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 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf
;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging
;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs
;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated
;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no
;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function
* (*init_machine_status
) (void);
124 /* The currently compiled function. */
125 struct function
*cfun
= 0;
127 /* These hashes record the prologue and epilogue insns. */
128 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
129 htab_t prologue_insn_hash
;
130 static GTY((if_marked ("ggc_marked_p"), param_is (struct rtx_def
)))
131 htab_t epilogue_insn_hash
;
134 htab_t types_used_by_vars_hash
= NULL
;
135 tree types_used_by_cur_var_decl
= NULL
;
137 /* Forward declarations. */
139 static struct temp_slot
*find_temp_slot_from_address (rtx
);
140 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
141 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
142 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
143 static int all_blocks (tree
, tree
*);
144 static tree
*get_block_vector (tree
, int *);
145 extern tree
debug_find_var_in_block_tree (tree
, tree
);
146 /* We always define `record_insns' even if it's not used so that we
147 can always export `prologue_epilogue_contains'. */
148 static void record_insns (rtx
, rtx
, htab_t
*) ATTRIBUTE_UNUSED
;
149 static bool contains (const_rtx
, htab_t
);
151 static void emit_return_into_block (basic_block
);
153 static void prepare_function_start (void);
154 static void do_clobber_return_reg (rtx
, void *);
155 static void do_use_return_reg (rtx
, void *);
156 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
158 /* Stack of nested functions. */
159 /* Keep track of the cfun stack. */
161 typedef struct function
*function_p
;
163 DEF_VEC_P(function_p
);
164 DEF_VEC_ALLOC_P(function_p
,heap
);
165 static VEC(function_p
,heap
) *function_context_stack
;
167 /* Save the current context for compilation of a nested function.
168 This is called from language-specific code. */
171 push_function_context (void)
174 allocate_struct_function (NULL
, false);
176 VEC_safe_push (function_p
, heap
, function_context_stack
, cfun
);
180 /* Restore the last saved context, at the end of a nested function.
181 This function is called from language-specific code. */
184 pop_function_context (void)
186 struct function
*p
= VEC_pop (function_p
, function_context_stack
);
188 current_function_decl
= p
->decl
;
190 /* Reset variables that have known state during rtx generation. */
191 virtuals_instantiated
= 0;
192 generating_concat_p
= 1;
195 /* Clear out all parts of the state in F that can safely be discarded
196 after the function has been parsed, but not compiled, to let
197 garbage collection reclaim the memory. */
200 free_after_parsing (struct function
*f
)
205 /* Clear out all parts of the state in F that can safely be discarded
206 after the function has been compiled, to let garbage collection
207 reclaim the memory. */
210 free_after_compilation (struct function
*f
)
212 prologue_insn_hash
= NULL
;
213 epilogue_insn_hash
= NULL
;
215 if (crtl
->emit
.regno_pointer_align
)
216 free (crtl
->emit
.regno_pointer_align
);
218 memset (crtl
, 0, sizeof (struct rtl_data
));
223 regno_reg_rtx
= NULL
;
224 insn_locators_free ();
227 /* Return size needed for stack frame based on slots so far allocated.
228 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
229 the caller may have to do that. */
232 get_frame_size (void)
234 if (FRAME_GROWS_DOWNWARD
)
235 return -frame_offset
;
240 /* Issue an error message and return TRUE if frame OFFSET overflows in
241 the signed target pointer arithmetics for function FUNC. Otherwise
245 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
247 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
249 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
250 /* Leave room for the fixed part of the frame. */
251 - 64 * UNITS_PER_WORD
)
253 error_at (DECL_SOURCE_LOCATION (func
),
254 "total size of local objects too large");
261 /* Return stack slot alignment in bits for TYPE and MODE. */
264 get_stack_local_alignment (tree type
, enum machine_mode mode
)
266 unsigned int alignment
;
269 alignment
= BIGGEST_ALIGNMENT
;
271 alignment
= GET_MODE_ALIGNMENT (mode
);
273 /* Allow the frond-end to (possibly) increase the alignment of this
276 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
278 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
281 /* Determine whether it is possible to fit a stack slot of size SIZE and
282 alignment ALIGNMENT into an area in the stack frame that starts at
283 frame offset START and has a length of LENGTH. If so, store the frame
284 offset to be used for the stack slot in *POFFSET and return true;
285 return false otherwise. This function will extend the frame size when
286 given a start/length pair that lies at the end of the frame. */
289 try_fit_stack_local (HOST_WIDE_INT start
, HOST_WIDE_INT length
,
290 HOST_WIDE_INT size
, unsigned int alignment
,
291 HOST_WIDE_INT
*poffset
)
293 HOST_WIDE_INT this_frame_offset
;
294 int frame_off
, frame_alignment
, frame_phase
;
296 /* Calculate how many bytes the start of local variables is off from
298 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
299 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
300 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
302 /* Round the frame offset to the specified alignment. */
304 /* We must be careful here, since FRAME_OFFSET might be negative and
305 division with a negative dividend isn't as well defined as we might
306 like. So we instead assume that ALIGNMENT is a power of two and
307 use logical operations which are unambiguous. */
308 if (FRAME_GROWS_DOWNWARD
)
310 = (FLOOR_ROUND (start
+ length
- size
- frame_phase
,
311 (unsigned HOST_WIDE_INT
) alignment
)
315 = (CEIL_ROUND (start
- frame_phase
,
316 (unsigned HOST_WIDE_INT
) alignment
)
319 /* See if it fits. If this space is at the edge of the frame,
320 consider extending the frame to make it fit. Our caller relies on
321 this when allocating a new slot. */
322 if (frame_offset
== start
&& this_frame_offset
< frame_offset
)
323 frame_offset
= this_frame_offset
;
324 else if (this_frame_offset
< start
)
326 else if (start
+ length
== frame_offset
327 && this_frame_offset
+ size
> start
+ length
)
328 frame_offset
= this_frame_offset
+ size
;
329 else if (this_frame_offset
+ size
> start
+ length
)
332 *poffset
= this_frame_offset
;
336 /* Create a new frame_space structure describing free space in the stack
337 frame beginning at START and ending at END, and chain it into the
338 function's frame_space_list. */
341 add_frame_space (HOST_WIDE_INT start
, HOST_WIDE_INT end
)
343 struct frame_space
*space
= ggc_alloc_frame_space ();
344 space
->next
= crtl
->frame_space_list
;
345 crtl
->frame_space_list
= space
;
346 space
->start
= start
;
347 space
->length
= end
- start
;
350 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
351 with machine mode MODE.
353 ALIGN controls the amount of alignment for the address of the slot:
354 0 means according to MODE,
355 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
356 -2 means use BITS_PER_UNIT,
357 positive specifies alignment boundary in bits.
359 If REDUCE_ALIGNMENT_OK is true, it is OK to reduce alignment.
361 We do not round to stack_boundary here. */
364 assign_stack_local_1 (enum machine_mode mode
, HOST_WIDE_INT size
,
366 bool reduce_alignment_ok ATTRIBUTE_UNUSED
)
369 int bigend_correction
= 0;
370 HOST_WIDE_INT slot_offset
= 0, old_frame_offset
;
371 unsigned int alignment
, alignment_in_bits
;
375 alignment
= get_stack_local_alignment (NULL
, mode
);
376 alignment
/= BITS_PER_UNIT
;
378 else if (align
== -1)
380 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
381 size
= CEIL_ROUND (size
, alignment
);
383 else if (align
== -2)
384 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
386 alignment
= align
/ BITS_PER_UNIT
;
388 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
390 /* Ignore alignment if it exceeds MAX_SUPPORTED_STACK_ALIGNMENT. */
391 if (alignment_in_bits
> MAX_SUPPORTED_STACK_ALIGNMENT
)
393 alignment_in_bits
= MAX_SUPPORTED_STACK_ALIGNMENT
;
394 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
397 if (SUPPORTS_STACK_ALIGNMENT
)
399 if (crtl
->stack_alignment_estimated
< alignment_in_bits
)
401 if (!crtl
->stack_realign_processed
)
402 crtl
->stack_alignment_estimated
= alignment_in_bits
;
405 /* If stack is realigned and stack alignment value
406 hasn't been finalized, it is OK not to increase
407 stack_alignment_estimated. The bigger alignment
408 requirement is recorded in stack_alignment_needed
410 gcc_assert (!crtl
->stack_realign_finalized
);
411 if (!crtl
->stack_realign_needed
)
413 /* It is OK to reduce the alignment as long as the
414 requested size is 0 or the estimated stack
415 alignment >= mode alignment. */
416 gcc_assert (reduce_alignment_ok
418 || (crtl
->stack_alignment_estimated
419 >= GET_MODE_ALIGNMENT (mode
)));
420 alignment_in_bits
= crtl
->stack_alignment_estimated
;
421 alignment
= alignment_in_bits
/ BITS_PER_UNIT
;
427 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
428 crtl
->stack_alignment_needed
= alignment_in_bits
;
429 if (crtl
->max_used_stack_slot_alignment
< alignment_in_bits
)
430 crtl
->max_used_stack_slot_alignment
= alignment_in_bits
;
432 if (mode
!= BLKmode
|| size
!= 0)
434 struct frame_space
**psp
;
436 for (psp
= &crtl
->frame_space_list
; *psp
; psp
= &(*psp
)->next
)
438 struct frame_space
*space
= *psp
;
439 if (!try_fit_stack_local (space
->start
, space
->length
, size
,
440 alignment
, &slot_offset
))
443 if (slot_offset
> space
->start
)
444 add_frame_space (space
->start
, slot_offset
);
445 if (slot_offset
+ size
< space
->start
+ space
->length
)
446 add_frame_space (slot_offset
+ size
,
447 space
->start
+ space
->length
);
451 else if (!STACK_ALIGNMENT_NEEDED
)
453 slot_offset
= frame_offset
;
457 old_frame_offset
= frame_offset
;
459 if (FRAME_GROWS_DOWNWARD
)
461 frame_offset
-= size
;
462 try_fit_stack_local (frame_offset
, size
, size
, alignment
, &slot_offset
);
464 if (slot_offset
> frame_offset
)
465 add_frame_space (frame_offset
, slot_offset
);
466 if (slot_offset
+ size
< old_frame_offset
)
467 add_frame_space (slot_offset
+ size
, old_frame_offset
);
471 frame_offset
+= size
;
472 try_fit_stack_local (old_frame_offset
, size
, size
, alignment
, &slot_offset
);
474 if (slot_offset
> old_frame_offset
)
475 add_frame_space (old_frame_offset
, slot_offset
);
476 if (slot_offset
+ size
< frame_offset
)
477 add_frame_space (slot_offset
+ size
, frame_offset
);
481 /* On a big-endian machine, if we are allocating more space than we will use,
482 use the least significant bytes of those that are allocated. */
483 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
484 bigend_correction
= size
- GET_MODE_SIZE (mode
);
486 /* If we have already instantiated virtual registers, return the actual
487 address relative to the frame pointer. */
488 if (virtuals_instantiated
)
489 addr
= plus_constant (frame_pointer_rtx
,
491 (slot_offset
+ bigend_correction
492 + STARTING_FRAME_OFFSET
, Pmode
));
494 addr
= plus_constant (virtual_stack_vars_rtx
,
496 (slot_offset
+ bigend_correction
,
499 x
= gen_rtx_MEM (mode
, addr
);
500 set_mem_align (x
, alignment_in_bits
);
501 MEM_NOTRAP_P (x
) = 1;
504 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
506 if (frame_offset_overflow (frame_offset
, current_function_decl
))
512 /* Wrap up assign_stack_local_1 with last parameter as false. */
515 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
517 return assign_stack_local_1 (mode
, size
, align
, false);
521 /* In order to evaluate some expressions, such as function calls returning
522 structures in memory, we need to temporarily allocate stack locations.
523 We record each allocated temporary in the following structure.
525 Associated with each temporary slot is a nesting level. When we pop up
526 one level, all temporaries associated with the previous level are freed.
527 Normally, all temporaries are freed after the execution of the statement
528 in which they were created. However, if we are inside a ({...}) grouping,
529 the result may be in a temporary and hence must be preserved. If the
530 result could be in a temporary, we preserve it if we can determine which
531 one it is in. If we cannot determine which temporary may contain the
532 result, all temporaries are preserved. A temporary is preserved by
533 pretending it was allocated at the previous nesting level.
535 Automatic variables are also assigned temporary slots, at the nesting
536 level where they are defined. They are marked a "kept" so that
537 free_temp_slots will not free them. */
539 struct GTY(()) temp_slot
{
540 /* Points to next temporary slot. */
541 struct temp_slot
*next
;
542 /* Points to previous temporary slot. */
543 struct temp_slot
*prev
;
544 /* The rtx to used to reference the slot. */
546 /* The size, in units, of the slot. */
548 /* The type of the object in the slot, or zero if it doesn't correspond
549 to a type. We use this to determine whether a slot can be reused.
550 It can be reused if objects of the type of the new slot will always
551 conflict with objects of the type of the old slot. */
553 /* The alignment (in bits) of the slot. */
555 /* Nonzero if this temporary is currently in use. */
557 /* Nonzero if this temporary has its address taken. */
559 /* Nesting level at which this slot is being used. */
561 /* Nonzero if this should survive a call to free_temp_slots. */
563 /* The offset of the slot from the frame_pointer, including extra space
564 for alignment. This info is for combine_temp_slots. */
565 HOST_WIDE_INT base_offset
;
566 /* The size of the slot, including extra space for alignment. This
567 info is for combine_temp_slots. */
568 HOST_WIDE_INT full_size
;
571 /* A table of addresses that represent a stack slot. The table is a mapping
572 from address RTXen to a temp slot. */
573 static GTY((param_is(struct temp_slot_address_entry
))) htab_t temp_slot_address_table
;
575 /* Entry for the above hash table. */
576 struct GTY(()) temp_slot_address_entry
{
579 struct temp_slot
*temp_slot
;
582 /* Removes temporary slot TEMP from LIST. */
585 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
588 temp
->next
->prev
= temp
->prev
;
590 temp
->prev
->next
= temp
->next
;
594 temp
->prev
= temp
->next
= NULL
;
597 /* Inserts temporary slot TEMP to LIST. */
600 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
604 (*list
)->prev
= temp
;
609 /* Returns the list of used temp slots at LEVEL. */
611 static struct temp_slot
**
612 temp_slots_at_level (int level
)
614 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
615 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
617 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
620 /* Returns the maximal temporary slot level. */
623 max_slot_level (void)
625 if (!used_temp_slots
)
628 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
631 /* Moves temporary slot TEMP to LEVEL. */
634 move_slot_to_level (struct temp_slot
*temp
, int level
)
636 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
637 insert_slot_to_list (temp
, temp_slots_at_level (level
));
641 /* Make temporary slot TEMP available. */
644 make_slot_available (struct temp_slot
*temp
)
646 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
647 insert_slot_to_list (temp
, &avail_temp_slots
);
652 /* Compute the hash value for an address -> temp slot mapping.
653 The value is cached on the mapping entry. */
655 temp_slot_address_compute_hash (struct temp_slot_address_entry
*t
)
657 int do_not_record
= 0;
658 return hash_rtx (t
->address
, GET_MODE (t
->address
),
659 &do_not_record
, NULL
, false);
662 /* Return the hash value for an address -> temp slot mapping. */
664 temp_slot_address_hash (const void *p
)
666 const struct temp_slot_address_entry
*t
;
667 t
= (const struct temp_slot_address_entry
*) p
;
671 /* Compare two address -> temp slot mapping entries. */
673 temp_slot_address_eq (const void *p1
, const void *p2
)
675 const struct temp_slot_address_entry
*t1
, *t2
;
676 t1
= (const struct temp_slot_address_entry
*) p1
;
677 t2
= (const struct temp_slot_address_entry
*) p2
;
678 return exp_equiv_p (t1
->address
, t2
->address
, 0, true);
681 /* Add ADDRESS as an alias of TEMP_SLOT to the addess -> temp slot mapping. */
683 insert_temp_slot_address (rtx address
, struct temp_slot
*temp_slot
)
686 struct temp_slot_address_entry
*t
= ggc_alloc_temp_slot_address_entry ();
687 t
->address
= address
;
688 t
->temp_slot
= temp_slot
;
689 t
->hash
= temp_slot_address_compute_hash (t
);
690 slot
= htab_find_slot_with_hash (temp_slot_address_table
, t
, t
->hash
, INSERT
);
694 /* Remove an address -> temp slot mapping entry if the temp slot is
695 not in use anymore. Callback for remove_unused_temp_slot_addresses. */
697 remove_unused_temp_slot_addresses_1 (void **slot
, void *data ATTRIBUTE_UNUSED
)
699 const struct temp_slot_address_entry
*t
;
700 t
= (const struct temp_slot_address_entry
*) *slot
;
701 if (! t
->temp_slot
->in_use
)
706 /* Remove all mappings of addresses to unused temp slots. */
708 remove_unused_temp_slot_addresses (void)
710 htab_traverse (temp_slot_address_table
,
711 remove_unused_temp_slot_addresses_1
,
715 /* Find the temp slot corresponding to the object at address X. */
717 static struct temp_slot
*
718 find_temp_slot_from_address (rtx x
)
721 struct temp_slot_address_entry tmp
, *t
;
723 /* First try the easy way:
724 See if X exists in the address -> temp slot mapping. */
726 tmp
.temp_slot
= NULL
;
727 tmp
.hash
= temp_slot_address_compute_hash (&tmp
);
728 t
= (struct temp_slot_address_entry
*)
729 htab_find_with_hash (temp_slot_address_table
, &tmp
, tmp
.hash
);
733 /* If we have a sum involving a register, see if it points to a temp
735 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
736 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
738 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
739 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
742 /* Last resort: Address is a virtual stack var address. */
743 if (GET_CODE (x
) == PLUS
744 && XEXP (x
, 0) == virtual_stack_vars_rtx
745 && CONST_INT_P (XEXP (x
, 1)))
748 for (i
= max_slot_level (); i
>= 0; i
--)
749 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
751 if (INTVAL (XEXP (x
, 1)) >= p
->base_offset
752 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
)
760 /* Allocate a temporary stack slot and record it for possible later
763 MODE is the machine mode to be given to the returned rtx.
765 SIZE is the size in units of the space required. We do no rounding here
766 since assign_stack_local will do any required rounding.
