1 /* Expands front end tree to back end RTL for GCC.
2 Copyright (C) 1987, 1988, 1989, 1991, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf
;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging
;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs
;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated
;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no
;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function
* (*init_machine_status
) (void);
124 /* The currently compiled function. */
125 struct function
*cfun
= 0;
127 /* These hashes record the prologue and epilogue insns. */
128 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
129 htab_t prologue_insn_hash
;
130 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
131 htab_t epilogue_insn_hash
;
134 htab_t types_used_by_vars_hash
= NULL
;
135 tree types_used_by_cur_var_decl
= NULL
;
137 /* Forward declarations. */
139 static struct temp_slot
*find_temp_slot_from_address (rtx
);
140 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
141 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
142 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
143 static int all_blocks (tree
, tree
*);
144 static tree
*get_block_vector (tree
, int *);
145 extern tree
debug_find_var_in_block_tree (tree
, tree
);
146 /* We always define `record_insns' even if it's not used so that we
147 can always export `prologue_epilogue_contains'. */
148 static void record_insns (rtx
, rtx
, htab_t
*) ATTRIBUTE_UNUSED
;
149 static bool contains (const_rtx
, htab_t
);
151 static void emit_return_into_block (basic_block
);
153 static void prepare_function_start (void);
154 static void do_clobber_return_reg (rtx
, void *);
155 static void do_use_return_reg (rtx
, void *);
156 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
158 /* Stack of nested functions. */
159 /* Keep track of the cfun stack. */
161 typedef struct function
*function_p
;
163 DEF_VEC_P(function_p
);
164 DEF_VEC_ALLOC_P(function_p
,heap
);
165 static VEC(function_p
,heap
) *function_context_stack
;
167 /* Save the current context for compilation of a nested function.
168 This is called from language-specific code. */
171 push_function_context (void)
174 allocate_struct_function (NULL
, false);
176 VEC_safe_push (function_p
, heap
, function_context_stack
, cfun
);
180 /* Restore the last saved context, at the end of a nested function.
181 This function is called from language-specific code. */
184 pop_function_context (void)
186 struct function
*p
= VEC_pop (function_p
, function_context_stack
);
188 current_function_decl
= p
->decl
;
190 /* Reset variables that have known state during rtx generation. */
191 virtuals_instantiated
= 0;
192 generating_concat_p
= 1;
195 /* Clear out all parts of the state in F that can safely be discarded
196 after the function has been parsed, but not compiled, to let
197 garbage collection reclaim the memory. */
200 free_after_parsing (struct function
*f
)
205 /* Clear out all parts of the state in F that can safely be discarded
206 after the function has been compiled, to let garbage collection
207 reclaim the memory. */
210 free_after_compilation (struct function
*f
)
212 prologue_insn_hash
= NULL
;
213 epilogue_insn_hash
= NULL
;
215 if (crtl
->emit
.regno_pointer_align
)
216 free (crtl
->emit
.regno_pointer_align
);
218 memset (crtl
, 0, sizeof (struct rtl_data
));
223 regno_reg_rtx
= NULL
;
224 insn_locators_free ();
227 /* Return size needed for stack frame based on slots so far allocated.
228 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
229 the caller may have to do that. */
232 get_frame_size (void)
234 if (FRAME_GROWS_DOWNWARD
)
235 return -frame_offset
;
240 /* Issue an error message and return TRUE if frame OFFSET overflows in
241 the signed target pointer arithmetics for function FUNC. Otherwise
245 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
247 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
249 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
250 /* Leave room for the fixed part of the frame. */
251 - 64 * UNITS_PER_WORD
)
253 error_at (DECL_SOURCE_LOCATION (func
),
254 "total size of local objects too large");
261 /* Return stack slot alignment in bits for TYPE and MODE. */
264 get_stack_local_alignment (tree type
, enum machine_mode mode
)
266 unsigned int alignment
;
269 alignment
= BIGGEST_ALIGNMENT
;
271 alignment
= GET_MODE_ALIGNMENT (mode
);
273 /* Allow the frond-end to (possibly) increase the alignment of this
276 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
278 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
281 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
282 with machine mode MODE.
284 ALIGN controls the amount of alignment for the address of the slot:
285 0 means according to MODE,
286 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
287 -2 means use BITS_PER_UNIT,
288 positive specifies alignment boundary in bits.
290 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
292 We do not round to stack_boundary here. */
295 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
297 bool reduce_alignment_ok ATTRIBUTE_UNUSED
)
300 int bigend_correction
= 0;
301 unsigned int alignment
, alignment_in_bits
;
302 int frame_off
, frame_alignment
, frame_phase
;
306 alignment
= get_stack_local_alignment (NULL
, mode
);
307 alignment
/= BITS_PER_UNIT
;
309 else if (align
== -1)
311 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
312 size
= CEIL_ROUND (size
, alignment
);
314 else if (align
== -2)
315 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
317 alignment
= align
/ BITS_PER_UNIT
;
319 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
321 if (FRAME_GROWS_DOWNWARD
)
322 frame_offset
-= size
;
324 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
325 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
327 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
328 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
331 if (SUPPORTS_STACK_ALIGNMENT
)
333 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
335 if (!crtl
->stack_realign_processed
)
336 crtl
->stack_alignment_estimated
= alignment_in_bits
;
339 /* If stack is realigned and stack alignment value
340 hasn't been finalized, it is OK not to increase
341 stack_alignment_estimated. The bigger alignment
342 requirement is recorded in stack_alignment_needed
344 gcc_assert (!crtl
->stack_realign_finalized
);
345 if (!crtl
->stack_realign_needed
)
347 /* It is OK to reduce the alignment as long as the
348 requested size is 0 or the estimated stack
349 alignment >= mode alignment. */
350 gcc_assert (reduce_alignment_ok
352 || (crtl
->stack_alignment_estimated
353 >= GET_MODE_ALIGNMENT (mode
)));
354 alignment_in_bits
= crtl
->stack_alignment_estimated
;
355 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
361 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
362 crtl
->stack_alignment_needed
= alignment_in_bits
;
363 if (crtl
->max_used_stack_slot_alignment
< alignment_in_bits
)
364 crtl
->max_used_stack_slot_alignment
= alignment_in_bits
;
366 /* Calculate how many bytes the start of local variables is off from
368 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
369 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
370 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
372 /* Round the frame offset to the specified alignment. The default is
373 to always honor requests to align the stack but a port may choose to
374 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
375 if (STACK_ALIGNMENT_NEEDED
379 /* We must be careful here, since FRAME_OFFSET might be negative and
380 division with a negative dividend isn't as well defined as we might
381 like. So we instead assume that ALIGNMENT is a power of two and
382 use logical operations which are unambiguous. */
383 if (FRAME_GROWS_DOWNWARD
)
385 = (FLOOR_ROUND (frame_offset
- frame_phase
,
386 (unsigned HOST_WIDE_INT
) alignment
)
390 = (CEIL_ROUND (frame_offset
- frame_phase
,
391 (unsigned HOST_WIDE_INT
) alignment
)
395 /* On a big-endian machine, if we are allocating more space than we will use,
396 use the least significant bytes of those that are allocated. */
397 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
398 bigend_correction
= size
- GET_MODE_SIZE (mode
);
400 /* If we have already instantiated virtual registers, return the actual
401 address relative to the frame pointer. */
402 if (virtuals_instantiated
)
403 addr
= plus_constant (frame_pointer_rtx
,
405 (frame_offset
+ bigend_correction
406 + STARTING_FRAME_OFFSET
, Pmode
));
408 addr
= plus_constant (virtual_stack_vars_rtx
,
410 (frame_offset
+ bigend_correction
,
413 if (!FRAME_GROWS_DOWNWARD
)
414 frame_offset
+= size
;
416 x
= gen_rtx_MEM (mode
, addr
);
417 set_mem_align (x
, alignment_in_bits
);
418 MEM_NOTRAP_P (x
) = 1;
421 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
423 if (frame_offset_overflow (frame_offset
, current_function_decl
))
429 /* Wrap up assign_stack_local_1 with last parameter as false. */
432 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
434 return assign_stack_local_1 (mode
, size
, align
, false);
438 /* In order to evaluate some expressions, such as function calls returning
439 structures in memory, we need to temporarily allocate stack locations.
440 We record each allocated temporary in the following structure.
442 Associated with each temporary slot is a nesting level. When we pop up
443 one level, all temporaries associated with the previous level are freed.
444 Normally, all temporaries are freed after the execution of the statement
445 in which they were created. However, if we are inside a ({...}) grouping,
446 the result may be in a temporary and hence must be preserved. If the
447 result could be in a temporary, we preserve it if we can determine which
448 one it is in. If we cannot determine which temporary may contain the
449 result, all temporaries are preserved. A temporary is preserved by
450 pretending it was allocated at the previous nesting level.
452 Automatic variables are also assigned temporary slots, at the nesting
453 level where they are defined. They are marked a "kept" so that
454 free_temp_slots will not free them. */
456 struct GTY(()) temp_slot
{
457 /* Points to next temporary slot. */
458 struct temp_slot
*next
;
459 /* Points to previous temporary slot. */
460 struct temp_slot
*prev
;
461 /* The rtx to used to reference the slot. */
463 /* The size, in units, of the slot. */
465 /* The type of the object in the slot, or zero if it doesn't correspond
466 to a type. We use this to determine whether a slot can be reused.
467 It can be reused if objects of the type of the new slot will always
468 conflict with objects of the type of the old slot. */
470 /* The alignment (in bits) of the slot. */
472 /* Nonzero if this temporary is currently in use. */
474 /* Nonzero if this temporary has its address taken. */
476 /* Nesting level at which this slot is being used. */
478 /* Nonzero if this should survive a call to free_temp_slots. */
480 /* The offset of the slot from the frame_pointer, including extra space
481 for alignment. This info is for combine_temp_slots. */
482 HOST_WIDE_INT base_offset
;
483 /* The size of the slot, including extra space for alignment. This
484 info is for combine_temp_slots. */
485 HOST_WIDE_INT full_size
;
488 /* A table of addresses that represent a stack slot. The table is a mapping
489 from address RTXen to a temp slot. */
490 static GTY((param_is(struct temp_slot_address_entry
))) htab_t temp_slot_address_table
;
492 /* Entry for the above hash table. */
493 struct GTY(()) temp_slot_address_entry
{
496 struct temp_slot
*temp_slot
;
499 /* Removes temporary slot TEMP from LIST. */
502 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
505 temp
->next
->prev
= temp
->prev
;
507 temp
->prev
->next
= temp
->next
;
511 temp
->prev
= temp
->next
= NULL
;
514 /* Inserts temporary slot TEMP to LIST. */
517 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
521 (*list
)->prev
= temp
;
526 /* Returns the list of used temp slots at LEVEL. */
528 static struct temp_slot
**
529 temp_slots_at_level (int level
)
531 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
532 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
534 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
537 /* Returns the maximal temporary slot level. */
540 max_slot_level (void)
542 if (!used_temp_slots
)
545 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
548 /* Moves temporary slot TEMP to LEVEL. */
551 move_slot_to_level (struct temp_slot
*temp
, int level
)
553 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
554 insert_slot_to_list (temp
, temp_slots_at_level (level
));
558 /* Make temporary slot TEMP available. */
561 make_slot_available (struct temp_slot
*temp
)
563 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
564 insert_slot_to_list (temp
, &avail_temp_slots
);
569 /* Compute the hash value for an address -> temp slot mapping.
570 The value is cached on the mapping entry. */
572 temp_slot_address_compute_hash (struct temp_slot_address_entry
*t
)
574 int do_not_record
= 0;
575 return hash_rtx (t
->address
, GET_MODE (t
->address
),
576 &do_not_record
, NULL
, false);
579 /* Return the hash value for an address -> temp slot mapping. */
581 temp_slot_address_hash (const void *p
)
583 const struct temp_slot_address_entry
*t
;
584 t
= (const struct temp_slot_address_entry
*) p
;
588 /* Compare two address -> temp slot mapping entries. */
590 temp_slot_address_eq (const void *p1
, const void *p2
)
592 const struct temp_slot_address_entry
*t1
, *t2
;
593 t1
= (const struct temp_slot_address_entry
*) p1
;
594 t2
= (const struct temp_slot_address_entry
*) p2
;
595 return exp_equiv_p (t1
->address
, t2
->address
, 0, true);
598 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
600 insert_temp_slot_address (rtx address
, struct temp_slot
*temp_slot
)
603 struct temp_slot_address_entry
*t
= GGC_NEW (struct temp_slot_address_entry
);
604 t
->address
= address
;
605 t
->temp_slot
= temp_slot
;
606 t
->hash
= temp_slot_address_compute_hash (t
);
607 slot
= htab_find_slot_with_hash (temp_slot_address_table
, t
, t
->hash
, INSERT
);
611 /* Remove an address -> temp slot mapping entry if the temp slot is
612 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
614 remove_unused_temp_slot_addresses_1 (void **slot
, void *data ATTRIBUTE_UNUSED
)
616 const struct temp_slot_address_entry
*t
;
617 t
= (const struct temp_slot_address_entry
*) *slot
;
618 if (! t
->temp_slot
->in_use
)
623 /* Remove all mappings of addresses to unused temp slots. */
625 remove_unused_temp_slot_addresses (void)
627 htab_traverse (temp_slot_address_table
,
628 remove_unused_temp_slot_addresses_1
,
632 /* Find the temp slot corresponding to the object at address X. */
634 static struct temp_slot
*
635 find_temp_slot_from_address (rtx x
)
638 struct temp_slot_address_entry tmp
, *t
;
640 /* First try the easy way:
641 See if X exists in the address -> temp slot mapping. */
643 tmp
.temp_slot
= NULL
;
644 tmp
.hash
= temp_slot_address_compute_hash (&tmp
);
645 t
= (struct temp_slot_address_entry
*)
646 htab_find_with_hash (temp_slot_address_table
, &tmp
, tmp
.hash
);
650 /* If we have a sum involving a register, see if it points to a temp
652 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
653 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
655 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
656 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
659 /* Last resort: Address is a virtual stack var address. */
660 if (GET_CODE (x
) == PLUS
661 && XEXP (x
, 0) == virtual_stack_vars_rtx
662 && CONST_INT_P (XEXP (x
, 1)))
665 for (i
= max_slot_level (); i
>= 0; i
--)
666 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
668 if (INTVAL (XEXP (x
, 1)) >= p
->base_offset
669 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
)
677 /* Allocate a temporary stack slot and record it for possible later
680 MODE is the machine mode to be given to the returned rtx.
682 SIZE is the size in units of the space required. We do no rounding here
683 since assign_stack_local will do any required rounding.
685 KEEP is 1 if this slot is to be retained after a call to
686 free_temp_slots. Automatic variables for a block are allocated
687 with this flag. KEEP values of 2 or 3 were needed respectively
688 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
689 or for SAVE_EXPRs, but they are now unused.
691 TYPE is the type that will be used for the stack slot. */
694 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
698 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
701 /* If SIZE is -1 it means that somebody tried to allocate a temporary
702 of a variable size. */
703 gcc_assert (size
!= -1);
705 /* These are now unused. */
706 gcc_assert (keep
<= 1);
708 align
= get_stack_local_alignment (type
, mode
);
710 /* Try to find an available, already-allocated temporary of the proper
711 mode which meets the size and alignment requirements. Choose the
712 smallest one with the closest alignment.
714 If assign_stack_temp is called outside of the tree->rtl expansion,
715 we cannot reuse the stack slots (that may still refer to
716 VIRTUAL_STACK_VARS_REGNUM). */
717 if (!virtuals_instantiated
)
719 for (p
= avail_temp_slots
; p
; p
= p
->next
)
721 if (p
->align
>= align
&& p
->size
>= size
722 && GET_MODE (p
->slot
) == mode
723 && objects_must_conflict_p (p
->type
, type
)
724 && (best_p
== 0 || best_p
->size
> p
->size
725 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
727 if (p
->align
== align
&& p
->size
== size
)
730 cut_slot_from_list (selected
, &avail_temp_slots
);
739 /* Make our best, if any, the one to use. */
743 cut_slot_from_list (selected
, &avail_temp_slots
);
745 /* If there are enough aligned bytes left over, make them into a new
746 temp_slot so that the extra bytes don't get wasted. Do this only
747 for BLKmode slots, so that we can be sure of the alignment. */
748 if (GET_MODE (best_p
->slot
) == BLKmode
)
750 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
751 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
753 if (best_p
->size
- rounded_size
>= alignment
)
755 p
= GGC_NEW (struct temp_slot
);
756 p
->in_use
= p
->addr_taken
= 0;
757 p
->size
= best_p
->size
- rounded_size
;
758 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
759 p
->full_size
= best_p
->full_size
- rounded_size
;
760 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
761 p
->align
= best_p
->align
;
762 p
->type
= best_p
->type
;
763 insert_slot_to_list (p
, &avail_temp_slots
);
765 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
768 best_p
->size
= rounded_size
;
769 best_p
->full_size
= rounded_size
;
774 /* If we still didn't find one, make a new temporary. */
777 HOST_WIDE_INT frame_offset_old
= frame_offset
;
779 p
= GGC_NEW (struct temp_slot
);
781 /* We are passing an explicit alignment request to assign_stack_local.
