
535 /* The size of the slot, including extra space for alignment. This
536 info is for combine_temp_slots. */
537 HOST_WIDE_INT full_size
;
540 /* A table of addresses that represent a stack slot. The table is a mapping
541 from address RTXen to a temp slot. */
542 static GTY((param_is(struct temp_slot_address_entry
))) htab_t temp_slot_address_table
;
543 static size_t n_temp_slots_in_use
;
545 /* Entry for the above hash table. */
546 struct GTY(()) temp_slot_address_entry
{
549 struct temp_slot
*temp_slot
;
552 /* Removes temporary slot TEMP from LIST. */
555 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
558 temp
->next
->prev
= temp
->prev
;
560 temp
->prev
->next
= temp
->next
;
564 temp
->prev
= temp
->next
= NULL
;
567 /* Inserts temporary slot TEMP to LIST. */
570 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
574 (*list
)->prev
= temp
;
579 /* Returns the list of used temp slots at LEVEL. */
581 static struct temp_slot
**
582 temp_slots_at_level (int level
)
584 if (level
>= (int) vec_safe_length (used_temp_slots
))
585 vec_safe_grow_cleared (used_temp_slots
, level
+ 1);
587 return &(*used_temp_slots
)[level
];
590 /* Returns the maximal temporary slot level. */
593 max_slot_level (void)
595 if (!used_temp_slots
)
598 return used_temp_slots
->length () - 1;
601 /* Moves temporary slot TEMP to LEVEL. */
604 move_slot_to_level (struct temp_slot
*temp
, int level
)
606 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
607 insert_slot_to_list (temp
, temp_slots_at_level (level
));
611 /* Make temporary slot TEMP available. */
614 make_slot_available (struct temp_slot
*temp
)
616 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
617 insert_slot_to_list (temp
, &avail_temp_slots
);
620 n_temp_slots_in_use
--;
623 /* Compute the hash value for an address -> temp slot mapping.
624 The value is cached on the mapping entry. */
626 temp_slot_address_compute_hash (struct temp_slot_address_entry
*t
)
628 int do_not_record
= 0;
629 return hash_rtx (t
->address
, GET_MODE (t
->address
),
630 &do_not_record
, NULL
, false);
633 /* Return the hash value for an address -> temp slot mapping. */
635 temp_slot_address_hash (const void *p
)
637 const struct temp_slot_address_entry
*t
;
638 t
= (const struct temp_slot_address_entry
*) p
;
642 /* Compare two address -> temp slot mapping entries. */
644 temp_slot_address_eq (const void *p1
, const void *p2
)
646 const struct temp_slot_address_entry
*t1
, *t2
;
647 t1
= (const struct temp_slot_address_entry
*) p1
;
648 t2
= (const struct temp_slot_address_entry
*) p2
;
649 return exp_equiv_p (t1
->address
, t2
->address
, 0, true);
652 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
654 insert_temp_slot_address (rtx address
, struct temp_slot
*temp_slot
)
657 struct temp_slot_address_entry
*t
= ggc_alloc_temp_slot_address_entry ();
658 t
->address
= address
;
659 t
->temp_slot
= temp_slot
;
660 t
->hash
= temp_slot_address_compute_hash (t
);
661 slot
= htab_find_slot_with_hash (temp_slot_address_table
, t
, t
->hash
, INSERT
);
665 /* Remove an address -> temp slot mapping entry if the temp slot is
666 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
668 remove_unused_temp_slot_addresses_1 (void **slot
, void *data ATTRIBUTE_UNUSED
)
670 const struct temp_slot_address_entry
*t
;
671 t
= (const struct temp_slot_address_entry
*) *slot
;
672 if (! t
->temp_slot
->in_use
)
673 htab_clear_slot (temp_slot_address_table
, slot
);
677 /* Remove all mappings of addresses to unused temp slots. */
679 remove_unused_temp_slot_addresses (void)
681 /* Use quicker clearing if there aren't any active temp slots. */
682 if (n_temp_slots_in_use
)
683 htab_traverse (temp_slot_address_table
,
684 remove_unused_temp_slot_addresses_1
,
687 htab_empty (temp_slot_address_table
);
690 /* Find the temp slot corresponding to the object at address X. */
692 static struct temp_slot
*
693 find_temp_slot_from_address (rtx x
)
696 struct temp_slot_address_entry tmp
, *t
;
698 /* First try the easy way:
699 See if X exists in the address -> temp slot mapping. */
701 tmp
.temp_slot
= NULL
;
702 tmp
.hash
= temp_slot_address_compute_hash (&tmp
);
703 t
= (struct temp_slot_address_entry
*)
704 htab_find_with_hash (temp_slot_address_table
, &tmp
, tmp
.hash
);
708 /* If we have a sum involving a register, see if it points to a temp
710 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
711 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
713 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
714 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
717 /* Last resort: Address is a virtual stack var address. */
718 if (GET_CODE (x
) == PLUS
719 && XEXP (x
, 0) == virtual_stack_vars_rtx
720 && CONST_INT_P (XEXP (x
, 1)))
723 for (i
= max_slot_level (); i
>= 0; i
--)
724 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
726 if (INTVAL (XEXP (x
, 1)) >= p
->base_offset
727 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
)
735 /* Allocate a temporary stack slot and record it for possible later
738 MODE is the machine mode to be given to the returned rtx.
740 SIZE is the size in units of the space required. We do no rounding here
741 since assign_stack_local will do any required rounding.
743 TYPE is the type that will be used for the stack slot. */
746 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
750 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
753 /* If SIZE is -1 it means that somebody tried to allocate a temporary
754 of a variable size. */
755 gcc_assert (size
!= -1);
757 align
= get_stack_local_alignment (type
, mode
);
759 /* Try to find an available, already-allocated temporary of the proper
760 mode which meets the size and alignment requirements. Choose the
761 smallest one with the closest alignment.
763 If assign_stack_temp is called outside of the tree->rtl expansion,
764 we cannot reuse the stack slots (that may still refer to
765 VIRTUAL_STACK_VARS_REGNUM). */
766 if (!virtuals_instantiated
)
768 for (p
= avail_temp_slots
; p
; p
= p
->next
)
770 if (p
->align
>= align
&& p
->size
>= size
771 && GET_MODE (p
->slot
) == mode
772 && objects_must_conflict_p (p
->type
, type
)
773 && (best_p
== 0 || best_p
->size
> p
->size
774 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
776 if (p
->align
== align
&& p
->size
== size
)
779 cut_slot_from_list (selected
, &avail_temp_slots
);
788 /* Make our best, if any, the one to use. */
792 cut_slot_from_list (selected
, &avail_temp_slots
);
794 /* If there are enough aligned bytes left over, make them into a new
795 temp_slot so that the extra bytes don't get wasted. Do this only
796 for BLKmode slots, so that we can be sure of the alignment. */
797 if (GET_MODE (best_p
->slot
) == BLKmode
)
799 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
800 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
802 if (best_p
->size
- rounded_size
>= alignment
)
804 p
= ggc_alloc_temp_slot ();
806 p
->size
= best_p
->size
- rounded_size
;
807 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
808 p
->full_size
= best_p
->full_size
- rounded_size
;
809 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
810 p
->align
= best_p
->align
;
811 p
->type
= best_p
->type
;
812 insert_slot_to_list (p
, &avail_temp_slots
);
814 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
817 best_p
->size
= rounded_size
;
818 best_p
->full_size
= rounded_size
;
823 /* If we still didn't find one, make a new temporary. */
826 HOST_WIDE_INT frame_offset_old
= frame_offset
;
828 p
= ggc_alloc_temp_slot ();
830 /* We are passing an explicit alignment request to assign_stack_local.
831 One side effect of that is assign_stack_local will not round SIZE
832 to ensure the frame offset remains suitably aligned.
834 So for requests which depended on the rounding of SIZE, we go ahead
835 and round it now. We also make sure ALIGNMENT is at least
836 BIGGEST_ALIGNMENT. */
837 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
838 p
->slot
= assign_stack_local_1 (mode
,
848 /* The following slot size computation is necessary because we don't
849 know the actual size of the temporary slot until assign_stack_local
850 has performed all the frame alignment and size rounding for the
851 requested temporary. Note that extra space added for alignment
852 can be either above or below this stack slot depending on which
853 way the frame grows. We include the extra space if and only if it
854 is above this slot. */
855 if (FRAME_GROWS_DOWNWARD
)
856 p
->size
= frame_offset_old
- frame_offset
;
860 /* Now define the fields used by combine_temp_slots. */
861 if (FRAME_GROWS_DOWNWARD
)
863 p
->base_offset
= frame_offset
;
864 p
->full_size
= frame_offset_old
- frame_offset
;
868 p
->base_offset
= frame_offset_old
;
869 p
->full_size
= frame_offset
- frame_offset_old
;
878 p
->level
= temp_slot_level
;
879 n_temp_slots_in_use
++;
881 pp
= temp_slots_at_level (p
->level
);
882 insert_slot_to_list (p
, pp
);
883 insert_temp_slot_address (XEXP (p
->slot
, 0), p
);
885 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
886 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
887 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
889 /* If we know the alias set for the memory that will be used, use
890 it. If there's no TYPE, then we don't know anything about the
891 alias set for the memory. */
892 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
893 set_mem_align (slot
, align
);
895 /* If a type is specified, set the relevant flags. */
897 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
898 MEM_NOTRAP_P (slot
) = 1;
903 /* Allocate a temporary stack slot and record it for possible later
904 reuse. First two arguments are same as in preceding function. */
907 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
)
909 return assign_stack_temp_for_type (mode
, size
, NULL_TREE
);
912 /* Assign a temporary.
913 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
914 and so that should be used in error messages. In either case, we
915 allocate of the given type.
916 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
917 it is 0 if a register is OK.
918 DONT_PROMOTE is 1 if we should not promote values in register
922 assign_temp (tree type_or_decl
, int memory_required
,
923 int dont_promote ATTRIBUTE_UNUSED
)
926 enum machine_mode mode
;
931 if (DECL_P (type_or_decl
))
932 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
934 decl
= NULL
, type
= type_or_decl
;
936 mode
= TYPE_MODE (type
);
938 unsignedp
= TYPE_UNSIGNED (type
);
941 if (mode
== BLKmode
|| memory_required
)
943 HOST_WIDE_INT size
= int_size_in_bytes (type
);
946 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
947 problems with allocating the stack space. */
951 /* Unfortunately, we don't yet know how to allocate variable-sized
952 temporaries. However, sometimes we can find a fixed upper limit on
953 the size, so try that instead. */
955 size
= max_int_size_in_bytes (type
);
957 /* The size of the temporary may be too large to fit into an integer. */
958 /* ??? Not sure this should happen except for user silliness, so limit
959 this to things that aren't compiler-generated temporaries. The
960 rest of the time we'll die in assign_stack_temp_for_type. */
961 if (decl
&& size
== -1
962 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
964 error ("size of variable %q+D is too large", decl
);
968 tmp
= assign_stack_temp_for_type (mode
, size
, type
);
974 mode
= promote_mode (type
, mode
, &unsignedp
);
977 return gen_reg_rtx (mode
);
980 /* Combine temporary stack slots which are adjacent on the stack.
982 This allows for better use of already allocated stack space. This is only
983 done for BLKmode slots because we can be sure that we won't have alignment
984 problems in this case. */
987 combine_temp_slots (void)
989 struct temp_slot
*p
, *q
, *next
, *next_q
;
992 /* We can't combine slots, because the information about which slot
993 is in which alias set will be lost. */
994 if (flag_strict_aliasing
)
997 /* If there are a lot of temp slots, don't do anything unless
998 high levels of optimization. */
999 if (! flag_expensive_optimizations
)
1000 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
1001 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
1004 for (p
= avail_temp_slots
; p
; p
= next
)
1010 if (GET_MODE (p
->slot
) != BLKmode
)
1013 for (q
= p
->next
; q
; q
= next_q
)
1019 if (GET_MODE (q
->slot
) != BLKmode
)
1022 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
1024 /* Q comes after P; combine Q into P. */
1026 p
->full_size
+= q
->full_size
;
1029 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
1031 /* P comes after Q; combine P into Q. */
1033 q
->full_size
+= p
->full_size
;
1038 cut_slot_from_list (q
, &avail_temp_slots
);
1041 /* Either delete P or advance past it. */
1043 cut_slot_from_list (p
, &avail_temp_slots
);
1047 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1048 slot that previously was known by OLD_RTX. */
1051 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
1053 struct temp_slot
*p
;
1055 if (rtx_equal_p (old_rtx
, new_rtx
))
1058 p
= find_temp_slot_from_address (old_rtx
);
1060 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1061 NEW_RTX is a register, see if one operand of the PLUS is a
1062 temporary location. If so, NEW_RTX points into it. Otherwise,
1063 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1064 in common between them. If so, try a recursive call on those
1068 if (GET_CODE (old_rtx
) != PLUS
)
1071 if (REG_P (new_rtx
))
1073 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
1074 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
1077 else if (GET_CODE (new_rtx
) != PLUS
)
1080 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
1081 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
1082 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
1083 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
1084 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
1085 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
1086 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
1087 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
1092 /* Otherwise add an alias for the temp's address. */
1093 insert_temp_slot_address (new_rtx
, p
);
1096 /* If X could be a reference to a temporary slot, mark that slot as
1097 belonging to the to one level higher than the current level. If X
1098 matched one of our slots, just mark that one. Otherwise, we can't
1099 easily predict which it is, so upgrade all of them.
1101 This is called when an ({...}) construct occurs and a statement
1102 returns a value in memory. */
1105 preserve_temp_slots (rtx x
)
1107 struct temp_slot
*p
= 0, *next
;
1112 /* If X is a register that is being used as a pointer, see if we have
1113 a temporary slot we know it points to. */
1114 if (REG_P (x
) && REG_POINTER (x
))
1115 p
= find_temp_slot_from_address (x
);
1117 /* If X is not in memory or is at a constant address, it cannot be in
1118 a temporary slot. */
1119 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1122 /* First see if we can find a match. */
1124 p
= find_temp_slot_from_address (XEXP (x
, 0));
1128 if (p
->level
== temp_slot_level
)
1129 move_slot_to_level (p
, temp_slot_level
- 1);
1133 /* Otherwise, preserve all non-kept slots at this level. */
1134 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1137 move_slot_to_level (p
, temp_slot_level
- 1);
1141 /* Free all temporaries used so far. This is normally called at the
1142 end of generating code for a statement. */
1145 free_temp_slots (void)
1147 struct temp_slot
*p
, *next
;
1148 bool some_available
= false;
1150 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1153 make_slot_available (p
);
1154 some_available
= true;
1159 remove_unused_temp_slot_addresses ();
1160 combine_temp_slots ();
1164 /* Push deeper into the nesting level for stack temporaries. */
1167 push_temp_slots (void)
1172 /* Pop a temporary nesting level. All slots in use in the current level
1176 pop_temp_slots (void)
1182 /* Initialize temporary slots. */
1185 init_temp_slots (void)
1187 /* We have not allocated any temporaries yet. */
1188 avail_temp_slots
= 0;
1189 vec_alloc (used_temp_slots
, 0);
1190 temp_slot_level
= 0;
1191 n_temp_slots_in_use
= 0;
1193 /* Set up the table to map addresses to temp slots. */
1194 if (! temp_slot_address_table
)
1195 temp_slot_address_table
= htab_create_ggc (32,
1196 temp_slot_address_hash
,
1197 temp_slot_address_eq
,
1200 htab_empty (temp_slot_address_table
);
1203 /* Functions and data structures to keep track of the values hard regs
1204 had at the start of the function. */
1206 /* Private type used by get_hard_reg_initial_reg, get_hard_reg_initial_val,
1207 and has_hard_reg_initial_val.. */
1208 typedef struct GTY(()) initial_value_pair
{
1211 } initial_value_pair
;
1212 /* ??? This could be a VEC but there is currently no way to define an
1213 opaque VEC type. This could be worked around by defining struct
1214 initial_value_pair in function.h. */
1215 typedef struct GTY(()) initial_value_struct
{
1218 initial_value_pair
* GTY ((length ("%h.num_entries"))) entries
;
1219 } initial_value_struct
;
1221 /* If a pseudo represents an initial hard reg (or expression), return
1222 it, else return NULL_RTX. */
1225 get_hard_reg_initial_reg (rtx reg
)
1227 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1233 for (i
= 0; i
< ivs
->num_entries
; i
++)
1234 if (rtx_equal_p (ivs
->entries
[i
].pseudo
, reg
))
1235 return ivs
->entries
[i
].hard_reg
;
1240 /* Make sure that there's a pseudo register of mode MODE that stores the
1241 initial value of hard register REGNO. Return an rtx for such a pseudo. */
1244 get_hard_reg_initial_val (enum machine_mode mode
, unsigned int regno
)
1246 struct initial_value_struct
*ivs
;
1249 rv
= has_hard_reg_initial_val (mode
, regno
);
1253 ivs
= crtl
->hard_reg_initial_vals
;
1256 ivs
= ggc_alloc_initial_value_struct ();
1257 ivs
->num_entries
= 0;
1258 ivs
->max_entries
= 5;
1259 ivs
->entries
= ggc_alloc_vec_initial_value_pair (5);
1260 crtl
->hard_reg_initial_vals
= ivs
;
1263 if (ivs
->num_entries
>= ivs
->max_entries
)
1265 ivs
->max_entries
+= 5;
1266 ivs
->entries
= GGC_RESIZEVEC (initial_value_pair
, ivs
->entries
,
1270 ivs
->entries
[ivs
->num_entries
].hard_reg
= gen_rtx_REG (mode
, regno
);
1271 ivs
->entries
[ivs
->num_entries
].pseudo
= gen_reg_rtx (mode
);
1273 return ivs
->entries
[ivs
->num_entries
++].pseudo
;
1276 /* See if get_hard_reg_initial_val has been used to create a pseudo
1277 for the initial value of hard register REGNO in mode MODE. Return
1278 the associated pseudo if so, otherwise return NULL. */
1281 has_hard_reg_initial_val (enum machine_mode mode
, unsigned int regno
)
1283 struct initial_value_struct
*ivs
;
1286 ivs
= crtl
->hard_reg_initial_vals
;
1288 for (i
= 0; i
< ivs
->num_entries
; i
++)
1289 if (GET_MODE (ivs
->entries
[i
].hard_reg
) == mode
1290 && REGNO (ivs
->entries
[i
].hard_reg
) == regno
)
1291 return ivs
->entries
[i
].pseudo
;
1297 emit_initial_value_sets (void)
1299 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1307 for (i
= 0; i
< ivs
->num_entries
; i
++)
1308 emit_move_insn (ivs
->entries
[i
].pseudo
, ivs
->entries
[i
].hard_reg
);
1312 emit_insn_at_entry (seq
);
1316 /* Return the hardreg-pseudoreg initial values pair entry I and
1317 TRUE if I is a valid entry, or FALSE if I is not a valid entry. */
1319 initial_value_entry (int i
, rtx
*hreg
, rtx
*preg
)
1321 struct initial_value_struct
*ivs
= crtl
->hard_reg_initial_vals
;
1322 if (!ivs
|| i
>= ivs
->num_entries
)
1325 *hreg
= ivs
->entries
[i
].hard_reg
;
1326 *preg
= ivs
->entries
[i
].pseudo
;
1330 /* These routines are responsible for converting virtual register references
1331 to the actual hard register references once RTL generation is complete.