768 KEEP is 1 if this slot is to be retained after a call to
769 free_temp_slots. Automatic variables for a block are allocated
770 with this flag. KEEP values of 2 or 3 were needed respectively
771 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
772 or for SAVE_EXPRs, but they are now unused.
774 TYPE is the type that will be used for the stack slot. */
777 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
781 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
784 /* If SIZE is -1 it means that somebody tried to allocate a temporary
785 of a variable size. */
786 gcc_assert (size
!= -1);
788 /* These are now unused. */
789 gcc_assert (keep
<= 1);
791 align
= get_stack_local_alignment (type
, mode
);
793 /* Try to find an available, already-allocated temporary of the proper
794 mode which meets the size and alignment requirements. Choose the
795 smallest one with the closest alignment.
797 If assign_stack_temp is called outside of the tree->rtl expansion,
798 we cannot reuse the stack slots (that may still refer to
799 VIRTUAL_STACK_VARS_REGNUM). */
800 if (!virtuals_instantiated
)
802 for (p
= avail_temp_slots
; p
; p
= p
->next
)
804 if (p
->align
>= align
&& p
->size
>= size
805 && GET_MODE (p
->slot
) == mode
806 && objects_must_conflict_p (p
->type
, type
)
807 && (best_p
== 0 || best_p
->size
> p
->size
808 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
810 if (p
->align
== align
&& p
->size
== size
)
813 cut_slot_from_list (selected
, &avail_temp_slots
);
822 /* Make our best, if any, the one to use. */
826 cut_slot_from_list (selected
, &avail_temp_slots
);
828 /* If there are enough aligned bytes left over, make them into a new
829 temp_slot so that the extra bytes don't get wasted. Do this only
830 for BLKmode slots, so that we can be sure of the alignment. */
831 if (GET_MODE (best_p
->slot
) == BLKmode
)
833 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
834 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
836 if (best_p
->size
- rounded_size
>= alignment
)
838 p
= ggc_alloc_temp_slot ();
839 p
->in_use
= p
->addr_taken
= 0;
840 p
->size
= best_p
->size
- rounded_size
;
841 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
842 p
->full_size
= best_p
->full_size
- rounded_size
;
843 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
844 p
->align
= best_p
->align
;
845 p
->type
= best_p
->type
;
846 insert_slot_to_list (p
, &avail_temp_slots
);
848 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
851 best_p
->size
= rounded_size
;
852 best_p
->full_size
= rounded_size
;
857 /* If we still didn't find one, make a new temporary. */
860 HOST_WIDE_INT frame_offset_old
= frame_offset
;
862 p
= ggc_alloc_temp_slot ();
864 /* We are passing an explicit alignment request to assign_stack_local.
865 One side effect of that is assign_stack_local will not round SIZE
866 to ensure the frame offset remains suitably aligned.
868 So for requests which depended on the rounding of SIZE, we go ahead
869 and round it now. We also make sure ALIGNMENT is at least
870 BIGGEST_ALIGNMENT. */
871 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
872 p
->slot
= assign_stack_local (mode
,
874 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
880 /* The following slot size computation is necessary because we don't
881 know the actual size of the temporary slot until assign_stack_local
882 has performed all the frame alignment and size rounding for the
883 requested temporary. Note that extra space added for alignment
884 can be either above or below this stack slot depending on which
885 way the frame grows. We include the extra space if and only if it
886 is above this slot. */
887 if (FRAME_GROWS_DOWNWARD
)
888 p
->size
= frame_offset_old
- frame_offset
;
892 /* Now define the fields used by combine_temp_slots. */
893 if (FRAME_GROWS_DOWNWARD
)
895 p
->base_offset
= frame_offset
;
896 p
->full_size
= frame_offset_old
- frame_offset
;
900 p
->base_offset
= frame_offset_old
;
901 p
->full_size
= frame_offset
- frame_offset_old
;
911 p
->level
= temp_slot_level
;
914 pp
= temp_slots_at_level (p
->level
);
915 insert_slot_to_list (p
, pp
);
916 insert_temp_slot_address (XEXP (p
->slot
, 0), p
);
918 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
919 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
920 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
922 /* If we know the alias set for the memory that will be used, use
923 it. If there's no TYPE, then we don't know anything about the
924 alias set for the memory. */
925 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
926 set_mem_align (slot
, align
);
928 /* If a type is specified, set the relevant flags. */
931 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
932 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
933 || TREE_CODE (type
) == COMPLEX_TYPE
));
935 MEM_NOTRAP_P (slot
) = 1;
940 /* Allocate a temporary stack slot and record it for possible later
941 reuse. First three arguments are same as in preceding function. */
944 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
946 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
949 /* Assign a temporary.
950 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
951 and so that should be used in error messages. In either case, we
952 allocate of the given type.
953 KEEP is as for assign_stack_temp.
954 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
955 it is 0 if a register is OK.
956 DONT_PROMOTE is 1 if we should not promote values in register
960 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
961 int dont_promote ATTRIBUTE_UNUSED
)
964 enum machine_mode mode
;
969 if (DECL_P (type_or_decl
))
970 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
972 decl
= NULL
, type
= type_or_decl
;
974 mode
= TYPE_MODE (type
);
976 unsignedp
= TYPE_UNSIGNED (type
);
979 if (mode
== BLKmode
|| memory_required
)
981 HOST_WIDE_INT size
= int_size_in_bytes (type
);
984 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
985 problems with allocating the stack space. */
989 /* Unfortunately, we don't yet know how to allocate variable-sized
990 temporaries. However, sometimes we can find a fixed upper limit on
991 the size, so try that instead. */
993 size
= max_int_size_in_bytes (type
);
995 /* The size of the temporary may be too large to fit into an integer. */
996 /* ??? Not sure this should happen except for user silliness, so limit
997 this to things that aren't compiler-generated temporaries. The
998 rest of the time we'll die in assign_stack_temp_for_type. */
999 if (decl
&& size
== -1
1000 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
1002 error ("size of variable %q+D is too large", decl
);
1006 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
1012 mode
= promote_mode (type
, mode
, &unsignedp
);
1015 return gen_reg_rtx (mode
);
1018 /* Combine temporary stack slots which are adjacent on the stack.
1020 This allows for better use of already allocated stack space. This is only
1021 done for BLKmode slots because we can be sure that we won't have alignment
1022 problems in this case. */
1025 combine_temp_slots (void)
1027 struct temp_slot
*p
, *q
, *next
, *next_q
;
1030 /* We can't combine slots, because the information about which slot
1031 is in which alias set will be lost. */
1032 if (flag_strict_aliasing
)
1035 /* If there are a lot of temp slots, don't do anything unless
1036 high levels of optimization. */
1037 if (! flag_expensive_optimizations
)
1038 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
1039 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
1042 for (p
= avail_temp_slots
; p
; p
= next
)
1048 if (GET_MODE (p
->slot
) != BLKmode
)
1051 for (q
= p
->next
; q
; q
= next_q
)
1057 if (GET_MODE (q
->slot
) != BLKmode
)
1060 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
1062 /* Q comes after P; combine Q into P. */
1064 p
->full_size
+= q
->full_size
;
1067 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
1069 /* P comes after Q; combine P into Q. */
1071 q
->full_size
+= p
->full_size
;
1076 cut_slot_from_list (q
, &avail_temp_slots
);
1079 /* Either delete P or advance past it. */
1081 cut_slot_from_list (p
, &avail_temp_slots
);
1085 /* Indicate that NEW_RTX is an alternate way of referring to the temp
1086 slot that previously was known by OLD_RTX. */
1089 update_temp_slot_address (rtx old_rtx
, rtx new_rtx
)
1091 struct temp_slot
*p
;
1093 if (rtx_equal_p (old_rtx
, new_rtx
))
1096 p
= find_temp_slot_from_address (old_rtx
);
1098 /* If we didn't find one, see if both OLD_RTX is a PLUS. If so, and
1099 NEW_RTX is a register, see if one operand of the PLUS is a
1100 temporary location. If so, NEW_RTX points into it. Otherwise,
1101 if both OLD_RTX and NEW_RTX are a PLUS and if there is a register
1102 in common between them. If so, try a recursive call on those
1106 if (GET_CODE (old_rtx
) != PLUS
)
1109 if (REG_P (new_rtx
))
1111 update_temp_slot_address (XEXP (old_rtx
, 0), new_rtx
);
1112 update_temp_slot_address (XEXP (old_rtx
, 1), new_rtx
);
1115 else if (GET_CODE (new_rtx
) != PLUS
)
1118 if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0)))
1119 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1));
1120 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0)))
1121 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1));
1122 else if (rtx_equal_p (XEXP (old_rtx
, 0), XEXP (new_rtx
, 1)))
1123 update_temp_slot_address (XEXP (old_rtx
, 1), XEXP (new_rtx
, 0));
1124 else if (rtx_equal_p (XEXP (old_rtx
, 1), XEXP (new_rtx
, 1)))
1125 update_temp_slot_address (XEXP (old_rtx
, 0), XEXP (new_rtx
, 0));
1130 /* Otherwise add an alias for the temp's address. */
1131 insert_temp_slot_address (new_rtx
, p
);
1134 /* If X could be a reference to a temporary slot, mark the fact that its
1135 address was taken. */
1138 mark_temp_addr_taken (rtx x
)
1140 struct temp_slot
*p
;
1145 /* If X is not in memory or is at a constant address, it cannot be in
1146 a temporary slot. */
1147 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
1150 p
= find_temp_slot_from_address (XEXP (x
, 0));
1155 /* If X could be a reference to a temporary slot, mark that slot as
1156 belonging to the to one level higher than the current level. If X
1157 matched one of our slots, just mark that one. Otherwise, we can't
1158 easily predict which it is, so upgrade all of them. Kept slots
1159 need not be touched.
1161 This is called when an ({...}) construct occurs and a statement
1162 returns a value in memory. */
1165 preserve_temp_slots (rtx x
)
1167 struct temp_slot
*p
= 0, *next
;
1169 /* If there is no result, we still might have some objects whose address
1170 were taken, so we need to make sure they stay around. */
1173 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1178 move_slot_to_level (p
, temp_slot_level
- 1);
1184 /* If X is a register that is being used as a pointer, see if we have
1185 a temporary slot we know it points to. To be consistent with
1186 the code below, we really should preserve all non-kept slots
1187 if we can't find a match, but that seems to be much too costly. */
1188 if (REG_P (x
) && REG_POINTER (x
))
1189 p
= find_temp_slot_from_address (x
);
1191 /* If X is not in memory or is at a constant address, it cannot be in
1192 a temporary slot, but it can contain something whose address was
1194 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1196 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1201 move_slot_to_level (p
, temp_slot_level
- 1);
1207 /* First see if we can find a match. */
1209 p
= find_temp_slot_from_address (XEXP (x
, 0));
1213 /* Move everything at our level whose address was taken to our new
1214 level in case we used its address. */
1215 struct temp_slot
*q
;
1217 if (p
->level
== temp_slot_level
)
1219 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1223 if (p
!= q
&& q
->addr_taken
)
1224 move_slot_to_level (q
, temp_slot_level
- 1);
1227 move_slot_to_level (p
, temp_slot_level
- 1);
1233 /* Otherwise, preserve all non-kept slots at this level. */
1234 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1239 move_slot_to_level (p
, temp_slot_level
- 1);
1243 /* Free all temporaries used so far. This is normally called at the
1244 end of generating code for a statement. */
1247 free_temp_slots (void)
1249 struct temp_slot
*p
, *next
;
1250 bool some_available
= false;
1252 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1258 make_slot_available (p
);
1259 some_available
= true;
1265 remove_unused_temp_slot_addresses ();
1266 combine_temp_slots ();
1270 /* Push deeper into the nesting level for stack temporaries. */
1273 push_temp_slots (void)
1278 /* Pop a temporary nesting level. All slots in use in the current level
1282 pop_temp_slots (void)
1284 struct temp_slot
*p
, *next
;
1285 bool some_available
= false;
1287 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1290 make_slot_available (p
);
1291 some_available
= true;
1296 remove_unused_temp_slot_addresses ();
1297 combine_temp_slots ();
1303 /* Initialize temporary slots. */
1306 init_temp_slots (void)
1308 /* We have not allocated any temporaries yet. */
1309 avail_temp_slots
= 0;
1310 used_temp_slots
= 0;
1311 temp_slot_level
= 0;
1313 /* Set up the table to map addresses to temp slots. */
1314 if (! temp_slot_address_table
)
1315 temp_slot_address_table
= htab_create_ggc (32,
1316 temp_slot_address_hash
,
1317 temp_slot_address_eq
,
1320 htab_empty (temp_slot_address_table
);
1323 /* These routines are responsible for converting virtual register references
1324 to the actual hard register references once RTL generation is complete.
1326 The following four variables are used for communication between the
1327 routines. They contain the offsets of the virtual registers from their
1328 respective hard registers. */
1330 static int in_arg_offset
;
1331 static int var_offset
;
1332 static int dynamic_offset
;
1333 static int out_arg_offset
;
1334 static int cfa_offset
;
1336 /* In most machines, the stack pointer register is equivalent to the bottom
1339 #ifndef STACK_POINTER_OFFSET
1340 #define STACK_POINTER_OFFSET 0
1343 /* If not defined, pick an appropriate default for the offset of dynamically
1344 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1345 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1347 #ifndef STACK_DYNAMIC_OFFSET
1349 /* The bottom of the stack points to the actual arguments. If
1350 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1351 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1352 stack space for register parameters is not pushed by the caller, but
1353 rather part of the fixed stack areas and hence not included in
1354 `crtl->outgoing_args_size'. Nevertheless, we must allow
1355 for it when allocating stack dynamic objects. */
1357 #if defined(REG_PARM_STACK_SPACE)
1358 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1359 ((ACCUMULATE_OUTGOING_ARGS \
1360 ? (crtl->outgoing_args_size \
1361 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1362 : REG_PARM_STACK_SPACE (FNDECL))) \
1363 : 0) + (STACK_POINTER_OFFSET))
1365 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1366 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1367 + (STACK_POINTER_OFFSET))
1372 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1373 is a virtual register, return the equivalent hard register and set the
1374 offset indirectly through the pointer. Otherwise, return 0. */
1377 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1380 HOST_WIDE_INT offset
;
1382 if (x
== virtual_incoming_args_rtx
)
1384 if (stack_realign_drap
)
1386 /* Replace virtual_incoming_args_rtx with internal arg
1387 pointer if DRAP is used to realign stack. */
1388 new_rtx
= crtl
->args
.internal_arg_pointer
;
1392 new_rtx
= arg_pointer_rtx
, offset
= in_arg_offset
;
1394 else if (x
== virtual_stack_vars_rtx
)
1395 new_rtx
= frame_pointer_rtx
, offset
= var_offset
;
1396 else if (x
== virtual_stack_dynamic_rtx
)
1397 new_rtx
= stack_pointer_rtx
, offset
= dynamic_offset
;
1398 else if (x
== virtual_outgoing_args_rtx
)
1399 new_rtx
= stack_pointer_rtx
, offset
= out_arg_offset
;
1400 else if (x
== virtual_cfa_rtx
)
1402 #ifdef FRAME_POINTER_CFA_OFFSET
1403 new_rtx
= frame_pointer_rtx
;
1405 new_rtx
= arg_pointer_rtx
;
1407 offset
= cfa_offset
;
1416 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1417 Instantiate any virtual registers present inside of *LOC. The expression
1418 is simplified, as much as possible, but is not to be considered "valid"
1419 in any sense implied by the target. If any change is made, set CHANGED
1423 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1425 HOST_WIDE_INT offset
;
1426 bool *changed
= (bool *) data
;
1433 switch (GET_CODE (x
))
1436 new_rtx
= instantiate_new_reg (x
, &offset
);
1439 *loc
= plus_constant (new_rtx
, offset
);
1446 new_rtx
= instantiate_new_reg (XEXP (x
, 0), &offset
);
1449 new_rtx
= plus_constant (new_rtx
, offset
);
1450 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new_rtx
, XEXP (x
, 1));
1456 /* FIXME -- from old code */
1457 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1458 we can commute the PLUS and SUBREG because pointers into the
1459 frame are well-behaved. */
1469 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1470 matches the predicate for insn CODE operand OPERAND. */
1473 safe_insn_predicate (int code
, int operand
, rtx x
)
1475 const struct insn_operand_data
*op_data
;
1480 op_data
= &insn_data
[code
].operand
[operand
];
1481 if (op_data
->predicate
== NULL
)
1484 return op_data
->predicate (x
, op_data
->mode
);
1487 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1488 registers present inside of insn. The result will be a valid insn. */
1491 instantiate_virtual_regs_in_insn (rtx insn
)
1493 HOST_WIDE_INT offset
;
1495 bool any_change
= false;
1496 rtx set
, new_rtx
, x
, seq
;
1498 /* There are some special cases to be handled first. */
1499 set
= single_set (insn
);
1502 /* We're allowed to assign to a virtual register. This is interpreted
1503 to mean that the underlying register gets assigned the inverse
1504 transformation. This is used, for example, in the handling of
1506 new_rtx
= instantiate_new_reg (SET_DEST (set
), &offset
);
1511 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1512 x
= simplify_gen_binary (PLUS
, GET_MODE (new_rtx
), SET_SRC (set
),
1514 x
= force_operand (x
, new_rtx
);
1516 emit_move_insn (new_rtx
, x
);
1521 emit_insn_before (seq
, insn
);
1526 /* Handle a straight copy from a virtual register by generating a
1527 new add insn. The difference between this and falling through
1528 to the generic case is avoiding a new pseudo and eliminating a
1529 move insn in the initial rtl stream. */
1530 new_rtx
= instantiate_new_reg (SET_SRC (set
), &offset
);
1531 if (new_rtx
&& offset
!= 0
1532 && REG_P (SET_DEST (set
))
1533 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1537 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1538 new_rtx
, GEN_INT (offset
), SET_DEST (set
),
1539 1, OPTAB_LIB_WIDEN
);
1540 if (x
!= SET_DEST (set
))
1541 emit_move_insn (SET_DEST (set
), x
);
1546 emit_insn_before (seq
, insn
);
1551 extract_insn (insn
);
1552 insn_code
= INSN_CODE (insn
);
1554 /* Handle a plus involving a virtual register by determining if the
1555 operands remain valid if they're modified in place. */
1556 if (GET_CODE (SET_SRC (set
)) == PLUS
1557 && recog_data
.n_operands
>= 3
1558 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1559 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1560 && CONST_INT_P (recog_data
.operand
[2])
1561 && (new_rtx
= instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1563 offset
+= INTVAL (recog_data
.operand
[2]);
1565 /* If the sum is zero, then replace with a plain move. */
1567 && REG_P (SET_DEST (set
))
1568 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1571 emit_move_insn (SET_DEST (set
), new_rtx
);
1575 emit_insn_before (seq
, insn
);
1580 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1582 /* Using validate_change and apply_change_group here leaves
1583 recog_data in an invalid state. Since we know exactly what
1584 we want to check, do those two by hand. */
1585 if (safe_insn_predicate (insn_code
, 1, new_rtx
)
1586 && safe_insn_predicate (insn_code
, 2, x
))
1588 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new_rtx
;
1589 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1592 /* Fall through into the regular operand fixup loop in
1593 order to take care of operands other than 1 and 2. */
1599 extract_insn (insn
);
1600 insn_code
= INSN_CODE (insn
);
1603 /* In the general case, we expect virtual registers to appear only in
1604 operands, and then only as either bare registers or inside memories. */
1605 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1607 x
= recog_data
.operand
[i
];
1608 switch (GET_CODE (x
))
1612 rtx addr
= XEXP (x
, 0);
1613 bool changed
= false;
1615 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1620 x
= replace_equiv_address (x
, addr
);
1621 /* It may happen that the address with the virtual reg
1622 was valid (e.g. based on the virtual stack reg, which might
1623 be acceptable to the predicates with all offsets), whereas
1624 the address now isn't anymore, for instance when the address
1625 is still offsetted, but the base reg isn't virtual-stack-reg
1626 anymore. Below we would do a force_reg on the whole operand,
1627 but this insn might actually only accept memory. Hence,
1628 before doing that last resort, try to reload the address into
1629 a register, so this operand stays a MEM. */
1630 if (!safe_insn_predicate (insn_code
, i
, x
))
1632 addr
= force_reg (GET_MODE (addr
), addr
);
1633 x
= replace_equiv_address (x
, addr
);
1638 emit_insn_before (seq
, insn
);
1643 new_rtx
= instantiate_new_reg (x
, &offset
);
1644 if (new_rtx
== NULL
)
1652 /* Careful, special mode predicates may have stuff in
1653 insn_data[insn_code].operand[i].mode that isn't useful
1654 to us for computing a new value. */
1655 /* ??? Recognize address_operand and/or "p" constraints
1656 to see if (plus new offset) is a valid before we put
1657 this through expand_simple_binop. */
1658 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new_rtx
,
1659 GEN_INT (offset
), NULL_RTX
,
1660 1, OPTAB_LIB_WIDEN
);
1663 emit_insn_before (seq
, insn
);
1668 new_rtx
= instantiate_new_reg (SUBREG_REG (x
), &offset
);
1669 if (new_rtx
== NULL
)
1674 new_rtx
= expand_simple_binop (GET_MODE (new_rtx
), PLUS
, new_rtx
,
1675 GEN_INT (offset
), NULL_RTX
,
1676 1, OPTAB_LIB_WIDEN
);
1679 emit_insn_before (seq
, insn
);
1681 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new_rtx
,
1682 GET_MODE (new_rtx
), SUBREG_BYTE (x
));
1690 /* At this point, X contains the new value for the operand.