782 One side effect of that is assign_stack_local will not round SIZE
783 to ensure the frame offset remains suitably aligned.
785 So for requests which depended on the rounding of SIZE, we go ahead
786 and round it now. We also make sure ALIGNMENT is at least
787 BIGGEST_ALIGNMENT. */
788 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
789 p
->slot
= assign_stack_local (mode
,
791 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
797 /* The following slot size computation is necessary because we don't
798 know the actual size of the temporary slot until assign_stack_local
799 has performed all the frame alignment and size rounding for the
800 requested temporary. Note that extra space added for alignment
801 can be either above or below this stack slot depending on which
802 way the frame grows. We include the extra space if and only if it
803 is above this slot. */
804 if (FRAME_GROWS_DOWNWARD
)
805 p
->size
= frame_offset_old
- frame_offset
;
809 /* Now define the fields used by combine_temp_slots. */
810 if (FRAME_GROWS_DOWNWARD
)
812 p
->base_offset
= frame_offset
;
813 p
->full_size
= frame_offset_old
- frame_offset
;
817 p
->base_offset
= frame_offset_old
;
818 p
->full_size
= frame_offset
- frame_offset_old
;
828 p
->level
= temp_slot_level
;
831 pp
= temp_slots_at_level (p
->level
);
832 insert_slot_to_list (p
, pp
);
833 insert_temp_slot_address (XEXP (p
->slot
, 0), p
);
835 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
836 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
837 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
839 /* If we know the alias set for the memory that will be used, use
840 it. If there's no TYPE, then we don't know anything about the
841 alias set for the memory. */
842 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
843 set_mem_align (slot
, align
);
845 /* If a type is specified, set the relevant flags. */
848 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
849 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
850 || TREE_CODE (type
) == COMPLEX_TYPE
));
852 MEM_NOTRAP_P (slot
) = 1;
857 /* Allocate a temporary stack slot and record it for possible later
858 reuse. First three arguments are same as in preceding function. */
861 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
863 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
866 /* Assign a temporary.
867 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
868 and so that should be used in error messages. In either case, we
869 allocate of the given type.
870 KEEP is as for assign_stack_temp.
871 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
872 it is 0 if a register is OK.
873 DONT_PROMOTE is 1 if we should not promote values in register
877 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
878 int dont_promote ATTRIBUTE_UNUSED
)
881 enum machine_mode mode
;
886 if (DECL_P (type_or_decl
))
887 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
889 decl
= NULL
, type
= type_or_decl
;
891 mode
= TYPE_MODE (type
);
893 unsignedp
= TYPE_UNSIGNED (type
);
896 if (mode
== BLKmode
|| memory_required
)
898 HOST_WIDE_INT size
= int_size_in_bytes (type
);
901 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
902 problems with allocating the stack space. */
906 /* Unfortunately, we don't yet know how to allocate variable-sized
907 temporaries. However, sometimes we can find a fixed upper limit on
908 the size, so try that instead. */
910 size
= max_int_size_in_bytes (type
);
912 /* The size of the temporary may be too large to fit into an integer. */
913 /* ??? Not sure this should happen except for user silliness, so limit
914 this to things that aren't compiler-generated temporaries. The
915 rest of the time we'll die in assign_stack_temp_for_type. */
916 if (decl
&& size
== -1
917 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
919 error ("size of variable %q+D is too large", decl
);
923 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
929 mode
= promote_mode (type
, mode
, &unsignedp
);
932 return gen_reg_rtx (mode
);
935 /* Combine temporary stack slots which are adjacent on the stack.
937 This allows for better use of already allocated stack space. This is only
938 done for BLKmode slots because we can be sure that we won't have alignment
939 problems in this case. */
942 combine_temp_slots (void)
944 struct temp_slot
*p
, *q
, *next
, *next_q
;
947 /* We can't combine slots, because the information about which slot
948 is in which alias set will be lost. */
949 if (flag_strict_aliasing
)
952 /* If there are a lot of temp slots, don't do anything unless
953 high levels of optimization. */
954 if (! flag_expensive_optimizations
)
955 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
956 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
959 for (p
= avail_temp_slots
; p
; p
= next
)
965 if (GET_MODE (p
->slot
) != BLKmode
)
968 for (q
= p
->next
; q
; q
= next_q
)
974 if (GET_MODE (q
->slot
) != BLKmode
)
977 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
979 /* Q comes after P; combine Q into P. */
981 p
->full_size
+= q
->full_size
;
984 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
986 /* P comes after Q; combine P into Q. */
988 q
->full_size
+= p
->full_size
;
993 cut_slot_from_list (q
, &avail_temp_slots
);
996 /* Either delete P or advance past it. */
998 cut_slot_from_list (p
, &avail_temp_slots
);
1002 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1003 slot that previously was known by OLD_RTX. */
1006 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
1008 struct temp_slot
*p
;
1010 if (rtx_equal_p (old_rtx
, new_rtx
))
1013 p
= find_temp_slot_from_address (old_rtx
);
1015 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1016 NEW_RTX is a register, see if one operand of the PLUS is a
1017 temporary location. If so, NEW_RTX points into it. Otherwise,
1018 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1019 in common between them. If so, try a recursive call on those
1023 if (GET_CODE (old_rtx
) != PLUS
)
1026 if (REG_P (new_rtx
))
1028 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
1029 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
1032 else if (GET_CODE (new_rtx
) != PLUS
)
1035 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
1036 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
1037 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
1038 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
1039 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
1040 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
1041 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
1042 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
1047 /* Otherwise add an alias for the temp's address. */
1048 insert_temp_slot_address (new_rtx
, p
);
1051 /* If X could be a reference to a temporary slot, mark the fact that its
1052 address was taken. */
1055 mark_temp_addr_taken (rtx x
)
1057 struct temp_slot
*p
;
1062 /* If X is not in memory or is at a constant address, it cannot be in
1063 a temporary slot. */
1064 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1067 p
= find_temp_slot_from_address (XEXP (x
, 0));
1072 /* If X could be a reference to a temporary slot, mark that slot as
1073 belonging to the to one level higher than the current level. If X
1074 matched one of our slots, just mark that one. Otherwise, we can't
1075 easily predict which it is, so upgrade all of them. Kept slots
1076 need not be touched.
1078 This is called when an ({...}) construct occurs and a statement
1079 returns a value in memory. */
1082 preserve_temp_slots (rtx x
)
1084 struct temp_slot
*p
= 0, *next
;
1086 /* If there is no result, we still might have some objects whose address
1087 were taken, so we need to make sure they stay around. */
1090 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1095 move_slot_to_level (p
, temp_slot_level
- 1);
1101 /* If X is a register that is being used as a pointer, see if we have
1102 a temporary slot we know it points to. To be consistent with
1103 the code below, we really should preserve all non-kept slots
1104 if we can't find a match, but that seems to be much too costly. */
1105 if (REG_P (x
) && REG_POINTER (x
))
1106 p
= find_temp_slot_from_address (x
);
1108 /* If X is not in memory or is at a constant address, it cannot be in
1109 a temporary slot, but it can contain something whose address was
1111 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1113 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1118 move_slot_to_level (p
, temp_slot_level
- 1);
1124 /* First see if we can find a match. */
1126 p
= find_temp_slot_from_address (XEXP (x
, 0));
1130 /* Move everything at our level whose address was taken to our new
1131 level in case we used its address. */
1132 struct temp_slot
*q
;
1134 if (p
->level
== temp_slot_level
)
1136 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1140 if (p
!= q
&& q
->addr_taken
)
1141 move_slot_to_level (q
, temp_slot_level
- 1);
1144 move_slot_to_level (p
, temp_slot_level
- 1);
1150 /* Otherwise, preserve all non-kept slots at this level. */
1151 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1156 move_slot_to_level (p
, temp_slot_level
- 1);
1160 /* Free all temporaries used so far. This is normally called at the
1161 end of generating code for a statement. */
1164 free_temp_slots (void)
1166 struct temp_slot
*p
, *next
;
1168 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1173 make_slot_available (p
);
1176 remove_unused_temp_slot_addresses ();
1177 combine_temp_slots ();
1180 /* Push deeper into the nesting level for stack temporaries. */
1183 push_temp_slots (void)
1188 /* Pop a temporary nesting level. All slots in use in the current level
1192 pop_temp_slots (void)
1194 struct temp_slot
*p
, *next
;
1196 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1199 make_slot_available (p
);
1202 remove_unused_temp_slot_addresses ();
1203 combine_temp_slots ();
1208 /* Initialize temporary slots. */
1211 init_temp_slots (void)
1213 /* We have not allocated any temporaries yet. */
1214 avail_temp_slots
= 0;
1215 used_temp_slots
= 0;
1216 temp_slot_level
= 0;
1218 /* Set up the table to map addresses to temp slots. */
1219 if (! temp_slot_address_table
)
1220 temp_slot_address_table
= htab_create_ggc (32,
1221 temp_slot_address_hash
,
1222 temp_slot_address_eq
,
1225 htab_empty (temp_slot_address_table
);
1228 /* These routines are responsible for converting virtual register references
1229 to the actual hard register references once RTL generation is complete.
1231 The following four variables are used for communication between the
1232 routines. They contain the offsets of the virtual registers from their
1233 respective hard registers. */
1235 static int in_arg_offset
;
1236 static int var_offset
;
1237 static int dynamic_offset
;
1238 static int out_arg_offset
;
1239 static int cfa_offset
;
1241 /* In most machines, the stack pointer register is equivalent to the bottom
1244 #ifndef STACK_POINTER_OFFSET
1245 #define STACK_POINTER_OFFSET 0
1248 /* If not defined, pick an appropriate default for the offset of dynamically
1249 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1250 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1252 #ifndef STACK_DYNAMIC_OFFSET
1254 /* The bottom of the stack points to the actual arguments. If
1255 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1256 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1257 stack space for register parameters is not pushed by the caller, but
1258 rather part of the fixed stack areas and hence not included in
1259 `crtl->outgoing_args_size'. Nevertheless, we must allow
1260 for it when allocating stack dynamic objects. */
1262 #if defined(REG_PARM_STACK_SPACE)
1263 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1264 ((ACCUMULATE_OUTGOING_ARGS \
1265 ? (crtl->outgoing_args_size \
1266 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1267 : REG_PARM_STACK_SPACE (FNDECL))) \
1268 : 0) + (STACK_POINTER_OFFSET))
1270 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1271 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1272 + (STACK_POINTER_OFFSET))
1277 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1278 is a virtual register, return the equivalent hard register and set the
1279 offset indirectly through the pointer. Otherwise, return 0. */
1282 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1285 HOST_WIDE_INT offset
;
1287 if (x
== virtual_incoming_args_rtx
)
1289 if (stack_realign_drap
)
1291 /* Replace virtual_incoming_args_rtx with internal arg
1292 pointer if DRAP is used to realign stack. */
1293 new_rtx
= crtl
->args
.internal_arg_pointer
;
1297 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1299 else if (x
== virtual_stack_vars_rtx
)
1300 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1301 else if (x
== virtual_stack_dynamic_rtx
)
1302 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1303 else if (x
== virtual_outgoing_args_rtx
)
1304 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1305 else if (x
== virtual_cfa_rtx
)
1307 #ifdef FRAME_POINTER_CFA_OFFSET
1308 new_rtx
= frame_pointer_rtx
;
1310 new_rtx
= arg_pointer_rtx
;
1312 offset
= cfa_offset
;
1321 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1322 Instantiate any virtual registers present inside of *LOC. The expression
1323 is simplified, as much as possible, but is not to be considered "valid"
1324 in any sense implied by the target. If any change is made, set CHANGED
1328 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1330 HOST_WIDE_INT offset
;
1331 bool *changed
= (bool *) data
;
1338 switch (GET_CODE (x
))
1341 new_rtx
= instantiate_new_reg (x
, &offset
);
1344 *loc
= plus_constant (new_rtx
, offset
);
1351 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1354 new_rtx
= plus_constant (new_rtx
, offset
);
1355 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1361 /* FIXME -- from old code */
1362 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1363 we can commute the PLUS and SUBREG because pointers into the
1364 frame are well-behaved. */
1374 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1375 matches the predicate for insn CODE operand OPERAND. */
1378 safe_insn_predicate (int code
, int operand
, rtx x
)
1380 const struct insn_operand_data
*op_data
;
1385 op_data
= &insn_data
[code
].operand
[operand
];
1386 if (op_data
->predicate
== NULL
)
1389 return op_data
->predicate (x
, op_data
->mode
);
1392 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1393 registers present inside of insn. The result will be a valid insn. */
1396 instantiate_virtual_regs_in_insn (rtx insn
)
1398 HOST_WIDE_INT offset
;
1400 bool any_change
= false;
1401 rtx set
, new_rtx
, x
, seq
;
1403 /* There are some special cases to be handled first. */
1404 set
= single_set (insn
);
1407 /* We're allowed to assign to a virtual register. This is interpreted
1408 to mean that the underlying register gets assigned the inverse
1409 transformation. This is used, for example, in the handling of
1411 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1416 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1417 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1419 x
= force_operand (x
, new_rtx
);
1421 emit_move_insn (new_rtx
, x
);
1426 emit_insn_before (seq
, insn
);
1431 /* Handle a straight copy from a virtual register by generating a
1432 new add insn. The difference between this and falling through
1433 to the generic case is avoiding a new pseudo and eliminating a
1434 move insn in the initial rtl stream. */
1435 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1436 if (new_rtx
&& offset
!= 0
1437 && REG_P (SET_DEST (set
))
1438 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1442 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1443 new_rtx
, GEN_INT (offset
), SET_DEST (set
),
1444 1, OPTAB_LIB_WIDEN
);
1445 if (x
!= SET_DEST (set
))
1446 emit_move_insn (SET_DEST (set
), x
);
1451 emit_insn_before (seq
, insn
);
1456 extract_insn (insn
);
1457 insn_code
= INSN_CODE (insn
);
1459 /* Handle a plus involving a virtual register by determining if the
1460 operands remain valid if they're modified in place. */
1461 if (GET_CODE (SET_SRC (set
)) == PLUS
1462 && recog_data
.n_operands
>= 3
1463 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1464 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1465 && CONST_INT_P (recog_data
.operand
[2])
1466 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1468 offset
+= INTVAL (recog_data
.operand
[2]);
1470 /* If the sum is zero, then replace with a plain move. */
1472 && REG_P (SET_DEST (set
))
1473 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1476 emit_move_insn (SET_DEST (set
), new_rtx
);
1480 emit_insn_before (seq
, insn
);
1485 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1487 /* Using validate_change and apply_change_group here leaves
1488 recog_data in an invalid state. Since we know exactly what
1489 we want to check, do those two by hand. */
1490 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1491 && safe_insn_predicate (insn_code
, 2, x
))
1493 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1494 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1497 /* Fall through into the regular operand fixup loop in
1498 order to take care of operands other than 1 and 2. */
1504 extract_insn (insn
);
1505 insn_code
= INSN_CODE (insn
);
1508 /* In the general case, we expect virtual registers to appear only in
1509 operands, and then only as either bare registers or inside memories. */
1510 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1512 x
= recog_data
.operand
[i
];
1513 switch (GET_CODE (x
))
1517 rtx addr
= XEXP (x
, 0);
1518 bool changed
= false;
1520 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1525 x
= replace_equiv_address (x
, addr
);
1526 /* It may happen that the address with the virtual reg
1527 was valid (e.g. based on the virtual stack reg, which might
1528 be acceptable to the predicates with all offsets), whereas
1529 the address now isn't anymore, for instance when the address
1530 is still offsetted, but the base reg isn't virtual-stack-reg
1531 anymore. Below we would do a force_reg on the whole operand,
1532 but this insn might actually only accept memory. Hence,
1533 before doing that last resort, try to reload the address into
1534 a register, so this operand stays a MEM. */
1535 if (!safe_insn_predicate (insn_code
, i
, x
))
1537 addr
= force_reg (GET_MODE (addr
), addr
);
1538 x
= replace_equiv_address (x
, addr
);
1543 emit_insn_before (seq
, insn
);
1548 new_rtx
= instantiate_new_reg (x
, &offset
);
1549 if (new_rtx
== NULL
)
1557 /* Careful, special mode predicates may have stuff in
1558 insn_data[insn_code].operand[i].mode that isn't useful
1559 to us for computing a new value. */
1560 /* ??? Recognize address_operand and/or "p" constraints
1561 to see if (plus new offset) is a valid before we put
1562 this through expand_simple_binop. */
1563 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1564 GEN_INT (offset
), NULL_RTX
,
1565 1, OPTAB_LIB_WIDEN
);
1568 emit_insn_before (seq
, insn
);
1573 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1574 if (new_rtx
== NULL
)
1579 new_rtx
= expand_simple_binop (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1580 GEN_INT (offset
), NULL_RTX
,
1581 1, OPTAB_LIB_WIDEN
);
1584 emit_insn_before (seq
, insn
);
1586 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1587 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1595 /* At this point, X contains the new value for the operand.
