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 2010, 2011 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"
40 #include "rtl-error.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
57 #include "integrate.h"
58 #include "langhooks.h"
60 #include "cfglayout.h"
62 #include "tree-pass.h"
68 /* So we can assign to cfun in this file. */
71 #ifndef STACK_ALIGNMENT_NEEDED
72 #define STACK_ALIGNMENT_NEEDED 1
75 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
77 /* Some systems use __main in a way incompatible with its use in gcc, in these
78 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
79 give the same symbol without quotes for an alternative entry point. You
80 must define both, or neither. */
82 #define NAME__MAIN "__main"
85 /* Round a value to the lowest integer less than it that is a multiple of
86 the required alignment. Avoid using division in case the value is
87 negative. Assume the alignment is a power of two. */
88 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
90 /* Similar, but round to the next highest integer that meets the
92 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
94 /* Nonzero if function being compiled doesn't contain any calls
95 (ignoring the prologue and epilogue). This is set prior to
96 local register allocation and is valid for the remaining
98 int current_function_is_leaf
;
100 /* Nonzero if function being compiled doesn't modify the stack pointer
101 (ignoring the prologue and epilogue). This is only valid after
102 pass_stack_ptr_mod has run. */
103 int current_function_sp_is_unchanging
;
105 /* Nonzero if the function being compiled is a leaf function which only
106 uses leaf registers. This is valid after reload (specifically after
107 sched2) and is useful only if the port defines LEAF_REGISTERS. */
108 int current_function_uses_only_leaf_regs
;
110 /* Nonzero once virtual register instantiation has been done.
111 assign_stack_local uses frame_pointer_rtx when this is nonzero.
112 calls.c:emit_library_call_value_1 uses it to set up
113 post-instantiation libcalls. */
114 int virtuals_instantiated
;
116 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
117 static GTY(()) int funcdef_no
;
119 /* These variables hold pointers to functions to create and destroy
120 target specific, per-function data structures. */
121 struct machine_function
* (*init_machine_status
) (void);
123 /* The currently compiled function. */
124 struct function
*cfun
= 0;
126 /* These hashes record the prologue and epilogue insns. */
127 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
128 htab_t prologue_insn_hash
;
129 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
130 htab_t epilogue_insn_hash
;
133 htab_t types_used_by_vars_hash
= NULL
;
134 VEC(tree
,gc
) *types_used_by_cur_var_decl
;
136 /* Forward declarations. */
138 static struct temp_slot
*find_temp_slot_from_address (rtx
);
139 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
140 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
141 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
142 static int all_blocks (tree
, tree
*);
143 static tree
*get_block_vector (tree
, int *);
144 extern tree
debug_find_var_in_block_tree (tree
, tree
);
145 /* We always define `record_insns' even if it's not used so that we
146 can always export `prologue_epilogue_contains'. */
147 static void record_insns (rtx
, rtx
, htab_t
*) ATTRIBUTE_UNUSED
;
148 static bool contains (const_rtx
, htab_t
);
150 static void emit_return_into_block (basic_block
);
152 static void prepare_function_start (void);
153 static void do_clobber_return_reg (rtx
, void *);
154 static void do_use_return_reg (rtx
, void *);
155 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
157 /* Stack of nested functions. */
158 /* Keep track of the cfun stack. */
160 typedef struct function
*function_p
;
162 DEF_VEC_P(function_p
);
163 DEF_VEC_ALLOC_P(function_p
,heap
);
164 static VEC(function_p
,heap
) *function_context_stack
;
166 /* Save the current context for compilation of a nested function.
167 This is called from language-specific code. */
170 push_function_context (void)
173 allocate_struct_function (NULL
, false);
175 VEC_safe_push (function_p
, heap
, function_context_stack
, cfun
);
179 /* Restore the last saved context, at the end of a nested function.
180 This function is called from language-specific code. */
183 pop_function_context (void)
185 struct function
*p
= VEC_pop (function_p
, function_context_stack
);
187 current_function_decl
= p
->decl
;
189 /* Reset variables that have known state during rtx generation. */
190 virtuals_instantiated
= 0;
191 generating_concat_p
= 1;
194 /* Clear out all parts of the state in F that can safely be discarded
195 after the function has been parsed, but not compiled, to let
196 garbage collection reclaim the memory. */
199 free_after_parsing (struct function
*f
)
204 /* Clear out all parts of the state in F that can safely be discarded
205 after the function has been compiled, to let garbage collection
206 reclaim the memory. */
209 free_after_compilation (struct function
*f
)
211 prologue_insn_hash
= NULL
;
212 epilogue_insn_hash
= NULL
;
214 free (crtl
->emit
.regno_pointer_align
);
216 memset (crtl
, 0, sizeof (struct rtl_data
));
221 regno_reg_rtx
= NULL
;
222 insn_locators_free ();
225 /* Return size needed for stack frame based on slots so far allocated.
226 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
227 the caller may have to do that. */
230 get_frame_size (void)
232 if (FRAME_GROWS_DOWNWARD
)
233 return -frame_offset
;
238 /* Issue an error message and return TRUE if frame OFFSET overflows in
239 the signed target pointer arithmetics for function FUNC. Otherwise
243 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
245 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
247 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
248 /* Leave room for the fixed part of the frame. */
249 - 64 * UNITS_PER_WORD
)
251 error_at (DECL_SOURCE_LOCATION (func
),
252 "total size of local objects too large");
259 /* Return stack slot alignment in bits for TYPE and MODE. */
262 get_stack_local_alignment (tree type
, enum machine_mode mode
)
264 unsigned int alignment
;
267 alignment
= BIGGEST_ALIGNMENT
;
269 alignment
= GET_MODE_ALIGNMENT (mode
);
271 /* Allow the frond-end to (possibly) increase the alignment of this
274 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
276 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
279 /* Determine whether it is possible to fit a stack slot of size SIZE and
280 alignment ALIGNMENT into an area in the stack frame that starts at
281 frame offset START and has a length of LENGTH. If so, store the frame
282 offset to be used for the stack slot in *POFFSET and return true;
283 return false otherwise. This function will extend the frame size when
284 given a start/length pair that lies at the end of the frame. */
287 try_fit_stack_local (HOST_WIDE_INT start
, HOST_WIDE_INT length
,
288 HOST_WIDE_INT size
, unsigned int alignment
,
289 HOST_WIDE_INT
*poffset
)
291 HOST_WIDE_INT this_frame_offset
;
292 int frame_off
, frame_alignment
, frame_phase
;
294 /* Calculate how many bytes the start of local variables is off from
296 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
297 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
298 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
300 /* Round the frame offset to the specified alignment. */
302 /* We must be careful here, since FRAME_OFFSET might be negative and
303 division with a negative dividend isn't as well defined as we might
304 like. So we instead assume that ALIGNMENT is a power of two and
305 use logical operations which are unambiguous. */
306 if (FRAME_GROWS_DOWNWARD
)
308 = (FLOOR_ROUND (start
+ length
- size
- frame_phase
,
309 (unsigned HOST_WIDE_INT
) alignment
)
313 = (CEIL_ROUND (start
- frame_phase
,
314 (unsigned HOST_WIDE_INT
) alignment
)
317 /* See if it fits. If this space is at the edge of the frame,
318 consider extending the frame to make it fit. Our caller relies on
319 this when allocating a new slot. */
320 if (frame_offset
== start
&& this_frame_offset
< frame_offset
)
321 frame_offset
= this_frame_offset
;
322 else if (this_frame_offset
< start
)
324 else if (start
+ length
== frame_offset
325 && this_frame_offset
+ size
> start
+ length
)
326 frame_offset
= this_frame_offset
+ size
;
327 else if (this_frame_offset
+ size
> start
+ length
)
330 *poffset
= this_frame_offset
;
334 /* Create a new frame_space structure describing free space in the stack
335 frame beginning at START and ending at END, and chain it into the
336 function's frame_space_list. */
339 add_frame_space (HOST_WIDE_INT start
, HOST_WIDE_INT end
)
341 struct frame_space
*space
= ggc_alloc_frame_space ();
342 space
->next
= crtl
->frame_space_list
;
343 crtl
->frame_space_list
= space
;
344 space
->start
= start
;
345 space
->length
= end
- start
;
348 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
349 with machine mode MODE.
351 ALIGN controls the amount of alignment for the address of the slot:
352 0 means according to MODE,
353 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
354 -2 means use BITS_PER_UNIT,
355 positive specifies alignment boundary in bits.
357 KIND has ASLK_REDUCE_ALIGN bit set if it is OK to reduce
358 alignment and ASLK_RECORD_PAD bit set if we should remember
359 extra space we allocated for alignment purposes. When we are
360 called from assign_stack_temp_for_type, it is not set so we don't
361 track the same stack slot in two independent lists.
363 We do not round to stack_boundary here. */
366 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
370 int bigend_correction
= 0;
371 HOST_WIDE_INT slot_offset
= 0, old_frame_offset
;
372 unsigned int alignment
, alignment_in_bits
;
376 alignment
= get_stack_local_alignment (NULL
, mode
);
377 alignment
/= BITS_PER_UNIT
;
379 else if (align
== -1)
381 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
382 size
= CEIL_ROUND (size
, alignment
);
384 else if (align
== -2)
385 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
387 alignment
= align
/ BITS_PER_UNIT
;
389 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
391 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
392 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
394 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
395 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
398 if (SUPPORTS_STACK_ALIGNMENT
)
400 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
402 if (!crtl
->stack_realign_processed
)
403 crtl
->stack_alignment_estimated
= alignment_in_bits
;
406 /* If stack is realigned and stack alignment value
407 hasn't been finalized, it is OK not to increase
408 stack_alignment_estimated. The bigger alignment
409 requirement is recorded in stack_alignment_needed
411 gcc_assert (!crtl
->stack_realign_finalized
);
412 if (!crtl
->stack_realign_needed
)
414 /* It is OK to reduce the alignment as long as the
415 requested size is 0 or the estimated stack
416 alignment >= mode alignment. */
417 gcc_assert ((kind
& ASLK_REDUCE_ALIGN
)
419 || (crtl
->stack_alignment_estimated
420 >= GET_MODE_ALIGNMENT (mode
)));
421 alignment_in_bits
= crtl
->stack_alignment_estimated
;
422 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
428 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
429 crtl
->stack_alignment_needed
= alignment_in_bits
;
430 if (crtl
->max_used_stack_slot_alignment
< alignment_in_bits
)
431 crtl
->max_used_stack_slot_alignment
= alignment_in_bits
;
433 if (mode
!= BLKmode
|| size
!= 0)
435 if (kind
& ASLK_RECORD_PAD
)
437 struct frame_space
**psp
;
439 for (psp
= &crtl
->frame_space_list
; *psp
; psp
= &(*psp
)->next
)
441 struct frame_space
*space
= *psp
;
442 if (!try_fit_stack_local (space
->start
, space
->length
, size
,
443 alignment
, &slot_offset
))
446 if (slot_offset
> space
->start
)
447 add_frame_space (space
->start
, slot_offset
);
448 if (slot_offset
+ size
< space
->start
+ space
->length
)
449 add_frame_space (slot_offset
+ size
,
450 space
->start
+ space
->length
);
455 else if (!STACK_ALIGNMENT_NEEDED
)
457 slot_offset
= frame_offset
;
461 old_frame_offset
= frame_offset
;
463 if (FRAME_GROWS_DOWNWARD
)
465 frame_offset
-= size
;
466 try_fit_stack_local (frame_offset
, size
, size
, alignment
, &slot_offset
);
468 if (kind
& ASLK_RECORD_PAD
)
470 if (slot_offset
> frame_offset
)
471 add_frame_space (frame_offset
, slot_offset
);
472 if (slot_offset
+ size
< old_frame_offset
)
473 add_frame_space (slot_offset
+ size
, old_frame_offset
);
478 frame_offset
+= size
;
479 try_fit_stack_local (old_frame_offset
, size
, size
, alignment
, &slot_offset
);
481 if (kind
& ASLK_RECORD_PAD
)
483 if (slot_offset
> old_frame_offset
)
484 add_frame_space (old_frame_offset
, slot_offset
);
485 if (slot_offset
+ size
< frame_offset
)
486 add_frame_space (slot_offset
+ size
, frame_offset
);
491 /* On a big-endian machine, if we are allocating more space than we will use,
492 use the least significant bytes of those that are allocated. */
493 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
494 bigend_correction
= size
- GET_MODE_SIZE (mode
);
496 /* If we have already instantiated virtual registers, return the actual
497 address relative to the frame pointer. */
498 if (virtuals_instantiated
)
499 addr
= plus_constant (frame_pointer_rtx
,
501 (slot_offset
+ bigend_correction
502 + STARTING_FRAME_OFFSET
, Pmode
));
504 addr
= plus_constant (virtual_stack_vars_rtx
,
506 (slot_offset
+ bigend_correction
,
509 x
= gen_rtx_MEM (mode
, addr
);
510 set_mem_align (x
, alignment_in_bits
);
511 MEM_NOTRAP_P (x
) = 1;
514 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
516 if (frame_offset_overflow (frame_offset
, current_function_decl
))
522 /* Wrap up assign_stack_local_1 with last parameter as false. */
525 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
527 return assign_stack_local_1 (mode
, size
, align
, ASLK_RECORD_PAD
);
531 /* In order to evaluate some expressions, such as function calls returning
532 structures in memory, we need to temporarily allocate stack locations.
533 We record each allocated temporary in the following structure.
535 Associated with each temporary slot is a nesting level. When we pop up
536 one level, all temporaries associated with the previous level are freed.
537 Normally, all temporaries are freed after the execution of the statement
538 in which they were created. However, if we are inside a ({...}) grouping,
539 the result may be in a temporary and hence must be preserved. If the
540 result could be in a temporary, we preserve it if we can determine which
541 one it is in. If we cannot determine which temporary may contain the
542 result, all temporaries are preserved. A temporary is preserved by
543 pretending it was allocated at the previous nesting level.
545 Automatic variables are also assigned temporary slots, at the nesting
546 level where they are defined. They are marked a "kept" so that
547 free_temp_slots will not free them. */
549 struct GTY(()) temp_slot
{
550 /* Points to next temporary slot. */
551 struct temp_slot
*next
;
552 /* Points to previous temporary slot. */
553 struct temp_slot
*prev
;
554 /* The rtx to used to reference the slot. */
556 /* The size, in units, of the slot. */
558 /* The type of the object in the slot, or zero if it doesn't correspond
559 to a type. We use this to determine whether a slot can be reused.
560 It can be reused if objects of the type of the new slot will always
561 conflict with objects of the type of the old slot. */
563 /* The alignment (in bits) of the slot. */
565 /* Nonzero if this temporary is currently in use. */
567 /* Nonzero if this temporary has its address taken. */
569 /* Nesting level at which this slot is being used. */
571 /* Nonzero if this should survive a call to free_temp_slots. */
573 /* The offset of the slot from the frame_pointer, including extra space
574 for alignment. This info is for combine_temp_slots. */
575 HOST_WIDE_INT base_offset
;
576 /* The size of the slot, including extra space for alignment. This
577 info is for combine_temp_slots. */
578 HOST_WIDE_INT full_size
;
581 /* A table of addresses that represent a stack slot. The table is a mapping
582 from address RTXen to a temp slot. */
583 static GTY((param_is(struct temp_slot_address_entry
))) htab_t temp_slot_address_table
;
585 /* Entry for the above hash table. */
586 struct GTY(()) temp_slot_address_entry
{
589 struct temp_slot
*temp_slot
;
592 /* Removes temporary slot TEMP from LIST. */
595 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
598 temp
->next
->prev
= temp
->prev
;
600 temp
->prev
->next
= temp
->next
;
604 temp
->prev
= temp
->next
= NULL
;
607 /* Inserts temporary slot TEMP to LIST. */
610 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
614 (*list
)->prev
= temp
;
619 /* Returns the list of used temp slots at LEVEL. */
621 static struct temp_slot
**
622 temp_slots_at_level (int level
)
624 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
625 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
627 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
630 /* Returns the maximal temporary slot level. */
633 max_slot_level (void)
635 if (!used_temp_slots
)
638 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
641 /* Moves temporary slot TEMP to LEVEL. */
644 move_slot_to_level (struct temp_slot
*temp
, int level
)
646 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
647 insert_slot_to_list (temp
, temp_slots_at_level (level
));
651 /* Make temporary slot TEMP available. */
654 make_slot_available (struct temp_slot
*temp
)
656 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
657 insert_slot_to_list (temp
, &avail_temp_slots
);
662 /* Compute the hash value for an address -> temp slot mapping.
663 The value is cached on the mapping entry. */
665 temp_slot_address_compute_hash (struct temp_slot_address_entry
*t
)
667 int do_not_record
= 0;
668 return hash_rtx (t
->address
, GET_MODE (t
->address
),
669 &do_not_record
, NULL
, false);
672 /* Return the hash value for an address -> temp slot mapping. */
674 temp_slot_address_hash (const void *p
)
676 const struct temp_slot_address_entry
*t
;
677 t
= (const struct temp_slot_address_entry
*) p
;
681 /* Compare two address -> temp slot mapping entries. */
683 temp_slot_address_eq (const void *p1
, const void *p2
)
685 const struct temp_slot_address_entry
*t1
, *t2
;
686 t1
= (const struct temp_slot_address_entry
*) p1
;
687 t2
= (const struct temp_slot_address_entry
*) p2
;
688 return exp_equiv_p (t1
->address
, t2
->address
, 0, true);
691 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
693 insert_temp_slot_address (rtx address
, struct temp_slot
*temp_slot
)
696 struct temp_slot_address_entry
*t
= ggc_alloc_temp_slot_address_entry ();
697 t
->address
= address
;
698 t
->temp_slot
= temp_slot
;
699 t
->hash
= temp_slot_address_compute_hash (t
);
700 slot
= htab_find_slot_with_hash (temp_slot_address_table
, t
, t
->hash
, INSERT
);
704 /* Remove an address -> temp slot mapping entry if the temp slot is
705 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
707 remove_unused_temp_slot_addresses_1 (void **slot
, void *data ATTRIBUTE_UNUSED
)
709 const struct temp_slot_address_entry
*t
;
710 t
= (const struct temp_slot_address_entry
*) *slot
;
711 if (! t
->temp_slot
->in_use
)
716 /* Remove all mappings of addresses to unused temp slots. */
718 remove_unused_temp_slot_addresses (void)
720 htab_traverse (temp_slot_address_table
,
721 remove_unused_temp_slot_addresses_1
,
725 /* Find the temp slot corresponding to the object at address X. */
727 static struct temp_slot
*
728 find_temp_slot_from_address (rtx x
)
731 struct temp_slot_address_entry tmp
, *t
;
733 /* First try the easy way:
734 See if X exists in the address -> temp slot mapping. */
736 tmp
.temp_slot
= NULL
;
737 tmp
.hash
= temp_slot_address_compute_hash (&tmp
);
738 t
= (struct temp_slot_address_entry
*)
739 htab_find_with_hash (temp_slot_address_table
, &tmp
, tmp
.hash
);
743 /* If we have a sum involving a register, see if it points to a temp
745 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
746 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
748 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
749 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
752 /* Last resort: Address is a virtual stack var address. */
753 if (GET_CODE (x
) == PLUS
754 && XEXP (x
, 0) == virtual_stack_vars_rtx
755 && CONST_INT_P (XEXP (x
, 1)))
758 for (i
= max_slot_level (); i
>= 0; i
--)
759 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
761 if (INTVAL (XEXP (x
, 1)) >= p
->base_offset
762 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
)
770 /* Allocate a temporary stack slot and record it for possible later
773 MODE is the machine mode to be given to the returned rtx.
775 SIZE is the size in units of the space required. We do no rounding here
776 since assign_stack_local will do any required rounding.