1691 Validate the new value vs the insn predicate. Note that
1692 asm insns will have insn_code -1 here. */
1693 if (!safe_insn_predicate (insn_code
, i
, x
))
1698 gcc_assert (REGNO (x
) <= LAST_VIRTUAL_REGISTER
);
1699 x
= copy_to_reg (x
);
1702 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1706 emit_insn_before (seq
, insn
);
1709 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1715 /* Propagate operand changes into the duplicates. */
1716 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1717 *recog_data
.dup_loc
[i
]
1718 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1720 /* Force re-recognition of the instruction for validation. */
1721 INSN_CODE (insn
) = -1;
1724 if (asm_noperands (PATTERN (insn
)) >= 0)
1726 if (!check_asm_operands (PATTERN (insn
)))
1728 error_for_asm (insn
, "impossible constraint in %<asm%>");
1734 if (recog_memoized (insn
) < 0)
1735 fatal_insn_not_found (insn
);
1739 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1740 do any instantiation required. */
1743 instantiate_decl_rtl (rtx x
)
1750 /* If this is a CONCAT, recurse for the pieces. */
1751 if (GET_CODE (x
) == CONCAT
)
1753 instantiate_decl_rtl (XEXP (x
, 0));
1754 instantiate_decl_rtl (XEXP (x
, 1));
1758 /* If this is not a MEM, no need to do anything. Similarly if the
1759 address is a constant or a register that is not a virtual register. */
1764 if (CONSTANT_P (addr
)
1766 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1767 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1770 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1773 /* Helper for instantiate_decls called via walk_tree: Process all decls
1774 in the given DECL_VALUE_EXPR. */
1777 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1783 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1784 instantiate_decl_rtl (DECL_RTL (t
));
1789 /* Subroutine of instantiate_decls: Process all decls in the given
1790 BLOCK node and all its subblocks. */
1793 instantiate_decls_1 (tree let
)
1797 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1799 if (DECL_RTL_SET_P (t
))
1800 instantiate_decl_rtl (DECL_RTL (t
));
1801 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1803 tree v
= DECL_VALUE_EXPR (t
);
1804 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1808 /* Process all subblocks. */
1809 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1810 instantiate_decls_1 (t
);
1813 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1814 all virtual registers in their DECL_RTL's. */
1817 instantiate_decls (tree fndecl
)
1821 /* Process all parameters of the function. */
1822 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1824 instantiate_decl_rtl (DECL_RTL (decl
));
1825 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1826 if (DECL_HAS_VALUE_EXPR_P (decl
))
1828 tree v
= DECL_VALUE_EXPR (decl
);
1829 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1833 /* Now process all variables defined in the function or its subblocks. */
1834 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1836 t
= cfun
->local_decls
;
1837 cfun
->local_decls
= NULL_TREE
;
1840 next
= TREE_CHAIN (t
);
1841 decl
= TREE_VALUE (t
);
1842 if (DECL_RTL_SET_P (decl
))
1843 instantiate_decl_rtl (DECL_RTL (decl
));
1848 /* Pass through the INSNS of function FNDECL and convert virtual register
1849 references to hard register references. */
1852 instantiate_virtual_regs (void)
1856 /* Compute the offsets to use for this function. */
1857 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1858 var_offset
= STARTING_FRAME_OFFSET
;
1859 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1860 out_arg_offset
= STACK_POINTER_OFFSET
;
1861 #ifdef FRAME_POINTER_CFA_OFFSET
1862 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1864 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1867 /* Initialize recognition, indicating that volatile is OK. */
1870 /* Scan through all the insns, instantiating every virtual register still
1872 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1875 /* These patterns in the instruction stream can never be recognized.
1876 Fortunately, they shouldn't contain virtual registers either. */
1877 if (GET_CODE (PATTERN (insn
)) == USE
1878 || GET_CODE (PATTERN (insn
)) == CLOBBER
1879 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1880 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1881 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1883 else if (DEBUG_INSN_P (insn
))
1884 for_each_rtx (&INSN_VAR_LOCATION (insn
),
1885 instantiate_virtual_regs_in_rtx
, NULL
);
1887 instantiate_virtual_regs_in_insn (insn
);
1889 if (INSN_DELETED_P (insn
))
1892 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1894 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1896 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1897 instantiate_virtual_regs_in_rtx
, NULL
);
1900 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1901 instantiate_decls (current_function_decl
);
1903 targetm
.instantiate_decls ();
1905 /* Indicate that, from now on, assign_stack_local should use
1906 frame_pointer_rtx. */
1907 virtuals_instantiated
= 1;
1911 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1917 instantiate_virtual_regs
, /* execute */
1920 0, /* static_pass_number */
1921 TV_NONE
, /* tv_id */
1922 0, /* properties_required */
1923 0, /* properties_provided */
1924 0, /* properties_destroyed */
1925 0, /* todo_flags_start */
1926 TODO_dump_func
/* todo_flags_finish */
1931 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1932 This means a type for which function calls must pass an address to the
1933 function or get an address back from the function.
1934 EXP may be a type node or an expression (whose type is tested). */
1937 aggregate_value_p (const_tree exp
, const_tree fntype
)
1939 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1940 int i
, regno
, nregs
;
1944 switch (TREE_CODE (fntype
))
1948 tree fndecl
= get_callee_fndecl (fntype
);
1950 ? TREE_TYPE (fndecl
)
1951 : TREE_TYPE (TREE_TYPE (CALL_EXPR_FN (fntype
))));
1955 fntype
= TREE_TYPE (fntype
);
1960 case IDENTIFIER_NODE
:
1964 /* We don't expect other tree types here. */
1968 if (VOID_TYPE_P (type
))
1971 /* If a record should be passed the same as its first (and only) member
1972 don't pass it as an aggregate. */
1973 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
1974 return aggregate_value_p (first_field (type
), fntype
);
1976 /* If the front end has decided that this needs to be passed by
1977 reference, do so. */
1978 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1979 && DECL_BY_REFERENCE (exp
))
1982 /* Function types that are TREE_ADDRESSABLE force return in memory. */
1983 if (fntype
&& TREE_ADDRESSABLE (fntype
))
1986 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1987 and thus can't be returned in registers. */
1988 if (TREE_ADDRESSABLE (type
))
1991 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1994 if (targetm
.calls
.return_in_memory (type
, fntype
))
1997 /* Make sure we have suitable call-clobbered regs to return
1998 the value in; if not, we must return it in memory. */
1999 reg
= hard_function_value (type
, 0, fntype
, 0);
2001 /* If we have something other than a REG (e.g. a PARALLEL), then assume
2006 regno
= REGNO (reg
);
2007 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
2008 for (i
= 0; i
< nregs
; i
++)
2009 if (! call_used_regs
[regno
+ i
])
2015 /* Return true if we should assign DECL a pseudo register; false if it
2016 should live on the local stack. */
2019 use_register_for_decl (const_tree decl
)
2021 if (!targetm
.calls
.allocate_stack_slots_for_args())
2024 /* Honor volatile. */
2025 if (TREE_SIDE_EFFECTS (decl
))
2028 /* Honor addressability. */
2029 if (TREE_ADDRESSABLE (decl
))
2032 /* Only register-like things go in registers. */
2033 if (DECL_MODE (decl
) == BLKmode
)
2036 /* If -ffloat-store specified, don't put explicit float variables
2038 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
2039 propagates values across these stores, and it probably shouldn't. */
2040 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
2043 /* If we're not interested in tracking debugging information for
2044 this decl, then we can certainly put it in a register. */
2045 if (DECL_IGNORED_P (decl
))
2051 if (!DECL_REGISTER (decl
))
2054 switch (TREE_CODE (TREE_TYPE (decl
)))
2058 case QUAL_UNION_TYPE
:
2059 /* When not optimizing, disregard register keyword for variables with
2060 types containing methods, otherwise the methods won't be callable
2061 from the debugger. */
2062 if (TYPE_METHODS (TREE_TYPE (decl
)))
2072 /* Return true if TYPE should be passed by invisible reference. */
2075 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
2076 tree type
, bool named_arg
)
2080 /* If this type contains non-trivial constructors, then it is
2081 forbidden for the middle-end to create any new copies. */
2082 if (TREE_ADDRESSABLE (type
))
2085 /* GCC post 3.4 passes *all* variable sized types by reference. */
2086 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
2089 /* If a record type should be passed the same as its first (and only)
2090 member, use the type and mode of that member. */
2091 if (TREE_CODE (type
) == RECORD_TYPE
&& TYPE_TRANSPARENT_AGGR (type
))
2093 type
= TREE_TYPE (first_field (type
));
2094 mode
= TYPE_MODE (type
);
2098 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
2101 /* Return true if TYPE, which is passed by reference, should be callee
2102 copied instead of caller copied. */
2105 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
2106 tree type
, bool named_arg
)
2108 if (type
&& TREE_ADDRESSABLE (type
))
2110 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
2113 /* Structures to communicate between the subroutines of assign_parms.
2114 The first holds data persistent across all parameters, the second
2115 is cleared out for each parameter. */
2117 struct assign_parm_data_all
2119 CUMULATIVE_ARGS args_so_far
;
2120 struct args_size stack_args_size
;
2121 tree function_result_decl
;
2123 rtx first_conversion_insn
;
2124 rtx last_conversion_insn
;
2125 HOST_WIDE_INT pretend_args_size
;
2126 HOST_WIDE_INT extra_pretend_bytes
;
2127 int reg_parm_stack_space
;
2130 struct assign_parm_data_one
2136 enum machine_mode nominal_mode
;
2137 enum machine_mode passed_mode
;
2138 enum machine_mode promoted_mode
;
2139 struct locate_and_pad_arg_data locate
;
2141 BOOL_BITFIELD named_arg
: 1;
2142 BOOL_BITFIELD passed_pointer
: 1;
2143 BOOL_BITFIELD on_stack
: 1;
2144 BOOL_BITFIELD loaded_in_reg
: 1;
2147 /* A subroutine of assign_parms. Initialize ALL. */
2150 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
2152 tree fntype ATTRIBUTE_UNUSED
;
2154 memset (all
, 0, sizeof (*all
));
2156 fntype
= TREE_TYPE (current_function_decl
);
2158 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
2159 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
2161 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
2162 current_function_decl
, -1);
2165 #ifdef REG_PARM_STACK_SPACE
2166 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
2170 /* If ARGS contains entries with complex types, split the entry into two
2171 entries of the component type. Return a new list of substitutions are
2172 needed, else the old list. */
2175 split_complex_args (VEC(tree
, heap
) **args
)
2180 for (i
= 0; VEC_iterate (tree
, *args
, i
, p
); ++i
)
2182 tree type
= TREE_TYPE (p
);
2183 if (TREE_CODE (type
) == COMPLEX_TYPE
2184 && targetm
.calls
.split_complex_arg (type
))
2187 tree subtype
= TREE_TYPE (type
);
2188 bool addressable
= TREE_ADDRESSABLE (p
);
2190 /* Rewrite the PARM_DECL's type with its component. */
2192 TREE_TYPE (p
) = subtype
;
2193 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
2194 DECL_MODE (p
) = VOIDmode
;
2195 DECL_SIZE (p
) = NULL
;
2196 DECL_SIZE_UNIT (p
) = NULL
;
2197 /* If this arg must go in memory, put it in a pseudo here.
2198 We can't allow it to go in memory as per normal parms,
2199 because the usual place might not have the imag part
2200 adjacent to the real part. */
2201 DECL_ARTIFICIAL (p
) = addressable
;
2202 DECL_IGNORED_P (p
) = addressable
;
2203 TREE_ADDRESSABLE (p
) = 0;
2205 VEC_replace (tree
, *args
, i
, p
);
2207 /* Build a second synthetic decl. */
2208 decl
= build_decl (EXPR_LOCATION (p
),
2209 PARM_DECL
, NULL_TREE
, subtype
);
2210 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
2211 DECL_ARTIFICIAL (decl
) = addressable
;
2212 DECL_IGNORED_P (decl
) = addressable
;
2213 layout_decl (decl
, 0);
2214 VEC_safe_insert (tree
, heap
, *args
, ++i
, decl
);
2219 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
2220 the hidden struct return argument, and (abi willing) complex args.