1596 Validate the new value vs the insn predicate. Note that
1597 asm insns will have insn_code -1 here. */
1598 if (!safe_insn_predicate (insn_code
, i
, x
))
1601 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1605 emit_insn_before (seq
, insn
);
1608 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1614 /* Propagate operand changes into the duplicates. */
1615 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1616 *recog_data
.dup_loc
[i
]
1617 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1619 /* Force re-recognition of the instruction for validation. */
1620 INSN_CODE (insn
) = -1;
1623 if (asm_noperands (PATTERN (insn
)) >= 0)
1625 if (!check_asm_operands (PATTERN (insn
)))
1627 error_for_asm (insn
, "impossible constraint in %<asm%>");
1633 if (recog_memoized (insn
) < 0)
1634 fatal_insn_not_found (insn
);
1638 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1639 do any instantiation required. */
1642 instantiate_decl_rtl (rtx x
)
1649 /* If this is a CONCAT, recurse for the pieces. */
1650 if (GET_CODE (x
) == CONCAT
)
1652 instantiate_decl_rtl (XEXP (x
, 0));
1653 instantiate_decl_rtl (XEXP (x
, 1));
1657 /* If this is not a MEM, no need to do anything. Similarly if the
1658 address is a constant or a register that is not a virtual register. */
1663 if (CONSTANT_P (addr
)
1665 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1666 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1669 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1672 /* Helper for instantiate_decls called via walk_tree: Process all decls
1673 in the given DECL_VALUE_EXPR. */
1676 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1682 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1683 instantiate_decl_rtl (DECL_RTL (t
));
1688 /* Subroutine of instantiate_decls: Process all decls in the given
1689 BLOCK node and all its subblocks. */
1692 instantiate_decls_1 (tree let
)
1696 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1698 if (DECL_RTL_SET_P (t
))
1699 instantiate_decl_rtl (DECL_RTL (t
));
1700 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1702 tree v
= DECL_VALUE_EXPR (t
);
1703 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1707 /* Process all subblocks. */
1708 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1709 instantiate_decls_1 (t
);
1712 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1713 all virtual registers in their DECL_RTL's. */
1716 instantiate_decls (tree fndecl
)
1720 /* Process all parameters of the function. */
1721 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1723 instantiate_decl_rtl (DECL_RTL (decl
));
1724 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1725 if (DECL_HAS_VALUE_EXPR_P (decl
))
1727 tree v
= DECL_VALUE_EXPR (decl
);
1728 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1732 /* Now process all variables defined in the function or its subblocks. */
1733 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1735 t
= cfun
->local_decls
;
1736 cfun
->local_decls
= NULL_TREE
;
1739 next
= TREE_CHAIN (t
);
1740 decl
= TREE_VALUE (t
);
1741 if (DECL_RTL_SET_P (decl
))
1742 instantiate_decl_rtl (DECL_RTL (decl
));
1747 /* Pass through the INSNS of function FNDECL and convert virtual register
1748 references to hard register references. */
1751 instantiate_virtual_regs (void)
1755 /* Compute the offsets to use for this function. */
1756 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1757 var_offset
= STARTING_FRAME_OFFSET
;
1758 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1759 out_arg_offset
= STACK_POINTER_OFFSET
;
1760 #ifdef FRAME_POINTER_CFA_OFFSET
1761 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1763 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1766 /* Initialize recognition, indicating that volatile is OK. */
1769 /* Scan through all the insns, instantiating every virtual register still
1771 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1774 /* These patterns in the instruction stream can never be recognized.
1775 Fortunately, they shouldn't contain virtual registers either. */
1776 if (GET_CODE (PATTERN (insn
)) == USE
1777 || GET_CODE (PATTERN (insn
)) == CLOBBER
1778 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1779 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1780 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1782 else if (DEBUG_INSN_P (insn
))
1783 for_each_rtx (&INSN_VAR_LOCATION (insn
),
1784 instantiate_virtual_regs_in_rtx
, NULL
);
1786 instantiate_virtual_regs_in_insn (insn
);
1788 if (INSN_DELETED_P (insn
))
1791 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1793 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1795 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1796 instantiate_virtual_regs_in_rtx
, NULL
);
1799 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1800 instantiate_decls (current_function_decl
);
1802 targetm
.instantiate_decls ();
1804 /* Indicate that, from now on, assign_stack_local should use
1805 frame_pointer_rtx. */
1806 virtuals_instantiated
= 1;
1810 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1816 instantiate_virtual_regs
, /* execute */
1819 0, /* static_pass_number */
1820 TV_NONE
, /* tv_id */
1821 0, /* properties_required */
1822 0, /* properties_provided */
1823 0, /* properties_destroyed */
1824 0, /* todo_flags_start */
1825 TODO_dump_func
/* todo_flags_finish */
1830 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1831 This means a type for which function calls must pass an address to the
1832 function or get an address back from the function.
1833 EXP may be a type node or an expression (whose type is tested). */
1836 aggregate_value_p (const_tree exp
, const_tree fntype
)
1838 int i
, regno
, nregs
;
1841 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1843 /* DECL node associated with FNTYPE when relevant, which we might need to
1844 check for by-invisible-reference returns, typically for CALL_EXPR input
1846 const_tree fndecl
= NULL_TREE
;
1849 switch (TREE_CODE (fntype
))
1852 fndecl
= get_callee_fndecl (fntype
);
1854 ? TREE_TYPE (fndecl
)
1855 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype
))));
1859 fntype
= TREE_TYPE (fndecl
);
1864 case IDENTIFIER_NODE
:
1868 /* We don't expect other rtl types here. */
1872 if (TREE_CODE (type
) == VOID_TYPE
)
1875 /* If the front end has decided that this needs to be passed by
1876 reference, do so. */
1877 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1878 && DECL_BY_REFERENCE (exp
))
1881 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1882 called function RESULT_DECL, meaning the function returns in memory by
1883 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1884 on the function type, which used to be the way to request such a return
1885 mechanism but might now be causing troubles at gimplification time if
1886 temporaries with the function type need to be created. */
1887 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1888 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1891 if (targetm
.calls
.return_in_memory (type
, fntype
))
1893 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1894 and thus can't be returned in registers. */
1895 if (TREE_ADDRESSABLE (type
))
1897 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1899 /* Make sure we have suitable call-clobbered regs to return
1900 the value in; if not, we must return it in memory. */
1901 reg
= hard_function_value (type
, 0, fntype
, 0);
1903 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1908 regno
= REGNO (reg
);
1909 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1910 for (i
= 0; i
< nregs
; i
++)
1911 if (! call_used_regs
[regno
+ i
])
1916 /* Return true if we should assign DECL a pseudo register; false if it
1917 should live on the local stack. */
1920 use_register_for_decl (const_tree decl
)
1922 if (!targetm
.calls
.allocate_stack_slots_for_args())
1925 /* Honor volatile. */
1926 if (TREE_SIDE_EFFECTS (decl
))
1929 /* Honor addressability. */
1930 if (TREE_ADDRESSABLE (decl
))
1933 /* Only register-like things go in registers. */
1934 if (DECL_MODE (decl
) == BLKmode
)
1937 /* If -ffloat-store specified, don't put explicit float variables
1939 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1940 propagates values across these stores, and it probably shouldn't. */
1941 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1944 /* If we're not interested in tracking debugging information for
1945 this decl, then we can certainly put it in a register. */
1946 if (DECL_IGNORED_P (decl
))
1952 if (!DECL_REGISTER (decl
))
1955 switch (TREE_CODE (TREE_TYPE (decl
)))
1959 case QUAL_UNION_TYPE
:
1960 /* When not optimizing, disregard register keyword for variables with
1961 types containing methods, otherwise the methods won't be callable
1962 from the debugger. */
1963 if (TYPE_METHODS (TREE_TYPE (decl
)))
1973 /* Return true if TYPE should be passed by invisible reference. */
1976 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1977 tree type
, bool named_arg
)
1981 /* If this type contains non-trivial constructors, then it is
1982 forbidden for the middle-end to create any new copies. */
1983 if (TREE_ADDRESSABLE (type
))
1986 /* GCC post 3.4 passes *all* variable sized types by reference. */
1987 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1991 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1994 /* Return true if TYPE, which is passed by reference, should be callee
1995 copied instead of caller copied. */
1998 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1999 tree type
, bool named_arg
)
2001 if (type
&& TREE_ADDRESSABLE (type
))
2003 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
2006 /* Structures to communicate between the subroutines of assign_parms.
2007 The first holds data persistent across all parameters, the second
2008 is cleared out for each parameter. */
2010 struct assign_parm_data_all
2012 CUMULATIVE_ARGS args_so_far
;
2013 struct args_size stack_args_size
;
2014 tree function_result_decl
;
2016 rtx first_conversion_insn
;
2017 rtx last_conversion_insn
;
2018 HOST_WIDE_INT pretend_args_size
;
2019 HOST_WIDE_INT extra_pretend_bytes
;
2020 int reg_parm_stack_space
;
2023 struct assign_parm_data_one
2029 enum machine_mode nominal_mode
;
2030 enum machine_mode passed_mode
;
2031 enum machine_mode promoted_mode
;
2032 struct locate_and_pad_arg_data locate
;
2034 BOOL_BITFIELD named_arg
: 1;
2035 BOOL_BITFIELD passed_pointer
: 1;
2036 BOOL_BITFIELD on_stack
: 1;
2037 BOOL_BITFIELD loaded_in_reg
: 1;
2040 /* A subroutine of assign_parms. Initialize ALL. */
2043 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2047 memset (all
, 0, sizeof (*all
));
2049 fntype
= TREE_TYPE (current_function_decl
);
2051 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2052 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
2054 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
2055 current_function_decl
, -1);
2058 #ifdef REG_PARM_STACK_SPACE
2059 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
2063 /* If ARGS contains entries with complex types, split the entry into two
2064 entries of the component type. Return a new list of substitutions are
2065 needed, else the old list. */
2068 split_complex_args (tree args
)
2072 /* Before allocating memory, check for the common case of no complex. */
2073 for (p
= args
; p
; p
= TREE_CHAIN (p
))
2075 tree type
= TREE_TYPE (p
);
2076 if (TREE_CODE (type
) == COMPLEX_TYPE
2077 && targetm
.calls
.split_complex_arg (type
))
2083 args
= copy_list (args
);
2085 for (p
= args
; p
; p
= TREE_CHAIN (p
))
2087 tree type
= TREE_TYPE (p
);
2088 if (TREE_CODE (type
) == COMPLEX_TYPE
2089 && targetm
.calls
.split_complex_arg (type
))
2092 tree subtype
= TREE_TYPE (type
);
2093 bool addressable
= TREE_ADDRESSABLE (p
);
2095 /* Rewrite the PARM_DECL's type with its component. */
2096 TREE_TYPE (p
) = subtype
;
2097 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2098 DECL_MODE (p
) = VOIDmode
;
2099 DECL_SIZE (p
) = NULL
;
2100 DECL_SIZE_UNIT (p
) = NULL
;
2101 /* If this arg must go in memory, put it in a pseudo here.
2102 We can't allow it to go in memory as per normal parms,
2103 because the usual place might not have the imag part
2104 adjacent to the real part. */
2105 DECL_ARTIFICIAL (p
) = addressable
;
2106 DECL_IGNORED_P (p
) = addressable
;
2107 TREE_ADDRESSABLE (p
) = 0;
2110 /* Build a second synthetic decl. */
2111 decl
= build_decl (EXPR_LOCATION (p
),
2112 PARM_DECL
, NULL_TREE
, subtype
);
2113 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2114 DECL_ARTIFICIAL (decl
) = addressable
;
2115 DECL_IGNORED_P (decl
) = addressable
;
2116 layout_decl (decl
, 0);
2118 /* Splice it in; skip the new decl. */
2119 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
2120 TREE_CHAIN (p
) = decl
;
2128 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2129 the hidden struct return argument, and (abi willing) complex args.
2130 Return the new parameter list. */
2133 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2135 tree fndecl
= current_function_decl
;
2136 tree fntype
= TREE_TYPE (fndecl
);
2137 tree fnargs
= DECL_ARGUMENTS (fndecl
);
2139 /* If struct value address is treated as the first argument, make it so. */
2140 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2141 && ! cfun
->returns_pcc_struct
2142 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2144 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2147 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2148 PARM_DECL
, NULL_TREE
, type
);
2149 DECL_ARG_TYPE (decl
) = type
;
2150 DECL_ARTIFICIAL (decl
) = 1;
2151 DECL_IGNORED_P (decl
) = 1;
2153 TREE_CHAIN (decl
) = fnargs
;
2155 all
->function_result_decl
= decl
;
2158 all
->orig_fnargs
= fnargs
;
2160 /* If the target wants to split complex arguments into scalars, do so. */
2161 if (targetm
.calls
.split_complex_arg
)
2162 fnargs
= split_complex_args (fnargs
);
2167 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2168 data for the parameter. Incorporate ABI specifics such as pass-by-
2169 reference and type promotion. */
2172 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2173 struct assign_parm_data_one
*data
)
2175 tree nominal_type
, passed_type
;
2176 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2179 memset (data
, 0, sizeof (*data
));
2181 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2183 data
->named_arg
= 1; /* No variadic parms. */
2184 else if (TREE_CHAIN (parm
))
2185 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2186 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2187 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2189 data
->named_arg
= 0; /* Treat as variadic. */
2191 nominal_type
= TREE_TYPE (parm
);
2192 passed_type
= DECL_ARG_TYPE (parm
);
2194 /* Look out for errors propagating this far. Also, if the parameter's
2195 type is void then its value doesn't matter. */
2196 if (TREE_TYPE (parm
) == error_mark_node
2197 /* This can happen after weird syntax errors
2198 or if an enum type is defined among the parms. */
2199 || TREE_CODE (parm
) != PARM_DECL
2200 || passed_type
== NULL
2201 || VOID_TYPE_P (nominal_type
))
2203 nominal_type
= passed_type
= void_type_node
;
2204 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2208 /* Find mode of arg as it is passed, and mode of arg as it should be
2209 during execution of this function. */
2210 passed_mode
= TYPE_MODE (passed_type
);
2211 nominal_mode
= TYPE_MODE (nominal_type
);
2213 /* If the parm is to be passed as a transparent union, use the type of
2214 the first field for the tests below. We have already verified that
2215 the modes are the same. */
2216 if (TREE_CODE (passed_type
) == UNION_TYPE
2217 && TYPE_TRANSPARENT_UNION (passed_type
))
2218 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2220 /* See if this arg was passed by invisible reference. */
2221 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2222 passed_type
, data
->named_arg
))
2224 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2225 data
->passed_pointer
= true;
2226 passed_mode
= nominal_mode
= Pmode
;
2229 /* Find mode as it is passed by the ABI. */
2230 unsignedp
= TYPE_UNSIGNED (passed_type
);
2231 promoted_mode
= promote_function_mode (passed_type
, passed_mode
, &unsignedp
,
2232 TREE_TYPE (current_function_decl
), 0);
2235 data
->nominal_type
= nominal_type
;
2236 data
->passed_type
= passed_type
;
2237 data
->nominal_mode
= nominal_mode
;
2238 data
->passed_mode
= passed_mode
;
2239 data
->promoted_mode
= promoted_mode
;
2242 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2245 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2246 struct assign_parm_data_one
*data
, bool no_rtl
)
2248 int varargs_pretend_bytes
= 0;
2250 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2251 data
->promoted_mode
,
2253 &varargs_pretend_bytes
, no_rtl
);
2255 /* If the back-end has requested extra stack space, record how much is
2256 needed. Do not change pretend_args_size otherwise since it may be
2257 nonzero from an earlier partial argument. */
2258 if (varargs_pretend_bytes
> 0)
2259 all
->pretend_args_size
= varargs_pretend_bytes
;
2262 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2263 the incoming location of the current parameter. */
2266 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2267 struct assign_parm_data_one
*data
)
2269 HOST_WIDE_INT pretend_bytes
= 0;
2273 if (data
->promoted_mode
== VOIDmode
)
2275 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2279 #ifdef FUNCTION_INCOMING_ARG
2280 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2281 data
->passed_type
, data
->named_arg
);
2283 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2284 data
->passed_type
, data
->named_arg
);
2287 if (entry_parm
== 0)
2288 data
->promoted_mode
= data
->passed_mode
;
2290 /* Determine parm's home in the stack, in case it arrives in the stack
2291 or we should pretend it did. Compute the stack position and rtx where
2292 the argument arrives and its size.