778 KEEP is 1 if this slot is to be retained after a call to
779 free_temp_slots. Automatic variables for a block are allocated
780 with this flag. KEEP values of 2 or 3 were needed respectively
781 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
782 or for SAVE_EXPRs, but they are now unused.
784 TYPE is the type that will be used for the stack slot. */
787 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
791 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
794 /* If SIZE is -1 it means that somebody tried to allocate a temporary
795 of a variable size. */
796 gcc_assert (size
!= -1);
798 /* These are now unused. */
799 gcc_assert (keep
<= 1);
801 align
= get_stack_local_alignment (type
, mode
);
803 /* Try to find an available, already-allocated temporary of the proper
804 mode which meets the size and alignment requirements. Choose the
805 smallest one with the closest alignment.
807 If assign_stack_temp is called outside of the tree->rtl expansion,
808 we cannot reuse the stack slots (that may still refer to
809 VIRTUAL_STACK_VARS_REGNUM). */
810 if (!virtuals_instantiated
)
812 for (p
= avail_temp_slots
; p
; p
= p
->next
)
814 if (p
->align
>= align
&& p
->size
>= size
815 && GET_MODE (p
->slot
) == mode
816 && objects_must_conflict_p (p
->type
, type
)
817 && (best_p
== 0 || best_p
->size
> p
->size
818 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
820 if (p
->align
== align
&& p
->size
== size
)
823 cut_slot_from_list (selected
, &avail_temp_slots
);
832 /* Make our best, if any, the one to use. */
836 cut_slot_from_list (selected
, &avail_temp_slots
);
838 /* If there are enough aligned bytes left over, make them into a new
839 temp_slot so that the extra bytes don't get wasted. Do this only
840 for BLKmode slots, so that we can be sure of the alignment. */
841 if (GET_MODE (best_p
->slot
) == BLKmode
)
843 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
844 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
846 if (best_p
->size
- rounded_size
>= alignment
)
848 p
= ggc_alloc_temp_slot ();
849 p
->in_use
= p
->addr_taken
= 0;
850 p
->size
= best_p
->size
- rounded_size
;
851 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
852 p
->full_size
= best_p
->full_size
- rounded_size
;
853 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
854 p
->align
= best_p
->align
;
855 p
->type
= best_p
->type
;
856 insert_slot_to_list (p
, &avail_temp_slots
);
858 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
861 best_p
->size
= rounded_size
;
862 best_p
->full_size
= rounded_size
;
867 /* If we still didn't find one, make a new temporary. */
870 HOST_WIDE_INT frame_offset_old
= frame_offset
;
872 p
= ggc_alloc_temp_slot ();
874 /* We are passing an explicit alignment request to assign_stack_local.
875 One side effect of that is assign_stack_local will not round SIZE
876 to ensure the frame offset remains suitably aligned.
878 So for requests which depended on the rounding of SIZE, we go ahead
879 and round it now. We also make sure ALIGNMENT is at least
880 BIGGEST_ALIGNMENT. */
881 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
882 p
->slot
= assign_stack_local_1 (mode
,
892 /* The following slot size computation is necessary because we don't
893 know the actual size of the temporary slot until assign_stack_local
894 has performed all the frame alignment and size rounding for the
895 requested temporary. Note that extra space added for alignment
896 can be either above or below this stack slot depending on which
897 way the frame grows. We include the extra space if and only if it
898 is above this slot. */
899 if (FRAME_GROWS_DOWNWARD
)
900 p
->size
= frame_offset_old
- frame_offset
;
904 /* Now define the fields used by combine_temp_slots. */
905 if (FRAME_GROWS_DOWNWARD
)
907 p
->base_offset
= frame_offset
;
908 p
->full_size
= frame_offset_old
- frame_offset
;
912 p
->base_offset
= frame_offset_old
;
913 p
->full_size
= frame_offset
- frame_offset_old
;
923 p
->level
= temp_slot_level
;
926 pp
= temp_slots_at_level (p
->level
);
927 insert_slot_to_list (p
, pp
);
928 insert_temp_slot_address (XEXP (p
->slot
, 0), p
);
930 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
931 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
932 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
934 /* If we know the alias set for the memory that will be used, use
935 it. If there's no TYPE, then we don't know anything about the
936 alias set for the memory. */
937 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
938 set_mem_align (slot
, align
);
940 /* If a type is specified, set the relevant flags. */
943 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
944 gcc_checking_assert (!MEM_SCALAR_P (slot
) && !MEM_IN_STRUCT_P (slot
));
945 if (AGGREGATE_TYPE_P (type
) || TREE_CODE (type
) == COMPLEX_TYPE
)
946 MEM_IN_STRUCT_P (slot
) = 1;
948 MEM_SCALAR_P (slot
) = 1;
950 MEM_NOTRAP_P (slot
) = 1;
955 /* Allocate a temporary stack slot and record it for possible later
956 reuse. First three arguments are same as in preceding function. */
959 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
961 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
964 /* Assign a temporary.
965 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
966 and so that should be used in error messages. In either case, we
967 allocate of the given type.
968 KEEP is as for assign_stack_temp.
969 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
970 it is 0 if a register is OK.
971 DONT_PROMOTE is 1 if we should not promote values in register
975 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
976 int dont_promote ATTRIBUTE_UNUSED
)
979 enum machine_mode mode
;
984 if (DECL_P (type_or_decl
))
985 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
987 decl
= NULL
, type
= type_or_decl
;
989 mode
= TYPE_MODE (type
);
991 unsignedp
= TYPE_UNSIGNED (type
);
994 if (mode
== BLKmode
|| memory_required
)
996 HOST_WIDE_INT size
= int_size_in_bytes (type
);
999 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
1000 problems with allocating the stack space. */
1004 /* Unfortunately, we don't yet know how to allocate variable-sized
1005 temporaries. However, sometimes we can find a fixed upper limit on
1006 the size, so try that instead. */
1007 else if (size
== -1)
1008 size
= max_int_size_in_bytes (type
);
1010 /* The size of the temporary may be too large to fit into an integer. */
1011 /* ??? Not sure this should happen except for user silliness, so limit
1012 this to things that aren't compiler-generated temporaries. The
1013 rest of the time we'll die in assign_stack_temp_for_type. */
1014 if (decl
&& size
== -1
1015 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
1017 error ("size of variable %q+D is too large", decl
);
1021 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
1027 mode
= promote_mode (type
, mode
, &unsignedp
);
1030 return gen_reg_rtx (mode
);
1033 /* Combine temporary stack slots which are adjacent on the stack.
1035 This allows for better use of already allocated stack space. This is only
1036 done for BLKmode slots because we can be sure that we won't have alignment
1037 problems in this case. */
1040 combine_temp_slots (void)
1042 struct temp_slot
*p
, *q
, *next
, *next_q
;
1045 /* We can't combine slots, because the information about which slot
1046 is in which alias set will be lost. */
1047 if (flag_strict_aliasing
)
1050 /* If there are a lot of temp slots, don't do anything unless
1051 high levels of optimization. */
1052 if (! flag_expensive_optimizations
)
1053 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
1054 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
1057 for (p
= avail_temp_slots
; p
; p
= next
)
1063 if (GET_MODE (p
->slot
) != BLKmode
)
1066 for (q
= p
->next
; q
; q
= next_q
)
1072 if (GET_MODE (q
->slot
) != BLKmode
)
1075 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
1077 /* Q comes after P; combine Q into P. */
1079 p
->full_size
+= q
->full_size
;
1082 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
1084 /* P comes after Q; combine P into Q. */
1086 q
->full_size
+= p
->full_size
;
1091 cut_slot_from_list (q
, &avail_temp_slots
);
1094 /* Either delete P or advance past it. */
1096 cut_slot_from_list (p
, &avail_temp_slots
);
1100 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1101 slot that previously was known by OLD_RTX. */
1104 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
1106 struct temp_slot
*p
;
1108 if (rtx_equal_p (old_rtx
, new_rtx
))
1111 p
= find_temp_slot_from_address (old_rtx
);
1113 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1114 NEW_RTX is a register, see if one operand of the PLUS is a
1115 temporary location. If so, NEW_RTX points into it. Otherwise,
1116 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1117 in common between them. If so, try a recursive call on those
1121 if (GET_CODE (old_rtx
) != PLUS
)
1124 if (REG_P (new_rtx
))
1126 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
1127 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
1130 else if (GET_CODE (new_rtx
) != PLUS
)
1133 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
1134 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
1135 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
1136 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
1137 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
1138 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
1139 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
1140 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
1145 /* Otherwise add an alias for the temp's address. */
1146 insert_temp_slot_address (new_rtx
, p
);
1149 /* If X could be a reference to a temporary slot, mark the fact that its
1150 address was taken. */
1153 mark_temp_addr_taken (rtx x
)
1155 struct temp_slot
*p
;
1160 /* If X is not in memory or is at a constant address, it cannot be in
1161 a temporary slot. */
1162 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1165 p
= find_temp_slot_from_address (XEXP (x
, 0));
1170 /* If X could be a reference to a temporary slot, mark that slot as
1171 belonging to the to one level higher than the current level. If X
1172 matched one of our slots, just mark that one. Otherwise, we can't
1173 easily predict which it is, so upgrade all of them. Kept slots
1174 need not be touched.
1176 This is called when an ({...}) construct occurs and a statement
1177 returns a value in memory. */
1180 preserve_temp_slots (rtx x
)
1182 struct temp_slot
*p
= 0, *next
;
1184 /* If there is no result, we still might have some objects whose address
1185 were taken, so we need to make sure they stay around. */
1188 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1193 move_slot_to_level (p
, temp_slot_level
- 1);
1199 /* If X is a register that is being used as a pointer, see if we have
1200 a temporary slot we know it points to. To be consistent with
1201 the code below, we really should preserve all non-kept slots
1202 if we can't find a match, but that seems to be much too costly. */
1203 if (REG_P (x
) && REG_POINTER (x
))
1204 p
= find_temp_slot_from_address (x
);
1206 /* If X is not in memory or is at a constant address, it cannot be in
1207 a temporary slot, but it can contain something whose address was
1209 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1211 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1216 move_slot_to_level (p
, temp_slot_level
- 1);
1222 /* First see if we can find a match. */
1224 p
= find_temp_slot_from_address (XEXP (x
, 0));
1228 /* Move everything at our level whose address was taken to our new
1229 level in case we used its address. */
1230 struct temp_slot
*q
;
1232 if (p
->level
== temp_slot_level
)
1234 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1238 if (p
!= q
&& q
->addr_taken
)
1239 move_slot_to_level (q
, temp_slot_level
- 1);
1242 move_slot_to_level (p
, temp_slot_level
- 1);
1248 /* Otherwise, preserve all non-kept slots at this level. */
1249 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1254 move_slot_to_level (p
, temp_slot_level
- 1);
1258 /* Free all temporaries used so far. This is normally called at the
1259 end of generating code for a statement. */
1262 free_temp_slots (void)
1264 struct temp_slot
*p
, *next
;
1265 bool some_available
= false;
1267 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1273 make_slot_available (p
);
1274 some_available
= true;
1280 remove_unused_temp_slot_addresses ();
1281 combine_temp_slots ();
1285 /* Push deeper into the nesting level for stack temporaries. */
1288 push_temp_slots (void)
1293 /* Pop a temporary nesting level. All slots in use in the current level
1297 pop_temp_slots (void)
1299 struct temp_slot
*p
, *next
;
1300 bool some_available
= false;
1302 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1305 make_slot_available (p
);
1306 some_available
= true;
1311 remove_unused_temp_slot_addresses ();
1312 combine_temp_slots ();
1318 /* Initialize temporary slots. */
1321 init_temp_slots (void)
1323 /* We have not allocated any temporaries yet. */
1324 avail_temp_slots
= 0;
1325 used_temp_slots
= 0;
1326 temp_slot_level
= 0;
1328 /* Set up the table to map addresses to temp slots. */
1329 if (! temp_slot_address_table
)
1330 temp_slot_address_table
= htab_create_ggc (32,
1331 temp_slot_address_hash
,
1332 temp_slot_address_eq
,
1335 htab_empty (temp_slot_address_table
);
1338 /* These routines are responsible for converting virtual register references
1339 to the actual hard register references once RTL generation is complete.
1341 The following four variables are used for communication between the
1342 routines. They contain the offsets of the virtual registers from their
1343 respective hard registers. */
1345 static int in_arg_offset
;
1346 static int var_offset
;
1347 static int dynamic_offset
;
1348 static int out_arg_offset
;
1349 static int cfa_offset
;
1351 /* In most machines, the stack pointer register is equivalent to the bottom
1354 #ifndef STACK_POINTER_OFFSET
1355 #define STACK_POINTER_OFFSET 0
1358 /* If not defined, pick an appropriate default for the offset of dynamically
1359 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1360 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1362 #ifndef STACK_DYNAMIC_OFFSET
1364 /* The bottom of the stack points to the actual arguments. If
1365 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1366 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1367 stack space for register parameters is not pushed by the caller, but
1368 rather part of the fixed stack areas and hence not included in
1369 `crtl->outgoing_args_size'. Nevertheless, we must allow
1370 for it when allocating stack dynamic objects. */
1372 #if defined(REG_PARM_STACK_SPACE)
1373 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1374 ((ACCUMULATE_OUTGOING_ARGS \
1375 ? (crtl->outgoing_args_size \
1376 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1377 : REG_PARM_STACK_SPACE (FNDECL))) \
1378 : 0) + (STACK_POINTER_OFFSET))
1380 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1381 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1382 + (STACK_POINTER_OFFSET))
1387 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1388 is a virtual register, return the equivalent hard register and set the
1389 offset indirectly through the pointer. Otherwise, return 0. */
1392 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1395 HOST_WIDE_INT offset
;
1397 if (x
== virtual_incoming_args_rtx
)
1399 if (stack_realign_drap
)
1401 /* Replace virtual_incoming_args_rtx with internal arg
1402 pointer if DRAP is used to realign stack. */
1403 new_rtx
= crtl
->args
.internal_arg_pointer
;
1407 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1409 else if (x
== virtual_stack_vars_rtx
)
1410 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1411 else if (x
== virtual_stack_dynamic_rtx
)
1412 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1413 else if (x
== virtual_outgoing_args_rtx
)
1414 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1415 else if (x
== virtual_cfa_rtx
)
1417 #ifdef FRAME_POINTER_CFA_OFFSET
1418 new_rtx
= frame_pointer_rtx
;
1420 new_rtx
= arg_pointer_rtx
;
1422 offset
= cfa_offset
;
1424 else if (x
== virtual_preferred_stack_boundary_rtx
)
1426 new_rtx
= GEN_INT (crtl
->preferred_stack_boundary
/ BITS_PER_UNIT
);
1436 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1437 Instantiate any virtual registers present inside of *LOC. The expression
1438 is simplified, as much as possible, but is not to be considered "valid"
1439 in any sense implied by the target. If any change is made, set CHANGED
1443 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1445 HOST_WIDE_INT offset
;
1446 bool *changed
= (bool *) data
;
1453 switch (GET_CODE (x
))
1456 new_rtx
= instantiate_new_reg (x
, &offset
);
1459 *loc
= plus_constant (new_rtx
, offset
);
1466 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1469 new_rtx
= plus_constant (new_rtx
, offset
);
1470 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1476 /* FIXME -- from old code */
1477 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1478 we can commute the PLUS and SUBREG because pointers into the
1479 frame are well-behaved. */
1489 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1490 matches the predicate for insn CODE operand OPERAND. */
1493 safe_insn_predicate (int code
, int operand
, rtx x
)
1495 return code
< 0 || insn_operand_matches ((enum insn_code
) code
, operand
, x
);
1498 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1499 registers present inside of insn. The result will be a valid insn. */
1502 instantiate_virtual_regs_in_insn (rtx insn
)
1504 HOST_WIDE_INT offset
;
1506 bool any_change
= false;
1507 rtx set
, new_rtx
, x
, seq
;
1509 /* There are some special cases to be handled first. */
1510 set
= single_set (insn
);
1513 /* We're allowed to assign to a virtual register. This is interpreted
1514 to mean that the underlying register gets assigned the inverse
1515 transformation. This is used, for example, in the handling of
1517 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1522 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1523 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1525 x
= force_operand (x
, new_rtx
);
1527 emit_move_insn (new_rtx
, x
);
1532 emit_insn_before (seq
, insn
);
1537 /* Handle a straight copy from a virtual register by generating a
1538 new add insn. The difference between this and falling through
1539 to the generic case is avoiding a new pseudo and eliminating a
1540 move insn in the initial rtl stream. */
1541 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1542 if (new_rtx
&& offset
!= 0
1543 && REG_P (SET_DEST (set
))
1544 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1548 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1549 new_rtx
, GEN_INT (offset
), SET_DEST (set
),
1550 1, OPTAB_LIB_WIDEN
);
1551 if (x
!= SET_DEST (set
))
1552 emit_move_insn (SET_DEST (set
), x
);
1557 emit_insn_before (seq
, insn
);
1562 extract_insn (insn
);
1563 insn_code
= INSN_CODE (insn
);
1565 /* Handle a plus involving a virtual register by determining if the
1566 operands remain valid if they're modified in place. */
1567 if (GET_CODE (SET_SRC (set
)) == PLUS
1568 && recog_data
.n_operands
>= 3
1569 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1570 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1571 && CONST_INT_P (recog_data
.operand
[2])
1572 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1574 offset
+= INTVAL (recog_data
.operand
[2]);
1576 /* If the sum is zero, then replace with a plain move. */
1578 && REG_P (SET_DEST (set
))
1579 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1582 emit_move_insn (SET_DEST (set
), new_rtx
);
1586 emit_insn_before (seq
, insn
);
1591 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1593 /* Using validate_change and apply_change_group here leaves
1594 recog_data in an invalid state. Since we know exactly what
1595 we want to check, do those two by hand. */
1596 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1597 && safe_insn_predicate (insn_code
, 2, x
))
1599 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1600 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1603 /* Fall through into the regular operand fixup loop in
1604 order to take care of operands other than 1 and 2. */
1610 extract_insn (insn
);
1611 insn_code
= INSN_CODE (insn
);
1614 /* In the general case, we expect virtual registers to appear only in
1615 operands, and then only as either bare registers or inside memories. */
1616 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1618 x
= recog_data
.operand
[i
];
1619 switch (GET_CODE (x
))
1623 rtx addr
= XEXP (x
, 0);
1624 bool changed
= false;
1626 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1631 x
= replace_equiv_address (x
, addr
);
1632 /* It may happen that the address with the virtual reg
1633 was valid (e.g. based on the virtual stack reg, which might
1634 be acceptable to the predicates with all offsets), whereas
1635 the address now isn't anymore, for instance when the address
1636 is still offsetted, but the base reg isn't virtual-stack-reg
1637 anymore. Below we would do a force_reg on the whole operand,
1638 but this insn might actually only accept memory. Hence,
1639 before doing that last resort, try to reload the address into
1640 a register, so this operand stays a MEM. */
1641 if (!safe_insn_predicate (insn_code
, i
, x
))
1643 addr
= force_reg (GET_MODE (addr
), addr
);
1644 x
= replace_equiv_address (x
, addr
);
1649 emit_insn_before (seq
, insn
);
1654 new_rtx
= instantiate_new_reg (x
, &offset
);
1655 if (new_rtx
== NULL
)
1663 /* Careful, special mode predicates may have stuff in
1664 insn_data[insn_code].operand[i].mode that isn't useful
1665 to us for computing a new value. */
1666 /* ??? Recognize address_operand and/or "p" constraints
1667 to see if (plus new offset) is a valid before we put
1668 this through expand_simple_binop. */
1669 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1670 GEN_INT (offset
), NULL_RTX
,
1671 1, OPTAB_LIB_WIDEN
);
1674 emit_insn_before (seq
, insn
);
1679 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1680 if (new_rtx
== NULL
)
1685 new_rtx
= expand_simple_binop (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1686 GEN_INT (offset
), NULL_RTX
,
1687 1, OPTAB_LIB_WIDEN
);
1690 emit_insn_before (seq
, insn
);
1692 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1693 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1701 /* At this point, X contains the new value for the operand.