1333 The following four variables are used for communication between the
1334 routines. They contain the offsets of the virtual registers from their
1335 respective hard registers. */
1337 static int in_arg_offset
;
1338 static int var_offset
;
1339 static int dynamic_offset
;
1340 static int out_arg_offset
;
1341 static int cfa_offset
;
1343 /* In most machines, the stack pointer register is equivalent to the bottom
1346 #ifndef STACK_POINTER_OFFSET
1347 #define STACK_POINTER_OFFSET 0
1350 /* If not defined, pick an appropriate default for the offset of dynamically
1351 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1352 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1354 #ifndef STACK_DYNAMIC_OFFSET
1356 /* The bottom of the stack points to the actual arguments. If
1357 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1358 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1359 stack space for register parameters is not pushed by the caller, but
1360 rather part of the fixed stack areas and hence not included in
1361 `crtl->outgoing_args_size'. Nevertheless, we must allow
1362 for it when allocating stack dynamic objects. */
1364 #if defined(REG_PARM_STACK_SPACE)
1365 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1366 ((ACCUMULATE_OUTGOING_ARGS \
1367 ? (crtl->outgoing_args_size \
1368 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1369 : REG_PARM_STACK_SPACE (FNDECL))) \
1370 : 0) + (STACK_POINTER_OFFSET))
1372 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1373 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1374 + (STACK_POINTER_OFFSET))
1379 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1380 is a virtual register, return the equivalent hard register and set the
1381 offset indirectly through the pointer. Otherwise, return 0. */
1384 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1387 HOST_WIDE_INT offset
;
1389 if (x
== virtual_incoming_args_rtx
)
1391 if (stack_realign_drap
)
1393 /* Replace virtual_incoming_args_rtx with internal arg
1394 pointer if DRAP is used to realign stack. */
1395 new_rtx
= crtl
->args
.internal_arg_pointer
;
1399 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1401 else if (x
== virtual_stack_vars_rtx
)
1402 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1403 else if (x
== virtual_stack_dynamic_rtx
)
1404 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1405 else if (x
== virtual_outgoing_args_rtx
)
1406 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1407 else if (x
== virtual_cfa_rtx
)
1409 #ifdef FRAME_POINTER_CFA_OFFSET
1410 new_rtx
= frame_pointer_rtx
;
1412 new_rtx
= arg_pointer_rtx
;
1414 offset
= cfa_offset
;
1416 else if (x
== virtual_preferred_stack_boundary_rtx
)
1418 new_rtx
= GEN_INT (crtl
->preferred_stack_boundary
/ BITS_PER_UNIT
);
1428 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1429 Instantiate any virtual registers present inside of *LOC. The expression
1430 is simplified, as much as possible, but is not to be considered "valid"
1431 in any sense implied by the target. If any change is made, set CHANGED
1435 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1437 HOST_WIDE_INT offset
;
1438 bool *changed
= (bool *) data
;
1445 switch (GET_CODE (x
))
1448 new_rtx
= instantiate_new_reg (x
, &offset
);
1451 *loc
= plus_constant (GET_MODE (x
), new_rtx
, offset
);
1458 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1461 new_rtx
= plus_constant (GET_MODE (x
), new_rtx
, offset
);
1462 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1468 /* FIXME -- from old code */
1469 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1470 we can commute the PLUS and SUBREG because pointers into the
1471 frame are well-behaved. */
1481 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1482 matches the predicate for insn CODE operand OPERAND. */
1485 safe_insn_predicate (int code
, int operand
, rtx x
)
1487 return code
< 0 || insn_operand_matches ((enum insn_code
) code
, operand
, x
);
1490 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1491 registers present inside of insn. The result will be a valid insn. */
1494 instantiate_virtual_regs_in_insn (rtx insn
)
1496 HOST_WIDE_INT offset
;
1498 bool any_change
= false;
1499 rtx set
, new_rtx
, x
, seq
;
1501 /* There are some special cases to be handled first. */
1502 set
= single_set (insn
);
1505 /* We're allowed to assign to a virtual register. This is interpreted
1506 to mean that the underlying register gets assigned the inverse
1507 transformation. This is used, for example, in the handling of
1509 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1514 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1515 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1516 gen_int_mode (-offset
, GET_MODE (new_rtx
)));
1517 x
= force_operand (x
, new_rtx
);
1519 emit_move_insn (new_rtx
, x
);
1524 emit_insn_before (seq
, insn
);
1529 /* Handle a straight copy from a virtual register by generating a
1530 new add insn. The difference between this and falling through
1531 to the generic case is avoiding a new pseudo and eliminating a
1532 move insn in the initial rtl stream. */
1533 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1534 if (new_rtx
&& offset
!= 0
1535 && REG_P (SET_DEST (set
))
1536 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1540 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
, new_rtx
,
1541 gen_int_mode (offset
,
1542 GET_MODE (SET_DEST (set
))),
1543 SET_DEST (set
), 1, OPTAB_LIB_WIDEN
);
1544 if (x
!= SET_DEST (set
))
1545 emit_move_insn (SET_DEST (set
), x
);
1550 emit_insn_before (seq
, insn
);
1555 extract_insn (insn
);
1556 insn_code
= INSN_CODE (insn
);
1558 /* Handle a plus involving a virtual register by determining if the
1559 operands remain valid if they're modified in place. */
1560 if (GET_CODE (SET_SRC (set
)) == PLUS
1561 && recog_data
.n_operands
>= 3
1562 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1563 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1564 && CONST_INT_P (recog_data
.operand
[2])
1565 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1567 offset
+= INTVAL (recog_data
.operand
[2]);
1569 /* If the sum is zero, then replace with a plain move. */
1571 && REG_P (SET_DEST (set
))
1572 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1575 emit_move_insn (SET_DEST (set
), new_rtx
);
1579 emit_insn_before (seq
, insn
);
1584 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1586 /* Using validate_change and apply_change_group here leaves
1587 recog_data in an invalid state. Since we know exactly what
1588 we want to check, do those two by hand. */
1589 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1590 && safe_insn_predicate (insn_code
, 2, x
))
1592 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1593 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1596 /* Fall through into the regular operand fixup loop in
1597 order to take care of operands other than 1 and 2. */
1603 extract_insn (insn
);
1604 insn_code
= INSN_CODE (insn
);
1607 /* In the general case, we expect virtual registers to appear only in
1608 operands, and then only as either bare registers or inside memories. */
1609 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1611 x
= recog_data
.operand
[i
];
1612 switch (GET_CODE (x
))
1616 rtx addr
= XEXP (x
, 0);
1617 bool changed
= false;
1619 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1624 x
= replace_equiv_address (x
, addr
);
1625 /* It may happen that the address with the virtual reg
1626 was valid (e.g. based on the virtual stack reg, which might
1627 be acceptable to the predicates with all offsets), whereas
1628 the address now isn't anymore, for instance when the address
1629 is still offsetted, but the base reg isn't virtual-stack-reg
1630 anymore. Below we would do a force_reg on the whole operand,
1631 but this insn might actually only accept memory. Hence,
1632 before doing that last resort, try to reload the address into
1633 a register, so this operand stays a MEM. */
1634 if (!safe_insn_predicate (insn_code
, i
, x
))
1636 addr
= force_reg (GET_MODE (addr
), addr
);
1637 x
= replace_equiv_address (x
, addr
);
1642 emit_insn_before (seq
, insn
);
1647 new_rtx
= instantiate_new_reg (x
, &offset
);
1648 if (new_rtx
== NULL
)
1656 /* Careful, special mode predicates may have stuff in
1657 insn_data[insn_code].operand[i].mode that isn't useful
1658 to us for computing a new value. */
1659 /* ??? Recognize address_operand and/or "p" constraints
1660 to see if (plus new offset) is a valid before we put
1661 this through expand_simple_binop. */
1662 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1663 gen_int_mode (offset
, GET_MODE (x
)),
1664 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1667 emit_insn_before (seq
, insn
);
1672 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1673 if (new_rtx
== NULL
)
1678 new_rtx
= expand_simple_binop
1679 (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1680 gen_int_mode (offset
, GET_MODE (new_rtx
)),
1681 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1684 emit_insn_before (seq
, insn
);
1686 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1687 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1695 /* At this point, X contains the new value for the operand.
1696 Validate the new value vs the insn predicate. Note that
1697 asm insns will have insn_code -1 here. */
1698 if (!safe_insn_predicate (insn_code
, i
, x
))
1703 gcc_assert (REGNO (x
) <= LAST_VIRTUAL_REGISTER
);
1704 x
= copy_to_reg (x
);
1707 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1711 emit_insn_before (seq
, insn
);
1714 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1720 /* Propagate operand changes into the duplicates. */
1721 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1722 *recog_data
.dup_loc
[i
]
1723 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1725 /* Force re-recognition of the instruction for validation. */
1726 INSN_CODE (insn
) = -1;
1729 if (asm_noperands (PATTERN (insn
)) >= 0)
1731 if (!check_asm_operands (PATTERN (insn
)))
1733 error_for_asm (insn
, "impossible constraint in %<asm%>");
1734 /* For asm goto, instead of fixing up all the edges
1735 just clear the template and clear input operands
1736 (asm goto doesn't have any output operands). */
1739 rtx asm_op
= extract_asm_operands (PATTERN (insn
));
1740 ASM_OPERANDS_TEMPLATE (asm_op
) = ggc_strdup ("");
1741 ASM_OPERANDS_INPUT_VEC (asm_op
) = rtvec_alloc (0);
1742 ASM_OPERANDS_INPUT_CONSTRAINT_VEC (asm_op
) = rtvec_alloc (0);
1750 if (recog_memoized (insn
) < 0)
1751 fatal_insn_not_found (insn
);
1755 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1756 do any instantiation required. */
1759 instantiate_decl_rtl (rtx x
)
1766 /* If this is a CONCAT, recurse for the pieces. */
1767 if (GET_CODE (x
) == CONCAT
)
1769 instantiate_decl_rtl (XEXP (x
, 0));
1770 instantiate_decl_rtl (XEXP (x
, 1));
1774 /* If this is not a MEM, no need to do anything. Similarly if the
1775 address is a constant or a register that is not a virtual register. */
1780 if (CONSTANT_P (addr
)
1782 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1783 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1786 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1789 /* Helper for instantiate_decls called via walk_tree: Process all decls
1790 in the given DECL_VALUE_EXPR. */
1793 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1801 if (DECL_RTL_SET_P (t
))
1802 instantiate_decl_rtl (DECL_RTL (t
));
1803 if (TREE_CODE (t
) == PARM_DECL
&& DECL_NAMELESS (t
)
1804 && DECL_INCOMING_RTL (t
))
1805 instantiate_decl_rtl (DECL_INCOMING_RTL (t
));
1806 if ((TREE_CODE (t
) == VAR_DECL
1807 || TREE_CODE (t
) == RESULT_DECL
)
1808 && DECL_HAS_VALUE_EXPR_P (t
))
1810 tree v
= DECL_VALUE_EXPR (t
);
1811 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1818 /* Subroutine of instantiate_decls: Process all decls in the given
1819 BLOCK node and all its subblocks. */
1822 instantiate_decls_1 (tree let
)
1826 for (t
= BLOCK_VARS (let
); t
; t
= DECL_CHAIN (t
))
1828 if (DECL_RTL_SET_P (t
))
1829 instantiate_decl_rtl (DECL_RTL (t
));
1830 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1832 tree v
= DECL_VALUE_EXPR (t
);
1833 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1837 /* Process all subblocks. */
1838 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1839 instantiate_decls_1 (t
);
1842 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1843 all virtual registers in their DECL_RTL's. */
1846 instantiate_decls (tree fndecl
)
1851 /* Process all parameters of the function. */
1852 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= DECL_CHAIN (decl
))
1854 instantiate_decl_rtl (DECL_RTL (decl
));
1855 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1856 if (DECL_HAS_VALUE_EXPR_P (decl
))
1858 tree v
= DECL_VALUE_EXPR (decl
);
1859 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1863 if ((decl
= DECL_RESULT (fndecl
))
1864 && TREE_CODE (decl
) == RESULT_DECL
)
1866 if (DECL_RTL_SET_P (decl
))
1867 instantiate_decl_rtl (DECL_RTL (decl
));
1868 if (DECL_HAS_VALUE_EXPR_P (decl
))
1870 tree v
= DECL_VALUE_EXPR (decl
);
1871 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1875 /* Now process all variables defined in the function or its subblocks. */
1876 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1878 FOR_EACH_LOCAL_DECL (cfun
, ix
, decl
)
1879 if (DECL_RTL_SET_P (decl
))
1880 instantiate_decl_rtl (DECL_RTL (decl
));
1881 vec_free (cfun
->local_decls
);
1884 /* Pass through the INSNS of function FNDECL and convert virtual register
1885 references to hard register references. */
1888 instantiate_virtual_regs (void)
1892 /* Compute the offsets to use for this function. */
1893 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1894 var_offset
= STARTING_FRAME_OFFSET
;
1895 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1896 out_arg_offset
= STACK_POINTER_OFFSET
;
1897 #ifdef FRAME_POINTER_CFA_OFFSET
1898 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1900 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1903 /* Initialize recognition, indicating that volatile is OK. */
1906 /* Scan through all the insns, instantiating every virtual register still
1908 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1911 /* These patterns in the instruction stream can never be recognized.
1912 Fortunately, they shouldn't contain virtual registers either. */
1913 if (GET_CODE (PATTERN (insn
)) == USE
1914 || GET_CODE (PATTERN (insn
)) == CLOBBER
1915 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1917 else if (DEBUG_INSN_P (insn
))
1918 for_each_rtx (&INSN_VAR_LOCATION (insn
),
1919 instantiate_virtual_regs_in_rtx
, NULL
);
1921 instantiate_virtual_regs_in_insn (insn
);
1923 if (INSN_DELETED_P (insn
))
1926 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1928 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1930 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1931 instantiate_virtual_regs_in_rtx
, NULL
);
1934 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1935 instantiate_decls (current_function_decl
);
1937 targetm
.instantiate_decls ();
1939 /* Indicate that, from now on, assign_stack_local should use
1940 frame_pointer_rtx. */
1941 virtuals_instantiated
= 1;
1948 const pass_data pass_data_instantiate_virtual_regs
=
1950 RTL_PASS
, /* type */
1952 OPTGROUP_NONE
, /* optinfo_flags */
1953 true, /* has_execute */
1954 TV_NONE
, /* tv_id */
1955 0, /* properties_required */
1956 0, /* properties_provided */
1957 0, /* properties_destroyed */
1958 0, /* todo_flags_start */
1959 0, /* todo_flags_finish */
1962 class pass_instantiate_virtual_regs
: public rtl_opt_pass
1965 pass_instantiate_virtual_regs (gcc::context
*ctxt
)
1966 : rtl_opt_pass (pass_data_instantiate_virtual_regs
, ctxt
)
1969 /* opt_pass methods: */
1970 unsigned int execute () { return instantiate_virtual_regs (); }
1972 }; // class pass_instantiate_virtual_regs
1977 make_pass_instantiate_virtual_regs (gcc::context
*ctxt
)
1979 return new pass_instantiate_virtual_regs (ctxt
);
1983 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1984 This means a type for which function calls must pass an address to the
1985 function or get an address back from the function.
1986 EXP may be a type node or an expression (whose type is tested). */
1989 aggregate_value_p (const_tree exp
, const_tree fntype
)
1991 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1992 int i
, regno
, nregs
;
1996 switch (TREE_CODE (fntype
))
2000 tree fndecl
= get_callee_fndecl (fntype
);
2002 ? TREE_TYPE (fndecl
)
2003 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype
))));
2007 fntype
= TREE_TYPE (fntype
);
2012 case IDENTIFIER_NODE
:
2016 /* We don't expect other tree types here. */
2020 if (VOID_TYPE_P (type
))
2023 /* If a record should be passed the same as its first (and only) member
2024 don't pass it as an aggregate. */
2025 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2026 return aggregate_value_p (first_field (type
), fntype
);
2028 /* If the front end has decided that this needs to be passed by
2029 reference, do so. */
2030 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
2031 && DECL_BY_REFERENCE (exp
))
2034 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2035 if (fntype
&& TREE_ADDRESSABLE (fntype
))
2038 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2039 and thus can't be returned in registers. */
2040 if (TREE_ADDRESSABLE (type
))
2043 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
2046 if (targetm
.calls
.return_in_memory (type
, fntype
))
2049 /* Make sure we have suitable call-clobbered regs to return
2050 the value in; if not, we must return it in memory. */
2051 reg
= hard_function_value (type
, 0, fntype
, 0);
2053 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2058 regno
= REGNO (reg
);
2059 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
2060 for (i
= 0; i
< nregs
; i
++)
2061 if (! call_used_regs
[regno
+ i
])
2067 /* Return true if we should assign DECL a pseudo register; false if it
2068 should live on the local stack. */
2071 use_register_for_decl (const_tree decl
)
2073 if (!targetm
.calls
.allocate_stack_slots_for_args ())
2076 /* Honor volatile. */
2077 if (TREE_SIDE_EFFECTS (decl
))
2080 /* Honor addressability. */
2081 if (TREE_ADDRESSABLE (decl
))
2084 /* Only register-like things go in registers. */
2085 if (DECL_MODE (decl
) == BLKmode
)
2088 /* If -ffloat-store specified, don't put explicit float variables
2090 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2091 propagates values across these stores, and it probably shouldn't. */
2092 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
2095 /* If we're not interested in tracking debugging information for
2096 this decl, then we can certainly put it in a register. */
2097 if (DECL_IGNORED_P (decl
))
2103 if (!DECL_REGISTER (decl
))
2106 switch (TREE_CODE (TREE_TYPE (decl
)))
2110 case QUAL_UNION_TYPE
:
2111 /* When not optimizing, disregard register keyword for variables with
2112 types containing methods, otherwise the methods won't be callable
2113 from the debugger. */
2114 if (TYPE_METHODS (TREE_TYPE (decl
)))
2124 /* Return true if TYPE should be passed by invisible reference. */
2127 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
2128 tree type
, bool named_arg
)
2132 /* If this type contains non-trivial constructors, then it is
2133 forbidden for the middle-end to create any new copies. */
2134 if (TREE_ADDRESSABLE (type
))
2137 /* GCC post 3.4 passes *all* variable sized types by reference. */
2138 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
2141 /* If a record type should be passed the same as its first (and only)
2142 member, use the type and mode of that member. */
2143 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2145 type
= TREE_TYPE (first_field (type
));
2146 mode
= TYPE_MODE (type
);
2150 return targetm
.calls
.pass_by_reference (pack_cumulative_args (ca
), mode
,
2154 /* Return true if TYPE, which is passed by reference, should be callee
2155 copied instead of caller copied. */
2158 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
2159 tree type
, bool named_arg
)
2161 if (type
&& TREE_ADDRESSABLE (type
))
2163 return targetm
.calls
.callee_copies (pack_cumulative_args (ca
), mode
, type
,
2167 /* Structures to communicate between the subroutines of assign_parms.
2168 The first holds data persistent across all parameters, the second
2169 is cleared out for each parameter. */
2171 struct assign_parm_data_all
2173 /* When INIT_CUMULATIVE_ARGS gets revamped, allocating CUMULATIVE_ARGS
2174 should become a job of the target or otherwise encapsulated. */
2175 CUMULATIVE_ARGS args_so_far_v
;
2176 cumulative_args_t args_so_far
;
2177 struct args_size stack_args_size
;
2178 tree function_result_decl
;
2180 rtx first_conversion_insn
;
2181 rtx last_conversion_insn
;
2182 HOST_WIDE_INT pretend_args_size
;
2183 HOST_WIDE_INT extra_pretend_bytes
;
2184 int reg_parm_stack_space
;
2187 struct assign_parm_data_one
2193 enum machine_mode nominal_mode
;
2194 enum machine_mode passed_mode
;
2195 enum machine_mode promoted_mode
;
2196 struct locate_and_pad_arg_data locate
;
2198 BOOL_BITFIELD named_arg
: 1;
2199 BOOL_BITFIELD passed_pointer
: 1;
2200 BOOL_BITFIELD on_stack
: 1;
2201 BOOL_BITFIELD loaded_in_reg
: 1;
2204 /* A subroutine of assign_parms. Initialize ALL. */
2207 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2209 tree fntype ATTRIBUTE_UNUSED
;
2211 memset (all
, 0, sizeof (*all
));
2213 fntype
= TREE_TYPE (current_function_decl
);
2215 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2216 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
);
2218 INIT_CUMULATIVE_ARGS (all
->args_so_far_v
, fntype
, NULL_RTX
,
2219 current_function_decl
, -1);
2221 all
->args_so_far
= pack_cumulative_args (&all
->args_so_far_v
);
2223 #ifdef REG_PARM_STACK_SPACE
2224 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
2228 /* If ARGS contains entries with complex types, split the entry into two
2229 entries of the component type. Return a new list of substitutions are
2230 needed, else the old list. */
2233 split_complex_args (vec
<tree
> *args
)
2238 FOR_EACH_VEC_ELT (*args
, i
, p
)
2240 tree type
= TREE_TYPE (p
);
2241 if (TREE_CODE (type
) == COMPLEX_TYPE
2242 && targetm
.calls
.split_complex_arg (type
))
2245 tree subtype
= TREE_TYPE (type
);
2246 bool addressable
= TREE_ADDRESSABLE (p
);
2248 /* Rewrite the PARM_DECL's type with its component. */
2250 TREE_TYPE (p
) = subtype
;
2251 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2252 DECL_MODE (p
) = VOIDmode
;
2253 DECL_SIZE (p
) = NULL
;
2254 DECL_SIZE_UNIT (p
) = NULL
;
2255 /* If this arg must go in memory, put it in a pseudo here.
2256 We can't allow it to go in memory as per normal parms,
2257 because the usual place might not have the imag part
2258 adjacent to the real part. */
2259 DECL_ARTIFICIAL (p
) = addressable
;
2260 DECL_IGNORED_P (p
) = addressable
;
2261 TREE_ADDRESSABLE (p
) = 0;
2265 /* Build a second synthetic decl. */
2266 decl
= build_decl (EXPR_LOCATION (p
),
2267 PARM_DECL
, NULL_TREE
, subtype
);
2268 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2269 DECL_ARTIFICIAL (decl
) = addressable
;
2270 DECL_IGNORED_P (decl
) = addressable
;
2271 layout_decl (decl
, 0);
2272 args
->safe_insert (++i
, decl
);
2277 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2278 the hidden struct return argument, and (abi willing) complex args.
2279 Return the new parameter list. */
2282 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2284 tree fndecl
= current_function_decl
;
2285 tree fntype
= TREE_TYPE (fndecl
);
2286 vec
<tree
> fnargs
= vNULL
;
2289 for (arg
= DECL_ARGUMENTS (fndecl
); arg
; arg
= DECL_CHAIN (arg
))
2290 fnargs
.safe_push (arg
);
2292 all
->orig_fnargs
= DECL_ARGUMENTS (fndecl
);
2294 /* If struct value address is treated as the first argument, make it so. */
2295 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2296 && ! cfun
->returns_pcc_struct
2297 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2299 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2302 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2303 PARM_DECL
, get_identifier (".result_ptr"), type
);
2304 DECL_ARG_TYPE (decl
) = type
;
2305 DECL_ARTIFICIAL (decl
) = 1;
2306 DECL_NAMELESS (decl
) = 1;
2307 TREE_CONSTANT (decl
) = 1;
2309 DECL_CHAIN (decl
) = all
->orig_fnargs
;
2310 all
->orig_fnargs
= decl
;
2311 fnargs
.safe_insert (0, decl
);
2313 all
->function_result_decl
= decl
;
2316 /* If the target wants to split complex arguments into scalars, do so. */
2317 if (targetm
.calls
.split_complex_arg
)
2318 split_complex_args (&fnargs
);
2323 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2324 data for the parameter. Incorporate ABI specifics such as pass-by-
2325 reference and type promotion. */
2328 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2329 struct assign_parm_data_one
*data
)
2331 tree nominal_type
, passed_type
;
2332 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2335 memset (data
, 0, sizeof (*data
));
2337 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2339 data
->named_arg
= 1; /* No variadic parms. */
2340 else if (DECL_CHAIN (parm
))
2341 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2342 else if (targetm
.calls
.strict_argument_naming (all
->args_so_far
))
2343 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2345 data
->named_arg
= 0; /* Treat as variadic. */
2347 nominal_type
= TREE_TYPE (parm
);
2348 passed_type
= DECL_ARG_TYPE (parm
);
2350 /* Look out for errors propagating this far. Also, if the parameter's
2351 type is void then its value doesn't matter. */
2352 if (TREE_TYPE (parm
) == error_mark_node
2353 /* This can happen after weird syntax errors
2354 or if an enum type is defined among the parms. */
2355 || TREE_CODE (parm
) != PARM_DECL
2356 || passed_type
== NULL
2357 || VOID_TYPE_P (nominal_type
))
2359 nominal_type
= passed_type
= void_type_node
;
2360 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2364 /* Find mode of arg as it is passed, and mode of arg as it should be
2365 during execution of this function. */
2366 passed_mode
= TYPE_MODE (passed_type
);
2367 nominal_mode
= TYPE_MODE (nominal_type
);
2369 /* If the parm is to be passed as a transparent union or record, use the
2370 type of the first field for the tests below. We have already verified
2371 that the modes are the same. */
2372 if ((TREE_CODE (passed_type
) == UNION_TYPE
2373 || TREE_CODE (passed_type
) == RECORD_TYPE
)
2374 && TYPE_TRANSPARENT_AGGR (passed_type
))
2375 passed_type
= TREE_TYPE (first_field (passed_type
));
2377 /* See if this arg was passed by invisible reference. */
2378 if (pass_by_reference (&all
->args_so_far_v
, passed_mode
,
2379 passed_type
, data
->named_arg
))
2381 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2382 data
->passed_pointer
= true;
2383 passed_mode
= nominal_mode
= TYPE_MODE (nominal_type
);
2386 /* Find mode as it is passed by the ABI. */
2387 unsignedp
= TYPE_UNSIGNED (passed_type
);
2388 promoted_mode
= promote_function_mode (passed_type
, passed_mode
, &unsignedp
,
2389 TREE_TYPE (current_function_decl
), 0);
2392 data
->nominal_type
= nominal_type
;
2393 data
->passed_type
= passed_type
;
2394 data
->nominal_mode
= nominal_mode
;
2395 data
->passed_mode
= passed_mode
;
2396 data
->promoted_mode
= promoted_mode
;
2399 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2402 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2403 struct assign_parm_data_one
*data
, bool no_rtl
)
2405 int varargs_pretend_bytes
= 0;
2407 targetm
.calls
.setup_incoming_varargs (all
->args_so_far
,
2408 data
->promoted_mode
,
2410 &varargs_pretend_bytes
, no_rtl
);
2412 /* If the back-end has requested extra stack space, record how much is
2413 needed. Do not change pretend_args_size otherwise since it may be
2414 nonzero from an earlier partial argument. */
2415 if (varargs_pretend_bytes
> 0)
2416 all
->pretend_args_size
= varargs_pretend_bytes
;
2419 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2420 the incoming location of the current parameter. */
2423 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2424 struct assign_parm_data_one
*data
)
2426 HOST_WIDE_INT pretend_bytes
= 0;
2430 if (data
->promoted_mode
== VOIDmode
)
2432 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2436 entry_parm
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2437 data
->promoted_mode
,
2441 if (entry_parm
== 0)
2442 data
->promoted_mode
= data
->passed_mode
;
2444 /* Determine parm's home in the stack, in case it arrives in the stack
2445 or we should pretend it did. Compute the stack position and rtx where
2446 the argument arrives and its size.