2294 There is one complexity here: If this was a parameter that would
2295 have been passed in registers, but wasn't only because it is
2296 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2297 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2298 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2299 as it was the previous time. */
2300 in_regs
= entry_parm
!= 0;
2301 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2304 if (!in_regs
&& !data
->named_arg
)
2306 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2309 #ifdef FUNCTION_INCOMING_ARG
2310 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2311 data
->passed_type
, true);
2313 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2314 data
->passed_type
, true);
2316 in_regs
= tem
!= NULL
;
2320 /* If this parameter was passed both in registers and in the stack, use
2321 the copy on the stack. */
2322 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2330 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2331 data
->promoted_mode
,
2334 data
->partial
= partial
;
2336 /* The caller might already have allocated stack space for the
2337 register parameters. */
2338 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2340 /* Part of this argument is passed in registers and part
2341 is passed on the stack. Ask the prologue code to extend
2342 the stack part so that we can recreate the full value.
2344 PRETEND_BYTES is the size of the registers we need to store.
2345 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2346 stack space that the prologue should allocate.
2348 Internally, gcc assumes that the argument pointer is aligned
2349 to STACK_BOUNDARY bits. This is used both for alignment
2350 optimizations (see init_emit) and to locate arguments that are
2351 aligned to more than PARM_BOUNDARY bits. We must preserve this
2352 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2353 a stack boundary. */
2355 /* We assume at most one partial arg, and it must be the first
2356 argument on the stack. */
2357 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2359 pretend_bytes
= partial
;
2360 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2362 /* We want to align relative to the actual stack pointer, so
2363 don't include this in the stack size until later. */
2364 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2368 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2369 entry_parm
? data
->partial
: 0, current_function_decl
,
2370 &all
->stack_args_size
, &data
->locate
);
2372 /* Update parm_stack_boundary if this parameter is passed in the
2374 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2375 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2377 /* Adjust offsets to include the pretend args. */
2378 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2379 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2380 data
->locate
.offset
.constant
+= pretend_bytes
;
2382 data
->entry_parm
= entry_parm
;
2385 /* A subroutine of assign_parms. If there is actually space on the stack
2386 for this parm, count it in stack_args_size and return true. */
2389 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2390 struct assign_parm_data_one
*data
)
2392 /* Trivially true if we've no incoming register. */
2393 if (data
->entry_parm
== NULL
)
2395 /* Also true if we're partially in registers and partially not,
2396 since we've arranged to drop the entire argument on the stack. */
2397 else if (data
->partial
!= 0)
2399 /* Also true if the target says that it's passed in both registers
2400 and on the stack. */
2401 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2402 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2404 /* Also true if the target says that there's stack allocated for
2405 all register parameters. */
2406 else if (all
->reg_parm_stack_space
> 0)
2408 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2412 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2413 if (data
->locate
.size
.var
)
2414 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2419 /* A subroutine of assign_parms. Given that this parameter is allocated
2420 stack space by the ABI, find it. */
2423 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2425 rtx offset_rtx
, stack_parm
;
2426 unsigned int align
, boundary
;
2428 /* If we're passing this arg using a reg, make its stack home the
2429 aligned stack slot. */
2430 if (data
->entry_parm
)
2431 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2433 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2435 stack_parm
= crtl
->args
.internal_arg_pointer
;
2436 if (offset_rtx
!= const0_rtx
)
2437 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2438 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2440 if (!data
->passed_pointer
)
2442 set_mem_attributes (stack_parm
, parm
, 1);
2443 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2444 while promoted mode's size is needed. */
2445 if (data
->promoted_mode
!= BLKmode
2446 && data
->promoted_mode
!= DECL_MODE (parm
))
2448 set_mem_size (stack_parm
,
2449 GEN_INT (GET_MODE_SIZE (data
->promoted_mode
)));
2450 if (MEM_EXPR (stack_parm
) && MEM_OFFSET (stack_parm
))
2452 int offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2453 data
->promoted_mode
);
2455 set_mem_offset (stack_parm
,
2456 plus_constant (MEM_OFFSET (stack_parm
),
2462 boundary
= data
->locate
.boundary
;
2463 align
= BITS_PER_UNIT
;
2465 /* If we're padding upward, we know that the alignment of the slot
2466 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2467 intentionally forcing upward padding. Otherwise we have to come
2468 up with a guess at the alignment based on OFFSET_RTX. */
2469 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2471 else if (CONST_INT_P (offset_rtx
))
2473 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2474 align
= align
& -align
;
2476 set_mem_align (stack_parm
, align
);
2478 if (data
->entry_parm
)
2479 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2481 data
->stack_parm
= stack_parm
;
2484 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2485 always valid and contiguous. */
2488 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2490 rtx entry_parm
= data
->entry_parm
;
2491 rtx stack_parm
= data
->stack_parm
;
2493 /* If this parm was passed part in regs and part in memory, pretend it
2494 arrived entirely in memory by pushing the register-part onto the stack.
2495 In the special case of a DImode or DFmode that is split, we could put
2496 it together in a pseudoreg directly, but for now that's not worth
2498 if (data
->partial
!= 0)
2500 /* Handle calls that pass values in multiple non-contiguous
2501 locations. The Irix 6 ABI has examples of this. */
2502 if (GET_CODE (entry_parm
) == PARALLEL
)
2503 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2505 int_size_in_bytes (data
->passed_type
));
2508 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2509 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2510 data
->partial
/ UNITS_PER_WORD
);
2513 entry_parm
= stack_parm
;
2516 /* If we didn't decide this parm came in a register, by default it came
2518 else if (entry_parm
== NULL
)
2519 entry_parm
= stack_parm
;
2521 /* When an argument is passed in multiple locations, we can't make use
2522 of this information, but we can save some copying if the whole argument
2523 is passed in a single register. */
2524 else if (GET_CODE (entry_parm
) == PARALLEL
2525 && data
->nominal_mode
!= BLKmode
2526 && data
->passed_mode
!= BLKmode
)
2528 size_t i
, len
= XVECLEN (entry_parm
, 0);
2530 for (i
= 0; i
< len
; i
++)
2531 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2532 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2533 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2534 == data
->passed_mode
)
2535 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2537 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2542 data
->entry_parm
= entry_parm
;
2545 /* A subroutine of assign_parms. Reconstitute any values which were
2546 passed in multiple registers and would fit in a single register. */
2549 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2551 rtx entry_parm
= data
->entry_parm
;
2553 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2554 This can be done with register operations rather than on the
2555 stack, even if we will store the reconstituted parameter on the
2557 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2559 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2560 emit_group_store (parmreg
, entry_parm
, data
->passed_type
,
2561 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2562 entry_parm
= parmreg
;
2565 data
->entry_parm
= entry_parm
;
2568 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2569 always valid and properly aligned. */
2572 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2574 rtx stack_parm
= data
->stack_parm
;
2576 /* If we can't trust the parm stack slot to be aligned enough for its
2577 ultimate type, don't use that slot after entry. We'll make another
2578 stack slot, if we need one. */
2580 && ((STRICT_ALIGNMENT
2581 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2582 || (data
->nominal_type
2583 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2584 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2587 /* If parm was passed in memory, and we need to convert it on entry,
2588 don't store it back in that same slot. */
2589 else if (data
->entry_parm
== stack_parm
2590 && data
->nominal_mode
!= BLKmode
2591 && data
->nominal_mode
!= data
->passed_mode
)
2594 /* If stack protection is in effect for this function, don't leave any
2595 pointers in their passed stack slots. */
2596 else if (crtl
->stack_protect_guard
2597 && (flag_stack_protect
== 2
2598 || data
->passed_pointer
2599 || POINTER_TYPE_P (data
->nominal_type
)))
2602 data
->stack_parm
= stack_parm
;
2605 /* A subroutine of assign_parms. Return true if the current parameter
2606 should be stored as a BLKmode in the current frame. */
2609 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2611 if (data
->nominal_mode
== BLKmode
)
2613 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2616 #ifdef BLOCK_REG_PADDING
2617 /* Only assign_parm_setup_block knows how to deal with register arguments
2618 that are padded at the least significant end. */
2619 if (REG_P (data
->entry_parm
)
2620 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2621 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2622 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2629 /* A subroutine of assign_parms. Arrange for the parameter to be
2630 present and valid in DATA->STACK_RTL. */
2633 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2634 tree parm
, struct assign_parm_data_one
*data
)
2636 rtx entry_parm
= data
->entry_parm
;
2637 rtx stack_parm
= data
->stack_parm
;
2639 HOST_WIDE_INT size_stored
;
2641 if (GET_CODE (entry_parm
) == PARALLEL
)
2642 entry_parm
= emit_group_move_into_temps (entry_parm
);
2644 size
= int_size_in_bytes (data
->passed_type
);
2645 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2646 if (stack_parm
== 0)
2648 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2649 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2651 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2652 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2653 set_mem_attributes (stack_parm
, parm
, 1);
2656 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2657 calls that pass values in multiple non-contiguous locations. */
2658 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2662 /* Note that we will be storing an integral number of words.
2663 So we have to be careful to ensure that we allocate an
2664 integral number of words. We do this above when we call
2665 assign_stack_local if space was not allocated in the argument
2666 list. If it was, this will not work if PARM_BOUNDARY is not
2667 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2668 if it becomes a problem. Exception is when BLKmode arrives
2669 with arguments not conforming to word_mode. */
2671 if (data
->stack_parm
== 0)
2673 else if (GET_CODE (entry_parm
) == PARALLEL
)
2676 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2678 mem
= validize_mem (stack_parm
);
2680 /* Handle values in multiple non-contiguous locations. */
2681 if (GET_CODE (entry_parm
) == PARALLEL
)
2683 push_to_sequence2 (all
->first_conversion_insn
,
2684 all
->last_conversion_insn
);
2685 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2686 all
->first_conversion_insn
= get_insns ();
2687 all
->last_conversion_insn
= get_last_insn ();
2694 /* If SIZE is that of a mode no bigger than a word, just use
2695 that mode's store operation. */
2696 else if (size
<= UNITS_PER_WORD
)
2698 enum machine_mode mode
2699 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2702 #ifdef BLOCK_REG_PADDING
2703 && (size
== UNITS_PER_WORD
2704 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2705 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2711 /* We are really truncating a word_mode value containing
2712 SIZE bytes into a value of mode MODE. If such an
2713 operation requires no actual instructions, we can refer
2714 to the value directly in mode MODE, otherwise we must
2715 start with the register in word_mode and explicitly
2717 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2718 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2721 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2722 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2724 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2727 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2728 machine must be aligned to the left before storing
2729 to memory. Note that the previous test doesn't
2730 handle all cases (e.g. SIZE == 3). */
2731 else if (size
!= UNITS_PER_WORD
2732 #ifdef BLOCK_REG_PADDING
2733 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2741 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2742 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2744 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2745 build_int_cst (NULL_TREE
, by
),
2747 tem
= change_address (mem
, word_mode
, 0);
2748 emit_move_insn (tem
, x
);
2751 move_block_from_reg (REGNO (entry_parm
), mem
,
2752 size_stored
/ UNITS_PER_WORD
);
2755 move_block_from_reg (REGNO (entry_parm
), mem
,
2756 size_stored
/ UNITS_PER_WORD
);
2758 else if (data
->stack_parm
== 0)
2760 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2761 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2763 all
->first_conversion_insn
= get_insns ();
2764 all
->last_conversion_insn
= get_last_insn ();
2768 data
->stack_parm
= stack_parm
;
2769 SET_DECL_RTL (parm
, stack_parm
);
2772 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2773 parameter. Get it there. Perform all ABI specified conversions. */
2776 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2777 struct assign_parm_data_one
*data
)
2780 enum machine_mode promoted_nominal_mode
;
2781 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2782 bool did_conversion
= false;
2784 /* Store the parm in a pseudoregister during the function, but we may
2785 need to do it in a wider mode. Using 2 here makes the result
2786 consistent with promote_decl_mode and thus expand_expr_real_1. */
2787 promoted_nominal_mode
2788 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
2789 TREE_TYPE (current_function_decl
), 2);
2791 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2793 if (!DECL_ARTIFICIAL (parm
))
2794 mark_user_reg (parmreg
);
2796 /* If this was an item that we received a pointer to,
2797 set DECL_RTL appropriately. */
2798 if (data
->passed_pointer
)
2800 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2801 set_mem_attributes (x
, parm
, 1);
2802 SET_DECL_RTL (parm
, x
);
2805 SET_DECL_RTL (parm
, parmreg
);
2807 assign_parm_remove_parallels (data
);
2809 /* Copy the value into the register, thus bridging between
2810 assign_parm_find_data_types and expand_expr_real_1. */
2811 if (data
->nominal_mode
!= data
->passed_mode
2812 || promoted_nominal_mode
!= data
->promoted_mode
)
2816 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2817 mode, by the caller. We now have to convert it to
2818 NOMINAL_MODE, if different. However, PARMREG may be in
2819 a different mode than NOMINAL_MODE if it is being stored
2822 If ENTRY_PARM is a hard register, it might be in a register
2823 not valid for operating in its mode (e.g., an odd-numbered
2824 register for a DFmode). In that case, moves are the only
2825 thing valid, so we can't do a convert from there. This
2826 occurs when the calling sequence allow such misaligned
2829 In addition, the conversion may involve a call, which could
2830 clobber parameters which haven't been copied to pseudo
2831 registers yet. Therefore, we must first copy the parm to
2832 a pseudo reg here, and save the conversion until after all
2833 parameters have been moved. */
2835 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2837 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2839 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2840 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2842 if (GET_CODE (tempreg
) == SUBREG
2843 && GET_MODE (tempreg
) == data
->nominal_mode
2844 && REG_P (SUBREG_REG (tempreg
))
2845 && data
->nominal_mode
== data
->passed_mode
2846 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2847 && GET_MODE_SIZE (GET_MODE (tempreg
))
2848 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2850 /* The argument is already sign/zero extended, so note it
2852 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2853 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2856 /* TREE_USED gets set erroneously during expand_assignment. */
2857 save_tree_used
= TREE_USED (parm
);
2858 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2859 TREE_USED (parm
) = save_tree_used
;
2860 all
->first_conversion_insn
= get_insns ();
2861 all
->last_conversion_insn
