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
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
22 /* This file handles the generation of rtl code from tree structure
23 at the level of the function as a whole.
24 It creates the rtl expressions for parameters and auto variables
25 and has full responsibility for allocating stack slots.
27 `expand_function_start' is called at the beginning of a function,
28 before the function body is parsed, and `expand_function_end' is
29 called after parsing the body.
31 Call `assign_stack_local' to allocate a stack slot for a local variable.
32 This is usually done during the RTL generation for the function body,
33 but it can also be done in the reload pass when a pseudo-register does
34 not get a hard register. */
38 #include "coretypes.h"
49 #include "hard-reg-set.h"
50 #include "insn-config.h"
53 #include "basic-block.h"
58 #include "integrate.h"
59 #include "langhooks.h"
61 #include "cfglayout.h"
63 #include "tree-pass.h"
69 /* So we can assign to cfun in this file. */
72 #ifndef STACK_ALIGNMENT_NEEDED
73 #define STACK_ALIGNMENT_NEEDED 1
76 #define STACK_BYTES (STACK_BOUNDARY / BITS_PER_UNIT)
78 /* Some systems use __main in a way incompatible with its use in gcc, in these
79 cases use the macros NAME__MAIN to give a quoted symbol and SYMBOL__MAIN to
80 give the same symbol without quotes for an alternative entry point. You
81 must define both, or neither. */
83 #define NAME__MAIN "__main"
86 /* Round a value to the lowest integer less than it that is a multiple of
87 the required alignment. Avoid using division in case the value is
88 negative. Assume the alignment is a power of two. */
89 #define FLOOR_ROUND(VALUE,ALIGN) ((VALUE) & ~((ALIGN) - 1))
91 /* Similar, but round to the next highest integer that meets the
93 #define CEIL_ROUND(VALUE,ALIGN) (((VALUE) + (ALIGN) - 1) & ~((ALIGN)- 1))
95 /* Nonzero if function being compiled doesn't contain any calls
96 (ignoring the prologue and epilogue). This is set prior to
97 local register allocation and is valid for the remaining
99 int current_function_is_leaf
;
101 /* Nonzero if function being compiled doesn't modify the stack pointer
102 (ignoring the prologue and epilogue). This is only valid after
103 pass_stack_ptr_mod has run. */
104 int current_function_sp_is_unchanging
;
106 /* Nonzero if the function being compiled is a leaf function which only
107 uses leaf registers. This is valid after reload (specifically after
108 sched2) and is useful only if the port defines LEAF_REGISTERS. */
109 int current_function_uses_only_leaf_regs
;
111 /* Nonzero once virtual register instantiation has been done.
112 assign_stack_local uses frame_pointer_rtx when this is nonzero.
113 calls.c:emit_library_call_value_1 uses it to set up
114 post-instantiation libcalls. */
115 int virtuals_instantiated
;
117 /* Assign unique numbers to labels generated for profiling, debugging, etc. */
118 static GTY(()) int funcdef_no
;
120 /* These variables hold pointers to functions to create and destroy
121 target specific, per-function data structures. */
122 struct machine_function
* (*init_machine_status
) (void);
124 /* The currently compiled function. */
125 struct function
*cfun
= 0;
127 /* These arrays record the INSN_UIDs of the prologue and epilogue insns. */
128 static VEC(int,heap
) *prologue
;
129 static VEC(int,heap
) *epilogue
;
131 /* Array of INSN_UIDs to hold the INSN_UIDs for each sibcall epilogue
133 static VEC(int,heap
) *sibcall_epilogue
;
135 /* In order to evaluate some expressions, such as function calls returning
136 structures in memory, we need to temporarily allocate stack locations.
137 We record each allocated temporary in the following structure.
139 Associated with each temporary slot is a nesting level. When we pop up
140 one level, all temporaries associated with the previous level are freed.
141 Normally, all temporaries are freed after the execution of the statement
142 in which they were created. However, if we are inside a ({...}) grouping,
143 the result may be in a temporary and hence must be preserved. If the
144 result could be in a temporary, we preserve it if we can determine which
145 one it is in. If we cannot determine which temporary may contain the
146 result, all temporaries are preserved. A temporary is preserved by
147 pretending it was allocated at the previous nesting level.
149 Automatic variables are also assigned temporary slots, at the nesting
150 level where they are defined. They are marked a "kept" so that
151 free_temp_slots will not free them. */
153 struct temp_slot
GTY(())
155 /* Points to next temporary slot. */
156 struct temp_slot
*next
;
157 /* Points to previous temporary slot. */
158 struct temp_slot
*prev
;
160 /* The rtx to used to reference the slot. */
162 /* The rtx used to represent the address if not the address of the
163 slot above. May be an EXPR_LIST if multiple addresses exist. */
165 /* The alignment (in bits) of the slot. */
167 /* The size, in units, of the slot. */
169 /* The type of the object in the slot, or zero if it doesn't correspond
170 to a type. We use this to determine whether a slot can be reused.
171 It can be reused if objects of the type of the new slot will always
172 conflict with objects of the type of the old slot. */
174 /* Nonzero if this temporary is currently in use. */
176 /* Nonzero if this temporary has its address taken. */
178 /* Nesting level at which this slot is being used. */
180 /* Nonzero if this should survive a call to free_temp_slots. */
182 /* The offset of the slot from the frame_pointer, including extra space
183 for alignment. This info is for combine_temp_slots. */
184 HOST_WIDE_INT base_offset
;
185 /* The size of the slot, including extra space for alignment. This
186 info is for combine_temp_slots. */
187 HOST_WIDE_INT full_size
;
190 /* Forward declarations. */
192 static struct temp_slot
*find_temp_slot_from_address (rtx
);
193 static void pad_to_arg_alignment (struct args_size
*, int, struct args_size
*);
194 static void pad_below (struct args_size
*, enum machine_mode
, tree
);
195 static void reorder_blocks_1 (rtx
, tree
, VEC(tree
,heap
) **);
196 static int all_blocks (tree
, tree
*);
197 static tree
*get_block_vector (tree
, int *);
198 extern tree
debug_find_var_in_block_tree (tree
, tree
);
199 /* We always define `record_insns' even if it's not used so that we
200 can always export `prologue_epilogue_contains'. */
201 static void record_insns (rtx
, VEC(int,heap
) **) ATTRIBUTE_UNUSED
;
202 static int contains (const_rtx
, VEC(int,heap
) **);
204 static void emit_return_into_block (basic_block
);
206 static void prepare_function_start (void);
207 static void do_clobber_return_reg (rtx
, void *);
208 static void do_use_return_reg (rtx
, void *);
209 static void set_insn_locators (rtx
, int) ATTRIBUTE_UNUSED
;
211 /* Pointer to chain of `struct function' for containing functions. */
212 struct function
*outer_function_chain
;
214 /* Given a function decl for a containing function,
215 return the `struct function' for it. */
218 find_function_data (tree decl
)
222 for (p
= outer_function_chain
; p
; p
= p
->outer
)
229 /* Save the current context for compilation of a nested function.
230 This is called from language-specific code. */
233 push_function_context (void)
236 allocate_struct_function (NULL
, false);
238 cfun
->outer
= outer_function_chain
;
239 outer_function_chain
= cfun
;
243 /* Restore the last saved context, at the end of a nested function.
244 This function is called from language-specific code. */
247 pop_function_context (void)
249 struct function
*p
= outer_function_chain
;
252 outer_function_chain
= p
->outer
;
253 current_function_decl
= p
->decl
;
255 /* Reset variables that have known state during rtx generation. */
256 virtuals_instantiated
= 0;
257 generating_concat_p
= 1;
260 /* Clear out all parts of the state in F that can safely be discarded
261 after the function has been parsed, but not compiled, to let
262 garbage collection reclaim the memory. */
265 free_after_parsing (struct function
*f
)
270 /* Clear out all parts of the state in F that can safely be discarded
271 after the function has been compiled, to let garbage collection
272 reclaim the memory. */
275 free_after_compilation (struct function
*f
)
277 VEC_free (int, heap
, prologue
);
278 VEC_free (int, heap
, epilogue
);
279 VEC_free (int, heap
, sibcall_epilogue
);
280 if (crtl
->emit
.regno_pointer_align
)
281 free (crtl
->emit
.regno_pointer_align
);
283 memset (crtl
, 0, sizeof (struct rtl_data
));
288 regno_reg_rtx
= NULL
;
291 /* Return size needed for stack frame based on slots so far allocated.
292 This size counts from zero. It is not rounded to PREFERRED_STACK_BOUNDARY;
293 the caller may have to do that. */
296 get_frame_size (void)
298 if (FRAME_GROWS_DOWNWARD
)
299 return -frame_offset
;
304 /* Issue an error message and return TRUE if frame OFFSET overflows in
305 the signed target pointer arithmetics for function FUNC. Otherwise
309 frame_offset_overflow (HOST_WIDE_INT offset
, tree func
)
311 unsigned HOST_WIDE_INT size
= FRAME_GROWS_DOWNWARD
? -offset
: offset
;
313 if (size
> ((unsigned HOST_WIDE_INT
) 1 << (GET_MODE_BITSIZE (Pmode
) - 1))
314 /* Leave room for the fixed part of the frame. */
315 - 64 * UNITS_PER_WORD
)
317 error ("%Jtotal size of local objects too large", func
);
324 /* Return stack slot alignment in bits for TYPE and MODE. */
327 get_stack_local_alignment (tree type
, enum machine_mode mode
)
329 unsigned int alignment
;
332 alignment
= BIGGEST_ALIGNMENT
;
334 alignment
= GET_MODE_ALIGNMENT (mode
);
336 /* Allow the frond-end to (possibly) increase the alignment of this
339 type
= lang_hooks
.types
.type_for_mode (mode
, 0);
341 return STACK_SLOT_ALIGNMENT (type
, mode
, alignment
);
344 /* Allocate a stack slot of SIZE bytes and return a MEM rtx for it
345 with machine mode MODE.
347 ALIGN controls the amount of alignment for the address of the slot:
348 0 means according to MODE,
349 -1 means use BIGGEST_ALIGNMENT and round size to multiple of that,
350 -2 means use BITS_PER_UNIT,
351 positive specifies alignment boundary in bits.
353 We do not round to stack_boundary here. */
356 assign_stack_local (enum machine_mode mode
, HOST_WIDE_INT size
, int align
)
359 int bigend_correction
= 0;
360 unsigned int alignment
, alignment_in_bits
;
361 int frame_off
, frame_alignment
, frame_phase
;
365 alignment
= get_stack_local_alignment (NULL
, mode
);
366 alignment
/= BITS_PER_UNIT
;
368 else if (align
== -1)
370 alignment
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
371 size
= CEIL_ROUND (size
, alignment
);
373 else if (align
== -2)
374 alignment
= 1; /* BITS_PER_UNIT / BITS_PER_UNIT */
376 alignment
= align
/ BITS_PER_UNIT
;
378 if (FRAME_GROWS_DOWNWARD
)
379 frame_offset
-= size
;
381 /* Ignore alignment we can't do with expected alignment of the boundary. */
382 if (alignment
* BITS_PER_UNIT
> PREFERRED_STACK_BOUNDARY
)
383 alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
385 alignment_in_bits
= alignment
* BITS_PER_UNIT
;
387 if (crtl
->stack_alignment_needed
< alignment_in_bits
)
388 crtl
->stack_alignment_needed
= alignment_in_bits
;
390 /* Calculate how many bytes the start of local variables is off from
392 frame_alignment
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
393 frame_off
= STARTING_FRAME_OFFSET
% frame_alignment
;
394 frame_phase
= frame_off
? frame_alignment
- frame_off
: 0;
396 /* Round the frame offset to the specified alignment. The default is
397 to always honor requests to align the stack but a port may choose to
398 do its own stack alignment by defining STACK_ALIGNMENT_NEEDED. */
399 if (STACK_ALIGNMENT_NEEDED
403 /* We must be careful here, since FRAME_OFFSET might be negative and
404 division with a negative dividend isn't as well defined as we might
405 like. So we instead assume that ALIGNMENT is a power of two and
406 use logical operations which are unambiguous. */
407 if (FRAME_GROWS_DOWNWARD
)
409 = (FLOOR_ROUND (frame_offset
- frame_phase
,
410 (unsigned HOST_WIDE_INT
) alignment
)
414 = (CEIL_ROUND (frame_offset
- frame_phase
,
415 (unsigned HOST_WIDE_INT
) alignment
)
419 /* On a big-endian machine, if we are allocating more space than we will use,
420 use the least significant bytes of those that are allocated. */
421 if (BYTES_BIG_ENDIAN
&& mode
!= BLKmode
&& GET_MODE_SIZE (mode
) < size
)
422 bigend_correction
= size
- GET_MODE_SIZE (mode
);
424 /* If we have already instantiated virtual registers, return the actual
425 address relative to the frame pointer. */
426 if (virtuals_instantiated
)
427 addr
= plus_constant (frame_pointer_rtx
,
429 (frame_offset
+ bigend_correction
430 + STARTING_FRAME_OFFSET
, Pmode
));
432 addr
= plus_constant (virtual_stack_vars_rtx
,
434 (frame_offset
+ bigend_correction
,
437 if (!FRAME_GROWS_DOWNWARD
)
438 frame_offset
+= size
;
440 x
= gen_rtx_MEM (mode
, addr
);
441 set_mem_align (x
, alignment_in_bits
);
442 MEM_NOTRAP_P (x
) = 1;
445 = gen_rtx_EXPR_LIST (VOIDmode
, x
, stack_slot_list
);
447 if (frame_offset_overflow (frame_offset
, current_function_decl
))
453 /* Removes temporary slot TEMP from LIST. */
456 cut_slot_from_list (struct temp_slot
*temp
, struct temp_slot
**list
)
459 temp
->next
->prev
= temp
->prev
;
461 temp
->prev
->next
= temp
->next
;
465 temp
->prev
= temp
->next
= NULL
;
468 /* Inserts temporary slot TEMP to LIST. */
471 insert_slot_to_list (struct temp_slot
*temp
, struct temp_slot
**list
)
475 (*list
)->prev
= temp
;
480 /* Returns the list of used temp slots at LEVEL. */
482 static struct temp_slot
**
483 temp_slots_at_level (int level
)
485 if (level
>= (int) VEC_length (temp_slot_p
, used_temp_slots
))
486 VEC_safe_grow_cleared (temp_slot_p
, gc
, used_temp_slots
, level
+ 1);
488 return &(VEC_address (temp_slot_p
, used_temp_slots
)[level
]);
491 /* Returns the maximal temporary slot level. */
494 max_slot_level (void)
496 if (!used_temp_slots
)
499 return VEC_length (temp_slot_p
, used_temp_slots
) - 1;
502 /* Moves temporary slot TEMP to LEVEL. */
505 move_slot_to_level (struct temp_slot
*temp
, int level
)
507 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
508 insert_slot_to_list (temp
, temp_slots_at_level (level
));
512 /* Make temporary slot TEMP available. */
515 make_slot_available (struct temp_slot
*temp
)
517 cut_slot_from_list (temp
, temp_slots_at_level (temp
->level
));
518 insert_slot_to_list (temp
, &avail_temp_slots
);
523 /* Allocate a temporary stack slot and record it for possible later
526 MODE is the machine mode to be given to the returned rtx.
528 SIZE is the size in units of the space required. We do no rounding here
529 since assign_stack_local will do any required rounding.
531 KEEP is 1 if this slot is to be retained after a call to
532 free_temp_slots. Automatic variables for a block are allocated
533 with this flag. KEEP values of 2 or 3 were needed respectively
534 for variables whose lifetime is controlled by CLEANUP_POINT_EXPRs
535 or for SAVE_EXPRs, but they are now unused.
537 TYPE is the type that will be used for the stack slot. */
540 assign_stack_temp_for_type (enum machine_mode mode
, HOST_WIDE_INT size
,
544 struct temp_slot
*p
, *best_p
= 0, *selected
= NULL
, **pp
;
547 /* If SIZE is -1 it means that somebody tried to allocate a temporary
548 of a variable size. */
549 gcc_assert (size
!= -1);
551 /* These are now unused. */
552 gcc_assert (keep
<= 1);
554 align
= get_stack_local_alignment (type
, mode
);
556 /* Try to find an available, already-allocated temporary of the proper
557 mode which meets the size and alignment requirements. Choose the
558 smallest one with the closest alignment.
560 If assign_stack_temp is called outside of the tree->rtl expansion,
561 we cannot reuse the stack slots (that may still refer to
562 VIRTUAL_STACK_VARS_REGNUM). */
563 if (!virtuals_instantiated
)
565 for (p
= avail_temp_slots
; p
; p
= p
->next
)
567 if (p
->align
>= align
&& p
->size
>= size
568 && GET_MODE (p
->slot
) == mode
569 && objects_must_conflict_p (p
->type
, type
)
570 && (best_p
== 0 || best_p
->size
> p
->size
571 || (best_p
->size
== p
->size
&& best_p
->align
> p
->align
)))
573 if (p
->align
== align
&& p
->size
== size
)
576 cut_slot_from_list (selected
, &avail_temp_slots
);
585 /* Make our best, if any, the one to use. */
589 cut_slot_from_list (selected
, &avail_temp_slots
);
591 /* If there are enough aligned bytes left over, make them into a new
592 temp_slot so that the extra bytes don't get wasted. Do this only
593 for BLKmode slots, so that we can be sure of the alignment. */
594 if (GET_MODE (best_p
->slot
) == BLKmode
)
596 int alignment
= best_p
->align
/ BITS_PER_UNIT
;
597 HOST_WIDE_INT rounded_size
= CEIL_ROUND (size
, alignment
);
599 if (best_p
->size
- rounded_size
>= alignment
)
601 p
= GGC_NEW (struct temp_slot
);
602 p
->in_use
= p
->addr_taken
= 0;
603 p
->size
= best_p
->size
- rounded_size
;
604 p
->base_offset
= best_p
->base_offset
+ rounded_size
;
605 p
->full_size
= best_p
->full_size
- rounded_size
;
606 p
->slot
= adjust_address_nv (best_p
->slot
, BLKmode
, rounded_size
);
607 p
->align
= best_p
->align
;
609 p
->type
= best_p
->type
;
610 insert_slot_to_list (p
, &avail_temp_slots
);
612 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, p
->slot
,
615 best_p
->size
= rounded_size
;
616 best_p
->full_size
= rounded_size
;
621 /* If we still didn't find one, make a new temporary. */
624 HOST_WIDE_INT frame_offset_old
= frame_offset
;
626 p
= GGC_NEW (struct temp_slot
);
628 /* We are passing an explicit alignment request to assign_stack_local.
629 One side effect of that is assign_stack_local will not round SIZE
630 to ensure the frame offset remains suitably aligned.
632 So for requests which depended on the rounding of SIZE, we go ahead
633 and round it now. We also make sure ALIGNMENT is at least
634 BIGGEST_ALIGNMENT. */
635 gcc_assert (mode
!= BLKmode
|| align
== BIGGEST_ALIGNMENT
);
636 p
->slot
= assign_stack_local (mode
,
638 ? CEIL_ROUND (size
, (int) align
/ BITS_PER_UNIT
)
644 /* The following slot size computation is necessary because we don't
645 know the actual size of the temporary slot until assign_stack_local
646 has performed all the frame alignment and size rounding for the
647 requested temporary. Note that extra space added for alignment
648 can be either above or below this stack slot depending on which
649 way the frame grows. We include the extra space if and only if it
650 is above this slot. */
651 if (FRAME_GROWS_DOWNWARD
)
652 p
->size
= frame_offset_old
- frame_offset
;
656 /* Now define the fields used by combine_temp_slots. */
657 if (FRAME_GROWS_DOWNWARD
)
659 p
->base_offset
= frame_offset
;
660 p
->full_size
= frame_offset_old
- frame_offset
;
664 p
->base_offset
= frame_offset_old
;
665 p
->full_size
= frame_offset
- frame_offset_old
;
676 p
->level
= temp_slot_level
;
679 pp
= temp_slots_at_level (p
->level
);
680 insert_slot_to_list (p
, pp
);
682 /* Create a new MEM rtx to avoid clobbering MEM flags of old slots. */
683 slot
= gen_rtx_MEM (mode
, XEXP (p
->slot
, 0));
684 stack_slot_list
= gen_rtx_EXPR_LIST (VOIDmode
, slot
, stack_slot_list
);
686 /* If we know the alias set for the memory that will be used, use
687 it. If there's no TYPE, then we don't know anything about the
688 alias set for the memory. */
689 set_mem_alias_set (slot
, type
? get_alias_set (type
) : 0);
690 set_mem_align (slot
, align
);
692 /* If a type is specified, set the relevant flags. */
695 MEM_VOLATILE_P (slot
) = TYPE_VOLATILE (type
);
696 MEM_SET_IN_STRUCT_P (slot
, (AGGREGATE_TYPE_P (type
)
697 || TREE_CODE (type
) == COMPLEX_TYPE
));
699 MEM_NOTRAP_P (slot
) = 1;
704 /* Allocate a temporary stack slot and record it for possible later
705 reuse. First three arguments are same as in preceding function. */
708 assign_stack_temp (enum machine_mode mode
, HOST_WIDE_INT size
, int keep
)
710 return assign_stack_temp_for_type (mode
, size
, keep
, NULL_TREE
);
713 /* Assign a temporary.
714 If TYPE_OR_DECL is a decl, then we are doing it on behalf of the decl
715 and so that should be used in error messages. In either case, we
716 allocate of the given type.