2448 There is one complexity here: If this was a parameter that would
2449 have been passed in registers, but wasn't only because it is
2450 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2451 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2452 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2453 as it was the previous time. */
2454 in_regs
= entry_parm
!= 0;
2455 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2458 if (!in_regs
&& !data
->named_arg
)
2460 if (targetm
.calls
.pretend_outgoing_varargs_named (all
->args_so_far
))
2463 tem
= targetm
.calls
.function_incoming_arg (all
->args_so_far
,
2464 data
->promoted_mode
,
2465 data
->passed_type
, true);
2466 in_regs
= tem
!= NULL
;
2470 /* If this parameter was passed both in registers and in the stack, use
2471 the copy on the stack. */
2472 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2480 partial
= targetm
.calls
.arg_partial_bytes (all
->args_so_far
,
2481 data
->promoted_mode
,
2484 data
->partial
= partial
;
2486 /* The caller might already have allocated stack space for the
2487 register parameters. */
2488 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2490 /* Part of this argument is passed in registers and part
2491 is passed on the stack. Ask the prologue code to extend
2492 the stack part so that we can recreate the full value.
2494 PRETEND_BYTES is the size of the registers we need to store.
2495 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2496 stack space that the prologue should allocate.
2498 Internally, gcc assumes that the argument pointer is aligned
2499 to STACK_BOUNDARY bits. This is used both for alignment
2500 optimizations (see init_emit) and to locate arguments that are
2501 aligned to more than PARM_BOUNDARY bits. We must preserve this
2502 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2503 a stack boundary. */
2505 /* We assume at most one partial arg, and it must be the first
2506 argument on the stack. */
2507 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2509 pretend_bytes
= partial
;
2510 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2512 /* We want to align relative to the actual stack pointer, so
2513 don't include this in the stack size until later. */
2514 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2518 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2519 all
->reg_parm_stack_space
,
2520 entry_parm
? data
->partial
: 0, current_function_decl
,
2521 &all
->stack_args_size
, &data
->locate
);
2523 /* Update parm_stack_boundary if this parameter is passed in the
2525 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2526 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2528 /* Adjust offsets to include the pretend args. */
2529 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2530 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2531 data
->locate
.offset
.constant
+= pretend_bytes
;
2533 data
->entry_parm
= entry_parm
;
2536 /* A subroutine of assign_parms. If there is actually space on the stack
2537 for this parm, count it in stack_args_size and return true. */
2540 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2541 struct assign_parm_data_one
*data
)
2543 /* Trivially true if we've no incoming register. */
2544 if (data
->entry_parm
== NULL
)
2546 /* Also true if we're partially in registers and partially not,
2547 since we've arranged to drop the entire argument on the stack. */
2548 else if (data
->partial
!= 0)
2550 /* Also true if the target says that it's passed in both registers
2551 and on the stack. */
2552 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2553 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2555 /* Also true if the target says that there's stack allocated for
2556 all register parameters. */
2557 else if (all
->reg_parm_stack_space
> 0)
2559 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2563 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2564 if (data
->locate
.size
.var
)
2565 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2570 /* A subroutine of assign_parms. Given that this parameter is allocated
2571 stack space by the ABI, find it. */
2574 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2576 rtx offset_rtx
, stack_parm
;
2577 unsigned int align
, boundary
;
2579 /* If we're passing this arg using a reg, make its stack home the
2580 aligned stack slot. */
2581 if (data
->entry_parm
)
2582 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2584 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2586 stack_parm
= crtl
->args
.internal_arg_pointer
;
2587 if (offset_rtx
!= const0_rtx
)
2588 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2589 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2591 if (!data
->passed_pointer
)
2593 set_mem_attributes (stack_parm
, parm
, 1);
2594 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2595 while promoted mode's size is needed. */
2596 if (data
->promoted_mode
!= BLKmode
2597 && data
->promoted_mode
!= DECL_MODE (parm
))
2599 set_mem_size (stack_parm
, GET_MODE_SIZE (data
->promoted_mode
));
2600 if (MEM_EXPR (stack_parm
) && MEM_OFFSET_KNOWN_P (stack_parm
))
2602 int offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2603 data
->promoted_mode
);
2605 set_mem_offset (stack_parm
, MEM_OFFSET (stack_parm
) - offset
);
2610 boundary
= data
->locate
.boundary
;
2611 align
= BITS_PER_UNIT
;
2613 /* If we're padding upward, we know that the alignment of the slot
2614 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2615 intentionally forcing upward padding. Otherwise we have to come
2616 up with a guess at the alignment based on OFFSET_RTX. */
2617 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2619 else if (CONST_INT_P (offset_rtx
))
2621 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2622 align
= align
& -align
;
2624 set_mem_align (stack_parm
, align
);
2626 if (data
->entry_parm
)
2627 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2629 data
->stack_parm
= stack_parm
;
2632 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2633 always valid and contiguous. */
2636 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2638 rtx entry_parm
= data
->entry_parm
;
2639 rtx stack_parm
= data
->stack_parm
;
2641 /* If this parm was passed part in regs and part in memory, pretend it
2642 arrived entirely in memory by pushing the register-part onto the stack.
2643 In the special case of a DImode or DFmode that is split, we could put
2644 it together in a pseudoreg directly, but for now that's not worth
2646 if (data
->partial
!= 0)
2648 /* Handle calls that pass values in multiple non-contiguous
2649 locations. The Irix 6 ABI has examples of this. */
2650 if (GET_CODE (entry_parm
) == PARALLEL
)
2651 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2653 int_size_in_bytes (data
->passed_type
));
2656 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2657 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2658 data
->partial
/ UNITS_PER_WORD
);
2661 entry_parm
= stack_parm
;
2664 /* If we didn't decide this parm came in a register, by default it came
2666 else if (entry_parm
== NULL
)
2667 entry_parm
= stack_parm
;
2669 /* When an argument is passed in multiple locations, we can't make use
2670 of this information, but we can save some copying if the whole argument
2671 is passed in a single register. */
2672 else if (GET_CODE (entry_parm
) == PARALLEL
2673 && data
->nominal_mode
!= BLKmode
2674 && data
->passed_mode
!= BLKmode
)
2676 size_t i
, len
= XVECLEN (entry_parm
, 0);
2678 for (i
= 0; i
< len
; i
++)
2679 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2680 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2681 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2682 == data
->passed_mode
)
2683 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2685 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2690 data
->entry_parm
= entry_parm
;
2693 /* A subroutine of assign_parms. Reconstitute any values which were
2694 passed in multiple registers and would fit in a single register. */
2697 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2699 rtx entry_parm
= data
->entry_parm
;
2701 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2702 This can be done with register operations rather than on the
2703 stack, even if we will store the reconstituted parameter on the
2705 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2707 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2708 emit_group_store (parmreg
, entry_parm
, data
->passed_type
,
2709 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2710 entry_parm
= parmreg
;
2713 data
->entry_parm
= entry_parm
;
2716 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2717 always valid and properly aligned. */
2720 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2722 rtx stack_parm
= data
->stack_parm
;
2724 /* If we can't trust the parm stack slot to be aligned enough for its
2725 ultimate type, don't use that slot after entry. We'll make another
2726 stack slot, if we need one. */
2728 && ((STRICT_ALIGNMENT
2729 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2730 || (data
->nominal_type
2731 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2732 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2735 /* If parm was passed in memory, and we need to convert it on entry,
2736 don't store it back in that same slot. */
2737 else if (data
->entry_parm
== stack_parm
2738 && data
->nominal_mode
!= BLKmode
2739 && data
->nominal_mode
!= data
->passed_mode
)
2742 /* If stack protection is in effect for this function, don't leave any
2743 pointers in their passed stack slots. */
2744 else if (crtl
->stack_protect_guard
2745 && (flag_stack_protect
== 2
2746 || data
->passed_pointer
2747 || POINTER_TYPE_P (data
->nominal_type
)))
2750 data
->stack_parm
= stack_parm
;
2753 /* A subroutine of assign_parms. Return true if the current parameter
2754 should be stored as a BLKmode in the current frame. */
2757 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2759 if (data
->nominal_mode
== BLKmode
)
2761 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2764 #ifdef BLOCK_REG_PADDING
2765 /* Only assign_parm_setup_block knows how to deal with register arguments
2766 that are padded at the least significant end. */
2767 if (REG_P (data
->entry_parm
)
2768 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2769 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2770 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2777 /* A subroutine of assign_parms. Arrange for the parameter to be
2778 present and valid in DATA->STACK_RTL. */
2781 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2782 tree parm
, struct assign_parm_data_one
*data
)
2784 rtx entry_parm
= data
->entry_parm
;
2785 rtx stack_parm
= data
->stack_parm
;
2787 HOST_WIDE_INT size_stored
;
2789 if (GET_CODE (entry_parm
) == PARALLEL
)
2790 entry_parm
= emit_group_move_into_temps (entry_parm
);
2792 size
= int_size_in_bytes (data
->passed_type
);
2793 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2794 if (stack_parm
== 0)
2796 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2797 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2799 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2800 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2801 set_mem_attributes (stack_parm
, parm
, 1);
2804 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2805 calls that pass values in multiple non-contiguous locations. */
2806 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2810 /* Note that we will be storing an integral number of words.
2811 So we have to be careful to ensure that we allocate an
2812 integral number of words. We do this above when we call
2813 assign_stack_local if space was not allocated in the argument
2814 list. If it was, this will not work if PARM_BOUNDARY is not
2815 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2816 if it becomes a problem. Exception is when BLKmode arrives
2817 with arguments not conforming to word_mode. */
2819 if (data
->stack_parm
== 0)
2821 else if (GET_CODE (entry_parm
) == PARALLEL
)
2824 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2826 mem
= validize_mem (stack_parm
);
2828 /* Handle values in multiple non-contiguous locations. */
2829 if (GET_CODE (entry_parm
) == PARALLEL
)
2831 push_to_sequence2 (all
->first_conversion_insn
,
2832 all
->last_conversion_insn
);
2833 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2834 all
->first_conversion_insn
= get_insns ();
2835 all
->last_conversion_insn
= get_last_insn ();
2842 /* If SIZE is that of a mode no bigger than a word, just use
2843 that mode's store operation. */
2844 else if (size
<= UNITS_PER_WORD
)
2846 enum machine_mode mode
2847 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2850 #ifdef BLOCK_REG_PADDING
2851 && (size
== UNITS_PER_WORD
2852 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2853 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2859 /* We are really truncating a word_mode value containing
2860 SIZE bytes into a value of mode MODE. If such an
2861 operation requires no actual instructions, we can refer
2862 to the value directly in mode MODE, otherwise we must
2863 start with the register in word_mode and explicitly
2865 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2866 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2869 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2870 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2872 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2875 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2876 machine must be aligned to the left before storing
2877 to memory. Note that the previous test doesn't
2878 handle all cases (e.g. SIZE == 3). */
2879 else if (size
!= UNITS_PER_WORD
2880 #ifdef BLOCK_REG_PADDING
2881 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2889 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2890 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2892 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, by
, NULL_RTX
, 1);
2893 tem
= change_address (mem
, word_mode
, 0);
2894 emit_move_insn (tem
, x
);
2897 move_block_from_reg (REGNO (entry_parm
), mem
,
2898 size_stored
/ UNITS_PER_WORD
);
2901 move_block_from_reg (REGNO (entry_parm
), mem
,
2902 size_stored
/ UNITS_PER_WORD
);
2904 else if (data
->stack_parm
== 0)
2906 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2907 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2909 all
->first_conversion_insn
= get_insns ();
2910 all
->last_conversion_insn
= get_last_insn ();
2914 data
->stack_parm
= stack_parm
;
2915 SET_DECL_RTL (parm
, stack_parm
);
2918 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2919 parameter. Get it there. Perform all ABI specified conversions. */
2922 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2923 struct assign_parm_data_one
*data
)
2925 rtx parmreg
, validated_mem
;
2926 rtx equiv_stack_parm
;
2927 enum machine_mode promoted_nominal_mode
;
2928 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2929 bool did_conversion
= false;
2930 bool need_conversion
, moved
;
2932 /* Store the parm in a pseudoregister during the function, but we may
2933 need to do it in a wider mode. Using 2 here makes the result
2934 consistent with promote_decl_mode and thus expand_expr_real_1. */
2935 promoted_nominal_mode
2936 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
2937 TREE_TYPE (current_function_decl
), 2);
2939 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2941 if (!DECL_ARTIFICIAL (parm
))
2942 mark_user_reg (parmreg
);
2944 /* If this was an item that we received a pointer to,
2945 set DECL_RTL appropriately. */
2946 if (data
->passed_pointer
)
2948 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2949 set_mem_attributes (x
, parm
, 1);
2950 SET_DECL_RTL (parm
, x
);
2953 SET_DECL_RTL (parm
, parmreg
);
2955 assign_parm_remove_parallels (data
);
2957 /* Copy the value into the register, thus bridging between
2958 assign_parm_find_data_types and expand_expr_real_1. */
2960 equiv_stack_parm
= data
->stack_parm
;
2961 validated_mem
= validize_mem (data
->entry_parm
);
2963 need_conversion
= (data
->nominal_mode
!= data
->passed_mode
2964 || promoted_nominal_mode
!= data
->promoted_mode
);
2968 && GET_MODE_CLASS (data
->nominal_mode
) == MODE_INT
2969 && data
->nominal_mode
== data
->passed_mode
2970 && data
->nominal_mode
== GET_MODE (data
->entry_parm
))
2972 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2973 mode, by the caller. We now have to convert it to
2974 NOMINAL_MODE, if different. However, PARMREG may be in
2975 a different mode than NOMINAL_MODE if it is being stored
2978 If ENTRY_PARM is a hard register, it might be in a register
2979 not valid for operating in its mode (e.g., an odd-numbered
2980 register for a DFmode). In that case, moves are the only
2981 thing valid, so we can't do a convert from there. This
2982 occurs when the calling sequence allow such misaligned
2985 In addition, the conversion may involve a call, which could
2986 clobber parameters which haven't been copied to pseudo
2989 First, we try to emit an insn which performs the necessary
2990 conversion. We verify that this insn does not clobber any
2993 enum insn_code icode
;
2996 icode
= can_extend_p (promoted_nominal_mode
, data
->passed_mode
,
3000 op1
= validated_mem
;
3001 if (icode
!= CODE_FOR_nothing
3002 && insn_operand_matches (icode
, 0, op0
)
3003 && insn_operand_matches (icode
, 1, op1
))
3005 enum rtx_code code
= unsignedp
? ZERO_EXTEND
: SIGN_EXTEND
;
3006 rtx insn
, insns
, t
= op1
;
3007 HARD_REG_SET hardregs
;
3010 /* If op1 is a hard register that is likely spilled, first
3011 force it into a pseudo, otherwise combiner might extend
3012 its lifetime too much. */
3013 if (GET_CODE (t
) == SUBREG
)
3016 && HARD_REGISTER_P (t
)
3017 && ! TEST_HARD_REG_BIT (fixed_reg_set
, REGNO (t
))
3018 && targetm
.class_likely_spilled_p (REGNO_REG_CLASS (REGNO (t
))))
3020 t
= gen_reg_rtx (GET_MODE (op1
));
3021 emit_move_insn (t
, op1
);
3025 insn
= gen_extend_insn (op0
, t
, promoted_nominal_mode
,
3026 data
->passed_mode
, unsignedp
);
3028 insns
= get_insns ();
3031 CLEAR_HARD_REG_SET (hardregs
);
3032 for (insn
= insns
; insn
&& moved
; insn
= NEXT_INSN (insn
))
3035 note_stores (PATTERN (insn
), record_hard_reg_sets
,
3037 if (!hard_reg_set_empty_p (hardregs
))
3046 if (equiv_stack_parm
!= NULL_RTX
)
3047 equiv_stack_parm
= gen_rtx_fmt_e (code
, GET_MODE (parmreg
),
3054 /* Nothing to do. */
3056 else if (need_conversion
)
3058 /* We did not have an insn to convert directly, or the sequence
3059 generated appeared unsafe. We must first copy the parm to a
3060 pseudo reg, and save the conversion until after all
3061 parameters have been moved. */
3064 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3066 emit_move_insn (tempreg
, validated_mem
);
3068 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3069 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
3071 if (GET_CODE (tempreg
) == SUBREG
3072 && GET_MODE (tempreg
) == data
->nominal_mode
3073 && REG_P (SUBREG_REG (tempreg
))
3074 && data
->nominal_mode
== data
->passed_mode
3075 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
3076 && GET_MODE_SIZE (GET_MODE (tempreg
))
3077 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
3079 /* The argument is already sign/zero extended, so note it
3081 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
3082 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
3085 /* TREE_USED gets set erroneously during expand_assignment. */
3086 save_tree_used
= TREE_USED (parm
);
3087 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
3088 TREE_USED (parm
) = save_tree_used
;
3089 all
->first_conversion_insn
= get_insns ();
3090 all
->last_conversion_insn
= get_last_insn ();
3093 did_conversion
= true;
3096 emit_move_insn (parmreg
, validated_mem
);
3098 /* If we were passed a pointer but the actual value can safely live
3099 in a register, retrieve it and use it directly. */
3100 if (data
->passed_pointer
&& TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
)
3102 /* We can't use nominal_mode, because it will have been set to
3103 Pmode above. We must use the actual mode of the parm. */
3104 if (use_register_for_decl (parm
))
3106 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
3107 mark_user_reg (parmreg
);
3111 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3112 TYPE_MODE (TREE_TYPE (parm
)),
3113 TYPE_ALIGN (TREE_TYPE (parm
)));
3115 = assign_stack_local (TYPE_MODE (TREE_TYPE (parm
)),
3116 GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (parm
))),
3118 set_mem_attributes (parmreg
, parm
, 1);
3121 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
3123 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
3124 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3126 push_to_sequence2 (all
->first_conversion_insn
,
3127 all
->last_conversion_insn
);
3128 emit_move_insn (tempreg
, DECL_RTL (parm
));
3129 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
3130 emit_move_insn (parmreg
, tempreg
);
3131 all
->first_conversion_insn
= get_insns ();
3132 all
->last_conversion_insn
= get_last_insn ();
3135 did_conversion
= true;
3138 emit_move_insn (parmreg
, DECL_RTL (parm
));
3140 SET_DECL_RTL (parm
, parmreg
);
3142 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3144 data
->stack_parm
= NULL
;
3147 /* Mark the register as eliminable if we did no conversion and it was
3148 copied from memory at a fixed offset, and the arg pointer was not
3149 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3150 offset formed an invalid address, such memory-equivalences as we
3151 make here would screw up life analysis for it. */
3152 if (data
->nominal_mode
== data
->passed_mode
3154 && data
->stack_parm
!= 0
3155 && MEM_P (data
->stack_parm
)
3156 && data
->locate
.offset
.var
== 0
3157 && reg_mentioned_p (virtual_incoming_args_rtx
,
3158 XEXP (data
->stack_parm
, 0)))
3160 rtx linsn
= get_last_insn ();
3163 /* Mark complex types separately. */
3164 if (GET_CODE (parmreg
) == CONCAT
)
3166 enum machine_mode submode
3167 = GET_MODE_INNER (GET_MODE (parmreg
));
3168 int regnor
= REGNO (XEXP (parmreg
, 0));
3169 int regnoi
= REGNO (XEXP (parmreg
, 1));
3170 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
3171 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
3172 GET_MODE_SIZE (submode
));
3174 /* Scan backwards for the set of the real and
3176 for (sinsn
= linsn
; sinsn
!= 0;
3177 sinsn
= prev_nonnote_insn (sinsn
))
3179 set
= single_set (sinsn
);
3183 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
3184 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
3185 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
3186 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
3190 set_dst_reg_note (linsn
, REG_EQUIV
, equiv_stack_parm
, parmreg
);
3193 /* For pointer data type, suggest pointer register. */
3194 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
3195 mark_reg_pointer (parmreg
,
3196 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
3199 /* A subroutine of assign_parms. Allocate stack space to hold the current
3200 parameter. Get it there. Perform all ABI specified conversions. */
3203 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
3204 struct assign_parm_data_one
*data
)
3206 /* Value must be stored in the stack slot STACK_PARM during function
3208 bool to_conversion
= false;
3210 assign_parm_remove_parallels (data
);
3212 if (data
->promoted_mode
!= data
->nominal_mode
)
3214 /* Conversion is required. */
3215 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3217 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
3219 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3220 to_conversion
= true;
3222 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
3223 TYPE_UNSIGNED (TREE_TYPE (parm
)));
3225 if (data
->stack_parm
)
3227 int offset
= subreg_lowpart_offset (data