1702 Validate the new value vs the insn predicate. Note that
1703 asm insns will have insn_code -1 here. */
1704 if (!safe_insn_predicate (insn_code
, i
, x
))
1709 gcc_assert (REGNO (x
) <= LAST_VIRTUAL_REGISTER
);
1710 x
= copy_to_reg (x
);
1713 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1717 emit_insn_before (seq
, insn
);
1720 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1726 /* Propagate operand changes into the duplicates. */
1727 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1728 *recog_data
.dup_loc
[i
]
1729 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1731 /* Force re-recognition of the instruction for validation. */
1732 INSN_CODE (insn
) = -1;
1735 if (asm_noperands (PATTERN (insn
)) >= 0)
1737 if (!check_asm_operands (PATTERN (insn
)))
1739 error_for_asm (insn
, "impossible constraint in %<asm%>");
1745 if (recog_memoized (insn
) < 0)
1746 fatal_insn_not_found (insn
);
1750 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1751 do any instantiation required. */
1754 instantiate_decl_rtl (rtx x
)
1761 /* If this is a CONCAT, recurse for the pieces. */
1762 if (GET_CODE (x
) == CONCAT
)
1764 instantiate_decl_rtl (XEXP (x
, 0));
1765 instantiate_decl_rtl (XEXP (x
, 1));
1769 /* If this is not a MEM, no need to do anything. Similarly if the
1770 address is a constant or a register that is not a virtual register. */
1775 if (CONSTANT_P (addr
)
1777 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1778 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1781 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1784 /* Helper for instantiate_decls called via walk_tree: Process all decls
1785 in the given DECL_VALUE_EXPR. */
1788 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1796 if (DECL_RTL_SET_P (t
))
1797 instantiate_decl_rtl (DECL_RTL (t
));
1798 if (TREE_CODE (t
) == PARM_DECL
&& DECL_NAMELESS (t
)
1799 && DECL_INCOMING_RTL (t
))
1800 instantiate_decl_rtl (DECL_INCOMING_RTL (t
));
1801 if ((TREE_CODE (t
) == VAR_DECL
1802 || TREE_CODE (t
) == RESULT_DECL
)
1803 && DECL_HAS_VALUE_EXPR_P (t
))
1805 tree v
= DECL_VALUE_EXPR (t
);
1806 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1813 /* Subroutine of instantiate_decls: Process all decls in the given
1814 BLOCK node and all its subblocks. */
1817 instantiate_decls_1 (tree let
)
1821 for (t
= BLOCK_VARS (let
); t
; t
= DECL_CHAIN (t
))
1823 if (DECL_RTL_SET_P (t
))
1824 instantiate_decl_rtl (DECL_RTL (t
));
1825 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1827 tree v
= DECL_VALUE_EXPR (t
);
1828 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1832 /* Process all subblocks. */
1833 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1834 instantiate_decls_1 (t
);
1837 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1838 all virtual registers in their DECL_RTL's. */
1841 instantiate_decls (tree fndecl
)
1846 /* Process all parameters of the function. */
1847 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= DECL_CHAIN (decl
))
1849 instantiate_decl_rtl (DECL_RTL (decl
));
1850 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1851 if (DECL_HAS_VALUE_EXPR_P (decl
))
1853 tree v
= DECL_VALUE_EXPR (decl
);
1854 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1858 if ((decl
= DECL_RESULT (fndecl
))
1859 && TREE_CODE (decl
) == RESULT_DECL
)
1861 if (DECL_RTL_SET_P (decl
))
1862 instantiate_decl_rtl (DECL_RTL (decl
));
1863 if (DECL_HAS_VALUE_EXPR_P (decl
))
1865 tree v
= DECL_VALUE_EXPR (decl
);
1866 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1870 /* Now process all variables defined in the function or its subblocks. */
1871 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1873 FOR_EACH_LOCAL_DECL (cfun
, ix
, decl
)
1874 if (DECL_RTL_SET_P (decl
))
1875 instantiate_decl_rtl (DECL_RTL (decl
));
1876 VEC_free (tree
, gc
, cfun
->local_decls
);
1879 /* Pass through the INSNS of function FNDECL and convert virtual register
1880 references to hard register references. */
1883 instantiate_virtual_regs (void)
1887 /* Compute the offsets to use for this function. */
1888 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1889 var_offset
= STARTING_FRAME_OFFSET
;
1890 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1891 out_arg_offset
= STACK_POINTER_OFFSET
;
1892 #ifdef FRAME_POINTER_CFA_OFFSET
1893 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1895 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1898 /* Initialize recognition, indicating that volatile is OK. */
1901 /* Scan through all the insns, instantiating every virtual register still
1903 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1906 /* These patterns in the instruction stream can never be recognized.
1907 Fortunately, they shouldn't contain virtual registers either. */
1908 if (GET_CODE (PATTERN (insn
)) == USE
1909 || GET_CODE (PATTERN (insn
)) == CLOBBER
1910 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1911 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1912 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1914 else if (DEBUG_INSN_P (insn
))
1915 for_each_rtx (&INSN_VAR_LOCATION (insn
),
1916 instantiate_virtual_regs_in_rtx
, NULL
);
1918 instantiate_virtual_regs_in_insn (insn
);
1920 if (INSN_DELETED_P (insn
))
1923 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1925 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1927 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1928 instantiate_virtual_regs_in_rtx
, NULL
);
1931 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1932 instantiate_decls (current_function_decl
);
1934 targetm
.instantiate_decls ();
1936 /* Indicate that, from now on, assign_stack_local should use
1937 frame_pointer_rtx. */
1938 virtuals_instantiated
= 1;
1940 /* See allocate_dynamic_stack_space for the rationale. */
1941 #ifdef SETJMP_VIA_SAVE_AREA
1942 if (flag_stack_usage
&& cfun
->calls_setjmp
)
1944 int align
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
1945 dynamic_offset
= (dynamic_offset
+ align
- 1) / align
* align
;
1946 current_function_dynamic_stack_size
1947 += current_function_dynamic_alloc_count
* dynamic_offset
;
1954 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1960 instantiate_virtual_regs
, /* execute */
1963 0, /* static_pass_number */
1964 TV_NONE
, /* tv_id */
1965 0, /* properties_required */
1966 0, /* properties_provided */
1967 0, /* properties_destroyed */
1968 0, /* todo_flags_start */
1969 TODO_dump_func
/* todo_flags_finish */
1974 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1975 This means a type for which function calls must pass an address to the
1976 function or get an address back from the function.
1977 EXP may be a type node or an expression (whose type is tested). */
1980 aggregate_value_p (const_tree exp
, const_tree fntype
)
1982 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1983 int i
, regno
, nregs
;
1987 switch (TREE_CODE (fntype
))
1991 tree fndecl
= get_callee_fndecl (fntype
);
1993 ? TREE_TYPE (fndecl
)
1994 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype
))));
1998 fntype
= TREE_TYPE (fntype
);
2003 case IDENTIFIER_NODE
:
2007 /* We don't expect other tree types here. */
2011 if (VOID_TYPE_P (type
))
2014 /* If a record should be passed the same as its first (and only) member
2015 don't pass it as an aggregate. */
2016 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2017 return aggregate_value_p (first_field (type
), fntype
);
2019 /* If the front end has decided that this needs to be passed by
2020 reference, do so. */
2021 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
2022 && DECL_BY_REFERENCE (exp
))
2025 /* Function types that are TREE_ADDRESSABLE force return in memory. */
2026 if (fntype
&& TREE_ADDRESSABLE (fntype
))
2029 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
2030 and thus can't be returned in registers. */
2031 if (TREE_ADDRESSABLE (type
))
2034 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
2037 /* Pointers-to-shared must be considered as aggregates for
2038 the purpose of passing them as return values, but only
2039 when the underlying mode of the representation would
2040 require that its value be passed on the stack.
2041 This occurs when using the 'struct' representation
2042 of a shared pointer. */
2043 if (flag_pcc_struct_return
&& POINTER_TYPE_P (type
)
2044 && upc_shared_type_p (TREE_TYPE (type
))
2045 && AGGREGATE_TYPE_P (upc_pts_rep_type_node
))
2048 if (targetm
.calls
.return_in_memory (type
, fntype
))
2051 /* Make sure we have suitable call-clobbered regs to return
2052 the value in; if not, we must return it in memory. */
2053 reg
= hard_function_value (type
, 0, fntype
, 0);
2055 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2060 regno
= REGNO (reg
);
2061 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
2062 for (i
= 0; i
< nregs
; i
++)
2063 if (! call_used_regs
[regno
+ i
])
2069 /* Return true if we should assign DECL a pseudo register; false if it
2070 should live on the local stack. */
2073 use_register_for_decl (const_tree decl
)
2075 if (!targetm
.calls
.allocate_stack_slots_for_args())
2078 /* Honor volatile. */
2079 if (TREE_SIDE_EFFECTS (decl
))
2082 /* Honor addressability. */
2083 if (TREE_ADDRESSABLE (decl
))
2086 /* Only register-like things go in registers. */
2087 if (DECL_MODE (decl
) == BLKmode
)
2090 /* If -ffloat-store specified, don't put explicit float variables
2092 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2093 propagates values across these stores, and it probably shouldn't. */
2094 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
2097 /* If we're not interested in tracking debugging information for
2098 this decl, then we can certainly put it in a register. */
2099 if (DECL_IGNORED_P (decl
))
2105 if (!DECL_REGISTER (decl
))
2108 switch (TREE_CODE (TREE_TYPE (decl
)))
2112 case QUAL_UNION_TYPE
:
2113 /* When not optimizing, disregard register keyword for variables with
2114 types containing methods, otherwise the methods won't be callable
2115 from the debugger. */
2116 if (TYPE_METHODS (TREE_TYPE (decl
)))
2126 /* Return true if TYPE should be passed by invisible reference. */
2129 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
2130 tree type
, bool named_arg
)
2134 /* If this type contains non-trivial constructors, then it is
2135 forbidden for the middle-end to create any new copies. */
2136 if (TREE_ADDRESSABLE (type
))
2139 /* GCC post 3.4 passes *all* variable sized types by reference. */
2140 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
2143 /* If a record type should be passed the same as its first (and only)
2144 member, use the type and mode of that member. */
2145 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2147 type
= TREE_TYPE (first_field (type
));
2148 mode
= TYPE_MODE (type
);
2152 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
2155 /* Return true if TYPE, which is passed by reference, should be callee
2156 copied instead of caller copied. */
2159 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
2160 tree type
, bool named_arg
)
2162 if (type
&& TREE_ADDRESSABLE (type
))
2164 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
2167 /* Structures to communicate between the subroutines of assign_parms.
2168 The first holds data persistent across all parameters, the second
2169 is cleared out for each parameter. */
2171 struct assign_parm_data_all
2173 CUMULATIVE_ARGS args_so_far
;
2174 struct args_size stack_args_size
;
2175 tree function_result_decl
;
2177 rtx first_conversion_insn
;
2178 rtx last_conversion_insn
;
2179 HOST_WIDE_INT pretend_args_size
;
2180 HOST_WIDE_INT extra_pretend_bytes
;
2181 int reg_parm_stack_space
;
2184 struct assign_parm_data_one
2190 enum machine_mode nominal_mode
;
2191 enum machine_mode passed_mode
;
2192 enum machine_mode promoted_mode
;
2193 struct locate_and_pad_arg_data locate
;
2195 BOOL_BITFIELD named_arg
: 1;
2196 BOOL_BITFIELD passed_pointer
: 1;
2197 BOOL_BITFIELD on_stack
: 1;
2198 BOOL_BITFIELD loaded_in_reg
: 1;
2201 /* A subroutine of assign_parms. Initialize ALL. */
2204 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2206 tree fntype ATTRIBUTE_UNUSED
;
2208 memset (all
, 0, sizeof (*all
));
2210 fntype
= TREE_TYPE (current_function_decl
);
2212 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2213 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
2215 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
2216 current_function_decl
, -1);
2219 #ifdef REG_PARM_STACK_SPACE
2220 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
2224 /* If ARGS contains entries with complex types, split the entry into two
2225 entries of the component type. Return a new list of substitutions are
2226 needed, else the old list. */
2229 split_complex_args (VEC(tree
, heap
) **args
)
2234 FOR_EACH_VEC_ELT (tree
, *args
, i
, p
)
2236 tree type
= TREE_TYPE (p
);
2237 if (TREE_CODE (type
) == COMPLEX_TYPE
2238 && targetm
.calls
.split_complex_arg (type
))
2241 tree subtype
= TREE_TYPE (type
);
2242 bool addressable
= TREE_ADDRESSABLE (p
);
2244 /* Rewrite the PARM_DECL's type with its component. */
2246 TREE_TYPE (p
) = subtype
;
2247 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2248 DECL_MODE (p
) = VOIDmode
;
2249 DECL_SIZE (p
) = NULL
;
2250 DECL_SIZE_UNIT (p
) = NULL
;
2251 /* If this arg must go in memory, put it in a pseudo here.
2252 We can't allow it to go in memory as per normal parms,
2253 because the usual place might not have the imag part
2254 adjacent to the real part. */
2255 DECL_ARTIFICIAL (p
) = addressable
;
2256 DECL_IGNORED_P (p
) = addressable
;
2257 TREE_ADDRESSABLE (p
) = 0;
2259 VEC_replace (tree
, *args
, i
, p
);
2261 /* Build a second synthetic decl. */
2262 decl
= build_decl (EXPR_LOCATION (p
),
2263 PARM_DECL
, NULL_TREE
, subtype
);
2264 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2265 DECL_ARTIFICIAL (decl
) = addressable
;
2266 DECL_IGNORED_P (decl
) = addressable
;
2267 layout_decl (decl
, 0);
2268 VEC_safe_insert (tree
, heap
, *args
, ++i
, decl
);
2273 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2274 the hidden struct return argument, and (abi willing) complex args.
2275 Return the new parameter list. */
2277 static VEC(tree
, heap
) *
2278 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2280 tree fndecl
= current_function_decl
;
2281 tree fntype
= TREE_TYPE (fndecl
);
2282 VEC(tree
, heap
) *fnargs
= NULL
;
2285 for (arg
= DECL_ARGUMENTS (fndecl
); arg
; arg
= DECL_CHAIN (arg
))
2286 VEC_safe_push (tree
, heap
, fnargs
, arg
);
2288 all
->orig_fnargs
= DECL_ARGUMENTS (fndecl
);
2290 /* If struct value address is treated as the first argument, make it so. */
2291 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2292 && ! cfun
->returns_pcc_struct
2293 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2295 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2298 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2299 PARM_DECL
, get_identifier (".result_ptr"), type
);
2300 DECL_ARG_TYPE (decl
) = type
;
2301 DECL_ARTIFICIAL (decl
) = 1;
2302 DECL_NAMELESS (decl
) = 1;
2303 TREE_CONSTANT (decl
) = 1;
2305 DECL_CHAIN (decl
) = all
->orig_fnargs
;
2306 all
->orig_fnargs
= decl
;
2307 VEC_safe_insert (tree
, heap
, fnargs
, 0, decl
);
2309 all
->function_result_decl
= decl
;
2312 /* If the target wants to split complex arguments into scalars, do so. */
2313 if (targetm
.calls
.split_complex_arg
)
2314 split_complex_args (&fnargs
);
2319 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2320 data for the parameter. Incorporate ABI specifics such as pass-by-
2321 reference and type promotion. */
2324 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2325 struct assign_parm_data_one
*data
)
2327 tree nominal_type
, passed_type
;
2328 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2331 memset (data
, 0, sizeof (*data
));
2333 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2335 data
->named_arg
= 1; /* No variadic parms. */
2336 else if (DECL_CHAIN (parm
))
2337 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2338 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2339 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2341 data
->named_arg
= 0; /* Treat as variadic. */
2343 nominal_type
= TREE_TYPE (parm
);
2344 passed_type
= DECL_ARG_TYPE (parm
);
2346 /* Look out for errors propagating this far. Also, if the parameter's
2347 type is void then its value doesn't matter. */
2348 if (TREE_TYPE (parm
) == error_mark_node
2349 /* This can happen after weird syntax errors
2350 or if an enum type is defined among the parms. */
2351 || TREE_CODE (parm
) != PARM_DECL
2352 || passed_type
== NULL
2353 || VOID_TYPE_P (nominal_type
))
2355 nominal_type
= passed_type
= void_type_node
;
2356 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2360 /* Find mode of arg as it is passed, and mode of arg as it should be
2361 during execution of this function. */
2362 passed_mode
= TYPE_MODE (passed_type
);
2363 nominal_mode
= TYPE_MODE (nominal_type
);
2365 /* If the parm is to be passed as a transparent union or record, use the
2366 type of the first field for the tests below. We have already verified
2367 that the modes are the same. */
2368 if ((TREE_CODE (passed_type
) == UNION_TYPE
2369 || TREE_CODE (passed_type
) == RECORD_TYPE
)
2370 && TYPE_TRANSPARENT_AGGR (passed_type
))
2371 passed_type
= TREE_TYPE (first_field (passed_type
));
2373 /* See if this arg was passed by invisible reference. */
2374 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2375 passed_type
, data
->named_arg
))
2377 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2378 data
->passed_pointer
= true;
2379 passed_mode
= nominal_mode
= Pmode
;
2382 /* Find mode as it is passed by the ABI. */
2383 unsignedp
= TYPE_UNSIGNED (passed_type
);
2384 promoted_mode
= promote_function_mode (passed_type
, passed_mode
, &unsignedp
,
2385 TREE_TYPE (current_function_decl
), 0);
2388 data
->nominal_type
= nominal_type
;
2389 data
->passed_type
= passed_type
;
2390 data
->nominal_mode
= nominal_mode
;
2391 data
->passed_mode
= passed_mode
;
2392 data
->promoted_mode
= promoted_mode
;
2395 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2398 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2399 struct assign_parm_data_one
*data
, bool no_rtl
)
2401 int varargs_pretend_bytes
= 0;
2403 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2404 data
->promoted_mode
,
2406 &varargs_pretend_bytes
, no_rtl
);
2408 /* If the back-end has requested extra stack space, record how much is
2409 needed. Do not change pretend_args_size otherwise since it may be
2410 nonzero from an earlier partial argument. */
2411 if (varargs_pretend_bytes
> 0)
2412 all
->pretend_args_size
= varargs_pretend_bytes
;
2415 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2416 the incoming location of the current parameter. */
2419 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2420 struct assign_parm_data_one
*data
)
2422 HOST_WIDE_INT pretend_bytes
= 0;
2426 if (data
->promoted_mode
== VOIDmode
)
2428 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2432 entry_parm
= targetm
.calls
.function_incoming_arg (&all
->args_so_far
,
2433 data
->promoted_mode
,
2437 if (entry_parm
== 0)
2438 data
->promoted_mode
= data
->passed_mode
;
2440 /* Determine parm's home in the stack, in case it arrives in the stack
2441 or we should pretend it did. Compute the stack position and rtx where
2442 the argument arrives and its size.