717 KEEP is as for assign_stack_temp.
718 MEMORY_REQUIRED is 1 if the result must be addressable stack memory;
719 it is 0 if a register is OK.
720 DONT_PROMOTE is 1 if we should not promote values in register
724 assign_temp (tree type_or_decl
, int keep
, int memory_required
,
725 int dont_promote ATTRIBUTE_UNUSED
)
728 enum machine_mode mode
;
733 if (DECL_P (type_or_decl
))
734 decl
= type_or_decl
, type
= TREE_TYPE (decl
);
736 decl
= NULL
, type
= type_or_decl
;
738 mode
= TYPE_MODE (type
);
740 unsignedp
= TYPE_UNSIGNED (type
);
743 if (mode
== BLKmode
|| memory_required
)
745 HOST_WIDE_INT size
= int_size_in_bytes (type
);
748 /* Zero sized arrays are GNU C extension. Set size to 1 to avoid
749 problems with allocating the stack space. */
753 /* Unfortunately, we don't yet know how to allocate variable-sized
754 temporaries. However, sometimes we can find a fixed upper limit on
755 the size, so try that instead. */
757 size
= max_int_size_in_bytes (type
);
759 /* The size of the temporary may be too large to fit into an integer. */
760 /* ??? Not sure this should happen except for user silliness, so limit
761 this to things that aren't compiler-generated temporaries. The
762 rest of the time we'll die in assign_stack_temp_for_type. */
763 if (decl
&& size
== -1
764 && TREE_CODE (TYPE_SIZE_UNIT (type
)) == INTEGER_CST
)
766 error ("size of variable %q+D is too large", decl
);
770 tmp
= assign_stack_temp_for_type (mode
, size
, keep
, type
);
776 mode
= promote_mode (type
, mode
, &unsignedp
, 0);
779 return gen_reg_rtx (mode
);
782 /* Combine temporary stack slots which are adjacent on the stack.
784 This allows for better use of already allocated stack space. This is only
785 done for BLKmode slots because we can be sure that we won't have alignment
786 problems in this case. */
789 combine_temp_slots (void)
791 struct temp_slot
*p
, *q
, *next
, *next_q
;
794 /* We can't combine slots, because the information about which slot
795 is in which alias set will be lost. */
796 if (flag_strict_aliasing
)
799 /* If there are a lot of temp slots, don't do anything unless
800 high levels of optimization. */
801 if (! flag_expensive_optimizations
)
802 for (p
= avail_temp_slots
, num_slots
= 0; p
; p
= p
->next
, num_slots
++)
803 if (num_slots
> 100 || (num_slots
> 10 && optimize
== 0))
806 for (p
= avail_temp_slots
; p
; p
= next
)
812 if (GET_MODE (p
->slot
) != BLKmode
)
815 for (q
= p
->next
; q
; q
= next_q
)
821 if (GET_MODE (q
->slot
) != BLKmode
)
824 if (p
->base_offset
+ p
->full_size
== q
->base_offset
)
826 /* Q comes after P; combine Q into P. */
828 p
->full_size
+= q
->full_size
;
831 else if (q
->base_offset
+ q
->full_size
== p
->base_offset
)
833 /* P comes after Q; combine P into Q. */
835 q
->full_size
+= p
->full_size
;
840 cut_slot_from_list (q
, &avail_temp_slots
);
843 /* Either delete P or advance past it. */
845 cut_slot_from_list (p
, &avail_temp_slots
);
849 /* Find the temp slot corresponding to the object at address X. */
851 static struct temp_slot
*
852 find_temp_slot_from_address (rtx x
)
858 for (i
= max_slot_level (); i
>= 0; i
--)
859 for (p
= *temp_slots_at_level (i
); p
; p
= p
->next
)
861 if (XEXP (p
->slot
, 0) == x
863 || (GET_CODE (x
) == PLUS
864 && XEXP (x
, 0) == virtual_stack_vars_rtx
865 && GET_CODE (XEXP (x
, 1)) == CONST_INT
866 && INTVAL (XEXP (x
, 1)) >= p
->base_offset
867 && INTVAL (XEXP (x
, 1)) < p
->base_offset
+ p
->full_size
))
870 else if (p
->address
!= 0 && GET_CODE (p
->address
) == EXPR_LIST
)
871 for (next
= p
->address
; next
; next
= XEXP (next
, 1))
872 if (XEXP (next
, 0) == x
)
876 /* If we have a sum involving a register, see if it points to a temp
878 if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 0))
879 && (p
= find_temp_slot_from_address (XEXP (x
, 0))) != 0)
881 else if (GET_CODE (x
) == PLUS
&& REG_P (XEXP (x
, 1))
882 && (p
= find_temp_slot_from_address (XEXP (x
, 1))) != 0)
888 /* Indicate that NEW is an alternate way of referring to the temp slot
889 that previously was known by OLD. */
892 update_temp_slot_address (rtx old
, rtx
new)
896 if (rtx_equal_p (old
, new))
899 p
= find_temp_slot_from_address (old
);
901 /* If we didn't find one, see if both OLD is a PLUS. If so, and NEW
902 is a register, see if one operand of the PLUS is a temporary
903 location. If so, NEW points into it. Otherwise, if both OLD and
904 NEW are a PLUS and if there is a register in common between them.
905 If so, try a recursive call on those values. */
908 if (GET_CODE (old
) != PLUS
)
913 update_temp_slot_address (XEXP (old
, 0), new);
914 update_temp_slot_address (XEXP (old
, 1), new);
917 else if (GET_CODE (new) != PLUS
)
920 if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 0)))
921 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 1));
922 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 0)))
923 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 1));
924 else if (rtx_equal_p (XEXP (old
, 0), XEXP (new, 1)))
925 update_temp_slot_address (XEXP (old
, 1), XEXP (new, 0));
926 else if (rtx_equal_p (XEXP (old
, 1), XEXP (new, 1)))
927 update_temp_slot_address (XEXP (old
, 0), XEXP (new, 0));
932 /* Otherwise add an alias for the temp's address. */
933 else if (p
->address
== 0)
937 if (GET_CODE (p
->address
) != EXPR_LIST
)
938 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, p
->address
, NULL_RTX
);
940 p
->address
= gen_rtx_EXPR_LIST (VOIDmode
, new, p
->address
);
944 /* If X could be a reference to a temporary slot, mark the fact that its
945 address was taken. */
948 mark_temp_addr_taken (rtx x
)
955 /* If X is not in memory or is at a constant address, it cannot be in
957 if (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0)))
960 p
= find_temp_slot_from_address (XEXP (x
, 0));
965 /* If X could be a reference to a temporary slot, mark that slot as
966 belonging to the to one level higher than the current level. If X
967 matched one of our slots, just mark that one. Otherwise, we can't
968 easily predict which it is, so upgrade all of them. Kept slots
971 This is called when an ({...}) construct occurs and a statement
972 returns a value in memory. */
975 preserve_temp_slots (rtx x
)
977 struct temp_slot
*p
= 0, *next
;
979 /* If there is no result, we still might have some objects whose address
980 were taken, so we need to make sure they stay around. */
983 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
988 move_slot_to_level (p
, temp_slot_level
- 1);
994 /* If X is a register that is being used as a pointer, see if we have
995 a temporary slot we know it points to. To be consistent with
996 the code below, we really should preserve all non-kept slots
997 if we can't find a match, but that seems to be much too costly. */
998 if (REG_P (x
) && REG_POINTER (x
))
999 p
= find_temp_slot_from_address (x
);
1001 /* If X is not in memory or is at a constant address, it cannot be in
1002 a temporary slot, but it can contain something whose address was
1004 if (p
== 0 && (!MEM_P (x
) || CONSTANT_P (XEXP (x
, 0))))
1006 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1011 move_slot_to_level (p
, temp_slot_level
- 1);
1017 /* First see if we can find a match. */
1019 p
= find_temp_slot_from_address (XEXP (x
, 0));
1023 /* Move everything at our level whose address was taken to our new
1024 level in case we used its address. */
1025 struct temp_slot
*q
;
1027 if (p
->level
== temp_slot_level
)
1029 for (q
= *temp_slots_at_level (temp_slot_level
); q
; q
= next
)
1033 if (p
!= q
&& q
->addr_taken
)
1034 move_slot_to_level (q
, temp_slot_level
- 1);
1037 move_slot_to_level (p
, temp_slot_level
- 1);
1043 /* Otherwise, preserve all non-kept slots at this level. */
1044 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1049 move_slot_to_level (p
, temp_slot_level
- 1);
1053 /* Free all temporaries used so far. This is normally called at the
1054 end of generating code for a statement. */
1057 free_temp_slots (void)
1059 struct temp_slot
*p
, *next
;
1061 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1066 make_slot_available (p
);
1069 combine_temp_slots ();
1072 /* Push deeper into the nesting level for stack temporaries. */
1075 push_temp_slots (void)
1080 /* Pop a temporary nesting level. All slots in use in the current level
1084 pop_temp_slots (void)
1086 struct temp_slot
*p
, *next
;
1088 for (p
= *temp_slots_at_level (temp_slot_level
); p
; p
= next
)
1091 make_slot_available (p
);
1094 combine_temp_slots ();
1099 /* Initialize temporary slots. */
1102 init_temp_slots (void)
1104 /* We have not allocated any temporaries yet. */
1105 avail_temp_slots
= 0;
1106 used_temp_slots
= 0;
1107 temp_slot_level
= 0;
1110 /* These routines are responsible for converting virtual register references
1111 to the actual hard register references once RTL generation is complete.
1113 The following four variables are used for communication between the
1114 routines. They contain the offsets of the virtual registers from their
1115 respective hard registers. */
1117 static int in_arg_offset
;
1118 static int var_offset
;
1119 static int dynamic_offset
;
1120 static int out_arg_offset
;
1121 static int cfa_offset
;
1123 /* In most machines, the stack pointer register is equivalent to the bottom
1126 #ifndef STACK_POINTER_OFFSET
1127 #define STACK_POINTER_OFFSET 0
1130 /* If not defined, pick an appropriate default for the offset of dynamically
1131 allocated memory depending on the value of ACCUMULATE_OUTGOING_ARGS,
1132 REG_PARM_STACK_SPACE, and OUTGOING_REG_PARM_STACK_SPACE. */
1134 #ifndef STACK_DYNAMIC_OFFSET
1136 /* The bottom of the stack points to the actual arguments. If
1137 REG_PARM_STACK_SPACE is defined, this includes the space for the register
1138 parameters. However, if OUTGOING_REG_PARM_STACK space is not defined,
1139 stack space for register parameters is not pushed by the caller, but
1140 rather part of the fixed stack areas and hence not included in
1141 `crtl->outgoing_args_size'. Nevertheless, we must allow
1142 for it when allocating stack dynamic objects. */
1144 #if defined(REG_PARM_STACK_SPACE)
1145 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1146 ((ACCUMULATE_OUTGOING_ARGS \
1147 ? (crtl->outgoing_args_size \
1148 + (OUTGOING_REG_PARM_STACK_SPACE ((!(FNDECL) ? NULL_TREE : TREE_TYPE (FNDECL))) ? 0 \
1149 : REG_PARM_STACK_SPACE (FNDECL))) \
1150 : 0) + (STACK_POINTER_OFFSET))
1152 #define STACK_DYNAMIC_OFFSET(FNDECL) \
1153 ((ACCUMULATE_OUTGOING_ARGS ? crtl->outgoing_args_size : 0) \
1154 + (STACK_POINTER_OFFSET))
1159 /* Given a piece of RTX and a pointer to a HOST_WIDE_INT, if the RTX
1160 is a virtual register, return the equivalent hard register and set the
1161 offset indirectly through the pointer. Otherwise, return 0. */
1164 instantiate_new_reg (rtx x
, HOST_WIDE_INT
*poffset
)
1167 HOST_WIDE_INT offset
;
1169 if (x
== virtual_incoming_args_rtx
)
1170 new = arg_pointer_rtx
, offset
= in_arg_offset
;
1171 else if (x
== virtual_stack_vars_rtx
)
1172 new = frame_pointer_rtx
, offset
= var_offset
;
1173 else if (x
== virtual_stack_dynamic_rtx
)
1174 new = stack_pointer_rtx
, offset
= dynamic_offset
;
1175 else if (x
== virtual_outgoing_args_rtx
)
1176 new = stack_pointer_rtx
, offset
= out_arg_offset
;
1177 else if (x
== virtual_cfa_rtx
)
1179 #ifdef FRAME_POINTER_CFA_OFFSET
1180 new = frame_pointer_rtx
;
1182 new = arg_pointer_rtx
;
1184 offset
= cfa_offset
;
1193 /* A subroutine of instantiate_virtual_regs, called via for_each_rtx.
1194 Instantiate any virtual registers present inside of *LOC. The expression
1195 is simplified, as much as possible, but is not to be considered "valid"
1196 in any sense implied by the target. If any change is made, set CHANGED
1200 instantiate_virtual_regs_in_rtx (rtx
*loc
, void *data
)
1202 HOST_WIDE_INT offset
;
1203 bool *changed
= (bool *) data
;
1210 switch (GET_CODE (x
))
1213 new = instantiate_new_reg (x
, &offset
);
1216 *loc
= plus_constant (new, offset
);
1223 new = instantiate_new_reg (XEXP (x
, 0), &offset
);
1226 new = plus_constant (new, offset
);
1227 *loc
= simplify_gen_binary (PLUS
, GET_MODE (x
), new, XEXP (x
, 1));
1233 /* FIXME -- from old code */
1234 /* If we have (plus (subreg (virtual-reg)) (const_int)), we know
1235 we can commute the PLUS and SUBREG because pointers into the
1236 frame are well-behaved. */
1246 /* A subroutine of instantiate_virtual_regs_in_insn. Return true if X
1247 matches the predicate for insn CODE operand OPERAND. */
1250 safe_insn_predicate (int code
, int operand
, rtx x
)
1252 const struct insn_operand_data
*op_data
;
1257 op_data
= &insn_data
[code
].operand
[operand
];
1258 if (op_data
->predicate
== NULL
)
1261 return op_data
->predicate (x
, op_data
->mode
);
1264 /* A subroutine of instantiate_virtual_regs. Instantiate any virtual
1265 registers present inside of insn. The result will be a valid insn. */
1268 instantiate_virtual_regs_in_insn (rtx insn
)
1270 HOST_WIDE_INT offset
;
1272 bool any_change
= false;
1273 rtx set
, new, x
, seq
;
1275 /* There are some special cases to be handled first. */
1276 set
= single_set (insn
);
1279 /* We're allowed to assign to a virtual register. This is interpreted
1280 to mean that the underlying register gets assigned the inverse
1281 transformation. This is used, for example, in the handling of
1283 new = instantiate_new_reg (SET_DEST (set
), &offset
);
1288 for_each_rtx (&SET_SRC (set
), instantiate_virtual_regs_in_rtx
, NULL
);
1289 x
= simplify_gen_binary (PLUS
, GET_MODE (new), SET_SRC (set
),
1291 x
= force_operand (x
, new);
1293 emit_move_insn (new, x
);
1298 emit_insn_before (seq
, insn
);
1303 /* Handle a straight copy from a virtual register by generating a
1304 new add insn. The difference between this and falling through
1305 to the generic case is avoiding a new pseudo and eliminating a
1306 move insn in the initial rtl stream. */
1307 new = instantiate_new_reg (SET_SRC (set
), &offset
);
1308 if (new && offset
!= 0
1309 && REG_P (SET_DEST (set
))
1310 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1314 x
= expand_simple_binop (GET_MODE (SET_DEST (set
)), PLUS
,
1315 new, GEN_INT (offset
), SET_DEST (set
),
1316 1, OPTAB_LIB_WIDEN
);
1317 if (x
!= SET_DEST (set
))
1318 emit_move_insn (SET_DEST (set
), x
);
1323 emit_insn_before (seq
, insn
);
1328 extract_insn (insn
);
1329 insn_code
= INSN_CODE (insn
);
1331 /* Handle a plus involving a virtual register by determining if the
1332 operands remain valid if they're modified in place. */
1333 if (GET_CODE (SET_SRC (set
)) == PLUS
1334 && recog_data
.n_operands
>= 3
1335 && recog_data
.operand_loc
[1] == &XEXP (SET_SRC (set
), 0)
1336 && recog_data
.operand_loc
[2] == &XEXP (SET_SRC (set
), 1)
1337 && GET_CODE (recog_data
.operand
[2]) == CONST_INT
1338 && (new = instantiate_new_reg (recog_data
.operand
[1], &offset
)))
1340 offset
+= INTVAL (recog_data
.operand
[2]);
1342 /* If the sum is zero, then replace with a plain move. */
1344 && REG_P (SET_DEST (set
))
1345 && REGNO (SET_DEST (set
)) > LAST_VIRTUAL_REGISTER
)
1348 emit_move_insn (SET_DEST (set
), new);
1352 emit_insn_before (seq
, insn
);
1357 x
= gen_int_mode (offset
, recog_data
.operand_mode
[2]);
1359 /* Using validate_change and apply_change_group here leaves
1360 recog_data in an invalid state. Since we know exactly what
1361 we want to check, do those two by hand. */
1362 if (safe_insn_predicate (insn_code
, 1, new)
1363 && safe_insn_predicate (insn_code
, 2, x
))
1365 *recog_data
.operand_loc
[1] = recog_data
.operand
[1] = new;
1366 *recog_data
.operand_loc
[2] = recog_data
.operand
[2] = x
;
1369 /* Fall through into the regular operand fixup loop in
1370 order to take care of operands other than 1 and 2. */
1376 extract_insn (insn
);
1377 insn_code
= INSN_CODE (insn
);
1380 /* In the general case, we expect virtual registers to appear only in
1381 operands, and then only as either bare registers or inside memories. */
1382 for (i
= 0; i
< recog_data
.n_operands
; ++i
)
1384 x
= recog_data
.operand
[i
];
1385 switch (GET_CODE (x
))
1389 rtx addr
= XEXP (x
, 0);
1390 bool changed
= false;
1392 for_each_rtx (&addr
, instantiate_virtual_regs_in_rtx
, &changed
);
1397 x
= replace_equiv_address (x
, addr
);
1398 /* It may happen that the address with the virtual reg
1399 was valid (e.g. based on the virtual stack reg, which might
1400 be acceptable to the predicates with all offsets), whereas
1401 the address now isn't anymore, for instance when the address
1402 is still offsetted, but the base reg isn't virtual-stack-reg
1403 anymore. Below we would do a force_reg on the whole operand,
1404 but this insn might actually only accept memory. Hence,
1405 before doing that last resort, try to reload the address into
1406 a register, so this operand stays a MEM. */
1407 if (!safe_insn_predicate (insn_code
, i
, x
))
1409 addr
= force_reg (GET_MODE (addr
), addr
);
1410 x
= replace_equiv_address (x
, addr
);
1415 emit_insn_before (seq
, insn
);
1420 new = instantiate_new_reg (x
, &offset
);
1429 /* Careful, special mode predicates may have stuff in
1430 insn_data[insn_code].operand[i].mode that isn't useful
1431 to us for computing a new value. */
1432 /* ??? Recognize address_operand and/or "p" constraints
1433 to see if (plus new offset) is a valid before we put
1434 this through expand_simple_binop. */
1435 x
= expand_simple_binop (GET_MODE (x
), PLUS
, new,
1436 GEN_INT (offset
), NULL_RTX
,
1437 1, OPTAB_LIB_WIDEN
);
1440 emit_insn_before (seq
, insn
);
1445 new = instantiate_new_reg (SUBREG_REG (x
), &offset
);
1451 new = expand_simple_binop (GET_MODE (new), PLUS
, new,
1452 GEN_INT (offset
), NULL_RTX
,
1453 1, OPTAB_LIB_WIDEN
);
1456 emit_insn_before (seq
, insn
);
1458 x
= simplify_gen_subreg (recog_data
.operand_mode
[i
], new,
1459 GET_MODE (new), SUBREG_BYTE (x
));
1466 /* At this point, X contains the new value for the operand.