->nominal_mode
,
3228 GET_MODE (data
->stack_parm
));
3229 /* ??? This may need a big-endian conversion on sparc64. */
3231 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
3232 if (offset
&& MEM_OFFSET_KNOWN_P (data
->stack_parm
))
3233 set_mem_offset (data
->stack_parm
,
3234 MEM_OFFSET (data
->stack_parm
) + offset
);
3238 if (data
->entry_parm
!= data
->stack_parm
)
3242 if (data
->stack_parm
== 0)
3244 int align
= STACK_SLOT_ALIGNMENT (data
->passed_type
,
3245 GET_MODE (data
->entry_parm
),
3246 TYPE_ALIGN (data
->passed_type
));
3248 = assign_stack_local (GET_MODE (data
->entry_parm
),
3249 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3251 set_mem_attributes (data
->stack_parm
, parm
, 1);
3254 dest
= validize_mem (data
->stack_parm
);
3255 src
= validize_mem (data
->entry_parm
);
3259 /* Use a block move to handle potentially misaligned entry_parm. */
3261 push_to_sequence2 (all
->first_conversion_insn
,
3262 all
->last_conversion_insn
);
3263 to_conversion
= true;
3265 emit_block_move (dest
, src
,
3266 GEN_INT (int_size_in_bytes (data
->passed_type
)),
3270 emit_move_insn (dest
, src
);
3275 all
->first_conversion_insn
= get_insns ();
3276 all
->last_conversion_insn
= get_last_insn ();
3280 SET_DECL_RTL (parm
, data
->stack_parm
);
3283 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3284 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3287 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
,
3291 tree orig_fnargs
= all
->orig_fnargs
;
3294 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
), ++i
)
3296 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3297 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3299 rtx tmp
, real
, imag
;
3300 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3302 real
= DECL_RTL (fnargs
[i
]);
3303 imag
= DECL_RTL (fnargs
[i
+ 1]);
3304 if (inner
!= GET_MODE (real
))
3306 real
= gen_lowpart_SUBREG (inner
, real
);
3307 imag
= gen_lowpart_SUBREG (inner
, imag
);
3310 if (TREE_ADDRESSABLE (parm
))
3313 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3314 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3316 TYPE_ALIGN (TREE_TYPE (parm
)));
3318 /* split_complex_arg put the real and imag parts in
3319 pseudos. Move them to memory. */
3320 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3321 set_mem_attributes (tmp
, parm
, 1);
3322 rmem
= adjust_address_nv (tmp
, inner
, 0);
3323 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3324 push_to_sequence2 (all
->first_conversion_insn
,
3325 all
->last_conversion_insn
);
3326 emit_move_insn (rmem
, real
);
3327 emit_move_insn (imem
, imag
);
3328 all
->first_conversion_insn
= get_insns ();
3329 all
->last_conversion_insn
= get_last_insn ();
3333 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3334 SET_DECL_RTL (parm
, tmp
);
3336 real
= DECL_INCOMING_RTL (fnargs
[i
]);
3337 imag
= DECL_INCOMING_RTL (fnargs
[i
+ 1]);
3338 if (inner
!= GET_MODE (real
))
3340 real
= gen_lowpart_SUBREG (inner
, real
);
3341 imag
= gen_lowpart_SUBREG (inner
, imag
);
3343 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3344 set_decl_incoming_rtl (parm
, tmp
, false);
3350 /* Assign RTL expressions to the function's parameters. This may involve
3351 copying them into registers and using those registers as the DECL_RTL. */
3354 assign_parms (tree fndecl
)
3356 struct assign_parm_data_all all
;
3361 crtl
->args
.internal_arg_pointer
3362 = targetm
.calls
.internal_arg_pointer ();
3364 assign_parms_initialize_all (&all
);
3365 fnargs
= assign_parms_augmented_arg_list (&all
);
3367 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3369 struct assign_parm_data_one data
;
3371 /* Extract the type of PARM; adjust it according to ABI. */
3372 assign_parm_find_data_types (&all
, parm
, &data
);
3374 /* Early out for errors and void parameters. */
3375 if (data
.passed_mode
== VOIDmode
)
3377 SET_DECL_RTL (parm
, const0_rtx
);
3378 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3382 /* Estimate stack alignment from parameter alignment. */
3383 if (SUPPORTS_STACK_ALIGNMENT
)
3386 = targetm
.calls
.function_arg_boundary (data
.promoted_mode
,
3388 align
= MINIMUM_ALIGNMENT (data
.passed_type
, data
.promoted_mode
,
3390 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3391 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3392 TYPE_MODE (data
.nominal_type
),
3393 TYPE_ALIGN (data
.nominal_type
));
3394 if (crtl
->stack_alignment_estimated
< align
)
3396 gcc_assert (!crtl
->stack_realign_processed
);
3397 crtl
->stack_alignment_estimated
= align
;
3401 if (cfun
->stdarg
&& !DECL_CHAIN (parm
))
3402 assign_parms_setup_varargs (&all
, &data
, false);
3404 /* Find out where the parameter arrives in this function. */
3405 assign_parm_find_entry_rtl (&all
, &data
);
3407 /* Find out where stack space for this parameter might be. */
3408 if (assign_parm_is_stack_parm (&all
, &data
))
3410 assign_parm_find_stack_rtl (parm
, &data
);
3411 assign_parm_adjust_entry_rtl (&data
);
3414 /* Record permanently how this parm was passed. */
3415 if (data
.passed_pointer
)
3418 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
.passed_type
)),
3420 set_decl_incoming_rtl (parm
, incoming_rtl
, true);
3423 set_decl_incoming_rtl (parm
, data
.entry_parm
, false);
3425 /* Update info on where next arg arrives in registers. */
3426 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.promoted_mode
,
3427 data
.passed_type
, data
.named_arg
);
3429 assign_parm_adjust_stack_rtl (&data
);
3431 if (assign_parm_setup_block_p (&data
))
3432 assign_parm_setup_block (&all
, parm
, &data
);
3433 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3434 assign_parm_setup_reg (&all
, parm
, &data
);
3436 assign_parm_setup_stack (&all
, parm
, &data
);
3439 if (targetm
.calls
.split_complex_arg
)
3440 assign_parms_unsplit_complex (&all
, fnargs
);
3444 /* Output all parameter conversion instructions (possibly including calls)
3445 now that all parameters have been copied out of hard registers. */
3446 emit_insn (all
.first_conversion_insn
);
3448 /* Estimate reload stack alignment from scalar return mode. */
3449 if (SUPPORTS_STACK_ALIGNMENT
)
3451 if (DECL_RESULT (fndecl
))
3453 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3454 enum machine_mode mode
= TYPE_MODE (type
);
3458 && !AGGREGATE_TYPE_P (type
))
3460 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3461 if (crtl
->stack_alignment_estimated
< align
)
3463 gcc_assert (!crtl
->stack_realign_processed
);
3464 crtl
->stack_alignment_estimated
= align
;
3470 /* If we are receiving a struct value address as the first argument, set up
3471 the RTL for the function result. As this might require code to convert
3472 the transmitted address to Pmode, we do this here to ensure that possible
3473 preliminary conversions of the address have been emitted already. */
3474 if (all
.function_result_decl
)
3476 tree result
= DECL_RESULT (current_function_decl
);
3477 rtx addr
= DECL_RTL (all
.function_result_decl
);
3480 if (DECL_BY_REFERENCE (result
))
3482 SET_DECL_VALUE_EXPR (result
, all
.function_result_decl
);
3487 SET_DECL_VALUE_EXPR (result
,
3488 build1 (INDIRECT_REF
, TREE_TYPE (result
),
3489 all
.function_result_decl
));
3490 addr
= convert_memory_address (Pmode
, addr
);
3491 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3492 set_mem_attributes (x
, result
, 1);
3495 DECL_HAS_VALUE_EXPR_P (result
) = 1;
3497 SET_DECL_RTL (result
, x
);
3500 /* We have aligned all the args, so add space for the pretend args. */
3501 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3502 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3503 crtl
->args
.size
= all
.stack_args_size
.constant
;
3505 /* Adjust function incoming argument size for alignment and
3508 crtl
->args
.size
= MAX (crtl
->args
.size
, all
.reg_parm_stack_space
);
3509 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3510 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3512 #ifdef ARGS_GROW_DOWNWARD
3513 crtl
->args
.arg_offset_rtx
3514 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3515 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3516 size_int (-all
.stack_args_size
.constant
)),
3517 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3519 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3522 /* See how many bytes, if any, of its args a function should try to pop
3525 crtl
->args
.pops_args
= targetm
.calls
.return_pops_args (fndecl
,
3529 /* For stdarg.h function, save info about
3530 regs and stack space used by the named args. */
3532 crtl
->args
.info
= all
.args_so_far_v
;
3534 /* Set the rtx used for the function return value. Put this in its
3535 own variable so any optimizers that need this information don't have
3536 to include tree.h. Do this here so it gets done when an inlined
3537 function gets output. */
3540 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3541 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3543 /* If scalar return value was computed in a pseudo-reg, or was a named
3544 return value that got dumped to the stack, copy that to the hard
3546 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3548 tree decl_result
= DECL_RESULT (fndecl
);
3549 rtx decl_rtl
= DECL_RTL (decl_result
);
3551 if (REG_P (decl_rtl
)
3552 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3553 : DECL_REGISTER (decl_result
))
3557 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3559 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3560 /* The delay slot scheduler assumes that crtl->return_rtx
3561 holds the hard register containing the return value, not a
3562 temporary pseudo. */
3563 crtl
->return_rtx
= real_decl_rtl
;
3568 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3569 For all seen types, gimplify their sizes. */
3572 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3579 if (POINTER_TYPE_P (t
))
3581 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3582 && !TYPE_SIZES_GIMPLIFIED (t
))
3584 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3592 /* Gimplify the parameter list for current_function_decl. This involves
3593 evaluating SAVE_EXPRs of variable sized parameters and generating code
3594 to implement callee-copies reference parameters. Returns a sequence of
3595 statements to add to the beginning of the function. */
3598 gimplify_parameters (void)
3600 struct assign_parm_data_all all
;
3602 gimple_seq stmts
= NULL
;
3606 assign_parms_initialize_all (&all
);
3607 fnargs
= assign_parms_augmented_arg_list (&all
);
3609 FOR_EACH_VEC_ELT (fnargs
, i
, parm
)
3611 struct assign_parm_data_one data
;
3613 /* Extract the type of PARM; adjust it according to ABI. */
3614 assign_parm_find_data_types (&all
, parm
, &data
);
3616 /* Early out for errors and void parameters. */
3617 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3620 /* Update info on where next arg arrives in registers. */
3621 targetm
.calls
.function_arg_advance (all
.args_so_far
, data
.promoted_mode
,
3622 data
.passed_type
, data
.named_arg
);
3624 /* ??? Once upon a time variable_size stuffed parameter list
3625 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3626 turned out to be less than manageable in the gimple world.
3627 Now we have to hunt them down ourselves. */
3628 walk_tree_without_duplicates (&data
.passed_type
,
3629 gimplify_parm_type
, &stmts
);
3631 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3633 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3634 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3637 if (data
.passed_pointer
)
3639 tree type
= TREE_TYPE (data
.passed_type
);
3640 if (reference_callee_copied (&all
.args_so_far_v
, TYPE_MODE (type
),
3641 type
, data
.named_arg
))
3645 /* For constant-sized objects, this is trivial; for
3646 variable-sized objects, we have to play games. */
3647 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3648 && !(flag_stack_check
== GENERIC_STACK_CHECK
3649 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3650 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3652 local
= create_tmp_var (type
, get_name (parm
));
3653 DECL_IGNORED_P (local
) = 0;
3654 /* If PARM was addressable, move that flag over
3655 to the local copy, as its address will be taken,
3656 not the PARMs. Keep the parms address taken
3657 as we'll query that flag during gimplification. */
3658 if (TREE_ADDRESSABLE (parm
))
3659 TREE_ADDRESSABLE (local
) = 1;
3660 else if (TREE_CODE (type
) == COMPLEX_TYPE
3661 || TREE_CODE (type
) == VECTOR_TYPE
)
3662 DECL_GIMPLE_REG_P (local
) = 1;
3666 tree ptr_type
, addr
;
3668 ptr_type
= build_pointer_type (type
);
3669 addr
= create_tmp_reg (ptr_type
, get_name (parm
));
3670 DECL_IGNORED_P (addr
) = 0;
3671 local
= build_fold_indirect_ref (addr
);
3673 t
= builtin_decl_explicit (BUILT_IN_ALLOCA_WITH_ALIGN
);
3674 t
= build_call_expr (t
, 2, DECL_SIZE_UNIT (parm
),
3675 size_int (DECL_ALIGN (parm
)));
3677 /* The call has been built for a variable-sized object. */
3678 CALL_ALLOCA_FOR_VAR_P (t
) = 1;
3679 t
= fold_convert (ptr_type
, t
);
3680 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3681 gimplify_and_add (t
, &stmts
);
3684 gimplify_assign (local
, parm
, &stmts
);
3686 SET_DECL_VALUE_EXPR (parm
, local
);
3687 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3697 /* Compute the size and offset from the start of the stacked arguments for a
3698 parm passed in mode PASSED_MODE and with type TYPE.
3700 INITIAL_OFFSET_PTR points to the current offset into the stacked
3703 The starting offset and size for this parm are returned in
3704 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3705 nonzero, the offset is that of stack slot, which is returned in
3706 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3707 padding required from the initial offset ptr to the stack slot.
3709 IN_REGS is nonzero if the argument will be passed in registers. It will
3710 never be set if REG_PARM_STACK_SPACE is not defined.
3712 REG_PARM_STACK_SPACE is the number of bytes of stack space reserved
3713 for arguments which are passed in registers.
3715 FNDECL is the function in which the argument was defined.
3717 There are two types of rounding that are done. The first, controlled by
3718 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3719 argument list to be aligned to the specific boundary (in bits). This
3720 rounding affects the initial and starting offsets, but not the argument
3723 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3724 optionally rounds the size of the parm to PARM_BOUNDARY. The
3725 initial offset is not affected by this rounding, while the size always
3726 is and the starting offset may be. */
3728 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3729 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3730 callers pass in the total size of args so far as
3731 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3734 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3735 int reg_parm_stack_space
, int partial
,
3736 tree fndecl ATTRIBUTE_UNUSED
,
3737 struct args_size
*initial_offset_ptr
,
3738 struct locate_and_pad_arg_data
*locate
)
3741 enum direction where_pad
;
3742 unsigned int boundary
, round_boundary
;
3743 int part_size_in_regs
;
3745 /* If we have found a stack parm before we reach the end of the
3746 area reserved for registers, skip that area. */
3749 if (reg_parm_stack_space
> 0)
3751 if (initial_offset_ptr
->var
)
3753 initial_offset_ptr
->var
3754 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3755 ssize_int (reg_parm_stack_space
));
3756 initial_offset_ptr
->constant
= 0;
3758 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3759 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3763 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3766 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3767 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3768 boundary
= targetm
.calls
.function_arg_boundary (passed_mode
, type
);
3769 round_boundary
= targetm
.calls
.function_arg_round_boundary (passed_mode
,
3771 locate
->where_pad
= where_pad
;
3773 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3774 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3775 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3777 locate
->boundary
= boundary
;
3779 if (SUPPORTS_STACK_ALIGNMENT
)
3781 /* stack_alignment_estimated can't change after stack has been
3783 if (crtl
->stack_alignment_estimated
< boundary
)
3785 if (!crtl
->stack_realign_processed
)
3786 crtl
->stack_alignment_estimated
= boundary
;
3789 /* If stack is realigned and stack alignment value
3790 hasn't been finalized, it is OK not to increase
3791 stack_alignment_estimated. The bigger alignment
3792 requirement is recorded in stack_alignment_needed
3794 gcc_assert (!crtl
->stack_realign_finalized
3795 && crtl
->stack_realign_needed
);
3800 /* Remember if the outgoing parameter requires extra alignment on the
3801 calling function side. */
3802 if (crtl
->stack_alignment_needed
< boundary
)
3803 crtl
->stack_alignment_needed
= boundary
;
3804 if (crtl
->preferred_stack_boundary
< boundary
)
3805 crtl
->preferred_stack_boundary
= boundary
;
3807 #ifdef ARGS_GROW_DOWNWARD
3808 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3809 if (initial_offset_ptr
->var
)
3810 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3811 initial_offset_ptr
->var
);
3815 if (where_pad
!= none
3816 && (!tree_fits_uhwi_p (sizetree
)
3817 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
3818 s2
= round_up (s2
, round_boundary
/ BITS_PER_UNIT
);
3819 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3822 locate
->slot_offset
.constant
+= part_size_in_regs
;
3824 if (!in_regs
|| reg_parm_stack_space
> 0)
3825 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3826 &locate
->alignment_pad
);
3828 locate
->size
.constant
= (-initial_offset_ptr
->constant
3829 - locate
->slot_offset
.constant
);
3830 if (initial_offset_ptr
->var
)
3831 locate
->size
.var
= size_binop (MINUS_EXPR
,
3832 size_binop (MINUS_EXPR
,
3834 initial_offset_ptr
->var
),
3835 locate
->slot_offset
.var
);
3837 /* Pad_below needs the pre-rounded size to know how much to pad
3839 locate
->offset
= locate
->slot_offset
;
3840 if (where_pad
== downward
)
3841 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3843 #else /* !ARGS_GROW_DOWNWARD */
3844 if (!in_regs
|| reg_parm_stack_space
> 0)
3845 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3846 &locate
->alignment_pad
);
3847 locate
->slot_offset
= *initial_offset_ptr
;
3849 #ifdef PUSH_ROUNDING
3850 if (passed_mode
!= BLKmode
)
3851 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3854 /* Pad_below needs the pre-rounded size to know how much to pad below
3855 so this must be done before rounding up. */
3856 locate
->offset
= locate
->slot_offset
;
3857 if (where_pad
== downward
)
3858 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3860 if (where_pad
!= none
3861 && (!tree_fits_uhwi_p (sizetree
)
3862 || (tree_to_uhwi (sizetree
) * BITS_PER_UNIT
) % round_boundary
))
3863 sizetree
= round_up (sizetree
, round_boundary
/ BITS_PER_UNIT
);
3865 ADD_PARM_SIZE (locate
->size
, sizetree
);
3867 locate
->size
.constant
-= part_size_in_regs
;
3868 #endif /* ARGS_GROW_DOWNWARD */
3870 #ifdef FUNCTION_ARG_OFFSET
3871 locate
->offset
.constant
+= FUNCTION_ARG_OFFSET (passed_mode
, type
);
3875 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3876 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3879 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3880 struct args_size
*alignment_pad
)
3882 tree save_var
= NULL_TREE
;
3883 HOST_WIDE_INT save_constant
= 0;
3884 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3885 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3887 #ifdef SPARC_STACK_BOUNDARY_HACK
3888 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3889 the real alignment of %sp. However, when it does this, the
3890 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3891 if (SPARC_STACK_BOUNDARY_HACK
)
3895 if (boundary
> PARM_BOUNDARY
)
3897 save_var
= offset_ptr
->var
;
3898 save_constant
= offset_ptr
->constant
;
3901 alignment_pad
->var
= NULL_TREE
;
3902 alignment_pad
->constant
= 0;
3904 if (boundary
> BITS_PER_UNIT
)
3906 if (offset_ptr
->var
)
3908 tree sp_offset_tree
= ssize_int (sp_offset
);
3909 tree offset
= size_binop (PLUS_EXPR
,
3910 ARGS_SIZE_TREE (*offset_ptr
),
3912 #ifdef ARGS_GROW_DOWNWARD
3913 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3915 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3918 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3919 /* ARGS_SIZE_TREE includes constant term. */
3920 offset_ptr
->constant
= 0;
3921 if (boundary
> PARM_BOUNDARY
)
3922 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3927 offset_ptr
->constant
= -sp_offset
+
3928 #ifdef ARGS_GROW_DOWNWARD
3929 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3931 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3933 if (boundary
> PARM_BOUNDARY
)
3934 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3940 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3942 if (passed_mode
!= BLKmode
)
3944 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3945 offset_ptr
->constant
3946 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3947 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3948 - GET_MODE_SIZE (passed_mode
));
3952 if (TREE_CODE (sizetree
) != INTEGER_CST
3953 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3955 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3956 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3958 ADD_PARM_SIZE (*offset_ptr
, s2
);
3959 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3965 /* True if register REGNO was alive at a place where `setjmp' was
3966 called and was set more than once or is an argument. Such regs may
3967 be clobbered by `longjmp'. */
3970 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3972 /* There appear to be cases where some local vars never reach the
3973 backend but have bogus regnos. */
3974 if (regno
>= max_reg_num ())
3977 return ((REG_N_SETS (regno
) > 1
3978 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR_FOR_FN (cfun
)),
3980 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3983 /* Walk the tree of blocks describing the binding levels within a
3984 function and warn about variables the might be killed by setjmp or
3985 vfork. This is done after calling flow_analysis before register
3986 allocation since that will clobber the pseudo-regs to hard
3990 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3994 for (decl
= BLOCK_VARS (block
); decl
; decl
= DECL_CHAIN (decl
))
3996 if (TREE_CODE (decl
) == VAR_DECL
3997 && DECL_RTL_SET_P (decl
)
3998 && REG_P (DECL_RTL (decl
))
3999 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4000 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
4001 " %<longjmp%> or %<vfork%>", decl
);
4004 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
4005 setjmp_vars_warning (setjmp_crosses
, sub
);
4008 /* Do the appropriate part of setjmp_vars_warning
4009 but for arguments instead of local variables. */
4012 setjmp_args_warning (bitmap setjmp_crosses
)
4015 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4016 decl
; decl
= DECL_CHAIN (decl
))
4017 if (DECL_RTL (decl
) != 0
4018 && REG_P (DECL_RTL (decl
))
4019 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4020 warning (OPT_Wclobbered
,
4021 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4025 /* Generate warning messages for variables live across setjmp. */
4028 generate_setjmp_warnings (void)
4030 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
4032 if (n_basic_blocks_for_fn (cfun
) == NUM_FIXED_BLOCKS
4033 || bitmap_empty_p (setjmp_crosses
))
4036 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
4037 setjmp_args_warning (setjmp_crosses
);
4041 /* Reverse the order of elements in the fragment chain T of blocks,
4042 and return the new head of the chain (old last element).