2444 There is one complexity here: If this was a parameter that would
2445 have been passed in registers, but wasn't only because it is
2446 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2447 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2448 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2449 as it was the previous time. */
2450 in_regs
= entry_parm
!= 0;
2451 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2454 if (!in_regs
&& !data
->named_arg
)
2456 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2459 tem
= targetm
.calls
.function_incoming_arg (&all
->args_so_far
,
2460 data
->promoted_mode
,
2461 data
->passed_type
, true);
2462 in_regs
= tem
!= NULL
;
2466 /* If this parameter was passed both in registers and in the stack, use
2467 the copy on the stack. */
2468 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2476 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2477 data
->promoted_mode
,
2480 data
->partial
= partial
;
2482 /* The caller might already have allocated stack space for the
2483 register parameters. */
2484 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2486 /* Part of this argument is passed in registers and part
2487 is passed on the stack. Ask the prologue code to extend
2488 the stack part so that we can recreate the full value.
2490 PRETEND_BYTES is the size of the registers we need to store.
2491 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2492 stack space that the prologue should allocate.
2494 Internally, gcc assumes that the argument pointer is aligned
2495 to STACK_BOUNDARY bits. This is used both for alignment
2496 optimizations (see init_emit) and to locate arguments that are
2497 aligned to more than PARM_BOUNDARY bits. We must preserve this
2498 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2499 a stack boundary. */
2501 /* We assume at most one partial arg, and it must be the first
2502 argument on the stack. */
2503 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2505 pretend_bytes
= partial
;
2506 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2508 /* We want to align relative to the actual stack pointer, so
2509 don't include this in the stack size until later. */
2510 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2514 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2515 entry_parm
? data
->partial
: 0, current_function_decl
,
2516 &all
->stack_args_size
, &data
->locate
);
2518 /* Update parm_stack_boundary if this parameter is passed in the
2520 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2521 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2523 /* Adjust offsets to include the pretend args. */
2524 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2525 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2526 data
->locate
.offset
.constant
+= pretend_bytes
;
2528 data
->entry_parm
= entry_parm
;
2531 /* A subroutine of assign_parms. If there is actually space on the stack
2532 for this parm, count it in stack_args_size and return true. */
2535 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2536 struct assign_parm_data_one
*data
)
2538 /* Trivially true if we've no incoming register. */
2539 if (data
->entry_parm
== NULL
)
2541 /* Also true if we're partially in registers and partially not,
2542 since we've arranged to drop the entire argument on the stack. */
2543 else if (data
->partial
!= 0)
2545 /* Also true if the target says that it's passed in both registers
2546 and on the stack. */
2547 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2548 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2550 /* Also true if the target says that there's stack allocated for
2551 all register parameters. */
2552 else if (all
->reg_parm_stack_space
> 0)
2554 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2558 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2559 if (data
->locate
.size
.var
)
2560 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2565 /* A subroutine of assign_parms. Given that this parameter is allocated
2566 stack space by the ABI, find it. */
2569 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2571 rtx offset_rtx
, stack_parm
;
2572 unsigned int align
, boundary
;
2574 /* If we're passing this arg using a reg, make its stack home the
2575 aligned stack slot. */
2576 if (data
->entry_parm
)
2577 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2579 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2581 stack_parm
= crtl
->args
.internal_arg_pointer
;
2582 if (offset_rtx
!= const0_rtx
)
2583 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2584 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2586 if (!data
->passed_pointer
)
2588 set_mem_attributes (stack_parm
, parm
, 1);
2589 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2590 while promoted mode's size is needed. */
2591 if (data
->promoted_mode
!= BLKmode
2592 && data
->promoted_mode
!= DECL_MODE (parm
))
2594 set_mem_size (stack_parm
,
2595 GEN_INT (GET_MODE_SIZE (data
->promoted_mode
)));
2596 if (MEM_EXPR (stack_parm
) && MEM_OFFSET (stack_parm
))
2598 int offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2599 data
->promoted_mode
);
2601 set_mem_offset (stack_parm
,
2602 plus_constant (MEM_OFFSET (stack_parm
),
2608 boundary
= data
->locate
.boundary
;
2609 align
= BITS_PER_UNIT
;
2611 /* If we're padding upward, we know that the alignment of the slot
2612 is TARGET_FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2613 intentionally forcing upward padding. Otherwise we have to come
2614 up with a guess at the alignment based on OFFSET_RTX. */
2615 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2617 else if (CONST_INT_P (offset_rtx
))
2619 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2620 align
= align
& -align
;
2622 set_mem_align (stack_parm
, align
);
2624 if (data
->entry_parm
)
2625 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2627 data
->stack_parm
= stack_parm
;
2630 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2631 always valid and contiguous. */
2634 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2636 rtx entry_parm
= data
->entry_parm
;
2637 rtx stack_parm
= data
->stack_parm
;
2639 /* If this parm was passed part in regs and part in memory, pretend it
2640 arrived entirely in memory by pushing the register-part onto the stack.
2641 In the special case of a DImode or DFmode that is split, we could put
2642 it together in a pseudoreg directly, but for now that's not worth
2644 if (data
->partial
!= 0)
2646 /* Handle calls that pass values in multiple non-contiguous
2647 locations. The Irix 6 ABI has examples of this. */
2648 if (GET_CODE (entry_parm
) == PARALLEL
)
2649 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2651 int_size_in_bytes (data
->passed_type
));
2654 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2655 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2656 data
->partial
/ UNITS_PER_WORD
);
2659 entry_parm
= stack_parm
;
2662 /* If we didn't decide this parm came in a register, by default it came
2664 else if (entry_parm
== NULL
)
2665 entry_parm
= stack_parm
;
2667 /* When an argument is passed in multiple locations, we can't make use
2668 of this information, but we can save some copying if the whole argument
2669 is passed in a single register. */
2670 else if (GET_CODE (entry_parm
) == PARALLEL
2671 && data
->nominal_mode
!= BLKmode
2672 && data
->passed_mode
!= BLKmode
)
2674 size_t i
, len
= XVECLEN (entry_parm
, 0);
2676 for (i
= 0; i
< len
; i
++)
2677 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2678 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2679 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2680 == data
->passed_mode
)
2681 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2683 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2688 data
->entry_parm
= entry_parm
;
2691 /* A subroutine of assign_parms. Reconstitute any values which were
2692 passed in multiple registers and would fit in a single register. */
2695 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2697 rtx entry_parm
= data
->entry_parm
;
2699 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2700 This can be done with register operations rather than on the
2701 stack, even if we will store the reconstituted parameter on the
2703 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2705 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2706 emit_group_store (parmreg
, entry_parm
, data
->passed_type
,
2707 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2708 entry_parm
= parmreg
;
2711 data
->entry_parm
= entry_parm
;
2714 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2715 always valid and properly aligned. */
2718 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2720 rtx stack_parm
= data
->stack_parm
;
2722 /* If we can't trust the parm stack slot to be aligned enough for its
2723 ultimate type, don't use that slot after entry. We'll make another
2724 stack slot, if we need one. */
2726 && ((STRICT_ALIGNMENT
2727 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2728 || (data
->nominal_type
2729 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2730 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2733 /* If parm was passed in memory, and we need to convert it on entry,
2734 don't store it back in that same slot. */
2735 else if (data
->entry_parm
== stack_parm
2736 && data
->nominal_mode
!= BLKmode
2737 && data
->nominal_mode
!= data
->passed_mode
)
2740 /* If stack protection is in effect for this function, don't leave any
2741 pointers in their passed stack slots. */
2742 else if (crtl
->stack_protect_guard
2743 && (flag_stack_protect
== 2
2744 || data
->passed_pointer
2745 || POINTER_TYPE_P (data
->nominal_type
)))
2748 data
->stack_parm
= stack_parm
;
2751 /* A subroutine of assign_parms. Return true if the current parameter
2752 should be stored as a BLKmode in the current frame. */
2755 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2757 if (data
->nominal_mode
== BLKmode
)
2759 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2762 #ifdef BLOCK_REG_PADDING
2763 /* Only assign_parm_setup_block knows how to deal with register arguments
2764 that are padded at the least significant end. */
2765 if (REG_P (data
->entry_parm
)
2766 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2767 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2768 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2775 /* A subroutine of assign_parms. Arrange for the parameter to be
2776 present and valid in DATA->STACK_RTL. */
2779 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2780 tree parm
, struct assign_parm_data_one
*data
)
2782 rtx entry_parm
= data
->entry_parm
;
2783 rtx stack_parm
= data
->stack_parm
;
2785 HOST_WIDE_INT size_stored
;
2787 if (GET_CODE (entry_parm
) == PARALLEL
)
2788 entry_parm
= emit_group_move_into_temps (entry_parm
);
2790 size
= int_size_in_bytes (data
->passed_type
);
2791 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2792 if (stack_parm
== 0)
2794 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2795 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2797 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2798 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2799 set_mem_attributes (stack_parm
, parm
, 1);
2802 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2803 calls that pass values in multiple non-contiguous locations. */
2804 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2808 /* Note that we will be storing an integral number of words.
2809 So we have to be careful to ensure that we allocate an
2810 integral number of words. We do this above when we call
2811 assign_stack_local if space was not allocated in the argument
2812 list. If it was, this will not work if PARM_BOUNDARY is not
2813 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2814 if it becomes a problem. Exception is when BLKmode arrives
2815 with arguments not conforming to word_mode. */
2817 if (data
->stack_parm
== 0)
2819 else if (GET_CODE (entry_parm
) == PARALLEL
)
2822 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2824 mem
= validize_mem (stack_parm
);
2826 /* Handle values in multiple non-contiguous locations. */
2827 if (GET_CODE (entry_parm
) == PARALLEL
)
2829 push_to_sequence2 (all
->first_conversion_insn
,
2830 all
->last_conversion_insn
);
2831 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2832 all
->first_conversion_insn
= get_insns ();
2833 all
->last_conversion_insn
= get_last_insn ();
2840 /* If SIZE is that of a mode no bigger than a word, just use
2841 that mode's store operation. */
2842 else if (size
<= UNITS_PER_WORD
)
2844 enum machine_mode mode
2845 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2848 #ifdef BLOCK_REG_PADDING
2849 && (size
== UNITS_PER_WORD
2850 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2851 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2857 /* We are really truncating a word_mode value containing
2858 SIZE bytes into a value of mode MODE. If such an
2859 operation requires no actual instructions, we can refer
2860 to the value directly in mode MODE, otherwise we must
2861 start with the register in word_mode and explicitly
2863 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2864 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2867 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2868 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2870 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2873 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2874 machine must be aligned to the left before storing
2875 to memory. Note that the previous test doesn't
2876 handle all cases (e.g. SIZE == 3). */
2877 else if (size
!= UNITS_PER_WORD
2878 #ifdef BLOCK_REG_PADDING
2879 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2887 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2888 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2890 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
, by
, NULL_RTX
, 1);
2891 tem
= change_address (mem
, word_mode
, 0);
2892 emit_move_insn (tem
, x
);
2895 move_block_from_reg (REGNO (entry_parm
), mem
,
2896 size_stored
/ UNITS_PER_WORD
);
2899 move_block_from_reg (REGNO (entry_parm
), mem
,
2900 size_stored
/ UNITS_PER_WORD
);
2902 else if (data
->stack_parm
== 0)
2904 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2905 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2907 all
->first_conversion_insn
= get_insns ();
2908 all
->last_conversion_insn
= get_last_insn ();
2912 data
->stack_parm
= stack_parm
;
2913 SET_DECL_RTL (parm
, stack_parm
);
2916 /* A subroutine of assign_parm_setup_reg, called through note_stores.