1467 Validate the new value vs the insn predicate. Note that
1468 asm insns will have insn_code -1 here. */
1469 if (!safe_insn_predicate (insn_code
, i
, x
))
1472 x
= force_reg (insn_data
[insn_code
].operand
[i
].mode
, x
);
1476 emit_insn_before (seq
, insn
);
1479 *recog_data
.operand_loc
[i
] = recog_data
.operand
[i
] = x
;
1485 /* Propagate operand changes into the duplicates. */
1486 for (i
= 0; i
< recog_data
.n_dups
; ++i
)
1487 *recog_data
.dup_loc
[i
]
1488 = copy_rtx (recog_data
.operand
[(unsigned)recog_data
.dup_num
[i
]]);
1490 /* Force re-recognition of the instruction for validation. */
1491 INSN_CODE (insn
) = -1;
1494 if (asm_noperands (PATTERN (insn
)) >= 0)
1496 if (!check_asm_operands (PATTERN (insn
)))
1498 error_for_asm (insn
, "impossible constraint in %<asm%>");
1504 if (recog_memoized (insn
) < 0)
1505 fatal_insn_not_found (insn
);
1509 /* Subroutine of instantiate_decls. Given RTL representing a decl,
1510 do any instantiation required. */
1513 instantiate_decl_rtl (rtx x
)
1520 /* If this is a CONCAT, recurse for the pieces. */
1521 if (GET_CODE (x
) == CONCAT
)
1523 instantiate_decl_rtl (XEXP (x
, 0));
1524 instantiate_decl_rtl (XEXP (x
, 1));
1528 /* If this is not a MEM, no need to do anything. Similarly if the
1529 address is a constant or a register that is not a virtual register. */
1534 if (CONSTANT_P (addr
)
1536 && (REGNO (addr
) < FIRST_VIRTUAL_REGISTER
1537 || REGNO (addr
) > LAST_VIRTUAL_REGISTER
)))
1540 for_each_rtx (&XEXP (x
, 0), instantiate_virtual_regs_in_rtx
, NULL
);
1543 /* Helper for instantiate_decls called via walk_tree: Process all decls
1544 in the given DECL_VALUE_EXPR. */
1547 instantiate_expr (tree
*tp
, int *walk_subtrees
, void *data ATTRIBUTE_UNUSED
)
1553 if (DECL_P (t
) && DECL_RTL_SET_P (t
))
1554 instantiate_decl_rtl (DECL_RTL (t
));
1559 /* Subroutine of instantiate_decls: Process all decls in the given
1560 BLOCK node and all its subblocks. */
1563 instantiate_decls_1 (tree let
)
1567 for (t
= BLOCK_VARS (let
); t
; t
= TREE_CHAIN (t
))
1569 if (DECL_RTL_SET_P (t
))
1570 instantiate_decl_rtl (DECL_RTL (t
));
1571 if (TREE_CODE (t
) == VAR_DECL
&& DECL_HAS_VALUE_EXPR_P (t
))
1573 tree v
= DECL_VALUE_EXPR (t
);
1574 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1578 /* Process all subblocks. */
1579 for (t
= BLOCK_SUBBLOCKS (let
); t
; t
= BLOCK_CHAIN (t
))
1580 instantiate_decls_1 (t
);
1583 /* Scan all decls in FNDECL (both variables and parameters) and instantiate
1584 all virtual registers in their DECL_RTL's. */
1587 instantiate_decls (tree fndecl
)
1591 /* Process all parameters of the function. */
1592 for (decl
= DECL_ARGUMENTS (fndecl
); decl
; decl
= TREE_CHAIN (decl
))
1594 instantiate_decl_rtl (DECL_RTL (decl
));
1595 instantiate_decl_rtl (DECL_INCOMING_RTL (decl
));
1596 if (DECL_HAS_VALUE_EXPR_P (decl
))
1598 tree v
= DECL_VALUE_EXPR (decl
);
1599 walk_tree (&v
, instantiate_expr
, NULL
, NULL
);
1603 /* Now process all variables defined in the function or its subblocks. */
1604 instantiate_decls_1 (DECL_INITIAL (fndecl
));
1607 /* Pass through the INSNS of function FNDECL and convert virtual register
1608 references to hard register references. */
1611 instantiate_virtual_regs (void)
1615 /* Compute the offsets to use for this function. */
1616 in_arg_offset
= FIRST_PARM_OFFSET (current_function_decl
);
1617 var_offset
= STARTING_FRAME_OFFSET
;
1618 dynamic_offset
= STACK_DYNAMIC_OFFSET (current_function_decl
);
1619 out_arg_offset
= STACK_POINTER_OFFSET
;
1620 #ifdef FRAME_POINTER_CFA_OFFSET
1621 cfa_offset
= FRAME_POINTER_CFA_OFFSET (current_function_decl
);
1623 cfa_offset
= ARG_POINTER_CFA_OFFSET (current_function_decl
);
1626 /* Initialize recognition, indicating that volatile is OK. */
1629 /* Scan through all the insns, instantiating every virtual register still
1631 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
1634 /* These patterns in the instruction stream can never be recognized.
1635 Fortunately, they shouldn't contain virtual registers either. */
1636 if (GET_CODE (PATTERN (insn
)) == USE
1637 || GET_CODE (PATTERN (insn
)) == CLOBBER
1638 || GET_CODE (PATTERN (insn
)) == ADDR_VEC
1639 || GET_CODE (PATTERN (insn
)) == ADDR_DIFF_VEC
1640 || GET_CODE (PATTERN (insn
)) == ASM_INPUT
)
1643 instantiate_virtual_regs_in_insn (insn
);
1645 if (INSN_DELETED_P (insn
))
1648 for_each_rtx (®_NOTES (insn
), instantiate_virtual_regs_in_rtx
, NULL
);
1650 /* Instantiate any virtual registers in CALL_INSN_FUNCTION_USAGE. */
1651 if (GET_CODE (insn
) == CALL_INSN
)
1652 for_each_rtx (&CALL_INSN_FUNCTION_USAGE (insn
),
1653 instantiate_virtual_regs_in_rtx
, NULL
);
1656 /* Instantiate the virtual registers in the DECLs for debugging purposes. */
1657 instantiate_decls (current_function_decl
);
1659 targetm
.instantiate_decls ();
1661 /* Indicate that, from now on, assign_stack_local should use
1662 frame_pointer_rtx. */
1663 virtuals_instantiated
= 1;
1667 struct rtl_opt_pass pass_instantiate_virtual_regs
=
1673 instantiate_virtual_regs
, /* execute */
1676 0, /* static_pass_number */
1678 0, /* properties_required */
1679 0, /* properties_provided */
1680 0, /* properties_destroyed */
1681 0, /* todo_flags_start */
1682 TODO_dump_func
/* todo_flags_finish */
1687 /* Return 1 if EXP is an aggregate type (or a value with aggregate type).
1688 This means a type for which function calls must pass an address to the
1689 function or get an address back from the function.
1690 EXP may be a type node or an expression (whose type is tested). */
1693 aggregate_value_p (const_tree exp
, const_tree fntype
)
1695 int i
, regno
, nregs
;
1698 const_tree type
= (TYPE_P (exp
)) ? exp
: TREE_TYPE (exp
);
1700 /* DECL node associated with FNTYPE when relevant, which we might need to
1701 check for by-invisible-reference returns, typically for CALL_EXPR input
1703 const_tree fndecl
= NULL_TREE
;
1706 switch (TREE_CODE (fntype
))
1709 fndecl
= get_callee_fndecl (fntype
);
1710 fntype
= fndecl
? TREE_TYPE (fndecl
) : 0;
1714 fntype
= TREE_TYPE (fndecl
);
1719 case IDENTIFIER_NODE
:
1723 /* We don't expect other rtl types here. */
1727 if (TREE_CODE (type
) == VOID_TYPE
)
1730 /* If the front end has decided that this needs to be passed by
1731 reference, do so. */
1732 if ((TREE_CODE (exp
) == PARM_DECL
|| TREE_CODE (exp
) == RESULT_DECL
)
1733 && DECL_BY_REFERENCE (exp
))
1736 /* If the EXPression is a CALL_EXPR, honor DECL_BY_REFERENCE set on the
1737 called function RESULT_DECL, meaning the function returns in memory by
1738 invisible reference. This check lets front-ends not set TREE_ADDRESSABLE
1739 on the function type, which used to be the way to request such a return
1740 mechanism but might now be causing troubles at gimplification time if
1741 temporaries with the function type need to be created. */
1742 if (TREE_CODE (exp
) == CALL_EXPR
&& fndecl
&& DECL_RESULT (fndecl
)
1743 && DECL_BY_REFERENCE (DECL_RESULT (fndecl
)))
1746 if (targetm
.calls
.return_in_memory (type
, fntype
))
1748 /* Types that are TREE_ADDRESSABLE must be constructed in memory,
1749 and thus can't be returned in registers. */
1750 if (TREE_ADDRESSABLE (type
))
1752 if (flag_pcc_struct_return
&& AGGREGATE_TYPE_P (type
))
1754 /* Make sure we have suitable call-clobbered regs to return
1755 the value in; if not, we must return it in memory. */
1756 reg
= hard_function_value (type
, 0, fntype
, 0);
1758 /* If we have something other than a REG (e.g. a PARALLEL), then assume
1763 regno
= REGNO (reg
);
1764 nregs
= hard_regno_nregs
[regno
][TYPE_MODE (type
)];
1765 for (i
= 0; i
< nregs
; i
++)
1766 if (! call_used_regs
[regno
+ i
])
1771 /* Return true if we should assign DECL a pseudo register; false if it
1772 should live on the local stack. */
1775 use_register_for_decl (const_tree decl
)
1777 if (!targetm
.calls
.allocate_stack_slots_for_args())
1780 /* Honor volatile. */
1781 if (TREE_SIDE_EFFECTS (decl
))
1784 /* Honor addressability. */
1785 if (TREE_ADDRESSABLE (decl
))
1788 /* Only register-like things go in registers. */
1789 if (DECL_MODE (decl
) == BLKmode
)
1792 /* If -ffloat-store specified, don't put explicit float variables
1794 /* ??? This should be checked after DECL_ARTIFICIAL, but tree-ssa
1795 propagates values across these stores, and it probably shouldn't. */
1796 if (flag_float_store
&& FLOAT_TYPE_P (TREE_TYPE (decl
)))
1799 /* If we're not interested in tracking debugging information for
1800 this decl, then we can certainly put it in a register. */
1801 if (DECL_IGNORED_P (decl
))
1804 return (optimize
|| DECL_REGISTER (decl
));
1807 /* Return true if TYPE should be passed by invisible reference. */
1810 pass_by_reference (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1811 tree type
, bool named_arg
)
1815 /* If this type contains non-trivial constructors, then it is
1816 forbidden for the middle-end to create any new copies. */
1817 if (TREE_ADDRESSABLE (type
))
1820 /* GCC post 3.4 passes *all* variable sized types by reference. */
1821 if (!TYPE_SIZE (type
) || TREE_CODE (TYPE_SIZE (type
)) != INTEGER_CST
)
1825 return targetm
.calls
.pass_by_reference (ca
, mode
, type
, named_arg
);
1828 /* Return true if TYPE, which is passed by reference, should be callee
1829 copied instead of caller copied. */
1832 reference_callee_copied (CUMULATIVE_ARGS
*ca
, enum machine_mode mode
,
1833 tree type
, bool named_arg
)
1835 if (type
&& TREE_ADDRESSABLE (type
))
1837 return targetm
.calls
.callee_copies (ca
, mode
, type
, named_arg
);
1840 /* Structures to communicate between the subroutines of assign_parms.
1841 The first holds data persistent across all parameters, the second
1842 is cleared out for each parameter. */
1844 struct assign_parm_data_all
1846 CUMULATIVE_ARGS args_so_far
;
1847 struct args_size stack_args_size
;
1848 tree function_result_decl
;
1850 rtx first_conversion_insn
;
1851 rtx last_conversion_insn
;
1852 HOST_WIDE_INT pretend_args_size
;
1853 HOST_WIDE_INT extra_pretend_bytes
;
1854 int reg_parm_stack_space
;
1857 struct assign_parm_data_one
1863 enum machine_mode nominal_mode
;
1864 enum machine_mode passed_mode
;
1865 enum machine_mode promoted_mode
;
1866 struct locate_and_pad_arg_data locate
;
1868 BOOL_BITFIELD named_arg
: 1;
1869 BOOL_BITFIELD passed_pointer
: 1;
1870 BOOL_BITFIELD on_stack
: 1;
1871 BOOL_BITFIELD loaded_in_reg
: 1;
1874 /* A subroutine of assign_parms. Initialize ALL. */
1877 assign_parms_initialize_all (struct assign_parm_data_all
*all
)
1881 memset (all
, 0, sizeof (*all
));
1883 fntype
= TREE_TYPE (current_function_decl
);
1885 #ifdef INIT_CUMULATIVE_INCOMING_ARGS
1886 INIT_CUMULATIVE_INCOMING_ARGS (all
->args_so_far
, fntype
, NULL_RTX
);
1888 INIT_CUMULATIVE_ARGS (all
->args_so_far
, fntype
, NULL_RTX
,
1889 current_function_decl
, -1);
1892 #ifdef REG_PARM_STACK_SPACE
1893 all
->reg_parm_stack_space
= REG_PARM_STACK_SPACE (current_function_decl
);
1897 /* If ARGS contains entries with complex types, split the entry into two
1898 entries of the component type. Return a new list of substitutions are
1899 needed, else the old list. */
1902 split_complex_args (tree args
)
1906 /* Before allocating memory, check for the common case of no complex. */
1907 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1909 tree type
= TREE_TYPE (p
);
1910 if (TREE_CODE (type
) == COMPLEX_TYPE
1911 && targetm
.calls
.split_complex_arg (type
))
1917 args
= copy_list (args
);
1919 for (p
= args
; p
; p
= TREE_CHAIN (p
))
1921 tree type
= TREE_TYPE (p
);
1922 if (TREE_CODE (type
) == COMPLEX_TYPE
1923 && targetm
.calls
.split_complex_arg (type
))
1926 tree subtype
= TREE_TYPE (type
);
1927 bool addressable
= TREE_ADDRESSABLE (p
);
1929 /* Rewrite the PARM_DECL's type with its component. */
1930 TREE_TYPE (p
) = subtype
;
1931 DECL_ARG_TYPE (p
) = TREE_TYPE (DECL_ARG_TYPE (p
));
1932 DECL_MODE (p
) = VOIDmode
;
1933 DECL_SIZE (p
) = NULL
;
1934 DECL_SIZE_UNIT (p
) = NULL
;
1935 /* If this arg must go in memory, put it in a pseudo here.
1936 We can't allow it to go in memory as per normal parms,
1937 because the usual place might not have the imag part
1938 adjacent to the real part. */
1939 DECL_ARTIFICIAL (p
) = addressable
;
1940 DECL_IGNORED_P (p
) = addressable
;
1941 TREE_ADDRESSABLE (p
) = 0;
1944 /* Build a second synthetic decl. */
1945 decl
= build_decl (PARM_DECL
, NULL_TREE
, subtype
);
1946 DECL_ARG_TYPE (decl
) = DECL_ARG_TYPE (p
);
1947 DECL_ARTIFICIAL (decl
) = addressable
;
1948 DECL_IGNORED_P (decl
) = addressable
;
1949 layout_decl (decl
, 0);
1951 /* Splice it in; skip the new decl. */
1952 TREE_CHAIN (decl
) = TREE_CHAIN (p
);
1953 TREE_CHAIN (p
) = decl
;
1961 /* A subroutine of assign_parms. Adjust the parameter list to incorporate
1962 the hidden struct return argument, and (abi willing) complex args.
1963 Return the new parameter list. */
1966 assign_parms_augmented_arg_list (struct assign_parm_data_all
*all
)
1968 tree fndecl
= current_function_decl
;
1969 tree fntype
= TREE_TYPE (fndecl
);
1970 tree fnargs
= DECL_ARGUMENTS (fndecl
);
1972 /* If struct value address is treated as the first argument, make it so. */
1973 if (aggregate_value_p (DECL_RESULT (fndecl
), fndecl
)
1974 && ! cfun
->returns_pcc_struct
1975 && targetm
.calls
.struct_value_rtx (TREE_TYPE (fndecl
), 1) == 0)
1977 tree type
= build_pointer_type (TREE_TYPE (fntype
));
1980 decl
= build_decl (PARM_DECL
, NULL_TREE
, type
);
1981 DECL_ARG_TYPE (decl
) = type
;
1982 DECL_ARTIFICIAL (decl
) = 1;
1983 DECL_IGNORED_P (decl
) = 1;
1985 TREE_CHAIN (decl
) = fnargs
;
1987 all
->function_result_decl
= decl
;
1990 all
->orig_fnargs
= fnargs
;
1992 /* If the target wants to split complex arguments into scalars, do so. */
1993 if (targetm
.calls
.split_complex_arg
)
1994 fnargs
= split_complex_args (fnargs
);
1999 /* A subroutine of assign_parms. Examine PARM and pull out type and mode
2000 data for the parameter. Incorporate ABI specifics such as pass-by-
2001 reference and type promotion. */
2004 assign_parm_find_data_types (struct assign_parm_data_all
*all
, tree parm
,
2005 struct assign_parm_data_one
*data
)
2007 tree nominal_type
, passed_type
;
2008 enum machine_mode nominal_mode
, passed_mode
, promoted_mode
;
2010 memset (data
, 0, sizeof (*data
));
2012 /* NAMED_ARG is a misnomer. We really mean 'non-variadic'. */
2014 data
->named_arg
= 1; /* No variadic parms. */
2015 else if (TREE_CHAIN (parm
))
2016 data
->named_arg
= 1; /* Not the last non-variadic parm. */
2017 else if (targetm
.calls
.strict_argument_naming (&all
->args_so_far
))
2018 data
->named_arg
= 1; /* Only variadic ones are unnamed. */
2020 data
->named_arg
= 0; /* Treat as variadic. */
2022 nominal_type
= TREE_TYPE (parm
);
2023 passed_type
= DECL_ARG_TYPE (parm
);
2025 /* Look out for errors propagating this far. Also, if the parameter's
2026 type is void then its value doesn't matter. */
2027 if (TREE_TYPE (parm
) == error_mark_node
2028 /* This can happen after weird syntax errors
2029 or if an enum type is defined among the parms. */
2030 || TREE_CODE (parm
) != PARM_DECL
2031 || passed_type
== NULL
2032 || VOID_TYPE_P (nominal_type
))
2034 nominal_type
= passed_type
= void_type_node
;
2035 nominal_mode
= passed_mode
= promoted_mode
= VOIDmode
;
2039 /* Find mode of arg as it is passed, and mode of arg as it should be
2040 during execution of this function. */
2041 passed_mode
= TYPE_MODE (passed_type
);
2042 nominal_mode
= TYPE_MODE (nominal_type
);
2044 /* If the parm is to be passed as a transparent union, use the type of
2045 the first field for the tests below. We have already verified that
2046 the modes are the same. */
2047 if (TREE_CODE (passed_type
) == UNION_TYPE
2048 && TYPE_TRANSPARENT_UNION (passed_type
))
2049 passed_type
= TREE_TYPE (TYPE_FIELDS (passed_type
));
2051 /* See if this arg was passed by invisible reference. */
2052 if (pass_by_reference (&all
->args_so_far
, passed_mode
,
2053 passed_type
, data
->named_arg
))
2055 passed_type
= nominal_type
= build_pointer_type (passed_type
);
2056 data
->passed_pointer
= true;
2057 passed_mode
= nominal_mode
= Pmode
;
2060 /* Find mode as it is passed by the ABI. */
2061 promoted_mode
= passed_mode
;
2062 if (targetm
.calls
.promote_function_args (TREE_TYPE (current_function_decl
)))
2064 int unsignedp
= TYPE_UNSIGNED (passed_type
);
2065 promoted_mode
= promote_mode (passed_type
, promoted_mode
,
2070 data
->nominal_type
= nominal_type
;
2071 data
->passed_type
= passed_type
;
2072 data
->nominal_mode
= nominal_mode
;
2073 data
->passed_mode
= passed_mode
;
2074 data
->promoted_mode
= promoted_mode
;
2077 /* A subroutine of assign_parms. Invoke setup_incoming_varargs. */
2080 assign_parms_setup_varargs (struct assign_parm_data_all
*all
,
2081 struct assign_parm_data_one
*data
, bool no_rtl
)
2083 int varargs_pretend_bytes
= 0;
2085 targetm
.calls
.setup_incoming_varargs (&all
->args_so_far
,
2086 data
->promoted_mode
,
2088 &varargs_pretend_bytes
, no_rtl
);
2090 /* If the back-end has requested extra stack space, record how much is
2091 needed. Do not change pretend_args_size otherwise since it may be
2092 nonzero from an earlier partial argument. */
2093 if (varargs_pretend_bytes
> 0)
2094 all
->pretend_args_size
= varargs_pretend_bytes
;
2097 /* A subroutine of assign_parms. Set DATA->ENTRY_PARM corresponding to
2098 the incoming location of the current parameter. */
2101 assign_parm_find_entry_rtl (struct assign_parm_data_all
*all
,
2102 struct assign_parm_data_one
*data
)
2104 HOST_WIDE_INT pretend_bytes
= 0;
2108 if (data
->promoted_mode
== VOIDmode
)
2110 data
->entry_parm
= data
->stack_parm
= const0_rtx
;
2114 #ifdef FUNCTION_INCOMING_ARG
2115 entry_parm
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2116 data
->passed_type
, data
->named_arg
);
2118 entry_parm
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2119 data
->passed_type
, data
->named_arg
);
2122 if (entry_parm
== 0)
2123 data
->promoted_mode
= data
->passed_mode
;
2125 /* Determine parm's home in the stack, in case it arrives in the stack
2126 or we should pretend it did. Compute the stack position and rtx where
2127 the argument arrives and its size.
2129 There is one complexity here: If this was a parameter that would
2130 have been passed in registers, but wasn't only because it is
2131 __builtin_va_alist, we want locate_and_pad_parm to treat it as if
2132 it came in a register so that REG_PARM_STACK_SPACE isn't skipped.