= get_last_insn ();
2864 did_conversion
= true;
2867 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2869 /* If we were passed a pointer but the actual value can safely live
2870 in a register, put it in one. */
2871 if (data
->passed_pointer
2872 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2873 /* If by-reference argument was promoted, demote it. */
2874 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2875 || use_register_for_decl (parm
)))
2877 /* We can't use nominal_mode, because it will have been set to
2878 Pmode above. We must use the actual mode of the parm. */
2879 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2880 mark_user_reg (parmreg
);
2882 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2884 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2885 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2887 push_to_sequence2 (all
->first_conversion_insn
,
2888 all
->last_conversion_insn
);
2889 emit_move_insn (tempreg
, DECL_RTL (parm
));
2890 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2891 emit_move_insn (parmreg
, tempreg
);
2892 all
->first_conversion_insn
= get_insns ();
2893 all
->last_conversion_insn
= get_last_insn ();
2896 did_conversion
= true;
2899 emit_move_insn (parmreg
, DECL_RTL (parm
));
2901 SET_DECL_RTL (parm
, parmreg
);
2903 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2905 data
->stack_parm
= NULL
;
2908 /* Mark the register as eliminable if we did no conversion and it was
2909 copied from memory at a fixed offset, and the arg pointer was not
2910 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2911 offset formed an invalid address, such memory-equivalences as we
2912 make here would screw up life analysis for it. */
2913 if (data
->nominal_mode
== data
->passed_mode
2915 && data
->stack_parm
!= 0
2916 && MEM_P (data
->stack_parm
)
2917 && data
->locate
.offset
.var
== 0
2918 && reg_mentioned_p (virtual_incoming_args_rtx
,
2919 XEXP (data
->stack_parm
, 0)))
2921 rtx linsn
= get_last_insn ();
2924 /* Mark complex types separately. */
2925 if (GET_CODE (parmreg
) == CONCAT
)
2927 enum machine_mode submode
2928 = GET_MODE_INNER (GET_MODE (parmreg
));
2929 int regnor
= REGNO (XEXP (parmreg
, 0));
2930 int regnoi
= REGNO (XEXP (parmreg
, 1));
2931 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2932 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2933 GET_MODE_SIZE (submode
));
2935 /* Scan backwards for the set of the real and
2937 for (sinsn
= linsn
; sinsn
!= 0;
2938 sinsn
= prev_nonnote_insn (sinsn
))
2940 set
= single_set (sinsn
);
2944 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2945 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2946 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2947 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2950 else if ((set
= single_set (linsn
)) != 0
2951 && SET_DEST (set
) == parmreg
)
2952 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2955 /* For pointer data type, suggest pointer register. */
2956 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2957 mark_reg_pointer (parmreg
,
2958 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2961 /* A subroutine of assign_parms. Allocate stack space to hold the current
2962 parameter. Get it there. Perform all ABI specified conversions. */
2965 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2966 struct assign_parm_data_one
*data
)
2968 /* Value must be stored in the stack slot STACK_PARM during function
2970 bool to_conversion
= false;
2972 assign_parm_remove_parallels (data
);
2974 if (data
->promoted_mode
!= data
->nominal_mode
)
2976 /* Conversion is required. */
2977 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2979 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2981 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2982 to_conversion
= true;
2984 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2985 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2987 if (data
->stack_parm
)
2989 int offset
= subreg_lowpart_offset (data
->nominal_mode
,
2990 GET_MODE (data
->stack_parm
));
2991 /* ??? This may need a big-endian conversion on sparc64. */
2993 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2994 if (offset
&& MEM_OFFSET (data
->stack_parm
))
2995 set_mem_offset (data
->stack_parm
,
2996 plus_constant (MEM_OFFSET (data
->stack_parm
),
3001 if (data
->entry_parm
!= data
->stack_parm
)
3005 if (data
->stack_parm
== 0)
3007 int align
= STACK_SLOT_ALIGNMENT (data
->passed_type
,
3008 GET_MODE (data
->entry_parm
),
3009 TYPE_ALIGN (data
->passed_type
));
3011 = assign_stack_local (GET_MODE (data
->entry_parm
),
3012 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3014 set_mem_attributes (data
->stack_parm
, parm
, 1);
3017 dest
= validize_mem (data
->stack_parm
);
3018 src
= validize_mem (data
->entry_parm
);
3022 /* Use a block move to handle potentially misaligned entry_parm. */
3024 push_to_sequence2 (all
->first_conversion_insn
,
3025 all
->last_conversion_insn
);
3026 to_conversion
= true;
3028 emit_block_move (dest
, src
,
3029 GEN_INT (int_size_in_bytes (data
->passed_type
)),
3033 emit_move_insn (dest
, src
);
3038 all
->first_conversion_insn
= get_insns ();
3039 all
->last_conversion_insn
= get_last_insn ();
3043 SET_DECL_RTL (parm
, data
->stack_parm
);
3046 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3047 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3050 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
3053 tree orig_fnargs
= all
->orig_fnargs
;
3055 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3057 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3058 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3060 rtx tmp
, real
, imag
;
3061 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3063 real
= DECL_RTL (fnargs
);
3064 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
3065 if (inner
!= GET_MODE (real
))
3067 real
= gen_lowpart_SUBREG (inner
, real
);
3068 imag
= gen_lowpart_SUBREG (inner
, imag
);
3071 if (TREE_ADDRESSABLE (parm
))
3074 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3075 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3077 TYPE_ALIGN (TREE_TYPE (parm
)));
3079 /* split_complex_arg put the real and imag parts in
3080 pseudos. Move them to memory. */
3081 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3082 set_mem_attributes (tmp
, parm
, 1);
3083 rmem
= adjust_address_nv (tmp
, inner
, 0);
3084 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3085 push_to_sequence2 (all
->first_conversion_insn
,
3086 all
->last_conversion_insn
);
3087 emit_move_insn (rmem
, real
);
3088 emit_move_insn (imem
, imag
);
3089 all
->first_conversion_insn
= get_insns ();
3090 all
->last_conversion_insn
= get_last_insn ();
3094 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3095 SET_DECL_RTL (parm
, tmp
);
3097 real
= DECL_INCOMING_RTL (fnargs
);
3098 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
3099 if (inner
!= GET_MODE (real
))
3101 real
= gen_lowpart_SUBREG (inner
, real
);
3102 imag
= gen_lowpart_SUBREG (inner
, imag
);
3104 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3105 set_decl_incoming_rtl (parm
, tmp
, false);
3106 fnargs
= TREE_CHAIN (fnargs
);
3110 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
3111 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
3113 /* Set MEM_EXPR to the original decl, i.e. to PARM,
3114 instead of the copy of decl, i.e. FNARGS. */
3115 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
3116 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
3119 fnargs
= TREE_CHAIN (fnargs
);
3123 /* Assign RTL expressions to the function's parameters. This may involve
3124 copying them into registers and using those registers as the DECL_RTL. */
3127 assign_parms (tree fndecl
)
3129 struct assign_parm_data_all all
;
3132 crtl
->args
.internal_arg_pointer
3133 = targetm
.calls
.internal_arg_pointer ();
3135 assign_parms_initialize_all (&all
);
3136 fnargs
= assign_parms_augmented_arg_list (&all
);
3138 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3140 struct assign_parm_data_one data
;
3142 /* Extract the type of PARM; adjust it according to ABI. */
3143 assign_parm_find_data_types (&all
, parm
, &data
);
3145 /* Early out for errors and void parameters. */
3146 if (data
.passed_mode
== VOIDmode
)
3148 SET_DECL_RTL (parm
, const0_rtx
);
3149 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3153 /* Estimate stack alignment from parameter alignment. */
3154 if (SUPPORTS_STACK_ALIGNMENT
)
3156 unsigned int align
= FUNCTION_ARG_BOUNDARY (data
.promoted_mode
,
3158 align
= MINIMUM_ALIGNMENT (data
.passed_type
, data
.promoted_mode
,
3160 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3161 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3162 TYPE_MODE (data
.nominal_type
),
3163 TYPE_ALIGN (data
.nominal_type
));
3164 if (crtl
->stack_alignment_estimated
< align
)
3166 gcc_assert (!crtl
->stack_realign_processed
);
3167 crtl
->stack_alignment_estimated
= align
;
3171 if (cfun
->stdarg
&& !TREE_CHAIN (parm
))
3172 assign_parms_setup_varargs (&all
, &data
, false);
3174 /* Find out where the parameter arrives in this function. */
3175 assign_parm_find_entry_rtl (&all
, &data
);
3177 /* Find out where stack space for this parameter might be. */
3178 if (assign_parm_is_stack_parm (&all
, &data
))
3180 assign_parm_find_stack_rtl (parm
, &data
);
3181 assign_parm_adjust_entry_rtl (&data
);
3184 /* Record permanently how this parm was passed. */
3185 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
3187 /* Update info on where next arg arrives in registers. */
3188 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3189 data
.passed_type
, data
.named_arg
);
3191 assign_parm_adjust_stack_rtl (&data
);
3193 if (assign_parm_setup_block_p (&data
))
3194 assign_parm_setup_block (&all
, parm
, &data
);
3195 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3196 assign_parm_setup_reg (&all
, parm
, &data
);
3198 assign_parm_setup_stack (&all
, parm
, &data
);
3201 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
3202 assign_parms_unsplit_complex (&all
, fnargs
);
3204 /* Output all parameter conversion instructions (possibly including calls)
3205 now that all parameters have been copied out of hard registers. */
3206 emit_insn (all
.first_conversion_insn
);
3208 /* Estimate reload stack alignment from scalar return mode. */
3209 if (SUPPORTS_STACK_ALIGNMENT
)
3211 if (DECL_RESULT (fndecl
))
3213 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3214 enum machine_mode mode
= TYPE_MODE (type
);
3218 && !AGGREGATE_TYPE_P (type
))
3220 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3221 if (crtl
->stack_alignment_estimated
< align
)
3223 gcc_assert (!crtl
->stack_realign_processed
);
3224 crtl
->stack_alignment_estimated
= align
;
3230 /* If we are receiving a struct value address as the first argument, set up
3231 the RTL for the function result. As this might require code to convert
3232 the transmitted address to Pmode, we do this here to ensure that possible
3233 preliminary conversions of the address have been emitted already. */
3234 if (all
.function_result_decl
)
3236 tree result
= DECL_RESULT (current_function_decl
);
3237 rtx addr
= DECL_RTL (all
.function_result_decl
);
3240 if (DECL_BY_REFERENCE (result
))
3244 addr
= convert_memory_address (Pmode
, addr
);
3245 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3246 set_mem_attributes (x
, result
, 1);
3248 SET_DECL_RTL (result
, x
);
3251 /* We have aligned all the args, so add space for the pretend args. */
3252 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3253 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3254 crtl
->args
.size
= all
.stack_args_size
.constant
;
3256 /* Adjust function incoming argument size for alignment and
3259 #ifdef REG_PARM_STACK_SPACE
3260 crtl
->args
.size
= MAX (crtl
->args
.size
,
3261 REG_PARM_STACK_SPACE (fndecl
));
3264 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3265 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3267 #ifdef ARGS_GROW_DOWNWARD
3268 crtl
->args
.arg_offset_rtx
3269 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3270 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3271 size_int (-all
.stack_args_size
.constant
)),
3272 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3274 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3277 /* See how many bytes, if any, of its args a function should try to pop
3280 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3283 /* For stdarg.h function, save info about
3284 regs and stack space used by the named args. */
3286 crtl
->args
.info
= all
.args_so_far
;
3288 /* Set the rtx used for the function return value. Put this in its
3289 own variable so any optimizers that need this information don't have
3290 to include tree.h. Do this here so it gets done when an inlined
3291 function gets output. */
3294 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3295 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3297 /* If scalar return value was computed in a pseudo-reg, or was a named
3298 return value that got dumped to the stack, copy that to the hard
3300 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3302 tree decl_result
= DECL_RESULT (fndecl
);
3303 rtx decl_rtl
= DECL_RTL (decl_result
);
3305 if (REG_P (decl_rtl
)
3306 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3307 : DECL_REGISTER (decl_result
))
3311 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3313 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3314 /* The delay slot scheduler assumes that crtl->return_rtx
3315 holds the hard register containing the return value, not a
3316 temporary pseudo. */
3317 crtl
->return_rtx
= real_decl_rtl
;
3322 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3323 For all seen types, gimplify their sizes. */
3326 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3333 if (POINTER_TYPE_P (t
))
3335 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3336 && !TYPE_SIZES_GIMPLIFIED (t
))
3338 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3346 /* Gimplify the parameter list for current_function_decl. This involves
3347 evaluating SAVE_EXPRs of variable sized parameters and generating code
3348 to implement callee-copies reference parameters. Returns a sequence of
3349 statements to add to the beginning of the function. */
3352 gimplify_parameters (void)
3354 struct assign_parm_data_all all
;
3356 gimple_seq stmts
= NULL
;
3358 assign_parms_initialize_all (&all
);
3359 fnargs
= assign_parms_augmented_arg_list (&all
);
3361 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3363 struct assign_parm_data_one data
;
3365 /* Extract the type of PARM; adjust it according to ABI. */
3366 assign_parm_find_data_types (&all
, parm
, &data
);
3368 /* Early out for errors and void parameters. */
3369 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3372 /* Update info on where next arg arrives in registers. */
3373 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3374 data
.passed_type
, data
.named_arg
);
3376 /* ??? Once upon a time variable_size stuffed parameter list
3377 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3378 turned out to be less than manageable in the gimple world.
3379 Now we have to hunt them down ourselves. */
3380 walk_tree_without_duplicates (&data
.passed_type
,
3381 gimplify_parm_type
, &stmts
);
3383 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3385 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3386 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3389 if (data
.passed_pointer
)
3391 tree type
= TREE_TYPE (data
.passed_type
);
3392 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3393 type
, data
.named_arg
))
3397 /* For constant-sized objects, this is trivial; for
3398 variable-sized objects, we have to play games. */
3399 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3400 && !(flag_stack_check
== GENERIC_STACK_CHECK
3401 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3402 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3404 local
= create_tmp_var (type
, get_name (parm
));
3405 DECL_IGNORED_P (local
) = 0;
3406 /* If PARM was addressable, move that flag over
3407 to the local copy, as its address will be taken,
3409 if (TREE_ADDRESSABLE (parm
))
3411 TREE_ADDRESSABLE (parm
) = 0;
3412 TREE_ADDRESSABLE (local
) = 1;
3417 tree ptr_type
, addr
;
3419 ptr_type
= build_pointer_type (type
);
3420 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3421 DECL_IGNORED_P (addr
) = 0;
3422 local
= build_fold_indirect_ref (addr
);
3424 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3425 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3426 t
= fold_convert (ptr_type
, t
);
3427 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3428 gimplify_and_add (t
, &stmts
);
3431 gimplify_assign (local
, parm
, &stmts
);
3433 SET_DECL_VALUE_EXPR (parm
, local
);
3434 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3442 /* Compute the size and offset from the start of the stacked arguments for a
3443 parm passed in mode PASSED_MODE and with type TYPE.
3445 INITIAL_OFFSET_PTR points to the current offset into the stacked
3448 The starting offset and size for this parm are returned in
3449 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3450 nonzero, the offset is that of stack slot, which is returned in
3451 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3452 padding required from the initial offset ptr to the stack slot.
3454 IN_REGS is nonzero if the argument will be passed in registers. It will
3455 never be set if REG_PARM_STACK_SPACE is not defined.
3457 FNDECL is the function in which the argument was defined.
3459 There are two types of rounding that are done. The first, controlled by
3460 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3461 list to be aligned to the specific boundary (in bits). This rounding
3462 affects the initial and starting offsets, but not the argument size.