2917 This collects sets and clobbers of hard registers in a HARD_REG_SET,
2918 which is pointed to by DATA. */
2920 record_hard_reg_sets (rtx x
, const_rtx pat ATTRIBUTE_UNUSED
, void *data
)
2922 HARD_REG_SET
*pset
= (HARD_REG_SET
*)data
;
2923 if (REG_P (x
) && HARD_REGISTER_P (x
))
2924 add_to_hard_reg_set (pset
, GET_MODE (x
), REGNO (x
));
2927 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2928 parameter. Get it there. Perform all ABI specified conversions. */
2931 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2932 struct assign_parm_data_one
*data
)
2934 rtx parmreg
, validated_mem
;
2935 rtx equiv_stack_parm
;
2936 enum machine_mode promoted_nominal_mode
;
2937 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2938 bool did_conversion
= false;
2939 bool need_conversion
, moved
;
2941 /* Store the parm in a pseudoregister during the function, but we may
2942 need to do it in a wider mode. Using 2 here makes the result
2943 consistent with promote_decl_mode and thus expand_expr_real_1. */
2944 promoted_nominal_mode
2945 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
2946 TREE_TYPE (current_function_decl
), 2);
2948 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2950 if (!DECL_ARTIFICIAL (parm
))
2951 mark_user_reg (parmreg
);
2953 /* If this was an item that we received a pointer to,
2954 set DECL_RTL appropriately. */
2955 if (data
->passed_pointer
)
2957 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2958 set_mem_attributes (x
, parm
, 1);
2959 SET_DECL_RTL (parm
, x
);
2962 SET_DECL_RTL (parm
, parmreg
);
2964 assign_parm_remove_parallels (data
);
2966 /* Copy the value into the register, thus bridging between
2967 assign_parm_find_data_types and expand_expr_real_1. */
2969 equiv_stack_parm
= data
->stack_parm
;
2970 validated_mem
= validize_mem (data
->entry_parm
);
2972 need_conversion
= (data
->nominal_mode
!= data
->passed_mode
2973 || promoted_nominal_mode
!= data
->promoted_mode
);
2977 && GET_MODE_CLASS (data
->nominal_mode
) == MODE_INT
2978 && data
->nominal_mode
== data
->passed_mode
2979 && data
->nominal_mode
== GET_MODE (data
->entry_parm
))
2981 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2982 mode, by the caller. We now have to convert it to
2983 NOMINAL_MODE, if different. However, PARMREG may be in
2984 a different mode than NOMINAL_MODE if it is being stored
2987 If ENTRY_PARM is a hard register, it might be in a register
2988 not valid for operating in its mode (e.g., an odd-numbered
2989 register for a DFmode). In that case, moves are the only
2990 thing valid, so we can't do a convert from there. This
2991 occurs when the calling sequence allow such misaligned
2994 In addition, the conversion may involve a call, which could
2995 clobber parameters which haven't been copied to pseudo
2998 First, we try to emit an insn which performs the necessary
2999 conversion. We verify that this insn does not clobber any
3002 enum insn_code icode
;
3005 icode
= can_extend_p (promoted_nominal_mode
, data
->passed_mode
,
3009 op1
= validated_mem
;
3010 if (icode
!= CODE_FOR_nothing
3011 && insn_operand_matches (icode
, 0, op0
)
3012 && insn_operand_matches (icode
, 1, op1
))
3014 enum rtx_code code
= unsignedp
? ZERO_EXTEND
: SIGN_EXTEND
;
3016 HARD_REG_SET hardregs
;
3019 insn
= gen_extend_insn (op0
, op1
, promoted_nominal_mode
,
3020 data
->passed_mode
, unsignedp
);
3022 insns
= get_insns ();
3025 CLEAR_HARD_REG_SET (hardregs
);
3026 for (insn
= insns
; insn
&& moved
; insn
= NEXT_INSN (insn
))
3029 note_stores (PATTERN (insn
), record_hard_reg_sets
,
3031 if (!hard_reg_set_empty_p (hardregs
))
3040 if (equiv_stack_parm
!= NULL_RTX
)
3041 equiv_stack_parm
= gen_rtx_fmt_e (code
, GET_MODE (parmreg
),
3048 /* Nothing to do. */
3050 else if (need_conversion
)
3052 /* We did not have an insn to convert directly, or the sequence
3053 generated appeared unsafe. We must first copy the parm to a
3054 pseudo reg, and save the conversion until after all
3055 parameters have been moved. */
3058 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3060 emit_move_insn (tempreg
, validated_mem
);
3062 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3063 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
3065 if (GET_CODE (tempreg
) == SUBREG
3066 && GET_MODE (tempreg
) == data
->nominal_mode
3067 && REG_P (SUBREG_REG (tempreg
))
3068 && data
->nominal_mode
== data
->passed_mode
3069 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
3070 && GET_MODE_SIZE (GET_MODE (tempreg
))
3071 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
3073 /* The argument is already sign/zero extended, so note it
3075 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
3076 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
3079 /* TREE_USED gets set erroneously during expand_assignment. */
3080 save_tree_used
= TREE_USED (parm
);
3081 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
3082 TREE_USED (parm
) = save_tree_used
;
3083 all
->first_conversion_insn
= get_insns ();
3084 all
->last_conversion_insn
= get_last_insn ();
3087 did_conversion
= true;
3090 emit_move_insn (parmreg
, validated_mem
);
3092 /* If we were passed a pointer but the actual value can safely live
3093 in a register, put it in one. */
3094 if (data
->passed_pointer
3095 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
3096 /* If by-reference argument was promoted, demote it. */
3097 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
3098 || use_register_for_decl (parm
)))
3100 /* We can't use nominal_mode, because it will have been set to
3101 Pmode above. We must use the actual mode of the parm. */
3102 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
3103 mark_user_reg (parmreg
);
3105 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
3107 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
3108 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
3110 push_to_sequence2 (all
->first_conversion_insn
,
3111 all
->last_conversion_insn
);
3112 emit_move_insn (tempreg
, DECL_RTL (parm
));
3113 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
3114 emit_move_insn (parmreg
, tempreg
);
3115 all
->first_conversion_insn
= get_insns ();
3116 all
->last_conversion_insn
= get_last_insn ();
3119 did_conversion
= true;
3122 emit_move_insn (parmreg
, DECL_RTL (parm
));
3124 SET_DECL_RTL (parm
, parmreg
);
3126 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3128 data
->stack_parm
= NULL
;
3131 /* Mark the register as eliminable if we did no conversion and it was
3132 copied from memory at a fixed offset, and the arg pointer was not
3133 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3134 offset formed an invalid address, such memory-equivalences as we
3135 make here would screw up life analysis for it. */
3136 if (data
->nominal_mode
== data
->passed_mode
3138 && data
->stack_parm
!= 0
3139 && MEM_P (data
->stack_parm
)
3140 && data
->locate
.offset
.var
== 0
3141 && reg_mentioned_p (virtual_incoming_args_rtx
,
3142 XEXP (data
->stack_parm
, 0)))
3144 rtx linsn
= get_last_insn ();
3147 /* Mark complex types separately. */
3148 if (GET_CODE (parmreg
) == CONCAT
)
3150 enum machine_mode submode
3151 = GET_MODE_INNER (GET_MODE (parmreg
));
3152 int regnor
= REGNO (XEXP (parmreg
, 0));
3153 int regnoi
= REGNO (XEXP (parmreg
, 1));
3154 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
3155 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
3156 GET_MODE_SIZE (submode
));
3158 /* Scan backwards for the set of the real and
3160 for (sinsn
= linsn
; sinsn
!= 0;
3161 sinsn
= prev_nonnote_insn (sinsn
))
3163 set
= single_set (sinsn
);
3167 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
3168 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
3169 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
3170 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
3173 else if ((set
= single_set (linsn
)) != 0
3174 && SET_DEST (set
) == parmreg
)
3175 set_unique_reg_note (linsn
, REG_EQUIV
, equiv_stack_parm
);
3178 /* For pointer data type, suggest pointer register. */
3179 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
3180 mark_reg_pointer (parmreg
,
3181 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
3184 /* A subroutine of assign_parms. Allocate stack space to hold the current
3185 parameter. Get it there. Perform all ABI specified conversions. */
3188 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
3189 struct assign_parm_data_one
*data
)
3191 /* Value must be stored in the stack slot STACK_PARM during function
3193 bool to_conversion
= false;
3195 assign_parm_remove_parallels (data
);
3197 if (data
->promoted_mode
!= data
->nominal_mode
)
3199 /* Conversion is required. */
3200 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3202 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
3204 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3205 to_conversion
= true;
3207 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
3208 TYPE_UNSIGNED (TREE_TYPE (parm
)));
3210 if (data
->stack_parm
)
3212 int offset
= subreg_lowpart_offset (data
->nominal_mode
,
3213 GET_MODE (data
->stack_parm
));
3214 /* ??? This may need a big-endian conversion on sparc64. */
3216 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
3217 if (offset
&& MEM_OFFSET (data
->stack_parm
))
3218 set_mem_offset (data
->stack_parm
,
3219 plus_constant (MEM_OFFSET (data
->stack_parm
),
3224 if (data
->entry_parm
!= data
->stack_parm
)
3228 if (data
->stack_parm
== 0)
3230 int align
= STACK_SLOT_ALIGNMENT (data
->passed_type
,
3231 GET_MODE (data
->entry_parm
),
3232 TYPE_ALIGN (data
->passed_type
));
3234 = assign_stack_local (GET_MODE (data
->entry_parm
),
3235 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3237 set_mem_attributes (data
->stack_parm
, parm
, 1);
3240 dest
= validize_mem (data
->stack_parm
);
3241 src
= validize_mem (data
->entry_parm
);
3245 /* Use a block move to handle potentially misaligned entry_parm. */
3247 push_to_sequence2 (all
->first_conversion_insn
,
3248 all
->last_conversion_insn
);
3249 to_conversion
= true;
3251 emit_block_move (dest
, src
,
3252 GEN_INT (int_size_in_bytes (data
->passed_type
)),
3256 emit_move_insn (dest
, src
);
3261 all
->first_conversion_insn
= get_insns ();
3262 all
->last_conversion_insn
= get_last_insn ();
3266 SET_DECL_RTL (parm
, data
->stack_parm
);
3269 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3270 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3273 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
,
3274 VEC(tree
, heap
) *fnargs
)
3277 tree orig_fnargs
= all
->orig_fnargs
;
3280 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
), ++i
)
3282 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3283 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3285 rtx tmp
, real
, imag
;
3286 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3288 real
= DECL_RTL (VEC_index (tree
, fnargs
, i
));
3289 imag
= DECL_RTL (VEC_index (tree
, fnargs
, i
+ 1));
3290 if (inner
!= GET_MODE (real
))
3292 real
= gen_lowpart_SUBREG (inner
, real
);
3293 imag
= gen_lowpart_SUBREG (inner
, imag
);
3296 if (TREE_ADDRESSABLE (parm
))
3299 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3300 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3302 TYPE_ALIGN (TREE_TYPE (parm
)));
3304 /* split_complex_arg put the real and imag parts in
3305 pseudos. Move them to memory. */
3306 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3307 set_mem_attributes (tmp
, parm
, 1);
3308 rmem
= adjust_address_nv (tmp
, inner
, 0);
3309 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3310 push_to_sequence2 (all
->first_conversion_insn
,
3311 all
->last_conversion_insn
);
3312 emit_move_insn (rmem
, real
);
3313 emit_move_insn (imem
, imag
);
3314 all
->first_conversion_insn
= get_insns ();
3315 all
->last_conversion_insn
= get_last_insn ();
3319 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3320 SET_DECL_RTL (parm
, tmp
);
3322 real
= DECL_INCOMING_RTL (VEC_index (tree
, fnargs
, i
));
3323 imag
= DECL_INCOMING_RTL (VEC_index (tree
, fnargs
, i
+ 1));
3324 if (inner
!= GET_MODE (real
))
3326 real
= gen_lowpart_SUBREG (inner
, real
);
3327 imag
= gen_lowpart_SUBREG (inner
, imag
);
3329 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3330 set_decl_incoming_rtl (parm
, tmp
, false);
3336 /* Assign RTL expressions to the function's parameters. This may involve
3337 copying them into registers and using those registers as the DECL_RTL. */
3340 assign_parms (tree fndecl
)
3342 struct assign_parm_data_all all
;
3344 VEC(tree
, heap
) *fnargs
;
3347 crtl
->args
.internal_arg_pointer
3348 = targetm
.calls
.internal_arg_pointer ();
3350 assign_parms_initialize_all (&all
);
3351 fnargs
= assign_parms_augmented_arg_list (&all
);
3353 FOR_EACH_VEC_ELT (tree
, fnargs
, i
, parm
)
3355 struct assign_parm_data_one data
;
3357 /* Extract the type of PARM; adjust it according to ABI. */
3358 assign_parm_find_data_types (&all
, parm
, &data
);
3360 /* Early out for errors and void parameters. */
3361 if (data
.passed_mode
== VOIDmode
)
3363 SET_DECL_RTL (parm
, const0_rtx
);
3364 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3368 /* Estimate stack alignment from parameter alignment. */
3369 if (SUPPORTS_STACK_ALIGNMENT
)
3372 = targetm
.calls
.function_arg_boundary (data
.promoted_mode
,
3374 align
= MINIMUM_ALIGNMENT (data
.passed_type
, data
.promoted_mode
,
3376 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3377 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3378 TYPE_MODE (data
.nominal_type
),
3379 TYPE_ALIGN (data
.nominal_type
));
3380 if (crtl
->stack_alignment_estimated
< align
)
3382 gcc_assert (!crtl
->stack_realign_processed
);
3383 crtl
->stack_alignment_estimated
= align
;
3387 if (cfun
->stdarg
&& !DECL_CHAIN (parm
))
3388 assign_parms_setup_varargs (&all
, &data
, false);
3390 /* Find out where the parameter arrives in this function. */
3391 assign_parm_find_entry_rtl (&all
, &data
);
3393 /* Find out where stack space for this parameter might be. */
3394 if (assign_parm_is_stack_parm (&all
, &data
))
3396 assign_parm_find_stack_rtl (parm
, &data
);
3397 assign_parm_adjust_entry_rtl (&data
);
3400 /* Record permanently how this parm was passed. */
3401 if (data
.passed_pointer
)
3404 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
.passed_type
)),
3406 set_decl_incoming_rtl (parm
, incoming_rtl
, true);
3409 set_decl_incoming_rtl (parm
, data
.entry_parm
, false);
3411 /* Update info on where next arg arrives in registers. */
3412 targetm
.calls
.function_arg_advance (&all
.args_so_far
, data
.promoted_mode
,
3413 data
.passed_type
, data
.named_arg
);
3415 assign_parm_adjust_stack_rtl (&data
);
3417 if (assign_parm_setup_block_p (&data
))
3418 assign_parm_setup_block (&all
, parm
, &data
);
3419 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3420 assign_parm_setup_reg (&all
, parm
, &data
);
3422 assign_parm_setup_stack (&all
, parm
, &data
);
3425 if (targetm
.calls
.split_complex_arg
)
3426 assign_parms_unsplit_complex (&all
, fnargs
);
3428 VEC_free (tree
, heap
, fnargs
);
3430 /* Output all parameter conversion instructions (possibly including calls)
3431 now that all parameters have been copied out of hard registers. */
3432 emit_insn (all
.first_conversion_insn
);
3434 /* Estimate reload stack alignment from scalar return mode. */
3435 if (SUPPORTS_STACK_ALIGNMENT
)
3437 if (DECL_RESULT (fndecl
))
3439 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3440 enum machine_mode mode
= TYPE_MODE (type
);
3444 && !AGGREGATE_TYPE_P (type
))
3446 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3447 if (crtl
->stack_alignment_estimated
< align
)
3449 gcc_assert (!crtl
->stack_realign_processed
);
3450 crtl
->stack_alignment_estimated
= align
;
3456 /* If we are receiving a struct value address as the first argument, set up
3457 the RTL for the function result. As this might require code to convert
3458 the transmitted address to Pmode, we do this here to ensure that possible
3459 preliminary conversions of the address have been emitted already. */
3460 if (all
.function_result_decl
)
3462 tree result
= DECL_RESULT (current_function_decl
);
3463 rtx addr
= DECL_RTL (all
.function_result_decl
);
3466 if (DECL_BY_REFERENCE (result
))
3468 SET_DECL_VALUE_EXPR (result
, all
.function_result_decl
);
3473 SET_DECL_VALUE_EXPR (result
,
3474 build1 (INDIRECT_REF
, TREE_TYPE (result
),
3475 all
.function_result_decl
));
3476 addr
= convert_memory_address (Pmode
, addr
);
3477 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3478 set_mem_attributes (x
, result
, 1);
3481 DECL_HAS_VALUE_EXPR_P (result
) = 1;
3483 SET_DECL_RTL (result
, x
);
3486 /* We have aligned all the args, so add space for the pretend args. */
3487 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3488 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3489 crtl
->args
.size
= all
.stack_args_size
.constant
;
3491 /* Adjust function incoming argument size for alignment and
3494 #ifdef REG_PARM_STACK_SPACE
3495 crtl
->args
.size
= MAX (crtl
->args
.size
,
3496 REG_PARM_STACK_SPACE (fndecl
));
3499 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3500 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3502 #ifdef ARGS_GROW_DOWNWARD
3503 crtl
->args
.arg_offset_rtx
3504 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3505 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3506 size_int (-all
.stack_args_size
.constant
)),
3507 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3509 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3512 /* See how many bytes, if any, of its args a function should try to pop
3515 crtl
->args
.pops_args
= targetm
.calls
.return_pops_args (fndecl
,
3519 /* For stdarg.h function, save info about
3520 regs and stack space used by the named args. */
3522 crtl
->args
.info
= all
.args_so_far
;
3524 /* Set the rtx used for the function return value. Put this in its
3525 own variable so any optimizers that need this information don't have
3526 to include tree.h. Do this here so it gets done when an inlined
3527 function gets output. */
3530 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3531 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3533 /* If scalar return value was computed in a pseudo-reg, or was a named
3534 return value that got dumped to the stack, copy that to the hard
3536 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3538 tree decl_result
= DECL_RESULT (fndecl
);
3539 rtx decl_rtl
= DECL_RTL (decl_result
);
3541 if (REG_P (decl_rtl
)
3542 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3543 : DECL_REGISTER (decl_result
))
3547 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3549 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3550 /* The delay slot scheduler assumes that crtl->return_rtx
3551 holds the hard register containing the return value, not a
3552 temporary pseudo. */
3553 crtl
->return_rtx
= real_decl_rtl
;
3558 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3559 For all seen types, gimplify their sizes. */
3562 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3569 if (POINTER_TYPE_P (t
))
3571 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3572 && !TYPE_SIZES_GIMPLIFIED (t
))
3574 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3582 /* Gimplify the parameter list for current_function_decl. This involves
3583 evaluating SAVE_EXPRs of variable sized parameters and generating code
3584 to implement callee-copies reference parameters. Returns a sequence of
3585 statements to add to the beginning of the function. */
3588 gimplify_parameters (void)
3590 struct assign_parm_data_all all
;
3592 gimple_seq stmts
= NULL
;
3593 VEC(tree
, heap
) *fnargs
;
3596 assign_parms_initialize_all (&all
);
3597 fnargs
= assign_parms_augmented_arg_list (&all
);
3599 FOR_EACH_VEC_ELT (tree
, fnargs
, i
, parm
)
3601 struct assign_parm_data_one data
;
3603 /* Extract the type of PARM; adjust it according to ABI. */
3604 assign_parm_find_data_types (&all
, parm
, &data
);
3606 /* Early out for errors and void parameters. */
3607 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3610 /* Update info on where next arg arrives in registers. */
3611 targetm
.calls
.function_arg_advance (&all
.args_so_far
, data
.promoted_mode
,
3612 data
.passed_type
, data
.named_arg
);
3614 /* ??? Once upon a time variable_size stuffed parameter list
3615 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3616 turned out to be less than manageable in the gimple world.
3617 Now we have to hunt them down ourselves. */
3618 walk_tree_without_duplicates (&data
.passed_type
,
3619 gimplify_parm_type
, &stmts
);
3621 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3623 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3624 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3627 if (data
.passed_pointer
)
3629 tree type
= TREE_TYPE (data
.passed_type
);
3630 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3631 type
, data
.named_arg
))
3635 /* For constant-sized objects, this is trivial; for
3636 variable-sized objects, we have to play games. */
3637 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3638 && !(flag_stack_check
== GENERIC_STACK_CHECK
3639 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3640 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3642 local
= create_tmp_reg (type
, get_name (parm
));
3643 DECL_IGNORED_P (local
) = 0;
3644 /* If PARM was addressable, move that flag over
3645 to the local copy, as its address will be taken,
3646 not the PARMs. Keep the parms address taken
3647 as we'll query that flag during gimplification. */
3648 if (TREE_ADDRESSABLE (parm
))
3649 TREE_ADDRESSABLE (local
) = 1;
3653 tree ptr_type
, addr
;
3655 ptr_type
= build_pointer_type (type
);
3656 addr
= create_tmp_reg (ptr_type
, get_name (parm
));
3657 DECL_IGNORED_P (addr
) = 0;
3658 local
= build_fold_indirect_ref (addr
);
3660 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3661 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3662 /* The call has been built for a variable-sized object. */
3663 CALL_ALLOCA_FOR_VAR_P (t
) = 1;
3664 t
= fold_convert (ptr_type
, t
);
3665 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3666 gimplify_and_add (t
, &stmts
);
3669 gimplify_assign (local
, parm
, &stmts
);
3671 SET_DECL_VALUE_EXPR (parm
, local
);
3672 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3677 VEC_free (tree
, heap
, fnargs
);
3682 /* Compute the size and offset from the start of the stacked arguments for a
3683 parm passed in mode PASSED_MODE and with type TYPE.
3685 INITIAL_OFFSET_PTR points to the current offset into the stacked
3688 The starting offset and size for this parm are returned in
3689 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3690 nonzero, the offset is that of stack slot, which is returned in
3691 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3692 padding required from the initial offset ptr to the stack slot.
3694 IN_REGS is nonzero if the argument will be passed in registers. It will
3695 never be set if REG_PARM_STACK_SPACE is not defined.