4043 In addition to that clear BLOCK_SAME_RANGE flags when needed
4044 and adjust BLOCK_SUPERCONTEXT from the super fragment to
4045 its super fragment origin. */
4048 block_fragments_nreverse (tree t
)
4050 tree prev
= 0, block
, next
, prev_super
= 0;
4051 tree super
= BLOCK_SUPERCONTEXT (t
);
4052 if (BLOCK_FRAGMENT_ORIGIN (super
))
4053 super
= BLOCK_FRAGMENT_ORIGIN (super
);
4054 for (block
= t
; block
; block
= next
)
4056 next
= BLOCK_FRAGMENT_CHAIN (block
);
4057 BLOCK_FRAGMENT_CHAIN (block
) = prev
;
4058 if ((prev
&& !BLOCK_SAME_RANGE (prev
))
4059 || (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (block
))
4061 BLOCK_SAME_RANGE (block
) = 0;
4062 prev_super
= BLOCK_SUPERCONTEXT (block
);
4063 BLOCK_SUPERCONTEXT (block
) = super
;
4066 t
= BLOCK_FRAGMENT_ORIGIN (t
);
4067 if (BLOCK_FRAGMENT_CHAIN (BLOCK_SUPERCONTEXT (t
))
4069 BLOCK_SAME_RANGE (t
) = 0;
4070 BLOCK_SUPERCONTEXT (t
) = super
;
4074 /* Reverse the order of elements in the chain T of blocks,
4075 and return the new head of the chain (old last element).
4076 Also do the same on subblocks and reverse the order of elements
4077 in BLOCK_FRAGMENT_CHAIN as well. */
4080 blocks_nreverse_all (tree t
)
4082 tree prev
= 0, block
, next
;
4083 for (block
= t
; block
; block
= next
)
4085 next
= BLOCK_CHAIN (block
);
4086 BLOCK_CHAIN (block
) = prev
;
4087 if (BLOCK_FRAGMENT_CHAIN (block
)
4088 && BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
)
4090 BLOCK_FRAGMENT_CHAIN (block
)
4091 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block
));
4092 if (!BLOCK_SAME_RANGE (BLOCK_FRAGMENT_CHAIN (block
)))
4093 BLOCK_SAME_RANGE (block
) = 0;
4095 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4102 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4103 and create duplicate blocks. */
4104 /* ??? Need an option to either create block fragments or to create
4105 abstract origin duplicates of a source block. It really depends
4106 on what optimization has been performed. */
4109 reorder_blocks (void)
4111 tree block
= DECL_INITIAL (current_function_decl
);
4113 if (block
== NULL_TREE
)
4116 auto_vec
<tree
, 10> block_stack
;
4118 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4119 clear_block_marks (block
);
4121 /* Prune the old trees away, so that they don't get in the way. */
4122 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
4123 BLOCK_CHAIN (block
) = NULL_TREE
;
4125 /* Recreate the block tree from the note nesting. */
4126 reorder_blocks_1 (get_insns (), block
, &block_stack
);
4127 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4130 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4133 clear_block_marks (tree block
)
4137 TREE_ASM_WRITTEN (block
) = 0;
4138 clear_block_marks (BLOCK_SUBBLOCKS (block
));
4139 block
= BLOCK_CHAIN (block
);
4144 reorder_blocks_1 (rtx insns
, tree current_block
, vec
<tree
> *p_block_stack
)
4147 tree prev_beg
= NULL_TREE
, prev_end
= NULL_TREE
;
4149 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
4153 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
4155 tree block
= NOTE_BLOCK (insn
);
4158 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
);
4162 BLOCK_SAME_RANGE (prev_end
) = 0;
4163 prev_end
= NULL_TREE
;
4165 /* If we have seen this block before, that means it now
4166 spans multiple address regions. Create a new fragment. */
4167 if (TREE_ASM_WRITTEN (block
))
4169 tree new_block
= copy_node (block
);
4171 BLOCK_SAME_RANGE (new_block
) = 0;
4172 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
4173 BLOCK_FRAGMENT_CHAIN (new_block
)
4174 = BLOCK_FRAGMENT_CHAIN (origin
);
4175 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
4177 NOTE_BLOCK (insn
) = new_block
;
4181 if (prev_beg
== current_block
&& prev_beg
)
4182 BLOCK_SAME_RANGE (block
) = 1;
4186 BLOCK_SUBBLOCKS (block
) = 0;
4187 TREE_ASM_WRITTEN (block
) = 1;
4188 /* When there's only one block for the entire function,
4189 current_block == block and we mustn't do this, it
4190 will cause infinite recursion. */
4191 if (block
!= current_block
)
4194 if (block
!= origin
)
4195 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
4196 || BLOCK_FRAGMENT_ORIGIN (BLOCK_SUPERCONTEXT
4199 if (p_block_stack
->is_empty ())
4200 super
= current_block
;
4203 super
= p_block_stack
->last ();
4204 gcc_assert (super
== current_block
4205 || BLOCK_FRAGMENT_ORIGIN (super
)
4208 BLOCK_SUPERCONTEXT (block
) = super
;
4209 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
4210 BLOCK_SUBBLOCKS (current_block
) = block
;
4211 current_block
= origin
;
4213 p_block_stack
->safe_push (block
);
4215 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
4217 NOTE_BLOCK (insn
) = p_block_stack
->pop ();
4218 current_block
= BLOCK_SUPERCONTEXT (current_block
);
4219 if (BLOCK_FRAGMENT_ORIGIN (current_block
))
4220 current_block
= BLOCK_FRAGMENT_ORIGIN (current_block
);
4221 prev_beg
= NULL_TREE
;
4222 prev_end
= BLOCK_SAME_RANGE (NOTE_BLOCK (insn
))
4223 ? NOTE_BLOCK (insn
) : NULL_TREE
;
4228 prev_beg
= NULL_TREE
;
4230 BLOCK_SAME_RANGE (prev_end
) = 0;
4231 prev_end
= NULL_TREE
;
4236 /* Reverse the order of elements in the chain T of blocks,
4237 and return the new head of the chain (old last element). */
4240 blocks_nreverse (tree t
)
4242 tree prev
= 0, block
, next
;
4243 for (block
= t
; block
; block
= next
)
4245 next
= BLOCK_CHAIN (block
);
4246 BLOCK_CHAIN (block
) = prev
;
4252 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4253 by modifying the last node in chain 1 to point to chain 2. */
4256 block_chainon (tree op1
, tree op2
)
4265 for (t1
= op1
; BLOCK_CHAIN (t1
); t1
= BLOCK_CHAIN (t1
))
4267 BLOCK_CHAIN (t1
) = op2
;
4269 #ifdef ENABLE_TREE_CHECKING
4272 for (t2
= op2
; t2
; t2
= BLOCK_CHAIN (t2
))
4273 gcc_assert (t2
!= t1
);
4280 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4281 non-NULL, list them all into VECTOR, in a depth-first preorder
4282 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4286 all_blocks (tree block
, tree
*vector
)
4292 TREE_ASM_WRITTEN (block
) = 0;
4294 /* Record this block. */
4296 vector
[n_blocks
] = block
;
4300 /* Record the subblocks, and their subblocks... */
4301 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
4302 vector
? vector
+ n_blocks
: 0);
4303 block
= BLOCK_CHAIN (block
);
4309 /* Return a vector containing all the blocks rooted at BLOCK. The
4310 number of elements in the vector is stored in N_BLOCKS_P. The
4311 vector is dynamically allocated; it is the caller's responsibility
4312 to call `free' on the pointer returned. */
4315 get_block_vector (tree block
, int *n_blocks_p
)
4319 *n_blocks_p
= all_blocks (block
, NULL
);
4320 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
4321 all_blocks (block
, block_vector
);
4323 return block_vector
;
4326 static GTY(()) int next_block_index
= 2;
4328 /* Set BLOCK_NUMBER for all the blocks in FN. */
4331 number_blocks (tree fn
)
4337 /* For SDB and XCOFF debugging output, we start numbering the blocks
4338 from 1 within each function, rather than keeping a running
4340 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4341 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
4342 next_block_index
= 1;
4345 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
4347 /* The top-level BLOCK isn't numbered at all. */
4348 for (i
= 1; i
< n_blocks
; ++i
)
4349 /* We number the blocks from two. */
4350 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
4352 free (block_vector
);
4357 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4360 debug_find_var_in_block_tree (tree var
, tree block
)
4364 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4368 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4370 tree ret
= debug_find_var_in_block_tree (var
, t
);
4378 /* Keep track of whether we're in a dummy function context. If we are,
4379 we don't want to invoke the set_current_function hook, because we'll
4380 get into trouble if the hook calls target_reinit () recursively or
4381 when the initial initialization is not yet complete. */
4383 static bool in_dummy_function
;
4385 /* Invoke the target hook when setting cfun. Update the optimization options
4386 if the function uses different options than the default. */
4389 invoke_set_current_function_hook (tree fndecl
)
4391 if (!in_dummy_function
)
4393 tree opts
= ((fndecl
)
4394 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4395 : optimization_default_node
);
4398 opts
= optimization_default_node
;
4400 /* Change optimization options if needed. */
4401 if (optimization_current_node
!= opts
)
4403 optimization_current_node
= opts
;
4404 cl_optimization_restore (&global_options
, TREE_OPTIMIZATION (opts
));
4407 targetm
.set_current_function (fndecl
);
4408 this_fn_optabs
= this_target_optabs
;
4410 if (opts
!= optimization_default_node
)
4412 init_tree_optimization_optabs (opts
);
4413 if (TREE_OPTIMIZATION_OPTABS (opts
))
4414 this_fn_optabs
= (struct target_optabs
*)
4415 TREE_OPTIMIZATION_OPTABS (opts
);
4420 /* cfun should never be set directly; use this function. */
4423 set_cfun (struct function
*new_cfun
)
4425 if (cfun
!= new_cfun
)
4428 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4432 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4434 static vec
<function_p
> cfun_stack
;
4436 /* Push the current cfun onto the stack, and set cfun to new_cfun. Also set
4437 current_function_decl accordingly. */
4440 push_cfun (struct function
*new_cfun
)
4442 gcc_assert ((!cfun
&& !current_function_decl
)
4443 || (cfun
&& current_function_decl
== cfun
->decl
));
4444 cfun_stack
.safe_push (cfun
);
4445 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4446 set_cfun (new_cfun
);
4449 /* Pop cfun from the stack. Also set current_function_decl accordingly. */
4454 struct function
*new_cfun
= cfun_stack
.pop ();
4455 /* When in_dummy_function, we do have a cfun but current_function_decl is
4456 NULL. We also allow pushing NULL cfun and subsequently changing
4457 current_function_decl to something else and have both restored by
4459 gcc_checking_assert (in_dummy_function
4461 || current_function_decl
== cfun
->decl
);
4462 set_cfun (new_cfun
);
4463 current_function_decl
= new_cfun
? new_cfun
->decl
: NULL_TREE
;
4466 /* Return value of funcdef and increase it. */
4468 get_next_funcdef_no (void)
4470 return funcdef_no
++;
4473 /* Return value of funcdef. */
4475 get_last_funcdef_no (void)
4480 /* Allocate a function structure for FNDECL and set its contents
4481 to the defaults. Set cfun to the newly-allocated object.
4482 Some of the helper functions invoked during initialization assume
4483 that cfun has already been set. Therefore, assign the new object
4484 directly into cfun and invoke the back end hook explicitly at the
4485 very end, rather than initializing a temporary and calling set_cfun
4488 ABSTRACT_P is true if this is a function that will never be seen by
4489 the middle-end. Such functions are front-end concepts (like C++
4490 function templates) that do not correspond directly to functions
4491 placed in object files. */
4494 allocate_struct_function (tree fndecl
, bool abstract_p
)
4496 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4498 cfun
= ggc_alloc_cleared_function ();
4500 init_eh_for_function ();
4502 if (init_machine_status
)
4503 cfun
->machine
= (*init_machine_status
) ();
4505 #ifdef OVERRIDE_ABI_FORMAT
4506 OVERRIDE_ABI_FORMAT (fndecl
);
4509 if (fndecl
!= NULL_TREE
)
4511 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4512 cfun
->decl
= fndecl
;
4513 current_function_funcdef_no
= get_next_funcdef_no ();
4516 invoke_set_current_function_hook (fndecl
);
4518 if (fndecl
!= NULL_TREE
)
4520 tree result
= DECL_RESULT (fndecl
);
4521 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4523 #ifdef PCC_STATIC_STRUCT_RETURN
4524 cfun
->returns_pcc_struct
= 1;
4526 cfun
->returns_struct
= 1;
4529 cfun
->stdarg
= stdarg_p (fntype
);
4531 /* Assume all registers in stdarg functions need to be saved. */
4532 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4533 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4535 /* ??? This could be set on a per-function basis by the front-end
4536 but is this worth the hassle? */
4537 cfun
->can_throw_non_call_exceptions
= flag_non_call_exceptions
;
4541 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4542 instead of just setting it. */
4545 push_struct_function (tree fndecl
)
4547 /* When in_dummy_function we might be in the middle of a pop_cfun and
4548 current_function_decl and cfun may not match. */
4549 gcc_assert (in_dummy_function
4550 || (!cfun
&& !current_function_decl
)
4551 || (cfun
&& current_function_decl
== cfun
->decl
));
4552 cfun_stack
.safe_push (cfun
);
4553 current_function_decl
= fndecl
;
4554 allocate_struct_function (fndecl
, false);
4557 /* Reset crtl and other non-struct-function variables to defaults as
4558 appropriate for emitting rtl at the start of a function. */
4561 prepare_function_start (void)
4563 gcc_assert (!crtl
->emit
.x_last_insn
);
4566 init_varasm_status ();
4568 default_rtl_profile ();
4570 if (flag_stack_usage_info
)
4572 cfun
->su
= ggc_alloc_cleared_stack_usage ();
4573 cfun
->su
->static_stack_size
= -1;
4576 cse_not_expected
= ! optimize
;
4578 /* Caller save not needed yet. */
4579 caller_save_needed
= 0;
4581 /* We haven't done register allocation yet. */
4584 /* Indicate that we have not instantiated virtual registers yet. */
4585 virtuals_instantiated
= 0;
4587 /* Indicate that we want CONCATs now. */
4588 generating_concat_p
= 1;
4590 /* Indicate we have no need of a frame pointer yet. */
4591 frame_pointer_needed
= 0;
4594 /* Initialize the rtl expansion mechanism so that we can do simple things
4595 like generate sequences. This is used to provide a context during global
4596 initialization of some passes. You must call expand_dummy_function_end
4597 to exit this context. */
4600 init_dummy_function_start (void)
4602 gcc_assert (!in_dummy_function
);
4603 in_dummy_function
= true;
4604 push_struct_function (NULL_TREE
);
4605 prepare_function_start ();
4608 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4609 and initialize static variables for generating RTL for the statements
4613 init_function_start (tree subr
)
4615 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4616 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4618 allocate_struct_function (subr
, false);
4619 prepare_function_start ();
4620 decide_function_section (subr
);
4622 /* Warn if this value is an aggregate type,
4623 regardless of which calling convention we are using for it. */
4624 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4625 warning (OPT_Waggregate_return
, "function returns an aggregate");
4628 /* Expand code to verify the stack_protect_guard. This is invoked at
4629 the end of a function to be protected. */
4631 #ifndef HAVE_stack_protect_test
4632 # define HAVE_stack_protect_test 0
4633 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4637 stack_protect_epilogue (void)
4639 tree guard_decl
= targetm
.stack_protect_guard ();
4640 rtx label
= gen_label_rtx ();
4643 x
= expand_normal (crtl
->stack_protect_guard
);
4644 y
= expand_normal (guard_decl
);
4646 /* Allow the target to compare Y with X without leaking either into
4648 switch (HAVE_stack_protect_test
!= 0)
4651 tmp
= gen_stack_protect_test (x
, y
, label
);
4660 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4664 /* The noreturn predictor has been moved to the tree level. The rtl-level
4665 predictors estimate this branch about 20%, which isn't enough to get
4666 things moved out of line. Since this is the only extant case of adding
4667 a noreturn function at the rtl level, it doesn't seem worth doing ought
4668 except adding the prediction by hand. */
4669 tmp
= get_last_insn ();
4671 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4673 expand_call (targetm
.stack_protect_fail (), NULL_RTX
, /*ignore=*/true);
4678 /* Start the RTL for a new function, and set variables used for
4680 SUBR is the FUNCTION_DECL node.
4681 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4682 the function's parameters, which must be run at any return statement. */
4685 expand_function_start (tree subr
)
4687 /* Make sure volatile mem refs aren't considered
4688 valid operands of arithmetic insns. */
4689 init_recog_no_volatile ();
4693 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4696 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4698 /* Make the label for return statements to jump to. Do not special
4699 case machines with special return instructions -- they will be
4700 handled later during jump, ifcvt, or epilogue creation. */
4701 return_label
= gen_label_rtx ();
4703 /* Initialize rtx used to return the value. */
4704 /* Do this before assign_parms so that we copy the struct value address
4705 before any library calls that assign parms might generate. */
4707 /* Decide whether to return the value in memory or in a register. */
4708 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4710 /* Returning something that won't go in a register. */
4711 rtx value_address
= 0;
4713 #ifdef PCC_STATIC_STRUCT_RETURN
4714 if (cfun
->returns_pcc_struct
)
4716 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4717 value_address
= assemble_static_space (size
);
4722 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4723 /* Expect to be passed the address of a place to store the value.
4724 If it is passed as an argument, assign_parms will take care of
4728 value_address
= gen_reg_rtx (Pmode
);
4729 emit_move_insn (value_address
, sv
);
4734 rtx x
= value_address
;
4735 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4737 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4738 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4740 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4743 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4744 /* If return mode is void, this decl rtl should not be used. */
4745 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4748 /* Compute the return values into a pseudo reg, which we will copy
4749 into the true return register after the cleanups are done. */
4750 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4751 if (TYPE_MODE (return_type
) != BLKmode
4752 && targetm
.calls
.return_in_msb (return_type
))
4753 /* expand_function_end will insert the appropriate padding in
4754 this case. Use the return value's natural (unpadded) mode
4755 within the function proper. */
4756 SET_DECL_RTL (DECL_RESULT (subr
),
4757 gen_reg_rtx (TYPE_MODE (return_type
)));
4760 /* In order to figure out what mode to use for the pseudo, we
4761 figure out what the mode of the eventual return register will
4762 actually be, and use that. */
4763 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4765 /* Structures that are returned in registers are not
4766 aggregate_value_p, so we may see a PARALLEL or a REG. */
4767 if (REG_P (hard_reg
))
4768 SET_DECL_RTL (DECL_RESULT (subr
),
4769 gen_reg_rtx (GET_MODE (hard_reg
)));
4772 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4773 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4777 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4778 result to the real return register(s). */
4779 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4782 /* Initialize rtx for parameters and local variables.
4783 In some cases this requires emitting insns. */
4784 assign_parms (subr
);
4786 /* If function gets a static chain arg, store it. */
4787 if (cfun
->static_chain_decl
)
4789 tree parm
= cfun
->static_chain_decl
;
4790 rtx local
, chain
, insn
;
4792 local
= gen_reg_rtx (Pmode
);
4793 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
4795 set_decl_incoming_rtl (parm
, chain
, false);
4796 SET_DECL_RTL (parm
, local
);
4797 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4799 insn
= emit_move_insn (local
, chain
);
4801 /* Mark the register as eliminable, similar to parameters. */
4803 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
4804 set_dst_reg_note (insn
, REG_EQUIV
, chain
, local
);
4807 /* If the function receives a non-local goto, then store the
4808 bits we need to restore the frame pointer. */
4809 if (cfun
->nonlocal_goto_save_area
)
4814 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4815 gcc_assert (DECL_RTL_SET_P (var
));
4817 t_save
= build4 (ARRAY_REF
,
4818 TREE_TYPE (TREE_TYPE (cfun
->nonlocal_goto_save_area
)),
4819 cfun
->nonlocal_goto_save_area
,
4820 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4821 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4822 gcc_assert (GET_MODE (r_save
) == Pmode
);
4824 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4825 update_nonlocal_goto_save_area ();
4828 /* The following was moved from init_function_start.
4829 The move is supposed to make sdb output more accurate. */
4830 /* Indicate the beginning of the function body,
4831 as opposed to parm setup. */
4832 emit_note (NOTE_INSN_FUNCTION_BEG
);
4834 gcc_assert (NOTE_P (get_last_insn ()));
4836 parm_birth_insn
= get_last_insn ();
4841 PROFILE_HOOK (current_function_funcdef_no
);
4845 /* If we are doing generic stack checking, the probe should go here. */
4846 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4847 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4850 /* Undo the effects of init_dummy_function_start. */
4852 expand_dummy_function_end (void)
4854 gcc_assert (in_dummy_function
);
4856 /* End any sequences that failed to be closed due to syntax errors. */
4857 while (in_sequence_p ())
4860 /* Outside function body, can't compute type's actual size
4861 until next function's body starts. */
4863 free_after_parsing (cfun
);
4864 free_after_compilation (cfun
);
4866 in_dummy_function
= false;
4869 /* Call DOIT for each hard register used as a return value from
4870 the current function. */
4873 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4875 rtx outgoing
= crtl
->return_rtx
;
4880 if (REG_P (outgoing
))
4881 (*doit
) (outgoing
, arg
);
4882 else if (GET_CODE (outgoing
) == PARALLEL
)
4886 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4888 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4890 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4897 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4903 clobber_return_register (void)
4905 diddle_return_value (do_clobber_return_reg
, NULL
);
4907 /* In case we do use pseudo to return value, clobber it too. */
4908 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4910 tree decl_result
= DECL_RESULT (current_function_decl
);
4911 rtx decl_rtl
= DECL_RTL (decl_result
);
4912 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4914 do_clobber_return_reg (decl_rtl
, NULL
);
4920 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4926 use_return_register (void)
4928 diddle_return_value (do_use_return_reg
, NULL
);
4931 /* Possibly warn about unused parameters. */
4933 do_warn_unused_parameter (tree fn
)
4937 for (decl
= DECL_ARGUMENTS (fn
);
4938 decl
; decl
= DECL_CHAIN (decl
))
4939 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4940 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4941 && !TREE_NO_WARNING (decl
))
4942 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4945 /* Set the location of the insn chain starting at INSN to LOC. */
4948 set_insn_locations (rtx insn
, int loc
)
4950 while (insn
!= NULL_RTX
)
4953 INSN_LOCATION (insn
) = loc
;
4954 insn
= NEXT_INSN (insn
);
4958 /* Generate RTL for the end of the current function. */
4961 expand_function_end (void)
4965 /* If arg_pointer_save_area was referenced only from a nested
4966 function, we will not have initialized it yet. Do that now. */
4967 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4968 get_arg_pointer_save_area ();
4970 /* If we are doing generic stack checking and this function makes calls,
4971 do a stack probe at the start of the function to ensure we have enough
4972 space for another stack frame. */
4973 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4977 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4980 rtx max_frame_size
= GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
);
4982 if (STACK_CHECK_MOVING_SP
)
4983 anti_adjust_stack_and_probe (max_frame_size
, true);
4985 probe_stack_range (STACK_OLD_CHECK_PROTECT
, max_frame_size
);
4988 set_insn_locations (seq
, prologue_location
);
4989 emit_insn_before (seq
, stack_check_probe_note
);
4994 /* End any sequences that failed to be closed due to syntax errors. */
4995 while (in_sequence_p ())
4998 clear_pending_stack_adjust ();
4999 do_pending_stack_adjust ();
5001 /* Output a linenumber for the end of the function.