2221 Return the new parameter list. */
2223 static VEC(tree
, heap
) *
2224 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
2226 tree fndecl
= current_function_decl
;
2227 tree fntype
= TREE_TYPE (fndecl
);
2228 VEC(tree
, heap
) *fnargs
= NULL
;
2231 for (arg
= DECL_ARGUMENTS (fndecl
); arg
; arg
= TREE_CHAIN (arg
))
2232 VEC_safe_push (tree
, heap
, fnargs
, arg
);
2234 all
->orig_fnargs
= DECL_ARGUMENTS (fndecl
);
2236 /* If struct value address is treated as the first argument, make it so. */
2237 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
2238 && ! cfun
->returns_pcc_struct
2239 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
2241 tree type
= build_pointer_type (TREE_TYPE (fntype
));
2244 decl
= build_decl (DECL_SOURCE_LOCATION (fndecl
),
2245 PARM_DECL
, NULL_TREE
, type
);
2246 DECL_ARG_TYPE (decl
) = type
;
2247 DECL_ARTIFICIAL (decl
) = 1;
2248 DECL_IGNORED_P (decl
) = 1;
2250 TREE_CHAIN (decl
) = all
->orig_fnargs
;
2251 all
->orig_fnargs
= decl
;
2252 VEC_safe_insert (tree
, heap
, fnargs
, 0, decl
);
2254 all
->function_result_decl
= decl
;
2257 /* If the target wants to split complex arguments into scalars, do so. */
2258 if (targetm
.calls
.split_complex_arg
)
2259 split_complex_args (&fnargs
);
2264 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2265 data for the parameter. Incorporate ABI specifics such as pass-by-
2266 reference and type promotion. */
2269 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2270 struct assign_parm_data_one
*data
)
2272 tree nominal_type
, passed_type
;
2273 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2276 memset (data
, 0, sizeof (*data
));
2278 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2280 data
->named_arg
= 1; /* No variadic parms. */
2281 else if (TREE_CHAIN (parm
))
2282 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2283 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2284 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2286 data
->named_arg
= 0; /* Treat as variadic. */
2288 nominal_type
= TREE_TYPE (parm
);
2289 passed_type
= DECL_ARG_TYPE (parm
);
2291 /* Look out for errors propagating this far. Also, if the parameter's
2292 type is void then its value doesn't matter. */
2293 if (TREE_TYPE (parm
) == error_mark_node
2294 /* This can happen after weird syntax errors
2295 or if an enum type is defined among the parms. */
2296 || TREE_CODE (parm
) != PARM_DECL
2297 || passed_type
== NULL
2298 || VOID_TYPE_P (nominal_type
))
2300 nominal_type
= passed_type
= void_type_node
;
2301 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2305 /* Find mode of arg as it is passed, and mode of arg as it should be
2306 during execution of this function. */
2307 passed_mode
= TYPE_MODE (passed_type
);
2308 nominal_mode
= TYPE_MODE (nominal_type
);
2310 /* If the parm is to be passed as a transparent union or record, use the
2311 type of the first field for the tests below. We have already verified
2312 that the modes are the same. */
2313 if ((TREE_CODE (passed_type
) == UNION_TYPE
2314 || TREE_CODE (passed_type
) == RECORD_TYPE
)
2315 && TYPE_TRANSPARENT_AGGR (passed_type
))
2316 passed_type
= TREE_TYPE (first_field (passed_type
));
2318 /* See if this arg was passed by invisible reference. */
2319 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2320 passed_type
, data
->named_arg
))
2322 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2323 data
->passed_pointer
= true;
2324 passed_mode
= nominal_mode
= Pmode
;
2327 /* Find mode as it is passed by the ABI. */
2328 unsignedp
= TYPE_UNSIGNED (passed_type
);
2329 promoted_mode
= promote_function_mode (passed_type
, passed_mode
, &unsignedp
,
2330 TREE_TYPE (current_function_decl
), 0);
2333 data
->nominal_type
= nominal_type
;
2334 data
->passed_type
= passed_type
;
2335 data
->nominal_mode
= nominal_mode
;
2336 data
->passed_mode
= passed_mode
;
2337 data
->promoted_mode
= promoted_mode
;
2340 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2343 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2344 struct assign_parm_data_one
*data
, bool no_rtl
)
2346 int varargs_pretend_bytes
= 0;
2348 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2349 data
->promoted_mode
,
2351 &varargs_pretend_bytes
, no_rtl
);
2353 /* If the back-end has requested extra stack space, record how much is
2354 needed. Do not change pretend_args_size otherwise since it may be
2355 nonzero from an earlier partial argument. */
2356 if (varargs_pretend_bytes
> 0)
2357 all
->pretend_args_size
= varargs_pretend_bytes
;
2360 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2361 the incoming location of the current parameter. */
2364 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2365 struct assign_parm_data_one
*data
)
2367 HOST_WIDE_INT pretend_bytes
= 0;
2371 if (data
->promoted_mode
== VOIDmode
)
2373 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2377 #ifdef FUNCTION_INCOMING_ARG
2378 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2379 data
->passed_type
, data
->named_arg
);
2381 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2382 data
->passed_type
, data
->named_arg
);
2385 if (entry_parm
== 0)
2386 data
->promoted_mode
= data
->passed_mode
;
2388 /* Determine parm's home in the stack, in case it arrives in the stack
2389 or we should pretend it did. Compute the stack position and rtx where
2390 the argument arrives and its size.
2392 There is one complexity here: If this was a parameter that would
2393 have been passed in registers, but wasn't only because it is
2394 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2395 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2396 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2397 as it was the previous time. */
2398 in_regs
= entry_parm
!= 0;
2399 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2402 if (!in_regs
&& !data
->named_arg
)
2404 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2407 #ifdef FUNCTION_INCOMING_ARG
2408 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2409 data
->passed_type
, true);
2411 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2412 data
->passed_type
, true);
2414 in_regs
= tem
!= NULL
;
2418 /* If this parameter was passed both in registers and in the stack, use
2419 the copy on the stack. */
2420 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2428 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2429 data
->promoted_mode
,
2432 data
->partial
= partial
;
2434 /* The caller might already have allocated stack space for the
2435 register parameters. */
2436 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2438 /* Part of this argument is passed in registers and part
2439 is passed on the stack. Ask the prologue code to extend
2440 the stack part so that we can recreate the full value.
2442 PRETEND_BYTES is the size of the registers we need to store.
2443 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2444 stack space that the prologue should allocate.
2446 Internally, gcc assumes that the argument pointer is aligned
2447 to STACK_BOUNDARY bits. This is used both for alignment
2448 optimizations (see init_emit) and to locate arguments that are
2449 aligned to more than PARM_BOUNDARY bits. We must preserve this
2450 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2451 a stack boundary. */
2453 /* We assume at most one partial arg, and it must be the first
2454 argument on the stack. */
2455 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2457 pretend_bytes
= partial
;
2458 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2460 /* We want to align relative to the actual stack pointer, so
2461 don't include this in the stack size until later. */
2462 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2466 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2467 entry_parm
? data
->partial
: 0, current_function_decl
,
2468 &all
->stack_args_size
, &data
->locate
);
2470 /* Update parm_stack_boundary if this parameter is passed in the
2472 if (!in_regs
&& crtl
->parm_stack_boundary
< data
->locate
.boundary
)
2473 crtl
->parm_stack_boundary
= data
->locate
.boundary
;
2475 /* Adjust offsets to include the pretend args. */
2476 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2477 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2478 data
->locate
.offset
.constant
+= pretend_bytes
;
2480 data
->entry_parm
= entry_parm
;
2483 /* A subroutine of assign_parms. If there is actually space on the stack
2484 for this parm, count it in stack_args_size and return true. */
2487 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2488 struct assign_parm_data_one
*data
)
2490 /* Trivially true if we've no incoming register. */
2491 if (data
->entry_parm
== NULL
)
2493 /* Also true if we're partially in registers and partially not,
2494 since we've arranged to drop the entire argument on the stack. */
2495 else if (data
->partial
!= 0)
2497 /* Also true if the target says that it's passed in both registers
2498 and on the stack. */
2499 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2500 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2502 /* Also true if the target says that there's stack allocated for
2503 all register parameters. */
2504 else if (all
->reg_parm_stack_space
> 0)
2506 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2510 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2511 if (data
->locate
.size
.var
)
2512 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2517 /* A subroutine of assign_parms. Given that this parameter is allocated
2518 stack space by the ABI, find it. */
2521 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2523 rtx offset_rtx
, stack_parm
;
2524 unsigned int align
, boundary
;
2526 /* If we're passing this arg using a reg, make its stack home the
2527 aligned stack slot. */
2528 if (data
->entry_parm
)
2529 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2531 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2533 stack_parm
= crtl
->args
.internal_arg_pointer
;
2534 if (offset_rtx
!= const0_rtx
)
2535 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2536 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2538 if (!data
->passed_pointer
)
2540 set_mem_attributes (stack_parm
, parm
, 1);
2541 /* set_mem_attributes could set MEM_SIZE to the passed mode's size,
2542 while promoted mode's size is needed. */
2543 if (data
->promoted_mode
!= BLKmode
2544 && data
->promoted_mode
!= DECL_MODE (parm
))
2546 set_mem_size (stack_parm
,
2547 GEN_INT (GET_MODE_SIZE (data
->promoted_mode
)));
2548 if (MEM_EXPR (stack_parm
) && MEM_OFFSET (stack_parm
))
2550 int offset
= subreg_lowpart_offset (DECL_MODE (parm
),
2551 data
->promoted_mode
);
2553 set_mem_offset (stack_parm
,
2554 plus_constant (MEM_OFFSET (stack_parm
),
2560 boundary
= data
->locate
.boundary
;
2561 align
= BITS_PER_UNIT
;
2563 /* If we're padding upward, we know that the alignment of the slot
2564 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2565 intentionally forcing upward padding. Otherwise we have to come
2566 up with a guess at the alignment based on OFFSET_RTX. */
2567 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2569 else if (CONST_INT_P (offset_rtx
))
2571 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2572 align
= align
& -align
;
2574 set_mem_align (stack_parm
, align
);
2576 if (data
->entry_parm
)
2577 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2579 data
->stack_parm
= stack_parm
;
2582 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2583 always valid and contiguous. */
2586 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2588 rtx entry_parm
= data
->entry_parm
;
2589 rtx stack_parm
= data
->stack_parm
;
2591 /* If this parm was passed part in regs and part in memory, pretend it
2592 arrived entirely in memory by pushing the register-part onto the stack.
2593 In the special case of a DImode or DFmode that is split, we could put
2594 it together in a pseudoreg directly, but for now that's not worth
2596 if (data
->partial
!= 0)
2598 /* Handle calls that pass values in multiple non-contiguous
2599 locations. The Irix 6 ABI has examples of this. */
2600 if (GET_CODE (entry_parm
) == PARALLEL
)
2601 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2603 int_size_in_bytes (data
->passed_type
));
2606 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2607 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2608 data
->partial
/ UNITS_PER_WORD
);
2611 entry_parm
= stack_parm
;
2614 /* If we didn't decide this parm came in a register, by default it came
2616 else if (entry_parm
== NULL
)
2617 entry_parm
= stack_parm
;
2619 /* When an argument is passed in multiple locations, we can't make use
2620 of this information, but we can save some copying if the whole argument
2621 is passed in a single register. */
2622 else if (GET_CODE (entry_parm
) == PARALLEL
2623 && data
->nominal_mode
!= BLKmode
2624 && data
->passed_mode
!= BLKmode
)
2626 size_t i
, len
= XVECLEN (entry_parm
, 0);
2628 for (i
= 0; i
< len
; i
++)
2629 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2630 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2631 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2632 == data
->passed_mode
)
2633 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2635 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2640 data
->entry_parm
= entry_parm
;
2643 /* A subroutine of assign_parms. Reconstitute any values which were
2644 passed in multiple registers and would fit in a single register. */
2647 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2649 rtx entry_parm
= data
->entry_parm
;
2651 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2652 This can be done with register operations rather than on the
2653 stack, even if we will store the reconstituted parameter on the
2655 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2657 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2658 emit_group_store (parmreg
, entry_parm
, data
->passed_type
,
2659 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2660 entry_parm
= parmreg
;
2663 data
->entry_parm
= entry_parm
;
2666 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2667 always valid and properly aligned. */
2670 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2672 rtx stack_parm
= data
->stack_parm
;
2674 /* If we can't trust the parm stack slot to be aligned enough for its
2675 ultimate type, don't use that slot after entry. We'll make another
2676 stack slot, if we need one. */
2678 && ((STRICT_ALIGNMENT
2679 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2680 || (data
->nominal_type
2681 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2682 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2685 /* If parm was passed in memory, and we need to convert it on entry,
2686 don't store it back in that same slot. */
2687 else if (data
->entry_parm
== stack_parm
2688 && data
->nominal_mode
!= BLKmode
2689 && data
->nominal_mode
!= data
->passed_mode
)
2692 /* If stack protection is in effect for this function, don't leave any
2693 pointers in their passed stack slots. */
2694 else if (crtl
->stack_protect_guard
2695 && (flag_stack_protect
== 2
2696 || data
->passed_pointer
2697 || POINTER_TYPE_P (data
->nominal_type
)))
2700 data
->stack_parm
= stack_parm
;
2703 /* A subroutine of assign_parms. Return true if the current parameter
2704 should be stored as a BLKmode in the current frame. */
2707 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2709 if (data
->nominal_mode
== BLKmode
)
2711 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2714 #ifdef BLOCK_REG_PADDING
2715 /* Only assign_parm_setup_block knows how to deal with register arguments
2716 that are padded at the least significant end. */
2717 if (REG_P (data
->entry_parm
)
2718 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2719 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2720 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2727 /* A subroutine of assign_parms. Arrange for the parameter to be
2728 present and valid in DATA->STACK_RTL. */
2731 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2732 tree parm
, struct assign_parm_data_one
*data
)
2734 rtx entry_parm
= data
->entry_parm
;
2735 rtx stack_parm
= data
->stack_parm
;
2737 HOST_WIDE_INT size_stored
;
2739 if (GET_CODE (entry_parm
) == PARALLEL
)
2740 entry_parm
= emit_group_move_into_temps (entry_parm
);
2742 size
= int_size_in_bytes (data
->passed_type
);
2743 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2744 if (stack_parm
== 0)
2746 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2747 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2749 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2750 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2751 set_mem_attributes (stack_parm
, parm
, 1);
2754 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2755 calls that pass values in multiple non-contiguous locations. */
2756 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2760 /* Note that we will be storing an integral number of words.
2761 So we have to be careful to ensure that we allocate an
2762 integral number of words. We do this above when we call
2763 assign_stack_local if space was not allocated in the argument
2764 list. If it was, this will not work if PARM_BOUNDARY is not
2765 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2766 if it becomes a problem. Exception is when BLKmode arrives
2767 with arguments not conforming to word_mode. */
2769 if (data
->stack_parm
== 0)
2771 else if (GET_CODE (entry_parm
) == PARALLEL
)
2774 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2776 mem
= validize_mem (stack_parm
);
2778 /* Handle values in multiple non-contiguous locations. */
2779 if (GET_CODE (entry_parm
) == PARALLEL
)
2781 push_to_sequence2 (all
->first_conversion_insn
,
2782 all
->last_conversion_insn
);
2783 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2784 all
->first_conversion_insn
= get_insns ();
2785 all
->last_conversion_insn
= get_last_insn ();
2792 /* If SIZE is that of a mode no bigger than a word, just use
2793 that mode's store operation. */
2794 else if (size
<= UNITS_PER_WORD
)
2796 enum machine_mode mode
2797 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2800 #ifdef BLOCK_REG_PADDING
2801 && (size
== UNITS_PER_WORD
2802 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2803 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2809 /* We are really truncating a word_mode value containing
2810 SIZE bytes into a value of mode MODE. If such an
2811 operation requires no actual instructions, we can refer
2812 to the value directly in mode MODE, otherwise we must
2813 start with the register in word_mode and explicitly
2815 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2816 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2819 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2820 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2822 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2825 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2826 machine must be aligned to the left before storing
2827 to memory. Note that the previous test doesn't
2828 handle all cases (e.g. SIZE == 3). */
2829 else if (size
!= UNITS_PER_WORD
2830 #ifdef BLOCK_REG_PADDING
2831 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2839 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2840 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2842 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2843 build_int_cst (NULL_TREE
, by
),
2845 tem
= change_address (mem
, word_mode
, 0);
2846 emit_move_insn (tem
, x
);
2849 move_block_from_reg (REGNO (entry_parm
), mem
,
2850 size_stored
/ UNITS_PER_WORD
);
2853 move_block_from_reg (REGNO (entry_parm
), mem
,
2854 size_stored
/ UNITS_PER_WORD
);
2856 else if (data
->stack_parm
== 0)
2858 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2859 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2861 all
->first_conversion_insn
= get_insns ();
2862 all
->last_conversion_insn
= get_last_insn ();
2866 data
->stack_parm
= stack_parm
;
2867 SET_DECL_RTL (parm
, stack_parm
);
2870 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2871 parameter. Get it there. Perform all ABI specified conversions. */
2874 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2875 struct assign_parm_data_one
*data
)
2878 enum machine_mode promoted_nominal_mode
;
2879 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2880 bool did_conversion
= false;
2882 /* Store the parm in a pseudoregister during the function, but we may