3697 FNDECL is the function in which the argument was defined.
3699 There are two types of rounding that are done. The first, controlled by
3700 TARGET_FUNCTION_ARG_BOUNDARY, forces the offset from the start of the
3701 argument list to be aligned to the specific boundary (in bits). This
3702 rounding affects the initial and starting offsets, but not the argument
3705 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3706 optionally rounds the size of the parm to PARM_BOUNDARY. The
3707 initial offset is not affected by this rounding, while the size always
3708 is and the starting offset may be. */
3710 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3711 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3712 callers pass in the total size of args so far as
3713 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3716 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3717 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3718 struct args_size
*initial_offset_ptr
,
3719 struct locate_and_pad_arg_data
*locate
)
3722 enum direction where_pad
;
3723 unsigned int boundary
;
3724 int reg_parm_stack_space
= 0;
3725 int part_size_in_regs
;
3727 #ifdef REG_PARM_STACK_SPACE
3728 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3730 /* If we have found a stack parm before we reach the end of the
3731 area reserved for registers, skip that area. */
3734 if (reg_parm_stack_space
> 0)
3736 if (initial_offset_ptr
->var
)
3738 initial_offset_ptr
->var
3739 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3740 ssize_int (reg_parm_stack_space
));
3741 initial_offset_ptr
->constant
= 0;
3743 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3744 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3747 #endif /* REG_PARM_STACK_SPACE */
3749 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3752 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3753 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3754 boundary
= targetm
.calls
.function_arg_boundary (passed_mode
, type
);
3755 locate
->where_pad
= where_pad
;
3757 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3758 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3759 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3761 locate
->boundary
= boundary
;
3763 if (SUPPORTS_STACK_ALIGNMENT
)
3765 /* stack_alignment_estimated can't change after stack has been
3767 if (crtl
->stack_alignment_estimated
< boundary
)
3769 if (!crtl
->stack_realign_processed
)
3770 crtl
->stack_alignment_estimated
= boundary
;
3773 /* If stack is realigned and stack alignment value
3774 hasn't been finalized, it is OK not to increase
3775 stack_alignment_estimated. The bigger alignment
3776 requirement is recorded in stack_alignment_needed
3778 gcc_assert (!crtl
->stack_realign_finalized
3779 && crtl
->stack_realign_needed
);
3784 /* Remember if the outgoing parameter requires extra alignment on the
3785 calling function side. */
3786 if (crtl
->stack_alignment_needed
< boundary
)
3787 crtl
->stack_alignment_needed
= boundary
;
3788 if (crtl
->preferred_stack_boundary
< boundary
)
3789 crtl
->preferred_stack_boundary
= boundary
;
3791 #ifdef ARGS_GROW_DOWNWARD
3792 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3793 if (initial_offset_ptr
->var
)
3794 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3795 initial_offset_ptr
->var
);
3799 if (where_pad
!= none
3800 && (!host_integerp (sizetree
, 1)
3801 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3802 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3803 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3806 locate
->slot_offset
.constant
+= part_size_in_regs
;
3809 #ifdef REG_PARM_STACK_SPACE
3810 || REG_PARM_STACK_SPACE (fndecl
) > 0
3813 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3814 &locate
->alignment_pad
);
3816 locate
->size
.constant
= (-initial_offset_ptr
->constant
3817 - locate
->slot_offset
.constant
);
3818 if (initial_offset_ptr
->var
)
3819 locate
->size
.var
= size_binop (MINUS_EXPR
,
3820 size_binop (MINUS_EXPR
,
3822 initial_offset_ptr
->var
),
3823 locate
->slot_offset
.var
);
3825 /* Pad_below needs the pre-rounded size to know how much to pad
3827 locate
->offset
= locate
->slot_offset
;
3828 if (where_pad
== downward
)
3829 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3831 #else /* !ARGS_GROW_DOWNWARD */
3833 #ifdef REG_PARM_STACK_SPACE
3834 || REG_PARM_STACK_SPACE (fndecl
) > 0
3837 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3838 &locate
->alignment_pad
);
3839 locate
->slot_offset
= *initial_offset_ptr
;
3841 #ifdef PUSH_ROUNDING
3842 if (passed_mode
!= BLKmode
)
3843 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3846 /* Pad_below needs the pre-rounded size to know how much to pad below
3847 so this must be done before rounding up. */
3848 locate
->offset
= locate
->slot_offset
;
3849 if (where_pad
== downward
)
3850 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3852 if (where_pad
!= none
3853 && (!host_integerp (sizetree
, 1)
3854 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3855 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3857 ADD_PARM_SIZE (locate
->size
, sizetree
);
3859 locate
->size
.constant
-= part_size_in_regs
;
3860 #endif /* ARGS_GROW_DOWNWARD */
3862 #ifdef FUNCTION_ARG_OFFSET
3863 locate
->offset
.constant
+= FUNCTION_ARG_OFFSET (passed_mode
, type
);
3867 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3868 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3871 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3872 struct args_size
*alignment_pad
)
3874 tree save_var
= NULL_TREE
;
3875 HOST_WIDE_INT save_constant
= 0;
3876 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3877 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3879 #ifdef SPARC_STACK_BOUNDARY_HACK
3880 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3881 the real alignment of %sp. However, when it does this, the
3882 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3883 if (SPARC_STACK_BOUNDARY_HACK
)
3887 if (boundary
> PARM_BOUNDARY
)
3889 save_var
= offset_ptr
->var
;
3890 save_constant
= offset_ptr
->constant
;
3893 alignment_pad
->var
= NULL_TREE
;
3894 alignment_pad
->constant
= 0;
3896 if (boundary
> BITS_PER_UNIT
)
3898 if (offset_ptr
->var
)
3900 tree sp_offset_tree
= ssize_int (sp_offset
);
3901 tree offset
= size_binop (PLUS_EXPR
,
3902 ARGS_SIZE_TREE (*offset_ptr
),
3904 #ifdef ARGS_GROW_DOWNWARD
3905 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3907 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3910 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3911 /* ARGS_SIZE_TREE includes constant term. */
3912 offset_ptr
->constant
= 0;
3913 if (boundary
> PARM_BOUNDARY
)
3914 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3919 offset_ptr
->constant
= -sp_offset
+
3920 #ifdef ARGS_GROW_DOWNWARD
3921 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3923 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3925 if (boundary
> PARM_BOUNDARY
)
3926 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3932 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3934 if (passed_mode
!= BLKmode
)
3936 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3937 offset_ptr
->constant
3938 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3939 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3940 - GET_MODE_SIZE (passed_mode
));
3944 if (TREE_CODE (sizetree
) != INTEGER_CST
3945 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3947 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3948 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3950 ADD_PARM_SIZE (*offset_ptr
, s2
);
3951 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3957 /* True if register REGNO was alive at a place where `setjmp' was
3958 called and was set more than once or is an argument. Such regs may
3959 be clobbered by `longjmp'. */
3962 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3964 /* There appear to be cases where some local vars never reach the
3965 backend but have bogus regnos. */
3966 if (regno
>= max_reg_num ())
3969 return ((REG_N_SETS (regno
) > 1
3970 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3971 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3974 /* Walk the tree of blocks describing the binding levels within a
3975 function and warn about variables the might be killed by setjmp or
3976 vfork. This is done after calling flow_analysis before register
3977 allocation since that will clobber the pseudo-regs to hard
3981 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3985 for (decl
= BLOCK_VARS (block
); decl
; decl
= DECL_CHAIN (decl
))
3987 if (TREE_CODE (decl
) == VAR_DECL
3988 && DECL_RTL_SET_P (decl
)
3989 && REG_P (DECL_RTL (decl
))
3990 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3991 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3992 " %<longjmp%> or %<vfork%>", decl
);
3995 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3996 setjmp_vars_warning (setjmp_crosses
, sub
);
3999 /* Do the appropriate part of setjmp_vars_warning
4000 but for arguments instead of local variables. */
4003 setjmp_args_warning (bitmap setjmp_crosses
)
4006 for (decl
= DECL_ARGUMENTS (current_function_decl
);
4007 decl
; decl
= DECL_CHAIN (decl
))
4008 if (DECL_RTL (decl
) != 0
4009 && REG_P (DECL_RTL (decl
))
4010 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
4011 warning (OPT_Wclobbered
,
4012 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
4016 /* Generate warning messages for variables live across setjmp. */
4019 generate_setjmp_warnings (void)
4021 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
4023 if (n_basic_blocks
== NUM_FIXED_BLOCKS
4024 || bitmap_empty_p (setjmp_crosses
))
4027 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
4028 setjmp_args_warning (setjmp_crosses
);
4032 /* Reverse the order of elements in the fragment chain T of blocks,
4033 and return the new head of the chain (old last element). */
4036 block_fragments_nreverse (tree t
)
4038 tree prev
= 0, block
, next
;
4039 for (block
= t
; block
; block
= next
)
4041 next
= BLOCK_FRAGMENT_CHAIN (block
);
4042 BLOCK_FRAGMENT_CHAIN (block
) = prev
;
4048 /* Reverse the order of elements in the chain T of blocks,
4049 and return the new head of the chain (old last element).
4050 Also do the same on subblocks and reverse the order of elements
4051 in BLOCK_FRAGMENT_CHAIN as well. */
4054 blocks_nreverse_all (tree t
)
4056 tree prev
= 0, block
, next
;
4057 for (block
= t
; block
; block
= next
)
4059 next
= BLOCK_CHAIN (block
);
4060 BLOCK_CHAIN (block
) = prev
;
4061 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4062 if (BLOCK_FRAGMENT_CHAIN (block
)
4063 && BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
)
4064 BLOCK_FRAGMENT_CHAIN (block
)
4065 = block_fragments_nreverse (BLOCK_FRAGMENT_CHAIN (block
));
4072 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
4073 and create duplicate blocks. */
4074 /* ??? Need an option to either create block fragments or to create
4075 abstract origin duplicates of a source block. It really depends
4076 on what optimization has been performed. */
4079 reorder_blocks (void)
4081 tree block
= DECL_INITIAL (current_function_decl
);
4082 VEC(tree
,heap
) *block_stack
;
4084 if (block
== NULL_TREE
)
4087 block_stack
= VEC_alloc (tree
, heap
, 10);
4089 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
4090 clear_block_marks (block
);
4092 /* Prune the old trees away, so that they don't get in the way. */
4093 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
4094 BLOCK_CHAIN (block
) = NULL_TREE
;
4096 /* Recreate the block tree from the note nesting. */
4097 reorder_blocks_1 (get_insns (), block
, &block_stack
);
4098 BLOCK_SUBBLOCKS (block
) = blocks_nreverse_all (BLOCK_SUBBLOCKS (block
));
4100 VEC_free (tree
, heap
, block_stack
);
4103 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
4106 clear_block_marks (tree block
)
4110 TREE_ASM_WRITTEN (block
) = 0;
4111 clear_block_marks (BLOCK_SUBBLOCKS (block
));
4112 block
= BLOCK_CHAIN (block
);
4117 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
4121 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
4125 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
4127 tree block
= NOTE_BLOCK (insn
);
4130 gcc_assert (BLOCK_FRAGMENT_ORIGIN (block
) == NULL_TREE
);
4133 /* If we have seen this block before, that means it now
4134 spans multiple address regions. Create a new fragment. */
4135 if (TREE_ASM_WRITTEN (block
))
4137 tree new_block
= copy_node (block
);
4139 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
4140 BLOCK_FRAGMENT_CHAIN (new_block
)
4141 = BLOCK_FRAGMENT_CHAIN (origin
);
4142 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
4144 NOTE_BLOCK (insn
) = new_block
;
4148 BLOCK_SUBBLOCKS (block
) = 0;
4149 TREE_ASM_WRITTEN (block
) = 1;
4150 /* When there's only one block for the entire function,
4151 current_block == block and we mustn't do this, it
4152 will cause infinite recursion. */
4153 if (block
!= current_block
)
4155 if (block
!= origin
)
4156 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
4158 BLOCK_SUPERCONTEXT (block
) = current_block
;
4159 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
4160 BLOCK_SUBBLOCKS (current_block
) = block
;
4161 current_block
= origin
;
4163 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
4165 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
4167 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
4168 current_block
= BLOCK_SUPERCONTEXT (current_block
);
4174 /* Reverse the order of elements in the chain T of blocks,
4175 and return the new head of the chain (old last element). */
4178 blocks_nreverse (tree t
)
4180 tree prev
= 0, block
, next
;
4181 for (block
= t
; block
; block
= next
)
4183 next
= BLOCK_CHAIN (block
);
4184 BLOCK_CHAIN (block
) = prev
;
4190 /* Concatenate two chains of blocks (chained through BLOCK_CHAIN)
4191 by modifying the last node in chain 1 to point to chain 2. */
4194 block_chainon (tree op1
, tree op2
)
4203 for (t1
= op1
; BLOCK_CHAIN (t1
); t1
= BLOCK_CHAIN (t1
))
4205 BLOCK_CHAIN (t1
) = op2
;
4207 #ifdef ENABLE_TREE_CHECKING
4210 for (t2
= op2
; t2
; t2
= BLOCK_CHAIN (t2
))
4211 gcc_assert (t2
!= t1
);
4218 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4219 non-NULL, list them all into VECTOR, in a depth-first preorder
4220 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4224 all_blocks (tree block
, tree
*vector
)
4230 TREE_ASM_WRITTEN (block
) = 0;
4232 /* Record this block. */
4234 vector
[n_blocks
] = block
;
4238 /* Record the subblocks, and their subblocks... */
4239 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
4240 vector
? vector
+ n_blocks
: 0);
4241 block
= BLOCK_CHAIN (block
);
4247 /* Return a vector containing all the blocks rooted at BLOCK. The
4248 number of elements in the vector is stored in N_BLOCKS_P. The
4249 vector is dynamically allocated; it is the caller's responsibility
4250 to call `free' on the pointer returned. */
4253 get_block_vector (tree block
, int *n_blocks_p
)
4257 *n_blocks_p
= all_blocks (block
, NULL
);
4258 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
4259 all_blocks (block
, block_vector
);
4261 return block_vector
;
4264 static GTY(()) int next_block_index
= 2;
4266 /* Set BLOCK_NUMBER for all the blocks in FN. */
4269 number_blocks (tree fn
)
4275 /* For SDB and XCOFF debugging output, we start numbering the blocks
4276 from 1 within each function, rather than keeping a running
4278 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4279 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
4280 next_block_index
= 1;
4283 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
4285 /* The top-level BLOCK isn't numbered at all. */
4286 for (i
= 1; i
< n_blocks
; ++i
)
4287 /* We number the blocks from two. */
4288 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
4290 free (block_vector
);
4295 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4298 debug_find_var_in_block_tree (tree var
, tree block
)
4302 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4306 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4308 tree ret
= debug_find_var_in_block_tree (var
, t
);
4316 /* Keep track of whether we're in a dummy function context. If we are,
4317 we don't want to invoke the set_current_function hook, because we'll
4318 get into trouble if the hook calls target_reinit () recursively or
4319 when the initial initialization is not yet complete. */
4321 static bool in_dummy_function
;
4323 /* Invoke the target hook when setting cfun. Update the optimization options
4324 if the function uses different options than the default. */
4327 invoke_set_current_function_hook (tree fndecl
)
4329 if (!in_dummy_function
)
4331 tree opts
= ((fndecl
)
4332 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4333 : optimization_default_node
);
4336 opts
= optimization_default_node
;
4338 /* Change optimization options if needed. */
4339 if (optimization_current_node
!= opts
)
4341 optimization_current_node
= opts
;
4342 cl_optimization_restore (&global_options
, TREE_OPTIMIZATION (opts
));
4345 targetm
.set_current_function (fndecl
);
4349 /* cfun should never be set directly; use this function. */
4352 set_cfun (struct function
*new_cfun
)
4354 if (cfun
!= new_cfun
)
4357 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4361 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4363 static VEC(function_p
,heap
) *cfun_stack
;
4365 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4368 push_cfun (struct function
*new_cfun
)
4370 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4371 set_cfun (new_cfun
);
4374 /* Pop cfun from the stack. */
4379 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
4380 set_cfun (new_cfun
);
4383 /* Return value of funcdef and increase it. */
4385 get_next_funcdef_no (void)
4387 return funcdef_no
++;
4390 /* Return value of funcdef. */
4392 get_last_funcdef_no (void)
4397 /* Allocate a function structure for FNDECL and set its contents
4398 to the defaults. Set cfun to the newly-allocated object.
4399 Some of the helper functions invoked during initialization assume
4400 that cfun has already been set. Therefore, assign the new object
4401 directly into cfun and invoke the back end hook explicitly at the
4402 very end, rather than initializing a temporary and calling set_cfun
4405 ABSTRACT_P is true if this is a function that will never be seen by
4406 the middle-end. Such functions are front-end concepts (like C++
4407 function templates) that do not correspond directly to functions
4408 placed in object files. */
4411 allocate_struct_function (tree fndecl
, bool abstract_p
)
4414 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4416 cfun
= ggc_alloc_cleared_function ();
4418 init_eh_for_function ();
4420 if (init_machine_status
)
4421 cfun
->machine
= (*init_machine_status
) ();
4423 #ifdef OVERRIDE_ABI_FORMAT
4424 OVERRIDE_ABI_FORMAT (fndecl
);
4427 invoke_set_current_function_hook (fndecl
);
4429 if (fndecl
!= NULL_TREE
)
4431 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4432 cfun
->decl
= fndecl
;
4433 current_function_funcdef_no
= get_next_funcdef_no ();
4435 result
= DECL_RESULT (fndecl
);
4436 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4438 #ifdef PCC_STATIC_STRUCT_RETURN
4439 cfun
->returns_pcc_struct
= 1;
4441 cfun
->returns_struct
= 1;
4444 cfun
->stdarg
= stdarg_p (fntype
);
4446 /* Assume all registers in stdarg functions need to be saved. */
4447 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4448 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4450 /* ??? This could be set on a per-function basis by the front-end
4451 but is this worth the hassle? */
4452 cfun
->can_throw_non_call_exceptions
= flag_non_call_exceptions
;
4456 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4457 instead of just setting it. */
4460 push_struct_function (tree fndecl
)
4462 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4463 allocate_struct_function (fndecl
, false);
4466 /* Reset crtl and other non-struct-function variables to defaults as
4467 appropriate for emitting rtl at the start of a function. */
4470 prepare_function_start (void)
4472 gcc_assert (!crtl
->emit
.x_last_insn
);
4475 init_varasm_status ();
4477 default_rtl_profile ();
4479 if (flag_stack_usage
)
4481 cfun
->su
= ggc_alloc_cleared_stack_usage ();
4482 cfun
->su
->static_stack_size
= -1;
4485 cse_not_expected
= ! optimize
;
4487 /* Caller save not needed yet. */
4488 caller_save_needed
= 0;
4490 /* We haven't done register allocation yet. */
4493 /* Indicate that we have not instantiated virtual registers yet. */
4494 virtuals_instantiated
= 0;
4496 /* Indicate that we want CONCATs now. */
4497 generating_concat_p
= 1;
4499 /* Indicate we have no need of a frame pointer yet. */
4500 frame_pointer_needed
= 0;
4503 /* Initialize the rtl expansion mechanism so that we can do simple things
4504 like generate sequences. This is used to provide a context during global
4505 initialization of some passes. You must call expand_dummy_function_end
4506 to exit this context. */
4509 init_dummy_function_start (void)
4511 gcc_assert (!in_dummy_function
);
4512 in_dummy_function
= true;
4513 push_struct_function (NULL_TREE
);
4514 prepare_function_start ();
4517 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4518 and initialize static variables for generating RTL for the statements
4522 init_function_start (tree subr
)
4524 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4525 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4527 allocate_struct_function (subr
, false);
4528 prepare_function_start ();
4529 decide_function_section (subr
);
4531 /* Warn if this value is an aggregate type,
4532 regardless of which calling convention we are using for it. */
4533 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4534 warning (OPT_Waggregate_return
, "function returns an aggregate");
4537 /* Make sure all values used by the optimization passes have sane defaults. */
4539 init_function_for_compilation (void)
4545 struct rtl_opt_pass pass_init_function
=
4549 "*init_function", /* name */
4551 init_function_for_compilation
, /* execute */
4554 0, /* static_pass_number */
4555 TV_NONE
, /* tv_id */
4556 0, /* properties_required */
4557 0, /* properties_provided */
4558 0, /* properties_destroyed */
4559 0, /* todo_flags_start */
4560 0 /* todo_flags_finish */
4566 expand_main_function (void)
4568 #if (defined(INVOKE__main) \
4569 || (!defined(HAS_INIT_SECTION) \
4570 && !defined(INIT_SECTION_ASM_OP) \
4571 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4572 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4576 /* Expand code to initialize the stack_protect_guard. This is invoked at
4577 the beginning of a function to be protected. */
4579 #ifndef HAVE_stack_protect_set
4580 # define HAVE_stack_protect_set 0
4581 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4585 stack_protect_prologue (void)
4587 tree guard_decl
= targetm
.stack_protect_guard ();
4590 x
= expand_normal (crtl
->stack_protect_guard
);
4591 y
= expand_normal (guard_decl
);
4593 /* Allow the target to copy from Y to X without leaking Y into a
4595 if (HAVE_stack_protect_set
)
4597 rtx insn
= gen_stack_protect_set (x
, y
);
4605 /* Otherwise do a straight move. */
4606 emit_move_insn (x
, y
);
4609 /* Expand code to verify the stack_protect_guard. This is invoked at
4610 the end of a function to be protected. */
4612 #ifndef HAVE_stack_protect_test
4613 # define HAVE_stack_protect_test 0
4614 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4618 stack_protect_epilogue (void)
4620 tree guard_decl
= targetm
.stack_protect_guard ();
4621 rtx label
= gen_label_rtx ();
4624 x
= expand_normal (crtl
->stack_protect_guard
);
4625 y
= expand_normal (guard_decl
);
4627 /* Allow the target to compare Y with X without leaking either into
4629 switch (HAVE_stack_protect_test
!= 0)
4632 tmp
= gen_stack_protect_test (x
, y
, label
);
4641 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4645 /* The noreturn predictor has been moved to the tree level. The rtl-level
4646 predictors estimate this branch about 20%, which isn't enough to get
4647 things moved out of line. Since this is the only extant case of adding
4648 a noreturn function at the rtl level, it doesn't seem worth doing ought
4649 except adding the prediction by hand. */
4650 tmp
= get_last_insn ();
4652 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4654 expand_expr_stmt (targetm
.stack_protect_fail ());