2133 In this case, we call FUNCTION_ARG with NAMED set to 1 instead of 0
2134 as it was the previous time. */
2135 in_regs
= entry_parm
!= 0;
2136 #ifdef STACK_PARMS_IN_REG_PARM_AREA
2139 if (!in_regs
&& !data
->named_arg
)
2141 if (targetm
.calls
.pretend_outgoing_varargs_named (&all
->args_so_far
))
2144 #ifdef FUNCTION_INCOMING_ARG
2145 tem
= FUNCTION_INCOMING_ARG (all
->args_so_far
, data
->promoted_mode
,
2146 data
->passed_type
, true);
2148 tem
= FUNCTION_ARG (all
->args_so_far
, data
->promoted_mode
,
2149 data
->passed_type
, true);
2151 in_regs
= tem
!= NULL
;
2155 /* If this parameter was passed both in registers and in the stack, use
2156 the copy on the stack. */
2157 if (targetm
.calls
.must_pass_in_stack (data
->promoted_mode
,
2165 partial
= targetm
.calls
.arg_partial_bytes (&all
->args_so_far
,
2166 data
->promoted_mode
,
2169 data
->partial
= partial
;
2171 /* The caller might already have allocated stack space for the
2172 register parameters. */
2173 if (partial
!= 0 && all
->reg_parm_stack_space
== 0)
2175 /* Part of this argument is passed in registers and part
2176 is passed on the stack. Ask the prologue code to extend
2177 the stack part so that we can recreate the full value.
2179 PRETEND_BYTES is the size of the registers we need to store.
2180 CURRENT_FUNCTION_PRETEND_ARGS_SIZE is the amount of extra
2181 stack space that the prologue should allocate.
2183 Internally, gcc assumes that the argument pointer is aligned
2184 to STACK_BOUNDARY bits. This is used both for alignment
2185 optimizations (see init_emit) and to locate arguments that are
2186 aligned to more than PARM_BOUNDARY bits. We must preserve this
2187 invariant by rounding CURRENT_FUNCTION_PRETEND_ARGS_SIZE up to
2188 a stack boundary. */
2190 /* We assume at most one partial arg, and it must be the first
2191 argument on the stack. */
2192 gcc_assert (!all
->extra_pretend_bytes
&& !all
->pretend_args_size
);
2194 pretend_bytes
= partial
;
2195 all
->pretend_args_size
= CEIL_ROUND (pretend_bytes
, STACK_BYTES
);
2197 /* We want to align relative to the actual stack pointer, so
2198 don't include this in the stack size until later. */
2199 all
->extra_pretend_bytes
= all
->pretend_args_size
;
2203 locate_and_pad_parm (data
->promoted_mode
, data
->passed_type
, in_regs
,
2204 entry_parm
? data
->partial
: 0, current_function_decl
,
2205 &all
->stack_args_size
, &data
->locate
);
2207 /* Adjust offsets to include the pretend args. */
2208 pretend_bytes
= all
->extra_pretend_bytes
- pretend_bytes
;
2209 data
->locate
.slot_offset
.constant
+= pretend_bytes
;
2210 data
->locate
.offset
.constant
+= pretend_bytes
;
2212 data
->entry_parm
= entry_parm
;
2215 /* A subroutine of assign_parms. If there is actually space on the stack
2216 for this parm, count it in stack_args_size and return true. */
2219 assign_parm_is_stack_parm (struct assign_parm_data_all
*all
,
2220 struct assign_parm_data_one
*data
)
2222 /* Trivially true if we've no incoming register. */
2223 if (data
->entry_parm
== NULL
)
2225 /* Also true if we're partially in registers and partially not,
2226 since we've arranged to drop the entire argument on the stack. */
2227 else if (data
->partial
!= 0)
2229 /* Also true if the target says that it's passed in both registers
2230 and on the stack. */
2231 else if (GET_CODE (data
->entry_parm
) == PARALLEL
2232 && XEXP (XVECEXP (data
->entry_parm
, 0, 0), 0) == NULL_RTX
)
2234 /* Also true if the target says that there's stack allocated for
2235 all register parameters. */
2236 else if (all
->reg_parm_stack_space
> 0)
2238 /* Otherwise, no, this parameter has no ABI defined stack slot. */
2242 all
->stack_args_size
.constant
+= data
->locate
.size
.constant
;
2243 if (data
->locate
.size
.var
)
2244 ADD_PARM_SIZE (all
->stack_args_size
, data
->locate
.size
.var
);
2249 /* A subroutine of assign_parms. Given that this parameter is allocated
2250 stack space by the ABI, find it. */
2253 assign_parm_find_stack_rtl (tree parm
, struct assign_parm_data_one
*data
)
2255 rtx offset_rtx
, stack_parm
;
2256 unsigned int align
, boundary
;
2258 /* If we're passing this arg using a reg, make its stack home the
2259 aligned stack slot. */
2260 if (data
->entry_parm
)
2261 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.slot_offset
);
2263 offset_rtx
= ARGS_SIZE_RTX (data
->locate
.offset
);
2265 stack_parm
= crtl
->args
.internal_arg_pointer
;
2266 if (offset_rtx
!= const0_rtx
)
2267 stack_parm
= gen_rtx_PLUS (Pmode
, stack_parm
, offset_rtx
);
2268 stack_parm
= gen_rtx_MEM (data
->promoted_mode
, stack_parm
);
2270 set_mem_attributes (stack_parm
, parm
, 1);
2272 boundary
= data
->locate
.boundary
;
2273 align
= BITS_PER_UNIT
;
2275 /* If we're padding upward, we know that the alignment of the slot
2276 is FUNCTION_ARG_BOUNDARY. If we're using slot_offset, we're
2277 intentionally forcing upward padding. Otherwise we have to come
2278 up with a guess at the alignment based on OFFSET_RTX. */
2279 if (data
->locate
.where_pad
!= downward
|| data
->entry_parm
)
2281 else if (GET_CODE (offset_rtx
) == CONST_INT
)
2283 align
= INTVAL (offset_rtx
) * BITS_PER_UNIT
| boundary
;
2284 align
= align
& -align
;
2286 set_mem_align (stack_parm
, align
);
2288 if (data
->entry_parm
)
2289 set_reg_attrs_for_parm (data
->entry_parm
, stack_parm
);
2291 data
->stack_parm
= stack_parm
;
2294 /* A subroutine of assign_parms. Adjust DATA->ENTRY_RTL such that it's
2295 always valid and contiguous. */
2298 assign_parm_adjust_entry_rtl (struct assign_parm_data_one
*data
)
2300 rtx entry_parm
= data
->entry_parm
;
2301 rtx stack_parm
= data
->stack_parm
;
2303 /* If this parm was passed part in regs and part in memory, pretend it
2304 arrived entirely in memory by pushing the register-part onto the stack.
2305 In the special case of a DImode or DFmode that is split, we could put
2306 it together in a pseudoreg directly, but for now that's not worth
2308 if (data
->partial
!= 0)
2310 /* Handle calls that pass values in multiple non-contiguous
2311 locations. The Irix 6 ABI has examples of this. */
2312 if (GET_CODE (entry_parm
) == PARALLEL
)
2313 emit_group_store (validize_mem (stack_parm
), entry_parm
,
2315 int_size_in_bytes (data
->passed_type
));
2318 gcc_assert (data
->partial
% UNITS_PER_WORD
== 0);
2319 move_block_from_reg (REGNO (entry_parm
), validize_mem (stack_parm
),
2320 data
->partial
/ UNITS_PER_WORD
);
2323 entry_parm
= stack_parm
;
2326 /* If we didn't decide this parm came in a register, by default it came
2328 else if (entry_parm
== NULL
)
2329 entry_parm
= stack_parm
;
2331 /* When an argument is passed in multiple locations, we can't make use
2332 of this information, but we can save some copying if the whole argument
2333 is passed in a single register. */
2334 else if (GET_CODE (entry_parm
) == PARALLEL
2335 && data
->nominal_mode
!= BLKmode
2336 && data
->passed_mode
!= BLKmode
)
2338 size_t i
, len
= XVECLEN (entry_parm
, 0);
2340 for (i
= 0; i
< len
; i
++)
2341 if (XEXP (XVECEXP (entry_parm
, 0, i
), 0) != NULL_RTX
2342 && REG_P (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2343 && (GET_MODE (XEXP (XVECEXP (entry_parm
, 0, i
), 0))
2344 == data
->passed_mode
)
2345 && INTVAL (XEXP (XVECEXP (entry_parm
, 0, i
), 1)) == 0)
2347 entry_parm
= XEXP (XVECEXP (entry_parm
, 0, i
), 0);
2352 data
->entry_parm
= entry_parm
;
2355 /* A subroutine of assign_parms. Reconstitute any values which were
2356 passed in multiple registers and would fit in a single register. */
2359 assign_parm_remove_parallels (struct assign_parm_data_one
*data
)
2361 rtx entry_parm
= data
->entry_parm
;
2363 /* Convert the PARALLEL to a REG of the same mode as the parallel.
2364 This can be done with register operations rather than on the
2365 stack, even if we will store the reconstituted parameter on the
2367 if (GET_CODE (entry_parm
) == PARALLEL
&& GET_MODE (entry_parm
) != BLKmode
)
2369 rtx parmreg
= gen_reg_rtx (GET_MODE (entry_parm
));
2370 emit_group_store (parmreg
, entry_parm
, NULL_TREE
,
2371 GET_MODE_SIZE (GET_MODE (entry_parm
)));
2372 entry_parm
= parmreg
;
2375 data
->entry_parm
= entry_parm
;
2378 /* A subroutine of assign_parms. Adjust DATA->STACK_RTL such that it's
2379 always valid and properly aligned. */
2382 assign_parm_adjust_stack_rtl (struct assign_parm_data_one
*data
)
2384 rtx stack_parm
= data
->stack_parm
;
2386 /* If we can't trust the parm stack slot to be aligned enough for its
2387 ultimate type, don't use that slot after entry. We'll make another
2388 stack slot, if we need one. */
2390 && ((STRICT_ALIGNMENT
2391 && GET_MODE_ALIGNMENT (data
->nominal_mode
) > MEM_ALIGN (stack_parm
))
2392 || (data
->nominal_type
2393 && TYPE_ALIGN (data
->nominal_type
) > MEM_ALIGN (stack_parm
)
2394 && MEM_ALIGN (stack_parm
) < PREFERRED_STACK_BOUNDARY
)))
2397 /* If parm was passed in memory, and we need to convert it on entry,
2398 don't store it back in that same slot. */
2399 else if (data
->entry_parm
== stack_parm
2400 && data
->nominal_mode
!= BLKmode
2401 && data
->nominal_mode
!= data
->passed_mode
)
2404 /* If stack protection is in effect for this function, don't leave any
2405 pointers in their passed stack slots. */
2406 else if (crtl
->stack_protect_guard
2407 && (flag_stack_protect
== 2
2408 || data
->passed_pointer
2409 || POINTER_TYPE_P (data
->nominal_type
)))
2412 data
->stack_parm
= stack_parm
;
2415 /* A subroutine of assign_parms. Return true if the current parameter
2416 should be stored as a BLKmode in the current frame. */
2419 assign_parm_setup_block_p (struct assign_parm_data_one
*data
)
2421 if (data
->nominal_mode
== BLKmode
)
2423 if (GET_MODE (data
->entry_parm
) == BLKmode
)
2426 #ifdef BLOCK_REG_PADDING
2427 /* Only assign_parm_setup_block knows how to deal with register arguments
2428 that are padded at the least significant end. */
2429 if (REG_P (data
->entry_parm
)
2430 && GET_MODE_SIZE (data
->promoted_mode
) < UNITS_PER_WORD
2431 && (BLOCK_REG_PADDING (data
->passed_mode
, data
->passed_type
, 1)
2432 == (BYTES_BIG_ENDIAN
? upward
: downward
)))
2439 /* A subroutine of assign_parms. Arrange for the parameter to be
2440 present and valid in DATA->STACK_RTL. */
2443 assign_parm_setup_block (struct assign_parm_data_all
*all
,
2444 tree parm
, struct assign_parm_data_one
*data
)
2446 rtx entry_parm
= data
->entry_parm
;
2447 rtx stack_parm
= data
->stack_parm
;
2449 HOST_WIDE_INT size_stored
;
2451 if (GET_CODE (entry_parm
) == PARALLEL
)
2452 entry_parm
= emit_group_move_into_temps (entry_parm
);
2454 size
= int_size_in_bytes (data
->passed_type
);
2455 size_stored
= CEIL_ROUND (size
, UNITS_PER_WORD
);
2456 if (stack_parm
== 0)
2458 DECL_ALIGN (parm
) = MAX (DECL_ALIGN (parm
), BITS_PER_WORD
);
2459 stack_parm
= assign_stack_local (BLKmode
, size_stored
,
2461 if (GET_MODE_SIZE (GET_MODE (entry_parm
)) == size
)
2462 PUT_MODE (stack_parm
, GET_MODE (entry_parm
));
2463 set_mem_attributes (stack_parm
, parm
, 1);
2466 /* If a BLKmode arrives in registers, copy it to a stack slot. Handle
2467 calls that pass values in multiple non-contiguous locations. */
2468 if (REG_P (entry_parm
) || GET_CODE (entry_parm
) == PARALLEL
)
2472 /* Note that we will be storing an integral number of words.
2473 So we have to be careful to ensure that we allocate an
2474 integral number of words. We do this above when we call
2475 assign_stack_local if space was not allocated in the argument
2476 list. If it was, this will not work if PARM_BOUNDARY is not
2477 a multiple of BITS_PER_WORD. It isn't clear how to fix this
2478 if it becomes a problem. Exception is when BLKmode arrives
2479 with arguments not conforming to word_mode. */
2481 if (data
->stack_parm
== 0)
2483 else if (GET_CODE (entry_parm
) == PARALLEL
)
2486 gcc_assert (!size
|| !(PARM_BOUNDARY
% BITS_PER_WORD
));
2488 mem
= validize_mem (stack_parm
);
2490 /* Handle values in multiple non-contiguous locations. */
2491 if (GET_CODE (entry_parm
) == PARALLEL
)
2493 push_to_sequence2 (all
->first_conversion_insn
,
2494 all
->last_conversion_insn
);
2495 emit_group_store (mem
, entry_parm
, data
->passed_type
, size
);
2496 all
->first_conversion_insn
= get_insns ();
2497 all
->last_conversion_insn
= get_last_insn ();
2504 /* If SIZE is that of a mode no bigger than a word, just use
2505 that mode's store operation. */
2506 else if (size
<= UNITS_PER_WORD
)
2508 enum machine_mode mode
2509 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
2512 #ifdef BLOCK_REG_PADDING
2513 && (size
== UNITS_PER_WORD
2514 || (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2515 != (BYTES_BIG_ENDIAN
? upward
: downward
)))
2521 /* We are really truncating a word_mode value containing
2522 SIZE bytes into a value of mode MODE. If such an
2523 operation requires no actual instructions, we can refer
2524 to the value directly in mode MODE, otherwise we must
2525 start with the register in word_mode and explicitly
2527 if (TRULY_NOOP_TRUNCATION (size
* BITS_PER_UNIT
, BITS_PER_WORD
))
2528 reg
= gen_rtx_REG (mode
, REGNO (entry_parm
));
2531 reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2532 reg
= convert_to_mode (mode
, copy_to_reg (reg
), 1);
2534 emit_move_insn (change_address (mem
, mode
, 0), reg
);
2537 /* Blocks smaller than a word on a BYTES_BIG_ENDIAN
2538 machine must be aligned to the left before storing
2539 to memory. Note that the previous test doesn't
2540 handle all cases (e.g. SIZE == 3). */
2541 else if (size
!= UNITS_PER_WORD
2542 #ifdef BLOCK_REG_PADDING
2543 && (BLOCK_REG_PADDING (mode
, data
->passed_type
, 1)
2551 int by
= (UNITS_PER_WORD
- size
) * BITS_PER_UNIT
;
2552 rtx reg
= gen_rtx_REG (word_mode
, REGNO (entry_parm
));
2554 x
= expand_shift (LSHIFT_EXPR
, word_mode
, reg
,
2555 build_int_cst (NULL_TREE
, by
),
2557 tem
= change_address (mem
, word_mode
, 0);
2558 emit_move_insn (tem
, x
);
2561 move_block_from_reg (REGNO (entry_parm
), mem
,
2562 size_stored
/ UNITS_PER_WORD
);
2565 move_block_from_reg (REGNO (entry_parm
), mem
,
2566 size_stored
/ UNITS_PER_WORD
);
2568 else if (data
->stack_parm
== 0)
2570 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2571 emit_block_move (stack_parm
, data
->entry_parm
, GEN_INT (size
),
2573 all
->first_conversion_insn
= get_insns ();
2574 all
->last_conversion_insn
= get_last_insn ();
2578 data
->stack_parm
= stack_parm
;
2579 SET_DECL_RTL (parm
, stack_parm
);
2582 /* A subroutine of assign_parms. Allocate a pseudo to hold the current
2583 parameter. Get it there. Perform all ABI specified conversions. */
2586 assign_parm_setup_reg (struct assign_parm_data_all
*all
, tree parm
,
2587 struct assign_parm_data_one
*data
)
2590 enum machine_mode promoted_nominal_mode
;
2591 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2592 bool did_conversion
= false;
2594 /* Store the parm in a pseudoregister during the function, but we may
2595 need to do it in a wider mode. */
2597 /* This is not really promoting for a call. However we need to be
2598 consistent with assign_parm_find_data_types and expand_expr_real_1. */
2599 promoted_nominal_mode
2600 = promote_mode (data
->nominal_type
, data
->nominal_mode
, &unsignedp
, 1);
2602 parmreg
= gen_reg_rtx (promoted_nominal_mode
);
2604 if (!DECL_ARTIFICIAL (parm
))
2605 mark_user_reg (parmreg
);
2607 /* If this was an item that we received a pointer to,
2608 set DECL_RTL appropriately. */
2609 if (data
->passed_pointer
)
2611 rtx x
= gen_rtx_MEM (TYPE_MODE (TREE_TYPE (data
->passed_type
)), parmreg
);
2612 set_mem_attributes (x
, parm
, 1);
2613 SET_DECL_RTL (parm
, x
);
2616 SET_DECL_RTL (parm
, parmreg
);
2618 assign_parm_remove_parallels (data
);
2620 /* Copy the value into the register. */
2621 if (data
->nominal_mode
!= data
->passed_mode
2622 || promoted_nominal_mode
!= data
->promoted_mode
)
2626 /* ENTRY_PARM has been converted to PROMOTED_MODE, its
2627 mode, by the caller. We now have to convert it to
2628 NOMINAL_MODE, if different. However, PARMREG may be in
2629 a different mode than NOMINAL_MODE if it is being stored
2632 If ENTRY_PARM is a hard register, it might be in a register
2633 not valid for operating in its mode (e.g., an odd-numbered
2634 register for a DFmode). In that case, moves are the only
2635 thing valid, so we can't do a convert from there. This
2636 occurs when the calling sequence allow such misaligned
2639 In addition, the conversion may involve a call, which could
2640 clobber parameters which haven't been copied to pseudo
2641 registers yet. Therefore, we must first copy the parm to
2642 a pseudo reg here, and save the conversion until after all
2643 parameters have been moved. */
2645 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2647 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2649 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2650 tempreg
= convert_to_mode (data
->nominal_mode
, tempreg
, unsignedp
);
2652 if (GET_CODE (tempreg
) == SUBREG
2653 && GET_MODE (tempreg
) == data
->nominal_mode
2654 && REG_P (SUBREG_REG (tempreg
))
2655 && data
->nominal_mode
== data
->passed_mode
2656 && GET_MODE (SUBREG_REG (tempreg
)) == GET_MODE (data
->entry_parm