2883 need to do it in a wider mode. Using 2 here makes the result
2884 consistent with promote_decl_mode and thus expand_expr_real_1. */
2885 promoted_nominal_mode
2886 = promote_function_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
,
2887 TREE_TYPE (current_function_decl
), 2);
2889 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2891 if (!DECL_ARTIFICIAL (parm
))
2892 mark_user_reg (parmreg
);
2894 /* If this was an item that we received a pointer to,
2895 set DECL_RTL appropriately. */
2896 if (data
->passed_pointer
)
2898 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2899 set_mem_attributes (x
, parm
, 1);
2900 SET_DECL_RTL (parm
, x
);
2903 SET_DECL_RTL (parm
, parmreg
);
2905 assign_parm_remove_parallels (data
);
2907 /* Copy the value into the register, thus bridging between
2908 assign_parm_find_data_types and expand_expr_real_1. */
2909 if (data
->nominal_mode
!= data
->passed_mode
2910 || promoted_nominal_mode
!= data
->promoted_mode
)
2914 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2915 mode, by the caller. We now have to convert it to
2916 NOMINAL_MODE, if different. However, PARMREG may be in
2917 a different mode than NOMINAL_MODE if it is being stored
2920 If ENTRY_PARM is a hard register, it might be in a register
2921 not valid for operating in its mode (e.g., an odd-numbered
2922 register for a DFmode). In that case, moves are the only
2923 thing valid, so we can't do a convert from there. This
2924 occurs when the calling sequence allow such misaligned
2927 In addition, the conversion may involve a call, which could
2928 clobber parameters which haven't been copied to pseudo
2929 registers yet. Therefore, we must first copy the parm to
2930 a pseudo reg here, and save the conversion until after all
2931 parameters have been moved. */
2933 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2935 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2937 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2938 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2940 if (GET_CODE (tempreg
) == SUBREG
2941 && GET_MODE (tempreg
) == data
->nominal_mode
2942 && REG_P (SUBREG_REG (tempreg
))
2943 && data
->nominal_mode
== data
->passed_mode
2944 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2945 && GET_MODE_SIZE (GET_MODE (tempreg
))
2946 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2948 /* The argument is already sign/zero extended, so note it
2950 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2951 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2954 /* TREE_USED gets set erroneously during expand_assignment. */
2955 save_tree_used
= TREE_USED (parm
);
2956 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2957 TREE_USED (parm
) = save_tree_used
;
2958 all
->first_conversion_insn
= get_insns ();
2959 all
->last_conversion_insn
= get_last_insn ();
2962 did_conversion
= true;
2965 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2967 /* If we were passed a pointer but the actual value can safely live
2968 in a register, put it in one. */
2969 if (data
->passed_pointer
2970 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2971 /* If by-reference argument was promoted, demote it. */
2972 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2973 || use_register_for_decl (parm
)))
2975 /* We can't use nominal_mode, because it will have been set to
2976 Pmode above. We must use the actual mode of the parm. */
2977 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2978 mark_user_reg (parmreg
);
2980 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2982 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2983 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2985 push_to_sequence2 (all
->first_conversion_insn
,
2986 all
->last_conversion_insn
);
2987 emit_move_insn (tempreg
, DECL_RTL (parm
));
2988 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2989 emit_move_insn (parmreg
, tempreg
);
2990 all
->first_conversion_insn
= get_insns ();
2991 all
->last_conversion_insn
= get_last_insn ();
2994 did_conversion
= true;
2997 emit_move_insn (parmreg
, DECL_RTL (parm
));
2999 SET_DECL_RTL (parm
, parmreg
);
3001 /* STACK_PARM is the pointer, not the parm, and PARMREG is
3003 data
->stack_parm
= NULL
;
3006 /* Mark the register as eliminable if we did no conversion and it was
3007 copied from memory at a fixed offset, and the arg pointer was not
3008 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
3009 offset formed an invalid address, such memory-equivalences as we
3010 make here would screw up life analysis for it. */
3011 if (data
->nominal_mode
== data
->passed_mode
3013 && data
->stack_parm
!= 0
3014 && MEM_P (data
->stack_parm
)
3015 && data
->locate
.offset
.var
== 0
3016 && reg_mentioned_p (virtual_incoming_args_rtx
,
3017 XEXP (data
->stack_parm
, 0)))
3019 rtx linsn
= get_last_insn ();
3022 /* Mark complex types separately. */
3023 if (GET_CODE (parmreg
) == CONCAT
)
3025 enum machine_mode submode
3026 = GET_MODE_INNER (GET_MODE (parmreg
));
3027 int regnor
= REGNO (XEXP (parmreg
, 0));
3028 int regnoi
= REGNO (XEXP (parmreg
, 1));
3029 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
3030 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
3031 GET_MODE_SIZE (submode
));
3033 /* Scan backwards for the set of the real and
3035 for (sinsn
= linsn
; sinsn
!= 0;
3036 sinsn
= prev_nonnote_insn (sinsn
))
3038 set
= single_set (sinsn
);
3042 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
3043 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
3044 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
3045 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
3048 else if ((set
= single_set (linsn
)) != 0
3049 && SET_DEST (set
) == parmreg
)
3050 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
3053 /* For pointer data type, suggest pointer register. */
3054 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
3055 mark_reg_pointer (parmreg
,
3056 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
3059 /* A subroutine of assign_parms. Allocate stack space to hold the current
3060 parameter. Get it there. Perform all ABI specified conversions. */
3063 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
3064 struct assign_parm_data_one
*data
)
3066 /* Value must be stored in the stack slot STACK_PARM during function
3068 bool to_conversion
= false;
3070 assign_parm_remove_parallels (data
);
3072 if (data
->promoted_mode
!= data
->nominal_mode
)
3074 /* Conversion is required. */
3075 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
3077 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
3079 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
3080 to_conversion
= true;
3082 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
3083 TYPE_UNSIGNED (TREE_TYPE (parm
)));
3085 if (data
->stack_parm
)
3087 int offset
= subreg_lowpart_offset (data
->nominal_mode
,
3088 GET_MODE (data
->stack_parm
));
3089 /* ??? This may need a big-endian conversion on sparc64. */
3091 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
3092 if (offset
&& MEM_OFFSET (data
->stack_parm
))
3093 set_mem_offset (data
->stack_parm
,
3094 plus_constant (MEM_OFFSET (data
->stack_parm
),
3099 if (data
->entry_parm
!= data
->stack_parm
)
3103 if (data
->stack_parm
== 0)
3105 int align
= STACK_SLOT_ALIGNMENT (data
->passed_type
,
3106 GET_MODE (data
->entry_parm
),
3107 TYPE_ALIGN (data
->passed_type
));
3109 = assign_stack_local (GET_MODE (data
->entry_parm
),
3110 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
3112 set_mem_attributes (data
->stack_parm
, parm
, 1);
3115 dest
= validize_mem (data
->stack_parm
);
3116 src
= validize_mem (data
->entry_parm
);
3120 /* Use a block move to handle potentially misaligned entry_parm. */
3122 push_to_sequence2 (all
->first_conversion_insn
,
3123 all
->last_conversion_insn
);
3124 to_conversion
= true;
3126 emit_block_move (dest
, src
,
3127 GEN_INT (int_size_in_bytes (data
->passed_type
)),
3131 emit_move_insn (dest
, src
);
3136 all
->first_conversion_insn
= get_insns ();
3137 all
->last_conversion_insn
= get_last_insn ();
3141 SET_DECL_RTL (parm
, data
->stack_parm
);
3144 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
3145 undo the frobbing that we did in assign_parms_augmented_arg_list. */
3148 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
,
3149 VEC(tree
, heap
) *fnargs
)
3152 tree orig_fnargs
= all
->orig_fnargs
;
3155 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
), ++i
)
3157 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
3158 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
3160 rtx tmp
, real
, imag
;
3161 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
3163 real
= DECL_RTL (VEC_index (tree
, fnargs
, i
));
3164 imag
= DECL_RTL (VEC_index (tree
, fnargs
, i
+ 1));
3165 if (inner
!= GET_MODE (real
))
3167 real
= gen_lowpart_SUBREG (inner
, real
);
3168 imag
= gen_lowpart_SUBREG (inner
, imag
);
3171 if (TREE_ADDRESSABLE (parm
))
3174 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
3175 int align
= STACK_SLOT_ALIGNMENT (TREE_TYPE (parm
),
3177 TYPE_ALIGN (TREE_TYPE (parm
)));
3179 /* split_complex_arg put the real and imag parts in
3180 pseudos. Move them to memory. */
3181 tmp
= assign_stack_local (DECL_MODE (parm
), size
, align
);
3182 set_mem_attributes (tmp
, parm
, 1);
3183 rmem
= adjust_address_nv (tmp
, inner
, 0);
3184 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
3185 push_to_sequence2 (all
->first_conversion_insn
,
3186 all
->last_conversion_insn
);
3187 emit_move_insn (rmem
, real
);
3188 emit_move_insn (imem
, imag
);
3189 all
->first_conversion_insn
= get_insns ();
3190 all
->last_conversion_insn
= get_last_insn ();
3194 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3195 SET_DECL_RTL (parm
, tmp
);
3197 real
= DECL_INCOMING_RTL (VEC_index (tree
, fnargs
, i
));
3198 imag
= DECL_INCOMING_RTL (VEC_index (tree
, fnargs
, i
+ 1));
3199 if (inner
!= GET_MODE (real
))
3201 real
= gen_lowpart_SUBREG (inner
, real
);
3202 imag
= gen_lowpart_SUBREG (inner
, imag
);
3204 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
3205 set_decl_incoming_rtl (parm
, tmp
, false);
3211 /* Assign RTL expressions to the function's parameters. This may involve
3212 copying them into registers and using those registers as the DECL_RTL. */
3215 assign_parms (tree fndecl
)
3217 struct assign_parm_data_all all
;
3219 VEC(tree
, heap
) *fnargs
;
3222 crtl
->args
.internal_arg_pointer
3223 = targetm
.calls
.internal_arg_pointer ();
3225 assign_parms_initialize_all (&all
);
3226 fnargs
= assign_parms_augmented_arg_list (&all
);
3228 for (i
= 0; VEC_iterate (tree
, fnargs
, i
, parm
); ++i
)
3230 struct assign_parm_data_one data
;
3232 /* Extract the type of PARM; adjust it according to ABI. */
3233 assign_parm_find_data_types (&all
, parm
, &data
);
3235 /* Early out for errors and void parameters. */
3236 if (data
.passed_mode
== VOIDmode
)
3238 SET_DECL_RTL (parm
, const0_rtx
);
3239 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
3243 /* Estimate stack alignment from parameter alignment. */
3244 if (SUPPORTS_STACK_ALIGNMENT
)
3246 unsigned int align
= FUNCTION_ARG_BOUNDARY (data
.promoted_mode
,
3248 align
= MINIMUM_ALIGNMENT (data
.passed_type
, data
.promoted_mode
,
3250 if (TYPE_ALIGN (data
.nominal_type
) > align
)
3251 align
= MINIMUM_ALIGNMENT (data
.nominal_type
,
3252 TYPE_MODE (data
.nominal_type
),
3253 TYPE_ALIGN (data
.nominal_type
));
3254 if (crtl
->stack_alignment_estimated
< align
)
3256 gcc_assert (!crtl
->stack_realign_processed
);
3257 crtl
->stack_alignment_estimated
= align
;
3261 if (cfun
->stdarg
&& !TREE_CHAIN (parm
))
3262 assign_parms_setup_varargs (&all
, &data
, false);
3264 /* Find out where the parameter arrives in this function. */
3265 assign_parm_find_entry_rtl (&all
, &data
);
3267 /* Find out where stack space for this parameter might be. */
3268 if (assign_parm_is_stack_parm (&all
, &data
))
3270 assign_parm_find_stack_rtl (parm
, &data
);
3271 assign_parm_adjust_entry_rtl (&data
);
3274 /* Record permanently how this parm was passed. */
3275 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
3277 /* Update info on where next arg arrives in registers. */
3278 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3279 data
.passed_type
, data
.named_arg
);
3281 assign_parm_adjust_stack_rtl (&data
);
3283 if (assign_parm_setup_block_p (&data
))
3284 assign_parm_setup_block (&all
, parm
, &data
);
3285 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
3286 assign_parm_setup_reg (&all
, parm
, &data
);
3288 assign_parm_setup_stack (&all
, parm
, &data
);
3291 if (targetm
.calls
.split_complex_arg
)
3292 assign_parms_unsplit_complex (&all
, fnargs
);
3294 VEC_free (tree
, heap
, fnargs
);
3296 /* Output all parameter conversion instructions (possibly including calls)
3297 now that all parameters have been copied out of hard registers. */
3298 emit_insn (all
.first_conversion_insn
);
3300 /* Estimate reload stack alignment from scalar return mode. */
3301 if (SUPPORTS_STACK_ALIGNMENT
)
3303 if (DECL_RESULT (fndecl
))
3305 tree type
= TREE_TYPE (DECL_RESULT (fndecl
));
3306 enum machine_mode mode
= TYPE_MODE (type
);
3310 && !AGGREGATE_TYPE_P (type
))
3312 unsigned int align
= GET_MODE_ALIGNMENT (mode
);
3313 if (crtl
->stack_alignment_estimated
< align
)
3315 gcc_assert (!crtl
->stack_realign_processed
);
3316 crtl
->stack_alignment_estimated
= align
;
3322 /* If we are receiving a struct value address as the first argument, set up
3323 the RTL for the function result. As this might require code to convert
3324 the transmitted address to Pmode, we do this here to ensure that possible
3325 preliminary conversions of the address have been emitted already. */
3326 if (all
.function_result_decl
)
3328 tree result
= DECL_RESULT (current_function_decl
);
3329 rtx addr
= DECL_RTL (all
.function_result_decl
);
3332 if (DECL_BY_REFERENCE (result
))
3336 addr
= convert_memory_address (Pmode
, addr
);
3337 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3338 set_mem_attributes (x
, result
, 1);
3340 SET_DECL_RTL (result
, x
);
3343 /* We have aligned all the args, so add space for the pretend args. */
3344 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3345 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3346 crtl
->args
.size
= all
.stack_args_size
.constant
;
3348 /* Adjust function incoming argument size for alignment and
3351 #ifdef REG_PARM_STACK_SPACE
3352 crtl
->args
.size
= MAX (crtl
->args
.size
,
3353 REG_PARM_STACK_SPACE (fndecl
));
3356 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3357 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3359 #ifdef ARGS_GROW_DOWNWARD
3360 crtl
->args
.arg_offset_rtx
3361 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3362 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3363 size_int (-all
.stack_args_size
.constant
)),
3364 NULL_RTX
, VOIDmode
, EXPAND_NORMAL
));
3366 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3369 /* See how many bytes, if any, of its args a function should try to pop
3372 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3375 /* For stdarg.h function, save info about
3376 regs and stack space used by the named args. */
3378 crtl
->args
.info
= all
.args_so_far
;
3380 /* Set the rtx used for the function return value. Put this in its
3381 own variable so any optimizers that need this information don't have
3382 to include tree.h. Do this here so it gets done when an inlined
3383 function gets output. */
3386 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3387 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3389 /* If scalar return value was computed in a pseudo-reg, or was a named
3390 return value that got dumped to the stack, copy that to the hard
3392 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3394 tree decl_result
= DECL_RESULT (fndecl
);
3395 rtx decl_rtl
= DECL_RTL (decl_result
);
3397 if (REG_P (decl_rtl
)
3398 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3399 : DECL_REGISTER (decl_result
))
3403 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3405 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3406 /* The delay slot scheduler assumes that crtl->return_rtx
3407 holds the hard register containing the return value, not a
3408 temporary pseudo. */
3409 crtl
->return_rtx
= real_decl_rtl
;
3414 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3415 For all seen types, gimplify their sizes. */
3418 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3425 if (POINTER_TYPE_P (t
))
3427 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3428 && !TYPE_SIZES_GIMPLIFIED (t
))
3430 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3438 /* Gimplify the parameter list for current_function_decl. This involves
3439 evaluating SAVE_EXPRs of variable sized parameters and generating code
3440 to implement callee-copies reference parameters. Returns a sequence of
3441 statements to add to the beginning of the function. */
3444 gimplify_parameters (void)
3446 struct assign_parm_data_all all
;
3448 gimple_seq stmts
= NULL
;
3449 VEC(tree
, heap
) *fnargs
;
3452 assign_parms_initialize_all (&all
);
3453 fnargs
= assign_parms_augmented_arg_list (&all
);
3455 for (i
= 0; VEC_iterate (tree
, fnargs
, i
, parm
); ++i
)
3457 struct assign_parm_data_one data
;
3459 /* Extract the type of PARM; adjust it according to ABI. */
3460 assign_parm_find_data_types (&all
, parm
, &data
);
3462 /* Early out for errors and void parameters. */
3463 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3466 /* Update info on where next arg arrives in registers. */
3467 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3468 data
.passed_type
, data
.named_arg
);
3470 /* ??? Once upon a time variable_size stuffed parameter list
3471 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3472 turned out to be less than manageable in the gimple world.
3473 Now we have to hunt them down ourselves. */
3474 walk_tree_without_duplicates (&data
.passed_type
,
3475 gimplify_parm_type
, &stmts
);
3477 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) != INTEGER_CST
)
3479 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3480 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3483 if (data
.passed_pointer
)
3485 tree type
= TREE_TYPE (data
.passed_type
);
3486 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3487 type
, data
.named_arg
))
3491 /* For constant-sized objects, this is trivial; for
3492 variable-sized objects, we have to play games. */
3493 if (TREE_CODE (DECL_SIZE_UNIT (parm
)) == INTEGER_CST
3494 && !(flag_stack_check
== GENERIC_STACK_CHECK
3495 && compare_tree_int (DECL_SIZE_UNIT (parm
),
3496 STACK_CHECK_MAX_VAR_SIZE
) > 0))
3498 local
= create_tmp_var (type
, get_name (parm
));
3499 DECL_IGNORED_P (local
) = 0;
3500 /* If PARM was addressable, move that flag over
3501 to the local copy, as its address will be taken,
3503 if (TREE_ADDRESSABLE (parm
))
3505 TREE_ADDRESSABLE (parm
) = 0;
3506 TREE_ADDRESSABLE (local
) = 1;
3511 tree ptr_type
, addr
;
3513 ptr_type
= build_pointer_type (type
);
3514 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3515 DECL_IGNORED_P (addr
) = 0;
3516 local
= build_fold_indirect_ref (addr
);
3518 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3519 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3520 t
= fold_convert (ptr_type
, t
);
3521 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3522 gimplify_and_add (t
, &stmts
);
3525 gimplify_assign (local
, parm
, &stmts
);
3527 SET_DECL_VALUE_EXPR (parm
, local
);
3528 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3533 VEC_free (tree
, heap
, fnargs
);
3538 /* Compute the size and offset from the start of the stacked arguments for a
3539 parm passed in mode PASSED_MODE and with type TYPE.
3541 INITIAL_OFFSET_PTR points to the current offset into the stacked
3544 The starting offset and size for this parm are returned in
3545 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3546 nonzero, the offset is that of stack slot, which is returned in
3547 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3548 padding required from the initial offset ptr to the stack slot.
3550 IN_REGS is nonzero if the argument will be passed in registers. It will
3551 never be set if REG_PARM_STACK_SPACE is not defined.
3553 FNDECL is the function in which the argument was defined.
3555 There are two types of rounding that are done. The first, controlled by
3556 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3557 list to be aligned to the specific boundary (in bits). This rounding
3558 affects the initial and starting offsets, but not the argument size.