4658 /* Start the RTL for a new function, and set variables used for
4660 SUBR is the FUNCTION_DECL node.
4661 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4662 the function's parameters, which must be run at any return statement. */
4665 expand_function_start (tree subr
)
4667 /* Make sure volatile mem refs aren't considered
4668 valid operands of arithmetic insns. */
4669 init_recog_no_volatile ();
4673 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4676 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4678 /* Make the label for return statements to jump to. Do not special
4679 case machines with special return instructions -- they will be
4680 handled later during jump, ifcvt, or epilogue creation. */
4681 return_label
= gen_label_rtx ();
4683 /* Initialize rtx used to return the value. */
4684 /* Do this before assign_parms so that we copy the struct value address
4685 before any library calls that assign parms might generate. */
4687 /* Decide whether to return the value in memory or in a register. */
4688 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4690 /* Returning something that won't go in a register. */
4691 rtx value_address
= 0;
4693 #ifdef PCC_STATIC_STRUCT_RETURN
4694 if (cfun
->returns_pcc_struct
)
4696 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4697 value_address
= assemble_static_space (size
);
4702 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4703 /* Expect to be passed the address of a place to store the value.
4704 If it is passed as an argument, assign_parms will take care of
4708 value_address
= gen_reg_rtx (Pmode
);
4709 emit_move_insn (value_address
, sv
);
4714 rtx x
= value_address
;
4715 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4717 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4718 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4720 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4723 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4724 /* If return mode is void, this decl rtl should not be used. */
4725 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4728 /* Compute the return values into a pseudo reg, which we will copy
4729 into the true return register after the cleanups are done. */
4730 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4731 if (TYPE_MODE (return_type
) != BLKmode
4732 && targetm
.calls
.return_in_msb (return_type
))
4733 /* expand_function_end will insert the appropriate padding in
4734 this case. Use the return value's natural (unpadded) mode
4735 within the function proper. */
4736 SET_DECL_RTL (DECL_RESULT (subr
),
4737 gen_reg_rtx (TYPE_MODE (return_type
)));
4740 /* In order to figure out what mode to use for the pseudo, we
4741 figure out what the mode of the eventual return register will
4742 actually be, and use that. */
4743 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4745 /* Structures that are returned in registers are not
4746 aggregate_value_p, so we may see a PARALLEL or a REG. */
4747 if (REG_P (hard_reg
))
4748 SET_DECL_RTL (DECL_RESULT (subr
),
4749 gen_reg_rtx (GET_MODE (hard_reg
)));
4752 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4753 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4757 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4758 result to the real return register(s). */
4759 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4762 /* Initialize rtx for parameters and local variables.
4763 In some cases this requires emitting insns. */
4764 assign_parms (subr
);
4766 /* If function gets a static chain arg, store it. */
4767 if (cfun
->static_chain_decl
)
4769 tree parm
= cfun
->static_chain_decl
;
4770 rtx local
, chain
, insn
;
4772 local
= gen_reg_rtx (Pmode
);
4773 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
4775 set_decl_incoming_rtl (parm
, chain
, false);
4776 SET_DECL_RTL (parm
, local
);
4777 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4779 insn
= emit_move_insn (local
, chain
);
4781 /* Mark the register as eliminable, similar to parameters. */
4783 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
4784 set_unique_reg_note (insn
, REG_EQUIV
, chain
);
4787 /* If the function receives a non-local goto, then store the
4788 bits we need to restore the frame pointer. */
4789 if (cfun
->nonlocal_goto_save_area
)
4794 /* ??? We need to do this save early. Unfortunately here is
4795 before the frame variable gets declared. Help out... */
4796 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4797 if (!DECL_RTL_SET_P (var
))
4800 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4801 cfun
->nonlocal_goto_save_area
,
4802 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4803 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4804 r_save
= convert_memory_address (Pmode
, r_save
);
4806 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4807 update_nonlocal_goto_save_area ();
4810 /* The following was moved from init_function_start.
4811 The move is supposed to make sdb output more accurate. */
4812 /* Indicate the beginning of the function body,
4813 as opposed to parm setup. */
4814 emit_note (NOTE_INSN_FUNCTION_BEG
);
4816 gcc_assert (NOTE_P (get_last_insn ()));
4818 parm_birth_insn
= get_last_insn ();
4823 PROFILE_HOOK (current_function_funcdef_no
);
4827 /* After the display initializations is where the stack checking
4829 if(flag_stack_check
)
4830 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4832 /* Make sure there is a line number after the function entry setup code. */
4833 force_next_line_note ();
4836 /* Undo the effects of init_dummy_function_start. */
4838 expand_dummy_function_end (void)
4840 gcc_assert (in_dummy_function
);
4842 /* End any sequences that failed to be closed due to syntax errors. */
4843 while (in_sequence_p ())
4846 /* Outside function body, can't compute type's actual size
4847 until next function's body starts. */
4849 free_after_parsing (cfun
);
4850 free_after_compilation (cfun
);
4852 in_dummy_function
= false;
4855 /* Call DOIT for each hard register used as a return value from
4856 the current function. */
4859 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4861 rtx outgoing
= crtl
->return_rtx
;
4866 if (REG_P (outgoing
))
4867 (*doit
) (outgoing
, arg
);
4868 else if (GET_CODE (outgoing
) == PARALLEL
)
4872 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4874 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4876 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4883 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4889 clobber_return_register (void)
4891 diddle_return_value (do_clobber_return_reg
, NULL
);
4893 /* In case we do use pseudo to return value, clobber it too. */
4894 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4896 tree decl_result
= DECL_RESULT (current_function_decl
);
4897 rtx decl_rtl
= DECL_RTL (decl_result
);
4898 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4900 do_clobber_return_reg (decl_rtl
, NULL
);
4906 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4912 use_return_register (void)
4914 diddle_return_value (do_use_return_reg
, NULL
);
4917 /* Possibly warn about unused parameters. */
4919 do_warn_unused_parameter (tree fn
)
4923 for (decl
= DECL_ARGUMENTS (fn
);
4924 decl
; decl
= DECL_CHAIN (decl
))
4925 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4926 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4927 && !TREE_NO_WARNING (decl
))
4928 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4931 static GTY(()) rtx initial_trampoline
;
4933 /* Generate RTL for the end of the current function. */
4936 expand_function_end (void)
4940 /* If arg_pointer_save_area was referenced only from a nested
4941 function, we will not have initialized it yet. Do that now. */
4942 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4943 get_arg_pointer_save_area ();
4945 /* If we are doing generic stack checking and this function makes calls,
4946 do a stack probe at the start of the function to ensure we have enough
4947 space for another stack frame. */
4948 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4952 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4955 rtx max_frame_size
= GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
);
4957 if (STACK_CHECK_MOVING_SP
)
4958 anti_adjust_stack_and_probe (max_frame_size
, true);
4960 probe_stack_range (STACK_OLD_CHECK_PROTECT
, max_frame_size
);
4963 set_insn_locators (seq
, prologue_locator
);
4964 emit_insn_before (seq
, stack_check_probe_note
);
4969 /* End any sequences that failed to be closed due to syntax errors. */
4970 while (in_sequence_p ())
4973 clear_pending_stack_adjust ();
4974 do_pending_stack_adjust ();
4976 /* Output a linenumber for the end of the function.
4977 SDB depends on this. */
4978 force_next_line_note ();
4979 set_curr_insn_source_location (input_location
);
4981 /* Before the return label (if any), clobber the return
4982 registers so that they are not propagated live to the rest of
4983 the function. This can only happen with functions that drop
4984 through; if there had been a return statement, there would
4985 have either been a return rtx, or a jump to the return label.
4987 We delay actual code generation after the current_function_value_rtx
4989 clobber_after
= get_last_insn ();
4991 /* Output the label for the actual return from the function. */
4992 emit_label (return_label
);
4994 if (targetm
.except_unwind_info (&global_options
) == UI_SJLJ
)
4996 /* Let except.c know where it should emit the call to unregister
4997 the function context for sjlj exceptions. */
4998 if (flag_exceptions
)
4999 sjlj_emit_function_exit_after (get_last_insn ());
5003 /* We want to ensure that instructions that may trap are not
5004 moved into the epilogue by scheduling, because we don't
5005 always emit unwind information for the epilogue. */
5006 if (cfun
->can_throw_non_call_exceptions
)
5007 emit_insn (gen_blockage ());
5010 /* If this is an implementation of throw, do what's necessary to
5011 communicate between __builtin_eh_return and the epilogue. */
5012 expand_eh_return ();
5014 /* If scalar return value was computed in a pseudo-reg, or was a named
5015 return value that got dumped to the stack, copy that to the hard
5017 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
5019 tree decl_result
= DECL_RESULT (current_function_decl
);
5020 rtx decl_rtl
= DECL_RTL (decl_result
);
5022 if (REG_P (decl_rtl
)
5023 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
5024 : DECL_REGISTER (decl_result
))
5026 rtx real_decl_rtl
= crtl
->return_rtx
;
5028 /* This should be set in assign_parms. */
5029 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
5031 /* If this is a BLKmode structure being returned in registers,
5032 then use the mode computed in expand_return. Note that if
5033 decl_rtl is memory, then its mode may have been changed,
5034 but that crtl->return_rtx has not. */
5035 if (GET_MODE (real_decl_rtl
) == BLKmode
)
5036 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
5038 /* If a non-BLKmode return value should be padded at the least
5039 significant end of the register, shift it left by the appropriate
5040 amount. BLKmode results are handled using the group load/store
5042 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
5043 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
5045 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
5046 REGNO (real_decl_rtl
)),
5048 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
5050 /* If a named return value dumped decl_return to memory, then
5051 we may need to re-do the PROMOTE_MODE signed/unsigned
5053 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
5055 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
5056 promote_function_mode (TREE_TYPE (decl_result
),
5057 GET_MODE (decl_rtl
), &unsignedp
,
5058 TREE_TYPE (current_function_decl
), 1);
5060 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
5062 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
5064 /* If expand_function_start has created a PARALLEL for decl_rtl,
5065 move the result to the real return registers. Otherwise, do
5066 a group load from decl_rtl for a named return. */
5067 if (GET_CODE (decl_rtl
) == PARALLEL
)
5068 emit_group_move (real_decl_rtl
, decl_rtl
);
5070 emit_group_load (real_decl_rtl
, decl_rtl
,
5071 TREE_TYPE (decl_result
),
5072 int_size_in_bytes (TREE_TYPE (decl_result
)));
5074 /* In the case of complex integer modes smaller than a word, we'll
5075 need to generate some non-trivial bitfield insertions. Do that
5076 on a pseudo and not the hard register. */
5077 else if (GET_CODE (decl_rtl
) == CONCAT
5078 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
5079 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
5081 int old_generating_concat_p
;
5084 old_generating_concat_p
= generating_concat_p
;
5085 generating_concat_p
= 0;
5086 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
5087 generating_concat_p
= old_generating_concat_p
;
5089 emit_move_insn (tmp
, decl_rtl
);
5090 emit_move_insn (real_decl_rtl
, tmp
);
5093 emit_move_insn (real_decl_rtl
, decl_rtl
);
5097 /* If returning a structure, arrange to return the address of the value
5098 in a place where debuggers expect to find it.
5100 If returning a structure PCC style,
5101 the caller also depends on this value.
5102 And cfun->returns_pcc_struct is not necessarily set. */
5103 if (cfun
->returns_struct
5104 || cfun
->returns_pcc_struct
)
5106 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
5107 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
5110 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
5111 type
= TREE_TYPE (type
);
5113 value_address
= XEXP (value_address
, 0);
5115 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
5116 current_function_decl
, true);
5118 /* Mark this as a function return value so integrate will delete the
5119 assignment and USE below when inlining this function. */
5120 REG_FUNCTION_VALUE_P (outgoing
) = 1;
5122 /* The address may be ptr_mode and OUTGOING may be Pmode. */
5123 value_address
= convert_memory_address (GET_MODE (outgoing
),
5126 emit_move_insn (outgoing
, value_address
);
5128 /* Show return register used to hold result (in this case the address
5130 crtl
->return_rtx
= outgoing
;
5133 /* Emit the actual code to clobber return register. */
5138 clobber_return_register ();
5142 emit_insn_after (seq
, clobber_after
);
5145 /* Output the label for the naked return from the function. */
5146 if (naked_return_label
)
5147 emit_label (naked_return_label
);
5149 /* @@@ This is a kludge. We want to ensure that instructions that
5150 may trap are not moved into the epilogue by scheduling, because
5151 we don't always emit unwind information for the epilogue. */
5152 if (cfun
->can_throw_non_call_exceptions
5153 && targetm
.except_unwind_info (&global_options
) != UI_SJLJ
)
5154 emit_insn (gen_blockage ());
5156 /* If stack protection is enabled for this function, check the guard. */
5157 if (crtl
->stack_protect_guard
)
5158 stack_protect_epilogue ();
5160 /* If we had calls to alloca, and this machine needs
5161 an accurate stack pointer to exit the function,
5162 insert some code to save and restore the stack pointer. */
5163 if (! EXIT_IGNORE_STACK
5164 && cfun
->calls_alloca
)
5169 emit_stack_save (SAVE_FUNCTION
, &tem
);
5172 emit_insn_before (seq
, parm_birth_insn
);
5174 emit_stack_restore (SAVE_FUNCTION
, tem
);
5177 /* ??? This should no longer be necessary since stupid is no longer with
5178 us, but there are some parts of the compiler (eg reload_combine, and
5179 sh mach_dep_reorg) that still try and compute their own lifetime info
5180 instead of using the general framework. */
5181 use_return_register ();
5185 get_arg_pointer_save_area (void)
5187 rtx ret
= arg_pointer_save_area
;
5191 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
5192 arg_pointer_save_area
= ret
;
5195 if (! crtl
->arg_pointer_save_area_init
)
5199 /* Save the arg pointer at the beginning of the function. The
5200 generated stack slot may not be a valid memory address, so we
5201 have to check it and fix it if necessary. */
5203 emit_move_insn (validize_mem (ret
),
5204 crtl
->args
.internal_arg_pointer
);
5208 push_topmost_sequence ();
5209 emit_insn_after (seq
, entry_of_function ());
5210 pop_topmost_sequence ();
5212 crtl
->arg_pointer_save_area_init
= true;
5218 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
5219 for the first time. */
5222 record_insns (rtx insns
, rtx end
, htab_t
*hashp
)
5225 htab_t hash
= *hashp
;
5229 = htab_create_ggc (17, htab_hash_pointer
, htab_eq_pointer
, NULL
);
5231 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
5233 void **slot
= htab_find_slot (hash
, tmp
, INSERT
);
5234 gcc_assert (*slot
== NULL
);
5239 /* INSN has been duplicated or replaced by as COPY, perhaps by duplicating a
5240 basic block, splitting or peepholes. If INSN is a prologue or epilogue
5241 insn, then record COPY as well. */
5244 maybe_copy_prologue_epilogue_insn (rtx insn
, rtx copy
)
5249 hash
= epilogue_insn_hash
;
5250 if (!hash
|| !htab_find (hash
, insn
))
5252 hash
= prologue_insn_hash
;
5253 if (!hash
|| !htab_find (hash
, insn
))
5257 slot
= htab_find_slot (hash
, copy
, INSERT
);
5258 gcc_assert (*slot
== NULL
);
5262 /* Set the locator of the insn chain starting at INSN to LOC. */
5264 set_insn_locators (rtx insn
, int loc
)
5266 while (insn
!= NULL_RTX
)
5269 INSN_LOCATOR (insn
) = loc
;
5270 insn
= NEXT_INSN (insn
);
5274 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5275 we can be running after reorg, SEQUENCE rtl is possible. */
5278 contains (const_rtx insn
, htab_t hash
)
5283 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5286 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
5287 if (htab_find (hash
, XVECEXP (PATTERN (insn
), 0, i
)))
5292 return htab_find (hash
, insn
) != NULL
;
5296 prologue_epilogue_contains (const_rtx insn
)
5298 if (contains (insn
, prologue_insn_hash
))
5300 if (contains (insn
, epilogue_insn_hash
))
5306 /* Insert use of return register before the end of BB. */
5309 emit_use_return_register_into_block (basic_block bb
)
5313 use_return_register ();
5316 emit_insn_before (seq
, BB_END (bb
));
5319 /* Insert gen_return at the end of block BB. This also means updating
5320 block_for_insn appropriately. */
5323 emit_return_into_block (basic_block bb
)
5325 emit_jump_insn_after (gen_return (), BB_END (bb
));
5327 #endif /* HAVE_return */
5329 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5330 this into place with notes indicating where the prologue ends and where
5331 the epilogue begins. Update the basic block information when possible. */
5334 thread_prologue_and_epilogue_insns (void)
5337 rtx seq ATTRIBUTE_UNUSED
, epilogue_end ATTRIBUTE_UNUSED
;
5341 rtl_profile_for_bb (ENTRY_BLOCK_PTR
);
5345 epilogue_end
= NULL_RTX
;
5347 /* Can't deal with multiple successors of the entry block at the
5348 moment. Function should always have at least one entry
5350 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5351 entry_edge
= single_succ_edge (ENTRY_BLOCK_PTR
);
5353 if (flag_split_stack
5354 && (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (cfun
->decl
))
5357 #ifndef HAVE_split_stack_prologue
5360 gcc_assert (HAVE_split_stack_prologue
);
5363 emit_insn (gen_split_stack_prologue ());
5367 record_insns (seq
, NULL
, &prologue_insn_hash
);
5368 set_insn_locators (seq
, prologue_locator
);
5370 insert_insn_on_edge (seq
, entry_edge
);
5375 #ifdef HAVE_prologue
5379 seq
= gen_prologue ();
5382 /* Insert an explicit USE for the frame pointer
5383 if the profiling is on and the frame pointer is required. */
5384 if (crtl
->profile
&& frame_pointer_needed
)
5385 emit_use (hard_frame_pointer_rtx
);
5387 /* Retain a map of the prologue insns. */
5388 record_insns (seq
, NULL
, &prologue_insn_hash
);
5389 emit_note (NOTE_INSN_PROLOGUE_END
);
5391 /* Ensure that instructions are not moved into the prologue when
5392 profiling is on. The call to the profiling routine can be
5393 emitted within the live range of a call-clobbered register. */
5394 if (!targetm
.profile_before_prologue () && crtl
->profile
)
5395 emit_insn (gen_blockage ());
5399 set_insn_locators (seq
, prologue_locator
);
5401 insert_insn_on_edge (seq
, entry_edge
);
5406 /* If the exit block has no non-fake predecessors, we don't need
5408 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5409 if ((e
->flags
& EDGE_FAKE
) == 0)
5414 rtl_profile_for_bb (EXIT_BLOCK_PTR
);
5416 if (optimize
&& HAVE_return
)
5418 /* If we're allowed to generate a simple return instruction,
5419 then by definition we don't need a full epilogue. Examine
5420 the block that falls through to EXIT. If it does not
5421 contain any code, examine its predecessors and try to
5422 emit (conditional) return instructions. */
5427 e
= find_fallthru_edge (EXIT_BLOCK_PTR
->preds
);
5432 /* Verify that there are no active instructions in the last block. */
5433 label
= BB_END (last
);
5434 while (label
&& !LABEL_P (label
))
5436 if (active_insn_p (label
))
5438 label
= PREV_INSN (label
);
5441 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5445 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5447 basic_block bb
= e
->src
;
5450 if (bb
== ENTRY_BLOCK_PTR
)
5457 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5463 /* If we have an unconditional jump, we can replace that
5464 with a simple return instruction. */
5465 if (simplejump_p (jump
))
5467 /* The use of the return register might be present in the exit
5468 fallthru block. Either:
5469 - removing the use is safe, and we should remove the use in
5470 the exit fallthru block, or
5471 - removing the use is not safe, and we should add it here.