)
2657 && GET_MODE_SIZE (GET_MODE (tempreg
))
2658 < GET_MODE_SIZE (GET_MODE (data
->entry_parm
)))
2660 /* The argument is already sign/zero extended, so note it
2662 SUBREG_PROMOTED_VAR_P (tempreg
) = 1;
2663 SUBREG_PROMOTED_UNSIGNED_SET (tempreg
, unsignedp
);
2666 /* TREE_USED gets set erroneously during expand_assignment. */
2667 save_tree_used
= TREE_USED (parm
);
2668 expand_assignment (parm
, make_tree (data
->nominal_type
, tempreg
), false);
2669 TREE_USED (parm
) = save_tree_used
;
2670 all
->first_conversion_insn
= get_insns ();
2671 all
->last_conversion_insn
= get_last_insn ();
2674 did_conversion
= true;
2677 emit_move_insn (parmreg
, validize_mem (data
->entry_parm
));
2679 /* If we were passed a pointer but the actual value can safely live
2680 in a register, put it in one. */
2681 if (data
->passed_pointer
2682 && TYPE_MODE (TREE_TYPE (parm
)) != BLKmode
2683 /* If by-reference argument was promoted, demote it. */
2684 && (TYPE_MODE (TREE_TYPE (parm
)) != GET_MODE (DECL_RTL (parm
))
2685 || use_register_for_decl (parm
)))
2687 /* We can't use nominal_mode, because it will have been set to
2688 Pmode above. We must use the actual mode of the parm. */
2689 parmreg
= gen_reg_rtx (TYPE_MODE (TREE_TYPE (parm
)));
2690 mark_user_reg (parmreg
);
2692 if (GET_MODE (parmreg
) != GET_MODE (DECL_RTL (parm
)))
2694 rtx tempreg
= gen_reg_rtx (GET_MODE (DECL_RTL (parm
)));
2695 int unsigned_p
= TYPE_UNSIGNED (TREE_TYPE (parm
));
2697 push_to_sequence2 (all
->first_conversion_insn
,
2698 all
->last_conversion_insn
);
2699 emit_move_insn (tempreg
, DECL_RTL (parm
));
2700 tempreg
= convert_to_mode (GET_MODE (parmreg
), tempreg
, unsigned_p
);
2701 emit_move_insn (parmreg
, tempreg
);
2702 all
->first_conversion_insn
= get_insns ();
2703 all
->last_conversion_insn
= get_last_insn ();
2706 did_conversion
= true;
2709 emit_move_insn (parmreg
, DECL_RTL (parm
));
2711 SET_DECL_RTL (parm
, parmreg
);
2713 /* STACK_PARM is the pointer, not the parm, and PARMREG is
2715 data
->stack_parm
= NULL
;
2718 /* Mark the register as eliminable if we did no conversion and it was
2719 copied from memory at a fixed offset, and the arg pointer was not
2720 copied to a pseudo-reg. If the arg pointer is a pseudo reg or the
2721 offset formed an invalid address, such memory-equivalences as we
2722 make here would screw up life analysis for it. */
2723 if (data
->nominal_mode
== data
->passed_mode
2725 && data
->stack_parm
!= 0
2726 && MEM_P (data
->stack_parm
)
2727 && data
->locate
.offset
.var
== 0
2728 && reg_mentioned_p (virtual_incoming_args_rtx
,
2729 XEXP (data
->stack_parm
, 0)))
2731 rtx linsn
= get_last_insn ();
2734 /* Mark complex types separately. */
2735 if (GET_CODE (parmreg
) == CONCAT
)
2737 enum machine_mode submode
2738 = GET_MODE_INNER (GET_MODE (parmreg
));
2739 int regnor
= REGNO (XEXP (parmreg
, 0));
2740 int regnoi
= REGNO (XEXP (parmreg
, 1));
2741 rtx stackr
= adjust_address_nv (data
->stack_parm
, submode
, 0);
2742 rtx stacki
= adjust_address_nv (data
->stack_parm
, submode
,
2743 GET_MODE_SIZE (submode
));
2745 /* Scan backwards for the set of the real and
2747 for (sinsn
= linsn
; sinsn
!= 0;
2748 sinsn
= prev_nonnote_insn (sinsn
))
2750 set
= single_set (sinsn
);
2754 if (SET_DEST (set
) == regno_reg_rtx
[regnoi
])
2755 set_unique_reg_note (sinsn
, REG_EQUIV
, stacki
);
2756 else if (SET_DEST (set
) == regno_reg_rtx
[regnor
])
2757 set_unique_reg_note (sinsn
, REG_EQUIV
, stackr
);
2760 else if ((set
= single_set (linsn
)) != 0
2761 && SET_DEST (set
) == parmreg
)
2762 set_unique_reg_note (linsn
, REG_EQUIV
, data
->stack_parm
);
2765 /* For pointer data type, suggest pointer register. */
2766 if (POINTER_TYPE_P (TREE_TYPE (parm
)))
2767 mark_reg_pointer (parmreg
,
2768 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
2771 /* A subroutine of assign_parms. Allocate stack space to hold the current
2772 parameter. Get it there. Perform all ABI specified conversions. */
2775 assign_parm_setup_stack (struct assign_parm_data_all
*all
, tree parm
,
2776 struct assign_parm_data_one
*data
)
2778 /* Value must be stored in the stack slot STACK_PARM during function
2780 bool to_conversion
= false;
2782 assign_parm_remove_parallels (data
);
2784 if (data
->promoted_mode
!= data
->nominal_mode
)
2786 /* Conversion is required. */
2787 rtx tempreg
= gen_reg_rtx (GET_MODE (data
->entry_parm
));
2789 emit_move_insn (tempreg
, validize_mem (data
->entry_parm
));
2791 push_to_sequence2 (all
->first_conversion_insn
, all
->last_conversion_insn
);
2792 to_conversion
= true;
2794 data
->entry_parm
= convert_to_mode (data
->nominal_mode
, tempreg
,
2795 TYPE_UNSIGNED (TREE_TYPE (parm
)));
2797 if (data
->stack_parm
)
2798 /* ??? This may need a big-endian conversion on sparc64. */
2800 = adjust_address (data
->stack_parm
, data
->nominal_mode
, 0);
2803 if (data
->entry_parm
!= data
->stack_parm
)
2807 if (data
->stack_parm
== 0)
2810 = assign_stack_local (GET_MODE (data
->entry_parm
),
2811 GET_MODE_SIZE (GET_MODE (data
->entry_parm
)),
2812 TYPE_ALIGN (data
->passed_type
));
2813 set_mem_attributes (data
->stack_parm
, parm
, 1);
2816 dest
= validize_mem (data
->stack_parm
);
2817 src
= validize_mem (data
->entry_parm
);
2821 /* Use a block move to handle potentially misaligned entry_parm. */
2823 push_to_sequence2 (all
->first_conversion_insn
,
2824 all
->last_conversion_insn
);
2825 to_conversion
= true;
2827 emit_block_move (dest
, src
,
2828 GEN_INT (int_size_in_bytes (data
->passed_type
)),
2832 emit_move_insn (dest
, src
);
2837 all
->first_conversion_insn
= get_insns ();
2838 all
->last_conversion_insn
= get_last_insn ();
2842 SET_DECL_RTL (parm
, data
->stack_parm
);
2845 /* A subroutine of assign_parms. If the ABI splits complex arguments, then
2846 undo the frobbing that we did in assign_parms_augmented_arg_list. */
2849 assign_parms_unsplit_complex (struct assign_parm_data_all
*all
, tree fnargs
)
2852 tree orig_fnargs
= all
->orig_fnargs
;
2854 for (parm
= orig_fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2856 if (TREE_CODE (TREE_TYPE (parm
)) == COMPLEX_TYPE
2857 && targetm
.calls
.split_complex_arg (TREE_TYPE (parm
)))
2859 rtx tmp
, real
, imag
;
2860 enum machine_mode inner
= GET_MODE_INNER (DECL_MODE (parm
));
2862 real
= DECL_RTL (fnargs
);
2863 imag
= DECL_RTL (TREE_CHAIN (fnargs
));
2864 if (inner
!= GET_MODE (real
))
2866 real
= gen_lowpart_SUBREG (inner
, real
);
2867 imag
= gen_lowpart_SUBREG (inner
, imag
);
2870 if (TREE_ADDRESSABLE (parm
))
2873 HOST_WIDE_INT size
= int_size_in_bytes (TREE_TYPE (parm
));
2875 /* split_complex_arg put the real and imag parts in
2876 pseudos. Move them to memory. */
2877 tmp
= assign_stack_local (DECL_MODE (parm
), size
,
2878 TYPE_ALIGN (TREE_TYPE (parm
)));
2879 set_mem_attributes (tmp
, parm
, 1);
2880 rmem
= adjust_address_nv (tmp
, inner
, 0);
2881 imem
= adjust_address_nv (tmp
, inner
, GET_MODE_SIZE (inner
));
2882 push_to_sequence2 (all
->first_conversion_insn
,
2883 all
->last_conversion_insn
);
2884 emit_move_insn (rmem
, real
);
2885 emit_move_insn (imem
, imag
);
2886 all
->first_conversion_insn
= get_insns ();
2887 all
->last_conversion_insn
= get_last_insn ();
2891 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2892 SET_DECL_RTL (parm
, tmp
);
2894 real
= DECL_INCOMING_RTL (fnargs
);
2895 imag
= DECL_INCOMING_RTL (TREE_CHAIN (fnargs
));
2896 if (inner
!= GET_MODE (real
))
2898 real
= gen_lowpart_SUBREG (inner
, real
);
2899 imag
= gen_lowpart_SUBREG (inner
, imag
);
2901 tmp
= gen_rtx_CONCAT (DECL_MODE (parm
), real
, imag
);
2902 set_decl_incoming_rtl (parm
, tmp
, false);
2903 fnargs
= TREE_CHAIN (fnargs
);
2907 SET_DECL_RTL (parm
, DECL_RTL (fnargs
));
2908 set_decl_incoming_rtl (parm
, DECL_INCOMING_RTL (fnargs
), false);
2910 /* Set MEM_EXPR to the original decl, i.e. to PARM,
2911 instead of the copy of decl, i.e. FNARGS. */
2912 if (DECL_INCOMING_RTL (parm
) && MEM_P (DECL_INCOMING_RTL (parm
)))
2913 set_mem_expr (DECL_INCOMING_RTL (parm
), parm
);
2916 fnargs
= TREE_CHAIN (fnargs
);
2920 /* Assign RTL expressions to the function's parameters. This may involve
2921 copying them into registers and using those registers as the DECL_RTL. */
2924 assign_parms (tree fndecl
)
2926 struct assign_parm_data_all all
;
2929 crtl
->args
.internal_arg_pointer
2930 = targetm
.calls
.internal_arg_pointer ();
2932 assign_parms_initialize_all (&all
);
2933 fnargs
= assign_parms_augmented_arg_list (&all
);
2935 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
2937 struct assign_parm_data_one data
;
2939 /* Extract the type of PARM; adjust it according to ABI. */
2940 assign_parm_find_data_types (&all
, parm
, &data
);
2942 /* Early out for errors and void parameters. */
2943 if (data
.passed_mode
== VOIDmode
)
2945 SET_DECL_RTL (parm
, const0_rtx
);
2946 DECL_INCOMING_RTL (parm
) = DECL_RTL (parm
);
2950 if (cfun
->stdarg
&& !TREE_CHAIN (parm
))
2951 assign_parms_setup_varargs (&all
, &data
, false);
2953 /* Find out where the parameter arrives in this function. */
2954 assign_parm_find_entry_rtl (&all
, &data
);
2956 /* Find out where stack space for this parameter might be. */
2957 if (assign_parm_is_stack_parm (&all
, &data
))
2959 assign_parm_find_stack_rtl (parm
, &data
);
2960 assign_parm_adjust_entry_rtl (&data
);
2963 /* Record permanently how this parm was passed. */
2964 set_decl_incoming_rtl (parm
, data
.entry_parm
, data
.passed_pointer
);
2966 /* Update info on where next arg arrives in registers. */
2967 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
2968 data
.passed_type
, data
.named_arg
);
2970 assign_parm_adjust_stack_rtl (&data
);
2972 if (assign_parm_setup_block_p (&data
))
2973 assign_parm_setup_block (&all
, parm
, &data
);
2974 else if (data
.passed_pointer
|| use_register_for_decl (parm
))
2975 assign_parm_setup_reg (&all
, parm
, &data
);
2977 assign_parm_setup_stack (&all
, parm
, &data
);
2980 if (targetm
.calls
.split_complex_arg
&& fnargs
!= all
.orig_fnargs
)
2981 assign_parms_unsplit_complex (&all
, fnargs
);
2983 /* Output all parameter conversion instructions (possibly including calls)
2984 now that all parameters have been copied out of hard registers. */
2985 emit_insn (all
.first_conversion_insn
);
2987 /* If we are receiving a struct value address as the first argument, set up
2988 the RTL for the function result. As this might require code to convert
2989 the transmitted address to Pmode, we do this here to ensure that possible
2990 preliminary conversions of the address have been emitted already. */
2991 if (all
.function_result_decl
)
2993 tree result
= DECL_RESULT (current_function_decl
);
2994 rtx addr
= DECL_RTL (all
.function_result_decl
);
2997 if (DECL_BY_REFERENCE (result
))
3001 addr
= convert_memory_address (Pmode
, addr
);
3002 x
= gen_rtx_MEM (DECL_MODE (result
), addr
);
3003 set_mem_attributes (x
, result
, 1);
3005 SET_DECL_RTL (result
, x
);
3008 /* We have aligned all the args, so add space for the pretend args. */
3009 crtl
->args
.pretend_args_size
= all
.pretend_args_size
;
3010 all
.stack_args_size
.constant
+= all
.extra_pretend_bytes
;
3011 crtl
->args
.size
= all
.stack_args_size
.constant
;
3013 /* Adjust function incoming argument size for alignment and
3016 #ifdef REG_PARM_STACK_SPACE
3017 crtl
->args
.size
= MAX (crtl
->args
.size
,
3018 REG_PARM_STACK_SPACE (fndecl
));
3021 crtl
->args
.size
= CEIL_ROUND (crtl
->args
.size
,
3022 PARM_BOUNDARY
/ BITS_PER_UNIT
);
3024 #ifdef ARGS_GROW_DOWNWARD
3025 crtl
->args
.arg_offset_rtx
3026 = (all
.stack_args_size
.var
== 0 ? GEN_INT (-all
.stack_args_size
.constant
)
3027 : expand_expr (size_diffop (all
.stack_args_size
.var
,
3028 size_int (-all
.stack_args_size
.constant
)),
3029 NULL_RTX
, VOIDmode
, 0));
3031 crtl
->args
.arg_offset_rtx
= ARGS_SIZE_RTX (all
.stack_args_size
);
3034 /* See how many bytes, if any, of its args a function should try to pop
3037 crtl
->args
.pops_args
= RETURN_POPS_ARGS (fndecl
, TREE_TYPE (fndecl
),
3040 /* For stdarg.h function, save info about
3041 regs and stack space used by the named args. */
3043 crtl
->args
.info
= all
.args_so_far
;
3045 /* Set the rtx used for the function return value. Put this in its
3046 own variable so any optimizers that need this information don't have
3047 to include tree.h. Do this here so it gets done when an inlined
3048 function gets output. */
3051 = (DECL_RTL_SET_P (DECL_RESULT (fndecl
))
3052 ? DECL_RTL (DECL_RESULT (fndecl
)) : NULL_RTX
);
3054 /* If scalar return value was computed in a pseudo-reg, or was a named
3055 return value that got dumped to the stack, copy that to the hard
3057 if (DECL_RTL_SET_P (DECL_RESULT (fndecl
)))
3059 tree decl_result
= DECL_RESULT (fndecl
);
3060 rtx decl_rtl
= DECL_RTL (decl_result
);
3062 if (REG_P (decl_rtl
)
3063 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
3064 : DECL_REGISTER (decl_result
))
3068 real_decl_rtl
= targetm
.calls
.function_value (TREE_TYPE (decl_result
),
3070 REG_FUNCTION_VALUE_P (real_decl_rtl
) = 1;
3071 /* The delay slot scheduler assumes that crtl->return_rtx
3072 holds the hard register containing the return value, not a
3073 temporary pseudo. */
3074 crtl
->return_rtx
= real_decl_rtl
;
3079 /* A subroutine of gimplify_parameters, invoked via walk_tree.
3080 For all seen types, gimplify their sizes. */
3083 gimplify_parm_type (tree
*tp
, int *walk_subtrees
, void *data
)
3090 if (POINTER_TYPE_P (t
))
3092 else if (TYPE_SIZE (t
) && !TREE_CONSTANT (TYPE_SIZE (t
))
3093 && !TYPE_SIZES_GIMPLIFIED (t
))
3095 gimplify_type_sizes (t
, (gimple_seq
*) data
);
3103 /* Gimplify the parameter list for current_function_decl. This involves
3104 evaluating SAVE_EXPRs of variable sized parameters and generating code
3105 to implement callee-copies reference parameters. Returns a sequence of
3106 statements to add to the beginning of the function. */
3109 gimplify_parameters (void)
3111 struct assign_parm_data_all all
;
3113 gimple_seq stmts
= NULL
;
3115 assign_parms_initialize_all (&all
);
3116 fnargs
= assign_parms_augmented_arg_list (&all
);
3118 for (parm
= fnargs
; parm
; parm
= TREE_CHAIN (parm
))
3120 struct assign_parm_data_one data
;
3122 /* Extract the type of PARM; adjust it according to ABI. */
3123 assign_parm_find_data_types (&all
, parm
, &data
);
3125 /* Early out for errors and void parameters. */
3126 if (data
.passed_mode
== VOIDmode
|| DECL_SIZE (parm
) == NULL
)
3129 /* Update info on where next arg arrives in registers. */
3130 FUNCTION_ARG_ADVANCE (all
.args_so_far
, data
.promoted_mode
,
3131 data
.passed_type
, data
.named_arg
);
3133 /* ??? Once upon a time variable_size stuffed parameter list
3134 SAVE_EXPRs (amongst others) onto a pending sizes list. This
3135 turned out to be less than manageable in the gimple world.
3136 Now we have to hunt them down ourselves. */
3137 walk_tree_without_duplicates (&data
.passed_type
,
3138 gimplify_parm_type
, &stmts
);
3140 if (!TREE_CONSTANT (DECL_SIZE (parm
)))
3142 gimplify_one_sizepos (&DECL_SIZE (parm
), &stmts
);
3143 gimplify_one_sizepos (&DECL_SIZE_UNIT (parm
), &stmts
);
3146 if (data
.passed_pointer
)
3148 tree type
= TREE_TYPE (data
.passed_type
);
3149 if (reference_callee_copied (&all
.args_so_far
, TYPE_MODE (type
),
3150 type
, data
.named_arg
))
3154 /* For constant sized objects, this is trivial; for
3155 variable-sized objects, we have to play games. */
3156 if (TREE_CONSTANT (DECL_SIZE (parm
)))
3158 local
= create_tmp_var (type
, get_name (parm
));
3159 DECL_IGNORED_P (local
) = 0;
3163 tree ptr_type
, addr
;
3165 ptr_type
= build_pointer_type (type
);
3166 addr
= create_tmp_var (ptr_type
, get_name (parm
));
3167 DECL_IGNORED_P (addr
) = 0;
3168 local
= build_fold_indirect_ref (addr
);
3170 t
= built_in_decls
[BUILT_IN_ALLOCA
];
3171 t
= build_call_expr (t
, 1, DECL_SIZE_UNIT (parm
));
3172 t
= fold_convert (ptr_type
, t
);
3173 t
= build2 (MODIFY_EXPR
, TREE_TYPE (addr
), addr
, t
);
3174 gimplify_and_add (t
, &stmts
);
3177 gimplify_assign (local
, parm
, &stmts
);
3179 SET_DECL_VALUE_EXPR (parm
, local
);
3180 DECL_HAS_VALUE_EXPR_P (parm
) = 1;
3188 /* Compute the size and offset from the start of the stacked arguments for a
3189 parm passed in mode PASSED_MODE and with type TYPE.
3191 INITIAL_OFFSET_PTR points to the current offset into the stacked
3194 The starting offset and size for this parm are returned in
3195 LOCATE->OFFSET and LOCATE->SIZE, respectively. When IN_REGS is
3196 nonzero, the offset is that of stack slot, which is returned in
3197 LOCATE->SLOT_OFFSET. LOCATE->ALIGNMENT_PAD is the amount of
3198 padding required from the initial offset ptr to the stack slot.
3200 IN_REGS is nonzero if the argument will be passed in registers. It will
3201 never be set if REG_PARM_STACK_SPACE is not defined.
3203 FNDECL is the function in which the argument was defined.
3205 There are two types of rounding that are done. The first, controlled by
3206 FUNCTION_ARG_BOUNDARY, forces the offset from the start of the argument
3207 list to be aligned to the specific boundary (in bits). This rounding
3208 affects the initial and starting offsets, but not the argument size.