3560 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3561 optionally rounds the size of the parm to PARM_BOUNDARY. The
3562 initial offset is not affected by this rounding, while the size always
3563 is and the starting offset may be. */
3565 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3566 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3567 callers pass in the total size of args so far as
3568 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3571 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3572 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3573 struct args_size
*initial_offset_ptr
,
3574 struct locate_and_pad_arg_data
*locate
)
3577 enum direction where_pad
;
3578 unsigned int boundary
;
3579 int reg_parm_stack_space
= 0;
3580 int part_size_in_regs
;
3582 #ifdef REG_PARM_STACK_SPACE
3583 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3585 /* If we have found a stack parm before we reach the end of the
3586 area reserved for registers, skip that area. */
3589 if (reg_parm_stack_space
> 0)
3591 if (initial_offset_ptr
->var
)
3593 initial_offset_ptr
->var
3594 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3595 ssize_int (reg_parm_stack_space
));
3596 initial_offset_ptr
->constant
= 0;
3598 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3599 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3602 #endif /* REG_PARM_STACK_SPACE */
3604 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3607 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3608 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3609 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3610 locate
->where_pad
= where_pad
;
3612 /* Alignment can't exceed MAX_SUPPORTED_STACK_ALIGNMENT. */
3613 if (boundary
> MAX_SUPPORTED_STACK_ALIGNMENT
)
3614 boundary
= MAX_SUPPORTED_STACK_ALIGNMENT
;
3616 locate
->boundary
= boundary
;
3618 if (SUPPORTS_STACK_ALIGNMENT
)
3620 /* stack_alignment_estimated can't change after stack has been
3622 if (crtl
->stack_alignment_estimated
< boundary
)
3624 if (!crtl
->stack_realign_processed
)
3625 crtl
->stack_alignment_estimated
= boundary
;
3628 /* If stack is realigned and stack alignment value
3629 hasn't been finalized, it is OK not to increase
3630 stack_alignment_estimated. The bigger alignment
3631 requirement is recorded in stack_alignment_needed
3633 gcc_assert (!crtl
->stack_realign_finalized
3634 && crtl
->stack_realign_needed
);
3639 /* Remember if the outgoing parameter requires extra alignment on the
3640 calling function side. */
3641 if (crtl
->stack_alignment_needed
< boundary
)
3642 crtl
->stack_alignment_needed
= boundary
;
3643 if (crtl
->preferred_stack_boundary
< boundary
)
3644 crtl
->preferred_stack_boundary
= boundary
;
3646 #ifdef ARGS_GROW_DOWNWARD
3647 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3648 if (initial_offset_ptr
->var
)
3649 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3650 initial_offset_ptr
->var
);
3654 if (where_pad
!= none
3655 && (!host_integerp (sizetree
, 1)
3656 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3657 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3658 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3661 locate
->slot_offset
.constant
+= part_size_in_regs
;
3664 #ifdef REG_PARM_STACK_SPACE
3665 || REG_PARM_STACK_SPACE (fndecl
) > 0
3668 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3669 &locate
->alignment_pad
);
3671 locate
->size
.constant
= (-initial_offset_ptr
->constant
3672 - locate
->slot_offset
.constant
);
3673 if (initial_offset_ptr
->var
)
3674 locate
->size
.var
= size_binop (MINUS_EXPR
,
3675 size_binop (MINUS_EXPR
,
3677 initial_offset_ptr
->var
),
3678 locate
->slot_offset
.var
);
3680 /* Pad_below needs the pre-rounded size to know how much to pad
3682 locate
->offset
= locate
->slot_offset
;
3683 if (where_pad
== downward
)
3684 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3686 #else /* !ARGS_GROW_DOWNWARD */
3688 #ifdef REG_PARM_STACK_SPACE
3689 || REG_PARM_STACK_SPACE (fndecl
) > 0
3692 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3693 &locate
->alignment_pad
);
3694 locate
->slot_offset
= *initial_offset_ptr
;
3696 #ifdef PUSH_ROUNDING
3697 if (passed_mode
!= BLKmode
)
3698 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3701 /* Pad_below needs the pre-rounded size to know how much to pad below
3702 so this must be done before rounding up. */
3703 locate
->offset
= locate
->slot_offset
;
3704 if (where_pad
== downward
)
3705 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3707 if (where_pad
!= none
3708 && (!host_integerp (sizetree
, 1)
3709 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3710 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3712 ADD_PARM_SIZE (locate
->size
, sizetree
);
3714 locate
->size
.constant
-= part_size_in_regs
;
3715 #endif /* ARGS_GROW_DOWNWARD */
3717 #ifdef FUNCTION_ARG_OFFSET
3718 locate
->offset
.constant
+= FUNCTION_ARG_OFFSET (passed_mode
, type
);
3722 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3723 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3726 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3727 struct args_size
*alignment_pad
)
3729 tree save_var
= NULL_TREE
;
3730 HOST_WIDE_INT save_constant
= 0;
3731 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3732 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3734 #ifdef SPARC_STACK_BOUNDARY_HACK
3735 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3736 the real alignment of %sp. However, when it does this, the
3737 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3738 if (SPARC_STACK_BOUNDARY_HACK
)
3742 if (boundary
> PARM_BOUNDARY
)
3744 save_var
= offset_ptr
->var
;
3745 save_constant
= offset_ptr
->constant
;
3748 alignment_pad
->var
= NULL_TREE
;
3749 alignment_pad
->constant
= 0;
3751 if (boundary
> BITS_PER_UNIT
)
3753 if (offset_ptr
->var
)
3755 tree sp_offset_tree
= ssize_int (sp_offset
);
3756 tree offset
= size_binop (PLUS_EXPR
,
3757 ARGS_SIZE_TREE (*offset_ptr
),
3759 #ifdef ARGS_GROW_DOWNWARD
3760 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3762 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3765 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3766 /* ARGS_SIZE_TREE includes constant term. */
3767 offset_ptr
->constant
= 0;
3768 if (boundary
> PARM_BOUNDARY
)
3769 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3774 offset_ptr
->constant
= -sp_offset
+
3775 #ifdef ARGS_GROW_DOWNWARD
3776 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3778 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3780 if (boundary
> PARM_BOUNDARY
)
3781 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3787 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3789 if (passed_mode
!= BLKmode
)
3791 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3792 offset_ptr
->constant
3793 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3794 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3795 - GET_MODE_SIZE (passed_mode
));
3799 if (TREE_CODE (sizetree
) != INTEGER_CST
3800 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3802 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3803 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3805 ADD_PARM_SIZE (*offset_ptr
, s2
);
3806 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3812 /* True if register REGNO was alive at a place where `setjmp' was
3813 called and was set more than once or is an argument. Such regs may
3814 be clobbered by `longjmp'. */
3817 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3819 /* There appear to be cases where some local vars never reach the
3820 backend but have bogus regnos. */
3821 if (regno
>= max_reg_num ())
3824 return ((REG_N_SETS (regno
) > 1
3825 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3826 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3829 /* Walk the tree of blocks describing the binding levels within a
3830 function and warn about variables the might be killed by setjmp or
3831 vfork. This is done after calling flow_analysis before register
3832 allocation since that will clobber the pseudo-regs to hard
3836 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3840 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3842 if (TREE_CODE (decl
) == VAR_DECL
3843 && DECL_RTL_SET_P (decl
)
3844 && REG_P (DECL_RTL (decl
))
3845 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3846 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3847 " %<longjmp%> or %<vfork%>", decl
);
3850 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3851 setjmp_vars_warning (setjmp_crosses
, sub
);
3854 /* Do the appropriate part of setjmp_vars_warning
3855 but for arguments instead of local variables. */
3858 setjmp_args_warning (bitmap setjmp_crosses
)
3861 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3862 decl
; decl
= TREE_CHAIN (decl
))
3863 if (DECL_RTL (decl
) != 0
3864 && REG_P (DECL_RTL (decl
))
3865 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3866 warning (OPT_Wclobbered
,
3867 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3871 /* Generate warning messages for variables live across setjmp. */
3874 generate_setjmp_warnings (void)
3876 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3878 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3879 || bitmap_empty_p (setjmp_crosses
))
3882 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3883 setjmp_args_warning (setjmp_crosses
);
3887 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3888 and create duplicate blocks. */
3889 /* ??? Need an option to either create block fragments or to create
3890 abstract origin duplicates of a source block. It really depends
3891 on what optimization has been performed. */
3894 reorder_blocks (void)
3896 tree block
= DECL_INITIAL (current_function_decl
);
3897 VEC(tree
,heap
) *block_stack
;
3899 if (block
== NULL_TREE
)
3902 block_stack
= VEC_alloc (tree
, heap
, 10);
3904 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3905 clear_block_marks (block
);
3907 /* Prune the old trees away, so that they don't get in the way. */
3908 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3909 BLOCK_CHAIN (block
) = NULL_TREE
;
3911 /* Recreate the block tree from the note nesting. */
3912 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3913 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3915 VEC_free (tree
, heap
, block_stack
);
3918 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3921 clear_block_marks (tree block
)
3925 TREE_ASM_WRITTEN (block
) = 0;
3926 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3927 block
= BLOCK_CHAIN (block
);
3932 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3936 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3940 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3942 tree block
= NOTE_BLOCK (insn
);
3945 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3946 ? BLOCK_FRAGMENT_ORIGIN (block
)
3949 /* If we have seen this block before, that means it now
3950 spans multiple address regions. Create a new fragment. */
3951 if (TREE_ASM_WRITTEN (block
))
3953 tree new_block
= copy_node (block
);
3955 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3956 BLOCK_FRAGMENT_CHAIN (new_block
)
3957 = BLOCK_FRAGMENT_CHAIN (origin
);
3958 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3960 NOTE_BLOCK (insn
) = new_block
;
3964 BLOCK_SUBBLOCKS (block
) = 0;
3965 TREE_ASM_WRITTEN (block
) = 1;
3966 /* When there's only one block for the entire function,
3967 current_block == block and we mustn't do this, it
3968 will cause infinite recursion. */
3969 if (block
!= current_block
)
3971 if (block
!= origin
)
3972 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3974 BLOCK_SUPERCONTEXT (block
) = current_block
;
3975 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3976 BLOCK_SUBBLOCKS (current_block
) = block
;
3977 current_block
= origin
;
3979 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3981 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3983 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3984 BLOCK_SUBBLOCKS (current_block
)
3985 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3986 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3992 /* Reverse the order of elements in the chain T of blocks,
3993 and return the new head of the chain (old last element). */
3996 blocks_nreverse (tree t
)
3998 tree prev
= 0, decl
, next
;
3999 for (decl
= t
; decl
; decl
= next
)
4001 next
= BLOCK_CHAIN (decl
);
4002 BLOCK_CHAIN (decl
) = prev
;
4008 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
4009 non-NULL, list them all into VECTOR, in a depth-first preorder
4010 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
4014 all_blocks (tree block
, tree
*vector
)
4020 TREE_ASM_WRITTEN (block
) = 0;
4022 /* Record this block. */
4024 vector
[n_blocks
] = block
;
4028 /* Record the subblocks, and their subblocks... */
4029 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
4030 vector
? vector
+ n_blocks
: 0);
4031 block
= BLOCK_CHAIN (block
);
4037 /* Return a vector containing all the blocks rooted at BLOCK. The
4038 number of elements in the vector is stored in N_BLOCKS_P. The
4039 vector is dynamically allocated; it is the caller's responsibility
4040 to call `free' on the pointer returned. */
4043 get_block_vector (tree block
, int *n_blocks_p
)
4047 *n_blocks_p
= all_blocks (block
, NULL
);
4048 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
4049 all_blocks (block
, block_vector
);
4051 return block_vector
;
4054 static GTY(()) int next_block_index
= 2;
4056 /* Set BLOCK_NUMBER for all the blocks in FN. */
4059 number_blocks (tree fn
)
4065 /* For SDB and XCOFF debugging output, we start numbering the blocks
4066 from 1 within each function, rather than keeping a running
4068 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
4069 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
4070 next_block_index
= 1;
4073 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
4075 /* The top-level BLOCK isn't numbered at all. */
4076 for (i
= 1; i
< n_blocks
; ++i
)
4077 /* We number the blocks from two. */
4078 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
4080 free (block_vector
);
4085 /* If VAR is present in a subblock of BLOCK, return the subblock. */
4088 debug_find_var_in_block_tree (tree var
, tree block
)
4092 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
4096 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
4098 tree ret
= debug_find_var_in_block_tree (var
, t
);
4106 /* Keep track of whether we're in a dummy function context. If we are,
4107 we don't want to invoke the set_current_function hook, because we'll
4108 get into trouble if the hook calls target_reinit () recursively or
4109 when the initial initialization is not yet complete. */
4111 static bool in_dummy_function
;
4113 /* Invoke the target hook when setting cfun. Update the optimization options
4114 if the function uses different options than the default. */
4117 invoke_set_current_function_hook (tree fndecl
)
4119 if (!in_dummy_function
)
4121 tree opts
= ((fndecl
)
4122 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
4123 : optimization_default_node
);
4126 opts
= optimization_default_node
;
4128 /* Change optimization options if needed. */
4129 if (optimization_current_node
!= opts
)
4131 optimization_current_node
= opts
;
4132 cl_optimization_restore (TREE_OPTIMIZATION (opts
));
4135 targetm
.set_current_function (fndecl
);
4139 /* cfun should never be set directly; use this function. */
4142 set_cfun (struct function
*new_cfun
)
4144 if (cfun
!= new_cfun
)
4147 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
4151 /* Initialized with NOGC, making this poisonous to the garbage collector. */
4153 static VEC(function_p
,heap
) *cfun_stack
;
4155 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
4158 push_cfun (struct function
*new_cfun
)
4160 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4161 set_cfun (new_cfun
);
4164 /* Pop cfun from the stack. */
4169 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
4170 set_cfun (new_cfun
);
4173 /* Return value of funcdef and increase it. */
4175 get_next_funcdef_no (void)
4177 return funcdef_no
++;
4180 /* Allocate a function structure for FNDECL and set its contents
4181 to the defaults. Set cfun to the newly-allocated object.
4182 Some of the helper functions invoked during initialization assume
4183 that cfun has already been set. Therefore, assign the new object
4184 directly into cfun and invoke the back end hook explicitly at the
4185 very end, rather than initializing a temporary and calling set_cfun
4188 ABSTRACT_P is true if this is a function that will never be seen by
4189 the middle-end. Such functions are front-end concepts (like C++
4190 function templates) that do not correspond directly to functions
4191 placed in object files. */
4194 allocate_struct_function (tree fndecl
, bool abstract_p
)
4197 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
4199 cfun
= ggc_alloc_cleared_function ();
4201 init_eh_for_function ();
4203 if (init_machine_status
)
4204 cfun
->machine
= (*init_machine_status
) ();
4206 #ifdef OVERRIDE_ABI_FORMAT
4207 OVERRIDE_ABI_FORMAT (fndecl
);
4210 invoke_set_current_function_hook (fndecl
);
4212 if (fndecl
!= NULL_TREE
)
4214 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
4215 cfun
->decl
= fndecl
;
4216 current_function_funcdef_no
= get_next_funcdef_no ();
4218 result
= DECL_RESULT (fndecl
);
4219 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
4221 #ifdef PCC_STATIC_STRUCT_RETURN
4222 cfun
->returns_pcc_struct
= 1;
4224 cfun
->returns_struct
= 1;
4229 && TYPE_ARG_TYPES (fntype
) != 0
4230 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
4231 != void_type_node
));
4233 /* Assume all registers in stdarg functions need to be saved. */
4234 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
4235 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
4237 /* ??? This could be set on a per-function basis by the front-end
4238 but is this worth the hassle? */
4239 cfun
->can_throw_non_call_exceptions
= flag_non_call_exceptions
;
4243 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
4244 instead of just setting it. */
4247 push_struct_function (tree fndecl
)
4249 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
4250 allocate_struct_function (fndecl
, false);
4253 /* Reset crtl and other non-struct-function variables to defaults as
4254 appropriate for emitting rtl at the start of a function. */
4257 prepare_function_start (void)
4259 gcc_assert (!crtl
->emit
.x_last_insn
);
4262 init_varasm_status ();
4264 default_rtl_profile ();
4266 cse_not_expected
= ! optimize
;
4268 /* Caller save not needed yet. */
4269 caller_save_needed
= 0;
4271 /* We haven't done register allocation yet. */
4274 /* Indicate that we have not instantiated virtual registers yet. */
4275 virtuals_instantiated
= 0;
4277 /* Indicate that we want CONCATs now. */
4278 generating_concat_p
= 1;
4280 /* Indicate we have no need of a frame pointer yet. */
4281 frame_pointer_needed
= 0;
4284 /* Initialize the rtl expansion mechanism so that we can do simple things
4285 like generate sequences. This is used to provide a context during global
4286 initialization of some passes. You must call expand_dummy_function_end
4287 to exit this context. */
4290 init_dummy_function_start (void)
4292 gcc_assert (!in_dummy_function
);
4293 in_dummy_function
= true;
4294 push_struct_function (NULL_TREE
);
4295 prepare_function_start ();
4298 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
4299 and initialize static variables for generating RTL for the statements
4303 init_function_start (tree subr
)
4305 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
4306 set_cfun (DECL_STRUCT_FUNCTION (subr
));
4308 allocate_struct_function (subr
, false);
4309 prepare_function_start ();
4311 /* Warn if this value is an aggregate type,
4312 regardless of which calling convention we are using for it. */
4313 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
4314 warning (OPT_Waggregate_return
, "function returns an aggregate");
4317 /* Make sure all values used by the optimization passes have sane defaults. */
4319 init_function_for_compilation (void)
4325 struct rtl_opt_pass pass_init_function
=
4329 "*init_function", /* name */
4331 init_function_for_compilation
, /* execute */
4334 0, /* static_pass_number */
4335 TV_NONE
, /* tv_id */
4336 0, /* properties_required */
4337 0, /* properties_provided */
4338 0, /* properties_destroyed */
4339 0, /* todo_flags_start */
4340 0 /* todo_flags_finish */
4346 expand_main_function (void)
4348 #if (defined(INVOKE__main) \
4349 || (!defined(HAS_INIT_SECTION) \
4350 && !defined(INIT_SECTION_ASM_OP) \
4351 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
4352 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
4356 /* Expand code to initialize the stack_protect_guard. This is invoked at
4357 the beginning of a function to be protected. */
4359 #ifndef HAVE_stack_protect_set
4360 # define HAVE_stack_protect_set 0
4361 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
4365 stack_protect_prologue (void)
4367 tree guard_decl
= targetm
.stack_protect_guard ();
4370 x
= expand_normal (crtl
->stack_protect_guard
);
4371 y
= expand_normal (guard_decl
);
4373 /* Allow the target to copy from Y to X without leaking Y into a
4375 if (HAVE_stack_protect_set
)
4377 rtx insn
= gen_stack_protect_set (x
, y
);
4385 /* Otherwise do a straight move. */
4386 emit_move_insn (x
, y
);
4389 /* Expand code to verify the stack_protect_guard. This is invoked at
4390 the end of a function to be protected. */
4392 #ifndef HAVE_stack_protect_test
4393 # define HAVE_stack_protect_test 0
4394 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4398 stack_protect_epilogue (void)
4400 tree guard_decl
= targetm
.stack_protect_guard ();
4401 rtx label
= gen_label_rtx ();
4404 x
= expand_normal (crtl
->stack_protect_guard
);
4405 y
= expand_normal (guard_decl
);
4407 /* Allow the target to compare Y with X without leaking either into
4409 switch (HAVE_stack_protect_test
!= 0)
4412 tmp
= gen_stack_protect_test (x
, y
, label
);
4421 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4425 /* The noreturn predictor has been moved to the tree level. The rtl-level
4426 predictors estimate this branch about 20%, which isn't enough to get
4427 things moved out of line. Since this is the only extant case of adding
4428 a noreturn function at the rtl level, it doesn't seem worth doing ought
4429 except adding the prediction by hand. */
4430 tmp
= get_last_insn ();
4432 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4434 expand_expr_stmt (targetm
.stack_protect_fail ());
4438 /* Start the RTL for a new function, and set variables used for
4440 SUBR is the FUNCTION_DECL node.
4441 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4442 the function's parameters, which must be run at any return statement. */
4445 expand_function_start (tree subr
)
4447 /* Make sure volatile mem refs aren't considered
4448 valid operands of arithmetic insns. */
4449 init_recog_no_volatile ();
4453 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4456 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4458 /* Make the label for return statements to jump to. Do not special
4459 case machines with special return instructions -- they will be
4460 handled later during jump, ifcvt, or epilogue creation. */
4461 return_label
= gen_label_rtx ();
4463 /* Initialize rtx used to return the value. */
4464 /* Do this before assign_parms so that we copy the struct value address
4465 before any library calls that assign parms might generate. */
4467 /* Decide whether to return the value in memory or in a register. */
4468 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4470 /* Returning something that won't go in a register. */
4471 rtx value_address
= 0;
4473 #ifdef PCC_STATIC_STRUCT_RETURN
4474 if (cfun
->returns_pcc_struct
)
4476 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4477 value_address
= assemble_static_space (size
);
4482 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4483 /* Expect to be passed the address of a place to store the value.