5002 SDB depends on this. */
5003 set_curr_insn_location (input_location
);
5005 /* Before the return label (if any), clobber the return
5006 registers so that they are not propagated live to the rest of
5007 the function. This can only happen with functions that drop
5008 through; if there had been a return statement, there would
5009 have either been a return rtx, or a jump to the return label.
5011 We delay actual code generation after the current_function_value_rtx
5013 clobber_after
= get_last_insn ();
5015 /* Output the label for the actual return from the function. */
5016 emit_label (return_label
);
5018 if (targetm_common
.except_unwind_info (&global_options
) == UI_SJLJ
)
5020 /* Let except.c know where it should emit the call to unregister
5021 the function context for sjlj exceptions. */
5022 if (flag_exceptions
)
5023 sjlj_emit_function_exit_after (get_last_insn ());
5027 /* We want to ensure that instructions that may trap are not
5028 moved into the epilogue by scheduling, because we don't
5029 always emit unwind information for the epilogue. */
5030 if (cfun
->can_throw_non_call_exceptions
)
5031 emit_insn (gen_blockage ());
5034 /* If this is an implementation of throw, do what's necessary to
5035 communicate between __builtin_eh_return and the epilogue. */
5036 expand_eh_return ();
5038 /* If scalar return value was computed in a pseudo-reg, or was a named
5039 return value that got dumped to the stack, copy that to the hard
5041 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5043 tree decl_result
= DECL_RESULT (current_function_decl
);
5044 rtx decl_rtl
= DECL_RTL (decl_result
);
5046 if (REG_P (decl_rtl
)
5047 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
5048 : DECL_REGISTER (decl_result
))
5050 rtx real_decl_rtl
= crtl
->return_rtx
;
5052 /* This should be set in assign_parms. */
5053 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
5055 /* If this is a BLKmode structure being returned in registers,
5056 then use the mode computed in expand_return. Note that if
5057 decl_rtl is memory, then its mode may have been changed,
5058 but that crtl->return_rtx has not. */
5059 if (GET_MODE (real_decl_rtl
) == BLKmode
)
5060 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
5062 /* If a non-BLKmode return value should be padded at the least
5063 significant end of the register, shift it left by the appropriate
5064 amount. BLKmode results are handled using the group load/store
5066 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
5067 && REG_P (real_decl_rtl
)
5068 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
5070 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
5071 REGNO (real_decl_rtl
)),
5073 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
5075 /* If a named return value dumped decl_return to memory, then
5076 we may need to re-do the PROMOTE_MODE signed/unsigned
5078 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
5080 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
5081 promote_function_mode (TREE_TYPE (decl_result
),
5082 GET_MODE (decl_rtl
), &unsignedp
,
5083 TREE_TYPE (current_function_decl
), 1);
5085 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
5087 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
5089 /* If expand_function_start has created a PARALLEL for decl_rtl,
5090 move the result to the real return registers. Otherwise, do
5091 a group load from decl_rtl for a named return. */
5092 if (GET_CODE (decl_rtl
) == PARALLEL
)
5093 emit_group_move (real_decl_rtl
, decl_rtl
);
5095 emit_group_load (real_decl_rtl
, decl_rtl
,
5096 TREE_TYPE (decl_result
),
5097 int_size_in_bytes (TREE_TYPE (decl_result
)));
5099 /* In the case of complex integer modes smaller than a word, we'll
5100 need to generate some non-trivial bitfield insertions. Do that
5101 on a pseudo and not the hard register. */
5102 else if (GET_CODE (decl_rtl
) == CONCAT
5103 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
5104 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
5106 int old_generating_concat_p
;
5109 old_generating_concat_p
= generating_concat_p
;
5110 generating_concat_p
= 0;
5111 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
5112 generating_concat_p
= old_generating_concat_p
;
5114 emit_move_insn (tmp
, decl_rtl
);
5115 emit_move_insn (real_decl_rtl
, tmp
);
5118 emit_move_insn (real_decl_rtl
, decl_rtl
);
5122 /* If returning a structure, arrange to return the address of the value
5123 in a place where debuggers expect to find it.
5125 If returning a structure PCC style,
5126 the caller also depends on this value.
5127 And cfun->returns_pcc_struct is not necessarily set. */
5128 if (cfun
->returns_struct
5129 || cfun
->returns_pcc_struct
)
5131 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
5132 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5135 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
5136 type
= TREE_TYPE (type
);
5138 value_address
= XEXP (value_address
, 0);
5140 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
5141 current_function_decl
, true);
5143 /* Mark this as a function return value so integrate will delete the
5144 assignment and USE below when inlining this function. */
5145 REG_FUNCTION_VALUE_P (outgoing
) = 1;
5147 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5148 value_address
= convert_memory_address (GET_MODE (outgoing
),
5151 emit_move_insn (outgoing
, value_address
);
5153 /* Show return register used to hold result (in this case the address
5155 crtl
->return_rtx
= outgoing
;
5158 /* Emit the actual code to clobber return register. Don't emit
5159 it if clobber_after is a barrier, then the previous basic block
5160 certainly doesn't fall thru into the exit block. */
5161 if (!BARRIER_P (clobber_after
))
5166 clobber_return_register ();
5170 emit_insn_after (seq
, clobber_after
);
5173 /* Output the label for the naked return from the function. */
5174 if (naked_return_label
)
5175 emit_label (naked_return_label
);
5177 /* @@@ This is a kludge. We want to ensure that instructions that
5178 may trap are not moved into the epilogue by scheduling, because
5179 we don't always emit unwind information for the epilogue. */
5180 if (cfun
->can_throw_non_call_exceptions
5181 && targetm_common
.except_unwind_info (&global_options
) != UI_SJLJ
)
5182 emit_insn (gen_blockage ());
5184 /* If stack protection is enabled for this function, check the guard. */
5185 if (crtl
->stack_protect_guard
)
5186 stack_protect_epilogue ();
5188 /* If we had calls to alloca, and this machine needs
5189 an accurate stack pointer to exit the function,
5190 insert some code to save and restore the stack pointer. */
5191 if (! EXIT_IGNORE_STACK
5192 && cfun
->calls_alloca
)
5197 emit_stack_save (SAVE_FUNCTION
, &tem
);
5200 emit_insn_before (seq
, parm_birth_insn
);
5202 emit_stack_restore (SAVE_FUNCTION
, tem
);
5205 /* ??? This should no longer be necessary since stupid is no longer with
5206 us, but there are some parts of the compiler (eg reload_combine, and
5207 sh mach_dep_reorg) that still try and compute their own lifetime info
5208 instead of using the general framework. */
5209 use_return_register ();
5213 get_arg_pointer_save_area (void)
5215 rtx ret
= arg_pointer_save_area
;
5219 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5220 arg_pointer_save_area
= ret
;
5223 if (! crtl
->arg_pointer_save_area_init
)
5227 /* Save the arg pointer at the beginning of the function. The
5228 generated stack slot may not be a valid memory address, so we
5229 have to check it and fix it if necessary. */
5231 emit_move_insn (validize_mem (ret
),
5232 crtl
->args
.internal_arg_pointer
);
5236 push_topmost_sequence ();
5237 emit_insn_after (seq
, entry_of_function ());
5238 pop_topmost_sequence ();
5240 crtl
->arg_pointer_save_area_init
= true;
5246 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5247 for the first time. */
5250 record_insns (rtx insns
, rtx end
, htab_t
*hashp
)
5253 htab_t hash
= *hashp
;
5257 = htab_create_ggc (17, htab_hash_pointer
, htab_eq_pointer
, NULL
);
5259 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
5261 void **slot
= htab_find_slot (hash
, tmp
, INSERT
);
5262 gcc_assert (*slot
== NULL
);
5267 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5268 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5269 insn, then record COPY as well. */
5272 maybe_copy_prologue_epilogue_insn (rtx insn
, rtx copy
)
5277 hash
= epilogue_insn_hash
;
5278 if (!hash
|| !htab_find (hash
, insn
))
5280 hash
= prologue_insn_hash
;
5281 if (!hash
|| !htab_find (hash
, insn
))
5285 slot
= htab_find_slot (hash
, copy
, INSERT
);
5286 gcc_assert (*slot
== NULL
);
5290 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5291 we can be running after reorg, SEQUENCE rtl is possible. */
5294 contains (const_rtx insn
, htab_t hash
)
5299 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5302 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
5303 if (htab_find (hash
, XVECEXP (PATTERN (insn
), 0, i
)))
5308 return htab_find (hash
, insn
) != NULL
;
5312 prologue_epilogue_contains (const_rtx insn
)
5314 if (contains (insn
, prologue_insn_hash
))
5316 if (contains (insn
, epilogue_insn_hash
))
5321 #ifdef HAVE_simple_return
5323 /* Return true if INSN requires the stack frame to be set up.
5324 PROLOGUE_USED contains the hard registers used in the function
5325 prologue. SET_UP_BY_PROLOGUE is the set of registers we expect the
5326 prologue to set up for the function. */
5328 requires_stack_frame_p (rtx insn
, HARD_REG_SET prologue_used
,
5329 HARD_REG_SET set_up_by_prologue
)
5332 HARD_REG_SET hardregs
;
5336 return !SIBLING_CALL_P (insn
);
5338 /* We need a frame to get the unique CFA expected by the unwinder. */
5339 if (cfun
->can_throw_non_call_exceptions
&& can_throw_internal (insn
))
5342 CLEAR_HARD_REG_SET (hardregs
);
5343 for (df_rec
= DF_INSN_DEFS (insn
); *df_rec
; df_rec
++)
5345 rtx dreg
= DF_REF_REG (*df_rec
);
5350 add_to_hard_reg_set (&hardregs
, GET_MODE (dreg
),
5353 if (hard_reg_set_intersect_p (hardregs
, prologue_used
))
5355 AND_COMPL_HARD_REG_SET (hardregs
, call_used_reg_set
);
5356 for (regno
= 0; regno
< FIRST_PSEUDO_REGISTER
; regno
++)
5357 if (TEST_HARD_REG_BIT (hardregs
, regno
)
5358 && df_regs_ever_live_p (regno
))
5361 for (df_rec
= DF_INSN_USES (insn
); *df_rec
; df_rec
++)
5363 rtx reg
= DF_REF_REG (*df_rec
);
5368 add_to_hard_reg_set (&hardregs
, GET_MODE (reg
),
5371 if (hard_reg_set_intersect_p (hardregs
, set_up_by_prologue
))
5377 /* See whether BB has a single successor that uses [REGNO, END_REGNO),
5378 and if BB is its only predecessor. Return that block if so,
5379 otherwise return null. */
5382 next_block_for_reg (basic_block bb
, int regno
, int end_regno
)
5390 FOR_EACH_EDGE (e
, ei
, bb
->succs
)
5392 live
= df_get_live_in (e
->dest
);
5393 for (i
= regno
; i
< end_regno
; i
++)
5394 if (REGNO_REG_SET_P (live
, i
))
5396 if (live_edge
&& live_edge
!= e
)
5402 /* We can sometimes encounter dead code. Don't try to move it
5403 into the exit block. */
5404 if (!live_edge
|| live_edge
->dest
== EXIT_BLOCK_PTR_FOR_FN (cfun
))
5407 /* Reject targets of abnormal edges. This is needed for correctness
5408 on ports like Alpha and MIPS, whose pic_offset_table_rtx can die on
5409 exception edges even though it is generally treated as call-saved
5410 for the majority of the compilation. Moving across abnormal edges
5411 isn't going to be interesting for shrink-wrap usage anyway. */
5412 if (live_edge
->flags
& EDGE_ABNORMAL
)
5415 if (EDGE_COUNT (live_edge
->dest
->preds
) > 1)
5418 return live_edge
->dest
;
5421 /* Try to move INSN from BB to a successor. Return true on success.
5422 USES and DEFS are the set of registers that are used and defined
5423 after INSN in BB. */
5426 move_insn_for_shrink_wrap (basic_block bb
, rtx insn
,
5427 const HARD_REG_SET uses
,
5428 const HARD_REG_SET defs
)
5431 bitmap live_out
, live_in
, bb_uses
, bb_defs
;
5432 unsigned int i
, dregno
, end_dregno
, sregno
, end_sregno
;
5433 basic_block next_block
;
5435 /* Look for a simple register copy. */
5436 set
= single_set (insn
);
5439 src
= SET_SRC (set
);
5440 dest
= SET_DEST (set
);
5441 if (!REG_P (dest
) || !REG_P (src
))
5444 /* Make sure that the source register isn't defined later in BB. */
5445 sregno
= REGNO (src
);
5446 end_sregno
= END_REGNO (src
);
5447 if (overlaps_hard_reg_set_p (defs
, GET_MODE (src
), sregno
))
5450 /* Make sure that the destination register isn't referenced later in BB. */
5451 dregno
= REGNO (dest
);
5452 end_dregno
= END_REGNO (dest
);
5453 if (overlaps_hard_reg_set_p (uses
, GET_MODE (dest
), dregno
)
5454 || overlaps_hard_reg_set_p (defs
, GET_MODE (dest
), dregno
))
5457 /* See whether there is a successor block to which we could move INSN. */
5458 next_block
= next_block_for_reg (bb
, dregno
, end_dregno
);
5462 /* At this point we are committed to moving INSN, but let's try to
5463 move it as far as we can. */
5466 live_out
= df_get_live_out (bb
);
5467 live_in
= df_get_live_in (next_block
);
5470 /* Check whether BB uses DEST or clobbers DEST. We need to add
5471 INSN to BB if so. Either way, DEST is no longer live on entry,
5472 except for any part that overlaps SRC (next loop). */
5473 bb_uses
= &DF_LR_BB_INFO (bb
)->use
;
5474 bb_defs
= &DF_LR_BB_INFO (bb
)->def
;
5477 for (i
= dregno
; i
< end_dregno
; i
++)
5479 if (REGNO_REG_SET_P (bb_uses
, i
) || REGNO_REG_SET_P (bb_defs
, i
)
5480 || REGNO_REG_SET_P (&DF_LIVE_BB_INFO (bb
)->gen
, i
))
5482 CLEAR_REGNO_REG_SET (live_out
, i
);
5483 CLEAR_REGNO_REG_SET (live_in
, i
);
5486 /* Check whether BB clobbers SRC. We need to add INSN to BB if so.
5487 Either way, SRC is now live on entry. */
5488 for (i
= sregno
; i
< end_sregno
; i
++)
5490 if (REGNO_REG_SET_P (bb_defs
, i
)
5491 || REGNO_REG_SET_P (&DF_LIVE_BB_INFO (bb
)->gen
, i
))
5493 SET_REGNO_REG_SET (live_out
, i
);
5494 SET_REGNO_REG_SET (live_in
, i
);
5499 /* DF_LR_BB_INFO (bb)->def does not comprise the DF_REF_PARTIAL and
5500 DF_REF_CONDITIONAL defs. So if DF_LIVE doesn't exist, i.e.
5501 at -O1, just give up searching NEXT_BLOCK. */
5503 for (i
= dregno
; i
< end_dregno
; i
++)
5505 CLEAR_REGNO_REG_SET (live_out
, i
);
5506 CLEAR_REGNO_REG_SET (live_in
, i
);
5509 for (i
= sregno
; i
< end_sregno
; i
++)
5511 SET_REGNO_REG_SET (live_out
, i
);
5512 SET_REGNO_REG_SET (live_in
, i
);
5516 /* If we don't need to add the move to BB, look for a single
5519 next_block
= next_block_for_reg (next_block
, dregno
, end_dregno
);
5523 /* BB now defines DEST. It only uses the parts of DEST that overlap SRC
5525 for (i
= dregno
; i
< end_dregno
; i
++)
5527 CLEAR_REGNO_REG_SET (bb_uses
, i
);
5528 SET_REGNO_REG_SET (bb_defs
, i
);
5531 /* BB now uses SRC. */
5532 for (i
= sregno
; i
< end_sregno
; i
++)
5533 SET_REGNO_REG_SET (bb_uses
, i
);
5535 emit_insn_after (PATTERN (insn
), bb_note (bb
));
5540 /* Look for register copies in the first block of the function, and move
5541 them down into successor blocks if the register is used only on one
5542 path. This exposes more opportunities for shrink-wrapping. These
5543 kinds of sets often occur when incoming argument registers are moved
5544 to call-saved registers because their values are live across one or
5545 more calls during the function. */
5548 prepare_shrink_wrap (basic_block entry_block
)
5551 HARD_REG_SET uses
, defs
;
5554 CLEAR_HARD_REG_SET (uses
);
5555 CLEAR_HARD_REG_SET (defs
);
5556 FOR_BB_INSNS_REVERSE_SAFE (entry_block
, insn
, curr
)
5557 if (NONDEBUG_INSN_P (insn
)
5558 && !move_insn_for_shrink_wrap (entry_block
, insn
, uses
, defs
))
5560 /* Add all defined registers to DEFs. */
5561 for (ref
= DF_INSN_DEFS (insn
); *ref
; ref
++)
5563 x
= DF_REF_REG (*ref
);
5564 if (REG_P (x
) && HARD_REGISTER_P (x
))
5565 SET_HARD_REG_BIT (defs
, REGNO (x
));
5568 /* Add all used registers to USESs. */
5569 for (ref
= DF_INSN_USES (insn
); *ref
; ref
++)
5571 x
= DF_REF_REG (*ref
);
5572 if (REG_P (x
) && HARD_REGISTER_P (x
))
5573 SET_HARD_REG_BIT (uses
, REGNO (x
));
5581 /* Insert use of return register before the end of BB. */
5584 emit_use_return_register_into_block (basic_block bb
)
5588 use_return_register ();
5593 if (reg_mentioned_p (cc0_rtx
, PATTERN (insn
)))
5594 insn
= prev_cc0_setter (insn
);
5596 emit_insn_before (seq
, insn
);
5600 /* Create a return pattern, either simple_return or return, depending on
5604 gen_return_pattern (bool simple_p
)
5606 #ifdef HAVE_simple_return
5607 return simple_p
? gen_simple_return () : gen_return ();
5609 gcc_assert (!simple_p
);
5610 return gen_return ();
5614 /* Insert an appropriate return pattern at the end of block BB. This
5615 also means updating block_for_insn appropriately. SIMPLE_P is
5616 the same as in gen_return_pattern and passed to it. */
5619 emit_return_into_block (bool simple_p
, basic_block bb
)
5622 jump
= emit_jump_insn_after (gen_return_pattern (simple_p
), BB_END (bb
));
5623 pat
= PATTERN (jump
);
5624 if (GET_CODE (pat
) == PARALLEL
)
5625 pat
= XVECEXP (pat
, 0, 0);
5626 gcc_assert (ANY_RETURN_P (pat
));
5627 JUMP_LABEL (jump
) = pat
;
5631 /* Set JUMP_LABEL for a return insn. */
5634 set_return_jump_label (rtx returnjump
)
5636 rtx pat
= PATTERN (returnjump
);
5637 if (GET_CODE (pat
) == PARALLEL
)
5638 pat
= XVECEXP (pat
, 0, 0);
5639 if (ANY_RETURN_P (pat
))
5640 JUMP_LABEL (returnjump
) = pat
;
5642 JUMP_LABEL (returnjump
) = ret_rtx
;
5645 #ifdef HAVE_simple_return
5646 /* Create a copy of BB instructions and insert at BEFORE. Redirect
5647 preds of BB to COPY_BB if they don't appear in NEED_PROLOGUE. */
5649 dup_block_and_redirect (basic_block bb
, basic_block copy_bb
, rtx before
,
5650 bitmap_head
*need_prologue
)
5654 rtx insn
= BB_END (bb
);
5656 /* We know BB has a single successor, so there is no need to copy a
5657 simple jump at the end of BB. */
5658 if (simplejump_p (insn
))
5659 insn
= PREV_INSN (insn
);
5662 duplicate_insn_chain (BB_HEAD (bb
), insn
);
5666 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5667 if (active_insn_p (insn
))
5669 fprintf (dump_file
, "Duplicating bb %d to bb %d, %u active insns.\n",
5670 bb
->index
, copy_bb
->index
, count
);
5672 insn
= get_insns ();
5674 emit_insn_before (insn
, before
);
5676 /* Redirect all the paths that need no prologue into copy_bb. */
5677 for (ei
= ei_start (bb
->preds
); (e
= ei_safe_edge (ei
)); )
5678 if (!bitmap_bit_p (need_prologue
, e
->src
->index
))
5680 int freq
= EDGE_FREQUENCY (e
);
5681 copy_bb
->count
+= e
->count
;
5682 copy_bb
->frequency
+= EDGE_FREQUENCY (e
);
5683 e
->dest
->count
-= e
->count
;
5684 if (e
->dest
->count
< 0)
5686 e
->dest
->frequency
-= freq
;
5687 if (e
->dest
->frequency
< 0)
5688 e
->dest
->frequency
= 0;
5689 redirect_edge_and_branch_force (e
, copy_bb
);
5697 #if defined (HAVE_return) || defined (HAVE_simple_return)
5698 /* Return true if there are any active insns between HEAD and TAIL. */
5700 active_insn_between (rtx head
, rtx tail
)
5704 if (active_insn_p (tail
))
5708 tail
= PREV_INSN (tail
);
5713 /* LAST_BB is a block that exits, and empty of active instructions.
5714 Examine its predecessors for jumps that can be converted to
5715 (conditional) returns. */
5717 convert_jumps_to_returns (basic_block last_bb
, bool simple_p
,
5718 vec
<edge
> unconverted ATTRIBUTE_UNUSED
)
5725 auto_vec
<basic_block
> src_bbs (EDGE_COUNT (last_bb
->preds
));
5727 FOR_EACH_EDGE (e
, ei
, last_bb
->preds
)
5728 if (e
->src
!= ENTRY_BLOCK_PTR_FOR_FN (cfun
))
5729 src_bbs
.quick_push (e
->src
);
5731 label
= BB_HEAD (last_bb
);
5733 FOR_EACH_VEC_ELT (src_bbs
, i
, bb
)
5735 rtx jump
= BB_END (bb
);
5737 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5740 e
= find_edge (bb
, last_bb
);
5742 /* If we have an unconditional jump, we can replace that
5743 with a simple return instruction. */
5744 if (simplejump_p (jump
))
5746 /* The use of the return register might be present in the exit
5747 fallthru block. Either:
5748 - removing the use is safe, and we should remove the use in
5749 the exit fallthru block, or
5750 - removing the use is not safe, and we should add it here.