3210 The second, controlled by FUNCTION_ARG_PADDING and PARM_BOUNDARY,
3211 optionally rounds the size of the parm to PARM_BOUNDARY. The
3212 initial offset is not affected by this rounding, while the size always
3213 is and the starting offset may be. */
3215 /* LOCATE->OFFSET will be negative for ARGS_GROW_DOWNWARD case;
3216 INITIAL_OFFSET_PTR is positive because locate_and_pad_parm's
3217 callers pass in the total size of args so far as
3218 INITIAL_OFFSET_PTR. LOCATE->SIZE is always positive. */
3221 locate_and_pad_parm (enum machine_mode passed_mode
, tree type
, int in_regs
,
3222 int partial
, tree fndecl ATTRIBUTE_UNUSED
,
3223 struct args_size
*initial_offset_ptr
,
3224 struct locate_and_pad_arg_data
*locate
)
3227 enum direction where_pad
;
3228 unsigned int boundary
;
3229 int reg_parm_stack_space
= 0;
3230 int part_size_in_regs
;
3232 #ifdef REG_PARM_STACK_SPACE
3233 reg_parm_stack_space
= REG_PARM_STACK_SPACE (fndecl
);
3235 /* If we have found a stack parm before we reach the end of the
3236 area reserved for registers, skip that area. */
3239 if (reg_parm_stack_space
> 0)
3241 if (initial_offset_ptr
->var
)
3243 initial_offset_ptr
->var
3244 = size_binop (MAX_EXPR
, ARGS_SIZE_TREE (*initial_offset_ptr
),
3245 ssize_int (reg_parm_stack_space
));
3246 initial_offset_ptr
->constant
= 0;
3248 else if (initial_offset_ptr
->constant
< reg_parm_stack_space
)
3249 initial_offset_ptr
->constant
= reg_parm_stack_space
;
3252 #endif /* REG_PARM_STACK_SPACE */
3254 part_size_in_regs
= (reg_parm_stack_space
== 0 ? partial
: 0);
3257 = type
? size_in_bytes (type
) : size_int (GET_MODE_SIZE (passed_mode
));
3258 where_pad
= FUNCTION_ARG_PADDING (passed_mode
, type
);
3259 boundary
= FUNCTION_ARG_BOUNDARY (passed_mode
, type
);
3260 if (boundary
> PREFERRED_STACK_BOUNDARY
)
3261 boundary
= PREFERRED_STACK_BOUNDARY
;
3262 locate
->where_pad
= where_pad
;
3263 locate
->boundary
= boundary
;
3265 /* Remember if the outgoing parameter requires extra alignment on the
3266 calling function side. */
3267 if (crtl
->stack_alignment_needed
< boundary
)
3268 crtl
->stack_alignment_needed
= boundary
;
3270 #ifdef ARGS_GROW_DOWNWARD
3271 locate
->slot_offset
.constant
= -initial_offset_ptr
->constant
;
3272 if (initial_offset_ptr
->var
)
3273 locate
->slot_offset
.var
= size_binop (MINUS_EXPR
, ssize_int (0),
3274 initial_offset_ptr
->var
);
3278 if (where_pad
!= none
3279 && (!host_integerp (sizetree
, 1)
3280 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3281 s2
= round_up (s2
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3282 SUB_PARM_SIZE (locate
->slot_offset
, s2
);
3285 locate
->slot_offset
.constant
+= part_size_in_regs
;
3288 #ifdef REG_PARM_STACK_SPACE
3289 || REG_PARM_STACK_SPACE (fndecl
) > 0
3292 pad_to_arg_alignment (&locate
->slot_offset
, boundary
,
3293 &locate
->alignment_pad
);
3295 locate
->size
.constant
= (-initial_offset_ptr
->constant
3296 - locate
->slot_offset
.constant
);
3297 if (initial_offset_ptr
->var
)
3298 locate
->size
.var
= size_binop (MINUS_EXPR
,
3299 size_binop (MINUS_EXPR
,
3301 initial_offset_ptr
->var
),
3302 locate
->slot_offset
.var
);
3304 /* Pad_below needs the pre-rounded size to know how much to pad
3306 locate
->offset
= locate
->slot_offset
;
3307 if (where_pad
== downward
)
3308 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3310 #else /* !ARGS_GROW_DOWNWARD */
3312 #ifdef REG_PARM_STACK_SPACE
3313 || REG_PARM_STACK_SPACE (fndecl
) > 0
3316 pad_to_arg_alignment (initial_offset_ptr
, boundary
,
3317 &locate
->alignment_pad
);
3318 locate
->slot_offset
= *initial_offset_ptr
;
3320 #ifdef PUSH_ROUNDING
3321 if (passed_mode
!= BLKmode
)
3322 sizetree
= size_int (PUSH_ROUNDING (TREE_INT_CST_LOW (sizetree
)));
3325 /* Pad_below needs the pre-rounded size to know how much to pad below
3326 so this must be done before rounding up. */
3327 locate
->offset
= locate
->slot_offset
;
3328 if (where_pad
== downward
)
3329 pad_below (&locate
->offset
, passed_mode
, sizetree
);
3331 if (where_pad
!= none
3332 && (!host_integerp (sizetree
, 1)
3333 || (tree_low_cst (sizetree
, 1) * BITS_PER_UNIT
) % PARM_BOUNDARY
))
3334 sizetree
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3336 ADD_PARM_SIZE (locate
->size
, sizetree
);
3338 locate
->size
.constant
-= part_size_in_regs
;
3339 #endif /* ARGS_GROW_DOWNWARD */
3342 /* Round the stack offset in *OFFSET_PTR up to a multiple of BOUNDARY.
3343 BOUNDARY is measured in bits, but must be a multiple of a storage unit. */
3346 pad_to_arg_alignment (struct args_size
*offset_ptr
, int boundary
,
3347 struct args_size
*alignment_pad
)
3349 tree save_var
= NULL_TREE
;
3350 HOST_WIDE_INT save_constant
= 0;
3351 int boundary_in_bytes
= boundary
/ BITS_PER_UNIT
;
3352 HOST_WIDE_INT sp_offset
= STACK_POINTER_OFFSET
;
3354 #ifdef SPARC_STACK_BOUNDARY_HACK
3355 /* ??? The SPARC port may claim a STACK_BOUNDARY higher than
3356 the real alignment of %sp. However, when it does this, the
3357 alignment of %sp+STACK_POINTER_OFFSET is STACK_BOUNDARY. */
3358 if (SPARC_STACK_BOUNDARY_HACK
)
3362 if (boundary
> PARM_BOUNDARY
)
3364 save_var
= offset_ptr
->var
;
3365 save_constant
= offset_ptr
->constant
;
3368 alignment_pad
->var
= NULL_TREE
;
3369 alignment_pad
->constant
= 0;
3371 if (boundary
> BITS_PER_UNIT
)
3373 if (offset_ptr
->var
)
3375 tree sp_offset_tree
= ssize_int (sp_offset
);
3376 tree offset
= size_binop (PLUS_EXPR
,
3377 ARGS_SIZE_TREE (*offset_ptr
),
3379 #ifdef ARGS_GROW_DOWNWARD
3380 tree rounded
= round_down (offset
, boundary
/ BITS_PER_UNIT
);
3382 tree rounded
= round_up (offset
, boundary
/ BITS_PER_UNIT
);
3385 offset_ptr
->var
= size_binop (MINUS_EXPR
, rounded
, sp_offset_tree
);
3386 /* ARGS_SIZE_TREE includes constant term. */
3387 offset_ptr
->constant
= 0;
3388 if (boundary
> PARM_BOUNDARY
)
3389 alignment_pad
->var
= size_binop (MINUS_EXPR
, offset_ptr
->var
,
3394 offset_ptr
->constant
= -sp_offset
+
3395 #ifdef ARGS_GROW_DOWNWARD
3396 FLOOR_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3398 CEIL_ROUND (offset_ptr
->constant
+ sp_offset
, boundary_in_bytes
);
3400 if (boundary
> PARM_BOUNDARY
)
3401 alignment_pad
->constant
= offset_ptr
->constant
- save_constant
;
3407 pad_below (struct args_size
*offset_ptr
, enum machine_mode passed_mode
, tree sizetree
)
3409 if (passed_mode
!= BLKmode
)
3411 if (GET_MODE_BITSIZE (passed_mode
) % PARM_BOUNDARY
)
3412 offset_ptr
->constant
3413 += (((GET_MODE_BITSIZE (passed_mode
) + PARM_BOUNDARY
- 1)
3414 / PARM_BOUNDARY
* PARM_BOUNDARY
/ BITS_PER_UNIT
)
3415 - GET_MODE_SIZE (passed_mode
));
3419 if (TREE_CODE (sizetree
) != INTEGER_CST
3420 || (TREE_INT_CST_LOW (sizetree
) * BITS_PER_UNIT
) % PARM_BOUNDARY
)
3422 /* Round the size up to multiple of PARM_BOUNDARY bits. */
3423 tree s2
= round_up (sizetree
, PARM_BOUNDARY
/ BITS_PER_UNIT
);
3425 ADD_PARM_SIZE (*offset_ptr
, s2
);
3426 SUB_PARM_SIZE (*offset_ptr
, sizetree
);
3432 /* True if register REGNO was alive at a place where `setjmp' was
3433 called and was set more than once or is an argument. Such regs may
3434 be clobbered by `longjmp'. */
3437 regno_clobbered_at_setjmp (bitmap setjmp_crosses
, int regno
)
3439 /* There appear to be cases where some local vars never reach the
3440 backend but have bogus regnos. */
3441 if (regno
>= max_reg_num ())
3444 return ((REG_N_SETS (regno
) > 1
3445 || REGNO_REG_SET_P (df_get_live_out (ENTRY_BLOCK_PTR
), regno
))
3446 && REGNO_REG_SET_P (setjmp_crosses
, regno
));
3449 /* Walk the tree of blocks describing the binding levels within a
3450 function and warn about variables the might be killed by setjmp or
3451 vfork. This is done after calling flow_analysis before register
3452 allocation since that will clobber the pseudo-regs to hard
3456 setjmp_vars_warning (bitmap setjmp_crosses
, tree block
)
3460 for (decl
= BLOCK_VARS (block
); decl
; decl
= TREE_CHAIN (decl
))
3462 if (TREE_CODE (decl
) == VAR_DECL
3463 && DECL_RTL_SET_P (decl
)
3464 && REG_P (DECL_RTL (decl
))
3465 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3466 warning (OPT_Wclobbered
, "variable %q+D might be clobbered by"
3467 " %<longjmp%> or %<vfork%>", decl
);
3470 for (sub
= BLOCK_SUBBLOCKS (block
); sub
; sub
= BLOCK_CHAIN (sub
))
3471 setjmp_vars_warning (setjmp_crosses
, sub
);
3474 /* Do the appropriate part of setjmp_vars_warning
3475 but for arguments instead of local variables. */
3478 setjmp_args_warning (bitmap setjmp_crosses
)
3481 for (decl
= DECL_ARGUMENTS (current_function_decl
);
3482 decl
; decl
= TREE_CHAIN (decl
))
3483 if (DECL_RTL (decl
) != 0
3484 && REG_P (DECL_RTL (decl
))
3485 && regno_clobbered_at_setjmp (setjmp_crosses
, REGNO (DECL_RTL (decl
))))
3486 warning (OPT_Wclobbered
,
3487 "argument %q+D might be clobbered by %<longjmp%> or %<vfork%>",
3491 /* Generate warning messages for variables live across setjmp. */
3494 generate_setjmp_warnings (void)
3496 bitmap setjmp_crosses
= regstat_get_setjmp_crosses ();
3498 if (n_basic_blocks
== NUM_FIXED_BLOCKS
3499 || bitmap_empty_p (setjmp_crosses
))
3502 setjmp_vars_warning (setjmp_crosses
, DECL_INITIAL (current_function_decl
));
3503 setjmp_args_warning (setjmp_crosses
);
3507 /* Identify BLOCKs referenced by more than one NOTE_INSN_BLOCK_{BEG,END},
3508 and create duplicate blocks. */
3509 /* ??? Need an option to either create block fragments or to create
3510 abstract origin duplicates of a source block. It really depends
3511 on what optimization has been performed. */
3514 reorder_blocks (void)
3516 tree block
= DECL_INITIAL (current_function_decl
);
3517 VEC(tree
,heap
) *block_stack
;
3519 if (block
== NULL_TREE
)
3522 block_stack
= VEC_alloc (tree
, heap
, 10);
3524 /* Reset the TREE_ASM_WRITTEN bit for all blocks. */
3525 clear_block_marks (block
);
3527 /* Prune the old trees away, so that they don't get in the way. */
3528 BLOCK_SUBBLOCKS (block
) = NULL_TREE
;
3529 BLOCK_CHAIN (block
) = NULL_TREE
;
3531 /* Recreate the block tree from the note nesting. */
3532 reorder_blocks_1 (get_insns (), block
, &block_stack
);
3533 BLOCK_SUBBLOCKS (block
) = blocks_nreverse (BLOCK_SUBBLOCKS (block
));
3535 VEC_free (tree
, heap
, block_stack
);
3538 /* Helper function for reorder_blocks. Reset TREE_ASM_WRITTEN. */
3541 clear_block_marks (tree block
)
3545 TREE_ASM_WRITTEN (block
) = 0;
3546 clear_block_marks (BLOCK_SUBBLOCKS (block
));
3547 block
= BLOCK_CHAIN (block
);
3552 reorder_blocks_1 (rtx insns
, tree current_block
, VEC(tree
,heap
) **p_block_stack
)
3556 for (insn
= insns
; insn
; insn
= NEXT_INSN (insn
))
3560 if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_BEG
)
3562 tree block
= NOTE_BLOCK (insn
);
3565 origin
= (BLOCK_FRAGMENT_ORIGIN (block
)
3566 ? BLOCK_FRAGMENT_ORIGIN (block
)
3569 /* If we have seen this block before, that means it now
3570 spans multiple address regions. Create a new fragment. */
3571 if (TREE_ASM_WRITTEN (block
))
3573 tree new_block
= copy_node (block
);
3575 BLOCK_FRAGMENT_ORIGIN (new_block
) = origin
;
3576 BLOCK_FRAGMENT_CHAIN (new_block
)
3577 = BLOCK_FRAGMENT_CHAIN (origin
);
3578 BLOCK_FRAGMENT_CHAIN (origin
) = new_block
;
3580 NOTE_BLOCK (insn
) = new_block
;
3584 BLOCK_SUBBLOCKS (block
) = 0;
3585 TREE_ASM_WRITTEN (block
) = 1;
3586 /* When there's only one block for the entire function,
3587 current_block == block and we mustn't do this, it
3588 will cause infinite recursion. */
3589 if (block
!= current_block
)
3591 if (block
!= origin
)
3592 gcc_assert (BLOCK_SUPERCONTEXT (origin
) == current_block
);
3594 BLOCK_SUPERCONTEXT (block
) = current_block
;
3595 BLOCK_CHAIN (block
) = BLOCK_SUBBLOCKS (current_block
);
3596 BLOCK_SUBBLOCKS (current_block
) = block
;
3597 current_block
= origin
;
3599 VEC_safe_push (tree
, heap
, *p_block_stack
, block
);
3601 else if (NOTE_KIND (insn
) == NOTE_INSN_BLOCK_END
)
3603 NOTE_BLOCK (insn
) = VEC_pop (tree
, *p_block_stack
);
3604 BLOCK_SUBBLOCKS (current_block
)
3605 = blocks_nreverse (BLOCK_SUBBLOCKS (current_block
));
3606 current_block
= BLOCK_SUPERCONTEXT (current_block
);
3612 /* Reverse the order of elements in the chain T of blocks,
3613 and return the new head of the chain (old last element). */
3616 blocks_nreverse (tree t
)
3618 tree prev
= 0, decl
, next
;
3619 for (decl
= t
; decl
; decl
= next
)
3621 next
= BLOCK_CHAIN (decl
);
3622 BLOCK_CHAIN (decl
) = prev
;
3628 /* Count the subblocks of the list starting with BLOCK. If VECTOR is
3629 non-NULL, list them all into VECTOR, in a depth-first preorder
3630 traversal of the block tree. Also clear TREE_ASM_WRITTEN in all
3634 all_blocks (tree block
, tree
*vector
)
3640 TREE_ASM_WRITTEN (block
) = 0;
3642 /* Record this block. */
3644 vector
[n_blocks
] = block
;
3648 /* Record the subblocks, and their subblocks... */
3649 n_blocks
+= all_blocks (BLOCK_SUBBLOCKS (block
),
3650 vector
? vector
+ n_blocks
: 0);
3651 block
= BLOCK_CHAIN (block
);
3657 /* Return a vector containing all the blocks rooted at BLOCK. The
3658 number of elements in the vector is stored in N_BLOCKS_P. The
3659 vector is dynamically allocated; it is the caller's responsibility
3660 to call `free' on the pointer returned. */
3663 get_block_vector (tree block
, int *n_blocks_p
)
3667 *n_blocks_p
= all_blocks (block
, NULL
);
3668 block_vector
= XNEWVEC (tree
, *n_blocks_p
);
3669 all_blocks (block
, block_vector
);
3671 return block_vector
;
3674 static GTY(()) int next_block_index
= 2;
3676 /* Set BLOCK_NUMBER for all the blocks in FN. */
3679 number_blocks (tree fn
)
3685 /* For SDB and XCOFF debugging output, we start numbering the blocks
3686 from 1 within each function, rather than keeping a running
3688 #if defined (SDB_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
3689 if (write_symbols
== SDB_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
3690 next_block_index
= 1;
3693 block_vector
= get_block_vector (DECL_INITIAL (fn
), &n_blocks
);
3695 /* The top-level BLOCK isn't numbered at all. */
3696 for (i
= 1; i
< n_blocks
; ++i
)
3697 /* We number the blocks from two. */
3698 BLOCK_NUMBER (block_vector
[i
]) = next_block_index
++;
3700 free (block_vector
);
3705 /* If VAR is present in a subblock of BLOCK, return the subblock. */
3708 debug_find_var_in_block_tree (tree var
, tree block
)
3712 for (t
= BLOCK_VARS (block
); t
; t
= TREE_CHAIN (t
))
3716 for (t
= BLOCK_SUBBLOCKS (block
); t
; t
= TREE_CHAIN (t
))
3718 tree ret
= debug_find_var_in_block_tree (var
, t
);
3726 /* Keep track of whether we're in a dummy function context. If we are,
3727 we don't want to invoke the set_current_function hook, because we'll
3728 get into trouble if the hook calls target_reinit () recursively or
3729 when the initial initialization is not yet complete. */
3731 static bool in_dummy_function
;
3733 /* Invoke the target hook when setting cfun. Update the optimization options
3734 if the function uses different options than the default. */
3737 invoke_set_current_function_hook (tree fndecl
)
3739 if (!in_dummy_function
)
3741 tree opts
= ((fndecl
)
3742 ? DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl
)
3743 : optimization_default_node
);
3746 opts
= optimization_default_node
;
3748 /* Change optimization options if needed. */
3749 if (optimization_current_node
!= opts
)
3751 optimization_current_node
= opts
;
3752 cl_optimization_restore (TREE_OPTIMIZATION (opts
));
3755 targetm
.set_current_function (fndecl
);
3759 /* cfun should never be set directly; use this function. */
3762 set_cfun (struct function
*new_cfun
)
3764 if (cfun
!= new_cfun
)
3767 invoke_set_current_function_hook (new_cfun
? new_cfun
->decl
: NULL_TREE
);
3771 /* Keep track of the cfun stack. */
3773 typedef struct function
*function_p
;
3775 DEF_VEC_P(function_p
);
3776 DEF_VEC_ALLOC_P(function_p
,heap
);
3778 /* Initialized with NOGC, making this poisonous to the garbage collector. */
3780 static VEC(function_p
,heap
) *cfun_stack
;
3782 /* Push the current cfun onto the stack, and set cfun to new_cfun. */
3785 push_cfun (struct function
*new_cfun
)
3787 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3788 set_cfun (new_cfun
);
3791 /* Pop cfun from the stack. */
3796 struct function
*new_cfun
= VEC_pop (function_p
, cfun_stack
);
3797 set_cfun (new_cfun
);
3800 /* Return value of funcdef and increase it. */
3802 get_next_funcdef_no (void)
3804 return funcdef_no
++;
3807 /* Allocate a function structure for FNDECL and set its contents
3808 to the defaults. Set cfun to the newly-allocated object.