4484 If it is passed as an argument, assign_parms will take care of
4488 value_address
= gen_reg_rtx (Pmode
);
4489 emit_move_insn (value_address
, sv
);
4494 rtx x
= value_address
;
4495 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4497 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4498 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4500 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4503 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4504 /* If return mode is void, this decl rtl should not be used. */
4505 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4508 /* Compute the return values into a pseudo reg, which we will copy
4509 into the true return register after the cleanups are done. */
4510 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4511 if (TYPE_MODE (return_type
) != BLKmode
4512 && targetm
.calls
.return_in_msb (return_type
))
4513 /* expand_function_end will insert the appropriate padding in
4514 this case. Use the return value's natural (unpadded) mode
4515 within the function proper. */
4516 SET_DECL_RTL (DECL_RESULT (subr
),
4517 gen_reg_rtx (TYPE_MODE (return_type
)));
4520 /* In order to figure out what mode to use for the pseudo, we
4521 figure out what the mode of the eventual return register will
4522 actually be, and use that. */
4523 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4525 /* Structures that are returned in registers are not
4526 aggregate_value_p, so we may see a PARALLEL or a REG. */
4527 if (REG_P (hard_reg
))
4528 SET_DECL_RTL (DECL_RESULT (subr
),
4529 gen_reg_rtx (GET_MODE (hard_reg
)));
4532 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4533 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4537 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4538 result to the real return register(s). */
4539 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4542 /* Initialize rtx for parameters and local variables.
4543 In some cases this requires emitting insns. */
4544 assign_parms (subr
);
4546 /* If function gets a static chain arg, store it. */
4547 if (cfun
->static_chain_decl
)
4549 tree parm
= cfun
->static_chain_decl
;
4550 rtx local
, chain
, insn
;
4552 local
= gen_reg_rtx (Pmode
);
4553 chain
= targetm
.calls
.static_chain (current_function_decl
, true);
4555 set_decl_incoming_rtl (parm
, chain
, false);
4556 SET_DECL_RTL (parm
, local
);
4557 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4559 insn
= emit_move_insn (local
, chain
);
4561 /* Mark the register as eliminable, similar to parameters. */
4563 && reg_mentioned_p (arg_pointer_rtx
, XEXP (chain
, 0)))
4564 set_unique_reg_note (insn
, REG_EQUIV
, chain
);
4567 /* If the function receives a non-local goto, then store the
4568 bits we need to restore the frame pointer. */
4569 if (cfun
->nonlocal_goto_save_area
)
4574 /* ??? We need to do this save early. Unfortunately here is
4575 before the frame variable gets declared. Help out... */
4576 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4577 if (!DECL_RTL_SET_P (var
))
4580 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4581 cfun
->nonlocal_goto_save_area
,
4582 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4583 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4584 r_save
= convert_memory_address (Pmode
, r_save
);
4586 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4587 update_nonlocal_goto_save_area ();
4590 /* The following was moved from init_function_start.
4591 The move is supposed to make sdb output more accurate. */
4592 /* Indicate the beginning of the function body,
4593 as opposed to parm setup. */
4594 emit_note (NOTE_INSN_FUNCTION_BEG
);
4596 gcc_assert (NOTE_P (get_last_insn ()));
4598 parm_birth_insn
= get_last_insn ();
4603 PROFILE_HOOK (current_function_funcdef_no
);
4607 /* After the display initializations is where the stack checking
4609 if(flag_stack_check
)
4610 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4612 /* Make sure there is a line number after the function entry setup code. */
4613 force_next_line_note ();
4616 /* Undo the effects of init_dummy_function_start. */
4618 expand_dummy_function_end (void)
4620 gcc_assert (in_dummy_function
);
4622 /* End any sequences that failed to be closed due to syntax errors. */
4623 while (in_sequence_p ())
4626 /* Outside function body, can't compute type's actual size
4627 until next function's body starts. */
4629 free_after_parsing (cfun
);
4630 free_after_compilation (cfun
);
4632 in_dummy_function
= false;
4635 /* Call DOIT for each hard register used as a return value from
4636 the current function. */
4639 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4641 rtx outgoing
= crtl
->return_rtx
;
4646 if (REG_P (outgoing
))
4647 (*doit
) (outgoing
, arg
);
4648 else if (GET_CODE (outgoing
) == PARALLEL
)
4652 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4654 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4656 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4663 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4669 clobber_return_register (void)
4671 diddle_return_value (do_clobber_return_reg
, NULL
);
4673 /* In case we do use pseudo to return value, clobber it too. */
4674 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4676 tree decl_result
= DECL_RESULT (current_function_decl
);
4677 rtx decl_rtl
= DECL_RTL (decl_result
);
4678 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4680 do_clobber_return_reg (decl_rtl
, NULL
);
4686 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4692 use_return_register (void)
4694 diddle_return_value (do_use_return_reg
, NULL
);
4697 /* Possibly warn about unused parameters. */
4699 do_warn_unused_parameter (tree fn
)
4703 for (decl
= DECL_ARGUMENTS (fn
);
4704 decl
; decl
= TREE_CHAIN (decl
))
4705 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4706 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4707 && !TREE_NO_WARNING (decl
))
4708 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4711 static GTY(()) rtx initial_trampoline
;
4713 /* Generate RTL for the end of the current function. */
4716 expand_function_end (void)
4720 /* If arg_pointer_save_area was referenced only from a nested
4721 function, we will not have initialized it yet. Do that now. */
4722 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4723 get_arg_pointer_save_area ();
4725 /* If we are doing generic stack checking and this function makes calls,
4726 do a stack probe at the start of the function to ensure we have enough
4727 space for another stack frame. */
4728 if (flag_stack_check
== GENERIC_STACK_CHECK
)
4732 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4735 rtx max_frame_size
= GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
);
4737 if (STACK_CHECK_MOVING_SP
)
4738 anti_adjust_stack_and_probe (max_frame_size
, true);
4740 probe_stack_range (STACK_OLD_CHECK_PROTECT
, max_frame_size
);
4743 emit_insn_before (seq
, stack_check_probe_note
);
4748 /* End any sequences that failed to be closed due to syntax errors. */
4749 while (in_sequence_p ())
4752 clear_pending_stack_adjust ();
4753 do_pending_stack_adjust ();
4755 /* Output a linenumber for the end of the function.
4756 SDB depends on this. */
4757 force_next_line_note ();
4758 set_curr_insn_source_location (input_location
);
4760 /* Before the return label (if any), clobber the return
4761 registers so that they are not propagated live to the rest of
4762 the function. This can only happen with functions that drop
4763 through; if there had been a return statement, there would
4764 have either been a return rtx, or a jump to the return label.
4766 We delay actual code generation after the current_function_value_rtx
4768 clobber_after
= get_last_insn ();
4770 /* Output the label for the actual return from the function. */
4771 emit_label (return_label
);
4773 if (USING_SJLJ_EXCEPTIONS
)
4775 /* Let except.c know where it should emit the call to unregister
4776 the function context for sjlj exceptions. */
4777 if (flag_exceptions
)
4778 sjlj_emit_function_exit_after (get_last_insn ());
4782 /* We want to ensure that instructions that may trap are not
4783 moved into the epilogue by scheduling, because we don't
4784 always emit unwind information for the epilogue. */
4785 if (cfun
->can_throw_non_call_exceptions
)
4786 emit_insn (gen_blockage ());
4789 /* If this is an implementation of throw, do what's necessary to
4790 communicate between __builtin_eh_return and the epilogue. */
4791 expand_eh_return ();
4793 /* If scalar return value was computed in a pseudo-reg, or was a named
4794 return value that got dumped to the stack, copy that to the hard
4796 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4798 tree decl_result
= DECL_RESULT (current_function_decl
);
4799 rtx decl_rtl
= DECL_RTL (decl_result
);
4801 if (REG_P (decl_rtl
)
4802 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4803 : DECL_REGISTER (decl_result
))
4805 rtx real_decl_rtl
= crtl
->return_rtx
;
4807 /* This should be set in assign_parms. */
4808 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4810 /* If this is a BLKmode structure being returned in registers,
4811 then use the mode computed in expand_return. Note that if
4812 decl_rtl is memory, then its mode may have been changed,
4813 but that crtl->return_rtx has not. */
4814 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4815 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4817 /* If a non-BLKmode return value should be padded at the least
4818 significant end of the register, shift it left by the appropriate
4819 amount. BLKmode results are handled using the group load/store
4821 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4822 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4824 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4825 REGNO (real_decl_rtl
)),
4827 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4829 /* If a named return value dumped decl_return to memory, then
4830 we may need to re-do the PROMOTE_MODE signed/unsigned
4832 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4834 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4835 promote_function_mode (TREE_TYPE (decl_result
),
4836 GET_MODE (decl_rtl
), &unsignedp
,
4837 TREE_TYPE (current_function_decl
), 1);
4839 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4841 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4843 /* If expand_function_start has created a PARALLEL for decl_rtl,
4844 move the result to the real return registers. Otherwise, do
4845 a group load from decl_rtl for a named return. */
4846 if (GET_CODE (decl_rtl
) == PARALLEL
)
4847 emit_group_move (real_decl_rtl
, decl_rtl
);
4849 emit_group_load (real_decl_rtl
, decl_rtl
,
4850 TREE_TYPE (decl_result
),
4851 int_size_in_bytes (TREE_TYPE (decl_result
)));
4853 /* In the case of complex integer modes smaller than a word, we'll
4854 need to generate some non-trivial bitfield insertions. Do that
4855 on a pseudo and not the hard register. */
4856 else if (GET_CODE (decl_rtl
) == CONCAT
4857 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4858 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4860 int old_generating_concat_p
;
4863 old_generating_concat_p
= generating_concat_p
;
4864 generating_concat_p
= 0;
4865 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4866 generating_concat_p
= old_generating_concat_p
;
4868 emit_move_insn (tmp
, decl_rtl
);
4869 emit_move_insn (real_decl_rtl
, tmp
);
4872 emit_move_insn (real_decl_rtl
, decl_rtl
);
4876 /* If returning a structure, arrange to return the address of the value
4877 in a place where debuggers expect to find it.
4879 If returning a structure PCC style,
4880 the caller also depends on this value.
4881 And cfun->returns_pcc_struct is not necessarily set. */
4882 if (cfun
->returns_struct
4883 || cfun
->returns_pcc_struct
)
4885 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4886 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4889 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4890 type
= TREE_TYPE (type
);
4892 value_address
= XEXP (value_address
, 0);
4894 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4895 current_function_decl
, true);
4897 /* Mark this as a function return value so integrate will delete the
4898 assignment and USE below when inlining this function. */
4899 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4901 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4902 value_address
= convert_memory_address (GET_MODE (outgoing
),
4905 emit_move_insn (outgoing
, value_address
);
4907 /* Show return register used to hold result (in this case the address
4909 crtl
->return_rtx
= outgoing
;
4912 /* Emit the actual code to clobber return register. */
4917 clobber_return_register ();
4921 emit_insn_after (seq
, clobber_after
);
4924 /* Output the label for the naked return from the function. */
4925 if (naked_return_label
)
4926 emit_label (naked_return_label
);
4928 /* @@@ This is a kludge. We want to ensure that instructions that
4929 may trap are not moved into the epilogue by scheduling, because
4930 we don't always emit unwind information for the epilogue. */
4931 if (!USING_SJLJ_EXCEPTIONS
&& cfun
->can_throw_non_call_exceptions
)
4932 emit_insn (gen_blockage ());
4934 /* If stack protection is enabled for this function, check the guard. */
4935 if (crtl
->stack_protect_guard
)
4936 stack_protect_epilogue ();
4938 /* If we had calls to alloca, and this machine needs
4939 an accurate stack pointer to exit the function,
4940 insert some code to save and restore the stack pointer. */
4941 if (! EXIT_IGNORE_STACK
4942 && cfun
->calls_alloca
)
4946 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4947 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4950 /* ??? This should no longer be necessary since stupid is no longer with
4951 us, but there are some parts of the compiler (eg reload_combine, and
4952 sh mach_dep_reorg) that still try and compute their own lifetime info
4953 instead of using the general framework. */
4954 use_return_register ();
4958 get_arg_pointer_save_area (void)
4960 rtx ret
= arg_pointer_save_area
;
4964 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4965 arg_pointer_save_area
= ret
;
4968 if (! crtl
->arg_pointer_save_area_init
)
4972 /* Save the arg pointer at the beginning of the function. The
4973 generated stack slot may not be a valid memory address, so we
4974 have to check it and fix it if necessary. */
4976 emit_move_insn (validize_mem (ret
),
4977 crtl
->args
.internal_arg_pointer
);
4981 push_topmost_sequence ();
4982 emit_insn_after (seq
, entry_of_function ());
4983 pop_topmost_sequence ();
4989 /* Add a list of INSNS to the hash HASHP, possibly allocating HASHP
4990 for the first time. */
4993 record_insns (rtx insns
, rtx end
, htab_t
*hashp
)
4996 htab_t hash
= *hashp
;
5000 = htab_create_ggc (17, htab_hash_pointer
, htab_eq_pointer
, NULL
);
5002 for (tmp
= insns
; tmp
!= end
; tmp
= NEXT_INSN (tmp
))
5004 void **slot
= htab_find_slot (hash
, tmp
, INSERT
);
5005 gcc_assert (*slot
== NULL
);
5010 /* INSN has been duplicated as COPY, as part of duping a basic block.