3464 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3465 optionally rounds the size of the parm to PARM_BOUNDARY. The
3466 initial offset is not affected by this rounding, while the size always
3467 is and the starting offset may be. */
3469 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3470 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3471 callers pass in the total size of args so far as
3472 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3475 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3476 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3477 struct args_size
*initial_offset_ptr
,
3478 struct locate_and_pad_arg_data
*locate
)
3481 enum direction where_pad
;
3482 unsigned int boundary
;
3483 int reg_parm_stack_space
= 0;
3484 int part_size_in_regs
;
3486 #ifdef REG_PARM_STACK_SPACE
3487 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3489 /* If we have found a stack parm before we reach the end of the
3490 area reserved for registers, skip that area. */
3493 if (reg_parm_stack_space
> 0)
3495 if (initial_offset_ptr
->var
)
3497 initial_offset_ptr
->var
3498 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3499 ssize_int (reg_parm_stack_space
));
3500 initial_offset_ptr
->constant
= 0;
3502 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3503 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3506 #endif /* REG_PARM_STACK_SPACE */
3508 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3511 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3512 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3513 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3514 locate
->where_pad
= where_pad
;
3516 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3517 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3518 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3520 locate
->boundary
= boundary
;
3522 if (SUPPORTS_STACK_ALIGNMENT
)
3524 /* stack_alignment_estimated can't change after stack has been
3526 if (crtl
->stack_alignment_estimated
< boundary
)
3528 if (!crtl
->stack_realign_processed
)
3529 crtl
->stack_alignment_estimated
= boundary
;
3532 /* If stack is realigned and stack alignment value
3533 hasn't been finalized, it is OK not to increase
3534 stack_alignment_estimated. The bigger alignment
3535 requirement is recorded in stack_alignment_needed
3537 gcc_assert (!crtl
->stack_realign_finalized
3538 && crtl
->stack_realign_needed
);
3543 /* Remember if the outgoing parameter requires extra alignment on the
3544 calling function side. */
3545 if (crtl
->stack_alignment_needed
< boundary
)
3546 crtl
->stack_alignment_needed
= boundary
;
3547 if (crtl
->preferred_stack_boundary
< boundary
)
3548 crtl
->preferred_stack_boundary
= boundary
;
3550 #ifdef ARGS_GROW_DOWNWARD
3551 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3552 if (initial_offset_ptr
->var
)
3553 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3554 initial_offset_ptr
->var
);
3558 if (where_pad
!= none
3559 && (!host_integerp (sizetree
, 1)
3560 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3561 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3562 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3565 locate
->slot_offset
.constant
+= part_size_in_regs
;
3568 #ifdef REG_PARM_STACK_SPACE
3569 || REG_PARM_STACK_SPACE (fndecl
) > 0
3572 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3573 &locate
->alignment_pad
);
3575 locate
->size
.constant
= (-initial_offset_ptr
->constant
3576 - locate
->slot_offset
.constant
);
3577 if (initial_offset_ptr
->var
)
3578 locate
->size
.var
= size_binop (MINUS_EXPR
,
3579 size_binop (MINUS_EXPR
,
3581 initial_offset_ptr
->var
),
3582 locate
->slot_offset
.var
);
3584 /* Pad_below needs the pre-rounded size to know how much to pad
3586 locate
->offset
= locate
->slot_offset
;
3587 if (where_pad
== downward
)
3588 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3590 #else /* !ARGS_GROW_DOWNWARD */
3592 #ifdef REG_PARM_STACK_SPACE
3593 || REG_PARM_STACK_SPACE (fndecl
) > 0
3596 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3597 &locate
->alignment_pad
);
3598 locate
->slot_offset
= *initial_offset_ptr
;
3600 #ifdef PUSH_ROUNDING
3601 if (passed_mode
!= BLKmode
)
3602 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3605 /* Pad_below needs the pre-rounded size to know how much to pad below
3606 so this must be done before rounding up. */
3607 locate
->offset
= locate
->slot_offset
;
3608 if (where_pad
== downward
)
3609 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3611 if (where_pad
!= none
3612 && (!host_integerp (sizetree
, 1)
3613 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3614 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3616 ADD_PARM_SIZE (locate
->size
, sizetree
);
3618 locate
->size
.constant
-= part_size_in_regs
;
3619 #endif /* ARGS_GROW_DOWNWARD */
3621 #ifdef FUNCTION_ARG_OFFSET
3622 locate
->offset
.constant
+= FUNCTION_ARG_OFFSET (passed_mode
, type
);
3626 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3627 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3630 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3631 struct args_size
*alignment_pad
)
3633 tree save_var
= NULL_TREE
;
3634 HOST_WIDE_INT save_constant
= 0;
3635 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3636 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3638 #ifdef SPARC_STACK_BOUNDARY_HACK
3639 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3640 the real alignment of %sp. However, when it does this, the
3641 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3642 if (SPARC_STACK_BOUNDARY_HACK
)
3646 if (boundary
> PARM_BOUNDARY
)
3648 save_var
= offset_ptr
->var
;
3649 save_constant
= offset_ptr
->constant
;
3652 alignment_pad
->var
= NULL_TREE
;
3653 alignment_pad
->constant
= 0;
3655 if (boundary
> BITS_PER_UNIT
)
3657 if (offset_ptr
->var
)
3659 tree sp_offset_tree
= ssize_int (sp_offset
);
3660 tree offset
= size_binop (PLUS_EXPR
,
3661 ARGS_SIZE_TREE (*offset_ptr
),
3663 #ifdef ARGS_GROW_DOWNWARD
3664 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3666 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3669 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3670 /* ARGS_SIZE_TREE includes constant term. */
3671 offset_ptr
->constant
= 0;
3672 if (boundary
> PARM_BOUNDARY
)
3673 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3678 offset_ptr
->constant
= -sp_offset
+
3679 #ifdef ARGS_GROW_DOWNWARD
3680 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3682 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3684 if (boundary
> PARM_BOUNDARY
)
3685 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3691 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3693 if (passed_mode
!= BLKmode
)
3695 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3696 offset_ptr
->constant
3697 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3698 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3699 - GET_MODE_SIZE (passed_mode
));
3703 if (TREE_CODE (sizetree
) != INTEGER_CST
3704 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3706 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3707 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3709 ADD_PARM_SIZE (*offset_ptr
, s2
);
3710 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3716 /* True if register REGNO was alive at a place where `setjmp' was
3717 called and was set more than once or is an argument. Such regs may
3718 be clobbered by `longjmp'. */
3721 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3723 /* There appear to be cases where some local vars never reach the
3724 backend but have bogus regnos. */
3725 if (regno
>= max_reg_num ())
3728 return ((REG_N_SETS (regno
) > 1
3729 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3730 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3733 /* Walk the tree of blocks describing the binding levels within a
3734 function and warn about variables the might be killed by setjmp or
3735 vfork. This is done after calling flow_analysis before register
3736 allocation since that will clobber the pseudo-regs to hard
3740 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3744 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3746 if (TREE_CODE (decl
) == VAR_DECL
3747 && DECL_RTL_SET_P (decl
)
3748 && REG_P (DECL_RTL (decl
))
3749 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3750 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3751 " %<longjmp%> or %<vfork%>", decl
);
3754 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3755 setjmp_vars_warning (setjmp_crosses
, sub
);
3758 /* Do the appropriate part of setjmp_vars_warning
3759 but for arguments instead of local variables. */
3762 setjmp_args_warning (bitmap setjmp_crosses
)
3765 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3766 decl
; decl
= TREE_CHAIN (decl
))
3767 if (DECL_RTL (decl
) != 0
3768 && REG_P (DECL_RTL (decl
))
3769 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3770 warning (OPT_Wclobbered
,
3771 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3775 /* Generate warning messages for variables live across setjmp. */
3778 generate_setjmp_warnings (void)
3780 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3782 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3783 || bitmap_empty_p (setjmp_crosses
))
3786 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3787 setjmp_args_warning (setjmp_crosses
);
3791 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3792 and create duplicate blocks. */
3793 /* ??? Need an option to either create block fragments or to create
3794 abstract origin duplicates of a source block. It really depends
3795 on what optimization has been performed. */
3798 reorder_blocks (void)
3800 tree block
= DECL_INITIAL (current_function_decl
);
3801 VEC(tree
,heap
) *block_stack
;
3803 if (block
== NULL_TREE
)
3806 block_stack
= VEC_alloc (tree
, heap
, 10);
3808 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3809 clear_block_marks (block
);
3811 /* Prune the old trees away, so that they don't get in the way. */
3812 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3813 BLOCK_CHAIN (block
) = NULL_TREE
;
3815 /* Recreate the block tree from the note nesting. */
3816 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3817 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3819 VEC_free (tree
, heap
, block_stack
);
3822 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3825 clear_block_marks (tree block
)
3829 TREE_ASM_WRITTEN (block
) = 0;
3830 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3831 block
= BLOCK_CHAIN (block
);
3836 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3840 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3844 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3846 tree block
= NOTE_BLOCK (insn
);
3849 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3850 ? BLOCK_FRAGMENT_ORIGIN (block
)
3853 /* If we have seen this block before, that means it now
3854 spans multiple address regions. Create a new fragment. */
3855 if (TREE_ASM_WRITTEN (block
))
3857 tree new_block
= copy_node (block
);
3859 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3860 BLOCK_FRAGMENT_CHAIN (new_block
)
3861 = BLOCK_FRAGMENT_CHAIN (origin
);
3862 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3864 NOTE_BLOCK (insn
) = new_block
;
3868 BLOCK_SUBBLOCKS (block
) = 0;
3869 TREE_ASM_WRITTEN (block
) = 1;
3870 /* When there's only one block for the entire function,
3871 current_block == block and we mustn't do this, it
3872 will cause infinite recursion. */
3873 if (block
!= current_block
)
3875 if (block
!= origin
)
3876 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3878 BLOCK_SUPERCONTEXT (block
) = current_block
;
3879 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3880 BLOCK_SUBBLOCKS (current_block
) = block
;
3881 current_block
= origin
;
3883 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3885 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3887 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3888 BLOCK_SUBBLOCKS (current_block
)
3889 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3890 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3896 /* Reverse the order of elements in the chain T of blocks,
3897 and return the new head of the chain (old last element). */
3900 blocks_nreverse (tree t
)
3902 tree prev
= 0, decl
, next
;
3903 for (decl
= t
; decl
; decl
= next
)
3905 next
= BLOCK_CHAIN (decl
);
3906 BLOCK_CHAIN (decl
) = prev
;
3912 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3913 non-NULL, list them all into VECTOR, in a depth-first preorder
3914 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3918 all_blocks (tree block
, tree
*vector
)
3924 TREE_ASM_WRITTEN (block
) = 0;
3926 /* Record this block. */
3928 vector
[n_blocks
] = block
;
3932 /* Record the subblocks, and their subblocks... */
3933 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3934 vector
? vector
+ n_blocks
: 0);
3935 block
= BLOCK_CHAIN (block
);
3941 /* Return a vector containing all the blocks rooted at BLOCK. The
3942 number of elements in the vector is stored in N_BLOCKS_P. The
3943 vector is dynamically allocated; it is the caller's responsibility
3944 to call `free' on the pointer returned. */
3947 get_block_vector (tree block
, int *n_blocks_p
)
3951 *n_blocks_p
= all_blocks (block
, NULL
);
3952 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3953 all_blocks (block
, block_vector
);
3955 return block_vector
;
3958 static GTY(()) int next_block_index
= 2;
3960 /* Set BLOCK_NUMBER for all the blocks in FN. */
3963 number_blocks (tree fn
)
3969 /* For SDB and XCOFF debugging output, we start numbering the blocks
3970 from 1 within each function, rather than keeping a running
3972 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3973 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3974 next_block_index
= 1;
3977 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3979 /* The top-level BLOCK isn't numbered at all. */
3980 for (i
= 1; i
< n_blocks
; ++i
)
3981 /* We number the blocks from two. */
3982 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3984 free (block_vector
);
3989 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3992 debug_find_var_in_block_tree (tree var
, tree block
)
3996 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4000 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4002 tree ret
= debug_find_var_in_block_tree (var
, t
);
4010 /* Keep track of whether we're in a dummy function context. If we are,
4011 we don't want to invoke the set_current_function hook, because we'll
4012 get into trouble if the hook calls target_reinit () recursively or
4013 when the initial initialization is not yet complete. */
4015 static bool in_dummy_function
;
4017 /* Invoke the target hook when setting cfun. Update the optimization options
4018 if the function uses different options than the default. */
4021 invoke_set_current_function_hook (tree fndecl
)
4023 if (!in_dummy_function
)
4025 tree opts
= ((fndecl
)
4026 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4027 : optimization_default_node
);
4030 opts
= optimization_default_node
;
4032 /* Change optimization options if needed. */
4033 if (optimization_current_node
!= opts
)
4035 optimization_current_node
= opts
;
4036 cl_optimization_restore (TREE_OPTIMIZATION (opts
));
4039 targetm
.set_current_function (fndecl
);
4043 /* cfun should never be set directly; use this function. */
4046 set_cfun (struct function
*new_cfun
)
4048 if (cfun
!= new_cfun
)
4051 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4055 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4057 static VEC(function_p
,heap
) *cfun_stack
;
4059 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4062 push_cfun (struct function
*new_cfun
)
4064 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4065 set_cfun (new_cfun
);
4068 /* Pop cfun from the stack. */
4073 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
4074 set_cfun (new_cfun
);
4077 /* Return value of funcdef and increase it. */
4079 get_next_funcdef_no (void)
4081 return funcdef_no
++;
4084 /* Allocate a function structure for FNDECL and set its contents
4085 to the defaults. Set cfun to the newly-allocated object.
4086 Some of the helper functions invoked during initialization assume
4087 that cfun has already been set. Therefore, assign the new object
4088 directly into cfun and invoke the back end hook explicitly at the
4089 very end, rather than initializing a temporary and calling set_cfun
4092 ABSTRACT_P is true if this is a function that will never be seen by
4093 the middle-end. Such functions are front-end concepts (like C++
4094 function templates) that do not correspond directly to functions
4095 placed in object files. */
4098 allocate_struct_function (tree fndecl
, bool abstract_p
)
4101 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4103 cfun
= GGC_CNEW (struct function
);
4105 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
4107 init_eh_for_function ();
4109 if (init_machine_status
)
4110 cfun
->machine
= (*init_machine_status
) ();
4112 #ifdef OVERRIDE_ABI_FORMAT
4113 OVERRIDE_ABI_FORMAT (fndecl
);
4116 invoke_set_current_function_hook (fndecl
);
4118 if (fndecl
!= NULL_TREE
)
4120 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4121 cfun
->decl
= fndecl
;
4122 current_function_funcdef_no
= get_next_funcdef_no ();
4124 result
= DECL_RESULT (fndecl
);
4125 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4127 #ifdef PCC_STATIC_STRUCT_RETURN
4128 cfun
->returns_pcc_struct
= 1;
4130 cfun
->returns_struct
= 1;
4135 && TYPE_ARG_TYPES (fntype
) != 0
4136 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
4137 != void_type_node
));
4139 /* Assume all registers in stdarg functions need to be saved. */
4140 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4141 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4145 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4146 instead of just setting it. */
4149 push_struct_function (tree fndecl
)
4151 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4152 allocate_struct_function (fndecl
, false);
4155 /* Reset cfun, and other non-struct-function variables to defaults as
4156 appropriate for emitting rtl at the start of a function. */
4159 prepare_function_start (void)
4161 gcc_assert (!crtl
->emit
.x_last_insn
);
4164 init_varasm_status ();
4166 default_rtl_profile ();
4168 cse_not_expected
= ! optimize
;
4170 /* Caller save not needed yet. */
4171 caller_save_needed
= 0;
4173 /* We haven't done register allocation yet. */
4176 /* Indicate that we have not instantiated virtual registers yet. */
4177 virtuals_instantiated
= 0;
4179 /* Indicate that we want CONCATs now. */
4180 generating_concat_p
= 1;
4182 /* Indicate we have no need of a frame pointer yet. */
4183 frame_pointer_needed
= 0;
4186 /* Initialize the rtl expansion mechanism so that we can do simple things
4187 like generate sequences. This is used to provide a context during global
4188 initialization of some passes. You must call expand_dummy_function_end
4189 to exit this context. */
4192 init_dummy_function_start (void)
4194 gcc_assert (!in_dummy_function
);
4195 in_dummy_function
= true;
4196 push_struct_function (NULL_TREE
);
4197 prepare_function_start ();
4200 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4201 and initialize static variables for generating RTL for the statements
4205 init_function_start (tree subr
)
4207 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4208 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4210 allocate_struct_function (subr
, false);
4211 prepare_function_start ();
4213 /* Warn if this value is an aggregate type,
4214 regardless of which calling convention we are using for it. */
4215 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4216 warning (OPT_Waggregate_return
, "function returns an aggregate");
4219 /* Make sure all values used by the optimization passes have sane defaults. */
4221 init_function_for_compilation (void)
4227 struct rtl_opt_pass pass_init_function
=
4233 init_function_for_compilation
, /* execute */
4236 0, /* static_pass_number */
4237 TV_NONE
, /* tv_id */
4238 0, /* properties_required */
4239 0, /* properties_provided */
4240 0, /* properties_destroyed */
4241 0, /* todo_flags_start */
4242 0 /* todo_flags_finish */
4248 expand_main_function (void)
4250 #if (defined(INVOKE__main) \
4251 || (!defined(HAS_INIT_SECTION) \
4252 && !defined(INIT_SECTION_ASM_OP) \
4253 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4254 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4258 /* Expand code to initialize the stack_protect_guard. This is invoked at
4259 the beginning of a function to be protected. */
4261 #ifndef HAVE_stack_protect_set
4262 # define HAVE_stack_protect_set 0
4263 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4267 stack_protect_prologue (void)
4269 tree guard_decl
= targetm
.stack_protect_guard ();
4272 /* Avoid expand_expr here, because we don't want guard_decl pulled
4273 into registers unless absolutely necessary. And we know that
4274 crtl->stack_protect_guard is a local stack slot, so this skips
4276 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4277 y
= validize_mem (DECL_RTL (guard_decl
));
4279 /* Allow the target to copy from Y to X without leaking Y into a
4281 if (HAVE_stack_protect_set
)
4283 rtx insn
= gen_stack_protect_set (x
, y
);
4291 /* Otherwise do a straight move. */
4292 emit_move_insn (x
, y
);
4295 /* Expand code to verify the stack_protect_guard. This is invoked at
4296 the end of a function to be protected. */
4298 #ifndef HAVE_stack_protect_test
4299 # define HAVE_stack_protect_test 0
4300 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4304 stack_protect_epilogue (void)
4306 tree guard_decl
= targetm
.stack_protect_guard ();
4307 rtx label
= gen_label_rtx ();
4310 /* Avoid expand_expr here, because we don't want guard_decl pulled
4311 into registers unless absolutely necessary. And we know that
4312 crtl->stack_protect_guard is a local stack slot, so this skips
4314 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4315 y
= validize_mem (DECL_RTL (guard_decl
));
4317 /* Allow the target to compare Y with X without leaking either into
4319 switch (HAVE_stack_protect_test
!= 0)
4322 tmp
= gen_stack_protect_test (x
, y
, label
);
4331 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4335 /* The noreturn predictor has been moved to the tree level. The rtl-level
4336 predictors estimate this branch about 20%, which isn't enough to get
4337 things moved out of line. Since this is the only extant case of adding
4338 a noreturn function at the rtl level, it doesn't seem worth doing ought
4339 except adding the prediction by hand. */
4340 tmp
= get_last_insn ();
4342 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4344 expand_expr_stmt (targetm
.stack_protect_fail ());
4348 /* Start the RTL for a new function, and set variables used for
4350 SUBR is the FUNCTION_DECL node.
4351 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4352 the function's parameters, which must be run at any return statement. */
4355 expand_function_start (tree subr
)
4357 /* Make sure volatile mem refs aren't considered
4358 valid operands of arithmetic insns. */
4359 init_recog_no_volatile ();
4363 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4366 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4368 /* Make the label for return statements to jump to. Do not special
4369 case machines with special return instructions -- they will be
4370 handled later during jump, ifcvt, or epilogue creation. */
4371 return_label
= gen_label_rtx ();
4373 /* Initialize rtx used to return the value. */
4374 /* Do this before assign_parms so that we copy the struct value address
4375 before any library calls that assign parms might generate. */
4377 /* Decide whether to return the value in memory or in a register. */
4378 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4380 /* Returning something that won't go in a register. */
4381 rtx value_address
= 0;
4383 #ifdef PCC_STATIC_STRUCT_RETURN
4384 if (cfun
->returns_pcc_struct
)
4386 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4387 value_address
= assemble_static_space (size
);
4392 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4393 /* Expect to be passed the address of a place to store the value.