3809 Some of the helper functions invoked during initialization assume
3810 that cfun has already been set. Therefore, assign the new object
3811 directly into cfun and invoke the back end hook explicitly at the
3812 very end, rather than initializing a temporary and calling set_cfun
3815 ABSTRACT_P is true if this is a function that will never be seen by
3816 the middle-end. Such functions are front-end concepts (like C++
3817 function templates) that do not correspond directly to functions
3818 placed in object files. */
3821 allocate_struct_function (tree fndecl
, bool abstract_p
)
3824 tree fntype
= fndecl
? TREE_TYPE (fndecl
) : NULL_TREE
;
3826 cfun
= GGC_CNEW (struct function
);
3828 cfun
->function_frequency
= FUNCTION_FREQUENCY_NORMAL
;
3830 init_eh_for_function ();
3832 if (init_machine_status
)
3833 cfun
->machine
= (*init_machine_status
) ();
3835 #ifdef OVERRIDE_ABI_FORMAT
3836 OVERRIDE_ABI_FORMAT (fndecl
);
3839 if (fndecl
!= NULL_TREE
)
3841 DECL_STRUCT_FUNCTION (fndecl
) = cfun
;
3842 cfun
->decl
= fndecl
;
3843 current_function_funcdef_no
= get_next_funcdef_no ();
3845 result
= DECL_RESULT (fndecl
);
3846 if (!abstract_p
&& aggregate_value_p (result
, fndecl
))
3848 #ifdef PCC_STATIC_STRUCT_RETURN
3849 cfun
->returns_pcc_struct
= 1;
3851 cfun
->returns_struct
= 1;
3856 && TYPE_ARG_TYPES (fntype
) != 0
3857 && (TREE_VALUE (tree_last (TYPE_ARG_TYPES (fntype
)))
3858 != void_type_node
));
3860 /* Assume all registers in stdarg functions need to be saved. */
3861 cfun
->va_list_gpr_size
= VA_LIST_MAX_GPR_SIZE
;
3862 cfun
->va_list_fpr_size
= VA_LIST_MAX_FPR_SIZE
;
3865 invoke_set_current_function_hook (fndecl
);
3868 /* This is like allocate_struct_function, but pushes a new cfun for FNDECL
3869 instead of just setting it. */
3872 push_struct_function (tree fndecl
)
3874 VEC_safe_push (function_p
, heap
, cfun_stack
, cfun
);
3875 allocate_struct_function (fndecl
, false);
3878 /* Reset cfun, and other non-struct-function variables to defaults as
3879 appropriate for emitting rtl at the start of a function. */
3882 prepare_function_start (void)
3884 gcc_assert (!crtl
->emit
.x_last_insn
);
3886 init_varasm_status ();
3888 default_rtl_profile ();
3890 cse_not_expected
= ! optimize
;
3892 /* Caller save not needed yet. */
3893 caller_save_needed
= 0;
3895 /* We haven't done register allocation yet. */
3898 /* Indicate that we have not instantiated virtual registers yet. */
3899 virtuals_instantiated
= 0;
3901 /* Indicate that we want CONCATs now. */
3902 generating_concat_p
= 1;
3904 /* Indicate we have no need of a frame pointer yet. */
3905 frame_pointer_needed
= 0;
3908 /* Initialize the rtl expansion mechanism so that we can do simple things
3909 like generate sequences. This is used to provide a context during global
3910 initialization of some passes. You must call expand_dummy_function_end
3911 to exit this context. */
3914 init_dummy_function_start (void)
3916 gcc_assert (!in_dummy_function
);
3917 in_dummy_function
= true;
3918 push_struct_function (NULL_TREE
);
3919 prepare_function_start ();
3922 /* Generate RTL for the start of the function SUBR (a FUNCTION_DECL tree node)
3923 and initialize static variables for generating RTL for the statements
3927 init_function_start (tree subr
)
3929 if (subr
&& DECL_STRUCT_FUNCTION (subr
))
3930 set_cfun (DECL_STRUCT_FUNCTION (subr
));
3932 allocate_struct_function (subr
, false);
3933 prepare_function_start ();
3935 /* Warn if this value is an aggregate type,
3936 regardless of which calling convention we are using for it. */
3937 if (AGGREGATE_TYPE_P (TREE_TYPE (DECL_RESULT (subr
))))
3938 warning (OPT_Waggregate_return
, "function returns an aggregate");
3941 /* Make sure all values used by the optimization passes have sane
3944 init_function_for_compilation (void)
3948 /* No prologue/epilogue insns yet. Make sure that these vectors are
3950 gcc_assert (VEC_length (int, prologue
) == 0);
3951 gcc_assert (VEC_length (int, epilogue
) == 0);
3952 gcc_assert (VEC_length (int, sibcall_epilogue
) == 0);
3956 struct rtl_opt_pass pass_init_function
=
3962 init_function_for_compilation
, /* execute */
3965 0, /* static_pass_number */
3967 0, /* properties_required */
3968 0, /* properties_provided */
3969 0, /* properties_destroyed */
3970 0, /* todo_flags_start */
3971 0 /* todo_flags_finish */
3977 expand_main_function (void)
3979 #if (defined(INVOKE__main) \
3980 || (!defined(HAS_INIT_SECTION) \
3981 && !defined(INIT_SECTION_ASM_OP) \
3982 && !defined(INIT_ARRAY_SECTION_ASM_OP)))
3983 emit_library_call (init_one_libfunc (NAME__MAIN
), LCT_NORMAL
, VOIDmode
, 0);
3987 /* Expand code to initialize the stack_protect_guard. This is invoked at
3988 the beginning of a function to be protected. */
3990 #ifndef HAVE_stack_protect_set
3991 # define HAVE_stack_protect_set 0
3992 # define gen_stack_protect_set(x,y) (gcc_unreachable (), NULL_RTX)
3996 stack_protect_prologue (void)
3998 tree guard_decl
= targetm
.stack_protect_guard ();
4001 /* Avoid expand_expr here, because we don't want guard_decl pulled
4002 into registers unless absolutely necessary. And we know that
4003 crtl->stack_protect_guard is a local stack slot, so this skips
4005 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4006 y
= validize_mem (DECL_RTL (guard_decl
));
4008 /* Allow the target to copy from Y to X without leaking Y into a
4010 if (HAVE_stack_protect_set
)
4012 rtx insn
= gen_stack_protect_set (x
, y
);
4020 /* Otherwise do a straight move. */
4021 emit_move_insn (x
, y
);
4024 /* Expand code to verify the stack_protect_guard. This is invoked at
4025 the end of a function to be protected. */
4027 #ifndef HAVE_stack_protect_test
4028 # define HAVE_stack_protect_test 0
4029 # define gen_stack_protect_test(x, y, z) (gcc_unreachable (), NULL_RTX)
4033 stack_protect_epilogue (void)
4035 tree guard_decl
= targetm
.stack_protect_guard ();
4036 rtx label
= gen_label_rtx ();
4039 /* Avoid expand_expr here, because we don't want guard_decl pulled
4040 into registers unless absolutely necessary. And we know that
4041 crtl->stack_protect_guard is a local stack slot, so this skips
4043 x
= validize_mem (DECL_RTL (crtl
->stack_protect_guard
));
4044 y
= validize_mem (DECL_RTL (guard_decl
));
4046 /* Allow the target to compare Y with X without leaking either into
4048 switch (HAVE_stack_protect_test
!= 0)
4051 tmp
= gen_stack_protect_test (x
, y
, label
);
4060 emit_cmp_and_jump_insns (x
, y
, EQ
, NULL_RTX
, ptr_mode
, 1, label
);
4064 /* The noreturn predictor has been moved to the tree level. The rtl-level
4065 predictors estimate this branch about 20%, which isn't enough to get
4066 things moved out of line. Since this is the only extant case of adding
4067 a noreturn function at the rtl level, it doesn't seem worth doing ought
4068 except adding the prediction by hand. */
4069 tmp
= get_last_insn ();
4071 predict_insn_def (tmp
, PRED_NORETURN
, TAKEN
);
4073 expand_expr_stmt (targetm
.stack_protect_fail ());
4077 /* Start the RTL for a new function, and set variables used for
4079 SUBR is the FUNCTION_DECL node.
4080 PARMS_HAVE_CLEANUPS is nonzero if there are cleanups associated with
4081 the function's parameters, which must be run at any return statement. */
4084 expand_function_start (tree subr
)
4086 /* Make sure volatile mem refs aren't considered
4087 valid operands of arithmetic insns. */
4088 init_recog_no_volatile ();
4092 && ! DECL_NO_INSTRUMENT_FUNCTION_ENTRY_EXIT (subr
));
4095 = (stack_limit_rtx
!= NULL_RTX
&& ! DECL_NO_LIMIT_STACK (subr
));
4097 /* Make the label for return statements to jump to. Do not special
4098 case machines with special return instructions -- they will be
4099 handled later during jump, ifcvt, or epilogue creation. */
4100 return_label
= gen_label_rtx ();
4102 /* Initialize rtx used to return the value. */
4103 /* Do this before assign_parms so that we copy the struct value address
4104 before any library calls that assign parms might generate. */
4106 /* Decide whether to return the value in memory or in a register. */
4107 if (aggregate_value_p (DECL_RESULT (subr
), subr
))
4109 /* Returning something that won't go in a register. */
4110 rtx value_address
= 0;
4112 #ifdef PCC_STATIC_STRUCT_RETURN
4113 if (cfun
->returns_pcc_struct
)
4115 int size
= int_size_in_bytes (TREE_TYPE (DECL_RESULT (subr
)));
4116 value_address
= assemble_static_space (size
);
4121 rtx sv
= targetm
.calls
.struct_value_rtx (TREE_TYPE (subr
), 2);
4122 /* Expect to be passed the address of a place to store the value.
4123 If it is passed as an argument, assign_parms will take care of
4127 value_address
= gen_reg_rtx (Pmode
);
4128 emit_move_insn (value_address
, sv
);
4133 rtx x
= value_address
;
4134 if (!DECL_BY_REFERENCE (DECL_RESULT (subr
)))
4136 x
= gen_rtx_MEM (DECL_MODE (DECL_RESULT (subr
)), x
);
4137 set_mem_attributes (x
, DECL_RESULT (subr
), 1);
4139 SET_DECL_RTL (DECL_RESULT (subr
), x
);
4142 else if (DECL_MODE (DECL_RESULT (subr
)) == VOIDmode
)
4143 /* If return mode is void, this decl rtl should not be used. */
4144 SET_DECL_RTL (DECL_RESULT (subr
), NULL_RTX
);
4147 /* Compute the return values into a pseudo reg, which we will copy
4148 into the true return register after the cleanups are done. */
4149 tree return_type
= TREE_TYPE (DECL_RESULT (subr
));
4150 if (TYPE_MODE (return_type
) != BLKmode
4151 && targetm
.calls
.return_in_msb (return_type
))
4152 /* expand_function_end will insert the appropriate padding in
4153 this case. Use the return value's natural (unpadded) mode
4154 within the function proper. */
4155 SET_DECL_RTL (DECL_RESULT (subr
),
4156 gen_reg_rtx (TYPE_MODE (return_type
)));
4159 /* In order to figure out what mode to use for the pseudo, we
4160 figure out what the mode of the eventual return register will
4161 actually be, and use that. */
4162 rtx hard_reg
= hard_function_value (return_type
, subr
, 0, 1);
4164 /* Structures that are returned in registers are not
4165 aggregate_value_p, so we may see a PARALLEL or a REG. */
4166 if (REG_P (hard_reg
))
4167 SET_DECL_RTL (DECL_RESULT (subr
),
4168 gen_reg_rtx (GET_MODE (hard_reg
)));
4171 gcc_assert (GET_CODE (hard_reg
) == PARALLEL
);
4172 SET_DECL_RTL (DECL_RESULT (subr
), gen_group_rtx (hard_reg
));
4176 /* Set DECL_REGISTER flag so that expand_function_end will copy the
4177 result to the real return register(s). */
4178 DECL_REGISTER (DECL_RESULT (subr
)) = 1;
4181 /* Initialize rtx for parameters and local variables.
4182 In some cases this requires emitting insns. */
4183 assign_parms (subr
);
4185 /* If function gets a static chain arg, store it. */
4186 if (cfun
->static_chain_decl
)
4188 tree parm
= cfun
->static_chain_decl
;
4189 rtx local
= gen_reg_rtx (Pmode
);
4191 set_decl_incoming_rtl (parm
, static_chain_incoming_rtx
, false);
4192 SET_DECL_RTL (parm
, local
);
4193 mark_reg_pointer (local
, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (parm
))));
4195 emit_move_insn (local
, static_chain_incoming_rtx
);
4198 /* If the function receives a non-local goto, then store the
4199 bits we need to restore the frame pointer. */
4200 if (cfun
->nonlocal_goto_save_area
)
4205 /* ??? We need to do this save early. Unfortunately here is
4206 before the frame variable gets declared. Help out... */
4207 tree var
= TREE_OPERAND (cfun
->nonlocal_goto_save_area
, 0);
4208 if (!DECL_RTL_SET_P (var
))
4211 t_save
= build4 (ARRAY_REF
, ptr_type_node
,
4212 cfun
->nonlocal_goto_save_area
,
4213 integer_zero_node
, NULL_TREE
, NULL_TREE
);
4214 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
4215 r_save
= convert_memory_address (Pmode
, r_save
);
4217 emit_move_insn (r_save
, targetm
.builtin_setjmp_frame_value ());
4218 update_nonlocal_goto_save_area ();
4221 /* The following was moved from init_function_start.
4222 The move is supposed to make sdb output more accurate. */
4223 /* Indicate the beginning of the function body,
4224 as opposed to parm setup. */
4225 emit_note (NOTE_INSN_FUNCTION_BEG
);
4227 gcc_assert (NOTE_P (get_last_insn ()));
4229 parm_birth_insn
= get_last_insn ();
4234 PROFILE_HOOK (current_function_funcdef_no
);
4238 /* After the display initializations is where the stack checking
4240 if(flag_stack_check
)
4241 stack_check_probe_note
= emit_note (NOTE_INSN_DELETED
);
4243 /* Make sure there is a line number after the function entry setup code. */
4244 force_next_line_note ();
4247 /* Undo the effects of init_dummy_function_start. */
4249 expand_dummy_function_end (void)
4251 gcc_assert (in_dummy_function
);
4253 /* End any sequences that failed to be closed due to syntax errors. */
4254 while (in_sequence_p ())
4257 /* Outside function body, can't compute type's actual size
4258 until next function's body starts. */
4260 free_after_parsing (cfun
);
4261 free_after_compilation (cfun
);
4263 in_dummy_function
= false;
4266 /* Call DOIT for each hard register used as a return value from
4267 the current function. */
4270 diddle_return_value (void (*doit
) (rtx
, void *), void *arg
)
4272 rtx outgoing
= crtl
->return_rtx
;
4277 if (REG_P (outgoing
))
4278 (*doit
) (outgoing
, arg
);
4279 else if (GET_CODE (outgoing
) == PARALLEL
)
4283 for (i
= 0; i
< XVECLEN (outgoing
, 0); i
++)
4285 rtx x
= XEXP (XVECEXP (outgoing
, 0, i
), 0);
4287 if (REG_P (x
) && REGNO (x
) < FIRST_PSEUDO_REGISTER
)
4294 do_clobber_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4300 clobber_return_register (void)
4302 diddle_return_value (do_clobber_return_reg
, NULL
);
4304 /* In case we do use pseudo to return value, clobber it too. */
4305 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4307 tree decl_result
= DECL_RESULT (current_function_decl
);
4308 rtx decl_rtl
= DECL_RTL (decl_result
);
4309 if (REG_P (decl_rtl
) && REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
)
4311 do_clobber_return_reg (decl_rtl
, NULL
);
4317 do_use_return_reg (rtx reg
, void *arg ATTRIBUTE_UNUSED
)
4323 use_return_register (void)
4325 diddle_return_value (do_use_return_reg
, NULL
);
4328 /* Possibly warn about unused parameters. */
4330 do_warn_unused_parameter (tree fn
)
4334 for (decl
= DECL_ARGUMENTS (fn
);
4335 decl
; decl
= TREE_CHAIN (decl
))
4336 if (!TREE_USED (decl
) && TREE_CODE (decl
) == PARM_DECL
4337 && DECL_NAME (decl
) && !DECL_ARTIFICIAL (decl
)
4338 && !TREE_NO_WARNING (decl
))
4339 warning (OPT_Wunused_parameter
, "unused parameter %q+D", decl
);
4342 static GTY(()) rtx initial_trampoline
;
4344 /* Generate RTL for the end of the current function. */
4347 expand_function_end (void)
4351 /* If arg_pointer_save_area was referenced only from a nested
4352 function, we will not have initialized it yet. Do that now. */
4353 if (arg_pointer_save_area
&& ! crtl
->arg_pointer_save_area_init
)
4354 get_arg_pointer_save_area ();
4356 /* If we are doing stack checking and this function makes calls,
4357 do a stack probe at the start of the function to ensure we have enough
4358 space for another stack frame. */
4359 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
4363 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
4367 probe_stack_range (STACK_CHECK_PROTECT
,
4368 GEN_INT (STACK_CHECK_MAX_FRAME_SIZE
));
4371 emit_insn_before (seq
, stack_check_probe_note
);
4376 /* End any sequences that failed to be closed due to syntax errors. */
4377 while (in_sequence_p ())
4380 clear_pending_stack_adjust ();
4381 do_pending_stack_adjust ();
4383 /* Output a linenumber for the end of the function.
4384 SDB depends on this. */
4385 force_next_line_note ();
4386 set_curr_insn_source_location (input_location
);
4388 /* Before the return label (if any), clobber the return
4389 registers so that they are not propagated live to the rest of
4390 the function. This can only happen with functions that drop
4391 through; if there had been a return statement, there would
4392 have either been a return rtx, or a jump to the return label.
4394 We delay actual code generation after the current_function_value_rtx
4396 clobber_after
= get_last_insn ();
4398 /* Output the label for the actual return from the function. */
4399 emit_label (return_label
);
4401 if (USING_SJLJ_EXCEPTIONS
)
4403 /* Let except.c know where it should emit the call to unregister
4404 the function context for sjlj exceptions. */
4405 if (flag_exceptions
)
4406 sjlj_emit_function_exit_after (get_last_insn ());
4410 /* We want to ensure that instructions that may trap are not
4411 moved into the epilogue by scheduling, because we don't
4412 always emit unwind information for the epilogue. */
4413 if (flag_non_call_exceptions
)
4414 emit_insn (gen_blockage ());
4417 /* If this is an implementation of throw, do what's necessary to
4418 communicate between __builtin_eh_return and the epilogue. */
4419 expand_eh_return ();
4421 /* If scalar return value was computed in a pseudo-reg, or was a named
4422 return value that got dumped to the stack, copy that to the hard
4424 if (DECL_RTL_SET_P (DECL_RESULT (current_function_decl
)))
4426 tree decl_result
= DECL_RESULT (current_function_decl
);
4427 rtx decl_rtl
= DECL_RTL (decl_result
);
4429 if (REG_P (decl_rtl
)
4430 ? REGNO (decl_rtl
) >= FIRST_PSEUDO_REGISTER
4431 : DECL_REGISTER (decl_result
))
4433 rtx real_decl_rtl
= crtl
->return_rtx
;
4435 /* This should be set in assign_parms. */
4436 gcc_assert (REG_FUNCTION_VALUE_P (real_decl_rtl
));
4438 /* If this is a BLKmode structure being returned in registers,
4439 then use the mode computed in expand_return. Note that if
4440 decl_rtl is memory, then its mode may have been changed,
4441 but that crtl->return_rtx has not. */
4442 if (GET_MODE (real_decl_rtl
) == BLKmode
)
4443 PUT_MODE (real_decl_rtl
, GET_MODE (decl_rtl
));
4445 /* If a non-BLKmode return value should be padded at the least
4446 significant end of the register, shift it left by the appropriate
4447 amount. BLKmode results are handled using the group load/store
4449 if (TYPE_MODE (TREE_TYPE (decl_result
)) != BLKmode
4450 && targetm
.calls
.return_in_msb (TREE_TYPE (decl_result
)))
4452 emit_move_insn (gen_rtx_REG (GET_MODE (decl_rtl
),
4453 REGNO (real_decl_rtl
)),
4455 shift_return_value (GET_MODE (decl_rtl
), true, real_decl_rtl
);
4457 /* If a named return value dumped decl_return to memory, then
4458 we may need to re-do the PROMOTE_MODE signed/unsigned
4460 else if (GET_MODE (real_decl_rtl
) != GET_MODE (decl_rtl
))
4462 int unsignedp
= TYPE_UNSIGNED (TREE_TYPE (decl_result
));
4464 if (targetm
.calls
.promote_function_return (TREE_TYPE (current_function_decl
)))
4465 promote_mode (TREE_TYPE (decl_result
), GET_MODE (decl_rtl
),
4468 convert_move (real_decl_rtl
, decl_rtl
, unsignedp
);
4470 else if (GET_CODE (real_decl_rtl
) == PARALLEL
)
4472 /* If expand_function_start has created a PARALLEL for decl_rtl,
4473 move the result to the real return registers. Otherwise, do
4474 a group load from decl_rtl for a named return. */
4475 if (GET_CODE (decl_rtl
) == PARALLEL
)
4476 emit_group_move (real_decl_rtl
, decl_rtl
);
4478 emit_group_load (real_decl_rtl
, decl_rtl
,
4479 TREE_TYPE (decl_result
),
4480 int_size_in_bytes (TREE_TYPE (decl_result
)));
4482 /* In the case of complex integer modes smaller than a word, we'll
4483 need to generate some non-trivial bitfield insertions. Do that
4484 on a pseudo and not the hard register. */
4485 else if (GET_CODE (decl_rtl
) == CONCAT
4486 && GET_MODE_CLASS (GET_MODE (decl_rtl
)) == MODE_COMPLEX_INT
4487 && GET_MODE_BITSIZE (GET_MODE (decl_rtl
)) <= BITS_PER_WORD
)
4489 int old_generating_concat_p
;
4492 old_generating_concat_p
= generating_concat_p
;
4493 generating_concat_p
= 0;
4494 tmp
= gen_reg_rtx (GET_MODE (decl_rtl
));
4495 generating_concat_p
= old_generating_concat_p
;
4497 emit_move_insn (tmp
, decl_rtl
);
4498 emit_move_insn (real_decl_rtl
, tmp
);
4501 emit_move_insn (real_decl_rtl
, decl_rtl
);
4505 /* If returning a structure, arrange to return the address of the value
4506 in a place where debuggers expect to find it.
4508 If returning a structure PCC style,
4509 the caller also depends on this value.