5472 For now, we conservatively choose the latter. Either of the
5473 2 helps in crossjumping. */
5474 emit_use_return_register_into_block (bb
);
5476 emit_return_into_block (bb
);
5480 /* If we have a conditional jump, we can try to replace
5481 that with a conditional return instruction. */
5482 else if (condjump_p (jump
))
5484 if (! redirect_jump (jump
, 0, 0))
5490 /* See comment in simple_jump_p case above. */
5491 emit_use_return_register_into_block (bb
);
5493 /* If this block has only one successor, it both jumps
5494 and falls through to the fallthru block, so we can't
5496 if (single_succ_p (bb
))
5508 /* Fix up the CFG for the successful change we just made. */
5509 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5512 /* Emit a return insn for the exit fallthru block. Whether
5513 this is still reachable will be determined later. */
5515 emit_barrier_after (BB_END (last
));
5516 emit_return_into_block (last
);
5517 epilogue_end
= BB_END (last
);
5518 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5524 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5525 this marker for the splits of EH_RETURN patterns, and nothing else
5526 uses the flag in the meantime. */
5527 epilogue_completed
= 1;
5529 #ifdef HAVE_eh_return
5530 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5531 some targets, these get split to a special version of the epilogue
5532 code. In order to be able to properly annotate these with unwind
5533 info, try to split them now. If we get a valid split, drop an
5534 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5535 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5537 rtx prev
, last
, trial
;
5539 if (e
->flags
& EDGE_FALLTHRU
)
5541 last
= BB_END (e
->src
);
5542 if (!eh_returnjump_p (last
))
5545 prev
= PREV_INSN (last
);
5546 trial
= try_split (PATTERN (last
), last
, 1);
5550 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
5551 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
5555 /* Find the edge that falls through to EXIT. Other edges may exist
5556 due to RETURN instructions, but those don't need epilogues.
5557 There really shouldn't be a mixture -- either all should have
5558 been converted or none, however... */
5560 e
= find_fallthru_edge (EXIT_BLOCK_PTR
->preds
);
5564 #ifdef HAVE_epilogue
5568 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5569 seq
= gen_epilogue ();
5571 emit_jump_insn (seq
);
5573 /* Retain a map of the epilogue insns. */
5574 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5575 set_insn_locators (seq
, epilogue_locator
);
5580 insert_insn_on_edge (seq
, e
);
5588 if (! next_active_insn (BB_END (e
->src
)))
5590 /* We have a fall-through edge to the exit block, the source is not
5591 at the end of the function, and there will be an assembler epilogue
5592 at the end of the function.
5593 We can't use force_nonfallthru here, because that would try to
5594 use return. Inserting a jump 'by hand' is extremely messy, so
5595 we take advantage of cfg_layout_finalize using
5596 fixup_fallthru_exit_predecessor. */
5597 cfg_layout_initialize (0);
5598 FOR_EACH_BB (cur_bb
)
5599 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5600 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5601 cur_bb
->aux
= cur_bb
->next_bb
;
5602 cfg_layout_finalize ();
5606 default_rtl_profile ();
5612 commit_edge_insertions ();
5614 /* Look for basic blocks within the prologue insns. */
5615 blocks
= sbitmap_alloc (last_basic_block
);
5616 sbitmap_zero (blocks
);
5617 SET_BIT (blocks
, entry_edge
->dest
->index
);
5618 find_many_sub_basic_blocks (blocks
);
5619 sbitmap_free (blocks
);
5621 /* The epilogue insns we inserted may cause the exit edge to no longer
5623 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5625 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5626 && returnjump_p (BB_END (e
->src
)))
5627 e
->flags
&= ~EDGE_FALLTHRU
;
5631 #ifdef HAVE_sibcall_epilogue
5632 /* Emit sibling epilogues before any sibling call sites. */
5633 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5635 basic_block bb
= e
->src
;
5636 rtx insn
= BB_END (bb
);
5639 || ! SIBLING_CALL_P (insn
))
5646 emit_note (NOTE_INSN_EPILOGUE_BEG
);
5647 emit_insn (gen_sibcall_epilogue ());
5651 /* Retain a map of the epilogue insns. Used in life analysis to
5652 avoid getting rid of sibcall epilogue insns. Do this before we
5653 actually emit the sequence. */
5654 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5655 set_insn_locators (seq
, epilogue_locator
);
5657 emit_insn_before (seq
, insn
);
5662 #ifdef HAVE_epilogue
5667 /* Similarly, move any line notes that appear after the epilogue.
5668 There is no need, however, to be quite so anal about the existence
5669 of such a note. Also possibly move
5670 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5672 for (insn
= epilogue_end
; insn
; insn
= next
)
5674 next
= NEXT_INSN (insn
);
5676 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5677 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5682 /* Threading the prologue and epilogue changes the artificial refs
5683 in the entry and exit blocks. */
5684 epilogue_completed
= 1;
5685 df_update_entry_exit_and_calls ();
5688 /* Reposition the prologue-end and epilogue-begin notes after
5689 instruction scheduling. */
5692 reposition_prologue_and_epilogue_notes (void)
5694 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5695 || defined (HAVE_sibcall_epilogue)
5696 /* Since the hash table is created on demand, the fact that it is
5697 non-null is a signal that it is non-empty. */
5698 if (prologue_insn_hash
!= NULL
)
5700 size_t len
= htab_elements (prologue_insn_hash
);
5701 rtx insn
, last
= NULL
, note
= NULL
;
5703 /* Scan from the beginning until we reach the last prologue insn. */
5704 /* ??? While we do have the CFG intact, there are two problems:
5705 (1) The prologue can contain loops (typically probing the stack),
5706 which means that the end of the prologue isn't in the first bb.
5707 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5708 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5712 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5715 else if (contains (insn
, prologue_insn_hash
))
5727 /* Scan forward looking for the PROLOGUE_END note. It should
5728 be right at the beginning of the block, possibly with other
5729 insn notes that got moved there. */
5730 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
5733 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5738 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5740 last
= NEXT_INSN (last
);
5741 reorder_insns (note
, note
, last
);
5745 if (epilogue_insn_hash
!= NULL
)
5750 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5752 rtx insn
, first
= NULL
, note
= NULL
;
5753 basic_block bb
= e
->src
;
5755 /* Scan from the beginning until we reach the first epilogue insn. */
5756 FOR_BB_INSNS (bb
, insn
)
5760 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5767 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
5777 /* If the function has a single basic block, and no real
5778 epilogue insns (e.g. sibcall with no cleanup), the
5779 epilogue note can get scheduled before the prologue
5780 note. If we have frame related prologue insns, having
5781 them scanned during the epilogue will result in a crash.
5782 In this case re-order the epilogue note to just before
5783 the last insn in the block. */
5785 first
= BB_END (bb
);
5787 if (PREV_INSN (first
) != note
)
5788 reorder_insns (note
, note
, PREV_INSN (first
));
5792 #endif /* HAVE_prologue or HAVE_epilogue */
5795 /* Returns the name of the current function. */
5797 current_function_name (void)
5801 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5806 rest_of_handle_check_leaf_regs (void)
5808 #ifdef LEAF_REGISTERS
5809 current_function_uses_only_leaf_regs
5810 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5815 /* Insert a TYPE into the used types hash table of CFUN. */
5818 used_types_insert_helper (tree type
, struct function
*func
)
5820 if (type
!= NULL
&& func
!= NULL
)
5824 if (func
->used_types_hash
== NULL
)
5825 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5826 htab_eq_pointer
, NULL
);
5827 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5833 /* Given a type, insert it into the used hash table in cfun. */
5835 used_types_insert (tree t
)
5837 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5842 if (TREE_CODE (t
) == ERROR_MARK
)
5844 if (TYPE_NAME (t
) == NULL_TREE
5845 || TYPE_NAME (t
) == TYPE_NAME (TYPE_MAIN_VARIANT (t
)))
5846 t
= TYPE_MAIN_VARIANT (t
);
5847 if (debug_info_level
> DINFO_LEVEL_NONE
)
5850 used_types_insert_helper (t
, cfun
);
5852 /* So this might be a type referenced by a global variable.
5853 Record that type so that we can later decide to emit its debug
5855 VEC_safe_push (tree
, gc
, types_used_by_cur_var_decl
, t
);
5859 /* Helper to Hash a struct types_used_by_vars_entry. */
5862 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
5864 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
5866 return iterative_hash_object (entry
->type
,
5867 iterative_hash_object (entry
->var_decl
, 0));
5870 /* Hash function of the types_used_by_vars_entry hash table. */
5873 types_used_by_vars_do_hash (const void *x
)
5875 const struct types_used_by_vars_entry
*entry
=
5876 (const struct types_used_by_vars_entry
*) x
;
5878 return hash_types_used_by_vars_entry (entry
);
5881 /*Equality function of the types_used_by_vars_entry hash table. */
5884 types_used_by_vars_eq (const void *x1
, const void *x2
)
5886 const struct types_used_by_vars_entry
*e1
=
5887 (const struct types_used_by_vars_entry
*) x1
;
5888 const struct types_used_by_vars_entry
*e2
=
5889 (const struct types_used_by_vars_entry
*)x2
;
5891 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
5894 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5897 types_used_by_var_decl_insert (tree type
, tree var_decl
)
5899 if (type
!= NULL
&& var_decl
!= NULL
)
5902 struct types_used_by_vars_entry e
;
5903 e
.var_decl
= var_decl
;
5905 if (types_used_by_vars_hash
== NULL
)
5906 types_used_by_vars_hash
=
5907 htab_create_ggc (37, types_used_by_vars_do_hash
,
5908 types_used_by_vars_eq
, NULL
);
5909 slot
= htab_find_slot_with_hash (types_used_by_vars_hash
, &e
,
5910 hash_types_used_by_vars_entry (&e
), INSERT
);
5913 struct types_used_by_vars_entry
*entry
;
5914 entry
= ggc_alloc_types_used_by_vars_entry ();
5916 entry
->var_decl
= var_decl
;
5922 struct rtl_opt_pass pass_leaf_regs
=
5926 "*leaf_regs", /* name */
5928 rest_of_handle_check_leaf_regs
, /* execute */
5931 0, /* static_pass_number */
5932 TV_NONE
, /* tv_id */
5933 0, /* properties_required */
5934 0, /* properties_provided */
5935 0, /* properties_destroyed */
5936 0, /* todo_flags_start */
5937 0 /* todo_flags_finish */
5942 rest_of_handle_thread_prologue_and_epilogue (void)
5945 cleanup_cfg (CLEANUP_EXPENSIVE
);
5947 /* On some machines, the prologue and epilogue code, or parts thereof,
5948 can be represented as RTL. Doing so lets us schedule insns between
5949 it and the rest of the code and also allows delayed branch
5950 scheduling to operate in the epilogue. */
5951 thread_prologue_and_epilogue_insns ();
5953 /* The stack usage info is finalized during prologue expansion. */
5954 if (flag_stack_usage
)
5955 output_stack_usage ();
5960 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5964 "pro_and_epilogue", /* name */
5966 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5969 0, /* static_pass_number */
5970 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5971 0, /* properties_required */
5972 0, /* properties_provided */
5973 0, /* properties_destroyed */
5974 TODO_verify_flow
, /* todo_flags_start */
5977 TODO_df_finish
| TODO_verify_rtl_sharing
|
5978 TODO_ggc_collect
/* todo_flags_finish */
5983 /* This mini-pass fixes fall-out from SSA in asm statements that have
5984 in-out constraints. Say you start with
5987 asm ("": "+mr" (inout));
5990 which is transformed very early to use explicit output and match operands:
5993 asm ("": "=mr" (inout) : "0" (inout));
5996 Or, after SSA and copyprop,
5998 asm ("": "=mr" (inout_2) : "0" (inout_1));
6001 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
6002 they represent two separate values, so they will get different pseudo
6003 registers during expansion. Then, since the two operands need to match
6004 per the constraints, but use different pseudo registers, reload can
6005 only register a reload for these operands. But reloads can only be
6006 satisfied by hardregs, not by memory, so we need a register for this
6007 reload, just because we are presented with non-matching operands.
6008 So, even though we allow memory for this operand, no memory can be
6009 used for it, just because the two operands don't match. This can
6010 cause reload failures on register-starved targets.
6012 So it's a symptom of reload not being able to use memory for reloads
6013 or, alternatively it's also a symptom of both operands not coming into
6014 reload as matching (in which case the pseudo could go to memory just
6015 fine, as the alternative allows it, and no reload would be necessary).
6016 We fix the latter problem here, by transforming
6018 asm ("": "=mr" (inout_2) : "0" (inout_1));
6023 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
6026 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
6029 bool changed
= false;
6030 rtx op
= SET_SRC (p_sets
[0]);
6031 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
6032 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
6033 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
6035 memset (output_matched
, 0, noutputs
* sizeof (bool));
6036 for (i
= 0; i
< ninputs
; i
++)
6038 rtx input
, output
, insns
;
6039 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
6043 if (*constraint
== '%')
6046 match
= strtoul (constraint
, &end
, 10);
6047 if (end
== constraint
)
6050 gcc_assert (match
< noutputs
);
6051 output
= SET_DEST (p_sets
[match
]);
6052 input
= RTVEC_ELT (inputs
, i
);
6053 /* Only do the transformation for pseudos. */
6054 if (! REG_P (output
)
6055 || rtx_equal_p (output
, input
)
6056 || (GET_MODE (input
) != VOIDmode
6057 && GET_MODE (input
) != GET_MODE (output
)))
6060 /* We can't do anything if the output is also used as input,
6061 as we're going to overwrite it. */
6062 for (j
= 0; j
< ninputs
; j
++)
6063 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
6068 /* Avoid changing the same input several times. For
6069 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
6070 only change in once (to out1), rather than changing it
6071 first to out1 and afterwards to out2. */
6074 for (j
= 0; j
< noutputs
; j
++)
6075 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
6080 output_matched
[match
] = true;
6083 emit_move_insn (output
, input
);
6084 insns
= get_insns ();
6086 emit_insn_before (insns
, insn
);
6088 /* Now replace all mentions of the input with output. We can't
6089 just replace the occurrence in inputs[i], as the register might
6090 also be used in some other input (or even in an address of an
6091 output), which would mean possibly increasing the number of
6092 inputs by one (namely 'output' in addition), which might pose
6093 a too complicated problem for reload to solve. E.g. this situation:
6095 asm ("" : "=r" (output), "=m" (input) : "0" (input))
6097 Here 'input' is used in two occurrences as input (once for the
6098 input operand, once for the address in the second output operand).
6099 If we would replace only the occurrence of the input operand (to
6100 make the matching) we would be left with this:
6103 asm ("" : "=r" (output), "=m" (input) : "0" (output))
6105 Now we suddenly have two different input values (containing the same
6106 value, but different pseudos) where we formerly had only one.
6107 With more complicated asms this might lead to reload failures
6108 which wouldn't have happen without this pass. So, iterate over
6109 all operands and replace all occurrences of the register used. */
6110 for (j
= 0; j
< noutputs
; j
++)
6111 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
6112 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
6113 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
6115 for (j
= 0; j
< ninputs
; j
++)
6116 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
6117 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
6124 df_insn_rescan (insn
);
6128 rest_of_match_asm_constraints (void)
6131 rtx insn
, pat
, *p_sets
;
6134 if (!crtl
->has_asm_statement
)
6137 df_set_flags (DF_DEFER_INSN_RESCAN
);
6140 FOR_BB_INSNS (bb
, insn
)
6145 pat
= PATTERN (insn
);
6146 if (GET_CODE (pat
) == PARALLEL
)
6147 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
6148 else if (GET_CODE (pat
) == SET
)
6149 p_sets
= &PATTERN (insn
), noutputs
= 1;
6153 if (GET_CODE (*p_sets
) == SET
6154 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
6155 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
6159 return TODO_df_finish
;
6162 struct rtl_opt_pass pass_match_asm_constraints
=
6166 "asmcons", /* name */
6168 rest_of_match_asm_constraints
, /* execute */
6171 0, /* static_pass_number */
6172 TV_NONE
, /* tv_id */
6173 0, /* properties_required */
6174 0, /* properties_provided */
6175 0, /* properties_destroyed */
6176 0, /* todo_flags_start */
6177 TODO_dump_func
/* todo_flags_finish */
6182 #include "gt-function.h"