5011 If INSN is an epilogue insn, then record COPY as epilogue as well. */
5014 maybe_copy_epilogue_insn (rtx insn
, rtx copy
)
5018 if (epilogue_insn_hash
== NULL
5019 || htab_find (epilogue_insn_hash
, insn
) == NULL
)
5022 slot
= htab_find_slot (epilogue_insn_hash
, copy
, INSERT
);
5023 gcc_assert (*slot
== NULL
);
5027 /* Set the locator of the insn chain starting at INSN to LOC. */
5029 set_insn_locators (rtx insn
, int loc
)
5031 while (insn
!= NULL_RTX
)
5034 INSN_LOCATOR (insn
) = loc
;
5035 insn
= NEXT_INSN (insn
);
5039 /* Determine if any INSNs in HASH are, or are part of, INSN. Because
5040 we can be running after reorg, SEQUENCE rtl is possible. */
5043 contains (const_rtx insn
, htab_t hash
)
5048 if (NONJUMP_INSN_P (insn
) && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
5051 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
5052 if (htab_find (hash
, XVECEXP (PATTERN (insn
), 0, i
)))
5057 return htab_find (hash
, insn
) != NULL
;
5061 prologue_epilogue_contains (const_rtx insn
)
5063 if (contains (insn
, prologue_insn_hash
))
5065 if (contains (insn
, epilogue_insn_hash
))
5071 /* Insert gen_return at the end of block BB. This also means updating
5072 block_for_insn appropriately. */
5075 emit_return_into_block (basic_block bb
)
5077 emit_jump_insn_after (gen_return (), BB_END (bb
));
5079 #endif /* HAVE_return */
5081 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
5082 this into place with notes indicating where the prologue ends and where
5083 the epilogue begins. Update the basic block information when possible. */
5086 thread_prologue_and_epilogue_insns (void)
5090 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
5093 #if defined (HAVE_epilogue) || defined(HAVE_return)
5094 rtx epilogue_end
= NULL_RTX
;
5098 rtl_profile_for_bb (ENTRY_BLOCK_PTR
);
5099 #ifdef HAVE_prologue
5103 seq
= gen_prologue ();
5106 /* Insert an explicit USE for the frame pointer
5107 if the profiling is on and the frame pointer is required. */
5108 if (crtl
->profile
&& frame_pointer_needed
)
5109 emit_use (hard_frame_pointer_rtx
);
5111 /* Retain a map of the prologue insns. */
5112 record_insns (seq
, NULL
, &prologue_insn_hash
);
5113 emit_note (NOTE_INSN_PROLOGUE_END
);
5115 #ifndef PROFILE_BEFORE_PROLOGUE
5116 /* Ensure that instructions are not moved into the prologue when
5117 profiling is on. The call to the profiling routine can be
5118 emitted within the live range of a call-clobbered register. */
5120 emit_insn (gen_blockage ());
5125 set_insn_locators (seq
, prologue_locator
);
5127 /* Can't deal with multiple successors of the entry block
5128 at the moment. Function should always have at least one
5130 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
5132 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
5137 /* If the exit block has no non-fake predecessors, we don't need
5139 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5140 if ((e
->flags
& EDGE_FAKE
) == 0)
5145 rtl_profile_for_bb (EXIT_BLOCK_PTR
);
5147 if (optimize
&& HAVE_return
)
5149 /* If we're allowed to generate a simple return instruction,
5150 then by definition we don't need a full epilogue. Examine
5151 the block that falls through to EXIT. If it does not
5152 contain any code, examine its predecessors and try to
5153 emit (conditional) return instructions. */
5158 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5159 if (e
->flags
& EDGE_FALLTHRU
)
5165 /* Verify that there are no active instructions in the last block. */
5166 label
= BB_END (last
);
5167 while (label
&& !LABEL_P (label
))
5169 if (active_insn_p (label
))
5171 label
= PREV_INSN (label
);
5174 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
5178 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
5180 basic_block bb
= e
->src
;
5183 if (bb
== ENTRY_BLOCK_PTR
)
5190 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
5196 /* If we have an unconditional jump, we can replace that
5197 with a simple return instruction. */
5198 if (simplejump_p (jump
))
5200 emit_return_into_block (bb
);
5204 /* If we have a conditional jump, we can try to replace
5205 that with a conditional return instruction. */
5206 else if (condjump_p (jump
))
5208 if (! redirect_jump (jump
, 0, 0))
5214 /* If this block has only one successor, it both jumps
5215 and falls through to the fallthru block, so we can't
5217 if (single_succ_p (bb
))
5229 /* Fix up the CFG for the successful change we just made. */
5230 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
5233 /* Emit a return insn for the exit fallthru block. Whether
5234 this is still reachable will be determined later. */
5236 emit_barrier_after (BB_END (last
));
5237 emit_return_into_block (last
);
5238 epilogue_end
= BB_END (last
);
5239 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
5245 /* A small fib -- epilogue is not yet completed, but we wish to re-use
5246 this marker for the splits of EH_RETURN patterns, and nothing else
5247 uses the flag in the meantime. */
5248 epilogue_completed
= 1;
5250 #ifdef HAVE_eh_return
5251 /* Find non-fallthru edges that end with EH_RETURN instructions. On
5252 some targets, these get split to a special version of the epilogue
5253 code. In order to be able to properly annotate these with unwind
5254 info, try to split them now. If we get a valid split, drop an
5255 EPILOGUE_BEG note and mark the insns as epilogue insns. */
5256 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5258 rtx prev
, last
, trial
;
5260 if (e
->flags
& EDGE_FALLTHRU
)
5262 last
= BB_END (e
->src
);
5263 if (!eh_returnjump_p (last
))
5266 prev
= PREV_INSN (last
);
5267 trial
= try_split (PATTERN (last
), last
, 1);
5271 record_insns (NEXT_INSN (prev
), NEXT_INSN (trial
), &epilogue_insn_hash
);
5272 emit_note_after (NOTE_INSN_EPILOGUE_BEG
, prev
);
5276 /* Find the edge that falls through to EXIT. Other edges may exist
5277 due to RETURN instructions, but those don't need epilogues.
5278 There really shouldn't be a mixture -- either all should have
5279 been converted or none, however... */
5281 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5282 if (e
->flags
& EDGE_FALLTHRU
)
5287 #ifdef HAVE_epilogue
5291 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
5292 seq
= gen_epilogue ();
5293 emit_jump_insn (seq
);
5295 /* Retain a map of the epilogue insns. */
5296 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5297 set_insn_locators (seq
, epilogue_locator
);
5302 insert_insn_on_edge (seq
, e
);
5310 if (! next_active_insn (BB_END (e
->src
)))
5312 /* We have a fall-through edge to the exit block, the source is not
5313 at the end of the function, and there will be an assembler epilogue
5314 at the end of the function.
5315 We can't use force_nonfallthru here, because that would try to
5316 use return. Inserting a jump 'by hand' is extremely messy, so
5317 we take advantage of cfg_layout_finalize using
5318 fixup_fallthru_exit_predecessor. */
5319 cfg_layout_initialize (0);
5320 FOR_EACH_BB (cur_bb
)
5321 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
5322 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
5323 cur_bb
->aux
= cur_bb
->next_bb
;
5324 cfg_layout_finalize ();
5327 default_rtl_profile ();
5331 commit_edge_insertions ();
5333 /* The epilogue insns we inserted may cause the exit edge to no longer
5335 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5337 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
5338 && returnjump_p (BB_END (e
->src
)))
5339 e
->flags
&= ~EDGE_FALLTHRU
;
5343 #ifdef HAVE_sibcall_epilogue
5344 /* Emit sibling epilogues before any sibling call sites. */
5345 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
5347 basic_block bb
= e
->src
;
5348 rtx insn
= BB_END (bb
);
5351 || ! SIBLING_CALL_P (insn
))
5358 emit_note (NOTE_INSN_EPILOGUE_BEG
);
5359 emit_insn (gen_sibcall_epilogue ());
5363 /* Retain a map of the epilogue insns. Used in life analysis to
5364 avoid getting rid of sibcall epilogue insns. Do this before we
5365 actually emit the sequence. */
5366 record_insns (seq
, NULL
, &epilogue_insn_hash
);
5367 set_insn_locators (seq
, epilogue_locator
);
5369 emit_insn_before (seq
, insn
);
5374 #ifdef HAVE_epilogue
5379 /* Similarly, move any line notes that appear after the epilogue.
5380 There is no need, however, to be quite so anal about the existence
5381 of such a note. Also possibly move
5382 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
5384 for (insn
= epilogue_end
; insn
; insn
= next
)
5386 next
= NEXT_INSN (insn
);
5388 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
5389 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
5394 /* Threading the prologue and epilogue changes the artificial refs
5395 in the entry and exit blocks. */
5396 epilogue_completed
= 1;
5397 df_update_entry_exit_and_calls ();
5400 /* Reposition the prologue-end and epilogue-begin notes after
5401 instruction scheduling. */
5404 reposition_prologue_and_epilogue_notes (void)
5406 #if defined (HAVE_prologue) || defined (HAVE_epilogue) \
5407 || defined (HAVE_sibcall_epilogue)
5408 /* Since the hash table is created on demand, the fact that it is
5409 non-null is a signal that it is non-empty. */
5410 if (prologue_insn_hash
!= NULL
)
5412 size_t len
= htab_elements (prologue_insn_hash
);
5413 rtx insn
, last
= NULL
, note
= NULL
;
5415 /* Scan from the beginning until we reach the last prologue insn. */
5416 /* ??? While we do have the CFG intact, there are two problems:
5417 (1) The prologue can contain loops (typically probing the stack),
5418 which means that the end of the prologue isn't in the first bb.
5419 (2) Sometimes the PROLOGUE_END note gets pushed into the next bb. */
5420 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5424 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5427 else if (contains (insn
, prologue_insn_hash
))
5439 /* Scan forward looking for the PROLOGUE_END note. It should
5440 be right at the beginning of the block, possibly with other
5441 insn notes that got moved there. */
5442 for (note
= NEXT_INSN (last
); ; note
= NEXT_INSN (note
))
5445 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5450 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5452 last
= NEXT_INSN (last
);
5453 reorder_insns (note
, note
, last
);
5457 if (epilogue_insn_hash
!= NULL
)
5462 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
5464 rtx insn
, first
= NULL
, note
= NULL
;
5465 basic_block bb
= e
->src
;
5467 /* Scan from the beginning until we reach the first epilogue insn. */
5468 FOR_BB_INSNS (bb
, insn
)
5472 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5479 else if (first
== NULL
&& contains (insn
, epilogue_insn_hash
))
5489 /* If the function has a single basic block, and no real
5490 epilogue insns (e.g. sibcall with no cleanup), the
5491 epilogue note can get scheduled before the prologue
5492 note. If we have frame related prologue insns, having
5493 them scanned during the epilogue will result in a crash.
5494 In this case re-order the epilogue note to just before
5495 the last insn in the block. */
5497 first
= BB_END (bb
);
5499 if (PREV_INSN (first
) != note
)
5500 reorder_insns (note
, note
, PREV_INSN (first
));
5504 #endif /* HAVE_prologue or HAVE_epilogue */
5507 /* Returns the name of the current function. */
5509 current_function_name (void)
5513 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5518 rest_of_handle_check_leaf_regs (void)
5520 #ifdef LEAF_REGISTERS
5521 current_function_uses_only_leaf_regs
5522 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5527 /* Insert a TYPE into the used types hash table of CFUN. */
5530 used_types_insert_helper (tree type
, struct function
*func
)
5532 if (type
!= NULL
&& func
!= NULL
)
5536 if (func
->used_types_hash
== NULL
)
5537 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5538 htab_eq_pointer
, NULL
);
5539 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5545 /* Given a type, insert it into the used hash table in cfun. */
5547 used_types_insert (tree t
)
5549 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5554 if (TYPE_NAME (t
) == NULL_TREE
5555 || TYPE_NAME (t
) == TYPE_NAME (TYPE_MAIN_VARIANT (t
)))
5556 t
= TYPE_MAIN_VARIANT (t
);
5557 if (debug_info_level
> DINFO_LEVEL_NONE
)
5560 used_types_insert_helper (t
, cfun
);
5562 /* So this might be a type referenced by a global variable.
5563 Record that type so that we can later decide to emit its debug
5565 types_used_by_cur_var_decl
=
5566 tree_cons (t
, NULL
, types_used_by_cur_var_decl
);
5571 /* Helper to Hash a struct types_used_by_vars_entry. */
5574 hash_types_used_by_vars_entry (const struct types_used_by_vars_entry
*entry
)
5576 gcc_assert (entry
&& entry
->var_decl
&& entry
->type
);
5578 return iterative_hash_object (entry
->type
,
5579 iterative_hash_object (entry
->var_decl
, 0));
5582 /* Hash function of the types_used_by_vars_entry hash table. */
5585 types_used_by_vars_do_hash (const void *x
)
5587 const struct types_used_by_vars_entry
*entry
=
5588 (const struct types_used_by_vars_entry
*) x
;
5590 return hash_types_used_by_vars_entry (entry
);
5593 /*Equality function of the types_used_by_vars_entry hash table. */
5596 types_used_by_vars_eq (const void *x1
, const void *x2
)
5598 const struct types_used_by_vars_entry
*e1
=
5599 (const struct types_used_by_vars_entry
*) x1
;
5600 const struct types_used_by_vars_entry
*e2
=
5601 (const struct types_used_by_vars_entry
*)x2
;
5603 return (e1
->var_decl
== e2
->var_decl
&& e1
->type
== e2
->type
);
5606 /* Inserts an entry into the types_used_by_vars_hash hash table. */
5609 types_used_by_var_decl_insert (tree type
, tree var_decl
)
5611 if (type
!= NULL
&& var_decl
!= NULL
)
5614 struct types_used_by_vars_entry e
;
5615 e
.var_decl
= var_decl
;
5617 if (types_used_by_vars_hash
== NULL
)
5618 types_used_by_vars_hash
=
5619 htab_create_ggc (37, types_used_by_vars_do_hash
,
5620 types_used_by_vars_eq
, NULL
);
5621 slot
= htab_find_slot_with_hash (types_used_by_vars_hash
, &e
,
5622 hash_types_used_by_vars_entry (&e
), INSERT
);
5625 struct types_used_by_vars_entry
*entry
;
5626 entry
= ggc_alloc_types_used_by_vars_entry ();
5628 entry
->var_decl
= var_decl
;
5634 struct rtl_opt_pass pass_leaf_regs
=
5638 "*leaf_regs", /* name */
5640 rest_of_handle_check_leaf_regs
, /* execute */
5643 0, /* static_pass_number */
5644 TV_NONE
, /* tv_id */
5645 0, /* properties_required */
5646 0, /* properties_provided */
5647 0, /* properties_destroyed */
5648 0, /* todo_flags_start */
5649 0 /* todo_flags_finish */
5654 rest_of_handle_thread_prologue_and_epilogue (void)
5657 cleanup_cfg (CLEANUP_EXPENSIVE
);
5658 /* On some machines, the prologue and epilogue code, or parts thereof,
5659 can be represented as RTL. Doing so lets us schedule insns between
5660 it and the rest of the code and also allows delayed branch
5661 scheduling to operate in the epilogue. */
5663 thread_prologue_and_epilogue_insns ();
5667 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5671 "pro_and_epilogue", /* name */
5673 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5676 0, /* static_pass_number */
5677 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5678 0, /* properties_required */
5679 0, /* properties_provided */
5680 0, /* properties_destroyed */
5681 TODO_verify_flow
, /* todo_flags_start */
5684 TODO_df_finish
| TODO_verify_rtl_sharing
|
5685 TODO_ggc_collect
/* todo_flags_finish */
5690 /* This mini-pass fixes fall-out from SSA in asm statements that have
5691 in-out constraints. Say you start with
5694 asm ("": "+mr" (inout));
5697 which is transformed very early to use explicit output and match operands:
5700 asm ("": "=mr" (inout) : "0" (inout));
5703 Or, after SSA and copyprop,
5705 asm ("": "=mr" (inout_2) : "0" (inout_1));
5708 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5709 they represent two separate values, so they will get different pseudo
5710 registers during expansion. Then, since the two operands need to match
5711 per the constraints, but use different pseudo registers, reload can
5712 only register a reload for these operands. But reloads can only be
5713 satisfied by hardregs, not by memory, so we need a register for this
5714 reload, just because we are presented with non-matching operands.
5715 So, even though we allow memory for this operand, no memory can be
5716 used for it, just because the two operands don't match. This can
5717 cause reload failures on register-starved targets.
5719 So it's a symptom of reload not being able to use memory for reloads
5720 or, alternatively it's also a symptom of both operands not coming into
5721 reload as matching (in which case the pseudo could go to memory just
5722 fine, as the alternative allows it, and no reload would be necessary).
5723 We fix the latter problem here, by transforming
5725 asm ("": "=mr" (inout_2) : "0" (inout_1));
5730 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5733 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5736 bool changed
= false;
5737 rtx op
= SET_SRC (p_sets
[0]);
5738 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5739 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5740 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
5742 memset (output_matched
, 0, noutputs
* sizeof (bool));
5743 for (i
= 0; i
< ninputs
; i
++)
5745 rtx input
, output
, insns
;
5746 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5750 if (*constraint
== '%')
5753 match
= strtoul (constraint
, &end
, 10);
5754 if (end
== constraint
)
5757 gcc_assert (match
< noutputs
);
5758 output
= SET_DEST (p_sets
[match
]);
5759 input
= RTVEC_ELT (inputs
, i
);
5760 /* Only do the transformation for pseudos. */
5761 if (! REG_P (output
)
5762 || rtx_equal_p (output
, input
)
5763 || (GET_MODE (input
) != VOIDmode
5764 && GET_MODE (input
) != GET_MODE (output
)))
5767 /* We can't do anything if the output is also used as input,
5768 as we're going to overwrite it. */
5769 for (j
= 0; j
< ninputs
; j
++)
5770 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5775 /* Avoid changing the same input several times. For
5776 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5777 only change in once (to out1), rather than changing it
5778 first to out1 and afterwards to out2. */
5781 for (j
= 0; j
< noutputs
; j
++)
5782 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5787 output_matched
[match
] = true;
5790 emit_move_insn (output
, input
);
5791 insns
= get_insns ();
5793 emit_insn_before (insns
, insn
);
5795 /* Now replace all mentions of the input with output. We can't
5796 just replace the occurrence in inputs[i], as the register might
5797 also be used in some other input (or even in an address of an
5798 output), which would mean possibly increasing the number of
5799 inputs by one (namely 'output' in addition), which might pose
5800 a too complicated problem for reload to solve. E.g. this situation:
5802 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5804 Here 'input' is used in two occurrences as input (once for the
5805 input operand, once for the address in the second output operand).
5806 If we would replace only the occurrence of the input operand (to
5807 make the matching) we would be left with this:
5810 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5812 Now we suddenly have two different input values (containing the same
5813 value, but different pseudos) where we formerly had only one.
5814 With more complicated asms this might lead to reload failures
5815 which wouldn't have happen without this pass. So, iterate over
5816 all operands and replace all occurrences of the register used. */
5817 for (j
= 0; j
< noutputs
; j
++)
5818 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5819 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5820 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5822 for (j
= 0; j
< ninputs
; j
++)
5823 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5824 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5831 df_insn_rescan (insn
);
5835 rest_of_match_asm_constraints (void)
5838 rtx insn
, pat
, *p_sets
;
5841 if (!crtl
->has_asm_statement
)
5844 df_set_flags (DF_DEFER_INSN_RESCAN
);
5847 FOR_BB_INSNS (bb
, insn
)
5852 pat
= PATTERN (insn
);
5853 if (GET_CODE (pat
) == PARALLEL
)
5854 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5855 else if (GET_CODE (pat
) == SET
)
5856 p_sets
= &PATTERN (insn
), noutputs
= 1;
5860 if (GET_CODE (*p_sets
) == SET
5861 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5862 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5866 return TODO_df_finish
;
5869 struct rtl_opt_pass pass_match_asm_constraints
=
5873 "asmcons", /* name */
5875 rest_of_match_asm_constraints
, /* execute */
5878 0, /* static_pass_number */
5879 TV_NONE
, /* tv_id */
5880 0, /* properties_required */
5881 0, /* properties_provided */
5882 0, /* properties_destroyed */
5883 0, /* todo_flags_start */
5884 TODO_dump_func
/* todo_flags_finish */
5889 #include "gt-function.h"