4394 If it is passed as an argument, assign_parms will take care of
4398 value_address
= gen_reg_rtx (Pmode
);
4399 emit_move_insn (value_address
, sv
);
4404 rtx x
= value_address
;
4405 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4407 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4408 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4410 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4413 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4414 /* If return mode is void, this decl rtl should not be used. */
4415 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4418 /* Compute the return values into a pseudo reg, which we will copy
4419 into the true return register after the cleanups are done. */
4420 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4421 if (TYPE_MODE (return_type
) != BLKmode
4422 && targetm
.calls
.return_in_msb (return_type
))
4423 /* expand_function_end will insert the appropriate padding in
4424 this case. Use the return value's natural (unpadded) mode
4425 within the function proper. */
4426 SET_DECL_RTL (DECL_RESULT (subr
),
4427 gen_reg_rtx (TYPE_MODE (return_type
)));
4430 /* In order to figure out what mode to use for the pseudo, we
4431 figure out what the mode of the eventual return register will
4432 actually be, and use that. */
4433 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4435 /* Structures that are returned in registers are not
4436 aggregate_value_p, so we may see a PARALLEL or a REG. */
4437 if (REG_P (hard_reg
))
4438 SET_DECL_RTL (DECL_RESULT (subr
),
4439 gen_reg_rtx (GET_MODE (hard_reg
)));
4442 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4443 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4447 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4448 result to the real return register(s). */
4449 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4452 /* Initialize rtx for parameters and local variables.
4453 In some cases this requires emitting insns. */
4454 assign_parms (subr
);
4456 /* If function gets a static chain arg, store it. */
4457 if (cfun
->static_chain_decl
)
4459 tree parm
= cfun
->static_chain_decl
;
4460 rtx local
, chain
, insn
;
4462 local
= gen_reg_rtx (Pmode
);
4463 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
4465 set_decl_incoming_rtl (parm
, chain
, false);
4466 SET_DECL_RTL (parm
, local
);
4467 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4469 insn
= emit_move_insn (local
, chain
);
4471 /* Mark the register as eliminable, similar to parameters. */
4473 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
4474 set_unique_reg_note (insn
, REG_EQUIV
, chain
);
4477 /* If the function receives a non-local goto, then store the
4478 bits we need to restore the frame pointer. */
4479 if (cfun
->nonlocal_goto_save_area
)
4484 /* ??? We need to do this save early. Unfortunately here is
4485 before the frame variable gets declared. Help out... */
4486 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4487 if (!DECL_RTL_SET_P (var
))
4490 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4491 cfun
->nonlocal_goto_save_area
,
4492 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4493 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4494 r_save
= convert_memory_address (Pmode
, r_save
);
4496 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4497 update_nonlocal_goto_save_area ();
4500 /* The following was moved from init_function_start.
4501 The move is supposed to make sdb output more accurate. */
4502 /* Indicate the beginning of the function body,
4503 as opposed to parm setup. */
4504 emit_note (NOTE_INSN_FUNCTION_BEG
);
4506 gcc_assert (NOTE_P (get_last_insn ()));
4508 parm_birth_insn
= get_last_insn ();
4513 PROFILE_HOOK (current_function_funcdef_no
);
4517 /* After the display initializations is where the stack checking
4519 if(flag_stack_check
)
4520 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4522 /* Make sure there is a line number after the function entry setup code. */
4523 force_next_line_note ();
4526 /* Undo the effects of init_dummy_function_start. */
4528 expand_dummy_function_end (void)
4530 gcc_assert (in_dummy_function
);
4532 /* End any sequences that failed to be closed due to syntax errors. */
4533 while (in_sequence_p ())
4536 /* Outside function body, can't compute type's actual size
4537 until next function's body starts. */
4539 free_after_parsing (cfun
);
4540 free_after_compilation (cfun
);
4542 in_dummy_function
= false;
4545 /* Call DOIT for each hard register used as a return value from
4546 the current function. */
4549 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4551 rtx outgoing
= crtl
->return_rtx
;
4556 if (REG_P (outgoing
))
4557 (*doit
) (outgoing
, arg
);
4558 else if (GET_CODE (outgoing
) == PARALLEL
)
4562 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4564 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4566 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4573 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4579 clobber_return_register (void)
4581 diddle_return_value (do_clobber_return_reg
, NULL
);
4583 /* In case we do use pseudo to return value, clobber it too. */
4584 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4586 tree decl_result
= DECL_RESULT (current_function_decl
);
4587 rtx decl_rtl
= DECL_RTL (decl_result
);
4588 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4590 do_clobber_return_reg (decl_rtl
, NULL
);
4596 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4602 use_return_register (void)
4604 diddle_return_value (do_use_return_reg
, NULL
);
4607 /* Possibly warn about unused parameters. */
4609 do_warn_unused_parameter (tree fn
)
4613 for (decl
= DECL_ARGUMENTS (fn
);
4614 decl
; decl
= TREE_CHAIN (decl
))
4615 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4616 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4617 && !TREE_NO_WARNING (decl
))
4618 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4621 static GTY(()) rtx initial_trampoline
;
4623 /* Generate RTL for the end of the current function. */
4626 expand_function_end (void)
4630 /* If arg_pointer_save_area was referenced only from a nested
4631 function, we will not have initialized it yet. Do that now. */
4632 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4633 get_arg_pointer_save_area ();
4635 /* If we are doing generic stack checking and this function makes calls,
4636 do a stack probe at the start of the function to ensure we have enough
4637 space for another stack frame. */
4638 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4642 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4646 probe_stack_range (STACK_OLD_CHECK_PROTECT
,
4647 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4650 emit_insn_before (seq
, stack_check_probe_note
);
4655 /* End any sequences that failed to be closed due to syntax errors. */
4656 while (in_sequence_p ())
4659 clear_pending_stack_adjust ();
4660 do_pending_stack_adjust ();
4662 /* Output a linenumber for the end of the function.
4663 SDB depends on this. */
4664 force_next_line_note ();
4665 set_curr_insn_source_location (input_location
);
4667 /* Before the return label (if any), clobber the return
4668 registers so that they are not propagated live to the rest of
4669 the function. This can only happen with functions that drop
4670 through; if there had been a return statement, there would
4671 have either been a return rtx, or a jump to the return label.
4673 We delay actual code generation after the current_function_value_rtx
4675 clobber_after
= get_last_insn ();
4677 /* Output the label for the actual return from the function. */
4678 emit_label (return_label
);
4680 if (USING_SJLJ_EXCEPTIONS
)
4682 /* Let except.c know where it should emit the call to unregister
4683 the function context for sjlj exceptions. */
4684 if (flag_exceptions
)
4685 sjlj_emit_function_exit_after (get_last_insn ());
4689 /* We want to ensure that instructions that may trap are not
4690 moved into the epilogue by scheduling, because we don't
4691 always emit unwind information for the epilogue. */
4692 if (flag_non_call_exceptions
)
4693 emit_insn (gen_blockage ());
4696 /* If this is an implementation of throw, do what's necessary to
4697 communicate between __builtin_eh_return and the epilogue. */
4698 expand_eh_return ();
4700 /* If scalar return value was computed in a pseudo-reg, or was a named
4701 return value that got dumped to the stack, copy that to the hard
4703 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4705 tree decl_result
= DECL_RESULT (current_function_decl
);
4706 rtx decl_rtl
= DECL_RTL (decl_result
);
4708 if (REG_P (decl_rtl
)
4709 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4710 : DECL_REGISTER (decl_result
))
4712 rtx real_decl_rtl
= crtl
->return_rtx
;
4714 /* This should be set in assign_parms. */
4715 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4717 /* If this is a BLKmode structure being returned in registers,
4718 then use the mode computed in expand_return. Note that if
4719 decl_rtl is memory, then its mode may have been changed,
4720 but that crtl->return_rtx has not. */
4721 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4722 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4724 /* If a non-BLKmode return value should be padded at the least
4725 significant end of the register, shift it left by the appropriate
4726 amount. BLKmode results are handled using the group load/store
4728 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4729 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4731 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4732 REGNO (real_decl_rtl
)),
4734 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4736 /* If a named return value dumped decl_return to memory, then
4737 we may need to re-do the PROMOTE_MODE signed/unsigned
4739 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4741 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4742 promote_function_mode (TREE_TYPE (decl_result
),
4743 GET_MODE (decl_rtl
), &unsignedp
,
4744 TREE_TYPE (current_function_decl
), 1);
4746 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4748 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4750 /* If expand_function_start has created a PARALLEL for decl_rtl,
4751 move the result to the real return registers. Otherwise, do
4752 a group load from decl_rtl for a named return. */
4753 if (GET_CODE (decl_rtl
) == PARALLEL
)
4754 emit_group_move (real_decl_rtl
, decl_rtl
);
4756 emit_group_load (real_decl_rtl
, decl_rtl
,
4757 TREE_TYPE (decl_result
),
4758 int_size_in_bytes (TREE_TYPE (decl_result
)));
4760 /* In the case of complex integer modes smaller than a word, we'll
4761 need to generate some non-trivial bitfield insertions. Do that
4762 on a pseudo and not the hard register. */
4763 else if (GET_CODE (decl_rtl
) == CONCAT
4764 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4765 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4767 int old_generating_concat_p
;
4770 old_generating_concat_p
= generating_concat_p
;
4771 generating_concat_p
= 0;
4772 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4773 generating_concat_p
= old_generating_concat_p
;
4775 emit_move_insn (tmp
, decl_rtl
);
4776 emit_move_insn (real_decl_rtl
, tmp
);
4779 emit_move_insn (real_decl_rtl
, decl_rtl
);
4783 /* If returning a structure, arrange to return the address of the value
4784 in a place where debuggers expect to find it.
4786 If returning a structure PCC style,
4787 the caller also depends on this value.
4788 And cfun->returns_pcc_struct is not necessarily set. */
4789 if (cfun
->returns_struct
4790 || cfun
->returns_pcc_struct
)
4792 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4793 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4796 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4797 type
= TREE_TYPE (type
);
4799 value_address
= XEXP (value_address
, 0);
4801 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4802 current_function_decl
, true);
4804 /* Mark this as a function return value so integrate will delete the
4805 assignment and USE below when inlining this function. */
4806 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4808 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4809 value_address
= convert_memory_address (GET_MODE (outgoing
),
4812 emit_move_insn (outgoing
, value_address
);
4814 /* Show return register used to hold result (in this case the address
4816 crtl
->return_rtx
= outgoing
;
4819 /* Emit the actual code to clobber return register. */
4824 clobber_return_register ();
4828 emit_insn_after (seq
, clobber_after
);
4831 /* Output the label for the naked return from the function. */
4832 if (naked_return_label
)
4833 emit_label (naked_return_label
);
4835 /* @@@ This is a kludge. We want to ensure that instructions that
4836 may trap are not moved into the epilogue by scheduling, because
4837 we don't always emit unwind information for the epilogue. */
4838 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4839 emit_insn (gen_blockage ());
4841 /* If stack protection is enabled for this function, check the guard. */
4842 if (crtl
->stack_protect_guard
)
4843 stack_protect_epilogue ();
4845 /* If we had calls to alloca, and this machine needs
4846 an accurate stack pointer to exit the function,
4847 insert some code to save and restore the stack pointer. */
4848 if (! EXIT_IGNORE_STACK
4849 && cfun
->calls_alloca
)
4853 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4854 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4857 /* ??? This should no longer be necessary since stupid is no longer with
4858 us, but there are some parts of the compiler (eg reload_combine, and
4859 sh mach_dep_reorg) that still try and compute their own lifetime info
4860 instead of using the general framework. */
4861 use_return_register ();
4865 get_arg_pointer_save_area (void)
4867 rtx ret
= arg_pointer_save_area
;
4871 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4872 arg_pointer_save_area
= ret
;
4875 if (! crtl
->arg_pointer_save_area_init
)
4879 /* Save the arg pointer at the beginning of the function. The
4880 generated stack slot may not be a valid memory address, so we
4881 have to check it and fix it if necessary. */
4883 emit_move_insn (validize_mem (ret
),
4884 crtl
->args
.internal_arg_pointer
);
4888 push_topmost_sequence ();
4889 emit_insn_after (seq
, entry_of_function ());
4890 pop_topmost_sequence ();
4896 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4897 for the first time. */
4900 record_insns (rtx insns
, rtx end
, htab_t
*hashp
)
4903 htab_t hash
= *hashp
;
4907 = htab_create_ggc (17, htab_hash_pointer
, htab_eq_pointer
, NULL
);
4909 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
4911 void **slot
= htab_find_slot (hash
, tmp
, INSERT
);
4912 gcc_assert (*slot
== NULL
);
4917 /* INSN has been duplicated as COPY, as part of duping a basic block.