5751 For now, we conservatively choose the latter. Either of the
5752 2 helps in crossjumping. */
5753 emit_use_return_register_into_block (bb
);
5755 emit_return_into_block (simple_p
, bb
);
5759 /* If we have a conditional jump branching to the last
5760 block, we can try to replace that with a conditional
5761 return instruction. */
5762 else if (condjump_p (jump
))
5767 dest
= simple_return_rtx
;
5770 if (!redirect_jump (jump
, dest
, 0))
5772 #ifdef HAVE_simple_return
5777 "Failed to redirect bb %d branch.\n", bb
->index
);
5778 unconverted
.safe_push (e
);
5784 /* See comment in simplejump_p case above. */
5785 emit_use_return_register_into_block (bb
);
5787 /* If this block has only one successor, it both jumps
5788 and falls through to the fallthru block, so we can't
5790 if (single_succ_p (bb
))
5795 #ifdef HAVE_simple_return
5800 "Failed to redirect bb %d branch.\n", bb
->index
);
5801 unconverted
.safe_push (e
);
5807 /* Fix up the CFG for the successful change we just made. */
5808 redirect_edge_succ (e
, EXIT_BLOCK_PTR_FOR_FN (cfun
));
5809 e
->flags
&= ~EDGE_CROSSING
;
5815 /* Emit a return insn for the exit fallthru block. */
5817 emit_return_for_exit (edge exit_fallthru_edge
, bool simple_p
)
5819 basic_block last_bb
= exit_fallthru_edge
->src
;
5821 if (JUMP_P (BB_END (last_bb
)))
5823 last_bb
= split_edge (exit_fallthru_edge
);
5824 exit_fallthru_edge
= single_succ_edge (last_bb
);
5826 emit_barrier_after (BB_END (last_bb
));
5827 emit_return_into_block (simple_p
, last_bb
);
5828 exit_fallthru_edge
->flags
&= ~EDGE_FALLTHRU
;
5834 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5835 this into place with notes indicating where the prologue ends and where
5836 the epilogue begins. Update the basic block information when possible.
5838 Notes on epilogue placement:
5839 There are several kinds of edges to the exit block:
5840 * a single fallthru edge from LAST_BB
5841 * possibly, edges from blocks containing sibcalls
5842 * possibly, fake edges from infinite loops
5844 The epilogue is always emitted on the fallthru edge from the last basic
5845 block in the function, LAST_BB, into the exit block.
5847 If LAST_BB is empty except for a label, it is the target of every
5848 other basic block in the function that ends in a return. If a
5849 target has a return or simple_return pattern (possibly with
5850 conditional variants), these basic blocks can be changed so that a
5851 return insn is emitted into them, and their target is adjusted to
5852 the real exit block.
5854 Notes on shrink wrapping: We implement a fairly conservative
5855 version of shrink-wrapping rather than the textbook one. We only
5856 generate a single prologue and a single epilogue. This is
5857 sufficient to catch a number of interesting cases involving early
5860 First, we identify the blocks that require the prologue to occur before
5861 them. These are the ones that modify a call-saved register, or reference
5862 any of the stack or frame pointer registers. To simplify things, we then
5863 mark everything reachable from these blocks as also requiring a prologue.
5864 This takes care of loops automatically, and avoids the need to examine
5865 whether MEMs reference the frame, since it is sufficient to check for
5866 occurrences of the stack or frame pointer.
5868 We then compute the set of blocks for which the need for a prologue
5869 is anticipatable (borrowing terminology from the shrink-wrapping
5870 description in Muchnick's book). These are the blocks which either
5871 require a prologue themselves, or those that have only successors
5872 where the prologue is anticipatable. The prologue needs to be
5873 inserted on all edges from BB1->BB2 where BB2 is in ANTIC and BB1
5874 is not. For the moment, we ensure that only one such edge exists.
5876 The epilogue is placed as described above, but we make a
5877 distinction between inserting return and simple_return patterns
5878 when modifying other blocks that end in a return. Blocks that end
5879 in a sibcall omit the sibcall_epilogue if the block is not in
5883 thread_prologue_and_epilogue_insns (void)
5886 #ifdef HAVE_simple_return
5887 vec
<edge
> unconverted_simple_returns
= vNULL
;
5888 bool nonempty_prologue
;
5889 bitmap_head bb_flags
;
5890 unsigned max_grow_size
;
5893 rtx seq ATTRIBUTE_UNUSED
, epilogue_end ATTRIBUTE_UNUSED
;
5894 rtx prologue_seq ATTRIBUTE_UNUSED
, split_prologue_seq ATTRIBUTE_UNUSED
;
5895 edge e
, entry_edge
, orig_entry_edge
, exit_fallthru_edge
;
5900 rtl_profile_for_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
5904 epilogue_end
= NULL_RTX
;
5905 returnjump
= NULL_RTX
;
5907 /* Can't deal with multiple successors of the entry block at the
5908 moment. Function should always have at least one entry
5910 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR_FOR_FN (cfun
)));
5911 entry_edge
= single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun
));
5912 orig_entry_edge
= entry_edge
;
5914 split_prologue_seq
= NULL_RTX
;
5915 if (flag_split_stack
5916 && (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun
->decl
))
5919 #ifndef HAVE_split_stack_prologue
5922 gcc_assert (HAVE_split_stack_prologue
);
5925 emit_insn (gen_split_stack_prologue ());
5926 split_prologue_seq
= get_insns ();
5929 record_insns (split_prologue_seq
, NULL
, &prologue_insn_hash
);
5930 set_insn_locations (split_prologue_seq
, prologue_location
);
5934 prologue_seq
= NULL_RTX
;
5935 #ifdef HAVE_prologue
5939 seq
= gen_prologue ();
5942 /* Insert an explicit USE for the frame pointer
5943 if the profiling is on and the frame pointer is required. */
5944 if (crtl
->profile
&& frame_pointer_needed
)
5945 emit_use (hard_frame_pointer_rtx
);
5947 /* Retain a map of the prologue insns. */
5948 record_insns (seq
, NULL
, &prologue_insn_hash
);
5949 emit_note (NOTE_INSN_PROLOGUE_END
);
5951 /* Ensure that instructions are not moved into the prologue when
5952 profiling is on. The call to the profiling routine can be
5953 emitted within the live range of a call-clobbered register. */
5954 if (!targetm
.profile_before_prologue () && crtl
->profile
)
5955 emit_insn (gen_blockage ());
5957 prologue_seq
= get_insns ();
5959 set_insn_locations (prologue_seq
, prologue_location
);
5963 #ifdef HAVE_simple_return
5964 bitmap_initialize (&bb_flags
, &bitmap_default_obstack
);
5966 /* Try to perform a kind of shrink-wrapping, making sure the
5967 prologue/epilogue is emitted only around those parts of the
5968 function that require it. */
5970 nonempty_prologue
= false;
5971 for (seq
= prologue_seq
; seq
; seq
= NEXT_INSN (seq
))
5972 if (!NOTE_P (seq
) || NOTE_KIND (seq
) != NOTE_INSN_PROLOGUE_END
)
5974 nonempty_prologue
= true;
5978 if (flag_shrink_wrap
&& HAVE_simple_return
5979 && (targetm
.profile_before_prologue () || !crtl
->profile
)
5980 && nonempty_prologue
&& !crtl
->calls_eh_return
)
5982 HARD_REG_SET prologue_clobbered
, prologue_used
, live_on_edge
;
5983 struct hard_reg_set_container set_up_by_prologue
;
5985 vec
<basic_block
> vec
;
5987 bitmap_head bb_antic_flags
;
5988 bitmap_head bb_on_list
;
5989 bitmap_head bb_tail
;
5992 fprintf (dump_file
, "Attempting shrink-wrapping optimization.\n");
5994 /* Compute the registers set and used in the prologue. */
5995 CLEAR_HARD_REG_SET (prologue_clobbered
);
5996 CLEAR_HARD_REG_SET (prologue_used
);
5997 for (p_insn
= prologue_seq
; p_insn
; p_insn
= NEXT_INSN (p_insn
))
5999 HARD_REG_SET this_used
;
6000 if (!NONDEBUG_INSN_P (p_insn
))
6003 CLEAR_HARD_REG_SET (this_used
);
6004 note_uses (&PATTERN (p_insn
), record_hard_reg_uses
,
6006 AND_COMPL_HARD_REG_SET (this_used
, prologue_clobbered
);
6007 IOR_HARD_REG_SET (prologue_used
, this_used
);
6008 note_stores (PATTERN (p_insn
), record_hard_reg_sets
,
6009 &prologue_clobbered
);
6012 prepare_shrink_wrap (entry_edge
->dest
);
6014 bitmap_initialize (&bb_antic_flags
, &bitmap_default_obstack
);
6015 bitmap_initialize (&bb_on_list
, &bitmap_default_obstack
);
6016 bitmap_initialize (&bb_tail
, &bitmap_default_obstack
);
6018 /* Find the set of basic blocks that require a stack frame,
6019 and blocks that are too big to be duplicated. */
6021 vec
.create (n_basic_blocks_for_fn (cfun
));
6023 CLEAR_HARD_REG_SET (set_up_by_prologue
.set
);
6024 add_to_hard_reg_set (&set_up_by_prologue
.set
, Pmode
,
6025 STACK_POINTER_REGNUM
);
6026 add_to_hard_reg_set (&set_up_by_prologue
.set
, Pmode
, ARG_POINTER_REGNUM
);
6027 if (frame_pointer_needed
)
6028 add_to_hard_reg_set (&set_up_by_prologue
.set
, Pmode
,
6029 HARD_FRAME_POINTER_REGNUM
);
6030 if (pic_offset_table_rtx
)
6031 add_to_hard_reg_set (&set_up_by_prologue
.set
, Pmode
,
6032 PIC_OFFSET_TABLE_REGNUM
);
6034 add_to_hard_reg_set (&set_up_by_prologue
.set
,
6035 GET_MODE (crtl
->drap_reg
),
6036 REGNO (crtl
->drap_reg
));
6037 if (targetm
.set_up_by_prologue
)
6038 targetm
.set_up_by_prologue (&set_up_by_prologue
);
6040 /* We don't use a different max size depending on
6041 optimize_bb_for_speed_p because increasing shrink-wrapping
6042 opportunities by duplicating tail blocks can actually result
6043 in an overall decrease in code size. */
6044 max_grow_size
= get_uncond_jump_length ();
6045 max_grow_size
*= PARAM_VALUE (PARAM_MAX_GROW_COPY_BB_INSNS
);
6047 FOR_EACH_BB_FN (bb
, cfun
)
6052 FOR_BB_INSNS (bb
, insn
)
6053 if (NONDEBUG_INSN_P (insn
))
6055 if (requires_stack_frame_p (insn
, prologue_used
,
6056 set_up_by_prologue
.set
))
6058 if (bb
== entry_edge
->dest
)
6059 goto fail_shrinkwrap
;
6060 bitmap_set_bit (&bb_flags
, bb
->index
);
6061 vec
.quick_push (bb
);
6064 else if (size
<= max_grow_size
)
6066 size
+= get_attr_min_length (insn
);
6067 if (size
> max_grow_size
)
6068 bitmap_set_bit (&bb_on_list
, bb
->index
);
6073 /* Blocks that really need a prologue, or are too big for tails. */
6074 bitmap_ior_into (&bb_on_list
, &bb_flags
);
6076 /* For every basic block that needs a prologue, mark all blocks
6077 reachable from it, so as to ensure they are also seen as
6078 requiring a prologue. */
6079 while (!vec
.is_empty ())
6081 basic_block tmp_bb
= vec
.pop ();
6083 FOR_EACH_EDGE (e
, ei
, tmp_bb
->succs
)
6084 if (e
->dest
!= EXIT_BLOCK_PTR_FOR_FN (cfun
)
6085 && bitmap_set_bit (&bb_flags
, e
->dest
->index
))
6086 vec
.quick_push (e
->dest
);
6089 /* Find the set of basic blocks that need no prologue, have a
6090 single successor, can be duplicated, meet a max size
6091 requirement, and go to the exit via like blocks. */
6092 vec
.quick_push (EXIT_BLOCK_PTR_FOR_FN (cfun
));
6093 while (!vec
.is_empty ())
6095 basic_block tmp_bb
= vec
.pop ();
6097 FOR_EACH_EDGE (e
, ei
, tmp_bb
->preds
)
6098 if (single_succ_p (e
->src
)
6099 && !bitmap_bit_p (&bb_on_list
, e
->src
->index
)
6100 && can_duplicate_block_p (e
->src
))
6105 /* If there is predecessor of e->src which doesn't
6106 need prologue and the edge is complex,
6107 we might not be able to redirect the branch
6108 to a copy of e->src. */
6109 FOR_EACH_EDGE (pe
, pei
, e
->src
->preds
)
6110 if ((pe
->flags
& EDGE_COMPLEX
) != 0
6111 && !bitmap_bit_p (&bb_flags
, pe
->src
->index
))
6113 if (pe
== NULL
&& bitmap_set_bit (&bb_tail
, e
->src
->index
))
6114 vec
.quick_push (e
->src
);
6118 /* Now walk backwards from every block that is marked as needing
6119 a prologue to compute the bb_antic_flags bitmap. Exclude
6120 tail blocks; They can be duplicated to be used on paths not
6121 needing a prologue. */
6122 bitmap_clear (&bb_on_list
);
6123 bitmap_and_compl (&bb_antic_flags
, &bb_flags
, &bb_tail
);
6124 FOR_EACH_BB_FN (bb
, cfun
)
6126 if (!bitmap_bit_p (&bb_antic_flags
, bb
->index
))
6128 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6129 if (!bitmap_bit_p (&bb_antic_flags
, e
->src
->index
)
6130 && bitmap_set_bit (&bb_on_list
, e
->src
->index
))
6131 vec
.quick_push (e
->src
);
6133 while (!vec
.is_empty ())
6135 basic_block tmp_bb
= vec
.pop ();
6136 bool all_set
= true;
6138 bitmap_clear_bit (&bb_on_list
, tmp_bb
->index
);
6139 FOR_EACH_EDGE (e
, ei
, tmp_bb
->succs
)
6140 if (!bitmap_bit_p (&bb_antic_flags
, e
->dest
->index
))
6148 bitmap_set_bit (&bb_antic_flags
, tmp_bb
->index
);
6149 FOR_EACH_EDGE (e
, ei
, tmp_bb
->preds
)
6150 if (!bitmap_bit_p (&bb_antic_flags
, e
->src
->index
)
6151 && bitmap_set_bit (&bb_on_list
, e
->src
->index
))
6152 vec
.quick_push (e
->src
);
6155 /* Find exactly one edge that leads to a block in ANTIC from
6156 a block that isn't. */
6157 if (!bitmap_bit_p (&bb_antic_flags
, entry_edge
->dest
->index
))
6158 FOR_EACH_BB_FN (bb
, cfun
)
6160 if (!bitmap_bit_p (&bb_antic_flags
, bb
->index
))
6162 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6163 if (!bitmap_bit_p (&bb_antic_flags
, e
->src
->index
))
6165 if (entry_edge
!= orig_entry_edge
)
6167 entry_edge
= orig_entry_edge
;
6169 fprintf (dump_file
, "More than one candidate edge.\n");
6170 goto fail_shrinkwrap
;
6173 fprintf (dump_file
, "Found candidate edge for "
6174 "shrink-wrapping, %d->%d.\n", e
->src
->index
,
6180 if (entry_edge
!= orig_entry_edge
)
6182 /* Test whether the prologue is known to clobber any register
6183 (other than FP or SP) which are live on the edge. */
6184 CLEAR_HARD_REG_BIT (prologue_clobbered
, STACK_POINTER_REGNUM
);
6185 if (frame_pointer_needed
)
6186 CLEAR_HARD_REG_BIT (prologue_clobbered
, HARD_FRAME_POINTER_REGNUM
);
6187 REG_SET_TO_HARD_REG_SET (live_on_edge
,
6188 df_get_live_in (entry_edge
->dest
));
6189 if (hard_reg_set_intersect_p (live_on_edge
, prologue_clobbered
))
6191 entry_edge
= orig_entry_edge
;
6194 "Shrink-wrapping aborted due to clobber.\n");
6197 if (entry_edge
!= orig_entry_edge
)
6199 crtl
->shrink_wrapped
= true;
6201 fprintf (dump_file
, "Performing shrink-wrapping.\n");
6203 /* Find tail blocks reachable from both blocks needing a
6204 prologue and blocks not needing a prologue. */
6205 if (!bitmap_empty_p (&bb_tail
))
6206 FOR_EACH_BB_FN (bb
, cfun
)
6208 bool some_pro
, some_no_pro
;
6209 if (!bitmap_bit_p (&bb_tail
, bb
->index
))
6211 some_pro
= some_no_pro
= false;
6212 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6214 if (bitmap_bit_p (&bb_flags
, e
->src
->index
))
6219 if (some_pro
&& some_no_pro
)
6220 vec
.quick_push (bb
);
6222 bitmap_clear_bit (&bb_tail
, bb
->index
);
6224 /* Find the head of each tail. */
6225 while (!vec
.is_empty ())
6227 basic_block tbb
= vec
.pop ();
6229 if (!bitmap_bit_p (&bb_tail
, tbb
->index
))
6232 while (single_succ_p (tbb
))
6234 tbb
= single_succ (tbb
);
6235 bitmap_clear_bit (&bb_tail
, tbb
->index
);
6238 /* Now duplicate the tails. */
6239 if (!bitmap_empty_p (&bb_tail
))
6240 FOR_EACH_BB_REVERSE_FN (bb
, cfun
)
6242 basic_block copy_bb
, tbb
;
6246 if (!bitmap_clear_bit (&bb_tail
, bb
->index
))
6249 /* Create a copy of BB, instructions and all, for
6250 use on paths that don't need a prologue.
6251 Ideal placement of the copy is on a fall-thru edge
6252 or after a block that would jump to the copy. */
6253 FOR_EACH_EDGE (e
, ei
, bb
->preds
)
6254 if (!bitmap_bit_p (&bb_flags
, e
->src
->index
)
6255 && single_succ_p (e
->src
))
6259 /* Make sure we insert after any barriers. */
6260 rtx end
= get_last_bb_insn (e
->src
);
6261 copy_bb
= create_basic_block (NEXT_INSN (end
),
6263 BB_COPY_PARTITION (copy_bb
, e
->src
);
6267 /* Otherwise put the copy at the end of the function. */
6268 copy_bb
= create_basic_block (NULL_RTX
, NULL_RTX
,
6269 EXIT_BLOCK_PTR_FOR_FN (cfun
)->prev_bb
);
6270 BB_COPY_PARTITION (copy_bb
, bb
);
6273 insert_point
= emit_note_after (NOTE_INSN_DELETED
,
6275 emit_barrier_after (BB_END (copy_bb
));
6280 dup_block_and_redirect (tbb
, copy_bb
, insert_point
,
6282 tbb
= single_succ (tbb
);
6283 if (tbb
== EXIT_BLOCK_PTR_FOR_FN (cfun
))
6285 e
= split_block (copy_bb
, PREV_INSN (insert_point
));
6289 /* Quiet verify_flow_info by (ab)using EDGE_FAKE.
6290 We have yet to add a simple_return to the tails,
6291 as we'd like to first convert_jumps_to_returns in
6292 case the block is no longer used after that. */
6294 if (CALL_P (PREV_INSN (insert_point
))
6295 && SIBLING_CALL_P (PREV_INSN (insert_point
)))
6296 eflags
= EDGE_SIBCALL
| EDGE_ABNORMAL
;
6297 make_single_succ_edge (copy_bb
, EXIT_BLOCK_PTR_FOR_FN (cfun
),
6300 /* verify_flow_info doesn't like a note after a
6302 delete_insn (insert_point
);
6303 if (bitmap_empty_p (&bb_tail
))
6309 bitmap_clear (&bb_tail
);
6310 bitmap_clear (&bb_antic_flags
);
6311 bitmap_clear (&bb_on_list
);
6316 if (split_prologue_seq
!= NULL_RTX
)
6318 insert_insn_on_edge (split_prologue_seq
, orig_entry_edge
);
6321 if (prologue_seq
!= NULL_RTX
)
6323 insert_insn_on_edge (prologue_seq
, entry_edge
);
6327 /* If the exit block has no non-fake predecessors, we don't need
6329 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6330 if ((e
->flags
& EDGE_FAKE
) == 0)
6335 rtl_profile_for_bb (EXIT_BLOCK_PTR_FOR_FN (cfun
));
6337 exit_fallthru_edge
= find_fallthru_edge (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6339 /* If we're allowed to generate a simple return instruction, then by
6340 definition we don't need a full epilogue. If the last basic
6341 block before the exit block does not contain active instructions,
6342 examine its predecessors and try to emit (conditional) return
6344 #ifdef HAVE_simple_return
6345 if (entry_edge
!= orig_entry_edge
)
6351 /* convert_jumps_to_returns may add to preds of the exit block
6352 (but won't remove). Stop at end of current preds. */
6353 last
= EDGE_COUNT (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
);
6354 for (i
= 0; i
< last
; i
++)
6356 e
= EDGE_I (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
, i
);
6357 if (LABEL_P (BB_HEAD (e
->src
))
6358 && !bitmap_bit_p (&bb_flags
, e
->src
->index
)
6359 && !active_insn_between (BB_HEAD (e
->src
), BB_END (e
->src
)))
6360 unconverted_simple_returns
6361 = convert_jumps_to_returns (e
->src
, true,
6362 unconverted_simple_returns
);
6366 if (exit_fallthru_edge
!= NULL
6367 && EDGE_COUNT (exit_fallthru_edge
->src
->preds
) != 0
6368 && !bitmap_bit_p (&bb_flags
, exit_fallthru_edge
->src
->index
))
6370 basic_block last_bb
;
6372 last_bb
= emit_return_for_exit (exit_fallthru_edge
, true);
6373 returnjump
= BB_END (last_bb
);
6374 exit_fallthru_edge
= NULL
;
6381 if (exit_fallthru_edge
== NULL
)
6386 basic_block last_bb
= exit_fallthru_edge
->src
;
6388 if (LABEL_P (BB_HEAD (last_bb
))
6389 && !active_insn_between (BB_HEAD (last_bb
), BB_END (last_bb
)))
6390 convert_jumps_to_returns (last_bb
, false, vNULL
);
6392 if (EDGE_COUNT (last_bb
->preds
) != 0
6393 && single_succ_p (last_bb
))
6395 last_bb
= emit_return_for_exit (exit_fallthru_edge
, false);
6396 epilogue_end
= returnjump
= BB_END (last_bb
);
6397 #ifdef HAVE_simple_return
6398 /* Emitting the return may add a basic block.