4510 And cfun->returns_pcc_struct is not necessarily set. */
4511 if (cfun
->returns_struct
4512 || cfun
->returns_pcc_struct
)
4514 rtx value_address
= DECL_RTL (DECL_RESULT (current_function_decl
));
4515 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
4518 if (DECL_BY_REFERENCE (DECL_RESULT (current_function_decl
)))
4519 type
= TREE_TYPE (type
);
4521 value_address
= XEXP (value_address
, 0);
4523 outgoing
= targetm
.calls
.function_value (build_pointer_type (type
),
4524 current_function_decl
, true);
4526 /* Mark this as a function return value so integrate will delete the
4527 assignment and USE below when inlining this function. */
4528 REG_FUNCTION_VALUE_P (outgoing
) = 1;
4530 /* The address may be ptr_mode and OUTGOING may be Pmode. */
4531 value_address
= convert_memory_address (GET_MODE (outgoing
),
4534 emit_move_insn (outgoing
, value_address
);
4536 /* Show return register used to hold result (in this case the address
4538 crtl
->return_rtx
= outgoing
;
4541 /* Emit the actual code to clobber return register. */
4546 clobber_return_register ();
4547 expand_naked_return ();
4551 emit_insn_after (seq
, clobber_after
);
4554 /* Output the label for the naked return from the function. */
4555 emit_label (naked_return_label
);
4557 /* @@@ This is a kludge. We want to ensure that instructions that
4558 may trap are not moved into the epilogue by scheduling, because
4559 we don't always emit unwind information for the epilogue. */
4560 if (! USING_SJLJ_EXCEPTIONS
&& flag_non_call_exceptions
)
4561 emit_insn (gen_blockage ());
4563 /* If stack protection is enabled for this function, check the guard. */
4564 if (crtl
->stack_protect_guard
)
4565 stack_protect_epilogue ();
4567 /* If we had calls to alloca, and this machine needs
4568 an accurate stack pointer to exit the function,
4569 insert some code to save and restore the stack pointer. */
4570 if (! EXIT_IGNORE_STACK
4571 && cfun
->calls_alloca
)
4575 emit_stack_save (SAVE_FUNCTION
, &tem
, parm_birth_insn
);
4576 emit_stack_restore (SAVE_FUNCTION
, tem
, NULL_RTX
);
4579 /* ??? This should no longer be necessary since stupid is no longer with
4580 us, but there are some parts of the compiler (eg reload_combine, and
4581 sh mach_dep_reorg) that still try and compute their own lifetime info
4582 instead of using the general framework. */
4583 use_return_register ();
4587 get_arg_pointer_save_area (void)
4589 rtx ret
= arg_pointer_save_area
;
4593 ret
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
4594 arg_pointer_save_area
= ret
;
4597 if (! crtl
->arg_pointer_save_area_init
)
4601 /* Save the arg pointer at the beginning of the function. The
4602 generated stack slot may not be a valid memory address, so we
4603 have to check it and fix it if necessary. */
4605 emit_move_insn (validize_mem (ret
), virtual_incoming_args_rtx
);
4609 push_topmost_sequence ();
4610 emit_insn_after (seq
, entry_of_function ());
4611 pop_topmost_sequence ();
4617 /* Extend a vector that records the INSN_UIDs of INSNS
4618 (a list of one or more insns). */
4621 record_insns (rtx insns
, VEC(int,heap
) **vecp
)
4625 for (tmp
= insns
; tmp
!= NULL_RTX
; tmp
= NEXT_INSN (tmp
))
4626 VEC_safe_push (int, heap
, *vecp
, INSN_UID (tmp
));
4629 /* Set the locator of the insn chain starting at INSN to LOC. */
4631 set_insn_locators (rtx insn
, int loc
)
4633 while (insn
!= NULL_RTX
)
4636 INSN_LOCATOR (insn
) = loc
;
4637 insn
= NEXT_INSN (insn
);
4641 /* Determine how many INSN_UIDs in VEC are part of INSN. Because we can
4642 be running after reorg, SEQUENCE rtl is possible. */
4645 contains (const_rtx insn
, VEC(int,heap
) **vec
)
4649 if (NONJUMP_INSN_P (insn
)
4650 && GET_CODE (PATTERN (insn
)) == SEQUENCE
)
4653 for (i
= XVECLEN (PATTERN (insn
), 0) - 1; i
>= 0; i
--)
4654 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4655 if (INSN_UID (XVECEXP (PATTERN (insn
), 0, i
))
4656 == VEC_index (int, *vec
, j
))
4662 for (j
= VEC_length (int, *vec
) - 1; j
>= 0; --j
)
4663 if (INSN_UID (insn
) == VEC_index (int, *vec
, j
))
4670 prologue_epilogue_contains (const_rtx insn
)
4672 if (contains (insn
, &prologue
))
4674 if (contains (insn
, &epilogue
))
4680 sibcall_epilogue_contains (const_rtx insn
)
4682 if (sibcall_epilogue
)
4683 return contains (insn
, &sibcall_epilogue
);
4688 /* Insert gen_return at the end of block BB. This also means updating
4689 block_for_insn appropriately. */
4692 emit_return_into_block (basic_block bb
)
4694 emit_jump_insn_after (gen_return (), BB_END (bb
));
4696 #endif /* HAVE_return */
4698 /* Generate the prologue and epilogue RTL if the machine supports it. Thread
4699 this into place with notes indicating where the prologue ends and where
4700 the epilogue begins. Update the basic block information when possible. */
4703 thread_prologue_and_epilogue_insns (void)
4707 #if defined (HAVE_sibcall_epilogue) || defined (HAVE_epilogue) || defined (HAVE_return) || defined (HAVE_prologue)
4710 #if defined (HAVE_epilogue) || defined(HAVE_return)
4711 rtx epilogue_end
= NULL_RTX
;
4715 #ifdef HAVE_prologue
4719 seq
= gen_prologue ();
4722 /* Insert an explicit USE for the frame pointer
4723 if the profiling is on and the frame pointer is required. */
4724 if (crtl
->profile
&& frame_pointer_needed
)
4725 emit_use (hard_frame_pointer_rtx
);
4727 /* Retain a map of the prologue insns. */
4728 record_insns (seq
, &prologue
);
4729 emit_note (NOTE_INSN_PROLOGUE_END
);
4731 #ifndef PROFILE_BEFORE_PROLOGUE
4732 /* Ensure that instructions are not moved into the prologue when
4733 profiling is on. The call to the profiling routine can be
4734 emitted within the live range of a call-clobbered register. */
4736 emit_insn (gen_blockage ());
4741 set_insn_locators (seq
, prologue_locator
);
4743 /* Can't deal with multiple successors of the entry block
4744 at the moment. Function should always have at least one
4746 gcc_assert (single_succ_p (ENTRY_BLOCK_PTR
));
4748 insert_insn_on_edge (seq
, single_succ_edge (ENTRY_BLOCK_PTR
));
4753 /* If the exit block has no non-fake predecessors, we don't need
4755 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4756 if ((e
->flags
& EDGE_FAKE
) == 0)
4762 if (optimize
&& HAVE_return
)
4764 /* If we're allowed to generate a simple return instruction,
4765 then by definition we don't need a full epilogue. Examine
4766 the block that falls through to EXIT. If it does not
4767 contain any code, examine its predecessors and try to
4768 emit (conditional) return instructions. */
4773 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4774 if (e
->flags
& EDGE_FALLTHRU
)
4780 /* Verify that there are no active instructions in the last block. */
4781 label
= BB_END (last
);
4782 while (label
&& !LABEL_P (label
))
4784 if (active_insn_p (label
))
4786 label
= PREV_INSN (label
);
4789 if (BB_HEAD (last
) == label
&& LABEL_P (label
))
4793 for (ei2
= ei_start (last
->preds
); (e
= ei_safe_edge (ei2
)); )
4795 basic_block bb
= e
->src
;
4798 if (bb
== ENTRY_BLOCK_PTR
)
4805 if (!JUMP_P (jump
) || JUMP_LABEL (jump
) != label
)
4811 /* If we have an unconditional jump, we can replace that
4812 with a simple return instruction. */
4813 if (simplejump_p (jump
))
4815 emit_return_into_block (bb
);
4819 /* If we have a conditional jump, we can try to replace
4820 that with a conditional return instruction. */
4821 else if (condjump_p (jump
))
4823 if (! redirect_jump (jump
, 0, 0))
4829 /* If this block has only one successor, it both jumps
4830 and falls through to the fallthru block, so we can't
4832 if (single_succ_p (bb
))
4844 /* Fix up the CFG for the successful change we just made. */
4845 redirect_edge_succ (e
, EXIT_BLOCK_PTR
);
4848 /* Emit a return insn for the exit fallthru block. Whether
4849 this is still reachable will be determined later. */
4851 emit_barrier_after (BB_END (last
));
4852 emit_return_into_block (last
);
4853 epilogue_end
= BB_END (last
);
4854 single_succ_edge (last
)->flags
&= ~EDGE_FALLTHRU
;
4859 /* Find the edge that falls through to EXIT. Other edges may exist
4860 due to RETURN instructions, but those don't need epilogues.
4861 There really shouldn't be a mixture -- either all should have
4862 been converted or none, however... */
4864 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4865 if (e
->flags
& EDGE_FALLTHRU
)
4870 #ifdef HAVE_epilogue
4874 epilogue_end
= emit_note (NOTE_INSN_EPILOGUE_BEG
);
4875 seq
= gen_epilogue ();
4876 emit_jump_insn (seq
);
4878 /* Retain a map of the epilogue insns. */
4879 record_insns (seq
, &epilogue
);
4880 set_insn_locators (seq
, epilogue_locator
);
4885 insert_insn_on_edge (seq
, e
);
4893 if (! next_active_insn (BB_END (e
->src
)))
4895 /* We have a fall-through edge to the exit block, the source is not
4896 at the end of the function, and there will be an assembler epilogue
4897 at the end of the function.
4898 We can't use force_nonfallthru here, because that would try to
4899 use return. Inserting a jump 'by hand' is extremely messy, so
4900 we take advantage of cfg_layout_finalize using
4901 fixup_fallthru_exit_predecessor. */
4902 cfg_layout_initialize (0);
4903 FOR_EACH_BB (cur_bb
)
4904 if (cur_bb
->index
>= NUM_FIXED_BLOCKS
4905 && cur_bb
->next_bb
->index
>= NUM_FIXED_BLOCKS
)
4906 cur_bb
->aux
= cur_bb
->next_bb
;
4907 cfg_layout_finalize ();
4913 commit_edge_insertions ();
4915 /* The epilogue insns we inserted may cause the exit edge to no longer
4917 FOR_EACH_EDGE (e
, ei
, EXIT_BLOCK_PTR
->preds
)
4919 if (((e
->flags
& EDGE_FALLTHRU
) != 0)
4920 && returnjump_p (BB_END (e
->src
)))
4921 e
->flags
&= ~EDGE_FALLTHRU
;
4925 #ifdef HAVE_sibcall_epilogue
4926 /* Emit sibling epilogues before any sibling call sites. */
4927 for (ei
= ei_start (EXIT_BLOCK_PTR
->preds
); (e
= ei_safe_edge (ei
)); )
4929 basic_block bb
= e
->src
;
4930 rtx insn
= BB_END (bb
);
4933 || ! SIBLING_CALL_P (insn
))
4940 emit_insn (gen_sibcall_epilogue ());
4944 /* Retain a map of the epilogue insns. Used in life analysis to
4945 avoid getting rid of sibcall epilogue insns. Do this before we
4946 actually emit the sequence. */
4947 record_insns (seq
, &sibcall_epilogue
);
4948 set_insn_locators (seq
, epilogue_locator
);
4950 emit_insn_before (seq
, insn
);
4955 #ifdef HAVE_epilogue
4960 /* Similarly, move any line notes that appear after the epilogue.
4961 There is no need, however, to be quite so anal about the existence
4962 of such a note. Also possibly move
4963 NOTE_INSN_FUNCTION_BEG notes, as those can be relevant for debug
4965 for (insn
= epilogue_end
; insn
; insn
= next
)
4967 next
= NEXT_INSN (insn
);
4969 && (NOTE_KIND (insn
) == NOTE_INSN_FUNCTION_BEG
))
4970 reorder_insns (insn
, insn
, PREV_INSN (epilogue_end
));
4975 /* Threading the prologue and epilogue changes the artificial refs
4976 in the entry and exit blocks. */
4977 epilogue_completed
= 1;
4978 df_update_entry_exit_and_calls ();
4981 /* Reposition the prologue-end and epilogue-begin notes after instruction
4982 scheduling and delayed branch scheduling. */
4985 reposition_prologue_and_epilogue_notes (void)
4987 #if defined (HAVE_prologue) || defined (HAVE_epilogue)
4988 rtx insn
, last
, note
;
4991 if ((len
= VEC_length (int, prologue
)) > 0)
4995 /* Scan from the beginning until we reach the last prologue insn.
4996 We apparently can't depend on basic_block_{head,end} after
4998 for (insn
= get_insns (); insn
; insn
= NEXT_INSN (insn
))
5002 if (NOTE_KIND (insn
) == NOTE_INSN_PROLOGUE_END
)
5005 else if (contains (insn
, &prologue
))
5015 /* Find the prologue-end note if we haven't already, and
5016 move it to just after the last prologue insn. */
5019 for (note
= last
; (note
= NEXT_INSN (note
));)
5021 && NOTE_KIND (note
) == NOTE_INSN_PROLOGUE_END
)
5025 /* Avoid placing note between CODE_LABEL and BASIC_BLOCK note. */
5027 last
= NEXT_INSN (last
);
5028 reorder_insns (note
, note
, last
);
5032 if ((len
= VEC_length (int, epilogue
)) > 0)
5036 /* Scan from the end until we reach the first epilogue insn.
5037 We apparently can't depend on basic_block_{head,end} after
5039 for (insn
= get_last_insn (); insn
; insn
= PREV_INSN (insn
))
5043 if (NOTE_KIND (insn
) == NOTE_INSN_EPILOGUE_BEG
)
5046 else if (contains (insn
, &epilogue
))
5056 /* Find the epilogue-begin note if we haven't already, and
5057 move it to just before the first epilogue insn. */
5060 for (note
= insn
; (note
= PREV_INSN (note
));)
5062 && NOTE_KIND (note
) == NOTE_INSN_EPILOGUE_BEG
)
5066 if (PREV_INSN (last
) != note
)
5067 reorder_insns (note
, note
, PREV_INSN (last
));
5070 #endif /* HAVE_prologue or HAVE_epilogue */
5073 /* Returns the name of the current function. */
5075 current_function_name (void)
5077 return lang_hooks
.decl_printable_name (cfun
->decl
, 2);
5080 /* Returns the raw (mangled) name of the current function. */
5082 current_function_assembler_name (void)
5084 return IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (cfun
->decl
));
5089 rest_of_handle_check_leaf_regs (void)
5091 #ifdef LEAF_REGISTERS
5092 current_function_uses_only_leaf_regs
5093 = optimize
> 0 && only_leaf_regs_used () && leaf_function_p ();
5098 /* Insert a TYPE into the used types hash table of CFUN. */
5100 used_types_insert_helper (tree type
, struct function
*func
)
5102 if (type
!= NULL
&& func
!= NULL
)
5106 if (func
->used_types_hash
== NULL
)
5107 func
->used_types_hash
= htab_create_ggc (37, htab_hash_pointer
,
5108 htab_eq_pointer
, NULL
);
5109 slot
= htab_find_slot (func
->used_types_hash
, type
, INSERT
);
5115 /* Given a type, insert it into the used hash table in cfun. */
5117 used_types_insert (tree t
)
5119 while (POINTER_TYPE_P (t
) || TREE_CODE (t
) == ARRAY_TYPE
)
5121 t
= TYPE_MAIN_VARIANT (t
);
5122 if (debug_info_level
> DINFO_LEVEL_NONE
)
5123 used_types_insert_helper (t
, cfun
);
5126 struct rtl_opt_pass pass_leaf_regs
=
5132 rest_of_handle_check_leaf_regs
, /* execute */
5135 0, /* static_pass_number */
5137 0, /* properties_required */
5138 0, /* properties_provided */
5139 0, /* properties_destroyed */
5140 0, /* todo_flags_start */
5141 0 /* todo_flags_finish */
5146 rest_of_handle_thread_prologue_and_epilogue (void)
5149 cleanup_cfg (CLEANUP_EXPENSIVE
);
5150 /* On some machines, the prologue and epilogue code, or parts thereof,
5151 can be represented as RTL. Doing so lets us schedule insns between
5152 it and the rest of the code and also allows delayed branch
5153 scheduling to operate in the epilogue. */
5155 thread_prologue_and_epilogue_insns ();
5159 struct rtl_opt_pass pass_thread_prologue_and_epilogue
=
5163 "pro_and_epilogue", /* name */
5165 rest_of_handle_thread_prologue_and_epilogue
, /* execute */
5168 0, /* static_pass_number */
5169 TV_THREAD_PROLOGUE_AND_EPILOGUE
, /* tv_id */
5170 0, /* properties_required */
5171 0, /* properties_provided */
5172 0, /* properties_destroyed */
5173 TODO_verify_flow
, /* todo_flags_start */
5176 TODO_df_finish
| TODO_verify_rtl_sharing
|
5177 TODO_ggc_collect
/* todo_flags_finish */
5182 /* This mini-pass fixes fall-out from SSA in asm statements that have
5183 in-out constraints. Say you start with
5186 asm ("": "+mr" (inout));
5189 which is transformed very early to use explicit output and match operands:
5192 asm ("": "=mr" (inout) : "0" (inout));
5195 Or, after SSA and copyprop,
5197 asm ("": "=mr" (inout_2) : "0" (inout_1));
5200 Clearly inout_2 and inout_1 can't be coalesced easily anymore, as
5201 they represent two separate values, so they will get different pseudo
5202 registers during expansion. Then, since the two operands need to match
5203 per the constraints, but use different pseudo registers, reload can
5204 only register a reload for these operands. But reloads can only be
5205 satisfied by hardregs, not by memory, so we need a register for this
5206 reload, just because we are presented with non-matching operands.
5207 So, even though we allow memory for this operand, no memory can be
5208 used for it, just because the two operands don't match. This can
5209 cause reload failures on register-starved targets.
5211 So it's a symptom of reload not being able to use memory for reloads
5212 or, alternatively it's also a symptom of both operands not coming into
5213 reload as matching (in which case the pseudo could go to memory just
5214 fine, as the alternative allows it, and no reload would be necessary).
5215 We fix the latter problem here, by transforming
5217 asm ("": "=mr" (inout_2) : "0" (inout_1));
5222 asm ("": "=mr" (inout_2) : "0" (inout_2)); */
5225 match_asm_constraints_1 (rtx insn
, rtx
*p_sets
, int noutputs
)
5228 bool changed
= false;
5229 rtx op
= SET_SRC (p_sets
[0]);
5230 int ninputs
= ASM_OPERANDS_INPUT_LENGTH (op
);
5231 rtvec inputs
= ASM_OPERANDS_INPUT_VEC (op
);
5232 bool *output_matched
= XALLOCAVEC (bool, noutputs
);
5234 memset (output_matched
, 0, noutputs
* sizeof (bool));
5235 for (i
= 0; i
< ninputs
; i
++)
5237 rtx input
, output
, insns
;
5238 const char *constraint
= ASM_OPERANDS_INPUT_CONSTRAINT (op
, i
);
5242 match
= strtoul (constraint
, &end
, 10);
5243 if (end
== constraint
)
5246 gcc_assert (match
< noutputs
);
5247 output
= SET_DEST (p_sets
[match
]);
5248 input
= RTVEC_ELT (inputs
, i
);
5249 /* Only do the transformation for pseudos. */
5250 if (! REG_P (output
)
5251 || rtx_equal_p (output
, input
)
5252 || (GET_MODE (input
) != VOIDmode
5253 && GET_MODE (input
) != GET_MODE (output
)))
5256 /* We can't do anything if the output is also used as input,
5257 as we're going to overwrite it. */
5258 for (j
= 0; j
< ninputs
; j
++)
5259 if (reg_overlap_mentioned_p (output
, RTVEC_ELT (inputs
, j
)))
5264 /* Avoid changing the same input several times. For
5265 asm ("" : "=mr" (out1), "=mr" (out2) : "0" (in), "1" (in));
5266 only change in once (to out1), rather than changing it
5267 first to out1 and afterwards to out2. */
5270 for (j
= 0; j
< noutputs
; j
++)
5271 if (output_matched
[j
] && input
== SET_DEST (p_sets
[j
]))
5276 output_matched
[match
] = true;
5279 emit_move_insn (output
, input
);
5280 insns
= get_insns ();
5282 emit_insn_before (insns
, insn
);
5284 /* Now replace all mentions of the input with output. We can't
5285 just replace the occurrence in inputs[i], as the register might
5286 also be used in some other input (or even in an address of an
5287 output), which would mean possibly increasing the number of
5288 inputs by one (namely 'output' in addition), which might pose
5289 a too complicated problem for reload to solve. E.g. this situation:
5291 asm ("" : "=r" (output), "=m" (input) : "0" (input))
5293 Here 'input' is used in two occurrences as input (once for the
5294 input operand, once for the address in the second output operand).
5295 If we would replace only the occurrence of the input operand (to
5296 make the matching) we would be left with this:
5299 asm ("" : "=r" (output), "=m" (input) : "0" (output))
5301 Now we suddenly have two different input values (containing the same
5302 value, but different pseudos) where we formerly had only one.
5303 With more complicated asms this might lead to reload failures
5304 which wouldn't have happen without this pass. So, iterate over
5305 all operands and replace all occurrences of the register used. */
5306 for (j
= 0; j
< noutputs
; j
++)
5307 if (!rtx_equal_p (SET_DEST (p_sets
[j
]), input
)
5308 && reg_overlap_mentioned_p (input
, SET_DEST (p_sets
[j
])))
5309 SET_DEST (p_sets
[j
]) = replace_rtx (SET_DEST (p_sets
[j
]),
5311 for (j
= 0; j
< ninputs
; j
++)
5312 if (reg_overlap_mentioned_p (input
, RTVEC_ELT (inputs
, j
)))
5313 RTVEC_ELT (inputs
, j
) = replace_rtx (RTVEC_ELT (inputs
, j
),
5320 df_insn_rescan (insn
);
5324 rest_of_match_asm_constraints (void)
5327 rtx insn
, pat
, *p_sets
;
5330 if (!crtl
->has_asm_statement
)
5333 df_set_flags (DF_DEFER_INSN_RESCAN
);
5336 FOR_BB_INSNS (bb
, insn
)
5341 pat
= PATTERN (insn
);
5342 if (GET_CODE (pat
) == PARALLEL
)
5343 p_sets
= &XVECEXP (pat
, 0, 0), noutputs
= XVECLEN (pat
, 0);
5344 else if (GET_CODE (pat
) == SET
)
5345 p_sets
= &PATTERN (insn
), noutputs
= 1;
5349 if (GET_CODE (*p_sets
) == SET
5350 && GET_CODE (SET_SRC (*p_sets
)) == ASM_OPERANDS
)
5351 match_asm_constraints_1 (insn
, p_sets
, noutputs
);
5355 return TODO_df_finish
;
5358 struct rtl_opt_pass pass_match_asm_constraints
=
5362 "asmcons", /* name */
5364 rest_of_match_asm_constraints
, /* execute */
5367 0, /* static_pass_number */
5369 0, /* properties_required */
5370 0, /* properties_provided */
5371 0, /* properties_destroyed */
5372 0, /* todo_flags_start */
5373 TODO_dump_func
/* todo_flags_finish */
5378 #include "gt-function.h"