4918 If INSN is an epilogue insn, then record COPY as epilogue as well. */
4921 maybe_copy_epilogue_insn (rtx insn
, rtx copy
)
4925 if (epilogue_insn_hash
== NULL
4926 || htab_find (epilogue_insn_hash
, insn
) == NULL
)
4929 slot
= htab_find_slot (epilogue_insn_hash
, copy
, INSERT
);
4930 gcc_assert (*slot
== NULL
);
4934 /* Set the locator of the insn chain starting at INSN to LOC. */
4936 set_insn_locators (rtx insn
, int loc
)
4938 while (insn
!= NULL_RTX
)
4941 INSN_LOCATOR (insn
) = loc
;
4942 insn
= NEXT_INSN (insn
);
4946 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
4947 we can be running after reorg, SEQUENCE rtl is possible. */
4950 contains (const_rtx insn
, htab_t hash
)
4955 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4958 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4959 if (htab_find (hash
, XVECEXP (PATTERN (insn
), 0, i
)))
4964 return htab_find (hash
, insn
) != NULL
;
4968 prologue_epilogue_contains (const_rtx insn
)
4970 if (contains (insn
, prologue_insn_hash
))
4972 if (contains (insn
, epilogue_insn_hash
))
4978 /* Insert gen_return at the end of block BB. This also means updating
4979 block_for_insn appropriately. */
4982 emit_return_into_block (basic_block bb
)
4984 emit_jump_insn_after (gen_return (), BB_END (bb
));
4986 #endif /* HAVE_return */
4988 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4989 this into place with notes indicating where the prologue ends and where
4990 the epilogue begins. Update the basic block information when possible. */
4993 thread_prologue_and_epilogue_insns (void)
4997 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5000 #if defined (HAVE_epilogue) || defined(HAVE_return)
5001 rtx epilogue_end
= NULL_RTX
;
5005 rtl_profile_for_bb (ENTRY_BLOCK_PTR
);
5006 #ifdef HAVE_prologue
5010 seq
= gen_prologue ();
5013 /* Insert an explicit USE for the frame pointer
5014 if the profiling is on and the frame pointer is required. */
5015 if (crtl
->profile
&& frame_pointer_needed
)
5016 emit_use (hard_frame_pointer_rtx
);
5018 /* Retain a map of the prologue insns. */
5019 record_insns (seq
, NULL
, &prologue_insn_hash
);
5020 emit_note (NOTE_INSN_PROLOGUE_END
);
5022 #ifndef PROFILE_BEFORE_PROLOGUE
5023 /* Ensure that instructions are not moved into the prologue when
5024 profiling is on. The call to the profiling routine can be
5025 emitted within the live range of a call-clobbered register. */
5027 emit_insn (gen_blockage ());
5032 set_insn_locators (seq
, prologue_locator
);
5034 /* Can't deal with multiple successors of the entry block
5035 at the moment. Function should always have at least one
5037 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5039 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
5044 /* If the exit block has no non-fake predecessors, we don't need
5046 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5047 if ((e
->flags
& EDGE_FAKE
) == 0)
5052 rtl_profile_for_bb (EXIT_BLOCK_PTR
);
5054 if (optimize
&& HAVE_return
)
5056 /* If we're allowed to generate a simple return instruction,
5057 then by definition we don't need a full epilogue. Examine
5058 the block that falls through to EXIT. If it does not
5059 contain any code, examine its predecessors and try to
5060 emit (conditional) return instructions. */
5065 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5066 if (e
->flags
& EDGE_FALLTHRU
)
5072 /* Verify that there are no active instructions in the last block. */
5073 label
= BB_END (last
);
5074 while (label
&& !LABEL_P (label
))
5076 if (active_insn_p (label
))
5078 label
= PREV_INSN (label
);
5081 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5085 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5087 basic_block bb
= e
->src
;
5090 if (bb
== ENTRY_BLOCK_PTR
)
5097 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5103 /* If we have an unconditional jump, we can replace that
5104 with a simple return instruction. */
5105 if (simplejump_p (jump
))
5107 emit_return_into_block (bb
);
5111 /* If we have a conditional jump, we can try to replace
5112 that with a conditional return instruction. */
5113 else if (condjump_p (jump
))
5115 if (! redirect_jump (jump
, 0, 0))
5121 /* If this block has only one successor, it both jumps
5122 and falls through to the fallthru block, so we can't
5124 if (single_succ_p (bb
))
5136 /* Fix up the CFG for the successful change we just made. */
5137 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5140 /* Emit a return insn for the exit fallthru block. Whether
5141 this is still reachable will be determined later. */
5143 emit_barrier_after (BB_END (last
));
5144 emit_return_into_block (last
);
5145 epilogue_end
= BB_END (last
);
5146 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5152 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5153 this marker for the splits of EH_RETURN patterns, and nothing else
5154 uses the flag in the meantime. */
5155 epilogue_completed
= 1;
5157 #ifdef HAVE_eh_return
5158 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5159 some targets, these get split to a special version of the epilogue
5160 code. In order to be able to properly annotate these with unwind
5161 info, try to split them now. If we get a valid split, drop an
5162 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5163 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5165 rtx prev
, last
, trial
;
5167 if (e
->flags
& EDGE_FALLTHRU
)
5169 last
= BB_END (e
->src
);
5170 if (!eh_returnjump_p (last
))
5173 prev
= PREV_INSN (last
);
5174 trial
= try_split (PATTERN (last
), last
, 1);
5178 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
5179 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
5183 /* Find the edge that falls through to EXIT. Other edges may exist
5184 due to RETURN instructions, but those don't need epilogues.
5185 There really shouldn't be a mixture -- either all should have
5186 been converted or none, however... */
5188 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5189 if (e
->flags
& EDGE_FALLTHRU
)
5194 #ifdef HAVE_epilogue
5198 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5199 seq
= gen_epilogue ();
5200 emit_jump_insn (seq
);
5202 /* Retain a map of the epilogue insns. */
5203 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5204 set_insn_locators (seq
, epilogue_locator
);
5209 insert_insn_on_edge (seq
, e
);
5217 if (! next_active_insn (BB_END (e
->src
)))
5219 /* We have a fall-through edge to the exit block, the source is not
5220 at the end of the function, and there will be an assembler epilogue
5221 at the end of the function.
5222 We can't use force_nonfallthru here, because that would try to
5223 use return. Inserting a jump 'by hand' is extremely messy, so
5224 we take advantage of cfg_layout_finalize using
5225 fixup_fallthru_exit_predecessor. */
5226 cfg_layout_initialize (0);
5227 FOR_EACH_BB (cur_bb
)
5228 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5229 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5230 cur_bb
->aux
= cur_bb
->next_bb
;
5231 cfg_layout_finalize ();
5234 default_rtl_profile ();
5238 commit_edge_insertions ();
5240 /* The epilogue insns we inserted may cause the exit edge to no longer
5242 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5244 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5245 && returnjump_p (BB_END (e
->src
)))
5246 e
->flags
&= ~EDGE_FALLTHRU
;
5250 #ifdef HAVE_sibcall_epilogue
5251 /* Emit sibling epilogues before any sibling call sites. */
5252 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5254 basic_block bb
= e
->src
;
5255 rtx insn
= BB_END (bb
);
5258 || ! SIBLING_CALL_P (insn
))
5265 emit_note (NOTE_INSN_EPILOGUE_BEG
);
5266 emit_insn (gen_sibcall_epilogue ());
5270 /* Retain a map of the epilogue insns. Used in life analysis to
5271 avoid getting rid of sibcall epilogue insns. Do this before we
5272 actually emit the sequence. */
5273 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5274 set_insn_locators (seq
, epilogue_locator
);
5276 emit_insn_before (seq
, insn
);
5281 #ifdef HAVE_epilogue
5286 /* Similarly, move any line notes that appear after the epilogue.
5287 There is no need, however, to be quite so anal about the existence
5288 of such a note. Also possibly move
5289 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5291 for (insn
= epilogue_end
; insn
; insn
= next
)
5293 next
= NEXT_INSN (insn
);
5295 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5296 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5301 /* Threading the prologue and epilogue changes the artificial refs
5302 in the entry and exit blocks. */
5303 epilogue_completed
= 1;
5304 df_update_entry_exit_and_calls ();
5307 /* Reposition the prologue-end and epilogue-begin notes after
5308 instruction scheduling. */
5311 reposition_prologue_and_epilogue_notes (void)
5313 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5314 || defined (HAVE_sibcall_epilogue)
5315 /* Since the hash table is created on demand, the fact that it is
5316 non-null is a signal that it is non-empty. */
5317 if (prologue_insn_hash
!= NULL
)
5319 size_t len
= htab_elements (prologue_insn_hash
);
5320 rtx insn
, last
= NULL
, note
= NULL
;
5322 /* Scan from the beginning until we reach the last prologue insn. */
5323 /* ??? While we do have the CFG intact, there are two problems:
5324 (1) The prologue can contain loops (typically probing the stack),
5325 which means that the end of the prologue isn't in the first bb.
5326 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5327 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5331 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5334 else if (contains (insn
, prologue_insn_hash
))
5346 /* Scan forward looking for the PROLOGUE_END note. It should
5347 be right at the beginning of the block, possibly with other
5348 insn notes that got moved there. */
5349 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
5352 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5357 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5359 last
= NEXT_INSN (last
);
5360 reorder_insns (note
, note
, last
);
5364 if (epilogue_insn_hash
!= NULL
)
5369 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5371 rtx insn
, first
= NULL
, note
= NULL
;
5372 basic_block bb
= e
->src
;
5374 /* Scan from the beginning until we reach the first epilogue insn. */
5375 FOR_BB_INSNS (bb
, insn
)
5379 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5386 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
5396 /* If the function has a single basic block, and no real
5397 epilogue insns (e.g. sibcall with no cleanup), the
5398 epilogue note can get scheduled before the prologue
5399 note. If we have frame related prologue insns, having
5400 them scanned during the epilogue will result in a crash.
5401 In this case re-order the epilogue note to just before
5402 the last insn in the block. */
5404 first
= BB_END (bb
);
5406 if (PREV_INSN (first
) != note
)
5407 reorder_insns (note
, note
, PREV_INSN (first
));
5411 #endif /* HAVE_prologue or HAVE_epilogue */
5414 /* Returns the name of the current function. */
5416 current_function_name (void)
5418 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5423 rest_of_handle_check_leaf_regs (void)
5425 #ifdef LEAF_REGISTERS
5426 current_function_uses_only_leaf_regs
5427 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5432 /* Insert a TYPE into the used types hash table of CFUN. */
5435 used_types_insert_helper (tree type
, struct function
*func
)
5437 if (type
!= NULL
&& func
!= NULL
)
5441 if (func
->used_types_hash
== NULL
)
5442 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5443 htab_eq_pointer
, NULL
);
5444 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5450 /* Given a type, insert it into the used hash table in cfun. */
5452 used_types_insert (tree t
)
5454 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5456 t
= TYPE_MAIN_VARIANT (t
);
5457 if (debug_info_level
> DINFO_LEVEL_NONE
)
5460 used_types_insert_helper (t
, cfun
);
5462 /* So this might be a type referenced by a global variable.
5463 Record that type so that we can later decide to emit its debug
5465 types_used_by_cur_var_decl
=
5466 tree_cons (t
, NULL
, types_used_by_cur_var_decl
);
5471 /* Helper to Hash a struct types_used_by_vars_entry. */
5474 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
5476 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
5478 return iterative_hash_object (entry
->type
,
5479 iterative_hash_object (entry
->var_decl
, 0));
5482 /* Hash function of the types_used_by_vars_entry hash table. */
5485 types_used_by_vars_do_hash (const void *x
)
5487 const struct types_used_by_vars_entry
*entry
=
5488 (const struct types_used_by_vars_entry
*) x
;
5490 return hash_types_used_by_vars_entry (entry
);
5493 /*Equality function of the types_used_by_vars_entry hash table. */
5496 types_used_by_vars_eq (const void *x1
, const void *x2
)
5498 const struct types_used_by_vars_entry
*e1
=
5499 (const struct types_used_by_vars_entry
*) x1
;
5500 const struct types_used_by_vars_entry
*e2
=
5501 (const struct types_used_by_vars_entry
*)x2
;
5503 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
5506 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5509 types_used_by_var_decl_insert (tree type
, tree var_decl
)
5511 if (type
!= NULL
&& var_decl
!= NULL
)
5514 struct types_used_by_vars_entry e
;
5515 e
.var_decl
= var_decl
;
5517 if (types_used_by_vars_hash
== NULL
)
5518 types_used_by_vars_hash
=
5519 htab_create_ggc (37, types_used_by_vars_do_hash
,
5520 types_used_by_vars_eq
, NULL
);
5521 slot
= htab_find_slot_with_hash (types_used_by_vars_hash
, &e
,
5522 hash_types_used_by_vars_entry (&e
), INSERT
);
5525 struct types_used_by_vars_entry
*entry
;
5526 entry
= (struct types_used_by_vars_entry
*) ggc_alloc
5527 (sizeof (struct types_used_by_vars_entry
));
5529 entry
->var_decl
= var_decl
;
5535 struct rtl_opt_pass pass_leaf_regs
=
5541 rest_of_handle_check_leaf_regs
, /* execute */
5544 0, /* static_pass_number */
5545 TV_NONE
, /* tv_id */
5546 0, /* properties_required */
5547 0, /* properties_provided */
5548 0, /* properties_destroyed */
5549 0, /* todo_flags_start */
5550 0 /* todo_flags_finish */
5555 rest_of_handle_thread_prologue_and_epilogue (void)
5558 cleanup_cfg (CLEANUP_EXPENSIVE
);
5559 /* On some machines, the prologue and epilogue code, or parts thereof,
5560 can be represented as RTL. Doing so lets us schedule insns between
5561 it and the rest of the code and also allows delayed branch
5562 scheduling to operate in the epilogue. */
5564 thread_prologue_and_epilogue_insns ();
5568 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5572 "pro_and_epilogue", /* name */
5574 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5577 0, /* static_pass_number */
5578 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5579 0, /* properties_required */
5580 0, /* properties_provided */
5581 0, /* properties_destroyed */
5582 TODO_verify_flow
, /* todo_flags_start */
5585 TODO_df_finish
| TODO_verify_rtl_sharing
|
5586 TODO_ggc_collect
/* todo_flags_finish */
5591 /* This mini-pass fixes fall-out from SSA in asm statements that have
5592 in-out constraints. Say you start with
5595 asm ("": "+mr" (inout));
5598 which is transformed very early to use explicit output and match operands:
5601 asm ("": "=mr" (inout) : "0" (inout));
5604 Or, after SSA and copyprop,
5606 asm ("": "=mr" (inout_2) : "0" (inout_1));
5609 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5610 they represent two separate values, so they will get different pseudo
5611 registers during expansion. Then, since the two operands need to match
5612 per the constraints, but use different pseudo registers, reload can
5613 only register a reload for these operands. But reloads can only be
5614 satisfied by hardregs, not by memory, so we need a register for this
5615 reload, just because we are presented with non-matching operands.
5616 So, even though we allow memory for this operand, no memory can be
5617 used for it, just because the two operands don't match. This can
5618 cause reload failures on register-starved targets.
5620 So it's a symptom of reload not being able to use memory for reloads
5621 or, alternatively it's also a symptom of both operands not coming into
5622 reload as matching (in which case the pseudo could go to memory just
5623 fine, as the alternative allows it, and no reload would be necessary).
5624 We fix the latter problem here, by transforming
5626 asm ("": "=mr" (inout_2) : "0" (inout_1));
5631 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5634 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5637 bool changed
= false;
5638 rtx op
= SET_SRC (p_sets
[0]);
5639 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5640 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5641 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
5643 memset (output_matched
, 0, noutputs
* sizeof (bool));
5644 for (i
= 0; i
< ninputs
; i
++)
5646 rtx input
, output
, insns
;
5647 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5651 if (*constraint
== '%')
5654 match
= strtoul (constraint
, &end
, 10);
5655 if (end
== constraint
)
5658 gcc_assert (match
< noutputs
);
5659 output
= SET_DEST (p_sets
[match
]);
5660 input
= RTVEC_ELT (inputs
, i
);
5661 /* Only do the transformation for pseudos. */
5662 if (! REG_P (output
)
5663 || rtx_equal_p (output
, input
)
5664 || (GET_MODE (input
) != VOIDmode
5665 && GET_MODE (input
) != GET_MODE (output
)))
5668 /* We can't do anything if the output is also used as input,
5669 as we're going to overwrite it. */
5670 for (j
= 0; j
< ninputs
; j
++)
5671 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5676 /* Avoid changing the same input several times. For
5677 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5678 only change in once (to out1), rather than changing it
5679 first to out1 and afterwards to out2. */
5682 for (j
= 0; j
< noutputs
; j
++)
5683 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5688 output_matched
[match
] = true;
5691 emit_move_insn (output
, input
);
5692 insns
= get_insns ();
5694 emit_insn_before (insns
, insn
);
5696 /* Now replace all mentions of the input with output. We can't
5697 just replace the occurrence in inputs[i], as the register might
5698 also be used in some other input (or even in an address of an
5699 output), which would mean possibly increasing the number of
5700 inputs by one (namely 'output' in addition), which might pose
5701 a too complicated problem for reload to solve. E.g. this situation:
5703 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5705 Here 'input' is used in two occurrences as input (once for the
5706 input operand, once for the address in the second output operand).
5707 If we would replace only the occurrence of the input operand (to
5708 make the matching) we would be left with this:
5711 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5713 Now we suddenly have two different input values (containing the same
5714 value, but different pseudos) where we formerly had only one.
5715 With more complicated asms this might lead to reload failures
5716 which wouldn't have happen without this pass. So, iterate over
5717 all operands and replace all occurrences of the register used. */
5718 for (j
= 0; j
< noutputs
; j
++)
5719 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5720 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5721 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5723 for (j
= 0; j
< ninputs
; j
++)
5724 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5725 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5732 df_insn_rescan (insn
);
5736 rest_of_match_asm_constraints (void)
5739 rtx insn
, pat
, *p_sets
;
5742 if (!crtl
->has_asm_statement
)
5745 df_set_flags (DF_DEFER_INSN_RESCAN
);
5748 FOR_BB_INSNS (bb
, insn
)
5753 pat
= PATTERN (insn
);
5754 if (GET_CODE (pat
) == PARALLEL
)
5755 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5756 else if (GET_CODE (pat
) == SET
)
5757 p_sets
= &PATTERN (insn
), noutputs
= 1;
5761 if (GET_CODE (*p_sets
) == SET
5762 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5763 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5767 return TODO_df_finish
;
5770 struct rtl_opt_pass pass_match_asm_constraints
=
5774 "asmcons", /* name */
5776 rest_of_match_asm_constraints
, /* execute */
5779 0, /* static_pass_number */
5780 TV_NONE
, /* tv_id */
5781 0, /* properties_required */
5782 0, /* properties_provided */
5783 0, /* properties_destroyed */
5784 0, /* todo_flags_start */
5785 TODO_dump_func
/* todo_flags_finish */
5790 #include "gt-function.h"