6399 Fix bb_flags for the added block. */
6400 if (last_bb
!= exit_fallthru_edge
->src
)
6401 bitmap_set_bit (&bb_flags
, last_bb
->index
);
6409 /* A small fib -- epilogue is not yet completed, but we wish to re-use
6410 this marker for the splits of EH_RETURN patterns, and nothing else
6411 uses the flag in the meantime. */
6412 epilogue_completed
= 1;
6414 #ifdef HAVE_eh_return
6415 /* Find non-fallthru edges that end with EH_RETURN instructions. On
6416 some targets, these get split to a special version of the epilogue
6417 code. In order to be able to properly annotate these with unwind
6418 info, try to split them now. If we get a valid split, drop an
6419 EPILOGUE_BEG note and mark the insns as epilogue insns. */
6420 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6422 rtx prev
, last
, trial
;
6424 if (e
->flags
& EDGE_FALLTHRU
)
6426 last
= BB_END (e
->src
);
6427 if (!eh_returnjump_p (last
))
6430 prev
= PREV_INSN (last
);
6431 trial
= try_split (PATTERN (last
), last
, 1);
6435 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
6436 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
6440 /* If nothing falls through into the exit block, we don't need an
6443 if (exit_fallthru_edge
== NULL
)
6446 #ifdef HAVE_epilogue
6450 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
6451 seq
= gen_epilogue ();
6453 emit_jump_insn (seq
);
6455 /* Retain a map of the epilogue insns. */
6456 record_insns (seq
, NULL
, &epilogue_insn_hash
);
6457 set_insn_locations (seq
, epilogue_location
);
6460 returnjump
= get_last_insn ();
6463 insert_insn_on_edge (seq
, exit_fallthru_edge
);
6466 if (JUMP_P (returnjump
))
6467 set_return_jump_label (returnjump
);
6474 if (! next_active_insn (BB_END (exit_fallthru_edge
->src
)))
6476 /* We have a fall-through edge to the exit block, the source is not
6477 at the end of the function, and there will be an assembler epilogue
6478 at the end of the function.
6479 We can't use force_nonfallthru here, because that would try to
6480 use return. Inserting a jump 'by hand' is extremely messy, so
6481 we take advantage of cfg_layout_finalize using
6482 fixup_fallthru_exit_predecessor. */
6483 cfg_layout_initialize (0);
6484 FOR_EACH_BB_FN (cur_bb
, cfun
)
6485 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
6486 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
6487 cur_bb
->aux
= cur_bb
->next_bb
;
6488 cfg_layout_finalize ();
6493 default_rtl_profile ();
6499 commit_edge_insertions ();
6501 /* Look for basic blocks within the prologue insns. */
6502 blocks
= sbitmap_alloc (last_basic_block_for_fn (cfun
));
6503 bitmap_clear (blocks
);
6504 bitmap_set_bit (blocks
, entry_edge
->dest
->index
);
6505 bitmap_set_bit (blocks
, orig_entry_edge
->dest
->index
);
6506 find_many_sub_basic_blocks (blocks
);
6507 sbitmap_free (blocks
);
6509 /* The epilogue insns we inserted may cause the exit edge to no longer
6511 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6513 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
6514 && returnjump_p (BB_END (e
->src
)))
6515 e
->flags
&= ~EDGE_FALLTHRU
;
6519 #ifdef HAVE_simple_return
6520 /* If there were branches to an empty LAST_BB which we tried to
6521 convert to conditional simple_returns, but couldn't for some
6522 reason, create a block to hold a simple_return insn and redirect
6523 those remaining edges. */
6524 if (!unconverted_simple_returns
.is_empty ())
6526 basic_block simple_return_block_hot
= NULL
;
6527 basic_block simple_return_block_cold
= NULL
;
6528 edge pending_edge_hot
= NULL
;
6529 edge pending_edge_cold
= NULL
;
6530 basic_block exit_pred
;
6533 gcc_assert (entry_edge
!= orig_entry_edge
);
6535 /* See if we can reuse the last insn that was emitted for the
6537 if (returnjump
!= NULL_RTX
6538 && JUMP_LABEL (returnjump
) == simple_return_rtx
)
6540 e
= split_block (BLOCK_FOR_INSN (returnjump
), PREV_INSN (returnjump
));
6541 if (BB_PARTITION (e
->src
) == BB_HOT_PARTITION
)
6542 simple_return_block_hot
= e
->dest
;
6544 simple_return_block_cold
= e
->dest
;
6547 /* Also check returns we might need to add to tail blocks. */
6548 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6549 if (EDGE_COUNT (e
->src
->preds
) != 0
6550 && (e
->flags
& EDGE_FAKE
) != 0
6551 && !bitmap_bit_p (&bb_flags
, e
->src
->index
))
6553 if (BB_PARTITION (e
->src
) == BB_HOT_PARTITION
)
6554 pending_edge_hot
= e
;
6556 pending_edge_cold
= e
;
6559 /* Save a pointer to the exit's predecessor BB for use in
6560 inserting new BBs at the end of the function. Do this
6561 after the call to split_block above which may split
6562 the original exit pred. */
6563 exit_pred
= EXIT_BLOCK_PTR_FOR_FN (cfun
)->prev_bb
;
6565 FOR_EACH_VEC_ELT (unconverted_simple_returns
, i
, e
)
6567 basic_block
*pdest_bb
;
6570 if (BB_PARTITION (e
->src
) == BB_HOT_PARTITION
)
6572 pdest_bb
= &simple_return_block_hot
;
6573 pending
= pending_edge_hot
;
6577 pdest_bb
= &simple_return_block_cold
;
6578 pending
= pending_edge_cold
;
6581 if (*pdest_bb
== NULL
&& pending
!= NULL
)
6583 emit_return_into_block (true, pending
->src
);
6584 pending
->flags
&= ~(EDGE_FALLTHRU
| EDGE_FAKE
);
6585 *pdest_bb
= pending
->src
;
6587 else if (*pdest_bb
== NULL
)
6592 bb
= create_basic_block (NULL
, NULL
, exit_pred
);
6593 BB_COPY_PARTITION (bb
, e
->src
);
6594 start
= emit_jump_insn_after (gen_simple_return (),
6596 JUMP_LABEL (start
) = simple_return_rtx
;
6597 emit_barrier_after (start
);
6600 make_edge (bb
, EXIT_BLOCK_PTR_FOR_FN (cfun
), 0);
6602 redirect_edge_and_branch_force (e
, *pdest_bb
);
6604 unconverted_simple_returns
.release ();
6607 if (entry_edge
!= orig_entry_edge
)
6609 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6610 if (EDGE_COUNT (e
->src
->preds
) != 0
6611 && (e
->flags
& EDGE_FAKE
) != 0
6612 && !bitmap_bit_p (&bb_flags
, e
->src
->index
))
6614 emit_return_into_block (true, e
->src
);
6615 e
->flags
&= ~(EDGE_FALLTHRU
| EDGE_FAKE
);
6620 #ifdef HAVE_sibcall_epilogue
6621 /* Emit sibling epilogues before any sibling call sites. */
6622 for (ei
= ei_start (EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
); (e
=
6626 basic_block bb
= e
->src
;
6627 rtx insn
= BB_END (bb
);
6631 || ! SIBLING_CALL_P (insn
)
6632 #ifdef HAVE_simple_return
6633 || (entry_edge
!= orig_entry_edge
6634 && !bitmap_bit_p (&bb_flags
, bb
->index
))
6642 ep_seq
= gen_sibcall_epilogue ();
6646 emit_note (NOTE_INSN_EPILOGUE_BEG
);
6651 /* Retain a map of the epilogue insns. Used in life analysis to
6652 avoid getting rid of sibcall epilogue insns. Do this before we
6653 actually emit the sequence. */
6654 record_insns (seq
, NULL
, &epilogue_insn_hash
);
6655 set_insn_locations (seq
, epilogue_location
);
6657 emit_insn_before (seq
, insn
);
6663 #ifdef HAVE_epilogue
6668 /* Similarly, move any line notes that appear after the epilogue.
6669 There is no need, however, to be quite so anal about the existence
6670 of such a note. Also possibly move
6671 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
6673 for (insn
= epilogue_end
; insn
; insn
= next
)
6675 next
= NEXT_INSN (insn
);
6677 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
6678 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
6683 #ifdef HAVE_simple_return
6684 bitmap_clear (&bb_flags
);
6687 /* Threading the prologue and epilogue changes the artificial refs
6688 in the entry and exit blocks. */
6689 epilogue_completed
= 1;
6690 df_update_entry_exit_and_calls ();
6693 /* Reposition the prologue-end and epilogue-begin notes after
6694 instruction scheduling. */
6697 reposition_prologue_and_epilogue_notes (void)
6699 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
6700 || defined (HAVE_sibcall_epilogue)
6701 /* Since the hash table is created on demand, the fact that it is
6702 non-null is a signal that it is non-empty. */
6703 if (prologue_insn_hash
!= NULL
)
6705 size_t len
= htab_elements (prologue_insn_hash
);
6706 rtx insn
, last
= NULL
, note
= NULL
;
6708 /* Scan from the beginning until we reach the last prologue insn. */
6709 /* ??? While we do have the CFG intact, there are two problems:
6710 (1) The prologue can contain loops (typically probing the stack),
6711 which means that the end of the prologue isn't in the first bb.
6712 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
6713 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
6717 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
6720 else if (contains (insn
, prologue_insn_hash
))
6732 /* Scan forward looking for the PROLOGUE_END note. It should
6733 be right at the beginning of the block, possibly with other
6734 insn notes that got moved there. */
6735 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
6738 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
6743 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
6745 last
= NEXT_INSN (last
);
6746 reorder_insns (note
, note
, last
);
6750 if (epilogue_insn_hash
!= NULL
)
6755 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR_FOR_FN (cfun
)->preds
)
6757 rtx insn
, first
= NULL
, note
= NULL
;
6758 basic_block bb
= e
->src
;
6760 /* Scan from the beginning until we reach the first epilogue insn. */
6761 FOR_BB_INSNS (bb
, insn
)
6765 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
6772 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
6782 /* If the function has a single basic block, and no real
6783 epilogue insns (e.g. sibcall with no cleanup), the
6784 epilogue note can get scheduled before the prologue
6785 note. If we have frame related prologue insns, having
6786 them scanned during the epilogue will result in a crash.
6787 In this case re-order the epilogue note to just before
6788 the last insn in the block. */
6790 first
= BB_END (bb
);
6792 if (PREV_INSN (first
) != note
)
6793 reorder_insns (note
, note
, PREV_INSN (first
));
6797 #endif /* HAVE_prologue or HAVE_epilogue */
6800 /* Returns the name of function declared by FNDECL. */
6802 fndecl_name (tree fndecl
)
6806 return lang_hooks
.decl_printable_name (fndecl
, 2);
6809 /* Returns the name of function FN. */
6811 function_name (struct function
*fn
)
6813 tree fndecl
= (fn
== NULL
) ? NULL
: fn
->decl
;
6814 return fndecl_name (fndecl
);
6817 /* Returns the name of the current function. */
6819 current_function_name (void)
6821 return function_name (cfun
);
6826 rest_of_handle_check_leaf_regs (void)
6828 #ifdef LEAF_REGISTERS
6829 crtl
->uses_only_leaf_regs
6830 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
6835 /* Insert a TYPE into the used types hash table of CFUN. */
6838 used_types_insert_helper (tree type
, struct function
*func
)
6840 if (type
!= NULL
&& func
!= NULL
)
6844 if (func
->used_types_hash
== NULL
)
6845 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
6846 htab_eq_pointer
, NULL
);
6847 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
6853 /* Given a type, insert it into the used hash table in cfun. */
6855 used_types_insert (tree t
)
6857 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
6862 if (TREE_CODE (t
) == ERROR_MARK
)
6864 if (TYPE_NAME (t
) == NULL_TREE
6865 || TYPE_NAME (t
) == TYPE_NAME (TYPE_MAIN_VARIANT (t
)))
6866 t
= TYPE_MAIN_VARIANT (t
);
6867 if (debug_info_level
> DINFO_LEVEL_NONE
)
6870 used_types_insert_helper (t
, cfun
);
6873 /* So this might be a type referenced by a global variable.
6874 Record that type so that we can later decide to emit its
6875 debug information. */
6876 vec_safe_push (types_used_by_cur_var_decl
, t
);
6881 /* Helper to Hash a struct types_used_by_vars_entry. */
6884 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
6886 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
6888 return iterative_hash_object (entry
->type
,
6889 iterative_hash_object (entry
->var_decl
, 0));
6892 /* Hash function of the types_used_by_vars_entry hash table. */
6895 types_used_by_vars_do_hash (const void *x
)
6897 const struct types_used_by_vars_entry
*entry
=
6898 (const struct types_used_by_vars_entry
*) x
;
6900 return hash_types_used_by_vars_entry (entry
);
6903 /*Equality function of the types_used_by_vars_entry hash table. */
6906 types_used_by_vars_eq (const void *x1
, const void *x2
)
6908 const struct types_used_by_vars_entry
*e1
=
6909 (const struct types_used_by_vars_entry
*) x1
;
6910 const struct types_used_by_vars_entry
*e2
=
6911 (const struct types_used_by_vars_entry
*)x2
;
6913 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
6916 /* Inserts an entry into the types_used_by_vars_hash hash table. */
6919 types_used_by_var_decl_insert (tree type
, tree var_decl
)
6921 if (type
!= NULL
&& var_decl
!= NULL
)
6924 struct types_used_by_vars_entry e
;
6925 e
.var_decl
= var_decl
;
6927 if (types_used_by_vars_hash
== NULL
)
6928 types_used_by_vars_hash
=
6929 htab_create_ggc (37, types_used_by_vars_do_hash
,
6930 types_used_by_vars_eq
, NULL
);
6931 slot
= htab_find_slot_with_hash (types_used_by_vars_hash
, &e
,
6932 hash_types_used_by_vars_entry (&e
), INSERT
);
6935 struct types_used_by_vars_entry
*entry
;
6936 entry
= ggc_alloc_types_used_by_vars_entry ();
6938 entry
->var_decl
= var_decl
;
6946 const pass_data pass_data_leaf_regs
=
6948 RTL_PASS
, /* type */
6949 "*leaf_regs", /* name */
6950 OPTGROUP_NONE
, /* optinfo_flags */
6951 true, /* has_execute */
6952 TV_NONE
, /* tv_id */
6953 0, /* properties_required */
6954 0, /* properties_provided */
6955 0, /* properties_destroyed */
6956 0, /* todo_flags_start */
6957 0, /* todo_flags_finish */
6960 class pass_leaf_regs
: public rtl_opt_pass
6963 pass_leaf_regs (gcc::context
*ctxt
)
6964 : rtl_opt_pass (pass_data_leaf_regs
, ctxt
)
6967 /* opt_pass methods: */
6968 unsigned int execute () { return rest_of_handle_check_leaf_regs (); }
6970 }; // class pass_leaf_regs
6975 make_pass_leaf_regs (gcc::context
*ctxt
)
6977 return new pass_leaf_regs (ctxt
);
6981 rest_of_handle_thread_prologue_and_epilogue (void)
6984 cleanup_cfg (CLEANUP_EXPENSIVE
);
6986 /* On some machines, the prologue and epilogue code, or parts thereof,
6987 can be represented as RTL. Doing so lets us schedule insns between
6988 it and the rest of the code and also allows delayed branch
6989 scheduling to operate in the epilogue. */
6990 thread_prologue_and_epilogue_insns ();
6992 /* Shrink-wrapping can result in unreachable edges in the epilogue,
6996 /* The stack usage info is finalized during prologue expansion. */
6997 if (flag_stack_usage_info
)
6998 output_stack_usage ();
7005 const pass_data pass_data_thread_prologue_and_epilogue
=
7007 RTL_PASS
, /* type */
7008 "pro_and_epilogue", /* name */
7009 OPTGROUP_NONE
, /* optinfo_flags */
7010 true, /* has_execute */
7011 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
7012 0, /* properties_required */
7013 0, /* properties_provided */
7014 0, /* properties_destroyed */
7015 TODO_verify_flow
, /* todo_flags_start */
7016 ( TODO_df_verify
| TODO_df_finish
7017 | TODO_verify_rtl_sharing
), /* todo_flags_finish */
7020 class pass_thread_prologue_and_epilogue
: public rtl_opt_pass
7023 pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
7024 : rtl_opt_pass (pass_data_thread_prologue_and_epilogue
, ctxt
)
7027 /* opt_pass methods: */
7028 unsigned int execute () {
7029 return rest_of_handle_thread_prologue_and_epilogue ();
7032 }; // class pass_thread_prologue_and_epilogue
7037 make_pass_thread_prologue_and_epilogue (gcc::context
*ctxt
)
7039 return new pass_thread_prologue_and_epilogue (ctxt
);
7043 /* This mini-pass fixes fall-out from SSA in asm statements that have
7044 in-out constraints. Say you start with
7047 asm ("": "+mr" (inout));
7050 which is transformed very early to use explicit output and match operands:
7053 asm ("": "=mr" (inout) : "0" (inout));
7056 Or, after SSA and copyprop,
7058 asm ("": "=mr" (inout_2) : "0" (inout_1));
7061 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
7062 they represent two separate values, so they will get different pseudo
7063 registers during expansion. Then, since the two operands need to match
7064 per the constraints, but use different pseudo registers, reload can
7065 only register a reload for these operands. But reloads can only be
7066 satisfied by hardregs, not by memory, so we need a register for this
7067 reload, just because we are presented with non-matching operands.
7068 So, even though we allow memory for this operand, no memory can be
7069 used for it, just because the two operands don't match. This can
7070 cause reload failures on register-starved targets.
7072 So it's a symptom of reload not being able to use memory for reloads
7073 or, alternatively it's also a symptom of both operands not coming into
7074 reload as matching (in which case the pseudo could go to memory just
7075 fine, as the alternative allows it, and no reload would be necessary).
7076 We fix the latter problem here, by transforming
7078 asm ("": "=mr" (inout_2) : "0" (inout_1));
7083 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
7086 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
7089 bool changed
= false;
7090 rtx op
= SET_SRC (p_sets
[0]);
7091 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
7092 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
7093 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
7095 memset (output_matched
, 0, noutputs
* sizeof (bool));
7096 for (i
= 0; i
< ninputs
; i
++)
7098 rtx input
, output
, insns
;
7099 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
7103 if (*constraint
== '%')
7106 match
= strtoul (constraint
, &end
, 10);
7107 if (end
== constraint
)
7110 gcc_assert (match
< noutputs
);
7111 output
= SET_DEST (p_sets
[match
]);
7112 input
= RTVEC_ELT (inputs
, i
);
7113 /* Only do the transformation for pseudos. */
7114 if (! REG_P (output
)
7115 || rtx_equal_p (output
, input
)
7116 || (GET_MODE (input
) != VOIDmode
7117 && GET_MODE (input
) != GET_MODE (output
)))
7120 /* We can't do anything if the output is also used as input,
7121 as we're going to overwrite it. */
7122 for (j
= 0; j
< ninputs
; j
++)
7123 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
7128 /* Avoid changing the same input several times. For
7129 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
7130 only change in once (to out1), rather than changing it
7131 first to out1 and afterwards to out2. */
7134 for (j
= 0; j
< noutputs
; j
++)
7135 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
7140 output_matched
[match
] = true;
7143 emit_move_insn (output
, input
);
7144 insns
= get_insns ();
7146 emit_insn_before (insns
, insn
);
7148 /* Now replace all mentions of the input with output. We can't
7149 just replace the occurrence in inputs[i], as the register might
7150 also be used in some other input (or even in an address of an
7151 output), which would mean possibly increasing the number of
7152 inputs by one (namely 'output' in addition), which might pose
7153 a too complicated problem for reload to solve. E.g. this situation:
7155 asm ("" : "=r" (output), "=m" (input) : "0" (input))
7157 Here 'input' is used in two occurrences as input (once for the
7158 input operand, once for the address in the second output operand).
7159 If we would replace only the occurrence of the input operand (to
7160 make the matching) we would be left with this:
7163 asm ("" : "=r" (output), "=m" (input) : "0" (output))
7165 Now we suddenly have two different input values (containing the same
7166 value, but different pseudos) where we formerly had only one.
7167 With more complicated asms this might lead to reload failures
7168 which wouldn't have happen without this pass. So, iterate over
7169 all operands and replace all occurrences of the register used. */
7170 for (j
= 0; j
< noutputs
; j
++)
7171 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
7172 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
7173 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
7175 for (j
= 0; j
< ninputs
; j
++)
7176 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
7177 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
7184 df_insn_rescan (insn
);
7188 rest_of_match_asm_constraints (void)
7191 rtx insn
, pat
, *p_sets
;
7194 if (!crtl
->has_asm_statement
)
7197 df_set_flags (DF_DEFER_INSN_RESCAN
);
7198 FOR_EACH_BB_FN (bb
, cfun
)
7200 FOR_BB_INSNS (bb
, insn
)
7205 pat
= PATTERN (insn
);
7206 if (GET_CODE (pat
) == PARALLEL
)
7207 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
7208 else if (GET_CODE (pat
) == SET
)
7209 p_sets
= &PATTERN (insn
), noutputs
= 1;
7213 if (GET_CODE (*p_sets
) == SET
7214 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
7215 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
7219 return TODO_df_finish
;
7224 const pass_data pass_data_match_asm_constraints
=
7226 RTL_PASS
, /* type */
7227 "asmcons", /* name */
7228 OPTGROUP_NONE
, /* optinfo_flags */
7229 true, /* has_execute */
7230 TV_NONE
, /* tv_id */
7231 0, /* properties_required */
7232 0, /* properties_provided */
7233 0, /* properties_destroyed */
7234 0, /* todo_flags_start */
7235 0, /* todo_flags_finish */
7238 class pass_match_asm_constraints
: public rtl_opt_pass
7241 pass_match_asm_constraints (gcc::context
*ctxt
)
7242 : rtl_opt_pass (pass_data_match_asm_constraints
, ctxt
)
7245 /* opt_pass methods: */
7246 unsigned int execute () { return rest_of_match_asm_constraints (); }
7248 }; // class pass_match_asm_constraints
7253 make_pass_match_asm_constraints (gcc::context
*ctxt
)
7255 return new pass_match_asm_constraints (ctxt
);
7259 #include "gt-function.h"